280 results about "Positive pressure" patented technology

Embodiments of negative pressure wound therapy systems and methods for operating the systems are disclosed. In some embodiments, a system includes a pump assembly, canister, and a wound dressing configured to be positioned over a wound. The pump assembly, canister, and the wound dressing can be fluidically connected to facilitate delivery of negative pressure to a wound. The system can additionally include a valve configured to control the introduction of positive pressure to the wound.

The invention discloses an automatic positive pressure tube sealing device and a tube washing device in the technical field of medical auxiliary instruments. The automatic positive pressure pipe sealing device comprises a liquid supply mechanism, the liquid supply mechanism comprises a liquid storage pipe and a pushing assembly, and the pushing assembly is arranged in a containing cavity of the liquid storage pipe. The pushing assembly comprises a piston and a pushing rod, the piston is arranged in the containing cavity, an elastic piece is arranged between the pushing rod and the piston, mechanical energy generated when the pushing rod moves is converted into stable elastic potential energy, the elastic piece is used for slowly releasing the elastic potential energy, and the piston can apply pressure to liquid in the liquid storage pipe for a long time; the liquid in the liquid storage tube is in a positive pressure state for a long time and can be in a positive pressure state relative to the blood pressure of a human body for a long time, and blood is prevented from flowing back to the venous catheter. After the push rod moves towards the piston by a certain distance, the push rod and the liquid storage pipe can be kept relatively fixed, the elastic piece can release elastic potential energy in the direction close to the piston, the elastic potential energy of the elastic piece completely acts on the piston, and automatic pipe sealing operation is achieved.

An interface for positive pressure respiratory therapy includes a mask assembly having a mask seal and a mask shell. The mask assembly is positioned lower than and exposes a bridge of the user's nose. The mask seal includes first and second portions on respective first and second sides of a nasal region that contact opposing sides of the user's nose. The first and second portions each include supports that help maintain a shape of the mask seal. A pair of covers can be supported relative to the mask assembly and adjacent a respective one of the first and second portions of the mask seal. The covers limit expansion of the first and second portions of the mask seal in response to pressurized air within the mask seal. The supports of the first and second portions can transfer load from the mask seal to the covers.

The invention relates to a positive pressure type air purification system and method for a limited space, by constructing a relatively closed space and adopting an efficient multi-stage filtering technology, the system can quickly remove particulate matters, bacteria, viruses and harmful gases in air, and the air quality in the limited space is remarkably improved. The positive pressure control method ensures that external polluted air cannot enter, and the cleanliness of the working environment is further guaranteed. The intelligent control system achieves remote monitoring and automatic adjustment through the Internet of Things technology, the response speed and operation convenience of the system are improved, real-time data analysis and trend reports are provided, and a user is helped to better manage and maintain the system. In addition, proper working conditions are ensured through the temperature and humidity adjusting function, and therefore a healthy, safe and efficient working environment is provided for workers. According to the invention, the working conditions with strict requirements on the air cleanliness are met, and the user experience and the reliability of the system are greatly improved.

The invention discloses a constant-frequency positive-pressure superposition high-frequency oscillation supporting device and method applied to a breathing machine, and belongs to the technical field of medical breathing machines, and the constant-frequency positive-pressure superposition high-frequency oscillation supporting device comprises a monitoring module for monitoring physical state data of a patient; the evaluation module is used for evaluating whether auxiliary sputum excretion operation needs to be carried out or not according to the physical state data; the equipment control module is used for determining ventilation parameters of the ventilation equipment and foam driving parameters of the foam driving equipment according to the body state data; the ventilation equipment is used for providing ventilation airflow and ventilation pressure for the patient according to the ventilation parameters; the lung sputum monitoring module is used for monitoring the lung sputum discharge state of the patient and adjusting foam driving parameters according to the lung sputum discharge state. According to the breathing machine, the combination of ventilation and sputum excretion functions of the breathing machine is realized through a method of combining a foam-driven sputum excretion technology with a ventilation technology.

The utility model relates to the technical field of equipment testing, in particular to a control circuit of breathing machine testing equipment and the breathing machine testing equipment. The main control board controls the breathing machine test equipment to generate positive pressure or negative pressure by controlling the positive and negative pressure control circuit; by controlling the air pressure flow control circuit to control the flow and pressure of air generated by the respirator test equipment, the control circuit of the respirator test equipment can control the respirator test equipment to generate accurate negative pressure or positive pressure to a simulated lung through the positive and negative pressure control circuit and the air pressure flow control circuit; the simulated lung can simulate the lung pressure of a patient, control requirements of various pressures and flows during testing of the breathing machine to be tested are met, and whether various functional parameters, performance parameters and alarm indexes output by the breathing machine to be tested meet requirements or not is tested. Manual participation is not needed, the testing efficiency is greatly improved while the testing cost is reduced, and automatic testing of the breathing machine is achieved.

The invention relates to a sucking massage structure and a massager, and belongs to the technical field of massage equipment. The sucking massage structure comprises a first massage opening, a second massage opening and a pneumatic control assembly, and the first massage opening and the second massage opening are used for being attached to the skin of a massage part; the pneumatic control assembly is respectively communicated with the first massage opening and the second massage opening; the air control assembly alternately blows and sucks air to the skin of the massage part through the first massage opening and the second massage opening so as to apply positive pressure and negative pressure. The pneumatic control assembly is configured to apply opposite air pressure to the skin of the massage part through the second massage opening when positive pressure or negative pressure is applied to the skin of the massage part through the first massage opening; the first massage opening and the second massage opening share at least part of the side wall. According to the sucking massage structure provided by the embodiment of the invention, the massage effect can be improved, and better use experience can be provided for a user.

The invention provides a wearable mask (10) for monitoring a blood pressure value and providing a flow of gas at a positive pressure to the patient. The mask includes a first sensor (24a, 24b), configured to measure a time-dependent optical waveform from a first region underneath a first portion of the wearable mask, with the time dependent optical waveform including a first pulse. A second sensor (30a, 30b, 32a, 32b) measures a time-dependent impedance waveform from a second region proximal to the mask, with the time-dependent impedance waveform including a second pulse. A microprocessor (14) attaches to the wearable mask and is configured to: 1) receive digital representations of both the first and second pulses; 2) process the digital representations to determine a time difference between the first and second pulses, or a parameter calculated therefrom; and 3) process the time difference between the first and second pulses, or the parameter calculated therefrom, to determine the blood pressure value.

A method of manufacturing a patient interface for sealed delivery of a flow of air at a continuously positive pressure with respect to ambient air pressure to an entrance to the patient's airways includes collecting anthropometric data of a patient's face. Anticipated considerations are identified from the collected anthropometric data during use of the patient interface. The collected anthropometric data is processed to provide a transformed data set based on the anticipated considerations, the transformed data set corresponding to at least one customised patient interface component. At least one patient interface component is modelled based on the transformed data set.

An interface for use in providing positive pressure respiratory therapy, the interface comprising:a mask assembly comprising a mask seal and a mask shell, the mask assembly configured to be fully positioned lower than a bridge of a nose of a face of a user and to provide an exposed bridge of the nose of the user, the mask seal being connected to the mask shell, a nasal region comprising at least one nasal opening, the mask seal comprising a first paddle on a first side of the nasal region and a second paddle on a second side of the nasal region, the first paddle configured to contact one side of the nose of the user and the second paddle configured to contact the other side of the nose of the user;

A patient interface device to deliver continuous positive pressure gas from a ventilator to a user's nasal airway, which includes a front chamber section, a sealing structure, a ventilation component, and a positioning stabilizer. The front chamber section is bent towards one side of the user's face to form a main chamber and has at least one opening to install the ventilation component. The sealing structure has two shaped single-layer wall protrusions and communicates with the main chamber of the front chamber section. The ventilation component includes a noise reduction material, a ventilation component body, and a port cover. The positioning stabilizer is configured to be set on both ends of the front chamber section to provide a connection between components to secure the patient interface device. When in use, the exhaled waste gas is discharged into an external environment through the ventilation component.

The present invention relates to the field of medical device technology, and in particular to a dental chair water-gas separation system, a dental chair, and a method for using the dental chair water-gas separation system. The dental chair water-gas separation system comprises: a tank body has a liquid storage cavity inside, and the outer wall of the tank body has a water-gas inlet, a liquid discharge port, and an exhaust port connected to the liquid storage cavity; a pressure mechanism is used to output a negative pressure source and a positive pressure source, and the negative pressure source is connected to the exhaust port, so that a negative pressure is formed in the liquid storage cavity; the positive pressure source is connected to the liquid storage cavity, so that a positive pressure is formed in the liquid storage cavity, so as to provide a driving force for the liquid in the liquid storage cavity to flow to the liquid discharge port. The dental chair water-gas separation system of the present invention is connected to a positive pressure source during liquid discharge, so that the liquid is squeezed to accelerate the discharge of the tank body, which effectively shortens the liquid discharge time compared to the traditional method of relying on gravity to discharge liquid, thereby shortening the time of disconnection of the negative pressure source, making the doctor's operation smoother, improving the doctor's experience, and avoiding the problem of increased fluid accumulation in the patient's mouth due to long liquid discharge time, thereby alleviating the patient's discomfort.

The invention provides a one-way bioreactor sampling connecting device and application thereof, and relates to the technical field of bioreactor culture, the one-way bioreactor sampling connecting device comprises a sealing cover, a sampling pipe penetrating through the sealing cover, a sampling pipeline communicated with the sealing cover, and a pressure adjusting pipeline; a sample in the bioreactor is guided to a sample collecting device through a sampling pipeline, the sampling pipeline can enable liquid in the bioreactor to flow into the sample collecting device through a peristaltic pump, the sampling pipeline is closed, and the liquid cannot flow back into the bioreactor; the pressure adjusting pipeline can be used for carrying out pressure maintaining air tightness detection on the sampling bottle, and also can be used for sampling through the liquid outlet end of the sampling pipe after compressed air is introduced for pressurization to enable the pressure in the bottle to be positive pressure. The technical problems that in the prior art, repeated negative pressure pumping sampling is needed, flow cutoff is likely to happen, bubbles are generated, the biochemical characteristics of samples are affected, backflow is likely to be caused, and operation is complex and pollution is caused are solved.

The invention belongs to the technical field of medical instruments, and discloses a synchronous oxygen supply breathing device which comprises a vertical mounting plate, a telescopic frame is movably mounted on one side of the vertical mounting plate, a pressing pad is mounted at the end of the telescopic frame, and a ventilation seat and an oxygen supply pipeline are sequentially mounted on the side face of the vertical mounting plate from top to bottom. An electromagnetic valve is installed on the oxygen catheter, an oxygen mask is installed at the end of the oxygen catheter, the ventilation seat and the oxygen supply pipeline are both communicated with a folding air bag, a rotating arm is installed on the side face of the vertical installation plate, one end of the folding air bag is installed on the vertical installation plate, and the other end of the folding air bag is installed on the rotating arm. The electromagnetic valve is opened at set intervals, and the transmission piece drives the folding air bag to contract and positive pressure is formed in the folding air bag only within the time when the pressing pad is away from the chest of the patient along with the telescopic frame, so that gas stored in the folding air bag is input into the oxygen mask through the oxygen catheter, and ventilation is completed.

Disclosed herein is a pulsating aspiration system including a catheter and a pump system. The catheter includes an outer wall, a proximal portion, a distal portion, and an inner wall dividing the proximal portion into a central main lumen and an auxiliary lumen. The pump system is in fluid communication with the catheter and independently controls negative and positive fluid pressures within the central main and auxiliary lumens to generate a pulsating aspiration waveform at the distal end of the catheter that is variable between a maximum aspiration pressure and a maximum positive pressure. The maximum aspiration pressure can be generated at the distal end of the catheter when the resulting pressure is solely negative fluid pressure, and the maximum positive pressure can be generated at the distal end of the catheter when the positive fluid pressure balances the negative fluid pressure.

The invention relates to an orthopedic device comprising a main part with a first surface which is provided with at least one adhesive region. At least one recess is provided in the main part, said at least one recess being at least partly formed behind the adhesive region and being provided with a pressure and / or suction connection. The first surface is designed to be at least partly suctioned into the recess when negative pressure is applied in the at least one recess and / or pushed out when positive pressure is applied.

Fluid reservoir (113; 213; 313) for an aspiration line (107) of a medical system, wherein the aspiration line (107) serves to aspirate a fluid from a surgical site on a living being by means of a fluid pump of the medical system in a suction direction, comprising: - a shell (214; 314) enclosing a chamber (219; 319) designed to hold a fluid; - a separating element (215; 315) that divides the chamber (219; 319) into a first sub-chamber (219a; 319a) and a second sub-chamber (219b; 319b); - a first fluid connection (220; 320) designed to fluidically connect the first subchamber (219a; 319a) to an outer surface of the shell (214; 314), and designed to be connected to a first part (107a) of the aspiration line (107) to be connected to the fluid pump; - a second fluid port (222; 322) designed to fluidically connect the second subchamber (219b; 319b) to the outer surface of the shell (214; 314), and designed to be connected to a second part (107b) of the aspiration line (107) to be directed towards the surgical site; and - a backflow preventer that the separating element (215; 315) has to fluidically connect the first subchamber (219a; 319a) with the second subchamber (219b; 319b), wherein the backflow preventer is designed to prevent a flow of fluid from the first subchamber (219a; 319a) into the second subchamber (219b, 319b) in the opposite direction to the suction direction, and wherein the separating element is a flexible separating element (215; 315), and the flexible separating element (215; 315) is designed in such a way as to achieve a pumping effect of the fluid reservoir (113; 213; 313) in the second subchamber (219b; 319b) when the flexible separating element (215; 315) is deformed by a certain positive pressure difference between the first subchamber (219a; 319a) and the second subchamber (219b; 319b), which enables the conveyance of a certain fluid delivery volume, characterized by the fact that the specific fluid flow volume is chosen depending on the type of operation performed on a living being.

A patient interface for delivering a flow of air at positive pressure relative to ambient air pressure to an entrance to the patient's airways to ameliorate sleep disordered breathing comprises a seal-forming structure to form a seal with a region of the patient's face surrounding an entrance to the patient's airways, a positioning and stabilising structure to provide a force to hold the seal-forming structure in a therapeutically effective position on the patient's head, and a connector assembly adapted to connect to an air circuit. The connector assembly comprises a loop member removably and releasably secured in an aperture of an attachment region of the patient interface and an elbow assembly connected to the air circuit and repeatedly connectable to and detachable from the loop member. The elbow assembly comprises an elbow member and a clip member. The clip member comprises a structure separate and distinct from the elbow member and is connected to the elbow member and releasably connects the elbow assembly to the loop member, the elbow member forming a seal with the loop member when the elbow assembly and loop member are connected to each other.

The invention discloses a closed positive pressure connector, and relates to the technical field of medical machinery. Comprising a shell, an input port and an output port are formed in the upper end and the lower end of the shell respectively, a piston is arranged in the shell, the periphery of the top of the piston is attached to the inner wall of the shell in a sealed mode to form a positive pressure cavity, a push plate is connected to the bottom of the piston through a bearing, and a first elastic piece is installed between the bottom of the push plate and a bottom solid area of the shell; a pushing mechanism is mounted on one side in the piston and comprises a first mounting groove, a push rod is connected into the first mounting groove through a second elastic piece, a sealing push plate is fixedly connected to the top of the push rod and sleeves the periphery of the connecting column, and a connecting groove is formed in the bottom of the push rod; and a pull-back assembly is mounted in the connecting groove, so that constant pressure is always kept in the positive pressure cavity, and blood backflow and thrombus formation are effectively avoided.

A pumping system comprising: a pneumatically driven diaphragm pump comprising: a rigid chamber wall; a rigid limit structure; a flexible diaphragm attached to the rigid chamber wall and interposed between the rigid chamber wall and the rigid limit structure, such that the flexible diaphragm and rigid chamber wall together define a pumping chamber and the flexible diaphragm and the rigid limit structure together define an actuation chamber; an inlet in the rigid chamber wall for allowing liquid to enter the pumping chamber; and an outlet in the rigid chamber wall for allowing liquid to exit the pumping chamber; an actuation system that alternately provides either a positive or a negative pressure to the actuation chamber; wherein the actuation system includes: a first reservoir held at a positive pressure; a second reservoir held at a negative pressure; a valving mechanism selectively connecting the actuation chamber to one of the first and second reservoirs to control a pressure in the actuation chamber; and an actuation chamber pressure transducer for measuring a pressure of the actuation chamber; and a controller that receives pressure information from the actuation chamber pressure transducer and in a first time period controls the valving mechanism to complete at least one full stroke of the flexible diaphragm by moving the flexible diaphragm between a position touching the rigid limit structure and a position touching the rigid chamber wall, the controller being configured to record a full stroke value for a stroke parameter corresponding to each at least one full stroke, and in a subsequent time period to control the valving mechanism to complete partial strokes of the flexible diaphragm by controlling the stroke parameter to be a fraction of the full stroke value.

The utility model belongs to the technical field of wafer cleaning, and particularly relates to a liquid supply device, which comprises a liquid medicine intermediate container, at least one air pipe and at least one liquid inlet pipe are communicated from the upper part to the inner cavity of the liquid medicine intermediate container, and a liquid discharge pipe is arranged from the inner cavity to the lower part of the liquid medicine intermediate container; the valve assembly comprises an air valve arranged at the air pipe; when the air valve is opened, air is introduced into the inner cavity through the air pipe, so that the cavity is in positive pressure, and liquid medicine is discharged through the liquid discharging pipe; or air is pumped out of the inner cavity through the air pipe to enable the cavity to be in negative pressure, and liquid medicine is sucked through the liquid inlet pipe; when liquid is supplied, air in the inner cavity can be exhausted through the air pipe, low pressure is formed in the inner cavity, the liquid inlet pipe is opened, and the low pressure of the inner cavity continuously and quickly sucks liquid medicine; after the liquid medicine is in place, the liquid inlet pipe and the air pipe are closed, the air pipe pumps air into the inner cavity to form high pressure in the liquid medicine intermediate container, the liquid discharge pipe is opened, the liquid medicine is discharged through the high pressure of the inner cavity, power is provided for the liquid medicine, an existing special pump machine is replaced, the manufacturing cost of the device is reduced, and the working efficiency is improved.

Provided herein are medical devices, assemblies, and methods for circulating materials within a medical device. The adapter includes a shaft, a cannula, a female orifice lock, a male conical surface, and threads, all designed for reversible engagement and material circulation. The assembly incorporates the adapter and is designed for use with a variety of medical devices, including bone screws. The method includes engaging a medical device having a pressurizing device and a scaffold with the adapter and circulating material in the medical device via negative or positive pressure. These innovations provide a versatile approach to circulating materials within a medical device, which can be beneficial in a variety of medical procedures and therapies and can increase the efficiency and effectiveness of material circulation.

Provided herein is a device comprising a cuirass, which includes a shell, at least one sensor, a pressure creation means for providing at least one of a negative pressure or a positive pressure within the shell, and a controller operably connected to the pressure creation means, wherein the controller is adapted to receive an input signal from the at least one sensor and adapted to provide an output signal to the pressure creation means, and wherein the pressure creation means is adapted to provide a greater or lesser amount of pressure within the shell in response to the output signal. Also provided are methods of use.

This application discloses a pressure supply device, relating to the technical field of organoids. The pressure supply device includes: a housing having an installation cavity; a positive pressure supply assembly disposed within the installation cavity, including: a first pipe, a first pump, and a first proportional valve, the first pipe having a first gas inlet and a first gas outlet, the first gas inlet being for communication with a gas source, the first gas outlet being for communication with a positive pressure interface of a culture box, the first pump and the first proportional valve being both installed in the first pipe, and the first proportional valve being located between the first pump and the first gas outlet; and a negative pressure supply assembly disposed within the installation cavity, including: a second pipe, a second pump, and a second proportional valve, the second pipe having a second gas inlet and a second gas outlet, the second pump and the second proportional valve being both installed in the second pipe, the second proportional valve being located between the second pump and the second gas inlet, and the second gas inlet being for communication with a negative pressure interface of a culture box.

An interface for positive pressure respiratory therapy includes a mask assembly having a mask seal and a mask shell. The mask assembly is positioned lower than and exposes a bridge of the user's nose. The mask seal includes first and second portions on respective first and second sides of a nasal region that contact opposing sides of the user's nose. The first and second portions each include supports that help maintain a shape of the mask seal. A pair of covers can be supported relative to the mask assembly and adjacent a respective one of the first and second portions of the mask seal. The covers limit expansion of the first and second portions of the mask seal in response to pressurized air within the mask seal. The supports of the first and second portions can transfer load from the mask seal to the covers.

The invention relates to the technical field of medicine spraying equipment, in particular to medicine spraying equipment for clinical nursing of a patient. The device comprises a medicine storage tank, a suction assembly is arranged in the medicine storage tank, the end, away from the medicine storage tank, of the suction assembly is connected with a driving assembly, and the driving assembly is connected with a spraying assembly and a liquid discharging assembly; when the piston is located in the hollow rod, negative pressure is generated on the side close to the main push rod, positive pressure is generated on the side away from the main push rod, increased air pressure is diffused into the medicine storage tank through the fixed suction pipe and the movable suction pipe, meanwhile, the stirring blades are driven by diffusion airflow and rotate at the layering position of the suspension type medicine, and therefore the medicine at the L-shaped outlet is mixed. The second branch pipe connected with the negative pressure side of the hollow rod is always in an open state, so that air pressure on the negative pressure side of the hollow rod is diffused to the suction nozzle, the suction nozzle continuously sucks saliva secreted by a patient due to invasion of foreign matters into the mouth, and the saliva flows into the collecting bottle along the direction of the suction nozzle, the second branch pipe, the third branch pipe and the collecting bottle.

The present invention discloses an anti-pulsation balloon fatigue testing device and its testing method, which includes a testing box body, a visualization cylinder body and a pneumatic pressure compensation device. The balloon is connected to a positive pressure regulating valve and a negative pressure regulating valve respectively through air pipes, and solenoid valves are used to control the air flow. When positive pressure is injected into the balloon, the solenoid valve controlling the positive pressure is opened, and the solenoid valve controlling the negative pressure is closed. Conversely, the solenoid valve controlling the positive pressure is closed, and the solenoid valve controlling the negative pressure is opened, so as to achieve the switching state of positive and negative pressures inside the balloon. The testing box body not only provides positive and negative pressures inside the balloon, but also can record the number of cycles. The present invention simulates the environment of blood vessels in the human body through the visualization cylinder body, and realizes the diastolic and systolic functions of the anti-pulsation balloon through the alternating cycle test of positive and negative pressures, so as to realize the fatigue test of the anti-pulsation balloon, and the test is more efficient.

This utility model discloses a positive and negative pressure switching fresh air system, comprising: an intake fan connected to an air distribution box via pipes, the air distribution box connected to the intake valves of each room via pipes and silencers; a return fan connected to a collection box via pipes, the collection box connected to the return air valves of each room via pipes; when the intake fan is turned on and all the intake and return air valves of all rooms are fully open, all rooms are in a positive pressure state; when the return fan is turned on and all the intake and return air valves of all rooms are fully open, the return air volume is greater than the intake air volume, and all rooms are in a negative pressure state; when both the intake and return air fans are fully open, if room 1 opens its intake valve and closes its return air valve, room 1 is in a positive pressure state; if room 2 opens its return air valve and closes its intake valve, room 2 is in a negative pressure state; positive pressure rooms prevent virus intrusion, and negative pressure rooms prevent virus spillover; infected individuals live in negative pressure rooms, and uninfected individuals live in positive pressure rooms, which can prevent cross-infection among family members and is very suitable for the current virus transmission situation.

A mechanical ventilation system comprises a plurality of ventilation therapy sub-systems. Each of the ventilation therapy sub-systems is adapted to assist a respiratory function of the patient. The system also comprises a detector of the respiratory drive of the patient, an operator interface receiving one or more control parameters, and a main controller. The main controller assigns a therapeutic contribution to each of the ventilation therapy sub-systems based on the respiratory drive of the patient and on the control parameters. The controller modulates the respiratory drive of a patient by controlling each of the plurality of the ventilation therapy sub-systems according to its assigned therapeutic contribution. Distinct ventilation therapy sub-systems may apply negative pressure on the abdomen of the patient, deliver a non-pressurizing inspiratory flow to the patient, or induce a positive pressure in the airways of the patient.

The invention relates to the technical field of medical instruments, in particular to a tuberculosis ward atomization respirator with a negative pressure collection function, comprising: a mask assembly, the mask assembly comprises a breathing mask and a sealing strip, and the breathing mask is internally provided with an air pressure sensor for identifying air pressure change; the atomization assembly is connected with the mask assembly and used for intermittently conveying atomized medicine into the breathing mask. During expiration, the airflow adjusting assembly does not hinder the gas flow rate of the gas feeding pipe, the gas flow rate is increased, and a low-pressure area is formed at the position of the pressure-adjustable one-way valve assembly, so that the pressure-adjustable one-way valve assembly does not hinder communication of the exhaust pipe and the negative-pressure pipe; the exhaust gas in the breathing mask is exhausted outwards through the exhaust pipe and the negative pressure pipe, the airflow adjusting assembly reduces the gas flow rate of the gas feeding pipe at the end of expiration, negative pressure collection is not conducted on the gas in the breathing mask at the end of expiration any more, namely positive pressure is provided at the end of expiration, and early closure of pulmonary alveoli is avoided.