Brush assembly for electric commutator motors
US4791331A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Apr 14, 1987 |
| Grant date | Dec 13, 1988 |
| Priority date | — |
| Expiry date | Apr 14, 2007 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01R39/18
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
The contact surface (8') is constantly urged against the commutator (9) by spring means. The brush material is progressively worn away, without changing the shape of the contact surface (8'), owing to the rotation of the commutator (9). A cylindrical slot (17) separates the outer portion (5') of the brush body (5) from the inner portion (5b) thereof. Thus, the contact surface (8') is kept separated from the cylindrical portion (16') of the outer surface of the brush body as long as the brush material is not worn away to reach the merging zone of the portions (5a) and (5b) of the brush body. This allows a substantial limitation of the risk of sparking between the brush body and the commutator to be achieved, thus avoiding deposit of a carbon layer onto the peripheral surface of the commutator.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.