Mitsubishi Denki Kabushiki Kaisha

Nobuo Anzai

Eiki Watanabe

Hiroyuki Ikejima

Tsuyoshi Satoh

Hiroshi Kamaike

Takao Kato

An apparatus for controlling an A-C powered elevator wherein: when a frequency instruction value lies within a predetermined frequency range, an inverter in the apparatus produces an A-C electric power having a frequency which lies outside said predetermined frequency range, so that the frequency of the electrical power supplied from said inverter to the motor driving an elevator cage will be out of the resonant frequency range of the mechanical system of the elevator. Namely, an inverter is connected to a D-C power supply, the inverter is controlled by a voltage instruction value and a frequency instruction value, a D-C electric power is converted into the A-C electric power having a variable voltage and a variable frequency by said inverter, and an A-C electric motor is powered by the thus converted A-C electric power to drive an elevator cage, wherein a frequency conversion computer is provided which, when said frequency instruction value lies within a predetermined frequency range, sends to said inverter a frequency instruction value which lies outside said frequency range.

Apparatus for controlling an A-C powered elevator

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.

Control system for D.C. electric motor

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.

Deceleration controlling apparatus for elevator

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.

Elevator control apparatus

A position sensor disposed on an elevator car has a first rotatable shaft connected to a secondary winding of a transformer or a switch actuating member, and a second rotatable shaft coaxial with the first shaft and connected to a primary transformer winding or to a switch position changing member. A first roller engages a rod-shaped cam mounted at an angle to a guide rail for the car toward the end of the path of travel of the car to rotate the first shaft in a direction to decrease the voltage across the secondary winding or successively actuate the switches. If the car moves horizontally, the first shaft is rotated to change the voltage and a second roller engaging the rail rotates a second shaft to compensate for this change in voltage.

Position sensor device for elevator car

A speed control apparatus for AC elevator comprises a multi-speed AC motor having two or more windings and a power running circuit for starting the motor by a low speed winding in the acceleration and switching to a high speed winding after accelerating it near the synchronous speed.

Speed control apparatus for AC elevator

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.

Elevator control system

The disclosed brake includes a brake wheel directly connected to an electric motor for an elevator car, and a pair of opposite brake shoes resiliently engaging the brake wheel through respective brake linings applied to the shoes and responsive to the energization of an electromagnet to permit the rotation of the motor. Each shoe is provided on that side remote from the brake lining with a heater for continuously heating the lining to prevent it from becoming wet.

Brake for elevator

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

Nobuo Anzai