DRIVE DEVICE FOR MOTOR - MATSUSHITA ELECTRIC IND CO LTD

Title:

DRIVE DEVICE FOR MOTOR

Document Type and Number:

Japanese Patent JPS5950784

Kind Code:

A

Abstract:

PURPOSE:To prevent a motor from reversely rotating with a simple structure without using a reverse rotation detecting sensor or the like by detecting the presence or absence of a reference clock signal, and rapidly stopping the drive of a motor when the clock signal is defective. CONSTITUTION:When a reference clock signal is applied to a terminal A, it is detected at the point B by a diode 12 and a condenser 13. When the values of the condenser 13 and resistors 11, 14 are set so that the voltage at the point B becomes the voltage for turning ON a transistor 16, i.e., VBE or higher at the normal reference clock signal inputting time, the voltage at the point C becomes L level. If the clock signal is defective, the voltage at the point B decreases, the transistor 16 is turned OFF, and the voltage at the point C becomes H level. When the output level of the point C is used for the ON and OFF signal of a switch 4, it can prevent the motor 4 from reversely rotating when the clock signal is defective, thereby stopping the motor.

More Like This: