Back to results
US 4,543,515 AGranted
Motor controlling switch device
AssigneeKabushiki Kaisha Tokai Rika Denki Seisakusho
InventorMasaru Suzuki
Life of this patent
Estimating the term…
Abstract
A motor controlling switch device in which, when the motor is stopped in locking manner, an operating member for operating the switch and for applying current to the motor is returned from an operating position to an original position. The magnetic force of a voltage coil holding the operating member at the operating position is cancelled out by a magnetic force of a current coil which is induced therein by the locking current of the motor.
Claims8
A switch device for controlling an electric motor comprising:
- an operating member for taking an original position and an operating position for enabling a supply voltage to be applied to the motor;
- means for applying a restoring force to said operating member when said operating member is in said operating position to urge said operating member to move from said operating position to said original position;
- and
- an electromagnetic device for receiving said supply voltage and for producing a first magnetic force stronger than said restoring force to attract and to hold said operating member in said operating position, said electromagnetic device also for receiving current flowing in said motor and for producing a second magnetic force equal in strength to said first magnetic force in response to a predetermined condition of the motor, said second magnetic force controlling said first magnetic force to enable said restoring force to restore said operating member to said original position responsive to the occurrence of the predetermined condition of the motor.
1 more element
Dependencies are inferred from the claim text.