Split compensation tooling for controlling heat treatment distortion of a lock pin type synchronizer hub

Abstract

The utility model discloses a kind of control lock pin type synchronizer gear hub heat treatment distortion split type compensation tool, solve the existing lock pin type synchronizer, after heat treatment, it is prone to greater heat treatment distortion, cause the size accuracy of the cumulative total deviation Fp of spline pitch is poor technical problem.This control lock pin type synchronizer gear hub heat treatment distortion split type compensation tool, including with the N compensation units of one-to-one correspondence of N recesses of the synchronizer gear hub to be heat treated, N≥3;Each compensation unit includes grabbing assembly, 2 support assemblies and compensation assembly;The lower end of grabbing assembly is fixedly connected with the upper end of compensation assembly, and the clamping of external clamp is respectively abutted on the outer side wall of N grabbing assembly when grabbing;Compensation assembly is cuboid structure, its size is compatible with the recess of lock pin type synchronizer gear hub;Support assembly is symmetrically connected on the two end side walls of compensation assembly along width direction, and the inner wall of external spline of lock pin type synchronizer gear hub is abutted when grabbing 2 support assemblies.

Description

Technical Field

[0001] This utility model specifically relates to a split-type compensation fixture for controlling the heat treatment distortion of the tooth hub of a locking pin synchronizer. Background Technology

[0002] The synchronizer assembly is a key subassembly in an automotive transmission, and the synchronizer hub is a crucial component within it. Its manufacturing quality and precision directly impact the transmission's shifting performance. As the automotive industry continues to evolve, manufacturers are demanding higher shifting performance, thus requiring greater precision in the synchronizer assembly's dimensions. In light and heavy-duty truck transmissions, the most common synchronizer assembly is the locking pin type. For example... Figure 1 , Figure 2 As shown, the existing locking pin type synchronizer hub includes an external spline 01, a connecting ring 02, and an internal spline 03 arranged coaxially. The outer wall of the connecting ring 02 is fixedly connected to the inner wall of the external spline 01, and the inner wall of the connecting ring 02 is fixedly connected to the outer wall of the internal spline 03. The external spline 01, the internal spline 03, and the connecting ring 02 form an annular groove on their end faces. The circumference of the external spline 01 and the connecting ring 02 is generally provided with multiple grooves 04 in the radial direction for installing springs and positioning pins. This structure is prone to large heat treatment distortion after heat treatment, which causes the cumulative total deviation Fp of the spline tooth pitch to deteriorate in dimensional accuracy.

[0003] Chinese patent CN106337885A discloses a "self-locking pin for a synchronizer in a manual transmission". This invention uses a high-precision, small injection-molded snap-fit ​​base with an innovative bidirectional spiral coil spring to provide spring force. It has a compact structure, is easy to install and position, and can ensure that there is appropriate self-locking force after the synchronizer sleeve is engaged in gear to prevent the transmission from skipping gears.

[0004] However, the above technical solutions also have the technical problem that the locking pin synchronizer is prone to large heat treatment distortion after heat treatment, which leads to a decrease in the dimensional accuracy of the cumulative total deviation Fp of the spline tooth pitch. Utility Model Content

[0005] The purpose of this invention is to solve the technical problem that existing locking pin synchronizers are prone to large heat treatment distortion after heat treatment, which leads to a decrease in the dimensional accuracy of the cumulative total deviation Fp of the spline tooth pitch. The invention provides a split-type compensation fixture for controlling the heat treatment distortion of the tooth hub of the locking pin synchronizer.

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

[0007] A split-type compensation fixture for controlling the distortion of the synchronizer hub during heat treatment is characterized by: including N compensation units corresponding one-to-one with N grooves of the synchronizer hub to be heat treated, where N≥3; each compensation unit includes a gripping component, two support components and a compensation component.

[0008] The lower end of the gripping component is fixedly connected to the upper end of the compensation component. During gripping, the external clamps abut against the outer walls of the N gripping components respectively.

[0009] The compensation component has a cuboid structure, and its dimensions are adapted to the groove of the locking pin synchronizer hub.

[0010] The support components are symmetrically connected to the two end sidewalls of the compensation component along the width direction, and the bottom of the support components fits into the bottom of the groove of the locking pin synchronizer hub ring groove to support the compensation component that extends into the groove. When gripping, the two support components abut against the inner wall of the outer spline of the locking pin synchronizer hub.

[0011] Furthermore, the grasping component is integrally formed with two support components and a compensation component.

[0012] Furthermore, the grasping component has a cuboid structure.

[0013] Furthermore, the support component has a cuboid structure.

[0014] Furthermore, the width d of the compensation unit is 0.1-1.5 mm smaller than the width D of the groove in the locking pin synchronizer hub, and the length w is 0.2-2 mm larger than the length W of the groove in the locking pin synchronizer hub.

[0015] Furthermore, the height h of the compensation component is 0.1-1.5 mm higher than the height H of the external spline of the locking pin synchronizer hub.

[0016] Furthermore, the width of the gripping component is the same as the width of the compensation component, and the height s of the gripping component is greater than 10mm.

[0017] Furthermore, the length, width, and height of the support component are all less than 10mm.

[0018] Furthermore, N = 3.

[0019] Furthermore, the compensation unit is made of carburized steel.

[0020] The beneficial effects of this utility model are:

[0021] 1. The N compensation units in this utility model form a split compensation fixture. Each compensation unit is divided into an upper gripping component, two side support components and a lower compensation component. Only the lower end face of the support component is in direct contact with the upper end face of the connecting ring, which solves the problem of insufficient effective hardening layer depth of the contact surface between the part and the fixture after the compensation fixture is used.

[0022] 2. The two-sided support components of this utility model are rectangular structures. The height of the compensation component is 0.1-1.5mm higher than that of the external spline to ensure that the compensation component fills the groove and avoids the problem of large heat treatment distortion that easily occurs in the locking pin synchronizer after heat treatment.

[0023] 3. The split-type compensation fixture of this utility model can reduce the distortion of the spline of the locking pin synchronizer hub by 20%-80% during the heat treatment process and improve the dimensional accuracy of the parts. Attached Figure Description

[0024] Figure 1 This is a structural schematic diagram of an existing locking pin type synchronizer hub, where D is the width of the groove in the locking pin type synchronizer hub and W is the length of the groove in the locking pin type synchronizer hub.

[0025] Figure 2 yes Figure 1 Top view;

[0026] Appendix Figures 1 to 2 The marking description is as follows:

[0027] 01-External spline, 02-Connecting ring, 03-Internal spline, 04-Groove;

[0028] Figure 3 This is a schematic diagram of the compensation unit in an embodiment of the present invention;

[0029] Figure 4 This is a front view of the compensation unit in an embodiment of this utility model, where d is the width of the compensation unit;

[0030] Figure 5 yes Figure 4 The right view shows that w is the length of the compensation unit, h is the height of the compensation component, and s is the height of the gripping component.

[0031] Figure 6 yes Figure 4 Top view;

[0032] Figure 7 This is a schematic diagram of the compensation unit installed on the existing locking pin type synchronizer hub in an embodiment of this utility model;

[0033] Figure 8 This is a top view of the compensation unit installed on the existing locking pin type synchronizer hub in an embodiment of this utility model.

[0034] Appendix Figures 3 to 8 The marking description is as follows:

[0035] 1-Grab component, 2-Support component, 3-Compensation component. Detailed Implementation

[0036] A split-type compensation fixture for controlling heat treatment distortion of a locking pin type synchronizer hub includes three compensation units corresponding one-to-one with three grooves 04 of the synchronizer hub to be heat treated; such as Figure 3 As shown, each compensation unit includes a gripping component 1, two support components 2, and a compensation component 3. The gripping component 1 is a cuboid structure, with its lower end fixed to the upper end of the compensation component 3. During gripping, the external clamps abut against the outer walls of the three gripping components 1. The compensation component 3 is a cuboid structure, and its dimensions are adapted to the groove 04 of the locking pin synchronizer hub. The support components 2 are cuboid structures, with one end of each support component 2 fixed to the side wall of the compensation component 3. The support components 2 are symmetrically connected to the two side walls of the compensation component 3 along the width direction. The support components 2 are placed on the upper surface of the locking pin synchronizer hub connecting ring 02, and the upper surface of the synchronizer hub connecting ring 02 provides support to the support components 2. During gripping, the two support components 2 abut against the inner wall of the outer spline 01 of the synchronizer hub to prevent the compensation unit from falling off.

[0037] like Figures 4 to 6 As shown, the gripping component 1 is integrally formed with two support components 2 and a compensation component 3. The height s of the gripping component 1 is greater than 10mm; the length, width, and height of the support components 2 are all less than 10mm, which reduces the contact area between the inner wall of the outer spline 01 and the support components 2, ensuring the carburizing effect; the compensation component 3 has the same width as the gripping component 1, the width d of the compensation unit is 0.1-1.5mm smaller than the width D of the locking pin synchronizer hub groove 04, the length w of the compensation unit is 0.2-2mm larger than the length W of the locking pin synchronizer hub groove 04, and the height h is 0.1-1.5mm higher than the height H of the locking pin synchronizer hub outer spline 01. The compensation unit is made of the same carburized steel as the locking pin synchronizer hub and is machined from a single piece of steel.

[0038] In this embodiment, the three compensation units form a split compensation fixture. After heat treatment using the three compensation units, the thermal distortion at the groove 04 of the locking pin synchronizer hub is smaller than that without the compensation fixture, thereby reducing the cumulative total deviation Fp of the overall tooth pitch of the locking pin synchronizer hub spline and improving its spline accuracy. A certain gap is left between the three compensation units and the groove 04 of the locking pin synchronizer hub to ensure effective contact between the locking pin synchronizer hub and each compensation unit after heat treatment, so that the hardened layer depth meets the product requirements.

[0039] The specific processing procedure of this utility model, based on the above-mentioned split-type compensation fixture for controlling heat treatment distortion of the locking pin type synchronizer hub, is as follows:

[0040] 1. Install compensation unit:

[0041] like Figure 7 , Figure 8As shown, three compensation units are respectively installed in the three grooves 04 of the lock pin synchronizer hub to be processed. When the operator picks up and puts down the lock pin synchronizer hub through the gripping component 1, the external clamping device abuts against the outer side wall of each gripping component 1. During this process, the two support components 2 on the left and right sides of the compensation fixture abut against the inner wall of the outer spline 01 of the lock pin synchronizer hub to prevent the compensation fixture from falling off.

[0042] 2) After all materials are prepared, they are put into the heat treatment equipment for heat treatment, and kept flat throughout the heat treatment process;

[0043] 3. After heat treatment, when unloading, first remove all compensation units, and then transfer the locking pin synchronizer gear hub to the next process. After heat treatment using the split compensation fixture, the thermal distortion at groove 04 of the locking pin synchronizer gear hub is reduced by 0.01-1mm compared to the unused deformation, which effectively improves the spline accuracy of the locking pin synchronizer gear hub.

Claims

1. A split-type compensation fixture for controlling heat treatment distortion of the locking pin type synchronizer hub, characterized in that: It includes N compensation units corresponding to N grooves (04) of the synchronizer hub to be heat-treated, where N ≥ 3; each compensation unit includes a gripping component (1), two support components (2) and a compensation component (3); The lower end of the gripping component (1) is fixedly connected to the upper end of the compensation component (3). During gripping, the external clamps abut against the outer side walls of the N gripping components (1). The compensation component (3) is a cuboid structure, and its dimensions are adapted to the groove (04) of the locking pin synchronizer hub; Two support components (2) are symmetrically connected to the two side walls of the compensation component (3) along the width direction, and the bottom of the support component (2) is in contact with the bottom of the groove of the locking pin synchronizer hub ring groove, which is used to support the compensation component (3) that extends into the groove (04). When gripping, the two support components (2) abut against the inner wall of the locking pin synchronizer hub outer spline (01).

2. The split-type compensation fixture for controlling the heat treatment distortion of the locking pin type synchronizer hub according to claim 1, characterized in that: The gripping component (1) is integrally formed with two support components (2) and a compensation component (3).

3. The split-type compensation fixture for controlling heat treatment distortion of the locking pin type synchronizer hub according to claim 2, characterized in that: The grasping component (1) has a cuboid structure.

4. The split-type compensation fixture for controlling heat treatment distortion of the locking pin type synchronizer hub according to claim 3, characterized in that: The support component (2) has a cuboid structure.

5. The split-type compensation fixture for controlling heat treatment distortion of the locking pin type synchronizer hub according to claim 4, characterized in that: The width d of the compensation unit is 0.1-1.5 mm smaller than the width D of the locking pin type synchronizer hub groove (04), and the length w is 0.2-2 mm larger than the length W of the locking pin type synchronizer hub groove (04).

6. The split-type compensation fixture for controlling heat treatment distortion of the locking pin type synchronizer hub according to claim 5, characterized in that: The height h of the compensation component (3) is 0.1-1.5 mm higher than the height H of the external spline (01) of the locking pin synchronizer hub.

7. The split-type compensation fixture for controlling heat treatment distortion of the locking pin type synchronizer hub according to claim 6, characterized in that: The width of the gripping component (1) is the same as the width of the compensation component (3), and the height s of the gripping component (1) is greater than 10mm.

8. The split-type compensation fixture for controlling heat treatment distortion of the locking pin type synchronizer hub according to claim 7, characterized in that: The length, width, and height of the support component (2) are all less than 10 mm.

9. The split-type compensation fixture for controlling the heat treatment distortion of the locking pin type synchronizer hub according to claim 8, characterized in that: The N=3.

10. The split-type compensation fixture for controlling heat treatment distortion of the locking pin type synchronizer hub according to claim 1, characterized in that: The compensation unit is made of carburized steel.

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