Breathable gas flow generator with silencing device

Abstract

The present technology relates to an apparatus for generating a flow of gas, the apparatus comprising: a housing having an inlet and an outlet; a blower comprising a motor and an impeller to draw ambient gas into the housing through the inlet and expel the housing through the outlet; and at least one sound attenuation device lined on one or more surfaces of the housing and / or the blower. Further, a sound attenuation device is disclosed, the sound attenuation device comprising a nonwoven fabric configured to absorb sound waves for reducing noise in an apparatus for supplying a flow of breathable gas at positive pressure for respiratory therapy.

Description

Technical Field

[0001] This technology relates to one or more of the screening, diagnosis, monitoring, treatment, prevention and improvement of respiratory-related disorders.

[0002] This technology also relates to medical or household devices or equipment and their uses. Background Technology

[0003] 1.2.1 The Human Respiratory System and Its Disorders

[0004] The human respiratory system facilitates gas exchange. The nose and mouth form the entrances to the patient's airway.

[0005] The airways consist of a series of branching tracheae, which become narrower, shorter, and more numerous as they penetrate deeper into the lungs. The primary function of the lungs is gas exchange, allowing oxygen to move from inhaled air into the venous blood and allowing carbon dioxide to move in the opposite direction. The trachea divides into the left and right main bronchioles, which eventually further divide into terminal bronchioles. The bronchi form the conduction airways and do not participate in gas exchange. Further branches of the airways lead to the respiratory bronchioles and eventually to the alveoli. The alveolar regions of the lungs are where gas exchange occurs and are called the respiratory regions. See John B. West's *Physiology of Respiratory Systems*, published in 2012 by Lippincott Williams & Wilkins. Respiratory Physiology 9th edition of "The 9th Edition ...

[0006] A range of breathing disorders exist. Some disorders may be characterized by specific events, such as apnea, hypoventilation, and hyperventilation.

[0007] Examples of breathing disorders include obstructive sleep apnea (OSA), Cheyne-Stokes respiration (CSR), respiratory insufficiency, obesity-hypopnea syndrome (OHS), chronic obstructive pulmonary disease (COPD), neuromuscular disease (NMD), and chest wall disorders.

[0008] 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 areas of the tongue, soft palate, and posterior oropharyngeal walls during sleep. The condition causes affected patients to stop breathing, typically for periods ranging from 30 to 120 seconds, sometimes up to 200 to 300 times per night. This often leads to excessive daytime sleepiness and can potentially cause cardiovascular disease and brain damage. The syndrome is a common disorder, particularly among middle-aged overweight men, but those affected may not be aware of the problem, see, for example, U.S. Patent No. 4,944,310 (Sullivan).

[0009] Cheyne-Stokes respiration (CSR) is another form of sleep-disordered breathing. CSR is an impairment of the patient's respiratory controller, characterized by rhythmic alternations of waxing and waning ventilation known as the CSR cycle. CSR is characterized by repeated deoxygenation and reoxygenation of arterial blood. CSR can be harmful due to repetitive hypoxia. In some patients, CSR is associated with recurrent awakenings from sleep, leading to severe sleep disruption, increased sympathetic activity, and increased afterload, see, for example, U.S. Patent No. 6,532,959 (Berthon-Jones).

[0010] 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 cover some or all of the following disorders.

[0011] Patients with respiratory insufficiency (a form of respiratory failure) may experience abnormal shortness of breath during exercise.

[0012] Obesity-hypopnea syndrome (OHS) is defined as a combination of severe obesity and chronic hypercapnia at wakefulness, without other known causes of hypoventilation. Symptoms include dyspnea, morning headache, and excessive daytime sleepiness.

[0013] Chronic obstructive pulmonary disease (COPD) encompasses any of a group of lower airway diseases that share certain common characteristics. These characteristics include increased air resistance, prolonged expiratory phase of breathing, and loss of normal lung elasticity. Examples of COPD include emphysema and chronic bronchitis. COPD is caused by chronic smoking (a major risk factor), occupational exposure, air pollution, and genetic factors. Symptoms include exertional dyspnea, chronic cough, and sputum production.

[0014] Neuromuscular disease (NMD) is a broad term encompassing many conditions and ailments that impair muscle function directly through intrinsic muscle pathology or indirectly through neuropathology. Some NMD patients are characterized by progressive muscle damage that leads to loss of mobility, wheelchair use, dysphagia, respiratory muscle weakness, and ultimately death from respiratory failure. Neuromuscular disorders can be classified as rapidly progressive or slowly progressive: (i) rapidly progressive disorders: characterized by muscle damage that worsens over months and leads to death within years (e.g., amyotrophic lateral sclerosis (ALS) and Duchenne muscular dystrophy (DMD) in adolescents); (ii) variable or slowly progressive disorders: characterized by muscle damage that worsens over years and only slightly shortens life expectancy (e.g., limb-girdle type, facioscapulohumeral type, and ankylosing spondylitis). Symptoms of respiratory failure in NMD include: progressive general weakness, dysphagia, shortness of breath during and at rest, fatigue, somnolence, morning headache, difficulty concentrating, and mood swings.

[0015] Chest wall disorders are a group of chest wall deformities that result in inefficient connection between the respiratory muscles and the thoracic cavity. These disorders are typically characterized by restrictive defects and have the potential to cause chronic hypercapnia-related respiratory failure. Scoliosis and / or kyphosis can cause severe respiratory failure. Symptoms of respiratory failure include: dyspnea during exercise, peripheral edema, orthopnea, recurrent chest infections, morning headache, fatigue, poor sleep quality, and loss of appetite.

[0016] A range of therapies have been used to treat or improve these conditions. Furthermore, other healthy individuals can utilize these therapies to prevent respiratory distress. However, these have many drawbacks.

[0017] 1.2.2 Therapy

[0018] Various respiratory therapies, such as continuous positive airway pressure (CPAP), non-invasive ventilation (NIV), invasive ventilation (IV), and high-flow therapy (HFT), have been used to treat one or more of the aforementioned respiratory disorders.

[0019] 1.2.2.1 Respiratory pressure therapy

[0020] Respiratory pressure therapy is the application of supplying air to the inlet of the airway at a controlled target pressure that is nominally positive relative to the atmosphere throughout the patient’s respiratory cycle (as opposed to negative pressure therapy such as canister ventilators or chest tubes).

[0021] Continuous positive airway pressure (CPAP) therapy has been used to treat obstructive sleep apnea (OSA). Its mechanism of action is that CPAP acts as a pneumatic splint and can prevent upper airway obstruction, such as by pushing the soft palate and tongue forward and away from the posterior oropharyngeal wall. Treatment for OSA with CPAP can be voluntary, and therefore patients may choose not to adhere to the therapy if they find the device used to provide such treatment uncomfortable, difficult to use, expensive, or unsightly.

[0022] Noninvasive ventilation (NIV) provides ventilatory support to patients through the upper airway to help them breathe and / or maintain adequate oxygen levels in the body by performing some or all of the work of breathing. Ventilatory support is delivered via a noninvasive patient interface. NIV has been used to treat chronic respiratory failure (CSR) as well as forms of respiratory failure such as OHS, COPD, NMD, and chest wall disorders. In some forms, the comfort and effectiveness of these therapies can be improved.

[0023] Invasive ventilation (IV) provides ventilatory support to patients who are no longer able to breathe effectively on their own and can be delivered using a tracheostomy tube or endotracheal tube. In some forms, the comfort and effectiveness of these therapies can be improved.

[0024] 1.2.2.2 Flow Therapy

[0025] Not all respiratory therapies are designed to deliver a prescribed therapeutic pressure. Some respiratory therapies are designed to deliver a prescribed volume of air by delivering an inspiratory flow profile (possibly superimposed on a positive baseline pressure) over a target duration. In others, the interface to the patient's airway is "open" (unsealed), and the respiratory therapy may supplement only the patient's own spontaneous breathing with a regulated or enriched flow of gas. In one example, high-flow therapy (HFT) delivers a continuous, heated, humidified flow of air to the airway inlet through an unsealed or open patient interface at a "therapeutic flow rate" that remains substantially constant throughout the respiratory cycle. This therapeutic flow rate is nominally set to exceed the patient's peak inspiratory flow rate. HFT has been used to treat OSA, CSR, respiratory failure, COPD, and other respiratory disorders. One mechanism of action is that the high flow rate of air at the airway inlet improves ventilation efficiency by flushing or washing out exhaled CO2 from the patient's anatomical dead space. Therefore, HFT is sometimes referred to as dead space therapy (DST). Other benefits may include increased warmth and humidification (which may be beneficial in secretion management) and the possibility of appropriately increasing airway pressure. As an alternative to constant flow, the therapeutic flow can follow a curve that varies with the respiratory cycle.

[0026] Another form of flow therapy is long-term oxygen therapy (LTOT), or supplemental oxygen therapy. Doctors can prescribe a continuous flow of oxygen-enriched air to the patient's airway at a specified oxygen concentration (the oxygen fraction in ambient air, 21% to 100%) and a specified flow rate (e.g., 1 liter per minute (LPM), 2 LPM, 3 LPM, etc.).

[0027] 1.2.3 Respiratory Therapy System

[0028] These respiratory therapies can be provided by respiratory therapy systems or devices. Such systems and devices can also be used to screen, diagnose, or monitor conditions without treating them.

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

[0030] 1.2.3.1 Patient Interface

[0031] Patient interfaces can be used to interface breathing equipment with its wearer, for example, by providing an airflow into the airway inlet. The airflow can be provided to the patient's nose and / or mouth via a mask, to the patient's mouth via a tube, or to the patient's trachea via a tracheostomy tube. Depending on the therapy to be administered, the patient interface can form a seal with an area such as the patient's face to facilitate the delivery of gas at a pressure sufficiently different from ambient pressure (e.g., a positive pressure of about 10 cmH2O relative to ambient pressure). For other forms of therapy, such as oxygen delivery, the patient interface may not include a seal sufficient to facilitate the delivery of a gas supply to the airway at a positive pressure of about 10 cmH2O. For flow-through therapies such as nasal HFT, the patient interface is configured to blow air into the nostrils, but specifically avoids a complete seal. An example of such a patient interface is a nasal cannula.

[0032] 1.2.3.2 Respiratory Pressure Therapy (RPT) Device

[0033] Respiratory pressure therapy (RPT) devices can be used alone or as part of a system to deliver one or more of the various therapies described above, such as by operating the device to generate an airflow for delivery to an interface in the airway. The airflow can be pressure-controlled (for respiratory pressure therapy) or flow-controlled (for flow-based therapies such as HFT). Therefore, an RPT device can also function as a flow-based therapy device. Examples of RPT devices include CPAP devices and ventilators.

[0034] Pneumatic generators are known in a variety of applications, such as industrial-scale ventilation systems. However, pneumatic generators for medical applications have specific requirements that more general-purpose pneumatic generators cannot meet, such as the reliability, size, and weight requirements of medical devices. Furthermore, even devices designed for medical use may have disadvantages related to one or more of the following: comfort, noise, ease of use, efficiency, size, weight, manufacturability, cost, and reliability.

[0035] One example of the special requirements for certain RPT devices is acoustic noise.

[0036] Noise output level table for existing RPT devices (only one specimen, measured in CPAP mode at 10 cmH2O using the test method specified in ISO 3744).

[0037]

[0038] One known RPT device for treating sleep-disordered breathing is the S9 Sleep Therapy System manufactured by ResMed Inc. Another example of an RPT device is a ventilator. Ventilators, such as the ResMed Stellar™ series of adult and pediatric ventilators, provide invasive and non-invasive non-dependent ventilatory support to a range of patients for the treatment of various conditions, including but not limited to NMD, OHS, and COPD.

[0039] The ResMed Elisée™ 150 and ResMed VS III™ ventilators support invasive and non-invasive ventilation for adult and pediatric patients in the treatment of a variety of conditions. These ventilators offer volume ventilation and pressure ventilation modes with single-limb or dual-limb circuits. RPT devices typically include a pressure generator, such as a motor-driven blower or compressed gas reservoir, and are configured to supply airflow to the patient's airway. In some cases, the airflow may be supplied to the patient's airway at positive pressure. The RPT device outlet is connected to the patient interface, such as those described above, via an air circuit.

[0040] Some known RPT devices use foam components at various locations within the RPT unit to reduce noise during system operation. However, due to the manufacturing methods required to produce the foam, the structure and composition of the foam may vary. This can lead to assembly difficulties.

[0041] The flexible nature of foam components also limits the strength and formability of any component made from foam materials.

[0042] Device designers may face an endless array of choices. Design standards often conflict, meaning some design choices are either unconventional or unavoidable. Furthermore, aspects of comfort and efficiency can be highly sensitive to minute variations in one or more parameters.

[0043] 1.2.3.3 Air Circuit

[0044] An air circuit is a conduit or tube constructed and arranged to allow airflow between two components of a respiratory therapy system (such as the RPT device and the patient interface) during use. In some cases, there may be separate branches of the air circuit for inhalation and exhalation. In other cases, a single-branch air circuit is used for both inhalation and exhalation.

[0045] 1.2.3.4 Humidifier

[0046] Delivering airflow without humidification can lead to airway dryness. Using a humidifier with an RPT device and patient interface generates humidified gas, which minimizes nasal mucosal dryness and increases patient airway comfort. Additionally, in colder climates, warm air applied to the patient interface and surrounding facial area is generally more comfortable than cold air.

[0047] 1.2.3.5 Data Management

[0048] There may be clinical reasons for obtaining data to determine whether a patient receiving respiratory therapy is "adherent," such as the patient having used their RPT device according to one or more "adherence rules." An example of an adherence rule for CPAP therapy is that, in order to be considered adherent, the patient is required to use the RPT device for at least four hours each night for at least 21 out of 30 consecutive days. To determine patient adherence, the RPT device provider (such as a healthcare provider) may manually obtain data describing the patient's use of the RPT device for treatment, calculate usage over the predetermined time period, and compare it to the adherence rules. Once the healthcare provider has determined that the patient has used their RPT device according to the adherence rules, the healthcare provider may notify a third party that the patient is adherent.

[0049] The patient's treatment may benefit from other aspects of communicating treatment data to third parties or external systems.

[0050] Existing processes for communicating and managing this type of data may suffer from one or more of the following problems: expensive, time-consuming, and error-prone. Summary of the Invention

[0051] This technology aims to provide a gas flow generating device that includes a silencing device that provides one or more of the following: improved auditory characteristics, ease of manufacture, cost, or effectiveness.

[0052] This technology aims to provide medical devices for screening, diagnosing, monitoring, improving, treating or preventing respiratory disorders, which have one or more of the following: improved comfort, cost, efficacy, ease of use and manufacturability.

[0053] The first aspect of this technology relates to a gas flow generation device with improved noise reduction capabilities.

[0054] On the other hand, it relates to a silencing device suitable for equipment used to generate gas flows.

[0055] Another aspect of this technology relates to devices for screening, diagnosing, monitoring, improving, treating, or preventing respiratory disorders.

[0056] Another aspect of this technology relates to methods for screening, diagnosing, monitoring, improving, treating, or preventing respiratory disorders.

[0057] One aspect of certain forms of this technology is to provide methods and / or devices for improving patient adherence to respiratory therapy.

[0058] One form of this technology includes a positioning and stabilizing structure configured to provide force to hold the seal-forming structure in a therapeutically effective position on the patient's head. The positioning and stabilizing structure includes at least one strap.

[0059] One form of this technology includes a patient interface comprising an inflation chamber, a sealing formation structure, and a positioning and stabilizing structure.

[0060] One form of this technology includes a patient interface comprising an inflatable chamber capable of being pressurized to a therapeutic pressure at least 4 cmH2O above ambient pressure. The inflatable chamber includes at least one inflatable chamber inlet port, sized and configured to receive an airflow at the therapeutic pressure for patient breathing. The patient interface also includes a sealing structure constructed and arranged to form a seal with an area of ​​the patient's face surrounding an inlet in the patient's airway. The sealing structure has openings therein, allowing the airflow at the therapeutic pressure to be delivered to at least one inlet in the patient's nostrils. The sealing structure is constructed and arranged to maintain the therapeutic pressure in the inflatable chamber throughout the patient's respiratory cycle during use. The patient interface also includes positioning and stabilizing structures to provide force to hold the sealing structure in a therapeutically effective position on the patient's head.

[0061] One form of this technology includes a flow-generating device for generating a breathable gas flow under positive pressure for respiratory therapy, the flow-generating device comprising: A housing having an inlet and an outlet; A blower, comprising a motor and an impeller, for drawing ambient gas into the housing through the inlet and discharging it from the housing through the outlet; and At least one nonwoven fabric is lined or partially lined on one or more internal surfaces of the housing or within the housing.

[0062] One form of this technology includes a flow-generating device for generating a breathable gas flow under positive pressure for respiratory therapy, the flow-generating device comprising: A housing having an inlet and an outlet; A blower, comprising a motor and an impeller, for drawing ambient gas into a housing through an inlet and discharging it from the housing through an outlet; and At least one silencing device comprising a synthetic nonwoven fabric, the silencing device being lined or partially lined on one or more internal surfaces of the housing or within the housing.

[0063] Another form of this technology includes a silencing device suitable for gas flow generating equipment. In some examples, the silencing device comprises a nonwoven fabric, and in other examples, it comprises a synthetic nonwoven fabric.

[0064] Another form of this technology includes a silencing device comprising a nonwoven fabric configured to absorb and / or deflect sound waves within the housing of the device, the device being used to supply a flow of breathable gas under positive pressure for respiratory therapy. In one example, the nonwoven fabric is a synthetic nonwoven fabric.

[0065] In another example, the silencing device is made entirely of synthetic materials or a single synthetic material.

[0066] In another example, a silencing device or nonwoven fabric is wholly or partially lined on one or more outer surfaces of the motor.

[0067] In another example, the housing includes multiple chambers, one or more of which include at least one silencing device.

[0068] In another example, the housing includes a plurality of chambers, at least one of which includes at least one silencing device.

[0069] In another example, the device is configured to define a gas flow path between the inlet and outlet of the housing, and the silencer is at least partially located within the gas flow path.

[0070] In another example, the inner surface of the housing includes one or more flanges, recesses, orifices, channels, notches, or hooks configured to receive at least one silencing device.

[0071] In another example, the nonwoven fabric of the silencing device is configured to include at least two opposing outer surfaces that are spaced apart and connected by at least one sidewall.

[0072] In another example, the nonwoven fabric of the silencing device is configured to bend into a shape around an axis parallel to an outer surface of the synthetic nonwoven fabric.

[0073] In another example, the nonwoven fabric of the silencing device is configured to bend into a shape around an axis perpendicular to the surface of the synthetic nonwoven fabric.

[0074] In another example, the silencing device includes at least one integrally formed flange, recess, orifice, channel, notch, hook, or adhesive configured to allow the silencing device to be attached to the inner surface of the housing of the device.

[0075] In another example, the noise reduction device includes at least one connecting member incorporated into or attached to a nonwoven fabric. In some examples, the connecting member may be half of a male-female connecting member, the opposite half of which is attached to or incorporated into the housing of the device.

[0076] In another example, the silencing device is directly or partially molded into or on the inner wall of the device housing.

[0077] In another example, the silencing device is partially or completely encapsulated by a frame.

[0078] In another example, the frame portion is the overmolded edge.

[0079] In another example, the frame portion includes a porous support.

[0080] In another example, the frame portion includes a front panel of a porous support and an opposing rear panel of the porous support, the front and rear panels of the porous support being connected and spaced apart by at least one sidewall, and a nonwoven fabric positioned between the front and rear panels of the porous support, the periphery of which is surrounded by at least one sidewall of the frame portion.

[0081] In another example, the porous support was configured to define orifices within the support, with the cross-sectional area of ​​the orifices being 4 mm² when the cross-section was measured substantially parallel to the nonwoven fabric. 2 Up to 10000mm 2 .

[0082] In another example, the frame portion includes at least one retaining feature configured to releasably retain the muffler within the housing.

[0083] In other examples, the silencing device is made of a single material. In still other examples, the frame portion and the nonwoven fabric are made of the same material. In some examples, the frame portion and the nonwoven fabric are made of polypropylene.

[0084] In other examples, the nonwoven fabric is a needle-punched nonwoven fabric, a meltblown nonwoven fabric, a spunbond nonwoven fabric, a spunlace nonwoven fabric, and / or a flash-spun nonwoven fabric.

[0085] In other examples, the nonwoven fabric is formed using thermal bonding, hydroentanglement, ultrasonic patterning bonding, needle punching, and / or chemical bonding.

[0086] In another example, the nonwoven fabric of the silencing device includes at least one treated surface to reduce fiber migration from the nonwoven fabric.

[0087] In another example, the nonwoven fabric comprises two opposing treated surfaces.

[0088] In other examples, the surface has undergone heat treatment and / or mechanical treatment.

[0089] In another example, the heat-treated surface is formed by calendering at least one surface of the nonwoven fabric at 120°C to 170°C.

[0090] In another example, the nonwoven fabric includes a sparse layer on at least one surface of the nonwoven fabric. In some forms, the sparse layer is made of nonwoven fabric. In some forms, the sparse layer is made of spunbond nonwoven fabric.

[0091] In another example, the sparse fabric coating is bonded to the nonwoven fabric using thermal bonding, mechanical bonding, and / or adhesives.

[0092] In another example, the nonwoven fabric includes two opposing outer surfaces that have different surface textures, surface roughness, or profiles from each other.

[0093] In another example, the denier number (D) of the nonwoven fabric is 3 to 15.

[0094] In another example, the density of the nonwoven fabric ranges from 50 kg / m³ to 200 kg / m³.

[0095] In another example, the porosity of the nonwoven fabric is between 50% and 90%.

[0096] In another example, the housing includes a plurality of chambers, at least one of which includes at least one silencing device.

[0097] In another example, the housing includes a plurality of chambers, at least one of which includes at least one silencing device positioned within the same chamber as the flow element.

[0098] In another example, the device is configured to define a gas flow path between the inlet and outlet of the housing, and the silencer is at least partially located within the gas flow path.

[0099] In another example, the nonwoven fabric is made of one or more pieces of nonwoven fabric with a thickness between 1 mm and 20 mm.

[0100] In another example, the synthetic nonwoven fabric is polypropylene or polyethylene terephthalate (PET).

[0101] In another example, the nonwoven fabric is made of hollow fibers.

[0102] In another example, the tensile strength of the nonwoven fabric ranges from 20 kN / m to 100 kN / m.

[0103] In another example, the nonwoven fabric has a unit area mass of 200 g / m2 to 1200 g / m2.

[0104] In another example, nonwoven fabrics have a sound absorption coefficient of 0.4 to 0.95 for sounds in the range of 1 kHz to 6 kHz.

[0105] In another example, a nonwoven fabric is positioned within the housing such that as gas moves through the housing, the nonwoven fabric absorbs sound waves as the gas approaches or passes at an angle to the gas.

[0106] In another example, the muffler includes an integrally formed flange, recess, orifice, channel, notch, or hook configured to allow the muffler to be attached to the housing of the device.

[0107] In another example, the silencer is configured to be slidably received by the housing of the device.

[0108] In another example, the device includes a multilayered, interconnected nonwoven fabric.

[0109] In another example, the nonwoven fabric comprises multiple layers of nonwoven fabric of different sizes, which are laminated together to form an irregularly shaped noise-absorbing device.

[0110] In another example, the device includes one or more shaped, molded, or textured outer surface areas to increase the surface area of ​​the noise reduction device.

[0111] In another example, the silencing device is shaped to correspond to the inner surface of the housing.

[0112] In another example, the nonwoven fabric is formed via thermoforming.

[0113] In another example, the nonwoven fabric is inelastic.

[0114] Another aspect of this technology is a patient interface that is molded or otherwise constructed to have a peripheral shape that complements the intended wearer.

[0115] One aspect of this technology is a method for manufacturing equipment.

[0116] Another aspect of this technology is a method for assembling a modular system, which includes selecting a positioning and stabilizing structure and connecting the positioning and stabilizing structure to a first pad or a second pad.

[0117] One aspect of certain forms of this technology is a medical device that is easy to use (e.g., by a person without medical training, by a person with limited dexterity and vision, or by a person with limited experience in using this type of medical device).

[0118] One aspect of this technology is a portable RPT device that can be carried by a person (e.g., in various locations within that person's home).

[0119] One aspect of this technology is a patient interface that can be cleaned at a patient's home, for example, with soapy water, without the need for specialized cleaning equipment. Another aspect of this technology is a humidifier tank that can be cleaned at a patient's home, for example, with soapy water, without the need for specialized cleaning equipment.

[0120] The described methods, systems, apparatuses, and devices can be implemented to improve the functionality of processors, such as processors in dedicated computers, respiratory monitors, and / or respiratory therapy devices. Furthermore, the described methods, systems, apparatuses, and devices can provide improvements in the field of automated management, monitoring, and / or treatment of respiratory conditions, including, for example, sleep-disordered breathing.

[0121] Of course, some of these aspects may form sub-aspects of this technology. Moreover, these sub-aspects and / or individual sub-aspects and / or aspects may be combined in various ways and may also constitute additional aspects or sub-aspects of this technology.

[0122] Other features of the present technology will become apparent from the information contained in the following detailed description, abstract, drawings and claims. Attached Figure Description

[0123] The technology is illustrated in the accompanying drawings by way of example and not limitation, and the same reference numerals in the drawings denote similar elements, including: 3.1 Respiratory Therapy System Figure 1A A system is shown that includes a patient 1000 wearing a patient interface 3000 in the form of a nasal pillow, which receives a positive-pressure air supply from a respiratory therapy (RPT) device 4000. The air from the RPT device 4000 is humidified in a humidifier 5000 and delivered to the patient 1000 along an air circuit 4170. A bed companion 1100 is also shown. The patient is sleeping in a supine position.

[0124] Figure 1B A system is shown that includes a patient 1000 wearing a patient interface 3000 in the form of a nasal mask, which receives a positive-pressure air supply from an RPT device 4000. The air from the RPT device is humidified in a humidifier 5000 and delivered to the patient 1000 along an air circuit 4170.

[0125] Figure 1C A system is shown that includes a patient 1000 wearing a patient interface 3000 in the form of a full-face mask, which receives a positive-pressure air supply from an RPT device 4000. The air from the RPT device is humidified in a humidifier 5000 and delivered to the patient 1000 along an air circuit 4170. The patient is sleeping in a side-lying position.

[0126] Figure 2A A schematic diagram of the human respiratory system is shown, including the nasal cavity and oral cavity, larynx, vocal cords, esophagus, trachea, bronchi, lungs, alveolar sacs, heart, and diaphragm.

[0127] Figure 3A A patient interface in the form of a nasal mask according to the present technology is shown.

[0128] Figure 4A An RPT device of one form according to the present technology is shown.

[0129] Figure 4BThis is a schematic diagram of the pneumatic path of one form of RPT device according to this technology. The upstream and downstream directions are indicated by reference to the blower and patient interface. The blower is positioned upstream of the patient interface and the patient interface is positioned downstream of the blower, regardless of the actual flow direction at any given time. The article located within the pneumatic path between the blower and the patient interface is downstream of the blower and upstream of the patient interface.

[0130] Figure 4C This is a schematic diagram of the electrical components of one form of RPT device according to the present technology.

[0131] Figure 4D A portion of the housing of a pneumatic block of a gas flow generating device including a silencing device, according to the present technology, is shown.

[0132] Figure 4E A silencing device of one form according to the present technology is shown, which is formed for use in a housing or a region of a blower lining a gas flow generating device.

[0133] Figure 4F A portion of the housing of a gas flow generating device according to the present technology is shown, comprising multiple silencing devices lined to the walls of the housing.

[0134] Figure 4F-1 It shows Figure 4F A portion of the housing of the gas flow generating device, indicating the gas flow path within the housing.

[0135] Figure 4G An alternative gas flow generating device according to the present technology is shown, including a silencing device suitable for inclusion within the housing of the gas flow generating device.

[0136] Figure 4H A form of silencing device according to the present technology is shown.

[0137] Figure 4I A cross-section of a noise-reducing device with an overmolded edge portion, according to the present technology, is shown.

[0138] Figure 4J A top view of a noise-reducing device with an overmolded edge portion according to the present technology is shown.

[0139] Figure 4K The surface of a nonwoven fabric prior to surface treatment is shown in one form according to the present technology.

[0140] Figure 4L The surface of a nonwoven fabric after surface treatment is shown in one form according to the present technology.

[0141] Figure 4M This shows a microscopic surface view of a region of a nonwoven fabric after heat treatment of the nonwoven surface.

[0142] Figure 4N A loose cloth layer and a nonwoven fabric layer of sound-absorbing material prior to bonding are shown in one form according to the present technology.

[0143] Figure 5A An isometric view of one form of humidifier according to the present technology is shown.

[0144] Figure 5B An isometric view of one form of humidifier according to the present technology is shown, wherein the humidifier reservoir 5110 is shown removed from the humidifier reservoir base 5130.

[0145] Figure 6A This shows a typical breathing waveform model of a person sleeping.

[0146] Figure 7A A perspective view shows a pad configured to be worn by a patient and to deliver pressurized air to the patient's nose and mouth. Detailed Implementation

[0147] Before describing the technology in further detail, it should be understood that the technology is not limited to the specific examples described herein, which may vary. It should also be understood that the terminology used in this disclosure is for the purpose of describing the specific examples discussed herein and is not intended to be limiting.

[0148] The following description provides various examples of shared characteristics and / or features. It should be understood that one or more features of any one example may be combined with one or more features of another example or other examples. Furthermore, in any of the examples, any single feature or combination of features may constitute another example.

[0149] Terminology Denier number ( d ni The denier (r / ) or denier (abbreviated as D) is used as a unit of measurement for the mass density of fiber yarn, representing the mass in grams of 9,000 meters of fiber.

[0150] 4.1 Therapy

[0151] In another form, the technology includes a method for treating respiratory disorders, which involves applying positive pressure to the inlet of the airway of a patient 1000.

[0152] In some examples of this technique, a positive pressure air supply is provided to the patient's nasal passages through one or both nostrils.

[0153] In some examples of this technology, mouth breathing is restricted, constrained, or prevented.

[0154] 4.2 Respiratory Therapy System

[0155] In one form, the technology includes a respiratory therapy system for treating respiratory disorders. The respiratory therapy system may include an RPT device 4000 for supplying an airflow to a patient 1000 via an air circuit 4170 and a patient interface 3000 or 3800.

[0156] 4.3 Patient Interface

[0157] According to one aspect of this technology, such as Figure 3A The illustrated noninvasive patient interface 3000 includes the following functional aspects: a seal-forming structure 3100, an inflation chamber 3200, a positioning and stabilizing structure 3300, an air vent 3400, a connection port 3600 for connecting to an air circuit 4170, and a forehead support 3700. In some forms, the functional aspects may be provided by one or more physical components. In some forms, a single physical component may provide one or more functional aspects. In use, the seal-forming structure 3100 is arranged to surround the inlet of the patient's airway to maintain positive pressure at the inlet of the patient's airway. The sealed patient interface 3000 is therefore suitable for the delivery of positive pressure therapy.

[0158] 4.4 RPT device

[0159] An RPT device 4000 according to one aspect of the present technology includes mechanical, pneumatic and / or electrical components and is configured to perform one or more algorithms 4300, such as any of the methods described herein in whole or in part. The RPT device 4000 may be configured to generate an airflow for delivery to a patient's airway, such as for treating one or more respiratory conditions described elsewhere in this document.

[0160] In one embodiment, the RPT device 4000 is constructed and arranged to deliver an airflow in the range of -20 L / min to +150 L / min while maintaining a positive pressure of at least 4 cmH2O, at least 10 cmH2O, or at least 20 cmH2O.

[0161] The RPT device may have an outer housing 4010, which is formed in two parts: an upper portion 4012 and a lower portion 4014. Furthermore, the outer housing 4010 may include one or more panels 4015. The RPT device 4000 includes a base 4016 that supports one or more internal components of the RPT device 4000. The RPT device 4000 may include a handle 4018.

[0162] The pneumatic path of the RPT device 4000 may include one or more air path articles, such as an inlet air filter 4112, an inlet silencer 4122, a pressure generator 4140 (e.g., a blower 4142) capable of supplying air at positive pressure, an outlet silencer 4124, and one or more transducers 4270, such as a pressure sensor 4272 and a flow sensor 4274.

[0163] One or more air path items may be located within a removable integral structure, referred to as pneumatic block 4020. Pneumatic block 4020 may be located within an outer housing 4010. In one form, pneumatic block 4020 is supported by or formed as part of a base frame 4016.

[0164] like Figure 4C As shown, the RPT device 4000 may include a power supply 4210, one or more input devices 4220, a central controller 4230, a therapy device controller 4240, a pressure generator 4140, one or more protection circuits 4250, a memory 4260, a transducer 4270, a data communication interface 4280, and one or more output devices 4290. Electrical components 4200 may be mounted on a single printed circuit board assembly (PCBA) 4202. In an alternative embodiment, the RPT device 4000 may include more than one PCBA 4202.

[0165] 4.4.1 Mechanical and Pneumatic Components of RPT Unit

[0166] The RPT device may include one or more of the following components in an overall unit. In an alternative form, one or more of the following components may be positioned as respective separate units.

[0167] 4.4.1.1 Air Filter

[0168] One form of RPT device according to the present technology may include one air filter 4110, or multiple air filters 4110.

[0169] exist Figure 4B In one embodiment shown, the inlet air filter 4112 is located at the beginning of the pneumatic path upstream of the pressure generator 4140.

[0170] exist Figure 4B In one embodiment shown, an outlet air filter 4114, such as an antibacterial filter, is positioned between the outlet of the pneumatic block 4020 and the patient interface 3000 or 3800.

[0171] 4.4.1.2 Muffler

[0172] One form of RPT device according to the present technology may include one or more mufflers 4120.

[0173] In one form of this technology (for example, see...) Figure 4B The inlet silencer 4122 is located in the pneumatic path upstream of the pressure generator 4140.

[0174] In one embodiment of this technology, the outlet silencer 4124 is located in the pneumatic path between the pressure generator 4140 and the patient interface 3000 or 3800.

[0175] 4.4.1.3 Pressure Generator

[0176] In one form of this technology, the pressure generator 4140 for generating a positive pressure airflow or air supply is a controllable blower 4142. For example, the blower 4142 may include a brushless DC motor 4144 having one or more impellers. The impellers may be located in a volute. The blower is capable of delivering an air supply at a positive pressure ranging from about 4 cmH2O to about 20 cmH2O, or in other forms up to about 30 cmH2O, for example at a rate up to about 120 liters per minute, when delivering respiratory pressure therapy. The blower may be as described in any of the following patents or patent applications, the entire contents of which are incorporated herein by reference: U.S. Patent No. 7,866,944; U.S. Patent No. 8,638,014; U.S. Patent No. 8,636,479; and PCT Patent Application Publication No. WO 2013 / 020167.

[0177] The pressure generator 4140 can be controlled by the therapy device controller 4240.

[0178] In other forms, the pressure generator 4140 may be a piston-driven pump, a pressure regulator connected to a high-pressure source (e.g., a compressed air reservoir), or a bellows.

[0179] 4.4.1.4 Transducer

[0180] The transducer can be located inside or outside the RPT device. An external transducer can be located on, for example, an air circuit (e.g., a patient interface) or form part of an air circuit. The external transducer can be in the form of a non-contact sensor, such as a Doppler radar motion sensor that transmits data or transfers it to the RPT device.

[0181] In one form of this technology (for example, see...) Figure 4BOne or more transducers 4270 are located upstream and / or downstream of pressure generator 4140. One or more transducers 4270 may be configured and arranged to generate signals representing characteristics of airflow, such as flow rate, pressure, or temperature at that point in the aerodynamic path.

[0182] In one form of this technology, one or more transducers 4270 may be located near the patient interface 3000 or 3800.

[0183] In one embodiment, the signal from transducer 4270 can be filtered, for example, by low-pass filtering, high-pass filtering, or band-pass filtering.

[0184] 4.4.1.4.1 Flow sensor

[0185] The flow sensor 4274 according to this technology can be based on a differential pressure transducer, such as the SDP600 series differential pressure transducer from SENSIRION.

[0186] In one configuration, the signal generated by the flow sensor 4274 and representing the flow rate is received by the central controller 4230.

[0187] 4.4.1.4.2 pressure sensor

[0188] The pressure sensor 4272 according to this technology is positioned in fluid communication with the pneumatic path. An example of a suitable pressure sensor is a transducer from the HONEYWELL ASDX series. Alternatively, a suitable pressure sensor is a transducer from the GENERALELECTRIC NPA series.

[0189] In one configuration, the signal generated by pressure sensor 4272 and representing pressure is received by central controller 4230.

[0190] 4.4.1.4.3 Motor speed transducer

[0191] In one embodiment of this technology, a motor speed transducer 4276 is used to determine the rotational speed of a motor 4144 and / or a blower 4142. The motor speed signal from the motor speed transducer 4276 can be provided to a therapy device controller 4240. The motor speed transducer 4276 can be, for example, a speed sensor, such as a Hall effect sensor.

[0192] 4.4.1.5 Anti-overflow valve

[0193] like Figure 4BAs shown, in one form of this technology, an anti-backflow valve 4160 is positioned between the humidifier 5000 and the pneumatic block 4020. The anti-backflow valve is constructed and arranged to reduce the risk of water flowing upstream from the humidifier 5000 to, for example, the motor 4144.

[0194] 4.4.2 Flow Limiter

[0195] In many devices, flow limiters are included in the airflow path. Limiters help reduce noise and provide differential pressure for flow and pressure measurements.

[0196] 4.4.3 Silencing device

[0197] In one form, this technology involves using nonwoven fabrics to manufacture a silencing device for reducing noise generated in gas flow generating equipment. Many devices are known to utilize gas flow / airflow generation as a key operating component, such as vacuum cleaners, blowers, heating and cooling fans, air guns, and compressed air dust collectors. Typically, a large volume of gas / air is generated within a housing using a blower with a rotating impeller to create a vacuum. The vacuum forces ambient air into the blower through an inlet, where it is diverted by the rotating impeller blades. As the pressure within the housing increases, the volume of the gas flow increases, and it is then discharged through the housing outlet. Noise is generated as the air / gas moves through the blower and housing, passing over objects, edges, gaps, or cavities.

[0198] In respiratory therapy devices, sound suppression can be achieved by dividing the air path into a series of chambers connected via inertial tubes, ultimately forming an expansion silencer arrangement. The use of silencers significantly improves the performance of such arrangements by: (a) absorbing sound; and (b) suppressing the effects of air cavity resonance.

[0199] As devices are manufactured to smaller sizes, the size of the gas flow path decreases and may become more tortuous, resulting in increased noise as the gas passes through the housing.

[0200] Compared to traditional foam, the use of nonwoven fabrics for noise reduction in RPT devices introduces numerous advantages, especially in smaller devices. In smaller devices, the reduced space within the flow generation equipment both increases noise generated during operation and reduces the space available for noise reduction. Compared to foam, the nonwoven fabrics of this technology can be manufactured with greater precision and consistency, where characteristics such as porosity, density, size, surface texture, and profile can be controlled and consistently replicated during the manufacturing process. This reduces waste, provides consistent noise reduction effectiveness during large-scale manufacturing, and ensures continuous airflow.

[0201] Any surface treatment using a single material to form synthetic nonwoven fabrics, frames or connecting parts and / or sound-absorbing devices allows for the manufacture of fully recyclable devices, thereby reducing waste at the end of the product's life and improving product sustainability.

[0202] In this technology, a nonwoven fabric is lined or partially lined on one or more areas of the internal surface of the housing of the flow generating device, or on the surface of another component that is itself held within the housing and / or surrounded by the housing. This introduces at least one surface to absorb sound waves as gas passes near or through the nonwoven fabric at an angle. This contrasts with the case where a hard, smooth housing surface reflects sound waves, which can lead to increased noise. The nonwoven fabric has a porous or semi-porous, mesh-like structure that reduces the amplitude of sound waves as they move through and are absorbed by the nonwoven structure.

[0203] One surface of the nonwoven fabric is in close proximity to the inner surface it adheres to, resulting in a reduction or absence of airflow / gas flow that completely passes through the nonwoven fabric. In this respect, the nonwoven fabric acts as a sound absorber rather than a filter. Airflow / gas flow and sound waves traveling through the nonwoven fabric that penetrate the nonwoven fabric and come into contact with the inner shell wall are reflected back to the nonwoven fabric, thereby further enhancing the sound absorption capacity of the nonwoven fabric.

[0204] Figures 4D to 4N The diagram shows a silencer 4130, which can be used as a standalone component or, in one example of the art, integrated into one or more styles of pneumatic blocks 4020 of a gas generating device. The pneumatic block 4020 includes a housing in the form of a hollow frame 4016, within which a pressure generator 4140 for generating a gas flow or gas supply under positive pressure is housed. The pressure generator 4140 is a controllable blower 4142. The frame 4016 includes an inlet 4017 and an outlet 4019. Figure 4F-1 The arrows in the diagram illustrate an example gas flow path where gas flows into housing 4016 through inlet 4017, passes through flow restrictor 4111, bypasses the central chamber 4016C of housing 4016, and then passes through a second flow restrictor 4112 into adjacent chamber 4016D. The gas flow path exits chamber 4016D via orifice 4116 to return to the central chamber 4016C, passes through the central chamber 4016C, exits via orifice 4117 into chamber 4016E, and then exits housing 4016 through outlet 4019. The flow restrictors are configured and / or shaped to help reduce noise and provide differential pressure for flow and pressure measurements within the housing.

[0205] Nonwoven fabric 4130 is shown in multiple locations within the base frame 4016, lining the inner surfaces of chambers 4016C, 4016D, and 4016E of the base frame 4016 in multiple locations.

[0206] like Figures 4D to 4F-1 As shown, the housing includes a cylindrical base frame 4016, wherein the base frame cover 4016A ( Figure 4D It can be used with the 4016B base frame ( Figure 4F The components are connected to form a base frame 4016. The base frame housing 4016 includes inner walls defining chambers 4016C, 4016D, and 4016E. A plurality of silencing devices 4130 are mounted inside the base frame 4016, lining the inner surface 4040. In some areas, the silencing devices 4130 include a nonwoven fabric 4131 whose dimensions are set to directly correspond to the boundaries of the inner base frame walls defined by the internal components of the pneumatic block. Figure 4E Three separate silencing devices 4130A made of nonwoven fabric 4131 are shown, wherein the shape of the silencing devices 4130A is thermoformed such that the silencing devices 4130A retain a curved form to mimic the shape of the inner shell wall, and the silencing devices are designed to be received against the inner shell wall. In the example shown, the chamber 4016E is lined with the curved silencing devices 4130A in the form of nonwoven fabric. In some examples, the nonwoven fabric 4131 forming the silencing devices 4130A is configured to include at least two opposing outer surfaces 4136 and 4137, which are spaced apart and connected by at least one sidewall 4138. Figure 4E In the example, the nonwoven fabric 4161 is configured to be bent into a shape about an X-axis parallel to the outer surface 4136, such that surface 4136 is concave and the opposite surface 4137 is convex. The silencing device 4130A may include any number or shape of curves as needed to allow it to fit or connect tightly to the inner wall of the base frame 4161.

[0207] In other examples, the silencing device 4130A may be flexible and able to adapt to any curved surface against which it is mounted.

[0208] The muffler 4130A may be formed to include a connection area 4133, which may be in the form of a flange, notch, groove, protrusion or slit. When the connection area 4133 engages with a corresponding feature in the inner wall of the base frame 4016, the muffler 4130A is allowed to be held in a certain position within the housing.

[0209] like Figure 4D and Figure 4F and Figure 4GAs shown, the silencer 4013A is releasably received within the base frame 4016 and flush against the inner surface 4040 to line the inner wall of the housing. The silencer 4130 can be mounted perpendicular to the gas flow in the housing, parallel to the gas flow in the housing, or at any angle in between, thereby providing material for attenuating, passing through, or reflecting sound depending on the mounting location. Because the silencers of this technology can be consistently manufactured to specific dimensions and compositions, thereby ensuring consistent airflow, the silencer 4103 can be positioned within the same chamber as the flow limiter 4111 or 4112, adjacent to, near, or directly against the flow limiter.

[0210] Figure 4F-1 Arrows are shown illustrating an example gas flow path through a pneumatic block. In one example, the housing and internal components cooperate to form an airflow path having at least one generally U-shaped path from housing inlet 4017 to housing outlet 4019. For example, the U-shaped airflow path may include an inlet branch extending from housing inlet 4017, an outlet branch extending from housing outlet 4019, and a connecting branch connecting the inlet and outlet branches. In one example, the inlet and outlet branches are substantially parallel to each other. In one example, one or more flow restrictors and silencers are provided along the inlet branch. In one example, one or more silencers and flow restrictors are provided along the connecting branch. In one example, one or more silencers and flow restrictors are provided along the outlet branch.

[0211] Depending on the shape of the pneumatic block, one or more different silencing devices may be required to effectively line or cover the inner surface 4040, wherein the silencing devices are shaped to avoid or closely fit the internal components (e.g., including but not limited to baffles, flanges, inner walls or connecting devices).

[0212] like Figure 4G As shown, a noise reduction device 4130D is formed from a nonwoven fabric 4161 as a substantially planar sheet with a thickness of 5 mm to 10 mm, the nonwoven fabric 4161 being shaped around its periphery to line the inner surface 4040 of the base frame 4016. Figure 4G In one example, this forming includes a curved wall 4162, which is shaped to provide spacing for and surround the blower 4142. Multiple individual silencers 4130D can be stacked on top of each other, placed individually, or connected or laminated together using mechanical / thermal methods. Figure 4GAnother example is provided of a smaller silencing device 4130E, which is shaped to surround and be held by an internal feature of the base frame 4016. Any number of individual silencing devices may be included within the housing of the gas flow generating device to absorb sound, and the size and shape of these devices may be adjusted as needed to allow them to be lined on the internal surface 4040.

[0213] Figure 4F Further examples of silencing devices, 4130B and 4130C, are shown, which include a nonwoven fabric 4131 held at a fixed size by a frame portion 4700. In the examples, the frame 4131 or 4700 may be overmolded together with the nonwoven fabric 4131 or formed as an accessible cage structure, thereby allowing removal or replacement of the internally housed nonwoven fabric.

[0214] In other examples not shown, the muffler 4130 may be directly molded into the inner wall of the housing. Molding may be configured such that the inner housing wall forms at least a portion of the frame 4131, which provides support for the muffler 4130. In some examples, any example of the frame portion described herein may be formed together with or partially formed into the inner housing wall.

[0215] The frame portion 4700 supports the nonwoven fabric 4161 at a fixed size, ensuring that any silencers 4130B / 4130C, which remain within the base frame 4016 or within any gas flow path of the gas generating device, do not move during use, thereby providing consistent sound absorption quality and consistent dimensions that can be easily replicated during mass production.

[0216] exist Figure 4F In some of the examples shown, the frame portion 4700 is configured as a support structure surrounding a substantially planar portion of the nonwoven fabric 4161, the support having a front panel 4701 (and optionally an opposing rear panel (not shown)), the front panel being configured to cover at least one planar surface of the nonwoven fabric and defining at least one aperture 4800 thereby exposing the nonwoven fabric 4161 to an internal housing space defined by the hollow base frame 4161, and subsequently providing the nonwoven fabric 4161 for sound absorption. The frame portion 4700 may also include a frame edge 4702 that is connected to and supports the periphery of or a portion thereof of the nonwoven fabric 4161.

[0217] In some examples, the frame portion includes an edge 4203 surrounding a front panel and / or a rear panel 4702, which is configured to define a plurality of openings 4800. In one example, these openings may have hexagonal perimeters, thus forming a honeycomb support structure. The frame portion 4700 may be configured to define a series of openings 4800 of various sizes and shapes, such as circular, triangular, octagonal, elliptical, rectangular, square, or irregular polygons, with larger openings exposing more nonwoven fabric sizes or shapes. In one example of the silencing device 4130C, a honeycomb support structure is formed in the front panel 4702 and the opposite rear panel (not shown) of the frame portion 4700. The honeycomb structure includes a plurality of hexagonal or partially hexagonal walls defining openings 4135 and circular walls defining larger openings 4136. The frame portion 4700 can be configured such that the front panel 4702 and / or the opposite rear panel have a porosity of 40% to 95%, wherein the porosity is determined by the mounting location and exposure to the gas flow path.

[0218] In the provided example, the orifice 4136 is sized to expose a larger surface area of ​​the nonwoven fabric 4161 to the passing gas flow, while still providing strength and dimensional control for the silencer. The frame portion 4700 allows a region of the nonwoven fabric 4161 to be firmly supported in the gas path through the base frame 4016, thereby ensuring rigidity and dimensional control under pressure from the moving gas flow.

[0219] The frame portion 4700 can be configured to cover the edge portions or surface areas of the nonwoven fabric; see further examples. Figure 4H , Figure 4I and Figure 4J . Figure 4I A cross-sectional view of a nonwoven fabric 4161 is shown, having a frame portion 4700 formed as an overmolded edge to provide rigidity to the nonwoven fabric 4161 by surrounding or partially surrounding its periphery. When formed as an edge 4720, the frame portion 4700 may have a substantially U-shaped cross-section, with the bottom 4719 of the "U" abutting the edge region of the nonwoven fabric 4161, and opposing sidewalls 4715 of the "U" shape 4716 molded around the side edges of the front surface 4163 and rear surface 4164 of the nonwoven fabric 4161. In some forms, the sidewalls 4715 may be configured or sized between 2 mm and 10 mm to frame the front and rear surfaces of the nonwoven fabric 4161, wherein the dimensions of the sidewalls 4715 may optionally differ on each surface, may optionally vary in different regions surrounding the periphery of the nonwoven fabric, and are sized to enable and facilitate the integration of the nonwoven fabric into a frame 4016.

[0220] In some forms, the retaining feature 4717 may be incorporated into the frame portion in the form of a channel, a protrusion, an edge, a flange, or half of a connecting member. This retaining feature is designed to allow the muffler to be securely connected to the interior of the hollow chamber, thereby reducing any clicking or movement that may increase rather than decrease the sound within the device. The retaining feature 4717 may be formed on any surface of the frame portion 4700, and in one example, is a small protrusion extending from the bottom 4717 of the edge 4720 and extending around or partially around the length of the edge 4720. The retaining feature 4717 allows the muffler 4130 to be slidably held in a corresponding recess formed in the inner surface 4040 of the base 4016.

[0221] Figure 4J A top view of a noise reduction device 4130D is shown, which has an overmolded edge 4720 surrounding the periphery of a nonwoven fabric 4161.

[0222] The nonwoven fabric 4161 is shaped to have a periphery corresponding to an area of ​​the inner frame surface and to have a specific thickness that allows it to fit snugly against the frame 4016 without obstructing airflow. The periphery of the nonwoven fabric 4161 may be shaped to include connecting portions that receive or attach to / abut against ribs, flanges, or protrusions formed on the inner surface of the frame 4016.

[0223] In some examples, the silencing device 4130 is constructed of a substantially rectangular sheet of fabric, bent about a transverse axis perpendicular to the longitudinal axis of the rectangular nonwoven fabric, and may include grooves 4131 or recesses 4132 to facilitate connection. These connection portions may be formed, for example, using thermoforming or precision cutting. The curvature of the nonwoven fabric may be fixed using techniques such as thermoforming prior to assembly, or a substantially flat piece of nonwoven fabric may be used that conforms to the curved surface upon insertion. The nonwoven fabric may be of any shape as needed to effectively line at least a portion of the inner surface of the blower housing.

[0224] When the silencer 4130 is used in a gas flow generating device, reducing the migration of fibers from the nonwoven fabric 4161 helps prevent small microfibers from being released into the gas flow as air passes through or through the nonwoven fabric. If such fibers are inhaled into a patient's lungs or airway, they could potentially harm the patient's health.

[0225] Many nonwoven fabrics in their raw state have a fluffy or fuzzy outer surface, with some fibers not fully adhered to the nonwoven web extending from the outer surface of the product. By treating the surface of the nonwoven fabric, the fibers can be more effectively retained within the nonwoven fabric and will not be released when the silencing device is subjected to friction (whether due to passing airflow or during the installation and removal of the silencing device).

[0226] Figure 4K A close-up view of the nonwoven fabric 4161 with a fluffy surface (from which fibers 4162 extend) is shown prior to further surface treatment. Figure 4L It shows the smoother surface obtained after surface treatment.

[0227] Various surface treatments can be applied to nonwoven fabrics to create smooth surfaces that reduce or prevent fiber migration. Combining nonwoven fabrics with frame components, as described in more detail above, can also help reduce fiber migration.

[0228] The nonwoven fabrics used in this invention can be made from recyclable synthetic materials such as polypropylene, polyethylene terephthalate (PET), nylon, polyester, or viscose fibers. Especially for medical applications, synthetic nonwovens are preferred to meet regulatory requirements regarding material hygiene, safety, and quality. In alternative examples, a combination of natural and synthetic fibers can be used, or a combination of fibers of different lengths, strengths, structures (hollow or solid, different cross-sectional shapes, such as circular, trefoil, grooved, crimped), or origins can be used to create nonwovens with optimized sound absorption capabilities.

[0229] The nonwoven fabric used in this invention may be needle-punched short fiber nonwoven fabric, meltblown nonwoven fabric, spunbond nonwoven fabric manufactured by thermal bonding process, spunlace nonwoven fabric manufactured by hydroentanglement, or flash-steamed nonwoven fabric.

[0230] Surface finishing techniques for nonwoven fabrics may include mechanical / thermomechanical finishing, such as opening and winding, calendering, calendering and recalendering, compression finishing, singeing, nano finishing, drying, shearing, flocking, perforation, polishing, softening and heat setting, or chemical finishing (including the use of coating agents).

[0231] Different manufacturing methods are suitable for different fiber types and lengths, and produce nonwoven fabrics with different sound absorption properties.

[0232] Enhanced sound absorption is a preferred characteristic of the nonwovens used in this invention; however, when selecting the best nonwoven for a particular application, different characteristics may also be considered, such as the nonwoven's ability to maintain its shape, its adaptability to precise cutting, and different surface textures.

[0233] Referring to the accompanying drawings, when the silencing device 4130 is used in a gas flow generating device, reducing the migration of fibers from the nonwoven fabric 4161 helps prevent small microfibers from being released into the gas flow as air passes through or through the nonwoven fabric. If such fibers are inhaled into a patient's lungs or airway, they could potentially harm the patient's health.

[0234] Many nonwoven fabrics in their raw state have a fluffy or fuzzy outer surface, with some fibers not fully adhered to the nonwoven web extending from the outer surface of the product. By treating the surface of the nonwoven fabric, the fibers can be more effectively retained within the nonwoven fabric and will not be released when the silencing device is subjected to friction (whether due to passing airflow or during the installation and removal of the silencing device).

[0235] In one example, nonwoven fabric 4161 is a polypropylene nonwoven, and the surface of the nonwoven is calendered at 120°C to 170°C to improve the adhesion of the nonwoven fibers. Surface calendering of nonwoven fabrics can create a smooth, polished surface on the fabric and also impart stiffness to the product, which is achieved by passing the nonwoven through smooth, heated rollers. Figure 4M A noise-reducing device 4130 with a calendered surface is shown, and its microscopic view shows the smooth area 4400 imparted to the nonwoven fibers after calendering. In addition to smoothing the outer surface of the nonwoven fibers, applying the calendering process at a temperature corresponding to the melting point of the nonwoven fibers also causes the fibers on the nonwoven surface to fuse together, so that a cohesive fiber web is formed after cooling.

[0236] In some examples, the nonwoven fabric is made of polypropylene, polyester, or a combination thereof. Surface calendering at a temperature corresponding to the melting point of these compounds produces an effective surface structure that reduces fiber migration in the noise-reducing device.

[0237]

[0238] Figure 4K A close-up view of a nonwoven fabric with a fluffy surface is shown before further surface treatment. Figure 4L It shows the smoother surface obtained after surface treatment.

[0239] In another example, surface treatment to reduce fiber migration in nonwovens can be achieved by adding a sparse fabric layer to one or more nonwoven surfaces. The sparse fabric layer is an additional layer fused to the nonwoven fabric to increase stability, strength, and / or improve surface smoothness and reduce fiber migration.

[0240] The spunbond nonwoven fabric layer can be in synthetic form, such as polyester, polypropylene, or polyethylene, and is applied or laminated to the nonwoven surface using thermomechanical bonding without the addition of adhesives or resin binders. Noise-absorbing devices of this technology can use spunbond nonwoven spunbond fabric layers, and examples of this are shown in... Figure 4N The image shows an unbonded sparse fabric layer 4500 formed to adhere to the surface of a nonwoven fabric 4161. The sparse fabric layer may be laminated to one or both surfaces of the nonwoven fabric.

[0241] As described in more detail above, combining nonwoven fabrics with the frame portion can also help reduce fiber migration.

[0242] In some aspects of this technology, a nonwoven fabric is made into a component that is shaped to be received against the inner surface of a housing in a gas flow generating device. The shape can be a flat sheet with regular or irregular edge shapes to accommodate flanges, ridges, channels, or inner walls within the housing.

[0243] In some examples, the nonwoven fabric is inelastic to encourage it to maintain the desired shape.

[0244] The nonwoven fabric can be made from a single layer with a thickness of 1 mm, 2 mm, 3 mm, 4 mm, 5 mm, 6 mm, 7 mm, 8 mm, 9 mm, 10 mm, 11 mm, 12 mm, 13 mm, 14 mm, 15 mm, 16 mm, 17 mm, 18 mm, 19 mm, or 20 mm to 25 mm, and in some examples, the thickness is 2 mm to 8 mm. Alternatively, multiple layers of nonwoven fabric can be mounted on the housing with overlapping or partially overlapping structures, or can be bonded / laminated together by mechanical or chemical means to form a multilayer component.

[0245] Nonwoven fabrics can be shaped into regular or irregular three-dimensional polygons or curved shapes. One method for manufacturing shaped nonwoven fabrics involves using thermoforming or pressure forming, ultrasonic cutting and welding, radio frequency cutting and welding, hot die-cutting or cold die-cutting, or laser cutting. Such techniques allow nonwoven fabrics to have, for example, curved shapes to closely match the shape of housing components; shaped surfaces that increase the surface area of ​​the nonwoven fabric, thereby improving sound absorption; or recesses, hooks, or flanges to facilitate connections between two or more nonwoven fabric components or between the nonwoven fabric and the surface of a device.

[0246] The surface roughness, texture, or profile of a nonwoven fabric may vary in different areas. For example, one side of the fabric may be relatively smooth to rest against or line the shell wall, while the opposite second side may have a rougher or textured surface to improve sound absorption.

[0247] In some examples of this invention, a range of different nonwoven fabric samples were used in the gas flow generation device. The table below details the different properties of three sample fabrics: Table 1

[0248] The above characteristics are just a small sample of nonwoven fabrics applicable to this technology.

[0249] The properties of nonwoven fabrics that may be suitable for this technology include one or more of the following: - Tensile strength ranges from 20 kN / m to 100 kN / m; - The mass per unit area is 200g / m2 to 1200g / m2; - The absorption coefficient for sounds in the range of 1kHz to 6kHz is 0.4 to 0.95; - The porosity of nonwoven fabrics is between 50% and 90%; - The density of nonwoven fabrics ranges from 50 kg / m³ to 200 kg / m³; - The denier number (D) of the fiber is in the range of 1D to 20D.

[0250] The denier number of the fibers used in nonwoven fabrics can be 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 1, 18, 19, 20, or fractional denier fibers. In some examples, nonwoven fabrics are made using 6-denier and 15-denier fibers, where limited differences in acoustic performance between different denier fibers are identified based on preliminary objective and subjective testing.

[0251] The combination of fiber denier number and nonwoven fabric density allows for the creation of nonwovens with specific porosity characteristics. Preliminary tests indicate that high-density materials offer better sound performance, but sound attenuation is not significantly improved above approximately 170 kg / m³. The desired density can be achieved by layering and bonding the nonwoven fabric during the manufacturing process.

[0252] 4.4.4 Electrical components of RPT device

[0253] 4.4.4.1 Power Supply

[0254] The power supply 4210 may be located inside or outside the outer housing 4010 of the RPT device 4000.

[0255] In one embodiment of this technology, power supply 4210 supplies power only to RPT device 4000. In another embodiment of this technology, power supply 4210 supplies power to both RPT device 4000 and humidifier 5000.

[0256] 4.4.4.2 Input Device

[0257] In one form of this technology, the RPT device 4000 includes one or more input devices 4220 in the form of buttons, switches, or dials to allow human interaction with the device. The buttons, switches, or dials can be physical devices or software devices accessible via a touchscreen. In one form, the buttons, switches, or dials can be physically connected to an external housing 4010, or in another form, they can communicate wirelessly with a receiver electrically connected to a central controller 4230.

[0258] In one form, the input device 4220 may be constructed and arranged to allow a person to select values ​​and / or menu options.

[0259] 4.4.4.3 Central Controller

[0260] In one embodiment of this technology, the central controller 4230 is one or more processors adapted to control the RPT device 4000. The central controller 4230 in... Figure 4C and Figure 4C As shown in -1.

[0261] Suitable processors may include x86 Intel processors, processors based on ARM® Cortex®-M processors from ARM Holdings, and microcontrollers such as the STM32 series from STMicroelectronics. In some alternative forms of this technology, 32-bit RISC CPUs, such as the STR9 series microcontrollers from STMicroelectronics, or 16-bit RISC CPUs, such as processors from the MSP430 family of microcontrollers manufactured by Texas Instruments, may also be applicable.

[0262] In one form of this technology, the central controller 4230 is a dedicated electronic circuit.

[0263] In one form, the central controller 4230 is an application-specific integrated circuit (ASIC). In another form, the central controller 4230 includes discrete electronic components.

[0264] The central controller 4230 can be configured to receive input signals from one or more transducers 4270, one or more input devices 4220, and / or the humidifier 5000.

[0265] The central controller 4230 can be configured to provide output signals to one or more of the output device 4290, pressure generator 4140, therapy device controller 4240, data communication interface 4280, and humidifier 5000.

[0266] In some forms of this technology, the central controller 4230 is configured to implement one or more methods described herein, such as one or more algorithms 4300 that can be implemented using processor control instructions, which are represented as a computer program stored in a non-transient computer-readable storage medium such as memory 4260. In some forms of this technology, the central controller 4230 may be integrated with the RPT device 4000. However, in some forms of this technology, some methods may be performed by a remotely located device. For example, a remotely located device may determine the control settings of a ventilator or detect respiratory-related events by analyzing stored data (such as from any of the sensors described herein).

[0267] 4.4.4.4 Protection Circuit

[0268] One or more protection circuits 4250 according to the present technology may include electrical protection circuits, temperature and / or pressure safety circuits.

[0269] 4.4.4.5 Memory

[0270] According to one embodiment of the present technology, the RPT device 4000 includes a memory 4260, such as non-volatile memory. In some embodiments, the memory 4260 may include battery-powered static RAM. In some embodiments, the memory 4260 may include volatile RAM.

[0271] The memory 4260 may be located on PCBA 4202. The memory 4260 may be in the form of EEPROM or NAND flash memory.

[0272] Additionally or alternatively, the RPT device 4000 includes a removable memory 4260, such as a memory card manufactured according to the Secure Digital (SD) standard.

[0273] In one form of this technology, memory 4260 acts as a non-transitory computer-readable storage medium storing computer program instructions that represent one or more methods described herein, such as one or more algorithms 4300.

[0274] 4.4.4.6 Data Communication System

[0275] In one form of this technology, a data communication interface 4280 is provided, which is connected to a central controller 4230 (see, for example, [link to relevant documentation]). Figure 4CThe data communication interface 4280 can be connected to a remote external communication network 4282 and / or a local external communication network 4284. The remote external communication network 4282 can be connected to a remote external device 4286. The local external communication network 4284 can be connected to a local external device 4288.

[0276] In one embodiment, the data communication interface 4280 is part of the central controller 4230. In another embodiment, the data communication interface 4280 is separate from the central controller 4230 and may include an integrated circuit or a processor.

[0277] In one embodiment, the remote external communication network 4282 is the Internet. The data communication interface 4280 can connect to the Internet using wired communication (e.g., via Ethernet or fiber optic) or wireless protocols (e.g., CDMA, GSM, LTE).

[0278] In one form, the local external communication network 4284 utilizes one or more communication standards, such as Bluetooth or consumer infrared protocols.

[0279] In one form, the remote external device 4286 is one or more computers, such as a cluster of networked computers. In another form, the remote external device 4286 may be a virtual computer rather than a physical computer. In either case, such a remote external device 4286 may be accessible to a properly authorized person, such as a clinician.

[0280] The local external device 4288 can be a personal computer, mobile phone, tablet computer, or remote control device.

[0281] 4.4.4.7 Includes optional display and alarm output devices.

[0282] The output device 4290 according to this technology can take the form of one or more of a visual, audio, and tactile unit. The visual display can be a liquid crystal display (LCD) or a light-emitting diode (LED) display.

[0283] 4.4.4.7.1 Display driver

[0284] The display driver 4292 receives characters, symbols, or images as input for display on the display 4294 and converts them into commands that cause the display 4294 to display those characters, symbols, or images.

[0285] 4.4.4.7.2 monitor

[0286] Display 4294 is configured to visually display characters, symbols, or images in response to commands received from display driver 4292. For example, display 4294 may be an eight-segment display, in which case display driver 4292 converts each character or symbol (such as the number "0") into eight logic signals that indicate whether the eight corresponding segments will be activated to display a specific character or symbol.

[0287] 4.5 Air Circuit

[0288] According to one aspect of the technology, the air circuit 4170 is a conduit or tube that is constructed and arranged to allow airflow to travel between two components (such as the RPT device 4000 and the patient interface 3000 or 3800) during use.

[0289] Specifically, the air circuit 4170 can be fluidly connected to the outlet and patient interface of the pneumatic block 4020. The air circuit may be referred to as an air delivery tube. In some cases, separate branches of the circuit may exist for inhalation and exhalation. In other cases, a single branch is used.

[0290] In some forms, the air circuit 4170 may include one or more heating elements configured to heat air in the air circuit, for example, to maintain or raise the temperature of the air. The heating element may be in the form of a heating wire circuit and may include one or more transducers, such as temperature sensors. In one form, the heating wire circuit may be helically wound around an axis of the air circuit 4170. The heating element may be connected to a controller, such as a central controller 4230. An example of an air circuit 4170 including a heating wire circuit is described in U.S. Patent 8,733,349, which is incorporated herein by reference in its entirety.

[0291] 4.5.1 Humidifier

[0292] 4.5.2 Humidifier Overview

[0293] In one form of this technology, a humidifier 5000 is provided (e.g., such as...). Figure 5A As shown), it is used to change the absolute humidity of the air or gas intended to be delivered to the patient relative to ambient air. Typically, a humidifier 5000 is used to increase the absolute humidity and temperature of the airflow (relative to ambient air) before it is delivered to the patient's airway.

[0294] Humidifier 5000 may include a humidifier reservoir 5110, a humidifier inlet 5002 for receiving airflow, and a humidifier for delivering humidified air. Air The humidifier outlet is 5004. In some forms, such as... Figure 5A and Figure 5BAs shown, the inlet and outlet of the humidifier reservoir 5110 can be a humidifier inlet 5002 and a humidifier outlet 5004, respectively. The humidifier 5000 may also include a humidifier base 5006, which is adapted to receive the humidifier reservoir 5110 and includes a heating element 5240.

[0295] 4.5.2.1 Respiratory waveform

[0296] Figure 6A This diagram illustrates a typical breathing waveform model of a person sleeping. The horizontal axis represents time, and the vertical axis represents respiratory flow. Although parameter values ​​can vary, typical breathing may have the following approximations: tidal volume Vt 0.5L, inhalation time Ti 1.6s, peak inspiratory flow Qpeak 0.4L / s, expiratory time Te 2.4s, peak expiratory flow Qpeak -0.5 L / s. Total duration of respiration. Ttot Approximately 4 seconds. Humans typically breathe at a rate of about 15 breaths per minute (BPM), with a ventilation volume of... Vent It is approximately 7.5 L / min. Typical duty cycle ( Ti and Ttot The ratio is approximately 40%.

[0297] 4.6 Glossary

[0298] To achieve the purposes of this technical disclosure, one or more of the following definitions may be applied in certain forms of this technology. Alternative definitions may be applied in other forms of this technology.

[0299] 4.6.1.1 Overview

[0300] Air In some forms of this technology, air may be considered to mean atmospheric air, and in other forms of this technology, air may be considered to mean some other combination of breathable gases, such as oxygen-enriched air.

[0301] environment In some forms of this technology, the term "environment" will be considered to mean (i) outside the treatment system or the patient, and (ii) directly surrounding the treatment system or the patient.

[0302] For example, the environment relative to a humidifier humidity This could be the humidity of the air directly surrounding the humidifier, such as the humidity inside the patient's bedroom. This ambient humidity can differ from the humidity outside the patient's bedroom.

[0303] In another example, environmental stress can be stress that directly surrounds the body or is located outside the body.

[0304] In some forms, ambient (e.g., acoustic) noise can be considered as the background noise level in the room where the patient is located, rather than noise generated, for example, by the RPT device or emitted from the mask or patient interface. Ambient noise may be generated by sources outside the room.

[0305] Automated Positive Airway Pressure (APAP) Therapy : Among them, CPAP therapy, in which the treatment pressure can be automatically adjusted between minimum and maximum (e.g., varying with each breath), depends on the presence of an indication for an SDB event.

[0306] Continuous positive airway pressure (CPAP) therapy This refers to respiratory pressure therapy, where the treatment pressure remains approximately constant throughout the patient's respiratory cycle. In some forms, the pressure at the airway inlet is slightly higher during expiration and slightly lower during inspiration. In other forms, the pressure will vary between different respiratory cycles, for example, increasing in response to an indication of partial upper airway obstruction and decreasing when no indication of partial upper airway obstruction is detected.

[0307] flow Flow rate refers to the volume (or mass) of air delivered per unit time. Flow rate can refer to an instantaneous quantity. In some cases, referring to flow rate will refer to a scalar quantity, that is, a quantity that only has a value. In other cases, referring to flow rate will refer to a vector quantity, that is, a quantity that has both a value and a direction. Flow rate can be represented by symbols. Q The term "flow" is sometimes simply abbreviated as "flow" or "airflow".

[0308] In the example of patient breathing, the flow rate can be nominally positive for the inspiratory portion of the patient's respiratory cycle and therefore negative for the expiratory portion. Device flow rate Qd This is the flow rate of air leaving the RPT unit. Total flow rate. Qt It is the flow rate of air and any supplemental gas reaching the patient interface via the air circuit. Ventilation flow rate Qv This is the flow rate of air leaving the vent to allow for flushing of exhaled air. Leakage flow rate. Ql This is the flow rate leaking from the patient interface system or elsewhere. Respiratory flow rate. Qr It is the flow rate of air received from the patient's respiratory system.

[0309] Flow therapy Breathing therapy involves delivering a flow of air to the inlet of the airway at a controlled flow rate known as the therapeutic flow, which is typically positive throughout the patient’s respiratory cycle.

[0310] humidifierThe term "humidifier" will be considered to refer to a humidifying device that is constructed and arranged or has a physical structure to provide a therapeutically beneficial amount of water (H2O) vapor to an airflow to alleviate a patient's medical respiratory symptoms.

[0311] leakage The term "leak" will be used to describe an unintended flow of air. In one instance, a leak might occur due to an incomplete seal between the mask and the patient's face. In another example, a leak might occur in a swivel bend leading to the environment.

[0312] Conducted (acoustic) noise Conducted noise, as used in this document, refers to noise transmitted to the patient through pneumatic paths, such as air circuits and patient interfaces, 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.

[0313] Radiated (acoustic) noise Radiated noise in this document refers to noise transmitted to the patient by ambient air. In one form, radiated noise can be quantified according to ISO 3744 by measuring the sound power / sound pressure level of the object in question.

[0314] Vent (acoustic) noise Ventilation noise in this document refers to the noise generated by the airflow through any ventilation opening, such as the ventilation hole of a patient interface.

[0315] Oxygen-rich air Oxygen-rich air is air with an oxygen concentration greater than that of atmospheric air (21%), for example, at least about 50% oxygen, at least about 60% oxygen, at least about 70% oxygen, at least about 80% oxygen, at least about 90% oxygen, at least about 95% oxygen, at least about 98% oxygen, or at least about 99% oxygen. "Oxygen-rich air" is sometimes shortened to "oxygen".

[0316] Medical oxygen: Medical oxygen is defined as oxygen-enriched air with an oxygen concentration of 80% or higher. patient People, regardless of whether they have respiratory illnesses.

[0317] pressure: Force per unit area. Pressure can be expressed in units, including cmH2O, gf / cm². 2 And 1000 pascals. 1 cmH2O equals 1 g-f / cm 2 And it is approximately 0.98 hectopascals (1 hectopascal = 100 Pa = 100 N / m). 2 = 1 millibar to 0.001 atm). In this specification, unless otherwise stated, pressure is given in cmH2O.

[0318] Pressure in the patient interface is represented by symbols Pm Give, and treat stress with symbols Pt The treatment pressure is given as the pressure transmitted through the interface at the current moment. Pm The target value achieved.

[0319] Respiratory pressure therapy Air supply is applied to the airway inlet at a therapeutic pressure that is normally positive relative to the atmosphere.

[0320] Ventilator Mechanical devices that provide pressure support to patients to perform some or all of their breathing tasks.

[0321] 4.6.1.2 Materials and their properties

[0322] Hardness: refers to the hardness of a hardness tester or indentation hardness, which is a material property measured by indentation through an indenter (e.g., as measured according to ASTM D2240).

[0323] "Soft" materials may include silicone or thermoplastic elastomers (TPEs) and may deform easily, for example, under finger pressure.

[0324] "Hard" materials can include polycarbonate, polypropylene, and can be, for example, not easily deformed under finger pressure.

[0325] Silicone or silicone elastomer Synthetic rubber. In this specification, reference to silicone refers to liquid silicone rubber (LSR) or compression-molded silicone rubber (CMSR). One commercially available form of LSR is SILASTIC (included in the range of products sold under this trademark), manufactured by Dow Corning. Another manufacturer of LSR is Wacker Chemie. Unless otherwise specified, exemplary forms of LSR have a Shore A (or Type A) indentation hardness in the range of about 35 to about 45 as measured using ASTM D2240.

[0326] polycarbonate : A thermoplastic polymer of bisphenol A carbonate.

[0327] 4.6.1.3 Mechanics

[0328] axis: a. Neutral axis: An axis in the cross-section of a beam or plate that has no longitudinal stress or strain.

[0329] b. Vertical axis: The axis that extends along the length of the shape. This axis usually passes through the center of the shape.

[0330] c. Circumferential axis: An axis oriented perpendicularly to the longitudinal axis. This axis can specifically exist in pipes, tubes, cylinders, or similar shapes with circular and / or elliptical cross-sections.

[0331] Deformation: The process by which the original geometry of a component changes when subjected to a force (e.g., a force relative to the direction along an axis). This process can include stretching or compression, bending, and twisting.

[0332] Elasticity: The ability of a material to return to its original geometry after deformation.

[0333] Flexible structures or components: Structures or components that will change shape (e.g., bend) when subjected to a relatively short period of time, such as 1 second, to support their own weight.

[0334] Resilience: The ability of a material to absorb energy during elastic deformation and release energy during unloading.

[0335] Elasticity: Releases virtually all of the energy upon unloading. Examples include certain silicones and thermoplastic elastomers.

[0336] Rigid structures or components: Structures or components that will not substantially change shape when subjected to loads typically encountered during use. An example of such use is, for instance, setting up and maintaining a sealed relationship between the patient interface and the inlet of the patient's airway under loads of approximately 20 to 30 cmH2O.

[0337] As an example, an I-beam may include a different bending stiffness (resistance to bending loads) in the first direction compared to the second orthogonal direction. In another example, the structure or component may be flexible in the first direction and rigid in the second direction.

[0338] Stiffness (or rigidity) of a structure or component: the ability of a structure or component to resist deformation in response to an applied load. The load can be a force or moment, such as compression, tension, bending, or torque. The structure or component can provide different resistance in different directions. The opposite of stiffness is flexibility.

[0339] Viscosity: The ability of a material to resist flow.

[0340] Viscoelasticity: The ability of a material to exhibit both elastic and viscous behavior during deformation.

[0341] Yield: The condition where a material, after being deformed, no longer returns to its original geometry.

[0342] 4.6.1.4 Respiratory cycle

[0343] Apnea: According to some definitions, apnea is considered to have occurred when the flow rate drops below a predetermined threshold for a sustained period of time (e.g., 10 seconds). Obstructive apnea is considered to occur when some obstruction of the airway prevents airflow even with patient effort. Central apnea is considered to occur when apnea is detected due to reduced or absent respiratory effort, even though the airway is patent. Mixed apnea is considered to occur when reduced or absent respiratory effort occurs simultaneously with airway obstruction.

[0344] Respiratory rate: The rate at which a patient breathes spontaneously, usually measured as the number of breaths per minute.

[0345] Duty cycle: The ratio of inspiratory time Ti to total respiratory time Ttot.

[0346] Effort (breathing): The work that a person who breathes spontaneously tries to do while breathing.

[0347] The expiratory portion of the respiratory cycle: the time period from the start of expiratory flow to the start of inspiratory flow.

[0348] Flow restriction: Flow restriction is considered a state of breathing in which increased effort by the patient does not result in a corresponding increase in flow. Airflow restriction occurring during the inspiratory portion of the respiratory cycle can be described as inspiratory airflow restriction. Flow restriction occurring during the expiratory portion of the respiratory cycle can be described as expiratory flow restriction.

[0349] Types of flow-limited inhalation waveforms: (i) Flat-topped: It rises first, followed by a relatively flat section, and then falls.

[0350] (ii) M-shape: has two local peaks, one at the leading edge and one at the trailing edge, and a relatively flat portion between the two peaks.

[0351] (iii) Chair-shaped: has a single local peak at the leading edge, followed by a relatively flat section.

[0352] (iv) Inverted chair shape: has a relatively flat section followed by a single local peak at the trailing edge.

[0353] Insufficient breathing: Under certain conditions, insufficient breathing is considered a reduction in flow, not an interruption of flow. In one form, insufficient breathing can be considered to have occurred when the flow rate drops below a threshold rate for a sustained period of time. Central insufficient breathing is considered to have occurred when insufficient breathing is detected due to reduced respiratory effort. In one form in adults, any of the following can be considered insufficient breathing: (i) The patient's breathing decreases by 30% for at least 10 seconds, plus an associated 4% desaturation; or (ii) The patient’s breathing is reduced (but less than 50%) for at least 10 seconds, accompanied by at least 3% associated desaturation or arousal.

[0354] Hyperventilation: The flow rate increases to a level higher than normal.

[0355] The inspiratory portion of the respiratory cycle: The time period from the start of inspiratory flow to the start of expiratory flow is considered the inspiratory portion of the respiratory cycle.

[0356] Openness (airway): The degree to which the airway is open or the degree to which the airway is open. An open airway is an open airway. Airway patency can be quantified, for example, a value of one (1) indicates patency, and a value of zero (0) indicates closure (obstruction).

[0357] Positive end-expiratory pressure (PEEP): The pressure above atmospheric pressure present in the lungs at the end of expiration.

[0358] Peak flow (Qpeak): The maximum flow rate during the inspiratory portion of the respiratory flow waveform.

[0359] Respiratory flow, patient airflow, and respiratory airflow rate (Qr): These terms can be understood as estimates of the respiratory flow rate of the RPT device, rather than “real respiratory flow rate” or “actual respiratory flow rate”, which is the actual respiratory flow rate experienced by the patient, usually expressed in liters per minute.

[0360] Tidal volume (Vt): The volume of air inhaled or exhaled during normal breathing without additional effort. In principle, the inspiratory volume Vi (the volume of air inhaled) equals the expiratory volume Ve (the volume of air exhaled), and therefore a single tidal volume Vt can be defined as equal to either volume. In practice, tidal volume Vt is estimated as some combination of inspiratory volume Vi and expiratory volume Ve, such as an average.

[0361] Inspiratory time (Ti): The duration of the inspiratory portion of the respiratory flow waveform.

[0362] Expiratory time (Te): The duration of the expiratory portion of the respiratory flow waveform.

[0363] Total Time (Ttot): The total duration between the start of one inspiratory portion of the respiratory flow waveform and the start of the next inspiratory portion of the respiratory flow waveform.

[0364] Typical recent ventilation: The recent value of ventilation tends to cluster around the ventilation value over a predetermined time range; that is, it is a measure of the central tendency of recent ventilation values.

[0365] Upper airway obstruction (UAO): This includes partial and complete upper airway obstruction. This may be associated with a state of flow restriction, where the flow rate increases only slightly or may even decrease as the pressure differential across the upper airway increases (Starling resistance behavior).

[0366] Ventilation: A measurement of the total amount of gas exchanged by a patient's respiratory system. Ventilation can be measured as either inspiratory or expiratory flow (per unit of time). When expressed as volume per minute, this amount is often referred to as "minute ventilation." Minute ventilation is sometimes simply given as volume and understood as volume per minute.

[0367] 4.6.1.5 Ventilation

[0368] Adaptive Servo Ventilator (ASV): A servo ventilator with a variable rather than a fixed target ventilation. The variable target ventilation can be determined based on a certain characteristic of the patient (e.g., the patient's respiratory characteristics).

[0369] Standby rate: A parameter of the ventilator that sets the minimum respiratory rate (usually measured in breaths per minute) that the ventilator will deliver to the patient if not triggered by spontaneous breathing effort.

[0370] Cyclic: Termination of the inspiratory phase of a ventilator cycle. When a ventilator delivers breaths to a spontaneously breathing patient, the ventilator cycle is considered to end at the end of the inspiratory portion of the respiratory cycle.

[0371] Positive expiratory airway pressure (EPAP): The base pressure to which the pressure changes within the respiratory tract to produce the desired interface pressure that the ventilator will attempt to achieve at a given time.

[0372] End-expiratory pressure (EEP): The desired interface pressure that the ventilator will attempt to achieve at the end of the expiratory phase. If the pressure waveform template Π(Φ) is zero at the end of expiration, i.e., Π(Φ) = 0 when Φ = 1, then EEP equals EPAP.

[0373] Inspiratory Positive Airway Pressure (IPAP): The maximum desired interface pressure that the ventilator will attempt to achieve during the inspiratory phase of breathing.

[0374] Pressure support: This refers to the pressure increase during inspiratory breathing that exceeds the pressure during expiratory breathing, and typically means the pressure difference between the maximum inspiratory pressure and the baseline pressure (e.g., PS = IPAP - EPAP). In some cases, pressure support refers to the difference the ventilator is designed to achieve, rather than the difference it actually achieves.

[0375] Servo ventilator: A ventilator that measures a patient’s ventilation volume, has a target ventilation volume, and adjusts the level of pressure support to enable the patient to achieve the target ventilation volume.

[0376] Spontaneous / Timed (S / T): A mode of operation for a ventilator or other device that attempts to detect the onset of spontaneous breathing in a patient. However, if the device fails to detect breathing for a predetermined period of time, it will automatically initiate the delivery of breaths.

[0377] Oscillation: A term equivalent to pressure support.

[0378] Triggering: A patient is considered to be triggered when a ventilator or other respiratory therapy device (such as an RPT device or portable oxygen concentrator) delivers a volume of breathable gas to a spontaneously breathing patient. Triggering typically occurs at or near the start of the breathing portion of a respiratory cycle, with the patient's effort.

[0379] 4.6.1.6 Shape of the structure

[0380] Products according to this technology may include one or more three-dimensional mechanical structures, such as a mask pad or impeller. The three-dimensional structure may be defined by two-dimensional surfaces. These surfaces may be distinguished using markings to describe associated surface orientation, location, function, or some other characteristic. For example, the structure may include one or more of a front surface, a rear surface, an inner surface, and an outer surface. In another example, the seal-forming structure may include a face-contact (e.g., outer) surface and separate non-face-contact (e.g., underside or inner) surfaces. In another example, the structure may include a first surface and a second surface.

[0381] 4.6.1.7 Curvature of a Two-Dimensional Surface

[0382] 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 multiple 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.

[0383] Principal curvature and principal direction: The directions in which the curvature of a curve in the normal plane reaches its maximum and minimum values ​​are called principal directions.

[0384] A region of a surface: a connected set of points on the surface. The set of points in a region may have similar properties, such as curvature or sign.

[0385] Saddle-shaped regions: regions where the principal curvature has opposite signs at each point, i.e., one sign is positive and the other is negative (depending on the direction the imagined person is turning, they can go up or down).

[0386] Vault region: The region where the principal curvature has the same sign at each point, such as two positive ("concave vault") or two negative ("convex vault").

[0387] Cylindrical region: A region with one principal curvature of zero (or, for example, zero within manufacturing tolerances) and another principal curvature of non-zero.

[0388] Planar region: A region of surface where both principal curvatures are zero (or, for example, zero within manufacturing tolerances).

[0389] Surface edge: The boundary or limit of a surface or region.

[0390] Path: In some forms of this technique, "path" will be considered to mean a path in a mathematical-topological sense, such as a continuous spatial curve from f(0) to f(1) on a surface. In some forms of this technique, "path" may be described as a route or road, including, for example, a set of points on a surface. (An imagined path for a person is where they walk on the surface, and is similar to a garden path).

[0391] Path length: In some forms of this technique, "path length" will be considered as the distance along the surface from f(0) to f(1), i.e., the distance along a path on the surface. There can be more than one path between two points on the surface, and such paths can have different path lengths. (The path length for an imagined person would be the distance they must walk along the path on the surface.)

[0392] Straight-line distance: Straight-line distance is the distance between two points on a surface, but without considering the surface itself. On a planar surface, there will exist a path with the same length as the straight-line distance between the two points. On a non-planar surface, there may not be a path with the same length as the straight-line distance between the two points. (For the imaginary reader, straight-line distance will correspond to the distance as a "straight line".)

[0393] Tangent unit vector (or unit tangent vector): For each point on a curve, the vector at that point specifies the direction and magnitude of travel from that point. The tangent unit vector is a unit vector pointing in the same direction as the curve at that point. If you imagine a person flying along a curve and falling from their aircraft at a specific point, the direction of the tangent vector is the direction they would have traveled.

[0394] Unit normal vector: This tangent vector changes as an imagined person moves along the curve. The unit vector pointing in the direction of change of the tangent vector is called the principal normal vector. It is perpendicular to the tangent vector.

[0395] Double normal unit vector: A double normal unit vector is perpendicular to both the tangent vector and the principal normal vector.

[0396] Oscillating plane: A plane containing a unit tangent vector and a unit principal normal vector.

[0397] Torque of a space curve: The torque at a point on a space curve is the magnitude of the rate of change of the unit vector of the binormal at that point. It measures the degree to which the curve deviates from the osculating plane. A space curve lying in the osculating plane has zero torque. A space curve deviating relatively small from the osculating plane will have a relatively small torque (e.g., a gently sloping spiral path). A space curve deviating relatively large from the osculating plane will have a relatively large torque (e.g., a sharply sloping spiral path).

[0398] 4.7 Other Notes

[0399] This patent document contains a portion of copyrighted material. The copyright holder does not object to any fax reproduction of the patent document or patent disclosure appearing in the patent office's patent documents or records, but otherwise reserves all copyright rights.

[0400] Unless the context clearly indicates otherwise and where a range of values ​​is provided, it should be understood that every intermediate value between the upper and lower limits of the range (to one-tenth of the lower limit unit), and any other stated or intermediate value within the stated range, is included within this technology. The upper and lower limits of these intermediate ranges (which may be independently included in the intermediate range) are also included within this technology, but are subject to any express exclusions within the stated range. Where the stated range includes one or both of these limitations, the range excluding any one or both of those included limitations is also included within this technology.

[0401] Furthermore, in cases where one or more values ​​stated herein are implemented as part of this technique, it should be understood that such values ​​may be approximate unless otherwise stated, and such values ​​may be used to the extent permitted or required by the practical technical implementation of any appropriate number of digits.

[0402] In addition, as used herein, “approximately,” “substantially,” “about,” or any similar terms mean + / - 5% to 10% of the listed values.

[0403] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this technology pertains. While any methods and materials similar to or equivalent to those described herein may be used in the practice or testing of this technology, a limited number of exemplary methods and materials are described herein.

[0404] When a particular material is identified for use in constructing a component, an obviously alternative material with similar properties may be used as a substitute. Furthermore, unless otherwise stated, any and all components described herein are to be understood as being capable of being manufactured, and therefore may be manufactured together or separately.

[0405] It must be noted that, as used herein and in the appended claims, the singular forms “a” and “the” include their plural equivalents, unless the context clearly indicates otherwise.

[0406] All publications mentioned herein are incorporated herein by reference in their entirety to disclose and describe the methods and / or materials that are the subject of those publications. The publications discussed herein are provided solely for their disclosure prior to the filing date of this application. This document should not be construed as an admission that the present technology is not entitled to any prior disclosure due to a prior invention. Furthermore, the publication dates provided may differ from the actual publication dates, which may require independent verification.

[0407] The terms “comprises” and “comprising” should be understood as referring to each element, component, or step in a non-exclusive manner, indicating the marked element, component, or step that may be present or utilized, or a combination with other unmarked elements, components, or steps.

[0408] The headings used in the detailed description are for the convenience of the reader only and should not be used to limit the subjects that can be found in this disclosure or throughout the claims. These headings should not be used to interpret the scope or limit of the claims.

[0409] Although the techniques described herein have been illustrated with reference to specific examples, it should be understood that these examples are merely illustrative of the principles and applications of the techniques. In some cases, terms and symbols may imply specific details that are not required for practicing the techniques. For example, although the terms “first” and “second” may be used, they are not intended to indicate any order unless otherwise stated, but rather to distinguish different elements. Furthermore, although process steps in a method may be described or illustrated in sequence, such order is not required. Those skilled in the art will recognize that such ordering may be modified and / or aspects may be performed concurrently or even synchronously.

[0410] Therefore, it should be understood that various modifications can be made to the exemplary examples and other arrangements can be designed without departing from the spirit and scope of this technology.

Claims

1. A flow generating device for generating a breathable gas flow under positive pressure for respiratory therapy, the flow generating device comprising: A housing having an inlet and an outlet; A blower, comprising a motor and an impeller, for drawing ambient gas into the housing through the inlet and discharging it from the housing through the outlet; and At least one silencing device comprising a nonwoven fabric, the silencing device being lined or partially lined on one or more internal surfaces of the housing or within the housing.

2. The flow generation device according to claim 1, wherein the silencing device is entirely formed of synthetic materials.

3. The flow generating device according to any one of claims 1 or 2, wherein the nonwoven fabric of the silencing device is configured to include at least two opposing outer surfaces, the two opposing outer surfaces being spaced apart and connected by at least one sidewall.

4. The flow generating apparatus of claim 3, wherein the nonwoven fabric is configured to be bent into a shape about an axis parallel to one outer surface of the nonwoven fabric.

5. The flow generation apparatus of claim 3, wherein the nonwoven fabric is configured to be bent into a shape about an axis perpendicular to the surface of the nonwoven fabric.

6. The flow generating device according to any one of claims 1 to 5, wherein the housing comprises a plurality of chambers, at least one of the chambers comprising at least one silencer and at least one flow limiter.

7. The flow generating apparatus according to any one of claims 1 to 6, wherein the apparatus is configured to define a gas flow path between the inlet and the outlet of the housing, and the silencing device is at least partially located within the gas flow path.

8. The flow generating device according to any one of claims 1 to 7, wherein the inner surface of the housing includes one or more flanges, recesses, orifices, channels, notches, or hooks configured to receive the at least one silencing device.

9. The flow generating device according to any one of claims 1 to 8, wherein the silencing device comprises at least one integrally formed flange, recess, orifice, channel, notch, hook, or adhesive configured to allow the silencing device to be attached to the inner surface of the housing of the device.

10. The flow generation device according to any one of claims 1 to 9, wherein the silencing device is partially or completely encapsulated by a frame.

11. The flow generation apparatus of claim 10, wherein the frame portion is an overmolded edge.

12. The flow generation device of claim 11, wherein the frame portion comprises a porous support.

13. The flow generation apparatus of claim 12, wherein the frame portion includes a front panel of a porous support and an opposing rear panel of the porous support, the front panel and the rear panel of the porous support being connected and spaced apart by at least one sidewall, the nonwoven fabric being positioned between the front panel and the rear panel of the porous support, the periphery of the nonwoven fabric being surrounded by the at least one sidewall of the frame portion.

14. The flow generation apparatus of claim 13, wherein the porous support is configured to define an orifice in the support, the cross-sectional area of ​​the orifice being 4 mm² when the cross-section is measured substantially parallel to the nonwoven fabric. 2 Up to 10000mm 2 .

15. The flow generating apparatus according to any one of claims 10 to 14, wherein the frame portion includes at least one retaining feature configured to releasably retain the silencing device within the housing.

16. The flow generating apparatus according to any one of claims 1 to 15, wherein the silencing device is made of a single material.

17. The flow generation apparatus according to any one of claims 1 to 16, wherein the nonwoven fabric is a needle-punched nonwoven fabric, a melt-blown nonwoven fabric, a spunbond nonwoven fabric, a hydroentangled nonwoven fabric, and / or a flash-steamed nonwoven fabric.

18. The flow generation apparatus according to any one of claims 1 to 17, wherein the nonwoven fabric is formed using thermal bonding, hydroentanglement, ultrasonic pattern bonding, needle punching, and / or chemical bonding.

19. The flow generating apparatus according to any one of claims 1 to 18, wherein the nonwoven fabric of the silencing device comprises at least one heat-treated surface to reduce fiber migration from the nonwoven fabric.

20. The flow generation apparatus of claim 19, wherein the nonwoven fabric comprises two opposing heat-treated surfaces.

21. The flow generation apparatus according to claim 19 or 20, wherein the heat-treated surface is formed by calendering the surface of the nonwoven fabric at 120°C to 170°C.

22. The flow generating apparatus according to any one of claims 1 to 21, wherein the nonwoven fabric comprises two opposing outer surfaces having different surface textures, surface roughness, or profiles from each other.

23. The flow generating apparatus according to any one of claims 1 to 22, wherein the nonwoven fabric has a denier number (D) of 3 to 15.

24. The flow generating apparatus according to any one of claims 1 to 23, wherein the density of the nonwoven fabric is from 50 kg / m³ to 200 kg / m³.

25. The flow generating apparatus according to any one of claims 1 to 24, wherein the porosity of the nonwoven fabric is between 50% and 90%.

26. The flow generating apparatus according to any one of claims 1 to 25, wherein the nonwoven fabric is made of one or more pieces or one or more nonwoven fabrics with a thickness between 1 mm and 20 mm.

27. A noise reduction device comprising a nonwoven fabric adapted to attenuate and / or deflect sound waves within the housing of the device, the device being used to supply a flow of breathable gas under positive pressure for respiratory therapy.

28. The silencing device of claim 27, wherein the nonwoven fabric of the silencing device is configured to include at least two opposing outer surfaces, the two opposing outer surfaces being spaced apart and connected by at least one sidewall.

29. The silencing device of claim 28, wherein the nonwoven fabric is configured to be bent into a shape about an axis parallel to one outer surface of the nonwoven fabric.

30. The silencing device of claim 28, wherein the nonwoven fabric is configured to be bent into a shape about an axis perpendicular to the surface of the nonwoven fabric.

31. The silencing device according to any one of claims 27 to 30, wherein the silencing device comprises or is shaped to define at least one integrally formed flange, recess, orifice, channel, notch, hook, or adhesive.

32. The silencing device according to any one of claims 27 to 31, wherein the silencing device is partially or completely encapsulated by a frame.

33. The silencing device of claim 32, wherein the frame portion includes an overmolded edge.

34. The silencing device according to claim 32 or 33, wherein the frame portion comprises a porous support.

35. The silencing device of claim 34, wherein the frame portion includes a front panel of a porous bracket and an opposing rear panel of the porous bracket, the front panel and the rear panel of the porous bracket being connected and spaced apart by at least one sidewall, the nonwoven fabric being positioned between the front panel and the rear panel of the porous bracket, the periphery of the nonwoven fabric being surrounded by the at least one sidewall of the frame portion.

36. The silencing device according to claim 34 or 35, wherein the porous support is configured to define an orifice in the support, the cross-sectional area of ​​the orifice being 2 mm² when the cross-section is measured substantially parallel to the nonwoven fabric. 2 Up to 20mm 2 .

37. The silencing device according to any one of claims 32 to 36, wherein the frame portion includes at least one retaining feature, the at least one retaining feature being connectable to a connecting member on a separate device or equipment.

38. The silencing device according to any one of claims 27 to 37, wherein the silencing device is made of a single material.

39. The silencing device according to any one of claims 27 to 38, wherein the nonwoven fabric is a needle-punched nonwoven fabric, a melt-blown nonwoven fabric, a spunbond nonwoven fabric, a spunlace nonwoven fabric, and / or a flash-spun nonwoven fabric.

40. The silencing device according to any one of claims 27 to 39, wherein the nonwoven fabric is formed using thermal bonding, hydroentanglement, ultrasonic pattern bonding, needle punching, and / or chemical bonding.

41. The silencing device according to any one of claims 27 to 40, wherein the nonwoven fabric of the silencing device comprises at least one calendered surface.

42. The noise reduction device of claim 41, wherein the nonwoven fabric includes two opposing calendered surfaces for reducing fiber migration from the nonwoven fabric.

43. The silencing device according to claim 41, wherein at least one calendered surface is formed by calendering the surface of the nonwoven fabric at a temperature of 120°C to 170°C.

44. The silencing device according to any one of claims 27 to 43, wherein the silencing device comprises two opposing surfaces having different surface textures, surface roughness, or profiles from each other.

45. The silencing device according to any one of claims 27 to 44, wherein the nonwoven fabric has a denier number (D) of 3 to 15.

46. ​​The silencing device according to any one of claims 27 to 45, wherein the density of the nonwoven fabric is from 50 kg / m³ to 200 kg / m³.

47. The silencing device according to any one of claims 27 to 46, wherein the porosity of the nonwoven fabric is between 50% and 90%.

48. The silencing device according to any one of claims 27 to 47, wherein the nonwoven fabric is made of one or more pieces of nonwoven fabric with a thickness between 1 mm and 20 mm.

49. The silencing device according to claim 48, wherein the nonwoven fabric comprises multiple layers of nonwoven fabric of different sizes, the multiple layers of nonwoven fabric of different sizes being laminated together to form an irregularly shaped silencing device.

50. The silencing device according to any one of claims 27 to 49, wherein the device includes one or more shaped, molded, or textured outer surface regions to increase the surface area of ​​the silencing device.

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