Air masks for protection against radioactive contamination

Abstract

The invention discloses an air mask for radioactive contamination protection, which comprises: a support ring, on which an air inlet pipe is connected; and an outer cover shell, which is mounted on the support ring and encloses a cavity together with the support ring, and a mounting hole is provided on the top of the outer cover shell, in which an output air duct is connected, and a negative pressure fan and an exhaust fan are provided in the output air duct; wherein, when the negative pressure fan is started, the waste gas blown by the user is sucked into the output air duct and discharged through the exhaust fan, and oxygen enters the cavity from the air inlet pipe. Compared with the prior art, in the air mask for radioactive contamination protection of the present invention, when the negative pressure fan is started, the waste gas blown by the user is sucked into the output air duct and discharged through the exhaust fan, at this time, the air pressure in the cavity of the outer cover shell is reduced, and the oxygen outside the air mask for radioactive contamination protection enters the cavity of the outer cover shell through the air inlet pipe under the action of the air pressure difference, and the outer cover shell can realize negative pressure oxygen supply, which can improve the comfort, visual range and clarity of the air mask for radioactive contamination protection.

Description

Technical Field

[0001] The invention belongs to the field of radioactive pollution protection products, and more specifically, the invention relates to an air mask for radioactive pollution protection. Background Art

[0002] In nuclear facility workplaces, there are potential hazards such as radioactive surface contamination and air pollution. Frontline workers may inhale radioactive dust and aerosols if they are not careful, so it is particularly important for nuclear facility workers to wear appropriate and effective protective equipment.

[0003] In the related art, positive pressure protective hoods can provide protection far superior to that of ordinary masks and hoods. They can not only completely isolate workers from polluted environments, but also purify ambient air to provide clean flowing air inside, which has high safety and comfort. However, positive pressure protective hoods generally supply oxygen through positive pressure, which can easily lead to excessive pressure inside the hood, causing dizziness in the user; at the same time, there is a retention effect of the airflow inside the positive pressure protective hood, and the water vapor exhaled by the wearer is easy to gather at the hood window, causing fogging and affecting the user's field of vision. In addition, the positive pressure protective hood is supplied with compressed air, and the noise of the compressed air system is too loud. The sound pressure at the ear of the worker wearing the positive pressure protective hood is usually as high as 70-80dB (A), which causes long-term harm to the health of the worker.

[0004] In view of this, it is necessary to provide a safe and comfortable air mask for radioactive contamination protection. Summary of the invention

[0005] The purpose of the present invention is to overcome at least one defect of the prior art and provide a safe and comfortable air mask for radioactive contamination protection.

[0006] In order to achieve the above-mentioned object of the invention, the present invention provides an air mask for radioactive contamination protection, which comprises:

[0007] a support ring, to which an air inlet pipe is connected; and

[0008] An outer cover shell is mounted on the support ring and forms a cavity with the support ring. A mounting hole is provided on the top of the outer cover shell. An output air duct is connected to the mounting hole. A negative pressure fan and an exhaust fan are provided in the output air duct.

[0009] When the negative pressure fan is started, the exhaust gas blown by the user is sucked into the output air duct and discharged through the exhaust fan, and oxygen enters the cavity from the air inlet pipe.

[0010] According to one embodiment of the air mask for radioactive contamination protection of the present invention, a support rod is provided on the inner wall of the output air duct, and the exhaust fan is installed on the support rod and is located above the negative pressure fan.

[0011] According to an embodiment of the air mask for protection against radioactive contamination of the present invention, an input hole is provided on the support ring, and the air inlet pipe is fixedly installed in the input hole and communicated with the cavity.

[0012] According to one embodiment of the gas mask for protection against radioactive contamination of the present invention, four telescopic sliding shafts are installed on the top inner wall of the outer cover shell, each of the telescopic sliding shafts is slidably sleeved with a telescopic sleeve, and a force plate is fixedly installed at the bottom of each telescopic sleeve, and a buffer spring is slidably sleeved on the telescopic sliding shaft and the telescopic sleeve, one end of the buffer spring is in contact with the force plate, and the other end of the buffer spring is in contact with the top inner wall of the outer cover shell.

[0013] According to an embodiment of the gas mask for radioactive contamination protection of the present invention, two distance limiting sliding holes are provided on the inner wall of the telescopic sleeve, and the distance limiting sliding blocks are slidably installed in the two distance limiting sliding holes.

[0014] According to one embodiment of the air mask for protection against radioactive contamination of the present invention, an air intake block is provided on the inner wall of the support ring, a connecting hole is provided on the air intake block, the air intake pipe is fixedly installed in the connecting hole, a pressure reducing groove is provided on the inner wall surrounding the connecting hole, a vent is provided on the top of the pressure reducing groove, and the vent is connected to the cavity in the outer cover shell.

[0015] According to one embodiment of the air mask for radioactive contamination protection of the present invention, brackets are fixedly installed on the inner walls of both sides of the depressurization tank, rotating motors are fixedly installed on the two brackets, and the depressurization fan is fixedly sleeved on the output shaft of the rotating motor.

[0016] According to one embodiment of the gas mask for protection against radioactive contamination of the present invention, an active support block and a passive support block are installed at the bottom of the support ring, mounting slide bars are installed on both sides of the active support block and the passive support block, and an arc-shaped clamping plate is slidably sleeved on the mounting slide bar located on the same side.

[0017] According to one embodiment of the gas mask for protection against radioactive contamination of the present invention, the arc-shaped card plate is provided with a mounting slide hole, a sealing soft rubber pad is slidably installed in the mounting slide hole, a buffer slide hole is opened on the arc-shaped card plate, the mounting slide rod is slidably installed in the buffer slide hole, a buffer slot is opened on the inner wall of the buffer slide hole, a buffer card plate is slidably installed in the buffer slot, and the buffer card plate is fixedly installed on the mounting slide rod.

[0018] According to an embodiment of the gas mask for protection against radioactive contamination of the present invention, positioning slots are provided on both sides of the active support block, and a T-shaped slide groove connected to the T-shaped slide groove is provided on the active support block, a T-shaped slider is slidably installed in the T-shaped slide groove, and two racks are symmetrically fixedly installed on the bottom of the T-shaped slider, and two downward pressure springs are provided on the top inner wall of the T-shaped slide groove, and one end of the two downward pressure springs away from the top inner wall of the T-shaped slide groove is fixedly installed on the T-shaped slider.

[0019] Compared with the prior art, in the air mask for protection against radioactive contamination of the present invention, when the negative pressure fan is started, the exhaust gas blown by the user is sucked into the output air duct and discharged through the exhaust fan. At this time, the air pressure in the cavity of the outer cover shell is reduced, and the oxygen outside the air mask for protection against radioactive contamination enters the cavity of the outer cover shell through the air inlet pipe under the action of the air pressure difference. The outer cover shell can realize negative pressure oxygen supply, avoiding the excessive pressure caused by positive pressure oxygen supply, and improving the comfort of the air mask for protection against radioactive contamination; the gas exhaled by the user can be discharged in time and will not gather in the mask, avoiding the fogging of the window, and improving the user's field of vision and clarity. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] The following is a detailed description of the radioactive contamination protection gas mask and its technical effects in conjunction with the accompanying drawings and specific embodiments, wherein:

[0021] Figure 1 It is a schematic structural diagram of the air mask for radioactive contamination protection of the present invention.

[0022] Figure 2 The figure is a schematic diagram of the internal structure of the air mask for radioactive contamination protection of the present invention.

[0023] Figure 3 Another schematic diagram of the internal structure of the air mask for radioactive contamination protection of the present invention, wherein the outer cover shell has been removed.

[0024] Figure 4 It is a schematic structural diagram of the force-bearing plate in the air mask for protection against radioactive contamination of the present invention.

[0025] Figure 5 The figure is a schematic diagram of the partial structure of the support ring in the air mask for protection against radioactive contamination of the present invention.

[0026] Figure 6 This is a schematic structural diagram of the air intake block in the air mask for protection against radioactive contamination of the present invention.

[0027] Figure 7 The figure is a schematic diagram of the connection between the active support block and the arc-shaped clamping plate in the air mask for protection against radioactive contamination of the present invention.

[0028] Figure 8It is a schematic structural diagram of the active support block in the air mask for protection against radioactive contamination of the present invention.

[0029] Fig. 9 The figure is a schematic structural diagram of a T-shaped slider in an active support block in the gas mask for protection against radioactive contamination of the present invention.

[0030] Fig.10 for Fig. 9 An enlarged schematic diagram of the circled portion A is shown.

[0031] In the figure:

[0032] 1--Support ring; 2--Outer cover; 3--Mounting hole; 4--Output air duct; 5--Negative pressure fan; 6--Inner support rod; 7--Exhaust fan; 8--Input hole; 9--Intake pipe; 10--Intake block; 11--Connecting hole; 12--Pressure reduction groove; 13--Bracket; 14--Rotating motor; 15--Pressure reduction fan; 16--Ventilation hole; 17--Telescopic sliding shaft; 18--Telescopic sleeve; 19--Forced plate; 20--Buffer spring; 21--Limiting distance sliding hole; 22--Limiting distance slider; 23--Inner buffer arc ring; 24--Inner connecting shaft; 25-- External buffer arc ring; 26--external connecting shaft; 27--active support block; 28--driven support block; 29--installing slide rod; 30--arc-shaped card plate; 31--installing slide hole; 32--sealing soft rubber pad; 33--buffer card plate; 34--buffer slide hole; 35--buffer card slot; 36--limiting slide slot; 37--limiting slide shaft; 38--connecting slide block; 39--limiting baffle; 40--reset spring; 41--card block; 42--tooth groove; 43--T-type slide slot; 44--T-type slide block; 45--positioning card slot; 46--downward pressure spring; 47--rack. DETAILED DESCRIPTION

[0033] In order to make the invention purpose, technical solution and technical effect of the present invention clearer, the present invention is further described in detail below in conjunction with the accompanying drawings and specific implementation methods. It should be understood that the specific implementation methods described in this specification are only for explaining the present invention, not for limiting the present invention.

[0034] Please refer to Figure 1 and Figure 2 As shown, the radioactive contamination protection gas mask of the present invention comprises:

[0035] A support ring 1, to which an air inlet pipe 9 is connected; and

[0036] The outer cover shell 2 is mounted on the support ring 1 and forms a cavity (not marked) with the support ring 1. A mounting hole 3 is provided on the top of the outer cover shell 2. The mounting hole 3 is connected to an output air duct 4. A negative pressure fan 5 and an exhaust fan 7 are provided in the output air duct 4.

[0037] When the negative pressure fan 5 is started, the exhaust gas blown by the user is sucked into the output air duct 4 and discharged through the exhaust fan 7, and oxygen enters the cavity from the air inlet pipe 9.

[0038] Please refer to Figure 3 and Figure 4 As shown, four telescopic sliding shafts 17 are evenly fixedly installed on the top inner wall of the outer cover shell 2, and a telescopic sleeve 18 is slidably sleeved on each telescopic sliding shaft 17, and a force plate 19 is fixedly installed at the bottom of each telescopic sleeve 18. A buffer spring 20 is slidably sleeved on the telescopic sliding shaft 17 and the telescopic sleeve 18, and one end of the buffer spring 2 is in contact with the force plate 19, and the other end of the buffer spring 20 is in contact with the top inner wall of the outer cover shell 2. The buffer spring 20 can be used to support the force plate 19 so that the force plate 19 can be close to the user's head.

[0039] Two distance limiting sliding holes 21 are symmetrically provided on the inner wall of the telescopic sleeve 18, and a distance limiting slider 22 is slidably installed in each of the two distance limiting sliding holes 21, and the two distance limiting sliders 22 are fixedly installed on the same telescopic sliding shaft 17. The distance limiting sliding holes 21 and the distance limiting slider 22 interact with each other to prevent the telescopic sleeve 18 from falling off the telescopic sliding shaft 17, thereby ensuring the installation stability of the telescopic sleeve 18.

[0040] Three inner-tube support rods 6 are fixedly installed on the inner wall of the output air duct 4. The three inner-tube support rods 6 extend from the inner wall of the outer cover shell 2 toward the center of the output air duct 4. The exhaust fan 7 is installed at the intersection of the three inner-tube support rods 6. The three inner-tube support rods 6 can ensure the operating stability of the exhaust fan 7.

[0041] Please continue to refer to Figure 3 and Figure 4 As shown, the tops of the four force-bearing plates 19 are fixedly mounted with inner connecting shafts 24 and outer connecting shafts 26, and the same inner buffer arc ring 23 is slidably sleeved on two adjacent inner connecting shafts 24, and the same outer buffer arc ring 25 is slidably sleeved on two adjacent outer connecting shafts 26. The force stability of the four force-bearing plates 19 can be ensured by the interaction between the two inner buffer arc rings 23 and the inner connecting shafts 24, and the interaction between the two outer buffer arc rings 25 and the outer connecting shafts 26.

[0042] Please refer to Figure 2 , Figure 3 , Figures 5 to 7As shown, an input hole 8 is provided on the side wall of the support ring 1, and an air intake pipe 9 is fixedly sleeved in the input hole 8. The input hole 8 is used to ensure the installation stability of the air intake pipe 9. An air intake block 10 is fixedly installed on the inner wall of the support ring 1, and a connecting hole 11 is provided on the air intake block 10. The air intake pipe 9 passes through the input hole 8 and is fixedly installed on the inner wall of the connecting hole 11. A pressure reduction groove 12 is provided on the inner wall of the connecting hole 11, and a vent 16 is provided on the top inner wall of the pressure reduction groove 12. The vent 16 is connected to the cavity of the outer cover shell 2. Brackets 13 are fixedly installed on the inner walls of both sides of the pressure reduction groove 12 of the air intake block 10. The two brackets 13 are close to each other and fixedly installed with a rotating motor 14 at the intersection. The pressure reduction fan 15 is fixedly sleeved on the output shaft of the rotating motor 14. The bracket 13 can be used to support the rotating motor 14, thereby ensuring the stable operation of the pressure reduction fan 15.

[0043] Please refer to Figure 3 , Figure 5 , Figure 7 and Figure 8 As shown, an active support block 27 and a driven support block 28 are fixedly mounted on two opposite sides of the bottom of the support ring 1, and mounting slide bars 29 are fixedly mounted on both sides of the active support block 27 and the driven support block 28. An arc-shaped card plate 30 is slidably sleeved on the two mounting slide bars 29 on the same side. The arc-shaped card plate 30 is used to support the sealing soft rubber pad 32, which can stably cover the neck of the user, avoid the possibility of air leakage due to the negative pressure area in the head cover, and achieve the effect of sealing the head cover.

[0044] Please refer to Figures 7 to 10 As shown, the arc-shaped card plate 30 is provided with a mounting slide hole 31, in which a sealing soft rubber pad 32 is slidably installed, and the arc-shaped card plate 30 is provided with a buffer slide hole 34, in which the mounting slide bar 29 is slidably installed. A buffer card slot 35 is provided on the inner wall of the buffer slide hole 34, in which a buffer card plate 33 is slidably installed, and the buffer card plate 33 is fixedly installed on the mounting slide bar 29. The buffer slide hole 34 interacts with the mounting slide bar 29 to ensure the sliding stability of the arc-shaped card plate 30. The buffer card plate 33 and the buffer card slot 35 interact with each other to prevent the arc-shaped card plate 30 from falling off the mounting slide bar 29, thereby ensuring the installation stability of the arc-shaped card plate 30.

[0045] On both inner walls of the installation slide hole 31, there are limit slide grooves 36, and on one inner wall of each limit slide groove 36, there are limit slide shafts 37 fixedly installed, and on the limit slide shafts 37, there are limit baffles 39 fixedly installed. The limit slide shafts 37 are used to ensure the sliding stability of the connecting slider 38, and the limit baffles 39 are used to prevent the connecting slider 38 from falling off the limit slide shafts 37, thereby ensuring the installation stability of the connecting slider 38. The limit slide shafts 37 are slidably sleeved with the connecting slider 38, and the connecting slider 38 is fixedly installed on the sealing soft rubber pad 32. The limit slide shafts 37 are slidably sleeved with a return spring 40, one end of which is in contact with the limit baffle 39, and the other end of which is in contact with the connecting slider 38. Under the action of the return springs 40, the two connecting sliders 38 slide in the two limit slide grooves 36.

[0046] The arc-shaped clamping plate 30 is fixedly mounted with a clamping block 41 , on which a tooth groove 42 is provided, which meshes with a rack 47 , and a downward spring 46 is used to support the T-shaped slider 44 so that it can drive the rack 47 to be close to the tooth groove 42 , thereby ensuring the fixing stability of the arc-shaped clamping plate 30 .

[0047] Please refer to Figure 5 , Fig. 9 and Fig.10 As shown, the active support block 27 is provided with a T-shaped slide groove 43, in which a T-shaped slider 44 is slidably installed, and two racks 47 are symmetrically fixedly installed at the bottom of the T-shaped slider 44. The T-shaped slide groove 43 ensures the sliding stability of the T-shaped slider 44. When the user uses the hood, the two sealing soft rubber pads 32 need to be separated from each other first to display the support ring 1. The user can press the T-shaped slider 44 to slide the T-shaped slider 44 upward in the T-shaped slide groove 43 until the rack 47 on the T-shaped slider 44 is separated from the tooth groove 42, so that the block 41 in the positioning slot 45 can move, and the arc-shaped card plate 30 can slide on the mounting slide rod 29. At this time, the two arc-shaped clamping plates 30 are pulled away from each other, pushing the two sealing soft rubber pads 32 to unfold. After the user puts the head into the outer cover shell 2, the two arc-shaped clamping plates 30 are pushed to fit together until the clamping block 41 slides into the positioning clamping groove 45 and the tooth groove 42 and the rack 47 are engaged with each other, completing the fixation and locking of the two arc-shaped clamping plates 30.

[0048] Please refer to Fig.10As shown, two downward pressure springs 46 are fixedly installed on the top inner wall of the T-shaped slide 43, and one end of the two downward pressure springs 46 away from the top inner wall of the T-shaped slide 43 is fixedly installed on the T-shaped slider 44. Positioning slots 45 are provided on both sides of the active support block 27, and the positioning slots 45 are connected to the T-shaped slide 43. After the user puts the head into the outer cover shell 2, the two arc-shaped card plates 30 are pushed to fit each other until the card block 41 slides into the positioning slot 45 and the tooth groove 42 and the rack 47 are engaged with each other, completing the fixation and locking of the two arc-shaped card plates 30. Subsequently, under the action of the reset spring 40, the two connecting sliders 38 slide in the two limiting slide grooves 36, driving the sealing soft rubber pad 32 in the installation slide hole 31 to fit closely to the user's neck, thereby avoiding air leakage in the outer cover shell 2. The downward pressure spring 46 is used to support the T-shaped slider 44, so that it can drive the rack 47 to fit closely to the tooth groove 42, thereby ensuring the stability of the arc-shaped card plate 30.

[0049] The working principle of the air mask for radioactive contamination protection of the present invention is described in detail below in conjunction with the accompanying drawings:

[0050] When using the air mask for radioactive contamination protection of the present invention, the user turns on the negative pressure fan 5, sucks the waste gas blown by the user upward into the output air duct 4, and discharges it through the exhaust fan 7. The discharge of the waste gas causes the air pressure in the outer cover shell 2 to decrease, so the oxygen in the air intake pipe 9 is sent into the outer cover shell 2 under the action of the air pressure, completing the negative pressure oxygen supply of the outer cover shell 2. At this time, the oxygen input by the air intake pipe 9 first enters the connecting hole 11 of the air intake block 10, and then enters the pressure reduction groove 12. The rapid rotation of the pressure reduction fan 15 in the pressure reduction groove 12 quickly discharges the supplied oxygen upward, and directly outputs it to the user's facial area through the vent 16, and carries the waste gas exhaled by the user upward to the vicinity of the negative pressure fan 5, and enters the output air duct 4 upward under the action of the negative pressure fan 5.

[0051] During use, due to the support of the telescopic slide shaft 17, the telescopic sleeve 18 and the buffer spring 20 on the force-bearing plate 19, the force-bearing plate 19 can fit the user's head, so that the outer cover shell 2 will not be close to the user's skull, thereby preventing the air duct in the outer cover shell 2 from being blocked due to the user's head being too large, and thus preventing the exhaust gas from being discharged.

[0052] Combined with the above detailed description of the embodiment of the present invention, it can be seen that, compared with the prior art, in the air mask for protection against radioactive contamination of the present invention, through the combined action of the pressure reducing groove 12 and the pressure reducing fan 15, when the negative pressure fan 5 is started, the waste gas blown by the user is sucked into the output air duct 4 and discharged through the exhaust fan 7. At this time, the air pressure in the cavity of the outer cover shell 2 is reduced, and the air flow driven by the fan flows at the inlet of the air inlet pipe 9 to create a low-pressure area, which accelerates the oxygen supply speed of the air inlet pipe 9. The supplied oxygen is blown by the pressure reducing fan 15 and blown to the mouth and nose of the user through the vent 16. The oxygen outside the air mask for protection against radioactive contamination enters the cavity of the outer cover shell 2 through the air inlet pipe 9 under the action of the air pressure difference, and the negative pressure oxygen supply of the outer cover shell 2 can be realized. In addition, the waste gas exhaled by the user is blown upward and then guided out of the outer cover shell 2 through the negative pressure fan 5 and the exhaust fan 7, which can improve the comfort, visual range and clarity of the air mask for protection against radioactive contamination.

[0053] According to the above principles, the present invention can also make appropriate changes and modifications to the above embodiments. Therefore, the present invention is not limited to the specific embodiments disclosed and described above, and some modifications and changes to the present invention should also fall within the scope of protection of the claims of the present invention. In addition, although some specific terms are used in this specification, these terms are only for the convenience of description and do not constitute any limitation to the present invention.

Claims

1. An air mask for protection against radioactive contamination, characterized in that: include: A support ring, to which an air inlet pipe is connected; as well as An outer cover shell is mounted on the support ring and forms a cavity with the support ring. A mounting hole is provided on the top of the outer cover shell. An output air duct is connected to the mounting hole. A negative pressure fan and an exhaust fan are provided in the output air duct. When the negative pressure fan is started, the exhaust gas blown by the user is sucked into the output air duct and discharged through the exhaust fan, and oxygen enters the cavity from the air inlet pipe; An active support block and a driven support block are installed at the bottom of the support ring, and mounting slide bars are installed on both sides of the active support block and the driven support block, and an arc-shaped clamping plate is slidably sleeved on the mounting slide bars on the same side, and positioning grooves are opened on both sides of the active support block, and a T-shaped slide groove is provided on the active support block, and a T-shaped slider is slidably installed in the T-shaped slide groove, and two racks are symmetrically fixedly installed on the bottom of the T-shaped slider, and two downward pressure springs are provided on the top inner wall of the T-shaped slide groove, and one end of the two downward pressure springs away from the top inner wall of the T-shaped slide groove is fixedly installed on the T-shaped slider.

2. The radioactive contamination protection gas mask according to claim 1, characterized in that: A support rod is provided on the inner wall of the output air duct, and the exhaust fan is installed on the support rod and is located above the negative pressure fan.

3. The radioactive contamination protection gas mask according to claim 1, characterized in that: The support ring is provided with an input hole, and the air inlet pipe is fixedly installed in the input hole and communicated with the cavity.

4. The radioactive contamination protection air mask according to claim 1, characterized in that: Four telescopic sliding shafts are installed on the top inner wall of the outer cover shell, each of the telescopic sliding shafts is slidably sleeved with a telescopic sleeve, and a force plate is fixedly installed at the bottom of each telescopic sleeve. A buffer spring is slidably sleeved on the telescopic sliding shaft and the telescopic sleeve, one end of the buffer spring is in contact with the force plate, and the other end of the buffer spring is in contact with the top inner wall of the outer cover shell.

5. The radioactive contamination protection air mask according to claim 4, characterized in that: Two distance limiting sliding holes are arranged on the inner wall of the telescopic sleeve, and the distance limiting sliding blocks are slidably installed in the two distance limiting sliding holes.

6. The radioactive contamination protection gas mask according to claim 1, characterized in that: An air intake block is provided on the inner wall of the support ring, a connecting hole is provided on the air intake block, the air intake pipe is fixedly installed in the connecting hole, a pressure reducing groove is provided on the inner wall surrounding the connecting hole, a vent is provided on the top of the pressure reducing groove, and the vent is connected to the cavity in the outer cover shell.

7. The radioactive contamination protection air mask according to claim 6, characterized in that: Brackets are fixedly mounted on the inner walls of both sides of the pressure reducing groove, rotating motors are fixedly mounted on the two brackets, and the pressure reducing fan is fixedly sleeved on the output shaft of the rotating motor.

8. The radioactive contamination protection air mask according to claim 1, characterized in that: The arc-shaped card plate is provided with an installation slide hole, a sealing soft rubber pad is slidably installed in the installation slide hole, a buffer slide hole is opened on the arc-shaped card plate, the installation slide rod is slidably installed in the buffer slide hole, a buffer slot is opened on the inner wall of the buffer slide hole, a buffer card plate is slidably installed in the buffer slot, and the buffer card plate is fixedly installed on the installation slide rod.

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