CN219901130U

CN219901130U - Clamp for thin-wall cylindrical workpiece

Info

Publication number: CN219901130U
Application number: CN202223325730.8U
Authority: CN
Inventors: 赵云云; 李建英
Original assignee: Songyun Intelligent Technology Shanghai Co ltd
Current assignee: Songyun Intelligent Technology Shanghai Co ltd
Priority date: 2022-12-10
Filing date: 2022-12-10
Publication date: 2023-10-27
Anticipated expiration: 2032-12-10

Abstract

The utility model relates to a clamp for a thin-wall cylindrical workpiece, which relates to the field of numerical control machine tools and comprises a bottom frame, wherein a first mounting frame is slidably arranged on the bottom frame, a second mounting frame is fixedly connected to the bottom frame, rotary bearings are detachably fixed on the first mounting frame and the second mounting frame, a plurality of pneumatic clamping claws are arranged on the two rotary bearings, two ends of a workpiece penetrate through inner rings of the two rotary bearings, the pneumatic clamping claws on the two rotary bearings are clamped on outer side walls of two ends of the workpiece, and a rotary positioning mechanism is detachably fixed on the first mounting frame and the second mounting frame, so that when the workpiece rotates to a position suitable for processing, the rotary positioning mechanism locks the rotary bearings. The utility model has the effect of exposing the two ends of the workpiece by clamping the outer side walls of the two ends of the workpiece, so that the two ends of the workpiece can be conveniently processed by a processing mechanism.

Description

Clamp for thin-wall cylindrical workpiece

Technical Field

The utility model relates to the field of numerical control machine tools, in particular to a clamp for a thin-wall cylindrical workpiece.

Background

The numerical control lathe is one of the numerical control lathes widely used at present, and is mainly used for cutting machining of inner and outer cylindrical surfaces of shaft parts or disc parts, inner and outer conical surfaces of any cone angle, complex rotation inner and outer curved surfaces, cylindrical threads, conical threads and the like, and can be used for grooving, drilling, reaming, boring and the like.

Currently, when a thin-walled cylindrical workpiece is clamped on a numerical control lathe, a three-jaw chuck is generally adopted. Before actual machining is performed, an operator aligns the workpiece with the three-jaw chuck, makes the jaws on the three-jaw chuck extend into the inner wall of the cylindrical workpiece, then makes the jaws on the three-jaw chuck abut against the inner walls at two ends of the workpiece, realizes clamping operation on the workpiece, and facilitates subsequent machining.

In the actual production and processing process, the inventor finds that when processing a thin-walled cylindrical workpiece, the processing of the inner side walls at two ends of the workpiece is often required, however, a three-jaw chuck clamping mode is adopted, the three-jaw chuck covers two ends of the workpiece, a processing mechanism cannot perform specific processing operation on the inner side walls of the workpiece, and if the workpiece is placed on a processing platform, the workpiece easily shakes on the processing platform, so that the processing precision is affected, and improvement exists.

Disclosure of Invention

The utility model provides a clamp for a thin-wall cylindrical workpiece, which is convenient for a processing mechanism to process two ends of the thin-wall cylindrical workpiece.

The utility model provides a fixture for a thin-wall cylindrical workpiece, which adopts the following technical scheme:

the fixture for the thin-wall cylindrical workpiece comprises a bottom frame, a driving clamping assembly and a driven clamping assembly, wherein the driving clamping assembly is arranged on the bottom frame in a sliding manner, and the driven clamping assembly is fixedly arranged on the bottom frame;

the driving clamping assembly and the driven clamping assembly respectively comprise clamping mechanisms, and when the driving clamping assembly clamps a workpiece, the two clamping mechanisms are clamped on the outer side walls of the two ends of the workpiece; when the workpiece is disassembled, the two clamping mechanisms are far away from the workpiece;

the driving part is fixedly connected to the underframe, the driving end of the driving part is fixedly connected with the driving clamping assembly, and the driving part drives the driving clamping assembly to slide along the direction close to or far away from the driven clamping assembly.

Through adopting above-mentioned technical scheme, before carrying out processing, operating personnel can be earlier with the one end of work piece fixed on driven clamping assembly through clamping mechanism to with the other end of work piece fixed at the other end of work piece through clamping mechanism, operating personnel can promote initiative clamping assembly according to the length of actual work piece this moment, and make initiative clamping assembly slide towards the direction that is close to driven clamping assembly, make the work piece erect and be fixed in between initiative clamping assembly and the driven clamping assembly. Because the clamping mechanisms at the two ends of the workpiece are clamped and fixed on the outer side wall of the workpiece, the ports at the two ends of the workpiece are completely exposed, and the processing mechanism can conveniently process the thin-wall cylindrical workpiece. After the machining is finished, the clamping mechanism on the driving clamping assembly loosens the workpiece, the driving piece drives the driving clamping assembly to move away from the driven clamping assembly, the clamping mechanism on the driven clamping assembly loosens the workpiece, and an operator can take down the workpiece. Meanwhile, as the distance between the driving clamping assembly and the driven clamping assembly can be adjusted by the driving piece, the clamp can be suitable for clamping workpieces with different lengths, and the usability of the clamp is effectively improved.

Preferably, the clamping mechanisms (7) comprise a plurality of pneumatic clamping claws, and the pneumatic clamping claws are uniformly distributed on the peripheral sides of two ends of the workpiece in a circumferential array;

when clamping a workpiece, a plurality of pneumatic clamping claws are clamped on the outer side wall of the workpiece; when the workpiece is disassembled, the pneumatic clamping claws move towards the direction far away from the workpiece.

Through adopting above-mentioned technical scheme, through pneumatic gripper jaw, can realize the technological effect of automatic centre gripping work piece, and according to the distance that the adjustable pneumatic gripper jaw of diameter of work piece was prolonged for anchor clamps are applicable to the work piece of centre gripping different diameter sizes, further promote the usability of anchor clamps. Meanwhile, as the pneumatic clamping claws are uniformly distributed on the outer side walls of the two ends of the workpiece in a circumferential array, the stress at the two ends of the workpiece is uniform, the deformation of the workpiece due to uneven stress in the clamping processing process is reduced, and a good protection effect is formed on the workpiece.

Preferably, a base is fixedly connected to the underframe, a first mounting frame is slidably arranged on the base, and one end, away from the base, of the first mounting frame is fixedly connected with the active clamping assembly;

the drive end of driving piece with first mounting bracket fixed connection, the driving piece drive first mounting bracket is close to or keep away from the direction slip of driven clamping assembly.

Through adopting above-mentioned technical scheme, because initiative clamping component and first mounting bracket fixed connection, first mounting bracket and base cooperation of sliding can realize the complex technological effect of sliding between initiative clamping component and the chassis. When a workpiece is installed, the driving piece applies force to the first installation frame to drive the first installation frame to slide along with the driving clamping assembly in a direction approaching or separating from the driven clamping assembly; when the workpiece is disassembled after machining, the driving piece drives the driving clamping assembly to move in the direction away from the driven clamping assembly, and at the moment, an operator can disassemble the workpiece from the driven clamping assembly.

Preferably, two installation blocks which are oppositely arranged are fixedly connected to the base, sliding grooves are formed in the two installation blocks, and the two sliding grooves are oppositely arranged;

the first mounting frame comprises two sliding plates, the end parts of the two sliding plates, which are opposite, are respectively embedded into the two sliding grooves, and the two sliding plates are in sliding fit with the two mounting blocks.

Through adopting above-mentioned technical scheme, two sliding plates and two installation blocks of seting up the groove of sliding cooperate each other, can realize sliding complex technological effect between first mounting bracket and the chassis.

Preferably, the driving piece comprises a telescopic cylinder, a cylinder body of the telescopic cylinder is fixedly connected with the underframe, a cylinder shaft of the telescopic cylinder is fixedly connected with the first mounting frame, and the telescopic cylinder drives the first mounting frame to slide towards a direction close to or far away from the driven clamping assembly.

Through adopting above-mentioned technical scheme, the cylinder axle and the first mounting bracket fixed connection of flexible cylinder, the cylinder axle extension or the shrink of flexible cylinder drive first mounting bracket together with initiative clamping component is close to or is kept away from driven clamping component's direction and slides. When a workpiece is installed, a cylinder shaft of the telescopic cylinder stretches to drive the first mounting frame and the driving clamping assembly to slide towards the direction close to the driven clamping assembly; when the workpiece is required to be disassembled after machining is finished, the cylinder shaft of the telescopic cylinder retracts to drive the first mounting frame to slide along with the driving clamping assembly in the direction away from the driven clamping assembly. Through the setting of flexible cylinder, reducible operating personnel centre gripping fixed work piece in-process, manual push-and-pull initiative clamping assembly's operation effectively promotes the convenience of operating personnel centre gripping fixed work piece.

Preferably, the chassis is fixedly connected with a second mounting frame, and one end of the second mounting frame away from the chassis is fixedly connected with the driven clamping assembly.

Through adopting above-mentioned technical scheme, the technical effect of fixed connection between driven clamping assembly and the chassis can be realized to the second mounting bracket for driven clamping assembly is fixed in on the chassis.

Preferably, the driving clamping assembly and the driven clamping assembly comprise slewing bearings, and the two slewing bearings are respectively in running fit with the first mounting frame and the second mounting frame;

the first mounting frame and the second mounting frame are detachably and fixedly connected with rotary positioning mechanisms, and the two rotary positioning mechanisms control the two rotary bearings to be in a rotating or locking state;

when the rotary bearings drive the workpiece to rotate to a set position, the two rotary positioning mechanisms lock the two rotary bearings, and the two rotary bearings are fixed at the relative positions with the first mounting frame and the second mounting frame.

By adopting the technical scheme, when clamping the workpiece, an operator can align the end part of the workpiece with the rotary bearing on the second mounting frame, and pass the end part of the workpiece through the inner ring of the rotary bearing on the second mounting frame, and then the pneumatic clamping claw clamps the workpiece; and then, the cylinder shaft of the telescopic cylinder stretches to drive the first mounting frame to move together with the rotary bearing until the rotary bearing on the first mounting frame is coaxially sleeved outside the other end part of the workpiece, and the pneumatic clamping claws on the first mounting frame clamp the two ends of the workpiece. At the moment, an operator can rotate the workpiece, the workpiece is at an angle suitable for machining, the availability of the clamp is improved, and after the workpiece rotates to an angle suitable for machining, the rotary positioning mechanism enables the two rotary bearings to be locked, so that the relative position of the workpiece on the clamp is fixed, and subsequent machining procedures are facilitated. Through the setting of swivel bearing for the work piece can rotate on the anchor clamps, but swivel positioning mechanism locking work piece makes the relative position of work piece on the anchor clamps fixed simultaneously, makes operating personnel adjust work piece angle after need not to dismantle the work piece and centre gripping work piece again, effectively promotes operating personnel adjustment work piece angle in order to realize the convenience of a plurality of angle processings to the work piece.

Preferably, the first mounting frame and the second mounting frame are fixedly connected with supporting frames, the two supporting frames are matched with the inner rings of the two slewing bearings, the two slewing bearings are coaxially sleeved on the outer side walls of the two supporting frames, and the two slewing bearings are respectively in running fit with the two supporting frames.

Through adopting above-mentioned technical scheme, the support frame can realize the installation of two slewing bearing on first mounting bracket, second mounting bracket, realizes two slewing bearing and first mounting bracket, second mounting bracket normal running fit's technical effect simultaneously.

Preferably, a servo motor is arranged on the underframe, a cylinder body of the servo motor is fixedly connected with the underframe, a driving shaft of the servo motor faces the first mounting frame, the driving shaft of the servo motor is in transmission fit with an outer gear ring of the slewing bearing on the first mounting frame, and the servo motor drives the slewing bearing to rotate.

Through adopting above-mentioned technical effect, servo motor's drive shaft and the rotation bearing transmission cooperation on the first mounting bracket, when the angle of work piece needs to be adjusted, servo motor drive rotation bearing rotates, because the both ends of work piece receive pneumatic gripper jaw centre gripping to fix on rotation bearing, servo motor drive rotation bearing rotates can drive the work piece and rotate together, realizes the technological effect of automatically regulated work piece angle.

In summary, the present utility model includes at least one of the following beneficial technical effects:

1. the technical effects of clamping and fixing the outer side walls of the two ends of the thin-wall cylindrical workpiece are realized through reasonable matching and use between the driving clamping assembly and the driven clamping assembly, and meanwhile, the two ends of the workpiece are not shielded, and the processing mechanism can process the two ends of the workpiece more accurately;

2. the servo motor and the rotary bearing are reasonably matched and used, so that the technical effect of automatically rotating the workpiece can be realized, and the processing mechanism is convenient for processing different parts at two ends of the workpiece;

3. through the cooperation of sliding of first mounting bracket and chassis, can make anchor clamps be applicable to the work piece of the fixed different length and dimension of centre gripping, effectively enlarge the application range of anchor clamps, promote the usability of anchor clamps.

Drawings

Fig. 1 is a schematic view mainly showing the overall structure of a jig according to an embodiment of the present utility model.

Fig. 2 is an enlarged view a of fig. 1, mainly for illustrating a connection relationship between a mounting block and a sliding plate.

Reference numerals illustrate: 1. a chassis; 11. a servo motor; 12. a driving member; 2. a base; 21. a mounting block; 211. a slip groove; 3. a first mounting frame; 31. a rotary positioning mechanism; 32. a slip plate; 4. a second mounting frame; 5. a slewing bearing; 6. a support frame; 7. a clamping mechanism.

Detailed Description

The utility model is described in further detail below with reference to fig. 1-2.

Examples

The embodiment of the utility model discloses a clamp for a thin-wall cylindrical workpiece. Referring to fig. 1, the fixture mainly includes a chassis 1, a driven clamping assembly is fixedly connected to the chassis 1, and a driving clamping assembly is slidably arranged on the chassis 1.

The driving clamping assembly and the driven clamping assembly comprise a slewing bearing 5 and a clamping mechanism 7. Referring to fig. 1, the clamping mechanism 7 includes 5 pneumatic clamping claws, and the 5 pneumatic clamping claws are uniformly arranged on the surface of the slewing bearing 5 in a circumferential array.

During installation, an operator aligns one end of a workpiece with a rotary bearing 5 on a driven clamping assembly, and enables the end of the workpiece to pass through an inner ring of the rotary bearing 5, and a pneumatic clamping claw on the rotary bearing 5 automatically clamps the outer side wall of the end of the workpiece; subsequently, the operator slides the active clamping assembly in a direction approaching the driven clamping assembly, and coaxially journals the swivel bearing 5 of the active clamping assembly on the end of the workpiece remote from the driven clamping assembly, while the pneumatic clamping jaws of the active clamping assembly automatically clamp the end of the workpiece.

Because the pneumatic clamping rotation is uniformly distributed on the periphery of the workpiece in a circumferential array, the stress on the two ends of the workpiece is uniform, and the deformation of the thin-wall cylindrical workpiece caused by uneven clamping stress can be effectively reduced.

At this time, the workpiece clamping frame is arranged between the driving clamping assembly and the driven clamping assembly, and two end parts of the workpiece are exposed and are not shielded, so that a processing mechanism can be convenient for processing the two end parts of the workpiece.

In the process of clamping the workpiece, an operator can adjust the distance between the driving adjusting assembly and the driven adjusting assembly according to the actual length of the workpiece, so that the clamp is suitable for clamping workpieces with different lengths, the application range of the clamp is effectively enlarged, and the usability of the clamp is improved.

Meanwhile, as the pneumatic clamping claw can be lengthened and shortened, the clamp is applicable to clamping workpieces with different diameter sizes, the application range of the clamp is further enlarged, and the usability of the clamp is improved.

It should be noted that in some other embodiments, a different number of pneumatic clamping jaws (other types of clamping jaws, such as electric clamping jaws, etc., may be used) may be used according to the practical needs, and is not limited herein.

Referring to fig. 1, a base 2 and a second mounting frame 4 are fixedly connected to a chassis 1 through screws or welding, a first mounting frame 3 is slidably arranged on the base 2, and a supporting frame 6 is fixedly connected to the first mounting frame 3 and the second mounting frame 4 through screws.

Referring to fig. 1, a driving member 12 is fixedly connected to one end of the chassis 1, which is close to the first mounting frame 3, and a driving end of the driving member 12 is fixedly connected to the first mounting frame 3.

In this embodiment, the driving member 12 is a telescopic cylinder. Referring to the drawings, a cylinder body of a telescopic cylinder is fixed on a base frame 1 by screws or welding, and a cylinder shaft of the telescopic cylinder is fixedly connected with a first mounting frame 3 by welding. The cylinder shaft of the telescopic cylinder stretches or retracts to drive the first mounting frame 3 to slide along with the driving clamping assembly in a direction approaching or separating from the driven clamping assembly.

When a workpiece is installed, the cylinder shaft of the telescopic cylinder stretches to drive the first mounting frame 3 to slide towards the direction close to the driven clamping assembly; when the workpiece is required to be disassembled after machining, the cylinder shaft of the telescopic cylinder retracts to drive the first mounting frame 3 to slide in the direction away from the driven clamping assembly.

It should be noted that, in some other embodiments, the driving member 12 may also be an electric cylinder, which is not limited herein, while ensuring the stability and accuracy of the sliding movement of the first mounting frame 3.

Through the setting of flexible cylinder, reducible operating personnel centre gripping fixed work piece in-process, manual push-and-pull initiative clamping assembly's operation effectively promotes the convenience of operating personnel centre gripping fixed work piece.

In this embodiment, referring to fig. 1, the size of the support frame 6 is adapted to the inner ring of the revolving bearing 5, the two revolving bearings 5 are coaxially sleeved on the support frame 6, and the two revolving bearings 5 are respectively in running fit with the two support frames 6.

Through two reasonable collocations of swivel bearing 5 and support frame 6 use, can realize the installation of two swivel bearings 5, realize two swivel bearings 5 and first mounting bracket 3, second mounting bracket 4 between normal running fit's technical effect.

In actual processing, when the processing of other angles is carried out to the work piece to the needs, the operating personnel can rotate one of the slewing bearing 5 for the waiting processing position of work piece just is just opposite to processing agency, makes the operating personnel need not to adjust work piece angle after dismantling the work piece and centre gripping work piece again, effectively promotes operating personnel adjustment work piece angle in order to realize the convenience of a plurality of angle processings to the work piece.

In order to make the workpiece have the technical effect of locking after rotating for a certain angle, the condition that the workpiece shakes in the processing process is avoided, the processing accuracy is improved, and in the embodiment of the utility model, the first mounting frame 3 and the second mounting frame 4 are detachably and fixedly connected with a rotary positioning mechanism 31 through screws.

Through the setting of swivel bearing 5 for the work piece can rotate on the anchor clamps, but swivel positioning mechanism 31 locking work piece makes the relative position of work piece on the anchor clamps fixed simultaneously, makes the operating personnel adjust work piece angle after need not to dismantle the work piece and centre gripping work piece again, effectively promotes operating personnel adjustment work piece angle in order to realize the convenience of a plurality of angle processings to the work piece.

It should be noted that, the rotary positioning mechanism 31 in the present embodiment is a prior art, and is not modified in the present embodiment, and is not described herein.

Referring to fig. 1, in order to achieve the technical effect of automatically rotating a workpiece, a servo motor 11 is provided on a chassis 1. The cylinder body of the servo motor 11 is fixed on the underframe 1 through screws or welding, the driving shaft of the servo motor 11 is arranged towards the first mounting frame 3, and the driving shaft of the servo motor 11 is in transmission fit with the outer teeth of the slewing bearing 5 on the first mounting frame 3.

When the angle of the workpiece needs to be adjusted, the servo motor 11 drives the slewing bearing 5 to rotate, and as the two ends of the workpiece are clamped and fixed on the slewing bearing 5 by the pneumatic clamping claws, the servo motor 11 drives the slewing bearing 5 to rotate so as to drive the workpiece to rotate together, thereby realizing the technical effect of automatically adjusting the angle of the workpiece.

In some other embodiments, a speed reducer may be disposed between the servo motor 11 and the first mounting frame 3, so that the force application operation of the servo motor 11 to the slewing bearing 5 on the first mounting frame 3 is more stable, which is not described herein.

In order to achieve the technical effect of sliding fit between the first mounting frame 3 and the base 2, in this embodiment, two parallel mounting blocks 21 are extended and arranged on one side of the base 2 away from the chassis 1, and two sliding plates 32 are welded and fixed on the first mounting frame 3.

Referring to fig. 2, two sliding grooves 211 are formed in two opposite side walls of the two mounting blocks 21 in a penetrating manner along the axial direction, the depth and the height of the sliding grooves 211 are matched with those of the sliding plates 32, two opposite ends of the two sliding plates 32 are embedded in the two sliding grooves 211, the two sliding plates 32 are in sliding fit with the two mounting blocks 21, and the cylinder shaft of the telescopic cylinder extends or retracts to drive the first mounting frame 3 to slide on the base 2.

In some other embodiments, other structures may be adopted to achieve the technical effect of sliding fit between the first mounting frame 3 and the chassis 1, which is not described in detail herein.

The implementation principle of the clamp for the thin-wall cylindrical workpiece provided by the embodiment of the utility model is as follows: the driving clamping assembly arranged on the underframe 1 in a sliding manner is matched with the driven clamping assembly fixedly arranged on the underframe 1, so that the technical effect of clamping and fixing the outer side walls of the two ends of a workpiece is realized, the two ends of the workpiece are not shielded after the workpiece is clamped and fixed on the clamp, and the two ends of the workpiece are conveniently machined by a machining mechanism; the slewing bearing 5, the servo motor 11 and the slewing positioning mechanism 31 are matched for use, so that the technical effect of automatically adjusting the angle of the workpiece on the clamp is realized, and the convenience of adjusting the angle of the workpiece by an operator is improved; the first mounting frame 3 arranged on the underframe 1 in a sliding manner and the second mounting piece fixedly arranged on the underframe 1 are matched for use, so that the clamp can be applicable to workpieces with different length sizes when the technical effect that the driving clamping assembly is close to or far away from the driven clamping assembly can be achieved, the application range of the clamp is enlarged, and the usability of the clamp is improved.

The above embodiments are not intended to limit the scope of the present utility model, so: all equivalent changes in structure, shape and principle of the utility model should be covered in the scope of protection of the utility model.

Claims

1. The fixture for the thin-wall cylindrical workpiece is characterized by comprising a bottom frame (1), a driving clamping assembly and a driven clamping assembly, wherein the driving clamping assembly is arranged on the bottom frame (1) in a sliding manner, and the driven clamping assembly is fixedly arranged on the bottom frame (1);

the driving clamping assembly and the driven clamping assembly respectively comprise clamping mechanisms (7), and when the driving clamping assembly clamps a workpiece, the two clamping mechanisms (7) are clamped on the outer side walls of two ends of the workpiece; when the workpiece is disassembled, the two clamping mechanisms (7) are far away from the workpiece;

the driving device is characterized in that a driving piece (12) is fixedly connected to the underframe (1), the driving end of the driving piece (12) is fixedly connected with the driving clamping assembly, and the driving piece (12) drives the driving clamping assembly to slide along the direction close to or far away from the driven clamping assembly.

2. The fixture for the thin-walled cylindrical workpiece according to claim 1, wherein the clamping mechanisms (7) comprise a plurality of pneumatic clamping claws, and the pneumatic clamping claws are uniformly distributed on the circumferential sides of the two ends of the workpiece in a circumferential array;

3. The clamp for the thin-wall cylindrical workpiece according to claim 1, wherein a base (2) is fixedly connected to the underframe (1), a first mounting frame (3) is slidably arranged on the base (2), and one end, far away from the base (2), of the first mounting frame (3) is fixedly connected with the active clamping assembly;

the driving end of the driving piece (12) is fixedly connected with the first mounting frame (3), and the driving piece (12) drives the first mounting frame (3) to slide towards a direction close to or far away from the driven clamping assembly.

4. A fixture for thin-walled cylindrical workpieces according to claim 3, characterized in that two opposite mounting blocks (21) are fixedly connected to the base (2), and the two mounting blocks (21) are provided with sliding grooves (211), and the two sliding grooves (211) are opposite;

the first mounting frame (3) comprises two sliding plates (32), the opposite end parts of the sliding plates (32) are respectively embedded in the two sliding grooves (211), and the two sliding plates (32) are in sliding fit with the two mounting blocks (21).

5. The fixture for thin-walled cylindrical workpieces according to claim 4, characterized in that the driving member (12) comprises a telescopic cylinder, the cylinder body of the telescopic cylinder is fixedly connected with the chassis (1), the cylinder shaft of the telescopic cylinder is fixedly connected with the first mounting frame (3), and the telescopic cylinder drives the first mounting frame (3) to slide in a direction approaching or separating from the driven clamping assembly.

6. The fixture for the thin-wall cylindrical workpiece according to claim 5, wherein a second mounting frame (4) is fixedly connected to the bottom frame (1), and one end, far away from the bottom frame (1), of the second mounting frame (4) is fixedly connected with the driven clamping assembly.

7. The fixture for the thin-walled cylindrical workpiece according to claim 6, wherein the driving clamping assembly and the driven clamping assembly comprise a swivel bearing (5), and the two swivel bearings (5) are respectively in running fit with the first mounting frame (3) and the second mounting frame (4); the first mounting frame (3) and the second mounting frame (4) are detachably and fixedly connected with a rotary positioning mechanism (31), and the two rotary positioning mechanisms (31) control the two rotary bearings (5) to be in a rotating or locking state;

when the rotary bearings (5) drive the workpiece to rotate to a set position, the two rotary positioning mechanisms (31) lock the two rotary bearings (5), and the two rotary bearings (5) are fixed with the first mounting frame (3) and the second mounting frame (4) in relative positions.

8. The fixture for the thin-wall cylindrical workpiece according to claim 7, wherein the first mounting frame (3) and the second mounting frame (4) are fixedly connected with supporting frames (6), the two supporting frames (6) are matched with inner rings of the two slewing bearings (5), the two slewing bearings (5) are coaxially sleeved on outer side walls of the two supporting frames (6), and the two slewing bearings (5) are respectively in running fit with the two supporting frames (6).

9. The fixture for the thin-wall cylindrical workpiece according to claim 7, wherein a servo motor (11) is arranged on the underframe (1), a cylinder body of the servo motor (11) is fixedly connected with the underframe (1), a driving shaft of the servo motor (11) is arranged towards the first mounting frame (3), the driving shaft of the servo motor (11) is in transmission fit with an outer gear ring of the slewing bearing (5) on the first mounting frame (3), and the servo motor (11) drives the slewing bearing (5) to rotate.