High-precision bionic respirator detector calibration device

Abstract

The invention provides a respirator detector calibration device. The respirator detector calibration device comprises a first piston device, a second piston device, a pressure sensor, an oxygen concentration mixing module, a control module and a simulated lung, the first piston device comprises one or more sets of piston systems with the same structure, and the oxygen concentration mixing module is connected with the first piston device and the second piston device through pipelines; the first piston device is communicated with the respirator detector to be calibrated through a pipeline; the pressure sensor is connected in series with the second piston device and is communicated with the respirator detector to be calibrated through a pipeline; and the simulated lung is communicated with the respirator detector to be calibrated through a pipeline. The piston type gas standard device is adopted as a gas flow generation device, the oxygen concentration mixing module is communicated with the first piston device and the second piston device, and the device has the advantages of being stable in breathing gas flow, adjustable in pressure, high in measurement efficiency and the like.

Description

Technical Field

[0001] The invention belongs to the field of metrological calibration of medical instruments and equipment, and in particular relates to a ventilator detector calibration device. Background Art

[0002] In modern clinical medicine, ventilators, as an effective means of artificially replacing autonomous ventilation, have been widely used in respiratory failure caused by various reasons, anesthesia respiratory management during major surgery, respiratory support therapy and emergency resuscitation, and they occupy a very important position in the field of modern medicine. However, ventilators are also one of the medical devices that are most prone to problems in clinical practice, with the largest training workload and the greatest difficulty in use. Therefore, strengthening the quality management of ventilators is of great significance to improving their safety and efficiency, improving the success rate of clinical treatment, and reducing clinical risks. As a multi-parameter emergency device, the accuracy of the ventilator's parameters has a significant impact on the clinical treatment effect and even the patient's life safety. Therefore, it is necessary to calibrate the ventilator regularly with a ventilator detector.

[0003] At present, the country does not have traceability standards and calibration specifications for ventilator detectors. Only the two statutory metrology and technical institutions, the China National Institute of Metrology and the China Institute of Testing Technology, are conducting calibration of ventilator detectors based on self-compiled methods, and the methods are not disclosed to the public. At the same time, there is no standard for verification of ventilator detectors during the period, which makes the quality control of ventilator detectors lack support means. What cannot be ignored is that there is no standard device for full-parameter, high-performance calibration of ventilator detectors in China. Therefore, it is of great significance to develop a bionic respiratory measurement parameter generation standard device to simulate the actual biological parameters of the human body, thereby improving the traceability system of ventilator detectors in my country, improving the credibility of clinical ventilator calibration results, and ensuring the life safety of patients. Summary of the invention

[0004] The present invention aims to solve at least one of the technical problems existing in the prior art. To this end, one purpose of the present invention is to provide a ventilator detector calibration device that can meet the requirements of continuous, stable and high-precision generation of static flow of the ventilator detector, while taking into account the value transmission of bionic breathing simulation tidal volume, respiratory rate, airway peak pressure and positive end-expiratory pressure, so as to realize the value traceability of the ventilator.

[0005] In order to achieve the above-mentioned object, the present invention proposes a ventilator detector calibration device, including a first piston device, a second piston device, a pressure sensor, an oxygen concentration mixing module, a control module and a simulated lung.

[0006] According to one embodiment of the present invention, the first piston device comprises one or more piston systems of the same structure. The piston system comprises a cylinder, a piston, a drive device and a grating ruler. The second piston device comprises a cylinder, a piston, a drive device and a grating ruler.

[0007] The oxygen concentration mixing module is connected to the first piston device and the second piston device through pipelines respectively; a first three-way valve is arranged on the pipeline connecting the oxygen concentration mixing module and the first piston device; a second three-way valve is arranged on the pipeline connecting the oxygen concentration mixing module and the second piston device.

[0008] The first piston device is connected to a pipeline of a breathing machine detector to be calibrated through a pipeline.

[0009] The pressure sensor is connected in series with the second piston device and is connected with the ventilator detector to be calibrated through a pipeline.

[0010] The simulated lung is communicated with a ventilator detector to be calibrated through a pipeline.

[0011] A third three-way valve is provided on the pipeline connecting the ventilator detector to be calibrated and the simulated lung.

[0012] The oxygen concentration mixing module includes a plurality of oxygen standard gases of different concentrations.

[0013] The control module is connected to the first piston device, the second piston device, the pressure sensor, the three-way valve, the oxygen concentration mixing module and the respiratory detector to be calibrated, and is used for data collection, processing and control of the first piston device, the second piston device, the pressure sensor, the three-way valve, the oxygen concentration mixing module and the respiratory detector to be calibrated.

[0014] According to one embodiment of the present invention, the cylinder of the piston system of the first piston device includes a lower end cover, and the piston, cylinder body and cylinder lower end cover of the piston system together form a closed working chamber, and the cylinder lower end cover is provided with an air inlet hole and an air outlet hole. The air inlet hole is connected to the air inlet pipeline, and the air inlet valve is provided on the air inlet pipeline; the air outlet hole is connected to the air outlet pipeline, and the air outlet valve is provided on the air outlet pipeline. The air inlet pipeline is connected to the oxygen concentration mixing module, and the air outlet pipeline is connected to the breath detector to be calibrated.

[0015] According to one embodiment of the present invention, the piston system of the first piston device is an active piston type gas flow standard device.

[0016] According to another embodiment of the present invention, the cylinder of the piston system of the first piston device includes an upper end cover and a lower end cover, and the piston, the cylinder body and the upper and lower end covers of the cylinder form two mutually sealed cavities. The upper and lower end covers are both provided with an air inlet hole and an air outlet hole. The air inlet hole is connected to an air inlet pipeline, and an air inlet valve is provided on the air inlet pipeline; the air outlet hole is connected to an air outlet pipeline, and an air outlet valve is provided on the air outlet pipeline. The air inlet pipeline is connected to an oxygen concentration mixing module, and the air outlet pipeline is connected to a breathalyzer to be calibrated. When the piston moves back and forth, both volume chambers can be measured, which can improve the stability and continuity of the gas flow.

[0017] According to one embodiment of the present invention, the first piston device comprises a plurality of piston systems of the same structure, and the air inlet pipelines of the piston systems are connected to form a total air inlet pipeline. The air outlet pipelines of the piston systems are connected to form a total air outlet pipeline. The first piston device is connected to the oxygen concentration mixing module and the ventilator detector to be calibrated through the total air inlet pipeline and the total air outlet pipeline.

[0018] According to one embodiment of the present invention, the first piston device can achieve controllable gas flow rate within the range of 0-180 L / min.

[0019] According to one embodiment of the present invention, the second piston device is an active piston type gas flow standard device.

[0020] According to one embodiment of the present invention, the cylinder capacity of the second piston device is 2000 mL.

[0021] According to one embodiment of the present invention, the oxygen concentration mixing module includes a plurality of oxygen standard gases of different concentrations, and the oxygen standard gases are equipped with corresponding pressure reducing valves, which can realize the oxygen concentration calibration of the ventilator detector within the oxygen concentration range of 21% to 99%.

[0022] When static flow calibration is performed on the respiratory detector to be calibrated, the first three-way valve and the third three-way valve are connected to the atmosphere, and the first piston device is used as a gas flow generating device. The reciprocating motion of the piston generates gas flow, and the static flow calibration is completed through the respiratory detector to be calibrated.

[0023] When calibrating and tracing the dynamic flow and dynamic pressure parameters of the ventilator detector to be calibrated, the third three-way valve is controlled to connect the ventilator detector to be calibrated with the simulated lung to form a closed breathing loop. The second piston device, as a gas flow generating device, can complete the breathing process within the specified exhalation and inhalation time according to the set capacity value through the reciprocating motion of the piston, thereby simulating parameters such as tidal volume, respiratory rate, and peak airway pressure. At the same time, the control module controls the first piston device to output a stable gas pressure to effectively simulate the positive end-expiratory pressure.

[0024] According to one embodiment of the present invention, the oxygen concentration mixing module is composed of four oxygen standard gases with different concentrations and a pressure reducing valve. The oxygen standard gas includes a first oxygen cylinder, a second oxygen cylinder, a third oxygen cylinder and a fourth oxygen cylinder, and the oxygen concentration can be selected from 40%, 60%, 80% and 99%. When calibrating the oxygen concentration of 21%, the control module controls the first three-way valve and the second three-way valve to be connected to the atmosphere; when calibrating the oxygen concentration of 40%, 60%, 80% and 99%, the control module controls the first three-way valve and the second three-way valve to be connected to the oxygen concentration mixing module, and controls the oxygen concentration mixing module through the control module, outputs oxygen concentrations of different concentrations according to the calibration needs, and the oxygen standard gas after decompression is connected to the air inlet of the first piston device and the second piston device, so that the oxygen concentration can be calibrated when calibrating parameters such as dynamic flow, and the normal scene of the ventilator detector can be simulated.

[0025] It can be seen from the above technical solution that the advantages and positive effects of the present invention are:

[0026] (1) The piston-type gas flow standard device is used to simulate the breathing gas flow rate of the human body in different states, solving the problem that the human body's breathing flow rate is difficult to trace. The driving device drives the piston to reciprocate, press out or inhale the air in the cylinder, thereby simulating the exhalation and inhalation process of the lungs, and providing the ventilator detector with a gas flow rate and volume that can be precisely controlled.

[0027] (2) A modular piston group is used in combination with high-precision pressure sensors, simulated lungs and other components to simulate the bionic movement of human respiratory rate, tidal volume, positive end-expiratory pressure and other parameters, to solve the problem of differences in lung movement characteristics among people of different age groups, to adapt to the respiratory characteristics of infants, children and adults, and to evaluate the test results and conduct error analysis.

[0028] (3) The oxygen concentration mixing module is connected to the first piston device and the second piston device through a three-way valve. When calibrating parameters such as dynamic flow of the calibrated ventilator detector, the oxygen concentration can be calibrated to improve the calibration efficiency.

[0029] (4) When calibrating static flow, using a multi-piston system or a double-chamber piston gas flow generator can improve the stability and continuity of the gas flow and provide higher calibration accuracy. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] In order to more clearly illustrate the specific embodiments of the present disclosure or the technical solutions in the prior art, the drawings required for use in the specific embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present disclosure. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0031] Figure 1 It is a structural principle diagram of the static flow generation module and the dynamic breathing simulation module of the present invention;

[0032] Figure 2 is a structural diagram of the first piston device of Example 1;

[0033] Figure 3 is a structural diagram of the first piston device of the second embodiment;

[0034] Figure 4 It is a structural diagram of the second piston device.

[0035] In the figure: 1- oxygen concentration calibration module; 2- first three-way valve; 3- first piston device; 4- second three-way valve; 5- second piston device; 6- pressure sensor; 7- breathing detector to be calibrated; 8- third three-way valve; 9- simulated lung; 10- piston of the first piston device of embodiment 1; 11- cylinder of the first piston device of embodiment 1; 12- air inlet line of the first piston device of embodiment 1; 13- air inlet valve of the first piston device of embodiment 1; 14- air outlet valve of the first piston device of embodiment 1; 15- lower end plate of the cylinder of the first piston device of embodiment 1; 16- first active Plug device air outlet pipeline; 17-first piston device driving device of embodiment one; 20-first piston device air inlet valve of embodiment two; 21-first piston device air outlet valve of embodiment two; 22-first piston device cylinder upper end plate of embodiment two; 23-first piston device piston of embodiment two; 24-first piston device cylinder of embodiment two; 25-first piston device cylinder lower end plate of embodiment two; 30-second piston device piston; 31-second piston device cylinder; 32-second piston device driving device; 33-second piston device grating ruler; 34-second piston device air outlet pipeline. DETAILED DESCRIPTION

[0036] The embodiments of the present invention are described in detail below, examples of which are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and cannot be understood as limiting the present invention.

[0037] In the description of the present invention, it should be understood that the terms "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside" and "outside" etc., indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present invention.

[0038] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features. In the description of the present invention, the meaning of "plurality" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0039] In the present invention, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection, an electrical connection, or can communicate with each other; it can be a direct connection, or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0040] A ventilator detector calibration device provided by the present invention is a metrological standard instrument used to calibrate a respiratory detector. It is a metrological calibration device that integrates standard signal generation, signal monitoring, and data comparison. It includes a first piston device, a second piston device, a pressure sensor, an oxygen concentration mixing module, a control module, and a simulated lung. It can realize calibration and traceability of the static flow, static pressure, dynamic flow, dynamic parameters, inhaled oxygen concentration, etc. of the ventilator detector.

[0041] like Figure 1As shown, a ventilator detector calibration device provided by an embodiment of the present invention comprises a first piston device (3), a second piston device (5), a pressure sensor (6), an oxygen concentration mixing module (1), a control module and a simulated lung (9). The oxygen concentration mixing module (1) is connected to the air intake pipelines of the first piston device (3) and the second piston device (5) through a first three-way valve (2) and a second three-way valve (4), respectively. The pressure sensor (6) is connected in series with the second piston device (5) and is connected to the ventilator detector (7) to be calibrated through a pipeline. A third three-way valve (8) is installed on the rear end pipeline of the ventilator detector (7) to be calibrated; the simulated lung (9) is connected to the ventilator detector (7) to be calibrated through the third three-way valve (8). The embodiment provided by the present invention is different in that the structure of the first piston device (3) is Figure 2 and Figure 3 Two different first piston arrangements are shown.

[0042] refer to Figure 2 The first piston device comprises one or more piston systems with the same structure. The piston system comprises a cylinder body (11), a piston (10), a lower end plate (15), a driving device (17) and a grating ruler. The piston (10), the cylinder body (11) and the cylinder lower end plate (15) together form a closed working chamber. An air inlet pipeline (12) and an air outlet pipeline (16) are provided on the lower end cover of the cylinder. An air inlet valve (13) is provided on the air inlet pipeline (12), and an air outlet valve (14) is provided on the air outlet pipeline (16). When performing static flow calibration, the driving device (17) drives the piston (10) to reciprocate to provide a standard gas flow. When the first piston device is a piston system, the cylinder volume thereof needs to be greater than or equal to 100L. When the first piston device is two or more piston systems with the same structure, the piston system can adopt a multi-cylinder simultaneous operation mode and a multi-cylinder alternating operation mode. The multi-cylinder simultaneous operation mode is that multiple piston systems operate simultaneously to jointly produce a standard flow of gas. The multi-cylinder alternating operation mode is to divide the piston system into two groups of equal number; when working, the two groups of piston systems operate alternately to continuously produce a standard flow of gas, so as to achieve a small cylinder volume to continuously produce a stable large gas flow, reducing the difficulty of cylinder processing.

[0043] In one embodiment of the present invention, the piston system in the first piston device is an active piston type gas flow standard device.

[0044] The second piston device (5) comprises a cylinder (31), a piston (30), a driving device (32) and a grating ruler (33). The driving device (32) of the second piston device is connected to the piston (30) to drive the piston (30) to perform reciprocating motion in the cylinder (31) to simulate the breathing process; the air outlet (34) of the cylinder (31) is connected to the inlet of the ventilator tester to be calibrated through a pipeline; the grating ruler (33) is arranged on the driving device (32) to detect the displacement of the piston; the air outlet of the ventilator tester to be calibrated (5) is connected to the pipeline of the simulated lung (9) through a third three-way valve (8). A pressure sensor (6) is also provided on the pipeline connecting the air outlet (34) of the cylinder and the air inlet of the ventilator tester to be calibrated (7).

[0045] In one embodiment of the present invention, the second piston device is an active piston type gas flow standard device.

[0046] During static flow parameter calibration, the control module controls the first three-way valve (2) and the third three-way valve (8) to be connected to the atmosphere, and the first piston device (3) reciprocates to provide a standard gas flow rate. The first piston device can achieve a controllable gas flow rate of 180 L / min, and can trace the flow value to the national standard through basic physical quantities such as length, time and mass.

[0047] When calibrating and tracing the dynamic flow, dynamic pressure parameters and oxygen concentration of the calibrated ventilator detector, the third three-way valve (8) is connected to the simulated lung (9), and the second piston device (5) simulates the breathing process by the reciprocating motion of the piston (30) in the cylinder. The second piston device (5) delivers gas to the calibrated ventilator detector (7), and the gas enters the simulated lung (9) through the calibrated ventilator detector (7).

[0048] When calibrating the tidal volume, the control module controls the second piston device (5) to start according to the tidal volume test point, so that it provides an accurate tidal volume value according to the set value. When calibrating the gas flow rate, the control module samples, reads and calculates the movement time and piston stroke of the second piston device piston. When calibrating the inhalation time, the control module records the time taken by the cylinder to push out the internal gas, and compares it with the ventilation time of the ventilator tester (7) to be calibrated, so as to achieve the purpose of calibration. When calibrating the exhalation time, the control module records the time taken by the simulated lung to exhaust the internal gas, and compares it with the time when no gas passes through the ventilator tester (7) to be calibrated, so as to achieve the purpose of calibration. When calibrating the respiratory ratio, the ratio of the exhalation time to the inhalation time is calculated by the control module. When calibrating the minute ventilation, the volume of the cylinder delivered gas per minute is accumulated and calculated by the control module.

[0049] When calibrating the peak airway pressure, the pressure sensor (6) records the peak value of the pressure change of the cylinder during the entire air delivery process, that is, the peak airway pressure. When calibrating the positive end-expiratory pressure, the first piston device pushes and outputs a stable pressure, which is the positive end-expiratory pressure. The air supply pressure range is: ±6kPa. When calibrating the average airway pressure, that is, the average pressure of each piston air delivery / exhaust movement, the pressure sensor is used to sample multiple times and then calculated by the control module.

[0050] The oxygen concentration mixing module is composed of four oxygen standard gases with different concentrations and a pressure reducing valve. The oxygen standard gases include a first oxygen cylinder, a second oxygen cylinder, a third oxygen cylinder and a fourth oxygen cylinder, and the oxygen concentration can be selected from 40%, 60%, 80% and 99%. When calibrating an oxygen concentration of 21%, the control module controls the first three-way valve (2) and the second three-way valve (4) to be connected to the atmosphere; when calibrating an oxygen concentration of 40%, 60%, 80% and 99%, the control module controls the first three-way valve (2) and the second three-way valve (4) to be connected to the oxygen concentration mixing module, and controls the oxygen concentration mixing module through the control module to output different oxygen concentrations according to calibration requirements, and the oxygen standard gases after decompression are connected to the air inlets of the first piston device (3) and the second piston device (5), and the oxygen concentration values ​​collected by the ventilator detector to be calibrated are uploaded to the control module for comparison, and the error is calculated to calibrate the oxygen concentration of the ventilator detector to be calibrated. By connecting the oxygen concentration mixing module to the air intake lines of the first piston device and the second piston device, it is possible to calibrate the oxygen concentration while calibrating the dynamic flow and dynamic pressure parameters, thereby improving the calibration efficiency.

[0051] The ventilator detector calibration device of this embodiment can calibrate the dynamic flow parameters of the ventilator detector being calibrated, including tidal volume, gas flow rate, inhalation time, exhalation time, respiratory ratio, respiratory frequency and minute ventilation.

[0052] refer to Figure 3 In one embodiment of the present invention, a respirator detector calibration device is provided, wherein the first piston device comprises one or more piston systems of the same structure, wherein the piston system of the first piston device comprises an upper end cover (22), a cylinder body (24), and a cylinder lower end cover (25), wherein the piston (23), the cylinder body (24), the cylinder upper end cover (22), and the cylinder lower end cover (25) form two mutually sealed cavities. An air inlet pipeline and an air outlet pipeline are provided on the lower end cover. An air inlet valve (20) is provided on the air inlet pipeline, and an air outlet valve (21) is provided on the air outlet pipeline. When performing flow calibration, the piston (23) moves back and forth, and both volume chambers can be measured, thereby improving the stability and continuity of the gas flow.

[0053] The present invention calibrates the static flow, dynamic flow, dynamic pressure, respiratory rate and oxygen concentration of the ventilator detector according to JJF1234-2018 "Ventilator Calibration Specification" and the metrological calibration principles, and the calibration parameters can be achieved as follows:

[0054] Flow range (static): (0~180)L / min, maximum allowable error is no more than ±0.5%;

[0055] Tidal volume range (dynamic): (0~2000)mL, maximum allowable error is no more than ±1%;

[0056] Respiratory rate: (5~80) times / min, the maximum allowable error is no more than ±1%;

[0057] Positive end-expiratory pressure range: 0.1~6kPa, the maximum allowable error is no more than ±1% of the reading or ±30Pa;

[0058] Peak airway pressure range: 0.1~6kPa, the maximum allowable error is no more than ±1% of the reading or ±30Pa;

[0059] Temperature: 0~50℃, maximum allowable error ±0.1℃;

[0060] Oxygen concentration range: 21%~100%, the maximum allowable error is no more than ±0.65% (volume fraction).

[0061] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "illustrative embodiments", "examples", "specific examples", or "some examples" means that the specific features, structures, materials, or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described may be combined in any one or more embodiments or examples in a suitable manner.

[0062] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the claims and their equivalents.

Claims

1. A ventilator detector calibration device, characterized in that: include: A first piston device, a second piston device, a pressure sensor, an oxygen concentration mixing module, a control module, and a simulated lung; The first piston device comprises one or more piston systems with the same structure, and the piston system comprises a cylinder, a piston, a driving device and a grating ruler; the first piston device is connected to the ventilator to be calibrated through a pipeline; The second piston device comprises a cylinder, a piston, a driving device and a grating ruler; The oxygen concentration mixing module is connected to the first piston device and the second piston device through pipelines respectively; a first three-way valve is provided on the pipeline connecting the oxygen concentration mixing module and the first piston device; a second three-way valve is provided on the pipeline connecting the oxygen concentration mixing module and the second piston device; The pressure sensor is connected in series with the second piston device and is connected to the ventilator detector to be calibrated through a pipeline; The simulated lung is connected to the ventilator detector to be calibrated through a pipeline; a third three-way valve is provided on the pipeline connecting the ventilator detector to be calibrated and the simulated lung; The oxygen concentration mixing module includes a plurality of oxygen standard gases of different concentrations; The control module is connected to the first piston device, the second piston device, the pressure sensor, the three-way valve, the oxygen concentration mixing module and the respiratory detector to be calibrated, and is used for data collection, processing and control of the first piston device, the second piston device, the pressure sensor, the three-way valve, the oxygen concentration mixing module and the respiratory detector to be calibrated.

2. The ventilator detector calibration device according to claim 1, characterized in that: The first piston device and the second piston device are active piston type gas flow standard devices.

3. The ventilator detector calibration device according to claim 1, characterized in that: The piston system cylinder comprises an upper end cover and a lower end cover, and the piston, the cylinder body and the upper and lower end covers of the cylinder form two mutually sealed cavities.

4. The ventilator detector calibration device according to claim 1, characterized in that: The first piston device can provide a gas flow rate of 0-180 L / min.

5. The ventilator detector calibration device according to claim 1, characterized in that: The cylinder capacity of the second piston device is 2000 mL.

6. The ventilator detector calibration device according to claims 1 to 5, characterized in that: The oxygen concentration of the oxygen standard gas is 21%, 40%, 60%, 80% and 99%.

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