Ultrasonic machining center for ultrasonic microforged low-roughness surface

Abstract

This invention discloses an ultrasonic machining center for ultrasonic micro-forging of low-roughness surfaces, belonging to the technical field of ultrasonic machining centers. It includes a machining bed with an operating table mounted on it. A machine head is mounted on one side of the machining bed, and a tool magazine is mounted on one side of the machine head. A mounting plate is installed inside the machine head, and an ultrasonic transducer is mounted at the bottom of the mounting plate. An amplitude transformer is mounted at the bottom of the ultrasonic transducer, and a connector is mounted at the bottom of the amplitude transformer. Through a combination structure of ball joints, multiple sets of limiting cylinders, limiting rods, and buffer springs, the micro-forging head can automatically maintain a vertical reference posture when unloaded, ensuring initial machining alignment accuracy and avoiding machining defects caused by misalignment. With the help of the ball joint hinge and the limiting telescopic buffer structure, the micro-forging head can automatically adjust its tilt to adapt to workpiece inclined surfaces, irregular curved surfaces, and uneven surfaces, achieving conformal machining and solving the pain points of traditional rigid micro-forging heads being unable to adapt to irregular workpieces and experiencing uneven local force.

Description

Technical Field

[0001] This invention belongs to the technical field of ultrasonic machining centers, specifically, it relates to an ultrasonic machining center for ultrasonic micro-forging of low-roughness surfaces. Background Technology

[0002] Ultrasonic micro-forging technology is an emerging surface finishing method. It involves applying high-frequency ultrasonic vibrations to a cutting tool or micro-forging head to forge the material surface at high frequency and small amplitudes, thereby reducing surface roughness, eliminating residual tensile stress, and improving surface microstructure. This technology is widely used in fields with high surface quality requirements, such as precision molds, aerospace parts, and medical devices.

[0003] Currently, some machining centers integrating ultrasonic vibration systems have appeared on the market. These typically consist of a machining bed, operating table, machine head, tool magazine, and ultrasonic generator. The ultrasonic vibration is transmitted to the micro-forging head via a converter and amplitude transformer to achieve micro-forging treatment of the workpiece surface. However, in practical applications, existing equipment still has the following technical shortcomings:

[0004] The impact of high-frequency vibration on machine tool accuracy and lifespan: During ultrasonic micro-forging, the high-frequency mechanical vibration generated by the micro-forging head is transmitted in reverse to structural components such as the machine head, guide rails, and machine bed. Existing machining centers lack effective vibration damping and isolation designs, which can easily lead to spindle bearing wear, decreased guide rail accuracy, and even affect the dynamic stability of the entire machine, reducing machining quality and equipment lifespan with long-term use.

[0005] Difficulty adapting to irregular or inclined surfaces: Traditional micro forging heads and mounting rods are mostly rigidly connected. When the surface of the material being processed has a slight inclination, curvature, or local unevenness, the micro forging head cannot automatically adjust its posture, resulting in uneven distribution of contact pressure, with some areas being over-forged and others under-forged, ultimately affecting the uniformity of the low-roughness surface.

[0006] Uneven workpiece clamping pressure and easy deformation: Existing machining centers mostly use mechanical clamping plates or cylinders to clamp the workpiece at one or two points from top to bottom. For thin-walled parts, irregularly shaped parts or soft materials, single-point pressure can easily cause local deformation or warping of the workpiece; at the same time, it is difficult to keep the pressure of each clamping point consistent, resulting in micro-displacement of the workpiece during the machining process, which affects the accuracy of micro-forging. To address the aforementioned issues, this application proposes an ultrasonic machining center for ultrasonic micro-forging of low-roughness surfaces. Summary of the Invention

[0007] To address the problems in related technologies, this invention proposes an ultrasonic machining center for ultrasonic micro-forging of low-roughness surfaces, thereby overcoming the aforementioned technical problems existing in the prior art.

[0008] To achieve the above objectives, the present invention adopts the following technical solution: An ultrasonic machining center for ultrasonic micro-forging of low-roughness surfaces includes a machining bed, an operating table mounted on the machining bed, a machine head mounted on one side of the machining bed, a tool magazine mounted on one side of the machine head, a mounting plate mounted inside the machine head, an ultrasonic transducer mounted at the bottom of the mounting plate, an amplitude transformer mounted at the bottom of the ultrasonic transducer, a connector mounted at the bottom of the amplitude transformer, a mounting base mounted at the bottom of the connector, and an ultrasonic generator mounted on one side of the machine head. The shock absorption mechanism includes a shock absorption box, which is fixedly installed inside the machine head. A force-bearing column is slidably connected to the bottom of the shock absorption box, and the force-bearing column is fixedly connected to the mounting plate. An isobaric micro-forging mechanism includes a micro-forging head, a mounting rod fixedly mounted on the bottom of a mounting base, a ball joint rotatably mounted on the bottom end of the mounting rod, and the ball joint being fixedly connected to the micro-forging head. The multi-point isobaric fixing mechanism includes two L-shaped support seats, which are fixedly installed on the top of the operating table. A pressure injection box is installed on the top of the L-shaped support seats, and multiple pressure heads are installed on the bottom of the pressure injection box.

[0009] Preferably, the shock absorption mechanism further includes a piston plate, which is slidably mounted on the inner wall of the shock absorption box, and the force-bearing column is fixedly connected to the piston plate, with the piston plate and the inner wall of the shock absorption box in close contact with each other.

[0010] Preferably, an adjusting plate is slidably connected to the inner wall of the shock absorber box, the adjusting plate is in close contact with the inner wall of the shock absorber box, and a pad rod is fixedly installed on the top of the adjusting plate, the pad rod being slidably connected to the top of the shock absorber box.

[0011] Preferably, the isobaric micro-forging mechanism further includes six limiting cylinders, each with a limiting rod slidably connected to its bottom. A positioning plate is fixedly installed on the mounting rod, and the limiting cylinders and limiting rods are rotatably connected to the positioning plate and the micro-forging head, respectively.

[0012] Preferably, a piston block is slidably connected to the inner wall of the limiting cylinder, the piston block is fixedly connected to the limiting rod, and a buffer spring is fixedly installed on the top of the piston block, with the top end of the buffer spring fixedly connected to the top inner wall of the limiting cylinder.

[0013] Preferably, a mounting bracket is fixedly installed on the mounting rod, the mounting bracket has a slot, and a tool changing arm is provided at the bottom of the tool magazine, with the slot engaging with the tool changing arm.

[0014] Preferably, the multi-point isobaric fixing mechanism includes multiple injection cylinders, which are respectively fixedly installed at the bottom of the injection box, and the top of the injection cylinders are connected to the injection box. A pressure rod is slidably connected to the bottom of the injection cylinder, and the top pressure head is fixedly connected to the corresponding pressure rod.

[0015] Preferably, a plug is slidably connected to the inner wall of the injection cylinder, the plug is in contact with the inner wall of the injection cylinder, and the plug is fixedly connected to the pressure rod. A return spring is fixedly installed at the bottom of the plug, and the bottom end of the return spring is fixedly connected to the bottom inner wall of the injection cylinder.

[0016] Preferably, a conversion box is installed on one side of the operating table, and two conduits are installed on the top of the conversion box, with one end of the conduits communicating with the corresponding injection box.

[0017] Preferably, the top of the operating table is provided with multiple convex grooves, and a limit block is slidably connected in the convex grooves. The bottom of the L-shaped support base is provided with multiple bolts, and the bolts are threadedly connected to the limit block.

[0018] In summary, the technical effects and advantages of this invention are as follows: The airtight piston-pneumatic shock absorption structure utilizes the high-pressure air resistance created by the compression of air inside the shock absorber box to effectively absorb the vibration force transmitted in the reverse direction of the high-frequency ultrasonic vibration of the micro-forging head. This significantly attenuates the vibration transmitted to the machine head and machining bed, preventing resonance deformation of the machine bed and ensuring the stability of equipment operation and machining accuracy. An adjustable pneumatic structure with screws, pads, and adjusting plates allows for adjustment of the internal air pressure intensity of the shock absorber box as needed, adapting to micro-forging operations with different ultrasonic frequencies and workpiece materials. The shock absorption intensity is adjustable and controllable, meeting the needs of various processing conditions. The force-bearing column is rigidly connected to the mounting plate, and the piston plate is sealed to the inner wall of the shock absorber box, resulting in sensitive shock absorption response. Even small-amplitude high-frequency vibrations can be effectively buffered, reducing workpiece surface ripples and roughness deviations caused by vibration, and significantly improving the surface smoothness and low-roughness forming effect of the workpiece.

[0019] Through a combination of ball joints, multiple sets of limiting cylinders, limiting rods, and buffer springs, the micro-forging head can automatically maintain a vertical reference posture when unloaded, ensuring initial machining alignment accuracy and avoiding machining defects caused by misalignment. With the help of the ball joint hinge and the limiting telescopic buffer structure, the micro-forging head can automatically adjust its tilt to adapt to the inclined surface, irregular curved surface, and uneven surface of the workpiece, achieving conformal machining. This solves the pain points of traditional rigid micro-forging heads being unable to adapt to irregular workpieces and uneven local force. The buffer spring and piston block work together to form a flexible isobaric support, ensuring that the micro-forging head and the workpiece surface always maintain uniform contact pressure, and the micro-forging force is evenly distributed. The micro-forging is uniform and consistent throughout the workpiece, effectively reducing surface roughness and improving overall machining consistency and finished product qualification rate.

[0020] The system utilizes a high-pressure air source, a pressure injection box for distribution, and multiple sets of pressure injection cylinders for independent pressure application. This structure achieves multi-point synchronous equal-pressure clamping, ensuring uniform clamping force at all stress points on the workpiece. This avoids warping, displacement, and deformation caused by single-point clamping, guaranteeing no workpiece shifting or vibration during ultrasonic micro-forging. The return spring, combined with the plug and pressure rod linkage structure, enables flexible clamping by the pressure head. This ensures stable clamping while preventing rigid pressure from damaging the surface of precision workpieces. It is suitable for clamping and fixing thin-walled and easily deformable precision workpieces. The operating table features a convex groove combined with a limit block and bolt locking structure, allowing for flexible adjustment of the installation positions of the two sets of L-shaped support seats and the pressure head. This adapts to clamping and positioning workpieces of different sizes and shapes, making the equipment highly adaptable. It eliminates the need for customized special fixtures, reducing processing tooling costs. Attached Figure Description

[0021] Figure 1 This is a schematic diagram of the overall structure of the present invention; Figure 2 This is a side view of the structure of the present invention; Figure 3 This is a schematic diagram of the multi-point isobaric fixing mechanism of the present invention; Figure 4 This is a schematic diagram of the connection structure between the shock absorption mechanism and the micro forging head of the present invention.

[0022] Figure 5 This is a cross-sectional view of the shock-absorbing box of the present invention; Figure 6 This is a cross-sectional view of the limiting cylinder and limiting rod of the present invention; Figure 7 This is a cross-sectional view of the injection cylinder of the present invention.

[0023] In the picture: 1. Machining bed; 2. Operating table; 3. Machine head; 4. Tool magazine; 5. Vibration damping mechanism; 51. Vibration damping box; 52. Pad rod; 53. Force-bearing column; 54. Adjusting plate; 55. Piston plate; 6. Isobaric micro-forging mechanism; 61. Positioning plate; 62. Ball joint; 63. Limiting cylinder; 64. Piston block; 65. Limiting rod; 66. Buffer spring; 7. Multi-point isobaric fixing mechanism; 71. L-shaped support seat; 72. Injection box; 73. Injection cylinder; 74. Pressure rod; 75. Top pressure head; 76. Plug; 77. Return spring; 78. Converter box; 79. Conduit; 8. Mounting plate; 9. Ultrasonic converter; 10. Amplitude rod; 11. Connector; 12. Mounting seat; 13. Micro-forging head; 14. Card seat; 15. Card slot. Detailed Implementation

[0024] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments.

[0025] Reference Figure 1-7 An ultrasonic machining center for ultrasonic micro-forging of low-roughness surfaces includes a machining bed 1, an operating table 2 mounted on the machining bed 1, a machine head 3 mounted on one side of the machining bed 1, a tool magazine 4 mounted on one side of the machine head 3, a mounting plate 8 mounted inside the machine head 3, an ultrasonic transducer 9 mounted at the bottom of the mounting plate 8, an amplitude transformer 10 mounted at the bottom of the ultrasonic transducer 9, a connector 11 mounted at the bottom of the amplitude transformer 10, a mounting base 12 mounted at the bottom of the connector 11, and an ultra-energy generator 16 mounted on one side of the machine head 3. The shock absorption mechanism 5 includes a shock absorption box 51, which is fixedly installed inside the machine head 3. A force-bearing column 53 is slidably connected to the bottom of the shock absorption box 51, and the force-bearing column 53 is fixedly connected to the mounting plate 8. The isobaric micro forging mechanism 6 includes a micro forging head 13, a mounting rod fixedly mounted on the bottom of the mounting base 12, and a ball joint 62 rotatably mounted on the bottom end of the mounting rod, which is fixedly connected to the micro forging head 13. The multi-point isobaric fixing mechanism 7 includes two L-shaped support seats 71, which are fixedly installed on the top of the operating table 2. A pressure injection box 72 is installed on the top of the L-shaped support seat 71, and multiple pressure heads 75 are installed on the bottom of the pressure injection box 72. A mounting bracket 14 is fixedly installed on the mounting rod. A slot 15 is provided on the mounting bracket 14. A tool changing arm is provided at the bottom of the tool magazine 4. The slot 15 is engaged with the tool changing arm.

[0026] Reference Figure 1 and Figure 4 The damping mechanism 5 also includes a piston plate 55, which is slidably mounted on the inner wall of the damping box 51. The force-bearing column 53 is fixedly connected to the piston plate 55, and the piston plate 55 is in contact with the inner wall of the damping box 51. An adjusting plate 54 is slidably connected to the inner wall of the damping box 51, and the adjusting plate 54 is in contact with the inner wall of the damping box 51. A pad rod 52 is fixedly mounted on the top of the adjusting plate 54, and the pad rod 52 is slidably connected to the top of the damping box 51. The piston plate 55, through its contact with the inner wall of the damping box 51, allows the piston to... When the stopper plate 55 moves, it can compress the air in the shock absorber box 51 and use the high-pressure gas in the shock absorber box 51 for shock absorption. When it is necessary to adjust the shock absorption intensity, a screw is set on the machine head 3. The screw is threadedly connected to the pad rod 52. Rotating the screw, through the threaded connection with the pad rod 52, can drive the adjusting plate 54 in the position of the shock absorber box 51, thereby adjusting the air pressure intensity between the adjusting plate 54 and the piston plate 55, thereby reducing the impact of the high-frequency vibration of the micro forging head 13 on the machine head 3 and the processing bed 1.

[0027] Reference Figure 4The isobaric micro-forging mechanism 6 also includes six limiting cylinders 63. The bottom of each of the six limiting cylinders 63 is slidably connected to a limiting rod 65. A positioning plate 61 is fixedly installed on the mounting rod. The limiting cylinders 63 and the limiting rods 65 are rotatably connected to the positioning plate 61 and the micro-forging head 13, respectively. A piston block 64 is slidably connected to the inner wall of the limiting cylinder 63. The piston block 64 is fixedly connected to the limiting rod 65, and a buffer spring 66 is fixedly installed on the top of the piston block 64. The top of the buffer spring 66 is fixedly connected to the top inner wall of the limiting cylinder 63. Through the sliding connection between the limiting rod 65 and the limiting cylinder 63, and the pushing action of the buffer spring 66 on the piston block 64, the micro-forging head 13 can maintain a vertical state when it is not under force. When the micro-forging head 13 contacts the processing material, it can actively adapt to the oblique micro-forging operation according to the different slope planes of the material, and make the micro-forging head 13 fully contact the material plane.

[0028] Reference Figure 2 The multi-point isobaric fixing mechanism includes multiple injection cylinders 73, each fixedly installed at the bottom of an injection box 72. The tops of the injection cylinders 73 are connected to the injection box 72. A pressure rod 74 is slidably connected to the bottom of each injection cylinder 73. A top pressure head 75 is fixedly connected to the corresponding pressure rod 74. A plug 76 is slidably connected to the inner wall of the injection cylinder 73, fitting snugly against the inner wall and fixedly connected to the pressure rod 74. A return spring 77 is fixedly installed at the bottom of the plug 76, with its bottom end connected to the injection cylinder 73. The bottom inner wall is fixedly connected, and a conversion box 78 is installed on one side of the operating table 2. Two conduits 79 are installed on the top of the conversion box 78. One end of the conduit 79 is connected to the corresponding injection box 72. The conversion box 78 is connected to an external high-pressure gas source and injects high-pressure gas into the injection box 72 through the two conduits 79. The gas in the injection box 72 is introduced into the injection cylinder 73 and squeezes the plug 76 to move downward. The plug 76 compresses the return spring 77 and drives the pressure rod 74 to move downward. The pressure head 75 presses the processing material in multiple directions with equal pressure.

[0029] Reference Figure 2 The top of the operating table 2 is provided with multiple convex grooves, and limit blocks are slidably connected in the convex grooves. The bottom of the L-shaped support 71 is provided with multiple bolts, which are threadedly connected to the limit blocks. The convex grooves can limit the limit blocks, and the L-shaped support 71 can be fixed by the threaded connection between the bolts and the limit blocks, while also facilitating the adjustment of the installation position.

[0030] Working principle: The material is placed on the operating table 2. The conversion box 78 is connected to the external high-pressure gas source. The high-pressure gas in the conversion box 78 is injected into the two injection boxes 72 through the conduit 79. The gas in the injection boxes 72 is introduced into the injection cylinder 73 and squeezes the plug 76 to move downward. The plug 76 compresses the return spring 77 and drives the pressure rod 74 to move downward. The multiple pressure heads 75 can press the material in multiple directions with equal pressure. At the same time, the multiple convex grooves on the operating table 2 can adjust the L-shaped support 71 to multiple positions, so as to press different materials. The vertical guide rails on the machining bed 1 move the machine head 3 downwards, causing the micro-forging head 13 to contact the workpiece. The ultrasonic generator 16 is activated, transmitting the ultrasonic waves to the amplitude transformer 10 via the ultrasonic transducer 9. Finally, the micro-forging head 13 performs low-roughness micro-forging on the workpiece. Simultaneously, the ultrasonic vibrations generated by the micro-forging head 13 are transmitted in reverse to the mounting plate 8, the force-bearing column 53, and the piston plate 55, causing the piston plate 55 to vibrate up and down slightly. The piston plate 55, through its contact with the inner wall of the shock-absorbing box 51, allows... When the piston plate 55 moves, it can compress the air in the shock absorber box 51 and use the high-pressure gas in the shock absorber box 51 for shock absorption. When it is necessary to adjust the shock absorption intensity, a screw is set on the machine head 3. The screw is threadedly connected to the pad rod 52. Rotating the screw, through the threaded connection with the pad rod 52, can drive the adjusting plate 54 in the position of the shock absorber box 51, thereby adjusting the air pressure intensity between the adjusting plate 54 and the piston plate 55, thereby reducing the impact of the high-frequency vibration of the micro forging head 13 on the machine head 3 and the processing bed 1. When the micro forging head 13 contacts the surface of the material being processed, the sliding connection between the limiting rod 65 and the limiting cylinder 63, and the pushing action of the buffer spring 66 on the piston block 64, allow the micro forging head 13 to maintain a vertical state when it is not under force. When the micro forging head 13 contacts the material being processed, it can actively adapt to the oblique micro forging operation according to the different slope planes of the material, and allow the micro forging head 13 to fully contact the material plane, thereby enabling the micro forging head 13 to act with equal pressure on the surface of the material being processed.

[0031] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. An ultrasonic machining center for ultrasonic micro-forging of low-roughness surfaces, comprising a machining bed (1), characterized in that, An operating table (2) is installed on the upper part of the machining bed (1). A machine head (3) is installed on one side of the machining bed (1). A tool magazine (4) is installed on one side of the machine head (3). An installation plate (8) is installed inside the machine head (3). An ultrasonic transducer (9) is installed at the bottom of the installation plate (8). An amplitude transformer (10) is installed at the bottom of the ultrasonic transducer (9). A connector (11) is installed at the bottom of the amplitude transformer (10). A mounting base (12) is installed at the bottom of the connector (11). An ultra-energy generator (16) is installed on one side of the machine head (3). The shock absorption mechanism (5) includes a shock absorption box (51), which is fixedly installed inside the machine head (3). A force-bearing column (53) is slidably connected to the bottom of the shock absorption box (51), and the force-bearing column (53) is fixedly connected to the mounting plate (8). The isobaric micro forging mechanism (6) includes a micro forging head (13), a mounting rod is fixedly mounted on the bottom of the mounting base (12), and a ball joint (62) is rotatably mounted on the bottom end of the mounting rod. The ball joint (62) is fixedly connected to the micro forging head (13). The multi-point isobaric fixing mechanism (7) includes two L-shaped support seats (71), which are fixedly installed on the top of the operating table (2), and the top of the L-shaped support seat (71) is equipped with a pressure box (72), and the bottom of the pressure box (72) is equipped with multiple pressure heads (75).

2. The ultrasonic machining center for low-roughness surfaces with ultrasonic micro-forging according to claim 1, characterized in that, The shock absorption mechanism (5) also includes a piston plate (55), which is slidably mounted on the inner wall of the shock absorption box (51), and the force-bearing column (53) is fixedly connected to the piston plate (55), and the piston plate (55) is in contact with the inner wall of the shock absorption box (51).

3. The ultrasonic machining center for low-roughness surfaces with ultrasonic micro-forging according to claim 2, characterized in that, An adjusting plate (54) is slidably connected to the inner wall of the shock-absorbing box (51). The adjusting plate (54) is in close contact with the inner wall of the shock-absorbing box (51), and a pad rod (52) is fixedly installed on the top of the adjusting plate (54). The pad rod (52) is slidably connected to the top of the shock-absorbing box (51).

4. The ultrasonic machining center for low-roughness surfaces with ultrasonic micro-forging according to claim 1, characterized in that, The isobaric micro forging mechanism (6) also includes six limiting cylinders (63), the bottom of each of the six limiting cylinders (63) is slidably connected to a limiting rod (65), a positioning plate (61) is fixedly installed on the mounting rod, and the limiting cylinders (63) and the limiting rods (65) are rotatably connected to the positioning plate (61) and the micro forging head (13) respectively.

5. The ultrasonic machining center for low-roughness surfaces with ultrasonic micro-forging according to claim 4, characterized in that, A piston block (64) is slidably connected to the inner wall of the limiting cylinder (63). The piston block (64) is fixedly connected to the limiting rod (65), and a buffer spring (66) is fixedly installed on the top of the piston block (64). The top of the buffer spring (66) is fixedly connected to the top inner wall of the limiting cylinder (63).

6. The ultrasonic machining center for low-roughness surfaces with ultrasonic micro-forging according to claim 1, characterized in that, A mounting bracket (14) is fixedly installed on the mounting rod. A slot (15) is provided on the mounting bracket (14). A tool changing arm is provided at the bottom of the tool magazine (4). The slot (15) is engaged with the tool changing arm.

7. The ultrasonic machining center for low-roughness surfaces with ultrasonic micro-forging according to claim 1, characterized in that, The multi-point isobaric fixing mechanism (7) has multiple injection cylinders (73), which are fixedly installed at the bottom of the injection box (72). The top of the injection cylinder (73) is connected to the injection box (72). The bottom of the injection cylinder (73) is slidably connected to a pressure rod (74), and the top pressure head (75) is fixedly connected to the corresponding pressure rod (74).

8. The ultrasonic machining center for low-roughness surfaces with ultrasonic micro-forging according to claim 7, characterized in that, A plug (76) is slidably connected to the inner wall of the injection cylinder (73). The plug (76) is in contact with the inner wall of the injection cylinder (73), and the plug (76) is fixedly connected to the pressure rod (74). A return spring (77) is fixedly installed at the bottom of the plug (76), and the bottom end of the return spring (77) is fixedly connected to the bottom inner wall of the injection cylinder (73).

9. The ultrasonic machining center for low-roughness surfaces with ultrasonic micro-forging according to claim 1, characterized in that, A conversion box (78) is installed on one side of the operating table (2). Two conduits (79) are installed on the top of the conversion box (78). One end of the conduit (79) is connected to the corresponding injection box (72).

10. The ultrasonic machining center for low-roughness surfaces with ultrasonic micro-forging according to claim 1, characterized in that, The top of the operating table (2) is provided with multiple convex grooves, and a limit block is slidably connected in the convex groove. The bottom of the L-shaped support base (71) is provided with multiple bolts, and the bolts are threadedly connected to the limit block.

Images