PISTOL TIL GENTAGENDE AT AFGIVE NOEJAGTIGT AFMAALTE MAENGDER VAESKE FRA EN UNDER TRYK STAAENDE KILDE

摘要

A gun (10) is provided for repeatedly dispensing precisely metered quantities of liquid from a pressurized source. The gun includes a valve spool (28, 50) axially slidable within a valve chamber (21) and having at least first and second blocking members (28, 50) for blocking the inlet and outlet ports (25, 26) of the valve chamber. An actuating member (55) associated with the gun is responsive to a unidirectional force to impart relative axial sliding movement of the blocking members in the valve chamber. The relative axial sliding movement of the blocking members sequences the valve spool through a series of positions including the following: 1) a first position that blocks the outlet port (26) of the valve chamber (21), while permitting the flow of pressurized liquid into a metering chamber (22) of the gun, 2) a second position for stopping the flow of pressurized liquid by simultaneously blocking both the input and output ports (25, 26) of the valve chamber, and 3) a third position that blocks the inlet port (25) of the valve chamber while permitting communication between the liquid contained in the metering chamber (22) and a discharge nozzle (19) of the gun.