Transmission for a motor vehicle, and electric axle drive

Patent metadata

Field	Value
Publication number	US-11635133-B2
Application number	US-202117494328-A
Country	US
Kind code	B2
Filing date	Oct 5, 2021
Priority date	Oct 6, 2020
Publication date	Apr 25, 2023
Grant date	Apr 25, 2023

Abstract

A transmission (G) for a motor vehicle includes a housing (GG), a shaft (W, GW 2 , DS 1 , DS 2 ) mounted in the housing (GG) and protruding from the housing (GG), a radial shaft seal (DR) having a sealing lip for sealing an oil space (NR) within the housing (GG) with respect to an exterior, a shaft grounding device (E) arranged on an exterior side of the radial shaft seal (DR) for establishing an electrically conductive sliding contact (SK) between the shaft (W, GW 2 , DS 1 , DS 2 ) and the housing (GG), and a sleeve-shaped covering element (C) fixedly connected to the shaft (W, GW 2 , DS 1 , DS 2 ) for protecting the sliding contact (SK) against environmental influences. The shaft grounding device (E) is fixedly connected to the housing (GG). The covering element (C), together with the grounding device (E), forms a labyrinth sealing. An electric axle drive (EA) may include the transmission (G).

First claim

The invention claimed is:

1. A transmission (G) for a motor vehicle, comprising:
a housing (GG);
a shaft (W, GW 2 , DS 1 , DS 2 ) mounted in the housing (GG) and protruding from the housing (GG);
a radial shaft seal (DR) comprising a sealing lip for sealing an oil space (NR) within the housing (GG) with respect to an exterior;
a shaft grounding device (E) arranged on an exterior side of the radial shaft seal (DR), the shaft grounding device (E) configured for establishing an electrically conductive sliding contact (SK) between the shaft (W, GW 2 , DS 1 , DS 2 ) and the housing (GG); and
a sleeve-shaped cover (C) fixedly connected to the shaft (W, GW 2 , DS 1 , DS 2 ), the cover (C) configured for protecting the sliding contact (SK) against environmental influences,
wherein the shaft grounding device (E) is fixedly connected to the housing (GG), and the cover (C) and the shaft grounding device (E) collectively form a labyrinth sealing.

2. The transmission (G) of claim 1 , wherein the cover (C) comprises an axially aligned section (C 1 ) that encompasses an axial projection (E 1 ) of the shaft grounding device (E).

3. The transmission (G) of claim 2 , wherein a radial gap (SP 1 ) is defined between the axially aligned section (C 1 ) of the cover (C) and the axial projection (E 1 ) of the shaft grounding device (E).

4. The transmission (G) of claim 1 , wherein the cover (C) comprises a radially aligned projection (C 2 ).

5. The transmission (G) of claim 4 , wherein a radial gap (SP 2 ) is defined between the radially aligned projection (C 2 ) of the cover (C) and the housing (GG).

6. The transmission (G) of claim 4 , wherein:
the cover (C) comprises an axially aligned section (C 1 ) that encompasses an axial projection (E 1 ) of the shaft grounding device (E); and
the radially aligned projection (C 2 ) of the cover (C) adjoins the axially aligned section (C 1 ) of the cover (C).

7. The transmission (G) of claim 1 , wherein the cover (C) is attached on a diameter of the shaft (W) that is larger than a diameter of the sliding contact (SK).

8. The transmission (G) of claim 1 , wherein a surface of the cover (C) forms a shaft-side running surface of the sliding contact (SK).

9. The transmission (G) of claim 1 , wherein the sliding contact (SK) of the shaft grounding device (E) comprises a brush or electrically conductive PTFE elements.

10. The transmission (G) of claim 1 , wherein the shaft (W) comprises an output shaft of the transmission (G).

11. The transmission (G) of claim 1 , further comprising an electric machine (EM) and a power converter (INV) associated with the electric machine (EM).

12. The transmission (G) of claim 1 , wherein the transmission (G) is a planetary automatic transmission, a dual-clutch transmission, an automated transmission, or a CVT transmission.

13. An electric axle drive (EA) for a motor vehicle, comprising the transmission (G) of claim 1 .

Assignees

• Zahnradfabrik Friedrichshafen

Inventors

• Griesbach Michael
• Müller Thorsten

Classifications

• H02K11/40 Primary

  Structural association with grounding devices · CPC title

• H01R39/34

  Connections of conductor to slip-ring · CPC title

• H02K15/16

  Centring rotors within the stators · CPC title

• F16C41/002

  Conductive elements, e.g. to prevent static electricity · CPC title

• H02K5/10

  with arrangements for protection from ingress, e.g. water or fingers · CPC title