Drive device for a motor vehicle

Patent metadata

Field	Value
Publication number	US-10840779-B2
Application number	US-201916254707-A
Country	US
Kind code	B2
Filing date	Jan 23, 2019
Priority date	Sep 6, 2016
Publication date	Nov 17, 2020
Grant date	Nov 17, 2020

Abstract

A drive device for a motor vehicle includes at least one electric machine and at least one shaft, which shaft is rotatably mounted on a housing element of the drive device and can be driven by the electric machine. At least one discharge ring is provided by which the shaft is brought into electrical contact with the housing element in order to dissipate electrical charges from the shaft to the housing element via the discharge ring. The discharge ring is formed from an electrically conductive fluid.

First claim

What is claimed is:

1. A drive device for a motor vehicle, comprising:
a housing element of the drive device;
at least one electric machine;
at least one shaft which is mounted rotatably on the housing element of the drive device and is drivable via the electric machine; and
at least one discharge ring containing an electrically conductive fluid, via which the shaft is brought into electrical contact with the housing element in order to dissipate electrical charges from the shaft to the housing element via the electrically conductive fluid of the discharge ring, wherein
the discharge ring is at least partially arranged in a receptacle of the housing element and at least partially accommodated in a corresponding annular receptacle of the shaft.

2. The drive device as claimed in claim 1 , further comprising:
an inverter to supply a voltage to the electric machine and to act as a common-mode source which induces the electrical charges in the shaft.

3. The drive device as claimed in claim 2 , wherein the voltage is an a.c. voltage.

4. The drive device as claimed in claim 1 , further comprising:
a mounting, via which the shaft is mounted rotatably on the housing element, wherein
the discharge ring is a component which is different from the mounting and is provided in addition thereto.

5. The drive device as claimed in claim 4 , wherein
the discharge ring directly touches the shaft and/or the housing element.

6. The drive device as claimed in claim 1 , wherein the discharge ring directly touches the shaft and/or the housing element.

7. The drive device as claimed in claim 1 , wherein the fluid comprises an ionic liquid.

8. The drive device as claimed in claim 5 , wherein
the fluid comprises an ionic liquid.

9. A motor vehicle, comprising at least one drive device as claimed in claim 1 .

10. A drive device for a motor vehicle, comprising:
a housing element of the drive device;
at least one electric machine;
at least one shaft which is mounted rotatably on the housing element of the drive device and is drivable via the electric machine; and
at least one discharge ring containing an electrically conductive fluid, via which the shaft is brought into electrical contact with the housing element in order to dissipate electrical charges from the shaft to the housing element via the discharge ring, wherein
the discharge ring is at least partially accommodated in an annular receptacle of the shaft formed by a circumferential groove.

11. The drive device as claimed in claim 10 , further comprising:
a mounting, via which the shaft is mounted rotatably on the housing element, wherein
the discharge ring is a component which is different from the mounting and is provided in addition thereto.

12. The drive device as claimed in claim 10 , wherein
the discharge ring directly touches the shaft and/or the housing element.

Assignees

• Bayerische Motoren Werke Ag

Inventors

• Reuter Martin
• Grom Alfred

Classifications

• H02K11/40 Primary

  Structural association with grounding devices · CPC title

• H02K7/003

  Couplings; Details of shafts (means for mounting rotors on shafts H02K1/28) · CPC title

• B60Y2200/92

  Hybrid vehicles · CPC title

• H01R39/646

  through an electrical conductive fluid · CPC title

• B60L50/00

  Electric propulsion with power supplied within the vehicle (with power supply from force of nature, e.g. sun or wind, B60L8/00; for monorail vehicles, suspension vehicles or rack railways B60L13/00) · CPC title