| 摘要 |
PURPOSE:To detect the direction and quantity of a screw shaft moved in a high resolution by setting up a member to be detected, to which a large number of slits are formed at regular pitches, to an outer circumferential surface in a rotor while mounting a photodetector consisting of a light-receiving element and a light-emitting element at every one third pitch. CONSTITUTION:A disk 8 in which a large number of the slits 8a through which beams irradiated from the photodetectors 9-11 are passed are formed at every pitch 3l1 of treble as large as the fitting pitches l1 of the photodetectors 9-11 is fixed at the shaft end of the rotor 1 of a motor. The electric signals of the photodetectors 9-11 are converted into digital signals by an amplifying circuit and a conversion circuit. A control circuit arithmetically operates the direction and quantity of the screw shaft, which is screwed to the rotor, moved on the basis of these digital signals, and outputs moving-direction indicating signals and moving-quantity indicating signals. |
