Patent ID: 7147136

Claim:
A device for dispensing fluid material onto a substrate, comprising: a base body including a flow channel for receiving the fluid material, a movable valve body positioned in said flow channel, said valve body movable in a downstream direction into an open position to release a flow of the fluid material into said flow channel, and movable in an upstream direction into a closed position to interrupt the flow of the fluid material into said flow channel, a drive device configured to move said valve body between the open position and the closed position, a cylindrical chamber in said flow channel, said valve body including a piston movable within said cylindrical chamber, said piston configured for movement in at least the upstream direction after being sealed within said cylindrical chamber so that when said piston moves in a first direction within said cylindrical chamber, the fluid material is displaced from said flow channel and when said piston is moved in a second direction opposite to said first direction, the fluid material is drawn into said flow channel.