| 摘要 |
PURPOSE:To drive a nut by the weak force of a wavelength driving motor even after the nut has moved beyond a limit position, by completely inserting and connecting switches between the wavelength driving motor and a motor driving power source, and connecting a resistor to the switches in parallel. CONSTITUTION:One end of a sine bar 2 is linked and fixed to a diffraction grating 1, which is rotatably pivoted. The other end part of the sine bar 2 is slidably contacted with a flat surface of a nut 3. Switches 6 and 6', which are actuated by the nut 3, are provided at both limit positions in the wavelength measuring range of a wavelength feeding screw 4. When the nut 3 reaches the limit position, the power supply at the normal value to the driving motor 5 is stopped. Even though the switches 6 and 6' are turned OFF, however, a certain amount of power is continuously supplied to the driving motor 5 through a resistor 7. Therefore, the nut 3 can be driven even with a weak force. |
