Mitsubishi Denki Kabushiki Kaisha

Hideo Uchino

Masami Nomura

Hiroshi Kamaike

Masumi Kanbe

Takaaki Aoi

In an apparatus for automatic floor arrival at the time of service interruption in an A. C. elevator which is operated by an A. C. variable-voltage and variable-frequency control; when a slip frequency value during acceleration is at least a predetermined value, a burden raising mode is decided to switch running directions. Thus, in case of performing a rescue operation at the time of the service interruption, a load torque can be simply and reliably detected from the slip frequency value, and the elevator can be operated in a burden lowering direction. Another construction is such that slip frequency values during acceleration are integrated, and when the slip frequency integration value is at least a predetermined value, a burden raising mode is decided to switch the running directions. In the rescue operation at the time of the service interruption, whereby the possibility of an erroneous control ascribable to the influence of a ripple component included in the slip frequency during the acceleration can be reduced to the greatest extent.

Apparatus for automatic floor arrival at service interruption in A. C.

An emergency apparatus for elevator which converts a DC power into an AC power by an inverter device in an emergency state to feed the AC power to an AC traction motor and an AC motor for door-opening and closing which have different rated voltages so as to drive a cage of the elevator and to open and close a door of the cage comprises selectively feeding a power through said inverter device to either of said traction motor or said motor for door-opening and closing, in an emergency state.

Emergency apparatus for 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.

Growing community of inventors

Inazawa, Japan

Hideo Uchino