Interface circuit for interconnecting an electronic controller to a resistance welding machine
US4251764A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Apr 26, 1979 |
| Grant date | Feb 17, 1981 |
| Priority date | — |
| Expiry date | Apr 26, 1999 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S323/907
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
An interface circuit is provided for interconnecting an electronic controller to a contactor circuit which, in turn, controls the alternating current flow from an alternating current power source to controlled equipment, such as a resistance welding machine. The contactor circuit, for example, includes a pair of semiconductor switching devices, such as silicon controlled rectifiers (SCR)s, the two semiconductor switching devices are alternately rendered conductive during successive half-cycles of the alternating current power from the alternating current power source at times controlled by the controller for the controlled operation of the welding machine. The interface circuit includes means for monitoring the junction temperature of each of the semiconductor switching devices, and to provide an indication and a control effect should the junction temperature exceed a particular safe threshold.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.