U.S. Pat. No. 7,255,824 to CERNY et al., published on Aug. 14, 2007 discloses an apparatus for molding a plastic closure that includes a male mold assembly including a forming pin and an outer pin sleeve which cooperate with a female mold for defining a mold cavity. To facilitate mechanical stripping of a molded closure from the forming pin, pressurized air is introduced into the molded closure through at least one air passageway which extends axially between the forming pin and pin sleeve. By outwardly expanding and forming the plastic closure during ejection from the forming pin, forces to which the closure is subjected during ejection are significantly reduced, thereby desirably reducing the amount of cooling of the closure that is required during the molding cycle prior to ejection. Significantly increased operating speeds for the compression molding apparatus can thus be achieved.
USPTO Backgrounds
USPTO Backgrounds