| 摘要 |
PURPOSE:To stop a spindle motor rapidly by controlling a discriminating circuit and an impressing circuit to activate alternately time divisionally by the controlling circuit until the discriminating circuit discriminates the motor is not rotating in a positive direction. CONSTITUTION:At every time when the output signal (e) of a pulse generating circuit 3 becomes '1', the brake voltage is impressed on the spindle motor 1 to brake it. And, at every time when the signal (e) becomes '0', whether or not the motor 1 is rotating in the positive direction is discriminated by whether the output signal (d) of a comparator 2 is '1' or not. If the output (e) of the generating circuit 3 becomes '0', the output signal (f) of a NAND gate 4 becomes '1' and the output signal (g) of an FF 5 also becomes '1'. By such a way, a switching circuit 8 connects to a connection point B, and the voltage to be impressed to the motor 1 is made OV. And when the motor revolves inversely, the output signal (g) of an FF 5 is maintained in '1', and a circuit 8 also maintains the connecting state to the point B. Therefore, the motor becomes in an non-excitened status to be stopped quickly. |
