Bilevel flame signal sensing circuit
US4375951A · kind A · utility
5Cited by
10References
11Claims
0Family size
Assignee
Inventor
Key dates
| Filing date | Aug 18, 1980 |
| Grant date | Mar 8, 1983 |
| Priority date | — |
| Expiry date | Aug 18, 2000 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF23N2235/18
- WIPO fieldThermal processes and apparatus
- WIPO sectorMechanical engineering
Abstract
A fuel burner control system that has a fail safe mode of operation utilizes a flame sensing means that controls two separate signal processing circuits that have two different threshold levels of operation. Each of the signal processing circuits controls a separate switch means and these switch means are interrelated to ensure that a pilot valve and main valve are opened in sequence and that a pilot flame is properly burning before the main valve is opened. If the flame sensing means for the device senses any abnormality, the interrelationship of the output circuits prevents the main valve from opening.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.