Numerical control planing table horizontal milling and boring machine

Abstract

The utility model discloses a numerical control planing platform horizontal type milling and boring machine which comprises a supporting base, a saddle is arranged at the top of the supporting base, fixing grooves are formed in the two sides of the top of the supporting base, first racks are fixedly connected to the portions, located in the fixing grooves, of the supporting base, and limiting devices are installed on the front portions and the rear portions of the two sides of the bottom of the saddle. And the limiting devices and the fixing grooves are correspondingly arranged, first hydraulic cylinders are installed in the limiting devices at equal intervals, the output ends of the first hydraulic cylinders are fixedly connected with second racks, and the second racks are connected with the first racks in a matched mode. The utility model relates to the technical field of horizontal milling and boring machines, and solves the problems that in the prior art, after a workpiece is moved to a designated position by a front lathe bed, the workpiece is fixed by abutting against a sliding rail, so that the workpiece is poor in stability when being stressed during machining, the workpiece is easy to loosen or shift, the machining precision of the workpiece is influenced, and the sliding rail is abraded to a certain extent.

Description

Technical Field

[0001] The utility model relates to the technical field of horizontal milling and boring machines, in particular to a horizontal milling and boring machine with a numerically controlled planing table. Background Art

[0002] As an important processing equipment, CNC planer horizontal milling and boring machine is widely used in cutting and processing of various parts such as plates, discs, shells, molds, etc. The CNC system is used to control the movement of various components such as the workbench, tool magazine, spindle, etc., and the precise processing of the processing object is achieved through mathematical models. During the processing, the CNC system will automatically calculate and control the motion parameters of each part, so as to achieve high-precision, high-efficiency and easy-to-operate processing. The horizontal milling and boring machine is generally divided into a front bed for fixing the workpiece and a rear bed for installing the processing tool. In the prior art, after the front bed moves the workpiece to the specified position, it is fixed by tightening the slide rail, resulting in poor stability of the workpiece when it is subjected to force during processing, and it is easy to loosen or shift, affecting the processing accuracy of the workpiece, and causing certain wear on the slide rail. Summary of the invention

[0003] In view of the deficiencies in the prior art, the utility model provides a CNC planer horizontal milling and boring machine, which solves the problem in the prior art that after the front bed moves the workpiece to a specified position, it is fixed by tightening the slide rail, resulting in poor stability of the workpiece when subjected to force during processing, and is prone to loosening or shifting, affecting the processing accuracy of the workpiece and causing certain wear to the slide rail.

[0004] To achieve the above-mentioned purpose, the utility model is implemented through the following technical solutions: a CNC planer horizontal milling and boring machine, including a support base, a saddle is arranged on the top of the support base, fixed grooves are opened on both sides of the top of the support base, and the support base is fixedly connected with a first rack inside the fixed groove, and limiting devices are installed on both sides of the bottom of the saddle in front and behind, and the limiting devices are arranged corresponding to the fixed grooves. A first hydraulic cylinder is equidistantly installed inside the limiting device, and the output end of the first hydraulic cylinder is fixedly connected with a second rack, and the second rack is matched with the first rack. A moving seat is arranged on the top of the saddle, and a rotary worktable is arranged on the top of the moving seat, a rear bed is arranged on one side of the support base, a spindle box is installed inside the rear bed, and a spindle is arranged inside the spindle box, a hydraulic station is arranged on one side of the rear bed, the first hydraulic cylinder is connected to the hydraulic station, and a controller is arranged on the other side of the rear bed, and the hydraulic station is electrically connected to the controller.

[0005] Preferably, a first laser ranging sensor is installed on the side of the top of the support base away from the rear bed, and the first laser ranging sensor is arranged corresponding to the saddle. A second laser ranging sensor is installed on one side of the top of the saddle, and the second laser ranging sensor is arranged corresponding to the moving seat. A third laser ranging sensor is installed on the top of the rear bed, and the third laser ranging sensor is arranged corresponding to the main shaft. The first laser ranging sensor, the second laser ranging sensor and the third laser ranging sensor are all electrically connected to the controller.

[0006] Preferably, the support base and the saddle are both rotatably connected inside with a first ball screw, and a first servo motor is installed on one side of the support base and the saddle, the output end of the first servo motor is transmission connected to the first ball screw, the first ball screw located inside the support base is threadedly connected to the saddle, and the first ball screw located inside the saddle is threadedly connected to the movable seat, and slide rails are equidistantly fixedly connected to both sides of the top of the support base and the saddle, the slide rails located on the top of the support base are cooperatively connected to the saddle, and the slide rails located on the top of the saddle are cooperatively connected to the movable seat.

[0007] Preferably, the rear bed is internally rotatably connected with a second ball screw, the second ball screw is threadedly connected to the spindle box, a second servo motor is installed on the top of the rear bed, the output end of the second servo motor is transmission connected to the second ball screw, a second hydraulic cylinder is installed on the top of the rear bed on the other side of the second servo motor, the second hydraulic cylinder is communicated with the hydraulic station, the output end of the second hydraulic cylinder is fixedly connected to the spindle box, the rear bed is fixedly connected with vertical rails on both sides of the spindle, and the spindle box is cooperatively connected to the vertical rails.

[0008] Preferably, the output ends of the first servo motor and the second servo motor are both provided with planetary gear reducers, and the planetary gear reducers are respectively transmission-connected to the first ball screw and the second ball screw, and both ends of the first ball screw and the second ball screw are provided with bearing seats.

[0009] The utility model provides a CNC planer horizontal milling and boring machine. It has the following beneficial effects: the CNC planer horizontal milling and boring machine, through the cooperation among the support base, the saddle, the fixing groove, the first rack, the limiting device, the first hydraulic cylinder, the second rack, the hydraulic station and the controller, and by setting an independent limiting device between the support base and the saddle, after the workpiece is moved to the specified position, the CNC system will automatically trigger the telescopic rod of the first hydraulic cylinder to extend, so that the second rack moves downward and is pressed against the first rack, and the teeth of the second rack and the first rack are engaged with each other to limit the position, without pressing the slide rail tightly, reducing the wear on the slide rail, helping to extend the service life of the slide rail, and making the saddle more stably fixed, thereby ensuring the stability of the workpiece under force, which helps to improve the processing accuracy of the CNC milling and boring machine and the qualified rate of the workpiece.

[0010] Through the coordination among the supporting base, saddle, moving seat, rear bed, spindle, first laser ranging sensor, second laser ranging sensor and third laser ranging sensor, the moving distances of the saddle, moving seat and spindle are measured respectively by each laser ranging sensor, and the measuring signals are transmitted to the control system of the horizontal boring and milling machine in real time, so that the control system can precisely control each driving electrical component, so that the workpiece and the machining tool can be precisely controlled to move. Compared with the traditional positioning method, it can reduce the influence of mechanical vibration on the measurement data, thereby improving the accuracy and stability of the machine tool during the machining process. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] Figure 1 This is a schematic diagram of the appearance of the utility model;

[0012] Figure 2 for Figure 1 Schematic diagram of the appearance of the middle support base, the slide rail and the first laser ranging sensor;

[0013] Figure 3 for Figure 1 Schematic diagram of the appearance of the middle saddle, moving seat and rotary table;

[0014] Figure 4 for Figure 3 Schematic diagram of the appearance of the middle limit device;

[0015] Figure 5 for Figure 2 A partial enlarged view of area A.

[0016] In the figure: 1. support base, 2. saddle, 3. fixed groove, 4. first rack, 5. limit device, 6. first hydraulic cylinder, 7. second rack, 8. movable seat, 9. rotary table, 10. rear bed, 11. spindle box, 12. spindle, 13. hydraulic station, 14. controller, 15. first laser ranging sensor, 16. second laser ranging sensor, 17. third laser ranging sensor, 18. first ball screw, 19. first servo motor, 20. slide rail, 21. second ball screw, 22. second servo motor, 23. second hydraulic cylinder, 24. vertical rail, 25. planetary gear reducer, 26. bearing seat. DETAILED DESCRIPTION

[0017] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments in the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0018] In the prior art, after the front bed moves the workpiece to a specified position, it is fixed by tightening the slide rail, which results in poor stability of the workpiece when subjected to force during processing, and is prone to loosening or shifting, affecting the processing accuracy of the workpiece and causing certain wear to the slide rail.

[0019] In view of this, the utility model provides a CNC planer horizontal milling and boring machine, which cooperates with a supporting base, a saddle, a fixing groove, a first rack, a limiting device, a first hydraulic cylinder, a second rack, a hydraulic station and a controller, and an independent limiting device is arranged between the supporting base and the saddle. After the workpiece is moved to a specified position, the CNC system will automatically trigger the telescopic rod of the first hydraulic cylinder to extend, so that the second rack moves downward and is tightly pressed against the first rack. The teeth of the second rack and the first rack are engaged and limited with each other, so that the saddle is more stably fixed, thereby ensuring the stability of the workpiece when subjected to force, improving the machining accuracy of the CNC milling and boring machine, and there is no need to tighten the slide rail, thereby reducing the wear on the slide rail and extending the service life of the slide rail.

[0020] Through the personnel in this field, all the electrical components in this case are connected to their corresponding power supplies through wires, and appropriate controllers and encoders should be selected according to actual conditions to meet the control requirements. The specific connection and control sequence should refer to the following working principle, and the electrical connection between the electrical components is completed in the order of working in sequence. The detailed connection means are well-known technologies in this field. The following mainly introduces the working principles and processes, and no longer explains the electrical control.

[0021] Depend on Figure 1-5It can be seen that a CNC planer horizontal milling and boring machine includes a supporting base 1, a saddle 2 is arranged on the top of the supporting base 1, and fixing grooves 3 are opened on both sides of the top of the supporting base 1. The supporting base 1 is located inside the fixing groove 3 and is fixedly connected with a first rack 4. Limiting devices 5 are installed on both sides of the bottom of the saddle 2, and the limiting devices 5 are arranged corresponding to the fixing groove 3. First hydraulic cylinders 6 are equidistantly installed inside the limiting devices 5, and the output ends of the first hydraulic cylinders 6 are fixedly connected with second racks 7, and the second racks 7 are matched with the first rack 4. A moving seat 8 is arranged on the top of the saddle 2, and a rotary table 9 is arranged on the top of the moving seat 8. The rotary table 9 is used to clamp the workpiece and realize rotation and indexing positioning. It adopts hydraulic drive and can drive the workpiece to rotate at a specified angle, thereby realizing all-round operation of the workpiece, making the processing process more flexible, and then the processing In order to meet the processing requirements of the workpiece at different positions and angles, a rear bed 10 is arranged on one side of the support base 1, a spindle box 11 is installed inside the rear bed 10, a spindle 12 is arranged inside the spindle box 11, a hydraulic station 13 is arranged on one side of the rear bed 10, the hydraulic station 13 is used to transmit hydraulic power to the hydraulic components of the horizontal milling and boring machine, ensuring that the hydraulic components of the horizontal milling and boring machine can be accurately operated according to the preset degree, the first hydraulic cylinder 6 is connected to the hydraulic station 13, and a controller 14 is arranged on the other side of the rear bed 10, the controller 14 is used to accurately operate the electrical components and hydraulic components of the horizontal milling and boring machine according to the preset degree, and has a CNC programming function, so that the operator can set a series of complex processing processes through programming, so that the horizontal CNC milling and boring machine can automatically complete the processing of the workpiece, and the hydraulic station 13 is electrically connected to the controller 14;

[0022] In the specific implementation process, it is worth pointing out that the rear bed of the CNC milling and boring machine is formed by the cooperation between the supporting base 1, the saddle 2, the moving seat 8 and the rotary table 9, which is used to fix the workpiece to be processed, and the driving components of the rear bed are controlled by the CNC system, so that the workpiece can be moved horizontally and vertically. The rotary table 9 is used to clamp the workpiece and realize rotation and indexing positioning. It adopts hydraulic drive and can drive the workpiece to rotate at a specified angle, thereby realizing all-round operation of the workpiece, making the processing process more flexible, and then the workpiece can be processed at different positions and different The same angle processing needs, through the cooperation between the rear bed 10, the spindle box 11 and the spindle 12, the spindle 12 can replace the processing tool according to the use needs, and the oil film clearance is realized by the constant pressure static pressure bearing, which greatly avoids the resonance tremor and the phenomenon of the processing tool extending forward and lowering. The rear bed 10 is equipped with a driving component and a positioning component for controlling the lifting of the spindle box 11, and the spindle box 11 is equipped with a driving component of the spindle 12, so that the processing tool can be moved vertically, and the processing tool can be extended and driven, so as to realize the processing of the workpiece. The hydraulic station 13 is used to transmit hydraulic power to each hydraulic group of the horizontal milling and boring machine. The controller 14 is used to accurately operate the electrical components and hydraulic components of the horizontal milling and boring machine according to the preset degree, and has a numerical control programming function, so that the operator can set a series of complex processing processes through programming, so that the horizontal numerical control milling and boring machine can automatically complete the processing of the workpiece. Through the cooperation between the support base 1, the saddle 2, the fixing groove 3, the first rack 4, the limit device 5, the first hydraulic cylinder 6, the second rack 7, the hydraulic station 13 and the controller 14, by setting a unique hydraulic cylinder between the support base 1 and the saddle 2 The saddle 2 is fixed more stably through the teeth of the second rack 7 and the first rack 4, thereby ensuring the stability of the workpiece under stress, improving the processing accuracy of the CNC milling and boring machine, and eliminating the need to tighten the slide rail, thereby reducing the wear on the slide rail and extending the service life of the slide rail. The specific models of the first hydraulic cylinder 6, the hydraulic station 13 and the controller 14 are not limited, and can meet the use requirements.

[0023] Further, a first laser ranging sensor 15 is installed on the top of the support base 1 on a side away from the rear bed 10, and the first laser ranging sensor 15 is arranged corresponding to the saddle 2. A second laser ranging sensor 16 is installed on one side of the top of the saddle 2, and the second laser ranging sensor 16 is arranged corresponding to the moving seat 8. A third laser ranging sensor 17 is installed on the top of the rear bed 10, and the third laser ranging sensor 17 is arranged corresponding to the spindle 12. The first laser ranging sensor 15, the second laser ranging sensor 16 and the third laser ranging sensor 17 are all electrically connected to the controller 14;

[0024] In the specific implementation process, it is worth pointing out that, through the cooperation between the support base 1, the saddle 2, the moving seat 8, the rear bed 10, the spindle 12, the first laser ranging sensor 15, the second laser ranging sensor 16 and the third laser ranging sensor 17, the moving distances of the saddle 2, the moving seat 8 and the spindle 12 are measured respectively by each laser ranging sensor, and the measurement signal is transmitted to the control system of the horizontal milling and boring machine in real time, so that the control system can accurately control each driving electrical component, so that the processing workpiece and the processing tool can be accurately controlled to move. Compared with the traditional measurement method (such as displacement sensor), it can reduce the influence of mechanical vibration on the measurement data, thereby improving the accuracy and stability of the machine tool during the processing process. The specific models of the first laser ranging sensor 15, the second laser ranging sensor 16 and the third laser ranging sensor 17 are not limited, and they can meet the use requirements;

[0025] Furthermore, the inside of the support base 1 and the saddle 2 are both rotatably connected with a first ball screw 18, one side of the support base 1 and the saddle 2 are both installed with a first servo motor 19, the output end of the first servo motor 19 is transmission-connected with the first ball screw 18, the first ball screw 18 located inside the support base 1 is threadedly connected to the saddle 2, the first ball screw 18 located inside the saddle 2 is threadedly connected to the moving seat 8, and both sides of the top of the support base 1 and the saddle 2 are equidistantly fixedly connected with slide rails 20, the slide rail 20 located on the top of the support base 1 is cooperatively connected to the saddle 2, and the slide rail 20 located on the top of the saddle 2 is cooperatively connected to the moving seat 8;

[0026] In the specific implementation process, it is worth pointing out that, through the cooperation among the support base 1, the saddle 2, the first ball screw 18, the first servo motor 19 and the slide rail 20, by controlling the first servo motor 19 located on the support base 1, the first ball screw 18 is driven to rotate, so that the saddle 2 is stably moved horizontally along the axial direction of the first ball screw 18 in the support base 1, and then the saddle 2 can drive the rotary table 9 and the workpiece to be processed to the desired position stably, so as to control the processing tool to accurately process the workpiece, through the cooperation among the saddle 2, the moving seat 8, the first ball screw 18, the first servo motor 19 and the slide rail 20, by controlling the first servo motor 19 located on the saddle 2, the first ball screw 1 is driven 8 is rotated, so that the moving seat 8 can stably move horizontally along the axial direction of the first ball screw 18 in the saddle 2, so that the rotary table 9 can drive the workpiece to move stably to the desired position, so as to control the processing tool to accurately process the workpiece. Through the cooperation between the supporting base 1, the saddle 2, the moving seat 8, the first ball screw 18, the first servo motor 19 and the slide rail 20, the control system of the CNC milling and boring machine automatically controls the first servo motor 19, so that the workpiece can be stably moved horizontally in the horizontal and longitudinal directions, so that the workpiece can be accurately moved to the desired position, so that the processing tool can accurately perform processing operations, wherein the specific model of the first servo motor 19 is not limited, and it can meet the use requirements;

[0027] Further, the rear bed 10 is internally rotatably connected with a second ball screw 21, the second ball screw 21 is threadedly connected to the spindle box 11, a second servo motor 22 is installed on the top of the rear bed 10, the output end of the second servo motor 22 is transmission-connected to the second ball screw 21, a second hydraulic cylinder 23 is installed on the top of the rear bed 10 on the other side of the second servo motor 22, the second hydraulic cylinder 23 is communicated with the hydraulic station 13, the output end of the second hydraulic cylinder 23 is fixedly connected to the spindle box 11, the rear bed 10 is fixedly connected with vertical rails 24 on both sides of the spindle 12, and the spindle box 11 is cooperatively connected with the vertical rails 24;

[0028] In the specific implementation process, it is worth pointing out that the position limitation of the spindle box 11 is achieved through the cooperation between the rear bed 10, the spindle box 11 and the vertical rail 24, and the stability of the spindle box 11 during lifting and moving is improved. Through the cooperation between the rear bed 10, the spindle box 11, the controller 14, the hydraulic station 13, the second ball screw 21, the second servo motor 22, the second hydraulic cylinder 23 and the vertical rail 24, the second servo motor 22 and the second hydraulic cylinder 23 are controlled to drive the second ball screw 21 to rotate and the telescopic rod of the second hydraulic cylinder 23 to extend and retract, so that the spindle 12 of the spindle box 11 can drive the machining tool to move stably to the required height for precise machining operations. At the same time, the second hydraulic cylinder 23 can balance the force on the spindle box 11 and support and fix it, effectively avoiding vibration or deviation caused by uneven force, ensuring the accuracy of mechanical processing, and extending the service life of the spindle box 11 and its related components. The specific models of the second servo motor 22 and the second hydraulic cylinder 23 are not limited, and it is sufficient to meet the use requirements.

[0029] Furthermore, the output ends of the first servo motor 19 and the second servo motor 22 are both provided with a planetary gear reducer 25, and the planetary gear reducer 25 is respectively connected to the first ball screw 18 and the second ball screw 21 in transmission, and both ends of the first ball screw 18 and the second ball screw 21 are provided with a bearing seat 26;

[0030] In the specific implementation process, it is worth pointing out that the bearing seat 26 is used to support and fix the first ball screw 18 and the second ball screw 21 to ensure the accuracy of the position and direction of each ball screw, so that the ball screw can rotate smoothly and ensure the driving stability of the ball screw. The planetary gear reducer 25 is used to change the output speed of the assembled servo motor to meet the needs of the working mechanism, so that each servo motor can achieve deceleration, acceleration or variable speed output.

[0031] It should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions. The sentence "includes an element defined by ... does not exclude the existence of other identical elements in the process, method, article or device including the element".

[0032] In the present utility model, unless otherwise clearly stipulated and limited, the terms such as "installation", "setting", "connection", "fixation" and "screw-on" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integrated connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. Unless otherwise clearly defined, ordinary technicians in this field can understand the specific meanings of the above terms in the utility model according to the specific circumstances.

[0033] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A CNC planer horizontal milling and boring machine, comprising a support base (1), characterized in that: A saddle (2) is arranged on the top of the support base (1), and fixing grooves (3) are provided on both sides of the top of the support base (1). The support base (1) is fixedly connected with a first rack (4) inside the fixing groove (3). Limiting devices (5) are installed on both sides of the bottom of the saddle (2) at the front and rear, and the limiting devices (5) are arranged corresponding to the fixing grooves (3). First hydraulic cylinders (6) are equidistantly installed inside the limiting devices (5), and the output ends of the first hydraulic cylinders (6) are fixedly connected with second racks (7), and the second racks (7) are cooperatively connected with the first racks (4). A movable seat (8) is arranged on the top of the saddle (2), a rotary table (9) is arranged on the top of the movable seat (8), a rear bed (10) is arranged on one side of the support base (1), a spindle box (11) is installed inside the rear bed (10), a spindle (12) is arranged inside the spindle box (11), a hydraulic station (13) is arranged on one side of the rear bed (10), the first hydraulic cylinder (6) is connected to the hydraulic station (13), a controller (14) is arranged on the other side of the rear bed (10), and the hydraulic station (13) is electrically connected to the controller (14).

2. The CNC planer horizontal milling and boring machine according to claim 1, characterized in that: A first laser distance measuring sensor (15) is installed on a side of the top of the support base (1) away from the rear bed (10), the first laser distance measuring sensor (15) being arranged corresponding to the saddle (2), a second laser distance measuring sensor (16) is installed on one side of the top of the saddle (2), the second laser distance measuring sensor (16) being arranged corresponding to the movable seat (8), a third laser distance measuring sensor (17) is installed on the top of the rear bed (10), the third laser distance measuring sensor (17) being arranged corresponding to the spindle (12), and the first laser distance measuring sensor (15), the second laser distance measuring sensor (16) and the third laser distance measuring sensor (17) are all electrically connected to a controller (14).

3. The CNC planer horizontal milling and boring machine according to claim 1, characterized in that: The support base (1) and the saddle (2) are both rotatably connected with a first ball screw (18), and one side of the support base (1) and the saddle (2) is equipped with a first servo motor (19), the output end of the first servo motor (19) is transmission-connected with the first ball screw (18), the first ball screw (18) located inside the support base (1) is threadedly connected to the saddle (2), and the first ball screw (18) located inside the saddle (2) is threadedly connected to the movable seat (8), and both sides of the top of the support base (1) and the saddle (2) are equidistantly fixedly connected with slide rails (20), the slide rail (20) located at the top of the support base (1) is cooperatively connected to the saddle (2), and the slide rail (20) located at the top of the saddle (2) is cooperatively connected to the movable seat (8).

4. The CNC planer horizontal milling and boring machine according to claim 3, characterized in that: The rear bed (10) is internally rotatably connected with a second ball screw (21), the second ball screw (21) is threadedly connected to the spindle box (11), a second servo motor (22) is installed on the top of the rear bed (10), the output end of the second servo motor (22) is transmission-connected to the second ball screw (21), a second hydraulic cylinder (23) is installed on the top of the rear bed (10) on the other side of the second servo motor (22), the second hydraulic cylinder (23) is communicated with the hydraulic station (13), the output end of the second hydraulic cylinder (23) is fixedly connected to the spindle box (11), the rear bed (10) is fixedly connected with vertical rails (24) on both sides of the spindle (12), and the spindle box (11) is cooperatively connected to the vertical rails (24).

5. The CNC planer horizontal milling and boring machine according to claim 4, characterized in that: The output ends of the first servo motor (19) and the second servo motor (22) are both provided with planetary gear reducers (25), the planetary gear reducers (25) are respectively connected to the first ball screw (18) and the second ball screw (21) in a transmission manner, and the first ball screw (18) and the second ball screw (21) are both provided with bearing seats (26) at both ends.

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