Remote monitoring of elevator cab lights
AssigneeOtis Elevator Company
InventorsTimothy M. Remmers, Barry G. Blackaby, William A. Wurts, William C. Rogers
Life of this patent
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Abstract
To sense the level of light in the passenger compartment 7 of an elevator cab 8, light at the proximal end of an optical fiber 4 is monitored by an optical detector 25 feeding a variable voltage divider 18, which allows setting a trip point at a desired level of light within the passenger compartment, thereby providing a signal indicating whether the light is adequate or not to a remote elevator monitoring apparatus 23. The trip point may be selected on installation by adjusting a potentiometer while watching an optical indication 17 of reaching the trip point, or it may be determined by software routines.
Claims9
Apparatus for monitoring the level of light in an elevator cab, comprising:
- an elevator cab having light fixtures for illuminating a passenger usage portion of said cab;
- an optical fiber having a distal end extending into a field of light provided by said light fixtures within said cab;
- an optical detector disposed adjacent a proximal end of said optical fiber for providing a light level signal indicative of the level of light in said cab;
- and
- level responsive means responsive to said light level signal for providing a trip signal indicative of whether the level of light in said passenger compartment is above a threshold level, or not.
Dependencies are inferred from the claim text.