CN115502614A

CN115502614A - Reducing flange positioning tool

Info

Publication number: CN115502614A
Application number: CN202211110451.1A
Authority: CN
Inventors: 王军; 高欣; 郑军; 李锐; 崔传宝
Original assignee: Maanshan Xinlong Special Steel Co ltd
Current assignee: Maanshan Xinlong Special Steel Co ltd
Priority date: 2022-09-13
Filing date: 2022-09-13
Publication date: 2022-12-23

Abstract

The invention discloses a variable-diameter flange positioning tool, which relates to the field of machining and comprises a base, a left frame, a right frame, a left turntable, a right turntable, a clamping assembly, a rotating device, a correcting device and a detecting assembly, wherein the left turntable is rotationally connected with the left frame, and the right turntable is rotationally connected with the right frame; the left frame and the right frame are both provided with clamping components, and the right turntable is provided with a correcting device; by arranging the clamping assembly, the centers of the two flanges can be automatically aligned after the two flanges are positioned, the correcting device can automatically correct the conical pipe, so that the conical pipe and the two flanges are concentric, the three parts are synchronously pressed and assembled, multiple positioning and clamping are not needed, and the concentricity of the three parts is improved; the locating pin and the butt joint of clamp plate locating hole can make conical duct and two flange synchronous rotations, and convenient welding sets up the determine module on right carousel, can directly carry out the measuring of gas tightness on the frock, has reduced the processing cycle of reducing flange.

Description

Reducing flange positioning tool

Technical Field

The invention relates to the field of machining, in particular to a reducing flange positioning tool.

Background

The reducing flange is an intermediate connector for connecting two different pipelines, and generally consists of a large flange, a small flange and a middle conical pipe.

The existing reducing flange needs a worker to weld one end of the conical pipe with the large flange during machining, then the other end of the conical pipe is welded with the small flange, a positioning fixture needs to be used in the welding process, the existing positioning fixture is mostly divided into two independent sets, one set is used for welding and positioning the large flange and the conical pipe, and the other set is used for welding and positioning the small flange and the conical pipe.

This results in separate welding during welding, more welding processes, and the large flange and the small flange are not concentric easily during repeated positioning, and moreover, most of the existing positioning tools are fixed in position after the flange and the conical pipe are clamped, this just makes when welding need the workman to hold welder and rotate a week around the flange and the junction of conical duct and can weld completely, when needs the robot welding, because welder's orbit is circular, this just makes the robot need constantly change welded position, and is very high to the required precision of robot, and the condition that welding skew appears easily influences welding quality.

In addition, the existing positioning and clamping does not have the function of assisting in air tightness detection, so that the air tightness of the machined variable-diameter flange is detected to be qualified by using an air tightness detection device on other stations after welding is finished, and whether an air hole exists in a welding seam is judged. This undoubtedly increases the machining cycle of the reducing flange.

Disclosure of Invention

The invention aims to provide a reducing flange positioning tool to solve the problems in the background technology.

A positioning tool for a reducing flange comprises a base, a left frame, a right frame, a left turntable, a right turntable, a clamping assembly, a rotating device, a correcting device and a detecting assembly,

the left rack slides and translates on the base through the linear module, the right rack is fixedly connected with the base, the left turntable is rotatably connected with the left rack, and the right turntable is rotatably connected with the right rack;

the clamping assembly is arranged on each of the left rack and the right rack and comprises a clamping motor and a driving pipe, an output shaft of the clamping motor is fixedly connected with a first gear, the driving pipes in the two clamping assemblies are respectively rotatably connected with the left rack and the right rack, the two driving pipes are coaxially arranged, one end of each driving pipe is fixedly connected with a second gear, the second gear is meshed with the first gear, the side wall of the right rack of the left rack is provided with four chutes, sliding blocks are connected in the chutes in a sliding mode, one ends of the sliding blocks are rotatably connected with idler wheels, the other ends of the sliding blocks are rotatably connected with pulleys, baffles are arranged on the idler wheels, the side wall of the right rack of the left rack is vertically and symmetrically and slidably connected with two limiting plates through sliding frames, limiting grooves are formed in the limiting plates, two pulleys are slidably connected in the limiting grooves, a central gear is further fixedly connected to each driving pipe, racks are respectively meshed with two sides of the central gear, and one end of each rack is fixedly connected with one limiting plate and is slidably connected with the other limiting plate;

the rotating device is used for driving the left rotating disc to rotate, and the right rotating disc is provided with a correcting device;

the correcting device is used for centering the conical pipe, the large caliber of the conical pipe faces to the left turntable, the correcting device is in butt joint with a butt joint assembly arranged on the left turntable when the left turntable moves to the right turntable and transmits the rotating force of the left turntable to the right turntable, and meanwhile, the conical pipe is automatically corrected to a position concentric with the flange;

the detection assembly is connected with the right rotary disc and used for inflating a closed space formed between the reducing flange and the left rotary disc and between the reducing flange and the right rotary disc and detecting the air tightness of the reducing flange.

Preferably, rotary device includes rotating electrical machines and pivot, rotating electrical machines and right frame fixed connection, rotating electrical machines's output shaft fixed connection gear three, the one end of pivot pass the drive tube in the left side frame and with left carousel fixed connection, and its other end fixedly connected with gear four, gear three and gear four mesh.

Preferably, correcting unit includes back shaft and supporting seat, the right-hand member and the right turn plate fixed connection of back shaft, and its left end sliding connection has hinge cover one, it is two to go back fixedly connected with hinge cover on the back shaft, hinge cover one is located the left side of hinge cover two, the supporting seat is equipped with four round the circumference equidistance of back shaft, can dismantle through the screw on the supporting seat and be connected with the profile modeling supporting shoe, the bottom of supporting seat articulates there are two bracing pieces, and one of them bracing piece is articulated with hinge cover two, and another bracing piece is articulated with hinge cover one, the cover is equipped with spring one on hinge cover two and the back shaft between the hinge cover one.

Preferably, a spline is arranged on the first hinge sleeve, a spline groove is formed in the support shaft, a pressing plate is arranged at the left end of the first hinge sleeve, a positioning hole is formed in the pressing plate, and sealing gaskets are arranged on the left rotary table and the right rotary table.

Preferably, the detection assembly includes the trachea, tracheal one end and the center department fixed connection of right carousel, and its other end passes the drive tube in the frame of the right side to be connected with rotary joint, rotary joint and gas tightness detection device are connected, be equipped with a plurality of gas ports that communicate with the trachea on the carousel of the right side.

Preferably, be equipped with two butt joint subassemblies that correspond with the locating hole in the left turn table, the butt joint subassembly includes the shell body, sliding connection has the locating pin in the shell body, be equipped with spring two between the interior bottom of locating pin and shell body, the tip of locating pin is equipped with the ball.

The invention has the advantages that:

by arranging the clamping assembly, the centers of the two flanges can be automatically aligned after the two flanges are positioned, the conical pipe is sleeved on the correcting device, and the correcting device can automatically correct the conical pipe when the left rack is close to the right rack, so that the conical pipe and the two flanges are concentric, the three parts are tightly pressed and assembled, multiple positioning and clamping are not needed, and the concentricity of the three parts is improved;

the positioning pin on the left turntable is in butt joint with the positioning hole of the pressure plate, so that the left turntable and the right turntable can synchronously rotate, the conical pipe is driven to synchronously rotate with the two flanges, the welding work of the large flange and the conical pipe and the welding work of the small flange and the conical pipe can be simultaneously finished under the condition that the position of the welding gun is not changed, the welding gun does not need to adjust the position every time, and the welding precision is high;

the air pipe is arranged on the right rotary table, so that air can be filled into a closed space formed between the reducing flange and the left rotary table and between the reducing flange and the right rotary table, the air tightness can be directly detected on the tool after the welding is completed, an additional detection station does not need to be added, and the processing period of the reducing flange is greatly shortened.

Drawings

FIG. 1 is an isometric view of the present invention;

FIG. 2 is a side view of the present invention;

FIG. 3 is a cross-sectional view of the present invention after clamping is complete;

FIG. 4 is an enlarged view of a portion of FIG. 3 at A;

FIG. 5 is a schematic view of the upper part of the left frame with the clamping device;

fig. 6 is a schematic diagram of the structures on the right frame.

FIG. 7 is a schematic structural diagram of a variable diameter flange.

In the figure: 1. a base; 2. a left frame; 3. a right frame; 4. a left turn plate; 5. a right turntable;

6. clamping the assembly; 60. clamping the motor; 61. a drive tube; 62. a first gear; 63. a second gear; 64. a slider; 65. a chute; 641. a roller; 642 pulleys; 643. a baffle plate; 65. a limiting plate; 651. a limiting groove; 66. a sun gear; 67. a rack; 68. a carriage;

7. a rotating device; 71. a rotating electric machine; 72. a rotating shaft; 73. a third gear; 74. a fourth gear;

8. a correcting device; 80. a support shaft; 81. a supporting base; 82. a first hinge sleeve; 83. pressing a plate; 84. positioning holes; 85. a second hinge sleeve; 86. a profiling support block; 87. a support bar; 88. a first spring;

9. a detection component; 91. an air tube; 92. a rotary joint;

10. a docking assembly; 101. an outer housing; 102. positioning pins; 103. a second spring; 11. a linear module; 12. A gasket; 13. a tapered tube; 14. a large flange; 15. a small flange.

Detailed Description

In order to make the technical means, the creation characteristics, the achievement purposes and the effects of the invention easy to understand, the invention is further described with the specific embodiments.

As shown in fig. 1 to 7, a positioning tool for a reducing flange comprises a base 1, a left frame 2, a right frame 3, a left rotary disc 4, a right rotary disc 5, a clamping assembly 6, a rotating device 7, a correcting device 8 and a detecting assembly 9,

the left rack 2 slides and translates on the base 1 through the linear module 11, the right rack 3 is fixedly connected with the base 1, the left rotating disc 4 is rotatably connected with the left rack 2, and the right rotating disc 5 is rotatably connected with the right rack 3;

all be equipped with clamping subassembly 6 on left side frame 2 and the right side frame 3, clamping subassembly 6 includes clamping motor 60 and driving tube 61, the output shaft fixedly connected with gear 62 of clamping motor 60, driving tube 61 in two clamping subassemblies 6 rotates with left side frame 2 and right side frame 3 respectively and is connected, two coaxial settings of driving tube 61, the one end fixedly connected with gear two 63 of driving tube 61, gear two 63 and the meshing of gear 62, left side frame 2 has the lateral wall of right side frame 3 all to be equipped with four spout 65, sliding connection has slider 64 in the spout 65, the one end of slider 64 is rotated and is connected with the gyro wheel 641 other end and rotates and be connected with pulley 642, gyro wheel 641 can rotate along with the flange, make the flange can rotate smoothly, be equipped with baffle 643 on the gyro wheel 641, baffle 643 plays the effect that blocks the flange, avoid the flange landing.

The side wall of the right rack 3 of the left rack 2 is vertically and symmetrically connected with two limit plates 65 in a sliding manner through a sliding frame 68, the limit plates 65 are provided with limit grooves 651, two pulleys 642 are connected in the limit grooves 651 in the sliding manner, a central gear 66 is also fixedly connected to the driving pipe 61, two sides of the central gear 66 are respectively engaged with a rack 67, and one end of each rack 67 is fixedly connected with one limit plate 65 and is connected with the other limit plate 65 in a sliding manner;

the rotating device 7 is used for driving the left turntable 4 to rotate, and the right turntable 5 is provided with a correcting device 8;

the correcting device 8 is used for centering the conical pipe 13, the conical pipe 13 is sleeved on the outer side of the correcting device 8, the conical pipe 13 is large in caliber and faces towards the left rotary table 4, the correcting device 8 is in butt joint with a butt joint assembly 10 arranged on the left rotary table 4 when the left rotary table 4 moves towards the right rotary table 5, the rotating force of the left rotary table 4 is transmitted to the right rotary table 5, and meanwhile, the conical pipe 13 is automatically corrected to be concentric with the flange;

the detection assembly 9 is connected with the right rotary disc 5 and used for inflating a closed space formed between the reducing flange and the left rotary disc 4 and the right rotary disc 5 and detecting the air tightness of the reducing flange.

In this embodiment, the rotating device 7 includes a rotating motor 71 and a rotating shaft 72, the rotating motor 71 is fixedly connected with the right frame 3, an output shaft of the rotating motor 71 is fixedly connected with a gear three 73, one end of the rotating shaft 72 passes through the driving pipe 61 on the left frame 2 and is fixedly connected with the left rotating disk 4, and the other end of the rotating shaft is fixedly connected with a gear four 74, and the gear three 73 is meshed with the gear four 74.

In this embodiment, the correcting device 8 includes a supporting shaft 80 and a supporting seat 81, the right end of the supporting shaft 80 is fixedly connected with the right turn plate 5, the left end of the supporting shaft is slidably connected with a first hinge sleeve 82, a second hinge sleeve 85 is fixedly connected to the supporting shaft 80, the first hinge sleeve 82 is located on the left side of the second hinge sleeve 85, four supporting seats 81 are arranged around the supporting shaft 80 at equal intervals in the circumferential direction, a profiling supporting block 86 is detachably connected to the supporting seat 81 through a screw, the profiling tapered tube 13 is detachably connected to the supporting seat 81 through a screw, and different profiling supporting blocks 86 can be conveniently replaced to adapt to tapered tubes 13 with different tapers. The bottom of the supporting seat 81 is hinged with two supporting rods 87, one supporting rod 87 is hinged with the second hinge sleeve 85, the other supporting rod 87 is hinged with the first hinge sleeve 82, and a first spring 88 is sleeved on the supporting shaft 80 between the second hinge sleeve 85 and the first hinge sleeve 82.

In this embodiment, a spline is disposed on the first hinge sleeve 82, a spline groove sliding with the spline is disposed on the support shaft 80, the first hinge sleeve 82 and the support shaft 80 slide through the spline and the spline groove, and the first hinge sleeve 82 is kept to slide on the support shaft 80, and the pressing plate 83 rotates to drive the support shaft 80 through the first hinge sleeve 82, so as to drive the left turntable 4 to rotate synchronously. The left end of the first hinge sleeve 82 is provided with a pressing plate 83, the pressing plate 83 is provided with a positioning hole 84, and the left rotating disk 4 and the right rotating disk 5 are both provided with sealing gaskets 12. The sealing gaskets 12 can seal the large flange 14 with the left turn plate 4 and the small flange 15 with the right turn plate 5.

In this embodiment, two docking assemblies 10 corresponding to the positioning holes 84 are disposed in the left turn plate 4, each docking assembly 10 includes an outer shell 101, a positioning pin 102 is slidably connected in the outer shell 101, a second spring 103 is disposed between the positioning pin 102 and the inner bottom of the outer shell 101, and a ball is disposed at an end of the positioning pin 102. The balls serve to reduce friction.

In this embodiment, the detecting assembly 9 includes an air tube 91, one end of the air tube 91 is fixedly connected to the center of the right turn plate 5, and the other end thereof passes through the driving tube 61 on the right frame 3 and is connected to a rotary joint 92, the rotary joint 92 is connected to the air tightness detecting device, and the rotary joint 92 is used for maintaining communication with the air tightness detecting device when the air tube 91 rotates. The right rotary disc 5 is provided with a plurality of air ports communicated with the air pipe 91. A certain amount of gas is filled, the air pressure in a closed space formed between the reducing flange and the left rotary disc 4 and between the reducing flange and the right rotary disc 5 is observed by using an air tightness detection device to judge whether the air pressure is changed or not, if the air pressure is reduced, the air tightness is judged to be unqualified, the situation that air leaks at a welding seam is possible, and the unqualified reducing flange is timely sorted out.

The working process and the principle thereof are as follows:

the reducing flange is composed of a large flange 15, a conical pipe 13 and a small flange 14, when the tool is used, the large flange 14 is firstly placed between four rollers 641 of the left rack 2, the small flange 15 is placed between four rollers 641 of the right rack 3, and the four rollers 641 form a square.

The clamping motor 60 is started, the driving pipe 61 is driven to rotate through the first gear 62 and the second gear 63, the driving pipe 61 drives the central gear 66 to rotate, the rack 67 is meshed with the central gear 66, the rack 67 moves close to each other at the moment, so that the two limit plates 65 are close to each other under the limiting sliding action of the sliding frame 68, when the limit plates 65 are close to each other, the limit grooves 651 have downward force on the pulleys 642, and the sliders 64 can only slide in the sliding grooves 65, so that the pulleys 642 in the same limit grooves 651 are close to each other at the moment, the four sliders 64 move towards the center synchronously, finally the flanges are clamped by the rollers 641, the circle centers of the flanges are preliminarily fixed, and as the rollers 641 are only in tangent plane contact with the flanges, the friction force is not enough to limit the axial movement of the flanges, and the baffles 643 are arranged on the rollers 641 and play a role of the flanges to avoid the flanges from sliding off.

After the circle centers of the two flanges are determined in the same manner, the conical tube 13 is sleeved on the outer side of the correcting device 8 in a state that the small opening faces the right turntable 5, and then the left frame 2 is driven to move linearly towards the right frame 3 by the linear module 11.

When the left frame 2 translates, the rotating motor 71 is started to drive the rotating shaft 72 to rotate through the third gear 73 and the fourth gear 74, the rotating shaft 72 rotates and is fixed with the left rotating disc 4, so the left rotating disc 4 can rotate slowly, the rotating speed of the rotating disc is the integral rotating speed of the flange and the conical tube 13 during welding, when the rotating disc contacts with the pressing plate 83, the positioning pin 102 abuts against the pressing plate 83, the second spring 103 is compressed, the ball at the end part of the positioning pin 102 plays a role in reducing friction, and the positioning pin 102 rotating along with the rotating disc is inserted into the positioning hole 84 to realize butt joint.

The first hinge sleeve 82 and the support shaft 80 slide through splines and spline grooves, and the pressing plate 83 can rotate to drive the support shaft 80 through the first hinge sleeve 82 so as to drive the left turntable 4 to synchronously rotate.

Meanwhile, with the continuous approach of the right rotary disc 5, the first spring 88 is compressed, the first hinge sleeve 82 slides rightwards on the support shaft 80, the distance between the first hinge sleeve 82 and the second hinge sleeve 85 is reduced, the support rod 87 continuously pushes the support seat 81 outwards to expand, and when the tapered tube 13 is supported in the contact between the profiling support block 86 and the tapered tube 13, the tapered tube 13 is concentric with the two flanges. The profiling tapered tube 13 is detachably connected with the supporting seat 81 by adopting a screw, so that different profiling supporting blocks 86 can be conveniently replaced to adapt to tapered tubes 13 with different tapers.

The end face of the conical pipe 13 is just pressed between the two flanges, the other end faces of the two flanges are respectively attached to the left rotating disk 4 and the right rotating disk 5, and the sealing gasket 12 can seal the large flange 14, the left rotating disk 4 and the small flange 15 with the right rotating disk 5.

At this moment, the left rotating disc 4 and the right rotating disc 5 can drive the conical pipe 13 and the two flanges to synchronously rotate when rotating, the roller 641 also rotates in the process, so that the flanges can normally rotate, the welding gun can simultaneously weld the large flange 14 and the conical pipe 13 as well as the small flange 15 and the conical pipe 13, the position of the welding gun can be unchanged, and the error of the welding position is reduced.

After welding, a certain amount of gas is filled into the sealed space formed between the reducing flange and the left and right turnplates 4 and 5 through the gas pipe 91, and whether the gas pressure changes is observed by using a gas tightness detecting device, which is not shown in the figure, wherein the rotary joint 92 is used for keeping communication with the gas tightness detecting device when the gas pipe 91 rotates.

If the air pressure is reduced, air leakage occurs, the air tightness is judged to be unqualified, and the situation that air leakage exists at the welding seam can be possibly caused, so that unqualified reducing flanges are timely sorted out on the same tool. It is not necessary to equip a separate airtightness detection tool.

It will be appreciated by those skilled in the art that the invention may be embodied in other specific forms without departing from the spirit or essential characteristics thereof. The embodiments disclosed above are therefore to be considered in all respects as illustrative and not restrictive. All changes which come within the scope of or equivalence to the invention are intended to be embraced therein.

Claims

1. A positioning tool for a reducing flange is characterized by comprising a base (1), a left frame (2), a right frame (3), a left turntable (4), a right turntable (5), a clamping assembly (6), a rotating device (7), a correcting device (8) and a detecting assembly (9),

the left rack (2) slides and translates on the base (1) through the linear module (11), the right rack (3) is fixedly connected with the base (1), the left turntable (4) is rotatably connected with the left rack (2), and the right turntable (5) is rotatably connected with the right rack (3);

the clamping device is characterized in that clamping components (6) are arranged on the left rack (2) and the right rack (3), each clamping component (6) comprises a clamping motor (60) and a driving pipe (61), a first gear (62) is fixedly connected to an output shaft of the clamping motor (60), the driving pipes (61) in the two clamping components (6) are rotatably connected with the left rack (2) and the right rack (3) respectively, the two driving pipes (61) are coaxially arranged, a second gear (63) is fixedly connected to one end of each driving pipe (61), the second gear (63) is meshed with the first gear (62), four sliding grooves (65) are arranged on the side wall of the right rack (3) of the left rack (2), sliding blocks (64) are slidably connected in the sliding grooves (65), a roller (641) is rotatably connected to one end of each sliding block (64), a pulley (642) is rotatably connected to the other end of each sliding block, a baffle (643) is arranged on each roller (641), two limiting plates (66) are slidably connected to the side wall of the right rack (3) through a sliding frame (68), and two limiting plates (642) are further connected with a limiting plate (66) through a sliding block (65) and a limiting plate (651) and a limiting groove (642) in a limiting groove (66) in a sliding groove (642) is connected in a sliding block in a sliding way, racks (67) are meshed with two sides of the central gear (66), and one end of each rack (67) is fixedly connected with one limiting plate (65) and is connected with the other limiting plate (65) in a sliding manner;

the rotating device (7) is used for driving the left turntable (4) to rotate, and the right turntable (5) is provided with a correcting device (8);

the correcting device (8) is used for centering the conical pipe (13), the large caliber of the conical pipe (13) faces to the left rotary table (4), the correcting device (8) is in butt joint with a butt joint assembly (10) arranged on the left rotary table (4) when the left rotary table (4) moves to the right rotary table (5), the rotating force of the left rotary table (4) is transmitted to the right rotary table (5), and meanwhile the conical pipe (13) is automatically corrected to be concentric with the flange;

the detection assembly (9) is connected with the right turntable (5) and used for inflating a closed space formed between the reducing flange and the left turntable (4) and the right turntable (5) and detecting the air tightness of the reducing flange.

2. The variable diameter flange positioning tool according to claim 1, wherein the rotating device (7) comprises a rotating motor (71) and a rotating shaft (72), the rotating motor (71) is fixedly connected with the right frame (3), an output shaft of the rotating motor (71) is fixedly connected with a gear three (73), one end of the rotating shaft (72) penetrates through a driving pipe (61) on the left frame (2) and is fixedly connected with the left rotating disc (4), the other end of the rotating shaft is fixedly connected with a gear four (74), and the gear three (73) is meshed with the gear four (74).

3. The variable diameter flange positioning tool according to claim 1, wherein the correcting device (8) comprises a supporting shaft (80) and a supporting seat (81), the right end of the supporting shaft (80) is fixedly connected with the right turntable (5), the left end of the supporting shaft is slidably connected with a first hinge sleeve (82), a second hinge sleeve (85) is further fixedly connected to the supporting shaft (80), the first hinge sleeve (82) is located on the left side of the second hinge sleeve (85), four supporting seats (81) are arranged around the supporting shaft (80) at equal intervals in the circumferential direction, a profiling supporting block (86) is detachably connected to the supporting seat (81) through screws, two supporting rods (87) are hinged to the bottom of the supporting seat (81), one of the supporting rods (87) is hinged to the second hinge sleeve (85), the other supporting rod (87) is hinged to the first hinge sleeve (82), and a first spring (88) is sleeved on the supporting shaft (80) between the second hinge sleeve (85) and the first hinge sleeve (82).

4. The variable diameter flange positioning tool according to claim 3, wherein a spline is arranged on the first hinge sleeve (82), a spline groove is arranged on the support shaft (80), a pressing plate (83) is arranged at the left end of the first hinge sleeve (82), a positioning hole (84) is formed in the pressing plate (83), and sealing gaskets (12) are arranged on the left rotating disc (4) and the right rotating disc (5).

5. The reducing flange positioning tool according to claim 1, wherein the detection assembly (9) comprises an air pipe (91), one end of the air pipe (91) is fixedly connected with the center of the right turntable (5), the other end of the air pipe penetrates through a driving pipe (61) on the right rack (3) and is connected with a rotary joint (92), the rotary joint (92) is connected with an air tightness detection device, and a plurality of air ports communicated with the air pipe (91) are formed in the right turntable (5).

6. The variable-diameter flange positioning tool according to claim 1, wherein two butt joint assemblies (10) corresponding to the positioning holes (84) are arranged in the left turntable (4), each butt joint assembly (10) comprises an outer shell (101), a positioning pin (102) is connected in the outer shell (101) in a sliding mode, a second spring (103) is arranged between the positioning pin (102) and the inner bottom of the outer shell (101), and balls are arranged at the end portions of the positioning pins (102).