Differential gear for a motor vehicle

Patent metadata

Field	Value
Publication number	US-11353100-B2
Application number	US-201917286136-A
Country	US
Kind code	B2
Filing date	Oct 31, 2019
Priority date	Nov 22, 2018
Publication date	Jun 7, 2022
Grant date	Jun 7, 2022

Abstract

A differential gear including a rotatably mounted differential housing and a final driven gear mounted rotationally fixed to the differential housing. The differential housing, on the outer circumferential surface thereof, includes two mating surfaces and that the final driven gear, on the inner circumferential surface thereof, includes two radially opposite mating surfaces. The mating surfaces formed on the outer circumferential surface of the differential housing and the mating surfaces formed on the inner circumferential surface of the final driven gear are each designed as separate mating surfaces which, when viewed in axial direction (a), are arranged geometrically separated from each other by a spacing.

First claim

The invention claimed is:

1. A differential gear comprising a rotatably mounted differential housing and a final driven gear mounted rotationally fixed to the differential housing, wherein the differential housing, on an outer circumferential surface thereof, comprises two mating surfaces, wherein the final driven gear, on an inner circumferential surface thereof, comprises two radially opposite mating surfaces, wherein the mating surfaces formed on the outer circumferential surface of the differential housing and the mating surfaces formed on the inner circumferential surface of the final driven gear are each designed as separate mating surfaces which, when viewed in an axial direction (a), are arranged geometrically separated from each other by a spacing (A) and are located at a same radial distance from a rotational axis of the differential housing, wherein the final driven gear is pressed onto the differential housing, so that the final driven gear and the differential housing are connected to one another by means of a first press fit and a second press fit which is separate therefrom and axially separated by the spacing (A), and wherein at least one of the first press fit and second press fit is provided only as a frictional connection.

2. The differential gear according to claim 1 , wherein in the axial direction (a), the mating surfaces formed on the outer circumferential surface of the differential housing and the mating surfaces formed on the inner circumferential surface of the final driven gear are in each case separated from one another by a circumferential groove introduced into each respective circumferential surface, and wherein the grooves, when viewed in the axial direction (a), each have a length corresponding to the spacing (A).

3. The differential gear according to claim 2 , wherein the grooves have a rectangular, triangular or semicircular basic shape.

4. The differential gear according to claim 3 , wherein when viewed in the axial direction (a), the inner circumferential surface of the final driven gear has a length (L) and wherein, with respect to the length (L) of the inner circumferential surface, for the spacing (A) between the mating surfaces:
0.5≤ A/L≤ 0.7.

5. The differential gear according to claim 3 , wherein the two press fits have a radial overlap of 10 to 50 μm and wherein an additional non positive or positive locking connection is formed between the final driven gear and the differential housing.

6. The differential gear according to claim 3 , wherein the two press fits have a radial overlap of >200 μm, so that the final driven gear is connected in a rotationally fixed and axially fixed manner to the differential housing only via frictional connections resulting from the two press fits.

7. The differential gear according to claim 2 , wherein when viewed in the axial direction (a), the inner circumferential surface of the final driven gear has a length (L) and wherein, with respect to the length (L) of the inner circumferential surface, for the spacing (A) between the mating surfaces:
0.5≤ A/L≤ 0.7.

8. The differential gear according to claim 2 , wherein the two press fits have a radial overlap of 10 to 50 μm and wherein an additional non positive or positive locking connection is formed between the final driven gear and the differential housing.

9. The differential gear according to claim 2 , wherein the two press fits have a radial overlap of >200 μm, so that the final driven gear is connected in a rotationally fixed and axially fixed manner to the differential housing only via frictional connections resulting from the two press fits.

10. The differential gear according to claim 1 , wherein when viewed in the axial direction (a), the inner circumferential surface of the final driven gear has a length (L) and wherein, with respect to the length (L) of the inner circumferential surface, for the spacing (A) between the mating surfaces:
0.5≤ A/L≤ 0.7.

11. The differential gear according to claim 10 , wherein the two press fits have a radial overlap of 10 to 50 μm and wherein an additional non positive or positive locking connection is formed between the final driven gear and the differential housing.

12. The differential gear according to claim 1 , wherein the two press fits have a radial overlap of 10 to 50 μm and wherein an additional non positive or positive locking connection is formed between the final driven gear and the differential housing.

13. The differential gear according to claim 12 , wherein the additional connection is designed in the form of a weld connection.

14. The differential gear according to claim 13 , wherein
the weld connection is designed as a one-sided weld seam position arranged either only in a region of the first press fit or only in a region of the second press fit.

15. The differential gear according to claim 14 , wherein the weld connection is produced by electron or laser welding.

16. The differential gear according to claim 13 , wherein the weld connection is produced by electron or laser welding.

17. The differential gear according to claim 12 , wherein the additional connection is designed in the form of a polygonal or mating toothing and wherein, between the final driven gear and the differential housing, a retaining element preventing a relative movement in the axial direction (a) is arranged.

18. The differential gear according to claim 17 , wherein the retaining element is designed in the form of a retaining ring.

19. The differential gear according to claim 1 , wherein the two press fits have a radial overlap of >200 μm, so that the final driven gear is connected in a rotationally fixed and axially fixed manner to the differential housing only via frictional connections resulting from the two press fits.

20. The differential gear according to claim 1 , wherein the differential housing is made of cast iron and the final driven gear is made of a hardenable material.

Assignees

• Audi Ag

Inventors

• Hornung Kurt
• Schäfer Markus
• Merz Andrej

Classifications

• F16H48/38 Primary

  Constructional details (the outer casing comprising the differential and supporting input and output shafts F16H57/037) · CPC title

• F16H2048/382

  Methods for manufacturing differential gearings · CPC title

• F16D1/0858

  due to the elasticity of the hub (including shrink fits) · CPC title

• F16H48/40 Primary

  characterised by features of the rotating cases · CPC title

• F16D1/068

  involving gluing, welding or the like · CPC title