Machining fixture for hybrid transmission shift hub

Abstract

This utility model relates to the field of automotive parts processing and discloses a processing fixture for a hybrid transmission shift hub. The fixture includes a platform and a fixture assembly mounted on the platform. The fixture assembly includes a support base, a central shaft, a circumferential positioning ring, and a clamping device. The circumferential positioning ring has a C-shaped structure, forming a groove for the rear of the shift hub to engage. One end of the circumferential positioning ring has a ball-head plunger facing the groove. The processing fixture provided by this utility model utilizes the fan-shaped structure of the circumferential positioning ring and the shift hub to form a mechanical limit. Combined with the elastic preload of the ball-head plunger, a double circumferential anti-rotation mechanism is formed. This effectively resists the cutting force during processing without increasing the clamping force, completely solving the problem of circumferential rotation of the shift hub. The clamping device presses down on the shift hub, ensuring uniform force distribution, reducing stress concentration during clamping, and preventing micro-deformation of the workpiece.

Description

Technical Field

[0001] This utility model relates to the field of automotive parts processing, and in particular to a processing fixture for a hybrid transmission shift hub. Background Technology

[0002] Among the core components of a hybrid transmission, the shift hub plays a crucial role in achieving gear switching. To ensure precise alignment between the shift hub and related components, multiple holes on its head require precision drilling and tapping (see...). Figure 4 As shown in the figure, the machining process places extremely high demands on clamping and positioning accuracy and anti-circumferential rotation performance.

[0003] In existing technologies, machining fixtures for shift hubs mostly employ general-purpose positioning structures, such as fixing them by clamping the outer circumferential surface or end shoulder of the shift hub. However, the shift hub of a hybrid transmission has a more unique structural design to adapt to complex operating conditions: the head has densely distributed holes with diverse axial angles, and the tail often has a fan-shaped structure for cooperating with the shift fork (see...). Figure 5 (As shown). When using traditional fixtures for clamping, the following problems exist: On the one hand, relying on the outer peripheral surface or shoulder for positioning makes it difficult to eliminate radial and axial assembly errors of the shift hub, resulting in the machining datum of the head hole not coinciding with the design datum, affecting the positional accuracy of drilling and tapping; on the other hand, the cutting force during machining can easily cause circumferential rotation of the shift hub. Existing fixtures mostly prevent rotation by increasing the clamping force, which may not only cause extrusion deformation of the outer peripheral surface of the shift hub, but also cannot achieve directional locking for the characteristics of the tail fan-shaped structure, making it difficult to meet the requirements of high-precision machining.

[0004] Furthermore, hybrid transmissions have high requirements for lightweight and integrated components, and the balance between structural strength and machinability of the shift hub is even more stringent. Traditional fixtures are not adaptable enough and are prone to micro-deformation of the workpiece due to uneven stress distribution during clamping, which further affects the final machining quality. Therefore, there is an urgent need to design a machining fixture specifically for the fan-shaped structure at the rear of the shift hub. Utility Model Content

[0005] In view of the shortcomings of the prior art, the purpose of this utility model is to provide a machining fixture for precise positioning and reliable anti-rotation of the shift hub.

[0006] To achieve the above objectives, the present invention adopts the following technical solution:

[0007] A machining fixture for a hybrid transmission shift hub includes a platform and a fixture assembly mounted on the platform. The fixture assembly includes a support base, a central shaft vertically mounted on the support base, a circumferential positioning ring mounted on the support base and surrounding the central shaft, and several clamping devices disposed around the support base. The circumferential positioning ring has a C-shaped structure, forming a groove for the rear end of the shift hub to engage. One end of the circumferential positioning ring is provided with a ball-head plunger facing the groove. The inner hole of the shift hub is fitted onto the central shaft, and the clamping devices press the shift hub downwards against the support base.

[0008] As a further improvement to the above technical solution, the support base is a cylindrical structure and has multiple circumferentially arrayed protrusions on its top surface, which abut against the tail of the shift hub.

[0009] As a further improvement to the above technical solution, the clamping device is provided in two parts and arranged symmetrically back and forth.

[0010] As a further improvement to the above technical solution, the clamping device is a lever clamping cylinder.

[0011] As a further improvement to the above technical solution, a foolproof guide ring is provided around the central shaft via a support column.

[0012] As a further improvement to the above technical solution, the top of the central shaft is chamfered.

[0013] As a further improvement to the above technical solution, the fixture assembly is provided in two parts and arranged left and right to form a dual workstation.

[0014] As a further improvement to the above technical solution, the front and rear end surfaces of the platform are provided with a flushing structure for flushing the shift hub.

[0015] As a further improvement to the above technical solution, the flushing structure includes two upwardly extending support arms and a water-passing block disposed at the top of the two support arms. The end face of the water-passing block facing the shift hub is provided with multiple nozzles that flush water toward the shift hub.

[0016] As a further improvement to the above technical solution, the bottom of the platform is provided with two symmetrically arranged L-shaped support legs.

[0017] The beneficial effects of this utility model are as follows: The machining fixture provided by this utility model uses the circumferential positioning ring and the fan-shaped structure of the shift hub to form a mechanical limit, which, combined with the elastic preload of the ball plunger, forms a double circumferential anti-rotation mechanism. This effectively resists the cutting force during machining without increasing the clamping force, completely solving the problem of circumferential rotation of the shift hub. Furthermore, the open structure of the C-shaped circumferential positioning ring facilitates quick insertion or removal of the shift hub's tail. The elastic extension and contraction characteristics of the ball plunger can adapt to minor dimensional deviations in the fan-shaped structure, ensuring accurate and stable circumferential positioning and improving clamping efficiency. The clamping device presses down on the shift hub, ensuring uniform force distribution, reducing stress concentration during clamping, and preventing micro-deformation of the workpiece. Attached Figure Description

[0018] Figure 1 A perspective view of the machining fixture provided by this utility model.

[0019] Figure 2 A three-dimensional view showing the central axis and circumferential positioning ring positioned on the support.

[0020] Figure 3 A perspective view of the clamp pressing the shift hub against the support.

[0021] Figure 4 This is a three-dimensional view of the head structure of the shift hub. The position indicated by A in the figure is the hole to be machined.

[0022] Figure 5 This is a 3D view of the rear structure of the gear shift hub.

[0023] Explanation of main component symbols: 1-platform, 11-L-shaped support, 2-clamp assembly, 21-support base, 211-protrusion, 22-central shaft, 23-circumferential positioning ring, 231-slot, 232-ball plunger, 24-pressure clamp, 25-foolproof guide ring, 26-support column, 3-flushing structure, 31-support arm, 32-water passage block, 33-nozzle, 4-shift hub, 41-fan-shaped structure, 42-inner hole. Detailed Implementation

[0024] This utility model provides a machining fixture for the shift hub 4 of a hybrid power transmission. To make the purpose, technical solution, and effects of this utility model clearer and more explicit, the following describes this utility model in further detail with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain this utility model and are not intended to limit the scope of protection of this utility model.

[0025] Please see Figures 1 to 3This utility model provides a machining fixture for a hybrid power transmission shift hub, including a platform 1 and a fixture assembly 2 mounted on the platform 1. The fixture assembly 2 includes a support base 21, a central shaft 22 vertically mounted on the support base 21, a circumferential positioning ring 23 mounted on the support base 21 and surrounding the central shaft 22, and a plurality of clamping devices 24 mounted around the support base 21. The circumferential positioning ring 23 has a C-shaped structure, forming a groove 231 for the tail of the shift hub 4 to be inserted. One end of the circumferential positioning ring 23 is provided with a ball-head plunger 232 facing the groove 231. The inner hole 42 of the shift hub 4 is fitted onto the central shaft 22, and the clamping devices 24 press the shift hub 4 downward against the support base 21.

[0026] The inner hole 42 of the shift hub 4 is fitted onto the vertically set central shaft 22 on the support base 21. The central shaft 22 and the inner hole 42 of the shift hub 4 form a precise fit, which serves as a radial positioning reference to eliminate the radial assembly error caused by traditional peripheral surface positioning. At the same time, the bottom of the shift hub 4 is in contact with the surface of the support base 21, and the support base 21 provides stable axial support for the shift hub 4, ensuring that the machining reference coincides with the design reference.

[0027] The fan-shaped structure 41 at the rear of the shift hub 4 is inserted into the slot 231. The inner wall of the circumferential positioning ring 23 provides initial circumferential limitation for the fan-shaped structure 41. The ball-head plunger 232 at one end of the circumferential positioning ring 23 faces the slot 231. After the shift hub 4 is inserted, the ball head of the ball-head plunger 232 abuts tightly against the side of the fan-shaped structure 41. A continuous circumferential preload is applied through elasticity, further restricting the circumferential rotation of the shift hub 4 and achieving directional locking.

[0028] Several clamps 24 around the support base 21 operate synchronously, pressing the shift hub 4 downward against the support base 21. The axial pressure ensures that the shift hub 4 remains stably fitted with the support base 21, the central shaft 22 and the circumferential positioning ring 23 during the machining process, avoiding axial displacement or vibration caused by cutting force.

[0029] Finally, the CNC machine tool drills and taps the head of the shift hub 4.

[0030] The machining fixture provided by this utility model utilizes the slot 231 of the circumferential positioning ring 23 to form a mechanical limit with the fan-shaped structure 41 of the shift hub 4. Combined with the elastic preload of the ball plunger 232, a double circumferential anti-rotation mechanism is formed. This effectively resists the cutting force during machining without increasing the clamping force, completely solving the problem of circumferential rotation of the shift hub 4. Furthermore, the open structure of the C-shaped circumferential positioning ring 23 facilitates quick insertion and removal of the tail of the shift hub 4. The elastic extension and contraction characteristics of the ball plunger 232 can adapt to minor dimensional deviations in the fan-shaped structure 41, ensuring precise and stable circumferential positioning and improving clamping efficiency. The clamping device 24 presses down on the shift hub 4, ensuring uniform force distribution, reducing stress concentration during clamping, and preventing micro-deformation of the workpiece.

[0031] Because the rear end face of the shift hub 4 has multiple uneven structures, if the support base 21 were to abut against the rear end face with a flat surface, the uneven structure would result in a small actual contact area and uneven force distribution, making it difficult to achieve precise axial positioning. The support base 21 is a cylindrical structure with multiple circumferentially arrayed protrusions 211 on its top surface. The top surface of each protrusion 211 is precision-machined and has a uniform height. When these protrusions 211 abut against the rear of the shift hub 4, they avoid the uneven structure, ensuring that each protrusion 211 is in close contact with a flat surface. This design, through precise contact point distribution, effectively eliminates axial positioning deviations caused by the unevenness of the rear end face.

[0032] In this embodiment, two clamping devices 24 are provided and arranged symmetrically front to back. The two symmetrical clamping devices 24 can apply downward pressure from the front and rear sides of the shift hub 4. Combined with the multi-point support of multiple circumferential array protrusions 211 on the support base 21, the axial pressure on the shift hub 4 can be evenly distributed in the front-back direction. This avoids the shift hub 4 from tilting or micro-deformation caused by uneven pressure distribution or uneven pressure distribution, thus further ensuring the structural stability and axial positioning accuracy of the shift hub 4 during the processing.

[0033] During machining, when the shift hub 4 is subjected to cutting forces in the front-to-back direction, the two symmetrical clamps 24 can provide opposing pressures from their respective sides, effectively resisting the effects of the cutting forces and preventing the shift hub 4 from shifting or wobbling in the front-to-back direction. Combined with the circumferential positioning ring 23 and the central shaft 22, this comprehensively improves the reliability of the clamping, providing a more stable guarantee for the high-precision machining of the head holes. At the same time, this symmetrical arrangement also facilitates operation, making the clamping process simpler and more efficient.

[0034] In this embodiment, the clamping device 24 is a lever clamping cylinder. The lever clamping cylinder provides clamping force through hydraulic transmission, and its output force can be precisely controlled by the hydraulic system. The clamping force can be flexibly adjusted according to the structural strength of the shift hub 4 and the processing requirements. Compared with traditional mechanical clamping methods, it can ensure sufficient clamping force to prevent the shift hub 4 from loosening during processing, and can also avoid workpiece deformation caused by excessive pressure. It is especially suitable for the stringent requirements of hybrid transmission shift hub 4 for balancing lightweight and structural strength, further improving the safety and adaptability of clamping.

[0035] Preferably, a foolproof guide ring 25 is mounted on the periphery of the central shaft 22 via a support column 26. Located on the periphery of the central shaft 22, the foolproof guide ring 25, with its inner diameter slightly larger than the outer diameter of the shift hub 4, provides pre-guidance for the installation position of the shift hub 4 when the operator mounts it onto the central shaft 22. If the shift hub 4 shifts or tilts during installation, the inner wall of the foolproof guide ring 25 will contact the outer periphery of the shift hub 4 and correct its posture, preventing the shift hub 4 from colliding with the central shaft 22 or failing to be accurately mounted due to human error. This reduces the risk of workpiece damage during clamping and is particularly suitable for ensuring operational standardization in mass production.

[0036] Preferably, the top of the central shaft 22 is chamfered. The chamfer at the top of the central shaft 22 forms a smoothly transitioning tapered structure. In the initial stage of fitting the shift hub 4 onto the central shaft 22, the chamfer can provide precise guidance for the inner hole 42 of the shift hub 4. Even if there is a slight positional deviation in the shift hub 4 under the guidance of the foolproof guide ring 25, the chamfer can still smoothly guide the shift hub 4 into the central shaft 22 through the bevel contact, avoiding rigid collision or jamming between the inner hole 42 of the shift hub 4 and the top of the central shaft 22. This forms a dual guiding mechanism with the foolproof guide ring 25, greatly reducing the difficulty of the clamping operation.

[0037] In a preferred embodiment, the fixture assembly 2 is provided in two units, arranged side-by-side to form a dual-station configuration. The dual-station configuration allows for simultaneous processing operations; that is, the two shift hubs 4 can simultaneously undergo drilling, tapping, and other processes. Compared to a single-station configuration that processes only one workpiece at a time, the processing capacity per unit time is directly doubled, significantly improving the operating efficiency of the processing equipment. Furthermore, after completing a batch of workpieces, the two stations can simultaneously load and unload materials, avoiding the time loss caused by individually loading and unloading workpieces after processing at a single station. This significantly increases the effective processing time ratio of the equipment, making it particularly suitable for large-scale production scenarios with urgent capacity requirements.

[0038] During the machining process, a large amount of chips are generated at the head hole of the shift hub 4 during drilling and tapping, and cutting fluid adheres to its surface. Therefore, the front and rear ends of the table 1 are equipped with flushing structures 3 for rinsing the shift hub 4. The flushing structures 3 at both ends of the table 1 can cross-wash the shift hub 4 from two directions, allowing the water flow to directly reach areas prone to chip accumulation, such as the head hole and the rear fan-shaped structure 41, thoroughly removing residual chips and cutting fluid. This ensures that the shift hub 4 is clean before entering the next process.

[0039] Specifically, the flushing structure 3 includes two upward-extending support arms 31 and a water-passing block 32 disposed at the top of the two support arms 31. The end face of the water-passing block 32 facing the shift hub 4 is provided with multiple nozzles 33 that spray water onto the shift hub 4. The two upward-extending support arms 31 provide stable support for the water-passing block 32, enabling the water-passing block 32 to accurately align with the processing area of ​​the shift hub 4. The multiple nozzles 33 on the end face of the water-passing block 32 can be arranged according to the dense distribution of holes at the head of the shift hub 4 and the fan-shaped structure 41 at the tail, achieving directional flushing of different parts. The synergistic effect of the multiple nozzles 33 significantly improves the targeting of the flushing, ensuring that all key parts of the shift hub 4 are covered by water flow, avoiding cleaning dead spots.

[0040] Preferably, the bottom of the platform 1 is provided with two symmetrically arranged L-shaped support legs 11. After the platform 1 is raised, the appropriate working height makes it easier for the staff to load and unload materials, and the gap between the bottom of the platform 1 and the machine tool provides space for the flow and collection of wastewater generated by the flushing structure 3.

[0041] In the description of this utility model, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", etc., indicating the orientation or positional relationship are based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this utility model and simplifying the description, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this utility model.

[0042] In the description of this utility model, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "joining" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection, an electrical connection, or a connection that allows for communication; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model according to the specific circumstances.

[0043] It is understood that those skilled in the art can make equivalent substitutions or changes based on the technical solution and inventive concept of this utility model, and all such substitutions or changes should fall within the protection scope of this utility model.

Claims

1. A machining fixture for the shift hub of a hybrid transmission, characterized in that, The device includes a platform and a clamping assembly mounted on the platform. The clamping assembly includes a support base, a central shaft vertically mounted on the support base, a circumferential positioning ring mounted on the support base and surrounding the central shaft, and several clamping devices disposed around the support base. The circumferential positioning ring has a C-shaped structure, forming a groove for the rear end of the shift hub to engage. One end of the circumferential positioning ring is provided with a ball-head plunger facing the groove. The inner hole of the shift hub is fitted onto the central shaft, and the clamping devices press the shift hub downwards against the support base.

2. The machining fixture for the shift hub of a hybrid transmission according to claim 1, characterized in that, The support base is a cylindrical structure with multiple circumferentially arranged protrusions on its top surface, which abut against the rear of the shift hub.

3. The machining fixture for the shift hub of a hybrid transmission according to claim 1, characterized in that, The clamping device is provided in two parts and is arranged symmetrically back and forth.

4. The machining fixture for the shift hub of a hybrid transmission according to claim 3, characterized in that, The clamping device is a lever-operated clamping cylinder.

5. The machining fixture for the shift hub of a hybrid transmission according to claim 1, characterized in that, The outer periphery of the central axis is equipped with a foolproof guide ring supported by a support column.

6. The machining fixture for the shift hub of a hybrid transmission according to claim 1, characterized in that, The top of the central axis is chamfered.

7. The machining fixture for the shift hub of a hybrid transmission according to any one of claims 1-6, characterized in that, The clamping assembly has two parts, which are arranged left and right to form a dual workstation.

8. The machining fixture for the shift hub of a hybrid transmission according to claim 1, characterized in that, The front and rear ends of the platform are equipped with a flushing structure for flushing the shift hub.

9. The machining fixture for the shift hub of a hybrid transmission according to claim 8, characterized in that, The flushing structure includes two upward-extending support arms and a water-passing block disposed at the top of the two support arms. The end face of the water-passing block facing the shift hub is provided with multiple nozzles that flush water toward the shift hub.

10. The machining fixture for the shift hub of a hybrid transmission according to claim 1, characterized in that, The bottom of the platform is provided with two symmetrically arranged L-shaped support legs.

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