CN220883912U

CN220883912U - Auxiliary device for laying decorative wall cloth

Info

Publication number: CN220883912U
Application number: CN202322636182.9U
Authority: CN
Inventors: 黄周勇; 丁亮; 王磊; 房涛荣; 刘钊; 王辉; 王旗
Original assignee: Zhejiang Yakino Decorative Materials Co ltd
Current assignee: Zhejiang Yakino Decorative Materials Co ltd
Priority date: 2023-09-27
Filing date: 2023-09-27
Publication date: 2024-05-03
Anticipated expiration: 2033-09-27

Abstract

The utility model provides a decorative wall cloth wall laying auxiliary device, which relates to the field of wall cloth lamination, and comprises wall cloth, a telescopic rod, a glue containing box, a U-shaped rod, a paper winding roller and a leveling roller, wherein the U-shaped rod is arranged at the front end of the telescopic rod, the paper winding roller, the glue containing box and the leveling roller are sequentially arranged in the U-shaped rod from bottom to top, a glue feeding roller and a clamping device are arranged in the glue containing box, a paper inlet and a paper outlet are formed in the glue containing box, the glue feeding roller is pivoted in the glue containing box, the bottom of the wall cloth contacts with the glue feeding roller after the wall cloth enters the glue containing box, and the top of the wall cloth contacts with the leveling roller after the wall cloth passes through the glue containing box, and the clamping device is arranged in the glue containing box and corresponds to the glue feeding roller from top to bottom and is used for enabling the bottom of the wall cloth to contact with the glue feeding roller. According to the utility model, the glue containing box is arranged between the paper winding roller and the spreading roller, so that the back of the wall cloth passing through the glue containing box is coated with uniform glue, and the glue can be directly adhered to a wall surface, thereby greatly improving the convenience of wall cloth adhesion for users.

Description

Auxiliary device for laying decorative wall cloth

Technical Field

The utility model relates to the technical field of wall cloth lamination, in particular to a decorative wall cloth wall laying auxiliary device.

Background

The wall cloth is an indoor decoration material for pasting wall surfaces, and is widely used for indoor decoration of houses, offices, hotels and the like. However, the wall cloth with a certain width cannot be completely pasted on the front surface, and a certain white margin is often formed, so that the wall cloth is required to be pasted on the wall surface after being cut, but most of the current wall cloth is required to be pasted on the wall surface after glue is smeared on the back of the wall cloth. However, the wall cloth laminating device in the current market often has no function of smearing glue on the back of the wall cloth, and can only smear the glue on the back of the wall cloth and then paste the wall cloth on the wall surface, thereby greatly reducing the efficiency of workers.

Disclosure of utility model

(One) solving the technical problems

Aiming at the defects of the prior art, the utility model provides a decorative wall cloth wall laying auxiliary device, which solves the problems in the background art.

(II) technical scheme

In order to achieve the above purpose, the utility model is realized by the following technical scheme: the utility model provides a decorative wall cloth spreads wall auxiliary device, includes wall cloth, telescopic link, U-shaped pole, wind-up roll and pave the roller, the U-shaped pole is installed in the front end of telescopic link, wind-up roll and pave the roller and set up in the U-shaped pole, its characterized in that: still include holding the gluey case, the paper winding roller, hold gluey case and shop roll from supreme setting gradually in U-shaped pole down, hold gluey incasement and be provided with rubberizing roller and clamping device, hold and offered paper inlet and paper outlet on the gluey case, rubberizing roller pin joint is in holding gluey incasement, after the paper winding roller goes up the wall cloth and gets into holding the gluey case, the bottom of wall cloth contacts with rubberizing roller, after passing holding the gluey case, the top of wall cloth contacts with the shop roll, clamping device installs in the collosol incasement, and corresponds from top to bottom with rubberizing roller for make wall cloth bottom contact with rubberizing roller.

Preferably, the glue containing box further comprises a cover plate and a shell, wherein the shell is in a frame shape with an opening at the top, the cover plate is hinged to one side of the shell, the cover plate can be turned over to cover the shell, the upper rubber roller is pivoted in the shell, the clamping device is arranged at the bottom of the cover plate and comprises a paper pressing roller, and when the cover plate covers the shell, the paper pressing roller is positioned above the upper rubber roller and corresponds to the upper rubber roller up and down.

Preferably, the cover plate is provided with two threaded rods along the length direction of the cover plate, the two threaded rods penetrate through the cover plate and are in threaded connection with the cover plate, the bottoms of the two threaded rods are respectively provided with a connecting block which is in vertical sliding connection with the threaded rods, the paper pressing roller is pivoted between the two connecting blocks, and a second spring is arranged between the tops of the two connecting blocks and the bottom of the cover plate.

Preferably, a sliding groove is arranged at one side of the shell, which is far away from the paper winding roller, the sliding groove is positioned below the paper outlet, a scraping plate is arranged below the paper outlet, and the scraping plate is in sliding connection with the sliding groove; the sliding groove is characterized in that a plurality of cylindrical holes are formed in two sides of the sliding groove along the width direction of the sliding groove, and pin columns detachably connected with the cylindrical holes are arranged on the cylindrical holes and used for positioning the scraping plates.

Preferably, a tightening mechanism is arranged on the paper winding roller, the paper winding roller is connected with the U-shaped rod through the tightening mechanism, the tightening mechanism comprises two connecting rods and two blocking discs, the two connecting rods are respectively arranged at the tail parts of the two sides in the U-shaped rod, a sliding block II is sleeved on one connecting rod and is in sliding connection with the connecting rod, a spring I is sleeved on the connecting rod and is positioned between the sliding block II and the U-shaped rod, the paper winding roller is pivoted between the two blocking discs, and notches matched with the protrusions of the connecting rod and the sliding block II are respectively arranged at the tail parts of the two blocking discs and used for respectively installing the two blocking discs between the two connecting rods; the two blocking discs are internally provided with scroll springs, the center ends of the scroll springs are connected with the central shaft of the paper winding roller, and the outer ends of the scroll springs are connected with the blocking discs.

Preferably, the paper clamping plate is arranged on the leveling roller and is in sliding connection with the leveling roller, a spring III is arranged between one side, close to the leveling roller, of the paper clamping plate and the leveling roller, and when the paper clamping plate is attached to the leveling roller, the leveling roller and the paper clamping plate form a complete cylinder.

Preferably, two sides of the front end of the U-shaped rod are respectively provided with a sliding groove along the thickness direction of the U-shaped rod, a first sliding block which is in sliding connection with the sliding grooves is arranged in each sliding groove, and a fourth spring is arranged between the top of the first sliding block and the top of the sliding groove; the paper winding roller is pivoted in the sliding groove and is positioned below the first sliding block.

Preferably, the telescopic rod comprises a front rod and a rear rod, the front rod is arranged on the rear rod and is in sliding connection with the rear rod, and the U-shaped rod is arranged at the top end of the front rod.

(III) beneficial effects

The utility model provides a decorative wall cloth wall laying auxiliary device. The beneficial effects are as follows:

1. This decorative wall cloth spreads wall auxiliary device through being provided with the roll paper roller on the U-shaped pole, holding gluey case and spreading the roller to install the rubberizing between roll paper roller and spreading the roller, make the paper on the roll paper roller contact at spreading the roller after holding gluey case, make and accomplished the rubberizing simultaneously to the back of wall cloth at the process of laying the wall cloth, make things convenient for the user oneself to operate at home.

2. The decorative wall cloth wall-laying auxiliary device is characterized in that two sides of a paper winding roller are respectively provided with a tightening mechanism, the two tightening mechanisms comprise two connecting rods, a sliding block II, a paper winding roller and two blocking discs, the two connecting rods are respectively arranged at the end of a U-shaped rod, a second sliding block which is in sliding connection with the connecting rod is arranged on one connecting rod, a first spring is arranged between the second sliding block and the U-shaped rod, and the front end of the second sliding block is provided with a bulge which can slide on the connecting rod; meanwhile, the paper winding roller is pivoted between the two blocking discs, and notches matched with the two protrusions of the connecting rod and the sliding block are arranged at the tail parts of the two blocking discs, so that the blocking discs and the paper winding roller can be detachably arranged on the U-shaped rod. The spiral spring is arranged in the blocking disc, the central end of the spiral spring is connected with the central shaft of the paper winding roller, and the outer end of the spiral spring is connected with the blocking disc, so that when the paper winding roller rotates, the spiral spring rotates, the paper winding roller has a rotating force, paper on the paper winding roller is always in a tensioning state, and the paper winding roller is prevented from loosening to cause poor sizing and wall paving effects.

Drawings

FIG. 1 is a schematic diagram of the structure of the present utility model;

FIG. 2 is an exploded view of the tightening mechanism of the present utility model;

FIG. 3 is a schematic top view of the cover plate of the glue container of the present utility model;

FIG. 4 is a schematic diagram of the utility model with the cover plate of the glue container opened;

FIG. 5 is an enlarged view of a portion of FIG. 4 at A;

FIG. 6 is a partial exploded view of the top of the U-shaped bar;

FIG. 7 is a cross-sectional view of a spreader roll;

fig. 8 is a state diagram of the present utility model in use.

In the figure: the paper feeding device comprises a front rod, a rear rod, a 3U-shaped rod, a 31 sliding groove, a 32 first sliding block, a 33 fourth sliding block, a4 paper winding roller, a 41 blocking disc, a 42 first sliding block, a 43 spiral spring, a 44 connecting rod, a 45 second sliding block, a5 glue containing box, a 51 cover plate, a 52 shell, a 53 threaded rod, a 54 paper pressing roller, a 55 glue applying roller, a 56 connecting block, a 57 second sliding block, a 58 paper feeding port, a 59 paper outlet, a 510 scraping plate, a 511 sliding groove, a 512 cylindrical hole, a 513 pin, a6 flat roller, a 61 paper clamping plate, a 62 third sliding block and a 7 wall cloth.

Detailed Description

The embodiment of the utility model provides a decorative wall cloth wall laying auxiliary device, which comprises wall cloth 7, a telescopic rod, a U-shaped rod 3, a paper winding roller 4, a spreading roller 6 and a glue containing box 5, wherein the U-shaped rod 3 is arranged at the front end of the telescopic rod, and the paper winding roller 4, the glue containing box 5 and the spreading roller 6 are sequentially arranged on the U-shaped rod 3 from bottom to top. The paper winding roller 4 is used for winding the wall cloth 7 which needs to be stuck on the wall surface, a user can stick one end of the wall cloth 7 which is cut to the paper winding roller 4, wind the rest of the wall cloth 7 to the paper winding roller 4, pass the other end of the wall cloth 7 through the glue containing box 5 and clamp the glue containing box 6, stick one end of the wall cloth 7 on the wall surface through the glue containing box 6, enable the wall cloth 7 to be separated from the glue containing roller 6, enable the glue containing roller 6 to roll downwards continuously, and enable the wall cloth 7 to come out of the paper winding roller 4 continuously, pass through the glue containing box 5 and then be stuck on the wall surface. The user does not need to paste the wall cloth 7 on the wall surface after the back of the wall cloth 7 is coated with glue, so that the operation of the user is greatly facilitated.

The glue container 5 comprises a cover plate 51, a shell 52, a glue applying roller 55 and a clamping device, wherein the shell 52 is in a frame shape with an opening at the top, the cover plate 51 is hinged to one side of the shell 52 and can be turned over along one side of the shell 52, and the opening at the top of the shell 52 can be covered. A paper inlet 58 is formed in one side, close to the paper winding roller 4, of the shell 52, a paper outlet 59 is formed in one side, close to the leveling roller 6, of the upper rubber roller 55 is arranged in the shell 52 and pivoted with the shell 52, and a clamping mechanism is arranged at the bottom of the cover plate 51 and corresponds to the upper rubber roller 55 and is used for pressing the wall cloth 7 onto the upper rubber roller 55, so that the bottom of the wall cloth 7 is connected with the upper rubber roller 55. The clamping mechanism includes a platen roller 54, and when the cover plate 51 is covered on the housing 52, the platen roller 54 is located above the glue roller 55 and is in a horizontal state with the glue roller 55. The wall cloth 7 on the paper winding roller 4 passes through the paper feeding port 58 and passes through the space between the paper pressing roller 54 and the glue applying roller 55, then the glue application to the bottom of the wall cloth 7 is finished through the paper outlet 59, the wall cloth 7 is pressed down on the glue applying roller 55 by the paper pressing roller 54, the wall cloth 7 is driven by the leveling roller 6 to continuously move forwards, the glue applying roller 55 is driven to rotate so as to glue the back of the wall cloth 7, a user pours a proper amount of glue into the shell 52 to continuously contact the glue with the glue applying roller 55, the back of the wall cloth 7 is glued more uniformly, and the shell 52 close to one side of the glue applying roller 55 is arc-shaped, so that the glue applying roller 55 can be better contacted with the glue in the shell 52, and glue application is better. The cover plate 51 is provided with two threaded rods 53, and the two threaded rods 53 are on the same straight line and are arranged along the length direction of the cover plate 51. The two threaded rods 53 penetrate through the cover plate 51 and are in threaded connection with the cover plate 51, connecting blocks 56 are respectively arranged at the bottoms of the two threaded rods 53, the two connecting blocks 56 are respectively in vertical sliding connection with the two threaded rods 53, and the paper pressing roller 54 is pivoted between the two connecting blocks 56, so that a user can adjust the distance between the paper pressing roller 54 and the glue applying roller 55 according to the thickness of the wall cloth 7, and the paper pressing roller 54 and the glue applying roller 55 are prevented from clamping the wall cloth 7. Meanwhile, a second spring 57 is arranged between the top of the connecting block 56 and the bottom of the cover plate 51 and is used for resetting the connecting block 56, so that the paper pressing roller 54 is always in contact with the wall cloth 7, and the wall cloth 7 is also ensured to be in contact with the rubberizing roller 55. A sliding groove 511 is formed in the shell 52, the sliding groove 511 is located below the paper outlet 59, a scraping plate 510 is arranged below the paper outlet 59 and used for scraping redundant glue on the back of the wall cloth 7, the scraping plate 510 is vertically and slidably connected with the sliding groove 511, and a user can adjust the distance between the scraping plate 510 and the wall cloth 7 according to the requirement on the thickness of the glue on the back of the wall cloth 7. Symmetrical cylindrical holes 512 are formed in the two sides of the sliding groove 511 along the height direction of the sliding groove 511, and pin columns 513 detachably connected with the cylindrical holes 512 are adapted in the cylindrical holes 512, so that when the scraping plate 510 slides in the sliding groove 511, the scraping plate 510 is fixed in the cylindrical holes 512 by inserting the pin columns 513 in proper positions, and the uniformity of glue on the back of the wall cloth 7 is guaranteed. And the shell 52 is detachably arranged on the U-shaped rod 3, the U-shaped rod 3 is provided with a T-shaped groove, and two sides of the shell 52 are provided with T-shaped sliding blocks matched with the T-shaped groove, so that the shell 52 is arranged on the U-shaped rod 3. If the wall cloth 7 of the user does not need to be glued, the user can detach the glue containing box 5, and the wall cloth 7 is pasted on the wall surface by directly using the paper winding roller 4 and the paving roller 6.

The paper winding roller 4 is provided with a tightening mechanism, the paper winding roller 4 is connected with the U-shaped rod 3 through the tightening mechanism, the tightening mechanism comprises two connecting rods 44 and two blocking discs 41, the two connecting rods 44 are arranged at the tail end of the U-shaped rod 3, one connecting rod 44 is sleeved with a second sliding block 45 and is in sliding connection with the connecting rod, the connecting rod 44 is sleeved with a first spring 42, the first spring 42 is located between the second sliding block 45 and the U-shaped rod 3 and used for resetting the second sliding block 45, the front end of the second sliding block 45 is provided with a bulge, the paper winding roller 4 is pivoted between the two blocking discs 41, one side, far away from the paper winding roller 4, of the two blocking discs 41 is respectively provided with a notch, one notch of the two blocking discs 41 is matched with the connecting rod 44, and the notch of the other blocking disc 41 is matched with the bulge of the second sliding block 45, so that the two blocking discs 41 and the paper winding roller 4 are detachably arranged on the U-shaped rod 3, and a user can conveniently wind the paper winding cloth 7 on the paper winding roller 4. The scroll springs 43 are arranged in the two blocking discs 41, the central shafts on the two sides of the paper winding roller 4 are respectively connected with the central ends of the scroll springs 43 in the two blocking discs 41, the outer ends of the scroll springs 43 are connected with the blocking discs 41, the scroll springs 43 are folded when the paper winding roller 4 rotates, and therefore the paper winding roller 4 has a rotating force, so that wall cloth 7 on the paper winding roller 4 and wall cloth 7 attached to a wall surface are folded mutually, the wall cloth 7 is always in a tight state, and uneven gluing caused by loosening of the wall cloth 7 or uneven attachment of the wall cloth 7 to the wall surface can be effectively prevented. The paper clamping plate 61 is arranged on the paving roller 6, the paper clamping plate 61 is in sliding connection with the paving roller 6, a spring III 62 is arranged between one side of the paper clamping plate 61, which is close to the paving roller 6, and is used for pulling the paper clamping plate 61 towards the paving roller 6, a user can clamp one end of the wall cloth 7 between the paper clamping plate 61 and the paving roller 6, move the paving roller 6 to a position where the wall cloth 7 is required, enable the paving roller 6 to be attached to the wall surface, enable a part of the wall cloth 7 to be attached to the wall surface, and pull down the U-shaped rod 3 to enable the paving roller 6 to roll, so that the wall cloth 7 is separated from the position between the paper clamping plate 61 and the paving roller 6, and the operation of attaching one end of the wall cloth 7 to the wall surface is completed.

Vertical sliding grooves 31 are formed in two sides of the top of the U-shaped rod 3, a first sliding block 32 which is in sliding connection with the sliding grooves 31 is arranged in the sliding grooves 31, and a fourth spring 33 is arranged between the top of the first sliding block 32 and the sliding grooves 31 and used for resetting the first sliding block 32. The center shaft of the paving roller 6 is pivoted in the chute 31 and is positioned below the first sliding block 32, so that the first sliding block 32 always pushes the paving roller 6 to the wall surface and contacts the wall surface, and the fit between the wall cloth 7 and the wall surface is ensured. The telescopic link has included preceding pole 1 and back pole 2, and back pole 2 cover is established on preceding pole 1, and with preceding pole 1 along the length direction sliding connection of preceding pole 1 to set up the top with preceding pole 1 with U-shaped pole 3.

Working principle: when the auxiliary device for paving the wall is used, the wall cloth 7 to be adhered to the wall surface is wound to the paper winding roller 4, the cover plate 51 is opened, one exposed end of the wall cloth 7 passes through the paper inlet 58 to be in contact with the glue applying roller 55 and passes through the paper outlet 59, the wall cloth 7 is clamped between the paper clamping plate 61 and the paving roller 6, proportioned glue is added into the shell 52, the distance between the scraping plate 510 and the paper outlet 59 is adjusted, the cover plate 51 is turned over to close the shell 52, and the threaded rod 53 is adjusted to enable the wall cloth 7 to be in full contact with the glue applying roller 55. The paving roller 6 is attached to a wall surface, glue on the back of the wall cloth 7 on the paving roller 6 is contacted with the wall surface, so that the wall cloth 7 on the wall cloth 7 paving roller 6 is attached to the wall surface, the U-shaped rod 3 is pulled downwards to enable the paving roller 6 to roll, meanwhile, the wall cloth 7 on the paving roller 6 is separated from the paving roller 6, and the U-shaped rod 3 is pulled downwards continuously to enable the wall cloth 7 on the paper winding roller 4 to be attached to the wall surface.

Although embodiments of the present utility model have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made therein without departing from the principles and spirit of the utility model, the scope of which is defined in the appended claims and their equivalents.

Claims

1. The utility model provides a decorative wall cloth spreads wall auxiliary device, includes wall cloth (7), telescopic link, U-shaped pole (3), wind-up roll (4) and pave roller (6), U-shaped pole (3) are installed in the front end of telescopic link, wind-up roll (4) and pave roller (6) set up in U-shaped pole (3), its characterized in that: still include holding gluey case (5), paper winding roller (4), hold gluey case (5) and shop roll (6) follow supreme setting gradually in U-shaped pole (3) down, hold gluey incasement (5) and be provided with rubberizing roller (55) and clamping device, hold and offered paper inlet (58) and paper outlet (59) on gluey case (5), rubberizing roller (55) pin joint in holding gluey case (5), after paper winding roller (4) rubberizing cloth (7) got into hold gluey case (5), the bottom of wall cloth (7) contacted with rubberizing roller (55), after passing holding gluey case (5), the top of wall cloth (7) contacted with shop roll (6), clamping device installs in rubberizing case (5), and corresponds from top to bottom with rubberizing roller (55) for make wall cloth (7) bottom and rubberizing roller (55) contact.

2. A decorative wall covering wall-laying auxiliary device according to claim 1, wherein: the glue containing box further comprises a cover plate (51) and a shell (52), wherein the shell (52) is in a frame shape with an opening at the top, the cover plate (51) is hinged to one side of the shell (52), the cover plate (51) can be turned over to cover the shell (52), the glue feeding roller (55) is pivoted in the shell (52), the clamping device is arranged at the bottom of the cover plate (51), the clamping device comprises a paper pressing roller (54), and when the cover plate (51) covers the shell (52), the paper pressing roller (54) is located above the glue feeding roller (55) and corresponds to the glue feeding roller (55) up and down.

3. A decorative wall covering wall-laying auxiliary device according to claim 2, wherein: the cover plate (51) is provided with two threaded rods (53) along the length direction of the cover plate (51), the two threaded rods (53) penetrate through the cover plate (51) to be in threaded connection with the cover plate (51), the bottoms of the two threaded rods (53) are respectively provided with a connecting block (56) which is in vertical sliding connection with the threaded rods (53), the paper pressing roller (54) is pivoted between the two connecting blocks (56), and a second spring (57) is arranged between the tops of the two connecting blocks (56) and the bottom of the cover plate (51).

4. A decorative wall covering wall-laying auxiliary device according to claim 2, wherein: a sliding groove (511) is formed in one side, away from the paper winding roller (4), of the shell (52), the sliding groove (511) is located below the paper outlet (59), a scraper (510) is arranged below the paper outlet (59), and the scraper (510) is in sliding connection with the sliding groove (511); the two sides of the sliding groove (511) are provided with a plurality of cylindrical holes (512) along the width direction of the sliding groove (511), and the cylindrical holes (512) are provided with pins (513) detachably connected with the cylindrical holes (512) for positioning the scraping plate (510).

5. A decorative wall covering wall-laying auxiliary device according to claim 1, wherein: the paper winding machine is characterized in that a tightening mechanism is arranged on the paper winding roller (4), the paper winding roller (4) is connected with the U-shaped rod through the tightening mechanism, the tightening mechanism comprises two connecting rods (44) and two blocking discs (41), the two connecting rods (44) are respectively arranged at the tail parts of the two sides in the U-shaped rod (3), a sliding block II (45) is sleeved on one connecting rod (44) and is in sliding connection with the connecting rod (44), a spring I (42) is sleeved on the connecting rod (44), the spring I (42) is positioned between the sliding block II (45) and the U-shaped rod (3), the paper winding roller (4) is pivoted between the two blocking discs (41), and notches matched with the protrusions of the connecting rod (44) and the sliding block II (45) are respectively arranged at the tail parts of the two blocking discs (41) and are respectively arranged between the two connecting rods (44); the two blocking discs (41) are internally provided with scroll springs (43), the center ends of the scroll springs (43) are connected with the central shaft of the paper winding roller (4), and the outer ends of the scroll springs (43) are connected with the blocking discs (41).

6. A decorative wall covering wall-laying auxiliary device according to claim 1, wherein: be provided with on the shop front roller (6) and press from both sides cardboard (61), press from both sides cardboard (61) and shop front roller (6) sliding connection, it is provided with spring three (62) between one side that presss from both sides cardboard (61) and shop front roller (6) near shop front roller (6), when presss from both sides cardboard (61) and shop front roller (6) laminating, shop front roller (6) and presss from both sides cardboard (61) and form complete cylinder.

7. The decorative wall covering auxiliary device according to claim 6, wherein: sliding grooves (31) along the thickness direction of the U-shaped rod (3) are respectively arranged on two sides of the front end of the U-shaped rod (3), a first sliding block (32) which is in sliding connection with the sliding grooves (31) is arranged in each sliding groove (31), and a fourth spring (33) is arranged between the top of the first sliding block (32) and the top of the sliding groove (31); the paper winding roller (4) is pivoted in the chute (31) and is positioned below the first sliding block (32).

8. A decorative wall covering wall-laying auxiliary device according to claim 1, wherein: the telescopic rod comprises a front rod (1) and a rear rod (2), wherein the front rod (1) is arranged on the rear rod (2) and is in sliding connection with the rear rod (2), and the U-shaped rod (3) is arranged at the top end of the front rod (1).