High-precision bionic respirator detector calibration device

Abstract

The utility model 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 used as a gas flow generating 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 measuring efficiency and the like.

Description

Technical Field

[0001] The utility model belongs to the field of metrological calibration of medical instrument equipment, and particularly relates to a calibration device for a ventilator detector. Background Art

[0002] In modern clinical medicine, as an effective means to realize artificial replacement of the autonomous ventilation function, the ventilator has been widely used in respiratory failure caused by various reasons, anesthesia respiratory management during major surgeries, respiratory support treatment and first aid resuscitation, and occupies a very important position in the field of modern medicine. However, the ventilator is also one of the medical devices that are most prone to problems clinically, with the largest training workload and the greatest difficulty in use. Therefore, strengthening the quality management of the ventilator is of great significance for improving its safety and use efficiency, increasing the success rate of clinical treatment, and reducing clinical risks. As an emergency device integrating multiple parameters, the accuracy of the parameters of the ventilator has a significant impact on the clinical treatment effect and even the life safety of patients. Therefore, it is necessary to regularly calibrate the ventilator with a ventilator detector.

[0003] At present, there are no relevant traceability standards and calibration specifications for ventilator detectors in the country. Only the two legal metrological technical institutions, the National Institute of Metrology and the National Institute of Testing Technology, are carrying out the calibration of ventilator detectors according to their self-developed methods and the methods are not publicly available. At the same time, the standard for the intermediate verification of ventilator detectors is also blank, making the quality control of ventilator detectors lack support means. In particular, it cannot be ignored that there is no standard device for calibrating ventilator detectors with full parameters and high performance in China. Therefore, it is of great significance to develop a bionic respiratory metrological parameter generating standard device to simulate the actual biological parameters of the human body, so as to improve the value traceability system of ventilator detectors in China, increase the credibility of the calibration results of clinical ventilators, and ensure the life safety of patients. Summary of the Invention

[0004] The utility model aims to solve at least one of the technical problems existing in the prior art. For this purpose, an object of the utility model is to provide a calibration device for a ventilator detector, which can generate a continuous, stable and high-precision static flow of the ventilator detector, and at the same time can take into account the value transfer of bionic respiration to simulate tidal volume, respiratory rate, peak airway pressure and positive end-expiratory pressure, so as to realize the value traceability of the ventilator.

[0005] To achieve the above object, the utility model provides a calibration device for a ventilator detector, 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 an embodiment of the present utility model, the first piston device includes one set or multiple sets of piston systems with the same structure. The piston system includes a cylinder, a piston, a driving device, and a grating scale. The second piston device includes a cylinder, a piston, a driving device, and a grating scale.

[0007] The oxygen concentration mixing module is respectively connected to the first piston device and the second piston device through pipelines; 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 the pipeline of the ventilator detector to be calibrated through a pipeline.

[0009] 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.

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

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

[0012] The oxygen concentration mixing module includes multiple oxygen standard gases with 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 ventilator detector to be calibrated, and is used for data acquisition, 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 ventilator detector to be calibrated.

[0014] According to an embodiment of the present utility model, the cylinder of the piston system of the first piston device includes a lower end cover. The piston, the cylinder block of the piston system, and the lower end cover of the cylinder together form a sealed working chamber. An air inlet hole and an air outlet hole are arranged on the lower end cover of the cylinder. The air inlet hole is connected to an air inlet pipeline, and an air inlet valve is arranged on the air inlet pipeline; the air outlet hole is connected to an air outlet pipeline, and an air outlet valve is arranged 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 ventilator detector to be calibrated.

[0015] According to an embodiment of the present utility model, 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 utility model, the cylinder of the piston system of the first piston device includes an upper end cover and a lower end cover. The piston, the cylinder block, and the upper and lower end covers of the cylinder form two mutually sealed cavities. Both the upper and lower end covers are provided with air inlet holes and air outlet holes. The air inlet holes are connected to an intake pipeline, and an intake valve is provided on the intake pipeline; the air outlet holes are connected to an exhaust pipeline, and an exhaust valve is provided on the exhaust pipeline. The intake pipeline is connected to an oxygen concentration mixing module, and the exhaust pipeline is connected to a respiratory detector to be calibrated. When the piston moves back and forth, both volume cavities can be measured, which can improve the stability and continuity of gas flow.

[0017] According to an embodiment of the present utility model, the first piston device includes multiple sets of piston systems with the same structure. The intake pipelines of the piston systems are connected to form a total intake pipeline. The exhaust pipelines of the piston systems are connected to form a total exhaust pipeline. The first piston device is connected to the oxygen concentration mixing module and the respiratory detector to be calibrated through the total intake pipeline and the total exhaust pipeline respectively.

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

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

[0020] According to an embodiment of the present utility model, the cylinder volume of the second piston device is 2000 mL.

[0021] According to an embodiment of the present utility model, the oxygen concentration mixing module includes multiple oxygen standard gases with different concentrations. The oxygen standard gases are equipped with corresponding pressure reducing valves, and can achieve oxygen concentration calibration of the respiratory detector within the range of 21% - 99% oxygen concentration.

[0022] When performing static flow calibration on the respiratory detector to be calibrated, the first three-way valve and the third three-way valve are connected to the atmosphere. The first piston device serves as a gas flow generating device. The reciprocating movement of the piston generates gas flow, and 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 respiratory detector to be calibrated, the third three-way valve is controlled to connect the respiratory detector to be calibrated to the simulated lung, forming a respiratory closed loop. The second piston device serves as a gas flow generating device. Through the reciprocating movement of the piston, the breathing process can be completed within the specified exhalation and inhalation times according to the set volume value, realizing the simulation of 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 positive end-expiratory pressure.

[0024] According to an embodiment of the present utility model, 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 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 to output oxygen concentrations with different concentrations according to the calibration requirements. After the reduced-pressure oxygen standard gas is connected to the inlets of the first piston device and the second piston device, it is possible to calibrate the oxygen concentration during the calibration of parameters such as dynamic flow rate, and simulate the normal scenario of the ventilator detector.

[0025] As can be seen from the above technical solutions, the advantages and positive effects of the present utility model are as follows:

[0026] (1) Use the piston-type gas flow standard device to simulate the breathing gas flow rates of different human states, and solve the problem that it is difficult to trace the human breathing flow rate. The driving device drives the piston to reciprocate, squeezing out or inhaling the air in the cylinder, thereby simulating the exhalation and inhalation processes of the lungs, and providing a gas with a precisely controllable flow rate and volume for the ventilator detector.

[0027] (2) Adopt a combined piston group combined with high-precision pressure sensors, simulated lungs and other components to simulate the bionic movements of parameters such as human breathing frequency, tidal volume, and positive end-expiratory pressure, solve the problem of differences in lung movement characteristics among different age groups, adapt to the breathing characteristics of infants, children, and adults, and can evaluate the test results and analyze errors.

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

[0029] (4) When calibrating the static flow rate, adopt a multi-piston system or a double-chamber piston-type gas flow generator, which can improve the stability and continuity of the gas flow rate and has higher calibration accuracy. Description of the Drawings

[0030] To more clearly illustrate the specific embodiments of the present disclosure or the technical solutions in the prior art, the following will briefly introduce the drawings required for the description of the specific embodiments or the prior art. Obviously, the drawings in the following description are some embodiments of the present disclosure. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0031] Figure 1 is the structural schematic diagram of the static flow generation module and the dynamic breathing simulation module of the present utility model;

[0032] Figure 2 is the structural diagram of the first piston device in the first embodiment;

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

[0034] Figure 4 is the 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 in the first embodiment; 11 - cylinder block of the first piston device in the first embodiment; 12 - intake pipeline of the first piston device in the first embodiment; 13 - intake valve of the first piston device in the first embodiment; 14 - exhaust valve of the first piston device in the first embodiment; 15 - lower end plate of the cylinder block of the first piston device in the first embodiment; 16 - exhaust pipeline of the first piston device in the first embodiment; 17 - driving device of the first piston device in the first embodiment; 20 - intake valve of the first piston device in the second embodiment; 21 - exhaust valve of the first piston device in the second embodiment; 22 - upper end plate of the cylinder block of the first piston device in the second embodiment; 23 - piston of the first piston device in the second embodiment; 24 - cylinder block of the first piston device in the second embodiment; 25 - lower end plate of the cylinder block of the first piston device in the second embodiment; 30 - piston of the second piston device; 31 - cylinder block of the second piston device; 32 - driving device of the second piston device; 33 - grating ruler of the second piston device; 34 - exhaust pipeline of the second piston device. Specific Embodiments

[0036] The following will describe in detail the embodiments of the present utility model. The examples of the embodiments are shown in the drawings, where the same or similar reference numerals represent the same or similar elements or elements with the same or similar functions throughout. The embodiments described below with reference to the drawings are exemplary and are only used to explain the present utility model and should not be construed as a limitation of the present utility model.

[0037] In the description of the present utility model, it should be understood that the orientation or positional relationship indicated by terms such as "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc. is based on the orientation or positional relationship shown in the drawings. It is only for the convenience of describing the present utility model and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation. Therefore, it should not be construed as a limitation to the present utility model.

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

[0039] In the present utility model, unless otherwise clearly specified and defined, terms such as "installation", "connection", "connection", "fixation", etc. should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or integrated; it can be a mechanical connection, an electrical connection or can communicate with each other; it can be directly connected, or indirectly connected through an intermediate medium, and can be the communication inside two elements or the interaction relationship between two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present utility model can be understood according to specific circumstances.

[0040] A calibration device for a ventilator detector provided by the present utility model is a measuring standard instrument for calibrating a respiratory detector, and is a metrological calibration device integrating 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, and can realize the calibration and traceability of static flow, static pressure, dynamic flow, dynamic parameters, inspiratory oxygen concentration, etc. of the ventilator detector.

[0041] Such as Figure 1As shown in the figure, the calibration device for a ventilator detector provided by an embodiment of the present utility model includes 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 intake pipelines of the first piston device (3) and the second piston device (5) respectively through a first three-way valve (2) and a second three-way valve (4). The pressure sensor (6) is connected in series with the second piston device (5) and is communicated with the ventilator detector to be calibrated (7) through a pipeline. On the pipeline at the rear end of the ventilator detector to be calibrated (7), a third three-way valve (8) is installed; the simulated lung (9) is connected to the ventilator detector to be calibrated (7) through the third three-way valve (8). The difference of the embodiment provided by the present utility model lies in the structure of the first piston device (3), Figure 2 and Figure 3 shown are two different first piston devices.

[0042] Referring Figure 2 , the first piston device includes one set or multiple sets of piston systems with the same structure. The piston system includes a cylinder block (11), a piston (10), a lower end plate (15), a driving device (17), and a grating scale. The piston (10), the cylinder block (11), and the lower end plate of the cylinder (15) together form a sealed working chamber. An intake pipeline (12) and an exhaust pipeline (16) are provided on the lower end cover of the cylinder. An intake valve (13) is provided on the intake pipeline (12), and an exhaust valve (14) is provided on the exhaust 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 one set of piston system, its cylinder volume needs to be greater than or equal to 100L. When the first piston device is two sets or more sets of piston systems with the same structure, the piston systems 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 generate a standard flow of gas. The multi-cylinder alternating operation mode is to divide the piston systems into two groups with equal numbers; during operation, the two groups of piston systems operate alternately to continuously generate a standard flow of gas, so as to realize the continuous generation of a stable large gas flow with a small cylinder volume and reduce the processing difficulty of the cylinder block.

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

[0044] The second piston device (5) includes a cylinder (31), a piston (30), a driving device (32) and a grating scale (33). The driving device (32) of the second piston device is connected to the piston (30) to drive the piston (30) to reciprocate in the cylinder (31) to simulate the breathing process; the air outlet (34) of the cylinder (31) is communicated with the inlet of the ventilator tester to be calibrated through a pipeline; the grating scale (33) is arranged on the driving device (32) to detect the displacement of the piston; the air outlet of the ventilator tester (5) to be calibrated is connected to the simulated lung (9) through a third three-way valve (8). Wherein, a pressure sensor (6) is further arranged on the connecting pipeline between the air outlet (34) of the cylinder and the air inlet of the ventilator tester (7) to be calibrated.

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

[0046] During the calibration of static flow parameters, the control module controls the first three-way valve (2) and the third three-way valve (8) to communicate with the atmosphere, and the piston of the first piston device (3) reciprocates to provide a standard gas flow. The first piston device can control the gas flow at 180 L / min, and the flow value can be traced back 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 ventilator tester to be calibrated, the third three-way valve (8) is communicated with the simulated lung (9), and the second piston device (5) simulates the breathing process with the reciprocating movement of the piston (30) in the cylinder. The second piston device (5) sends air to the ventilator tester (7) to be calibrated, and the gas enters the simulated lung (9) through the ventilator tester (7) to be calibrated.

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

[0049] When calibrating the peak airway pressure, the peak value of the pressure change of the cylinder during the entire gas supply process is recorded by the pressure sensor (6), that is, the peak airway pressure is obtained. When calibrating the positive end-expiratory pressure, a stable pressure is output by the first piston device, which is the positive end-expiratory pressure, and the gas supply pressure range is: ±6 kPa. When calibrating the mean airway pressure, that is, the average pressure of each piston gas supply / extraction movement, after sampling by the pressure sensor multiple times, it is calculated by the control module.

[0050] The oxygen concentration mixing module consists 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 the oxygen concentration of 21%, the control module controls the first three-way valve (2) and the second three-way valve (4) to communicate with the atmosphere; when calibrating the 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 communicate with the oxygen concentration mixing module, and controls the oxygen concentration mixing module through the control module to output oxygen concentrations of different concentrations according to the calibration requirements. After the pressure-reduced oxygen standard gas is connected to the air inlets of the first piston device (3) and the second piston device (5), 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 inlet pipelines of the first piston device and the second piston device, it is possible to calibrate the oxygen concentration while calibrating the dynamic flow rate and dynamic pressure parameters, improving the calibration efficiency.

[0051] The calibration device for the ventilator detector in this embodiment can calibrate the tidal volume, gas flow rate, inspiratory time, expiratory time, respiratory ratio, respiratory frequency, and minute ventilation volume of the dynamic flow rate parameters of the ventilator detector to be calibrated.

[0052] Reference Figure 3 , in the calibration device for the ventilator detector provided by an embodiment of the present invention, the first piston device includes one set or multiple sets of piston systems with the same structure. The piston system of the first piston device includes an upper end cover (22), a cylinder block (24), and a lower end cover (25) of the cylinder. The piston (23), the cylinder block (24), the upper end cover (22) of the cylinder, and the lower end cover (25) of the cylinder form two mutually sealed cavities. An intake pipeline and an outlet pipeline are provided on the lower end cover. An intake valve (20) is provided on the intake pipeline, and an outlet valve (21) is provided on the outlet pipeline. When calibrating the flow rate, the piston (23) moves back and forth, and both volume chambers can be measured, which can improve the stability and continuity of the gas flow rate.

[0053] The present utility model calibrates the static flow rate, dynamic flow rate, dynamic pressure, respiratory rate, and oxygen concentration of a ventilator detector according to JJF 1234-2018 "Ventilator Calibration Specification" and metrological calibration principles, and can achieve the following calibration parameters:

[0054] Flow rate range (static): (0~180) L / min, with a maximum allowable error not greater than ±0.5%;

[0055] Tidal volume range (dynamic): (0~2000) mL, with a maximum allowable error not greater than ±1%;

[0056] Respiratory rate: (5~80) times / min, with a maximum allowable error not greater than ±1%;

[0057] Positive end-expiratory pressure range: 0.1~6 kPa, with a maximum allowable error not greater than ±1% of the reading or ±30 Pa;

[0058] Peak airway pressure range: 0.1~6 kPa, with a maximum allowable error not greater than ±1% of the reading or ±30 Pa;

[0059] Temperature: 0~50 °C, with a maximum allowable error of ±0.1 °C;

[0060] Oxygen concentration range: 21%~100%, with a maximum allowable error not greater than ±0.65% (volume fraction).

[0061] In the description of this specification, the description with reference to terms such as "one embodiment", "some embodiments", "schematic embodiments", "examples", "specific examples", or "some examples" means that the specific features, structures, materials, or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present utility model. In this specification, the schematic expressions of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described can be combined in a suitable manner in any one or more embodiments or examples.

[0062] Although the embodiments of the present utility model have been shown and described, those of ordinary skill in the art can understand that various changes, modifications, substitutions, and variations can be made to these embodiments without departing from the principles and purposes of the present utility model, and the scope of the present utility model is defined by the claims and their equivalents.

Claims

1. Ventilator detector calibration device, characterized in that Comprising: 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 includes one set or multiple sets of piston systems with the same structure. The piston system includes a cylinder, a piston, a driving device, and a grating scale; the first piston device is connected to the ventilator to be calibrated through a pipeline; The second piston device includes a cylinder, a piston, a driving device, and a grating scale; The oxygen concentration mixing module is connected to the first piston device and the second piston device respectively through pipelines; 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; 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 arranged on the pipeline connecting the ventilator detector to be calibrated and the simulated lung; The oxygen concentration mixing module includes multiple oxygen standard gases with 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 ventilator detector to be calibrated, and is used for data acquisition, 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 ventilator detector to be calibrated.

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

3. The calibration device for a ventilator detector according to claim 1, characterized in that, The cylinder of the piston system 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.

4. The calibration device for a ventilator detector according to claim 1, wherein 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, wherein The cylinder volume of the second piston device is 2000 mL.

6. The ventilator detector calibration device according to any one of claims 1 to 5, characterized in that, The oxygen concentrations of the oxygen standard gases are 21%, 40%, 60%, 80%, and 99%.

Images