| 摘要 |
PURPOSE:To detect the position angle of the arm optically with non-contact, by providing the photo electric converter consisting of resistor and photo conductor three layer and the movable light means emitting light locally, and detecting the voltage produced between the two layers of the converter. CONSTITUTION:The beam light source 8 is fitted at one end of the sub-arm 7 fitted to the horizontal rotary axis 6 of the pick up arm 5, and the photo electric converter 11 having the resistor layer 1, photo conductor layer 2 and conductor layer 3 is provided at the position where the spot light from the light source 8 is collected, and the photo conductive layer 2 is constituted that it corresponds to the rotary locus of the spot light of the light source rotated unifiedly with the pick up arm 5. At the both ends of the resistor layer 1 of the converter 11, DC power supply 9 is connected and the DC voltmeter 10 is connected to respective one end of the resistor layer 1 and the conductive layer 3. Thus, the position angle of the pick up arm can optically be detected with non-contact. |
