Dosierung von Waschmittelpasten

摘要

The invention relates to a dosing apparatus for pastelike substances and mixtures thereof with a solvent by means of an injector (2), comprising an integrated shut-off device. The apparatus contains a detection device which detects the amount of paste according to conductimetry. The shut-off device is a dual piston valve (5, 6) closing an opening between the paste supply tube (7) and an injector suction chamber (4) as well as an opening between the solvent supply tube (8) and an injector pre-chamber (3). The invention also relates to a method for dosing pastelike substances and the mixtures thereof with a solvent by means of such a device. By opening a shut-off device (9) in a supply tube (8) for a pressurized solvent, a dual piston valve (5, 6) moves against an opposing force. This releases a connection between a paste supply tube (7) and an injection suction chamber (4), followed by a connection between the solvent supply tube (8) and the injector pre-chamber (3). The paste is suctioned by an injector (2) operating according to the hydraulic pump principle and mixed with release solvent. The mixture is injected into a measuring section (13) wherein a conductimetry device measures the amount of paste dissolved in the mixture. The shut-off device (9) is closed when the required dose of paste is obtained, whereupon the circuit which was previously in open position is shifted in reverse order to closed position.