CN210008776U

CN210008776U - Handrail folding structure

Info

Publication number: CN210008776U
Application number: CN201920266032.4U
Authority: CN
Inventors: 单志进
Original assignee: Xiamen Haubei Children's Products Co Ltd
Current assignee: Xiamen Haubei Children's Products Co Ltd
Priority date: 2019-03-01
Filing date: 2019-03-01
Publication date: 2020-02-04
Anticipated expiration: 2029-03-01

Abstract

The utility model discloses a handrail folding structure relates to crib technical field, and its technical scheme main points are: including the stand riser, with the handrail group of the union coupling of standing and set up the aggregate unit on handrail group, aggregate unit passes through the haulage rope control, the pipe top of standing is provided with the wire winding pole, the one end of haulage rope is connected on aggregate unit, fixedly connected with fixed block behind the wire winding pole is walked around to the other end, the pipe of standing is close to one side of handrail pipe and articulates and is provided with the traction block, the spacing groove has been seted up to the traction block bottom, the haulage rope penetrates the spacing inslot, and the fixed block is spacing in the spacing groove, the one end that the traction block kept away from the stand riser is connected with control traction block. The traction rope can be pulled to untie the linkage device by driving the traction block to swing through the pushing device, the traction stroke of the traction rope is reduced, the whole structure is simple, the traction rope is prevented from being blocked when being pulled, and the handrail folding device has the advantage of improving the convenience of bending and folding the handrail.

Description

Handrail folding structure

Technical Field

The utility model relates to a crib technical field, more specifically say that it relates to a handrail is closed and is closed structure.

Background

The crib is the indispensable special furniture in the family that possess the baby, and the purpose is for making the baby can possess more comfortable safe sleep and activity environment. For the convenience of the crib storage and transportation in the prior art, the crib frame is folded and folded by adopting a fast folding direction.

If the granted publication number is CN208064926U, the publication date is 2018.11.09, which discloses a quickly foldable crib frame, comprising an insertion tube, an unlocking device disposed on the insertion tube, a support tube disposed perpendicular to the end of the insertion tube, a first linkage device disposed at the connection between the support tube and the insertion tube, a long handrail set connected with the support tube, a short handrail set perpendicular to the long handrail set, and a second linkage device disposed on the long handrail set and the short handrail set, wherein the insertion tube is further provided with a locking mechanism connected with the unlocking device in a matching manner, the locking mechanism is connected with the unlocking device in a matching manner, the first linkage device comprises a linkage frame, a first top block disposed at the end of the folding tube, and a second top block disposed in the support tube, a gap is left between the first top block and the second top block, and the first top block and the second top block are both disposed in the linkage frame, the joint of the first jacking block and the folding pipe is also provided with a positioning column, the first jacking block is also connected with a second spring, one end of the second spring props against the positioning column, the other end of the second spring props against the inner wall of the first jacking block, the second jacking block is connected with a traction rope, the traction rope is also provided with a branching block which divides the traction rope into a long section which is matched and connected with the long handrail group and a short section which is matched and connected with the short handrail group, the linkage frame is also internally provided with an inner inserting hole which is matched and connected with the pipe supporting piece, one end of the balance pipe, far away from the connecting clamping frame, is matched and hinged with the interior of the linkage frame, the second linkage device comprises a movable frame arranged on the long handrail group, a connecting cylinder arranged in the movable frame, a third spring arranged in the connecting cylinder and a limiting piece matched and arranged with one end of the connecting cylinder, far away from the movable frame, and a limiting shaft matched and connected with the long handrail group is arranged in the connecting cylinder, the third spring props against the limiting shaft, the limiting part is connected with the movable frame in a matched mode, and the connecting cylinder is connected with the traction rope in a matched mode.

The pipe inserting piece is retracted by controlling the unlocking device, the second linkage device is pulled by the traction rope in the retracting process, and the second linkage device is unlocked, so that the long handrail group or the short handrail group is bent in half, and the bending of the handrail group is realized. But the monolithic union coupling length overlength of haulage rope, the haulage rope receives the in-process that the intubate piece was pull, need just can drive the second linkage after the linkage of multichannel stroke, leads to the traction process of haulage rope to receive the jamming easily, influences the handrail and bends the convenience of closing.

SUMMERY OF THE UTILITY MODEL

To current technical problem, an object of the utility model is to provide a handrail is received and is closed structure reduces the linkage stroke of haulage rope, prevents to receive to close the time jamming, has the advantage that improves the convenience that the handrail was bent.

In order to achieve the above purpose, the utility model provides a following technical scheme:

the utility model provides a handrail folding structure, includes the stand pipe, with the handrail group of standing union coupling and set up the aggregate unit on handrail group, aggregate unit passes through the haulage rope control, stand pipe top is provided with the wire winding pole, the one end of haulage rope is connected on aggregate unit, and fixedly connected with fixed block behind the wire winding pole is walked around to the other end, the pipe of standing is close to one side of handrail pipe and articulates and is provided with the traction block, the spacing groove has been seted up to the traction block bottom, the haulage rope penetrates the spacing inslot, just the fixed block is spacing in the spacing inslot, the one end that the stand pipe was kept away from to the traction block is connected with control traction block pivoted thrust unit.

So set up, drive the traction block through thrust unit and rotate on the pipe of standing for thrust unit pull-down's in-process drives the traction block and swings downwards, and under the effect that the fixed block is spacing in the spacing inslot, the traction block can drive the fixed block and move down, thereby stimulates the haulage rope, makes the haulage rope drive aggregate unit untie, thereby makes the handrail group can bend to receive and close convenient and fast. The winding rod is convenient for guide the traction rope to pull, and traction stagnation is avoided. Through even being on the traction block with the haulage rope, drive the haulage rope by thrust unit and stimulate, reduce the stroke of pulling of haulage rope, overall structure is simple, receives the jamming when preventing that the haulage rope from pulling, has the advantage that improves the convenience that the handrail was bent.

Further setting: the pushing device comprises a connecting rod which axially slides along the standing pipe, a pushing block fixed at the top of the connecting rod and a swinging block hinged on the pushing block, a sliding groove is formed in the side wall of the standing pipe along the axial direction of the standing pipe, the connecting rod and the pushing block both lift and slide on the sliding groove, and one end, far away from the pushing block, of the swinging block is hinged on one end, far away from the standing pipe, of the traction block.

So set up, through control connecting rod lapse for the connecting rod drives and promotes the piece and slide on the sliding tray, thereby drives swing piece and moves down, moves down by swing piece and drives the traction block and rotate, thereby realizes the effect of pulling haulage rope, and simple structure simple operation improves the convenience that the handrail was bent.

Further setting: the limiting piece is arranged at the notch of the sliding groove and fixed on the stand pipe, the guide groove is formed in the surface, close to the sliding groove, of the limiting piece, and the connecting rod penetrates through the guide groove in a sliding mode.

So set up, through the spacing piece that sets up for the connecting rod slides and wears to locate the guide way in, thereby the stable lift of guide connecting rod slides, so that stably pull the haulage rope, improve the stability of closing.

Further setting: the armrest group comprises armrest tubes which are symmetrically connected with both sides of the linkage device, one end of each armrest tube is hinged on the station vertical tube, the linkage device comprises a connecting block hinged with one end of the handrail tube far away from the station vertical tube, a positioning block fixed in the connecting block, a travel limiting block fixed in the handrail tube, a sliding block sliding in one end of the handrail tube close to the positioning block and a return spring arranged between the travel limiting block and the sliding block, a travel path for the sliding block to slide is formed between the limiting block and the positioning block, one side of the positioning block close to the sliding block is provided with a positioning groove corresponding to the side wall of the sliding block, two ends of the reset spring are respectively connected to the limiting block and the sliding block, when the reset spring is not stressed, the side wall of the sliding block is inserted into the positioning groove to form limiting, one end of the traction rope, far away from the pushing device, penetrates through the limiting block in a sliding mode and is fixedly connected to the sliding block.

So set up, when the handrail was received, the haulage rope pulling sliding block was to being close to the slip of restriction piece direction for outside the sliding block broke away from the constant head tank of locating piece, thereby make the handrail pipe around the pin joint downswing of station riser, thereby make the handrail pipe that is located the connecting block both sides receive and close convenient and fast. Receive the extrusion at the gliding in-process reset spring of sliding block and produce elasticity, when launching handrail group, the lateral wall of sliding block is to being located constant head tank department to in the lateral wall that drives the sliding block by reset spring's elasticity inserts the constant head tank, realize the handrail pipe effect of being located on the connecting block, the handrail of being convenient for launches, improves the convenience of operation.

Further setting: the limiting device is characterized in that a guide block is fixed on one side, close to the sliding block, of the limiting block, an insertion groove is formed in one side, close to the limiting block, of the sliding block, the insertion groove is correspondingly inserted into the guide block, the reset spring is sleeved on the guide block, and two ends of the reset spring are respectively connected to the bottom of the insertion groove and one side, close to the insertion groove, of the limiting block.

Through the arrangement, the guide block is inserted into the insertion groove in the process that the sliding block slides to the limiting block through the guide block and the insertion groove, so that the sliding guide of the sliding block is provided, the sliding block can accurately move conveniently, and the convenience for folding and folding the handrail is improved; the reset spring is sleeved on the guide block, so that the reset spring can be guided to deform, the reset spring is prevented from being bent, and the service life of the reset spring is ensured.

Further setting: the constant head tank is inwards sunken to form by the locating piece, just the constant head tank is provided with the inclined plane from the outside slope of constant head tank groove bottom to the top, the sliding block is close to the side of constant head tank and is provided with the shape of carving, the inclined plane sets up with carving the shape corresponding.

So set up, the sliding block inserts the constant head tank in the back, and the cooperation is formed on the inclined plane to wedge face laminating, receives the pulling back of haulage rope at the sliding block, and the sliding block lateral wall breaks away from the in-process of constant head tank, and the inclined plane is stable with wedge face cooperation guide sliding block and is break away from the constant head tank, improves the convenience that the lateral wall of sliding block breaks away from the constant head tank to the handrail is folded and is closed.

Further setting: the handrail tube bottom has seted up the hole of sliding along its axial direction on, the sliding block bottom is provided with guide bolt, guide bolt wear to establish the hole of sliding and with sliding block threaded connection, guide bolt slides in the hole of sliding along the axial direction of handrail tube.

So set up, through the hole that slides of seting up for the guide bolt slides in the hole that slides on being fixed in the sliding block back, thereby makes the gliding in-process of sliding block, by guide bolt and the cooperation direction in the hole that slides, improves the gliding accuracy and the stability of sliding block, so that the handrail is closed and is closed.

Further setting: the sliding hole is a waist-shaped long hole, and the length of the waist-shaped long hole is consistent with the sliding stroke distance of the sliding block.

So set up, waist shape slot hole can cooperate with guide bolt, and the length of waist shape slot hole provides the space for guide bolt's slip to be convenient for guide bolt slides at the downthehole slip, and gliding in-process receives the restriction of waist shape slot hole length, has restricted guide bolt's slip stroke, and the accurate guide sliding block of being convenient for slides to suitable position.

By adopting the technical scheme, the utility model discloses relative prior art compares, has following advantage:

1. the traction rope can be pulled to unlock the linkage device by driving the traction block to swing through the pushing device, the traction stroke of the traction rope is reduced, the whole structure is simple, the traction rope is prevented from being blocked during traction, and the handrail folding device has the advantage of improving the convenience of bending and folding the handrail;

2. the lifting sliding fit of the connecting rod and the pushing block is utilized to drive the swinging block to swing downwards, so that the traction block can be driven to swing downwards, the traction rope is pulled, and the convenience of bending and folding the handrail is improved;

3. through the cooperation of sliding block, restriction piece, reset spring and locating piece, when the haulage rope received the pulling, the sliding block breaks away from the constant head tank of locating piece, can the down swing handrail pipe, and the handrail of being convenient for is bent and is received and close.

Drawings

Fig. 1 is a schematic view of an inner structure of the armrest folding structure;

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

FIG. 3 is an enlarged schematic view at B of FIG. 1;

FIG. 4 is a schematic view of the connection of the bottom of the linkage to the crib insert.

In the figure: 1. a standing pipe; 11. a sliding groove; 2. a handrail group; 21. a handrail tube; 211. a sliding hole; 3. a linkage device; 31. connecting blocks; 32. positioning blocks; 321. positioning a groove; 3211. an inclined surface; 33. a line limiting block; 331. a guide block; 34. a slider; 341. inserting grooves; 342. a wedge-shaped surface; 35. a return spring; 4. a hauling rope; 5. a wire winding rod; 6. a fixed block; 7. a traction block; 71. a limiting groove; 8. a pushing device; 81. a connecting rod; 82. a pushing block; 83. a swing block; 84. a swing lever; 9. a limiting sheet; 91. a guide groove; 10. and (4) guiding the bolt.

Detailed Description

The folding structure of the armrest will be further described with reference to fig. 1 to 4.

A handrail folding structure is shown in figure 1 and comprises a standing pipe 1, a handrail group 2 connected with the standing pipe 1 and a linkage device 3 arranged on the handrail group 2, wherein the linkage device 3 is controlled by a traction rope 4, the linkage device 3 can be unlocked by pulling the traction rope 4, and the handrail group 2 is folded.

As shown in fig. 1 and 2, the handrail group 2 includes handrail tubes 21 symmetrically connected to two sides of the linkage device 3, one ends of the two handrail tubes 21 are respectively hinged to two sides of the linkage device 3, and the other ends are respectively hinged to the two station vertical tubes 1, when the linkage device 3 is unlocked, the two handrail tubes 21 can be folded down around a hinged point with the station vertical tube 1, so as to fold the handrail. Specifically, the linkage device 3 includes a connecting block 31 hinged to one end of the handrail tube 21 away from the station vertical tube 1, a positioning block 32 fixed in the connecting block 31, a limit block 33 fixed in the handrail tube 21, a sliding block 34 sliding in one end of the handrail tube 21 close to the positioning block 32, and a return spring 35 disposed between the limit block 33 and the sliding block 34. A stroke path for sliding the sliding block 34 is formed between the limiting block 33 and the positioning block 32, a positioning groove 321 corresponding to the side wall of the sliding block 34 is arranged on one side of the positioning block 32 close to the sliding block 34, two ends of a return spring 35 are respectively connected to the limiting block 33 and the sliding block 34, when the return spring 35 is not stressed, the side wall of the sliding block 34 is inserted into the positioning groove 321 to form limiting, and one end of the traction rope 4 penetrates through the limiting block 33 in a sliding mode and is fixedly connected to the sliding block 34. When the traction rope 4 is pulled, the sliding block 34 slides towards the direction close to the limiting block 33, at the moment, the reset spring 35 is extruded to generate elastic force, the side wall of the sliding block 34 is separated from the positioning groove 321 after the sliding block 34 slides, so that the limiting effect of the positioning groove 321 is released, the handrail tube 21 can be swung downwards, and the handrail tube 21 can be conveniently folded; when the handrail tube 21 is unfolded, the side wall of the sliding block 34 is opposite to the positioning groove 321, and the elastic force of the return spring 35 drives the side wall of the sliding block 34 to be inserted into the positioning groove 321, so that the positioning limitation of the sliding block 34 is realized, the handrail tube 21 is positioned on the connecting block 31, the unfolding positioning of the handrail is completed, and the handrail is very convenient and fast.

As shown in fig. 2, further, a guide block 331 is fixed on one side of the row limiting block 33 close to the sliding block 34, an insertion groove 341 is formed on one side of the sliding block 34 close to the row limiting block 33, the insertion groove 341 and the guide block 331 are correspondingly inserted, the return spring 35 is sleeved on the guide block 331, and two ends of the return spring 35 are respectively connected to the bottom of the insertion groove 341 and one side of the row limiting block 33 close to the insertion groove 341, so as to guide the sliding block 34 to slide and guide the return spring 35 to deform, thereby improving convenience of starting and unlocking the linkage device 3. The hole 211 that slides has been seted up along its axial direction in handrail pipe 21 bottom, sliding block 34 bottom is provided with guide bolt 10, guide bolt 10 wears to establish the hole 211 that slides and with sliding block 34 threaded connection, guide bolt 10 slides in the hole 211 that slides along handrail pipe 21's axial direction, the hole 211 that slides sets up to waist shape slot hole, and the length size of waist shape slot hole is unanimous with sliding block 34 sliding stroke distance size, thereby slide by guide bolt 10 in the hole 211 that slides and form the direction, so that guide sliding block 34 slides accurately.

As shown in fig. 2, in order to improve the convenience of inserting the positioning groove 321 and the side wall of the sliding block 34, the positioning groove 321 is formed by inward recessing the positioning block 32, an inclined surface 3211 is obliquely arranged from the bottom to the top of the positioning groove 321, a wedge surface 342 is arranged on the side surface of the sliding block 34 close to the positioning groove 321, and the inclined surface 3211 and the wedge surface 342 are arranged correspondingly, so that the side wall of the sliding block 34 slides out of the positioning groove 321 or is inserted into the positioning groove 321, and the convenience of folding or unfolding the armrest is.

As shown in fig. 1 and 3, a winding rod 5 is fixedly arranged in the top of the standing pipe 1, one side of the standing pipe 1 close to the handrail pipe 21 is hinged with a traction block 7, the bottom of the traction block 7 is provided with a limit groove 71, and the traction rope 4 penetrates into the limit groove 71. The end, far away from the linkage device 3, of the traction rope 4 is fixedly connected with the fixing block 6 after bypassing the winding rod 5, the fixing block 6 is limited in the limiting groove 71, the traction rope 4 can be pulled by pulling the traction block 7 to swing downwards, and therefore the linkage device 3 is controlled to be untied. And a pushing device 8 for controlling the traction block 7 to rotate is connected to one end of the traction block 7 far away from the station riser 1. The traction block 7 is driven to swing downwards through the pushing device 8, the traction rope 4 can be pulled, the traction stroke of the traction rope 4 is shortened, the winding rod 5 forms guiding, the clamping stagnation of the folding is avoided, and the convenience of the handrail folding is improved.

As shown in fig. 1 and 3, specifically, the pushing device 8 includes a connecting rod 81 that slides axially along the standing pipe 1, a pushing block 82 fixed to the top of the connecting rod 81, and a swinging block 83 hinged to the pushing block 82, a sliding groove 11 is formed in the side wall of the standing pipe 1 along the axial direction of the standing pipe, the connecting rod 81 and the pushing block 82 both slide on the sliding groove 11, and one end of the swinging block 83, which is far away from the pushing block 82, is hinged to one end of the traction block 7, which is far away from the standing pipe 1. In order to improve the gliding stability of connecting rod 81, the notch department of sliding tray 11 is provided with spacing piece 9, and spacing piece 9 is fixed in on the stand pipe 1 of standing, and spacing piece 9 has seted up guide way 91 near sliding tray 11 on the surface, and connecting rod 81 slides and wears to establish the setting of guide way 91 to guide connecting rod 81 to slide, be convenient for drive promotion piece 82 descends, thereby be convenient for spur haulage rope 4. Referring to fig. 4, the bottom of the connecting rod 81 is hinged to a swing rod 84, one end of the swing rod 84, which is far away from the connecting rod 81, is hinged to the insertion tube of the crib, and after the unlocking device of the crib is unlocked, the insertion tube is driven to rotate in the standing tube 1, the swing rod 84 can be driven to swing upwards around the hinge point at the bottom of the connecting rod 81, so that the connecting rod 81 is driven to descend, the pushing block 82 is driven to descend, the pulling rope 4 is pulled to unlock the linkage device 3, and the folding and unfolding of the handrail are facilitated.

The working principle is as follows: in the process of sliding downwards through the connecting rod 81, the pushing block 82 is driven to descend, so that the swinging block 83 is driven to swing downwards, the swinging block 83 drives the traction block 7 to swing downwards, and the traction rope 4 is pulled. In-process that haulage rope 4 stimulates drives sliding block 34 and removes to the direction that is close to limit piece 33, until the lateral wall and the constant head tank 321 separation of sliding block 34, handrail pipe 21 does not receive the restriction of constant head tank 321 this moment, can be round the pin joint downswing with stand pipe 1 to receive handrail pipe 21. The in-process of whole linkage reduces the stroke of haulage rope 4, adopts the guide of connecting rod 81 to 4 pulling of haulage rope, overall structure is simple, receives the jamming when preventing haulage rope 4 from pulling, has the advantage that improves the convenience that the handrail was bent and was closed.

It is above only the utility model discloses a preferred embodiment, the utility model discloses a scope of protection does not only confine above-mentioned embodiment, the all belongs to the utility model discloses a technical scheme under the thinking all belongs to the utility model discloses a scope of protection. It should be noted that, for those skilled in the art, various modifications and decorations can be made without departing from the principle of the present invention, and these modifications and decorations should also be regarded as the protection scope of the present invention.

Claims

1. The utility model provides a handrail folding structure, includes stand riser (1), handrail group (2) and the aggregate unit (3) that set up on handrail group (2) of being connected with stand riser (1), aggregate unit (3) are through haulage rope (4) control, its characterized in that: station riser (1) top is provided with wire winding pole (5), the one end of haulage rope (4) is connected on aggregate unit (3), and fixed connection has fixed block (6) behind wire winding pole (5) is walked around to the other end, one side that station riser (1) is close to handrail tube (21) is articulated to be provided with traction block (7), spacing groove (71) have been seted up to traction block (7) bottom, haulage rope (4) penetrate in spacing groove (71), just fixed block (6) are spacing in spacing groove (71), the one end that stand riser (1) was kept away from in traction block (7) is connected with control traction block (7) pivoted thrust unit (8).

2. The handrail folding structure of claim 1, wherein: thrust unit (8) including along station riser (1) axial slip's connecting rod (81), be fixed in promotion piece (82) at connecting rod (81) top and articulate swing piece (83) on promoting piece (82), sliding tray (11) have been seted up along its axial direction on the lateral wall of station riser (1), connecting rod (81) and promotion piece (82) all go up and down to slide on sliding tray (11), swing piece (83) keep away from the one end that promotes piece (82) articulate in one of traction block (7) and keep away from station riser (1) and serve.

3. The handrail folding structure of claim 2, wherein: the notch department of sliding tray (11) is provided with spacing piece (9), spacing piece (9) are fixed in on stand pipe (1), guide way (91) have been seted up on spacing piece (9) are close to sliding tray (11) on the surface, connecting rod (81) slide and wear to establish guide way (91) setting.

4. The handrail folding structure of claim 1, wherein: the handrail group (2) comprises handrail tubes (21) symmetrically connected to two sides of a linkage device (3), one ends of the handrail tubes (21) are hinged to the station vertical tube (1), the linkage device (3) comprises a connecting block (31) hinged to one end, far away from the station vertical tube (1), of the handrail tubes (21), a positioning block (32) fixed in the connecting block (31), a limit block (33) fixed in the handrail tubes (21), a sliding block (34) sliding in one end, close to the positioning block (32), of the handrail tubes (21) and a return spring (35) arranged between the limit block (33) and the sliding block (34), a stroke path for the sliding block (34) is formed between the limit block (33) and the positioning block (32), and a positioning groove (321) corresponding to the side wall of the sliding block (34) is arranged on one side, close to the sliding block (34), of the positioning block (32), the two ends of the reset spring (35) are respectively connected to the line limiting block (33) and the sliding block (34), when the reset spring (35) is not stressed, the side wall of the sliding block (34) is inserted into the positioning groove (321) to form limiting, and one end, far away from the pushing device (8), of the traction rope (4) slides to penetrate through the line limiting block (33) and is fixedly connected to the sliding block (34).

5. The handrail folding structure of claim 4, wherein: the sliding block (33) is fixed with a guide block (331) on one side close to the sliding block (34), an insertion groove (341) is formed in one side of the sliding block (34) close to the sliding block (33), the insertion groove (341) and the guide block (331) are correspondingly inserted, the return spring (35) is sleeved on the guide block (331), and two ends of the return spring (35) are respectively connected to the bottom of the insertion groove (341) and one side of the sliding block (33) close to the insertion groove (341).

6. The handrail folding structure of claim 4, wherein: the positioning groove (321) is formed by inwards recessing the positioning block (32), the positioning groove (321) is provided with an inclined surface (3211) from the bottom of the positioning groove (321) to the top in an inclined manner, the side surface of the sliding block (34) close to the positioning groove (321) is provided with a wedge-shaped surface (342), and the inclined surface (3211) and the wedge-shaped surface (342) are correspondingly arranged.

7. The handrail folding structure of claim 4, wherein: the handrail tube (21) bottom has seted up hole (211) that slides on its axial direction, sliding block (34) bottom is provided with guide bolt (10), guide bolt (10) wear to establish hole (211) that slides and with sliding block (34) threaded connection, guide bolt (10) slide in hole (211) that slides along the axial direction of handrail tube (21).

8. The handrail folding structure of claim 7, wherein: the sliding hole (211) is a waist-shaped long hole, and the length of the waist-shaped long hole is consistent with the sliding stroke distance of the sliding block (34).