DEVICE AND METHOD OF MEASURING DIAMETER OF SHAFT

PROBLEM TO BE SOLVED: To reduce the cost of a device, and to quickly measure while performing accurate diameter measurement for a small diameter part and the diameter measurement for a large diameter part which does not require the accuracy as high as for the small diameter part with the same device. SOLUTION: A device is provided with a support base 30 for supporting a shaft part 20, a contact displacement meter 40 having a contact shaft 41 capable of being extended and shrunken along the outer peripheral surface of the shaft part 20, a scanning device 50 for scanning the contact displacement meter 40 in a direction crossing the extending direction of the contact shaft 41, a moving device 60 for moving the contact displacement meter 40 in the direction for extending the contact displacement meter 40, and an excursion device for making the contact displacement meter 40 and the scanning device 50 travel along the rotary shaft direction. Each pair of the contact displacement meters 40, the scanning devices 50 and the moving devices 60 are symmetrically arranged in both sides of the rotary shaft of the shaft part 20, and stopper mechanism 130, 140 for regulating the movement of the contact displacement meter 40 by the moving device 60 are provided.