Safety device for combined ventilator/light unit
US5021932A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | May 17, 1989 |
| Grant date | Jun 4, 1991 |
| Priority date | — |
| Expiry date | May 17, 2009 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF24F13/078
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
Two thermal protectors or thermostatic sitches are mounted on the outside of the housing of a combination ventilator/lamp unit to sense any heat build-up in the housing during operation of its lamp. One switch is normally open and is connected between the lamp and the motor for the ventilator fan; and the other switch, which is normally closed, is connected in series with the fan motor and lamp. The normally open switch is set to close automatically when the temperature in the housing reaches a first value above room temperature, thereby to energize the fan motor to cool down the housing. If the normally open switch and/or the fan motor fails the normally closed switch is set to open at a temperature above that at which the normally open switch closes, and functions as a safety switch to disconnect both the fan motor and lamp from the power supply.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.