CN116902836A - Abdominal auxiliary arm stepless amplitude changing device and method, crane arm assembly and crane - Google Patents

Abstract

The application discloses a stepless amplitude changing device and method for a belly-mounted auxiliary arm, a crane arm assembly and a crane, wherein the stepless amplitude changing device for the belly-mounted auxiliary arm comprises an amplitude changing guide rail and a telescopic part; the amplitude changing guide rail is fixed on the top surface of the abdomen auxiliary arm and is close to the auxiliary arm pulley; one end of the telescopic component is hinged to the top surface of the abdomen-placed auxiliary arm, the other end of the telescopic component is connected to the amplitude-changing guide rail through the sliding component, pull rods symmetrically arranged on two sides of the amplitude-changing guide rail are respectively connected to two sides of the sliding component, and the sliding component is driven to move through the telescopic component, so that stepless amplitude changing of the abdomen-placed auxiliary arm is realized. According to the application, the auxiliary arm amplitude variation angle is switched through the extension and retraction of the oil cylinder, the amplitude variation reliability is strong, the amplitude variation efficiency is high, the operation efficiency of a client is improved, and the satisfaction is increased.

Description

Abdominal auxiliary arm stepless amplitude changing device and method, crane arm assembly and crane

Technical Field

The application relates to the technical field of cranes, in particular to a stepless amplitude changing device for a belly auxiliary arm.

Background

As one configuration of the sub-arm, the abdominal sub-arm 002 is fixed to the lower left or lower right side of the boom 001. The crane is suitable for long and narrow field operation, and effectively improves the working amplitude and lifting height of the crane (shown in figure 1). In order to meet the design requirements of different working conditions, the abdomen-placed auxiliary arm is designed with an amplitude variation function.

When the abdomen-mounted auxiliary arm works, the lower side of the suspension arm rotates to a working angle through the lower hinge point 003 of the suspension arm, a hoisting steel wire rope 004 is tensioned, the pull rod 100 is mounted to the upper hinge point 005 of the suspension arm, the steel wire rope penetrates through the suspension arm pulley 006, and the auxiliary arm pulley 007 can realize hoisting operation. The pull rod 100 is connected with the abdomen-placed auxiliary arm 002 through a connecting bracket 200 and a pull plate assembly 300, the connecting bracket 200 is used for connecting the two pull rods and the pull plate assembly 300, the pull plate assembly consists of a single pull plate 301 and a double pull plate 302, the single pull plate 301 and the double pull plate 302 are connected through a pin shaft 303, and the abdomen-placed auxiliary arm amplitude variation is completed through different shaft hole matching positions of the single pull plate and the double pull plate (as shown in fig. 2 and 3).

The initial angle of the abdomen-placed auxiliary arm is generally 5 degrees, the amplitude variation of 15 degrees and 30 degrees is realized through the cooperation of single and double pulling plates, and the amplitude variation process is as follows:

so that the steel wire rope is tensioned, the pin shaft 303 and the clamp are pulled out, the pin shaft 303 and the clamp are inserted into the middle pin hole, the steel wire rope is slowly released, and when the pin shaft 303 contacts with the limit hole on the single pulling plate 301, the release of the steel wire rope is stopped. At this time, the abdominal auxiliary arm is in a 15 ° working state (as shown in fig. 4).

The wire rope is slowly retracted, so that the wire rope is tensioned, and the pin shaft 303 and the clamp are pulled out. Slowly paying out the steel wire rope, and stopping paying out the steel wire rope when the pin shaft II 304 contacts with the limiting hole on the single pulling plate 301. At this time, the sub-arm is in a 30 ° state (as shown in fig. 5).

When the amplitude changing angle of the abdomen auxiliary arm is changed from 30 degrees to 15 degrees or 5 degrees, the process is opposite to the process, and the pin shaft is inserted into the corresponding shaft hole position to change amplitude.

When the existing amplitude-changing structure is used for amplitude changing, a main arm needs to be prone to be flat, an operator ascends to plug a pin shaft, amplitude changing efficiency is low, time and labor are wasted, and safety is low.

Disclosure of Invention

The application designs a stepless amplitude changing device for a belly-mounted auxiliary arm in order to improve the amplitude changing efficiency of the belly-mounted auxiliary arm and avoid the ascending operation of operators. The stepless amplitude changing device mainly comprises an amplitude changing pressure cylinder, a pull rod, an amplitude changing guide rail, a pull rod shaft and other parts, the hydraulic cylinder is in a pressure cylinder stress mode, the amplitude changing angle of the auxiliary arm is switched through the extension and retraction of the cylinder, the amplitude changing reliability is high, the amplitude changing efficiency is high, the operation efficiency of a client is improved, and the satisfaction is improved.

The application is realized according to the following technical scheme:

in a first aspect, the application discloses a stepless amplitude variation device for an abdominal auxiliary arm, which comprises:

the amplitude changing guide rail is fixed on the top surface of the abdomen auxiliary arm and is close to the auxiliary arm pulley;

one end of the telescopic component is hinged to the top surface of the abdomen-placed auxiliary arm, the other end of the telescopic component is connected to the amplitude-changing guide rail through the sliding component, pull rods symmetrically arranged on two sides of the amplitude-changing guide rail are respectively connected to two sides of the sliding component, and the sliding component is driven to move through the telescopic of the telescopic component, so that stepless amplitude changing of the abdomen-placed auxiliary arm is realized.

In some embodiments, the section of the amplitude variation guide rail is an n-type surface, and two long guide grooves which are symmetrically arranged are respectively arranged on two side surfaces of the amplitude variation guide rail; when the sliding part is positioned at the outer end part of the guide groove, which is close to the auxiliary arm pulley, the abdomen auxiliary arm is in a 5-degree amplitude state; when the sliding part is positioned at the inner side end part of the guide groove, which is far away from the auxiliary arm pulley, the abdomen auxiliary arm is in a 30-degree amplitude state.

In some embodiments, the sliding member comprises:

the pull rod shafts are inserted into the two guide grooves of the amplitude changing guide rail, the hinged ends of the telescopic parts are connected to the pull rod shafts positioned in the amplitude changing guide rail, the pull rods at the two sides are respectively hinged to the end parts of the pull rod shafts positioned at the two outer side surfaces of the guide grooves, the pull rod shafts and the pull rods are driven to slide in the guide grooves through the telescopic of the telescopic parts,

and the first limiting component is fixed on the axial surface of the pull rod shaft and limits the pull rod on the pull rod shaft.

In some embodiments, the first limiting member is implemented by:

the pull rod shaft is of a step structure, the reaming of the pull rod is sleeved at the step end of the pull rod to limit the inner side movement of the pull rod, and the cover plate with the outer diameter larger than the step end is fixed on the axial surface of the pull rod shaft through a bolt to limit the outer side movement of the pull rod.

In some embodiments, a second limiting member is provided on the pull rod shaft for limiting axial movement thereof and axial movement of the telescoping member.

In some embodiments, the second limiting member is implemented by:

a limiting block is respectively arranged between two side surfaces of the hinged end of the telescopic component and the inner side surface of the corresponding amplitude changing guide rail;

a notch is respectively arranged on the radial surface of the pull rod shaft between the two side surfaces of the hinged end of the telescopic component and the corresponding inner side surface of the amplitude changing guide rail;

the limiting blocks at the two sides are respectively inserted into the corresponding notches and then fixed on the side surfaces of the hinged ends of the telescopic parts through bolts, and the fixed limiting blocks are also contacted with the inner side surfaces of the amplitude changing guide rails.

In some embodiments, the telescopic component is a luffing cylinder, the fixed end of the luffing cylinder is hinged on a fixed ear plate positioned on the top surface of the abdomen-placed auxiliary arm, and the movable end of the luffing cylinder is in sliding connection with the luffing guide rail.

In a second aspect, the application discloses a boom assembly comprising a boom and a belly auxiliary boom fixed on the left lower side or the right lower side of the boom, wherein the belly auxiliary boom is provided with the belly auxiliary boom stepless amplitude changing device.

In a third aspect, the application discloses a crane, which is provided with the boom assembly.

In a fourth aspect, the application discloses a stepless amplitude variation method of an abdominal auxiliary arm, which comprises the following steps:

a luffing guide rail with a long guide groove is fixed on the top surface of the abdomen-placed auxiliary arm and close to the auxiliary arm pulley;

the fixed end of the telescopic component is hinged to a fixed lug plate positioned on the top surface of the abdomen-placed auxiliary arm, and the movable end of the telescopic component and the pull rod are connected with a pull rod shaft which is slidably arranged in the guide groove;

when the amplitude-variable pressure cylinder is fully extended, the pull rod shaft is arranged at the outermost end of the guide groove of the amplitude-variable guide rail, and the abdomen-placed auxiliary arm is in an amplitude-variable state of 5 degrees; along with the retraction of the amplitude changing pressure cylinder, the pull rod shaft moves inwards in the guide groove of the amplitude changing guide rail, the auxiliary arm starts to change amplitude until the amplitude changing pressure cylinder is fully contracted, the pull rod shaft moves to the innermost end of the guide groove of the amplitude changing guide rail, and at the moment, the abdomen auxiliary arm is in a 30-degree amplitude changing state, and the stepless amplitude changing of the auxiliary arm can be realized by the extension and contraction of the amplitude changing pressure cylinder.

The application has the beneficial effects that:

1. the hydraulic cylinder stretches to realize stepless amplitude variation, so that the amplitude variation efficiency is high;

2. the pin shaft is not required to be inserted and pulled out by an operator in a ascending manner, so that the convenience of use is improved;

3. the hydraulic cylinder amplitude variation mode is adopted, so that the safety performance is high.

Drawings

The accompanying drawings, which are included to provide a further understanding of the application and are incorporated in and constitute a part of this specification, illustrate embodiments of the application and together with the description serve to explain the application. It is evident that the drawings in the following description are only examples, from which other drawings can be obtained by a person skilled in the art without the inventive effort.

In the drawings:

FIG. 1 is a prior art abdominal auxiliary arm articulated state;

the attached drawings are identified: 001: a boom; 002: a ventral auxiliary arm is arranged; 003: and the suspension arm is hinged at the lower hinge point.

FIG. 2 is a prior art abdominal auxiliary arm in use;

the attached drawings are identified: 001: a boom; 002: a ventral auxiliary arm is arranged; 003: the lower hinge point of the suspension arm; 004: hoisting the steel wire rope; 005: a hinge point on the suspension arm; 006: a boom pulley; 007: an auxiliary arm pulley; 100: a pull rod; 200: a connecting bracket; 300: and the pulling plate assembly.

FIG. 3 is a 5℃amplitude variation state and a partial enlarged view of a ventral auxiliary arm of the prior art;

the attached drawings are identified: 001: a boom; 002: a ventral auxiliary arm is arranged; 100: a pull rod; 200: a connecting bracket; 301: a single pulling plate; 302: double pulling plates; 303: and a pin shaft.

FIG. 4 is a 15℃amplitude variation state and a partial enlarged view of a prior art abdominal auxiliary arm;

the attached drawings are identified: 001: a boom; 002: a ventral auxiliary arm is arranged; 100: a pull rod; 200: a connecting bracket; 301: a single pulling plate; 302: double pulling plates; 303: and a pin shaft.

FIG. 5 is a 30℃amplitude variation state and a partial enlarged view of a prior art abdominal auxiliary arm;

the attached drawings are identified: 001: a boom; 002: a ventral auxiliary arm is arranged; 100: a pull rod; 200: a connecting bracket; 301: a single pulling plate; 302: double pulling plates; 304: and a pin II.

FIG. 6 is an exploded view of the abdominal auxiliary arm stepless luffing device of the present application;

the attached drawings are identified: 100: a pull rod; 401: a variable amplitude pressure cylinder; 402: a luffing guide rail; 403: fixing the ear plate; 404: a pull rod shaft; 405: a cover plate; 406: a limiting block; 407: and (5) a bolt.

FIG. 7 is an electrodeless amplitude variation 5 degree amplitude variation state and a partial enlarged view of the abdomen-placed auxiliary arm stepless amplitude variation device of the application;

the attached drawings are identified: 001: a boom; 002: a ventral auxiliary arm is arranged; 100: a pull rod; 401: a variable amplitude pressure cylinder; 402: a luffing guide rail; 403: the ear plate is fixed.

FIG. 8 is an enlarged view of an electrodeless amplitude variation 30 degree amplitude variation state and a part of an abdomen-placed auxiliary arm stepless amplitude variation device;

the attached drawings are identified: 001: a boom; 002: a ventral auxiliary arm is arranged; 100: a pull rod; 401: a variable amplitude pressure cylinder; 402: and a variable amplitude guide rail.

It should be noted that these drawings and the written description are not intended to limit the scope of the inventive concept in any way, but to illustrate the inventive concept to those skilled in the art by referring to the specific embodiments.

Description of the embodiments

For the purpose of making the objects, technical solutions and advantages of the embodiments of the present application more apparent, the technical solutions in the embodiments will be clearly and completely described with reference to the accompanying drawings in the embodiments of the present application, and the following embodiments are used to illustrate the present application, but are not intended to limit the scope of the present application.

In the description of the present application, it should be noted that the directions or positional relationships indicated by the terms "upper", "lower", "front", "rear", "left", "right", "vertical", "inner", "outer", etc. are based on the directions or positional relationships shown in the drawings, are merely for convenience of describing the present application and simplifying 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 thus should not be construed as limiting the present application.

In the description of the present application, it should be noted that, unless explicitly specified and limited otherwise, the terms "mounted," "connected," and "connected" are to be construed broadly, and may be either fixedly connected, detachably connected, or integrally connected, for example; can be mechanically or electrically connected; can be directly connected or indirectly connected through an intermediate medium. The specific meaning of the above terms in the present application will be understood in specific cases by those of ordinary skill in the art.

As shown in fig. 6, 7 and 8, an abdomen-placed auxiliary arm stepless amplitude changing device comprises an amplitude changing guide rail 402 and a telescopic component; the amplitude changing guide rail 402 is fixed on the top surface of the abdomen-placed auxiliary arm 002 and is close to the auxiliary arm pulley; one end of the telescopic component is hinged to the top surface of the abdomen-placed auxiliary arm 002, the other end of the telescopic component is connected to the amplitude-changing guide rail 402 through a sliding component, the pull rods 100 symmetrically arranged on two sides of the amplitude-changing guide rail 402 are respectively connected to two sides of the sliding component, and the sliding component is driven to move through the telescopic component to realize stepless amplitude changing of the abdomen-placed auxiliary arm 002.

A preferred embodiment of the above embodiment with respect to the luffing guide rail is given below:

with continued reference to fig. 6, 7 and 8, the cross section of the luffing guide rail 402 is an n-type surface, and two long guide grooves which are symmetrically arranged are respectively arranged on two side surfaces of the luffing guide rail 402; when the sliding part is positioned at the outer end part of the guide groove, which is close to the auxiliary arm pulley, the abdomen auxiliary arm 002 is in a 5-degree amplitude state; when the sliding member is located at the inner end of the guide groove away from the sub-arm pulley, the abdominal sub-arm 002 is in a 30 ° amplitude state.

The preferable scheme is as follows: the sliding component comprises a pull rod shaft 404 and a first limiting component; the pull rod shaft 404 is inserted into two guide grooves of the amplitude changing guide rail 402, the hinged ends of the telescopic components are connected to the pull rod shaft 404 positioned in the amplitude changing guide rail 402, the pull rods 100 on two sides are hinged to the end parts of the pull rod shaft 404 positioned on two outer sides of the guide grooves respectively, the pull rod shaft 404 and the pull rod 100 are driven to slide in the guide grooves through the telescopic components, and the first limiting component is fixed on the axial surface of the pull rod shaft 404 to limit the pull rod 100 on the pull rod shaft 404.

The preferable scheme is as follows: the first limiting component is realized by the following structure: the pull rod shaft 404 has a stepped structure, the hinge hole of the pull rod 100 is sleeved at the stepped end of the pull rod 100 to limit the inner movement of the pull rod 100, and the cover plate 405 with the outer diameter larger than the stepped end is fixed on the axial surface of the pull rod shaft 404 through the bolt 407 to limit the outer movement of the pull rod.

The further scheme is as follows: with continued reference to fig. 6, a second limiting member is provided on the pull rod shaft 404 for limiting the axial movement thereof and the axial movement of the telescopic member.

The preferable scheme is as follows: the second limiting component is realized by the following structure: a limiting block 406 is respectively arranged between two side surfaces of the hinged end of the telescopic component and the inner side surface of the corresponding amplitude changing guide rail 402; a notch is respectively arranged on the radial surface of the pull rod shaft 404 between the two side surfaces of the hinged end of the telescopic component and the inner side surface of the corresponding amplitude changing guide rail 402; the limiting blocks 406 on the two sides are respectively inserted into the corresponding notches and then fixed on the side surfaces of the hinged ends of the telescopic components through bolts, and the fixed limiting blocks 406 are also contacted with the inner side surfaces of the variable-amplitude guide rails 402.

The preferable scheme is as follows: the telescopic component is an amplitude changing pressure cylinder 401, the fixed end of the amplitude changing pressure cylinder 401 is hinged on a fixed lug plate 403 positioned on the top surface of the abdomen-placed auxiliary arm 002, and the movable end of the amplitude changing pressure cylinder 401 is in sliding connection with an amplitude changing guide rail 402.

When the luffing cylinder 401 is fully extended, the pull rod shaft 404 is at the outermost end of the guide groove of the luffing guide rail 402, and the abdomen-placed auxiliary arm 002 is in a luffing state of 5 degrees (as shown in fig. 7). As the amplitude-variable cylinder 401 retracts, the pull rod shaft 404 moves inwards in the guide groove of the amplitude-variable guide rail 402, the auxiliary arm starts to amplitude, the amplitude-variable cylinder 401 is fully retracted, the pull rod shaft 404 moves to the innermost end of the guide groove of the amplitude-variable guide rail 402, and the abdomen-placed auxiliary arm 002 is in an amplitude-variable state of 30 degrees (as shown in fig. 8). The expansion and contraction of the amplitude changing pressure cylinder 401 can realize stepless amplitude changing of the auxiliary arm.

As shown in fig. 7 and 8, the application also discloses a crane arm assembly, which comprises a crane arm 001 and a belly auxiliary arm 002 fixed on the left lower side or the right lower side of the crane arm 001, wherein the belly auxiliary arm 002 is provided with the belly auxiliary arm stepless amplitude changing device.

The stepless amplitude changing device mainly comprises an amplitude changing pressure cylinder, a pull rod, an amplitude changing guide rail, a pull rod shaft and other parts, the hydraulic cylinder is in a pressure cylinder stress mode, the amplitude changing angle of the auxiliary arm is switched through the extension and retraction of the cylinder, the amplitude changing reliability is high, the amplitude changing efficiency is high, the operation efficiency of a client is improved, and the satisfaction is improved.

It should be noted that, the boom: the device is used for lifting heavy objects, can realize amplitude variation and expansion by means of an oil cylinder, is formed by butt welding two bending plates, and has a cross section similar to a rectangular structure. And when the vehicle is not in working state, the vehicle is placed in a horizontal state along the direction of the vehicle body.

The application also discloses a crane, and the crane arm assembly is installed.

In the description provided herein, numerous specific details are set forth. However, it is understood that embodiments of the application may be practiced without these specific details. In some instances, well-known methods, structures and techniques have not been shown in detail in order not to obscure an understanding of this description.

Furthermore, those skilled in the art will appreciate that while some embodiments described herein include some features contained in other embodiments, but not others, combinations of features of different embodiments are equally meant to be within the scope of the application and form different embodiments. For example, in the above embodiments, those skilled in the art can use the above embodiments in combination according to known technical solutions and technical problems to be solved by the present application.

The foregoing description is only illustrative of the preferred embodiment of the present application, and is not to be construed as limiting the application, but is to be construed as limiting the application to any simple modification, equivalent variation and variation of the above embodiments according to the technical matter of the present application without departing from the scope of the application.

Claims (10)

1. An abdominal auxiliary arm stepless amplitude changing device is characterized by comprising:

the amplitude changing guide rail is fixed on the top surface of the abdomen auxiliary arm and is close to the auxiliary arm pulley;

one end of the telescopic component is hinged to the top surface of the abdomen-placed auxiliary arm, the other end of the telescopic component is connected to the amplitude-changing guide rail through the sliding component, pull rods symmetrically arranged on two sides of the amplitude-changing guide rail are respectively connected to two sides of the sliding component, and the sliding component is driven to move through the telescopic of the telescopic component, so that stepless amplitude changing of the abdomen-placed auxiliary arm is realized.

2. The abdominal auxiliary arm stepless amplitude changing device according to claim 1, wherein:

the section of the amplitude changing guide rail is an n-type surface, and two long guide grooves which are symmetrically arranged are respectively arranged on two side surfaces of the amplitude changing guide rail;

when the sliding part is positioned at the outer end part of the guide groove, which is close to the auxiliary arm pulley, the abdomen auxiliary arm is in a 5-degree amplitude state;

when the sliding part is positioned at the inner side end part of the guide groove, which is far away from the auxiliary arm pulley, the abdomen auxiliary arm is in a 30-degree amplitude state.

3. A stepless amplitude variation device for an abdominal auxiliary arm according to claim 2, wherein the sliding member comprises:

the pull rod shafts are inserted into the two guide grooves of the amplitude changing guide rail, the hinged ends of the telescopic parts are connected to the pull rod shafts positioned in the amplitude changing guide rail, the pull rods at the two sides are respectively hinged to the end parts of the pull rod shafts positioned at the two outer side surfaces of the guide grooves, the pull rod shafts and the pull rods are driven to slide in the guide grooves through the telescopic of the telescopic parts,

and the first limiting component is fixed on the axial surface of the pull rod shaft and limits the pull rod on the pull rod shaft.

4. A stepless amplitude variation device for an abdominal auxiliary arm according to claim 3, wherein the first limiting member is realized by the following structure:

the pull rod shaft is of a step structure, the reaming of the pull rod is sleeved at the step end of the pull rod to limit the inner side movement of the pull rod, and the cover plate with the outer diameter larger than the step end is fixed on the axial surface of the pull rod shaft through a bolt to limit the outer side movement of the pull rod.

5. A stepless amplitude variation device for an abdominal auxiliary arm according to claim 3, wherein:

the pull rod shaft is provided with a second limiting component for limiting the axial movement of the pull rod shaft and the axial movement of the telescopic component.

6. The abdominal auxiliary arm stepless amplitude changing device according to claim 5, wherein the second limiting component is realized by the following structure:

a limiting block is respectively arranged between two side surfaces of the hinged end of the telescopic component and the inner side surface of the corresponding amplitude changing guide rail;

a notch is respectively arranged on the radial surface of the pull rod shaft between the two side surfaces of the hinged end of the telescopic component and the corresponding inner side surface of the amplitude changing guide rail;

the limiting blocks at the two sides are respectively inserted into the corresponding notches and then fixed on the side surfaces of the hinged ends of the telescopic parts through bolts, and the fixed limiting blocks are also contacted with the inner side surfaces of the amplitude changing guide rails.

7. The abdominal auxiliary arm stepless amplitude changing device according to claim 1, wherein:

the telescopic component is an amplitude changing pressure cylinder, the fixed end of the amplitude changing pressure cylinder is hinged to a fixed lug plate positioned on the top surface of the abdomen auxiliary arm, and the movable end of the amplitude changing pressure cylinder is in sliding connection with the amplitude changing guide rail.

8. The utility model provides a jib loading boom subassembly, includes the jib loading boom and is fixed in the abdomen of jib loading boom left downside or right downside and put the accessory arm, its characterized in that:

a stepless amplitude variation device for the abdomen-placed auxiliary arm according to any one of claims 1 to 7 is mounted on the abdomen-placed auxiliary arm.

9. A crane, characterized in that:

a boom assembly as defined in claim 8 is installed.

10. A stepless amplitude variation method of a ventral auxiliary arm is characterized in that:

a luffing guide rail with a long guide groove is fixed on the top surface of the abdomen-placed auxiliary arm and close to the auxiliary arm pulley;

the fixed end of the telescopic component is hinged to a fixed lug plate positioned on the top surface of the abdomen-placed auxiliary arm, and the movable end of the telescopic component and the pull rod are connected with a pull rod shaft which is slidably arranged in the guide groove;

when the amplitude-variable pressure cylinder is fully extended, the pull rod shaft is arranged at the outermost end of the guide groove of the amplitude-variable guide rail, and the abdomen-placed auxiliary arm is in an amplitude-variable state of 5 degrees; along with the retraction of the amplitude changing pressure cylinder, the pull rod shaft moves inwards in the guide groove of the amplitude changing guide rail, the auxiliary arm starts to change amplitude until the amplitude changing pressure cylinder is fully contracted, the pull rod shaft moves to the innermost end of the guide groove of the amplitude changing guide rail, and at the moment, the abdomen auxiliary arm is in a 30-degree amplitude changing state, and the stepless amplitude changing of the auxiliary arm can be realized by the extension and contraction of the amplitude changing pressure cylinder.