Coding potentiometer for position control of machine tool - has digital voltmeter measuring potentiometer voltage output using wipers acting on spaced contacts to calculate shaft rotation

摘要

The power supply circuit (13) provides a filtered dc voltage from the mains for a coding potentiometers (2,5) through current limiters (14,19). The wiper contact (8) on one potentiometer (2) has a make before break action on the winding contacts. This wiper is connected to the count up and count down electromagnets in parallel in an electromechanical counter (15). The electromagnet outputs are connected through diodes (16,17) to a capacitor (18) to provide rapid charge or discharge to operate the respective counter. A second potentiometer (5) has its wiper coupled to a shaft. This wiper makes contact with a single winding contact to provide positional precision, and is connected to a digital voltmeter (21) with a blanking control system (22). The shaft rotation is determined from the Voltage and number of teeth on the potentiometer winding.