Photo transducer circuit for setting minimum and maximum current flow between power terminals
US4538063A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Jan 5, 1983 |
| Grant date | Aug 27, 1985 |
| Priority date | — |
| Expiry date | Jan 5, 2003 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01L9/0032
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A photo transducer circuit (30) selectively controls the current which is transmitted between power terminals (32, 34). A light emitter (20) transmits light to a first photo receiver (24) and a second photo receiver (26). A vane (16) is movable by a Bourdon tube (12) to permit a variable amount of light to pass from the photo emitter (20) to the photo receiver (26). The output of the photo emitter (20) is regulated by a circuit which monitors the output of the photo receiver (24). Circuitry is provided to set a minimum current flow between the power terminals (32, 34) when the vane (16) substantially blocks illumination of the photo receiver (26). Further circuitry is provided to set a maximum current flow between the power terminals (32, 34) when the vane (16) allows substantial exposure of the photo receiver (26) to the light produced by emitter (20). The current passed between the power terminals (32, 34) is proportional to the degree of blockage of the light from the emitter (20) directed toward the photo receiver (26).
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.