| 摘要 |
PURPOSE:To prevent the measuring accuracy of the number of revolutions of a ring gear from being effected due to accuracy of the pitch of teeth supplied to the ring gear by correcting a data outputted from a pulse count means based on a stored pitch data. CONSTITUTION:A tooth formed to the ring gear 1 is detected by a pickup 2, a pulse signal is waveform-shaped by a waveform shaping circuit 3 and outputted to a clock pulse counter circuit 13. When a drive command signal is outputted from a control circuit 15 by a signal outputted to a clock pulse generating circuit 11, a pulse is outputted respectively from the clock pulse counter circuit 13. A correction circuit 14 uses a command signal from the control circuit 15 to obtain a pitch error epsiloni data read sequentially from a pitch error memory circuit 12 and a true measurement qi at each pitch. When a true measurement at each pitch is outputted from the correction circuit 14, a reciprocal of the measurement being a value inversely proportional to the number of revolutions of the ring gear 1 is displayed on a digital number of revolution display device 6. |
