Photoelectric light curtain using retroreflector

Details Photoelectric light curtain using retroreflector Photoelectric light curtain using retroreflector

1979-01-23

1980-12-16

Nelms, David C.

Radiant energy

Photocells; circuits and apparatus

Optical or pre-photocell system

340556, G01D 2104

Patent

active

042399610

ABSTRACT:
A low-cost photoelectric machine access safety device is technically disclosed in the specification and drawings comprising an integral support structure supporting a retrodirective reflective (RDR) material facing an enclosed area which is to be guarded. A rotatable mirror causes a light beam from a reflex photohead to scan the guarded area. The RDR material reflects the light beam back along the transmitted path at varying angles of incidence. A photocell in the reflex photohead is activated to operate a control circuit to keep a control relay energized. Upon any interruption of the scanning light beam the relay is deenergized causing the accessed machine to stop. False operation preventing means prevents false operation when the light beam is scanning the portion of the support structure on which the rotatable mirror and associated apparatus is mounted. Fail-safe circuitry is also disclosed.

REFERENCES:
patent: 2769374 (1956-11-01), Sick
patent: 3360654 (1967-12-01), Muller
patent: 3805064 (1974-04-01), Kornylak
patent: 4107522 (1978-08-01), Walter
patent: 4127771 (1978-11-01), Sick

Affiliated with

Also associated with

Rating

Photoelectric light curtain using retroreflector does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Photoelectric light curtain using retroreflector, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Photoelectric light curtain using retroreflector will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFUS-PAI-O-609637