| 摘要 |
PURPOSE:To permit a braking capability of the motor to be freely set by changing firing angles of thyristors constituting a rectifier circuit in which the motor is energized at the short-circuit of the rotor of the motor. CONSTITUTION:Since transistors 29, 26 and 25 are turned ON, when a revolving body rotated by a universal motor 12 reaches a specified position and a position detector 30 is turned ON, a transistor 20 is turned OFF and the thyristor 17 is turned ON. The rotor 13 of the motor 12 is by-passed by the turn-ON of the thyristor 17 and also, signal by a resistor 46 having set in a fixed speed is made ineffective by the transistor 29 being turned ON, and in return, a transistor 61 is turned ON, thyristors 2, 3 are turned on by phase angles capable of being set by a resistor 60, a current is passed through a field winding 14 to cause an induced current to be generated in the rotor 13 and a brake force in a direction opposite to the direction of rotation which has been continued so far acts on the motor 12 to make it stop. |
