Device for delivering a predetermined volume of a pasty fluid

摘要

A piston-drive device for delivering a predetermined small volume from a nozzle as a function of an electrical signal without a time delay is permitted by the slow rotation of a ball-screw shaft, the rotation being reduced by a differential gear system. A screw bush mounted on a ball-screw shaft moves a piston with very low speed, so that the exact delivery of a predetermined volume of a pasty fluid is possible. The vertical movement of the nozzle is compensated by a vertical movement of the piston-drive device in such a way that the relative position of the piston with respect to the nozzle remains unaltered.