Ventilation system for patient interface

Abstract

A vent structure may include a vent housing including an inlet, an outlet, at least one vent orifice, and a membrane having spaced apart first and second ends, the membrane having a movable portion between the first and second ends. The movable portion may be radially spaced from the membrane facing surface inside the vent housing to form an exhaust gas flow passage therebetween allowing exhaust gas to flow from the pressurized volume through the exhaust gas flow passage via the exhaust gas orifice into the atmosphere. The movable portion may be elastically deformable and configured to move radially relative to the membrane-facing surface in response to a pressure difference between an inner side of the membrane and an outer side of the membrane to vary a cross-sectional area of the exhaust flow channel and regulate the vent flow.

Description

[0001] 1 Cross-reference to related applications

[0002] This application is a divisional application of the patent application with application number 202080020546.7, application date February 26, 2020, and invention name “Ventilation system for patient interface”, and the patent application with application number 202080020546.7 is the Chinese national phase application of the international application PCT / AU2020 / 050167 filed on February 26, 2020, which claims priority to U.S. Provisional Application No. 62 / 810,640 filed on February 26, 2019, which is incorporated herein by reference in its entirety. 2 Background Technology 2.1 Technical Field

[0003] The present technology relates to one or more of the screening, diagnosis, monitoring, treatment, prevention and improvement of respiratory-related disorders. The present technology also relates to medical devices or equipment and their uses.

[0004] 2.2 Description of Related Technologies

[0005] 2.2.1 Human respiratory system and its diseases

[0006] The human respiratory system facilitates gas exchange. The nose and mouth form the entrance to the patient's airway.

[0007] The airways include a series of branching tubes, which become narrower, shorter and more numerous as they penetrate deeper into the lungs. The main function of the lungs is gas exchange, allowing oxygen to move from the inhaled air into the venous blood and allowing carbon dioxide to move in the opposite direction. The trachea is divided into the left and right main bronchi, which are ultimately divided into terminal bronchioles. The bronchi constitute the conducting airways, but do not participate in gas exchange. Further branches of the airways lead to the respiratory bronchioles and ultimately to the alveoli. The alveolar region of the lungs is the area where gas exchange occurs and is called the respiratory zone. Referring to " Respiratory Physiology (Respiratory Physiology)" published by John B.West, Lippincott Williams & Wilkins in 2012, the 9th edition.

[0008] There is a range of respiratory disorders. Some disorders can be characterised by specific events such as apnea, hypopnea and hyperpnea.

[0009] Examples of breathing disorders include obstructive sleep apnea (OSA), Cheyne-Stokes respiration (CSR), respiratory insufficiency, obesity hyperventilation syndrome (OHS), chronic obstructive pulmonary disease (COPD), neuromuscular disease (NMD), and chest wall disorders.

[0010] Obstructive sleep apnea (OSA) is a form of sleep-disordered breathing (SDB) characterized by events including occlusion or obstruction of the upper airway during sleep. It is caused by a combination of an abnormally small upper airway and normal loss of muscle tone in the tongue, soft palate, and posterior oropharyngeal wall area during sleep. The condition causes affected patients to stop breathing, typically for periods of 30 to 120 seconds, sometimes 200 to 300 times per night. This often leads to excessive daytime sleepiness and can cause cardiovascular disease and brain damage. The syndrome is a common disease, especially in middle-aged overweight men, but the people affected may not be aware of this problem. Referring to U.S. Patent No. 4,944,310 (Sullivan).

[0011] Cheyne-Stokes respiration (CSR) is another form of sleep-disordered breathing. CSR is an obstruction of the patient's respiratory controller, in which there is a rhythmic alternating cycle of boom-and-bust ventilation called a CSR cycle. CSR is characterized by repeated deoxygenation and reoxygenation of arterial blood. CSR may be harmful due to repetitive hypoxia. In some patients, CSR is associated with repeated awakenings from sleep, which leads to severe sleep disruption, increased sympathetic nerve activity, and increased afterload. See U.S. Patent No. 6,532,959 (Berthon-Jones).

[0012] Respiratory failure is an umbrella term for respiratory diseases in which the lungs cannot take in enough oxygen or exhale enough CO2 to meet the patient's needs. Respiratory failure can include some or all of the following conditions.

[0013] Patients with respiratory insufficiency, a form of respiratory failure, may experience abnormal shortness of breath during exercise.

[0014] Obesity hyperventilation syndrome (OHS) is defined as the combination of severe obesity and chronic hypercapnia during wakefulness, in the absence of other known causes of hypoventilation. Symptoms include dyspnea, morning headaches, and excessive daytime sleepiness.

[0015] Chronic obstructive pulmonary disease (COPD) encompasses any of a group of lower airway diseases that share certain common features. These include increased resistance to air movement, a prolonged expiratory phase of breathing, and a loss of the lungs' normal elasticity. Examples of COPD are emphysema and chronic bronchitis. COPD is caused by chronic smoking (a major risk factor), occupational exposure, air pollution, and genetic factors. Symptoms include: dyspnea on exertion, a chronic cough, and sputum production.

[0016] Neuromuscular disease (NMD) is a broad term that encompasses many diseases and ailments that impair muscle function directly through intrinsic muscle pathology or indirectly through neuropathology. Some NMD patients are characterized by progressive muscle damage, which leads to loss of the ability to walk, wheelchair use, dysphagia, respiratory muscle weakness, and ultimately death from respiratory failure. Neuromuscular diseases can be divided into rapidly progressive and slowly progressive: (i) rapidly progressive disease: characterized by muscle damage that worsens over several months and leads to death within a few years (e.g., amyotrophic lateral sclerosis (ALS) and Duchenne muscular dystrophy (DMD) in adolescents; (ii) variable or slowly progressive disease: characterized by muscle damage that worsens over several years and only slightly shortens life expectancy (e.g., limb-girdle, facioscapulohumeral, and myotonic dystrophy). Symptoms of respiratory failure in NMD include: increasing general weakness, dysphagia, dyspnea during exercise and at rest, fatigue, drowsiness, morning headaches, and difficulty concentrating and mood changes.

[0017] Chest wall diseases are a group of thoracic deformities that result in inefficient connections between the respiratory muscles and the thorax. These diseases are often characterized by restrictive defects and have the potential for long-term hypercapnic respiratory failure. Scoliosis and / or kyphoscoliosis can cause severe respiratory failure. Symptoms of respiratory failure include dyspnea during exertion, peripheral edema, orthopnea, recurrent chest infections, morning headaches, fatigue, poor sleep quality, and loss of appetite.

[0018] A range of treatments have been used to treat or ameliorate these conditions. Furthermore, such treatments can be used to prevent breathing problems in otherwise healthy individuals. However, these have a number of drawbacks.

[0019] 2.2.2 Treatment

[0020] Various therapies, such as continuous positive airway pressure (CPAP) therapy, non-invasive ventilation (NIV), and invasive ventilation (IV), have been used to treat one or more of the above-mentioned breathing disorders.

[0021] Continuous positive airway pressure (CPAP) therapy has been used to treat obstructive sleep apnea (OSA). The mechanism of action is that the continuous positive airway pressure acts as a pneumatic splint and can prevent upper airway occlusion, such as by pushing the soft palate and tongue forward and away from the posterior oropharyngeal wall. Treatment of OSA treated with CPAP can be voluntary, so if a patient finds the device used to provide such treatment to be any one or more of: uncomfortable, difficult to use, expensive, and unsightly, the patient may choose not to comply with the treatment.

[0022] Non-invasive ventilation (NIV) provides ventilation support to the patient through the upper airway to assist the patient's breathing and / or maintain adequate oxygen levels in the body by performing some or all of the work of breathing. Ventilatory support is provided via a non-invasive patient interface. NIV has been used to treat CSR and respiratory failure, such as OHS, COPD, NMD, and chest wall disease. In some forms, the comfort and effectiveness of these treatments can be improved.

[0023] Non-invasive ventilation (IV) provides ventilation support to patients who are unable to breathe effectively on their own and can be provided using a tracheostomy tube. In some forms, the comfort and effectiveness of these treatments can be improved.

[0024] 2.2.3 Treatment system

[0025] These therapies can be provided by a therapeutic system or device.Such systems and devices can also be used to screen, diagnose, or monitor a condition without treating it.

[0026] The therapy system may include a respiratory pressure therapy device (RPT device), air circuit, humidifier, patient interface, and data management.

[0027] Another form of treatment system is a mandibular repositioning device.

[0028] 2.2.3.1 Patient interface

[0029] The patient interface can be used to couple the respiratory apparatus to its wearer, for example by providing an air flow to the entrance of the airway. The air flow can be provided to the patient's nose and / or mouth via a mask, to the mouth via a tube, or to the patient's trachea via a tracheostomy tube. Depending on the treatment to be applied, the patient interface can form a seal with, for example, an area of ​​the patient's face to facilitate the delivery of gas at a pressure that is sufficiently different from the ambient pressure (e.g., a positive pressure of approximately 10 cmH2O relative to the ambient pressure) to achieve the treatment. For other forms of treatment, such as oxygen delivery, the patient interface may not include a seal sufficient to facilitate the delivery of a gas supply at a positive pressure of approximately 10 cmH2O to the airway.

[0030] Certain other mask systems may not be functionally suitable for this application. For example, a purely cosmetic mask may not maintain adequate pressure. A mask system used for underwater swimming or diving may be configured to prevent the ingress of water from a higher external pressure, but will not maintain the internal air at a pressure higher than ambient pressure.

[0031] Certain masks may be clinically unsuitable for this technology, for example if they block airflow through the nose and only allow it through the mouth.

[0032] Certain masks may be uncomfortable or impractical with the present technology if the patient is required to insert a portion of the mask structure into their mouth to create and maintain a seal with their lips.

[0033] Certain masks may be impractical to use while sleeping, such as when lying on your side in bed with your head on a pillow.

[0034] Designing a patient interface presents many challenges. The face has a complex three-dimensional shape. The size and shape of the nose and head vary significantly between individuals. Because the head is composed of bone, cartilage, and soft tissue, different areas of the face respond differently to mechanical forces. The jaw or mandible can move relative to other bones of the skull. And the entire head can move during respiratory therapy.

[0035] As a result of these challenges, some masks suffer from one or more problems of being protruding, aesthetically undesirable, expensive, poorly fitting, difficult to use, and uncomfortable, particularly when worn for extended periods of time or when the patient is unfamiliar with the system. A mask of the wrong size may lead to reduced compliance, reduced comfort, and poor patient outcomes. Masks designed only for pilots, masks designed as part of personal protective equipment (e.g., filtering masks), SCUBA masks, or masks used for administering anesthetics may be tolerable for their original applications, but nonetheless, such masks may be undesirably uncomfortable when worn for extended periods of time (e.g., several hours). This discomfort may lead to reduced patient compliance with treatment. This is even more true if the mask is worn during sleep.

[0036] CPAP therapy is highly effective in treating certain respiratory conditions, provided the patient adheres to the treatment. If the mask is uncomfortable or difficult to use, the patient may not adhere to the treatment. Because patients are generally advised to clean their masks regularly, if the mask is difficult to clean (e.g., difficult to assemble or disassemble), the patient may not be able to clean their mask, and this may affect patient compliance.

[0037] While a mask used for other applications (such as navigators) may not be suitable for treating sleep-disordered breathing, a mask designed to treat sleep-disordered breathing may be suitable for other applications.

[0038] For these reasons, patient interfaces for delivering CPAP during sleep have emerged as a distinct field.

[0039] 2.2.3.1.1 Sealing structure

[0040] The patient interface may include a seal-forming structure. Because the seal-forming structure is in direct contact with the patient's face, the shape and configuration of the seal-forming structure may directly affect the effectiveness and comfort of the patient interface.

[0041] The patient interface may be characterized in part by the design intent of the seal-forming structure to engage with the face during use. In one form of the patient interface, the seal-forming structure may include a first sub-portion that forms a seal around the left nostril and a second sub-portion that forms a seal around the right nostril. In one form of the patient interface, the seal-forming structure may include a single element that surrounds both nostrils during use. Such a single element may be designed to cover, for example, the supra-labial region and the nasal bridge region of the face. In one form of the patient interface, the seal-forming structure may include an element that surrounds the mouth region during use, for example by forming a seal on the lower lip region of the face. In one form of the patient interface, the seal-forming structure may include a single element that surrounds the nostrils and mouth regions during use. These different types of patient interfaces may be known by their manufacturers by various names, including nasal masks, full-face masks, nasal pillows, nasal sprays, and oronasal masks.

[0042] A seal-forming structure that is effective in one area of ​​a patient's face may be inadequate in another area, e.g., due to different shapes, structures, variability, and sensitive areas of the patient's face. For example, a seal on swimming goggles that covers a patient's forehead may not be suitable for use on the patient's nose.

[0043] Certain seal-forming structures can be designed for mass manufacturing so that one design fits and is comfortable and effective for a wide range of different face shapes and sizes. To the extent there is a mismatch between the shape of the patient's face and the seal-forming structure of a mass-manufactured patient interface, one or both must be modified to form a seal.

[0044] One type of seal-forming structure extends around the periphery of the patient interface and is intended to seal against the patient's face when a force is applied to the patient interface with the seal-forming structure in facing engagement with the patient's face. The seal-forming structure may include an air or fluid-filled cushion, or a molded or formed surface of a resilient sealing element made of an elastomer (e.g., rubber). With this type of seal-forming structure, if the fit is inadequate, a gap will exist between the seal-forming structure and the face, and additional force will be required to force the patient interface against the face to achieve a seal.

[0045] Another type of seal-forming structure incorporates a sheet of thin material located around the perimeter of the mask to provide a self-sealing effect against the patient's face when positive pressure is applied within the mask. Similar to the previous types of seal-forming portions, if the fit between the face and the mask is poor, excessive force may be required to achieve a seal, or the mask may leak. Furthermore, if the shape of the seal-forming structure does not match the shape of the patient, it may wrinkle or buckle during use, causing leaks.

[0046] Another type of seal-forming structure may include friction-fit elements, for example for insertion into a nostril, however some patients find these uncomfortable.

[0047] Another form of seal-forming structure can use adhesive to achieve the seal.Some patients may find it inconvenient to frequently apply and remove adhesive from their face.

[0048] A range of patient interface seal-forming structure technologies are disclosed in the following patent applications assigned to ResMed Limited: WO 1998 / 004,310; WO 2006 / 074,513; WO 2010 / 135,785.

[0049] One form of nasal pillow is found in the Adam circuit manufactured by Puritan-Bennett. Another type of nasal pillow or nasal spray is the subject of US Patent 4,782,832 (Trimble et al.), assigned to Puritan-Bennett Corporation.

[0050] ResMed Limited manufactures the following products that incorporate nasal pillows: SWIFT TM Nasal pillow mask, SWIFT TM II nasal pillow mask, SWIFT TM LT nasal pillow mask, SWIFT TM FX Nasal Pillows and MIRAGE LIBERTY TM Full face mask. The following patent applications assigned to ResMed Limited describe examples of nasal pillow masks: International patent application WO 2004 / 073,778 (describing the ResMed Limited SWIFT TM Other aspects of nasal pillows), U.S. Patent Application 2009 / 0044808 (describing ResMed Limited SWIFT TM LT nasal pillows); International Patent Applications WO 2005 / 063,328 and WO 2006 / 130,903 (describing ResMed Limited MIRAGE LIBERTY TM Other aspects of full face masks); International patent application WO 2009 / 052,560 (describing ResMed Limited SWIFT TM Other aspects of the FX nasal pillows).

[0051] 2.2.3.1.2 Positioning and stabilization

[0052] The seal-forming structure of the patient interface for positive air pressure therapy is subjected to the corresponding force of air pressure to destroy the seal. Therefore, various technologies have been used to position the seal-forming structure and keep it in a sealing relationship with the appropriate part of the face.

[0053] One technique is to use adhesives. See, for example, U.S. Patent Application Publication No. US2010 / 0000534. However, the use of adhesives may be uncomfortable for some people.

[0054] Another technique is to use one or more straps and / or stabilizing harnesses.Many of these harnesses suffer from one or more of the problems of being ill-fitting, bulky, uncomfortable, and inconvenient to use.

[0055] 2.2.3.2 Respiratory Pressure Therapy (RPT) Device

[0056] A respiratory pressure therapy (RPT) device can be used alone or as part of a system to implement one or more of the various therapies described above, for example by operating the device to generate an air flow for delivery to an airway interface. The air flow can be pressurized. Examples of RPT devices include CPAP devices and ventilators.

[0057] Air pressure generators are known in a variety of applications, such as industrial-scale ventilation systems. However, air pressure generators used in medical applications have specific requirements that are not met by more general air pressure generators, such as reliability, size, and weight requirements for medical devices. Furthermore, even devices designed for medical treatment may have drawbacks related to one or more of the following: comfort, noise, ease of use, efficacy, size, weight, manufacturability, cost, and reliability.

[0058] One example of a special requirement for certain RPT devices is noise.

[0059] Table of noise output levels of existing RPT devices (one sample only, measured using the test method specified in ISO 3744 in CPAP mode at 10 cmH2O).

[0060] RPT device name A-weighted sound pressure level dB(A) Years (approximately) <![CDATA[C-Series Tango TM ]]> 31.9 2007 <![CDATA[C-Series Tango with Humidifier TM > 33.1 2007 <![CDATA[S8 Escape TM II]]> 30.5 2005 <![CDATA[With H4i TM S8 Escape humidifier TM II]]> 31.1 2005 <![CDATA[S9 AutoSet TM ]]> 26.5 2010 <![CDATA[S9 AutoSet with H5i Humidifier TM > 28.6 2010

[0061] One known RPT device for treating sleep-disordered breathing is the S9 Sleep Therapy System manufactured by ResMed Limited. Another example of an RPT device is a ventilator. Ventilators such as the ResMed Stellar ventilator for adults and pediatrics are also available. TM The company's portfolio of ventilators can provide invasive and non-invasive non-dependent ventilatory support to a range of patients for the treatment of a variety of conditions, such as, but not limited to, NMD, OHS, and COPD.

[0062] Treated ResMed Elisée TM 150 ventilators and treated ResMed VS III TM Respirators can provide invasive and non-invasive dependent ventilatory support suitable for adult or pediatric patients to treat a variety of conditions. These ventilators provide volume and pressure ventilation modes with single-limb or double-limb circuits. RPT devices typically include a pressure generator, such as a motor-driven blower or a compressed gas reservoir, and are configured to supply an air flow to the patient's airway. In some cases, the air flow can be provided to the patient's airway at a positive pressure. The outlet of the RPT device is connected to a patient interface such as those described above via an air circuit.

[0063] Device designers can be presented with an infinite number of choices to make. Design criteria often conflict, meaning that some design choices are far from conventional or unavoidable. Furthermore, certain aspects of comfort and efficacy may be highly sensitive to small, subtle changes in one or more parameters.

[0064] 2.2.3.3 Humidifier

[0065] Delivering an air flow without humidification can lead to airway drying. Use of a humidifier with an RPT device and patient interface produces humidified gas that minimizes drying of the nasal mucosa and increases patient airway comfort. Additionally, in colder climates, warm air, typically applied to the facial area in and around the patient interface, is more comfortable than cold air.

[0066] Many artificial humidification devices and systems are known, however they do not meet the special requirements of medical humidifiers.

[0067] Medical humidifiers are used to increase the humidity and / or temperature of an air stream relative to the ambient air when needed, typically where the patient is asleep or resting (e.g., in a hospital). Medical humidifiers for bedside placement can be small. A medical humidifier can be configured to humidify and / or heat only the air stream delivered to the patient, without humidifying and / or heating the patient's surroundings. For example, room-based systems (e.g., saunas, air conditioners, or evaporative coolers) can also humidify the air inhaled by the patient, however these systems also humidify and / or heat the entire room, which can cause discomfort to the occupants. In addition, medical humidifiers can have more stringent safety constraints than industrial humidifiers.

[0068] Although many medical humidifiers are known, they may have one or more disadvantages. Some medical humidifiers may provide inadequate humidification and may be difficult or inconvenient for some patients to use.

[0069] 2.2.3.4 Data Management

[0070] There may be a clinical reason for obtaining data to determine whether a patient prescribed a respiratory therapy has been "compliant," e.g., that the patient has used their RPT device in accordance with one or more "compliance rules." One example of a compliance rule for CPAP therapy is a requirement that, in order to be considered compliant, a patient use the RPT device for at least 4 hours a night on at least 21 of 30 consecutive days. To determine patient compliance, a provider of the RPT device (e.g., a healthcare provider) may manually obtain data describing treatment for a patient using the RPT device, calculate usage over a predetermined time period, and compare it to the compliance rules. Once the healthcare provider has determined that the patient has used their RPT device in accordance with the compliance rules, the healthcare provider may notify a third party that the patient is compliant.

[0071] There may be other aspects of patient treatment that would benefit from the communication of treatment data to a third party or external system.

[0072] Existing processes for communicating and managing such data can be one or more of expensive, time consuming, and error prone.

[0073] 2.2.3.5 Mandibular reduction

[0074] A mandibular repositioning device (MRD) or mandibular advancement device (MAD) is one of the treatment options for sleep apnea and snoring. It is an adjustable oral appliance available from a dentist or other supplier that holds the mandible (lower jaw) in a forward position during sleep. An MRD is a removable device that the patient inserts into their mouth before going to sleep and removes after going to sleep. Therefore, an MRD is not designed to be worn all the time. An MRD can be custom made or produced in a standard form and includes a bite impression portion that is designed to allow for a fit to the patient's teeth. This mechanical protrusion of the mandible expands the space behind the tongue, applies tension on the pharyngeal walls to reduce collapse of the airway and reduces palatal vibrations.

[0075] In some examples, the mandibular advancement device may include an upper splint and a lower splint. The upper splint is configured to engage or fit with teeth of the maxilla or the maxilla, and the lower splint is configured to engage or fit with teeth of the maxilla or the mandible. The upper and lower splints are laterally connected by a pair of connecting rods. The pair of connecting rods are symmetrically fixed to the upper and lower splints.

[0076] In this design, the length of the connecting rod is selected so that the mandible remains in an advanced position when the MRD is placed in the patient's mouth. The length of the connecting rod can be adjusted to change the protrusion level of the mandible. The dentist can determine the protrusion level of the mandible, which will determine the length of the connecting rod.

[0077] Some MRDs are constructed to push the mandible forward relative to the maxilla, whereas other MADs (e.g., ResMed Narval CCTM The MRD) is designed to hold the mandible in a forward position. The device also reduces or minimizes side effects on the teeth and the temporomandibular joint (TMJ). Therefore, it is constructed to minimize or prevent any movement of one or more teeth.

[0078] 2.2.3.6 Ventilation techniques

[0079] Some forms of therapy systems may include a vent to allow flushing of exhaled carbon dioxide. The vent may allow gas to flow from an interior space of the patient interface, such as a plenum, to the exterior of the patient interface, such as the surrounding environment.

[0080] The vent may include an orifice through which gas may flow when the mask is in use. Many such vents are noisy. Others may become clogged during use and thus provide inadequate flushing. Some vents may disrupt the sleep of a patient's bed partner, for example, through noise or concentrated airflow.

[0081] ResMed Limited has developed a number of improved mask ventilation technologies, see International Patent Application Publication No. WO 1998 / 034,665; International Patent Application Publication No. WO 2000 / 078,381; U.S. Patent Application No. 6,581,594; U.S. Patent Application Publication No. US 2009 / 0050156; and U.S. Patent Application Publication No. 2009 / 0044808.

[0082] Noise table of existing masks (ISO 17510-2:2007, 10cmH2O pressure 1m)

[0083]

[0084] (*One sample only, measured at 10 cmH2O in CPAP mode using the test method specified in ISO 3744) The following lists the sound pressure values ​​for various objects

[0085]

[0086] 2.2.4 Screening, diagnosis and monitoring systems

[0087] Polysomnography (PSG) is a conventional system for diagnosing and monitoring cardiopulmonary diseases, and usually involves clinical experts to apply the system. PSG usually involves placing 15 to 20 contact sensors on the patient to record various body signals, such as electroencephalogram (EEG), electrocardiogram (ECG), electrooculogram (EOG), electromyogram (EMG), etc. PSG for sleep-disordered breathing involves observing the patient for two nights in the clinic, one night for pure diagnosis and the second night for clinician titration of treatment parameters. Therefore, PSG is expensive and inconvenient. In particular, it is not suitable for home screening / diagnosis / monitoring of sleep-disordered breathing.

[0088] Screening and diagnosis generally describe the identification of a condition from its signs and symptoms. Screening typically produces a true / false result, indicating whether a patient's SDB is severe enough to warrant further investigation, while diagnosis can yield clinically actionable information. Screening and diagnosis tend to be one-time procedures, while monitoring progression can continue indefinitely. Some screening / diagnostic systems are suitable for screening / diagnosis only, while others can also be used for monitoring.

[0089] A clinical specialist may be able to adequately screen, diagnose, or monitor a patient based on visually observed PSG signals. However, there are situations where a clinical specialist may not be available or may not be affordable. Different clinical specialists may disagree on a patient's condition. Furthermore, a given clinical specialist may apply different criteria at different times. 3 Summary of the invention

[0090] The present technology is intended to provide medical devices for screening, diagnosing, monitoring, ameliorating, treating or preventing respiratory disorders with improved one or more of comfort, cost, efficacy, ease of use and manufacturability.

[0091] A first aspect of the present technology relates to a device for screening, diagnosing, monitoring, ameliorating, treating or preventing a respiratory disorder.

[0092] Another aspect of the present technology relates to methods for screening, diagnosing, monitoring, ameliorating, treating or preventing breathing disorders.

[0093] One aspect of some forms of the present technology is to provide methods and / or apparatus for improving patient compliance with respiratory therapy.

[0094] One aspect of some forms of the present technology is a medical device that is easy to use, for example, by a person without medical training, by a person with limited dexterity, vision, or by a person with limited experience in using medical devices of this type.

[0095] One aspect of one form of the present technology is a portable RPT device that can be carried by a person (e.g., within the person's home).

[0096] One aspect of one form of the present technology is a medical device that can be cleaned in a patient's home, for example, in soapy water, without the need for specialized cleaning equipment.

[0097] Another aspect of the present technology relates to a patient interface and a ventilation system for providing respiratory therapy to a patient, the patient interface having a therapeutic gas flow pressurized to a pressure above ambient pressure, the ventilation system configured to discharge the gas flow from a volume within the patient interface to the atmosphere, the gas flow being continuously vented to the atmosphere during the patient's breathing cycle.

[0098] Another aspect of the present technology relates to a ventilation system for use with a patient interface for providing respiratory therapy having a therapeutic flow pressurized to above ambient pressure to a patient throughout the patient's respiratory cycle, such as via a respiratory pressure therapy device, the ventilation system being configured to discharge a ventilation flow of gas to the atmosphere. The ventilation flow can be continuous throughout the patient's respiratory cycle. The ventilation system includes a ventilation housing having a first end and a second end aligned along a longitudinal axis of the ventilation housing and at least one exhaust orifice configured to discharge exhaust gas to the atmosphere; a membrane positioned within the ventilation housing, the membrane having a first end, a second end, and a movable portion, the first end and the second end of the membrane being spaced apart along the longitudinal axis of the membrane aligned with the longitudinal axis of the ventilation housing, the movable portion of the membrane being radially spaced from a surface of the ventilation housing interior facing the membrane to form an exhaust flow channel between the movable portion and the membrane-facing surface, the exhaust flow channel being configured to allow exhaust gas from the volume to flow through the exhaust flow channel via the at least one exhaust orifice to the atmosphere during use.

[0099] 3.1 Ventilation structure with inlet, outlet and exhaust opening

[0100] Another aspect of the present technology relates to a ventilation system for use with a patient interface, the ventilation system being used to provide a therapeutic gas flow pressurized to above ambient pressure within a therapeutic pressure range to a patient for respiratory therapy. The therapeutic gas flow can be pressurized by a respiratory pressure therapy device and can be provided to the patient throughout the patient's respiratory cycle. The ventilation system can be configured to provide a ventilation gas flow to discharge exhaust gas exhaled by the patient from a pressurized volume. The ventilation gas flow can be continuous throughout the patient's respiratory cycle. The ventilation system can include: a ventilation housing comprising an inlet configured to receive a gas flow from the respiratory pressure therapy device, an outlet configured to supply a therapeutic gas flow to the patient interface, and at least one exhaust orifice configured to discharge the exhaust gas to the atmosphere, the at least one exhaust orifice being sized and shaped to maintain a therapeutic pressure in the plenum during use; and a membrane positioned within the ventilation housing, the membrane having a first end and a second end spaced apart along a longitudinal axis of the membrane, the membrane having a movable portion positioned between the first end of the membrane and the second end of the membrane and about the longitudinal axis. The movable portion of the membrane may be radially spaced from a membrane-facing surface within the ventilation housing relative to the longitudinal axis of the membrane to form an exhaust flow channel between the movable portion of the membrane and the membrane-facing surface, the exhaust flow channel being configured to allow gas to flow from the volume through the exhaust flow channel to the atmosphere via the at least one exhaust orifice during use. The movable portion of the membrane may be elastically deformable and configured to move radially relative to the membrane-facing surface in response to a pressure differential between an inner side of the membrane and an outer side of the membrane to vary a cross-sectional area of ​​the exhaust flow channel and regulate ventilation airflow over a therapeutic pressure range.

[0101] According to another aspect of the present technology, a patient interface is provided, comprising: a plenum chamber that at least partially forms a volume that can be pressurized to a therapeutic pressure of at least 6 cmH2O above ambient air pressure throughout the patient's breathing cycle in use, the plenum chamber including a plenum chamber inlet port, the plenum chamber inlet port being sized and structured to receive a therapeutic airflow for breathing by the patient; a seal-forming structure that is constructed and arranged to seal with an area of ​​the patient's face surrounding an entrance to the patient's airway, the seal-forming structure having holes therein so that during use the therapeutic airflow is delivered to at least the entrance of the patient's nostrils, the seal-forming structure being constructed and arranged to maintain the therapeutic pressure in the plenum chamber during the patient's breathing cycle in use; a positioning and stabilizing structure that is configured to maintain the seal-forming structure in a therapeutically effective position on the patient's head; and a ventilation structure that is configured to discharge a ventilation airflow to the atmosphere, the ventilation airflow being continuous throughout the patient's breathing cycle. The ventilation structure comprises: a ventilation housing comprising an inlet configured to receive an airflow from a respiratory pressure therapy device, an outlet configured to supply the therapeutic airflow to an inlet port of the plenum chamber, and at least one exhaust orifice configured to discharge the ventilation airflow to the atmosphere, the at least one exhaust orifice being sized and shaped to maintain a therapeutic pressure in the plenum chamber during use; and a membrane positioned within the ventilation housing, the membrane having a first end and a second end spaced apart along a longitudinal axis of the membrane, the membrane having a movable portion positioned between the first end and the second end of the membrane and about the longitudinal axis; wherein the movable portion of the membrane is radially spaced from a surface facing the membrane interior of the ventilation housing relative to the longitudinal axis of the membrane, to form an exhaust flow channel between the movable portion of the membrane and the surface facing the membrane, the exhaust flow channel being configured to allow gas to flow from the volume through the exhaust flow channel via the at least one exhaust orifice to the atmosphere during use, wherein the movable portion of the membrane is elastically deformable and is configured to move radially relative to the surface facing the membrane in response to a pressure differential between the inner side of the membrane and the outer side of the membrane to change the cross-sectional area of ​​the exhaust flow channel and regulate ventilation airflow throughout the therapeutic pressure range; and wherein the patient interface is configured to allow the patient to breathe from the surrounding environment through their mouth in the absence of a flow of pressurized air through the inlet port of the inflation chamber, or the patient interface is configured so that the patient's mouth is uncovered.

[0102] In examples of the above aspects, (a) the movable portion of the membrane may be substantially cylindrical or frustoconical; the movable portion of the membrane may be substantially cylindrical; (c) the vent housing may include a first end and a second end aligned along the longitudinal axis of the vent housing, the longitudinal axis of the membrane being aligned with the longitudinal axis of the vent housing; (d) the longitudinal axis of the membrane may be aligned substantially parallel to the direction of airflow through the vent housing from the first end of the vent housing to the second end of the vent housing; (e) the movable portion of the membrane may include one or more walls, the one or more walls aligned parallel to the direction of airflow through the vent housing from the first end of the vent housing to the second end of the vent housing; (f) the movable portion of the membrane may include a cylindrical wall having an axis aligned parallel to the direction of airflow through the vent housing from the first end of the vent housing to the second end of the vent housing; (g) the vent structure may include a membrane support member, the membrane being supported on the membrane support member; (h) the membrane may be joined to the membrane support member at the first end of the membrane; (i) the membrane support member may be configured to be connected to the vent housing; (j) the movable portion of the membrane may be formed of silicone rubber; (k) the vent housing may include a first housing member at a first end of the vent housing and a second housing member at a second end of the vent housing, the first housing member and the second housing member being configured to be connected together; (l) the first housing member may include an inlet connection portion configured to connect the vent structure fluid to a supply conduit; (m) the inlet connection portion may be provided at or near the first end of the first housing portion; (n) the inlet connection portion may include a bayonet fitting configured to for engaging a corresponding fitting on the supply conduit; (o) the second shell member may include an outlet connection portion, which is configured to connect the ventilation structure fluid to a patient interface or to a tube configured to be connected to the patient interface; (p) the outlet connection portion may be configured to be connected to a patient interface or to a tube configured to be connected to a patient interface; (q) the outlet connection portion may include an internal threaded portion, which is configured to engage a corresponding threaded portion of the patient interface or the patient interface tube; and / or (r) the exhaust flow channel may occupy a continuous space around the entire circumference of the ventilation shell.

[0103] In a further example of the above aspects, (a) the vent structure may include a damping structure, which is configured to damp vibrations of the movable part of the membrane; (b) the damping structure may include a damping chamber within the vent housing, which is configured to damp vibrations of the movable part of the membrane; (c) the vent housing may at least partially form the damping chamber; (d) one of the inner side and the outer side of the movable part of the membrane may face the membrane-facing surface, and the other of the inner side and the outer side of the movable part of the membrane may at least partially form the damping chamber; (e) the damping chamber may be in fluid connection with the pressurized volume in use. (f) the vent structure may be configured so that movement of the movable portion of the membrane increases or decreases the volume of the damping chamber; (g) the vent housing and the damping chamber may be configured to damp vibrations of the movable portion of the membrane by limiting the exchange of gas between the damping chamber and the pressurized volume; (h) the vent structure may include at least one damping orifice through which gas can flow into and out of the damping chamber from the pressurized volume, the damping orifice preventing the exchange of gas between the damping chamber and the pressurized volume; (i) the vent structure may include a plurality of damping orifices through which gas can flow into and out of the damping chamber from the pressurized volume, the plurality of damping orifices together preventing the damping chamber from flowing into and out of the pressurized volume (j) the exhaust flow channel may include an area having a smaller cross-sectional area than adjacent areas of the exhaust flow channel; (k) the exhaust flow channel may include a restriction forming an area having a smaller cross-sectional area than adjacent areas; (l) the membrane-facing surface may be proximal to the movable portion of the membrane at the location of the restriction; (m) the membrane-facing surface may include a restrictor portion forming the restriction in the exhaust flow channel; (n) the membrane-facing surface may include a contoured surface forming the restrictor portion; (o) the restrictor portion may include ribs in the membrane-facing surface; (p) the restrictor portion may include an area of ​​increased material thickness domain; (q) the restrictor portion may be centrally located between the first end of the membrane and the second end of the membrane; (r) the damping chamber may include a first end adjacent to the first end of the membrane and a second end adjacent to the second end of the membrane, and the restriction portion in the exhaust flow channel is centrally aligned between the first end of the damping chamber and the second end of the damping chamber; (s) the ventilation housing may be configured to reduce vibration of the movable portion of the membrane at a vibration mode higher than the first vibration mode; (t) the damping chamber may be further defined by one or more walls of the second housing member; and / or (u) the damping chamber may be further defined by one or more walls of the membrane support member.

[0104] In a further example of the above aspects, (a) the vent housing may be configured to limit movement of the movable portion of the membrane toward the surface facing the membrane; (b) the vent housing may be configured to contact an end of the membrane and prevent the end of the membrane from moving toward the surface facing the membrane; (c) the vent housing may include at least one protrusion, the at least one protrusion being configured to contact the end of the membrane and limit movement of the end of the membrane toward the surface facing the membrane; (d) the at least one protrusion may be positioned outside the exhaust flow channel; and / or (e) the vent housing may include a plurality of protrusions and a plurality of damping orifices formed between the plurality of protrusions, gas being able to flow from the volume into and out of the damping chamber through the damping orifices, the damping orifices preventing gas exchange between the damping chamber and the volume to damp vibrations of the movable portion of the membrane.

[0105] In further examples of the above aspects, (a) the ventilation airflow may flow radially outward at or near the inlet of the exhaust flow passage; (b) the ventilation airflow may change direction from the radial direction to an axial direction aligned with the longitudinal axis of the ventilation structure when passing through the inlet of the exhaust flow passage; (c) the ventilation housing may include a circular surface at or near the inlet of the exhaust flow passage; (d) the circular surface may facilitate the change in direction of the ventilation airflow at or near the inlet of the exhaust flow passage; (e) the ventilation housing may include a plurality of exhaust apertures; (f) the exhaust apertures may be spaced around the circumference of the ventilation housing; (g) the ventilation housing may include at least one diffuse exhaust aperture and at least one non-diffuse exhaust aperture; (h) the vent housing may include a plurality of diffuse exhaust apertures and a plurality of non-diffuse exhaust apertures; (i) the at least one diffuse exhaust aperture and the at least one non-diffuse exhaust aperture may be spaced apart along the longitudinal axis of the vent housing; (j) the diffuse exhaust aperture may be located at or near the first end of the vent housing; (k) the non-diffuse exhaust aperture may be centrally located between the first end of the vent housing and the second end of the vent housing; (l) the at least one diffuse exhaust aperture may open in a lateral direction; (m) the at least one non-diffuse exhaust aperture may open in a lateral direction relative to the vent housing; (n) the vent structure may include a diffuser member configured to diffuse and / or audibly shield gas contacting the diffuser member during use; (o) the diffuser member may be positioned in series with the at least one diffuse exhaust orifice so that gas flowing through the at least one diffuse exhaust orifice is required to flow through the diffuser member; (p) the vent structure may provide a diffused vent flow path through which gas can be ventilated through the diffuser member and the at least one diffuse exhaust orifice; (q) the vent structure may provide an undiffused exhaust flow path through which gas can be ventilated The flow path is vented through the at least one undiffused exhaust orifice; (r) the vent structure can be configured to allow gas to flow through the at least one undiffused exhaust orifice in the event that the gas is unable to flow through the at least one diffuse exhaust orifice; (s) the vent structure can be configured to require the airflow to change direction to flow through the at least one undiffused exhaust orifice to a greater extent than through the diffuse exhaust orifice; and / or (t) the vent structure can be configured to require the airflow to change direction to flow through the undiffused exhaust orifice to a sufficient extent that a majority of the exhaust flow passes through the diffuser member and through the diffuse exhaust orifice unless the diffuser member becomes blocked.

[0106] In a further example of the above aspects, (a) the ventilation structure may include an exhaust orifice member, the exhaust orifice member including the at least one exhaust orifice; (b) the exhaust orifice member may include multiple exhaust orifices; (c) the exhaust orifice member may be configured to be connected to the first shell member; (d) the exhaust orifice member may be formed in the shape of a ring; (e) the exhaust orifice member may include multiple exhaust orifices spaced around the circumference of the ring; (f) the at least one diffused exhaust orifice may be provided at or near the first end of the exhaust orifice member; (g) the at least one non-diffused exhaust orifice may be provided at or near the second end of the exhaust orifice member opposite to the first end of the exhaust orifice member; (h) the diffuser member may be retained in the ventilation structure by the exhaust orifice member; and / or (i) the diffuser member may be accommodated between the exhaust orifice member and the first shell member.

[0107] In further examples of the above aspects, (a) the movable portion of the membrane may be positioned radially outward from the membrane-facing surface relative to the longitudinal axis of the membrane; (b) the movable portion of the membrane may be configured to move inward to restrict ventilation airflow; (c) the movable portion of the membrane may be configured to contract to move radially inward toward the membrane-facing surface; (d) the membrane-facing surface may be disposed on an outer surface of the first shell member, the outer surface being located within the ventilation shell; (e) the first shell member may include a shaft configured to protrude from a first end of the first shell member to an interior of the ventilation structure, the membrane-facing surface being disposed on an outer surface of the shaft, being located within the first shell member (f) the shaft may be centrally located within the breather housing; (g) the shaft may be aligned with a longitudinal axis of the breather housing; (h) the circular surface at or near the inlet of the exhaust flow passage may be a fillet on the periphery of the first housing member; (i) the circular surface may be provided on the shaft at the second end of the first housing member; (j) the breather housing may include a plurality of protrusions and a plurality of damping orifices may be defined between the plurality of protrusions; (k) the at least one protrusion may be provided on the second housing member; (l) the at least one protrusion may be located inwardly of the membrane; (m) the at least one protrusion may protrude toward the first end of the breather housing. (n) the second shell member may include an inwardly extending membrane retaining flange, the at least one protrusion protruding axially on the membrane retaining flange toward the first end of the vent shell; (o) the at least one protrusion may contact the inner surface of the membrane at the second end of the membrane; (p) the first shell member may include an outwardly extending flange located on the shaft, the outwardly extending flange being located at or near the first end of the first shell member; (q) the vent orifice member may be configured to be connected to an outwardly extending flange on the first shell member facing the second end of the first shell member; (r) the membrane support may include a connecting portion for connecting to the vent shell; (s) the connecting portion can be configured to be connected directly or indirectly to the vent housing; (t) the connecting portion can be cylindrical and configured to fit around the exterior of the second housing member; (u) the connecting portion can be concentric with the membrane; (v) the membrane support can include a membrane support flange formed as a flange extending inwardly from an interior of the connecting portion of the membrane support; (w) the membrane can be molded to the membrane support flange; (x) the membrane support flange can be spaced apart from an end of the connecting portion; (y) the vent orifice member and membrane support can be configured to be connected together to connect the first housing member and the second housing member; (z) the connecting portion of the membrane support can be configured to be connected to the vent orifice member;(aa) the connection portion of the membrane support may be configured to be press-fitted to an exterior of the vent member; and / or (bb) the membrane support flange may be located between the vent member and the second shell member when the membrane support is connected to both the vent member and the second shell member.

[0108] In further examples of the above aspects, (a) the movable portion of the membrane may be supported on the interior of the membrane-facing surface; (b) the movable portion of the membrane may be configured to move outward to restrict ventilation airflow; (c) the movable portion of the membrane may be configured to expand to move the membrane-facing surface outward; (d) the membrane-facing surface may be disposed on the interior surface of the first shell member; (e) the membrane-facing surface may be cylindrical or frustoconical; (f) the membrane support may include a baffle portion; (g) the baffle portion may be cylindrical; (h) the baffle portion may be concentric with the movable portion of the membrane; (i) the baffle portion may be disposed on the interior of the movable portion of the membrane; (j) the The baffle portion may have a first end connected to the movable portion of the membrane at the first end of the membrane and a second end disposed at or near the second end of the membrane; (k) the baffle portion may include an outwardly extending flange at the second end of the baffle portion; (l) the circular surface at or near the inlet of the exhaust flow channel may be a fillet disposed at the second end of the membrane support; (m) the circular surface may be disposed on the outwardly extending flange of the baffle portion of the membrane support; (n) the damping chamber may be partially defined by the baffle portion of the membrane support; (o) the damping chamber may be partially defined by the outwardly extending flange of the baffle portion; (p) the at least a protrusion may be provided on the first shell member; (q) the at least one protrusion may protrude radially inwardly from the cylindrical or conical surface of the first shell member; (r) the at least one protrusion may contact the outer surface of the membrane at the second end of the membrane; (s) the first shell member may include at least one intermediate exhaust orifice upstream of the diffuser member; (t) the diffuser member may be substantially cylindrical and positioned above the intermediate exhaust orifice to diffuse and / or audibly shield the ventilation airflow contacting the diffuser member during use; (u) the second shell member may include a diffuser retaining portion; (v) the diffuser retaining portion may include a portion configured to fit over the first shell member; a cylindrical sleeve on a shell member; (w) the first shell member may be substantially cylindrical and have a second shell member connecting portion at a second end of the first shell member and a diffuser support flange at a second end of the first shell member; (x) a diffuser may be retained in a diffuser passage between the diffuser support flange of the first shell member, the second shell member connecting portion of the first shell member, and the diffuser retaining portion of the second shell member; (y) the at least one exhaust aperture may be disposed in the diffuser retaining portion of the second shell member or may be formed by a gap between the diffuser retaining portion of the second shell member and the diffuser support flange of the first shell member;and / or (z) a plurality of exhaust apertures may be provided in the diffuser retaining portion of the second housing member and / or in a gap between the diffuser retaining portion of the second housing member and the diffuser support flange of the first housing member.;

[0109] 3.2 Ventilation Structure Configured to Limit Movement of the Second End of the Movable Membrane

[0110] Another aspect of the present technology relates to a ventilation system for use with a patient interface, the ventilation system being used to provide a therapeutic gas flow pressurized to above ambient pressure within a therapeutic pressure range to a patient for respiratory therapy. The therapeutic gas flow can be pressurized by a respiratory pressure therapy device and can be provided throughout the patient's breathing cycle. The ventilation system can be configured to provide a ventilation gas flow to discharge gas exhaled by the patient from a pressurized volume. The ventilation gas flow can be continuous throughout the patient's breathing cycle. The ventilation system can include: a ventilation housing comprising at least one exhaust orifice configured to allow exhaust gas to be discharged from the pressurized volume to the atmosphere; and a membrane positioned within the ventilation housing, the membrane having a first end and a second end spaced apart along a longitudinal axis of the membrane, the membrane having a movable portion positioned between the first end of the membrane and the second end of the membrane about the longitudinal axis. The movable portion of the membrane can be radially spaced from a membrane-facing surface within the ventilation housing relative to the longitudinal axis of the membrane to form an exhaust flow channel between the movable portion of the membrane and the membrane-facing surface, the exhaust flow channel being configured to allow exhaust gas to flow from the pressurized volume through the exhaust flow channel to the atmosphere via the at least one exhaust orifice during use. The movable portion of the membrane can be elastically deformable and configured to move radially relative to the membrane-facing surface in response to a pressure differential between an inner side of the membrane and an outer side of the membrane so as to change the cross-sectional area of ​​the exhaust flow channel and regulate ventilation airflow over the entire therapeutic pressure range. The ventilation housing can be configured to limit movement of the second end of the membrane toward the membrane-facing surface.

[0111] According to another aspect of the present technology, a patient interface is provided, comprising: a plenum chamber that at least partially forms a volume that can be pressurized to a therapeutic pressure of at least 6 cmH2O above ambient air pressure throughout the patient's breathing cycle in use, the plenum chamber including a plenum chamber inlet port that is sized and structured to receive a therapeutic airflow for breathing by the patient from the volume; a seal-forming structure that is constructed and arranged to seal with an area of ​​the patient's face surrounding an entrance to the patient's airway, the seal-forming structure having holes therein such that during use the therapeutic airflow is delivered to at least the entrance to the patient's nostrils, the seal-forming structure being constructed and arranged to maintain the therapeutic pressure in the plenum chamber during the patient's breathing cycle in use; a positioning and stabilizing structure that is configured to maintain the seal-forming structure in a therapeutically effective position on the patient's head; and a ventilation structure that is configured to discharge a ventilation airflow to the atmosphere, the ventilation airflow being continuous throughout the patient's breathing cycle. 18. The vent structure comprises: a vent housing comprising at least one exhaust orifice for exhausting gas to the atmosphere, the at least one exhaust orifice being sized and shaped to maintain a therapeutic pressure in the plenum during use; a membrane positioned within the vent housing, the membrane having a first end and a second end spaced apart along a longitudinal axis of the membrane, the membrane having a movable portion positioned between the first end of the membrane and the second end of the membrane about the longitudinal axis; wherein the movable portion of the membrane is radially spaced from a membrane-facing surface of an interior of the vent housing relative to the longitudinal axis of the membrane to form an exhaust flow channel between the movable portion of the membrane and the membrane-facing surface, the exhaust flow channel being configured to allow exhaust gas from the pressurized volume to pass through the exhaust flow channel during use. the ventilation housing comprising a first end and a second end of the membrane, wherein the membrane is secured in position within the housing and the second end of the membrane is secured to the ventilator ...

[0112] In examples of the above aspects, (a) the vent housing may contact the second end of the membrane and prevent the second end of the membrane from moving toward the surface facing the membrane; (b) the vent housing may include at least one protrusion, the at least one protrusion being configured to contact the second end of the membrane and limit movement of the second end of the membrane toward the surface facing the membrane; (c) the movable portion of the membrane may be substantially cylindrical or frustoconical; (d) the vent housing may include a first end and a second end aligned along a longitudinal axis, the longitudinal axis of the membrane being aligned with the longitudinal axis of the vent housing; (e) the longitudinal axis of the membrane may be substantially parallel to the longitudinal axis from the first end of the vent housing to the second end of the vent housing. (f) the movable portion of the membrane may include one or more walls, the one or more walls being aligned parallel to the airflow through the ventilation housing from the first end of the ventilation housing to the second end of the ventilation housing; (g) the movable portion of the membrane may include a cylindrical wall, the cylindrical wall having an axis aligned parallel to the direction of the airflow through the ventilation housing from the first end of the ventilation housing to the second end of the ventilation housing; (h) the ventilation structure may include a membrane support member, the membrane being supported on the membrane support member; (i) the membrane may be joined to the membrane support member at the first end of the membrane; (j) the The membrane support may be configured to be connected to the ventilation housing; (k) the movable portion of the membrane may be formed of silicone rubber; (l) the ventilation housing may include an inlet for receiving an airflow from a respiratory pressure therapy device and an outlet for supplying the therapeutic airflow to a patient interface; (m) the ventilation housing may include a first housing member at a first end of the ventilation housing and a second housing member at a second end of the ventilation housing, the first housing member and the second housing member being configured to be connected together; (n) the first housing member may include the inlet and the inlet connecting portion, which are configured to connect the ventilation structure fluid to a supply conduit; (o) the inlet connecting portion may be provided on the first housing at or near the first end of the body portion; (p) the inlet connection portion may include a bayonet fitting configured to engage a corresponding fitting on the supply conduit; (q) the second shell member may include the outlet and the outlet connection portion, which are configured to connect the ventilation structure fluid to the patient interface; (r) the outlet connection portion may be configured to be connected to the patient interface or to be connected to a tube of the patient interface; (s) the outlet connection portion may include an internal threaded portion configured to engage a corresponding threaded portion of the patient interface or to be configured to be connected to a tube on the patient interface; and / or (t) the exhaust flow channel may occupy a continuous space around the entire circumference of the ventilation shell.

[0113] In a further example of the above aspects, (a) the vent structure may include a damping structure configured to damp vibrations of the movable portion of the membrane; (b) the damping structure may include a damping chamber within the vent housing; (c) the vent housing may at least partially form the damping chamber; (d) one of the inner side and the outer side of the movable portion of the membrane may face the membrane-facing surface, and the other of the inner side and the outer side of the movable portion of the membrane may at least partially form the damping chamber; (e) the damping chamber may be in fluid communication with the pressurized volume in use; (f) the vent structure may be configured to (g) the vent housing and the damping chamber may be configured to damp vibrations of the movable portion of the diaphragm by limiting the exchange of gas between the damping chamber and the pressurized volume; (h) the vent structure may include at least one damping hole through which gas can flow into and out of the damping chamber from the pressurized volume, the damping hole preventing the exchange of gas between the damping chamber and the pressurized volume; (i) the vent structure may include a plurality of damping orifices through which gas can flow into and out of the damping chamber from the pressurized volume, the plurality of damping orifices together preventing the exchange of gas between the damping chamber and the pressurized volume. (j) the exhaust flow channel may include an area having a smaller cross-sectional area than an adjacent area of ​​the exhaust flow channel; (k) the exhaust flow channel may include a restriction forming an area having a smaller cross-sectional area; (l) the membrane-facing surface may be proximal to the movable portion of the membrane at the location of the restriction; (m) the membrane-facing surface may include a restrictor portion forming a restriction in the exhaust flow channel; (n) the membrane-facing surface may include a contoured surface forming the restrictor portion; (o) the restrictor portion may include ribs in the membrane-facing surface; (p) the restrictor portion may include a portion of increased material thickness. area; (q) the restrictor portion may be centrally located between the first end of the membrane and the second end of the membrane; (r) the damping chamber may include a first end adjacent the first end of the membrane and a second end adjacent the second end of the membrane; (s) the restriction in the exhaust flow channel may be centrally aligned between the first end of the damping chamber and the second end of the damping chamber; (t) the ventilation housing may be configured such that vibration of the movable portion of the membrane occurs primarily in a first vibration mode; (u) the damping chamber may be further defined by one or more walls of the second housing member; and / or (v) the damping chamber may be further defined by one or more walls of the membrane support member.

[0114] In further examples of the above aspects, (a) the exhaust flow may flow radially outward at or near the inlet of the exhaust flow passage; (b) the ventilation airflow may be changed from a radial direction aligned with the longitudinal axis of the ventilation structure to an axial direction at or near the inlet of the exhaust flow passage; (c) the ventilation housing may include a circular surface at or near the inlet of the exhaust flow passage; (d) the circular surface may be configured to facilitate changing the direction of the ventilation airflow at or near the inlet of the exhaust flow passage; (e) the ventilation housing may include a plurality of exhaust apertures; (f) the exhaust apertures may be spaced around the circumference of the ventilation housing; (g) the ventilation housing may include a plurality of exhaust apertures; (g) the exhaust apertures may be spaced around the circumference of the ventilation housing; (h) the vent housing may include a plurality of diffuse exhaust apertures and a plurality of non-diffused exhaust apertures; (i) the at least one diffuse exhaust aperture and the at least one non-diffused exhaust aperture may be spaced apart along the longitudinal axis of the vent housing; (j) the diffuse exhaust aperture may be located at or near the first end of the vent housing; (k) the non-diffused exhaust aperture may be centrally located between the first end of the membrane and the second end of the vent housing; (l) the at least one diffuse exhaust aperture may open in a transverse direction; (m) the at least one non-diffused exhaust aperture may open in a partially transverse direction and (n) the vent structure may include a diffuser member configured to diffuse and / or audibly shield gas contacting the diffuser member during use; (o) the diffuser member may be positioned in series with the at least one diffuse exhaust orifice so that gas flowing through the at least one diffuse exhaust orifice is required to flow through the diffuser member; (p) the vent structure may provide a diffused vent flow path through which gas can be ventilated through the diffuser member and the at least one diffuse exhaust orifice; (q) the vent structure may provide an undiffused exhaust flow path through which gas can flow (r) the vent structure can be configured to allow gas to flow through the at least one undiffused exhaust orifice in the event that the gas is unable to flow through the at least one diffuse exhaust orifice; (s) the vent structure can be configured to require the airflow to change direction to flow through the at least one undiffused exhaust orifice to a greater extent than through the diffuse exhaust orifice; and / or (t) the vent structure can be configured to require the airflow to change direction to flow through the undiffused exhaust orifice to a sufficient extent that a majority of the exhaust flow passes through the diffuser member and through the diffuse exhaust orifice unless the diffuser member becomes blocked.

[0115] In a further example of the above aspects, (a) the ventilation structure may include an exhaust orifice member, the exhaust orifice member including the at least one exhaust orifice; (b) the exhaust orifice member may include multiple exhaust orifices; (c) the exhaust orifice member may be configured to be connected to the first shell member; (d) the exhaust orifice member may be formed in the shape of a ring; (e) the exhaust orifice member may include multiple exhaust orifices spaced around the circumference of the ring; (f) the at least one diffused exhaust orifice may be provided at or near the first end of the exhaust orifice member; (g) the at least one non-diffused exhaust orifice may be provided at or near the second end of the exhaust orifice member opposite to the first end of the exhaust orifice member; (h) the diffuser member may be retained in the ventilation structure by the exhaust orifice member; and / or (i) the diffuser member may be accommodated between the exhaust orifice member and the first shell member.

[0116] In a further example of the above aspects, (a) the movable portion of the membrane may be positioned radially outward from the membrane-facing surface relative to the longitudinal axis of the membrane; (b) the movable portion of the membrane may be configured to move inwardly to restrict ventilation airflow; (c) the movable portion of the membrane may be configured to contract to move inwardly toward the membrane-facing surface; (d) the membrane-facing surface may be disposed on an outer surface of the first shell member located within the ventilation shell; (e) the at least one protrusion may be disposed outside the exhaust flow channel; and (f) the ventilation shell may include a plurality of protrusions and a plurality of damping orifices, a plurality of damping orifices being defined between the plurality of protrusions, through which gas can flow into and out of the pressurized volume. (i) the shaft may be aligned with the longitudinal axis of the vent housing; (j) the circular surface at or near the inlet of the exhaust flow channel may be a fillet on the outer periphery of the first housing member; (k) the circular surface may be provided at the second end of the first housing member. on the shaft; (l) the vent housing may include a plurality of protrusions, and a plurality of damping orifices may be defined between the plurality of protrusions; (m) the at least one protrusion may be disposed on the second housing member; (n) the at least one protrusion may be located within the membrane; (o) the at least one protrusion may protrude toward the first end of the vent housing; (p) the second housing member may include an inwardly extending membrane retaining flange, the at least one protrusion protruding axially toward the first end of the vent housing on the membrane retaining flange; (q) the at least one protrusion may contact an inner surface of the membrane at the second end of the membrane; (r) the first housing member may include an outwardly extending flange on the shaft, the flange located at or near the first end of the first shell member; (s) the vent member may be configured to be connected to an outwardly extending flange on the first shell member facing the second end of the first shell member; (t) the membrane support may include a connecting portion for connecting to the vent housing; (u) the connecting portion may be configured to connect directly or indirectly to the vent housing; (v) the connecting portion may be cylindrical and configured to fit around the exterior of the second shell member; (w) the connecting portion may be concentric with the membrane; (x) the membrane support may include a membrane support flange formed as a flange extending inwardly from an interior of the connecting portion of the membrane support; (y) the membrane may be molded to the membrane support flange;(z) the membrane support flange may be spaced apart from an end of the connecting portion; (aa) the vent member and the membrane support may be configured to be connected together to connect the first shell member and the second shell member; (ab) the connecting portion of the membrane support may be configured to be connected to the vent member; (ac) the connecting portion of the membrane support may be configured to form a press fit with the exterior of the vent member; and / or (ad) when the membrane support is connected to the vent member and the second shell member, the membrane support flange may be located between the vent member and the second shell member.

[0117] In further examples of the above aspects, (a) the movable portion of the membrane may be supported radially inwardly from the membrane-facing surface relative to the longitudinal axis of the membrane; (b) the movable portion of the membrane may be configured to move outwardly to restrict ventilation airflow; (c) the movable portion of the membrane may be configured to expand to move the membrane-facing surface outwardly; (d) the membrane-facing surface may be disposed on the inner surface of the first shell member; (e) the membrane-facing surface may be cylindrical or frustoconical; (f) the membrane support may include a baffle portion; (g) the baffle portion may be cylindrical; (h) the baffle portion may be concentric with the movable portion of the membrane; (i) the baffle portion may be disposed on the membrane (j) the baffle portion may have a first end connected to the movable portion of the membrane at the first end of the membrane and a second end disposed at or near the second end of the membrane; (k) the baffle portion may include an outwardly extending flange at the second end of the baffle portion; (l) the circular surface at or near the inlet of the exhaust flow channel may be a fillet disposed at the second end of the membrane support; (m) the circular surface may be disposed on the outwardly extending flange of the baffle portion of the membrane support; (n) the damping chamber may be partially defined by the baffle portion of the membrane support; (o) the damping chamber may be partially defined by the outwardly extending baffle portion of the membrane support (i) the first housing member may include a first housing member having a plurality of protrusions extending therefrom; (ii) the first housing member may include a plurality of protrusions extending therefrom; (iii) the first housing member may include a plurality of protrusions extending therefrom; (iv) the first housing member may include a plurality of protrusions extending therefrom; (v ... a cylindrical sleeve on the first shell member; (w) the first shell member may be substantially cylindrical and have a second shell member connecting portion at a second end of the first shell member and a diffuser support flange at a second end of the first shell member; (x) a diffuser may be retained in a diffuser passage between the diffuser support flange of the first shell member, the second shell member connecting portion of the first shell member, and the diffuser retaining portion of the second shell member; (y) the at least one exhaust aperture may be disposed in the diffuser retaining portion of the second shell member or may be formed by a gap between the diffuser retaining portion of the second shell member and the diffuser support flange of the first shell member;and / or (z) a plurality of exhaust apertures may be provided in the diffuser retaining portion of the second housing member and / or in a gap between the diffuser retaining portion of the second housing member and the diffuser support flange of the first housing member.;

[0118] 3.3 Ventilation structure with damping structure for damping membrane vibration

[0119] Another aspect of the present technology relates to a ventilation system for use with a patient interface, the ventilation system being configured to provide a therapeutic airflow pressurized to above ambient pressure within a therapeutic pressure range to a patient for respiratory therapy. The therapeutic airflow may be pressurized by a respiratory pressure therapy device and may be provided throughout the patient's respiratory cycle. The ventilation system may be configured to provide the ventilation airflow to discharge exhaled gas from a pressurized volume. The ventilation airflow may be continuous throughout the patient's respiratory cycle. The ventilation system may include: a ventilation housing including at least one exhaust orifice configured to allow exhaust gas to be discharged from the pressurized volume to the atmosphere; a membrane positioned within the ventilation housing, the membrane having a movable portion spaced from a membrane-facing surface within the ventilation housing to form an exhaust flow channel between the movable portion and the membrane-facing surface, the exhaust flow channel being configured to allow exhaust gas to flow from the pressurized volume to the atmosphere via the at least one exhaust orifice; and a damping structure configured to damp vibrations of the movable portion of the membrane, the damping structure comprising a damping chamber positioned within the ventilation housing. The movable portion of the membrane may be elastically deformable and configured to move relative to the membrane-facing surface in response to a pressure differential between a first side of the membrane and a second side of the membrane to change the cross-sectional area of ​​the exhaust flow channel and regulate ventilation airflow over a therapeutic pressure range. The first side of the movable portion of the membrane may face the membrane-facing surface, and the second side of the movable portion of the membrane may partially define a damping chamber.

[0120] A patient interface comprises: an inflatable chamber which at least partially forms a volume that can be pressurized to a therapeutic pressure of at least 6 cmH2O above ambient air pressure throughout the patient's breathing cycle in use, the inflatable chamber including a inlet port, the inlet port being sized and structured to receive a therapeutic airflow for breathing by the patient; a seal-forming structure which is constructed and arranged to seal with an area of ​​the patient's face surrounding an entrance to the patient's airway, the seal-forming structure having holes therein so that during use the therapeutic airflow is delivered to at least the entrance of the patient's nostrils, the seal-forming structure being constructed and arranged to maintain the therapeutic pressure in the inflatable chamber during the patient's breathing cycle in use; a positioning and stabilizing structure which is configured to maintain the seal-forming structure in a therapeutically effective position on the patient's head; and a ventilation structure for discharging a ventilation airflow to the atmosphere, the ventilation airflow being continuous throughout the patient's breathing cycle. The vent structure comprises: a vent housing comprising at least one exhaust aperture for exhausting gas to the atmosphere, the at least one exhaust aperture being sized and shaped to maintain a therapeutic pressure in the plenum during use; and a membrane positioned within the vent housing, the membrane having a movable portion spaced apart from a membrane-facing surface within the vent housing to form an exhaust flow channel between the movable portion of the membrane and the membrane-facing surface, the exhaust flow channel being configured to allow exhaust gas to flow from the pressurized volume to the atmosphere via the at least one exhaust aperture, a damping structure configured to damp vibrations of the movable portion of the membrane, the damping structure comprising a damping chamber positioned within the vent housing. ; wherein the movable portion of the membrane is elastically deformable and is configured to move relative to the membrane-facing surface in response to a pressure differential between a first side of the membrane and a second side of the membrane to change the cross-sectional area of ​​the exhaust flow channel and regulate ventilation airflow over the entire therapeutic pressure range; wherein the first side of the movable portion of the membrane faces the membrane-facing surface and the second side of the movable portion of the membrane partially defines the damping chamber; and wherein the patient interface is configured to allow the patient to breathe from the ambient environment through their mouth in the absence of a flow of pressurized air through the inlet port of the plenum chamber, or the patient interface is configured such that the patient's mouth is uncovered.

[0121] In examples of the above aspects, (a) the vent housing may partially define a damping chamber; (b) the damping chamber may be in fluid communication with the pressurized volume during use; (c) the vent structure may be configured such that movement of the movable portion of the membrane increases or decreases the volume of the damping chamber; (d) the vent housing and damping chamber may be configured to damp vibrations of the movable portion of the membrane by limiting the exchange of gas between the damping chamber and the pressurized volume; (e) the vent structure may include at least one damping orifice through which gas can flow from the pressurized volume into and out of the damping chamber, the damping orifice preventing the exchange of gas between the damping chamber and the pressurized volume; (f) the vent structure may include a plurality of damping orifices , gas can flow from the pressurized volume into and out of the damping chamber through these damping orifices, and the plurality of damping orifices together prevent gas exchange between the damping chamber and the pressurized volume; (g) the damping chamber may include a first end adjacent to the first end of the membrane and a second end adjacent to the second end of the membrane; (h) the exhaust flow channel may include a region having a smaller cross-sectional area than an adjacent region of the exhaust flow channel; (i) the exhaust flow channel may include a restriction forming a region having a smaller cross-sectional area; (j) the surface facing the membrane may be closest to the movable portion of the membrane at the restriction; (k) the restriction in the exhaust flow channel may be centrally aligned with the first end of the damping chamber. (i) the membrane-facing surface may include a restrictor portion forming a restriction in the exhaust flow channel; (ii) the membrane-facing surface may include a contoured surface forming the restrictor portion; (iii) the restrictor portion may include a rib in the membrane-facing surface; (iv) the restrictor portion may include an area of ​​increased material thickness; (v) the restrictor portion may be centrally located between the first end of the membrane and the second end of the membrane; (v) the damping chamber may include a first end adjacent to the first end of the membrane and a second end adjacent to the second end of the membrane, the restriction in the exhaust flow channel being located between the first end and the second end of the damping chamber. and a second housing member configured to connect the ventilation structure to the patient interface.and / or (v) the second housing member may include the outlet and the outlet connection portion configured to fluidly connect the ventilation structure to a patient interface; and / or (w) the exhaust flow channel may occupy a continuous space around the entire circumference of the ventilation housing.

[0122] 3.4 Ventilation housing that reduces vibration of the membrane in a mode higher than the first mode

[0123] Another aspect of the present technology relates to a ventilation system for use with a patient interface, the ventilation system being configured to provide a therapeutic airflow pressurized to above ambient pressure within a therapeutic pressure range to a patient for respiratory therapy. The therapeutic airflow can be pressurized by a respiratory pressure therapy device and can be provided throughout the patient's breathing cycle. The ventilation system can be configured to provide a ventilation airflow to discharge gas exhaled by the patient from a pressurized volume. The ventilation airflow can be continuous throughout the patient's breathing cycle. The ventilation system can include: a ventilation housing comprising at least one exhaust orifice configured to allow exhaust gas to be discharged from the pressurized volume to the atmosphere; and a membrane located within the ventilation housing, the membrane having a movable portion. The movable portion of the membrane can be spaced from a surface facing the membrane within the ventilation housing to form an exhaust flow channel between the movable portion of the membrane and the surface facing the membrane, the exhaust flow channel being configured to allow exhaust gas to flow from the pressurized volume through the exhaust flow channel via the at least one exhaust orifice to the atmosphere. The movable portion of the membrane can be elastically deformable and configured to move relative to the membrane-facing surface in response to a pressure differential between a first side of the membrane and a second side of the membrane to vary the cross-sectional area of ​​the exhaust flow channel and regulate ventilation airflow over a therapeutic pressure range. The ventilation housing can be configured to reduce vibration of the movable portion of the membrane in a mode higher than the first vibration mode.

[0124] According to another aspect of the present technology, a patient interface is provided, comprising a plenum chamber that at least partially defines a pressurized volume of the patient interface, pressurizable to a therapeutic pressure of at least 6 cmH2O above ambient air pressure throughout the patient's breathing cycle in use, the plenum chamber including a plenum chamber inlet port sized and configured to receive a therapeutic flow of gas for breathing by the patient from the pressurized volume; a seal-forming structure constructed and arranged to form a seal with an area of ​​the patient's face surrounding an entrance to the patient's airway, the seal-forming structure having apertures therein such that the therapeutic flow of gas is delivered to at least the entrance to the patient's nares, the seal-forming structure constructed and arranged to maintain the therapeutic pressure in the plenum chamber during the patient's entire breathing cycle in use; a positioning and stabilizing structure that provides a force to maintain the seal-forming structure in a therapeutically effective position on the patient's head; a ventilation structure that allows a ventilation flow of gas to discharge exhaust gas exhaled by the patient from the pressurized volume to the surrounding environment, the ventilation flow being continuous throughout the patient's breathing cycle, the ventilation structure being sized and shaped to maintain the therapeutic pressure in the plenum chamber in use. The vent structure comprises: a vent housing including at least one exhaust aperture to allow exhaust gas to vent from the pressurized volume to the atmosphere; a membrane within the vent housing, the membrane having a movable portion; wherein the movable portion of the membrane is spaced from a membrane-facing surface within the vent housing to form an exhaust flow channel between the movable portion and the membrane-facing surface, the exhaust flow channel allowing exhaust gas to flow from the pressurized volume via the at least one exhaust aperture via the exhaust flow channel to the atmosphere during use; wherein the movable portion of the membrane is elastically deformable and is configured to move relative to the membrane-facing surface in response to a pressure differential between a first side of the membrane and a second side of the membrane to change the cross-sectional area of ​​the exhaust flow channel and regulate ventilation airflow over a therapeutic pressure range, wherein the vent housing is configured to reduce vibration of the movable portion of the membrane at a vibration mode higher than a first vibration mode; and wherein the patient interface is configured to allow the patient to breathe from the ambient environment through their mouth in the absence of pressurized air flow through the plenum inlet port, or the patient interface is configured such that the patient's mouth is uncovered.

[0125] In examples of the above aspects, (a) the vent structure may include a damping structure configured to damp vibrations of a movable portion of the membrane; (b) the damping structure may include a damping chamber within the vent housing; (c) the vent housing may partially define the damping chamber; (d) a first side of the movable portion of the membrane may face a surface of the membrane, and a second side of the movable portion of the membrane may partially define the damping chamber; (e) the damping chamber may be in fluid communication with the pressurized volume in use; (f) the vent structure may be configured such that movement of the movable portion of the membrane increases or decreases the volume of the damping chamber; and (g) the vent housing and damping chamber may be configured to damp vibrations of the pressurized volume by restricting gas between the damping chamber and the pressurized volume. (h) the vent structure may include at least one damping orifice through which gas can flow from the pressurized volume into and out of the damping chamber, the damping orifice preventing gas exchange between the damping chamber and the pressurized volume; (i) the vent structure may include a plurality of damping orifices through which gas can flow from the pressurized volume into and out of the damping chamber, the plurality of damping orifices together preventing gas exchange between the damping chamber and the pressurized volume; (j) the damping chamber may include a first end adjacent to the first end of the membrane and a second end adjacent to the second end of the membrane; (k) the exhaust flow channel may include a cross-sectional area having a smaller cross-sectional area than an adjacent area of ​​the exhaust flow channel (i) the exhaust flow channel may include a restriction forming an area having a smaller cross-sectional area; (ii) the membrane-facing surface may be proximate to the movable portion of the membrane at the location of the restriction; (iii) the membrane-facing surface may include a restrictor portion forming a restriction in the exhaust flow channel; (iv) the membrane-facing surface may include a contoured surface forming the restrictor portion; (v) the restrictor portion may include ribs in the membrane-facing surface; (v) the restrictor portion may include an area of ​​increased material thickness; (v) the restrictor portion may be centrally located between the first end of the membrane and the second end of the membrane; (v) the restriction in the exhaust flow channel may be located within the first end of the damping chamber. the first end of the ventilation structure and the second end of the damping chamber; (t) the ventilation housing may include an inlet for receiving an airflow from the respiratory pressure therapy device and an outlet for supplying the therapeutic airflow to the patient interface; (u) the ventilation housing may include a first housing member at the first end of the ventilation housing and a second housing member at the second end of the ventilation housing, the first housing member and the second housing member being configured to be connected together; (v) the first housing member may include the inlet and the inlet connecting portion configured to connect the ventilation structure fluid to the supply conduit; (w) the second housing member may include the outlet and the outlet connecting portion configured to connect the ventilation structure fluid to the patient interface;(x) The exhaust flow passage may occupy a continuous space around the entire circumference of the vent housing.

[0126] 3.5 Vented housing with trapped air cavity

[0127] Another aspect of the present technology relates to a ventilation system for use with a patient interface, the ventilation system for providing a therapeutic airflow pressurized to above ambient pressure within a therapeutic pressure range to a patient for respiratory therapy. The therapeutic airflow can be pressurized by a respiratory pressure therapy device and can be provided throughout the patient's breathing cycle. The ventilation system is configured to provide a ventilation airflow to discharge gas exhaled by the patient from a pressurized volume. The ventilation airflow can be continuous throughout the patient's breathing cycle. The ventilation system can include: a ventilation housing, which includes at least one exhaust orifice to allow exhaust gas to be discharged from the pressurized volume to the atmosphere; a membrane within the ventilation housing, the membrane having a movable portion, the movable portion having a first side and a second side; and a retention air cavity, which is within the ventilation housing on the first side of the movable portion of the membrane, the movable portion of the membrane at least partially defining the retention air cavity. The movable portion of the membrane may be spaced apart from a membrane-facing surface within the ventilation housing to form an exhaust flow channel on the second side of the membrane between the movable portion of the membrane and the membrane-facing surface, the exhaust flow channel allowing exhaust gas to flow from the pressurized volume via the exhaust flow channel to the atmosphere via the at least one exhaust orifice. The movable portion of the membrane may be elastically deformable and configured to move relative to the membrane-facing surface in response to a pressure differential between the first side of the membrane and the second side of the membrane to change a cross-sectional area of ​​the exhaust flow channel and regulate ventilation airflow over the entire therapeutic pressure range.

[0128] According to another aspect of the present technology, a patient interface is provided, comprising: a plenum chamber that at least partially forms a volume that can be pressurized to a therapeutic pressure of at least 6 cmH2O above ambient air pressure throughout the patient's breathing cycle in use, the plenum chamber including a plenum chamber inlet port, the plenum chamber inlet port being sized and structured to receive a therapeutic airflow for breathing by the patient; a seal-forming structure that is constructed and arranged to seal with an area of ​​the patient's face surrounding an entrance to the patient's airway, the seal-forming structure having holes therein so that during use the therapeutic airflow is delivered to at least the entrance of the patient's nostrils, the seal-forming structure being constructed and arranged to maintain the therapeutic pressure in the plenum chamber during the patient's breathing cycle in use; a positioning and stabilizing structure that is configured to maintain the seal-forming structure in a therapeutically effective position on the patient's head; and a ventilation structure that is configured to discharge a ventilation airflow to the atmosphere, the ventilation airflow being continuous throughout the patient's breathing cycle. The vent structure comprises: a vent housing including at least one exhaust orifice for exhausting gas to atmosphere, the at least one exhaust orifice being sized and shaped to maintain a therapeutic pressure in the plenum during use; a membrane positioned within the vent housing, the membrane having a movable portion having a first side and a second side; a trapped air cavity positioned within the vent housing on the first side of the movable portion of the membrane, the movable portion of the membrane at least partially forming the trapped air cavity; wherein the movable portion of the membrane is spaced from a membrane-facing surface of an interior of the vent housing so as to provide a space between the movable portion of the membrane and the membrane-facing surface on the second side of the membrane. an exhaust flow channel is formed thereon, the exhaust flow channel being configured to allow exhaust to flow from the pressurized volume via the at least one exhaust orifice to the atmosphere via the exhaust flow channel during use, wherein the movable portion of the membrane is elastically deformable and is configured to move relative to the surface facing the membrane in response to a pressure differential between the first side of the membrane and the second side of the membrane to change the cross-sectional area of ​​the exhaust flow channel and regulate the ventilation airflow throughout the therapeutic pressure range; and wherein the patient interface is configured to allow the patient to breathe from the surrounding environment through their mouth in the absence of a flow of pressurized air through the inlet port of the plenum chamber, or the patient interface is configured such that the patient's mouth is uncovered.

[0129] In examples of the above aspects, (a) the vent housing may partially define a trapped air cavity; (b) the trapped air cavity may include a damping chamber configured to damp vibrations of the movable portion of the membrane; (c) the vent housing may partially define the damping chamber; (d) one of the first side and the second side of the movable portion of the membrane may face the membrane-facing surface and the other of the first side and the second side of the movable portion of the membrane may partially define the damping chamber; (e) the damping chamber may be in fluid communication with the pressurized volume in use; (f) the vent structure may be configured such that movement of the movable portion of the membrane increases or decreases the volume of the damping chamber; (g) the vent housing and the damping chamber may be configured to damp vibrations of the pressurized volume by limiting the damping chamber from the pressurized volume. (h) the vent structure may include at least one damping orifice through which gas can flow from the pressurized volume into and out of the damping chamber, the damping orifice preventing gas exchange between the damping chamber and the pressurized volume; (i) the vent structure may include a plurality of damping orifices through which gas can flow from the pressurized volume into and out of the damping chamber, the plurality of damping orifices together preventing gas exchange between the damping chamber and the pressurized volume; (j) the damping chamber may include a first end adjacent to the first end of the membrane and a second end adjacent to the second end of the membrane; (k) the exhaust flow channel may include a region having a smaller diameter than an adjacent region of the exhaust flow channel. (i) an area of ​​a cross-sectional area; (ii) the exhaust flow channel may include a restriction forming an area of ​​smaller cross-sectional area; (iii) the membrane-facing surface may be proximate to the movable portion of the membrane at the location of the restriction; (iv) the membrane-facing surface may include a restrictor portion forming a restriction in the exhaust flow channel; (v) the membrane-facing surface may include a contoured surface forming the restrictor portion; (v) the restrictor portion may include ribs in the membrane-facing surface; (v) the restrictor portion may include an area of ​​increased material thickness; (v) the restrictor portion may be centrally located between the first end of the membrane and the second end of the membrane; (v) the restriction in the exhaust flow channel may be located at the first end of the damping chamber. The ventilation housing may include an inlet for receiving an airflow from a respiratory pressure therapy device and an outlet for supplying the therapeutic airflow to the patient interface; (u) the ventilation housing may include a first housing member at the first end of the ventilation housing and a second housing member at the second end of the ventilation housing, the first housing member and the second housing member being configured to be connected together; (v) the first housing member may include the inlet and the inlet connecting portion configured to connect the ventilation structure fluid to a supply conduit; (w) the second housing member may include the outlet and the outlet connecting portion configured to connect the ventilation structure fluid to the patient interface;(x) the vent housing may be configured such that vibration of the movable portion of the membrane occurs primarily in a first vibration mode; and / or (y) the exhaust flow channel may occupy a continuous space around the entire circumference of the vent housing.

[0130] In further examples of the above aspects: (a) the first side of the movable portion of the membrane faces radially inward and the second side of the movable portion of the membrane faces radially outward; (b) the first side of the movable portion of the membrane faces radially outward and the second side of the movable portion of the membrane faces radially inward; and / or (c) the membrane has a first end and a second end spaced apart along the longitudinal axis of the membrane, and the movable portion is located between the first end of the membrane and the second end of the membrane around the longitudinal axis.

[0131] 3.6 Exhaust flow passage including regions with smaller cross-sectional areas than adjacent regions

[0132] Another aspect of the present technology relates to a ventilation system for use with a patient interface, the ventilation system for providing a therapeutic gas flow pressurized above ambient pressure within a therapeutic pressure range to a patient for respiratory therapy. The therapeutic gas flow can be pressurized by a respiratory pressure therapy device and can be provided throughout the patient's respiratory cycle. The ventilation system can be configured to provide a ventilation flow to discharge exhaled gas from a patient from a pressurized volume, the ventilation system comprising: a ventilation housing comprising at least one exhaust orifice to allow exhaust to be discharged from the pressurized volume to the atmosphere; a membrane located within the ventilation housing, the membrane having a movable portion, the movable portion having a first side and a second side, wherein the movable portion of the membrane is spaced from a membrane-facing surface within the ventilation housing to form an exhaust flow channel on the second side of the membrane between the movable portion of the membrane and the membrane-facing surface, the exhaust flow channel allowing exhaust to flow from the pressurized volume through the exhaust flow channel via the at least one exhaust orifice to the atmosphere during use; wherein the exhaust flow channel comprises an area having a smaller cross-sectional area than an adjacent area of ​​the exhaust flow channel, and wherein the movable portion of the membrane is elastically deformable and is configured to move relative to the membrane-facing surface in response to a pressure differential between the first side of the membrane and the second side of the membrane to change the cross-sectional area of ​​the exhaust flow channel and regulate the ventilation flow over the entire therapeutic pressure range.

[0133] A patient interface comprises: a plenum chamber which at least partially forms a volume that can be pressurized to a therapeutic pressure of at least 6 cmH2O above ambient air pressure throughout the patient's breathing cycle in use, the plenum chamber including a plenum chamber inlet port, the plenum chamber inlet port being sized and structured to receive a therapeutic airflow for breathing by the patient from the volume; a seal-forming structure which is constructed and arranged to seal with an area of ​​the patient's face surrounding an entrance to the patient's airway, the seal-forming structure having holes therein so that during use the therapeutic airflow is delivered to at least the entrance to the patient's nostrils, the seal-forming structure being constructed and arranged to maintain the therapeutic pressure in the plenum chamber during the patient's breathing cycle in use; a positioning and stabilizing structure which is configured to maintain the seal-forming structure in a therapeutically effective position on the patient's head; and a ventilation structure which is configured to discharge a ventilation airflow to the atmosphere, the ventilation airflow being continuous throughout the patient's breathing cycle. The vent structure comprises: a vent housing comprising at least one exhaust orifice configured for exhausting gas to atmosphere, the at least one exhaust orifice being sized and shaped to maintain a therapeutic pressure in the plenum during use; a membrane positioned within the vent housing, the membrane having a first end and a second end spaced apart along a longitudinal axis of the membrane, the membrane having a movable portion positioned between the first end of the membrane and the second end of the membrane about the longitudinal axis, wherein the movable portion of the membrane comprises a first side and a second side and is radially spaced apart from a membrane-facing surface of an interior of the vent housing relative to the longitudinal axis of the membrane to form an exhaust flow channel between the movable portion of the membrane and the membrane-facing surface on the second side of the membrane, the exhaust flow channel being configured to allow exhaust gas from the pressurized volume to pass through the plenum during use. an exhaust flow channel flowing to the atmosphere via the at least one exhaust orifice; wherein the exhaust flow channel includes an area between the movable portion of the membrane and the surface facing the membrane, the area having a smaller cross-sectional area than an adjacent area of ​​the exhaust flow channel, and wherein the movable portion of the membrane is elastically deformable and is configured to move radially relative to the surface facing the membrane in response to a pressure differential between the first side of the membrane and the second side of the membrane to change the cross-sectional area of ​​the exhaust flow channel and regulate ventilation airflow throughout the therapeutic pressure range; and wherein the patient interface is configured to allow the patient to breathe from the ambient environment through their mouth in the absence of a flow of pressurized air through the plenum inlet port, or the patient interface is configured such that the patient's mouth is uncovered.

[0134] In examples of the above aspects, (a) the exhaust flow channel may include a restriction portion forming an area with a smaller cross-sectional area; (b) the surface facing the membrane may be closest to the movable portion of the membrane at the position of the restriction portion; (c) the surface facing the membrane may include a restrictor portion forming a restriction portion in the exhaust flow channel; (d) the surface facing the membrane may include a contoured surface forming the restrictor portion; (e) the restrictor portion may include ribs in the surface facing the membrane; (f) the restrictor portion may be centrally located between the first end of the membrane and the second end of the membrane; (g) the ventilation structure may include a damping chamber within the ventilation housing, the damping chamber being configured to damp vibrations of the movable portion of the membrane, wherein the damping chamber includes a first end adjacent to the first end of the membrane and a second end adjacent to the second end of the membrane, the restriction in the exhaust flow channel The ventilation housing may include an inlet for receiving an airflow from a respiratory pressure therapy device and an outlet for supplying the therapeutic airflow to the patient interface; (i) the ventilation housing may include a first housing member at a first end of the ventilation housing and a second housing member at a second end of the ventilation housing, the first housing member and the second housing member being configured to be connected together; (j) the first housing member may include the inlet and the inlet connecting portion configured to connect the ventilation structure fluid to a supply conduit; (k) the second housing member may include the outlet and the outlet connecting portion configured to connect the ventilation structure fluid to the patient interface; and / or (l) the exhaust flow channel may occupy a continuous space around the entire circumference in the ventilation housing.

[0135] 3.7 Ventilation structure with radially outward deformation membrane

[0136] Another aspect of the present technology relates to a ventilation system for use with a patient interface, the ventilation system being used to provide a therapeutic gas flow pressurized to above ambient pressure within a therapeutic pressure range to a patient for respiratory therapy. The therapeutic gas flow can be pressurized by a respiratory pressure therapy device and can be provided throughout the patient's breathing cycle. The ventilation system can be configured to provide a ventilation gas flow to discharge gas exhaled by the patient from a pressurized volume. The ventilation gas flow can be continuous throughout the patient's breathing cycle. The ventilation system can include: a ventilation housing comprising at least one exhaust orifice to allow exhaust gas to be discharged from the pressurized volume to the atmosphere; and a membrane within the ventilation housing, the membrane having a first end and a second end spaced apart along a longitudinal axis of the membrane, the membrane having a movable portion between the first end of the membrane and the second end of the membrane about the longitudinal axis. The movable portion of the membrane may be spaced radially inwardly from a membrane-facing surface within the ventilation housing relative to the longitudinal axis of the membrane to form an exhaust flow channel between the movable portion of the membrane and the membrane-facing surface, the exhaust flow channel allowing exhaust gas to flow from the pressurized volume through the exhaust flow channel to the atmosphere via the at least one exhaust orifice during use. The movable portion of the membrane is elastically deformable and is configured to move radially relative to the membrane-facing surface in response to a pressure differential between an inner side of the membrane and an outer side of the membrane to vary a cross-sectional area of ​​the exhaust flow channel and regulate ventilation airflow over the entire therapeutic pressure range.

[0137] According to another aspect of the present technology, a patient interface is provided, comprising: a plenum chamber that at least partially forms a volume that can be pressurized to a therapeutic pressure of at least 6 cmH2O above ambient air pressure throughout the patient's breathing cycle in use, the plenum chamber including a plenum chamber inlet port that is sized and structured to receive a therapeutic airflow for breathing by the patient from the pressurized volume; a seal-forming structure that is constructed and arranged to seal with an area of ​​the patient's face surrounding an entrance to the patient's airway, the seal-forming structure having holes therein so that the therapeutic airflow is delivered to at least the entrance to the patient's nostrils, the seal-forming structure being constructed and arranged to maintain the therapeutic pressure in the plenum chamber during the patient's breathing cycle in use; a positioning and stabilizing structure that is configured to maintain the seal-forming structure in a therapeutically effective position on the patient's head; and a ventilation structure that is configured to discharge a ventilation airflow to the atmosphere, the ventilation airflow being continuous throughout the patient's breathing cycle. The vent structure comprises: a vent housing including at least one exhaust orifice configured to exhaust gas to the atmosphere, the at least one exhaust orifice being sized and shaped to maintain a therapeutic pressure in the plenum during use; a membrane positioned within the vent housing, the membrane having a first end and a second end spaced apart along a longitudinal axis of the membrane, the membrane having a movable portion positioned between the first end of the membrane and the second end of the membrane about the longitudinal axis; wherein the movable portion of the membrane is radially inwardly spaced from a membrane-facing surface of an interior of the vent housing relative to the longitudinal axis of the membrane to form an exhaust flow channel between the movable portion of the membrane and the membrane-facing surface. , the exhaust flow channel is configured to allow exhaust gas to flow from the pressurized volume through the exhaust flow channel via the at least one exhaust orifice to the atmosphere during use; wherein the movable portion of the membrane is elastically deformable and is configured to move radially relative to the surface facing the membrane in response to a pressure differential between the inside of the membrane and the outside of the membrane to change the cross-sectional area of ​​the exhaust flow channel and regulate ventilation airflow throughout the therapeutic pressure range; and wherein the patient interface is configured to allow the patient to breathe from the ambient environment through their mouth in the absence of a flow of pressurized air through the inlet port of the inflation chamber, or the patient interface is configured so that the patient's mouth is uncovered.

[0138] In examples of the above aspects, (a) the movable portion of the membrane may be substantially cylindrical or frustoconical; (b) the vent housing may include a first end and a second end aligned along a longitudinal axis of the vent housing, the longitudinal axis of the membrane being aligned with the longitudinal axis of the vent housing; (c) the longitudinal axis of the membrane may be aligned substantially parallel to a direction of airflow through the vent housing from the first end of the vent housing to the second end of the vent housing; (d) the movable portion of the membrane may include one or more walls, the one or more walls being parallel to the vent housing; (e) the movable portion of the membrane may include a cylindrical wall having an axis aligned parallel to the direction of airflow through the vent housing from the first end of the vent housing to the second end of the vent housing; (f) the vent structure may include a membrane support member, the membrane being supported on the membrane support member; (g) the membrane may be molded to the membrane support member at the first end of the membrane; (h) the membrane support member may be configured to be connected to the vent housing; (i) the movable portion of the membrane may be formed of silicone rubber; (j) the ventilation housing may include a first housing member at a first end of the ventilation housing and a second housing member at a second end of the ventilation housing, the first housing member and the second housing member being configured to be connected together; (k) the first housing member may include an inlet connection portion configured to connect the ventilation structure fluid to a supply conduit; (l) the inlet connection portion may be provided at or near the first end of the first housing member; (m) the inlet connection portion may include a bayonet fitting configured to engage a corresponding fitting on the supply conduit; (n) the second housing member may include an outlet connection portion configured to connect the ventilation structure fluid to a patient interface; (o) the outlet connection portion may be configured to connect to the patient interface or to a tube connected to the patient interface; (p) the outlet connection portion may include an internally threaded portion configured to engage a correspondingly threaded portion of the patient interface or a tube of the patient interface; and / or (q) the exhaust flow channel may occupy a continuous space around the entire circumference in the ventilation housing.

[0139] In further examples of the above aspects, (a) the vent structure may include a damping structure configured to damp vibrations of the movable portion of the membrane; (b) the damping structure may include a damping chamber within the vent housing; (c) the vent housing may partially define the damping chamber; (d) one of the inner and outer sides of the membrane may face the membrane-facing surface, and the other of the inner and outer sides of the membrane may partially define the damping chamber; (e) the damping chamber may be in fluid communication with the pressurized volume in use; and (f) the vent structure may be configured such that movement of the movable portion of the membrane increases or decreases the damping chamber. (g) the vent housing and the damping chamber may be configured to damp vibrations of the movable portion of the membrane by limiting the exchange of gas between the damping chamber and the pressurized volume; (h) the vent structure may include at least one damping hole through which gas can flow from the pressurized volume into and out of the damping chamber, the damping hole preventing the exchange of gas between the damping chamber and the pressurized volume; (i) the vent structure may include a plurality of damping orifices through which gas can flow from the pressurized volume into and out of the damping chamber, the plurality of damping orifices together preventing the exchange of gas between the damping chamber and the pressurized volume; (j) the exhaust flow The movable passage may include an area having a smaller cross-sectional area than an adjacent area of ​​the exhaust flow passage; (k) the exhaust flow passage may include a restriction forming an area having a smaller cross-sectional area; (l) the membrane-facing surface may be proximal to the movable portion of the membrane at the location of the restriction; (m) the membrane-facing surface may include a restrictor portion forming a restriction in the exhaust flow passage; (n) the membrane-facing surface may include a contoured surface forming the restrictor portion; (o) the restrictor portion may include ribs in the membrane-facing surface; (p) the restrictor portion may include an area of ​​increased material thickness; (q) The restrictor portion may be centrally located between the first end of the membrane and the second end of the membrane; (r) the damping chamber may include a first end adjacent to the first end of the membrane and a second end adjacent to the second end of the membrane; (s) the restriction in the exhaust flow channel may be centrally aligned between the first end of the damping chamber and the second end of the damping chamber; (t) the ventilation housing may be configured such that vibration of the movable portion of the membrane occurs primarily in a first vibration mode; (u) the damping chamber may be further defined by one or more walls of the second housing member; and / or (v) the damping chamber may be further defined by one or more walls of the membrane support member.

[0140] In a further example of the above aspects, (a) the vent housing may be configured to limit movement of the movable portion of the membrane toward the surface facing the membrane; (b) the vent housing may contact an end of the membrane and prevent the end of the membrane from moving toward the surface facing the membrane; (c) the vent housing may include at least one protrusion, which is configured to contact the end of the membrane and limit movement of the end of the membrane toward the surface facing the membrane; (d) the at least one protrusion is arranged outside the exhaust flow channel; and / or (e) the vent housing may include multiple protrusions and may define multiple damping orifices between the multiple protrusions, through which gas can flow into and out of the damping chamber from the pressurized volume, and these damping orifices prevent gas exchange between the damping chamber and the pressurized volume to damp vibrations of the movable portion of the membrane.

[0141] In further examples of the above aspects, (a) the ventilation airflow may flow radially outward at or near the inlet of the exhaust flow passage; (b) the ventilation airflow may change direction from the radial direction to an axial direction aligned with the longitudinal axis of the ventilation structure when passing through the inlet of the exhaust flow passage; (c) the ventilation housing may include a circular surface at or near the inlet of the exhaust flow passage; (d) the circular surface may facilitate the change in direction of the ventilation airflow near the inlet of the exhaust flow passage; (e) the ventilation housing may include a plurality of exhaust apertures; (f) the exhaust apertures may be spaced around the circumference of the ventilation housing; (g) the ventilation housing may The invention provides a ventilation housing according to claim 1, wherein the ventilation housing comprises at least one diffuse exhaust aperture and at least one non-diffuse exhaust aperture; (h) the ventilation housing may comprise a plurality of diffuse exhaust apertures and a plurality of non-diffuse exhaust apertures; (i) the at least one diffuse exhaust aperture and the at least one non-diffuse exhaust aperture may be spaced apart along the longitudinal axis of the ventilation housing; (j) the diffuse exhaust aperture may be located at or near the first end of the ventilation housing; (k) the non-diffuse exhaust aperture may be centrally located between the first end of the ventilation housing and the second end of the ventilation housing; (l) the at least one diffuse exhaust aperture may open in a lateral direction; (m) the at least one non-diffuse exhaust aperture may be located at a position adjacent to the first end of the ventilation housing; (n) the vent structure may include a diffuser member configured to diffuse and / or audibly shield the exhaust gas; (o) the diffuser member may be positioned in series with the at least one diffuse exhaust orifice so as to require gas flowing through the at least one diffuse exhaust orifice to flow through the diffuser member; (p) the vent structure may provide a diffused exhaust flow path through which exhaust gas can be ventilated through the diffuser member and the at least one diffuse exhaust orifice; (q) the vent structure may provide an undiffused exhaust flow path through which exhaust gas can be ventilated through the vent structure. at least one undiffused exhaust orifice for ventilation; (r) the vent structure can be configured to permit exhaust gas to flow through the at least one undiffused exhaust orifice in the event that the exhaust gas is unable to flow through the at least one diffused exhaust orifice; (s) the vent structure can be shaped to require the exhaust gas flow to change direction to a greater extent to flow through the at least one undiffused exhaust orifice than to flow through the diffused exhaust orifice; and / or (t) the vent structure can be shaped to require the exhaust gas flow to change direction to flow through the undiffused exhaust orifice to a sufficient extent that a majority of the exhaust gas flow passes through the diffuser member and through the diffused exhaust orifice unless the diffuser member becomes clogged.

[0142] In a further example of the above aspects, (a) the ventilation structure may include an exhaust orifice member, the exhaust orifice member including the at least one exhaust orifice; (b) the exhaust orifice member may include multiple exhaust orifices; (c) the exhaust orifice member may be configured to be connected to the first shell member; (d) the exhaust orifice member may be formed in the shape of a ring; (e) the exhaust orifice member may include multiple exhaust orifices spaced around the circumference of the ring; (f) the at least one diffused exhaust orifice may be provided at or near the first end of the exhaust orifice member; (g) the at least one non-diffused exhaust orifice may be provided at or near the second end of the exhaust orifice member opposite to the first end of the exhaust orifice member; (h) the diffuser member may be retained in the ventilation structure by the exhaust orifice member; and / or (i) the diffuser member may be accommodated between the exhaust orifice member and the first shell member.

[0143] In further examples of the above aspects, (a) the movable portion of the membrane may be supported radially inwardly from the membrane-facing surface relative to the longitudinal axis of the membrane; (b) the movable portion of the membrane may be configured to move outwardly to restrict ventilation airflow; (c) the movable portion of the membrane may be configured to expand to move the membrane-facing surface outwardly; (d) the membrane-facing surface may be disposed on the inner surface of the first shell member; (e) the membrane-facing surface may be cylindrical or frustoconical; (f) the membrane support may include a baffle portion; (g) the baffle portion may be cylindrical; (h) the baffle portion may be concentric with the movable portion of the membrane; (i) the baffle portion may be disposed on the membrane (j) the baffle portion may have a first end connected to the movable portion of the membrane at the first end of the membrane and a second end disposed at or near the second end of the membrane; (k) the baffle portion may include an outwardly extending flange at the second end of the baffle portion; (l) the circular surface at or near the inlet of the exhaust flow channel may be a fillet disposed at the second end of the membrane support; (m) the circular surface may be disposed on the outwardly extending flange of the baffle portion of the membrane support; (n) the damping chamber may be partially defined by the baffle portion of the membrane support; (o) the damping chamber may be partially defined by the outwardly extending baffle portion of the membrane support (i) the first housing member may include a first housing member having a plurality of protrusions extending therefrom; (ii) the first housing member may include a plurality of protrusions extending therefrom; (iii) the first housing member may include a plurality of protrusions extending therefrom; (iv) the first housing member may include a plurality of protrusions extending therefrom; (v ... a cylindrical sleeve on the first shell member; (w) the first shell member may be substantially cylindrical and have a second shell member connecting portion at a second end of the first shell member and a diffuser support flange at a second end of the first shell member; (x) a diffuser may be retained in a diffuser passage between the diffuser support flange of the first shell member, the second shell member connecting portion of the first shell member, and the diffuser retaining portion of the second shell member; (y) the at least one exhaust aperture may be disposed in the diffuser retaining portion of the second shell member or may be formed by a gap between the diffuser retaining portion of the second shell member and the diffuser support flange of the first shell member;and / or (z) a plurality of exhaust apertures may be provided in the diffuser retaining portion of the second housing member and / or in a gap between the diffuser retaining portion of the second housing member and the diffuser support flange of the first housing member.;

[0144] Another aspect of one form of the present technology is a ventilation system configured to regulate a flow of pressurized breathable gas, the ventilation system comprising a movable membrane having an elongated shape about an axis of the membrane. The membrane may be generally cylindrical, frustoconical, etc.

[0145] Another aspect of one form of the present technology is a ventilation system configured to regulate a pressurized flow of breathable gas, the ventilation system comprising a movable membrane having a first end and a second end spaced apart along a longitudinal axis, the membrane having a movable portion about the longitudinal axis between the first end and the second end, the ventilation system comprising a housing configured to limit movement of the second end of the membrane toward a surface facing the membrane.

[0146] Another aspect of one form of the present technology is a ventilation system configured to regulate a pressurized flow of breathable gas, the ventilation system including a membrane having a movable portion, the ventilation system further comprising a damping structure configured to damp vibrations of the movable portion of the membrane.

[0147] Another aspect of one form of the present technology is a ventilation system configured to regulate a pressurized flow of breathable gas, the ventilation system comprising a membrane having a movable portion, the ventilation system comprising a ventilation housing configured to reduce vibration of the movable portion of the membrane at a vibration mode higher than a first vibration mode.

[0148] Another aspect of one form of the present technology is a ventilation system configured to regulate a pressurized flow of breathable gas, the ventilation system comprising a membrane having a movable portion, the movable portion having a first side and a second side, an exhaust flow channel disposed on the first side of the movable portion, and a entrapment air cavity disposed on the second side of the movable portion.

[0149] Another aspect of one form of the present technology is a ventilation system configured to regulate a pressurized flow of breathable gas, the ventilation system comprising a membrane having a movable portion and an exhaust flow channel including a region having a smaller cross-sectional area than adjacent regions of the exhaust flow channel.

[0150] Another aspect of one form of the present technology is a ventilation system configured to regulate a pressurized flow of breathable gas, the ventilation system comprising a membrane having a first end and a second end spaced apart along a longitudinal axis, and a movable portion about the longitudinal axis between the first end and the second end, the movable portion being a membrane-facing surface provided radially inward relative to the longitudinal axis, with an exhaust flow channel between the membrane-facing surfaces.

[0151] Another aspect of the present technology relates to a patient interface comprising: a seal-forming structure configured to seal to a patient's face, including at least around the patient's nostrils; an inflatable chamber connected to the seal-forming structure; a positioning and stabilizing structure for securing the patient interface to the patient during use; and a ventilation system according to any aspect and / or example of the above technology.

[0152] Of course, a part of these aspects may form a sub-aspect of the present technology. In addition, each aspect in the sub-aspect and / or aspect may be combined in various ways and also constitute other aspects or sub-aspects of the present technology.

[0153] Other features of the technology will become apparent from consideration of the information contained in the following detailed description, abstract, drawings, and claims. 4 Description of the accompanying drawings

[0154] The present technology is illustrated by way of example and not limitation in the accompanying figures and in which like reference numerals indicate similar elements, including:

[0155] 4.1 Treatment System

[0156] Figure 1A A system is shown that includes a patient 1000 wearing a patient interface 3000 in the form of nasal pillows and receiving a supply of air at positive pressure from an RPT device 4000. The air from the RPT device 4000 is humidified in a humidifier 5000 and delivered to the patient 1000 along an air circuit 4170. A bed partner 1100 is also shown. The patient sleeps in a supine position.

[0157] Figure 1B A system is shown that includes a patient 1000 wearing a patient interface 3000 in the form of a nasal mask receiving a supply of air at positive pressure from an RPT device 4000. The air from the RPT device is humidified in a humidifier 5000 and delivered to the patient 1000 along an air circuit 4170.

[0158] Figure 1C A system is shown that includes a patient 1000 wearing a patient interface 3000 in the form of a full face mask, receiving a supply of air under positive pressure from an RPT device 4000. The air from the RPT device is humidified in a humidifier 5000 and delivered along an air circuit 4170 to the patient 1000. The patient sleeps in a side-lying position.

[0159] 4.2 Respiratory system and facial anatomy

[0160] Figure 2A Shown is a schematic diagram of the human respiratory system including the nasal and oral cavities, larynx, vocal cords, esophagus, trachea, bronchi, lungs, alveolar sacs, heart, and diaphragm.

[0161] 4.3 Patient Interface

[0162] Figure 3A A patient interface in the form of a nasal mask is shown in accordance with one form of the present technology.

[0163] 4.4RPT device

[0164] Figure 4A One form of RPT device according to the present technology is shown.

[0165] Figure 4B Schematic diagram of the pneumatic path of an RPT device according to one form of the present technology. Upstream and downstream directions are indicated with reference to the blower and the patient interface. The blower is defined as upstream of the patient interface and the patient interface is defined as downstream of the blower, regardless of the actual flow direction at any given moment. Items within the pneumatic path between the blower and the patient interface are downstream of the blower and upstream of the patient interface.

[0166] 4.5 Humidifier

[0167] Figure 5A Shown is an isometric view of a humidifier according to one form of the present technology.

[0168] Figure 5B An isometric view of a humidifier according to one form of the present technology is shown, showing the humidifier reservoir 5110 removed from the humidifier reservoir base 5130. Figure 5C A schematic diagram of a humidifier according to one form of the present technology is shown.

[0169] 4.6 Respiratory Waveform

[0170] Figure 6A A typical breathing waveform of a model of a sleeping person is shown.

[0171] 4.7 Screening, diagnosis and monitoring systems

[0172] Figure 7A A patient undergoing a polysomnogram (PSG) is shown. The patient sleeps in a supine position.

[0173] Figure 7B A monitoring device for monitoring the condition of a patient is shown. The patient is sleeping in a supine sleeping position.

[0174] 4.8 Ventilation System

[0175] Figure 8 A graph illustrating the flow of ventilation airflow through a ventilation system 3400 according to an example of the present technology over a therapeutic pressure range is shown.

[0176] Figure 9A An exploded view illustration of a ventilation system 3400 is shown in accordance with one example of the present technology.

[0177] Figure 9B Shown Figure 9A is a side view illustration of a ventilation system 3400 shown in .

[0178] Figure 9C Shown Figure 9A A cross-sectional view of a ventilation system 3400 is shown in FIG.

[0179] Figure 9D Shown Figure 9A Another cross-sectional view of the ventilation system 3400 is shown in FIG.

[0180] Figure 9E Shown when connected to upstream and downstream components Figure 9A Another cross-sectional view of the ventilation system 3400 is shown in FIG.

[0181] Figure 9F Shown Figure 9A Another cross-sectional view of a portion of ventilation system 3400 is shown during therapy using a low therapy pressure.

[0182] Figure 9G Shown Figure 9A Another cross-sectional view illustration of a portion of ventilation system 3400 is shown during therapy using a high therapy pressure.

[0183] Figure 10A An exploded view illustration of a ventilation system 3400 according to another example of the present technology is shown.

[0184] Figure 10B Shown Figure 10A is a side view illustration of a ventilation system 3400 shown in .

[0185] Figure 10C Shown Figure 10A A cross-sectional view of a ventilation system 3400 is shown in FIG.

[0186] Figure 10D Shown Figure 10A Another cross-sectional view of the ventilation system 3400 is shown in FIG.

[0187] Figure 11A An exploded view illustration of a ventilation system 3400 according to another example of the present technology is shown.

[0188] Figure 11B Shown Figure 11A is a side view illustration of a ventilation system 3400 shown in .

[0189] Figure 11C Shown Figure 11A A cross-sectional view of a ventilation system 3400 is shown in FIG.

[0190] Figure 11D Shown Figure 11A Another cross-sectional view of the ventilation system 3400 is shown in FIG.

[0191] Figure 12A An exploded view illustration of a ventilation system 3400 according to another example of the present technology is shown.

[0192] Figure 12B Shown Figure 12A is a side view illustration of a ventilation system 3400 shown in .

[0193] Figure 12C Shown Figure 12A A cross-sectional view of a ventilation system 3400 is shown in FIG.

[0194] Figure 12D Shown Figure 12A Another cross-sectional view of the ventilation system 3400 is shown in FIG.

[0195] Figure 13 Depicted are schematic diagrams showing options for using the ventilation system of the present technology with various patient interfaces. 5. Specific Implementation Methods

[0196] Before describing the present technology in further detail, it should be understood that the present technology is not limited to the specific examples described herein, which may vary. It should also be understood that the terminology used in this disclosure is for the purpose of describing the specific examples described herein only and is not intended to be limiting.

[0197] The following description is provided in relation to various examples that may share one or more common features and / or characteristics. It should be understood that one or more features of any one example may be combined with one or more features of another example or other examples. In addition, in any of the examples, any single feature or combination of features may constitute another example.

[0198] 5.1 Treatment

[0199] In one form, the present technology comprises a method for treating a breathing disorder comprising applying positive pressure to an airway entrance of a patient 1000 .

[0200] In some examples of the present technology, a supply of air at positive pressure is provided to the patient's nasal passages via one or both nostrils.

[0201] In some examples of the present technology, mouth breathing is limited, restricted, or prevented.

[0202] 5.2 Treatment System

[0203] In one form, the present technology includes an apparatus or device for treating a respiratory disorder. The apparatus or device may include an RPT device 4000 for supplying pressurized air to a patient 1000 via an air circuit 4170 to a patient interface 3000 .

[0204] 5.3 Patient Interface

[0205] A non-invasive patient interface 3000 according to one aspect of the present technology includes the following functional aspects: a seal-forming structure 3100, a plenum chamber 3200, a positioning and stabilizing structure 3300, a ventilation system 3400, a connection port 3600 for connecting to a form of air circuit 4170, and a forehead support 3700. In some forms, the functional aspects may be provided by one or more physical components. In some forms, one physical component may provide one or more functional aspects. In use, the seal-forming structure 3100 is arranged to surround the entrance to the patient's airway to facilitate the supply of positive pressure air to the airway.

[0206] If a patient interface cannot comfortably deliver a minimum level of positive pressure to the airway, the patient interface may not be suitable for respiratory pressure therapy.

[0207] A patient interface 3000 in accordance with one form of the present technology is constructed and arranged to supply air at a positive pressure of at least 6 cmH20 relative to ambient.

[0208] A patient interface 3000 in accordance with one form of the present technology is constructed and arranged to supply air at a positive pressure of at least 10 cmH20 relative to ambient.

[0209] A patient interface 3000 in accordance with one form of the present technology is constructed and arranged to supply air at a positive pressure of at least 20 cmH20 relative to ambient.

[0210] 5.3.1 Sealing structure

[0211] In one form of the present technology, the seal-forming structure 3100 provides a target seal-forming area and may additionally provide a cushioning function. The target seal-forming area is the area on the seal-forming structure 3100 where sealing is likely to occur. The area where sealing actually occurs—the actual sealing surface—can vary from day to day and from patient to patient within a given course of treatment, depending on a number of factors, including, for example, where the patient interface is placed on the face, the tension in the positioning and stabilizing structure, and the shape of the patient's face.

[0212] In one form, the target seal-forming area is located on an outer surface of the seal-forming structure 3100 .

[0213] In some forms of the present technology, the seal-forming structure 3100 is constructed from a biocompatible material such as silicone rubber.

[0214] A seal-forming structure 3100 in accordance with the present technology may be constructed from a soft, flexible, elastic material, such as silicon.

[0215] In certain forms of the present technology, a system is provided that includes more than one seal-forming structure 3100, each seal-forming structure 3100 configured to correspond to a different range of sizes and / or shapes. For example, the system may include one form of seal-forming structure 3100 that is suitable for large heads but not small heads, and another form of seal-forming structure 3100 that is suitable for small heads but not large heads.

[0216] 5.3.1.1 Sealing mechanism

[0217] In one form, the seal-forming structure includes a sealing flange that utilizes a pressure-assisted sealing mechanism. In use, the sealing flange can readily respond to the positive system pressure acting on its bottom surface within the plenum 3200, thereby forming a tight sealing engagement with the face. The pressure-assisted mechanism can act in conjunction with the elastic tension in the positioning and stabilizing structure.

[0218] In certain forms of the present technology, the seal-forming structure may include one or more of a pressure-assisted sealing flange, a compression sealing portion, a gasket sealing portion, a tensioning portion, and a portion having a tacky or adhesive surface.

[0219] 5.3.1.2 Mid-nose or nasal bridge area

[0220] In one form, the non-invasive patient interface 3000 includes a seal-forming structure that, in use, forms a seal over a mid-nasal region or a nasal bridge region of the patient's face.

[0221] In one form, the seal-forming structure includes a saddle-shaped region configured to form a seal when used on a mid-nasal region or a nasal bridge region of a patient's face.

[0222] 5.3.1.3 Upper lip area

[0223] In one form, the non-invasive patient interface 3000 includes a seal-forming structure that forms a seal on the upper lip region (ie, supra-lip) of the patient's face when in use.

[0224] In one form, the seal-forming structure comprises a saddle-shaped region configured to form a seal on an upper lip region of a patient's face in use.

[0225] 5.3.1.4 Chin area

[0226] In one form, the non-invasive patient interface 3000 includes a seal-forming structure that, in use, forms a seal over the chin region of the patient's face.

[0227] In one form, the seal-forming structure includes a saddle-shaped region configured to form a seal when used on a chin region of a patient's face.

[0228] 5.3.1.5 Forehead area

[0229] In one form, the seal-forming structure forms a seal on the forehead area of ​​the patient's face during use.In this form, the inflatable chamber can cover the eyes during use.

[0230] 5.3.1.6 Nasal pillows

[0231] In one form, the seal-forming structure of the non-invasive patient interface 3000 comprises a pair of nasal puffs or pillows, each constructed and arranged to form a seal with a corresponding nostril of the patient's nose.

[0232] A nasal pillow according to one aspect of the present technology includes: a frustoconical body, at least a portion of which forms a seal against the bottom surface of a patient's nose; a stem; and a flexible region on the bottom surface of the frustoconical body and connecting the frustoconical body to the stem. Furthermore, the structure to which the nasal pillows of the present technology are connected includes a flexible region adjacent to the bottom of the stem. The flexible regions can cooperate to facilitate a universal joint structure that can adapt to relative movement of both the displacement and angle between the frustoconical body and the structure to which the nasal pillows are connected. For example, the position of the frustoconical body can be moved axially toward the structure to which the stem is connected.

[0233] 5.3.2 Inflatable chamber

[0234] In the area where the seal is formed during use, the plenum 3200 has a perimeter that is shaped to complement the surface contours of an average person's face. In use, the boundary edge of the plenum 3200 is positioned in close proximity to the adjacent surface of the face. Actual contact with the face is provided by the seal-forming structure 3100. The seal-forming structure 3100 may extend along the entire perimeter of the plenum 3200 during use. In some embodiments, the plenum 3200 and the seal-forming structure 3100 are formed from a single homogeneous piece of material.

[0235] 5.3.3 Positioning and stabilizing the structure

[0236] The seal-forming structure 3100 of a patient interface 3000 of the present technology may be maintained in a sealed position during use by a positioning and stabilizing structure 3300 .

[0237] In one form, the positioning and stabilising structure 3300 provides a retaining force that is at least sufficient to overcome the positive pressure in the plenum 3200 to lift off the face.

[0238] In one form, the positioning and stabilising structure 3300 provides a retaining force to overcome the effects of gravity on the patient interface 3000 .

[0239] In one form, the positioning and stabilising structure 3300 provides a retaining force as a safety margin to overcome the potential effects of damaging forces on the patient interface 3000, such as from tube drag or accidental interference with the patient interface.

[0240] In one form of the present technology, a positioning and stabilizing structure 3300 is provided that is configured in a manner consistent with being worn by a patient while sleeping. In one example, the positioning and stabilizing structure 3300 has a low profile or cross-sectional thickness to reduce the perceived or actual bulk of the device. In one example, the positioning and stabilizing structure 3300 includes at least one strap having a rectangular cross-section. In one example, the positioning and stabilizing structure 3300 includes at least one flat strap.

[0241] In one form of the present technology, a positioning and stabilizing structure 3300 is provided that is configured to be not too large and bulky to prevent a patient from lying in a supine sleeping position with the back region of the patient's head on a pillow.

[0242] In one form of the present technology, a positioning and stabilizing structure 3300 is provided that is configured so as not to be too large and bulky to prevent a patient from assuming a side sleeping position with the side region of the patient's head resting on a pillow.

[0243] In certain forms of the present technology, a system is provided that includes more than one positioning and stabilizing structure 3300, each positioning and stabilizing structure configured to provide a retention force corresponding to a different range of sizes and / or shapes. For example, the system may include one form of positioning and stabilizing structure 3300 that is suitable for large heads but not for small heads, while another form of positioning and stabilizing structure is suitable for small heads but not for large heads.

[0244] 5.3.4 Ventilation system

[0245] In one form, patient interface 3000 includes a ventilation system 3400 constructed and arranged to allow washout of exhaled gases, such as carbon dioxide. Patient interface 3000 can be configured to provide respiratory therapy to a patient at a therapeutic flow of gas at a pressure above ambient pressure within a therapeutic pressure range via respiratory pressure therapy device 4000. Ventilation system 3400 may alternatively be identified as a ventilation structure, a ventilation assembly, and / or a vent.

[0246] In certain embodiments, the ventilation system 3400 is configured to allow continuous ventilation flow from the interior of the plenum 3200 to the ambient environment while the pressure within the plenum is positive relative to the ambient environment. The ventilation system 3400 is configured so that the ventilation flow has a magnitude sufficient to avoid or prevent the patient from rebreathing significant amounts of exhaled CO2 while maintaining a therapeutic pressure within the plenum during use. The ventilation flow from the ventilation system 3400 can be continuous throughout the patient's respiratory cycle.

[0247] The vent system / vent structure 3400 can be configured (eg, sized, shaped, and / or arranged) to maintain a therapeutic pressure in the plenum during use.

[0248] One form of a vent system 3400 in accordance with the present technology includes a plurality of apertures, for example, from about 20 to about 80 apertures, or from about 40 to about 60 apertures, or from about 45 to about 55 apertures.

[0249] The ventilation system 3400 can be located in the plenum 3200. Alternatively, the ventilation system 3400 is located in a decoupling structure (e.g., a rotating one). In one example, Figure 13 As shown, ventilation system 3400 is positioned within air circuit 4170. Ventilation system 3400 can fluidly connect a first portion of air circuit 4170 to a second portion of air circuit 4170. For example, ventilation system 3400 can fluidly connect a first portion of air circuit 4170 connected to RPT device 4000 to a second portion of air circuit 4170 (e.g., ventilation connector tube 4180), which is connected to patient interface 3000 and configured to connect with ventilation system 3400. In another example, ventilation system 3400 fluidly connects patient interface 3000 to air circuit 4170. In some examples, ventilation system 3400 can connect one end of air circuit 4170 to a decoupling structure 3500, such as a swivel elbow.

[0250] like Figures 9A-12DAs shown, a vent system 3400 according to an example of the present technology may include a vent housing 3402 and a membrane 3450. The membrane 3450 may have a non-planar shape, for example, the membrane 3450 may have a tubular shape, such as a cylindrical shape. The membrane 3450 may have a frustoconical shape, for example. In some examples, the membrane 3450 may include one or more walls that curve from one end to the other. In some examples, the membrane 3450 may have a spherical cross-section shape.

[0251] In some embodiments, the membrane 3450 includes axisymmetry, e.g., the membrane 3450 can include an axis about which the membrane 3450 is substantially symmetrical. For example, the membrane 3450 can include a longitudinal axis and the shape of the membrane 3450 can include axisymmetry about the longitudinal axis. The axisymmetry of the membrane 3450 and the ventilation housing 3402 also facilitates use of the ventilation system 3400 as a connector between portions of the air circuit 4170 or between the air circuit 4170 and the patient interface 3000. Many air circuit connector components are tubular or otherwise circular, thereby providing a central path through which therapeutic airflow can pass. The axisymmetry of the ventilation system 3400 can facilitate connection between portions of the air circuit while maintaining a similar form to the air circuit 4170, e.g., a slender form that may not be perceived as excessively wide compared to the air circuit 4170. The ventilation system can provide a central passage for therapeutic gas flow through the ventilation system 3400, while other features of the ventilation system 3400, such as exhaust flow paths and exhaust orifices, can be provided symmetrically about an axis of the ventilation system 3400 other than the axis. The exhaust flow channel can also be axisymmetric and can occupy a continuous space around the entire circumference of the ventilation housing.

[0252] The membrane 3450 may be configured to deform or deflect to change the cross-sectional area of ​​the exhaust flow path through which the ventilation air flow flows from the plenum 3200 to the atmosphere.

[0253] By dynamically adjusting the cross-sectional area of ​​the exhaust flow passage, the ventilation system 3400 can provide a substantially constant ventilation flow over a typical therapeutic pressure range. By constructing the ventilation system 3400 to maintain a constant ventilation flow over a large portion of the typical therapeutic pressure range, the need for the RPT device 4000 is reduced compared to conventional ventilation systems to provide sufficient air flow to maintain the desired therapeutic pressure within the plenum 3200 regardless of losses (e.g., due to ventilation). When the need for the RPT device 4000 is reduced, the cost of manufacturing such a device can be reduced because a less complex and lower power RPT device 4000 is required to provide the same level of therapy. Several exemplary configurations and a more detailed functional description of the ventilation system 3400 are as follows.

[0254] 5.3.4.1 Ventilation shell

[0255] Figures 9A to 9F , 10A-10D, 11A-11D, and 12A-12D depict examples of different ventilation system 3400 configurations. In these examples, the ventilation system 3400 includes a ventilation housing 3402. The ventilation housing 3402 can have a first end 3404 and a second end 3405. In these examples, the first end 3404 of the ventilation housing 3402 and the second end 3405 of the ventilation housing 3402 are aligned along a longitudinal axis 3406. The interior of the ventilation housing 3402 is a pressurized volume 6000. In some examples of the present technology, the pressurized volume 6000 can be part of the plenum 3200. In other examples, the pressurized volume 6000 can be located in a different location where exhaust gas flow may be desired, such as in the air circuit 4170. The pressurized volume 6000 can be located between a first portion of the air circuit 4170 and a second portion of the air circuit 4170 (e.g., the ventilation connector tube 4180).

[0256] The ventilation housing 3402 can be configured to receive airflow from the RPT device 4000 from a first end 3404 of the ventilation housing 3402 and supply a therapeutic airflow to the patient interface 3000 from a second end 3405 of the ventilation housing 3402. For example, the ventilation housing 3402 can include an inlet 3407 for receiving airflow and an outlet 3408 for supplying a therapeutic airflow. The ventilation housing 3402 includes at least one exhaust aperture to allow exhaust gas to be discharged from the pressurized volume 6000 to the atmosphere (indicated by numeral 6100). The ventilation airflow can flow from the pressurized volume 6000 to the atmosphere 6100 via at least one exhaust flow channel 6002.

[0257] The vent housing 3402 can be configured (e.g., sized, shaped, and / or arranged) to maintain a therapeutic pressure in the plenum chamber 3200 during use.

[0258] The ventilation housing 3402 can include a plurality of diffused exhaust orifices 3471. In other examples, the ventilation housing 3402 can include one diffused exhaust orifice 3471, or any number, including zero. In these examples, the ventilation housing 3402 can also include one or more non-diffused exhaust orifices 3472, which will be discussed in more detail below. In some examples, the ventilation system 3400 can be configured to vent exhaust to an area having a pressure lower than the pressurized volume 6000, but not to the atmosphere (or not directly to the atmosphere), such as the expiratory limb of the patient circuit 4170.

[0259] The at least one vent orifice 3471 (eg, a single vent orifice 3471 or a plurality thereof, as the case may be) may be sized and shaped to maintain a therapeutic pressure within the plenum chamber 3200 during use.

[0260] As will be described, the vent system includes a membrane-facing surface 3424 inside the vent housing 3402. The membrane-facing surface 3424 may be a surface of the vent housing 3402.

[0261] The vent housing 3402 can include a first housing member 3430 at a first end 3404 of the vent housing 3402 and a second housing member 3440 at a second end 3405 of the vent housing 3402. In these examples, the first housing member 3430 and the second housing member 3440 are configured to be connected together. The first housing member 3430 and the second housing member 3440 can be configured to be connected to each other indirectly or directly. In some examples of the present technology, the first housing member 3430 and the second housing member 3440 can be separated from each other, for example, by a threaded connection, a friction fit connection, a snap fit connection. In other examples, the first housing member 3430 and the second housing member 3440 can be permanently connected together, for example, by being integrally formed as one part, welding, a permanent snap fit, or using an adhesive.

[0262] Figure 9E A ventilation system 3400 is shown connected to components of an air circuit 4170 according to one example. The ventilation system 3400 is connected between the air circuit 4170 and the ventilation connector tube 4180. The ventilation housing 3402 is connected to the air circuit connector 4171 of the air circuit 4170 at the upstream end and to the tube connector 4182 at the downstream end. The ventilation system 3400 receives airflow from a respiratory pressure therapy (RPT) device, indicated by 6201, and delivers a therapeutic airflow, indicated by 6202, to a downstream patient interface. The ventilation system 3400 also allows ventilation airflow, indicated by 6203, to be exhausted to the atmosphere 6100. In this example, the ventilation airflow 6203 is exhausted as a diffused ventilation airflow, indicated by 6204, and an undiffused ventilation airflow, indicated by 6206.

[0263] 5.3.4.1.1 First shell component

[0264] In these examples, the first housing member 3430 includes an inlet 3407 leading to the ventilation housing 3402. The first housing member 3430 can include an inlet connection portion 3416 configured to fluidly connect the ventilation system 3400 to a supply conduit (e.g., the air circuit 4170). The inlet connection portion 3416 can be positioned toward a first end 3431 of the first housing member 3430 (e.g., the upstream end of the first housing member), such as at or near the first end 3431 of the first housing member 3430. The inlet connection portion 3416 can include a bayonet fitting 3418 configured to engage a corresponding fitting of the air circuit 4170. In other examples, the inlet connection portion 3416 can be configured to fluidly connect to the air circuit 4170 by another means, such as by a snap-fit ​​connection or a friction fit. Figure 9E The ventilation system 3400 is shown in one example connected to an air circuit 4170 via an air circuit connector 4171 that engages the inlet connection.

[0265] The first housing member 3430 may include a shaft 3434 that is configured to extend into the interior of the ventilation system 3400, such as Figure 9C and 10C 34. In other examples of the present technology, the first housing member 3430 of the vent system 3400 does not include the shaft 3434. The shaft 3434 projects from the first end 3404 of the exhaust orifice housing 3402 toward the second end 3405 of the exhaust housing 3402. The shaft 3434 can be centrally located within the vent housing 3402. In these examples, the shaft 3434 extends into the pressurized volume 6000. The shaft 3434 can terminate at the second end 3432 of the first housing member 3430 (e.g., the downstream end of the first housing member) within the pressurized volume. The shaft 3434 is hollow with an opening at each end to receive the gas flow from the RPT device 4000 and supply it to the pressurized volume 6000.

[0266] In these examples, the axis 3434 is aligned with the longitudinal axis 3406 of the ventilation housing 3402. In other examples, the ventilation system 3400 can include an axis 3434 that is not centered and / or extends at an angle relative to the axis of the first housing member 3430 and / or the second housing member 3440. For example, the ventilation system 3400 incorporated into the swivel elbow of the patient interface 3000 can include multiple portions having axes that are not aligned to form the elbow shape.

[0267] The inlet connection portion 3416 of the first housing member 3430 is disposed on a shaft 3434. The shaft 3434 can include a substantially cylindrical outer surface at the first end 3431 of the first housing member 3430. In these examples, a bayonet fitting 3418 extends radially outward from the shaft 3434.

[0268] The membrane-facing surface 3424 can be disposed on the first housing member 3430. More specifically, the membrane-facing surface 3242 can be disposed on an outer surface of the first housing member 3430 of the vent housing 3402, which outer surface is located within the vent housing 3402. Figures 9A to 9G 10A to 10D, the membrane-facing surface 3424 is provided on the shaft 3434. In these examples, the membrane-facing surface 3424 is disposed on an outer side of the shaft 3434 toward the second end 3432 of the first housing member 3430, for example, at or near the second end 3432 of the first housing member 3430.

[0269] The membrane-facing surface 3424 may include a restrictor portion 3425 that forms an area having a smaller cross-sectional area than adjacent areas in the exhaust flow channel 6002. The restrictor portion 3425 may form a restriction in the exhaust flow channel 6002. The importance of a smaller cross-sectional area and / or restriction in the exhaust flow channel 6002 will be described below. The restrictor portion 3425 may be provided on an exterior portion of the shaft 3434 that faces the second end 3432 of the first housing member 3430, for example, at or near the second end 3432 of the first housing member 3430.

[0270] Examples of the present technology include various options for the restrictor portion. The membrane-facing surface 3424 may include a contoured surface forming a restrictor portion 3425, such as Figures 9C-9G As shown. Alternatively or additionally, the restrictor portion 3425 can include ribs in the membrane-facing surface. The ribs forming the restrictor portion 3425 can be disposed around the circumference of the shaft 3434. Alternatively or additionally, the restrictor portion 3425 can include an area of ​​increased material thickness of the first housing member 3430. In other examples of the present technology, the restrictor portion 3425 can be disposed on an inwardly facing surface of the vent housing 3402, such as where the membrane 3450 is located inwardly of the membrane-facing surface 3424.

[0271] First housing member 3430 may include a rounded surface 3433 facing second end 3432 of first housing member 3430, for example, at or near second end 3432 of first housing member 3430. Rounded surface 3433 may be formed by a rounded edge at the periphery of second end 3432 of first housing member 3430. This rounded surface 3433 may provide lower impedance to ventilation airflow entering exhaust flow channel 6002. This lower impedance to ventilation airflow entering exhaust flow channel 6002 may improve the efficiency of ventilation system 3400. Additionally, rounded surface 3433 prior to the inlet of exhaust flow channel 6002 may help prevent gas circulation areas within exhaust flow channel 6002 near the end of the shaft, which may form if sharp corners are present at the outer edge of shaft 3434. A smooth inlet of exhaust flow channel 6002 may also be achieved by non-circular geometry near the inlet, such as one or more chamfers, such as beveled edges, at the outer circumference of the end of shaft 3434.

[0272] The first housing member 3430 may include an outwardly projecting flange 3435. The flange 3435 may be positioned toward the first end 3431 of the first housing member 3430, for example, at or near the first end 3431 of the first housing member 3430. The flange 3435 may be located near the first end 3431 of the first housing member 3430, approximately midway between a center point along the axis 3434 and the first end 3431 of the first housing member 3430. The flange 3435 may extend outward from the axis 3434. The flange 3435 may be configured to connect to the exhaust aperture member 3470 of the vent system 3400. The side of the flange 3435 that faces the second end of the vent housing 3402 may be configured to connect to the exhaust aperture member 3470.

[0273] The flange 3435 may include a flange protrusion 3436 extending from the flange 3435 (in one example, Figure 9B ). In this example, the flange protrusion 3436 is configured to be connected to the exhaust orifice member 3470. The flange protrusion 3436 can protrude in a direction perpendicular to the flange 3435. In this example, the flange protrusion 3436 extends toward the exhaust orifice member 3470. The first housing member 3430 can include any number of flange protrusions 3436, such as one, two, three or more. The flange protrusion 3436 can form a removable connection with the exhaust orifice member 3470, such as a snap fit or friction fit connection. Alternatively, the flange protrusion 3436 can be permanently connected to the exhaust orifice member 3470, such as by being integrally formed with the exhaust orifice member 3470 or by bonding, welding or a permanent snap fit connection.

[0274] The membrane-facing surface 3424 may alternatively be provided on the inner surface of the first housing member 3430, such as Figures 11A to 11D 12A to 12D. The membrane-facing surface 3424 can have any suitable shape and structure. For example, the membrane-facing surface 3424 may be Figures 11A to 11D In the example, it is frustoconical and Figures 12A to 12D The middle is cylindrical.

[0275] 5.3.4.1.2 Second shell component

[0276] The second housing member 3440 may include a first end 3441 (eg, a second housing member upstream end) and a second end 3442 (eg, a second housing member downstream end) opposite the first end 3441 .

[0277] In these examples, the second housing member 3440 includes an outlet 3408 for supplying a therapeutic gas flow. The second housing member 3440 may include an outlet connection portion 3420 configured to fluidically connect the ventilation system 3400 to the patient interface 3000. The outlet connection portion 3420 may be configured to connect directly or indirectly to the patient interface 3000. In some examples, the outlet connection portion 3420 may be connected to a swivel elbow of the patient interface 3000 or to a portion of the air circuit 4170 connected between the ventilation system 3400 and the patient interface 3000, such as an air supply tube. In other examples, the outlet connection portion 3420 may be configured to connect to the patient interface 3000 or the ventilation connector tube 4180 or to a portion of the patient interface 3000 (e.g., Figure 13 ). The vent connector tube 4180 may be referred to as a "stub tube." Figure 9E The vent system 3400 in one example is shown connected to a vent connector tube 4180 via a tube connector 4182 engaged with an outlet connection portion 3420 .

[0278] The outlet connection portion 3420 may be configured to form a snap fit to engage a corresponding portion of the patient interface 3000, the tube connector 4182, or the ventilation connector tube 4180. Figures 9A to 9G 10A to 10D, the outlet connection portion 3420 includes a recess 3422 that is configured to receive a corresponding feature (not shown) provided on the patient interface 3000, the nipple 4180, the swivel elbow, or other adapter used to connect the outlet connection portion 3420 to the patient interface 3000. The corresponding feature can be, for example, a rib configured to snap fit into the recess 3422.

[0279] As will be described in greater detail below, the second housing member 3440 can include a plurality of protrusions 3444 to limit movement of the membrane 3450. The second housing member 3440 can include an inwardly extending membrane stop flange 3446 on which the protrusions 3444 are disposed.

[0280] 5.3.4.2 Membrane

[0281] The membrane 3450 can have a first end 3451 and a second end 3452 (e.g., a first membrane end 3451 and a second membrane end 3452). The first end 3451 of the membrane 3450 and the second end 3452 of the membrane 3450 can be spaced apart along a longitudinal axis 3454, such as in an example where the membrane 3450 is cylindrical, or has another axially symmetrical shape. The longitudinal axis 3454 of the membrane 3450 can be aligned with the longitudinal axis 3406 of the vent housing 3402.

[0282] 5.3.4.2.1 Removable part of the membrane

[0283] The membrane 3450 also includes a movable portion 3456, such as Figures 9A to 12D As shown. The movable portion 3456 of the membrane 3450 can be located between the first end 3451 of the membrane 3450 and the second end 3452 of the membrane 3450. In these examples, the first end 3451 of the membrane 3450 and the second end 3452 of the membrane 3450 are spaced apart along the longitudinal axis of the membrane 3450. The movable portion 3456 of the membrane 3450 can surround the longitudinal axis of the membrane 3450 between the first end 3451 of the membrane 3450 and the second end 3452 of the membrane 3450. The movable portion 3456 can be approximately centered between the first end 3451 of the membrane 3450 and the second end 3452 of the membrane 3450. The movable portion 3456 can be circumferentially arranged around the longitudinal axis of the membrane 3450. The membrane 3450 in these examples has an elongated shape, such as a tube or a tapered portion. In other examples, the movable portion 3456 may have a cross-sectional shape about the longitudinal axis of the membrane 3450 that is not completely circular, for example having lobes or in the form of a triangle with rounded sides.

[0284] The movable portion 3456 is radially spaced from the membrane-facing surface 3424 of the interior of the vent housing 3402 relative to the longitudinal axis of the membrane 3450. An exhaust flow channel 6002 is formed between the membrane-facing surface 3424 and the movable portion 3456 of the membrane 3450. The exhaust flow can flow from the pressurized volume 6000 through the exhaust flow channel 6002 during use. In this example, gas can flow to the atmosphere 6100 via the diffused exhaust orifice 3471 or the undiffused exhaust orifice 3472. Figures 9A-9EThe exhaust flow channel 6002 of the illustrated vent system 3400 may occupy a continuous space around the entire circumference in the vent housing 3402. The circumference may be around the longitudinal axis of the membrane 3450. In other examples of the present technology, there may be multiple discrete exhaust flow channels 6002.

[0285] 5.3.4.2.2 Operation of movable parts

[0286] The movable portion 3456 of the membrane 3450 is configured to move relative to the membrane-facing surface 3424. The movable portion 3456 of the membrane 3450 can be elastically deformable to facilitate movement. The movable portion 3456 of the membrane 3450 is movable in the sense that one or more regions or movable portions 3456 move. Translational movement of the movable portion 3456 as a whole is not required for the movable portion 3456 to be "movable". Figures 9A to 12D In some examples, the movable portion 3456 is movable because the material forming the movable portion 3456 is capable of moving by deformation (e.g., contraction or expansion). In other examples of the present technology, the movable portion 3456 may not deform and may instead translate, rotate, or move in other ways. In some examples, the movable portion 3456 of the membrane 3450 is configured to move radially relative to the membrane-facing surface 3424. In some examples, the movable portion 3456 of the membrane 3450 is configured to move radially inward. In other examples, the movable portion 3456 of the membrane 3450 is configured to move radially outward.

[0287] The movable portion 3456 of the membrane 3450 is configured to move relative to the membrane-facing surface 3424 to vary the cross-sectional area of ​​the exhaust flow channel 6002. The membrane 3450 is configured for regulating ventilation flow throughout a therapeutic pressure range.

[0288] The movable portion 3456 of the membrane 3450 can be configured to move in response to a pressure differential between the inside of the membrane 3450 and the outside of the membrane 3450. In these examples, the movable portion 3456 of the membrane 3450 is configured to move relative to the membrane-facing surface 3424 in response to a change in pressure in the pressurized volume 6000 relative to the atmosphere. The membrane 3450 can be exposed to a force generated by the pressure of the pressurized volume 6000 on one side (e.g., the outside) of the movable portion 3456 and to a lower force generated by the pressure of the gas in the exhaust flow channel 6002 on the other side (e.g., the inside) of the movable portion 3456. The difference in force on either side of the movable portion 3456 of the membrane 3450 can cause the movable portion 3456 to move. In particular, the exhaust flow in the exhaust flow channel 6002 can have a higher velocity and lower pressure than the gas in the pressurized volume 6000, in which case there will be a net force on the movable portion 3456 of the membrane 3450 in the direction of the exhaust flow channel 6002, thereby pushing the movable portion 3456 toward the surface facing the membrane.

[0289] The lower pressure in exhaust flow channel 6002 compared to pressurized volume 6000 can be caused, at least in part, by effects due to Bernoulli's principle. The higher velocity of the gas in exhaust flow channel 6002 compared to pressurized volume 6000 results in a lower pressure being exerted on movable portion 3456 of membrane 3450 on one side of exhaust flow channel 6002.

[0290] On the higher pressure side of the movable portion 3456 of the membrane 3450 (e.g., at Figures 9C-9G , 10C and 10D, or in the outside Figure 11C 、 11D , 12C and 12D), the ventilation system 3400 may include Figure 11C 、 11D , 12C, and 12D . In these examples, the entrapment air cavity 6040 is located on a first side of the movable portion 3456 of the membrane 3450, and the exhaust flow channel 6002 is located on a second side of the movable portion 3456 of the membrane 3450. The entrapment air cavity 6040 holds stationary or slowly moving air (or other breathable gas) compared to the air flowing through the exhaust flow channel 6002, which can increase the effect of Bernoulli's principle. Additionally, the trapped air in the entrapment air cavity may be less susceptible to turbulent movement of air, thereby reducing the chance of inducing vibrations in the movable portion 3456 of the membrane 3450. The entrapment air cavity may also facilitate damping vibrations in the movable portion 3456 of the membrane 3450.

[0291] At relatively high therapeutic pressures (e.g., 18 cmH2O), the pressure differential between the pressurized volume 6000 and the atmosphere 6100 (e.g., ambient pressure) will be relatively high. Without any movement of the movable portion 3456 of the membrane 3450 relative to the membrane-facing surface 3424, the flow rate of the ventilation airflow through the exhaust flow channel 6002 will also be relatively high. However, the relatively high exhaust flow rate results in a lower pressure acting on the movable portion 3456 of the membrane 3450 on one side of the exhaust flow channel 6002 relative to the other side. As a result, the movable portion 3456 of the membrane 3450 is pushed into the exhaust flow channel 6002 toward the membrane-facing surface 3424. When this occurs, the spacing between the membrane 3450 and the membrane-facing surface 3424 decreases, which reduces the cross-sectional area of ​​the exhaust flow channel 6002 through which the ventilation airflow must pass. The reduction in cross-sectional area impedes the flow of gas and prevents or minimizes an increase in flow that would otherwise result from a higher pressure in the pressurized volume 6000 relative to atmosphere 6100 .

[0292] Figure 9G The deflection of the membrane 3450 during treatment using a high treatment pressure is shown. As shown, during respiratory therapy, ventilation airflow 6203 flows through the movable portion 3456 of the membrane 3450 between the movable portion 3456 and the membrane-facing surface 3424 of the ventilation housing 3402. The lower pressure generated by the higher velocity of the air in the exhaust flow channel 6002 compared to the air on the opposite side of the membrane 3450 causes the movable portion 3456 of the membrane 3450 to deflect toward the membrane-facing surface 3424. As shown, the membrane 3450 contracts so that the central portion (along the length of the membrane 3450) is closer to the membrane-facing surface 3424 and the ventilation airflow must pass through a smaller cross-sectional area, thereby restricting the ventilation airflow of gas.

[0293] At lower treatment pressures (e.g., 6 cmH2O), the pressure differential between the pressurized volume 6000 and the atmosphere 6100, and the flow rate of the ventilation gas stream, will be lower than at higher treatment pressures. The velocity of the ventilation gas stream through the exhaust flow channel 6002 will still result in a low pressure area on one side of the movable portion 3456 of the membrane 3450, but the pressure differential across the movable portion 3456 will not be as great as at higher treatment pressures. Consequently, the movable portion 3456 of the membrane 3450 will be forced to move into the exhaust flow channel 6002 and toward the membrane-facing surface 3424 with less force than at higher treatment pressures. This results in less resistance to the exhaust flow of gas at lower treatment pressures.

[0294] Figure 9F Shows the use of Figure 9G34. The deflection of the membrane 3450 during treatment at a lower treatment pressure is shown. A low pressure region is still created between the movable portion 3456 of the membrane 3450 and the membrane-facing surface 3424, but the pressure differential created between the interior and exterior of the membrane 3450 is not as great as the pressure differential created during use of the ventilation system 3400 with a higher treatment pressure. Therefore, as shown, the movable portion 3456 of the membrane 3450 does not deflect as much as during treatment at a higher pressure.

[0295] The movable portion 3456 of the membrane 3450 is configured to impede ventilation airflow to an extent that depends on the therapeutic pressure and to regulate ventilation airflow throughout the therapeutic pressure range. Thus, the ventilation system 3400 is able to maintain a substantially constant ventilation flow rate over a typical range of therapeutic pressures. Because the ventilation system 3400 can provide this functionality, less reliance can be placed on the RPT device 4000 itself to regulate and maintain the desired therapeutic pressure and ventilation flow rate. Thus, the RPT device 4000 requires less complex hardware than RPT devices used in conventional ventilation systems because it is less reliant on regulating flow and pressure. Additionally, the RPT device 4000 requires less complex control features because it is also less reliant on regulating flow and pressure.

[0296] Figure 8 A graph depicts the flow rate of ventilation airflow through an exemplary ventilation system 3400 for a range of therapeutic pressures. As shown, within the therapeutic pressure range of 4 to 25 cmH2O, the flow rate of ventilation airflow does not increase with pressure throughout the therapeutic pressure range. Instead, the flow rate increases slightly within the therapeutic pressure range and then decreases slightly, regulating the ventilation airflow to a near constant flow rate within the therapeutic pressure range.

[0297] 5.3.4.2.3 Structure of movable parts

[0298] exist Figure 9A In the example of the present technology shown in FIG-D, the movable portion 3456 of the membrane 3450 is substantially cylindrical. Forming the movable portion 3456 of the membrane 3450 into a cylindrical form can allow the vent housing 3402 to have a smaller overall diameter than a vent housing including a membrane having a planar form. In other forms of the present technology, for example Figure 10A In the vent system 3400 shown in Figures 11-D and 11A-D, the movable portion 3456 of the membrane 3450 includes a frustoconical shape. The frustoconical movable portion 3456 of the membrane 3450 can also allow the vent housing 3402 to be narrower than when a planar membrane is incorporated. Compared to a planar annular membrane (e.g., a disk-shaped membrane with a central hole), the tubular membrane can result in a smaller overall diameter of the vent housing.

[0299] In these examples of the present technology, the membrane 3450 and the movable portion 3456 have a longitudinal axis 3454 that is aligned substantially parallel to the direction of gas flow received and / or supplied from the RPT device 4000 to the patient interface 3000. Additionally, the movable portion 3456 of the membrane 3450 includes a wall that is aligned parallel to the flow of gas through the ventilation housing 3402 from the first end 3404 of the ventilation housing 3402 to the second end 3405 of the ventilation housing 3402. In this example, the movable portion 3456 of the membrane 3450 includes a single cylindrical wall having a longitudinal axis 3454 that is aligned parallel to the direction of gas flow through the ventilation housing 3402 from the first end 3404 of the ventilation housing 3402 to the second end 3405 of the ventilation housing 3402. In other examples, the movable portion 3456 of the membrane 3450 may include multiple walls, such as two, three, or more walls. The walls may be non-planar and comprise a plurality of discrete lobes connected at their edges, or may be planar and comprise a plurality of discrete planar walls forming a hexagon, octagon, or the like.

[0300] Because the movable portion 3456 of the membrane 3450 includes walls aligned parallel to the airflow through the ventilation housing 3402, the movable portion 3456 may be less susceptible to acoustic noise traveling through the ventilation system 3400. Acoustic noise that propagates parallel to the airflow (e.g., noise generated by the patient 1000 that travels back along the flow path from the patient interface 3000 or noise generated by the RPT device 400 that travels downstream along the flow path) may generally propagate in a direction parallel to the walls of the movable portion 3456 of the membrane 3450. The movable portion 3456 of the membrane 3450, including walls aligned parallel to the direction in which pressure oscillations caused by the acoustic noise propagate, may be less susceptible to vibrations caused by the noise than walls aligned perpendicular to the propagation direction. That is, walls aligned parallel to the airflow through the ventilation system 3400 may be less susceptible to noise than walls aligned perpendicular to the airflow through the ventilation system 3400. Thus, the movable portion 3456 of the membrane 3450 can transmit low acoustic noise levels, at least compared to a movable portion 3456 of the membrane 3450 having walls perpendicular to the flow, such as a planar annular membrane (e.g., a disk shape with a central hole). The ventilation system 3400 can thus be relatively quiet, or at least quieter than alternative arrangements.

[0301] The movable portion 3456 of the membrane 3450 can be formed from silicone. In other examples, the movable portion 3456 of the membrane 3450 can be formed from another suitable material, such as rubber or a thermoplastic elastomer.

[0302] The membrane 3450 may be mounted on the exterior of the membrane facing surface 3424, such as Figures 9C-9G, 10C and 10D. In these examples, the movable portion 3456 of the membrane 3450 is disposed around the membrane-facing surface 3424. In these examples, the membrane 3450 and the membrane-facing surface 3424 are concentric, for example, they share a common axis.

[0303] exist Figures 9A to 9G 10A to 10D, the movable portion 3456 of the membrane 3450 is configured to move inward to restrict ventilation airflow. More specifically, the movable portion 3456 of the membrane 3450 can be configured to contract to move inward toward the membrane-facing surface 3424. In other examples of the present technology, for example Figures 11A to 11D 12A to 12D examples, the movable portion 3456 of the membrane 3450 is configured to move outwards toward the surface facing the membrane. However, in the ventilation system 3400 with a cylindrical or truncated cone membrane 3450, the advantage of the movable portion 3456 of the membrane 3450 moving inwards (e.g., shrinking) is that the movement does not cause hoop stress in the movable portion 3456 of the membrane 3450. That is, when the movable portion 3456 moves radially inwards, the cylindrical membrane 3450 is deformable into an hourglass shape. Therefore, it may be necessary to have a smaller force (e.g., a smaller difference in pressure on the membrane 3450) to realize the inward movement of the membrane 3450 relative to the outward movement. The increased hoop stress can also make the movable portion 3456 of the membrane 3450 more unstable when moving outwards than when moving inwards. Figure 9F and 9G The membrane 3450 is shown deflected by different amounts. Figure 9F As shown, the movable portion 3456 of the membrane 3450 has moved a smaller amount toward the membrane-facing surface 3424 (as might occur during treatment with a lower treatment pressure), while Figure 9G The movable portion 3456 of the middle membrane 3450 has moved a larger amount toward the membrane-facing surface 3424 (as might occur during treatment with higher treatment pressures).

[0304] While inward movement of the membrane 3450 may be advantageous, the present technology includes a vent system 3400 that includes a membrane 3450 having a movable portion 3456 that moves outward toward a surface facing the membrane. In this example, for example Figures 11A to 11D 12A to 12D , the movable portion 3456 of the membrane 3450 may be supported inside the membrane-facing surface 3424. Thus, the movable portion 3456 of the membrane 3450 may move outward to restrict ventilation airflow. The movable portion 3456 of the membrane 3450 may be configured to expand to move toward the membrane-facing surface 3424. If the membrane 3450 has a cylindrical shape, the membrane 3450 may bulge outward when the movable portion 3456 moves radially outward.

[0305] In some examples, the membrane 3450 can include a planar structure. While a generally tubular membrane 3450 provides some advantages to the vent system 3400, other advantageous features of a vent system 3400 according to the present technology can be applied to a vent system 3400 having a planar membrane 3450. For example, a trapped air cavity 6040, a damping chamber 6050, and / or a vent housing 3402 (as described herein) that reduces vibration of the membrane 3450 in modes higher than the first mode are features that can be applied to a vent system 3400 having a planar membrane. One example of a planar membrane 3450 is a disk (e.g., in the shape of a flat washer) with a central hole.

[0306] 5.3.4.3 Membrane stopper

[0307] The vent housing 3402 can be configured to limit movement of the movable portion 3456 of the membrane 3450 toward the membrane-facing surface 3424. Preventing the movable portion 3456 of the membrane 3450 from moving too far toward the membrane-facing surface 3424 can advantageously prevent excessive resistance to vent airflow or occlusion of the exhaust flow channel 6002.

[0308] The vent housing 3402 can contact the end of the membrane 3450 and prevent the end of the membrane 3450 from moving toward the membrane-facing surface 3424. The vent housing 3402 can include or provide one or more membrane stops configured to limit movement of the movable portion 3456 of the membrane 3450. Figures 9A to 9G , 10A to 10D, 11A to 11D, and 12A to 12D, the vent housing 3402 contacts the second end 3452 of the membrane 3450 and prevents the second end 3452 of the membrane 3450 from moving toward the membrane-facing surface 3424. In this example, the vent housing 3402 includes at least one protrusion 3444 that is configured to contact an end of the membrane 3450 to limit movement of the end of the membrane 3450, such as the second end 3452 of the membrane 3450.

[0309] The vent housing 3402 may include a plurality of protrusions 3444. The protrusions 3444 may be referred to as stops. In other examples, the vent housing 3402 may include other types of membrane stops, such as an inner ring that contacts the movable portion before the membrane 3450 and has a plurality of holes or other openings to allow air to flow into the exhaust flow channel 6002 or into the damping chamber 6050. In a further example, a membrane stop may be provided to the membrane 3450 itself. Further, in some examples, the membrane 3450 may be configured to limit its own movement or have an end that is substantially immovable or deformable. In one example, the free end of the membrane 3450 may include a substantially rigid portion that is immovable and moves toward the surface 3424 facing the membrane.

[0310] exist Figures 9A to 9G In the examples shown in Figures 10A to 10D, one or more protrusions 3444 are positioned outside the exhaust flow channel 6002. Because the protrusions 3444 are positioned outside the exhaust flow channel 6002, in these examples, the ventilation airflow does not bypass or pass between the protrusions 3444 as it flows into the atmosphere 6100. An advantage of positioning the plurality of protrusions 3444 outside the exhaust flow channel 6002 is that the protrusions 3444 do not disrupt the flow. In examples where the protrusions 3444 are positioned within the exhaust flow, there is the possibility that the protrusions 3444 in the flow path may create wakes in the ventilation airflow downstream of the protrusions, thereby generating turbulence that may increase the noise level of the ventilation system 3400. Furthermore, the turbulent airflow may cause the movable portion 3456 of the membrane 3450 to resonate or otherwise vibrate, which may further increase the noise level of the ventilation system 3400.

[0311] exist Figures 9A to 9G In the exemplary vent system 3400 shown in Figures 10A to 10D, the second housing member 3440 includes a plurality of protrusions 3444. The protrusions 3444 can be located within the interior of the membrane 3450. In these examples, the protrusions 3444 protrude toward the first end 3404 of the vent housing 3402. The second housing member 3440 can include an inwardly extending membrane retaining flange 3446 on which the protrusions 3444 are disposed. The protrusions 3444 can protrude from the membrane retaining flange 3446 in a direction toward the first end 3404 of the vent housing 3402. One or more of the protrusions 3444 can contact the inner surface of the membrane 3450 at the second end 3452 of the membrane 3450. In this manner, inward movement of the second end 3452 of the membrane 3450 is limited by the protrusions 3444.

[0312] In an alternative example of the technology, the vent housing 3402 may include only one protrusion 3444, for example in the form of one or more lips configured to fit within or around the second end of the membrane 3450. However, an advantage of multiple protrusions 3444 is that multiple protrusions 3444 can define openings between adjacent pairs. The protrusions 3444 may include damping orifices 6055 therebetween, as will be discussed in greater detail below.

[0313] The protrusion 3444 is advantageously positioned outside of the vent flow, although in some examples, the protrusion 3444 or other membrane stop may be positioned inside the vent flow, such as within the exhaust flow channel 6002 . Figure 11C 、 11DThe example vent system 3400 shown in 12C and 12D includes a protrusion 3444 disposed on the membrane-facing surface 2424. The protrusion 3444 can be in the form of a stop, a protrusion, a bump, a standoff, a tongue, etc. The protrusion 3444 contacts a corresponding portion of the movable portion 3456 of the membrane 3450 to hold the movable portion 3456 away from the membrane-facing surface 3424, thereby preventing occlusion of the exhaust flow channel 6002.

[0314] The at least one protrusion 3444 may be provided on the first housing member 3430. Figures 11A to 12D In the examples of FIG. 34 , a plurality of protrusions 3444 are provided on the inner surface of the first shell member 3430 to limit the movement of the second end 3452 of the membrane 3450 toward the membrane-facing surface 3424 of the first shell member 3430. In these examples, the protrusions 3444 are provided from the cylindrical portion (in the inner surface) of the first shell member 3430. Figures 12A to 12D in the example) or conical (in Figures 11A to 11D The protrusion 3444 may contact the outer surface of the membrane 3450 at the second end 3452 of the membrane 3450.

[0315] 5.3.4.4 Membrane support

[0316] The vent system 3400 can include a membrane support 3460 on which the membrane 3450 is supported within the vent housing 3402. The membrane support 3460 can be a rigid structure supported by or in the vent housing 3402 that is configured to support the membrane and hold the first end 3451 of the membrane 3450 in place. In these examples, the membrane 3450 can be molded onto the membrane support 3460 at the first end 3451 of the membrane 3450. In other examples, the membrane 3450 can be molded onto the membrane support 3460 at the second end of the membrane 3450. In some examples of the technology, the membrane 3450 can be assembled to the membrane support 3460 without being permanently connected to the membrane support 3460. For example, the membrane 3450 can be assembled around the circumference of a cage or other substantially rigid structure.

[0317] In these examples, the membrane support 3460 can be configured to be coupled to the vent housing 3402. In these examples, the membrane support 3460 is configured to be coupled to the vent housing 3402 between the first end 3404 of the vent housing 3402 and the second end 3405 of the vent housing 3402. The membrane support 3460 can be configured to be coupled to a central portion of the vent housing 3402, such as Figures 9C-9G , 10C and 10D. Alternatively, as Figure 11C 、 11D, 12C and 12D, the membrane support 3460 may be configured to connect to the vent housing 3402, for example, at or near the first end 3404 of the vent housing 3402, towards the first end 3404 of the vent housing 3402. In some forms of the present technology, where the orientation of the membrane 3450 is reversed, the membrane support 3460 may be configured to connect to the vent housing 3402 towards (e.g., at or near) the second end 3405 of the vent housing 3402.

[0318] like Figures 9A to 9G As shown in the example of , the membrane support 3460 may include a connecting portion 3462 for connecting to the vent housing 3402. The connecting portion 3462 may be configured to connect directly or indirectly to the vent housing 3402. The connecting portion 3462 may be cylindrical and configured to fit around the exterior of the second housing member 3440. The connecting portion 3462 may be concentric with the membrane 3450.

[0319] The membrane support 3460 may include a membrane support flange 3464 extending inwardly from the inner surface of the connecting portion 3462 of the membrane support 3460 and configured to support the membrane 3450. The membrane support flange 3464 may be spaced apart from the end of the connecting portion 3462. The membrane 3450 may be molded onto the membrane support flange 3464. Figures 9A to 9G As shown in the example of FIG, a membrane support flange 3464 supports the membrane 3450 inside the vent housing. In this example, the first end 3451 of the membrane 3450 is fixed to and supported by the membrane support flange 3464. Thus, the membrane support flange 3464 supports the first end 3451 of the membrane 3450 inside the vent housing 3402, and the membrane 3450 extends from the membrane support flange 3464 toward the second end 3405 of the vent housing 3402.

[0320] The membrane support 3460 may include a baffle portion 3465, such as Figures 11A to 11D and 12A to 12D. The baffle portion 3465 is configured to protect one side of the membrane 3450 from gas flow through the center of the vent housing 3402. In these examples, the movable portion 3456 of the membrane 3450 moves outward toward the membrane-facing surface 3424 to restrict gas flow through the exhaust flow channel 6002. In these examples, the baffle portion 3465 is cylindrical. In other examples, the baffle portion 3465 can be frustoconical, bell-shaped, or any other suitable shape. The baffle portion 3465 can be concentric with the movable portion 3456 of the membrane 3450. In these examples, the baffle portion 3465 is disposed radially inwardly of the movable portion 3456 of the membrane 3450. As Figures 11A to 12DAs shown in the example of , the baffle portion 3465 has a first end 3466 connected to the movable portion 3456 of the membrane 3450 at the first end 3451 of the membrane 3450. In addition, the baffle portion 3465 has a second end 3467 provided toward the second end 3452 of the membrane 3450, for example at or near the second end 3452 of the membrane 3450.

[0321] exist Figures 11A to 11D In the example shown, the baffle portion 3465 includes a baffle flange 3468 at a second end 3467 of the baffle portion 3465. In this example, the baffle flange 3468 extends outwardly from the baffle portion 3465. The baffle flange 3468 may partially define the exhaust flow channel inlet 6004 to the exhaust flow channel 6002.

[0322] The rounded surface 3433 at or near the exhaust flow channel inlet 6004 may be a rounded edge of the membrane support 3460 at its second end. The rounded surface 3433 may be provided on the baffle flange 3468 of the membrane support 3460, as shown in FIG. Figures 11A to 11D shown.

[0323] The damping chamber 6050 can be defined in part by the baffle portion 3465 of the membrane support 3460. The damping chamber 6050 can be defined in part by an outwardly extending flange of the baffle portion 3465.

[0324] 5.3.4.5 Exhaust flow

[0325] The ventilation air flow may flow radially outward at or near the inlet of the exhaust flow channel 6002. Figures 9A to 9G , 10A to 10D, 11A to 11D, and 12A to 12D, and specifically see Figure 9E 6201 from the RPT device 4000 to the patient interface 3000 flows in an axial direction through the ventilation housing 3402 (with various air flows shown). Furthermore, a portion of the airflow 6201 entering the ventilation housing 3402 becomes a ventilation airflow 6203 flowing in a radial direction at or near the inlet of the exhaust flow channel 6002. The direction of the airflow within the ventilation housing 3402 can be changed from an axial direction to a radial direction to generate the ventilation airflow 6203. The exhaust flow 6203 can be changed from the radial direction to an axial direction aligned with the longitudinal axis of the ventilation system 3400 simultaneously with or before passing through the inlet to the exhaust flow channel 6002. The ventilation airflow in the exhaust flow channel 6002 can flow parallel to the longitudinal axis 3406 of the ventilation housing 3402 and / or the longitudinal axis 3454 of the membrane 3450.

[0326] As discussed in more detail above, the vent housing 3402 can include a rounded surface 3433 at or near the inlet of the exhaust flow passage 6002 (e.g., at the exhaust flow passage inlet 6004). The rounded surface 3433 can be configured to facilitate a change in the direction of the vent airflow prior to entering the exhaust flow passage 6002. More generally, the vent housing 3402 can include an exhaust flow passage 6002 having an exhaust flow passage inlet 6004 that is shaped to avoid significant resistance to airflow entering the exhaust flow passage 6002. This shape can be achieved by the rounded surface 3433 on the first housing member 3430 or another portion of the vent housing 3402 or one of the components of the vent system 3400 (e.g., Figures 11A to 11D This is achieved by a circular or other contoured surface on the second shell member 3440 in the example.

[0327] The exhaust flow passage inlet 6004 may be an annular opening in the breather housing 3402. For example, Figures 9A to 10D In the example shown, the exhaust flow passage inlet 6004 is a single opening into the exhaust flow passage 6002 around the exterior of the first housing member 3430. The first housing member 3430 and the membrane 3450 are concentric with each other, but at the second end 3432 of the first housing member 3430, the membrane 3450 has an inner diameter that is larger than the outer diameter of the first housing member 3430, thereby providing a gap that forms the exhaust flow passage inlet 6004.

[0328] In some examples, the exhaust flow passage inlet 6004 may also be defined by the axial spacing between components. Figures 9A to 10D In the example shown, the opening forming the exhaust flow passage inlet 6004 is also provided by the axial spacing between a portion of the first housing member 3430 and a portion of the second housing member 3440 within the interior of the breather housing 3402. Figures 11A to 11D In the example shown, the exhaust flow channel inlet 6004 is primarily formed by the axial spacing between a portion of the membrane support 3460 and the breather housing 3402. Figures 11A to 11D In the example shown in FIG. 5 , the exhaust flow channel inlet 6004 is formed by the spacing between the membrane support 3460 and the second housing member 3440 in the axial direction.

[0329] exist Figures 12A to 12DIn the example shown, the breather housing 3402 includes a plurality of exhaust flow passage inlets 6004. In this example, the plurality of exhaust flow passage inlets 6004 are formed in the membrane support 3460, specifically in the baffle portion 3465. In other examples, the plurality of exhaust flow passage inlets 6004 may be provided elsewhere. For example, the plurality of exhaust flow passage inlets 6004 may be provided through openings formed in the baffle flange 3468. In yet other examples, the plurality of exhaust flow passage inlets 6004 may be provided through openings formed in the first housing member 3430 (e.g., in the shaft 3434).

[0330] The vent housing 3402 can include a plurality of exhaust apertures 3471, 3472 configured to allow exhaust to pass to the atmosphere 6100. The exhaust apertures can be spaced around the circumference of the vent housing 3402. The vent housing 3402 can include at least one diffused exhaust aperture 3471 and at least one undiffused exhaust aperture 3472. In the examples of Figures 9 and 11, the vent housing 3402 includes a plurality of diffused exhaust apertures 3471 and a plurality of undiffused exhaust apertures 3472.

[0331] The ventilation system 3400 may include a diffuser member 3474 configured to diffuse and / or audibly block the exhaust gas as it exits the ventilation system 3400. In other examples, the ventilation system 3400 may include multiple diffuser members 3474. The diffuser member 3474 may be formed from a fiber network through which the exhaust gas can be forced to follow a tortuous path, such as a felt material. Other materials that diffuse and / or audibly block the ventilation airflow may be used in the ventilation system 3400, such as open-cell foam.

[0332] The diffuser member 3474 can be positioned in series with (e.g., above or behind) the diffuser exhaust aperture 3471 to require gas flowing through the at least one diffuser exhaust aperture 3471 to flow through the diffuser member 3474. The at least one undiffused exhaust aperture 3472 can be open (e.g., not blocked by a diffuser member).

[0333] like Figures 9A to 9G , 11A to 11D and 12A to 12D, and with specific reference to the particular gas flow paths and diffuser member 3474 shown. Figure 9E , the ventilation system 3400 provides a diffused ventilation flow path through which exhaust gas can be vented through the diffuser member 3474 and at least one diffused exhaust orifice 3471. The diffused flow of gas in Figure 9E In the 6204. Figures 9A to 9GIn the examples of FIG. 11A through FIG. 11D , the ventilation system 3400 provides an undiffused ventilation flow path through which exhaust gas can be vented through the at least one undiffused exhaust orifice 3472 . Figure 9E Indicated by 6205.

[0334] The vent system 3400 can be configured to allow exhaust gas to flow through the at least one non-diffused exhaust aperture 3472 in the event that exhaust gas is unable to flow through the diffuser member 3474 and the at least one diffused exhaust aperture 3471. Advantageously, Figures 9A to 9G The vent system 3400 of the examples of FIG. 11A through FIG. 11D is capable of venting exhaust in the event that the diffuser member 6474 becomes clogged, blocked, or otherwise fails to allow adequate ventilation airflow therethrough. Figure 9E As shown, ventilation airflow 6203 flows through exhaust flow channel 6002. Ventilation airflow 6203 can then flow through diffuser member 3474 and flow to atmosphere 6100 as diffused ventilation airflow 6204, or bypass diffuser member 3474 and flow directly to atmosphere 6100 as un-diffused ventilation airflow 6205. The path taken by the ventilation airflow can depend on whether diffuser member 3474 is blocked.

[0335] exist Figures 9A to 9G 11A through 11D, when the diffuser member 3474 is unobstructed and capable of allowing sufficient ventilation flow through the diffused exhaust apertures 3471, the vent housing 3402 provides a relatively high resistance to ventilation flow through the undiffused exhaust apertures 3472 compared to the diffused exhaust apertures 3471. Thus, when the diffuser member 3474 is in an operating state (e.g., unobstructed), a majority of ventilation flows through the diffuser member 3474 and through the diffused exhaust apertures 3471 as diffused ventilation airflow 6204. When the diffuser member 3474 is obstructed and its resistance to gas flow increases, the vent housing is still capable of allowing ventilation flow through the undiffused exhaust apertures 3472 as undiffused ventilation airflow 6205.

[0336] The breather housing 3402 can be shaped to require the exhaust flow to change direction to a greater extent to flow through the at least one non-diffused exhaust aperture 3472 rather than through the diffused exhaust apertures 3471. The additional change in direction required to flow out of the non-diffused exhaust apertures 3472 provides sufficient resistance so that the gas flows through the diffuser member 3474 instead of the non-diffused exhaust apertures 3472. That is, the breather housing 3402 can be shaped to require the exhaust flow to change direction to flow through the non-diffused exhaust apertures 3472 to a sufficient extent so that a majority of the exhaust flow flows through the diffuser member 3474 and through the diffused exhaust apertures 3471 unless the diffuser member 3474 becomes clogged.

[0337] like Figure 9C and 9D As shown, the vent housing 3402 can be shaped to require the exhaust flow to change direction by approximately 90 degrees to flow through the one or more diffused exhaust apertures 3471. The vent housing 3402 can be shaped to require the exhaust flow to change direction by more than 90 degrees to flow through the one or more non-diffused exhaust apertures 3472, as shown. Figure 9C and 9D In various examples, the breather housing 3402 may be shaped to require the exhaust flow to change direction by greater than 110, 130, or 150 degrees to flow through the one or more undiffused exhaust apertures 3472 .

[0338] The diffused exhaust apertures 3471 and the undiffused exhaust apertures 3472 may be spaced longitudinally along the length of the vent housing 3402. Figures 9A to 9G 11A through 11D, the diffused exhaust apertures 3471 are positioned toward, e.g., at or near, the first end 3404 of the breather housing 3402. In these examples, the undiffused exhaust apertures 3472 are centrally located between the first end 3404 of the breather housing 3402 and the second end 3405 of the breather housing 3402.

[0339] The diffused exhaust apertures 3471 can open in a lateral (i.e., radial) direction relative to the breather housing 3402. As the exhaust spreads out over a progressively larger area as it travels out of the breather housing 3402, the exhaust can be highly diffused after being vented from the circumferentially laterally open apertures of the breather housing 3402. The undiffused exhaust apertures 3472 can open partially laterally and partially toward the second end 3405 of the breather housing 3402, i.e., at an oblique angle to the longitudinal axis of the breather housing 3402.

[0340] In some examples, the ventilation system 3400 can include a diffuser member 3474 configured to diffuse and / or audibly shield an exhaust flow of gas and can include one or more common exhaust orifices 3473 through which the ventilation airflow can flow to the atmosphere 6100 regardless of whether the diffuser member 3474 allows flow within itself.

[0341] like Figures 10A to 10DAs shown, the vent system 3400 includes a first housing member 3430 including a flange 3435 and a diffuser retaining lip 3437. A diffuser member 3474 is held in place by the flange 3435 and the diffuser retaining lip 3437. The diffuser member 3474 is positioned adjacent to but spaced apart from the membrane support 3460 in the airflow path through the exhaust flow channel 6002 downstream of the membrane 3450. When the diffuser member 3474 is unobstructed, the vent system 3400 in this example includes a low resistance flow path through the material of the diffuser member 3474 and then out of the common exhaust orifice 3473. In addition, the ventilation system 3400 in this example includes a high resistance flow path (when the diffuser member 3474 is unobstructed) in which the flow of gas must suddenly change direction downstream of the membrane 3450 (in this example at the first end 3451 of the membrane 3450) and flow through the diffuser member 3474 and out to the atmosphere through the common exhaust orifice 3473.

[0342] exist Figures 10A to 10D During normal operation of the illustrated vent system 3400, when the diffuser member 3474 is unobstructed, the majority of the gas vent flow will take the low resistance flow path through the diffuser member 3474. If the diffuser member 3474 becomes obstructed or does not allow sufficient flow through, the vent system 3400 can still function as an alternative flow path through which exhaust gas can flow past the diffuser member 3474, which becomes the low resistance flow path when the diffuser member 3474 becomes obstructed.

[0343] The vent system 3400 may include at least one intermediate exhaust orifice 3478 upstream of the diffuser member 3474. Figures 12A to 12D In the example of FIG, the first housing member 3430 includes a plurality of intermediate exhaust apertures 3478. The intermediate exhaust apertures 3478 are disposed upstream of the diffuser member 3474. The intermediate exhaust apertures 3478 may or may not be covered by the diffuser member 3474. Figures 11A to 11D In the example shown, the diffuser member 3474 does not cover the intermediate exhaust apertures 3478 , such that the ventilation airflow can flow through the diffuser member 3474 and then through the diffused exhaust apertures 3471 , or through the diffuser member 3474 and then through the undiffused exhaust apertures 3472 .

[0344] exist Figures 12A to 12DIn the example shown, diffuser member 3474 covers intermediate exhaust apertures 3478. In this example, diffuser member 3474 is substantially cylindrical in shape to fit around a portion of vent housing 3402. Diffuser member 3474 covers these intermediate exhaust apertures 3478 to diffuse and / or audibly shield the vent air flow released therefrom. Gas can be discharged to the atmosphere through diffused exhaust apertures 3471 through diffuser member 3474.

[0345] exist Figures 12A to 12D In the example shown, a diffused exhaust aperture 3471 is also formed by a gap between a portion of the first housing member 3430 and the first end 3441 of the second housing member 3440. In general, in any example of the present technology, an exhaust aperture (diffused or non-diffused) can be formed by a hole or opening formed in a single component of the vent housing 3402 (e.g., the first housing member or the second housing member), or by a gap formed between multiple components of the vent housing 3402.

[0346] Second housing member 3440 can include a diffuser retaining portion 3448. In this example, diffuser retaining portion 3448 is in the form of a cylindrical sleeve configured to fit over first housing member 3430. In this example, first housing member 3430 also has a substantially cylindrical second housing member connecting portion 3438 at second end 3432 of first housing member 3430, and a diffuser retaining lip 3437 in the form of a flange at second end 3432 of first housing member 3430. In this example, diffuser member 3474 is retained in the passageway of first housing member 3430 between diffuser retaining lip 3437 and second housing member connecting portion 3449, while being held radially in place by diffuser retaining portion 3448 of second housing member 3440.

[0347] exist Figures 12A to 12D In the example, the diffuser exhaust aperture 3471 formed by the gap between the first shell member 3430 and the second shell member 3440 is formed by the gap between the diffuser retaining portion 3448 of the second shell member 3440 and the diffuser retaining edge 3437 of the first shell member 3430.

[0348] 5.3.4.6 Exhaust port components

[0349] The ventilation system 3400 can include an exhaust orifice member 3470 including the one or more exhaust orifices through which the ventilation airflow can exit the ventilation system 3400 to the atmosphere 6100 .

[0350] Figures 9A to 9GThe ventilation system 3400 shown in Figures 11A to 11D includes an exhaust orifice member 3470. In these examples, the exhaust orifice member 3470 includes a plurality of exhaust orifices. The at least one diffused exhaust orifice 3471 can be provided toward a first end 3476 of the exhaust orifice member 3470, for example, at or near the first end 3476 of the exhaust orifice member 3470. In these examples, the diffused exhaust orifice 3471 is substantially located at the first end 3476 of the exhaust orifice member 3470. The one or more non-diffused exhaust orifices 3472 can be provided toward a second end 3477 of the exhaust orifice member 3470, opposite the first end 3476 of the exhaust orifice member 3470, for example, at or near the second end 3477 of the exhaust orifice member 3470. Figures 9A to 9G The exhaust orifice member 3470 of the ventilation system 3400 shown includes a plurality of diffused exhaust orifices 3471 toward a first end 3476 of the exhaust orifice member 3470 (e.g., at or near the first end 3476) and a plurality of undiffused exhaust orifices 3472 toward a second end 3477 of the exhaust orifice member 3470 (e.g., at or near the second end 3477).

[0351] The exhaust aperture member 3470 can be configured to be connected to the first housing member 3430, such as Figures 9A to 9G and 11A to 11D examples. The exhaust orifice member 3470 can be formed in the shape of a ring. In the example of Figure 9, a diffuse exhaust orifice 3471 is formed in the exhaust orifice member 3470 to open laterally and radially outward from the axis of the exhaust orifice member 3470. In addition, an undiffused exhaust orifice 3472 is formed in the exhaust orifice member 3470 to open in a partially radial and partially axial direction relative to the exhaust orifice member 3470. In this example, the undiffused exhaust orifice 3472 opens in a direction that is oblique to the lateral direction in which the diffuse exhaust orifice 3471 opens. As described in more detail above, the different opening directions of these exhaust orifices contribute to the resistance of these different flow paths that the ventilation flow may take to flow out of the ventilation system 3400.

[0352] exist Figures 9A to 9G 11A-11D, the diffuser member 3474 is retained in the vent system 3400 by the exhaust aperture member 3470. In these examples, the diffuser member 3474 is housed between the exhaust aperture member 3470 and the first housing member 3430.

[0353] exist Figures 9A to 9GIn the illustrated example vent system 3400, an exhaust orifice member 3470 and a membrane support member 3460 are configured to connect together to connect the first housing member 3430 and the second housing member 3440. Specifically, a connecting portion 3462 of the membrane support member 3460 is configured to connect to the exhaust orifice member 3470. The connecting portion 3462 of the membrane support member can be configured to form a press-fit connection with the exterior of the exhaust orifice member 3470. When the membrane support member 3460 is connected to both the exhaust orifice member 3470 and the second housing member 3440, a membrane support flange 3464 can be located between the exhaust orifice member 3470 and the second housing member 3440.

[0354] 5.3.4.7 Vibration reduction

[0355] 5.3.4.7.1 Damping structure

[0356] exist Figures 9A to 10D The ventilation system 3400 in the examples includes a damping structure configured to damp vibrations of the movable portion 3456 of the membrane 3450. In these examples, the damping structure includes a damping chamber 6050 within the ventilation housing 3402. By damping vibrations of the movable portion 3456, the damping chamber 6050 can reduce noise generated by the membrane 3450 and emitted by the ventilation system 3400. The damping chamber 6050 can contain entrapped air (or other breathable gas). The damping chamber 6050 in these examples is a entrapped air cavity.

[0357] The vent housing 3402 may partially define the damping chamber 6050. Additionally, the membrane 3450 may partially define the damping chamber 6050. Figures 9C-9G , 10C, and 10D, the damping chamber 6050 is a cavity disposed on the outside of the membrane 3450 that, in use, is in fluid communication with the pressurized volume 6000 and is filled with a gas having the same pressure as the pressurized volume 6000 when the membrane 3450 is at rest. The movable portion 3456 of the membrane includes a first side facing the membrane surface 3424 and a second side, opposite the first side, that partially defines the damping chamber 6050. The damping chamber 6050 can be further defined by one or more walls of the second housing member 3440. In various examples, one of the interior and exterior of the movable portion 3456 of the membrane 3450 faces the membrane-facing surface 3424, and the other of the interior and exterior of the movable portion 3456 of the membrane 3450 partially defines the damping chamber 6050.

[0358] The vent system 3400 can be configured such that movement of the movable portion 3456 of the membrane 3450 increases or decreases the volume of the damping chamber 6050. Changing the volume of the damping chamber 6050 reduces the amount of air that can occupy the damping chamber 6050 at a particular pressure.

[0359] In these examples, the vent housing 3402 and the damping chamber 6050 are configured to damp vibrations of the movable portion 3456 of the membrane 3450 by limiting the exchange of gas between the damping chamber 6050 and the pressurized volume 6000. As the movable portion 3456 of the membrane 3450 moves, the restriction in the exchange of gas between the damping chamber 6050 and the pressurized volume 6000 provides a damping effect on the membrane 3450, thereby causing the volume of the damping chamber 6050 to increase or decrease. Figures 9C-9G As shown, the ventilation system 3400 may include at least one damping orifice 6055 through which gas can flow into and out of the damping chamber 6050. The damping chamber flow of gas entering the damping chamber 6050 is Figure 9F and 9G Indicated by 6206 . The damping orifice 6055 may be shaped and / or sized to resist gas exchange between the damping chamber 6050 and the pressurized volume 6000 .

[0360] If the movable portion 3456 of the membrane 3450 begins to move away from the membrane-facing surface 3424, which causes the volume of the damping chamber 6050 to decrease, the restriction of air flow out of the damping chamber 6050 causes the air pressure within the damping chamber 6050 to increase. This increase in pressure in the damping chamber 6050 acts on the movable portion 3456 of the membrane 3450 to slow its movement away from the membrane-facing surface 3424.

[0361] Conversely, if the movable portion 3456 of the membrane 3450 begins to move toward the membrane-facing surface 3424, which causes the volume of the damping chamber 6050 to increase, the restriction of airflow into the damping chamber 6050 causes the air pressure within the damping chamber 6050 to decrease. This pressure reduction in the damping chamber 6050 acts on the movable portion 3456 of the membrane 3450 to slow its movement toward the membrane-facing surface 3424.

[0362] In these examples, the restriction of gas flow between the pressurized volume 6000 and the damping chamber 6050 is not a complete occlusion that prevents all gas exchange. The restriction of gas exchange into or out of the damping chamber 6050 can slow and / or smooth the movement of the movable portion 3456 of the membrane 3450. However, the restriction of gas exchange will allow movement of the movable portion 3456 of the membrane 3450 that is caused by non-vibrational forces because the pressure difference between the pressurized volume 6000 and the damping chamber 6050 will equalize over time. For example, if a constant force is applied to the movable portion 3456 of the membrane 3450 toward the membrane-facing surface 3424, the damping chamber 6050 can initially slow and / or smooth the movement of the movable portion 3456 of the membrane 3450 toward the membrane-facing surface 3424. As gas slowly enters the damping chamber 6050, as Figure 9GAs shown in FIG. 6A and FIG. 6B , the pressure in the damping chamber 6050 will equalize with the pressure in the pressurized volume 6000. The movable portion 3456 of the membrane 3450 will then occupy a position closer to the membrane-facing surface 3424 without being pulled back by the lower pressure in the damping chamber 6050. Thus, a damping effect is provided that resists and / or smooths out unwanted movement (e.g., vibrations that may be noisy) of the movable portion 3456 of the membrane 3450.

[0363] As described above, the vent system 3400 can include at least one damping orifice 6055. The at least one damping orifice 6055 can have a size small enough to resist some gas exchange between the damping chamber 6050 and the pressurized volume 6000. The damping orifice 6055 in the vent system 3400 can have a size that is small enough to provide sufficient resistance to gas exchange, but not so small as to reduce the functionality of the vent system 3400 (e.g., the ability of the movable portion 3456 of the membrane 3450 to move toward or away from the membrane-facing surface 3424).

[0364] The actual size of each damping orifice 6055 in a particular ventilation system 3400 can be determined based on a number of factors, such as the number of damping orifices 6055, the size of the damping chamber 6050 and membrane 3450, the shape and size of the ventilation housing 3402, the shape and stiffness of the membrane 3450, and the treatment pressure. The appropriate size of each damping orifice 6055 can be determined based on simulations, simple experiments, and / or trial and error. The ventilation system 3400 can include a plurality of damping orifices 6055 through which gas can flow into and out of the damping chamber 6050. The plurality of damping orifices 6055 can together define a combined cross-sectional area through which gas can flow that is sufficiently small to resist gas exchange between the damping chamber 6050 and the pressurized volume 6000.

[0365] As described above, the vent housing 3402 includes a plurality of protrusions 3444 configured to prevent the free end of the membrane 3450 from moving toward the membrane-facing surface 3424. The vent housing 3402 may include the plurality of protrusions 3444 and a plurality of damping orifices 6055 defined between the plurality of protrusions 3444. Gas can flow into and out of the damping chamber 6050 from the pressurized volume 6000 through the damping orifices 6055 between the protrusions 3444, and the damping orifices 6055 prevent gas exchange between the damping chamber 6050 and the pressurized volume 6000 to dampen vibrations of the movable portion 3456 of the membrane 3450. Figures 9C to 9G 10C to 10D show that the protrusions 3444 have small gaps between them, which form damping orifices 6055 in these examples.

[0366] 5.3.4.7.2 Restrictions in the exhaust flow path

[0367] exist Figures 9A to 9G In the illustrated exemplary ventilation system 3400, exhaust flow channel 6002 includes an area having a smaller cross-sectional area than adjacent areas in exhaust flow channel 6002. In this example, exhaust flow channel 6002 includes a restriction 6006 in the exhaust flow path that forms an area having a smaller cross-sectional area. Exhaust flow channel 6002 has a smaller cross-sectional area at restriction 6006 than at other locations in exhaust flow channel 6002. Membrane-facing surface 3424 may be closer to movable portion 3456 of membrane 3450 at restriction 6006 than at other locations in exhaust flow channel 6002, resulting in a smaller cross-sectional area through which exhaust gas can flow.

[0368] The restriction 6006 in the exhaust flow passage 6002 may be formed by the restrictor portion 3425 as described above. Figures 9A to 9G In the example of FIG, the restriction 6006 is formed by a restrictor portion 3425 in the form of a contoured surface forming a rib on the first housing member 3430. The restrictor portion 3425 can be centrally located between the first end of the membrane 3450 and the second end of the membrane 3450.

[0369] The damping chamber 6050 may include a first end 6051 adjacent to the first end 3451 of the membrane 3450 and a second end 6052 adjacent to the second end 3452 of the membrane 3450. Figures 9A to 9G In the example shown, the restriction 6006 in the exhaust flow channel 6002 is centrally aligned between the first end 6051 and the second end 6052 of the damping chamber 6050. Additionally, in this example, the restriction 6006 in the exhaust flow channel 6005 is centrally aligned between the first end 3451 of the membrane 3450 and the second end 3452 of the membrane 3450. In this example, the restriction 6006 is centrally aligned along the longitudinal length of the movable portion 3456 of the membrane 3450.

[0370] Restriction 6006 creates an area of ​​exhaust flow channel 6002 with a minimum pressure (due to its minimum cross-sectional area according to Bernoulli's principle) compared to the pressure at other areas of exhaust flow channel 6002. Because the pressure in exhaust flow channel 6002 is minimum at restriction 6006, the force on membrane 3450 directed toward membrane-facing surface 3424 is greater at restriction 6006 than elsewhere along the length of membrane 3450. This point of maximum force on membrane 3450 forces movable portion 3456 of membrane 3450 to deform in a predictable manner. Moveable portion 3456 of membrane 3450 can predictably deflect to a greater degree near restriction 6006 than elsewhere in exhaust flow channel 6002. A membrane 3450 that deforms in this particular manner may be less susceptible to vibrations along its length than a membrane 3450 positioned along exhaust flow channel 6002 having a constant cross-section and pressure along its length. Low vibrations of the membrane 3450 may result in low noise levels emitted by the ventilation system 3400 and low fluctuations in pressure within the air circuit 4170 and / or the patient interface 3000 .

[0371] The vent housing 3402 can be configured so that any vibrations of the movable portion 3456 of the membrane 3450 that do occur will primarily occur in the first vibration mode. The central position of the restriction 6006 relative to the diaphragm 3450 can adjust the vibrations in the diaphragm 3450 to be primarily in the first vibration mode. While vibrations in the membrane 3450 will be minimized, it may be advantageous for any vibrations of the membrane 3450 that do occur to be primarily in the first vibration mode rather than in higher modes.

[0372] exist Figures 9A to 9G In the example shown, the damping chamber 6050 extends substantially along the entire length of the diaphragm 3450, with a first end 6051 of the damping chamber 6050 adjacent to the first end 3451 of the membrane 3450 and a second end 6052 of the damping chamber 6050 adjacent to the second end 3452 of the membrane 3450. This exemplary configuration has the effect that the first mode vibration of the membrane 3450 causes a volume change throughout the damping chamber 6050, and gas is forced into and out of the damping chamber 6050 through the damping orifices 6055 during vibration.

[0373] If the membrane 3450 vibrates in a higher mode, the change in volume of the damping chamber 6050, if any, may be less significant. For example, if the membrane 3450 vibrates in its second mode, there may be little or no overall change in the volume of the damping chamber 6050. The portion of the membrane 3450 between the first end 3451 and the center point of the membrane 3450 will move in one direction, while the portion of the membrane 3450 between the center point and the second end 3452 of the membrane 3450 will move in another direction. Any increase in the volume of one half of the damping chamber 6050 may be accompanied by a corresponding decrease in the volume of the other half of the damping chamber 6050. The gas within the damping chamber 6050 will move from one end of the damping chamber 6050 to the other end, rather than being forced through the damping orifice 6055. In such a configuration, there is a smaller damping effect, assuming that less gas is forced into and out of the damping chamber 6050.

[0374] The vent system 3400 is configured so that the membrane 3450 tends to vibrate primarily in its first mode, if at all, which can be relatively quiet due to the damping effect provided by the damping chamber 6050. In fact, even if the vent system 3400 tolerates some second or higher mode vibration, some vibration damping can still be achieved. Figures 10A to 10D The damping chamber 6050 shown in the vent system 3400 can provide a damping effect due to any first mode vibrations that do occur in the membrane 3450, even in the absence of restrictions in the exhaust flow path 6002. Additionally, third mode vibrations can affect the volume of the damping chamber 6050, resulting in a damping effect. Furthermore, even in the absence of restrictions in the exhaust flow path 6002, the damping chamber 6050 can act as a stagnant air cavity that is largely unaffected by airflow through the vent system 3400. Even in the absence of damping, the damping chamber 6050 provides a higher pressure on the membrane 3450 opposite the low pressure area in the exhaust flow path 6002, enabling the movable portion to move toward the membrane-facing surface 3424 to adjust the ventilation airflow.

[0375] 5.3.5 Decoupling Structure

[0376] In one form, the patient interface 3000 includes at least one decoupling structure, such as a swivel or a ball and socket.

[0377] 5.3.6 Connection Port

[0378] The connection port 3600 allows connection to the air circuit 4170 .

[0379] 5.3.7 Forehead support

[0380] In one form, the patient interface 3000 includes a forehead support 3700 .

[0381] 5.3.8 Anti-asphyxia valve

[0382] In one form, patient interface 3000 includes an anti-asphyxia valve.

[0383] 5.3.9 Port

[0384] In one form of the present technology, the patient interface 3000 includes one or more ports that allow access to the volume within the plenum chamber 3200. In one form, this allows the clinician to supply supplemental oxygen. In one form, this allows direct measurement of properties of the gas within the plenum chamber 3200, such as pressure.

[0385] 5.4RPT device

[0386] An RPT device 4000 according to one aspect of the present technology includes mechanical, pneumatic, and / or electrical components and is configured to execute one or more algorithms 4300, such as any of the methods described herein in whole or in part. The RPT device 4000 can be configured to generate a flow of air for delivery to the airway of a patient, such as for treating one or more respiratory conditions described elsewhere in this document.

[0387] In one form, the RPT device 4000 is constructed and arranged to deliver air flow in the range of -20 L / min to +150 L / min while maintaining a positive pressure of at least 6 cmH2O, or at least 10 cmH2O, or at least 20 cmH2O.

[0388] The RPT device 4000 can have an outer housing 4010 formed in two parts: an upper portion 4012 and a lower portion 4014. In addition, the outer housing 4010 can include one or more panels 4015. The RPT device 4000 can include a chassis 4016 that supports one or more internal components of the RPT device 4000. The RPT device 4000 can include a handle 4018.

[0389] The pneumatic path of the RPT device 4000 may include one or more air path items, such as an inlet air filter 4112, an inlet muffler 4122, a pressure generator 4100 capable of supplying air at a positive pressure (e.g., a blower 4142), an outlet muffler 4124, and one or more converters 4270, such as a pressure sensor 4272 and a flow sensor 4274.

[0390] One or more air path items may be located within a removable unitary structure, which will be referred to as a pneumatic block 4020. The pneumatic block 4020 may be located within the outer housing 4010. In one form, the pneumatic block 4020 is supported by or formed as part of the chassis 4016.

[0391] The RPT device 4000 may have a power supply 4210, one or more input devices 4220, a central controller, a therapy device controller 4240, a pressure generator 4100, one or more protection circuits 4250, a memory 4260, a converter 4270, a data communication interface 4280, and one or more output devices 4290. The electrical components 4200 may be mounted on a single printed circuit board assembly (PCBA) 4202. In an alternative form, the RPT device 4000 may include more than one PCBA 4202.

[0392] As described above, in some forms of the present technology, the central controller may be configured to implement one or more algorithms 4300 represented as computer programs stored in a non-transitory computer-readable storage medium, such as memory 4260. The algorithms 4300 are generally grouped into groups called modules.

[0393] An RPT device according to one form of the present technology may include an air filter 4110, or multiple air filters 4110.

[0394] In one form, an outlet air filter 4114 , such as an antimicrobial filter, is positioned between the outlet of the pneumatic block 4020 and the patient interface 3000 .

[0395] An RPT device according to one form of the present technology may include a silencer 4120 , or a plurality of silencers 4120 .

[0396] In one form of the present technology, an anti-spill back valve 4160 is positioned between the humidifier 5000 and the pneumatic block 4020. The anti-spill back valve is constructed and arranged to reduce the risk of water flowing upstream from the humidifier 5000 to the motor 4144, for example.

[0397] 5.4.1.1 Preprocessing Module

[0398] A pre-processing module 4310 in accordance with one form of the present technology receives as input a signal from a transducer 4270 (e.g., a flow sensor 4274 or a pressure sensor 4272) and performs one or more processing steps to calculate one or more output values ​​to be used as input to another module (e.g., a therapy engine module 4320).

[0399] In one form of the present technology, the output values ​​include interface or mask pressure Pm, respiratory flow Qr, and leak flow Ql.

[0400] In various forms of the present technology, the pre-processing module 4310 includes one or more of the following algorithms: pressure compensation 4312 , ventilation flow estimation 4314 , leak flow estimation 4316 , and respiratory flow estimation 4318 .

[0401] 5.4.1.1.1 Pressure compensation

[0402] In one form of the present technology, a pressure compensation algorithm 4312 receives as input a signal indicative of the pressure in the pneumatic path adjacent the outlet of the pneumatic block. The pressure compensation algorithm 4312 estimates the pressure drop across the air circuit 4170 and provides as output the estimated pressure Pm in the patient interface 3000.

[0403] 5.4.1.1.2 Ventilation Flow Estimation

[0404] In one form of the present technology, a ventilation flow estimation algorithm 4314 receives as input an estimated pressure Pm in the patient interface 3000 and estimates a ventilation flow Qv of air from the ventilation system 3400 in the patient interface 3000 .

[0405] 5.4.1.1.3 Leakage flow estimation

[0406] In one form of the present technology, a leak flow estimation algorithm 4316 receives as input the total flow Qt and the ventilation flow Qv and provides as output an estimate of the leak flow Ql. In one form, the leak flow estimation algorithm estimates the leak flow Ql by averaging the difference between the total flow Qt and the ventilation flow Qv over a sufficiently long period of time (e.g., approximately 10 seconds).

[0407] In one form, the leak flow estimation algorithm 4316 receives the total flow Qt, the ventilation flow Qv, and the estimated pressure Pm as inputs in the patient interface 3000 and provides the leak flow Ql as output by calculating the leak conductance and determining the leak flow Ql as a function of the leak conductance and the pressure Pm. The leak conductance is calculated as the quotient of the low-pass filtered non-ventilation flow, which is equal to the difference between the total flow Qt and the ventilation flow Qv, and the low-pass filtered pressure square root Pm, where the low-pass filter time constant has a value long enough to cover several respiratory cycles, for example, approximately 10 seconds. The leak flow Ql can be estimated as the product of the leak conductance and the function of the pressure Pm.

[0408] 5.4.1.1.4 Respiratory flow estimation

[0409] In one form of the present technology, a respiratory flow estimation algorithm 4318 receives as input the total flow Qt, ventilation flow Qv, and leak flow Ql and estimates the respiratory flow Qr of air to the patient by subtracting the ventilation flow Qv and leak flow Ql from the total flow Qt.

[0410] 5.4.1.2 Treatment Engine Module

[0411] In one form of the present technology, therapy engine module 4320 receives as input one or more of pressure Pm in patient interface 3000 and respiratory flow Qr of air to the patient, and provides as output one or more therapy parameters.

[0412] 5.4.1.3 Treatment Control Module

[0413] The therapy control module 4330 according to one aspect of the present technology receives as input therapy parameters from the therapy parameter determination algorithm 4329 of the therapy engine module 4320 and controls the pressure generator 4100 to deliver air flow according to the therapy parameters.

[0414] In one form of the present technology, the therapy parameter is a therapy pressure Pt, and the therapy control module 4330 controls the pressure generator 4100 to deliver an air flow at a mask pressure Pm at the patient interface 3000 equal to the therapy pressure Pt.

[0415] 5.5 Air circuit

[0416] The air circuit 4170 according to one aspect of the present technology is a conduit or tube that, when in use, is constructed and arranged to allow air flow to travel between two components, such as the RPT device 4000 and the patient interface 3000 .

[0417] Specifically, the air circuit 4170 can be fluidly connected to the outlet of the pneumatic block 4020 and the patient interface. The air circuit can be referred to as an air delivery tube. In some cases, there can be separate branches for the inspiratory and expiratory circuits. In other cases, a single branch is used.

[0418] In some forms, the air circuit 4170 may include one or more heating elements configured to heat the air in the air circuit, for example to maintain or increase the temperature of the air. The heating element may be in the form of a heating wire loop and may include one or more transducers, such as a temperature sensor. In one form, the heating wire loop may be helically wound around the axis of the air circuit 4170. The heating element may be in communication with a controller, such as a central controller 4230. An example of an air circuit 4170 including a heating wire loop is described in U.S. Patent 8,733,349, which is incorporated herein by reference in its entirety.

[0419] Figure 13 Various configurations are depicted for incorporating an exemplary ventilation system 3400 with various patient interfaces 3000A-C.

[0420] The first housing member 3430 of the ventilation housing 3402 can provide an interface for connecting the ventilation system 3400 to the air circuit connector 4171 to connect the ventilation system 3400 to the air circuit 4170 and position the ventilation system 3400 within the flow path. In this example, the inlet connection portion 3416 of the first housing member 3430 enables the ventilation housing 3402 to be fluidically connected to the air circuit 4170.

[0421] The second housing member 3440 of the vent housing 3402 can provide an interface for connecting the vent system 3400 to the vent connector tube 4180 at the tube connector 4182. The vent connector tube 4180 can be a short tube as is known in the art. In this example, the outlet connection portion 3420 of the second housing member 3440 is configured to fluidly connect the vent housing 3402 to the exhaust connector tube elbow 4181.

[0422] The ventilation connection tube 4180 can be connected to the nasal patient interface 3000A, which can be configured to seal at least the lower periphery of the patient's nose, or which can be configured to receive at least the tip of the patient's nose to seal around the nose, or to the nasal pillow patient interface 3000B, which can include pillows on a stem for sealing with each nostril, opposite the tube connector 4182 via a ventilation connection tube elbow 4181. The ventilation connector tube 4180 can be lighter and / or have a smaller diameter than the air circuit 4170 because such a configuration allows the ventilation system 3400 to be spaced apart from the patient interface 3000A / 3000B to reduce tube resistance. In the case of a full-face patient interface 3000C, which can be configured to seal the patient's face around the nose and mouth together so that gas is directed to the patient's nose and mouth through a single opening, or it can be configured as an ultra-compact full-face patient interface having one or two openings to direct gas to the patient's nostrils and another opening to direct gas to the patient's mouth, the ventilation connection tube 4180 can be excluded and the outer wall of the ventilation shell 3402 can be joined to the decoupling structure 3500.

[0423] In any of these configurations, a heat and moisture exchanger (HMX) (not shown) may also be included. For example, the HMX may be provided between the patient interface 3000 and the ventilation connector tube 4180 or between the tube connector 4182 and the ventilation system 3400. Alternatively, the HMX may be positioned within the plenum 3200. In any of these HMX configurations, the HMX may be positioned between the patient's airway and the ventilation system 3400 so that exhaled gases can deposit their heat and moisture onto the HMX material before being exhausted to the atmosphere.

[0424] 5.6 Humidifier

[0425] 5.6.1 Humidifier Overview

[0426] In one form of the present technology, a humidifier 5000 (e.g., Figure 5A ) to change the absolute humidity of the air or gas for delivery to the patient relative to the ambient air. Typically, the humidifier 5000 is used to increase the absolute humidity of the air flow and increase the temperature of the air flow (relative to the ambient air) before delivery to the patient's airway.

[0427] The humidifier 5000 may include a humidifier reservoir 5110, a humidifier inlet 5002 for receiving an air flow, and a humidifier outlet 5004 for delivering a humidified air flow. Figure 5A and Figure 5B As shown, the inlet and outlet of the humidifier reservoir 5110 can be respectively a humidifier inlet 5002 and a humidifier outlet 5004. The humidifier 5000 can also include a humidifier base 5006, which can be adapted to receive the humidifier reservoir 5110 and include a heating element 5240.

[0428] 5.6.2 Humidifier components

[0429] 5.6.2.1 Water reservoir

[0430] According to one arrangement, the humidifier 5000 may include a water reservoir 5110 configured to hold or retain a volume of liquid (e.g., water) to be evaporated for humidifying the air flow. The water reservoir 5110 may be configured to hold a predetermined maximum water volume to provide adequate humidification for at least the duration of a respiratory therapy session, such as one night of sleep. Typically, the reservoir 5110 is configured to hold several hundred milliliters of water, for example, 300 milliliters (ml), 325 ml, 350 ml, or 400 ml. In other forms, the humidifier 5000 may be configured to receive a water supply from an external water source, such as a building's water supply.

[0431] According to one aspect, water reservoir 5110 is configured to add humidity to the air flow from RPT device 4000 as the air flow travels therethrough. In one form, water reservoir 5110 may be configured to encourage the air flow to travel in a tortuous path through reservoir 5110 while in contact with the volume of water therein.

[0432] According to one form, the reservoir 5110 may be arranged, for example, along Figure 5A and Figure 5B Shown in a sideways orientation removed from the humidifier 5000.

[0433] The reservoir 5110 can also be configured to prevent liquid from flowing out of it, such as through any holes and / or between its subcomponents, such as when the reservoir 5110 is displaced and / or rotated from its normal operating orientation. Since the air flow to be humidified by the humidifier 5000 is generally pressurized, the reservoir 5110 can also be configured to avoid loss of pneumatic pressure through leakage and / or flow resistance.

[0434] 5.6.2.2 Conductive part

[0435] According to one arrangement, the reservoir 5110 includes a conductive portion 5120 configured to allow efficient transfer of heat from the heating element 5240 to the liquid volume in the reservoir 5110. In one form, the conductive portion 5120 can be configured as a plate, but other shapes are also suitable. All or a portion of the conductive portion 5120 can be made of a thermally conductive material, such as aluminum (e.g., having a thickness of approximately 2 mm, such as 1 mm, 1.5 mm, 2.5 mm, or 3 mm), another thermally conductive metal, or some plastics. In some cases, suitable thermal conductivity can be achieved using a material with a suitable geometry having a lower conductivity.

[0436] 5.6.2.3 Humidifier reservoir base

[0437] In one form, the humidifier 5000 may include a humidifier reservoir base 5130 (e.g., Figure 5B ), which is configured to receive the humidifier reservoir 5110. In some arrangements, the humidifier reservoir base 5130 may include a locking feature, such as a locking lever 5135 configured to retain the reservoir 5110 in the humidifier reservoir base 5130.

[0438] 5.6.2.4 Water level indicator

[0439] The humidifier reservoir 5110 may include Figures 5A-5B 10. In some forms, the water level indicator 5150 may provide a user (such as the patient 1000 or a caregiver) with one or more indications regarding the amount of water volume in the humidifier reservoir 5110. The one or more indications provided by the water level indicator 5150 may include an indication of a maximum predetermined volume of water, any fraction thereof, such as 25%, 50%, 75%, or a volume such as 200 ml, 300 ml, or 400 ml.

[0440] 5.7 Respiratory Waveform

[0441] Figure 6AThe following figure shows a typical respiratory waveform for a modeled human during sleep. The horizontal axis represents time, and the vertical axis represents respiratory flow. While parameter values ​​can vary, a typical breath can have the following approximate values: tidal volume Vt 0.5 L, inspiratory time Ti 1.6 s, peak inspiratory flow Qpeak 0.4 L / s, expiratory time Te 2.4 s, and peak expiratory flow Qpeak -0.5 L / s. The total duration of the breath, Ttot, is approximately 4 s. Humans typically breathe at a rate of approximately 15 breaths per minute (BPM) and a ventilation rate, Vent, of approximately 7.5 L / min. The typical duty cycle, the ratio of Ti to Ttot, is approximately 40%.

[0442] 5.8 Screening, Diagnosis, and Monitoring Systems

[0443] 5.8.1 Polysomnography

[0444] Figure 7A A patient 1000 undergoing a polysomnogram (PSG) is shown. The PSG system includes a headbox 2000 that receives and records signals from the following sensors: EOG electrodes 2015; EEG electrodes 2020; ECG electrodes 2025; submandibular EMG electrodes 2030; a snoring sensor 2035; a respiratory inductive plethysmogram (respiratory effort sensor) 2040 on a chest strap; a respiratory inductive plethysmogram (respiratory effort sensor) 2045 on an abdominal strap; an oral-nasal cannula with an oral thermistor 2050; a photoplethysmograph (pulse oximeter) 2055; and a body position sensor 2060. The electrical signals are referenced to a ground electrode (ISOG) 2010 located at the center of the forehead.

[0445] 5.8.2 Unobtrusive Monitoring Systems

[0446] Figure 7B An example of a monitoring device 7100 for monitoring the breathing of a sleeping patient 1000 is shown. The monitoring device 7100 includes a non-contact motion sensor generally directed toward the patient 1000. The motion sensor is configured to generate one or more signals representing body movements of the patient 1000, from which signals representing the patient's respiratory movements can be derived.

[0447] 5.9 Glossary

[0448] For purposes of this technical disclosure, in some forms of the technology, one or more of the following definitions may apply. In other forms of the technology, alternative definitions may apply.

[0449] 5.9.1 Overview

[0450] Air: In some forms of the present technology, air may be considered to mean atmospheric air, and in other forms of the present technology, air may be considered to mean some other combination of breathable gases, such as atmospheric air enriched with oxygen.

[0451] Environment: In certain forms of the present technology, the term environment can have the meaning of (i) external to the treatment system or patient, and (ii) immediately surrounding the treatment system or patient.

[0452] For example, the ambient humidity relative to the humidifier can be the humidity of the air directly surrounding the humidifier, such as the humidity inside the room that the patient is sleeping in. This ambient humidity can be different from the humidity outside the room that the patient is sleeping.

[0453] In another example, ambient pressure may be the pressure immediately surrounding or external to the body.

[0454] In some forms, ambient (e.g., acoustic) noise can be considered to be the background noise level in the room the patient is in, in addition to noise generated, for example, by the RPT device or emanating from a mask or patient interface. Ambient noise can be generated by sound sources outside the room.

[0455] Automatic Positive Airway Pressure (APAP) Therapy: CPAP therapy in which the therapy pressure is automatically adjusted between a minimum and a maximum limit, eg, breath-to-breath, depending on whether there is an indication of an SBD event.

[0456] Continuous Positive Airway Pressure (CPAP) Therapy: A respiratory pressure therapy in which the treatment pressure is approximately constant throughout a patient's breathing cycle. In some forms, the pressure at the airway entrance will be slightly higher during exhalation and slightly lower during inspiration. In some forms, the pressure will vary between different breathing cycles of a patient, for example, increasing in response to detecting an indication of partial upper airway obstruction and decreasing in the absence of an indication of partial upper airway obstruction.

[0457] Flow rate: The volume (or mass) of air delivered per unit time. Flow rate can refer to an instantaneous quantity. In some cases, reference to flow rate will be to a scalar quantity, i.e., a quantity having only magnitude. In other cases, reference to flow rate will be to a vector quantity, i.e., a quantity having both magnitude and direction. Flow rate can be given by the symbol Q. 'Flow rate' is sometimes simply abbreviated to 'flow' or 'air flow'.

[0458] In the example of a patient breathing, the flow rate can be nominally positive for the inspiratory portion of the patient's breathing cycle and thus negative for the expiratory portion of the patient's breathing cycle. The total flow rate, Qt, is the flow rate of air leaving the RPT device. The ventilation flow rate, Qv, is the flow rate of air leaving the vent to allow flushing of exhaled gas. The leakage flow rate, Ql, is the leakage flow from the patient interface system or elsewhere. The respiratory flow rate, Qr, is the flow rate of air received into the patient's breathing system.

[0459] Humidifier: The term humidifier will be deemed to refer to a humidifying device constructed and arranged or configured with a physical structure capable of providing therapeutically beneficial amounts of water (H2O) vapor to an air flow to improve a patient's medical respiratory condition.

[0460] Leakage: The word leakage is considered to be undesirable air flow. In one example, a leak may occur due to an incomplete seal between the mask and the patient's face. In another example, a leak may occur in the swivel elbow to the surrounding environment.

[0461] Noise, Conducted (Acoustic): Conducted noise in this document refers to the noise brought to the patient through the pneumatic path (such as the air circuit and patient interface and the air therein). In one form, conducted noise can be quantified by measuring the sound pressure level at the end of the air circuit.

[0462] Noise, radiated (acoustic): Radiated noise in this document refers to the noise that reaches the patient through the ambient air. In one form, radiated noise can be quantified by measuring the sound power / pressure level of the object in question according to ISO 3744.

[0463] Noise, Ventilation (Acoustics): Ventilation noise in this document refers to the noise generated by the flow of air through any vent, such as the vent of a patient interface.

[0464] Patient: A person, whether or not they have a respiratory condition.

[0465] Pressure: force per unit area. Pressure can be expressed in a range of units, including cmH2O, gf / cm 2 , hectopascal. 1cmH2O equals 1g-f / cm 2 And is about 0.98 hectopascal.In this specification, unless otherwise specified, pressure is given in cmH2O.

[0466] The pressure in the patient interface is given the symbol Pm, while the treatment pressure is given the symbol Pt, which represents the target value to be achieved by the mask pressure Pm at the current moment.

[0467] Respiratory Pressure Therapy (RPT): The application of a supply of air to the airway entrance at a therapeutic pressure that is typically positive relative to atmosphere.

[0468] Ventilator: A mechanical device that provides pressure support to a patient to perform some or all of the work of breathing.

[0469] 5.9.1.1 Materials

[0470] Silicone or Silicone Elastomer: A synthetic rubber. In this specification, references to silicone refer to liquid silicone rubber (LSR) or compression molded silicone rubber (CMSR). One form of commercially available LSR is SILASTIC (included in the range of products sold under this trademark), which is manufactured by Dow Corning. Another manufacturer of LSR is Wacker. Unless otherwise specified, exemplary forms of LSR have a Shore A (or Type A) indentation hardness in the range of about 35 to about 45 as measured using ASTM D2240.

[0471] Polycarbonate: is a thermoplastic polymer of bisphenol A carbonate.

[0472] 5.9.1.2 Mechanical properties

[0473] Resilience: The ability of a material to absorb energy during elastic deformation and release that energy when unloaded.

[0474] Elastic: Will release substantially all of its energy when unloaded. Includes, for example, certain silicones and thermoplastic elastomers.

[0475] Hardness: The ability of a material to resist deformation (as described, for example, by Young's modulus or the indentation hardness scale measured on a standardized sample size).

[0476] • "Soft" materials may include silicone or thermoplastic elastomers (TPEs) and may deform easily, for example under finger pressure.

[0477] • "Hard" materials may include polycarbonate, polypropylene, steel or aluminum, and may not deform easily, for example, under finger pressure.

[0478] Stiffness (or rigidity) of a structure or component: The ability of a structure or component to resist deformation in response to an applied load. The load can be a force or moment, such as compression, tension, bending, or torsion. The structure or component can provide different resistance in different directions.

[0479] Flexible structure or component: A structure or component that will change shape (eg, bend) when made to support its own weight for a relatively short period of time, eg, within 1 second.

[0480] Rigid structure or component: A structure or component that does not substantially change shape when subjected to loads typically encountered in use. An example of such use might be placing and maintaining a patient interface in sealing relationship with the entrance to a patient's airway, for example, under a load of pressure of approximately 20 to 30 cmH2O.

[0481] As an example, an I-beam may include a different bending stiffness (resistance to bending loads) in a first direction than in a second orthogonal direction.In another example, a structure or component may be flexible in a first direction and rigid in a second direction.

[0482] 5.9.2 Respiratory cycle

[0483] Apnea: According to some definitions, apnea is considered to occur when flow drops below a predetermined threshold for a sustained period of time (e.g., 10 seconds). Obstructive apnea is considered to occur when some obstruction of the airway does not allow air flow despite the patient's efforts. Central apnea is considered to occur when apnea is detected due to a decrease or absence of respiratory effort despite a patent airway. Mixed apnea is considered to occur when a decrease or absence of respiratory effort occurs simultaneously with an obstructed airway.

[0484] Respiratory rate: The rate at which a patient breathes spontaneously, usually measured in breaths per minute.

[0485] Duty cycle: the ratio of inspiratory time Ti to total breathing time Ttot.

[0486] Effort (breathing): The work done by a spontaneous breather in an attempt to breathe.

[0487] Expiratory portion of the respiratory cycle: the period from the start of expiratory flow to the start of inspiratory flow.

[0488] Flow Limitation: Flow limitation is considered a state in a patient's breathing in which an increase in patient effort does not result in a corresponding increase in flow. When flow limitation occurs during the inspiratory portion of the respiratory cycle, it may be described as inspiratory flow limitation. When flow limitation occurs during the expiratory portion of the respiratory cycle, it may be described as expiratory flow limitation.

[0489] Types of flow-limited inspiratory waveforms:

[0490] (i) Flat: has a rise, followed by a relatively flat section, followed by a fall.

[0491] (ii) M-shaped: having two local peaks, one at the leading edge and one at the trailing edge, and a relatively flat portion between the two peaks.

[0492] (iii) Chair shape: has a single local peak at the leading edge followed by a relatively flat section.

[0493] (iv) Inverted chair shape: has a relatively flat portion followed by a single local peak at the trailing edge.

[0494] Hypopnea: According to some definitions, hypopnea is considered a decrease in flow rather than a cessation of flow. In one form, hypopnea is considered to occur when flow decreases below a threshold rate for a sustained period of time. Central hypopnea is considered to occur when hypopnea is detected due to a decrease in respiratory effort. In one form in adults, any of the following may be considered hypopnea:

[0495] (i) The patient's respiration rate decreases by 30% for at least 10 seconds with an associated 4% desaturation;

[0496] (ii) The patient's breathing is reduced (but less than 50%) for at least 10 seconds, with an associated desaturation of at least 3% or arousal.

[0497] Hyperpnea: Increased air flow to a higher than normal level.

[0498] Inspiratory portion of the breathing cycle: The time period from the start of inspiratory flow to the start of expiratory flow is considered the inspiratory portion of the breathing cycle.

[0499] Patency (airway): The degree to which the airway is open or the degree to which the airway is open. An open airway is open. Airway patency can be quantified, for example with a value of (1) being open and a value of zero (0) being closed (obstructed).

[0500] Positive End-Expiratory Pressure (PEEP): The pressure above atmospheric pressure that exists in the lungs at the end of exhalation.

[0501] Peak flow (Qpeak): The maximum flow rate during the inspiratory portion of the respiratory flow waveform.

[0502] Respiratory flow, patient air flow, respiratory air flow (Qr): These terms may be understood to refer to the RPT device's estimate of respiratory flow, as opposed to "true respiratory flow" or "real respiratory flow," which is the actual respiratory flow experienced by the patient, typically expressed in liters per minute.

[0503] Tidal volume (Vt): The volume of air inhaled or exhaled during normal breathing when no additional effort is exerted. In principle, the inspiratory volume Vi (the volume of air inhaled) is equal to the expiratory volume Ve (the volume of air exhaled), so a single tidal volume Vt can be defined as equal to either volume. In practice, tidal volume Vt is estimated as some combination of inspiratory volume Vi and expiratory volume Ve, such as an average.

[0504] (Inhalation) Time (Ti): Duration of the inspiratory portion of the respiratory flow waveform.

[0505] (Expiratory) Time (Te): Duration of the expiratory portion of the respiratory flow waveform.

[0506] (Total) Time (Ttot): The total duration between the start of the inspiratory portion of one respiratory flow waveform and the start of the inspiratory portion of the subsequent respiratory flow waveform.

[0507] Typical recent ventilation: The ventilation value around which recent values ​​of ventilation Vent tend to cluster over some predetermined timeframe, ie a measure of the central tendency of recent ventilation values.

[0508] Upper airway obstruction (UAO): includes partial and total upper airway obstruction. This may be associated with a state of flow limitation, where flow increases only slightly, or even decreases, with increasing pressure differential across the upper airway (Starling impedance behavior).

[0509] Ventilation (Vent): A measurement of the rate of gas exchanged by a patient's respiratory system. Ventilation measurements can include either or both inspiratory and expiratory flow (per unit time). When expressed as volume per minute, this quantity is often referred to as "minute ventilation." Minute ventilation is sometimes given simply as volume and is understood to be the volume per minute.

[0510] 5.9.3 Anatomy

[0511] 5.9.3.1 Respiratory system anatomy

[0512] Diaphragm: A sheet of muscle that extends across the base of the rib cage. The diaphragm separates the thoracic cavity (which contains the heart, lungs, and ribs) from the abdominal cavity. As the diaphragm contracts, the volume of the thoracic cavity increases and air is drawn into the lungs.

[0513] Larynx: The larynx or voice box houses the vocal cords and connects the lower part of the pharynx (hypopharynx) to the trachea.

[0514] Lung: The respiratory organ of humans. The conducting zone of the lungs consists of the trachea, bronchi, bronchioles, and terminal bronchioles. The respiratory zone consists of the respiratory bronchioles, alveolar ducts, and alveoli.

[0515] Nasal Cavity: The nasal cavity (or nasal fossa) is a large, air-filled space in the middle of the face, above and behind the nose. The nasal cavity is divided into two parts by a vertical wing called the nasal septum. On the sides of the nasal cavity are three horizontal branches called the nasal conchae (singular "concha") or turbinates. The front of the nasal cavity is the nose, while the back connects to the nasopharynx via the internal nostrils.

[0516] Pharynx: The part of the throat located just below (underneath) the nasal cavity and above the esophagus and larynx. The pharynx is conventionally divided into three sections: the nasopharynx (epipharynx) (the nasal part of the pharynx), the oropharynx (mesopharynx) (the oral part of the pharynx), and the hypopharynx (hypopharynx).

[0517] 5.9.4 Patient Interface

[0518] Anti-Asphyxia Valve (AAV): A component or subcomponent of a mask system that reduces the risk of excessive CO2 rebreathing by the patient by opening to atmosphere in a fail-safe manner.

[0519] Elbow: An elbow is an example of a structure that directs the axis of air flow traveling therethrough to change direction through an angle. In one form, the angle may be approximately 90 degrees. In another form, the angle may be greater than or less than 90 degrees. The elbow may have a cross-section that is approximately circular. In another form, the elbow may have an oval or rectangular cross-section. In some forms, the elbow may be rotatable relative to the mating component, for example, approximately 360 degrees. In some forms, the elbow may be removable from the mating component, for example, via a snap connection. In some forms, the elbow may be assembled to the mating component via a one-time snap connection during manufacturing, but may not be removed by the patient.

[0520] Frame: A frame will be considered to mean the mask structure that carries the tensile load between two or more connection points to the headgear. A mask frame can be a non-airtight, load-bearing structure in the mask. However, some forms of mask frames can also be airtight.

[0521] Headgear: Headgear will be considered to mean a form of positioning and stabilizing structure designed to be placed on the head. For example, headgear may include a collection of one or more support rods, straps, and reinforcements configured to position and maintain the patient interface in position on the patient's face for delivery of respiratory therapy. Some straps are formed from soft, flexible, resilient materials, such as laminated composites of foam and fabric.

[0522] Film: A film shall be taken to mean a typically thin element which preferably has substantially no resistance to bending, but has resistance to stretching.

[0523] Plenum: A mask plenum will be taken to mean a portion of the patient interface having walls at least partially enclosing a volume of space which, in use, has air pressurized therein to above atmospheric pressure. The housing may form part of a wall of the mask plenum.

[0524] Seal: can be a noun referring to a structure (seal) or a verb referring to that effect (seal). Two elements can be constructed and / or arranged to 'seal' or achieve a 'seal' between them without the need for a separate 'seal' element itself.

[0525] Shell: Shell will be understood to mean a curved, relatively thin structure with bendable, stretchable, and compressible stiffness. For example, the curved structural wall of a mask can be the shell. In some forms, the shell can be multi-faceted. In some forms, the shell can be airtight. In some forms, the shell may not be airtight.

[0526] Reinforcement: A reinforcement will be taken to mean a structural component designed to increase the bending resistance of another component in at least one direction.

[0527] Support rod: A support rod will be considered a structural component designed to increase the compression resistance of another component in at least one direction.

[0528] Swivel (noun): A subassembly of components configured to rotate about a common axis, preferably independently, preferably under low torque. In one form, the swivel can be configured to rotate through an angle of at least 360 degrees. In another form, the swivel can be configured to rotate through an angle of less than 360 degrees. When used in the context of an air delivery conduit, the subassembly of components preferably comprises a pair of matching cylindrical conduits. There can be little or no air flow leakage from the swivel during use.

[0529] Lacera (noun): A structure used to resist tension.

[0530] Vent: (noun): A structure that allows air flow from the interior of a mask or conduit to ambient air for clinically effective flushing of exhaled gases. For example, clinically effective flushing may involve a flow rate of about 10 liters per minute to about 100 liters per minute, depending on the mask design and the therapy pressure.

[0531] 5.10 Other Comments

[0532] A portion of the disclosure of this patent document contains material which is subject to copyright protection. The copyright owner has no objection to the facsimile reproduction by anyone of the patent document or the patent disclosure, as it appears in the Patent Office file or records, but otherwise reserves all copyright rights whatsoever.

[0533] Unless the context clearly indicates otherwise and a numerical range is provided, it is understood that each intervening value between the upper and lower limits of that range, to the tenth of the unit of the lower limit, and any other stated or intervening value in that stated range are broadly encompassed within the present technology. The upper and lower limits of these intermediate ranges (which may independently be included in the intermediate ranges) are also encompassed within the present technology, subject to any specifically excluded limits in the stated ranges. Where the stated range includes one or both limits, ranges excluding either or both of those included limits are also encompassed within the present technology.

[0534] Furthermore, where one or more values ​​are stated herein as being implemented as part of a technology, it is understood that such values ​​may be approximate unless otherwise stated, and that such values ​​may be used with any suitable significant figures to the extent that actual technology implementation may allow or require it.

[0535] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this technology belongs. Although any methods and materials similar or equivalent to those described herein can also be used in the practice or testing of this technology, a limited number of exemplary methods and materials are described herein.

[0536] When a particular material is provided for use in constructing a component, obvious alternative materials having similar properties may be used as substitutes. Furthermore, unless specified to the contrary, any and all components described herein should be understood to be capable of being manufactured, and thus may be manufactured together or separately.

[0537] It must be noted that as used herein and in the appended claims, the singular forms "a," "an," and "the" include their plural equivalents unless the context clearly dictates otherwise.

[0538] All publications mentioned herein are incorporated herein by reference in their entirety to disclose and describe the methods and / or materials that are the subject of those publications. The publications discussed herein are provided solely for their disclosures prior to the filing date of the present application. This paper should not be construed as admitting that the present technology is not entitled to disclose earlier than this type of disclosure due to prior invention. In addition, the publication date provided may be different from the actual publication date, which may require independent confirmation.

[0539] The terms "comprises" and "comprising" should be understood to refer to elements, components or steps in a non-exclusive manner, indicating that the marked elements, components or steps may be present or utilized, or in combination with other elements, components or steps that are not marked.

[0540] The subject headings used in the detailed description are included only for the convenience of the reader and should not be used to limit the subject matter found in the entire disclosure or claims. The subject headings should not be used to interpret the scope of the claims or claim limitations.

[0541] Although the technology herein has been described with reference to specific examples, it should be understood that these examples only illustrate the principles and applications of the technology. In some cases, the terms and symbols may imply specific details that are not required to practice the technology. For example, although the terms "first" and "second" may be used, unless otherwise specified, they are not intended to represent any order, but may be used to distinguish different elements. In addition, although the process steps in the method can be described or shown in sequence, such order is not required. Those skilled in the art will recognize that such order can be modified and / or aspects thereof can be performed simultaneously or even synchronously.

[0542] It is therefore to be understood that numerous modifications may be made to the illustrative examples and that other arrangements may be devised without departing from the spirit and scope of the present technology.

[0543] 5.11 Reference Symbols

[0544] 1000 patients

[0545] 1100 Bed Partner

[0546] 3000 Patient Interface

[0547] 3100 Seal forming structure

[0548] 3200 Inflatable Chamber

[0549] 3300 Positioning and stabilizing structures

[0550] 3400 Ventilation System

[0551] 3402 Vent Housing

[0552] 3404 First end of the vent housing

[0553] 3405 Second end of vent housing

[0554] 3406 Longitudinal axis of the vent housing

[0555] 3407 Entrance

[0556] 3408 Export

[0557] 3416 Inlet connection part

[0558] 3418 Bayonet Accessories

[0559] 3420 outlet connection part

[0560] 3422 Internal Passage

[0561] 3424 Surface facing the membrane

[0562] 3425 Limiter Section

[0563] 3430 first shell component

[0564] 3431 First end of the first housing member

[0565] 3432 Second end of the first housing member

[0566] 3433 circular surface

[0567] 3434 Axis

[0568] 3435 flange

[0569] 3436 flange protrusion

[0570] 3437 Diffuser retaining edge

[0571] 3438 Second shell component connection portion

[0572] 3440 Second shell component

[0573] 3441 First end of the second housing member

[0574] 3442 second end of the second housing member

[0575] 3444 protrusion

[0576] 3446 Membrane stop flange

[0577] 3448 Diffuser retaining part

[0578] 3450 membrane

[0579] 3451 First end of membrane

[0580] 3452 Second end of membrane

[0581] 3454 Longitudinal axis of membrane

[0582] 3456 movable part of membrane

[0583] 3460 membrane support

[0584] 3462 connection part

[0585] 3464 Membrane support flange

[0586] 3465 baffle part

[0587] 3466 First end of baffle portion

[0588] 3467 Second end of baffle portion

[0589] 3468 Baffle flange

[0590] 3470 Exhaust Orifice Components

[0591] 3471 Diffused Exhaust Holes

[0592] 3472 Undiffused Exhaust Vent

[0593] 3473 Common exhaust port

[0594] 3474 Diffuser components

[0595] 3475 Intermediate exhaust flow orifice

[0596] 3476 exhaust orifice member first end

[0597] 3477 Second end of exhaust orifice member

[0598] 3478 middle exhaust port

[0599] 3600 port

[0600] 3700 Forehead Support

[0601] 4000 RPT device

[0602] 4010 External housing

[0603] 4012 upper part

[0604] 4014 lower part

[0605] 4015 Panel

[0606] 4016 chassis

[0607] 4018 handle

[0608] 4020 Pneumatic Block

[0609] 4100 Pressure Generator

[0610] 4110 Air Filter

[0611] 4112 Inlet air filter

[0612] 4114 Outlet Air Filter

[0613] 4120 Muffler

[0614] 4122 Inlet silencer

[0615] 4124 outlet silencer

[0616] 4142 Blower

[0617] 4144 Electric Motor

[0618] 4160 Anti-overflow Valve

[0619] 4170 Air Circuit

[0620] 4171 Air Circuit Connector

[0621] 4180 Vent Connector Tube

[0622] 4181 Ventilation Connector Tube Elbow

[0623] 4182 pipe connector

[0624] 4200 Electrical components

[0625] 4202 Printed Circuit Board Assembly (PCBA)

[0626] 4210 Power Supply

[0627] 4220 Input Device

[0628] 4240 Therapy Device Controller

[0629] 4250 Protection Circuit

[0630] 4260 Memory

[0631] 4270 Transducer

[0632] 4272 Pressure Sensor

[0633] 4274 Flow Sensor

[0634] 4280 Data Communication Interface

[0635] 4290 Output Device

[0636] 4300 Algorithm

[0637] 4310 Preprocessing Module

[0638] 4312 Pressure Compensation

[0639] 4314 Ventilation Flow Estimation

[0640] 4316 Leakage Flow Estimation

[0641] 4318 Respiratory Flow Estimation

[0642] 4320 Healing Engine Module

[0643] 4330 Treatment Control Module

[0644] 4329 Treatment Parameter Determination Algorithm

[0645] 5000 Humidifier

[0646] 5002 Humidifier inlet

[0647] 5004 Humidifier outlet

[0648] 5006 Humidifier Base

[0649] 5110 Humidifier Reservoir

[0650] 5120 Conductive part

[0651] 5130 Humidifier Reservoir Base

[0652] 5135 Locking lever

[0653] 5150 Water Level Indicator

[0654] 5240 Heating Element

[0655] 6000 pressurized volume

[0656] 6002 Exhaust flow channel

[0657] 6004 Exhaust flow channel inlet

[0658] 6006 Restriction Department

[0659] 6040 Trapped Air Cavity

[0660] 6050 Damping Chamber

[0661] 6051 First end of the damping chamber

[0662] 6052 Second end of the damping chamber

[0663] 6055 Damping Orifice

[0664] 6100 Atmosphere

[0665] 6201 Airflow from RPT device

[0666] 6202 Therapeutic Airflow

[0667] 6203 Ventilation Airflow

[0668] 6204 Diffused ventilation airflow

[0669] 6205 Undiffused ventilation airflow

[0670] 6206Damper chamber airflow.

Claims

1. A patient interface, comprising a plenum chamber that at least partially forms a volume that is pressurizable to a therapeutic pressure of at least 6 cmH2O above ambient air pressure throughout a patient's breathing cycle in use, the plenum chamber including a plenum chamber inlet port sized and configured to receive a therapeutic gas flow for breathing by the patient; a seal-forming structure constructed and arranged to seal with an area of ​​a patient's face surrounding an entrance to the patient's airway, said seal-forming structure having an aperture therein such that, during use, a therapeutic gas flow is delivered to at least an entrance to a nares of the patient, said seal-forming structure constructed and arranged, in use, to maintain said therapeutic pressure in the plenum during a breathing cycle of the patient; a positioning and stabilizing structure configured to maintain the seal-forming structure in a therapeutically effective position on the patient's head, A ventilation structure configured to discharge a ventilation gas flow to the atmosphere continuously throughout a patient's breathing cycle, the ventilation structure comprising: a ventilation housing comprising an inlet configured for receiving a flow of gas from a respiratory pressure therapy device, an outlet configured for supplying the therapeutic flow of gas to the plenum chamber inlet port, and at least one exhaust orifice configured for exhausting the ventilation flow of gas to atmosphere, the at least one exhaust orifice being sized and shaped for maintaining a therapeutic pressure in the plenum chamber in use; and a membrane positioned within the vent housing, the membrane having a first end and a second end spaced apart along a longitudinal axis of the membrane, the membrane having a movable portion positioned between the first end of the membrane and the second end of the membrane and about the longitudinal axis; wherein the movable portion of the membrane is radially spaced from a membrane-facing surface of an interior of the vent housing relative to the longitudinal axis of the membrane to form an exhaust flow channel between the movable portion of the membrane and the membrane-facing surface, the exhaust flow channel being configured to allow gas to flow from the volume through the exhaust flow channel to the atmosphere via the at least one exhaust aperture during use, wherein the movable portion of the membrane is elastically deformable and is configured to move radially relative to the membrane-facing surface in response to a pressure differential between an inner side of the membrane and an outer side of the membrane to change the cross-sectional area of ​​the exhaust flow channel and regulate ventilation airflow over a therapeutic pressure range; and Wherein the patient interface is configured to allow the patient to breathe from the ambient environment through their mouth in the absence of a flow of pressurized air through the plenum inlet port, or the patient interface is configured such that the patient's mouth is uncovered.

2. A patient interface according to claim 1, wherein the movable portion of the membrane is substantially cylindrical or frustoconical.

3. A patient interface according to claim 1 or 2, wherein the ventilation housing comprises a first end and a second end aligned along a longitudinal axis of the ventilation housing, the longitudinal axis of the membrane being aligned with the longitudinal axis of the ventilation housing.

4. A patient interface according to claim 3, wherein the movable portion of the membrane includes one or more walls that are aligned parallel to air flow through the ventilation housing from the first end of the ventilation housing to the second end of the ventilation housing.

5. A patient interface according to claim 3 or 4, wherein the ventilation housing comprises a first housing member at a first end of the ventilation housing and a second housing member at a second end of the ventilation housing, the first housing member and the second housing member being configured to be connected together.

6. A patient interface according to claim 5, wherein the first housing member includes an inlet connection portion configured to fluidly connect the vent structure to a supply conduit.

7. A patient interface comprising a plenum chamber that at least partially forms a volume that is pressurizable to a therapeutic pressure of at least 6 cmH2O above ambient air pressure throughout a patient's breathing cycle in use, the plenum chamber including a plenum chamber inlet port sized and configured to receive a therapeutic gas flow for breathing by the patient; a seal-forming structure constructed and arranged to seal with an area of ​​a patient's face surrounding an entrance to the patient's airway, said seal-forming structure having an aperture therein such that, during use, a therapeutic gas flow is delivered to at least an entrance to a nares of the patient, said seal-forming structure constructed and arranged, in use, to maintain said therapeutic pressure in the plenum during a breathing cycle of the patient; a positioning and stabilizing structure configured to maintain the seal-forming structure in a therapeutically effective position on the patient's head, A ventilation structure configured to discharge a ventilation gas flow to the atmosphere continuously throughout a patient's breathing cycle, the ventilation structure comprising: a ventilation housing comprising at least one exhaust aperture configured for exhausting gas to atmosphere, the at least one exhaust aperture being sized and shaped for maintaining a therapeutic pressure in the plenum chamber in use; and a membrane positioned within the vent housing, the membrane having a movable portion spaced from a membrane-facing surface within the vent housing to form an exhaust flow channel between the movable portion of the membrane and the membrane-facing surface, the exhaust flow channel being configured to allow gas to flow from the volume to the atmosphere via the at least one exhaust aperture, a damping structure configured to damp vibrations of the movable portion of the membrane, the damping structure comprising a damping chamber within the vent housing; wherein the movable portion of the membrane is elastically deformable and is configured to move relative to the membrane-facing surface in response to a pressure differential between a first side of the membrane and a second side of the membrane to change the cross-sectional area of ​​the exhaust flow channel and regulate ventilation airflow throughout a therapeutic pressure range; wherein the first side of the movable part of the membrane faces the membrane-facing surface and the second side of the movable part of the membrane at least partially forms the damping chamber; and Wherein the patient interface is configured to allow the patient to breathe from the ambient environment through their mouth in the absence of a flow of pressurized air through the plenum inlet port, or the patient interface is configured such that the patient's mouth is uncovered.

8. A patient interface comprising a plenum chamber that at least partially forms a volume that is pressurizable to a therapeutic pressure of at least 6 cmH2O above ambient air pressure throughout a patient's breathing cycle in use, the plenum chamber including a plenum chamber inlet port sized and configured to receive a therapeutic gas flow for breathing by the patient; a seal-forming structure constructed and arranged to seal with an area of ​​a patient's face surrounding an entrance to the patient's airway, said seal-forming structure having an aperture therein such that, during use, a therapeutic gas flow is delivered to at least an entrance to a nares of the patient, said seal-forming structure constructed and arranged, in use, to maintain said therapeutic pressure in the plenum during a breathing cycle of the patient; a positioning and stabilizing structure configured to maintain the seal-forming structure in a therapeutically effective position on the patient's head, A ventilation structure configured to discharge a ventilation gas flow to the atmosphere continuously throughout a patient's breathing cycle, the ventilation structure comprising: a vent housing comprising at least one exhaust aperture configured for exhausting gas from the volume to atmosphere, the at least one exhaust aperture being sized and shaped for maintaining a therapeutic pressure in the plenum chamber in use; a membrane positioned within the vent housing, the membrane having a movable portion, the movable portion having a first side and a second side; a entrapped air cavity positioned within the vent housing on the first side of the movable portion of the membrane, the movable portion of the membrane at least partially forming the entrapped air cavity; wherein the movable portion of the membrane is spaced apart from a membrane-facing surface of the interior of the vent housing to form an exhaust flow channel on the second side of the membrane between the movable portion of the membrane and the membrane-facing surface, the exhaust flow channel being configured to allow gas to flow from the volume through the exhaust flow channel to the atmosphere via the at least one exhaust aperture during use, wherein the movable portion of the membrane is elastically deformable and is configured to move relative to the membrane-facing surface in response to a pressure differential between a first side of the membrane and a second side of the membrane to change the cross-sectional area of ​​the exhaust flow channel and regulate ventilation airflow throughout a therapeutic pressure range; and Wherein the patient interface is configured to allow the patient to breathe from the ambient environment through their mouth in the absence of a flow of pressurized air through the plenum inlet port, or the patient interface is configured such that the patient's mouth is uncovered.

9. A patient interface comprising a plenum chamber that at least partially forms a volume that is pressurizable to a therapeutic pressure of at least 6 cmH2O above ambient air pressure throughout a patient's breathing cycle in use, the plenum chamber including a plenum chamber inlet port sized and configured to receive a therapeutic gas flow for breathing by the patient; a seal-forming structure constructed and arranged to seal with an area of ​​a patient's face surrounding an entrance to the patient's airway, said seal-forming structure having an aperture therein such that, during use, a therapeutic gas flow is delivered to at least an entrance to a nares of the patient, said seal-forming structure constructed and arranged, in use, to maintain said therapeutic pressure in the plenum during a breathing cycle of the patient; a positioning and stabilizing structure configured to maintain the seal-forming structure in a therapeutically effective position on the patient's head, A ventilation structure configured to discharge a ventilation gas flow to the atmosphere continuously throughout a patient's breathing cycle, the ventilation structure comprising: a vent housing comprising at least one vent aperture configured for venting gas from the pressurized volume to atmosphere, the at least one vent aperture being sized and shaped for maintaining a therapeutic pressure in the plenum chamber in use; a membrane positioned within the vent housing, the membrane having a first end and a second end spaced apart along a longitudinal axis of the membrane, the membrane having a movable portion positioned between the first end of the membrane and the second end of the membrane and about the longitudinal axis; wherein the movable portion of the membrane comprises a first side and a second side and is radially spaced from a membrane-facing surface of an interior of the vent housing relative to the longitudinal axis of the membrane to form an exhaust flow channel between the movable portion of the membrane and the membrane-facing surface on the second side of the membrane, the exhaust flow channel being configured for allowing gas to flow from the volume through the exhaust flow channel to the atmosphere via the at least one exhaust aperture during use; wherein the exhaust flow channel includes a region between the movable portion of the membrane and the membrane-facing surface, the region having a smaller cross-sectional area than an adjacent region of the exhaust flow channel, and wherein the movable portion of the membrane is elastically deformable and is configured to move radially relative to the membrane-facing surface in response to a pressure differential between the first side of the membrane and the second side of the membrane to change the cross-sectional area of ​​the exhaust flow channel and adjust ventilation airflow throughout the therapeutic pressure range; and Wherein the patient interface is configured to allow the patient to breathe from the ambient environment through their mouth in the absence of a flow of pressurized air through the plenum inlet port, or the patient interface is configured such that the patient's mouth is uncovered.

10. A patient interface comprising a plenum chamber that at least partially forms a volume that is pressurizable to a therapeutic pressure of at least 6 cmH2O above ambient air pressure throughout a patient's breathing cycle in use, the plenum chamber comprising a plenum chamber inlet port sized and configured to receive a therapeutic gas flow for breathing by the patient from the pressurized volume; a seal-forming structure constructed and arranged to seal with an area of ​​a patient's face surrounding an entrance to the patient's airway, said seal-forming structure having an aperture therein such that, during use, a therapeutic gas flow is delivered to at least an entrance to a nares of the patient, said seal-forming structure constructed and arranged, in use, to maintain said therapeutic pressure in the plenum during a breathing cycle of the patient; a positioning and stabilizing structure configured to maintain the seal-forming structure in a therapeutically effective position on the patient's head, A ventilation structure configured to discharge a ventilation gas flow to the atmosphere continuously throughout a patient's breathing cycle, the ventilation structure comprising: a vent housing comprising at least one exhaust aperture configured for exhausting gas from the volume to atmosphere, the at least one exhaust aperture being sized and shaped for maintaining a therapeutic pressure in the plenum chamber in use; a membrane positioned within the vent housing, the membrane having a first end and a second end spaced apart along a longitudinal axis of the membrane, the membrane having a movable portion positioned between the first end of the membrane and the second end of the membrane and about the longitudinal axis; wherein the movable portion of the membrane is spaced radially inwardly relative to the longitudinal axis of the membrane from a membrane-facing surface of an interior of the vent housing to form an exhaust flow channel between the movable portion of the membrane and the membrane-facing surface, the exhaust flow channel being configured to allow gas to flow from the volume through the exhaust flow channel to the atmosphere via the at least one exhaust aperture during use, and wherein the movable portion of the membrane is elastically deformable and is configured to move radially relative to the membrane-facing surface in response to a pressure differential between an inner side of the membrane and an outer side of the membrane to change the cross-sectional area of ​​the exhaust flow channel and regulate ventilation airflow over a therapeutic pressure range; and Wherein the patient interface is configured to allow the patient to breathe from the ambient environment through their mouth in the absence of a flow of pressurized air through the plenum inlet port, or the patient interface is configured such that the patient's mouth is uncovered.

Images