CN216207523U

CN216207523U - Mask dead space detection device

Info

Publication number: CN216207523U
Application number: CN202122879107.6U
Authority: CN
Inventors: 吴东; 张国良; 王增荣
Original assignee: Dong Rong Precision Instrument Co ltd
Current assignee: Dong Rong Precision Instrument Co ltd
Priority date: 2021-11-23
Filing date: 2021-11-23
Publication date: 2022-04-05
Anticipated expiration: 2031-11-23

Abstract

The utility model provides a mask dead cavity detection device.A simulation respirator is communicated with a mixed gas path, a breathing gas path is communicated with the mixed gas path, an expiration branch and an inspiration branch are communicated with a head die, and first CO is₂The analyzer is communicated with a breathing gas circuit, the auxiliary pump is communicated with the head die through a sampling gas circuit, and the second CO is₂The analyzer is communicated with the sampling gas circuit, and the head die is communicated with the auxiliary pump through an expiration bypass. When the gas circuit is in a suction state, the auxiliary pump synchronously leads a small amount of gas in the detection cavity to pass through the suction gas sampling tube, the sampling gas circuit, the collecting bottle and the second sheetSucking the gas into the second cylinder via the second pipe valve and the second gas path to the second CO₂In the analyzer, passing a second CO₂Analyzer for CO in gas₂Detecting the gas content to obtain the residual CO in the mask₂The content of gas.

Description

Mask dead space detection device

Technical Field

The utility model relates to the technical field of mask detection equipment, in particular to the technical field of mask dead cavity detection equipment.

Background

Mask dead space refers to the volume fraction of carbon dioxide gas re-inhaled in the previous exhalation and is used to assess the safety of use of the respiratory system and determine the performance of the PPE. When the mask is used for a dead cavity test, the mask is worn on a test head die, and an electric simulation respirator is adopted to carry out CO (carbon monoxide) test₂The mixed gas is inhaled into a respiratory trachea of the test head die and then exhaled by the mask, and simultaneously, the electric simulation respirator inhales air (atmosphere) outside the mask through the test head die and the mask, and continuously monitors and records the inhaled air at the oral and nasal positions in the mask and CO in the atmospheric environment outside the mask₂And (4) concentration, so that mask dead space detection is realized. Present common face guard dead chamber check out test set has only been equipped with an electronic simulation breathing machine usually, breathes the gas circuit and adopts same gas circuit with the sample gas circuit, consequently leads to face guard dead chamber testing result not very accurate to the gas circuit that leads to face guard dead chamber equipment lays the structure comparatively complicacy, has increased manufacturing cost.

SUMMERY OF THE UTILITY MODEL

The utility model provides a mask dead cavity detection device, which solves the problems that the mask dead cavity detection result of mask dead cavity detection equipment in the prior art is not very accurate, the gas circuit layout structure is complex, and the manufacturing cost is high.

The technical scheme of the utility model is realized as follows:

the mask dead cavity detection device comprises a head die and CO₂Flow control instrument, simulated respirator, auxiliary pump and first CO₂Analyzer, second CO₂The simulation respirator comprises an analyzer, a breathing gas circuit and a sampling gas circuit, wherein a mixed gas circuit is communicated on the simulation respirator, the breathing gas circuit is communicated with the mixed gas circuit, an expiration branch circuit and an inspiration branch circuit are arranged on the breathing gas circuit, the expiration branch circuit and the inspiration branch circuit are communicated with a head die, and CO is used for analyzing the breath of the simulation respirator₂The flow controller is communicated with the mixed gas circuit through a first one-way valve and first CO₂The analyzer is communicated with the breathing gas circuit, and the auxiliary pump is connected with the head die through a sampling gas circuitThe sampling gas circuit is provided with a second one-way valve and second CO₂The analyzer is communicated with the sampling gas circuit, the head die is communicated with the auxiliary pump through an expiration bypass, and a combined electromagnetic valve is arranged on the expiration bypass, the inspiration bypass and the expiration bypass.

Further, in the CO₂A compensation gas cylinder and a first CO are communicated between the flow controller and the first one-way valve₂The analyzer is communicated with the breathing gas circuit through a first gas circuit, a first pipe valve is arranged on the first gas circuit, and the second CO is₂The analyzer is communicated with the sampling gas circuit through a second gas circuit, a second pipe valve is arranged on the second gas circuit, and a collecting bottle is arranged on the sampling gas circuit between the second one-way valve and the second gas circuit.

Furthermore, the combined solenoid valve comprises a first expiration one-way solenoid valve, an inspiration one-way solenoid valve and a second expiration one-way solenoid valve, and the first expiration one-way solenoid valve, the inspiration one-way solenoid valve and the second expiration one-way solenoid valve are respectively communicated with the expiration branch, the inspiration branch and the expiration bypass.

Furthermore, the head die comprises a die shell, an exhaling pipe and an inhaled gas sampling pipe, an inwards-recessed detection cavity is arranged at the front part of the die shell, the exhaling pipe and the inhaled gas sampling pipe are fixedly arranged in the detection cavity in a penetrating mode, an exhalation hole is formed in the rear wall of the die shell detection cavity, the exhaling branch and the inhalation branch are communicated with the exhaling pipe, the sampling gas path is communicated with the inhaled gas sampling pipe, and the exhalation bypass is communicated with the exhalation hole.

Further, be equipped with the barrel on the mould shell detects the back wall in chamber, the exhalation pipe is located the mould shell, and a tip of exhalation pipe is fixed to be worn to establish in the barrel, is equipped with the coupling at another tip of exhalation pipe, inhale the gas sampling tube and be located the exhalation pipe, and the tip that inhales the gas sampling tube is worn out from the preceding tip of exhalation pipe, and another tip that inhales the gas sampling tube is worn out from the exhalation pipe that is located the mould shell and detects the chamber outside, is equipped with first connector at this tip that inhales the gas sampling tube, is equipped with the second connector in the expiratory hole department of detecting the chamber back wall, exhale the branch road and inhale the branch road and the coupling intercommunication of exhalation pipe, the sample gas circuit communicates with the first connector of inhaling the gas sampling tube, exhales the bypass and the second connector intercommunication of expiratory hole department.

Furthermore, the simulated breathing machine comprises a frame, a first cylinder body, a first piston rod and a linear push rod, the auxiliary pump comprises a second cylinder body, a second piston and a second piston rod, the first cylinder body and the second cylinder body are respectively and fixedly arranged on the frame, the top walls of the first cylinder body and the second cylinder body are respectively provided with a first air hole and a second air hole, the first piston and the second piston are respectively and movably clamped in the first cylinder body and the second cylinder body, the bottom walls of the first cylinder body and the second cylinder body are respectively provided with a through hole, the first piston rod and the second piston rod are respectively and movably arranged in the through holes in a penetrating way, the upper end parts of the first piston rod and the second piston rod are respectively and fixedly connected with the first piston and the second piston, the lower end parts of the first piston rod and the second piston rod are fixedly connected through a connecting plate, the linear push rod is fixedly arranged on the frame, and the telescopic rod of the linear push rod is fixedly connected with the connecting plate, the mixed gas circuit is communicated with a first gas hole of the first cylinder body, and the sampling gas circuit and the expiration bypass are communicated with a second gas hole of the second cylinder body.

Furthermore, the peripheral walls of the first piston and the second piston are respectively provided with an annular groove, sealing rings are clamped in the annular grooves of the first piston and the second piston, and the sealing rings are in contact with the inner peripheral walls of the first cylinder body and the second cylinder body.

The utility model adopts the technical proposal to achieve the following beneficial effects: the auxiliary pump and the simulation respirator are synchronously operated, when the gas circuit is in an inspiration state, the auxiliary pump synchronously sucks a small amount of gas in the detection cavity into the second cylinder body through the gas suction sampling tube, the sampling gas circuit, the collecting bottle and the second one-way valve, and in the process, a part of gas enters the second CO through the second tube valve and the second gas circuit₂In the analyzer 9, passing the second CO₂Analyzer for CO in gas₂Detecting the gas content to obtain the residual CO in the mask₂Content of gas, computer in obtaining test CO₂Gas concentration and residual CO in the mask₂After the content of the gas, the dead space assessment result of the mask to be tested is obtained through calculation, so that the breath is realizedThe gas suction path and the sampling gas path are separated, so that the detection precision of the dead cavity of the mask is improved, the structure of the dead cavity detection device of the mask is simplified, and the manufacturing cost is effectively reduced.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to the drawings without creative efforts.

FIG. 1 is a gas path diagram of the present invention;

FIG. 2 is a perspective view of the head die;

FIG. 3 is a cross-sectional view of the head die;

FIG. 4 is a perspective view of the front half of the head die;

FIG. 5 is a schematic view of the headgear after wearing the mask;

FIG. 6 is a perspective view of a simulated ventilator and auxiliary pump;

FIG. 7 is a cross-sectional view of a simulated ventilator and auxiliary pump;

fig. 8 is a partially enlarged schematic view of a portion a of fig. 7.

In the drawings, the parts corresponding to the reference numerals are as follows:

1-head die, 2-compensated cylinder, 3-CO₂Flow controller, 4-simulated respirator, 5-auxiliary pump, 6-collecting bottle, 7-combined electromagnetic valve, 8-first CO₂Analyzer, 9-second CO₂Analyzer, 10-first pipe valve, 11-second pipe valve, 12-first one-way valve, 13-first expiration one-way solenoid valve, 14-inspiration one-way solenoid valve, 15-second expiration one-way solenoid valve, 16-second one-way valve, 17-mould shell, 18-exhalation pipe, 19-inspiration gas sampling pipe, 20-detection cavity, 21-cylinder, 22-pipe joint, 23-first connecting joint, 24-expiration hole, 25-second connecting joint, 26-frame, 27-first cylinder, 28-first piston, 29-first piston rod, 30-sealing ring, 31-linear push rod, 32-second cylinder, 33-second piston, 34-second piston rod, 35-first piston rod-first air hole, 36-second air hole, 37-ring groove, 38-through hole, 39-connecting plate, 40-telescopic rod, 41-mask, 42-breathing air path, 43-breathing air path, 44-breathing air path, 45-mixed air path, 46-first air path, 47-breathing air path, 48-sampling air path, 49-second air path.

Detailed Description

The technical solutions of the present invention will be described clearly and completely with reference to the following embodiments of the present invention, and it should be understood that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

Referring to fig. 1, the mask dead space detection device comprises a head die 1 and a CO₂ Flow control instrument 3, simulation respirator 4, auxiliary pump 5 and first CO₂Analyzer 8, second CO₂The analyzer 9, the breathing gas circuit 42 and the sampling gas circuit 48, the simulation respirator 4 is communicated with a mixed gas circuit 45, the breathing gas circuit 42 is communicated with the mixed gas circuit 45, the breathing gas circuit 42 is provided with an expiration branch circuit 43 and an inspiration branch circuit 44, the expiration branch circuit 43 and the inspiration branch circuit 44 are communicated with the head die 1, and CO is introduced into the cavity of the mold₂The flow controller 3 is communicated with the mixed gas path 45 through the first one-way valve 12, and CO is filled in the mixed gas path₂A compensation gas cylinder 2 and a first CO are communicated between the flow controller 3 and the first one-way valve 12₂The analyzer 8 is connected to the breathing circuit 42 via a first circuit 46, and a first tube valve 10 is provided on the first circuit 46. The auxiliary pump 5 is communicated with the head die 1 through a sampling gas path 48, and a second one-way valve 16 and a second CO are arranged on the sampling gas path 48₂The analyzer 9 is communicated with the sampling gas path 48 through a second gas path 49, a second pipe valve 11 is arranged on the second gas path 49, and a collecting bottle 6 is arranged on the sampling gas path 48 between the second one-way valve 16 and the second gas path 49. The head die 1 is communicated with the auxiliary pump 5 through an expiration bypass 47, a combined electromagnetic valve 7 is arranged on the expiration bypass 43, the inspiration bypass 44 and the expiration bypass 47, the combined electromagnetic valve 7 comprises a first expiration one-way electromagnetic valve 13, an inspiration one-way electromagnetic valve 14 and a second expiration one-way electromagnetic valve 15, and the first expiration one-way electromagnetic valveThe valve 13, the inspiration one-way solenoid valve 14 and the second expiration one-way solenoid valve 15 are in communication with the expiration branch 43, the inspiration branch 44 and the expiration bypass 47, respectively.

The specific structure of the head die 1 and the specific communication relationship among the expiration branch 43, the inspiration branch 44, the expiration bypass 47 and the sampling air passage 48 are as follows: referring to fig. 2 to 5, the head die 1 includes a die shell 17, an exhalation tube 18 and an inhaled gas sampling tube 19, an inwardly recessed detection cavity 20 is provided at the front of the die shell 17, the exhalation tube 18 and the inhaled gas sampling tube 19 are fixedly inserted into the detection cavity 20, an exhalation vent 24 is provided on the rear wall of the detection cavity 20 of the die shell 17, the exhalation branch 43 and the inhalation branch 44 are communicated with the exhalation tube 18, the sampling gas path 48 is communicated with the inhaled gas sampling tube 19, and the exhalation bypass 47 is communicated with the exhalation vent 24. The communication relationship between the expiratory branch 43 and the inspiratory branch 44 and the expiratory tube 18, the specific communication relationship between the sampling air path 48 and the inspiratory gas sampling tube 19, and the specific communication relationship between the expiratory bypass 47 and the expiratory hole 24 are as follows: a cylinder 21 is arranged on the rear wall of the detection cavity 20 of the mould shell 17, the exhalation tube 18 is positioned in the mould shell 17, one end part of the exhalation tube 18 is fixedly arranged in the cylinder 21 in a penetrating way, a pipe joint 22 is arranged at the other end of the exhaling pipe 18, the inhaled gas sampling pipe 19 is positioned in the exhaling pipe 18, one end of the inhaled gas sampling pipe 19 penetrates out from the front end of the exhaling pipe 18, the other end of the inhaled gas sampling pipe 19 penetrates out from the exhaling pipe 18 positioned outside the detection cavity 20 of the mould shell 17, a first connector 23 is provided at the end of the suction gas sampling tube 19, a second connector 25 is provided at the exhalation port 24 of the rear wall of the detection chamber 20, the expiration branch 43 and the inspiration branch 44 are communicated with the pipe joint 22 of the expiration pipe 18, the sampling air passage 48 is communicated with the first joint 23 of the inspiration gas sampling pipe 19, and the expiration bypass 47 is communicated with the second joint 25 at the expiration hole 24.

The specific structures of the simulated ventilator 4 and the auxiliary pump 5, and the specific communication relations with the mixing gas circuit 45, the sampling gas circuit 48 and the expiration bypass 47 are as follows: referring to fig. 6 to 8, the simulated breathing apparatus 4 includes a frame 26, a first cylinder 27, a first piston 28, a first piston rod 29 and a linear push rod 31, the auxiliary pump 5 includes a second cylinder 32, a second piston 33 and a second piston rod 34, the first cylinder 27 and the second cylinder 32 are respectively and fixedly mounted on the frame 26, a first air hole 35 and a second air hole 36 are respectively opened on the top wall of the first cylinder 27 and the second cylinder 32, the first piston 28 and the second piston 33 are respectively and movably clamped in the first cylinder 27 and the second cylinder 32, annular grooves 37 are respectively provided on the outer circumferential walls of the first piston 28 and the second piston 33, sealing rings 30 are clamped in the annular grooves 37 of the first piston 28 and the second piston 33, the sealing rings 30 are in contact with the inner circumferential walls of the first cylinder 27 and the second cylinder 32, through holes 38 are respectively provided on the bottom walls of the first cylinder 27 and the second cylinder 32, the first piston rod 29 and the second piston rod 34 are movably arranged in the through hole 38 in a penetrating mode respectively, the upper end portions of the first piston rod 29 and the second piston rod 34 are fixedly connected with the first piston 28 and the second piston 33 respectively, the lower end portions of the first piston rod 29 and the second piston rod 34 are fixedly connected through a connecting plate 39, the linear push rod 31 is fixedly installed on the rack 26, the telescopic rod 40 of the linear push rod 31 is fixedly connected with the connecting plate 39, the mixed gas circuit 45 is communicated with the first gas hole 35 of the first cylinder 27, and the sampling gas circuit 48 and the expiration bypass 47 are communicated with the second gas hole 36 of the second cylinder 32.

The working principle of the mask dead cavity detection device is as follows: introducing CO₂Flow controller 3 and CO₂The air source is communicated, the face mask 41 is correctly worn on the head die 1 and covers the front side of the detection cavity 20, and the periphery of the face mask 41 is sealed with the head die 1; and starting the computer software to detect. The first piston 28 of the simulated breathing machine 4 is driven to move downwards by the linear push rod 31, so that the air passage is in an inspiration state, and at the moment, CO is in a CO (carbon monoxide) state₂CO of gas source₂Gas flow through CO₂The flow controller 3, the compensation gas cylinder 2, the first one-way valve 12 and the mixed gas circuit 45 are sucked into the first cylinder 27 of the simulated respirator 4, meanwhile, the atmosphere outside the head model 1 penetrates through the face mask 41 and flows through the detection cavity 20, the exhalation pipe 18, the inspiration branch 44, the inspiration one-way solenoid valve 14, the breathing gas circuit 42 and the mixed gas circuit 45 and is sucked into the first cylinder 27 of the simulated respirator 4, and CO is absorbed into the first cylinder 27 of the simulated respirator 4₂The gas and the atmosphere are mixed by the mixed gas path 45 to form a mixed gas to be stored in the first cylinder 27.

Through a control circuitThe combination electromagnetic valve 7 is controlled to change direction to enable the air path to be in an exhalation state, at the moment, the first piston 28 of the simulated breathing machine 4 is driven to move upwards through the linear push rod 31, the mixed gas stored in the first cylinder 27 is pushed out and flows through the mixed gas path 45, the breathing gas path 42, the first exhalation one-way electromagnetic valve 13, the exhalation branch 43, the exhalation pipe 18 and the detection cavity 20 to be exhaled to the atmosphere through the mask 41, and at the same time, a small part of the mixed gas flows through the first pipe valve 10 and the first air path 46 to enter the first CO after being exhausted from the mixed gas path 45₂In the analyzer 8, by the first CO₂Analyzer 8 for CO in mixed gas₂Detecting the gas concentration to obtain test CO₂The gas concentration.

When the first piston 28 of the simulated respirator 4 moves, the second piston 33 of the auxiliary pump 5 synchronously acts, when the air path is in an inspiration state, the auxiliary pump 5 synchronously inhales a small amount of gas in the detection cavity 20 into the second cylinder 32 through the inhaled gas sampling pipe 19, the sampling air path 48, the collecting bottle 6 and the second one-way valve 16, and in the process, a part of gas enters the second CO through the second pipe valve 11 and the second air path 49₂In the analyzer 9, passing the second CO₂Analyzer 9 for CO in gas₂Detecting the gas content to obtain the residual CO in the face mask 41₂The content of gas. Computer-in-process CO acquisition test₂Gas concentration and residual CO in the mask₂After the gas content, the dead space assessment of the measured mask 41 is calculated. When the air passage is in an exhalation state, the second piston 33 of the auxiliary pump 5 pushes out the air in the second cylinder 32, and the air flows through the second exhalation one-way solenoid valve 15, the exhalation bypass 47, the exhalation port 24 and the detection chamber 20, and then is exhaled to the atmosphere through the mask 41.

The above description is only for the purpose of illustrating the preferred embodiments of the present invention and is not to be construed as limiting the utility model, and any modifications, equivalents, improvements and the like that fall within the spirit and principle of the present invention are intended to be included therein.

Claims

1. The mask dead cavity detection device is characterized by comprising a head die (1) and CO₂Flow rateA control instrument (3), a simulation respirator (4), an auxiliary pump (5) and a first CO₂Analyzer (8), second CO₂Analysis appearance (9), breathing gas circuit (42) and sample gas circuit (48) the intercommunication has mixed gas circuit (45) on simulation breathing machine (4), breathes gas circuit (42) and mixes gas circuit (45) intercommunication, is equipped with on breathing gas circuit (42) and exhales branch road (43) and inhale branch road (44), exhales branch road (43) and inhale branch road (44) and head mould (1) intercommunication, CO₂The flow controller (3) is communicated with the mixed gas circuit (45) through a first one-way valve (12), and first CO is₂The analyzer (8) is communicated with the breathing gas circuit (42), the auxiliary pump (5) is communicated with the head die (1) through a sampling gas circuit (48), a second one-way valve (16) is arranged on the sampling gas circuit (48), and second CO is₂The analyzer (9) is communicated with a sampling gas circuit (48), the head die (1) is communicated with the auxiliary pump (5) through an expiration bypass (47), and a combined electromagnetic valve (7) is arranged on the expiration bypass (43), the inspiration bypass (44) and the expiration bypass (47).

2. The mask dead space detection device of claim 1, wherein the CO is present in the chamber₂A compensation gas cylinder (2) is communicated between the flow controller (3) and the first one-way valve (12), and first CO is₂The analyzer (8) is communicated with the breathing gas circuit (42) through a first gas circuit (46), a first pipe valve (10) is arranged on the first gas circuit (46), and the second CO is₂The analyzer (9) is communicated with the sampling gas circuit (48) through a second gas circuit (49), a second pipe valve (11) is arranged on the second gas circuit (49), and a collecting bottle (6) is arranged on the sampling gas circuit (48) between the second one-way valve (16) and the second gas circuit (49).

3. The mask dead space detection device according to claim 1, characterized in that the combined solenoid valve (7) comprises a first exhalation one-way solenoid valve (13), an inhalation one-way solenoid valve (14) and a second exhalation one-way solenoid valve (15), the first exhalation one-way solenoid valve (13), the inhalation one-way solenoid valve (14) and the second exhalation one-way solenoid valve (15) being in communication with the exhalation branch (43), the inhalation branch (44) and the exhalation bypass (47), respectively.

4. The mask dead space detection device according to claim 1, wherein the head die (1) comprises a mold shell (17), an exhalation tube (18) and an inhalation gas sampling tube (19), an inwardly recessed detection chamber (20) is provided in front of the mold shell (17), the exhalation tube (18) and the inhalation gas sampling tube (19) are fixedly inserted into the detection chamber (20), an exhalation vent (24) is provided on a rear wall of the detection chamber (20) of the mold shell (17), the exhalation branch (43) and the inhalation branch (44) are communicated with the exhalation tube (18), the sampling gas path (48) is communicated with the inhalation gas sampling tube (19), and the exhalation bypass (47) is communicated with the exhalation vent (24).

5. The mask dead space detection device according to claim 4, wherein a cylinder (21) is provided on a rear wall of the detection chamber (20) of the mold case (17), the exhalation tube (18) is located in the mold case (17), one end of the exhalation tube (18) is fixedly inserted into the cylinder (21), a tube connector (22) is provided at the other end of the exhalation tube (18), the inhalation gas sampling tube (19) is located in the exhalation tube (18), one end of the inhalation gas sampling tube (19) is inserted from a front end of the exhalation tube (18), the other end of the inhalation gas sampling tube (19) is inserted from the exhalation tube (18) located outside the detection chamber (20) of the mold case (17), a first connector (23) is provided at the end of the inhalation gas sampling tube (19), a second connector (25) is provided at an exhalation hole (24) in the rear wall of the detection chamber (20), the exhalation branch (43) and the inhalation branch (44) are communicated with the tube connector (22) of the exhalation tube (18) The sampling air passage (48) is communicated with a first connector (23) of the inhalation gas sampling tube (19), and the expiration bypass (47) is communicated with a second connector (25) at the expiration hole (24).

6. The mask dead space detection device according to claim 1, wherein the simulated breathing machine (4) comprises a frame (26), a first cylinder (27), a first piston (28), a first piston rod (29) and a linear push rod (31), the auxiliary pump (5) comprises a second cylinder (32), a second piston (33) and a second piston rod (34), the first cylinder (27) and the second cylinder (32) are respectively and fixedly installed on the frame (26), the top walls of the first cylinder (27) and the second cylinder (32) are respectively provided with a first air hole (35) and a second air hole (36), the first piston (28) and the second piston (33) are respectively and movably clamped in the first cylinder (27) and the second cylinder (32), the bottom walls of the first cylinder (27) and the second cylinder (32) are respectively provided with a through hole (38), and the first piston rod (29) and the second piston rod (34) are respectively and movably inserted in the through hole (38), the upper end parts of the first piston rod (29) and the second piston rod (34) are respectively fixedly connected with the first piston (28) and the second piston (33), the lower end parts of the first piston rod (29) and the second piston rod (34) are fixedly connected through a connecting plate (39), the linear push rod (31) is fixedly installed on the rack (26), the telescopic rod (40) of the linear push rod (31) is fixedly connected with the connecting plate (39), the mixed gas circuit (45) is communicated with the first air hole (35) of the first cylinder body (27), and the sampling gas circuit (48) and the expiration bypass (47) are communicated with the second air hole (36) of the second cylinder body (32).

7. The mask dead space detection device according to claim 6, wherein the outer peripheral walls of the first piston (28) and the second piston (33) are respectively provided with an annular groove (37), and a seal ring (30) is snap-fitted into the annular groove (37) of the first piston (28) and the second piston (33), and the seal ring (30) is in contact with the inner peripheral walls of the first cylinder (27) and the second cylinder (32).