Speed reducer input shaft with high-precision internal spline structure for electric drive axle

Abstract

The speed reducer input shaft with the high-precision internal spline structure for the electric drive axle comprises an input shaft body, an axial through hole is formed in the center of the input shaft body, an internal spline is arranged in the through hole, and the diameter of the through hole is larger than that of the addendum circle of the internal spline. The rubber plug is assembled in the through hole and is used for sealing the through hole to prevent the lubricating oil from leaking; and the elastic check ring for the hole is fixed at the end part of the through hole and is used for axially limiting the rubber plug. By changing the structure of the input shaft of the speed reducer, the internal spline can be subjected to broaching finish machining after heat treatment, so that the precision of the internal spline is ensured, and the NVH (Noise Vibration and Harshness) performance when the speed reducer and a motor are connected for operation is improved.

Description

Technical Field

[0001] This utility model belongs to the field of speed reducer technology, and in particular relates to an input shaft for an electric drive bridge speed reducer with a high-precision internal spline structure. Background Technology

[0002] In the electric drive system of new energy vehicles, the spline on the input shaft of the electric drive axle reducer is a key transmission component connecting the motor output shaft and the reducer. Its structural design and machining quality directly determine the stability and reliability of power transmission. Currently, the splines on the input shaft of the electric drive axle reducer are mainly divided into two structural forms: external splines and internal splines. Among them, internal splines are widely used in compact electric drive systems due to their advantages such as precise axial positioning and compact assembly space. The choice of machining process for internal splines has a profound impact on their performance. The industry mainly uses gear shaping technology to form the tooth profile of internal splines. This process has the characteristics of high machining efficiency and stable tooth profile accuracy, which can meet the needs of mass production.

[0003] However, the internal splines after forming require heat treatment to increase surface hardness, a process that inevitably leads to deformation. During heat treatment, thermal stress is generated within the material due to temperature gradients, causing distortion of the spline shape. Especially for internal spline structures with uneven wall thickness, the stress concentration caused by differences in cooling rates in thin-walled areas further amplifies the deformation effect.

[0004] This precision defect directly affects the matching performance of the transmission system: when the internal spline of the reducer input shaft mates with the external spline of the motor output shaft, the tooth surface contact area becomes skewed due to deformation, resulting in uneven contact stress distribution. When the reducer operates at high speed, this non-uniform contact will excite high-frequency vibration, causing abnormal noise and other NVH problems, seriously affecting driving comfort. Summary of the Invention

[0005] The purpose of this invention is to provide an input shaft for an electric drive bridge reducer with a high-precision internal spline structure, which solves the NVH problem caused by the low precision of the internal spline in the reducer.

[0006] The technical solution adopted in this utility model is as follows: an input shaft for an electric drive bridge reducer with a high-precision internal spline structure, including an input shaft body, an axial through hole at the center of the input shaft body, an internal spline in the through hole, the diameter of the through hole being larger than the tip circle diameter of the internal spline; a rubber plug, assembled in the through hole, for sealing the through hole to prevent lubricating oil leakage; and an elastic retaining ring for the hole, fixed to the end of the through hole, for axially limiting the rubber plug.

[0007] Furthermore, the outer diameter of the rubber plug is interference-fitted with the inner diameter of the through hole.

[0008] Furthermore, the elastic retaining ring for the hole is an annular open elastic element, the outer diameter of which matches the groove at the end of the through hole.

[0009] The beneficial effects of this utility model are as follows: By changing the structure of the input shaft of the reducer, the internal spline can be broached and precision machined after heat treatment, which ensures the accuracy of the internal spline and improves the NVH performance when the reducer is connected to the motor. Attached Figure Description

[0010] Figure 1 This is a schematic diagram of the structure of this utility model;

[0011] In the diagram: 1-Elastic retaining ring for the hole, 2-Rubber plug, 3-Input shaft body, 4-Internal spline, 5-Through hole, 6-Slot. Detailed Implementation

[0012] The present invention will be further described below with reference to the accompanying drawings.

[0013] like Figure 1 As shown, this utility model relates to an input shaft for an electric drive bridge reducer using a high-precision internal spline structure. It includes an input shaft body 3, a rubber plug 2, and a retaining ring 1 for the bore. The input shaft body 1 has an axial through-hole 5 at its center, within which an internal spline 4 is located. The diameter of the through-hole 5 is larger than the addendum circle diameter of the internal spline, allowing the internal spline 4 to be broached after heat treatment. The rubber plug 2 is fitted into the through-hole 5, with its outer diameter interfering with the inner diameter of the through-hole 5, sealing the through-hole 5 to prevent lubricant leakage during reducer operation. The retaining ring 1 is fixed to the end of the through-hole 5. The retaining ring 1 is an annular open elastic element, its outer diameter matching the groove 6 at the end of the through-hole 5, axially limiting the rubber plug 2 and preventing it from dislodging during high-speed operation of the input shaft.

[0014] The present invention, through the above structure, facilitates the implementation of the broaching process after heat treatment of the internal spline of the input shaft, improves the accuracy of the internal spline of the input shaft, and ensures the sealing performance of the input shaft.

Claims

1. An electric drive axle reducer input shaft with high-precision internal spline structure, characterized in that, include: The input shaft body (3) has an axial through hole (5) at its center, and an internal spline (4) is provided in the through hole (5). The diameter of the through hole is larger than the tooth tip circle diameter of the internal spline (4). A rubber plug (2) is fitted into the through hole (5) to seal the through hole (5) and prevent lubricating oil leakage; An elastic retaining ring (1) is fixed to the end of the through hole (5) to axially limit the rubber plug (2).

2. The reducer input shaft with high-precision internal spline structure for electric drive axle according to claim 1, characterized in that: The outer diameter of the rubber plug (2) is interference-fitted with the inner diameter of the through hole (5).

3. The input shaft of a reducer for an electric drive bridge with a high-precision internal spline structure according to claim 1, characterized in that: The elastic retaining ring (1) for the hole is an annular open elastic element, and its outer diameter matches the groove (6) at the end of the through hole (5).

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