METHOD OF AND DEVICE FOR INJECTING AIR ATREAM EMPLOYED IN FORCING IN PROCESS THROUGH BLOWING INTO THE GOB PLACED IN A BLANK MOULD OF IN-LINE IS AUTOMATIC MACHINE FOR GLASS CONTAINER FORMING

摘要

A plunger (10) for intermittently delivery counterblow air to a gob of glass at a formable temperature in a blank mold of a I.S. glass container forming machine that is being operated on the blow and blow process. The plunger comprises a fixed annular member (12) with an enlarged recess (12a) at an inlet end and a valve seat (12d) at an upper end. The plunger also has a sliding valve member (14) within an annulus of the annular member (12), and the valve member (14) has a stem portion (14a) and an enlarged valve seat portion (14b) at a free end thereof. The plunger further has a collar (16) threadably and adjustably secured to the stem portion of the sliding valve member, and the collar, which is slidable within the recess of the annular member, has a plurality of air flow passages (16a) extending therethrough. Pressurized air is intermittently delivered to the recess of the annular member (12) through an inlet line (20), which has an on/off valve (22) therein. When the recess of the annular member (12) is pressurized, pressure therein will act on an underside of the collar to lift the collar and the valve member, jointly, with respect to the annular member, and thereby unseat the valve portion of the valve member from the seat of the annular member. This will permit pressurized air to flow from the recess of the annular member through the air flow passages in the collar, and then outwardly from the plunger through a gap between the valve portion of the valve member and the valve seat of the annular member. Upon the depressurization of the recess of the annular member, the valve member and the collar will return, by gravity, to a position where the valve portion of the valve member is seated against the valve seat of the annular member.