Patent ID: 11964848
Assignee: OTIS ELEVATOR COMPANY
Field: Handling (Mechanical engineering)
Classification: CPC B | IPC B

Claim 0:
1. An elevator system comprising:
a hoistway;
an elevator car configured to travel in the hoistway;
a pit located at a bottom of the hoistway;
a safety chain configured to enable or disable motion of the elevator car;
a sensor assembly configured to initiate opening the safety chain to disable motion of the elevator car upon detection of a person in a detection region of the sensor assembly in the hoistway; and
a test device configured to test operation of the sensor assembly to detect malfunctioning and/or tampering of operation of the sensor assembly;
wherein the test device is configured to place a known background across a field of view of the sensor assembly such that the sensor assembly evaluates the known background to test functionality of the sensor assembly.