| 摘要 |
<p>PURPOSE:To permit the speed of a motor driving a precision moving body to be controlled according to the desired location of the moving body by varying an oscillating pulse frequency with the change of the electric-resistance constant of a CR oscillation circuit containing a variable resistor as a resistance element. CONSTITUTION:With the difference between desired and present locations of the object-mounting table 10 of a microscope or the like computed in a control unit 26, the unit 26 actuates proper diode-elements in a light-emitting diode array 18 to light corresponding to the size of the difference. Since the variable resistance of an optical potentiometer 16 inceases as the difference between the desired and present locations decreases, the resistance of the potentiometer 16 gradually increases as the table approaches the desired location, and the gradual increse of the electric-resistance constant of a CR oscillator 22 causes the oscillation pulse number to gradually decrease, so that the speed of a pulse motor 28 is decelerated. When the table reaches the desired location, oscillation pulses below a fixed frequency are output from the CR oscillator 22, in order to stop the motor 28.</p> |
