Instruments to measure differential diameters - measure corresponding diameters of wheel rims of two wheels on the same axle

摘要

The two wheels are pref produced by turning. A friction wheel runs on each measured diameter, with one of the friction wheels connected to an angle step controller, in turn connected to a digital counter. An operating element for a switching pulse generator is mounted on one of the wheels. This generator is connected to the digital counter and switches it on and off. Each friction wheel drives a markable disc, opposite which a marking device is provided, stationary relative to the disc. Switching pulse generator delivers a pulse to the two marking devices for the discs marking at the beginning and end of each measurement cycle.