Humidifier reservoir

Abstract

A water reservoir for a device for humidifying a flow of breathable gas, comprising a reservoir base comprising a cavity configured to hold a volume of liquid; and an electrically conductive portion disposed on the base. The electrically conductive portion is adapted to be in thermal engagement with a heater plate to allow heat to be transferred from the heater plate to the volume of liquid. The electrically conductive portion comprises a film comprising a non-metallic material, the film having a wall thickness of less than about 1 mm.

Description

[0001] This application is a divisional application of patent application number 201780072867.X, filed on 21 November 2017, entitled "Humidifier Reservoir". The application number 201780072867.X is the Chinese national phase of PCT International Application PCT / AU2017 / 051276.

[0002] 1 CROSS REFERENCE TO RELATED APPLICATIONS

[0003] This application claims the benefit of Australian provisional application number 2016904769, filed on 22 November 2016, the entire contents of which are incorporated herein by reference. 2 BACKGROUND 2.1 TECHNICAL FIELD

[0006] The present technology relates to one or more of the detection, diagnosis, treatment, prevention and amelioration of respiratory-related disorders. The present technology also relates to medical devices or apparatuses, and their use.

[0007] 2.2 DESCRIPTION OF RELATED ART

[0008] 2.2.1 The Human Respiratory System and Its Disorders

[0009] The respiratory system of the body facilitates gas exchange. The nose and mouth form entry points to the airways.

[0010] The airways include a sequence of branching air tubes, which become narrower, shorter and more numerous as they penetrate more deeply into the lung. The main function of the lungs is gas exchange, allowing oxygen to move from inhaled air into the venous blood and carbon dioxide from the venous blood into exhaled air. The trachea divides to form the right and left bronchial tubes, which in turn divide further to form the bronchioles. The bronchi constitute the conducting airways but do not participate in gas exchange. Other branches of the airways lead to the respiratory bronchioles, and ultimately to the pulmonary alveoli, where gas exchange occurs. The pulmonary alveoli region of the lungs is where gas exchange takes place, and is known as the respiratory zone. See West, John B. Respiratory Physiology—The Essentials, 9th Ed., Lippincott Williams & Wilkins, 2012.

[0011] A number of respiratory disorders exist. Certain disorders can be characterised by particular events, such as apnoeas, hypopnoeas, and hyperpnoeas.

[0012] Examples of respiratory disorders include obstructive sleep apnoea (OSA), Cheyne-Stokes Respiration (CSR), respiratory insufficiency, Obesity Hypoventilation Syndrome (OHS), Chronic Obstructive Pulmonary Disease (COPD), Neuromuscular Disease (NMD), and Chest Wall Disorders.

[0013] Obstructive sleep apnea (OSA) is a form of sleep-disordered breathing (SDB) characterized by events involving closure or obstruction of the upper airway during sleep. It arises from a combination of abnormally small upper airway size and normal loss of muscle tone in the areas of the tongue, soft palate, and posterior oropharyngeal walls during sleep. This condition causes the affected patient 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 result in cardiovascular disease and brain damage. Concomitant symptoms are common, especially in middle-aged overweight men, but those affected may not be aware of the problem. See U.S. Patent No. 4,944,310 (Sullivan).

[0014] Cheyne-Stokes respiration (CSR) is another form of sleep-disordered breathing. CSR is a disorder of the patient's respiratory controller, characterized by rhythmic alternations of waxing and waning ventilation known as CSR cycles. CSR is characterized by repetitive hypoxia and reoxygenation of arterial blood. Because of the repetitive oxygen deprivation, CSR can be harmful. In some patients, CSR is associated with repetitive microarousing from sleep, leading to severe sleep disruption, increased sympathetic activity, and increased afterload. See U.S. Patent No. 6,532,959 (Berthon-Jones).

[0015] Respiratory failure is a broad term encompassing respiratory disorders in which the lungs are unable to inhale enough oxygen or exhale enough CO2 to meet the patient's needs. Respiratory failure may include some or all of the following disorders.

[0016] Patients with respiratory insufficiency (a form of respiratory failure) may experience abnormal shortness of breath during exercise.

[0017] Obesity hyperventilation syndrome (OHS) is defined as a combination of severe obesity and chronic hypercapnia at wakefulness, without any other known cause of hypoventilation. Symptoms include dyspnea, morning headache, and excessive daytime sleepiness.

[0018] Chronic Obstructive Pulmonary Disease (COPD) encompasses any of a group of lower airway diseases that have certain characteristics in common. These include increased resistance to air movement, prolonged expiratory phase, and loss of the normal elasticity of the lung. Examples of COPD are emphysema and chronic bronchitis. COPD is caused by chronic tobacco smoking (the single most important risk factor), occupational exposures, air pollution, and genetic factors. Symptoms include: dyspnea on exertion, chronic cough, and sputum production.

[0019] Neuromuscular Disease (NMD) is a broad term that encompasses many diseases and disorders that impair the functioning of the muscles either directly, such as with muscular dystrophy, or indirectly, such as with neuromuscular conditions including multiple sclerosis. Some NMD patients are characterised by progressive muscular impairment leading to loss of ambulation, being wheelchair-bound, swallowing difficulties, respiratory muscle weakness, and eventually death from respiratory failure. Neuromuscular disorders can be divided into rapidly progressive and slowly progressive: (i) Rapidly progressive disorders: Characterised by muscle impairment that progresses over months and results in death within a few years (e.g. Amyotrophic lateral sclerosis (ALS) and Duchenne muscular dystrophy (DMD) in teenagers). (ii) Variable or slowly progressive disorders: Characterised by muscle impairment that progresses over years and only modestly shortens life expectancy (e.g. Limb girdle syndrome, Facioscapulohumeral syndrome and Myotonic syndrome). Symptoms of respiratory failure in NMD include: increasing generalised weakness, dysphagia, dyspnea on exertion and at rest, fatigue, sleepiness, morning headache, and difficulties with concentration and mood changes.

[0020] Chest wall disorders are a group of thoracic deformities that result in inefficient coupling of the respiratory muscles to the thoracic cage. The disorders are usually characterised by a restrictive defect and share the potential of long term hypercapnic respiratory failure. Scoliosis and / or kyphoscoliosis can cause severe respiratory failure. Symptoms of respiratory failure include: dyspnea on exertion and at rest, peripheral oedema, orthopnea, repeated chest infections, morning headache, fatigue, poor sleep quality, and poor concentration.

[0021] A range of therapies have been used to treat or alleviate such conditions. In addition, these therapies can be utilised on otherwise healthy individuals in order to prevent respiratory disorders from occurring. However, these therapies have a number of disadvantages.

[0022] 2.2.2 Treatment

[0023] Various therapies have been used to treat one or more of the above respiratory disorders, such as Continuous Positive Airway Pressure (CPAP), Non-invasive ventilation (NIV) and Invasive ventilation (IV).

[0024] Continuous Positive Airway Pressure (CPAP) therapy has been used to treat Obstructive Sleep Apnea (OSA). The mechanism of action is that continuous positive airway pressure acts as a pneumatic splint and can prevent upper airway occlusion by pushing the soft palate and tongue forward and away from the posterior oropharyngeal wall. Treatment of OSA by CPAP therapy can be voluntary, and as such, patients can elect not to comply with therapy if they find the devices used to provide such therapy: uncomfortable, difficult to use, expensive and unattractive for any one or more of a number of reasons.

[0025] Non-invasive ventilation (NIV) provides ventilatory support to a patient through the upper airways. NIV can help patients breathe and / or maintain adequate oxygen levels in the body by doing some or all of the work of breathing. The ventilatory support is provided via a non-invasive patient interface. NIV has been used to treat CSR and respiratory failure, which comes in forms such as OHS, COPD, NMD and Chest Wall disorders. In some forms, the comfort and effectiveness of these therapies can be improved.

[0026] Invasive ventilation (IV) provides ventilatory support to a patient who is unable to breathe effectively on their own, and can be provided using an tracheostomy tube. In some forms, the comfort and effectiveness of these therapies can be improved.

[0027] 2.2.3 Therapy Systems

[0028] These therapies can be provided by a therapy system or device. Such systems and devices can also be used to diagnose a disorder without treating the disorder.

[0029] A therapy system can include a respiratory pressure therapy device (RPT device), an air circuit, a humidifier, a patient interface, and data management.

[0030] Another form of therapy system is a mandibular repositioning device.

[0031] 2.2.3.1 Patient Interface

[0032] A patient interface can be used to interface a respiratory treatment device to its wearer, such as by providing a flow of air to the entrance of the airways. The flow of air can be provided via a mask to the nose and / or mouth of a patient, via a tube to the mouth, or via a tracheal tube to the trachea of a patient. Depending on the treatment to be applied, the patient interface can form a seal with the region of the patient's face, such as the nose and mouth, to facilitate the delivery of gas pressure at a sufficient difference to ambient pressure to effect therapy, e.g. positive pressure of about 10 cmH20 relative to ambient pressure. For other forms of therapy, e.g. oxygen supplementation, the patient interface can not include a seal sufficient to deliver gas pressure about 10 cmH20 to the airways.

[0033] Certain other mask systems can not be functionally suitable for the art. For example, masks that are purely decorative can not be able to maintain a suitable pressure. Masks for use in underwater swimming or diving can be constructed to prevent water from flowing in from the outside at high pressure, rather than to maintain air at a higher pressure than ambient inside.

[0034] Certain masks can be clinically disadvantageous to the art, for example they block airflow via the nose and only allow it past the mouth.

[0035] Certain masks can be uncomfortable or unachievable for the art if they require the patient to insert a portion of the mask structure into their mouth to form and maintain a seal past their lips.

[0036] Certain masks can be unachievable for use while sleeping, for example while lying on one's side in bed with one's head on a pillow.

[0037] The design of patient interfaces presents several challenges. The face has a complex three-dimensional shape. The size and shape of the nose and head varies significantly from person to person. As the head includes bone, cartilage, and soft tissue, different regions of the face react differently to mechanical forces. The mandible, or lower jaw, can move relative to other bones of the skull. The entire head can move over the course of a respiratory therapy session.

[0038] Due to these challenges, some masks suffer from one or more of the following problems: protrusion, unattractiveness, expense, disproportion, difficulty of use, and discomfort, particularly when worn for a long period of time or when the patient is not familiar with the system. A mask that is not the right size can cause reduced compliance, decreased comfort, and adverse patient outcomes. Masks designed only for pilots, masks designed to be part of personal protection equipment, such as filtering masks, SCUBA masks, or masks designed for the administration of anaesthetics can be acceptable for their original purpose, but are not ideally comfortable for long periods of wear, such as hours. This discomfort can lead to reduced patient compliance with therapy. This is particularly true if the mask is worn during sleep.

[0039] CPAP therapy is very effective for treating certain respiratory disorders, assuming patient compliance. If the mask is uncomfortable or difficult to use, the patient can not comply with therapy. Since it is typically recommended that patients clean their masks on a regular basis, if the mask is difficult to clean (e.g., difficult to assemble or disassemble), the patient can not clean their mask, which can impact patient compliance.

[0040] While masks for other applications (e.g., pilots) can not be suitable for treating sleep disordered breathing, masks designed for treating sleep disordered breathing can be suitable for other applications.

[0041] For these reasons, patient interfaces for delivering CPAP during sleep form a distinct field.

[0042] 2.2.3.1.1 Seal-forming structure

[0043] A patient interface can include a seal-forming portion. Because of its direct contact with the patient’s face, the shape and configuration of the seal-forming structure can directly impact the effectiveness and comfort of the patient interface.

[0044] A patient interface is characterized, in part, by the design intent of the seal-forming structure in use to interface with the face. In one form of patient interface, the seal-forming structure can include a first sub-portion to form a seal around the left nare and a second sub-portion to form a seal around the right nare. In one form of patient interface, the seal-forming portion can include a single element that in use surrounds both nare. Such a single element can be designed to cover, for example, the upper lip region and the bridge of the nose region of the face. In one form of patient interface, the seal-forming structure can include an element that in use surrounds the mouth region, for example, by forming a seal on the lower lip region of the face. In one form of patient interface, the seal-forming structure can include a single element that in use surrounds both nare and the mouth region. These different types of patient interfaces can be given various names by their manufacturers, including nasal masks, full-face masks, nasal pillows, nasal puffs, and mouth-nose masks.

[0045] A seal-forming structure that can be effective in one region of a patient’s face can not be suitable in another, for example, because of different shapes, structures, variations, and sensitive areas of a patient’s face. For example, a seal on a swimming goggle that covers a patient’s forehead can not be suitable for use on a patient’s nose.

[0046] Certain seal-forming structures can be designed for mass production, such that one design is suitable, comfortable, and effective for a wide range of different face shapes and sizes. To the extent there is a mismatch between the shape of a patient’s face and the seal-forming structure of a mass-produced patient interface, one or both must accommodate to form a seal.

[0047] One type of seal-forming structure extends around the periphery of the patient interface and is used to seal against the patient's face when the seal-forming structure is brought into face-contacting engagement with the patient's face while a force is applied to the patient interface. The seal-forming structure can comprise an air or fluid-filled cushion, or a molded or formed surface of an elastomeric (e.g. rubbery) sealing element. With this type of seal-forming structure, if the fit is not adequate, there will be gaps between the seal-forming portion and the face, and additional force will be required to force the patient interface against the face to achieve a seal.

[0048] Another type of seal-forming structure includes a thin material flap seal positioned around the periphery of the mask so as to provide a self-sealing action against the patient's face when positive pressure is applied within the mask. Similar to the previous form of seal-forming portion, if the fit between the face and the mask is not good, additional force can be required to achieve a seal, or the mask can leak. Furthermore, if the shape of the seal-forming structure does not match the shape of the patient, it can wrinkle or buckle in use, leading to leaks.

[0049] Another type of seal-forming structure can include a friction fit element, such as for insertion into the nostrils, however some patients find these uncomfortable.

[0050] Another form of seal-forming structure can use an adhesive to achieve a seal. Some patients can find it inconvenient to continually apply and remove adhesive to their face.

[0051] 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.

[0052] One form of nasal pillow is found in the Adam Circuit, which can be manufactured by Puritan Bennett. Another nasal pillow or nasal puff is the subject of U.S. Patent 4,782,832 (Trimble et al.) assigned to Puritan-Bennett Corporation.

[0053] ResMed Limited has manufactured the following products including nasal pillows: SWIFT® LT TM Nasal pillow mask, SWIFT® TM II Nasal pillow mask, SWIFT® TM LT Nasal pillow mask, SWIFT® TM FX nasal pillow mask and MIRAGE LIBERTY TMFull-face masks. The following patent applications assigned to ResMed Limited describe examples of nasal pillow masks: International Patent Application WO 2004 / 073,778 (which describes the ResMed Limited SWIFT® LT Nasal Pillow Mask TM other aspects of the SWIFT® LT Nasal Pillow), US Patent Application 2009 / 0044808 (which describes other aspects of the ResMed Limited SWIFT® LT Nasal Pillow TM ); International Patent Application WO 2005 / 063,328 and WO 2006 / 130,903 (which describe other aspects of the ResMed Limited MIRAGE LIBERTY® Full- Face Mask TM ); International Patent Application WO 2009 / 052,560 (which describes other aspects of the ResMed Limited SWIFT® FX Nasal Pillow). TM

[0054] 2.2.3.1.2 Positioning and stabilisation

[0055] Seal-forming structures of patient interfaces for positive air pressure therapy are subject to corresponding forces of air pressure to break the seal. Accordingly, various techniques have been used to position the seal-forming structure, and maintain it in sealing relationship with appropriate portions of the face.

[0056] One technique is to use adhesive. See, for example, US Patent Application Publication No. US 2010 / 0000534. However, the use of adhesive can be uncomfortable for some people.

[0057] Another technique is to use one or more straps and / or stabilising ligatures. Many such ligatures suffer from one or more of being unsuitable, bulky, uncomfortable and difficult to use.

[0058] 2.2.3.2 Respiratory pressure therapy (RPT) devices

[0059] Respiratory pressure therapy (RPT) devices can be used to implement one or more of a variety of therapies described above, such as by producing a flow of air for delivery to an entrance to the airways of a patient. The flow of air can be pressurised. Examples of RPT devices include CPAP devices and ventilators.

[0060] Air pressure generators are known in a range of applications, such as industrial scale ventilation systems. However, medical air pressure generators have particular requirements not met by more general air pressure generators, such as reliability, size and weight requirements of medical devices. In addition, even devices designed for medical use can have shortcomings with respect to one or more of: comfort, noise, ease of use, efficacy, size, weight, manufacturability, cost and reliability.

[0061] An example of a particular requirement of certain RPT devices is noise. ​

[0062] Noise output levels table for existing RPT devices (only one sample, measured at 10 cmH20 using test method specified in ISO 3744 in CPAP mode).

[0063] RPT device name A-weighted sound pressure level dB(A) Years (approx.) C Series Tango TM ]] 31.9 2007 C Series Tango with humidifier TM ]]> 33.1 2007 [SCS8 Escape TM II]] 30.5 2005 H4i TM S8 Escape of humidifier TM ]]> 31.1 2005 [S9 AutoSet TM ]]> 26.5 2010 S9 AutoSet with H5i humidifier TM ]] 28.6 2010

[0064] 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™ Series of Adult and Paediatric Ventilators can provide support for invasive and non-invasive non- dependent ventilation for a range of patients for the treatment of a number of conditions such as, but not limited to, NMD, OHS and COPD. TM Ventilators such as the ResMed Stellar™ Series of Adult and Paediatric Ventilators can provide support for invasive and non-invasive non- dependent ventilation for a range of patients for the treatment of a number of conditions such as, but not limited to, NMD, OHS and COPD.

[0065] ResMed Elisée TM 150 Ventilator and ResMed VS III TM Ventilators can provide support for invasive and non-invasive dependent ventilation for adult or paediatric patients for the treatment of a number of diseases. These ventilators provide volume and pressure ventilation modes with single or dual limb circuits. RPT devices generally comprise a pressure generator, for example an electrically powered blower or a compressed gas reservoir, and are constructed and arranged to supply a flow of air to the airways of a patient. In some cases, the flow of air can be supplied to the airway of a patient at positive pressure. The outlet of the RPT device is connected via an air circuit to a patient interface, such as those described above.

[0066] The designer of the device can be presented with an infinite number of choices to make. Design criteria often conflict, meaning that some design choices are far from routine or inevitable. In addition, comfort and efficacy in some areas can be highly sensitive to small and subtle changes in one or more parameters.

[0067] 2.2.3.3 Humidifier

[0068] Delivery of a flow of air without humidification can cause drying of the airways. The use of a humidifier with an RPT device and patient interface results in humidified gas that minimizes drying of the nasal mucosa and increases patient airway comfort. In addition, in cooler climates, warm air is generally more comfortable to apply into and around the facial area of the patient interface than cold air.

[0069] A range of artificial humidification devices and systems are known, but they can not meet the special requirements of a medical humidifier.

[0070] Medical humidifiers are used to increase the humidity and / or temperature of an air flow relative to ambient air when required, typically where a patient can be asleep or resting, for example in a hospital. Medical humidifiers for bedside placement can be small. Medical humidifiers can be configured to only humidify and / or heat the air flow delivered to the patient, without humidifying and / or heating the patient's surroundings. Room-based systems, for example a sauna, air conditioner or evaporative cooler, for example, can also humidify air breathed by a patient, however these systems also humidify and / or heat the entire room, which can cause discomfort to the occupants. Furthermore, medical humidifiers can have more stringent safety limits than industrial humidifiers.

[0071] While many medical humidifiers are known, they can have one or more shortcomings. Some medical humidifiers can provide inadequate humidification, some can be difficult or inconvenient for a patient to use.

[0072] 2.2.3.4 Data management

[0073] There can be many clinical reasons to obtain data that determines whether a patient prescribed to undergo treatment with respiratory therapy is "compliant", for example that the patient has used their RPT device according to certain "compliance rules". One example of compliance rules for CPAP therapy is that a patient is required to use the RPT device for at least four hours each night, continuously for at least 21 or 30 days, in order for the patient to be compliant. In order to determine the compliance of a patient, a provider of the RPT device, such as a health care provider, can manually obtain data describing the treatment of the patient using the RPT device, calculate the usage over a predetermined period of time and compare to the compliance rules. Once the health care provider has determined that the patient has used their RPT device according to the compliance rules, the health care provider can inform a third party that the patient is compliant.

[0074] There are other aspects of patient treatment that can benefit from communication of treatment data to a third party or external system.

[0075] Existing methods of communicating and managing such data can be one or more of the following: expensive, time consuming and error prone.

[0076] 2.2.3.5 Mandibular repositioning

[0077] 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 lower jaw (mandible) in a forward position during sleep. The MRD is a removable device that the patient inserts into their mouth before going to sleep and takes out after sleeping. Thus, the MRD is not designed to be worn all the time. The MRD can be custom made or produced in a standard form and includes bite impression portions designed to allow fitting to the patient's teeth. This mechanical protrusion of the lower jaw enlarges the space behind the tongue, exerts tension on the pharyngeal walls to reduce collapse of the airway, and reduces vibration of the upper palate.

[0078] In certain examples, a mandibular advancement device can include an upper splint intended to engage or mate with teeth on the upper jaw or maxilla and a lower splint intended to engage or mate with teeth on the upper or lower jaw. The upper and lower splints are laterally connected together by a pair of connecting rods. The pair of connecting rods are symmetrically fixed to the upper and lower splints.

[0079] In this design, the length of the connecting rods is chosen so that when the MRD is placed in the patient's mouth, the lower jaw is held in an advanced position. The length of the connecting rods can be adjusted to change the degree of protrusion of the lower jaw. The degree of protrusion of the lower jaw can be determined by a dentist, who will determine the length of the connecting rods.

[0080] Some MRDs are constructed to push the lower jaw forward relative to the upper jaw, while other MADs (such as the ResMed Narval CC TM MRDs are designed to hold the lower jaw in a forward position. The device also reduces or minimizes the side effects on the dentition and the temporomandibular joint (TMJ). Thus, it is constructed to minimize or prevent any movement of one or more teeth.

[0081] 2.2.3.6 Exhaust port technology

[0082] Some forms of treatment systems can include an exhaust port to allow flushing of exhaled carbon dioxide. The exhaust port can allow gas to flow from an interior space of the patient interface (e.g. a plenum chamber) to an exterior space of the patient interface, e.g. to the environment.

[0083] The exhaust port can include an orifice, and gas can flow through the orifice when the mask is in use. Many such exhaust ports are noisy. Others can become blocked in use, providing insufficient flushing. Some exhaust ports can disrupt the sleep of a bed partner 1100 of the patient 1000, e.g. through noise or a focussed gas flow.

[0084] Rudolph Medical has developed a number of improved mask vent technologies. See International Patent Application Publication No. WO 1998 / 034,665; International Patent Application Publication No. WO 2000 / 078,381; U.S. Patent No. 6,581,594; U.S. Patent Application Publication No. US 2009 / 0050156; U.S. Patent Application Publication No. US 2009 / 0044808.

[0085] Noise figures for existing masks (ISO 17510-2:2007, pressure of 10 cm H20 at 1 m)

[0086]

[0087] (* only for samples, measured at 10 cm H20 using test method specified in ISO 3744 in CPAP mode)

[0088] Sound pressure values for various objects are shown below

[0089]

[0090]

[0091] 2.2.4 Diagnosis and monitoring systems

[0092] Polysomnography (PSG) is a conventional system for diagnosing and monitoring cardiopulmonary disorders, and typically involves a professional clinician applying the system. PSG typically involves placing 15 to 20 contact sensors on a patient in order to record various body signals, such as electroencephalogram (EEG), electrocardiogram (ECG), electrooculogram (EOG), electromyogram (EMG), etc. PSG for sleep disordered breathing has involved two nights of patient observation in a clinic, one night purely for diagnosis and a second night for determination of treatment parameters by a clinician. PSG is therefore expensive and inconvenient. In particular, it is not suitable for home sleep testing.

[0093] A clinical specialist can properly diagnose or monitor a patient based on visual observation of PSG signals. However, there are situations in which a clinical specialist can not be available or can not be affordable. Different clinical specialists can disagree on a patient's condition. In addition, a given clinical specialist can apply different criteria at different times. 3 SUMMARY

[0095] The present technology is directed towards medical devices for diagnosing, ameliorating, treating or preventing a respiratory disorder, with one or more of improved comfort, cost, efficacy, ease of use, and manufacturability.

[0096] A first aspect of the present technology relates to apparatus for diagnosing, ameliorating, treating or preventing a respiratory disorder.

[0097] Another aspect of the present technology relates to methods for diagnosing, ameliorating, treating or preventing a respiratory disorder.

[0098] One aspect of certain forms of the present technology is to provide methods and / or apparatus to improve patient compliance with respiratory therapy.

[0099] One aspect of the present technology relates to a water reservoir for a humidifier, the water reservoir comprising a non-metallic film base adapted to be in thermal engagement with a heater plate. The film base of the water reservoir is configured to provide an arrangement that reduces the production cost of the water reservoir while maintaining or improving its heat transfer characteristics and its reliability. In one example, the film base can be thin and flat enough to provide good thermal contact and good humidifier performance and to allow selection of suitable materials, for example, depending on the requirements and performance of the humidifier.

[0100] One aspect of the present technology relates to a water reservoir for a humidifier for a flow of breathable gas, the water reservoir comprising a reservoir base comprising a cavity configured to contain a volume of liquid and an electrically conductive portion disposed on the base. The electrically conductive portion is adapted to be in thermal engagement with a heater plate to allow heat to be transferred from the heater plate to the volume of liquid. The electrically conductive portion comprises a film comprising a non-metallic material, the film having a wall thickness of less than about 1 mm.

[0101] In one example, the film can have a wall thickness of less than about 0.5 mm. In one example, the film can comprise a silicone, polycarbonate, or other thermoplastic or elastomeric material. In one example, the film can be provided as a separate and distinct structure from the reservoir base. In one example, the film comprises a pre-formed structure that is secured or otherwise provided to the reservoir base. In one example, the reservoir base can comprise a hole configured to receive the film. In one example, the film can comprise a shape that corresponds to the shape of the hole. In one example, the film can be generally planar. In one example, the film can comprise a first side adapted to form an inner bottom surface of a water reservoir exposed to a volume of liquid and a second side opposite the first side adapted to form an outer bottom surface of the water reservoir exposed to a heater plate. In one example, the second side of the film can provide a contact surface configured and arranged to directly interface with the heater plate. In one example, the non-metallic material of the film can be similar to the material of the reservoir base. In one example, the wall thickness of the film can be less than the wall thickness of the walls of the reservoir base. In one example, the water reservoir can further comprise one or more ribs configured and arranged to extend through the film so as to create a force adapted to urge the film toward the heater plate. In one example, the reservoir base can comprise a base upper body, a base bottom plate, and a film that together form a cavity. In one example, the water reservoir can further comprise a reservoir lid movably connected to the reservoir base to allow the water reservoir to be transitionable between an open configuration and a closed configuration.

[0102] Another aspect of the present technology relates to a water reservoir for a device for humidifying a flow of breathable gas, comprising a reservoir base comprising a cavity configured to hold a volume of liquid and an electrically conductive portion disposed on the base. The electrically conductive portion is adapted to thermally interface with a heater plate to allow heat to be thermally transferred from the heater plate to the volume of liquid. The electrically conductive portion comprises a film comprising a non-metallic material. The film is provided as a separate and distinct structure from the reservoir base and the film has a wall thickness that is less than a wall thickness of the walls of the reservoir base. In one example, the film can comprise a pre-formed structure that is secured or otherwise provided to the reservoir base.

[0103] One aspect of one form of the present technology is a method of manufacturing a device.

[0104] One aspect of certain forms of the present technology is a medical device that is easy to use, for example, by a person who is not medically trained, a person with limited dexterity, a person with limited vision, or a person with limited experience using such medical devices.

[0105] One aspect of one form of the present technology is a patient interface that can be washed in a patient's home, for example in soapy water, without requiring specialised cleaning equipment. One aspect of one form of the present technology is a humidifier tank that can be washed in a patient's home, for example in soapy water, without requiring specialised cleaning equipment.

[0106] The methods, systems, devices and apparatuses described in this document can provide improved functionality in a processor, such as a processor of a special purpose computer, a respiratory monitor and / or a respiratory treatment apparatus. Moreover, the described methods, systems, devices and apparatuses can provide improvements in the technical field of automated management, monitoring and / or treatment of respiratory disorders, including, for example, sleep disordered breathing.

[0107] Of course, parts of these aspects can form sub-aspects of the present technology. Moreover, the various sub-aspects and / or aspects can be combined in various ways and also form further aspects or sub-aspects of the present technology.

[0108] Other features of the technology will be apparent from consideration of the following detailed description, abstract, drawings and claims. 4BRIEF DESCRIPTION OF DRAWINGS

[0110] The technology is illustrated in the drawings going from example to example and not limitation in which like reference numerals denote like elements in the various figures including:

[0111] 4.1PROCESSING SYSTEM

[0112] Figure 1A A system is shown including a patient 1000 wearing a patient interface 3000 in the form of a nasal pillows receiving a supply of air at positive pressure from an RPT device 4000. Air from the RPT device 4000 is humidified in a humidifier 5000 and passes along an air circuit 4170 to the patient 1000. A bed partner 1100 is also shown. The patient is sleeping in a supine position.

[0113] Figure 1B A system is shown including 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. Air from the RPT device is humidified in a humidifier 5000 and passes along an air circuit 4170 to the patient 1000.

[0114] Figure 1C A system is shown including a patient 1000 wearing a patient interface 3000 in the form of a full-face mask receiving a supply of air at positive pressure from an RPT device 4000. Air from the RPT device is humidified in a humidifier 5000 and passes along an air circuit 4170 to the patient 1000. The patient is sleeping in a side position.

[0115] 4.2 Respiratory system and facial anatomy

[0116] Figure 2A A schematic diagram of the human respiratory system is shown, including the nasal and oral cavities, larynx, vocal folds, esophagus, trachea, bronchi, lungs, alveolar sacs, heart, and diaphragm.

[0117] Figure 2B A view of the upper airways of a human is shown, including the nasal cavity, nasal bone, lateral nasal cartilage, greater alar cartilage, nostril, upper lip, lower lip, larynx, hard palate, soft palate, pharynx, tongue, epiglottic cartilage, vocal folds, esophagus, and trachea.

[0118] 4.3 Patient interface

[0119] Figure 3A A patient interface in the form of a nasal mask according to one form of the present technology is shown.

[0120] Figure 3B A schematic diagram of a cross-section through a structure at a point is shown. The outward normal at the point is indicated. The curvature at the point has a positive sign and a relatively large magnitude when compared to the curvature magnitude shown. Figure 3C

[0121] A schematic diagram of a cross-section through a structure at a point is shown. The outward normal at the point is indicated. The curvature at the point has a positive sign and a relatively small magnitude when compared to the curvature magnitude shown. Figure 3C Figure 3B A schematic diagram of a cross-section through a structure at a point is shown. The outward normal at the point is indicated. The curvature at the point has a zero value.

[0122] Figure 3D A schematic diagram of a cross-section through a structure at a point is shown. The outward normal at the point is indicated. The curvature at the point has a negative sign and a relatively small magnitude when compared to the curvature magnitude shown.

[0123] Figure 3E Figure 3F A schematic diagram of a cross-section through a structure at a point is shown. The outward normal at the point is indicated. The curvature at the point has a negative sign and a relatively large magnitude when compared to the curvature magnitude shown.

[0124] Figure 3F A schematic diagram of a cross-section through a structure at a point is shown. The outward normal at the point is indicated. The curvature at the point has a negative sign and a relatively large magnitude when compared to the curvature magnitude shown. Figure 3E

[0125] Figure 3G A cushion for a mask including two pillows is shown. The outer surface of the cushion is indicated. The edge of the surface is indicated. The domed region and the saddle region are indicated.

[0126] Figure 3H ​​​A cushion for a face mask is shown. An outer surface of the cushion is indicated. An edge of the surface is indicated. A path on the surface between point A and point B is indicated. A straight-line distance between point A and point B is indicated. Two saddle regions and a domed region are indicated.

[0127] Figure 3I A surface of a structure is shown, in which the surface has a one-dimensional hole. The planar curve forms a boundary of the one-dimensional hole.

[0128] Figure 3J A cross-section through Figure 3I of a structure is shown. The surface shown defines a two-dimensional hole in the structure. Figure 3I

[0129] Figure 3K A perspective view of Figure 3I of a structure is shown, which structure includes a two-dimensional hole and a one-dimensional hole. The surface defining the two-dimensional hole in the structure is also shown. Figure 3I

[0130] Figure 3L A face mask with an inflatable bladder as a cushion is shown.

[0131] Figure 3M A cross-section through Figure 3L of a face mask is shown, and the inner surface of the bladder is shown. The inner surface defines a two-dimensional hole in the face mask.

[0132] Figure 3N Another cross-section through Figure 3L of a face mask is shown. The inner surface is also indicated.

[0133] Figure 3O The left-hand rule is shown.

[0134] Figure 3P The right-hand rule is shown.

[0135] Figure 3Q The left ear, including the left-ear spiral, is shown.

[0136] Figure 3R The right ear, including the right-ear spiral, is shown.

[0137] Figure 3S The right-hand spiral is shown.

[0138] Figure 3T A face mask view is shown, which includes a twist sign of a space curve defined by edges of a sealing membrane in different regions of the face mask.

[0139] 4.4 RPT device

[0140] Figure 4A An RPT device according to one form of the present technology is shown.​​

[0141] 4.5 humidifier

[0142] Figure 5 is a perspective view of an RPT device and integrated humidifier according to an example of the technology, and showing engagement of the humidifier with the air circuit according to an example of the technology.

[0143] Figure 6 is a perspective view of an RPT device and integrated humidifier of Figure 5 , showing engagement of the humidifier reservoir with the reservoir base according to an example of the technology.

[0144] Figure 7 is another perspective view of an RPT device and integrated humidifier of Figure 5 .

[0145] Figure 8 is another perspective view of an RPT device and integrated humidifier of Figure 5 , showing engagement of the humidifier reservoir with the reservoir base according to an example of the technology.

[0146] Figures 9 to 12 shows various views of a humidifier reservoir according to an example of the technology, wherein, Figures 9 to 11 shows the humidifier reservoir in a closed configuration, Figure 12 shows the humidifier reservoir in an open configuration.

[0147] Figure 13 is a top perspective view of a reservoir base of a humidifier reservoir according to an example of the technology.

[0148] Figure 14 is a bottom perspective view of the reservoir base of Figure 13 .

[0149] Figure 15 is an exploded view of the reservoir base of Figure 13 .

[0150] Figure 16 is a cross-sectional view of a humidifier reservoir including the reservoir base of Figure 13 according to an example of the technology.

[0151] Figure 17 is a cross-sectional view of a base chassis and conductive portion of the reservoir base of Figure 13 according to an example of the technology.

[0152] Figure 18 is a top perspective view of a reservoir base of a humidifier reservoir according to another example of the technology.

[0153] Figure 19 is a bottom perspective view of the reservoir base of Figure 18Figure 19 is a bottom perspective view of a reservoir base of the reservoir of Figure 18.

[0154] Figure 20 Figure 22 is a cross-sectional view of a base floor and conductive portion of the reservoir base of Figure 21, according to an example of the present technology. Figure 18

[0155] Figure 21 Figure 23 shows a schematic view of a humidifier according to an example of the present technology. 5DETAILED DESCRIPTION

[0157] Before the present technology is described in further detail, it is to be understood that the technology is not limited to the particular examples described herein, which can vary. It is also to be understood that the terminology used herein is for the purpose of describing particular examples only, and is not intended to be limiting.

[0158] The following description provides examples that relate to various examples that can share one or more common characteristics and / or features. It is understood that one or more features of any one example can be combinable with one or more features of another or other examples. In addition, any single feature or combination of features in any of the examples can constitute further examples.

[0159] 5.1 TREATMENT

[0160] In one form, the technology comprises a method of treating a respiratory disorder, the method including the step of applying positive pressure to an entrance to the airways of a patient 1000.

[0161] In certain examples of the technology, a supply of air at positive pressure is provided to the nasal passages of a patient via one or both nares.

[0162] In certain examples of the technology, oral breathing is limited, restricted or prevented.

[0163] 5.2 TREATMENT SYSTEM

[0164] In one form, the technology comprises an apparatus or device for treating a respiratory disorder. The apparatus or device can comprise an RPT device 4000 for supplying pressurised air to a patient 1000 via an air circuit 4170 to a patient interface 3000, for example, see Figures 1A to 1C .

[0165] 5.3 PATIENT INTERFACE

[0166] As Figure 3A ​As shown, the non-invasive patient interface 3000 according to an aspect of the present technology comprises the following functional aspects: a seal-forming structure 3100, a plenum chamber 3200, a positioning and stabilising structure 3300, an exhaust port 3400, a form of connection port 3600 for connection to an air circuit 4170, and a forehead support 3700. In some forms, a functional aspect can be provided by one or more physical components. In some forms, one physical component can provide one or more functional aspects. In use, the seal-forming structure 3100 is arranged to surround the entrance to the airways of the patient so as to facilitate the supply of air at positive pressure to the airways.

[0167] A patient interface can not be suitable for use in respiratory pressure therapy if it does not comfortably deliver a minimum level of positive pressure to the airways.

[0168] A patient interface 3000 according to one form of the present technology is constructed and arranged to be capable of providing a supply of air at a positive pressure of at least 6 cmH20 relative to ambient.

[0169] A patient interface 3000 according to one form of the present technology is constructed and arranged to be capable of providing a supply of air at a positive pressure of at least 10 cmH20 relative to ambient.

[0170] A patient interface 3000 according to one form of the present technology is constructed and arranged to be capable of providing a supply of air at a positive pressure of at least 20 cmH20 relative to ambient.

[0171] 5.4 RPT device

[0172] An RPT device 4000 according to an aspect of the present technology comprises mechanical, pneumatic, and / or electrical components and is configured to execute one or more algorithms, for example, see Figure 4A The RPT device 4000 can be configured to generate a flow of air for delivery to the airways of a patient, for example, for treatment of one or more of the respiratory conditions described elsewhere in this document.

[0173] In one form, the RPT device 4000 is constructed and arranged to be capable of delivering a flow of air in the range -20 L / min to +150 L / min while maintaining a positive pressure of at least 6 cmH20, or a positive pressure of at least 10 cmH20, or a positive pressure of at least 20 cmH20.

[0174] The power supply can be located internal or external to the housing of the RPT device 4000.

[0175] In one form of the present technology, the power supply provides power to the RPT device only. In another form of the present technology, the power supply provides power to the RPT device 4000 and the humidifier 5000.

[0176] In one form of the technology, the RPT device 4000 comprises a central controller comprising one or more processors adapted to control the RPT device 4000.

[0177] Suitable processors can include x86 INTEL processors, ARM Holdings based processors, such as the Cortex-M series of processors, or processors based on the ARC Processors such as the STM32 series of microcontrollers from ST MICROELECTRONICS. In certain alternative forms of the technology, 32-bit RISC CPUs such as the STR9 series of microcontrollers from ST MICROELECTRONICS, or 16-bit RISC CPUs such as the MSP430 series of microcontrollers manufactured by TEXAS INSTRUMENTS, are also suitable.

[0178] In one form of the technology, the central controller is a dedicated electronic circuit.

[0179] In one form, the central controller is an application specific integrated circuit. In another form, the central controller comprises discrete electronic components.

[0180] The central controller can be configured to receive input signals from one or more transducers, one or more input devices, and the humidifier 5000.

[0181] The central controller can be configured to provide output signals to one or more of the output devices, the therapy device controller, the data communication interface, and the humidifier 5000.

[0182] In some forms of the technology, the central controller is configured to implement one or more methods described herein, such as one or more algorithms expressed as computer programs stored in a non-transitory computer readable storage medium, such as a memory. In some forms of the technology, the central controller can be integrated with the RPT device 4000. However, in some forms of the technology, some methods can be performed by a remotely located device. For example, a remotely located device can determine a control setting for a ventilator or detect a respiratory related event by analysing stored data from any of the sensors described herein.

[0183] 5.5 Air circuit

[0184] The air circuit 4170 according to an aspect of the technology is a conduit or tube which, in use, is constructed and arranged to allow a flow of air to flow between two components, such as the RPT device 4000 and the patient interface 3000.

[0185] In particular, the air circuit 4170 can be in fluid connection with the outlet of the pneumatic block and the patient interface. The air circuit can be referred to as an air delivery tube. In some cases, there can be separate circuits for inhalation and exhalation. In other cases, a single limb is used.

[0186] In certain forms, the air circuit 4170 can include one or more heating elements configured to heat air in the air circuit, for example to maintain or increase the temperature of the air. The heating elements can be in the form of a heating wire circuit, and can include one or more transducers, such as temperature sensors. In one form, the heating wire circuit can be helically wound around the axis of the air circuit 4170. The heating elements can be in communication with a controller, such as a central controller. One example of an air circuit 4170 including a heating wire circuit is described in US Patent Application 8,733,349, which is incorporated herein by reference in its entirety.

[0187] 5.6 Humidifier

[0188] 5.6.1 Humidifier Overview

[0189] In one form of the technology, a humidifier is provided to change the absolute humidity of air or gas delivered to a patient relative to ambient air. Typically, the humidifier is used to increase the absolute humidity and to increase the temperature of the air stream (relative to ambient air) before delivery to the patient's airways.

[0190] Figures 5 to 8 An RPT device 4000 and an integrated humidifier 5000 according to an example of the technology is shown. In the example shown, the humidifier 5000 includes a water reservoir dock 5130 configured to receive a water reservoir 5110. As shown, the water reservoir dock 5130 includes a cavity 5160 formed therein to receive the water reservoir 5110, for example, the water reservoir 5110 can be inserted / removed from the water reservoir dock 5110 in a transverse direction.

[0191] In the example shown, the RPT device 4000 is integrated with the humidifier 5000. For this arrangement, the water reservoir dock 5130 is configured to connect the water reservoir 5110 to the pneumatic path. Preferably, as shown Figure 5 and 8 The water reservoir dock 5130 includes a dock air outlet 5168 for delivering an air stream to the water reservoir 5110, a dock air inlet 5170 for receiving an air stream that has been humidified in the water reservoir 5110, and a humidifier outlet 5172 for passing the humidified air stream to the air circuit 4170. The cavity 5160 can include a top portion configured to cover at least a portion of a lid of the water reservoir 5110, and a bottom portion including the heater plate 5120.

[0192] However, it will be appreciated that the water reservoir dock 5130 can be provided separately to the RPT device 4000 in alternative arrangements. In such arrangements, an additional interface can be used to connect the water reservoir dock 5130 to the RPT device 4000, for example, directly coupled or coupled via the air circuit.

[0193] In another arrangement, the water reservoir dock 5130 can comprise an opening in a substantially horizontal plane, such that the water reservoir 5110 can be inserted from above or below the water reservoir dock 5130.

[0194] Further examples and details of such RPT devices 4000 and integrated humidifiers 5000 are described in PCT Publication No. WO2014 / 138804, published on 18 September 2014, the entire contents of which are incorporated herein by reference.

[0195] 5.6.2 Humidifier assembly

[0196] 5.6.2.1 Water reservoir

[0197] Figures 9 to 12 A form of water reservoir or bucket 5110 is shown, which comprises a reservoir dock 5112, a reservoir lid 5114 and an intermediate portion comprising a compliant portion 5116. The water reservoir 5110 comprises a cavity (e.g. provided by the dock) which is configured to hold or retain a volume of liquid (e.g. water) to be vaporised to humidify an air flow. The water reservoir 5110 can be configured to hold a predetermined maximum volume of water in order to provide sufficient humidification for the duration of at least a respiratory treatment session (e.g. for one night). Typically, the reservoir 5110 is configured to hold several hundred millilitres of water, for example 300 millilitres (ml), 325 ml, 350 ml or 400 ml. In other forms, the humidifier 5000 can be configured to receive a supply of water from an external water source (e.g. a building’s water supply system).

[0198] According to one aspect, the water reservoir 5110 is configured to add moisture to an air flow from the RPT device 4000 as the air flow passes therethrough. In one form, the water reservoir 5110 can be configured to cause the air flow to pass through the reservoir 5110 in a tortuous path while in contact with a volume of water therein.

[0199] The reservoir 5110 can also be configured to resist the flow of liquid therefrom, for example when the reservoir 5110 is displaced and / or rotated from its normal working orientation, for example through any apertures and / or between sub-components thereof. As the air flow to be humidified by the humidifier 5000 is typically pressurised, the reservoir 5110 can also be configured to prevent loss of pneumatic pressure through leakage and / or flow impedance.

[0200] In the illustrated example, the reservoir cover 5114 includes an inlet 5118 for receiving a flow of air into the reservoir 5110 and an outlet 5122 for delivering a flow of air from the reservoir 5110. The reservoir cover 5114 can be pivotally connected to the base 5112 by a hinge 5158 to allow the reservoir 5110 to transition between a closed configuration (as shown in Figures 9 to 11 FIG. 1) and an open configuration (as shown in Figure 12 FIG. 2). When the water reservoir 5110 is in its closed configuration, the compliant portion 5116 makes a sealing engagement between the base 5112 and the cover 5114 to seal the base 5112 and the cover 5114 and prevent water from flowing out of the reservoir 5110. The compliant portion 5116 can also perform other functions, such as improving thermal contact between the reservoir 5110 and the heater plate 5120.

[0201] The reservoir base 5112 can be configured as a container to retain a given maximum volume of liquid that the reservoir 5110 is configured to hold. In one form, the base 5112 can include other features, such as an anti-overflow feature, for example, at least one aperture 5138 in the water reservoir 5110 to indicate overfilling, as shown in Figure 13 FIG. 3.

[0202] In one form, the reservoir base 5112 can also include an inner lip 5224 and / or an outer lip 5226, for example, as shown in Figure 13 FIG. 4. According to one aspect, the inner lip 5224 and / or the outer lip 5226 can prevent liquid from flowing out of the reservoir 5110 through the interface between the intermediate portion (e.g., the compliant portion 5116) and the base 5112, for example, when the intermediate portion is compressed, or when the intermediate portion is in vibration.

[0203] In one form, the reservoir base 5112 includes a base upper body 5146, a base floor 5148, and a conductive portion 5152, which together form a container, for example, see Figure 15 However, it should be understood that the reservoir base 5112 can be constructed of any number of components.

[0204] In one example, the base upper body 5146, the base floor 5148, and / or the cover 5114 can be constructed of a biocompatible material suitable for holding a volume of liquid, for example, a plastic or a thermoplastic polymer, for example, an acrylonitrile butadiene styrene (ABS) or a polycarbonate material.

[0205] In one example, a sealing element can be disposed between, for example, the base upper body 5146 and the base floor 5148 to prevent water from flowing out of the water reservoir 5110, and in particular, from the base 5112.

[0206] Other instances and details of such water storage devices are described in PCT Publication WO2014 / 138804, published on 18 September 2014, which is incorporated herein by reference in its entirety.

[0207] 5.6.2.2 Conductive Parts

[0208] According to an example of the present technology, the reservoir 5110 includes a conductive portion 5152 configured to allow heat to be efficiently transferred from the heater plate 5120 to a volume of liquid within the reservoir 5110. The conductive portion 5152 includes a thermally conductive material configured and arranged to be thermally bonded or in contact with the heater plate 5152 to allow heat to be thermally transferred from the heater plate to the volume of liquid.

[0209] exist Figures 13 to 20 In the example shown, the conductive portion 5152 includes a thin film (also referred to as a film base or base conductor film) comprising a thermally conductive nonmetallic material, which is configured to be thermally coupled to the heater plate 5120 of the humidifier 5000.

[0210] In one example, the thermally conductive nonmetallic material of the film 5152 may include silicone resin, polycarbonate, or other thermoplastic or elastomer materials.

[0211] In one example, film 5152 may include a thickness of about 0.05 mm to 1.5 mm, such as 0.10 mm to 0.125 mm. In another example, the thickness of the film may be less than about 1 mm, such as less than about 0.5 mm. In one form, the film may include a silicone resin (LSR) film with a thickness of about 0.4 mm.

[0212] In the example shown, the base plate 5148 includes a sidewall 5149.1 extending around the periphery of the base plate and a bottom wall 5149.2 connecting the sidewall 5149.1, see, for example, [reference needed]. Figure 17 The membrane 5152 is disposed or otherwise incorporated into the bottom wall 5149.2 to form a container for retaining liquid. In the example shown, the bottom wall 5149.2 includes a hole 5149.3 configured to receive the membrane 5152, see, for example, [link to example]. Figure 15 The membrane 5152 is sealed in and / or on the orifice 5149.3 in the operating position to form at least a portion of the container base and prevent water from flowing out of the water reservoir 5110.

[0213] For example, the membrane 5152 can include a shape that corresponds to the shape of the aperture 5149.3, such that the inner surface defining the aperture 5149.3 is fixed at the edge of the membrane 5152 at the perimeter. Alternatively, the membrane 5152 can include a shape that is different than the shape of the aperture 5149.3, such that the edge of the membrane 5152 at the perimeter extends beyond the edge of the aperture 5149.3, e.g., the membrane 5152 overlaps the bottom wall 5149.2 of the base floor 5148. In the illustrated example, the membrane 5152 includes a shape, e.g., a rectangle, that generally corresponds to the shape of the heater plate 5120, however other suitable shapes are possible, e.g., a square, a circle, an oval.

[0214] As shown, the membrane 5152 includes a first side 5152.1 that is adapted to form the bottom inner surface of the reservoir 5110 that is exposed to water. The membrane 5152 includes a second side 5152.2 that is opposite the first side 5152.1 that is adapted to form the bottom outer surface of the reservoir 5110 that is exposed to the heater plate 5120, e.g., the second side 5152.2 of the membrane 5152 provides a contact surface that is configured and arranged to directly engage the heater plate 5120.

[0215] In the illustrated example, the membrane 5152 is generally planar and disposed at the bottom of the reservoir. However, the membrane 5152 can include a non-planar shape and can be disposed in other areas of the reservoir, e.g., along a sidewall of the reservoir that is exposed to water. In one example, the membrane 5152 can overlap one or more walls of the base floor 5148, e.g., the membrane extends through an aperture in the base floor and is shaped to conform to and overlap the bottom and / or sidewalls of the base floor 5148.

[0216] In one example, the membrane 5152 is provided as a separate and distinct structure from the base floor 5148 and then is fixed or otherwise provided to the base floor 5148 in the operational position, e.g., the membrane 5152 includes a pre-formed structure that is fixed to the base floor 5148.

[0217] In one example, the membrane 5152 can be pre-formed and then over-molded to the base floor 5148. In another example, the membrane 5152 can be pre-formed and then fixed to the base floor 5148, e.g., by an adhesive or welding. In yet another example, the membrane 5152 can be provided to the base floor 5148 by over-molding the membrane 5152 to the base floor 5148.

[0218] In one instance, the base plate 5148 may be removed, or the membrane may be otherwise supported or reinforced, for example, by at least one reinforcing strip of a material more rigid than the membrane, embedded or otherwise provided to the membrane. In one instance, the membrane may be provided to the upper body 5146 of the base, such that the membrane constitutes the entire bottom of the reservoir.

[0219] In an arrangement in which the preformed film 5152 is provided to the base plate 5148 (e.g., insert molding or adhesion), the film may comprise a thermoplastic polycarbonate film material (e.g., Makrofol DE 1-4 material with a thickness of about 0.1 mm), and the base plate 5148 may comprise a thermoplastic polycarbonate material (e.g., Makrolon 2458 (or Makrolon 2258) material). However, it should be understood that the preformed film and / or the base plate may comprise other suitable materials.

[0220] In one instance, the film may be filled with one or more additives to enhance thermal conductivity, in which case the film may be thicker, for example, to increase mechanical stability.

[0221] For example, the film may include plastic filled with ceramic powder or metal powder, or the film may include multiple films or layers, such as a sandwich laminate that includes a metal film and has a plastic film on one or both sides of the metal film.

[0222] In one example, a powder coating or spray coating of a thermally conductive material (e.g., metal) can be applied to the second side 5152.2 of the film facing the heater plate 5120 to improve thermal conductivity.

[0223] In one example, the film 5152 may have a thickness different from the thickness of the bottom and / or sidewalls of the base plate 5148; for example, the film's wall thickness may be less than the wall thickness of the bottom and / or sidewalls of the base plate 5148. This arrangement allows for appropriate selection of the film thickness to achieve desired performance characteristics, such as high flowability, humidification rate, and heating time.

[0224] In one example, the film 5152 may comprise a material similar to that of the upper body 5146 and / or the base plate, wherein the wall thickness of the film 5152 is less than the wall thickness of the upper body 5146 and / or the base plate 5148.

[0225] In one instance, such as Figures 18 to 20 As shown, the reservoir 5110 may be provided with one or more ribs 5175, which are constructed and arranged to extend through the membrane 5152 in order to generate a force suitable for pushing the membrane 5152 toward the heater plate 5120.

[0226] Alternatively or additionally, the humidifier can be provided with a spring-like element configured and arranged to urge the heater plate 5120 towards the film 5152.

[0227] The film base 5152 of the reservoir provides an arrangement that reduces the production cost of the reservoir while maintaining or improving its heat transfer characteristics and its reliability. For example, the film base is advantageous in that it can be thin and flat enough to provide good thermal contact and good humidifier performance and to allow selection of suitable materials, for example, depending on the requirements and performance of the humidifier.

[0228] In one example, the film base can be advantageous in that its non-metallic properties (e.g. thermoplastic or elastomeric material properties) provide corrosion resistance (e.g. protection from exposure to water) and a sealed connection with the base plate 5148 (e.g. forming a sealed reservoir for humidified water). Also, the non-metallic properties (e.g. thermoplastic or elastomeric material properties) of the film base can facilitate manufacture of the film base to present a complex shape, for example, the film base can be moulded into a complex shape if required to meet design requirements of the humidifier. Furthermore, in the case of a disposable reservoir, it is particularly desirable to reduce the production cost of the reservoir, where the reservoir is used for only a limited product life, where the reservoir is regularly replaced by a hospital, patient or user.

[0229] 5.6.2.3 Humidifier Reservoir Base

[0230] As described above, the humidifier 5000 can include a humidifier reservoir base 5130 (as Figures 5 to 8 shown) configured to receive a humidifier reservoir 5110. In certain arrangements, the humidifier reservoir base 5130 can include a locking feature configured to retain the reservoir 5110 in the humidifier reservoir base 5130.

[0231] 5.6.2.4 Water Level Indicator

[0232] The humidifier reservoir 5110 can include a water level indicator. In some forms, the water level indicator can provide one or more indications to a user (such as the patient 1000 or a caregiver) regarding the amount of water capacity in the humidifier reservoir 5110. The one or more indications provided by the water level indicator can include an indication of the maximum predetermined capacity of water, any portion thereof, such as 25%, 50%, 75% or a capacity such as 200ml, 300ml or 400ml.

[0233] 5.6.2.5 Humidifier Converter

[0234] As Figure 21As shown, in addition to the converter provided in the RPT device 4000, the humidifier 5000 may include one or more humidifier converters (sensors) 5210. For example... Figure 21 As shown, the humidifier converter 5210 may include one or more of an air pressure sensor 5212, an air flow converter 5214, a temperature sensor 5216, or a humidity sensor 5218. The humidifier converter 5210 may generate one or more output signals that can communicate with a controller (such as the central controller of the RPT device 4000 and / or the central humidifier controller 5250). In some forms, the humidifier converter may be located outside the humidifier 5000 (e.g., in the air circuit 4170) when communicating the output signal to the controller.

[0235] 5.6.2.5.1 Pressure Transmitter

[0236] In addition to the pressure converter provided in the RPT device 4000, one or more pressure converters 5212 may be provided to the humidifier 5000.

[0237] 5.6.2.5.2 Flow Converter

[0238] In addition to the flow sensor provided in the RPT device 4000, one or more flow converters 5214 may be provided to the humidifier 5000.

[0239] 5.6.2.5.3 Temperature Converter

[0240] The humidifier 5000 may include one or more temperature transducers 5216. The one or more temperature transducers 5216 may be configured to measure one or more temperatures, such as the temperature of the heating element 5240 and / or the temperature of the airflow downstream of the humidifier outlet. In some forms, the humidifier 5000 may further include a temperature sensor 5216 for detecting the ambient air temperature.

[0241] 5.6.2.5.4 Humidity Converter

[0242] In some forms, the humidifier 5000 may include one or more humidity sensors 5218 for detecting the humidity of a gas (such as ambient air). In some forms, the humidity sensor 5218 may be positioned toward the humidifier outlet to measure the humidity of the gas delivered from the humidifier 5000. The humidity sensor may be an absolute humidity sensor or a relative humidity sensor.

[0243] 5.6.2.6 Heating element

[0244] In some cases, a heating element 5240 can be provided to the humidifier 5000 to provide heat input to one or more of the water volume and / or the air stream in the humidifier reservoir 5110. The heating element 5240 can comprise a heat generating component such as an electrically resistive heating track. One suitable example of a heating element 5240 is a laminar heating element such as that described in PCT Patent Application Publication No. WO2012 / 171072, which is incorporated herein by reference in its entirety.

[0245] In some forms, the heating element 5240 can be provided in the humidifier base, where heat can be provided to the humidifier reservoir 5110 primarily by conduction.

[0246] 5.6.2.7 Humidifier controller

[0247] According to one arrangement of the present technology, as shown in Figure 21 The humidifier 5000 can include a humidifier controller 5250. In one form, the humidifier controller 5250 can be part of the central controller of the RPT device 4000. In another form, the humidifier controller 5250 can be a separate controller, which can communicate with the central controller.

[0248] In one form, the humidifier controller 5250 can receive, as input, measurements of characteristics of the air, water flow in the reservoir 5110 and / or humidifier 5000, such as temperature, humidity, pressure and / or flow rate. The humidifier controller 5250 can also be configured to execute or implement a humidifier algorithm and / or deliver one or more output signals.

[0249] As shown in Figure 21 The humidifier controller 5250 can include one or more controllers, such as a central humidifier controller 5251, a heating air circuit controller 5254 configured to control the temperature of the heating air circuit 4171 and / or a heating element controller 5252 configured to control the temperature of the heating element 5240.

[0250] 5.7 Glossary

[0251] To achieve the purposes of the present technology, one or more of the following definitions can apply in certain forms of the present technology. In other forms of the present technology, alternative definitions can apply.

[0252] 5.7.1 General

[0253] Air: In some forms of the present technology, air can be taken to mean atmospheric air, and in other forms of the present technology, air can be taken to mean some other combination of breathable gases, for example atmospheric air enriched with oxygen.

[0254] Environment: In certain forms of the technology, the term environment can have the following meanings (i) external to the therapy system or patient, and (ii) directly surrounding the therapy system or patient.

[0255] For example, relative to the environment of the humidifier Humidity may be the humidity of the air directly surrounding the humidifier, for example the humidity in the room in which the patient is sleeping. This ambient humidity can be different to the humidity outside the room in which the patient is sleeping.

[0256] In another example, the ambient pressure can be the pressure directly surrounding or external to the body.

[0257] In certain forms, the ambient (e.g. acoustic) noise can be considered to be the background noise level in the room in which the patient is located, other than for example noise generated by the RPT device or from the mask or patient interface. Ambient noise can be generated by sound sources external to the room.

[0258] Auto-Positive Airway Pressure (APAP) therapy: CPAP therapy in which the therapy pressure is automatically adjustable between a minimum and a maximum, for example differing with each breath, depending on whether or not there is an indication of an SBD event.

[0259] Continuous Positive Airway Pressure (CPAP) therapy: respiratory pressure therapy in which the therapy pressure can be approximately constant throughout the respiratory cycle of the patient. In some forms, the pressure at the entrance to the airways will be slightly higher during exhalation and slightly lower during inhalation. In some forms, the pressure will vary between different respiratory cycles of the patient, for example increasing in response to detecting an indication of partial airway obstruction, and decreasing in the absence of an indication of partial airway obstruction.

[0260] Flow: Volume (or mass) of air delivered per unit of time. Flow can refer to an instantaneous quantity. In some cases, reference to flow will be reference to a scalar quantity, i.e. a quantity having only magnitude. In other cases, reference to flow will be reference to a vector quantity, i.e. a quantity having both magnitude and direction. Flow can be given the symbol Q. ‘Flow’ is sometimes simply abbreviated to ‘flow’ or ‘air flow’.

[0261] In the example of a patient breathing, the flow can be nominally positive for the inhalation portion of the patient’s respiratory cycle, and thus negative for the exhalation portion of the patient’s respiratory cycle. The total flow (Qt) is the flow of air out of the RPT device. The ventilation flow (Qv) is the flow of air out of the exhaust to allow washout of exhaled gases. The leak flow (Ql) is the flow of leaks from the patient interface system or elsewhere. The respiratory flow (Qr) is the flow of air received into the patient’s respiratory system.

[0262] Humidifier: Humidifier is taken to mean a humidification device constructed and arranged, or configured with a physical structure, to be able to provide a therapeutic beneficial amount of water (H2O) vapour to an air flow to improve a patient's medical respiratory condition.

[0263] Leak: The word leak is taken to mean an unwanted flow of air. In one example, a leak can occur due to an imperfect seal between the mask and the patient's face. In another example, a leak can occur in a swivel elbow to ambient.

[0264] Noise, conducted (acoustic): Conducted noise herein refers to 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.

[0265] Noise, radiated (acoustic): Radiated noise herein refers to noise brought to the patient through the surrounding 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.

[0266] Noise, ventilatory (acoustic): Ventilatory noise herein refers to noise produced by the air flow through any exhaust port, for example in a patient interface.

[0267] Patient: A human, whether or not they suffer from a respiratory disease.

[0268] Pressure: Force per unit area. Pressure can be measured in units including cmH2O, g-f / cm 2 and hectopascals. 1 cmH2O is equal to 1 g-f / cm 2 and is approximately 0.98 hectopascals. In this specification, pressure is given in units of cmH2O unless otherwise stated.

[0269] Pressure in the patient interface is given the symbol Pm, while the treatment pressure is given the symbol Pt, which represents the target value achieved by the mask pressure Pm at the current instant in time.

[0270] Respiratory Pressure Therapy (RPT): The application of a supply of air at a treatment pressure, which is typically positive with respect to atmospheric pressure, to the entrance of the airways.

[0271] Ventilator: A mechanical device that provides pressure support to a patient to perform some or all of the work of breathing.

[0272] 5.7.1.1 Materials

[0273] Silicone or silicone elastomer: A synthetic rubber. In this specification, reference to silicone means liquid silicone rubber (LSR) or compression molded silicone rubber (CMSR). One form of commercially available LSR is SILASTIC (including the range of products sold under this trademark) manufactured by Dow Corning. Another manufacturer of LSR is Wacker. Unless specified to the contrary, an exemplary form of LSR has a Shore A (or Type A) indentation hardness in the range of about 35 to about 45 as measured using ASTM D2240.

[0274] Polycarbonate: A thermoplastic polymer of bisphenol A carbonate.

[0275] 5.7.1.2 Mechanical properties

[0276] Resilience: The ability of a material to absorb energy when elastically deformed and to release energy when unloaded.

[0277] ‘Resilient’: Will substantially release all energy when unloaded. Includes some silicones and thermoplastic elastomers.

[0278] Hardness: The ability of a material to resist deformation by itself (e.g. as described by Young’s modulus, or indentation hardness scales measured on standard sample sizes).

[0279] • ‘Soft’ materials can include silicones or thermoplastic elastomers (TPEs) and can deform easily, for example under finger pressure.

[0280] • ‘Hard’ materials can include polycarbonates, polypropylene, steel or aluminium and can not deform easily, for example under finger pressure.

[0281] Hardness (or stiffness) of a structure or assembly: The ability of a structure or assembly to resist deformation in response to an applied load. The load can be a force or a moment, for example compression, tension, bending or torsion. A structure or assembly can provide different resistance to deformation in different directions.

[0282] ‘Floppy’ structure or assembly: A structure or assembly that will change shape, for example bend, when left to support its own weight over a relatively short period of time, such as 1 second.

[0283] ‘Rigid’ structure or assembly: A structure or assembly that will not substantially change shape when subjected to loads typically encountered in use. One example of such use can be to set up and maintain a patient interface in a sealing relation with an entrance to a patient’s airways, for example under a load of about 20 to 30 cmH20 pressure.

[0284] As an example, an I-beam can comprise a different bending stiffness (resistance to bending loads) in a first direction compared to a second, orthogonal direction. In another example, a structure or component is floppy in a first direction and rigid in a second direction.

[0285] 5.7.2 Patient interface

[0286] Anti-asphyxia valve (AAV): A component or subassembly of a mask system that reduces the risk of excessive C02 rebreathing by the patient by venting to atmosphere in a failsafe manner.

[0287] Elbow: An elbow is an example of a structure that directs the axis of airflow passing therethrough to change direction by an angle. In one form, the angle can be about 90 degrees. In another form, the angle can be greater or less than 90 degrees. An elbow can have a cross-section that is approximately circular. In another form, an elbow can have an elliptical or rectangular cross-section. In certain forms, an elbow can be rotatable relative to a mating component, for example, about 360 degrees. In certain forms, an elbow can be removable from a mating component, for example, by a snap connection. In certain forms, an elbow can be assembled to a mating component by a disposable snap during manufacture, but not removable by a patient.

[0288] Frame: A frame will be taken to mean a mask structure that carries the tensile load between two or more connection points with headgear. A mask frame can be a non-airtight load bearing structure in a mask. However, some forms of mask frame can also be airtight.

[0289] Headgear: Headgear will be taken to mean a form of positioning and stabilising structure designed for use on the head. For example, headgear comprises a collection of one or more support straps, tie straps and stiffening rods configured to position and hold a patient interface in place on the patient's face for delivery of respiratory therapy. Some tie straps are formed from soft, pliable, elastic material, such as a laminate of foam and fabric.

[0290] Membrane: A membrane will be taken to mean a typically thin element that is preferably substantially inextensible but not substantially resistant to bending.

[0291] Plenum chamber: A mask plenum chamber will be taken to mean a portion of a patient interface having walls that at least partially enclose a volume of space that in use has air pressurised therein that exceeds atmospheric pressure. A housing can form part of a wall of a mask plenum chamber.

[0292] Seal: Can be in the form of a noun ("seal") which refers to a structure, or a verb ("seal") which refers to an effect. Two elements can be structured and / or arranged to "seal" or achieve a "seal" therebetween without the need for a separate "seal" element per se.

[0293] Shell: A shell will be considered to mean a curved and relatively thin structure with bendable, stretchable, and compressible stiffness. For example, a curved structural wall of a face mask can be a shell. In some forms, the shell can be multi-faceted. In some forms, the shell can be air-tight. In some forms, the shell can not be air-tight.

[0294] Reinforcement: A reinforcement will be considered to mean a structural component designed to increase the bending resistance of another component in at least one direction.

[0295] Support: A support will be considered to mean a structural component designed to increase the compressive resistance of another component in at least one direction.

[0296] Swivel (noun): A subcomponent of an assembly configured to rotate about a common axis, preferably independently, preferably at low torque. In one form, a swivel can be configured to rotate through an angle of at least 360 degrees. In another form, a 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 subcomponent of the assembly preferably comprises a pair of mating cylindrical conduits. There can be little or no air leakage from the swivel in use.

[0297] Tie (noun): A structure designed to resist tension.

[0298] Exhaust port: (noun): A structure that allows air to flow from inside a mask or conduit to ambient air for clinically effective flushing of exhaled gases. For example, a clinically effective flush can include a flow rate of about 10 liters / minute to about 100 liters / minute, depending on the mask design and treatment pressure.

[0299] 5.7.3 Structure Shape

[0300] A product according to the present technology can include one or more three-dimensional mechanical structures, such as a face mask cushion or a prong. Three-dimensional structures can be joined by two-dimensional surfaces. These surfaces can be distinguished using labels to describe the relevant surface orientation, location, function, or some other characteristic. For example, a structure can include one or more of an anterior surface, a posterior surface, an inner surface, and an outer surface. In another example, a seal-forming structure can include a (e.g., external) surface that contacts the face and a separate (e.g., underside or internal) surface that does not contact the face. In another example, a structure can include a first surface and a second surface.

[0301] To aid in describing the shape of three-dimensional structures and surfaces, first consider a cross-section through a point p of a surface. See Figures 3B to 3F , which show examples of cross-sections at a point p on a surface and the resulting planar profile. Figures 3B to 3FThe outward normal vector at point p is also shown. The outward normal vector at point p is away from the surface. In some instances, the surface is described from the viewpoint of an imaginary little person standing upright on the surface.

[0302] 5.7.3.1 Curvature in one dimension

[0303] The curvature of a plane curve at p can be described with a sign (e.g., positive, negative) and a quantity (e.g., the reciprocal of the radius of the circle that only touches the curve at p).

[0304] Positive curvature: If the curve at point p turns outward toward the normal, then the curvature at that point will be positive (if the figures in the image were to leave point p, they would have to walk uphill). See also Figure 3B (and Figure 3C Compared to relatively large positive curvature) and Figure 3C (and Figure 3B (Compared to relatively small positive curvature). Such curves are often referred to as concave surfaces.

[0305] Zero curvature: If the curve at point p is a straight line, then the curvature will be zero (if you imagine a little person leaving point p, they can walk horizontally without going up or down). See also Figure 3D .

[0306] Negative curvature: If the curve at point p deviates from the outward normal, then the curvature in that direction at that point will be negative (if you imagine little figures leaving point p, they must go downhill). See also Figure 3E (and Figure 3F Compared to relatively small negative curvature) and Figure 3F (and Figure 3E (Compared to relatively large negative curvature). Such curves are often referred to as convex surfaces.

[0307] 5.7.3.2 Curvature of Two-Dimensional Surfaces

[0308] A description of the shape at a given point on a two-dimensional surface according to the present technology may include multiple normal cross sections. These cross sections may cut through the surface in a plane including an outward normal (“normal plane”), and each cross section may be cut in a different direction. Each cross section produces a planar curve with a corresponding curvature. The different curvatures at that point may have the same sign or different signs. Each curvature at that point has a quantity, for example, a relatively small quantity. Figures 3B to 3F A planar curve in a plane can be an instance of multiple cross-sections at a specific point.

[0309] Principal curvature and principal direction: The direction of the normal plane to which the curvature of the curve reaches its maximum and minimum values ​​is called the principal direction. Figures 3B to 3F In the example, the maximum curvature occurs Figure 3BThe minimum occurs at p = 0.5 Figure 3F Thus Figure 3B and Figure 3F is the cross-section in the principal direction. The principal curvature at p is the curvature in the principal direction.

[0310] Region of a surface: a set of points connected on a surface. The set of points in a region can have similar characteristics, e.g. curvature or sign.

[0311] Saddle region: a region in which the principal curvatures have opposite signs at each point, i.e. one sign is positive and the other sign is negative (according to the direction in which an imagined individual turns, they can walk up or down).

[0312] Dome region: a region in which the principal curvatures have the same sign at each point, e.g. both positive (“concave dome”) or both negative (“convex dome”).

[0313] Cylindrical region: a region in which one principal curvature is zero (or, e.g. within manufacturing tolerances, zero) and the other principal curvature is non-zero.

[0314] Planar region: a region of a surface in which both principal curvatures are zero (or, e.g. within manufacturing tolerances, zero).

[0315] Edge of a surface: the boundary or limit of a surface or region.

[0316] Path: in certain forms of the technology, a ‘path’ will mean a path in the mathematical-topological sense, e.g. a continuous space curve on a surface from f(0) to f(l). In certain forms of the technology, a ‘path’ can be described as a route or course, including e.g. a set of points on a surface. (An imagined individual’s path is a path in which they walk on the surface and is analogous to a garden path).

[0317] Path length: in certain forms of the technology, a ‘path length’ will be the distance along a surface from f(0) to f(l), i.e. the distance along a path on a surface. There can be more than one path between two points on a surface and such paths can have different path lengths. (An imagined individual’s path length will be the distance they walk along a path on a surface).

[0318] Straight-line distance: the straight-line distance is the distance between two points on a surface, but without regard to the surface. In a planar region, there can be a path on the surface with the same path length as the straight-line distance between two points on the surface. In a non-planar surface, there can not be a path with the same path length as the straight-line distance between two points. (For an imagined individual, the straight-line distance will correspond to the distance as a ‘straight line’).

[0319] 5.7.3.3 Space Curve

[0320] Space Curve: Unlike a planar curve, a space curve does not have to lie in any particular plane. A space curve can be closed, i.e., have no endpoints. A space curve can be thought of as one dimension in three-dimensional space. An imaginary person walking on a DNA helix strand walks along a space curve. A typical human left ear includes a helix, which is a left-handed helix, see Figure 3Q . A typical human right ear includes a helix, which is a right-handed helix, see Figure 3R . Figure 3S A right-handed helix is shown. The edges of a structure, e.g., a membrane or a pusher, can follow a space curve. In general, a space curve can be described by the curvature and torsion at each point on the space curve. Torsion is a measure of how much a curve deviates from a plane. Torsion has a sign and a magnitude. Torsion at a point on a space curve can be characterized with reference to the tangent, normal, and binormal vectors at that point.

[0321] Tangent Unit Vector (or Unit Tangent Vector): For each point on a curve, the vector at that point indicates the direction and magnitude from that point. The tangent unit vector is a unit vector pointed in the same direction as the curve at that point. If an imaginary person were to fly along the curve and stop at a particular point, the direction of the tangent vector is the direction it would be heading.

[0322] Unit Normal Vector: As the imaginary person moves along the curve, this tangent vector itself changes. The unit vector pointed in the same direction that the tangent vector is changing is called the unit principal normal vector. It is perpendicular to the tangent vector.

[0323] Binormal Unit Vector: The binormal unit vector is perpendicular to the tangent vector and the principal normal vector. Its direction can be determined by the right-hand rule (see, e.g., Figure 3P ) or, alternatively, by the left-hand rule ( Figure 3O ).

[0324] Osculating Plane: The plane containing the unit tangent vector and the unit principal normal vector. See Figure 3O and Figure 3P .

[0325] Torsion of a Space Curve: The torsion at a point on a space curve is the rate of change of the binormal vector at that point. It measures how much the curve deviates from the osculating plane. A space curve lying in a plane has zero torsion. A space curve that deviates relatively little from the osculating plane will have a relatively small magnitude of torsion (e.g., a slightly tilted helical path). A space curve that deviates relatively much from the osculating plane will have a relatively large magnitude of torsion (e.g., a sharply tilted helical path). See Figure 3S , although T2> T1, at Figure 3Sthe number of twists near the top spiral of Figure 3S the bottom spiral of

[0326] Referring to Figure 3P the right-hand rule, a spatial curve that turns in the direction of the right-hand binormal can be considered to have right-handed positive twist (e.g., as in a right-handed helix as shown in Figure 3S A spatial curve that deviates away from the direction of the right-hand binormal can be considered to have right-handed negative twist (e.g., a left-handed helix).

[0327] Also and referring to the left-hand rule (see Figure 3O ), a spatial curve that turns in the direction of the left-hand binormal can be considered to have left-handed positive twist (e.g., a left-handed helix). Thus, left-handed positive twist is equivalent to right-handed negative twist. See Figure 3T .

[0328] 5.7.3.4 Holes

[0329] A surface can have one-dimensional holes, e.g., holes defined by planar curves or by spatial curves. A thin structure (e.g., a membrane) having holes can be described as having one-dimensional holes. For example, see the one-dimensional holes in the structure surface shown in Figure 3I which are defined by planar curves.

[0330] A structure can have two-dimensional holes, e.g., holes defined by a surface. For example, an inflatable tire has a two-dimensional hole defined by the inner surface of the tire. In another example, a bladder having a cavity for air or gel has a two-dimensional hole. For example, see the mattress of Figure 3L and the exemplary cross-sections therethrough in Figure 3M and Figure 3N which the inner surface defines a specified two-dimensional hole. In yet another example, a catheter can include one-dimensional holes (e.g., at its inlet or at its outlet) and a two-dimensional hole defined by the inner surface of the catheter. See also the two-dimensional hole of the structure shown in Figure 3K which is defined by the shown surface.

[0331] 5.8 Other Notes

[0332] A portion of the disclosure of this patent document contains material that 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 and Trademark Office patent file or records, but otherwise reserves all copyright rights whatsoever.

[0333] Unless otherwise stated in the context, and where a range of values is provided, it is to be understood that each intervening value, to the tenth of the unit of the lower limit unless the context clearly dictates otherwise, and any other stated or intervening value in that stated range is encompassed within the application technology. The upper and lower limits of these intervening ranges can independently be included in the smaller ranges, and are also encompassed within the application technology, subject to any specifically excluded limit in the stated range. Where the stated range includes one or both of the limits, ranges excluding either or both of the included limits are also included in the application technology.

[0334] Furthermore, where a range of values is recited as a part of the application technology, it is to be understood that such a recitation is merely an approximation, and that the actual values used in the actual technology implementation can be different, as the technology implementation can require or permit variations within the stated range.

[0335] Unless defined otherwise, 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 application technology belongs. Although any methods and materials similar or equivalent to those described herein can be used in the practice or testing of the present application technology, a limited number of the exemplary methods and materials are described herein.

[0336] When a particular material is named for use in constructing a component, obvious alternative materials of similar properties are considered as substitutes therefor. In addition, unless otherwise specified, any and all components described herein are understood to be capable of being manufactured and thus can be manufactured together or separately.

[0337] It must be noted that, as used herein and in the appended claims, the singular form "a", "an", and "the" include plural references unless the context clearly dictates otherwise.

[0338] All publications mentioned herein are incorporated by reference to disclose and describe the methods and / or materials in connection with which the publications are cited. The publications discussed herein are provided solely for their disclosure prior to the filing date of the present application. Nothing herein is to be construed as an admission that the present application technology is not entitled to antedate such publication by virtue of prior application. Further, the dates of publication provided can be different from the dates that can appear on the publications that were published by the U.S. Patent and Trademark Office.

[0339] The terms "comprising" and "including" should be interpreted as specifying the presence of the stated elements, components, or steps, but not precluding the presence of one or more other elements, components, or steps, or groups thereof.

[0340] The main headings used in the detailed description are included for ease of reference only and shall not be construed as limiting the subject matter found in the entire disclosure or the claims. The subject headings shall not be used to construe the scope of the claims or the claims limitations.

[0341] While the present technology has been described with reference to specific examples, it will be appreciated that the description is illustrative of the inventive principles and applications. In some instances, specialized terminology and notation can imply specific details not required to practice the present technology. For example, while the terms "first" and "second" can be used, they are not intended to indicate any order unless specified, but can be used to distinguish different elements. Additionally, while process steps in a method can be described or illustrated in a certain order, this order is not required. Those skilled in the art will recognize that the order can be modified and / or aspects can be performed at the same time or even simultaneously.

[0342] Thus, it will be appreciated that numerous modifications can be made to the illustrative examples and that other arrangements can be devised without departing from the spirit and scope of the present technology.

[0343] 5.9 List of Reference Symbols

[0344]

[0345]

Claims

1. A water reservoir for a device for generating and humidifying a breathable gas stream, the water reservoir being configured to be removably received by a water reservoir base of the device, the water reservoir base including a heater plate, the water reservoir comprising: A reservoir base, the reservoir base including a bottom wall and side walls forming a cavity, the cavity being configured to contain a certain volume of liquid; as well as A thin film disposed on the reservoir base, at least a portion of which is configured to thermally engage with the heater plate when the water reservoir is removably received by the water reservoir base of the device, to allow heat transfer from the heater plate to the volume of liquid during use. The thin film includes: a. A first side surface, comprising at least a portion of the bottom inner surface of the water reservoir exposed to the volume of liquid, and b. The second side, which is opposite to the first side. The second side of the film includes at least a portion of an exposed bottom outer surface of the water reservoir that is exposed to the heater plate, configured to form the water reservoir, to allow thermal bonding with the heater plate when the water reservoir is removably received by the water reservoir base. The film mentioned above comprises an elastomeric material. At least a portion of the bottom wall and side wall of the reservoir base forms the inner surface of the water reservoir exposed to the volume of liquid. The bottom wall of the reservoir base includes a hole, and the film is fixed to the bottom wall such that the film seals and covers the hole, and the peripheral edge of the film extends beyond the edge of the hole such that the film overlaps with at least a portion of the inner surface of the bottom wall.

2. The water reservoir of claim 1, wherein the film comprises one or more additives to enhance thermal conductivity.

3. The water storage device according to claim 2, wherein the membrane comprises ceramic powder additives and / or metal powder additives.

4. The water storage device according to claim 1, wherein the membrane comprises multiple layers.

5. The water storage device according to claim 4, wherein the film comprises a metal layer and a plastic layer on one or both sides of the metal layer.

6. The water reservoir of claim 1, wherein the thin film comprises a coating of thermally conductive material applied to one side of the thin film.

7. The water reservoir of claim 6, wherein the coating of the thermally conductive material is applied to the second side of the thin film.

8. The water reservoir of claim 1, further comprising one or more ribs configured to extend through the membrane to generate a force configured to push the membrane toward the heater plate when the water reservoir is removably received by the water reservoir base.

9. The water storage device according to claim 1, wherein the wall thickness of the membrane is less than 0.5 mm.

10. The water reservoir of claim 1, wherein the membrane comprises silicone resin.

11. The water reservoir of claim 1, wherein the peripheral edge of the film extends to one or more sidewalls of the reservoir base such that the film overlaps with at least a portion of the inner surface of one or more sidewalls of the reservoir base.

12. The water reservoir according to claim 1, wherein the wall thickness of the membrane is less than the wall thickness of the bottom wall and the side wall of the reservoir base.

13. The water reservoir of claim 1, wherein the membrane is configured to be separate from and different from the base of the water reservoir.

14. The water reservoir of claim 1, wherein the membrane comprises a preformed structure, the preformed structure being fixed to the reservoir base.

15. The water reservoir of claim 1, wherein the membrane is planar.

16. The water reservoir of claim 1, wherein the second side of the film provides a contact surface configured to engage directly with the heater plate when the water reservoir is removably received by the water reservoir base.

17. The water reservoir of claim 1, further comprising a reservoir cover movably connected to the reservoir base to allow the water reservoir to switch between an open configuration and a closed configuration.

18. An apparatus for humidifying a breathable gas stream, comprising: Water storage tank base; as well as The water reservoir according to any one of claims 1 to 17 is disposed on the base of the water reservoir.

19. The device of claim 18, wherein the water reservoir base forms a cavity for at least partially accommodating the water reservoir.

20. The device of claim 18, wherein the water reservoir base includes the heater plate, the heater plate being configured to thermally bond with the thin film disposed on the water reservoir.

Images