Abstract: An applicator head for the metered release of flowing media, particularly hot-melt glues, cold glue paste, lubricants, paints, or similar substances, comprises a housing within which there is disposed a pivoting rocker having two oppositely disposed rocker arms which are operatively associated with two valve mechanisms. Two stacks of piezoelectric elements are disposed upon opposite sides of a rocker axis such that when a particular one of the stacks of piezoelectric elements is energized or activated, the rocker is pivoted about the rocker axis whereby one of the valves is opened while the other valve is simultaneously closed. In accordance with one embodiment of the invention, one of the valves is an applicator or dispensing valve and the other one of the valves is a closing or recirculation valve operatively connected to a recirculation system. In accordance with a second embodiment of the invention, both valves are applicator or dispensing valves.

Abstract: The present invention comprises an applicator head for the dosed dispensation of fluid mediums wherein a valve member and a valve drive are arranged within a casing. The valve drive comprises at least one piezoelectric element connected with a voltage supply and comprising several parallel, juxtaposed piezoelectric stacks which are flexibly mounted. The present invention provides a piezoelectrically driven applicator head which is simple and economical to manufacture, and which is usable not only in the low-temperature range but also in the high-temperature range.