Apparatus and method for protecting a motor control circuit
US4691149A · kind A · utility
19Cited by
15References
3Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Oct 11, 1985 |
| Grant date | Sep 1, 1987 |
| Priority date | — |
| Expiry date | Oct 11, 2005 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S388/92
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
Motor control circuits having solid-state switching elements are commonly used on industrial vehicles such as lift trucks. A short circuit condition in the motor circuit can cause catastrophic failure of the semiconductor switching element. The instant invention detects such a short circuit condition and modifies the motor control signals supplied by a chopper circuit to a switching element. The apparatus includes a trigger circuit for receiving the motor control signals and sensing a voltage across the motor produced in response to electrical power delivered from a power supply.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.