Method and apparatus optically coupling thermostat to control a fan
US6357667B1 · kind B1 · utility
Assignee
Inventor
Key dates
| Filing date | Aug 2, 2000 |
| Grant date | Mar 19, 2002 |
| Priority date | — |
| Expiry date | Aug 2, 2020 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY02B30/70
- WIPO fieldControl
- WIPO sectorInstruments
Abstract
An electrical circuit for controlling the activation of a fan includes optically coupled isolators. The circuit is electrically connected in series to a thermostat including a bimetal actuated contact with an anticipator across the contact. Power to the circuit is provided by voltage developed across the system relay coil in series with the thermostat. A zener diode establishes a threshold voltage consistent with the operation of the system relay coil and the thermostat. The optically coupled isolators provide the required electrical isolation needed to protect the thermostat from a power control circuit of an electronically controlled fan.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.