Lift cabin stability control system - uses ball inclinometer to provide switching for control and alarm circuits

摘要

A control circuit prevents operation of the lift if the angle of inclination of the cabin floor exceeds predetermined values and is signalled by an alarm. A stability sensor comprises a light alloy plate (1) which is screwed to the lift cabin floor. A high precision stainless steel ball (6) is housed in a conducting cuvette (4) mounted on the plate by an insulated washer (3). A second insulated washer (8) allows a stainless steel plate (7) in four segments to be mounted above the ball. The assembly is covered by a cap (9). As the cabin floor tilts the ball moves to make contact with a segment to provide switching for an electronic circuit (12). This contains a gating circuit whose output drives a relay driver transistor to operate audible or visible alarms.