83 results about "Inhalation Valve" patented technology

The present invention relates to the technical field of respiratory training equipment, and in particular to a respiratory training device, comprising a mouthpiece, a shell, an exhalation valve, and an inhalation valve, wherein the mouthpiece is connected to the shell and is provided with mutually connected airways inside; at least two concave cavities are provided on the outer wall of the shell, and vents are provided on the bottom wall of the concave cavity of the shell and the vents are connected with the airways, and a valve cover is provided on each concave cavity, and the valve cover is threadedly connected to the shell at the corresponding position of the concave cavity, and the valve cover is connected to the shell by rotating the thread to change the size of the area of ​​the concave cavity connected with the outside, and a one-way valve sheet is provided on the shell corresponding to the air vent, and the one-way valve sheet is used to limit the direction of the airflow through the vent. A respiratory training device obtained by the present invention realizes independent adjustment of the inhalation resistance and the exhalation resistance to enhance the strength and endurance of the expiratory muscles and the inspiratory muscles (diaphragm and intercostal muscles).

A combined one way inspiratory valve and expiratory release valve assembly is provided for controlling air flow in a respiratory treatment system. The valve assembly comprises a housing comprising a valve inlet, a valve outlet and at least one vent opening, and a diaphragm sealingly connected to the housing at an outer circumference of the diaphragm, wherein the diaphragm divides the housing into; a) an upstream portion, which is in fluid communication with the valve inlet, and b) a downstream portion which is in fluid communication with the valve outlet. The diaphragm has a circular, oval, elliptical or stadium shape. An inner portion of the diaphragm defines a one way inspiratory valve. An outer portion of the diaphragm defines an expiratory release valve. A method of characterising vent flow in a respiratory treatment system which includes such a valve is also described.

The utility model relates to a burning-resistant fire-retardant breather valve which comprises a valve body, a fire arrester connecting flange is fixedly connected to the top of the outer side wall of the valve body, a fire arrester is installed on the fire arrester connecting flange, a fixing plate is fixedly connected to the bottom wall of the valve body, and a guide cylinder is fixedly connected to the bottom wall of the fixing plate. A flange base is fixedly connected to the bottom wall of the guide cylinder, a supporting cylinder is fixedly connected to the upper wall of the fixing plate located in the valve body, an exhalation valve disc assembly is arranged on the upper wall of the supporting cylinder, an inhalation valve disc assembly is connected to the exhalation valve disc assembly, and a supporting column is fixedly connected to the inner wall of the guide cylinder. A valve rod fixedly penetrates through the middle of the supporting column. Compared with the prior art, the device has the advantages that the occupied space and the weight are greatly reduced, the cost is saved, and the pressure of the storage tank can be automatically adjusted when the pressure of the storage tank is too large or too small, so that the storage tank is prevented from being damaged.

The utility model belongs to the technical field of emergency rescue, and particularly relates to an air respirator mask and a system. The air respirator mask comprises a mask body and a transparent face mirror, a mouth and nose mask is arranged in an inner cavity of the mask body, an air circulation area is formed between the outer portion of the mouth and nose mask and the inner side of the face mirror, two air suction valve plates are symmetrically arranged on the mouth and nose mask, and a double-mouth breathing seat is arranged on the face mirror. The double-port breathing seat is provided with an inspiration valve connector and an exhalation valve connector, the inspiration valve connector is used for being connected with an air respirator air bottle and an air supply valve of the air respirator air bottle, and the inspiration valve connector is used for being connected with an exhalation valve seat which can be freely inserted and detached. By designing the double-port breathing seat and the exhalation valve seat capable of being freely inserted and detached, when gas in air exhalation is completely consumed, on the premise that an air respirator mask and an air supply valve of the air respirator mask are not detached, the exhalation valve seat is pulled out, and a chemical oxygen respirator is inserted into an exhalation valve interface, so that closed-loop type oxygen support can be provided for a wearer; and the respiratory protection time of rescuers is prolonged.

The invention relates to the technical field of medical instruments and digital health, in particular to an intelligent device of a child respiratory training device and a using method thereof, and the intelligent device comprises a silica gel nozzle, a plastic inlet piece, a mode disc, a silica gel suction valve, an adjusting spring, a frequency ball, an airway cavity, a strength disc, a detection module, an air inlet and outlet grating, a spring sliding piece, a silica gel exhalation valve and a mapping system; the mapping system comprises a self-adaptive algorithm module and a game mapping module. The self-adaptive algorithm module is used for calculating a gear and a training mode required by a user based on personal information of the user; the game mapping module sets a game scene and a training feedback mode based on breathing training of a user. The breathing mode and the training intensity are adjusted through a pure mechanical structure, the problem of insufficient user compliance is solved by combining breathing training with a game dynamic mapping engine, and the problem of individual difference is solved through a self-adaptive algorithm.

The invention relates to a device for automatically pressing a breathing balloon. The device comprises a mask, an exhalation valve, an inhalation valve, the breathing balloon, a three-way pipe, a pulling piece strip and a main controller. The mask is fixed to the face of a patient through the tearing adhesive tape and used in cooperation with the exhalation valve and the inhalation valve to form a breathing loop. The exhalation valve and the inhalation valve are both connected with the three-way pipe, a detection chip is arranged in the three-way pipe, the ventilation capacity is detected through the air pressure and the flow speed, and data can be sent to the main controller through wireless radio frequency signals; the pulling sheet strip is wound outside the breathing balloon, a main controller is fixed at one end of the pulling sheet strip, a transmission gear is arranged at the bottom end of the main controller and connected with the pulling sheet strip, the three-way pipe is provided with an air inlet, an air outlet and a pressure tapping port, and the pressure tapping port is connected with a pressure sensor of the breathing balloon. Compared with the prior art, the pressing force can be accurately guaranteed, and the pressing ventilation capacity can be guaranteed; the universality is realized; and meanwhile, clinging and regular pressing of the mask are ensured.

The utility model discloses a medicine suction bottle for nebulization therapy, which relates to the technical field of medical instruments and comprises a bottle body, a detachable base is arranged on one side of the bottle body, a large whistle and a small whistle are mounted on the base, an air suction valve is arranged on the other side of the bottle body, a suction nozzle is sleeved outside the air suction valve, and the suction nozzle is sleeved outside the bottle body. An air valve support, an air valve block installed on the air valve support and an air valve cover arranged outside the air valve support in a sleeving mode are further arranged on one side of the suction nozzle, a cover cap is connected to one side of the suction nozzle, and a medicine feeding cavity is formed in the bottle body. Due to the fact that the inhalation valve of the duck tongue valve structure is arranged on one side of the bottle body, a patient inhales from the position of the suction nozzle during use, the inhalation valve can be opened under the action of pressure, the inhalation valve is closed under the action of pressure during exhalation, and air is exhausted from an exhaust mechanism composed of the air valve support, the air valve block and the air valve cover. The device is simple and reasonable in structure, convenient to use during medicine suction and good in use effect.

The utility model relates to the technical field of semiconductor manufacturing, in particular to a breather valve and a semiconductor temperature control device, the breather valve comprises a shell, the shell is provided with an inner cavity, a first through hole and a second through hole, and the first through hole and the second through hole are respectively communicated with the inner cavity; the air suction valve plate is arranged in the first through hole and is movably connected with the shell through a first adjusting component; the exhalation valve plate is arranged in the second through hole and is movably connected with the shell through a second adjusting part; the breather valve is suitable for being switched between an inspiration state and an expiration state, in the inspiration state, the inspiration valve plate opens the first through hole, the expiration valve plate closes the second through hole, in the expiration state, the inspiration valve plate closes the first through hole, and the expiration valve plate opens the second through hole. When the breathing valve is applied to the circulating liquid system of the semiconductor temperature control device, the breathing function of the circulating liquid system can be realized by arranging the breathing valve capable of simultaneously meeting the requirements of high and low temperature areas through a special structural design, the customization cost is reduced, the structure is simple, and the stability of the circulating liquid system is improved.

The invention discloses a ventilation device (200), a control method of the ventilation device (200) and a computer storage medium. The ventilation device (200) comprises a driving module (201), a breathing circuit (202) and a ventilation control module (203). The ventilation control module (203) controls the driving module (201) to provide ventilation support for a patient through the breathing circuit (202); the breathing circuit (202) comprises an inspiration branch (2021) and an expiration branch (2022); the inspiration branch (2021) is provided with an inspiration valve, and the expiration branch (2022) is provided with an expiration valve; when the ventilation control module (203) is in a double-tube oxygen therapy mode, the exhalation valve is controlled to be closed, the inhalation valve is controlled to be opened, and oxygen-enriched gas is output through the inhalation branch (2021).

The utility model relates to a respiratory protection mask provided with a sealing self-checking device, and belongs to the technical field of respiratory protection sealing detection of protection masks. The sealing self-checking device is composed of a mask body, an elastic key, an inspiration valve seat channel, an inspiration valve, a filtering element connector, an air channel and a locking ring, the elastic key made of silica gel or rubber materials is adopted to press and block an air inlet channel, and due to the fact that the elastic key is soft, the plane contact sealing effect of the elastic key and the inspiration valve seat channel is good after the elastic key is pressed; after pressing, the fingers are released to restore the original shape, and the operation is convenient; the device can be suitable for breathing protection masks such as full face masks, half masks, single-filtering-element connectors and double-filtering-element connectors. The defects that in the prior art, detection illusion is easily caused by a self-detection method of blocking an air inlet by hands, and an airtight detection cover plate needs to be closed by driving a hinge to rotate through a pull rod in a manner of adopting the airtight detection cover plate, operation is inconvenient, a user feels oppressed when closing the airtight detection cover plate, and the airtight detection cover plate needs to be pressed down again to return are overcome.

The application discloses a training mask for COPD patients, and relates to the technical field of medical devices.The training mask comprises a mask body, a one-way inhalation valve arranged on the left side of the mask body, an oxygen access port arranged on the right side of the mask body, a thread structure arranged on the oxygen access port, an adjustable anti-resistance exhalation module arranged at the front end of the mask body, and a resistance adjusting knob arranged on the side of the adjustable anti-resistance exhalation module.The adjustable anti-resistance exhalation module is matched with the resistance adjusting knob and a variable resistance valve sheet, so that multi-stage adjustment of exhalation resistance is realized, the training needs of different patients and different disease stages are met, and the pertinence and effectiveness of the training are improved.The training mask is integrated with a cough auxiliary triggering module, a gear shifting knob and a manual gear adjusting mechanism, so that quick switching between a training gear and a cough gear is realized, the exhalation resistance can be instantaneously reduced during the cough training, the patients can complete effective cough actions, and the airway clearance ability is improved.

The present application provides a pulse oxygen supply system and a pulse oxygen supply control method, which relate to the technical field of oxygen supply for medical care. In the present application, the working hole of a first normally closed two-way three-way solenoid valve is communicated with an oxygen inhalation pipeline having a one-way inhalation valve of a closed-type breathing mask, the oxygen outlet of an oxygen supply unit is communicated with the air source hole of the first normally closed two-way three-way solenoid valve, and the air outlet of a positive pressure air supply unit is communicated with the exhaust hole of the first normally closed two-way three-way solenoid valve through a flow detector. Then, according to the gas flow condition detected by the flow detector during the human inhalation stage, the control unit controls the oxygen supply unit to supply oxygen during the human inhalation stage when the first normally closed two-way three-way solenoid valve is energized, and controls the positive pressure air supply unit to supply pressure-maintaining air during the human exhalation stage when the first normally closed two-way three-way solenoid valve is de-energized, so as to effectively reduce the oxygen supply cost in a high-pressure or slightly high-pressure oxygen inhalation environment, and simultaneously improve the oxygen utilization rate and the oxygen inhalation safety.

The utility model belongs to the technical field of inspiration valves, in particular to a detachable inspiration valve of a first-aid transfer respirator, which comprises an inspiration branch seat mounted on the inner wall of a left shell, a mounting groove is formed in the inner wall of the left shell in a penetrating manner, a one-way valve support is arranged in the mounting groove, and an INSP joint is arranged on one side of the one-way valve support; according to the utility model, the INSP joint is detachably connected with the INSP knob and the left side shell respectively, so that when the INSP joint needs to be disinfected, the INSP joint can be separated out by separating the INSP joint and the INSP knob from the left side shell, and further the INSP joint and internal parts can be cleaned and disinfected conveniently; by means of the structure, when the INSP connector is used, the situation that due to the fact that the INSP connector is directly fixed to the left side shell, the INSP connector cannot be fully disinfected and sterilized after being used for multiple times for a long time, bacteria breeding and unnecessary infection are caused, the normal using effect of a user is affected, and even harm is caused to the body is avoided.

Devices, systems, and methods for a suction valve assembly for a medical device. The suction valve (300) assembly includes a valve body (320), a sliding shaft (310), and a flap seal (340). The valve body has a central channel (322) extending vertically between vent openings (324) in the top and a working opening (326) in the bottom and a side opening (328) extending from the central channel to the side surface. The sliding shaft moves within the central channel between an upper position where its upper channels are adjacent the vent openings, and a lower position where it extends into the working opening and unseats the flap seal.

According to the deodorization floor drain, the interior of a base is divided into a first cavity and a second cavity through a partition plate, the first cavity is used for being connected with a water inlet pipe of a water using device, and the second cavity is used for being connected with a drainage pipe; a ground water inlet pipe is connected above the base, an air suction valve is arranged between the ground water inlet pipe and the base, and the two ends of the air suction valve are communicated with the second cavity and the ground water inlet pipe respectively. Therefore, the structure provided by the utility model can prevent the water inlet pipe of the water using device from reflecting odor, prevent the ground water inlet pipe from reflecting odor, and prevent the water seal structure from being damaged due to the siphon effect of the drain pipe.

The utility model discloses a suction valve and a breathing machine. The suction valve comprises an electromagnetic valve, a suction valve body, a gas circuit module and a safety valve. The suction valve body comprises a mounting seat, an air inlet passage and a valve port sealing piece; the installation seat and the suction valve body are integrally formed, one end of the air inlet channel is communicated with the air inlet, the valve port sealing piece abuts against the other end in the air inlet channel, a valve body air outlet is formed in one side of a cavity of the suction valve body, and a first air cavity is formed among the inner cavity wall of the suction valve body, the valve body air outlet and the one-way valve. A safety valve is installed on a suction valve of an airway of the breathing machine, a bypass air path is added, air enters the airway from the bypass air path through opening and closing of the safety valve, the air pressure in the airway is balanced when the pressure in the airway is too high, and it is guaranteed that the pressure of the conveyed air is within the safety range; air enters the air path through the safety valve ventilation branch to supplement air in the air path, so that sufficient air is ensured to pass through the lung of the patient, and the suffocation risk is avoided.

A kind of breathing valve for facilitating online monitoring, including valve body, setting and exhalation valve assembly and inhalation valve assembly in valve body, the exhalation valve assembly and inhalation valve assembly all include valve seat, valve disc and guide rod, the valve body top is fixedly connected with valve cover, the inside of the valve cover is equipped with the movement channel for accommodating guide rod lifting, the top of the valve cover is equipped with proximity switch sensor, the proximity switch sensor is electrically connected with external monitoring center by electric connection line or wireless connection, the guide rod is close to or away from proximity switch sensor by lifting action in movement channel, the proximity switch sensor sends guide rod distance change to monitoring center after sensing.

A ventilator (100) ventilates a patient (102) by a high-flow oxygen therapy via a tube system (104). The ventilator has at least one sensor element (110), at least one actuatable inhalation valve or exhalation valve (120) and a control unit (130). The sensor element is arranged and configured to determine and to output a measured variable (112) within the tube system. The measured variable indicates a gas flow within the tube system. The actuatable inhalation valve or exhalation valve is arranged and configured to make possible a flow of a breathing gas from a ventilation circuit (107) of the ventilator. The control unit regulates a ventilation pressure provided by the ventilator via the at least one sensor element and the at least one inhalation valve or exhalation valve such that a predefined maximum pressure is not exceeded in a predefined area (140) of the tube system.

The invention relates to a component with an inhalation valve for a breathing system, the component comprising: an inhalation opening of the inhalation valve for the flow of breathing gas into a pressure chamber in order to provide breathing gas in the pressure chamber for breathing of a patient, a closing element of the inhalation valve, the closing element being movably arranged in order to close the inhalation opening for the flow in a closed position and to at least partially open it in an open position, a transmission device of the inhalation valve, the transmission device being connected to the closing element via a connecting element in order to keep the closing element in the closed position in an initial position of the transmission device, preferably thereby providing the inhalation valve as a normally closed inhalation valve for the breathing system, a control pressure source for providing a control pressure to the transmission device in a control pressure chamber in order to move the transmission device from the initial position by the control pressure.

The invention relates to a waterproof breathable structure and a gauge pressure sensor, and relates to the technical field of pressure detection. The waterproof ventilation structure comprises a first shell, an exhalation valve and an inhalation valve, wherein the exhalation valve is in one-way communication from inside to outside only when the inner and outer pressure difference is larger than first opening pressure (P1), and the inhalation valve is in one-way communication from outside to inside only when the outer and inner pressure difference is larger than second opening pressure (P2). The first shell is provided with an inner cavity and a ventilation channel communicating the inner cavity with the environment. Reliable waterproof and dustproof protection can be achieved, the change of internal and external pressure difference can be quickly responded, and pressure balance is carried out.

The invention relates to the technical field of biochemical protection, in particular to a mask connector base structure for a gas mask, which comprises a tank body, and the inner wall of the tank body is provided with threads to serve as a tank connector for being connected with a gas filter tank; a center hole penetrates through the center of the inner bottom surface of the tank body, a circle of vent holes are formed in the periphery of the center hole, a gasket limiting groove is formed in the edge of the inner bottom surface of the tank body, and a plurality of rectangular grooves are formed in the gasket limiting groove; an air suction valve piece covering the vent hole is installed on the outer side of the bottom face of the tank body through a rivet, and the rivet is fixedly connected to the center hole. The gas mask gasket is reasonable in design, the gasket can be effectively prevented from falling off, the use reliability of a gas mask is improved, the daily guarantee difficulty of the gas mask is reduced, and the gas mask gasket has good practical application value.

A piston (18) of a compressor (1) partitions the inside of a cylinder (17) into a compression chamber (21) and a suction chamber (22). A communication passage (19A) is formed in the piston (18). The communication passage (19A) establishes communication between the compression chamber (21) and the suction chamber (22). The suction valve (23) opens and closes an opening (19A1) of the communication passage (19A). The suction valve (23) has a plate-like shape. The suction valve (23) includes a fixation portion (23A) fixed to the piston (18), a closing portion (23B) configured to cover the opening (19A), and a spring portion (23C) connecting the fixation portion (23A) and the closing portion (23B). A spring portion facing portion (19B) in the piston (18), which faces the spring portion (23C) of the suction valve (23), is recessed more deeply than a closing portion facing portion (19C), which faces the closing portion (23B) of the suction valve (23).

The utility model relates to the technical field of breather valves, in particular to a breather valve convenient to replace, which comprises an exhalation valve body and an inspiration valve body which are fixedly communicated through a communicating pipe, a pressure relief opening and an inspiration opening are respectively arranged on the exhalation valve body and the inspiration valve body, and an exhalation valve cover and an inspiration valve cover are respectively matched at the pressure relief opening and the inspiration opening in a sliding mode. The exhalation valve cover and the inspiration valve cover are connected with the exhalation valve body and the inspiration valve body through a first elastic mechanism and a second elastic mechanism respectively, and a plurality of communicating exhalation ring grooves capable of enabling the pressure relief opening to be communicated are formed in the side, close to the exhalation valve body, of the exhalation valve cover at intervals. Therefore, the telescopic filter cover can be conveniently replaced in a state of avoiding air suction in a running state, and no impurities are sucked in the replacement process in the running state.

A device, system, and method for a suction valve assembly for a medical device. The suction valve assembly includes a valve member having a valve shaft that slides within a valve well. The valve shaft includes one or more slits and is biased to expand outward and compress the inner wall of the valve well.

The embodiment of the present application discloses a safety valve, an inhalation valve and a breathing machine, wherein the safety valve comprises a mounting seat, a closing assembly and a driving assembly. The mounting seat is provided with a ventilation channel; the elastically connected closing assembly has a first position capable of closing the ventilation channel and a second position capable of opening the ventilation channel on the mounting seat; in a free state, the elastic force forces the closing assembly to be located at the first position or the second position; the driving assembly can drive the closing assembly to move against the elastic force, so that the closing assembly is transformed between the first position and the second position. By setting the closing assembly, the closing assembly is elastically connected to the mounting seat; in a free state, the closing assembly can be located at the first position capable of closing the ventilation channel or at the second position capable of opening the ventilation channel under the action of the elastic force; by cooperation of the driving assembly and the elastically arranged closing assembly, the opening and closing of the ventilation channel can be realized, the structure is simple, the cost is reduced, and assembly is relatively convenient.

Embodiments of the present application disclose a compliance and leakage determination method and device, equipment and a storage medium, the method is applied to a breathing assistance system including at least a gas flow pipeline provided with an inhalation valve, the method comprises: obtaining real-time flow rate flowing through the inhalation valve and simulation breathing data, the simulation breathing data includes inhalation data and exhalation data; the inhalation data includes inhalation start time and inhalation end time, and the exhalation data includes exhalation start time and exhalation end time; determining pipeline compliance of the gas flow pipeline by using the real-time flow rate, the inhalation start time, the inhalation end time, the exhalation start time and the exhalation end time; and determining system leakage of the breathing assistance system by using the exhalation start time and the inhalation start time. Through the above manner, the self-checking of the leakage and compliance of the breathing assistance system can be realized without using high-precision flow sensors and flow control valves, and the cost is effectively reduced.

The utility model is applicable to the technical field of breathing machines, and provides an inspiration valve for a breathing machine and the breathing machine, the inspiration valve comprises a valve seat, the valve seat is provided with an air inlet, a main air passage, a safety valve passage and a pressure relief opening communicated with the safety valve passage; the base comprises a base body internally provided with a first cavity and a first pipeline arranged in the first cavity, the first cavity communicates with the pressure relief opening, and the first pipeline is connected with the main air channel; the mounting seat comprises a mounting seat main body internally provided with a second cavity and a second pipeline connected with the first pipeline, and the second cavity is communicated with the first cavity; the cover plate covers the second cavity and is provided with an exhaust port communicated with the second cavity; one end of the air outlet bent pipe penetrates through the cover plate and is connected with the second pipeline, and the orthographic projection of the air outlet bent pipe in the direction of the cover plate covers the exhaust port. According to the air suction valve, the exhaust port can be hidden, the attractiveness of the whole breathing machine is improved, the structural design of a shell of the breathing machine can be simplified, and the production cost is reduced.

The present invention belongs to the technical field of manufacturing high-altitude oxygen masks, and particularly relates to a high-altitude oxygen supply and oxygen-saving respirator. The present invention is composed of an oxygen storage cotton protective cover, oxygen storage cotton, an oxygen storage cotton base, a headband connecting band, a storage cotton inlet pipe, an oxygen mask body, an oxygen inlet pipe, an oxygen coil pipe, an inhalation valve seat, a normally closed negative pressure one-way inhalation valve, a normally closed positive pressure one-way exhalation valve, an exhalation valve seat, and a duckbill one-way drainage valve. When used at high altitudes, the present invention has the oxygen storage function of the oxygen storage cotton, realizes the oxygen accumulation and supply in the respirator with low-flow oxygen supply; has a sealed structure design, and the opening and closing combination of the mask valve group is driven by the human breathing pressure and automatically matches the human breathing rhythm, thereby improving the utilization rate of oxygen and realizing the economical use of oxygen carried at high altitudes; has the functions of reducing the oxygen supply temperature difference and dehumidifying inside the mask, and improves the comfort during long-term use.

The invention relates to respirator technology, in particular to an adaptive auxiliary air supply respirator and a control method thereof. The respirator comprises: a sealing face shield covering the area of the mouth and nose, an internal chamber being formed within the sealing face shield; an exhalation valve connected to the sealing face shield, communicating with the internal chamber, and configured to open unidirectionally during exhalation; an intake chamber located inside the sealing face shield and equipped with an inhalation valve which opens unidirectionally during inhalation; a filter mounted on the sealing face shield and communicating with the intake chamber; and an auxiliary air supply mechanism comprising a fan extending into the intake chamber, a controller for controlling a speed of the fan, and a sensor arranged inside the sealing face shield. The fan draws external air, accelerating during inhalation and decelerating during exhalation, improving user experience.

This application provides a flow control method for an electronically controlled flow meter and an anesthesia machine. The method includes: during the entire inspiratory-expiratory cycle, the electronically controlled flow meter only outputs fresh gas during the inspiratory phase; when outputting fresh gas during the inspiratory phase, the shape of its flow waveform is the same as the flow waveform of the inspiratory valve of the respiratory delivery unit. The advantage of this application is that, compared to traditional methods, the time to reach the target pressure or tidal volume is several inspiratory-expiratory cycles faster.