Forging machine with safeguarding mechanism

Abstract

The application belongs to the technical field of forging machine tools, and particularly relates to a forging machine tool with a protection mechanism, which comprises a machine tool body, a positioning assembly arranged on the machine tool body, an air curtain protection mechanism and a telescopic shield mechanism, the air curtain protection mechanism is arranged on the machine tool body, and the telescopic shield mechanism is arranged on the machine tool body; the air curtain protection mechanism comprises a forging and pressing assembly, a high-speed thin airflow layer assembly and a metal collecting assembly, the forging and pressing assembly is arranged on the air curtain protection mechanism, the high-speed thin airflow layer assembly is arranged on the air curtain protection mechanism, and the metal collecting assembly is arranged on the air curtain protection mechanism; through the arrangement of the air curtain protection mechanism, the high-speed thin airflow layer forms an air wall around the metal blank, can block the direct diffusion of high-temperature smoke and hot flow to the operation area, and improves the safety of personnel.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of forging machine tools, and particularly relates to a forging machine tool with a protection mechanism. BACKGROUND

[0002] The forging machine tool is a collective term of processing equipment for obtaining required shapes, sizes and performances by using impact force or pressure to make metal produce plastic deformation between upper and lower anvil irons, and is widely applied to many fields such as automobiles, aerospace, mechanical manufacturing and the like, and plays a key role in improving the strength and performance of metal parts.

[0003] However, the current forging machine tool has many safety hazards and environmental pollution problems in the actual processing process. When forging, the forged piece is subjected to high-energy impact, and the internal stress distribution is uneven, which is easy to cause the forged piece to crack, and the metal debris generated by the cracking can splash at high speed, posing a serious threat to the personal safety of the operator. At the same time, the metal surface scale falls off during the forging process, which releases a large amount of scale dust, which diffuses in the air, not only pollutes the working environment, but also may be inhaled by the operator, endangering the health. In addition, the high temperature generated by forging can heat the surrounding air, forming smoke, further deteriorating the working environment. Moreover, the forging machine tool needs to use lubricating oil during operation, and the lubricating oil volatilizes in the high-temperature environment, which produces oil mist and harmful gas, not only affecting the air quality, but also long-term contact may cause respiratory diseases and other health problems of the operator. SUMMARY

[0004] In order to solve the above problems, the application provides a forging machine tool with a protection mechanism.

[0005] The technical scheme adopted by the application is as follows: the application provides a forging machine tool with a protection mechanism, which comprises a machine tool body, a positioning assembly arranged on the machine tool body, an air curtain protection mechanism arranged on the machine tool body, and a telescopic shield mechanism arranged on the machine tool body.

[0006] Further, the machine tool body comprises a machine tool lower cavity, a machine tool frame is arranged on the machine tool lower cavity, and an equipment cavity is arranged at the top of the inside of the machine tool frame.

[0007] Further, the forging assembly comprises a load-bearing base arranged in the lower cavity of the machine tool, a hydraulic cylinder mounted in the equipment cavity, an output end of the hydraulic cylinder connected to a hydraulic hammer body, a square frame-shaped air inlet groove formed at the top end of the lower cavity of the machine tool, and the square frame-shaped air inlet groove and the lower cavity fixedly connected through a connecting rib.

[0008] Further, the high-speed thin air flow layer assembly comprises a square frame, the square frame is installed at the lower end of the equipment cavity, four long air outlet slits are formed at the lower end of the square frame, one end of a metal connecting pipe is connected through the outer side wall of the square frame, the other end of the metal connecting pipe is connected through one end of a connecting hose, the other end of the connecting hose is mounted at the output end of a high-pressure air blower, and the air suction end of the high-pressure air blower is connected through the lower end of the outer side wall of the lower cavity of the machine tool.

[0009] Further, the metal collection assembly comprises a water tank, the inside bottom end of the lower cavity of the machine tool is provided with a water tank, a magnet is arranged on the inside bottom wall of the water tank, a metal mesh cage is fixedly connected to the inner side wall of the lower cavity of the machine tool, and activated carbon is arranged in the metal mesh cage.

[0010] Further, the telescopic shield mechanism comprises a trigger assembly and a telescopic partial protection assembly.

[0011] Further, the trigger assembly comprises a groove arranged at the inside top end of the load-bearing base, one end of a first spring is fixedly connected to the inside bottom end of the groove, the other end of the first spring is fixedly connected to a pressing plate, the pressing plate is fixedly sleeved with a first connecting pipe, a cavity is fixedly connected to the lower end of the groove, a first limiting plate is fixedly connected to the inner side wall of the groove, the first limiting plate is arranged above the pressing plate, a base disc is fixedly connected to the top end of the first connecting pipe, a first piston is fixedly connected to the bottom end of the first connecting pipe, the first piston is slidingly arranged in the cavity, and the first connecting pipe is slidingly sleeved on the first limiting plate.

[0012] Further, the telescopic partial protection assembly comprises a storage cavity arranged at the inside top end of the load-bearing base, a push cavity is connected through the lower end of the storage cavity, one end of a second connecting pipe is connected through the lower end of the outer side wall of the cavity, the other end of the second connecting pipe is connected through the lower end of the push cavity, a second piston is slidingly arranged in the push cavity, a connecting rod is fixedly connected to the upper end of the second piston, a push plate is fixedly connected to the upper end of the connecting rod, a second limiting plate is fixedly connected to the inner side wall of the push cavity, the connecting rod is slidingly arranged in the second limiting plate, the push plate is arranged in the storage cavity, a baffle is fixedly connected to the top end of the push plate, one end of a second spring is fixedly connected to the top end of the push plate, and the other end of the second spring is fixedly connected to the inside top end of the storage cavity.

[0013] Further, the second connecting pipe and the cavity are provided with hydraulic oil, and the hydraulic oil is arranged below the cavity.

[0014] Further, the positioning assembly comprises a telescopic air cylinder arranged in the machine tool frame, an output end of the telescopic air cylinder is fixedly connected with a clamping pipe, an outer end of the clamping pipe is fixedly connected with a motor, an output end of the motor is fixedly connected with a first lead screw, one end of the first lead screw is fixedly connected with one end of a second lead screw, the other end of the second lead screw is rotatably connected with an inner end of the clamping pipe, a first sleeve pipe is sleeved on the first lead screw, the first lead screw and the first sleeve pipe are threadedly connected, a second sleeve pipe is sleeved on the second lead screw, the second lead screw and the second sleeve pipe are threadedly connected, the first sleeve pipe and the second sleeve pipe are the same in structure, one side of the first sleeve pipe is fixedly connected with a first clamping plate, one side of the second sleeve pipe is fixedly connected with a second clamping plate, and the threads of the first lead screw and the second lead screw are opposite.

[0015] The application has the following beneficial effects by adopting the above structure:

[0016] (1) The air curtain protection mechanism is arranged, a high-speed thin air flow layer forms an "air wall" around the metal blank, which can block the direct diffusion of high-temperature smoke and heat flow to the operation area, and improve the safety of personnel.

[0017] (2) The air curtain protection mechanism is arranged to block the diffusion of smoke and heat flow during the forging and pressing of the metal blank, and to release the oxide scale dust, high-temperature smoke, and oil mist and harmful gases generated by the volatilization of lubricating oil during the forging process. The air curtain guides large debris to fall into the collection groove along the specified direction, and blocks the diffusion of dust outward.

[0018] (3) The variable guard mechanism is arranged to block the metal blank around to prevent sparks, metal slag, burns, or ignition of combustible materials.

[0019] (4) The baffle is automatically raised during forging to physically block metal slag and sparks, and to avoid burning operators or igniting combustible materials.

[0020] (5) The circulating air flow design of the air curtain + square frame type air inlet groove guides the oxide scale dust and high-temperature smoke to the lower cavity to prevent leakage, improves the air quality in the workshop, and the activated carbon can adsorb organic gases (VOCs) and part of the odor formed by the evaporation of lubricating oil, improve the working environment, and the water pool cools and captures the high-temperature particles that fall off to avoid bouncing and splashing again, and improves the cleanliness and safety. BRIEF DESCRIPTION OF DRAWINGS

[0021] In order to more clearly illustrate the technical solutions of the present application, the drawings required to be used in the description will be briefly introduced as follows. Obviously, the drawings in the following description are only some embodiments of the present application, and other drawings can also be obtained by those skilled in the art without any creative effort on the basis of these drawings.

[0022] Figure 1 Front view of the forging machine tool with protection mechanism of the present application;

[0023] Figure 2 Structure schematic diagram of the forging machine tool with protection mechanism of the present application;

[0024] Figure 3 Structure schematic diagram of the telescopic shield mechanism;

[0025] Figure 4 Left view structure schematic diagram of the telescopic partial protection assembly;

[0026] Figure 5 Plan view of the lower cavity of the machine tool;

[0027] Figure 6 Structure schematic diagram of the positioning assembly;

[0028] Figure 7 Bottom view of the square frame;

[0029] Figure 8 Figure 2 Partial enlarged view of part A.

[0030] 1, machine tool body, 2, air curtain protection mechanism, 3, telescopic shield mechanism, 4, positioning assembly, 5, motor, 6, equipment cavity, 7, machine tool frame, 8, lower cavity of the machine tool, 9, forging and pressing assembly, 10, high-speed thin air flow layer assembly, 11, metal collection assembly, 12, load-bearing base, 13, square frame air inlet groove, 14, connecting rib, 15, hydraulic hammer body, 16, hydraulic cylinder, 17, square frame, 18, long air outlet slot, 19, high-pressure air blower, 20, metal connecting pipe, 21, connecting hose, 22, water tank, 23, magnet, 24, metal mesh cage, 25, activated carbon, 26, trigger assembly, 27, telescopic partial protection assembly, 28, base disc, 29, first connecting pipe, 30, groove, 31, first limiting plate, 32, pressing plate, 33, first spring, 34, first piston, 35, cavity, 36, baffle, 37, push plate, 38, second spring, 39, second limiting plate, 40, second piston, 41, second connecting pipe, 42, storage cavity, 43, push cavity, 44, telescopic air cylinder, 45, clamping pipe, 46, first lead screw, 47, second lead screw, 48, first sleeve, 49, second sleeve, 50, first clamping plate, 51, second clamping plate, 52, connecting rod. ​DETAILED DESCRIPTION

[0031] In order to make the objectives, characteristics and advantages of the present application more obvious and easy to understand, the technical solutions in the present application will be clearly and completely described below in combination with the drawings in the specific embodiments. Obviously, the following described embodiments are only some of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative labor fall within the scope of protection of the present application.

[0032] As shown in Figures 1-8 The present application provides a forging machine with a protection mechanism, which comprises a machine body 1, a positioning assembly 4 arranged on the machine body 1, an air curtain protection mechanism 2 arranged on the machine body 1, and a telescopic shield mechanism 3 arranged on the machine body 1. The air curtain protection mechanism 2 comprises a forging assembly 9, a high-speed thin airflow layer assembly 10, and a metal collection assembly 11.

[0033] The machine body 1 comprises an equipment cavity 6, a machine frame 7, and a machine lower cavity 8. The machine lower cavity 8 is provided with the machine frame 7, and the inside top end of the machine frame 7 is provided with the equipment cavity 6.

[0034] The forging assembly 9 comprises a bearing base 12, a square frame air inlet groove 13, a connecting rib 14, a hydraulic hammer body 15, and a hydraulic cylinder 16. The bearing base 12 is arranged in the machine lower cavity 8, the hydraulic cylinder 16 is arranged in the equipment cavity 6, the output end of the hydraulic cylinder 16 is connected with the hydraulic hammer body 15, the square frame air inlet groove 13 is arranged at the top end of the machine lower cavity 8, and the square frame air inlet groove 13 and the machine lower cavity 8 are fixedly connected through the connecting rib 14.

[0035] The high-speed thin airflow layer assembly 10 comprises a square frame 17, a long strip air outlet slot 18, a high-pressure air blower 19, a metal connecting pipe 20, and a connecting hose 21. The square frame 17 is arranged at the lower end of the equipment cavity 6, four long strip air outlet slots 18 are arranged at the lower end of the square frame 17, one end of the metal connecting pipe 20 is connected through the outer side wall of the square frame 17, the other end of the metal connecting pipe 20 is connected with one end of the connecting hose 21, the other end of the connecting hose 21 is arranged at the output end of the high-pressure air blower 19, and the air suction end of the high-pressure air blower 19 is connected through the lower end of the outer side wall of the machine lower cavity 8.

[0036] The metal collecting assembly 11 comprises a water pool 22, a magnet 23, a metal mesh cage 24 and activated carbon 25, the water pool 22 is arranged at the inner bottom end of the machine tool lower cavity 8, the magnet 23 is arranged on the inner bottom wall of the water pool 22, the metal mesh cage 24 is fixedly connected to the inner side wall of the machine tool lower cavity 8, and the activated carbon 25 is arranged in the metal mesh cage 24.

[0037] The telescopic shield mechanism 3 comprises a trigger assembly 26 and a telescopic partial protection assembly 27.

[0038] The trigger assembly 26 comprises a base disc 28, a first connecting pipe 29, a groove 30, a first limiting plate 31, a pressing plate 32, a first spring 33, a first piston 34 and a cavity 35, the groove 30 is arranged at the inner top end of the load-bearing base 12, one end of the first spring 33 is fixedly connected to the inner bottom end of the groove 30, the other end of the first spring 33 is fixedly connected to the pressing plate 32, the pressing plate 32 is fixedly sleeved with the first connecting pipe 29, the lower end of the groove 30 is fixedly connected to the cavity 35, the first limiting plate 31 is fixedly connected to the inner side wall of the groove 30 and arranged above the pressing plate 32, the top end of the first connecting pipe 29 is fixedly connected to the base disc 28, the bottom end of the first connecting pipe 29 is fixedly connected to the first piston 34, the first piston 34 is slidingly arranged in the cavity 35, and the first connecting pipe 29 is slidingly sleeved on the first limiting plate 31.

[0039] The telescopic partial protection assembly 27 comprises a baffle 36, a push plate 37, a second spring 38, a second limiting plate 39, a second piston 40, a second connecting pipe 41, a storage cavity 42, a pushing cavity 43 and a connecting rod 52, the storage cavity 42 is arranged at the inner top end of the load-bearing base 12, the lower end of the storage cavity 42 is throughly connected to the pushing cavity 43, the lower end of the outer side wall of the cavity 35 is throughly connected to one end of the second connecting pipe 41, the other end of the second connecting pipe 41 is throughly connected to the lower end of the pushing cavity 43, the second piston 40 is slidingly arranged in the pushing cavity 43, the upper end of the second piston 40 is fixedly connected to the connecting rod 52, the upper end of the connecting rod 52 is fixedly connected to the push plate 37, the inner side wall of the pushing cavity 43 is fixedly connected to the second limiting plate 39, the connecting rod 52 is slidingly arranged in the second limiting plate 39, the push plate 37 is arranged in the storage cavity 42, the top end of the push plate 37 is fixedly connected to the baffle 36, the top end of the push plate 37 is fixedly connected to one end of the second spring 38, and the other end of the second spring 38 is fixedly connected to the inner top end of the storage cavity 42.

[0040] The second connecting pipe 41 and the cavity 35 are provided with hydraulic oil, and the hydraulic oil is arranged below the cavity 35.

[0041] The positioning assembly 4 comprises a telescopic air cylinder 44, a clamping pipe 45, a first lead screw 46, a second lead screw 47, a first sleeve 48, a second sleeve 49, a first clamping plate 50, a second clamping plate 51 and a motor 5, the telescopic air cylinder 44 is arranged in the machine tool frame 7, the output end of the telescopic air cylinder 44 is fixedly connected with the clamping pipe 45, the outer end of the clamping pipe 45 is fixedly connected with the motor 5, the output end of the motor 5 is fixedly connected with the first lead screw 46, one end of the first lead screw 46 is fixedly connected with one end of the second lead screw 47, the other end of the second lead screw 47 is rotatably connected with the inner end of the clamping pipe 45, the first lead screw 46 is sleeved with the first sleeve 48, the first lead screw 46 and the first sleeve 48 are threadedly connected, the second lead screw 47 is sleeved with the second sleeve 49, the second lead screw 47 and the second sleeve 49 are threadedly connected, the first sleeve 48 and the second sleeve 49 are the same in structure, one side of the first sleeve 48 is fixedly connected with the first clamping plate 50, one side of the second sleeve 49 is fixedly connected with the second clamping plate 51, the threads of the first lead screw 46 and the second lead screw 47 are opposite.

[0042] In specific use, during forging, the heated metal blank is placed on the base plate 28 by the clamp, the high-pressure air blower 19 is started, the high-pressure air blower 19 draws air from the lower cavity 8 of the machine tool, enters the square frame 17 through the connecting hose 21 and the metal connecting pipe 20, and finally blows to the square frame air inlet groove 13 through the long air outlet slot 18, enters the lower cavity 8 of the machine tool, and forms a high-speed thin air flow layer around the metal blank, which is used to block the diffusion of smoke and heat flow during the forging of the metal blank, and release the oxide scale dust, high-temperature smoke, if the lubricating oil volatilizes, oil mist and harmful gas will also be generated, the air curtain guides the larger debris to fall into the collecting groove along the specified direction, while blocking the diffusion of dust outward, the water pool 22 prevents the secondary splashing of high-temperature particles, the magnet 23 is used to adsorb high-temperature iron filings, the activated carbon 25 is used to adsorb organic gas and part of peculiar smell, the output end movement of the telescopic air cylinder 44 drives the clamping pipe 45 to move, and the metal blank is pushed to the middle of the base plate 28, the output end rotation of the motor 5 drives the first lead screw 46 and the second lead screw 47 to rotate, the first lead screw 46 and the second lead screw 47 are opposite in thread, the first clamping plate 50 and the second clamping plate 51 move towards each other, and the metal blank is pushed to the center position of the base plate 28, then the telescopic air cylinder 44 is reset, then the hydraulic cylinder 16 is started, the output end movement of the hydraulic cylinder 16 drives the hydraulic hammer body 15 to move downwards, and the metal blank is forged, after the hydraulic hammer body 15 contacts the metal blank, it continues to move downwards, the trigger assembly 26 enters the groove 30, and the base plate 28 contacts the first limiting plate 31 until the first spring 33 is compressed, the first piston 34 pressurizes the hydraulic oil in the cavity 35 into the pushing cavity 43 through the second connecting pipe 41, at this time, the second piston 40 moves upwards to drive the connecting rod 52 to move upwards, the connecting rod 52 moves upwards to drive the push plate 37 to move upwards, the push plate 37 moves upwards to drive the baffle plate 36 to move upwards until the second piston 40 contacts the second limiting plate 39, at this time, the second spring 38 is compressed, the baffle plate 36 is used to block around the metal blank, prevent the metal blank from being hit to generate sparks, metal slag, burn the skin or ignite the combustible, after the forging assembly 9 completes the forging, the output end of the hydraulic cylinder 16 is reset, then the second spring 38 pushes the push plate 37 to reset, the first spring 33 pushes the pressing plate 32 to reset, and the base plate 28 rises above the groove 30, the above is the working process of the whole invention, and the above steps can be repeated next time.

[0043] The above description of disclosed embodiments enables one of ordinary skill in the art to make or use the invention. Various modifications to these embodiments will be apparent to those of ordinary skill in the art, and the generic principles defined herein can be applied to other embodiments without departing from the spirit or scope of the invention. Therefore, the invention is not to be limited to the embodiments shown herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A forging machine with a safeguarding mechanism, comprising a machine body (1) and a positioning assembly (4) arranged on the machine body (1), the machine body (1) comprising a device cavity (6) and a machine lower cavity (8), characterized in that: The air curtain protection mechanism (2) is arranged on the machine tool body (1), and the telescopic shield mechanism (3) is arranged on the machine tool body (1); the air curtain protection mechanism (2) comprises a forging and pressing assembly (9), a high-speed thin gas flow layer assembly (10) and a metal collecting assembly (11), the forging and pressing assembly (9) is arranged on the air curtain protection mechanism (2), the high-speed thin gas flow layer assembly (10) is arranged on the air curtain protection mechanism (2), and the metal collecting assembly (11) is arranged on the air curtain protection mechanism (2); the high-speed thin gas flow layer assembly (10) comprises a square frame (17), the square frame (17) is installed at the lower end of the equipment cavity (6), four long strip air outlet seams (18) are formed in the lower end of the square frame (17), one end of a metal connecting pipe (20) is connected through the outer side wall of the square frame (17), the other end of the metal connecting pipe (20) is connected through one end of a connecting hose (21), the other end of the connecting hose (21) is installed at the output end of a high-pressure air blower (19), and the air suction end of the high-pressure air blower (19) is connected through the lower end of the outer side wall of the machine tool lower cavity (8); the telescopic shield mechanism (3) comprises a trigger assembly (26) and a telescopic local protection assembly (27); the machine tool body (1) comprises a machine tool lower cavity (8), the machine tool lower cavity (8) is provided with a machine tool frame (7), and the inner top end of the machine tool frame (7) is provided with an equipment cavity (6); the forging and pressing assembly (9) comprises a bearing base (12), the bearing base (12) is arranged in the machine tool lower cavity (8), a hydraulic cylinder (16) is installed in the equipment cavity (6), the output end of the hydraulic cylinder (16) is connected with a hydraulic hammer body (15), a square frame type air inlet groove (13) is formed in the top end of the machine tool lower cavity (8), and the square frame type air inlet groove (13) and the machine tool lower cavity (8) are fixedly connected through a connecting rib (14); the trigger assembly (26) comprises a groove (30), the groove (30) is arranged at the inner top end of the bearing base (12), one end of a first spring (33) is fixedly connected to the inner bottom end of the groove (30), the other end of the first spring (33) is fixedly connected with a pressing plate (32), the pressing plate (32) is fixedly sleeved with a first connecting pipe (29), a cavity (35) is fixedly connected to the lower end of the groove (30), a first limiting plate (31) is fixedly connected to the inner side wall of the groove (30), the first limiting plate (31) is arranged above the pressing plate (32), the top end of the first connecting pipe (29) is fixedly connected with a base disc (28), the bottom end of the first connecting pipe (29) is fixedly connected with a first piston (34), the first piston (34) is slidably arranged in the cavity (35), and the first connecting pipe (29) is slidably sleeved on the first limiting plate (31).The telescopic local protection assembly (27) comprises a storage cavity (42), which is arranged at the inner top end of the load-bearing base (12), the lower end of the storage cavity (42) is connected with a push cavity (43) in a penetrating mode, one end of the outer side wall of the cavity (35) is connected with one end of a second connecting pipe (41) in a penetrating mode, the other end of the second connecting pipe (41) is connected with the lower end of the push cavity (43) in a penetrating mode, a second piston (40) is arranged in the push cavity (43) in a sliding mode, the upper end of the second piston (40) is fixedly connected with a connecting rod (52), the upper end of the connecting rod (52) is fixedly connected with a push plate (37), the inner side wall of the push cavity (43) is fixedly connected with a second limiting plate (39) in an upper mode, the connecting rod (52) is arranged in the second limiting plate (39) in a sliding mode, the push plate (37) is arranged in the storage cavity (42), the top end of the push plate (37) is fixedly connected with a baffle (36), one end of the push plate (37) is fixedly connected with one end of a second spring (38), the other end of the second spring (38) is fixedly connected to the inner top end of the storage cavity (42).

2. A forging machine as claimed in claim 1, wherein: The metal collecting assembly (11) comprises a water pool (22), the inner bottom end of the machine tool lower cavity (8) is provided with the water pool (22), the inner bottom wall of the water pool (22) is provided with a magnet (23), the inner side wall of the machine tool lower cavity (8) is fixedly connected with a metal mesh cage (24), and the metal mesh cage (24) is provided with activated carbon (25) inside.

3. A forging machine as claimed in claim 2, wherein: The second connecting pipe (41) and the cavity (35) are provided with hydraulic oil, and the hydraulic oil is arranged below the cavity (35).

4. A forging machine as claimed in claim 3, wherein: The positioning assembly (4) comprises a telescopic air cylinder (44), the telescopic air cylinder (44) is arranged in the machine tool frame (7), the output end of the telescopic air cylinder (44) is fixedly connected with a clamping pipe (45), one end of the clamping pipe (45) is fixedly connected with a motor (5), the output end of the motor (5) is fixedly connected with a first lead screw (46), one end of the first lead screw (46) is fixedly connected with one end of a second lead screw (47), the other end of the second lead screw (47) is rotatably connected with one end of the clamping pipe (45), a first sleeve pipe (48) is sleeved on the first lead screw (46), the first lead screw (46) and the first sleeve pipe (48) are screw-connected, a second sleeve pipe (49) is sleeved on the second lead screw (47), the second lead screw (47) and the second sleeve pipe (49) are screw-connected, the first sleeve pipe (48) and the second sleeve pipe (49) are the same in structure, one side of the first sleeve pipe (48) is fixedly connected with a first clamping plate (50), one side of the second sleeve pipe (49) is fixedly connected with a second clamping plate (51), and the threads of the first lead screw (46) and the second lead screw (47) are opposite.

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