CN115282312A

CN115282312A - Vehicle disinfection channel for epidemic prevention and control

Info

Publication number: CN115282312A
Application number: CN202210995629.9A
Authority: CN
Inventors: 黄宇琨; 杨靓; 王玮; 杨农; 魏欣; 黄泽炳; 易盼盼; 汤世玲; 顾慧敏
Original assignee: Xiangya Hospital of Central South University
Current assignee: Xiangya Hospital of Central South University
Priority date: 2022-08-18
Filing date: 2022-08-18
Publication date: 2022-11-04

Abstract

The invention relates to a vehicle disinfection channel for epidemic prevention and control, which comprises: the bottom plate, fixed mounting has the disinfection passageway that supplies the vehicle to pass through on the bottom plate, and the lateral wall all installs around the disinfection passageway and sprays the piece, and one side fixed mounting of disinfection passageway has the drive case, and the promotion subassembly that sprays the piece and remove about the drive is installed to the drive incasement, installs the confession liquid subassembly of being connected with spraying in the drive incasement. The second movable block that moves and the first movable block that moves drive the promotion frame of connecting and move down, and when the threaded rod counter-rotation, rotatory threaded rod promotes second movable block and the first movable block rebound on it of threaded connection, the promotion frame reciprocates, the fixed pipe of the promotion frame drive connection that moves up and down, through reciprocating of fixed pipe, two promotion frame rebound when having large vehicle to pass through, and two promotion frame rebound when having small-size vehicle, make the shower nozzle of installation on two upper and lower fixed pipes be close to the top and the chassis of vehicle, carry out abundant disinfection to the vehicle.

Description

Vehicle disinfection channel for epidemic prevention and control

Technical Field

The invention relates to the field of epidemic situation prevention and control, in particular to a vehicle disinfection channel for epidemic situation prevention and control.

Background

Common vehicle disinfection passageway disinfection shower nozzle is fixed, can't remove, and the vehicle type that need disinfect is different, and some small-size vehicles's chassis and height are all lower, and some large vehicle's chassis and height are all than higher in addition, and the measurement of two kinds of different grade types is when disinfecting, and two upper and lower shower nozzles can't be close to the automobile body, and the antiseptic solution that leads to spraying is blown off by wind very easily for the vehicle can't carry out comprehensive disinfection.

Disclosure of Invention

The invention aims to provide a vehicle disinfection channel for epidemic prevention and control, which aims to solve the problems in the background technology.

In order to achieve the purpose, the invention provides the following technical scheme:

a vehicle disinfection lane for epidemic prevention and control comprising:

the vehicle disinfection device comprises a bottom plate, a disinfection channel for a vehicle to pass through is fixedly installed on the bottom plate, jetting pieces are installed on the peripheral side walls of the disinfection channel, a driving box is fixedly installed on one side of the disinfection channel, a pushing assembly for driving the upper jetting piece and the lower jetting piece to move is installed in the driving box, and a liquid supply assembly connected with the jetting pieces is installed in the driving box;

a driving assembly connected with the pushing assembly and the liquid supply assembly is arranged in the driving box, the driving assembly drives the pushing assembly and the liquid supply assembly to operate, an on-off part is arranged at the joint of the driving assembly and the pushing assembly, and the driving assembly is controlled to be connected with the pushing assembly through the on-off part;

the infrared transmitter used for transmitting infrared rays is fixedly mounted on the bottom plate, the infrared receiver arranged opposite to the infrared transmitter is fixedly mounted on the bottom plate, and the number of the infrared rays received by the infrared receiver controls the on-off part and the driving assembly.

As a further scheme of the invention: the injection member comprises a fixed pipe, a plurality of uniformly-arranged spray heads are fixedly mounted on the fixed pipe, the fixed pipes on two sides are fixedly mounted on the inner wall of the disinfection channel, the length of the upper fixed pipe and the length of the lower fixed pipe are smaller than that of the fixed pipes on two sides, and the fixed pipes on two sides are fixedly mounted with connecting pipes connected with the upper fixed pipe.

As a still further scheme of the invention: the promotion subassembly includes the catch bar of fixed mounting on two upper and lower fixed pipes, and one side that the disinfection passageway was kept away from to the catch bar runs through disinfection passageway and fixed mounting has the propelling movement frame, and the gliding recess of confession below propelling movement frame has been seted up to the bottom plate.

As a still further scheme of the invention: the driving box is rotatably connected with a threaded rod, two sections of external threads with different thread pitches are arranged on the threaded rod, the external threads on the lower portion are connected with a first moving block fixedly installed with the pushing frame on the lower portion in a threaded mode, and the external threads on the upper portion are connected with a second moving block fixedly installed with the pushing frame on the upper portion in a threaded mode.

As a still further scheme of the invention: the liquid supply assembly comprises two piston cylinders which are symmetrically arranged in the drive box, one side of each piston cylinder is fixedly arranged and extends to a liquid outlet pipe outside the drive box, one end of each piston cylinder and a plurality of piston rods are fixedly arranged and are far away from the liquid outlet pipe, one side of each drive box is fixedly arranged with a liquid storage box, a liquid suction pipe extending into the liquid storage box is fixedly arranged on each piston cylinder, one check valve is fixedly arranged on each liquid suction pipe and one check valve is fixedly arranged on each liquid outlet pipe, and the two check valves are opposite in direction.

As a still further scheme of the invention: the drive box is rotatably connected with a rocker, the piston cylinder is slidably connected with a piston block, one side of the piston block is fixedly provided with a piston rod extending out of the piston cylinder, one side of the piston rod far away from the piston block is fixedly provided with a hinged seat, and the hinged seat is hinged with a push-pull rod rotatably connected with the rocker.

As a still further scheme of the invention: the drive assembly comprises a servo motor fixedly installed in the drive box, the servo motor is fixedly installed with a support frame supporting the servo motor, the support frame is fixedly installed on the drive box, a rotating shaft on one side of the rocker is fixedly installed with a ratchet wheel, and a disc fixedly installed with a rotating shaft of the servo motor is rotatably connected to the ratchet wheel.

As a still further scheme of the invention: the side wall fixed mounting all around of ratchet has the ratchet of evenly setting, rotates on the disc to be connected with the cowl with the ratchet joint, and fixed mounting has the cowl who carries on spacingly to the pawl on the disc.

As a still further scheme of the invention: the on-off part is including setting up two first bevel gears that set up relatively in the drive box, one of them first bevel gear and servo motor's pivot fixed mounting, one side pivot of threaded rod extend to the drive box in and with another first bevel gear fixed mounting, fixed mounting has the drum in the drive box, fixed mounting has the electro-magnet in the drum, sliding connection has the slide bar in the drum, the slide bar extends to outside the drum and fixed mounting has the second bevel gear with the first bevel gear meshing of both sides, the butt has the cover to establish the compression spring on the slide bar between second bevel gear and the drive box inner wall.

Compared with the prior art, the invention has the beneficial effects that: the invention has novel design, when the threaded rod rotates in the positive direction, the rotating threaded rod pushes the second moving block connected with the threaded rod to move downwards, and simultaneously, the first moving block connected with the threaded rod in a threaded manner moves downwards, the second moving block and the first moving block drive the connected pushing frame to move downwards, when the threaded rod rotates in the reverse direction, the rotating threaded rod pushes the second moving block and the first moving block connected with the threaded rod in a threaded manner to move upwards, the pushing frame moves upwards and downwards, the moving pushing frame drives the connected fixed tubes to move upwards and downwards, through the up-and-down movement of the fixed tubes, when a large-sized vehicle passes through, the two pushing frames move upwards, and when a small-sized vehicle passes through, the two pushing frames move downwards, so that the spray heads arranged on the upper fixed tube and the lower fixed tube are close to the top and the chassis of the vehicle, and the vehicle is sufficiently disinfected.

Drawings

Fig. 1 is a schematic perspective view of an embodiment of a vehicle disinfection passage for epidemic situation prevention and control.

FIG. 2 is an enlarged schematic view of a push frame in an embodiment of a disinfection tunnel for an epidemic prevention and control vehicle.

FIG. 3 is a schematic view showing the internal structure of a drive box in an embodiment of a vehicle disinfection passage for epidemic prevention and control.

Fig. 4 is an enlarged schematic view of a liquid suction pipe in an embodiment of a disinfection passage for an epidemic prevention and control vehicle.

Fig. 5 is an enlarged structural schematic diagram of a servo motor in an embodiment of a vehicle disinfection channel for epidemic situation prevention and control.

FIG. 6 is a schematic view showing the internal structure of a cylinder in an embodiment of a disinfection passage for a vehicle for controlling an epidemic situation.

FIG. 7 is a schematic view showing the internal structure of a ratchet wheel in an embodiment of the disinfection passage for an epidemic prevention and control vehicle.

In the figure: 1. a base plate; 2. a disinfection channel; 3. an infrared emitter; 4. an infrared receiver; 5. a fixed tube; 6. a spray head; 7. a pushing frame; 8. a push rod; 9. a connecting pipe; 10. a liquid storage tank; 11. a drive box; 12. a piston cylinder; 13. a liquid outlet pipe; 14. a liquid pumping pipe; 15. a piston rod; 16. a hinged seat; 17. A push-pull rod; 18. a rocker; 19. a servo motor; 20. a support frame; 21. a ratchet wheel; 22. a first bevel gear; 23. a second bevel gear; 24. a compression spring; 25. a one-way valve; 26. a threaded rod; 27. a first moving block; 28. a second moving block; 29. a cylinder; 30. a slide bar; 31. an electromagnet; 32. a disc; 33. an arc-shaped baffle plate; 34. a pawl.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious 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.

In addition, an element described herein as being "secured to" or "disposed on" another element may be directly on the other element or intervening elements may also be present. When an element is referred to as being "connected" to another element, it can be directly connected to the other element or intervening elements may also be present. The terms "vertical," "horizontal," "left," "right," and the like as used herein are for illustrative purposes only and do not represent the only embodiments.

Referring to fig. 1 and 2, in an embodiment of the present invention, a vehicle disinfection passage for epidemic prevention and control includes:

the bottom plate 1, fixed mounting has the disinfection passageway 2 that supplies the vehicle to pass through on the bottom plate 1, the lateral wall all installs the piece that sprays all around of disinfection passageway 2.

The injection member is including fixed pipe 5, fixed pipe 5 is gone up fixed mounting and is had a plurality of align to grid's shower nozzle 6, both sides fixed pipe 5 equal fixed mounting be in on 2 inner walls of disinfection passageway, two from top to bottom fixed pipe 5's length is less than both sides fixed pipe 5's length, both sides fixed pipe 5 fixed mounting have with the upper end fixed pipe 5 connects connecting pipe 9.

The antiseptic solution that sets up passes through in the pipeline gets into fixed pipe 5, and installs a plurality of shower nozzles on fixed pipe 5, and the antiseptic solution that gets into in the fixed pipe 5 passes through a plurality of shower nozzles blowout, makes the spray regime of antiseptic solution more even, because the width of vehicle roughly keeps unanimous, so the fixed pipe 5 of both sides keeps fixed, because the difference in height of vehicle leads to two fixed pipes 5 about needing to adjust.

One side of disinfection passageway 2 is fixed mounting has drive case 11, install in the drive case 11 and drive about the drive the injection piece carry out the promotion subassembly that removes.

Referring to fig. 1 and 2, the pushing assembly includes a pushing rod 8 fixedly mounted on the upper and lower fixing tubes 5, one side of the pushing rod 8 far away from the disinfection channel 2 penetrates through the disinfection channel 2 and is fixedly mounted with a pushing frame 7, and the bottom plate 1 is provided with a groove for the pushing frame 7 to slide below.

Concretely, promotion frame 7 reciprocates, and the fixed pipe 5 that the promotion frame 7 that removes drives the connection reciprocates, through reciprocating of fixed pipe 5, two promotion frames 7 rebound when oversize vehicle passes through, and two promotion frames 7 rebound when the minibus, make the shower nozzle of installation on two upper and lower fixed pipes 5 be close to the top and the chassis of vehicle, carry out abundant disinfection to the vehicle.

Referring to fig. 1 and 3, a threaded rod 26 is rotatably connected to the driving box 11, two sections of external threads with different thread pitches are formed on the threaded rod 26, a first moving block 27 fixedly mounted on the lower pushing frame 7 is connected to the lower external thread through a threaded joint, and a second moving block 28 fixedly mounted on the upper pushing frame 7 is connected to the upper external thread through a threaded joint.

In detail, when the threaded rod 26 rotates in the forward direction, the rotating threaded rod 26 pushes the second moving block 28 screwed thereto to move downward, and simultaneously, the first moving block 27 screwed thereto also moves downward, the moving second moving block 28 and the first moving block 27 drive the connected pushing frame 7 to move downward, and when the threaded rod 26 rotates in the reverse direction, the rotating threaded rod 26 pushes the second moving block 28 screwed thereto and the first moving block 27 to move upward, of course, the thread pitch of the external thread of the threaded connection of the first moving block 27 is smaller, and the thread pitch of the external thread of the threaded connection of the second moving block 28 is larger, so that the distance moved by the first moving block 27 is smaller than the distance moved by the second moving block 28 when the threaded rod 26 rotates for the same number of turns.

And a liquid supply assembly connected with the injection piece is arranged in the driving box 11.

Referring to fig. 3 and 4, the liquid supply assembly includes two piston cylinders 12 symmetrically installed in the driving box 11, a liquid outlet pipe 13 extending to the outside of the driving box 11 is fixedly installed at one side of each piston cylinder 12, one end of the liquid outlet pipe 13 far away from the piston cylinder 12 is fixedly installed with a plurality of piston rods 15, a liquid storage box 10 is fixedly installed at one side of the driving box 11, a liquid pumping pipe 14 extending to the inside of the liquid storage box 10 is fixedly installed on the piston cylinder 12, check valves 25 are fixedly installed on both the liquid pumping pipe 14 and the liquid outlet pipe 13, and the directions of the two check valves 25 are opposite.

The piston cylinder 12 is arranged to pump out a large amount of disinfectant from the liquid storage tank 10 through the liquid pumping pipe 14, because the one-way valve 25 is arranged, the liquid pumping pipe 14 can only pump out the liquid, the liquid entering the piston cylinder 12 enters the plurality of fixed pipes 5 through the liquid outlet pipe 13, and of course, because the one-way valve 25 is arranged, the liquid outlet pipe 13 can only discharge the liquid.

Referring to fig. 3, a rocker 18 is rotatably connected in the driving box 11, a piston block is slidably connected in the piston cylinder 12, a piston rod 15 extending out of the piston cylinder 12 is fixedly installed at one side of the piston block, a hinge seat 16 is fixedly installed at one side of the piston rod 15 far away from the piston block, and a push-pull rod 17 rotatably connected with the rocker 18 is hinged on the hinge seat 16.

Specifically, the rocker 18 rotates, the rotating rocker 18 drives the push-pull rod 17 which is rotatably connected to the rocker 18 to swing back and forth, the moving push-pull rod 17 drives the hinged seat 16 to move back and forth, and the moving hinged seat 16 drives the piston block in the piston cylinder 12 to move back and forth to suck liquid, so that the piston cylinder 12 can continuously spray disinfectant because the two piston cylinders 12 are fixedly arranged.

And a driving assembly connected with the pushing assembly and the liquid supply assembly is arranged in the driving box 11, and the pushing assembly and the liquid supply assembly are driven to operate by the driving assembly.

Referring to fig. 3 and 5, the driving assembly includes a servo motor 19 fixedly installed in the driving box 11, the servo motor 19 is fixedly installed with a supporting frame 20 for supporting the servo motor, the supporting frame 20 is fixedly installed on the driving box 11, a rotating shaft at one side of the rocker 18 is fixedly installed with a ratchet 21, and the ratchet 21 is rotatably connected with a disc 32 fixedly installed with the rotating shaft of the servo motor 19.

In detail, the servo motor 19 operates, the output shaft of the rotating servo motor 19 drives the lower disc 32 to rotate, the rotating disc 32 drives the connected ratchet wheel 21 to rotate, and the servo motor 19 is supported by the fixed support frame 20, so that the servo motor 19 operates more stably.

Referring to fig. 7, the circumferential side wall of the ratchet wheel 21 is fixedly provided with uniformly arranged ratchets, the disc 32 is rotatably connected with an arc-shaped baffle 33 clamped with the ratchets, and the disc 32 is fixedly provided with an arc-shaped baffle 33 for limiting the pawl 34.

The output shaft of the servo motor 19 is arranged to drive the connected disc 32 to rotate, the rotating disc 32 drives the pawl 34 which is rotatably connected to the rotating disc to rotate around the central shaft, when the disc 32 rotates in the forward direction, the pawl 34 is clamped with the ratchet arranged on the ratchet wheel 21, so that the disc 32 can drive the ratchet wheel 21 to rotate, and when the disc 32 rotates in the reverse direction, the pawl 34 and the ratchet arranged on the ratchet wheel 21 are staggered, so that the disc 32 cannot drive the ratchet wheel 21 to rotate.

Fixed mounting has the infra-red transmitter 3 that is used for the transmission infrared ray on the bottom plate 1, fixed mounting has on the bottom plate 1 with the relative infrared receiver 4 that sets up of infra-red transmitter 3, through the quantity that infrared receiver 4 received the infrared ray is right on-off and drive assembly control.

Specifically, the infrared transmitter 3 generates a plurality of infrared rays having different heights to one side, and the measured height is determined by the amount of the infrared rays received by the infrared receiver 4.

Referring to fig. 3, 5 and 6, the on-off member includes two first bevel gears 22 disposed in the driving box 11, one of the first bevel gears 22 is fixedly mounted to a rotating shaft of the servo motor 19, a rotating shaft on one side of the threaded rod 26 extends into the driving box 11 and is fixedly mounted to the other first bevel gear 22, a cylinder 29 is fixedly mounted in the driving box 11, an electromagnet 31 is fixedly mounted in the cylinder 29, a sliding rod 30 is slidably connected in the cylinder 29, the sliding rod 30 extends out of the cylinder 29 and is fixedly mounted with second bevel gears 23 engaged with the first bevel gears 22 on two sides, and a compression spring 24 sleeved on the sliding rod 30 is abutted between the second bevel gear 23 and the inner wall of the driving box 11.

The arranged electromagnet 31 attracts the sliding rod 30 below, the attracted sliding rod 30 moves upwards, the moving sliding rod 30 drives the connected second bevel gear 23 to move upwards, the first bevel gear 22 on one side cannot be driven to rotate when rotating, the abutted compression spring 24 is extruded at the same time, and when the electromagnet 31 is powered off, the compressed compression spring 24 pushes the abutted second bevel gear 23 to move downwards, so that the second bevel gear 23 is meshed with the two first bevel gears 22 below.

It will be evident to those skilled in the art that the invention is not limited to the details of the foregoing illustrative embodiments, and that the present invention may be embodied in other specific forms without departing from the spirit or essential attributes thereof. The present embodiments are therefore to be considered in all respects as illustrative and not restrictive, the scope of the invention being indicated by the appended claims rather than by the foregoing description, and all changes which come within the meaning and range of equivalency of the claims are therefore intended to be embraced therein. Any reference sign in a claim should not be construed as limiting the claim concerned.

Furthermore, it should be understood that although the present specification describes embodiments, not every embodiment includes only a single embodiment, and such description is for clarity purposes only, and it is to be understood that all embodiments may be combined as appropriate by one of ordinary skill in the art to form other embodiments as will be apparent to those of skill in the art from the description herein.

Claims

1. The utility model provides a vehicle disinfection passageway is used in epidemic situation prevention and control which characterized in that includes:

the vehicle disinfection device comprises a bottom plate (1), wherein a disinfection channel (2) for a vehicle to pass through is fixedly installed on the bottom plate (1), jetting parts are installed on the peripheral side walls of the disinfection channel (2), a driving box (11) is fixedly installed on one side of the disinfection channel (2), a pushing assembly for driving the jetting parts to move up and down is installed in the driving box (11), and a liquid supply assembly connected with the jetting parts is installed in the driving box (11);

a driving assembly connected with the pushing assembly and the liquid supply assembly is installed in the driving box (11), the driving assembly drives the pushing assembly and the liquid supply assembly to operate, an on-off piece is installed at the connection position of the driving assembly and the pushing assembly, and the driving assembly is controlled to be connected with the pushing assembly through the on-off piece;

fixed mounting has infrared transmitter (3) that are used for transmitting infrared on bottom plate (1), fixed mounting has on bottom plate (1) with infrared receiver (4) that infrared transmitter (3) set up relatively, through infrared receiver (4) receive infrared quantity right break-make spare and drive assembly control.

2. The vehicle disinfection channel for epidemic prevention and control according to claim 1, wherein said injection member comprises a fixed pipe (5), said fixed pipe (5) is provided with a plurality of uniformly arranged spray heads (6), two sides of said fixed pipe (5) are fixedly arranged on the inner wall of said disinfection channel (2), two sides of said fixed pipe (5) are smaller than two sides of said fixed pipe (5) and said fixed pipe (5) is fixedly arranged with an upper end of said fixed pipe (5) connecting pipe (9).

3. The vehicle disinfection channel for epidemic prevention and control according to claim 1, wherein the pushing assembly comprises pushing rods (8) fixedly mounted on the upper and lower fixing pipes (5), one side of each pushing rod (8) far away from the disinfection channel (2) penetrates through the disinfection channel (2) and is fixedly mounted with a pushing frame (7), and a groove for the pushing frame (7) to slide below is formed in the bottom plate (1).

4. The vehicle disinfection channel for epidemic prevention and control according to claim 3, wherein the driving box (11) is rotatably connected with a threaded rod (26), the threaded rod (26) is provided with two sections of external threads with different pitches, the external threads on the lower part are in threaded connection with a first moving block (27) fixedly mounted with the lower pushing frame (7), and the external threads on the upper part are in threaded connection with a second moving block (28) fixedly mounted with the upper pushing frame (7).

5. The vehicle disinfection channel for epidemic prevention and control of claim 1, characterized in that, the confession liquid subassembly includes fixed mounting in two symmetrical piston cylinder (12) that set up in drive case (11), one side fixed mounting of piston cylinder (12) extends to drain pipe (13) outside drive case (11), drain pipe (13) are kept away from the one end and a plurality of piston cylinder (12) piston rod (15) fixed mounting, one side fixed mounting of drive case (11) has liquid reserve tank (10), fixed mounting is gone up in piston cylinder (12) has the extension to liquid suction pipe (14) in liquid reserve tank (10), liquid suction pipe (14) with equal fixed mounting has check valve (25) on drain pipe (13), and two check valve (25) opposite direction.

6. The vehicle disinfection channel for epidemic prevention and control according to claim 5, wherein a rocker (18) is rotationally connected in the drive box (11), a piston block is slidably connected in the piston cylinder (12), a piston rod (15) extending out of the piston cylinder (12) is fixedly mounted on one side of the piston block, an articulated seat (16) is fixedly mounted on one side of the piston rod (15) far away from the piston block, and a push-pull rod (17) rotatably connected with the rocker (18) is hinged on the articulated seat (16).

7. The vehicle disinfection channel for epidemic prevention and control of claim 1, wherein the drive assembly comprises a servo motor (19) fixedly mounted in the drive box (11), the servo motor (19) is fixedly mounted with a support frame (20) supporting the servo motor, the support frame (20) is fixedly mounted on the drive box (11), a ratchet wheel (21) is fixedly mounted on one side of a rotating shaft of the rocker (18), and a disc (32) fixedly mounted on the rotating shaft of the servo motor (19) is rotatably connected to the ratchet wheel (21).

8. The vehicle disinfection channel for epidemic prevention and control according to claim 7, wherein the side walls around the ratchet wheel (21) are fixedly provided with evenly arranged ratchets, the disc (32) is rotatably connected with an arc-shaped baffle (33) clamped with the ratchets, and the disc (32) is fixedly provided with an arc-shaped baffle (33) for limiting the pawl (34).

9. The epidemic prevention and control vehicle disinfection channel according to claim 1, wherein the on-off member comprises two first bevel gears (22) arranged in the drive box (11) in an opposite manner, one of the first bevel gears (22) is fixedly mounted with a rotating shaft of the servo motor (19), a rotating shaft on one side of the threaded rod (26) extends into the drive box (11) and is fixedly mounted with the other first bevel gear (22), a cylinder (29) is fixedly mounted in the drive box (11), an electromagnet (31) is fixedly mounted in the cylinder (29), a sliding rod (30) is slidably connected in the cylinder (29), the sliding rod (30) extends out of the cylinder (29) and is fixedly mounted with a second bevel gear (23) meshed with the first bevel gears (22) on two sides, and a compression spring (24) sleeved on the sliding rod (30) is abutted between the second bevel gear (23) and the inner wall of the drive box (11).