Abstract: The invention concerns a frequency converter-controlled squirrel cage motor particularly for use in elevator operation. The motor's stator is mounted on a stationary axle and the rotor rotating around the stator has been rotatably carried on the same axle. On the outer periphery of the rotor a cylinder has been mounted, carrying rope grooves and a brake surface for the elevator's lifting ropes and brake.

Abstract: The invention concerns, first, a signalling procedure for a lift, whereby the control system and the users of the lift are informed on lift calls and the state of the lift, e.g. position, movement and availability, by using serial communication between the control system computer and the actuating and signalling means in the lift car and on each floor level, and, second, a signalling system applying the said procedure. To avoid abundant and complicated wiring and to increase standardization in the design of the lift system main panel and call button stations, the signalling system of the invention employs the polling principle in its internal communication, whereby data are transmitted bi-directionally using digital series loops, one of which connects the devices in the lift car, controlled by and communicating via a microprocessor, another connects the corresponding shaft and door devices, while a third loop is used for communication with the external world.