sensor for volumenbestimmung of liquid or gaseous media.

摘要

In a sensor (10) for determining the volume of a flowing medium, a piston (12) slides in a tube (11) on which a tapping electrode (15) and on either side of the latter an exciting electrode (13, 14) of length (1a?) are arranged. In the initial position of the piston (12) equal capacitances (C1? and C3?) are generated between the electrodes (13, 14) and the piston (12), the difference between which is then detected via the tapping electrode (15) with the aid of a bridge circuit. If the piston (12) is moved, a voltage (UA?) proportional to the volume is produced via the tapping electrode (15). The sensor is simple and cheap to make, and provides relatively accurate and linear readings.