CN115154946B - Noise reduction, damping and air supply device applied to air breathing mask - Google Patents

Abstract

The utility model relates to the field of respirator accessory, especially, relate to a be applied to making an uproar falls of air respirator, damping, air feeder, including can dismantling the face guard breathing joint of connecting in respirator, communicate in face guard breathing joint and to the gaseous air supply hose in the face guard breathing joint input gas cylinder, locate the flow control device that face guard breathing joint just was used for adjusting face guard breathing joint to the velocity of flow of respirator carrier gas, flow control device is including locating the joint inner piece in the face guard breathing joint, rotate the adjustment sheet of connecting in the joint inner piece, locate the outside joint outer block of face guard breathing joint, locate the joint outer block and control adjustment sheet and connect the pivoted adjustment mechanism of joint inner piece mutually, the gas pocket that has several one-to-one correspondence is all run through to set up to adjustment sheet and joint inner piece, possess the control of carrying out the adjustment sheet on the joint outer block, need not dismantle the face guard breathing joint and carry out flow control, comparatively convenient effect.

Description

Noise reduction, damping and air supply device applied to air breathing mask

Technical Field

The application relates to the field of respirator accessories, in particular to a noise reduction, damping and air supply device applied to an air breathing mask.

Background

When fire extinguishing work or some emergency work with poor air environment is carried out, an air respirator is needed to be used for working, so that related operators do not depend on outside air to carry out operation. The air respirator generally comprises a breathing mask worn by a user, an air cylinder for storing compressed air inside, and an air supply device for supplying the air in the air cylinder into the breathing mask at a proper flow rate so as to enable the user to breathe normally.

The existing noise reduction, damping and air supply device applied to the air breathing mask is CN112933452A, a cavity is arranged inside a mask breathing joint, a flow guide nozzle sleeve is arranged outside an air supply hose, a noise reduction damping filter screen is arranged in the flow guide nozzle, the flow guide nozzle is arranged in the cavity of the mask breathing joint, the rear end of the flow guide nozzle is connected with the mask breathing joint in a clamping mode, a flow regulation damping blade is arranged in front of the flow guide nozzle, and the rear end of the mask breathing joint is connected with a valve cover.

To the correlation technique among the above-mentioned, flow control damping blade can run through and set up the several notch and flow through for the air, because flow control damping blade is located the water conservancy diversion mouth for when needing to carry out flow control, will take off face guard breathing joint from respirator, then can change flow control damping blade so that the open area who corresponds the notch obtains changing, have respirator and air feeder installation completion back flow control comparatively inconvenient defect.

Disclosure of Invention

In order to facilitate the flow regulation after respirator and air feeder installation are accomplished, this application provides one kind and is applied to making an uproar, damping, air feeder of falling of air respirator.

The application provides a be applied to making an uproar, damping, air feeder that falls of air respirator adopts following technical scheme.

The utility model provides a be applied to making an uproar, damping, air feeder that falls of air respirator, including can dismantle connect in the face guard breathing joint of breathing face guard, communicate in the face guard breathing joint and to face guard breathing joint in the gaseous air supply hose of input gas cylinder, locate the face guard breathing joint and be used for adjusting the flow regulator that face guard breathing joint carried gaseous velocity to breathing face guard, flow regulator connects the outside joint ectosome of outside, locates the joint ectosome of face guard breathing joint and control the regulation piece and to the joint ectosome pivoted adjustment mechanism of breathing face guard including locating the joint ectosome of face guard breathing joint, rotation, the regulation piece that connects in the joint ectosome, all runs through to set up the gas pocket that has several phase one-to-one.

Through adopting above-mentioned technical scheme, carry out controlling of adjustment sheet on connecting the outer piece for the adjustment sheet can rotate to the joint inner piece mutually, makes the gas pocket of adjustment sheet and the area that connects the gas pocket alignment intercommunication of inner piece appear changing, adjusts with the air velocity that the face guard breathing joint entered into to the respirator in, need not take off the face guard breathing joint from the respirator again and carries out flow control, and is comparatively convenient.

Optionally, the adjusting mechanism includes an outer ring rack fixedly connected to the circumferential outer wall of the adjusting piece, an outer ring gear rotatably connected to the joint outer block and meshed with the outer ring rack, and a knob coaxially and fixedly connected to the outer ring gear and exposed out of the joint outer block.

Through adopting above-mentioned technical scheme, rotate the knob for the outer piece internal gear carries out synchronous rotation, makes the outer lane rack rotate, makes the adjustment sheet can carry out synchronous rotation, so that control the adjustment sheet.

Optionally, the joint outer block is slidably connected with the rotation limiting rubber block, the knob is fixedly connected with the knob rubber block which can be tightly attached to the rotation limiting rubber block, and the joint outer block is provided with a pushing spring which pushes the rotation limiting rubber block to move towards the knob rubber block.

Through adopting above-mentioned technical scheme for after the knob is adjusted to suitable position, promote the spring and can force the restriction to change the block rubber and support tightly in the knob block rubber, make the knob difficult random rotation again, in order to reduce after adjusting the completion, the mistake of external to the knob bumps and makes the face guard breathing joint send into the possibility that the change appears in the air velocity of respirator.

Optionally, two end faces of the portion, located in the joint outer block, of the adjusting sheet are coaxially and fixedly connected with sealing rings, and the sealing rings are tightly and coaxially connected to the joint outer block in a rotating mode.

Through adopting above-mentioned technical scheme, the sealing ring reduces the face guard breathing and connects the interior possibility that carries out the air current exchange through connecting the outer piece, also can make the lubricating oil of outer lane rack and outer piece internal gear department difficult for entering into the face guard breathing and connect in for the gas quality that breathing face guard was sent into to the face guard breathing connects is difficult for receiving the influence.

Optionally, the outer ring rack is arc-shaped, the two ends of the outer ring rack are fixedly connected with the rotation limiting pieces, and the process of one rotation limiting piece from being attached to the outer internal gear to being far away from the outer internal gear corresponds to the process of communicating the air holes of the adjusting pieces and the air holes of the joint inner pieces from alignment to dislocation.

Through adopting above-mentioned technical scheme for the rotation of knob can obtain a better control to the velocity of flow that face guard breathing joint sent into gas to respirator, and the knob that is difficult for appearing rotates excessively, but the velocity of flow does not have the condition of too much change.

Optionally, a staggered hole piece is arranged at one side of the joint inner piece, which is far away from one end of the air supply hose communicated with the mask breathing joint, and the staggered hole piece penetrates through a plurality of speed reducing holes which are staggered with each air hole of the joint inner piece.

Through adopting above-mentioned technical scheme for in the difficult direct entry to respirator of gas that the follow joint inner sheet was sent out, but can strike earlier on the dislocation hole piece in order to reach the effect that reduces the gas flow rate, make respirator's the person of wearing's breathing more comfortable.

Optionally, the dislocation hole piece is corresponding to the equal fixedly connected with round platform pipe in the position department in each slow speed hole, and the round platform pipe is located the side department that the dislocation hole piece faces the joint inner piece, and the internal diameter that the round platform pipe kept away from dislocation hole piece one end is less than the internal diameter that the round platform pipe is close to dislocation hole piece one end.

By adopting the technical scheme, the airflow impacting on the dislocation hole piece can enter the breathing mask only after entering the dislocation hole through the circular truncated cone tube, so that the speed of the airflow entering the breathing mask is further reduced.

Optionally, a flow adjustment damping blade is arranged at one side of the joint inner sheet, which faces to one end of the air supply hose communicating with the mask breathing joint, and one end of the air supply hose in the mask breathing joint faces to one side, which is away from the joint inner sheet, of the flow adjustment damping blade.

Through adopting above-mentioned technical scheme, adjust the more than one big range department of the velocity of flow that normal people is fit for with flow control damping blade to carry out a preliminary regulation to the gas velocity of flow, make the adjustment of adjustment sheet cooperation joint inner sheet can be more effectual carry out the secondary velocity of flow regulation, also help further reducing to send into the gas velocity of flow in the respirator.

Optionally, the mask breathing connects and can dismantle near air feed hose one end and be connected with the valve gap, and air feed hose wears to establish and fixed connection in the valve gap, and air feed hose is equipped with the water conservancy diversion mouth towards the one end of mask breathing connects, and the water conservancy diversion mouth is located inside the mask breathing connects, and it falls the damping filter screen of making an uproar to press from both sides tightly between the close terminal surface of water conservancy diversion mouth and air feed hose.

Through adopting above-mentioned technical scheme, so that when adjusting the knob to the gas flow rate is the biggest, the user still feels the gas flow rate all the time when too little, can with dismantle between the face guard breathing joint box valve gap, then adjust the flow control damping blade, make the gas flow rate maximum range value that the knob can be adjusted obtain certain promotion, fall the damping filter screen of making an uproar and can play certain filtering action to gas, it enters into the face guard breathing joint to reduce magazine, and the setting up of water conservancy diversion mouth makes and falls the damping filter screen of making an uproar and also can dismantle comparatively conveniently and change or clear up.

Optionally, the inner wall of the face mask breathing joint is slidably connected with a supporting block, the flow guide nozzle is abutted against the supporting block, and a supporting block spring forcing the supporting block to move towards one end, far away from the face mask breathing joint, of the valve cover is arranged in the face mask breathing joint.

Through adopting above-mentioned technical scheme, assembly between face guard breathing joint and the water conservancy diversion mouth and the assembly looks adaptation of water conservancy diversion mouth and air feed hose, otherwise appear falling the damping filter screen of making an uproar easily and become flexible or receive the too big condition of pressure to appear, and support the setting up of piece and make even the assembly precision is not so high, fall the damping filter screen of making an uproar and also be difficult for appearing not flexible or the too big condition of pressure that receives.

In summary, the present application includes at least one of the following benefits:

1. the mask breathing joint does not need to be taken down from the breathing mask for flow adjustment, so that convenience is brought;

2. adjust the more big little scope department of velocity of flow that normal people is fit with flow control damping blade to carry out a preliminary regulation to the gas velocity of flow, make the adjustment of the second velocity of flow that can more effectual carry out of adjustment piece cooperation joint inner sheet, also help further reducing to send into the gas velocity of flow in the respirator.

Drawings

FIG. 1 is a schematic cross-sectional view of a mask breathing fitting, air supply hose, valve cover and cover plate of the present application;

FIG. 2 is an enlarged view at A in FIG. 1;

FIG. 3 is another perspective of FIG. 1 to show a structural schematic view of the adjustment mechanism;

fig. 4 is another view of fig. 1 to show the structure of the circular truncated cone tube.

Description of the reference numerals: 1. a mask breathing joint; 2. an air supply hose; 21. a gas passing port; 22. a cover plate; 3. a flow regulating device; 31. a step opening; 32. an end ring; 33. a filter screen port; 34. an end ring hole; 35. a limiting ring; 36. a resisting block; 37. a resisting block spring; 38. a guide rod; 39. a supporting block chute; 4. a joint inner sheet; 41. a seal ring; 42. a rotation limiting sheet; 43. dislocation hole sheets; 44. a retarding hole; 45. flow regulating damping vanes; 46. a valve cover; 47. a flow guide nozzle; 48. a circular truncated cone tube; 49. a noise reduction damping filter screen; 5. a regulating sheet; 51. a joint outer block; 52. an adjustment mechanism; 53. air holes; 54. an outer ring rack; 55. an outer ring gear; 56. a knob; 57. limiting rotation of the rubber block; 58. a knob rubber block; 59. pushing the spring.

Detailed Description

The present application is described in further detail below with reference to the attached drawings.

The embodiment of the application discloses be applied to making an uproar falls in air respirator, damping, air feeder, refer to fig. 1, including one end closely peg graft in respirator's face guard breathing joint 1, face guard breathing joint 1 both ends run through, the coaxial threaded connection of one end circumference outer wall that respirator was kept away from to face guard breathing joint 1 has valve gap 46, valve gap 46 both ends run through, valve gap 46 keeps away from the inseparable joint of face guard breathing joint 1 one end and has apron 22, face guard breathing joint 1 is close to the coaxial fixedly connected with spacing ring 35 of one end circumference outer wall of valve gap 46, valve gap 46 terminal surface butt is in spacing ring 35, make valve gap 46 and face guard breathing joint 1 between be difficult for the rotation excessively. Valve gap 46 circumference outer wall radially wears to establish and fixedly connected with air supply hose 2 along self, and air supply hose 2 exposes valve gap 46's part and is the flexible hose, and air supply hose 2 is located the part of valve gap 46 and is the difficult PE hard tube that takes place deformation, and the shaft of pipe that air supply hose 2 is located valve gap 46 is 90 degrees crooked for 2 tip axis of air supply hose are unanimous with valve gap 46 circumference inner wall axis, and 2 open ends of air supply hose are located face guard breathing and connect 1.

Referring to fig. 1 and 2, a step opening 31 is coaxially opened at the end of the breathing joint 1 facing the valve cover 46, and the step opening 31 is communicated with the circumferential inner wall of the breathing joint 1. Install the water conservancy diversion mouth 47 that the axis is the same in the face guard breathing joint 1, the coaxial integrated into one piece of one end circumference outer wall that water conservancy diversion mouth 47 is close to air supply hose 2 has an end ring 32, end ring 32 closely pegs graft in step mouth 31 along self axis, the circumference inner wall of face guard breathing joint 1 has evenly seted up several around self axis and has supported a spout 39, it is unanimous with face guard breathing joint 1 axis direction to support a spout 39 length direction, every supports a spout 39 and has supports piece 36 along self length direction sliding connection, it can be made for oily nylon that coefficient of friction is low to support piece 36, make support piece 36 when the use that does not need lubricating oil, also can keep a comparatively smooth and easy slip. The abutting blocks 36 are uniformly arranged around the circumferential inner wall of the mask breathing joint 1, guide rods 38 are fixedly connected to the inner wall of an abutting block sliding groove 39 corresponding to each abutting block 36, each guide rod 38 penetrates through the corresponding abutting block 36 along the axis of the circumferential inner wall of the mask breathing joint 1, the abutting blocks 36 are L-shaped, one end, exposed out of the mask breathing joint 1, of each abutting block 36 abuts against the end face, facing the flow guide nozzle 47, of the end ring 32, abutting block springs 37 penetrate through each guide rod 38, and the abutting blocks 36 are forced to move towards the end ring 32 by the abutting block springs 37.

Referring to fig. 1, the end face of the diversion nozzle 47 facing the air supply hose 2 is coaxially provided with a filter screen port 33, a noise reduction damping filter screen 49 is slidably connected in the filter screen port 33 along the axis direction thereof, and the number of the noise reduction damping filter screens 49 can be 200. One end of the air supply hose 2 is tightly inserted into the filter screen port 33 and abuts against the noise reduction damping filter screen 49, so that when the mask breathing joint 1 is screwed down from the valve cover 46, the flow guide nozzle 47 can be conveniently taken down from the air supply hose 2, and the noise reduction damping filter screen 49 can be conveniently taken down. The end ring 32 has an end ring hole 34 formed therethrough so that a portion of the gas supplied from the mouthpiece 47 to the mask breathing connector 1 can flow to the valve cover 46.

Referring to fig. 1, a flow adjustment damping blade 45 is installed at a position close to one end of the diversion nozzle 47 far from the end ring 32 in the mask breathing joint 1, the flow adjustment damping blade 45 is close to an opening of the diversion nozzle 47 at the end where the gas is delivered, so that the flow adjustment damping blade 45 can block the gas delivered by the diversion nozzle 47, meanwhile, the end surface of the flow adjustment damping blade 45 uniformly penetrates through and is provided with a plurality of gas passing ports 21, so that the flow rate of the gas delivered by the diversion nozzle 47 through the mask breathing joint 1 is adjusted to a certain extent, and the flow adjustment damping blade 45 is generally adjusted to be a larger maximum value of the proper gas flow rate of a normal person. The flow adjusting damping blade 45 is coaxially screwed on the inner circumferential wall of the mask breathing joint 1. When the end face of the end ring 32 abuts against the end face of the step opening 31, a distance exists between the flow guide nozzle 47 and the flow rate adjusting damping blade 45, so that the flow guide nozzle 47 cannot be completely blocked by the flow rate adjusting damping blade 45.

Referring to fig. 1 and 3, one side that flow control damping blade 45 deviates from water conservancy diversion mouth 47 is installed and is connected inner 4, connect the coaxial fixed connection of inner 4 in 1 circumference inner wall of face guard breathing joint, connect the inner 4 butt in the terminal surface that flow control damping blade 45 deviates from water conservancy diversion mouth 47, connect the inside coaxial rotation of inner 4 and be connected with adjustment sheet 5, several gas pocket 53 has all been seted up with connecting inner 4 to adjustment sheet 5, the side that gas pocket 53 was seted up to adjustment sheet 5 and joint inner 4 is hugged closely mutually, the gas pocket 53 of adjustment sheet 5 and the gas pocket that connects inner 4 can the intercommunication of aligning one by one. The flow regulating damping vanes 45 initially control the gas flow rate and then the adjustment flap 5 is adjusted by the wearer of the respirator to regulate the gas flow rate to suit.

Referring to fig. 3, the outer circumferential wall of the mask breathing joint 1 is coaxially and fixedly connected with a joint outer block 51, the circumference of the adjusting blade 5 is located in the joint outer block 51, the joint outer block 51 is provided with an adjusting mechanism 52 for controlling the adjusting blade 5 to rotate relative to the joint inner blade 4, the adjusting mechanism 52 comprises an outer ring rack 54 coaxially and fixedly connected with the outer circumferential wall of the adjusting blade 5, the outer ring rack 54 is meshed with an outer ring internal gear 55 rotatably connected inside the joint outer block 51, and the outer ring internal gear 55 is coaxially and fixedly connected with a knob 56 exposed on the end surface of the joint outer block 51. The two ends of the outer ring rack 54 are fixedly connected with the rotation limiting sheets 42 which can be abutted to the outer ring gear 55, when the knob 56 rotates, in the process that the outer ring gear 55 is changed from the state of being abutted to one rotation limiting sheet 42 to the state of being abutted to the other rotation limiting sheet 42, the air hole 53 of the joint inner sheet 4 and the air hole 53 of the adjusting sheet 5 are also changed from the dislocation communication to the completely aligned communication state, so that the air flow passing through the adjusting sheet 5 and the joint inner sheet 4 is controlled.

Referring to fig. 1 and 3, the two end faces of the adjusting piece 5 are both coaxially and fixedly connected with sealing rings 41, and the sealing rings 41 are connected to the joint outer block 51 in a sealing and rotating manner, so that lubricating oil between the outer ring rack 54 and the outer block inner gear 55 is difficult to enter the mask breathing joint 1, and the quality of gas sent into the breathing mask is improved. Connect outer piece 51 to set up the terminal surface department rotation of knob 56 and connect limited rotation block rubber 57, the coaxial fixedly connected with knob block rubber 58 of knob 56, limit rotation block rubber 57 and connect fixedly connected with between outer piece 51 and promote spring 59, promote spring 59 and can be the torsional spring, promote spring 59 and force limit rotation block rubber 57 and support in knob block rubber 58 tightly for knob 56 is difficult for the rethread after the adjustment finishes.

Referring to fig. 3 and 4, the one side department that connects inner sheet 4 and deviates from water conservancy diversion mouth 47 installs dislocation hole piece 43, dislocation hole piece 43 evenly runs through and has seted up several slow speed hole 44, dislocation hole piece 43 is towards the side fixedly connected with several round platform pipe 48 of connecting inner sheet 4, each round platform pipe 48 all corresponds and communicates in a slow speed hole 44, the one end internal diameter that round platform pipe 48 kept away from dislocation hole piece 43 is less than the one end internal diameter that round platform pipe 48 is close to dislocation hole piece 43, whole round platform pipe 48 and the gas pocket 53 homogeneous phase dislocation of connecting inner sheet 4, make from the difficult direct dislocation hole piece 43 that passes through of gas of connecting inner sheet 4, make the gas flow rate of sending into respiratory mask difficult too fast.

The implementation principle of the noise reduction, damping and air supply device applied to the air breathing mask in the embodiment of the application is as follows: the air supply hose 2 inputs air, the air firstly passes through the noise reduction damping filter screen 49, then part of the air passes through the flow regulation damping blade 45, then passes through the joint inner sheet 4, then passes through the circular truncated cone pipe 48 and the slow speed hole 44, and finally is sent into the breathing mask.

The above are preferred embodiments of the present application, and the scope of protection of the present application is not limited thereto, so: all equivalent changes made according to the structure, shape and principle of the present application shall be covered by the protection scope of the present application.

Claims (7)

1. The utility model provides a be applied to making an uproar, damping, air feeder that falls of air respirator, connects (1) including can dismantling the face guard breathing that connects in respirator, communicates in face guard breathing joint (1) and to face guard breathing joint (1) in gaseous air supply hose (2) of input gas cylinder, locate face guard breathing joint (1) and be arranged in adjusting face guard breathing joint (1) to respirator flow control device (3) of the velocity of flow of gas, its characterized in that: the flow adjusting device (3) comprises a joint inner sheet (4) arranged in a mask breathing joint (1), an adjusting sheet (5) rotatably connected to the joint inner sheet (4), a joint outer block (51) arranged outside the mask breathing joint (1), and an adjusting mechanism (52) arranged on the joint outer block (51) and controlling the adjusting sheet (5) to rotate relative to the joint inner sheet (4), wherein the adjusting sheet (5) and the joint inner sheet (4) are both provided with a plurality of air holes (53) in one-to-one correspondence, the adjusting mechanism (52) comprises an outer ring rack (54) fixedly connected to the circumferential outer wall of the adjusting sheet (5), an outer block inner gear (55) rotatably connected to the joint outer block (51) and meshed with the outer ring rack (54), and a knob (56) coaxially and fixedly connected to the outer block inner gear (55) and exposed out of the joint outer block (51), the joint outer block (51) is slidably connected with a limited rotating rubber block (57), the knob (56) is fixedly connected with a rubber block (58) tightly attached to the limited rotating rubber block (57), the joint outer block (51) is provided with a limited rotating rack (54), and two ends of the outer ring rotating block (54) are both pushing spring (54), and the outer ring rotating block (54) is connected with a limited rotating spring (59), the process of one rotation limiting sheet (42) from being attached to the outer internal gear (55) to being far away from the outer internal gear (55) corresponds to the process of communicating the air hole (53) of the adjusting sheet (5) and the air hole (53) of the joint inner sheet (4) from alignment to dislocation.

2. A noise reduction, damping, air supply apparatus for an air breathing mask as claimed in claim 1, wherein: the two end faces of the part, located in the joint outer block (51), of the adjusting sheet (5) are coaxially and fixedly connected with sealing rings (41), and the sealing rings (41) are tightly and coaxially connected to the joint outer block (51) in a rotating mode.

3. A noise reduction, damping, air supply apparatus for an air breathing mask as claimed in claim 1, wherein: the joint inner sheet (4) deviates from one side of one end of the air supply hose (2) communicated with the mask breathing joint (1), and a dislocation hole sheet (43) is arranged at the position, where the dislocation hole sheet (43) runs through a plurality of speed reducing holes (44) which are staggered with each air hole (53) of the joint inner sheet (4).

4. A noise reduction, damping, air supply apparatus for an air breathing mask as claimed in claim 3, wherein: the dislocation hole piece (43) is corresponding to the equal fixedly connected with round platform pipe (48) in the position department of each slow speed hole (44), and round platform pipe (48) are located dislocation hole piece (43) towards the side department of connecting inner sheet (4), and the internal diameter that round platform pipe (48) kept away from dislocation hole piece (43) one end is less than the internal diameter that round platform pipe (48) are close to dislocation hole piece (43) one end.

5. A noise reduction, damping, air supply apparatus for an air breathing mask as claimed in claim 1, wherein: connect inner leaf (4) to communicate one side department of face guard breathing joint (1) one end towards air feed hose (2) and be equipped with flow control damping blade (45), one end that air feed hose (2) are arranged in face guard breathing joint (1) is deviated from one side of connecting inner leaf (4) towards flow control damping blade (45).

6. A noise reduction, damping, air supply apparatus for an air breathing mask as claimed in claim 5, wherein: the utility model discloses a mask breathing joint, including face guard breathing joint (1), gas supply hose (2) are close to gas supply hose (2) one end and can dismantle and be connected with valve gap (46), and gas supply hose (2) are worn to establish and fixed connection in valve gap (46), and gas supply hose (2) are equipped with water conservancy diversion mouth (47) towards the one end of face guard breathing joint (1), and inside water conservancy diversion mouth (47) are located face guard breathing joint (1), and it has noise reduction damping filter screen (49) to press from both sides tightly between water conservancy diversion mouth (47) and the close terminal surface of gas supply hose (2).

7. A noise reducing, damping, air supply apparatus for an air breathing mask as claimed in claim 6, wherein: the inner wall of the mask breathing joint (1) is connected with a supporting block (36) in a sliding mode, the flow guide nozzle (47) is connected with the supporting block (36) in an abutting mode, and a supporting block spring (37) forcing the supporting block (36) to move towards one end, far away from the mask breathing joint (1), of the valve cover (46) is arranged inside the mask breathing joint (1).

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