Grounding mechanism for electric motor
US8183727B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Nov 24, 2008 |
| Grant date | May 22, 2012 |
| Priority date | — |
| Expiry date | Jan 3, 2030 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF16C41/002
- WIPO fieldMechanical elements
- WIPO sectorMechanical engineering
Abstract
An electric motor such as an AC induction electric motor includes a rotor having a rotor core and a rotor shaft. The rotor shaft defines an axially extending bore which has an electrical grounding ring positioned therein. The electrical grounding ring has an inertia insensitive configuration and forms a relatively low resistance electrical circuit segment between the rotor shaft and an electric motor housing to ground the electric motor rotor. The electric motor includes an oil lubricated bearing for the rotor shaft, and a sealing member such as a lip seal is positioned within the axially extending bore to inhibit lubricating oil intrusion therein. A non-rotating stub shaft may be mounted in the housing and extends into the axially extending bore to fluidly seal with the sealing member and electrically connect with the electrical grounding ring, which is fixed to rotate with the rotor shaft.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.