CN213269520U

CN213269520U - Sliding door device

Info

Publication number: CN213269520U
Application number: CN202020699556.5U
Authority: CN
Inventors: 钟玉波
Original assignee: Riyuefeng Xiamen Automation Equipment Co Ltd
Current assignee: Riyuefeng Xiamen Automation Equipment Co Ltd
Priority date: 2020-04-30
Filing date: 2020-04-30
Publication date: 2021-05-25
Anticipated expiration: 2030-04-30

Abstract

The utility model discloses a door moving device, which comprises a door body, a frame body and a pulley assembly, wherein the door body slides through a first slide rail hung on the frame body by the pulley assembly; the pulley assembly is arranged between the pulley assembly and the frame body; the door opening and closing assembly comprises a first swing rod, a second swing rod, a first elastic body, a second sliding rail, a connecting piece and a movable block; the first swing rod and the second swing rod are hinged through a rotating shaft and are arranged in the frame body, and the first swing rod and the second swing rod are arranged at a certain angle; the first elastic body is arranged between the second sliding rail and the second swing rod, one end of the first elastic body is fixed on the frame body, and the other end of the first elastic body acts on the bottom of the second swing rod, so that the second swing rod and the second sliding rail form a distance for the moving part to penetrate through; the utility model provides a move a device reaches the automatic effect of closing the door that current electrodynamic type moved the door through mechanical type device, effectively solves the big defect of the continuous operating force of the current mechanical type translation door body simultaneously.

Description

Sliding door device

Technical Field

The utility model relates to a move a manufacturing field, concretely relates to move a device.

Background

At present, movable doors (sliding doors) are widely used, such as shower rooms in shopping malls and residences; the existing sliding door structure is divided into two types, one is an electric sliding door used in various large business super and office places, and the other is a mechanical manual translation door body structure; although the two methods are widely used, the two methods have many defects:

electric sliding door: (1) the sliding door device mainly comprises a motor matched with a transmission structure to drive the movable door to move horizontally, a power supply and a controller are required to be connected, the door is difficult to open in case of power failure, and professional personnel are required to handle the door; (2) the structure is excessively complex, the cost is high, and professional staff is required for assembly during installation; (3) the internal conducting wire moves continuously along with the sliding door, and the electric leakage danger is easy to occur after long-time use; (4) the application range is small, the shower room or the room door in a living room cannot be applied, and the installation of the shower room or the room door needs a large space, so the shower room or the room door is difficult to be applied to living;

and the mechanical manual translation door body structure: (1) the door moving mode needs a large operating force to drive and does not have an automatic opening and closing function; the door handle is required to be pulled back manually and reversely to close the door, so that the door body is closed reversely, the door opening and closing operation is required twice, and the door body is required to be driven to move by using two opposite acting forces, so that the use experience is poor; (2) the door opening and closing distance is limited, namely the hand of a user needs to pull the door body to be larger than the body width, and the hand of the user needs to be moved to a corresponding position, so that the use is very inconvenient; (3) when a plurality of people pass in and out simultaneously, the door body needs to be opened and closed continuously by each person, and the practicability is poor;

in summary, a sliding door device is needed to meet the requirement of use.

SUMMERY OF THE UTILITY MODEL

An object of the utility model is to overcome the above-mentioned defect or problem that exist among the background art, provide a move a device, its simple structure, preparation are simple and convenient and easy to be realized, reach the automatic effect of closing the door that current electrodynamic type moved the door through the mechanical type device, effectively solve the big defect of the continuous operating force of the current mechanical type translation door body simultaneously.

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

a door moving device comprises a door body, a frame body and a pulley assembly, wherein the door body slides through a first sliding rail hung on the frame body through the pulley assembly; the method is characterized in that: the pulley assembly is arranged between the pulley assembly and the frame body; the door opening and closing assembly comprises a first swing rod, a second swing rod, a first elastic body, a second sliding rail, a connecting piece and a movable block;

the first swing rod and the second swing rod are hinged through a rotating shaft and are arranged in the frame body, and the first swing rod and the second swing rod are arranged at a certain angle; the other end of the first swing rod is abutted against the second slide rail;

the first elastic body is arranged between the second sliding rail and the second swing rod, one end of the first elastic body is fixed on the frame body, and the other end of the first elastic body acts on the bottom of the second swing rod, so that the second swing rod and the second sliding rail form a distance for the moving part to penetrate through;

the second sliding rail is arranged in the frame body and is parallel to the first sliding rail; the second sliding rail is provided with an inclined surface which extends upwards in an inclined manner along the door opening direction;

the connecting piece is connected with the pulley assembly; the connecting piece is provided with a guide part which is vertical to the first track, and the guide part is used for the movable block to penetrate and slide;

the door body is driven to open the door, the connecting piece connected with the door body moves along with the door body, the upper movable block moves upwards along the first swing rod and moves towards the second swing rod after crossing the rotating shaft, and the movable block acts on the second swing rod and the inclined plane of the second slide rail to move through self weight and/or external loading force so as to link the door body to automatically move.

Further, the gravity of the movable block is greater than the acting force of the first elastic body.

Furthermore, the device also comprises a loading piece which is arranged in the frame body; the loading piece acts on the movable block to enable the movable block to sequentially and circularly displace on the first swing rod, the second swing rod and the second slide rail.

Furthermore, the loading part comprises a coil spring and a first traction rope, the pulley assembly at the inner end of the coil spring is fixedly connected, and the outer end of the coil spring is connected with the lower surface of the movable block through the traction rope; when the pulley assembly moves towards the door opening direction along the first sliding rail, the inner end of the coil spring is driven to wind tightly continuously, and meanwhile, the traction rope pulls the movable block to press and slide along the first swing rod and the second swing rod; when the pulley assembly moves towards the door closing direction along the second sliding rail, the pulley assembly rotates reversely, so that the outer end of the coil spring rotates reversely.

Furthermore, the loading piece is a first spring, the first spring is sleeved on the guide part on the connecting piece, one end of the first spring acts on the inner top surface of the frame body, and the other end of the first spring is supported on the upper end of the movable block.

Furthermore, the loading piece comprises a second spring and a second traction rope, the second spring is arranged in parallel to the first slide rail, one end of the second spring is fixed on the side part of the frame body, and the other end of the second spring is connected with the second traction rope; the other end of the second traction rope is fixed with the lower surface of the movable block.

Furthermore, a limiting groove is further formed in the first sliding rail and/or the second sliding rail, and the limiting groove is used for limiting the roller and/or the movable block of the pulley assembly.

Furthermore, the pulley component comprises a first pulley block and a second pulley block which are sequentially arranged on the door body at intervals towards the door opening direction; the first pulley block and the second pulley block respectively comprise a first roller, a second roller, a first roller seat and a second roller seat, and the first roller and the second roller are respectively arranged on the first roller seat and the second roller seat; the switch door assembly is arranged on the second roller seat.

Furthermore, the device also comprises a buffer piece which is arranged on the first roller seat; the buffer piece comprises a shell, a push rod and a second elastic body, wherein the second elastic body and the push rod are arranged on the shell, and two ends of the second elastic body respectively act on the inner wall of the shell and one end of the push rod; the buffer piece moves reversely along with the pulley assembly to drive the other end of the pushing rod to be abutted against the side wall of the frame body.

As can be seen from the above description of the present invention, compared with the prior art, the present invention has the following advantages:

the utility model provides a door moving device, its simple structure, preparation are simple and convenient and easy to realize, realize two functions simultaneously through mechanical type switch door subassembly, first utilize first pendulum rod and movable block cooperation in the process of opening the door, realize that only need user apply less effort, and manual application force door opening distance is little, can realize opening the door, need not to pull very big distance to the direction of opening the door with the hand, can realize the effect of whole journey opening; meanwhile, the door body does not need to be pulled to close by applying force again, and is automatically closed through the second sliding rail, so that the effect of electric sliding door is realized; more importantly, the structure of this scheme is extremely simple, the part is few, adopts optimal overall arrangement, so the user also can assemble by oneself, more is applicable to the electricity merchant and sells, need not professional and professional instrument and realizes the assembly, and application scope is wider, has integrated the mechanical type and has moved the advantage that the door and the electrodynamic type moved the door, and it is very convenient to use.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings required to be used in the description of the embodiments are briefly introduced below, and it is obvious that the drawings in the following description are some embodiments of the present invention, and it is obvious for those skilled in the art to obtain other drawings without creative efforts.

Fig. 1 is a schematic perspective exploded view of a sliding door device according to an embodiment of the present invention;

fig. 2 is a first schematic plan view of the door moving device according to the first embodiment of the present invention, taken along the door opening direction;

fig. 3 is a schematic plan view of the first door moving device according to the first embodiment of the present invention, illustrating the second door moving device in the door opening direction;

fig. 4 is a first schematic plan view of the door moving device according to the first embodiment of the present invention, illustrating the door closing direction;

fig. 5 is a schematic plan view of the first door moving device according to the second embodiment of the present invention, illustrating the second door moving device in the door closing direction;

fig. 6 is a first schematic plan view of the door moving device according to the second embodiment of the present invention, taken along the door opening direction;

fig. 7 is a second schematic plan view of the door moving device according to the second embodiment of the present invention, taken along the door opening direction;

fig. 8 is a first schematic plan view of the door moving device according to the second embodiment of the present invention, illustrating the door closing direction;

fig. 9 is a first schematic plan view of the door moving device according to the third embodiment of the present invention, taken along the door opening direction;

fig. 10 is a schematic plan view of the door moving device according to the third embodiment of the present invention, illustrating the second direction;

fig. 11 is a first schematic plan view of the door moving device according to the third embodiment of the present invention, illustrating the door closing direction;

fig. 12 is a second schematic plan view of the door moving device according to the third embodiment of the present invention, taken along the door closing direction;

fig. 13 is a first schematic plan view of the door moving device according to the fourth embodiment of the present invention.

Detailed Description

The technical solution in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. It is obvious that the described embodiments are preferred embodiments of the invention and should not be considered as excluding other embodiments. Based on the embodiment of the present invention, all other embodiments obtained by a person of ordinary skill in the art without creative work belong to the protection scope of the present invention.

In the claims, the specification and the drawings, unless otherwise expressly limited, the terms "first," "second," or "third," etc. are used for distinguishing between different elements and not for describing a particular sequence.

In the claims, the specification and the drawings, unless otherwise expressly limited, to the extent that directional terms such as "center", "lateral", "longitudinal", "horizontal", "vertical", "top", "bottom", "inner", "outer", "upper", "lower", "front", "rear", "left", "right", "clockwise", "counterclockwise" and the like are used, the positional or orientational relationships illustrated in the drawings are based on the positional and orientational relationships illustrated in the drawings and are merely for convenience of describing the present invention and simplifying the description, but do not indicate or imply that the device or element so referred to must have a particular orientation or be constructed and operated in a particular orientation, and therefore should not be construed as limiting the scope of the present invention in any way.

In the claims, the description and the drawings of the present application, unless otherwise expressly limited, the term "fixedly connected" or "fixedly connected" is used, which is to be understood broadly, that is, any connection mode without displacement relation or relative rotation relation between the two, that is, including non-detachably fixed connection, integrated connection and fixed connection through other devices or elements.

In the claims, the specification and the drawings, the terms "including", "comprising" and variations thereof, if used, are intended to be inclusive and not limiting.

Referring to fig. 1 to 5, a sliding door apparatus is mainly used for various buildings, such as kitchen doors, shower doors, balcony partition doors, etc., in shopping malls, office buildings, and residential buildings; the sliding door device of the utility model not only has simple structure and convenient use, but also solves the defects of the prior mechanical sliding door body, and has the advantages of an electric sliding door structure, and 4 embodiments are listed for specific description;

embodiment one, referring to fig. 1 to 5,

the utility model uses the sliding door device in shower room, which comprises a door body 1, a frame body 2 and a pulley component 3,

the door body 1 is hung on a first sliding rail 20 on the frame body 2 through the pulley assembly 3 to slide;

the frame body 2 comprises an upper frame body, a lower frame body, a left frame body and a right frame body 21, 22, 23 and 24, of course, only the upper frame body and the lower frame body 21 and 22 can be used, and the left frame body and the right frame body 23 and 24 are bathroom wall bodies;

the pulley component 3 comprises a first pulley block 31 and a second pulley block 32 which are sequentially arranged on the door body 1 at intervals towards the door opening direction; the first and second pulley blocks 31 and 32 respectively comprise a first and

second roller

310 and 320 and a first and second roller seat 311 and 321, and the first and

second rollers

310 and 320 are respectively arranged on the first and second roller seats 311 and 321; wherein, the first and

second rollers

310 and 320 are suspended to slide in the first slide rail 20; the door opening and closing assembly 4 is arranged on the second roller seat 321;

the door opening and closing assembly 4 comprises a first swing rod 41, a second swing rod 42, a first elastic body 43, a second slide rail 44, a connecting piece 45 and a movable block 46;

the first and

second swing rods

41, 42 are hinged by a rotating shaft 47, the rotating shaft 47 is perpendicular to the side wall of the frame body 2, and the other ends of the first and

second swing rods

41, 42 are free ends, so that the first and

second swing rods

41, 42 hang downward to make the first and

second swing rods

41, 42 arranged at a certain angle; here at an angle preferably greater than 120 °;

a first elastic body 43, which is disposed between the second slide rail 44 and the second swing link 42, and one end of which is fixed to the frame body 2, and the other end of which acts on the bottom of the second swing link 42, so that the second swing link 42 and the second slide rail 44 form a space for the movable member to pass through; it should be noted that, in the embodiment, the first elastic body 43 is exemplified by a torsion spring, one end of the torsion spring 43 is fixed on the side wall of the frame body 2, and the other end of the torsion spring 43 is supported against the lower surface of the second swing link 42, so that a channel 48 for the movable block 46 to pass through is formed between the lower surface of the second swing link 42 and the second slide rail 44 through the support of the torsion spring 43;

a second slide rail 44, which is provided in the frame body 2 and is arranged in parallel with the first slide rail 20, wherein the parallel arrangement may be parallel arrangement on the same horizontal plane or parallel arrangement with spatial dislocation; one surface of the second slide rail 44 facing the second swing link 42 has an inclined surface 440, and the inclined surface 440 extends obliquely upward along the door opening direction; it should be noted that the second slide rail 44 can be assembled only by being locked on the side wall of the frame body 2 by screws;

a connecting member 45 connected to the second roller seat 321 of the pulley assembly 3; the connecting member 45 has a guide portion 450 perpendicular to the first rail 20, and the guide portion 450 is penetrated and slid by the movable block 46;

a loading member 6 provided in the frame body 2; the loading member 6 acts on the movable block 46 to make the movable block 46 sequentially and circularly displace on the first and

second swing rods

41 and 42 and the second slide rail 44; the loading part 6 comprises a coil spring 61 and a first traction rope 62, the pulley assembly 3 at the inner end of the coil spring 61 is fixedly connected, and the outer end of the coil spring 61 is connected with the lower surface of the movable block 46 through the traction rope;

the door body 1 is driven to open, the connecting piece 45 connected with the door body moves along with the door body, the upper movable block 46 moves upwards along the first swing rod 41 and moves towards the second swing rod 42 by crossing the rotating shaft 47, and the movable block 46 moves under the action of self weight and/or external loading force on the second swing rod 42 and the inclined surface 440 of the second slide rail 44 so as to be linked with the automatic opening and closing of the door body 1;

when the door is actually used, a user holds the handle on the door body 1 with a hand and moves towards the door opening direction, and it should be noted that the distance that the user only needs to apply force to pull is the sliding distance of the movable block 46 on the first swing rod 41; specifically, when the door body 1 is pulled to displace, the first and

second rollers

310 and 320 slide along the first slide rail 20 (here, the first and

second rollers

310 and 320 always slide on the first slide rail 20); the connecting member 45 of the door body 1 assembly connected to the second roller seat 321 drives the movable block 46 to move in the door opening direction, and at this time, the movable block 46 moves along the first swing link 41 during the movement, because the movable block 46 and the guide portion 450 of the connecting member 45 slide relatively, the movable block 46 moves obliquely upward in the door opening direction when the first swing link 41 slides, so that the user needs to apply a force to pull the movable block through this distance, and then the movable block 46 crosses the rotating shaft 47 to enter the second swing link 42, the movable block 46 presses the second swing link 42 downward, the gravity and the downward loading force of the movable block 46 are greater than the acting force of the torsion spring 43, so that the movable block 46 slides along the second swing link 42 which is inclined downward in the door opening direction (in this case, when moving in the door opening direction, the inner end of the coil spring 61 is connected to the shaft or other parts of the first roller 310, and when the first roller 310 rotates, the inner end is wound to enable the outer end to rotate continuously and wind in, the first traction rope 62 connected with the outer end is also wound in a linkage manner to further pull the movable block to move downwards), so that the force application distance of a user is the distance from the initial position of the movable block 46 to the rotating shaft 47 hinged with the first swing rod 41 and the second swing rod 42, the hand can be released after the distance passes through the rotating shaft 47, the door body 1 can continue to move towards the door opening direction without applying force;

until the movable block 46 falls down from the edge of the second swing link 42 and falls onto the second slide rail 44; at this time, the second swing link 42 is jacked up to restore the original state through the torsion spring 43 without the gravity of the movable block 46 and the loading force of the coil spring 61; the second swing link 42 tilts upward, so that the lower surface of the second swing link 42 and the second slide rail 44 form a channel 48 for the movable block 46 to pass through, the movable block 46 moves reversely through the inclined surface 440 of the second slide rail 44, and then the second roller 320 is driven to move reversely, the coil spring 61 also rotates reversely to be loosened, and the movable block 46 no longer has a loading force pulling downward; then, the movable block 46 moves below the first swing link 41, strikes the free end of the first swing link 41, and finally goes over the first swing link 41 to return to the original position;

the movable block 46 sequentially and circularly slides from the first and

second swing rods

41, 42 and the second slide rail 44, so as to realize the functions of semi-automatic door opening and automatic door closing;

it should be noted that, in order to prevent the excessive impact generated during the automatic door closing, the present embodiment further provides a buffer member 7, and the buffer member 7 is installed on the first roller seat 311; the buffer 7 includes a housing 71, a push rod 72 and a second elastic body (not shown), wherein the second elastic body (not shown) and the push rod 72 are mounted on the housing 71, and two ends of the second elastic body (not shown) respectively act on an inner wall of the housing and one end of the push rod 72; the buffer member 7 moves reversely along with the pulley assembly 3, and drives the other end of the pushing rod 72 to push against the side wall of the frame 2;

furthermore, if the door needs to be opened for a long time, the moving door can be limited to the door opening state, when in use, only the first slide rail 20 and/or the second slide rail 44 needs to be provided with a limiting groove 8, the limiting groove 8 is used for placing and limiting the second roller 320 and/or the movable block 46 of the pulley assembly 3, that is, the second slide rail 44 can be provided with a limiting groove 8, and the limiting groove 8 is located between the edge of the second swing rod 42 and the maximum door opening position, so that the door body 1 can be driven by hands to move, and the movable block 46 enters the limiting groove 8, so as to realize the state of being always opened; the limiting groove 8 is formed between the edge of the second swing rod 42 and the maximum door opening position, so that the semi-automatic door opening and automatic door closing functions can be normally used when the limiting groove 8 is not formed;

example 2: referring to figures 1 and 6-8,

the same parts of embodiment 2 as embodiment 1 are not repeated, and the differences are:

that is, the direction of the loading force applied to the movable block 46 is different, in the embodiment 1, the movable block 46 is pulled downwards by the first traction rope 62, and in the embodiment, the movable block 46 is pressed downwards; the loading element 6 of the present embodiment employs a first spring 63, the first spring 63 is sleeved on the guiding portion 450 of the connecting element 45, and one end of the first spring 63 acts on the lower surface of the top of the frame body 2, and the other end of the first spring is supported against the upper end of the movable block 46; in this way, the loading force applied to the movable block 46 can be conveniently adjusted (the acting force of the first spring 63 can be adjusted by adjusting the distance between the inner surface of the upper end of the frame body 2 and the movable block 46, and the adjustment function can be realized by quickly replacing the first spring 63, so that the door opening and closing speed can be adjusted by adjusting the loading force of the first spring 63 on the movable block 46, and a good adjustment effect is achieved;

example 3: referring to figures 1 and 9-12,

the same parts of this embodiment 3 as those of

embodiments

1 and 2 are not repeated, and the differences are:

this embodiment also takes the form of a pull-down activity block 46 as an example; the loading part 6 comprises a second spring 64 and a second traction rope 65, the second spring 64 is arranged in parallel with the first slide rail 20, one end of the second spring is fixed at the first roller seat 311 or the side part of the frame body 2, and the other end of the second spring is connected with the second traction rope 65; the other end of the second traction rope 65 is fixed with the lower surface of the movable block 46; the middle of the second traction rope 65 is acted by the shaft of the second roller 320, that is, when the movable block 46 moves up and down along the guide part 450 of the connecting piece 45, the second spring 64 is pulled, and the elastic force of the second spring 64 gives a downward pulling force to the second traction rope 65, so that the movable block 46 is pressed downwards all the time and exceeds the acting force of the first elastic body 43 (torsion spring 43), and the mode has the advantages of simpler structure, easy realization and low cost;

example 4: with reference to figures 1-13 of the drawings,

the parts of this embodiment 4 that are the same as

embodiments

1, 2 and 3 are not repeated, and the differences are:

in this embodiment 4, the movable block 46 is self-weighted to realize the functions of semi-automatic door opening and automatic door closing, that is, the gravity of the movable block 46 is greater than the acting force of the first elastic body 43, and the movable block 46 can also press the second swing link 42 to tilt downward, and the movable block 46 moves along the tilting direction, so as to realize the effect of automatic door opening by hand release;

The description of the above specification and examples is intended to illustrate the scope of the invention, but should not be construed as limiting the scope of the invention.

Claims

1. A door moving device comprises a door body, a frame body and a pulley assembly, wherein the door body slides through a first sliding rail hung on the frame body through the pulley assembly; the method is characterized in that: the pulley assembly is arranged between the pulley assembly and the frame body; the door opening and closing assembly comprises a first swing rod, a second swing rod, a first elastic body, a second sliding rail, a connecting piece and a movable block;

2. A sliding door apparatus as claimed in claim 1, wherein: the gravity of the movable block is greater than the acting force of the first elastic body.

3. A sliding door apparatus as claimed in claim 1, wherein: the loading piece is arranged in the frame body; the loading piece acts on the movable block to enable the movable block to sequentially and circularly displace on the first swing rod, the second swing rod and the second slide rail.

4. A sliding door apparatus as claimed in claim 3, wherein: the loading part comprises a coil spring and a first traction rope, the pulley assembly at the inner end of the coil spring is fixedly connected, and the outer end of the coil spring is connected with the lower surface of the movable block through the traction rope; when the pulley assembly moves towards the door opening direction along the first sliding rail, the inner end of the coil spring is driven to wind tightly continuously, and meanwhile, the traction rope pulls the movable block to press and slide along the first swing rod and the second swing rod; when the pulley assembly moves towards the door closing direction along the second sliding rail, the pulley assembly rotates reversely, so that the outer end of the coil spring rotates reversely.

5. A sliding door apparatus as claimed in claim 3, wherein: the loading piece is a first spring, the first spring is sleeved on the guide part on the connecting piece, one end of the first spring acts on the inner top surface of the frame body, and the other end of the first spring is supported on the upper end of the movable block.

6. A sliding door apparatus as claimed in claim 3, wherein: the loading piece comprises a second spring and a second traction rope, the second spring is arranged in parallel to the first slide rail, one end of the second spring is fixed on the side part of the frame body, and the other end of the second spring is connected with the second traction rope; the other end of the second traction rope is fixed with the lower surface of the movable block.

7. A sliding door apparatus as claimed in claim 1, wherein: and the first sliding rail and/or the second sliding rail are/is also provided with a limiting groove, and the limiting groove is used for limiting the roller and/or the movable block of the pulley component.

8. A sliding door apparatus as claimed in any one of claims 1 to 7, wherein: the pulley assembly comprises a first pulley block and a second pulley block which are sequentially arranged on the door body at intervals towards the door opening direction; the first pulley block and the second pulley block respectively comprise a first roller, a second roller, a first roller seat and a second roller seat, and the first roller and the second roller are respectively arranged on the first roller seat and the second roller seat;

the switch door assembly is arranged on the second roller seat.

9. A sliding door apparatus as claimed in claim 8, wherein: the buffer piece is arranged on the first roller seat; the buffer piece comprises a shell, a push rod and a second elastic body, wherein the second elastic body and the push rod are arranged on the shell, and two ends of the second elastic body respectively act on the inner wall of the shell and one end of the push rod; the buffer piece moves reversely along with the pulley assembly to drive the other end of the pushing rod to be abutted against the side wall of the frame body.