Sliding brush system with shape memory alloy element for two-speed direct current motor
US5734219A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jun 17, 1996 |
| Grant date | Mar 31, 1998 |
| Priority date | — |
| Expiry date | Jun 17, 2016 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH02K11/026
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A brush system for providing an electric connection to a rotating commutator wheel of an electric machine is disclosed. The brush system has a switched brush selectively switchable between an engaged position and a disengaged position and a switch connected to the switched brush and formed of a shape-memory-alloy. The switch attains an extended state at a first temperature and attaining a retracted state at a second temperature, for switching the switched brush alternately to the respective engaged position and the respective disengaged position. The switch includes a temperature conditioner for varying a temperature at the switch between the first temperature and the second temperature. The temperature condition may be an electric network wherein the internal resistance of the switch allows for heating of the switch to the second temperature.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.