LIFT SAFETY DEVICE Russian patent published in 1994 - IPC

FIELD: safety devices. SUBSTANCE: device has switch contacts of shaft and cabin doors, the contacts are shunted by resistors which are one of the bridge arms, and three resistors which are three other bridge arms, and a lift door condition checking unit. The lift door condition check unit has three current-limiting resistors, three threshold elements, six controllable keys, a bridge condition check unit, an actuator with break and make contacts, delay elements and a storage element. EFFECT: improved safety. 1 dwg