New energy motor and reducer gear shaft connecting structure
Through a three-bearing arrangement structure and optimized design, the fatigue wear and noise problems of motor bearings in new energy vehicles under high loads have been solved, achieving long bearing life and low-cost high-performance motor connection.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- EWEA-TECH CO LTD
- Filing Date
- 2025-07-08
- Publication Date
- 2026-07-07
AI Technical Summary
Existing motor bearings for new energy vehicles are prone to fatigue wear under high load and high speed operation, resulting in a shortened lifespan. In addition, the commonly used arrangement structure has problems such as large axial space and noise, making it difficult to meet the requirements of high performance and economy.
The three-bearing arrangement structure eliminates the front bearing of the motor, retains the rear bearing of the motor, and retains two bearings in the reducer. Through spline fit, optical axis centering, elastic retaining ring limit, oil seal and conductive ring design, axial force and radial force are reasonably distributed and the space arrangement is optimized.
It improves bearing life and motor stability, reduces energy loss, solves the problem of bearing fatigue wear under high load, and also reduces noise and installation costs.
Smart Images
Figure CN224473150U_ABST
Abstract
Description
Technical Field
[0001] This utility model belongs to the field of new energy vehicle technology, specifically relating to a gear shaft connection structure for a new energy motor and reducer. Background Technology
[0002] New energy vehicles are electric vehicles driven primarily by electricity, with the motor being one of the core components. To improve the overall performance of electric vehicles, the performance of each key component must be continuously improved. For motors, the requirements include higher operating voltage, smaller size, and greater torque. Therefore, the output bearings of motors are required to withstand axial and radial forces, have a compact spatial arrangement, long rated life, and high reliability. The same applies to bearings in various parts of the transmission; furthermore, the market currently places higher demands on the quality and lifespan of easily worn parts in the transmission. Overall, bearings are required to continuously improve their performance to meet the power demands of the entire vehicle. To improve bearing performance, in addition to improving the design technology of the bearing structure itself and the manufacturing process, the rational and scientific matching and spatial arrangement of bearings is also a crucial breakthrough for technological advancement in the current automotive industry.
[0003] The greater the torque of a motor, the greater the force it generates during operation, resulting in a significant increase in the radial and axial loads on the bearings at the motor's output end. Bearings subjected to prolonged high loads experience increased contact stress between their internal rolling elements and raceways, making them prone to fatigue wear. This can lead to damage such as pitting and spalling, shortening their service life.
[0004] To achieve long bearing life and adaptability to high-speed, high-torque shafts during operation, the industry previously relied on improving the design requirements of the bearing structure or its machining precision. However, as design requirements and machining precision increase, the manufacturing cost of bearings also rises. For clients, controlling procurement costs is crucial, and excessive cost increases are unacceptable. Recent research on bearing spatial arrangement has not only solved certain cost issues but also improved motor output stability and power while reducing energy loss through rational spatial arrangement. Therefore, the rational matching of bearings and the scientific arrangement of spatial structures represent a significant breakthrough for technological advancement in the current automotive industry.
[0005] The spatial arrangement of bearings refers to the design of the installation position, quantity, type, and combination of bearings at three locations: the motor output end, the gear shaft input end, and the gear shaft output end. For example, a single bearing arrangement is simple in structure, occupies little space, and is low in cost; however, its load-bearing capacity is limited, making it difficult to withstand large radial and axial loads. Under high loads or high-speed operation, the shaft is prone to vibration and displacement, affecting motor performance and lifespan. A back-to-back arrangement increases shaft rigidity, enabling it to withstand larger axial forces and overturning moments, making it suitable for applications requiring large axial loads and high rigidity; however, it occupies more axial space and requires extremely high installation precision.
[0006] The commonly used motor-reducer arrangement in the industry is as follows: the motor uses a front and rear double bearing arrangement, the reducer input shaft uses a double bearing arrangement, and the motor and reducer are connected by a housing stop and a shaft spline fit. This arrangement has the problem of large axial space due to the use of a four-bearing structure; at the same time, the insufficient centering accuracy of the stop and spline fit is prone to low-frequency noise problems.
[0007] In summary, in order to achieve the requirements of long service life, good mechanical performance, and good economy for all bearing components, it is very important to design a reasonable bearing matching method and a scientific gear shaft spatial arrangement structure, while improving the bearing structural design requirements and manufacturing precision. Summary of the Invention
[0008] This utility model provides a gear shaft connection structure for a new energy motor and reducer. The motor and reducer adopt a three-bearing arrangement structure, eliminating the front bearing of the motor and retaining the rear bearing of the motor, while the reducer retains a two-bearing arrangement.
[0009] The technical solution adopted in this utility model is: a gear shaft connection structure for a new energy motor and reducer, characterized in that it includes:
[0010] The motor output shaft and gear input shaft are connected by a spline fit and axially aligned by optical axis centering.
[0011] The rear bearing of the motor is arranged on one side at the right end of the motor output shaft and mates with the bearing seat of the right end cover of the motor.
[0012] The gear shaft input shaft adopts a dual bearing arrangement, including a first reducer bearing and a second reducer bearing, which are respectively installed on the left end cover and the right end cover of the reducer, and axial limiting is achieved by the shaft shoulder, the first shaft elastic retaining ring and the second shaft elastic retaining ring;
[0013] A conductive ring and an input shaft oil seal are located between the motor output shaft and the right end cover of the reducer to prevent electro-corrosion and oil leakage.
[0014] A bushing and a wave spring are arranged on the input shaft of the gear shaft for adjusting the axial float.
[0015] The gear shaft output shaft adopts a dual bearing arrangement, including a third reducer bearing and a fourth reducer bearing, which are respectively limited by the elastic retaining rings of the third shaft and the elastic retaining rings of the fourth shaft, and cooperate with the left and right end covers of the reducer; the gear shaft output shaft is connected to the sun gear shaft through a spline and fixed by bolts, a first spacer and a second spacer, so as to realize the control of axial and radial floating amount.
[0016] Furthermore, a gap is reserved between the conductive ring and the input shaft oil seal to avoid contact friction.
[0017] Furthermore, the wave spring is coaxially installed inside the bushing, with one end in contact with the gear shaft input shaft and the other end in contact with the motor output shaft.
[0018] Furthermore, the third and fourth reducer bearings of the gear shaft output shaft, as well as the first and second reducer bearings of the gear shaft input shaft, are all deep groove ball bearings.
[0019] Furthermore, the outer ring of the motor output shaft's rear bearing is interference-fitted with the bearing housing of the right end cover of the motor, and the inner ring is fixed by a shoulder and interference fit.
[0020] Furthermore, a gear is provided on the output shaft of the gear shaft, and the gear is interference-fitted onto the output shaft of the gear shaft and limited by the shaft shoulder.
[0021] The beneficial effects of this utility model are as follows: the motor and reducer in this utility model solve the connection problem by centering with splines and optical shafts; the three-dimensional oil seal and conductive ring set at the bearing of the reducer solve the problems of oil leakage and electro-corrosion; the gear shaft output shaft adopts bolt connection and spacer structure to realize the floating amount design problem, and can be used with planetary gear set. Attached Figure Description
[0022] Figure 1 A schematic diagram of the bearing space layout design;
[0023] Figure 2 Enlarged schematic diagram of the bearing space layout design structure;
[0024] In the diagram: 1-Gear shaft output shaft, 2-Third reducer bearing, 3-Elastic retaining ring for the third shaft, 4-Gear, 5-First spacer, 6-Fourth reducer bearing, 7-Elastic retaining ring for the fourth shaft, 8-Bolt, 9-Second spacer, 10-Sun gear shaft, 11-First reducer bearing, 12-Elastic retaining ring for the first shaft, 13-Gear shaft input shaft, 14-Second reducer bearing, 15-Elastic retaining ring for the second shaft, 16-Motor rear bearing, 17-Motor output shaft, 18-Conductive ring, 19-Shaft sleeve, 20-Wave spring, 21-External spline, 22-Internal spline, 23-Input shaft oil seal. Detailed Implementation
[0025] To more clearly illustrate the technical solution of this utility model, the accompanying drawings used in the description will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other embodiments can be obtained based on these drawings without creative effort. To facilitate understanding of this utility model, a more detailed description of this utility model will be provided below in conjunction with the accompanying drawings and specific embodiments.
[0026] This utility model relates to a gear shaft connection structure for a new energy motor and reducer. It includes the selection and arrangement of bearings at three locations: the motor output bearing, the gear shaft input bearing, and the gear shaft output bearing for electric vehicles. This assembly rationally distributes the axial and radial forces borne by the shaft through bearing selection, axial float design, and spatial position design. While ensuring that the bearings meet the speed requirements, it also rationally arranges the bearing assembly space, so that the bearings meet the performance requirements of mechanical requirements, space constraints, lifespan requirements, and reliability requirements.
[0027] like Figure 1 As shown, this utility model is a gear shaft connection structure for a new energy motor and reducer, including a gear shaft output shaft 1, a third reducer bearing 2, a fourth reducer bearing 6, a first reducer bearing 11, a second reducer bearing 14, a gear shaft input shaft 13, a motor rear bearing 16, a motor output shaft 17, a conductive ring 18, a bushing 19, a wave spring 20, and an input shaft oil seal 23. The motor output shaft 17 bears both radial and axial forces, so an improved design is made on the traditional two bearings. The reducer adopts a three-bearing arrangement structure, eliminating the front bearing of the motor and retaining the rear bearing. The reducer retains a double-bearing arrangement.
[0028] The inner ring of the rear bearing 16 of the motor is axially limited on the left side by the shoulder of the motor output shaft 17, and radially pressed with an interference fit. The outer ring radially mates with the bearing seat of the right end cover of the motor. The motor output shaft 17 and the gear shaft input shaft 13 are connected by a spline. The inner ring of the second reducer bearing 14 is axially limited on the left side by the shoulder of the gear shaft input shaft 13, and radially pressed with an interference fit. The outer ring radially mates with the right end cover of the reducer, and the right side of the axial direction contacts the second shaft with an elastic retaining ring 15. The inner ring of the first reducer bearing 11 is axially limited on the right side by the shoulder of the gear shaft input shaft 13, and radially pressed with an interference fit. The outer ring radially mates with the left end cover of the reducer, and the left side of the axial direction contacts the first shaft with an elastic retaining ring 12. The third reducer... The inner ring of the reducer bearing 2 is axially limited on the left side by the shoulder of the gear shaft output shaft 1, and radially pressed with an interference fit. The outer ring radially mates with the right end cover of the reducer, and the axial right side contacts the third shaft with an elastic retaining ring 3. The inner ring of the fourth reducer bearing 6 is axially limited on the right side by the shoulder of the gear shaft output shaft 1, and radially pressed with an interference fit. The outer ring radially mates with the left end cover of the reducer, and the axial left side contacts the fourth shaft with an elastic retaining ring 7. The sun gear shaft 10 and the gear shaft output shaft 1 are connected by a spline and locked with bolts 8. The axial floating amount is controlled by the first spacer 5 and the second spacer 9. The gear 4 is interference-fitted onto the gear shaft output shaft 1, and the inner ring of the gear 4 is axially limited on the right side by the shoulder of the gear shaft output shaft 1.
[0029] like Figure 2 As shown, bushing 19 is installed on gear shaft input shaft 13. The left side of bushing 19 contacts the second shaft with elastic retaining ring 15. Wave spring 20 is coaxially arranged with bushing 19 and placed inside bushing 19. The left side of wave spring 20 contacts gear shaft input shaft 13, and the right side of wave spring 20 contacts motor output shaft 17. It is used to absorb axial vibration and compensate for assembly tolerances. Conductive ring 18 is installed on motor output shaft 17. The external spline 21 of motor output shaft 17 is splined with the internal spline 22 of gear shaft input shaft 13, and the two shafts are aligned with the optical axis. Conductive ring 18 and input shaft oil seal 23 are installed between the right end cover of the gearbox and the motor output shaft to prevent electro-corrosion and oil leakage. There is a gap between the right side of input shaft oil seal 23 and conductive ring 18 to avoid contact friction.
[0030] The various embodiments described in this specification are presented in a progressive manner, with each embodiment focusing on its differences from other embodiments. Similar or identical parts between embodiments can be referred to interchangeably. The above description of the disclosed embodiments enables those skilled in the art to implement or use this invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of this invention. Therefore, this invention is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.
Claims
1. A gear shaft connection structure for a new energy motor and reducer, characterized in that, include: The motor output shaft (17) and the gear shaft input shaft (13) are connected by the spline (21) on the motor output shaft (17) and the internal spline (22) in the gear shaft input shaft (13); The rear bearing (16) of the motor is arranged on one side at the right end of the output shaft (17) of the motor and is matched with the bearing seat of the right end cover of the motor. The gear shaft input shaft (13) adopts a double bearing arrangement, including a first reducer bearing (11) and a second reducer bearing (14), which are respectively installed on the left end cover and the right end cover of the reducer, and axially limited by the shaft shoulder, the first shaft elastic retaining ring (12) and the second shaft elastic retaining ring (15); The conductive ring (18) and the input shaft oil seal (23) are located between the motor output shaft (17) and the right end cover of the reducer to prevent electro-corrosion and oil leakage; A bushing (19) and a wave spring (20) are arranged on the gear shaft input shaft (13) for adjusting the axial float. The gear shaft output shaft (1) adopts a double bearing arrangement, including a third reducer bearing (2) and a fourth reducer bearing (6), which are respectively limited by the third shaft elastic retaining ring (3) and the fourth shaft elastic retaining ring (7), and cooperate with the left and right end covers of the reducer; the gear shaft output shaft (1) is connected to the sun gear shaft (10) by spline, and is fixed by bolts (8), the first spacer (5) and the second spacer (9) to realize axial and radial floating amount control.
2. The gear shaft connection structure for a new energy motor and reducer according to claim 1, characterized in that, A gap is reserved between the conductive ring (18) and the input shaft oil seal (23) to avoid contact friction.
3. The gear shaft connection structure for a new energy motor and reducer according to claim 1, characterized in that, The wave spring (20) is coaxially installed inside the bushing (19), with one end in contact with the gear shaft input shaft (13) and the other end in contact with the motor output shaft (17).
4. The gear shaft connection structure for a new energy motor and reducer according to claim 1, characterized in that, The third reducer bearing (2) and the fourth reducer bearing (6) of the output shaft (1) of the gear shaft, as well as the first reducer bearing (11) and the second reducer bearing (14) of the input shaft (13) of the gear shaft, are all deep groove ball bearings.
5. The gear shaft connection structure for a new energy motor and reducer according to claim 1, characterized in that, The outer ring of the motor output shaft (17) rear bearing (16) is interference-fitted with the bearing seat of the right end cover of the motor, and the inner ring is fixed by the shaft shoulder and interference fit.
6. The gear shaft connection structure for a new energy motor and reducer according to claim 1, characterized in that, The gear (4) is provided on the output shaft (1) of the gear shaft. The gear (4) is press-fitted onto the output shaft (1) of the gear shaft and is limited by the shaft shoulder.