| 摘要 |
PURPOSE:To detect accurately the slip rate of a belt by forming a rotation detection mark part at specific positions on the surfaces of a driving and a driven pulley between which the belt is extended, and detecting the passing of it. CONSTITUTION:Mark detectors 20 and 22 in this example emit measurement light to specific positions of rotation track surfaces of respective rotation detection mark parts 16 and 18 and photodetect reflected light generated when the rotation detection mark parts 16 and 18 pass by the position to output rotation passing detection pulses to FFs 24 and 26. Output signals from the FFs 24 and 26 function as gate pulses of NAND gates 28 and 30 and clock pulses from an oscillator 32 are also supplied to the NAND gates 28 and 30, which are opened when inputting H-level signals from the FFs 24 and 26 to output the clock pulses from the oscillator 32 to counters 34 and 36. Those counters count clock pulses corresponding to the numbers of revolutions of the driving and driven pulleys intermittently on every other turn, and a CPU46 calculates the quantity of a belt slip on the basis of the numbers of revolutions of the driving pulley 12 and driven pulley 14. |
