Ball valve for adhesive dispensing gun - has recess wider than seating ring, leaving clearance permitting travel of ring to prevent clogging

摘要

The dispensing gun for a paste product such as an adhesive, which is pushed through the barrel in solid stick form, has a dispensing nozzle (5) incorporating a ball valve. The discharge hole (19) is preceded by a larger diameter chamber (10) containing a spring (8) which holds the ball (9) against a seating ring (13). This ring is retained inside a groove (18) having a width which is greater than the ball diameter. The ring leaves a clearance (15) inside the groove, towards the discharge end, when the valve is closed. When pressure moves the ball away from the ring so as to open the valve, the sealing ring also moves axially. This movement prevents clogging of the seating.