CN220112332U - Horizontal demoulding device for cold isostatic pressing forming of porous metal tube - Google Patents

Abstract

The utility model discloses a horizontal demoulding device for cold isostatic compaction of a porous metal tube, which comprises a fixed base, wherein a rear support frame, a sliding support frame, a front support frame and a hydraulic lifting platform are arranged on the fixed base; the rear supporting frame is arranged at one end of the fixed base, at least one hydraulic cylinder is arranged on the rear supporting frame, and a piston rod of the hydraulic cylinder is connected with the demoulding positioning device; the sliding support frame is arranged in the middle of the fixed base in a sliding way, and is provided with a demoulding positioning device; the front support frame is arranged at the other end of the fixed base, and a clamping assembly is arranged on the front support frame in a sliding manner; the hydraulic lifting platform is arranged between the rear supporting frame and the front supporting frame and penetrates through the sliding supporting frame, and the die is a porous metal tube die formed by cold isostatic pressing.

Description

Horizontal demoulding device for cold isostatic pressing forming of porous metal tube

Technical Field

The utility model relates to the technical field of demoulding devices, in particular to a horizontal demoulding device for cold isostatic pressing forming of a porous metal tube.

Background

Powder metallurgy forming is to load loose (metal, ceramic, or other material) powder into a specific mold, produce a semi-finished product with predetermined geometry, size, density, and strength under pressure, and then to form a semi-finished blank by demolding. The cold isostatic pressing technology is one of important technologies in the powder metallurgy industry, and the forming blank has relatively uniform density, is not easy to deform and crack during sintering, and has been widely used for forming hard alloy, refractory metal and other various powder materials. In industrial production, the porous metal tube is produced by cold isostatic pressing and then is demolded by a demolding device.

The practicality of the existing demoulding device is not high, a plurality of persons are required to cooperate in the demoulding process to carry out demoulding, so that the waste of manpower and material resources is caused, and the production efficiency is low. Meanwhile, the existing demolding device is not strong in universality, and if the demolding device is designed for a specification of porous metal tube, great waste is caused.

Disclosure of Invention

The utility model aims to provide a horizontal demoulding device for cold isostatic pressing forming of a porous metal tube, which reduces labor intensity, improves production efficiency, is suitable for demoulding of cold isostatic pressing forming moulds of porous metal tubes with different specifications and sizes, reduces manufacturing cost and labor intensity, and improves production efficiency.

The technical scheme provided by the utility model is as follows:

a horizontal demoulding device for cold isostatic compaction of a porous metal tube is characterized in that:

the hydraulic lifting device comprises a fixed base, wherein a rear supporting frame, a sliding supporting frame, a front supporting frame and a hydraulic lifting platform are arranged on the fixed base;

the rear support frame is arranged at one end of the fixed base, at least one hydraulic cylinder is arranged on the rear support frame, and a piston rod of the hydraulic cylinder is connected with the demoulding positioning device;

the sliding support frame is arranged in the middle of the fixed base in a sliding manner, and is provided with a demoulding positioning device;

the front support frame is arranged at the other end of the fixed base, and a clamping assembly is arranged on the front support frame in a sliding manner;

the hydraulic lifting platform is arranged between the rear support frame and the front support frame, penetrates through the sliding support frame and is used for conveying a die, and the die is a porous metal tube die formed by cold isostatic pressing;

in the working process, the demolding positioning device and the clamping assembly clamp the mold together, and demolding is completed under the action of the hydraulic cylinder and the clamping assembly.

Further, the demolding positioning device and the clamping end of the clamping assembly are arranged in the same plane, the sliding support frame is arranged on the fixed base in a sliding mode along the length direction, and the clamping assembly is arranged on the front support frame in a sliding mode along the width direction of the fixed base.

Further, the back support frame the sliding support frame and preceding support frame are parallel to each other and perpendicular to unable adjustment base, hydraulic cylinder is including drawing cylinder one, drawing cylinder two of parallel arrangement, draw cylinder one, draw cylinder two's cylinder body with the back support frame is connected, draw cylinder one, draw cylinder two's piston rod with the sliding support frame is connected.

Further, base sliding rails are arranged on two sides of the fixed base, the bottoms of the sliding support frames are arranged on the base sliding rails in a sliding mode, a first fixed cylinder and a second fixed cylinder are oppositely arranged inside the sliding support frames, and a first fixed clamp and a second fixed clamp are respectively arranged on a piston rod of the first fixed cylinder and a piston rod of the second fixed cylinder.

Further, the upper end and the inboard level of lower extreme of preceding support frame are provided with the support slide rail, the centre gripping support clamp is located two on the support slide rail, the side middle part of centre gripping support is provided with push-and-pull cylinder along the support slide rail direction, push-and-pull cylinder one end with preceding support frame inner wall connection, the other end with the centre gripping support is connected, the tip is provided with V type recess under the centre gripping support, and the upper end is provided with the centre gripping cylinder on V type recess central axis, the piston rod front end of centre gripping cylinder is provided with mounting fixture III.

Further, the central axis of hydraulic lifting platform with unable adjustment base's central axis keeps unanimous, hydraulic lifting platform includes support base, bracing piece, supports the cylinder, the bracing piece set up in support base bottom, support the cylinder bottom of cylinder with unable adjustment base is connected, support the piston rod of cylinder with the bracing piece is connected.

Further, the upper end of the support base is uniformly provided with a plurality of groups of rollers from left to right, the lower end of the support base is provided with a platform sliding rail, the support rod is slidably arranged on the platform sliding rail, and the support base reciprocates on the platform sliding rail through the upper end of the support rod, so that lifting is realized.

Further, the length of the supporting base is consistent with that of the fixed base, and the rollers are uniformly and semi-embedded in the supporting base from left to right in sequence.

Further, the first fixing clamp, the second fixing clamp and the third fixing clamp are of a bench structure, the upper end face of the bench structure is welded, and the lower end face of the bench structure is of a saw-tooth structure.

Further, a pulley is arranged on the contact surface of the clamping support and the supporting sliding rail;

the base slide rail is close to back support frame one end is equipped with the shutoff piece respectively, unable adjustment base bottom is provided with a plurality of support frames of arranging in proper order, support frame and ground contact part are fixed by rag bolt.

Compared with the prior art, the utility model has the beneficial effects that:

compared with the existing demoulding device, the horizontal demoulding device for cold isostatic pressing forming of the porous metal tube has the characteristics of simple structure, convenience in operation and the like; the demolding device adopts a horizontal structure, so that the danger of workers in demolding is reduced; the fixed base, the front support frame, the rear support frame and the sliding support frame are independently designed, so that the processing difficulty is reduced; the telescopic hydraulic cylinders cooperate with each other to finish operations such as demolding, resetting and the like of the die, so that the labor intensity is reduced, and the working efficiency is improved; the mold with different specifications and sizes can be demolded through the designs of the three clamps, the clamping base, the lifting platform and the like, and meanwhile, the stability of the mold during demolding is improved.

Drawings

FIG. 1 is a schematic diagram of a horizontal demolding device for cold isostatic pressing of a porous metal tube in an embodiment of the utility model;

FIG. 2 is a schematic view of a front support structure according to an embodiment of the present utility model;

FIG. 3 is a schematic view of the A-direction structure of FIG. 2;

FIG. 4 is a schematic view of a sliding support structure according to an embodiment of the present utility model;

FIG. 5 is a schematic view of the A-direction structure of FIG. 4;

FIG. 6 is a schematic view of a rear support structure according to an embodiment of the present utility model;

FIG. 7 is a schematic view of the A-direction structure of FIG. 6;

fig. 8 is a schematic structural diagram of a hydraulic lifting platform according to an embodiment of the present utility model.

The reference numerals are as follows:

1. the rear supporting frame, the hydraulic lifting platform, the fixed base, the sliding supporting frame, the front supporting frame, the clamping support, the push-pull air cylinder, the fixed clamp, the clamping air cylinder, the supporting sliding rail, the fixed air cylinder, the device comprises a first fixing cylinder, a second fixing cylinder, a first fixing clamp, a second fixing clamp, a base sliding rail, a 16 roller, a 17 drawing cylinder, a 18 drawing cylinder, a 19 die, a 20 platform sliding rail, a 21 supporting cylinder, a 22 supporting base and a 23 supporting rod.

Detailed Description

In order to make the objects, technical solutions and advantages of the embodiments of the present utility model more clear, the technical solutions of the embodiments of the present utility model will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present utility model. It will be apparent that the embodiments described below are some, but not all, embodiments of the utility model. The components of the embodiments of the present utility model generally described and illustrated in the figures herein may be arranged and designed in a wide variety of different configurations.

Accordingly, the following detailed description of the embodiments of the utility model, taken in conjunction with the accompanying drawings, is intended to represent only selected embodiments of the utility model, and not to limit the scope of the utility model as claimed. All other embodiments, which can be made by one of ordinary skill in the art without undue burden on the person of ordinary skill in the art based on the embodiments of the present utility model, are within the scope of the present utility model.

It should be understood that in the description of the embodiments of the present utility model, the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", etc. indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings are merely for convenience in describing the embodiments of the present utility model and to simplify the description, and do not indicate or imply that the devices or elements referred to must have a specific orientation, be configured and operated in a specific orientation, and therefore should not be construed as limiting the embodiments of the present utility model. Furthermore, the terms "first," "second," and the like, are used for descriptive purposes only and are not to be construed as indicating or implying a relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defining "a first" or "a second" may explicitly or implicitly include one or more of the described features. In the description of the embodiments of the present utility model, the meaning of "plurality" is two or more, unless explicitly defined otherwise.

In describing embodiments of the present utility model, it should be noted that, unless explicitly stated and limited otherwise, the terms "disposed," "mounted," "connected," and "connected" should be construed broadly, and may be, for example, fixedly connected, detachably connected, or integrally connected; can be mechanically connected, electrically connected or can be communicated with each other; can be directly connected or indirectly connected through an intermediate medium, and can be communicated with the inside of two elements or the interaction relationship of the two elements. The specific meaning of the above terms in the embodiments of the present utility model can be understood by those of ordinary skill in the art according to specific circumstances.

Referring to fig. 1, the utility model provides a horizontal demoulding device for cold isostatic pressing of a porous metal tube, which comprises a fixed base 3, wherein a rear supporting frame 1, a sliding supporting frame 4, a front supporting frame 5 and a hydraulic lifting platform 2 are arranged on the fixed base 3.

The rear support frame 1 is arranged at the left end of the fixed base 3, at least one hydraulic cylinder is arranged on the rear support frame 1, and a piston rod of the hydraulic cylinder is connected with the demoulding positioning device. In the embodiment, through holes are formed in horizontal central lines on two sides of the rear supporting frame 1, the cylinder bottom of the hydraulic cylinder is connected with the rear supporting frame 1, a piston rod of the hydraulic cylinder extends out of the through holes, and the hydraulic cylinder is connected with the demolding positioning device in the horizontal direction.

The sliding support frame 4 is arranged in the middle of the fixed base 3 in a sliding way, and the sliding support frame 4 is provided with a demoulding positioning device. The demoulding positioning device is used for fixing and moving the mould 19, and in this embodiment, the mould 19 adopts a porous metal tube mould which is formed by cold isostatic pressing. The demolding and positioning device is used for clamping one end of the mold 19, and the clamping position of the demolding and positioning device and the mold 19 is changed in the demolding process.

The front support frame 5 sets up in unable adjustment base 3 other end, and the slip is provided with the clamping assembly on the front support frame 5, and the clamping assembly is used for the other end of centre gripping mould 19. In order to ensure the demolding effect, the clamping end of the demolding positioning device and the clamping end of the clamping assembly should be arranged in the same plane, so that the mold 19 is kept horizontally demolded.

Referring to fig. 1 and 7, a hydraulic lifting platform 2 is disposed between a rear support frame 1 and a front support frame 5, and penetrates through a sliding support frame 4 to convey a mold 19 to a demolding position.

In the working process, the demolding positioning device and the clamping assembly clamp the mold 19, and the mold 19 completes demolding under the action of the hydraulic cylinder and the clamping assembly on the rear supporting frame 1.

Optionally, the clamping end of the demolding positioning device and the clamping end of the clamping component are arranged in the same plane, the sliding support frame 4 is arranged on the fixed base 3 in a sliding manner along the length direction, and the clamping component is arranged on the front support frame 5 in a sliding manner along the width direction of the fixed base 3. The sliding support frame 4 horizontally slides left and right on the fixed base 3, the clamping assembly slides back and forth in the width of the fixed base 3, and the clamping end of the demolding positioning device and the clamping end of the clamping assembly are always in the same plane.

Referring to fig. 6 and 7, the rear support frame 1, the sliding support frame 4 and the front support frame 5 are parallel to each other and perpendicular to the fixed base 3, the hydraulic cylinder comprises a first drawing cylinder 17 and a second drawing cylinder 18 which are arranged in parallel, the cylinder bodies of the first drawing cylinder 17 and the second drawing cylinder 18 are connected with the rear support frame 1, and the piston rods of the first drawing cylinder 17 and the second drawing cylinder 18 are connected with the sliding support frame 4.

Referring to fig. 4 and 5, base slide rails 15 are disposed on two sides of the fixed base 3, the bottom of the sliding support frame 4 is slidably disposed on the base slide rails 15, a first fixed cylinder 11 and a second fixed cylinder 12 are disposed in the sliding support frame 4 in opposite directions, and piston rods of the first fixed cylinder 11 and the second fixed cylinder 12 are respectively provided with a first fixed clamp 13 and a second fixed clamp 14. In the embodiment, bottoms of the first fixing cylinder 11 and the second fixing cylinder 12 are connected with the sliding support frame 4 by adopting bolts in a fastening mode, front end piston rods of the first fixing cylinder 11 and the second fixing cylinder 12 are connected with the first fixing clamp 13 and the second fixing clamp 14 in a threaded mode, and central axes of the first fixing clamp 13 and the second fixing clamp 14 in the horizontal direction are consistent with the die 19. When the piston rods of the first fixing cylinder 11 and the second fixing cylinder 12 move, the first opposite fixing clamp 13 and the second fixing clamp 14 are driven to fix the die 19, and then under the action of the piston rods of the first drawing cylinder 17 and the second drawing cylinder 18, the sliding support frame 4 drives the die 19 shell to move on the base sliding rail 15, so that the separation of the inner layer and the outer layer of the die 19 is realized.

Referring to fig. 2 and 3, the inner sides of the upper and lower ends of the front support frame 5 are horizontally provided with support slide rails 10, and the clamping support 6 is clamped between the two support slide rails 10, so that the clamping support 6 can slide on the two support slide rails 10. The middle part of the side of the clamping support 6 is provided with a push-pull cylinder 7 along the direction of the supporting slide rail 10, one end of the push-pull cylinder 7 is connected with the inner wall of the front supporting frame 5, the other end of the push-pull cylinder is connected with the clamping support 6, the lower end part of the clamping support 6 is provided with a V-shaped groove, the upper end part of the clamping support is positioned on the central axis of the V-shaped groove and is provided with a clamping cylinder 9, and the front end of a piston rod of the clamping cylinder 9 is provided with a fixing clamp III 8. In the embodiment, the bottom of the clamping cylinder 9 is connected with the upper end of the clamping support 6 through bolts, and the front end of a piston rod of the clamping cylinder 9 is fastened with the fixing clamp III 8 through threads. When the piston rod of the clamping cylinder 9 moves downwards, the fixing clamp III 8 is driven to move together, and the front end part of the die 19 is clamped and fastened by matching with the V-shaped groove; the push-pull cylinder 7 is positioned at the center of the front support frame 5 in the vertical direction, the cylinder bottom of the push-pull cylinder is connected with the support frame by adopting a bolt in a fastening way, and the front end piston rod is in threaded connection with the clamping support 6. After the shell of the die 19 is removed, the piston rod of the push-pull cylinder 7 drives the clamping support 6 to move on the supporting slide rail 10. When the clamping support 6 moves to the farthest end of the sliding rail, the product is taken off from the die 19, and the demolding is realized.

Referring to fig. 8, the central axis of the hydraulic lifting platform 2 is consistent with the central axis of the fixed base 3, the hydraulic lifting platform 2 comprises a supporting base 22, a supporting rod 23 and a supporting cylinder 21, the supporting rod 23 is arranged at the bottom of the supporting base 22, the cylinder bottom of the supporting cylinder 21 is connected with the fixed base 3, and the piston rod of the supporting cylinder 21 is connected with the supporting rod 23.

Optionally, the upper end of the support base 22 is uniformly distributed with a plurality of groups of rollers 16 from left to right, the lower end of the support base 22 is provided with a platform slide rail 20, a support rod 23 is slidably arranged on the platform slide rail 20, and the support base 22 reciprocates on the platform slide rail 20 through the upper end of the support rod 23, so that lifting is realized.

Optionally, the length of the supporting base 22 is identical to the length of the fixed base 3, and the rollers 16 are uniformly and semi-embedded in the supporting base 22 from left to right. Specifically, the support base 22 passes through the slide support frame 4. A space for the support base 22 to pass through is provided below the slide support frame 4.

Optionally, the first fixing clamp 13, the second fixing clamp 14 and the third fixing clamp 8 are all of a bench structure, the upper end face of the bench structure is welded, and the lower end face is of a saw-tooth structure. Specifically, the upper end face of the terrace structure is welded with a piston rod of the hydraulic cylinder.

Optionally, the contact surface between the clamping support 6 and the supporting slide rail 10 is provided with a pulley, so that the clamping support 6 can slide conveniently.

The left end of the base sliding rail 15 is respectively provided with a blocking block, the bottom of the fixed base 3 is provided with a plurality of supporting frames which are sequentially arranged, and the supporting frames are fixed with the ground contact part by foundation bolts.

The horizontal demoulding device for cold isostatic compaction of the porous metal tube is suitable for the cold isostatic compaction process of the porous metal tube in the powder metallurgy industry, and can demould a porous metal tube mould with the outer diameter of phi 50 mm-phi 100mm and the length of less than or equal to 2000 mm.

The utility model provides a horizontal demoulding device for cold isostatic compaction of a porous metal tube, which comprises the following working principles: in operation, the die 19 is put into the hydraulic lifting platform 2 from the left side, and the central axis of the die 19 is at the same height with the V-shaped groove of the clamping support 6 and the central axes of the first fixing clamp 13 and the second fixing clamp 14 of the sliding support frame 4 through telescopic adjustment of the piston rod of the supporting cylinder 21. After the front end clamping part of the die 19 is placed into the V-shaped groove of the clamping support 6 through the movement of the roller 16, the piston rod of the clamping cylinder 9 drives the fixing clamp III 8 to move downwards, and the die 19 is stopped after being fastened; then, piston rods of a first fixing cylinder 11 and a second fixing cylinder 12 on the sliding support frame 4 drive a first fixing clamp 13 and a second fixing clamp 14 to fasten the outer shell of the die 19; starting a hydraulic system of a first drawing cylinder 17 and a second drawing cylinder 18, enabling the sliding support frame 4 and the outer shell of the die 19 to move rightwards along the base sliding rail 15 under the action of drawing force of piston rods of the first drawing cylinder 17 and the second drawing cylinder 18, and stopping movement when the piston rods of the first drawing cylinder 17 and the second drawing cylinder 18 shrink to the shortest time so as to realize internal and external separation of the die 19; then the push-pull air cylinder 7 is started to drive the clamping support 6 to move to the farthest end along the direction of the supporting slide rail 10 to stop; at the moment, the inner core of the die 19 and the product move to the edge of the platform, and the product is taken down to realize demolding; after demolding, the push-pull air cylinder 7 is reset, the first drawing air cylinder 17 and the second drawing air cylinder 18 are reset, mold recovery is completed, piston rods of the clamping air cylinder 9, the first fixing air cylinder 11 and the second fixing air cylinder 12 are recovered, the mold is taken out from the right side of the platform, and one working cycle is finished.

The foregoing is merely illustrative of specific embodiments of the present utility model, and the scope of the present utility model is not limited thereto, but any changes or substitutions within the technical scope of the present utility model should be covered by the scope of the present utility model. Therefore, the protection scope of the present utility model shall be subject to the protection scope of the claims.

Claims (10)

1. A horizontal demoulding device for cold isostatic compaction of a porous metal tube is characterized in that:

the hydraulic lifting device comprises a fixed base, wherein a rear supporting frame, a sliding supporting frame, a front supporting frame and a hydraulic lifting platform are arranged on the fixed base;

the rear support frame is arranged at one end of the fixed base, at least one hydraulic cylinder is arranged on the rear support frame, and a piston rod of the hydraulic cylinder is connected with the demoulding positioning device;

the sliding support frame is arranged in the middle of the fixed base in a sliding manner, and is provided with a demoulding positioning device;

the front support frame is arranged at the other end of the fixed base, and a clamping assembly is arranged on the front support frame in a sliding manner;

the hydraulic lifting platform is arranged between the rear support frame and the front support frame, penetrates through the sliding support frame and is used for conveying a die, and the die is a porous metal tube die formed by cold isostatic pressing;

in the working process, the demolding positioning device and the clamping assembly clamp the mold together, and demolding is completed under the action of the hydraulic cylinder and the clamping assembly.

2. The horizontal demoulding device for cold isostatic compaction of a porous metal tube according to claim 1, wherein:

the demolding positioning device and the clamping end of the clamping assembly are arranged in the same plane, the sliding support frame is arranged on the fixed base in a sliding mode along the length direction, and the clamping assembly is arranged on the front support frame in a sliding mode along the width direction of the fixed base.

3. The horizontal demoulding device for cold isostatic compaction of a porous metal tube according to claim 2, wherein:

the rear support frame the sliding support frame and the front support frame are parallel to each other and perpendicular to the fixed base, the hydraulic cylinder comprises a first drawing cylinder and a second drawing cylinder which are arranged in parallel, the cylinder bodies of the first drawing cylinder and the second drawing cylinder are connected with the rear support frame, and the piston rods of the first drawing cylinder and the second drawing cylinder are connected with the sliding support frame.

4. A horizontal demoulding device for cold isostatic compaction of porous metal tubes according to claim 3, wherein:

the fixed base both sides are provided with the base slide rail, the bottom of sliding support frame slide set up in on the base slide rail, inside opposite direction of sliding support frame is provided with fixed cylinder one, fixed cylinder two, fixed cylinder one the piston rod of fixed cylinder two is provided with mounting fixture one, mounting fixture two respectively.

5. The horizontal demoulding device for cold isostatic compaction of a porous metal tube according to claim 4, wherein:

the upper end and the inboard level of lower extreme of preceding support frame are provided with the support slide rail, and the centre gripping support clamp is located two on the support slide rail, the side middle part of centre gripping support is provided with push-and-pull cylinder along the support slide rail direction, push-and-pull cylinder one end with preceding support frame inner wall connection, the other end with the centre gripping support is connected, the tip is provided with V type recess under the centre gripping support, and the upper end is provided with the centre gripping cylinder on V type recess central axis, the piston rod front end of centre gripping cylinder is provided with mounting fixture III.

6. The horizontal demoulding device for cold isostatic compaction of a porous metal tube according to any one of claims 1-5, wherein:

the central axis of hydraulic lifting platform with unable adjustment base's central axis keeps unanimous, hydraulic lifting platform includes support base, bracing piece, supports the cylinder, the bracing piece set up in support base bottom, support the cylinder bottom of cylinder with unable adjustment base connects, support the piston rod of cylinder with the bracing piece is connected.

7. The horizontal demoulding device for cold isostatic compaction of a porous metal tube according to claim 6, wherein:

the upper end of the support base is uniformly provided with a plurality of groups of rollers from left to right, the lower end of the support base is provided with a platform slide rail, the support rod is arranged on the platform slide rail in a sliding manner, and the support base reciprocates on the platform slide rail through the upper end of the support rod, so that lifting is realized.

8. The horizontal demoulding device for cold isostatic compaction of a porous metal tube according to claim 7, wherein:

the length of the supporting base is consistent with that of the fixed base, and the rollers are uniformly and semi-embedded in the supporting base from left to right in sequence.

9. The horizontal demoulding device for cold isostatic compaction of a porous metal tube according to claim 5, wherein:

the first fixing clamp, the second fixing clamp and the third fixing clamp are of a bench structure, the upper end face of the bench structure is welded, and the lower end face of the bench structure is of a saw-tooth structure.

10. The horizontal demoulding device for cold isostatic compaction of a porous metal tube according to claim 9, wherein:

the contact surface of the clamping support and the supporting sliding rail is provided with a pulley;

the base slide rail is close to back support frame one end is equipped with the shutoff piece respectively, unable adjustment base bottom is provided with a plurality of support frames of arranging in proper order, support frame and ground contact part are fixed by rag bolt.