Dosing device for viscous material - has piston of dosing head provided with flushing liq. zone

摘要

Piston dosing head for delivering a measured quantity of a viscous material in a filling station includes a liquid zone adjoining the piston (15) for a flushing liquid. The flushing liquid zone has a variable holding capacity for the flushing liquid and is formed by the rear end of the piston and the wall of the bore and the end wall of the cylinder (14). The flushing liquid zone has a special inlet equipment (22) and outlet equipment (23) for admitting and discharging the flushing liquids. The inlet equipment (22) and the outlet equipment (23) are fitted each with a non return valve (24, 25) and the reciprocating movement of the piston (15) is controlling the flow of the flushing liquid through the flushing liquid zone. The viscous material is fed by a feeding equipment (11) in a cylinder (14) with the reciprocating piston (15) by which a predetermined quantity of the viscous material is measured.