Abstract: A volume measurement and dosage device possesses a cylinder- piston- and valve-system (4). With this system, liquid can be drawn up and/or delivered in defined quantities. At least two channels (33, 36, 38) are provided in the valve-system, which can be connected with at least one opening (32) in the cylinder bottom (11). The piston (12) is displaceable within the cylinder (10) by means of an actuation device (3). The cylinder (10) is at the same time surrounded by a holding device (5, 40), in which it is mounted in bearings to rotate with the cylinder bottom (11) around an axis common to the longitudinal axis of the cylinder (Y) or parallel to it. The cylinder bottom (11), with at least two channel openings (29, 30, 31), rests with a sealed seating upon a valve element (28). Through rotation of the cylinder bottom (11), its opening (32) can alternately be aligned with the channel openings (29, 30, 31) of the valve element (28).

Abstract: The chamber (1) of the metering apparatus is defined by the inside wall surface of a cylinder (3), by a displaceable piston (4), and by a cylinder end portion (5) which is displaceable relative to the cylinder (3). Ducts (2a, 2b) are arranged in the cylinder end portion (5) in such a way that they can be selectively communicated with the chamber (1) or closed off by the end face (7) of the cylinder (3) In that way a part of the chamber wall acts directly as a shut-off member so that no residual volumes remain, which cannot be ejected by the piston (4).