Mitsubishi Denki Kabushiki Kaisha

Hiroshi Kamaike

Nobuo Anzai

Shigehiko Suzuki

Narihiro Terazono

Hideo Uchino

A remote call registration system for an elevator including a transmitting device carried by a user and a receiving device disposed at a position near to but spaced a distance from the elevator hall. A signal transmitted from the transmitting device is received by the receiving device when the user is at a given walking distance from the elevator hall and sent to a call registration device to register the call prior to arrival of the user at the elevator hall. The distance between the receiving device and the elevator hall is predetermined to be substantially equal to the walking distance corresponding to a mean waiting time required for the cage to arrive at the hall after the call is registered by the call registration device. Thus, the user's waiting time at the elevator hall is substantially reduced.

Remote call registration system for elevator

An alternating current having a variable voltage and frequency which is converted by an inverter is supplied to an induction motor for driving an elevator so that a speed command value is decreased and the output frequency of the inverter is decreased at the energy saved operation. Thus, energy saved operation may be accomplished without adversing the efficiency even if the speed of the cage is decreased. Since the output voltage of the convertor is increased simultaneously with this, the power factor is improved so that saving in energy is furthermore enhanced.

System for controlling a motor

An elevator control apparatus wherein a primary current of an induction motor is controlled separately for a component parallel to a secondary interlinking magnetic flux and a component orthogonal thereto, comprising means to generate a correction signal having a predetermined frequency, phase and magnitude which cancel a magnetic flux ripple of the induction motor attributed to a shaft deflection of a hoisting machine caused by action of an elevator load, the correction signal from the means being superposed on either of the components parallel and orthogonal to the secondary interlinking magnetic flux so as to control the primary current. Thus, even when the shaft deflection is involved, a control free from any torque ripple is permitted, and an elevator of comfortable ride can be realized.

Elevator control apparatus

An apparatus for controlling an A.C. elevator comprising: A charging device, a discharging device, an inverter, current detecting means for detecting the current flowing between an A-C power supply and D-C batteries and through said charging and discharging devices, and a charging and discharging rate control circuit responsive to the output of said current detecting means for controlling the charging and discharging rates of said D-C batteries as the load conditions of the car of said elevator change so as to cause said charging and discharging of said batteries to be minimum so that the element of said batteries is not shortened.

Control apparatus for A.C. elevator

An automatic landing apparatus in service interruption comprises; an electromagnetic brake which is released to release a main motor for driving a cage; an auxiliary motor which is equipped together with the main motor to drive the cage; an emergency power source which has a power for releasing the electromagnetic brake and driving the auxiliary motor; a brake releasing circuit which maintains the releasing of the electromagnetic brake by the emergency power source when the service interruption of the normal power source is caused during the driving of the cage; and a restarting circuit which drives the auxiliary motor when the cage is not stopped at the door openable zone when the case is moved under releasing the electromagnetic brake whereby the case is moved by the actuation of the restarting circuit.

Automatic landing apparatus in service interruption

The disclosed elevator speed control system accelerates an induction motor for an elevator car in accordance with a voltage dependent upon a differential signal between a command speed signal and the actual speed signal and passed through a saturation generator. The saturation generator issues a command for applying across the motor its rated voltage upon the closure of a normally open contact set disposed in it. The system includes a sensor circuit is responsive to the difference signal less than a predetermined magnitude to decrease an output from the saturation generator. Alternatively the sensor circuit may responds to a negative load on the motor exceeding a predetermined magnitude to decrease the output from the saturation generator.

Elevator speed control system

In an elevator speed control system, the actual speed signal from an induction motor is subtracted from a command speed signal and then supplied to a nonlinear circuit. The circuit produces an output voltage approximately proportional to the square root of its input voltage. The output voltage is applied to three phase shifters, one for each phase of a three-phase system, to produce firing signals to control the conduction of associated thyristors resulting in the control of a three-phase voltage applied to the motor and therefore its rotational speed.

An apparatus for controlling the speed of an induction motor is disclosed which comprises an induction motor, a load coupled to the induction motor which has a negative polarity, a difference signal generating device for generating a difference signal between a signal corresponding to the speed of the load and a predetermined speed command signal, a signal converting device for presetting, prior to the deceleration of the load, a signal necessary to allow the motor to produce a rotating torque corresponding to the load, a voltage applying device for applying to the motor a voltage corresponding to the difference signal while the load is being accelerated, and a saturation signal generating device for generating a signal which saturates the voltage applying device. A rated voltage is applied to the motor by the saturation signal after the load is accelerated, and the saturation signal ceases at the beginning of decelerating the load. The motor is thereby caused to produce a rotating torque corresponding to the output of the signal converting device.

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Inazawa, Japan

Hiroshi Kamaike