Abstract: In an elevator system in which the elevator cars are moved by a hoist motor with a brake and the hoist motor is energized by controls to cause energization of the motor, movement of a car and release of the brake, motor protecting circuits which are time rather than current magnitude responsive. One protective circuit includes a time delay relay which is activated upon energization of the motor and which causes deenergization of the motor if the motor is energized longer than the time it normally takes a car to travel from the lower floor to the upper floor or vice versa. The other protective circuit includes a time delay relay which is activated when the motor is energized and the brake fails to release and which cause deenergization of the motor if the brake fails to release within a predetermined time. Either circuit may be used alone. Also, an indicator to indicate operation of a time delay to deenergize the motor.

Abstract: In an automatic elevator system which has a plurality of elevator cars, manually operable buttons at floors to register hall calls and control circuits for controlling the movement of the elevator cars, the improvement which includes time delay circuits intermediate the buttons and the control circuits for causing the control circuits to recognize the registration of a hall call but which will delay the response of the control circuit, and hence, the stopping of a car at the floor at which a hall call has been registered, until a predetermined time after such hall call has been registered.

Abstract: A door interlock switch is provided for an elevator. The switch means is mounted in a housing adjacent the door, the housing having an opening which permits the entrance of a permanent magnet actuating means. A barrier is mounted in the housing to prevent access to the switch by mechanical devices but which will permit the switch to be operated by the permanent magnet.

Abstract: Safety controls for an elevator car in which a switch which is closed when the elevator car door is at least partly open is connected to a relay which interrupts the power to the motor of the car hoisting apparatus when the car speed exceeds a safe value. The switch and relay are connected in series to the hoisting apparatus motor armature, the voltage on which is proportional to the speed thereof and alternatively may be connected in series with a centrifugal switch driven by the hoisting apparatus motor. The relay may also actuate the motor brake and may be included in a lockup circuit which is manually resettable by an attendant.

Abstract: An elevator control modifying system which detects the existence of a call registered by a passenger in an elevator car and, until delivery of the registering passenger to the call destination, automatically prevents stopping of the elevator for calls registered at intervening landings and to which the car would normally respond. Upon delivery of the car passenger at the designated floor, the control is automatically conditioned to respond to calls registered at landings. Optionally, high call reversal, if present, is restricted to effective car calls when such a call is registered by the car passenger.