Electrodynamic braking device for universal motor, has control electronic unit simulating brake operation and motor operation, switch conductively switched, and other switch conductively switched with predetermined time delay

摘要

The device has a switching unit switching from a motor operation to a brake operation, where a field winding (3) of a universal motor is fed from a grid by two switches (1, 1') during brake operation. An armature (2) of the motor is short-circuited by the switches. A control electronic unit (5) simulates the brake operation and the motor operation during the brake operation with each half cycle of main voltage for a short time. One of the switches is conductively switched, and the other switch is conductively switched with a predetermined time delay. An independent claim is also included for a method for braking a universal motor.