WO2019178848A1

WO2019178848A1 - Linear shaft for differential and differential

Info

Publication number: WO2019178848A1
Application number: PCT/CN2018/080253
Authority: WO
Inventors: 余磊; 郁开宇; 陈苏涛
Original assignee: 舍弗勒技术股份两合公司
Priority date: 2018-03-23
Filing date: 2018-03-23
Publication date: 2019-09-26
Also published as: CN111684180A

Abstract

Disclosed is a linear shaft (5) for a differential (1). The linear shaft (5) is used for connecting two planetary gears (3) of the differential (1); the linear shaft (5) is of a cylindrical shape; and the linear shaft (5) in an axial direction is divided into an intermediate section (8) in the middle, connecting sections (9) located on two sides of the intermediate section (8) and used for connecting to the planetary gears (3), respectively, and end sections (10) located on two respective end sides and abutting the connecting sections (9). A radially extending through hole (11) is provided on one end section (10) of the linear shaft (5), and the linear shaft (5) is fixedly connected to a housing (2) of the differential (1) by a fastener (13) passing through the through hole (11). One or more throughout holes (12) are provided on the intermediate section (8) of the linear shaft (5).

Description

One-axis and differential for the differential

Technical field

The present invention relates to a slot for a differential and a corresponding differential for connecting two planet gears of a differential, wherein the slot has a cylindrical shape along The axial direction can divide the inline shaft into an intermediate section in the middle, a connecting section on the two sides of the intermediate section for the respective connection with the planet gears, and an end adjacent to the connecting section on the two end sides, respectively. And a segment, wherein a radially extending through hole is provided in one of the end portions of the inline shaft, the inline shaft being fixedly coupled to the housing of the differential by a fastener passing through the through hole.

Background technique

As electric vehicles become more and more popular, the NVH problem of the gearbox becomes more and more prominent due to the quietness of the motor. There is an increasing need to improve the NVH of the gearbox to achieve a quieter transmission system.

A differential for vehicles, including planetary gears and side gears, is known from CN 204692497 U. In order to simplify the structure, a cylindrical one-axis is used in the differential to connect the two planetary gears instead of the prior art in which the four planetary gears are fixed by a cross shaft.

A drive axle assembly using an integral differential housing is also known from CN 206092869 U, in which a word shaft is also provided for connecting and fixing the planetary gears. a pin through hole is laterally disposed at one end of the slot, and a pin hole is transversely penetrated through the integral differential case corresponding to the pin through hole, and the slot is passed through the pin through the slotted pin The via and pin holes are connected to the integral differential case.

The use of a word axis in the differential, although reducing the number of components, does not improve the NVH of the differential. According to the calculation, the vibration energy of the word axis can reach 21.6%. Therefore, if the vibration of the one-axis shaft during the operation of the differential can be reduced, the NVH of the differential can be well improved.

Summary of the invention

Therefore, the technical problem to be solved by the present invention is to improve the one-axis of the differential and reduce its vibration during the operation of the differential to improve the NVH of the entire system.

The technical problem is solved by a spindle for a differential shaft for connecting two planet gears of a differential, wherein the slotted shaft has a cylindrical shape along an axis Dividing the word axis into an intermediate portion in the middle, a connecting portion on each side of the intermediate portion for connecting to the planetary gears, and a connection to the two end sides respectively An end segment adjacent to the segment, wherein a radially extending through hole is provided in one of the end portions of the inline shaft, the inline shaft passing through the fastener passing through the through hole and the The housing of the differential is fixedly connected. According to the technical solution of the present invention, one or more through holes are provided on the intermediate portion of the word axis, that is, one or more of the number of through holes may be provided. Due to the opening in the word axis, the vibration of the word axis during the operation of the differential can be reduced, thereby reducing the proportion of vibration energy in the entire system. According to the experimental measurement, since the through hole can reduce the vibration of the word shaft during operation by 30%-50%, the NVH of the entire system is improved.

According to a preferred embodiment of the invention, a through hole is provided coaxially with the central axis of the output shaft of the differential. Preferably, two through holes are symmetrically disposed with respect to the central axis of the output shaft of the differential. The number of through holes and the diameter can be set according to the strength requirements of the one-axis and the vibration requirements. If the number of through holes is too large or the diameter is too large, the strength of the word axis will be affected. If the number of through holes is too small and the diameter is too small, the vibration cannot be reduced. Therefore, it is necessary to measure a balance point between meeting the strength requirement and minimizing the vibration. Based on a large amount of experimental data, the "equilibrium point" in the design of the present invention is that two through-holes symmetric about the central axis of the differential are provided, and one of the through-holes is in the middle of the differential to the differential The distance of the axis is one third of the distance from the central axis to the planet gears. Preferably, the diameter of the through holes does not exceed one third of the diameter of the one-word axis. This design can not only meet the strength requirements of the system for the word axis, but also significantly reduce the vibration of the word axis during operation.

According to a further preferred embodiment of the invention, a guiding groove for guiding the lubricating oil is arranged on the connecting section of the word shaft.

The technical problem can also be solved by a differential for a vehicle having a word axis comprising the above features.

DRAWINGS

Figure 1 shows a perspective view of a differential according to the present invention;

Figure 2a shows a front view of a differential according to the invention;

Figure 2b shows a cross-sectional view taken along line AA of Figure 2a;

Figure 3 shows a front view of a word axis in accordance with the present invention.

The same and functionally similar components use the same reference numerals.

detailed description

Figure 1 shows a differential 1 according to the invention, Figure 2a shows a front view of the differential, and Figure 2b shows the section taken along the line AA in Figure 2a. Sectional view. As shown, the differential according to the present invention includes a differential case 2, a driven bevel gear 7, two planetary gears 3, two side gears 4, and a bearing 6 for supporting the differential. The transmission system of the vehicle transmits torque from the drive system to the driven bevel gear 7. Since the driven bevel gear 7 and the differential housing 2 are fixedly connected by fasteners, such as bolts, the driven bevel gear 7 drives the differential The housing 2 is rotated. As shown in Fig. 2b, in the differential 1, the two planetary gears 3 are fixed using a word shaft 5. A through hole 11 is provided on one end side of the slot shaft, and the spindle shaft 5 can be fixedly coupled to the differential case 2 by means of the bolt 13. Therefore, the differential case 2 can drive the inline shaft 5, thereby driving the planetary gear 3, and then the planetary gear 3 transmits the torque to the side gear 4, and finally drives the output shaft to rotate.

A front view of a word axis in accordance with the present invention is shown in FIG. As shown, the inline shaft has a cylindrical shape and can be divided into an end section 10, a connecting section 9, an intermediate section 8, a connecting section 9 and an end section 10 in order from the top to the bottom in the axial direction. . The connecting section 9 is used to connect and fix the planetary gears 3. The through hole 11 is provided on one of the end sections 10, although it is of course also possible to provide through holes in both end sections 10. According to an embodiment of the invention, two equally sized through-openings 12 are provided on the intermediate section, which are symmetrical about the central axis of the differential 1 and extend in parallel with the through-openings 11. The diameter d of the through hole 12 is approximately equal to 1/3 of the diameter c of the i-axis. The distance b from the center of the through hole to the central axis is approximately 1/3 of the distance a from the top of the planetary gear to the central axis (as shown in Figure 2b). Furthermore, guide grooves 14 for guiding the lubricating oil are provided on the two connecting sections 9 respectively.

While a possible embodiment is exemplarily described in the above description, it should be understood that there are many variations of the embodiments in the combination of the technical features and embodiments that are readily apparent to those skilled in the art. In addition, it should be understood that the exemplary embodiments are merely by way of example, and are not intended to limit the scope of the invention. The above description is intended to provide the skilled person with a technical guide for the transformation of at least one exemplary embodiment, wherein various changes can be made without departing from the scope of the claims, particularly Changes in the function and structure of the components.

List of reference signs

1 differential

2 housing

3 planetary gears

4 semi-axle gear

5 word axis

6 bearing

7 driven bevel gear

8 middle section

9 connecting section

10 end section

11 through holes

12 through holes

13 fasteners

14 guiding slot

a distance

b distance

c diameter

d diameter

Claims

a spindle (5) for a differential (1) for connecting two planet gears (3) of the differential (1), wherein The inline shaft (5) has a cylindrical shape, and the in-line axis (5) is divided into an intermediate portion (8) in the middle, and on both sides of the intermediate portion for respectively a connecting section (9) of the planetary gear connection and an end section (10) adjoining the connecting section on each of the two end sides, wherein one of the end sections of the one-axis is arranged a radially extending through hole (11) fixedly coupled to the housing (2) of the differential by a fastener (13) passing through the through hole, characterized in that One or more through holes (12) are provided in the intermediate section (8) of the spindle (5).
The inline shaft (5) according to claim 1, characterized in that a through hole (12) is provided coaxially with the central axis of the output shaft of the differential.
The inline shaft (5) according to claim 1, characterized in that two of said through holes (12) are symmetrically arranged with respect to a central axis of an output shaft of said differential.
The inline shaft (5) according to claim 3, wherein a distance (b) from a central axis of a through hole (12) to the central axis is the central axis to the planetary gear (4) The distance of (a) is one third.
The inline shaft (5) according to any one of claims 1 to 3, characterized in that the diameter of the through hole (12) is set in accordance with the strength requirement for the one-word axis.
The inline shaft (5) according to claim 3 or 4, characterized in that the diameter (d) of the through hole (12) does not exceed one third of the diameter (c) of the inline axis.
The inline shaft (5) according to claim 1, characterized in that a guiding groove (14) for guiding the lubricating oil is arranged on the connecting section (9).
A differential for a vehicle, characterized in that the differential has a spindle according to any of the preceding claims.