Fail safe gas furnace optical flame sensor using a transconductance amplifier and low photodiode current
US6060719A · kind A · utility
114Cited by
30References
10Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Jun 24, 1997 |
| Grant date | May 9, 2000 |
| Priority date | — |
| Expiry date | Jun 24, 2017 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF23N5/082
- WIPO fieldThermal processes and apparatus
- WIPO sectorMechanical engineering
Abstract
A fail safe gas furnace optical flame sensor uses a transconductance amplifier with low photodiode current to sense the presence or absence of a gas flame within the burner of a gas furnace. The photodiode signal appears as the only negative voltage signal in the circuit, and the equivalent resistance feedback network is redundantly designed, thus ensuring that no false flame-on conditions will be detected due to the failure of a single resistive component. Because it does not reside within the flame, the sensor is immune to false flame-off conditions caused by material deposition and corrosion of the sensor.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.