CN114043155B

CN114043155B - Improved generation weldment work platform is used in processing of oil accessory

Info

Publication number: CN114043155B
Application number: CN202210024364.8A
Authority: CN
Inventors: 李沿开; 张仕杰; 宋祖洋
Original assignee: Shandong Baiyuan Technology Co Ltd
Current assignee: Shandong Baiyuan Technology Co Ltd
Priority date: 2022-01-11
Filing date: 2022-01-11
Publication date: 2022-05-27
Anticipated expiration: 2042-01-11
Also published as: CN114043155A

Abstract

The invention relates to the technical field of petroleum accessory welding, in particular to an improved welding working platform for processing petroleum accessories, which comprises a welding table and a clamping mechanism, wherein the welding table is arranged on the ground, connecting holes distributed in a matrix manner are formed in the table surface of the welding table, and the clamping mechanism is arranged at the upper end of the welding table; the invention adopts the design concept of a double-clamping mode, the whole welding machine is not only suitable for clamping tubular or rectangular workpieces, but also can be correspondingly clamped and adjusted according to the sizes of the workpieces, thereby greatly expanding the range of action objects of a welding working platform.

Description

Improved generation weldment work platform is used in processing of oil accessory

Technical Field

The invention relates to the technical field of petroleum accessory welding, in particular to an improved welding working platform for processing petroleum accessories.

Background

The processing of oil accessory often need use weldment work platform, weldment work platform is a collection welding, assembly, inspection welding process equipment as an organic whole, and it can improve work efficiency with ordinary dull and stereotyped welding bench contrast, saves raw and other materials and saves the fund, and the anchor clamps accessory of welding platform optional many patterns in the use presss from both sides tight location processing operation, still has the location accuracy simultaneously, dismantles characteristics such as convenient, nevertheless can appear following problem in weldment work platform installation use: common welding work platforms are mostly suitable for clamping workpieces with single structures, when the structures of the workpieces are changed, the welding work platforms are difficult to clamp the workpieces properly, the welding work platforms are poor in adaptability to workpiece size change, and meanwhile clamping force of the welding work platforms to the workpieces is insufficient, so that the workpieces are prone to shifting during subsequent welding and other processing.

Disclosure of Invention

Therefore, the invention provides an improved welding working platform for processing oil accessories, which can effectively solve the problems that a common welding working platform is more suitable for clamping a workpiece with a single structure, is difficult to provide proper clamping treatment for the workpiece, has poor adaptability to workpiece size change, has insufficient clamping force for the workpiece, is easy to deviate during subsequent welding treatment and the like in the installation and use process of the welding working platform in the background technology.

In order to solve the technical problems, the invention specifically provides the following technical scheme: the utility model provides an oil accessory processing is with improved generation weldment work platform, includes the welding bench and presss from both sides the dress mechanism, the welding bench arrange subaerial in, set up the connecting hole that is the matrix distribution on the mesa of welding bench, the upper end of welding bench has been placed and has been pressed from both sides the dress mechanism.

The clamping mechanism comprises a bottom plate, connecting bolts, a vertical frame, connecting plates, clamping plates, ear plates, clamping strips and clamping groups, wherein the bottom plate is arranged on the upper end face of a welding table in a bilateral symmetry manner, the bottom plate is arranged at equal intervals from front to back, one end of the bottom plate is connected with connecting holes in the welding table through the connecting bolts, the vertical frame is symmetrically arranged on the front and back of the upper end face of the bottom plate, the connecting plates are arranged on one side of the vertical frame, which is back to the connecting bolts, included angles exist between the connecting plates and the vertical frame, the clamping plates are arranged between one ends, which are far away from the vertical frame, of the adjacent connecting plates, the lower ends of the clamping plates are of circular arc structures, the convex surfaces of the circular arc structures face downwards, the ear plates are symmetrically and rotatably arranged on the front and back of one ends, which are far away from the clamping plates, of the ear plates are provided with square through grooves, the clamping strips are clamped between the adjacent square through grooves, the upper ends of the vertical frames on the same bottom plate are connected with a sub-clamping group.

The sub-clamping group comprises an electric slider, a rotary plate and a pressing plate, the electric slider is installed on one side, close to the edge of the welding table, of the stand, the rotary plate is connected between one ends, away from the stand, of the adjacent electric sliders, the pressing plate is connected to the inside of the rotary plate in a sliding mode, and the pressing plate is located above the clamping plate.

The first preferred technical scheme is as follows: a first groove is formed in one side, back to the lug plate, of the upper end of the clamping plate, an extension plate is rotatably mounted in the first groove, and the rotating center of the extension plate is close to the inner bottom wall of the first groove.

The preferred technical scheme is as follows: one side of the extension plate back to the ear plate is provided with a second groove, a supporting plate is installed in the second groove in a rotating mode, and the rotating center of the supporting plate is close to the inner top wall of the second groove.

The preferred technical scheme is three: the left end face of the bottom plate at the right end of the welding table is provided with a splicing groove, and the right end of the splicing groove is spliced with the splicing groove.

The preferable technical scheme is four: the fixed plate has been arranged to the top longitudinal symmetry of grafting recess place bottom plate, the fixed plate is installed in the looks of grudging post side face mutually, the fixed plate is located the top of returning the template, the L template has been arranged to the below of fixed plate, the horizontal segment of L template is rotated through the side of round pin axle with the grudging post and is connected, the up end of L template horizontal segment and fixed plate are connected with the arc type elastic plate towards between one side of clamping board, the pressboard is installed to the vertical section of L template, the pressboard is located between the adjacent clamping board.

The preferred technical scheme is five: the connection plate is connected with the side end of the vertical frame through a second electric sliding block.

The preferred technical scheme is six: the side end face of the vertical frame where the fixing plate is located is marked with scale marks.

The preferred technical scheme is seven: the inserting grooves are arranged from front to back at equal intervals, and the number of the inserting grooves is more than that of the inserting plates.

The preferred technical scheme is eight: the lower end surface of the supporting plate is of an outward convex arc structure, and rubber layers are arranged on the lower end surface of the supporting plate and the vertical side end surface of the extension plate.

Compared with the prior art, the invention has the following beneficial effects: 1. the improved welding working platform for processing the petroleum accessories adopts the design concept of a double clamping mode, is not only suitable for clamping tubular or rectangular workpieces integrally, but also can be correspondingly clamped and adjusted according to the sizes of the workpieces, so that the range of action objects of the welding working platform is greatly expanded, and meanwhile, the clamping mechanism can clamp the workpieces in a front-back staggered mode, and is favorable for further improving the stability of the workpieces.

2. The invention realizes the function of clamping the rectangular workpiece through the matching of the extension plate and the clamping plate, thereby avoiding the condition that the operation development of subsequent welding and the like is influenced due to the deflection of the rectangular workpiece.

3. The invention carries out certain pressing treatment on the workpiece clamped by the clamping plate through the matching among the pressing plate, the L-shaped plate, the arc-shaped elastic plate and the fixed plate, and is beneficial to improving the integral stability of the workpiece.

4. The arrangement that the right and left base plates are right opposite to each other and are inserted through the inserting plates is used for achieving the purpose of improving the stability of the base plates, and is beneficial to improving the overall stability of a workpiece in a clamping state.

Drawings

The invention is further illustrated with reference to the following figures and examples.

Fig. 1 is a schematic perspective view of the present invention.

Fig. 2 is a front view of the present invention.

Fig. 3 is a left side view of the present invention.

Fig. 4 is a sectional view taken along line B-B of fig. 3.

Fig. 5 is a sectional view taken along line a-a of fig. 2.

Fig. 6 is a perspective view of a partial structure of the clamping mechanism.

Figure 7 is a schematic perspective view of the present invention with a tubular workpiece held in place by the clamping plates.

Fig. 8 is a schematic perspective view of the rectangular workpiece clamped by the clamping plates.

Fig. 9 is a schematic perspective view of the present invention with a tubular workpiece clamped by a clamping unit.

In the figure: 1. a welding table; 2. a clamping mechanism; 20. a base plate; 200. inserting plates; 201. inserting grooves; 202. a fixing plate; 203. an L-shaped plate; 204. an arc-shaped elastic plate; 205. pressing a plate; 21. a connecting bolt; 22. erecting a frame; 23. a connector tile; 230. a second electric slide block; 24. clamping the plate; 240. an extension plate; 241. a supporting plate; 25. an ear plate; 26. clamping the strip; 27. grouping by clamps; 270. a first electric slide block; 271. a plate return; 272. and (7) pressing a plate.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments; all other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

Referring to fig. 1, 2 and 3, an improved welding work platform for processing petroleum accessories comprises a welding table 1 and a clamping mechanism 2, wherein the welding table 1 is arranged on the ground, connecting holes distributed in a matrix manner are formed in the table surface of the welding table 1, and the clamping mechanism 2 is arranged at the upper end of the welding table 1.

Referring to fig. 1, 3 and 6, the clamping mechanism 2 includes a bottom plate 20, connecting bolts 21, a vertical frame 22, connecting plates 23, clamping plates 24, ear plates 25, clamping strips 26 and a clamping group 27, the bottom plate 20 is arranged on the upper end surface of the welding table 1 in a bilateral symmetry manner, the bottom plate 20 is arranged equidistantly from front to back, one end of the bottom plate 20 is connected with the connecting holes on the welding table 1 through the connecting bolts 21, the vertical frame 22 is symmetrically arranged on the front and back of the upper end surface of the bottom plate 20, the connecting plates 23 are arranged on one side of the vertical frame 22 opposite to the connecting bolts 21, an included angle exists between each connecting plate 23 and the vertical frame 22, the clamping plates 24 are arranged between one ends of the adjacent connecting plates 23 far away from the vertical frame 22, the lower ends of the clamping plates 24 are in an arc structure, the convex surfaces of the arc structure face downwards, the ear plates 25 are symmetrically rotatably arranged on the front and back of the ends of the adjacent connecting plates 23 far away from the vertical frame 22 through pin shafts, one ends of the ear plates 25 far away from the clamping plates 24 are provided with square through grooves, clamping strips 26 are clamped between adjacent square through grooves, the clamping strips 26 are clamped with lug plates 25, a sub-clamping group 27 is connected between the upper ends of the vertical frames 22 on the same bottom plate 20, the distance between the clamping plates 24 which are right opposite to each other on the left is adjusted according to the width dimension of a workpiece to be clamped, the adjustment of the distance between the clamping plates 24 can be realized by changing the installation position of the connecting bolt 21, after the adjustment of the distance between the clamping plates 24 is finished, the workpiece is clamped between the clamping plates 24 in a manual mode, then the workpiece can be welded and the like, the clamping plates 24 can clamp tubular or rectangular workpieces with larger dimensions and can adapt to the change of the dimensions of the workpieces, meanwhile, the clamping plates 24 can clamp the workpieces in a front-back staggered mode by changing the positions between the bottom plates 20, and the stability of the workpieces can be further improved.

Referring to fig. 3, 6 and 9, the clamping group 27 includes a first electric slider 270, a return plate 271 and a pressing plate 272, the first electric slider 270 is installed on one side of the vertical frame 22 near the edge of the welding table 1, the return plate 271 is connected between the ends of the adjacent first electric sliders 270 far from the vertical frame 22, the pressing plate 272 is slidably connected inside the return plate 271, the pressing plate 272 is located above the clamping plate 24, a smaller tubular or rectangular workpiece is manually placed between the inclined plate and the vertical frame 22, then the clamping plate 24 is manually pulled out and then the clamping strip 26 is rotated upwards, the clamping plate 24 drives the ear plate 25 to synchronously rotate until the clamping plate 24 presses on the workpiece, then the pressing plate 272 is manually pushed towards the clamping plate 24 for a corresponding distance, the return plate 271 is driven downwards by the first electric slider 270, the pressing plate 272 moves synchronously with the clamping plate 24, until the pressing plate 272 presses on the clamping plate 24, the tubular or rectangular workpiece with smaller size is fixed, and then the workpiece can be welded, and so on, in summary, the clamping plate 24 is pressed down by the sub-clamping group 27, so that the tubular or rectangular workpiece with smaller size can be locked in the structure formed by the vertical frame 22, the connecting plate 23 and the clamping plate 24, and further the sub-clamping group 27 can realize the function of clamping the tubular or rectangular workpiece with smaller size, and the range of the action object of the working platform is expanded.

Referring to fig. 4, 5 and 6, a first groove is formed in one side of the upper end of the clamping plate 24, which is back to the ear plate 25, an extension plate 240 is rotatably mounted in the first groove, a rotation center of the extension plate 240 is close to an inner bottom wall of the first groove, when a rectangular workpiece is clamped, the extension plate 240 is manually rotated downwards until the extension plate 240 is overlapped on the inner bottom wall of the first groove, at this time, the extension plate 240 is in a horizontal state, then the rectangular workpiece is manually placed on the extension plate 240 in the horizontal state, and the function of clamping the rectangular workpiece is realized through the matching between the extension plate 240 and the clamping plate 24, so that the situation that the subsequent welding and other operations are affected due to the deflection of the rectangular workpiece is avoided.

Referring to fig. 4, 5 and 6, a second groove is formed in one side of the extension plate 240 facing away from the ear plate 25, a supporting plate 241 is rotatably installed in the second groove, a rotation center of the supporting plate 241 is close to an inner top wall of the second groove, during the downward rotation of the extension plate 240, the supporting plate 241 is naturally separated from the second groove, when the extension plate 240 is in a horizontal state, the supporting plate 241 is adjusted manually to be perpendicular to the extension plate 240, a side end surface of the supporting plate 241 in a vertical state is attached to an inner side wall of the second groove, at this time, a lower end of the supporting plate 241 is attached to an inner concave surface at a lower end of the clamping plate 24, and the supporting plate 241 can play a role of bottom support on the extension plate 240, so as to achieve the purpose of improving the stability of the extension plate 240 and be beneficial to reducing the probability of deviation of a rectangular workpiece.

Referring to fig. 5, the lower end surface of the supporting plate 241 is of an outward convex arc structure, rubber layers are mounted on the lower end surface of the supporting plate 241 and the vertical side end surface of the extending plate 240, and the rubber layers can increase friction between the supporting plate 241 and the clamping plate 24 and between the extending plate 240 and the workpiece, so that the stability of the supporting plate 241 in a vertical state and the effect of the extending plate 240 on the workpiece are improved.

Referring to fig. 3, 4 and 6, the insertion plates 200 are symmetrically installed in front and back of the right end face of the bottom plate 20 at the left end of the welding table 1, the insertion groove 201 is formed in the left end face of the bottom plate 20 at the right end of the welding table 1, the right end of the insertion plate 200 is inserted into the insertion groove 201, and the left and right opposite bottom plates 20 are inserted into each other through the insertion plates 200, so that the purpose of improving the stability of the bottom plate 20 is achieved, and the overall stability of a workpiece in a clamping state is improved.

Referring to fig. 1, 3, 5 and 7, the fixing plates 202 are symmetrically arranged in front and back directions above the bottom plate 20 where the inserting groove 201 is located, the fixing plates 202 are installed on opposite sides of the vertical frame 22, the fixing plates 202 are located above the returning plates 271, L-shaped plates 203 are arranged below the fixing plates 202, horizontal sections of the L-shaped plates 203 are rotatably connected with side ends of the vertical frame 22 through pins, an arc-shaped elastic plate 204 is connected between an upper end surface of the horizontal section of the L-shaped plate 203 and one side of the fixing plates 202 facing the clamping plates 24, pressing plates 205 are installed on vertical sections of the L-shaped plates 203, the pressing plates 205 are located between adjacent clamping plates 24, the L-shaped plates 203 are rotated upwards manually, the L-shaped plates 203 drive the pressing plates 205 to move synchronously, the arc-shaped elastic plates 204 are synchronously pressed by the L-shaped plates 203 until the L203 reaches corresponding positions, then the workpiece is placed on the clamping plates 24, and then the L-shaped plates 203 are loosened, the L-shaped plate 203 drives the pressing plate 205 to move downward synchronously under the resilience of the arc-shaped elastic plate 204, and the pressing plate 205 is finally pressed on the workpiece, in summary, under the cooperation among the pressing plate 205, the L-shaped plate 203, the arc-shaped elastic plate 204 and the fixing plate 202, the workpiece clamped and fixed by the clamping plate 24 can be pressed to a certain extent, which is beneficial to improving the overall stability of the workpiece.

Referring to fig. 6, the side end face of the stand 22 where the fixing plate 202 is located is marked with scale lines, and in the case of the scale lines, a worker can record the displacement of the connecting plate 23 within the operation range of the worker in real time, so that the worker can perform rapid adjustment later.

Referring to fig. 4, the insertion grooves 201 are equidistantly arranged from front to back, the number of the insertion grooves 201 is greater than that of the insertion plates 200, and when the insertion plates 200 are inserted into the insertion grooves 201 close to the side ends of the bottom plate 20, the bottom plate 20 is staggered front to back, and the clamping plates 24 are synchronously staggered front to back.

Referring to fig. 6, the connecting plate 23 is connected to the side end of the vertical frame 22 through the second electric slider 230, the second electric slider 230 drives the connecting plate 23 to move downward, the connecting plate 23 drives the clamping plate 24 to move synchronously, and the distance between the clamping plate 24 and the welding table 1 is adjusted, so as to achieve the purpose of adapting to the height of a worker or the height that the worker is accustomed to operating.

During work, a large-size workpiece is clamped: the distance between the clamping plates 24 which are right and left opposite is adjusted according to the width dimension of the workpiece to be clamped, the adjustment of the distance between the clamping plates 24 can be realized by changing the installation position of the connecting bolt 21, and after the adjustment of the distance between the clamping plates 24 is finished, the workpiece is clamped between the clamping plates 24 in a manual mode, and the operation is aimed at clamping the large-size tubular workpiece.

When a large-size rectangular workpiece is clamped, before the workpiece is placed on the clamping plate 24, the extension plate 240 is manually rotated downwards until the extension plate 240 is overlapped on the inner bottom wall of the first groove, at the moment, the extension plate 240 is in a horizontal state, the supporting plate 241 is naturally separated from the second groove during the downward rotation of the extension plate 240, when the extension plate 240 is in the horizontal state, the supporting plate 241 is manually adjusted to be perpendicular to the extension plate 240, the side end surface of the supporting plate 241 in a vertical state is attached to the inner side wall of the second groove, at the moment, the lower end of the supporting plate 241 is abutted against the inner concave surface at the lower end of the clamping plate 24, and then the rectangular workpiece is manually placed on the extension plate 240 in the horizontal state.

Pressing and treating the clamped large-size workpiece: the L-shaped plate 203 is rotated upwards in a manual mode, the L-shaped plate 203 drives the pressing plate 205 to move synchronously, the arc-shaped elastic plate 204 is extruded by the L-shaped plate 203 synchronously until the L-shaped plate 203 reaches the corresponding position, then a workpiece is placed on the clamping plate 24, the L-shaped plate 203 is loosened later, the L-shaped plate 203 drives the pressing plate 205 to move downwards synchronously under the resilience of the arc-shaped elastic plate 204, and the pressing plate 205 is finally pressed on the workpiece.

Clamping a smaller-size workpiece: manually placing a smaller-sized tubular or rectangular workpiece between the inclined plate and the vertical frame 22, manually pulling out the clamping strip 26, then upwardly rotating the clamping plate 24, driving the lug plates 25 to synchronously rotate by the clamping plate 24 until the clamping plate 24 presses on the workpiece, then manually pushing the pressing plate 272 towards the clamping plate 24 by a corresponding distance, then driving the returning plate 271 to downwardly move by the first electric slider 270, synchronously moving the pressing plate 272 with the clamping plate 24 until the pressing plate 272 presses on the clamping plate 24, and locking the smaller-sized workpiece in a structure consisting of the vertical frame 22, the connecting plate 23 and the clamping plate 24.

Post-processing of workpieces: after the workpiece is clamped, the workpiece can be subjected to post-treatment operations such as welding and the like.

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

Claims

1. The utility model provides an oil accessory processing is with improved generation weldment work platform, includes welding bench (1) and presss from both sides dress mechanism (2), its characterized in that: the welding table (1) is arranged on the ground, connecting holes distributed in a matrix shape are formed in the table top of the welding table (1), and a clamping mechanism (2) is arranged at the upper end of the welding table (1);

the clamping mechanism (2) comprises a bottom plate (20), connecting bolts (21), vertical frames (22), connecting plates (23), clamping plates (24), ear plates (25), clamping strips (26) and sub-clamping groups (27), the bottom plate (20) is arranged on the upper end face of the welding table (1) in a bilateral symmetry mode, the bottom plate (20) is arranged from front to back at equal intervals, one end of the bottom plate (20) is connected with a connecting hole in the welding table (1) through the connecting bolts (21), the connecting bolts (21) on the same bottom plate (20) are arranged in a front-back symmetry mode, the vertical frames (22) are symmetrically arranged on the front and back of the upper end face of the bottom plate (20), the connecting plates (23) are arranged on one side, back to the connecting bolts (21), of the connecting plates (23) and the vertical frames (22) form an included angle, the clamping plates (24) are arranged between the ends, far away from the vertical frames (22), of the adjacent connecting plates (23), the lower end of each clamping plate (24) is of an arc structure, the convex surface of each arc structure faces downwards, ear plates (25) are symmetrically and rotationally mounted in a front-back mode through pin shafts between the ends, far away from the vertical frames (22), of the adjacent connecting plates (23), square through grooves are formed in the ends, far away from the clamping plates (24), of the ear plates (25), clamping strips (26) are clamped between the adjacent square through grooves, the clamping strips (26) are clamped with the vertical frames (22), and sub-clamping groups (27) are connected between the upper ends of the vertical frames (22) on the same bottom plate (20);

the clamping group (27) comprises an electric slider (270), a clip plate (271) and a pressing plate (272), wherein the electric slider (270) is installed on one side, close to the edge of the welding table (1), of the vertical frame (22), the clip plate (271) is connected between one ends, far away from the vertical frame (22), of the adjacent electric sliders (270), the clip plate (272) is connected with the pressing plate (272) in a sliding mode, and the pressing plate (272) is located above the clamping plate (24).

2. The improved welding work platform for processing oil accessories as claimed in claim 1, wherein: a first groove is formed in one side, back to the ear plate (25), of the upper end of the clamping plate (24), an extension plate (240) is rotatably mounted in the first groove, and the rotating center of the extension plate (240) is close to the inner bottom wall of the first groove.

3. The improved welding work platform for processing oil accessories as claimed in claim 2, wherein: extension board (240) one side back to otic placode (25) seted up No. two recesses, fagging (241) are installed to No. two recess rotations, the rotation center of fagging (241) is close to the interior roof of No. two recesses.

4. The improved welding work platform for processing oil accessories as claimed in claim 1, wherein: the plug board (200) is symmetrically installed in front of and behind the right end face of the bottom plate (20) at the left end of the welding table (1), the plug-in groove (201) is formed in the left end face of the bottom plate (20) at the right end of the welding table (1), and the right end of the plug board (200) is plugged with the plug-in groove (201).

5. The improved welding work platform for processing oil accessories as claimed in claim 4, wherein: the utility model discloses a clamping plate (24) is fixed to the side of the back of the side of inserting groove (201) place bottom plate (20), fixed plate (202) have been arranged to the front and back symmetry in the top of stand (22), the side of the back of the body that is carried forward in fixed plate (202), fixed plate (202) are located return type board (271), L template (203) have been arranged to the below of fixed plate (202), the horizontal segment of L template (203) is connected through the round pin axle with the side rotation of stand (22), be connected with between the up end of L template (203) horizontal segment and fixed plate (202) one side towards clamping plate (24) arc type elastic plate (204), pressboard (205) are installed to the vertical section of L template (203), pressboard (205) are located between adjacent clamping plate (24).

6. The improved welding work platform for processing oil accessories as claimed in claim 1, wherein: the connecting plate (23) is connected with the side end of the stand (22) through a second electric sliding block (230).

7. The improved welding work platform for processing the oil fittings as recited in claim 5, wherein: the side end face of the vertical frame (22) where the fixing plate (202) is located is marked with scale marks.

8. The improved welding work platform for processing oil accessories as claimed in claim 4, wherein: the plug-in grooves (201) are arranged from front to back at equal intervals, and the number of the plug-in grooves (201) is more than that of the plug boards (200).

9. The improved welding work platform for processing oil accessories as claimed in claim 3, wherein: the lower end surface of the supporting plate (241) is of an outward convex arc structure, and rubber layers are mounted on the lower end surface of the supporting plate (241) and the vertical side end surface of the extension plate (240).