Safety relay
US6236553A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Aug 3, 1999 |
| Grant date | May 22, 2001 |
| Priority date | — |
| Expiry date | Aug 3, 2019 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01H47/005
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A safety relay for supervising and ensuring safe operation of a machine industrial process and corresponding safety devices and actuators. The safety relay has at least one input, which is monitored for short circuits and open circuits, for connection to said safety devices and actuators, at least one output for connection to said machine or process, one or more than one stop relay for maintaining and interrupting, respectively, the connection to said machine or process depending on a momentary status of said safety devices and actuators, and a reset circuit with at least one capacitor and a reset input. The capacitor receives and stores electrical energy in a first state, while discharging the electrical energy in a second state for resetting the safety relay to a normal state of operation. The safety relay also has first means connected to the capacitor, the first means establishing, in a first state, a closed current path between a first and second supply conductor for charging the capacitor, and, in the second state, the first means isolating the capacitor from the second supply conductor. Second means are arranged in parallel to the capacitor for conducting current, in the sec…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.