Transmission lower support machining clamp
By dividing the machining area on the fixture body and setting up positioning structures and clamping devices, the problem of frequent fixture changes in the machining of the lower gearbox bracket was solved, enabling the same CNC program to complete two machining processes, thus improving production efficiency and workpiece stability.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- GUANGZHOU AUTOMIBILE GRP MOTOR
- Filing Date
- 2025-05-13
- Publication Date
- 2026-05-05
AI Technical Summary
The machining of the lower gearbox bracket requires two processes with different workpiece structures, resulting in frequent fixture changes, increased labor load and production time, and reduced production efficiency.
Design a gearbox lower bracket machining fixture. The fixture body is divided into a first machining area and a second machining area, with a first positioning structure and a second positioning structure respectively. It is equipped with a clamping device and a clamping device, and the two machining processes are completed through the same CNC program.
Reduce fixture changeover time, lower labor load, improve production efficiency, ensure workpiece stability during processing, and prevent misalignment.
Smart Images
Figure CN224196367U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the field of machining fixture equipment technology, and more specifically, to a machining fixture for a lower support of a transmission. Background Technology
[0002] During the machining process of parts, machining fixtures are required to clamp the workpiece and fix its position, preventing displacement due to forces during machining and resulting in machining defects. The working principle of a machining fixture is mainly to position the workpiece within the fixture using locating elements, ensuring its position remains constant throughout the machining process. Clamping devices provide sufficient clamping force to keep the workpiece in the correct position. Tool setting and guiding elements ensure the correct tool position during machining. Connecting elements guarantee the relative positional relationship between the fixture and the machine tool, ensuring machining accuracy. The fixture body connects all components into a unified whole, ensuring the stability and accuracy of the entire fixture. The machining process of a gearbox lower bracket machining fixture requires at least two operations. The workpiece structure differs in each operation, and the requirements for the fixture structure also differ. Therefore, at least two different fixture structures are used to clamp the workpiece during machining, and CNC machining is performed. However, in actual machining, changing different fixtures requires re-setting the tool, significantly extending the machining time, increasing the workload of workers, and severely impacting production cycle time. At the same time, since some of the structures used to fix the workpiece need to be processed in the first process, the workpiece is prone to shifting due to insecure fixing during the first process, resulting in waste material. Utility Model Content
[0003] To solve the above-mentioned technical problems, this utility model provides a gearbox lower bracket machining fixture, which can complete the clamping and processing of the workpiece in two processes using a single fixture, greatly improving the processing efficiency of the parts. After one rotation, the finished parts can be produced by automatic CNC machining, reducing production costs. It can also provide additional clamping force to prevent the workpiece from shifting due to the lack of a fixing structure when the fixing hole has not yet been machined.
[0004] To solve the above-mentioned technical problems, the technical solution adopted by this utility model is as follows: a gearbox lower bracket machining fixture, including a fixture body, a first processing area and a second processing area are provided on the upper surface of the fixture body, a first positioning structure is provided in the first processing area, a second positioning structure is provided in the second processing area, a clamping device for clamping the workpiece is provided next to both the first and second positioning structures, and a clamping device for providing clamping force is also provided next to the first positioning structure. The first positioning structure includes a support column and a positioning pin. The support column, positioning pin and clamping device are all fixedly installed on the fixture body. The positioning pin is aligned with the process hole of the workpiece. The support column is arranged according to the shape of the workpiece. The upper surface of the support column abuts against the bottom surface of the workpiece. A side plate is formed by protrusion at the edge of the upper surface of the support column away from the workpiece. The side plate abuts against the side wall surface of the workpiece.
[0005] In this technical solution, the fixture body is used to connect and fix other components and to securely mount them on the machine tool. During workpiece machining, the workpiece's structure itself can obstruct the machine tool's cutting tool, preventing it from reaching certain positions for machining. Therefore, at least two machining operations are required. The structure and orientation of the parts differ in each of the two operations, necessitating at least two sets of fixtures. Changing fixtures mid-operation increases manufacturing costs and prevents the CNC machine tool from using the same CNC program, requiring at least two separate CNC programs, significantly increasing the workload. Furthermore, each of the two fixtures requires at least two tool settings, increasing the time needed for tool setting, slowing down the work cycle, and impacting production efficiency. To address this issue, the fixture body is divided into two areas: a first machining area and a second machining area, corresponding to two different machining operations. Since the workpiece's orientation and structure change in both operations, separate first and second positioning structures are required to position the workpiece in different operations. After the workpiece is installed on the first or second positioning structure, the clamping device is activated to clamp the workpiece onto the first or second positioning structure, thus fixing the workpiece in place. After fixing, the relative positions of the workpiece on the first and second positioning structures are determined. During machining, the cutting tool can move from the first to the second positioning structure along a defined trajectory, allowing the CNC machine tool to complete two different machining processes using the same CNC program, thereby obtaining the product. Both the first and second positioning structures fix the workpiece using fixing holes. However, some fixing holes need to be machined in the first process, which means the first positioning structure may lack fixing holes and cannot guarantee the workpiece's stability during machining. Therefore, a clamping device is needed to provide additional clamping force to ensure the workpiece remains stable during machining. In use, the original workpiece is first installed on the first positioning structure located in the first machining area. The clamping device is then used to apply clamping force to the workpiece, and the clamping device is activated to clamp the original workpiece for the first machining process. After the first process is completed, a semi-finished workpiece is produced. Then, the clamping device is controlled to release the clamp on the semi-finished workpiece and loosen the clamping device. The semi-finished workpiece located on the first positioning structure is removed and installed on the second positioning structure. Then, a new original workpiece is taken out and installed on the first positioning structure. After that, the clamping device is operated again to clamp the original workpiece and the semi-finished workpiece. The CNC machine tool is started, and under the control of the same CNC program, the machine tool completes the processing of the original workpiece and the semi-finished workpiece respectively, finally producing the finished workpiece and the new semi-finished workpiece. The above workflow is then repeated to continuously produce finished workpieces.The locating pin determines the position of the workpiece by inserting it into the locating hole. Since the workpiece surface is irregular, it is difficult to achieve stable placement by placing it directly on the fixture body. The support column supports the workpiece, allowing it to be suspended in the air to accommodate its irregular shape. The upper surface of the support column has a raised side plate, which, by abutting against the side wall of the workpiece, restricts its horizontal movement, thus providing auxiliary positioning.
[0006] Preferably, the clamping device includes a fixed base and a clamping rod. The fixed base is fixedly mounted on the fixture body and has a threaded hole. The axial direction of the threaded hole is towards the workpiece. The outer circumferential surface of the clamping rod is provided with threads, and the clamping rod is inserted into the threaded hole and threadedly connected to it.
[0007] Preferably, the fixture body is further provided with a receiving hole, which is located between the support column and the positioning pin, and the workpiece can be inserted into the receiving hole.
[0008] Preferably, the second positioning structure includes a second positioning pin and a second support column. Both the second positioning pin and the second support column are fixedly installed on the fixture body. At least two second positioning pins are provided, namely a cylindrical pin and a diamond pin. The upper surface of the second support column is a support surface, which abuts against the bottom surface of the workpiece. The height of the second support column is the same as the height at which the bottom surface of the workpiece abuts against the support surface. The positions of the second positioning pin and the second support column are set according to the shape of the workpiece.
[0009] Preferably, the clamping device includes a telescopic member and a clamping rod. The telescopic member is fixedly installed on the fixture body, with the telescopic end of the telescopic member facing upward. The clamping rod is fixedly installed on the telescopic rod of the telescopic member, with the end of the clamping rod extending above the workpiece located on the first positioning structure or the second positioning structure. The shape of the end of the clamping rod matches the shape of the workpiece surface.
[0010] Preferably, the clamping rod includes a connecting part and a clamping part. The clamping part is a rod-shaped structure extending from the connecting part. The connecting part is connected to the telescopic end of the telescopic member. At least two clamping parts are provided. At least two first positioning structures and at least two second positioning structures are provided respectively. The two clamping parts extend above the workpiece installed on different first positioning structures or second positioning structures.
[0011] Preferably, the top of the telescopic end of the telescopic component has a long strip-shaped cross-section, and the clamping rod is provided with a long strip-shaped mounting hole, which is inserted into the top of the telescopic end of the telescopic component.
[0012] Preferably, the telescopic member is provided with a rotating device for driving the telescopic rod to rotate.
[0013] Preferably, the telescopic component is a telescopic electric cylinder, and a controller is also installed on the clamp body. The controller is electrically connected to the telescopic component, and the controller is provided with an interface through which it is connected to an external computer.
[0014] Preferably, the clamp body is further provided with fixing holes.
[0015] Compared with existing technologies, the beneficial effects of this technical solution are: by dividing the fixture body into a first machining area and a second machining area, the same fixture can meet the needs of different processes, reducing the time required for fixture changes. This allows CNC machine tools to complete two processes using the same CNC program, reducing the workload of operators and improving production efficiency. Furthermore, different first and second positioning structures can be used to adapt to the different positioning requirements of two different processes. The inclusion of a clamping device provides additional clamping force to prevent workpiece displacement during machining due to the lack of a fixing structure before the workpiece has been machined with a fixing hole. Attached Figure Description
[0016] Figure 1 This is a perspective view of the machining fixture for the lower gearbox bracket of this utility model;
[0017] Figure 2 yes Figure 1 Enlarged view of point A in the middle;
[0018] Figure 3 yes Figure 1 Enlarged view of point B in the middle.
[0019] In the attached diagram: 1. Fixture body; 2. First positioning structure; 3. Second positioning structure; 4. Clamping device; 11. Fixing hole; 12. Accommodating hole; 21. Support column; 22. Positioning pin; 23. Clamping device; 24. Fixing base; 25. Clamping rod; 26. Side plate; 31. Second positioning pin; 32. Second support column; 41. Telescopic component; 42. Clamping rod; 43. Mounting hole. Detailed Implementation
[0020] The accompanying drawings are for illustrative purposes only and should not be construed as limiting this patent. To better illustrate this embodiment, some components in the drawings may be omitted, enlarged, or reduced, and do not represent the actual dimensions of the product. It is understandable to those skilled in the art that some well-known structures and their descriptions may be omitted in the drawings. The positional relationships described in the drawings are for illustrative purposes only and should not be construed as limiting this patent.
[0021] In the accompanying drawings of this utility model, the same or similar reference numerals correspond to the same or similar components. In the description of this utility model, it should be understood that if terms such as "upper," "lower," "left," "right," "long," and "short" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, they are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or component referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, the terms used to describe positional relationships in the drawings are only for illustrative purposes and should not be construed as limiting this patent. For those skilled in the art, the specific meaning of the above terms can be understood according to the specific circumstances.
[0022] The technical solution of this utility model will be further described in detail below through specific embodiments and with reference to the accompanying drawings:
[0023] Example 1
[0024] like Figure 1 , 2As shown, a gearbox lower bracket machining fixture includes a fixture body 1. The upper surface of the fixture body 1 is provided with a first machining area and a second machining area. A first positioning structure 2 is provided in the first machining area, and a second positioning structure 3 is provided in the second machining area. Clamping devices 4 for clamping workpieces are provided beside both the first and second positioning structures 2 and 3. A clamping device 23 for providing clamping force is also provided beside the first positioning structure 2. The first positioning structure 2 includes a support column 21 and a positioning pin 22. The support column 21, positioning pin 22, and clamping device 23 are all fixedly installed on the fixture body 1. The positioning pin 22 is aligned with the process hole of the workpiece. The support column 21 is arranged according to the shape of the workpiece, and its upper surface abuts against the bottom surface of the workpiece. A side plate 26 is formed by protrusions on the upper surface of the support column 21 away from the edge of the workpiece, and the side plate 26 abuts against the side wall of the workpiece. The fixture body 1 is used to connect and fix other components and to fix them on a machine tool. When machining a workpiece, its structure can obstruct the machine tool's cutting tool, preventing it from reaching certain areas for machining. Therefore, at least two machining operations are required. Since the workpiece's structure and orientation differ between the two operations, at least two sets of fixtures are necessary. Changing fixtures mid-operation increases manufacturing costs and prevents the CNC machine from using the same program, requiring at least two separate CNC programs, significantly increasing the workload. Furthermore, each fixture requires at least two tool settings, increasing setup time, slowing down the workflow, and impacting production efficiency. To address this, the fixture body 1 is divided into two areas: a first machining area and a second machining area, corresponding to two different machining operations. Because the workpiece's orientation and structure change between the two operations, a first positioning structure and a second positioning structure 3 are required to position the workpiece in different operations. After the workpiece is installed on the first positioning structure or the second positioning structure 3, the clamping device 4 is activated to clamp the workpiece on the first positioning structure or the second positioning structure 3, thereby fixing the workpiece. After fixing, the relative positions of the workpiece on the first positioning structure and the workpiece on the second positioning structure 3 are determined. During machining, the cutting tool can move from the first positioning structure to the second positioning structure 3 along a determined trajectory, allowing the CNC machine tool to complete two different machining processes using the same CNC program, thus obtaining the product. Both the first positioning structure and the second positioning structure 3 fix the workpiece through fixing holes on the workpiece. However, some fixing holes need to be machined in the first process, which will result in the first positioning structure lacking fixing holes and thus failing to guarantee the stability of the workpiece during machining. Therefore, a clamping device 23 is required to provide external clamping force to the workpiece to ensure its stability during machining.In operation, the original workpiece is first mounted on the first positioning structure in the first processing area. The clamping device 23 is operated to apply clamping force to the workpiece, and then the clamping device 4 is activated to clamp the original workpiece for the first processing step. After the first processing step is completed, a semi-finished workpiece is produced. Then, the clamping device 4 is controlled to release the clamp on the semi-finished workpiece and the clamping device 23 is released. The semi-finished workpiece is removed from the first positioning structure and mounted on the second positioning structure 3. A new original workpiece is then removed and mounted on the first positioning structure. The clamping device 4 is then operated again to clamp both the original and semi-finished workpieces. The CNC machine tool is started, and under the control of the same CNC program, the machine tool completes the processing of both the original and semi-finished workpieces, ultimately producing a finished workpiece and a new semi-finished workpiece. This process is repeated to continuously produce finished workpieces. Before machining, positioning holes are pre-drilled in the workpiece. Positioning pins 22 can be inserted into the positioning holes in the workpiece to determine its position. Since the surface shape of the workpiece is irregular, it is difficult to achieve stable placement by placing it directly on the fixture body 1. Support columns 21 are used to support the workpiece, making the workpiece suspended in the air to adapt to the irregular shape of the workpiece surface. The upper surface of the support column 21 has a raised side plate 26. By having the side plate 26 abut against the side wall of the workpiece, the horizontal movement of the workpiece is restricted, which plays an auxiliary positioning role.
[0025] like Figure 2 As shown, the clamping device 23 includes a fixed base 24 and a clamping rod 25. The fixed base 24 is fixedly mounted on the fixture body 1. The fixed base 24 has a threaded hole with its axial direction facing the workpiece. The clamping rod 25 has threads on its outer circumferential surface and is inserted into the threaded hole and threadedly connected to it. After the workpiece is installed on the first positioning structure 2, the clamping rod 25 is turned so that it presses against the outer surface of the workpiece, forming a clamping effect together with the first positioning structure 2, thereby fixing the workpiece and ensuring its stability during processing.
[0026] like Figure 2 As shown, the fixture body 1 is also provided with a receiving hole 12, which is located between the support column 21 and the positioning pin 22, and the workpiece can be extended into the receiving hole 12. By providing the receiving hole 12 to allow the workpiece to extend into it, the space can be fully utilized, the height of the workpiece during processing can be reduced, and the distance that the tool needs to move in the vertical direction can be reduced.
[0027] Example 2
[0028] This embodiment is similar to Embodiment 1 above, except that, as Figure 3As shown, the second positioning structure 3 includes a second positioning pin 31 and a second support column 32. Both the second positioning pin 31 and the second support column 32 are fixedly installed on the fixture body 1. At least two second positioning pins 31 are provided, one being a cylindrical pin and the other a diamond-shaped pin. The upper surface of the second support column 32 is a support surface, which abuts against the bottom surface of the workpiece. The height of the second support column 32 is the same as the height at which the bottom surface of the workpiece abuts against the support surface. The positions of the second positioning pins 31 and the second support column 32 are set according to the shape of the workpiece. After completing the first processing step, the semi-finished workpiece is processed to form a new hole-like structure, which can serve as a new positioning hole. Therefore, in the second positioning structure 3, only at least two second positioning pins 31 are needed to completely fix the position of the semi-finished workpiece in the horizontal direction, without the need for an additional clamping device 23 or a structure similar to a side plate 26 on the second support column 32. The second support column 32 is used to support the semi-finished workpiece.
[0029] Example 3
[0030] This embodiment is similar to Embodiment 1 above, except that, as Figure 1 As shown, the clamping device 4 includes a telescopic member 41 and a clamping rod 42. The telescopic member 41 is fixedly installed on the fixture body 1, with its telescopic end facing upwards. The clamping rod 42 is fixedly installed on the telescopic rod of the telescopic member 41, with the end of the clamping rod 42 extending above the workpiece located on the first positioning structure 2 or the second positioning structure 3. The shape of the end of the clamping rod 42 matches the shape of the workpiece surface. When the telescopic member 41 is in the extended state, there is a certain distance between the clamping rod 42 and the first positioning structure 2 or the second positioning structure 3. At this time, the clamping rod 42 is in the open state, and the operator can take out or place the workpiece located on the first positioning structure 2 or the second positioning structure 3. After the workpiece is placed, the tooling operator controls the telescopic member 41 to retract, and the telescopic member 41 drives the clamping rod 42 to press against the workpiece, thereby clamping the workpiece. The shape of the end of the clamping rod 42 is set according to the shape of the workpiece surface to match the two, ensuring that the clamping rod 42 is in stable contact with the workpiece and will not slip accidentally.
[0031] like Figure 1 As shown, the clamping rod 42 includes a connecting part and a clamping part. The clamping part is a rod-shaped structure extending from the connecting part. The connecting part is connected to the telescopic end of the telescopic member 41. At least two clamping parts are provided, and at least two first positioning structures 2 and two second positioning structures 3 are each provided. The two clamping parts extend above the workpieces mounted on different first positioning structures 2 or second positioning structures 3. By providing at least two clamping parts on a single clamping rod 42, a single clamping device 4 can clamp at least two workpieces simultaneously, improving the utilization rate of the telescopic member 41 and reducing the operating cost.
[0032] like Figure 1 As shown, the top of the telescopic end of the telescopic component 41 has a long strip-shaped cross-section, and the clamping rod 42 is provided with a long strip-shaped mounting hole 43, which is inserted into the top of the telescopic end of the telescopic component 41. During the process of clamping the workpiece with the clamping rod 42, due to the influence of the external shape of the workpiece, the workpiece may exert a lateral force on the clamping rod 42 after it comes into contact with the clamping rod 42. If the top of the telescopic end of the telescopic component 41 and the mounting hole 43 on the clamping rod 42 are both set as conventional circles, the clamping rod 42 may deflect under the action of lateral force, affecting the clamping effect. Therefore, it is necessary to set the cross-section of the top of the telescopic end of the telescopic component 41 and the mounting hole 43 on the clamping rod 42 as long strips to counteract the lateral force that the clamping rod 42 may receive and to prevent the clamping rod 42 from deflecting.
[0033] like Figure 1 As shown, the telescopic member 41 is equipped with a rotating device that drives the telescopic rod to rotate. The telescopic end of the telescopic member 41 can rotate to drive the clamping rod 42 to rotate, thereby causing the clamping rod 42 to rotate out from above the first positioning structure 2 or the second positioning structure 3, thus ensuring that the space above the first positioning structure 2 and the second positioning structure 3 remains unobstructed, facilitating the installation or removal of workpieces by the operator. After the workpiece is installed on the first positioning structure 2 or the second positioning structure 3, the telescopic end of the telescopic member 41 is rotated to above the first positioning structure 2 or the second positioning structure 3 to clamp the workpiece.
[0034] like Figure 1 As shown, the telescopic component 41 is a telescopic electric cylinder. A controller is also installed on the fixture body 1, and the controller is electrically connected to the telescopic component 41. The controller has an interface, which connects to the machine tool via a data cable. The machine tool's operation is controlled by a CNC program, and the operation of the telescopic rod 41 needs to coordinate with the machine tool's operation. The controller is connected to the machine tool via a data cable, and can control the telescopic component 41 according to the CNC program in the machine tool, realizing automatic clamping and releasing of the workpiece by the clamping device 4. This eliminates the need for manual operation and reduces the possibility of machining errors due to human error.
[0035] like Figure 1 As shown, the fixture body 1 is also provided with a fixing hole 11. The fixture body 1 can be fixedly installed on the machine tool for machining operations using fastening bolts through the fixing hole 11.
[0036] Obviously, the above embodiments of this utility model are merely examples for clearly illustrating this utility model, and are not intended to limit the implementation of this utility model. Those skilled in the art can make other variations or modifications based on the above description. It is neither necessary nor possible to exhaustively describe all embodiments here. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this utility model should be included within the protection scope of the claims of this utility model.
Claims
1. A machining fixture for a lower support of a transmission, characterized in that, The fixture includes a fixture body (1), the upper surface of which is provided with a first processing area and a second processing area. A first positioning structure (2) is provided in the first processing area, and a second positioning structure (3) is provided in the second processing area. A clamping device (4) for clamping the workpiece is provided next to both the first positioning structure (2) and the second positioning structure (3). A clamping device (23) for providing clamping force is also provided next to the first positioning structure (2). The first positioning structure (2) includes a support column (21). The positioning pin (22), the support column (21), the positioning pin (22) and the clamping device (23) are all fixedly installed on the fixture body (1). The positioning pin (22) is aligned with the process hole of the workpiece. The support column (21) is arranged according to the shape of the workpiece. The upper surface of the support column (21) abuts against the bottom surface of the workpiece. A side plate (26) is formed by protruding on the upper surface of the support column (21) away from the edge of the workpiece. The side plate (26) abuts against the side wall of the workpiece.
2. The machining fixture for a lower gearbox bracket according to claim 1, characterized in that, The clamping device (23) includes a fixed seat (24) and a clamping rod (25). The fixed seat (24) is fixedly installed on the fixture body (1). The fixed seat (24) has a threaded hole with the axial direction of the workpiece. The clamping rod (25) has a thread on its outer circumferential surface. The clamping rod (25) is inserted into the threaded hole and threadedly connected to it.
3. The machining fixture for a lower transmission bracket according to claim 1, characterized in that, The fixture body (1) is also provided with a receiving hole (12), which is located between the support column (21) and the positioning pin (22), and the workpiece can be inserted into the receiving hole (12).
4. The machining fixture for a lower gearbox bracket according to claim 1, characterized in that, The second positioning structure (3) includes a second positioning pin (31) and a second support column (32). The second positioning pin (31) and the second support column (32) are both fixedly installed on the fixture body (1). There are at least two second positioning pins (31), which are cylindrical pins and diamond pins, respectively. The upper surface of the second support column (32) is a support surface, which abuts against the bottom surface of the workpiece. The height of the second support column (32) is the same as the height of the bottom surface of the workpiece abutting against the support surface. The positions of the second positioning pin (31) and the second support column (32) are set according to the shape of the workpiece.
5. A machining fixture for a lower transmission bracket according to claim 1, characterized in that, The clamping device (4) includes a telescopic member (41) and a clamping rod (42). The telescopic member (41) is fixedly installed on the fixture body (1), with the telescopic end of the telescopic member (41) facing upward. The clamping rod (42) is fixedly installed on the telescopic rod of the telescopic member (41), with the end of the clamping rod (42) extending above the workpiece located on the first positioning structure (2) or the second positioning structure (3). The shape of the end of the clamping rod (42) matches the shape of the surface of the workpiece.
6. A machining fixture for a lower transmission bracket according to claim 5, characterized in that, The clamping rod (42) includes a connecting part and a clamping part. The clamping part is a rod-shaped structure extending from the connecting part. The connecting part is connected to the telescopic end of the telescopic member (41). At least two clamping parts are provided. At least two first positioning structures (2) and two second positioning structures (3) are provided respectively. The two clamping parts extend above the workpiece installed on different first positioning structures (2) or second positioning structures (3).
7. A machining fixture for a lower transmission bracket according to claim 5, characterized in that, The top of the telescopic end of the telescopic component (41) has a long strip-shaped cross-section, and the clamping rod (42) is provided with a long strip-shaped mounting hole (43), which is inserted into the top of the telescopic end of the telescopic component (41).
8. A machining fixture for a lower transmission bracket according to claim 5, characterized in that, The telescopic member (41) is provided with a rotating device that drives the telescopic rod to rotate.
9. A machining fixture for a lower transmission bracket according to claim 5, characterized in that, The telescopic component (41) is a telescopic electric cylinder. A controller is also installed on the clamp body (1). The controller is electrically connected to the telescopic component (41). The controller is provided with an interface and is connected to an external computer through the interface.
10. A machining fixture for a lower transmission bracket according to claim 1, characterized in that, The clamp body (1) is also provided with a fixing hole (11).