Abstract: An elevator relevelling control apparatus for controlling the movement of an elevator car (11) such that when the car is misaligned with the landing position of a selected landing floor, the car is restarted and brought into alignment. A traction motor (M) is controlled by a landing means (1) which generates a speed command signal (1a) of a magnitude which increases linearly with the extent of misalignment. First and second position detecting devices (15, 16, 17, 18) are provided in the hoistway to detect misalignment from the landing position by a first or second predetermined distance, respectively. The car is provided with load detecting means (12) for detecting whether or not the car is overloaded. If the load detecting means (12) detects that the car is not overloaded, and a switching device (15, 16) detects that the car is misaligned by a first predetermined distance, a speed command signal (1a) of suitable magnitude is supplied to the traction motor (M), thereby effecting relevelling.

Abstract: A device for grounding an elevator winder including an electric motor controlled by a semiconductor switching element and a first rotary element coupled to the electric motor. A main rope is wound on the first rotary element and bearings are adapted to support the electric motor and first rotary element. A first grounding circuit grounds the bearings through a resistor and a second grounding circuit grounds the main rope without using a resistor. The main rope may also be wound around a second rotary element.

Abstract: A control system for a D.C. electric motor utilizing a Ward-Leonard rotation speed control system in which noise components in the input power to the motor are substantially eliminated. Switching means in the form of gate turning-off thyristors couples a delta-connected capacitance circuit to the input line to the motor between inductors coupled in series with each phase of the input line. Switching means is provided which is opened after a predetermined time delay from the firing time of the thyristor converter. The time delay is preferably approximately one-fourth of the system natural oscillation period.

Abstract: An elevator traction machine including a main rope, a traction sheave, a DC motor controlled by a thyristor Leonard system, a brake wheel, bearings of motor shaft and a machine beam.The motor shaft is grounded through first grounding circuit including a current collector for the shaft current induced by the switching operation of the thyristor, and through second grounding circuit including the bearings. The second grounding circuit includes a resistor to substantially prevent the flow of the shaft current through the bearings and to protect the bearings from the electrolytic corrosion.

Abstract: An emergency stop apparatus for electric elevators which comprises a DC motor for driving a cage and being controllingly driven by variable DC power source connected to an AC power source, a power stoppage memorizing circuit which detects the power stoppage of the AC power source and memorizes the power stoppage, a motor stopping circuit for stopping the motor when the power stoppage memorizing circuit operates, and a memory erasing circuit for erasing the memory for the memorizing circuit after the cage stops. In the apparatus, a start command issued through the operation from a floor or the cage inside releases the motor stopping circuit to permit the cage to restart its travel.

Abstract: A control device for an elevator, which is made up of a position detecting device for detecting the position at which rotary elements such as the armature of an electric motor and sheaves produce vibration torque and a cancellation signal generating circuit. The circuit is employed for generating a cancellation signal to cancel the vibration torque in response to the output of the position detecting means. A control circuit is used for applying current necessary for cancelling the vibration torque to the motor by receiving the cancellation signal. Even if the vibration is caused by the eccentricity of the rotary elements or by the torque ripples generated by the armature of the motor, it is not sensed by the persons in the elevator cage.

Abstract: A speed control apparatus for elevator system which controls a speed of a cage through a main rope under controlling a motor by a speed control system comprising an acceleration feedback circuit, comprises a detection circuit for detecting a speed or a position of the cage which is vibrated under corresponding a frequency of an outer disturbance to a resonance frequency of the main rope and a command circuit for increasing a gain of the acceleration feedback circuit by the output of the detection circuit.

Abstract: A deceleration controlling apparatus for an elevator is to prevent excess regenerative current by applying a friction type brake at a specific intensity to a motor for driving a cage during an abnormal deceleration at speed of the cage that is faster than the normal speed for the terminal floor deceleration by a failure in landing the cage on the terminal floor.

Abstract: An elevator control apparatus comprises a thyristor power rectifier connected to an AC power source and for driving a DC motor for cage drive; a power stoppage detector for detecting the power stoppage of the AC power source; and a series circuit including a capacitor and switching connected in series with the capacitor. The series circuit is connected across the thyristor power rectifier. Before a cage starts its travel, the capacitor is charged through the thyristor power rectifier, with the polarity which depends on the traveling direction of the cage. At the power stoppage, the capacitor is discharged through the thyristor power rectifier, in response to a switching operation of the switching element.

Abstract: An elevator landing control apparatus comprises a cage and a counter-weight which are suspended by a main rope in a hoistway; a winding motor which drives a driving sheave; a brake for holding the cage by holding the motor during the stop of the cage; a landing device or a cage acceleration control circuit; a lower floor detecting circuit and a door open detecting circuit and a control circuit which releases the holding of the motor by the brake and actuates the landing device or the cage acceleration circuit when the lower floor detecting circuit and the door open detecting circuit are in the actuated condition.

Abstract: The disclosed Leonard type elevator system comprises a reversible converter for controllably driving a DC motor, and an AC voltage detector and a DC voltage detector connected to the AC and DC sides of the converter respectively for detecting the voltages developed on the respective sides of the converter. When a difference in detected voltage between the two detectors exceeds a predetermined magnitude due to a decrease in the AC source voltage, a comparator produces an output serving to disconnect the DC motor from the converter. Also the comparator may produce such an output when the converter receives regenerative power from the DC motor.

Abstract: An armature of an electric motor for an elevator car is controllably driven by a three-phase source through a semiconductor converter controlled with a difference between a command and an actual car speed signal. A relay for sensing a ripple current from the converter is serially connected to a tuned filter across the armature. When a break occurs anywhere in a circuit with the motor armature, the sensor relay is deenergized and connects an emergency braking circuit across the armature. Alternatively the sensor relay may be connected via the filter to a reactor connected to the converter.

Abstract: A direct current motor for an elevator car includes an armature and an interpole winding or a series field winding serially connected to the armature and controlled by a static Ward-Leonard device. A filter includes the interpole or series field winding and a series combination of a capacitor, a resistor, a reactor and a fuse with or without a series reactor.

Abstract: An electric generator energizes a driving motor for an elevator car. In order to control the generator field, a control circuit compares a command speed signal with a sensed speed signal of the elevator car and applies the result of the comparison to the field through a filter of electrically higher order operative to cancel out a resonance and an antiresonance frequency of a mechanical system formed of the elevator car and associated mechanical components.