Patent ID: 6079226
Filing Date: 2000-06-27
Classification: C03B

Abstract:
A method of forming a gob of molten glass into a hollow article, said method comprising the steps of:delivering a gob of molten glass to an open mold cavity;closing said mold cavity;actuating a servomotor, said servomotor being connected to a leadscrew, said leadscrew being connected to a plunger, whereby said actuating of said servomotor causes rotation of said leadscrew which causes said plunger to advance in a forward linear direction from a first position until said plunger comes into contact with said gob at a second position;pressing said gob in said mold cavity with said plunger whereby forming said gob into a parison;moving said plunger in a rearward linear direction directly opposite said forward linear direction whereby said plunger breaks contact with said parison;stopping said plunger at a third position;continually sensing a linear position of said plunger throughout an entire length of travel of said plunger and controlling said servomotor to thereby control rotation of said leadscrew and advance of said plunger in response to a sensed linear position of said plunger; and,removing said parison from said mold cavity.