CN216715166U

CN216715166U - Novel new energy automobile reduction gear and reduction gear input shaft

Info

Publication number: CN216715166U
Application number: CN202123185928.6U
Authority: CN
Inventors: 孟庆振; 李渠成; 吴允锋; 张成林; 袁勃
Original assignee: Anhui Xingrui Gear Transmission Co ltd
Current assignee: Anhui Xingrui Gear Transmission Co ltd
Priority date: 2021-12-17
Filing date: 2021-12-17
Publication date: 2022-06-10
Anticipated expiration: 2031-12-17

Abstract

The utility model discloses a novel new energy automobile speed reducer and a speed reducer input shaft, wherein the input shaft is a gear shaft with a hollow structure, a stepped hole is formed in the middle of the input shaft, an internal spline is arranged on the stepped hole, and a shaft sleeve is further arranged on the inner side of the internal spline; a speed reducer comprising the input shaft of claim 1, further comprising a left housing, a right housing, a pinion shaft assembly, and a differential assembly; the input shaft is provided with a first transmission gear, the intermediate gear shaft assembly comprises an intermediate gear shaft and an intermediate shaft driven gear, a second transmission gear is arranged on the intermediate gear shaft, and the differential assembly is provided with a main reduction gear and a half shaft spline. The input shaft is additionally provided with a shaft sleeve design, so that the 1 st order and harmonic order performance of the input shaft caused by motor shaft fluctuation can be obviously improved; the first transmission gear, the second transmission gear, the intermediate shaft driven gear and the main reduction gear are designed to have small modulus, small pressure angle, large helical angle and large tooth width, so that the contact ratio is improved, the noise is reduced, the strength is increased, and the large-torque transmission is realized.

Description

Novel new energy automobile reduction gear and reduction gear input shaft

Technical Field

The utility model relates to the field of reducer design, in particular to a novel new energy automobile reducer and a reducer input shaft.

Background

With the international increasing importance on the earth environment, the automobile exhaust emission becomes the first improvement point, the development of new energy automobiles becomes more and more important, and the nation has determined to develop new energy automobiles vigorously on the strategy, so that the new energy automobiles not only realize zero emission, but also must give consideration to the comfort and the safety of transmission automobiles.

At present, electric reducers on the market are various in variety, and particularly, a large-torque electric reducer with a two-stage transmission structure generally has the defects of large integral volume, poor impact resistance, small transmitted power and the like. Therefore, a large-torque pure electric speed reducer needs to be designed, the structure is compact, the torque-to-mass ratio is high, the reliability is high, and the drivability, the dynamic performance, the economy and the safety of a pure electric vehicle are greatly improved.

In addition, a new energy pure electric vehicle power assembly generally comprises a motor and a speed reducer, and the motor and the speed reducer are independently designed and assembled and then fixedly connected together through bolts. The new energy automobile adopts the motor to replace the engine, so that the motor has low noise. However, the motor shaft is not supported at the end of the speed reducer, and is similar to a cantilever beam structure, so that the vibration is easy to generate, and the noise of the motor and the noise of the speed reducer assembly seriously affects the NVH performance of the whole vehicle.

Disclosure of Invention

In order to overcome the defects of the prior art, the utility model aims to provide a novel new energy automobile speed reducer and a speed reducer input shaft so as to realize large-torque transmission and solve the NVH problem caused by the reasons.

Therefore, the utility model provides a novel input shaft of a new energy automobile speed reducer, wherein the input shaft is a gear shaft with a hollow structure, a stepped hole is formed in the middle of the input shaft, an internal spline is arranged on the stepped hole, and a shaft sleeve is further arranged on the inner side of the internal spline; the inner spline is matched with the outer spline on the motor shaft, the inner diameter of the shaft sleeve is smaller than the small diameter of the inner spline, and the shaft sleeve is in clearance fit with the guide column at the front end of the motor shaft, so that the 1-order and harmonic-order performances generated by motor shaft fluctuation are improved, and the NVH performance of the power assembly is improved.

Further, the shaft sleeve is an HT200 gray iron casting with the effects of shock absorption and self-lubrication.

The utility model also provides a novel new energy automobile speed reducer which comprises the input shaft, a left shell, a right shell, an intermediate gear shaft assembly and a differential assembly, wherein the left shell is arranged on the left shell; the input shaft is provided with a first transmission gear, the intermediate gear shaft assembly comprises an intermediate gear shaft and an intermediate shaft driven gear, a second transmission gear is arranged on the intermediate gear shaft, and the differential mechanism assembly is provided with a main reduction gear and a half shaft spline.

The intermediate shaft driven gear is meshed with the first transmission gear, the main reduction gear is meshed with the second transmission gear, and the differential assembly is connected with a transmission shaft through the half shaft spline to realize speed reduction transmission; the transmission gear I, the transmission gear II, the intermediate shaft driven gear and the main reduction gear are designed by adopting a small modulus, a small pressure angle, a large helical angle and a large tooth width, so that the contact ratio is improved, the strength is increased, and the large-torque transmission is realized.

Furthermore, the modulus of the first transmission gear and the driven gear of the intermediate shaft is in the range of 1.4-2.0, the pressure angle is in the range of 16-20 degrees, and the helical angle is in the range of 25-31 degrees.

Furthermore, the modulus of the second transmission gear and the main reduction gear is within the range of 1.9-3.0, the pressure angle is within the range of 17-22.5 degrees, the helical angle is within the range of 18-25 degrees, and the tooth width is within the range of 30-60 mm.

Furthermore, an oil seal I is arranged in a space formed by the right side of the input shaft and the right shell, the oil seal I is a bidirectional oil return line oil seal, and a blank cap is arranged inside one end of the left side of the input shaft.

Furthermore, the input shaft adopts a hollow design, and the intermediate gear shaft also adopts a hollow design, so that the weight reduction is facilitated.

Furthermore, the left end of the intermediate gear shaft is connected with the left shell through a second deep groove ball bearing, the right end of the intermediate gear shaft is connected with the right shell through a third deep groove ball bearing, and a second adjusting gasket is arranged at a gap between the second deep groove ball bearing and the left shell.

Furthermore, an oil seal II is arranged in a space formed by the differential assembly and the left shell, and the oil seal II is a bidirectional oil return line oil seal.

Furthermore, the differential assembly is respectively connected with the left shell and the right shell through a pair of tapered roller bearings, and a third adjusting gasket is arranged between the tapered roller bearings and the left shell.

According to the novel new energy automobile speed reducer and the speed reducer input shaft, the shaft sleeve design is added on the input shaft, so that the 1-order and harmonic-order performances of the input shaft due to motor shaft fluctuation can be obviously improved; and judging whether the 1 st order and the harmonic order thereof are generated by the motor shaft according to the scheme; the NVH problem caused by motor shaft fluctuation can be obviously reduced, and the NVH performance of the power assembly is improved; the input shaft structure meets the design requirements of the existing mainstream pure electric automobile, and has excellent performance.

In the preferred scheme of the utility model, the input shaft, the intermediate gear shaft assembly and the differential assembly are arranged to realize speed reduction rotation; the transmission gear I, the transmission gear II, the intermediate shaft driven gear and the main reduction gear adopt a small modulus, a small pressure angle, a large helical angle and a large tooth width design, so that the contact ratio is improved, the noise is reduced, the strength is increased, and the large-torque transmission is realized; by arranging the first adjusting gasket, the second adjusting gasket and the third adjusting gasket, the gap between the shell and the bearing can be eliminated, and the service life of the bearing is prolonged; through setting up oil blanket one, oil blanket two and stifle, can play sealed, prevent the effect of reduction gear oil leak.

In addition to the objects, features and advantages described above, other objects, features and advantages of the present invention are also provided. The present invention will be described in further detail below with reference to the drawings.

Drawings

The accompanying drawings, which are incorporated in and constitute a part of this application, illustrate embodiments of the utility model and, together with the description, serve to explain the utility model and not to limit the utility model. In the drawings:

FIG. 1 is a schematic structural diagram of a novel new energy automobile speed reducer of the utility model;

FIG. 2 is a schematic structural diagram of an input shaft in the novel new energy automobile speed reducer;

FIG. 3 is a schematic structural diagram of a shaft sleeve in the novel new energy automobile speed reducer of the utility model;

fig. 4 is a schematic view of a motor shaft mated with the input shaft.

Description of the reference numerals

1. A left housing; 2. adjusting a first gasket; 3. a first deep groove ball bearing; 4. an input shaft; 41. a first transmission gear; 42. an internal spline; 5. covering the blank with a cover; 6. adjusting a second gasket; 7. a second deep groove ball bearing; 8. an intermediate gear shaft assembly; 81. a countershaft driven gear; 82. a second transmission gear; 9. a differential assembly; 91. a main reduction gear; 10. a tapered roller bearing; 11. Oil seal II; 12. adjusting a third gasket; 13. hexagonal flange face bolts; 14. a right housing; 15. a deep groove ball bearing III; 16. a shaft sleeve; 17. oil seal one; 18. a motor shaft; 181. an external spline; 182. and a guide post.

Detailed Description

It should be noted that, in the present application, the embodiments and features of the embodiments may be combined with each other without conflict. The present invention will be described in detail below with reference to the embodiments with reference to the attached drawings.

As shown in fig. 1 to 4, the novel new energy automobile speed reducer of the utility model comprises a left shell 1, a right shell 14, an input shaft 4, an intermediate gear shaft assembly 8 and a differential assembly 9; the inside of the input shaft 4 is connected with an external spline of the output end of the motor through a spline, a first transmission gear is arranged on the input shaft 4, a first transmission gear 41 is meshed with a middle shaft driven gear 81 on a middle gear shaft assembly 8, the middle shaft driven gear 81 on the middle gear shaft assembly 8 is meshed with a main reduction gear on a differential mechanism assembly 9, the differential mechanism assembly 9 is connected with the transmission shaft through a half shaft spline, and the transmission shaft is connected with wheels to provide rotating speed.

Specifically, two ends of the input shaft 4 are respectively fixed on the left shell 1 and the right shell 14 through the deep groove ball bearings 3, an adjusting gasket 2 is arranged at an interval between the deep groove ball bearing 3 at one end of the left side of the input shaft 4 and the left shell 1, and the adjusting gasket 2 is used for eliminating a gap between the deep groove ball bearing 3 and the left shell, so that the service life of the bearing is prolonged.

The input shaft 4 is a gear shaft, a hollow design is adopted, a stepped hole is formed in the input shaft, a first transmission gear 41 is arranged on the outer circumferential surface of the input shaft, an inner spline 42 is arranged in one end of the right side of the input shaft 4, and the inner spline is connected with an outer spline 181 of the motor shaft 18 to play a role in power input.

As shown in fig. 1, an oil seal 17 is disposed in a space formed by the outer side of the right end of the input shaft 4 and the right housing 14, and the oil seal 17 is a two-way oil return line oil seal, which can play a role of sealing and prevent the lubricating oil from flowing out from the end of the input shaft 4. The inner part of one end of the left side of the input shaft 4 is provided with a blank cap 5, the blank cap 5 has the same function as the first oil seal 17, and plays a role in sealing to prevent lubricating oil from flowing out from the hollow part of the input shaft 4.

Specifically, the intermediate gear shaft assembly includes an intermediate gear shaft and an intermediate shaft driven gear 81, the intermediate gear shaft is hollow and is beneficial to weight reduction, the intermediate gear shaft and the intermediate shaft driven gear 81 are connected in a spline mode, and the intermediate shaft driven gear 81 is in gear engagement with a first transmission gear 41 arranged on the input shaft 4. And a second transmission gear 82 is arranged on the outer circumferential surface of the intermediate gear shaft, the addendum circle of the second transmission gear 82 is smaller than that of the intermediate shaft driven gear 81, and the number of teeth of the second transmission gear 82 is smaller than that of the intermediate shaft driven gear 81.

As shown in fig. 1, the left end of the intermediate gear shaft is connected with the left shell 1 through the second deep groove ball bearing 7, the right end of the intermediate gear shaft is connected with the right shell 14 through the third deep groove ball bearing 15, and an adjusting gasket II 6 is arranged at a gap between the second deep groove ball bearing 7 and the left shell 1 and used for eliminating a gap between the intermediate gear shaft assembly 8 and the left shell 1, so that the service life of the bearing is prolonged.

Specifically, as shown in fig. 1, a main reducing gear 91 is provided in the differential assembly 9, the main reducing gear 91 is engaged with the second transmission gear 82 on the intermediate gear shaft to transmit torque, a half-shaft spline is further provided on the differential assembly 9, and the differential assembly 9 is connected with the transmission shaft through the half-shaft spline, so that power can be transmitted to the wheels.

An oil seal II 11 is arranged in a space formed by the differential assembly 9 and the left shell 1, and the oil seal II is a two-way oil return line oil seal and can play a role in preventing oil leakage of the speed reducer. The two ends of the differential assembly 9 are respectively connected with the left shell 1 and the right shell 14 through a pair of tapered roller bearings 10, and a third adjusting gasket 12 is arranged between the tapered roller bearings 10 and the left shell 1 and used for eliminating a gap between the differential assembly 9 and the left shell, so that the service life of the bearings is prolonged.

When in specific use, the motion principle of the speed reducer is as follows: motor → spline on input shaft 4 → first transmission tooth 41 on input shaft 4 → driven gear 81 on intermediate shaft on intermediate gear shaft assembly 8 → second transmission tooth 82 on intermediate gear shaft assembly 8 → main reducing gear 91 on differential assembly 9 → internal spline of gear on intermediate shaft on differential assembly 9 → transmission shaft → wheel.

In the reducer assembly of the utility model, the left shell 1 and the right shell 14 are connected through a plurality of hexagonal flange face bolts 13, and the left shell 1 and the right shell 14 have wrapping and supporting functions and are used for fixing and supporting a bearing, thereby being beneficial to the rotation, namely lubrication, of the bearing.

In the embodiment, the first transmission gear 41 on the input shaft 4, the second transmission gear 82 and the driven gear 81 in the intermediate gear shaft assembly, and the main reduction gear 91 in the differential assembly 9 all adopt a small modulus, a small pressure angle, a large helix angle and a large tooth width, which are beneficial to improving contact ratio, reducing noise, increasing strength and realizing large-torque transmission.

The modulus of the transmission gear I41 and the intermediate shaft driven gear 81 is within the range of 1.4-2.0, the pressure angle is within the range of 16-20 degrees, the large helical angle is within the range of 25-31 degrees, the modulus of the transmission gear II 82 and the main reducing gear 91 is within the range of 1.9-3.0, the pressure angle is within the range of 17-22.5 degrees, the large helical angle is within the range of 18-25 degrees, and the tooth width is within the range of 30-60 mm.

As shown in fig. 2 to 4, in order to improve the 1 st order and harmonic order performance caused by the motor shaft fluctuation, a sleeve 16 is provided inside the inner spline; the inner diameter of the shaft sleeve 16 is smaller than the small diameter of the internal spline, and the shaft sleeve 16 is in clearance fit with the guide post 182 at the front end of the motor shaft 18 to provide auxiliary support for the motor shaft, so as to improve the performance of 1 order and harmonic order generated by the fluctuation of the motor shaft 18 and improve the NVH performance of the power assembly.

In actual product design, the outer diameter of the sleeve 16 is set to be

The inner diameter of the sleeve 16 is set to

The size of the stepped hole on the input shaft matched with the shaft sleeve is

The outer diameter of the guide post 182 at the front end of the motor shaft is set to be

The shaft sleeve 16 is in interference fit with the input shaft 4, the shaft sleeve and the motor shaft form clearance fit, and design requirements are met, wherein the input shaft 4 and the motor shaft 18 are made of 20CrMnTiH materials; the shaft sleeve 16 is made of HT200 materials, has the shock absorption and self-lubricating effects and is low in cost.

In order to verify that the 1 st order and harmonic order performance generated by the fluctuation of the motor shaft 18 can be improved by adding a shaft sleeve between the input shaft and the motor shaft, and the NVH performance of the power assembly is improved. The designer sets two groups of comparison tests, the input shaft of the speed reducer and the motor shaft in the first group of tests are assembled conventionally, and the input shaft does not contain a shaft sleeve; in the second set of tests, a bushing was added between the input shaft of the reducer and the motor shaft, and the motor shaft was machined to the shape shown in fig. 4.

In two sets of experiments, the parameters of the reducer assembly are shown in table 1:

table 1 (reducer assembly partial parameter table)

And parts of the two groups of test reducer assemblies are all processed by hot post-grinding, and the precision is consistent. The matching part of the input shaft of the speed reducer and the bush is processed after being heated, so that the deformation caused by heat treatment is prevented, and the matching size of the input shaft and the bush is not influenced; the shaft sleeve is made of gray iron, has the shock absorption and self-lubricating effects and is low in cost.

The test vehicle is the same, and only the reducer assembly is replaced during testing, and the speed reducer assembly is unchanged. And analyzing by adopting Simcenter Test lab software, testing a low-gear sliding state, arranging vibration sensors at the ends of the motor and the reducer respectively, and intercepting vibration and comparing with a colormap of noise in the vehicle.

The test results obtained after several tests are as follows:

1) compared with a vibration colormap, the 1 st order and the harmonic order thereof in the state without the shaft sleeve are obvious in noise in the vehicle, near field noise and shell vibration; 1 order and harmonic order thereof are obviously reduced under the condition of containing the shaft sleeve;

2) compared with a noise colormap, the sliding squeal disappears under the condition of containing the shaft sleeve, and the order performance of the input shaft is obviously superior to that under the condition of not containing the shaft sleeve;

3) the tester subjectively evaluates the whole vehicle, the complete vehicle squeaking is obvious without the shaft sleeve state, and the judgment is not acceptable; the squeal is not obvious under the condition of containing the shaft sleeve and is acceptable.

In conclusion, the inner shaft sleeve is added on the input shaft of the speed reducer, so that the problem of squeal of a power assembly caused by motor shaft fluctuation can be solved; the sliding problem caused by the spline matching problem of the motor and the speed reducer is solved; the power assembly NVH is improved obviously, and 1 st order and harmonic orders thereof are proved to be mainly generated by a motor shaft.

It should be noted that, in order to reduce the radial run-out of the motor shaft when the motor shaft is matched with the input shaft, different structures may also be adopted, for example, the shaft sleeve structure is directly integrated on the input shaft, that is, an annular boss is arranged inside the internal spline of the input shaft, and the annular boss is matched with the guide post at the front end of the motor shaft, so as to improve the 1 st order and harmonic order performance generated by the fluctuation of the motor shaft 18, and improve the NVH performance of the power assembly.

The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention, and various modifications and changes may be made by those skilled in the art. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. The novel input shaft of the new energy automobile speed reducer is characterized in that the input shaft (4) is a gear shaft with a hollow structure, a stepped hole is formed in the middle of the input shaft (4), an internal spline (42) is arranged on the stepped hole, and a shaft sleeve (16) is further arranged on the inner side of the internal spline;

the inner spline (42) is matched with an outer spline (181) on a motor shaft (18), the inner diameter of the shaft sleeve (16) is smaller than the small diameter of the inner spline, and the shaft sleeve (16) is in clearance fit with a guide post (182) at the front end of the motor shaft (18), so that the 1 st order and harmonic order performance caused by motor shaft fluctuation is improved, and the NVH performance of a power assembly is improved.

2. The input shaft of the new-energy automobile speed reducer is characterized in that the shaft sleeve (16) is made of HT200 gray iron casting with the effects of shock absorption and self lubrication.

3. A novel new energy automobile speed reducer is characterized by comprising the input shaft (4) of claim 1, a left shell (1), a right shell (14), an intermediate gear shaft assembly (8) and a differential assembly (9);

the input shaft (4) is provided with a first transmission gear (41), the intermediate gear shaft assembly (8) comprises an intermediate gear shaft and an intermediate shaft driven gear (81), a second transmission gear (82) is arranged on the intermediate gear shaft, and the differential assembly (9) is provided with a main reduction gear (91) and a half shaft spline;

the intermediate shaft driven gear (81) is in gear engagement with the first transmission gear (41), the main reduction gear (91) is in gear engagement with the second transmission gear (82), and the differential assembly (9) is connected with a transmission shaft through the half shaft spline to realize speed reduction transmission;

the first transmission gear (41), the second transmission gear (82), the intermediate shaft driven gear (81) and the main reduction gear (91) are designed to have a small modulus, a small pressure angle, a large spiral angle and a large tooth width, so that the contact ratio is improved, the bending strength and the contact strength are increased, and the large-torque transmission is realized.

4. The novel speed reducer of new energy vehicles according to claim 3, characterized in that the modulus of the first driving gear (41) and the counter driven gear (81) is in the range of 1.4-2.0, the pressure angle is in the range of 16-20 °, and the helix angle is in the range of 25-31 °.

5. The novel new energy automobile speed reducer according to claim 4, wherein the modulus of the second transmission gear (82) and the main reduction gear (91) is within a range of 1.9-3.0, the pressure angle is within a range of 17-22.5 degrees, the helix angle is within a range of 18-25 degrees, and the tooth width is within a range of 30-60 mm.

6. The novel new energy automobile speed reducer according to claim 3, wherein a first oil seal (17) is arranged in a space formed by the right side of the input shaft (4) and the right shell (14), the first oil seal (17) is a bidirectional oil return line oil seal, and a blank cover (5) is arranged inside one end of the left side of the input shaft (4).

7. The novel new energy automobile speed reducer according to claim 3, characterized in that the input shaft (4) is of a hollow design, and the intermediate gear shaft is also of a hollow design, so that weight reduction is facilitated.

8. The novel new energy automobile speed reducer according to claim 3, wherein the left end of the intermediate gear shaft is connected with the left shell (1) through a second deep groove ball bearing (7), the right end of the intermediate gear shaft is connected with the right shell (14) through a third deep groove ball bearing (15), and a second adjusting gasket (6) is arranged in a gap between the second deep groove ball bearing (7) and the left shell (1).

9. The novel new energy automobile speed reducer according to claim 3, wherein a second oil seal (11) is arranged in a space formed by the differential assembly (9) and the left shell (1), and the second oil seal (11) is a bidirectional oil return line oil seal.

10. The new-energy automobile speed reducer according to claim 3, wherein the differential assembly (9) is connected with the left housing (1) and the right housing (14) through a pair of tapered roller bearings (10), and a third adjusting washer (12) is arranged between the tapered roller bearings (10) and the left housing (1).