Abstract: A mold core includes a forming pin having a hollow interior and an end wall. A passage, preferably in the form of a hollow tube, extends into the hollow interior of the forming pin and has an end sealingly secured at a position spaced from the end wall of the forming pin. A poppet valve is disposed on the end wall of the forming pin. The poppet valve is responsive to air pressure within the passage to open and permit flow of air through the end wall of the forming pin to assist stripping of molded articles from the mold core. The poppet valve includes a valve element having an outer end at the end face of the forming pin and an inner end adjacent to the end of the passage. A spring preferably biases the valve element to a closed position. The spring preferably comprises a coil spring captured in compression between the valve element and the forming pin.

Abstract: A mold core includes a forming pin having a hollow interior and an end wall. A passage, preferably in the form of a hollow tube, extends into the hollow interior of the forming pin and has an end sealingly secured at a position spaced from the end wall of the forming pin. A poppet valve is disposed on the end wall of the forming pin. The poppet valve is responsive to air pressure within the passage to open and permit flow of air through the end wall of the forming pin to assist stripping of molded articles from the mold core. The poppet valve includes a valve element having an outer end at the end face of the forming pin and an inner end adjacent to the end of the passage. A spring preferably biases the valve element to a closed position. The spring preferably comprises a coil spring captured in compression between the valve element and the forming pin.

Abstract: A mold core includes a forming pin having a hollow interior and an end wall. A passage, preferably in the form of a hollow tube, extends into the hollow interior of the forming pin and has an end sealingly secured at a position spaced from the end wall of the forming pin. A poppet valve is disposed on the end wall of the forming pin. The poppet valve is responsive to air pressure within the passage to open and permit flow of air through the end wall of the forming pin to assist stripping of molded articles from the mold core. The poppet valve includes a valve element having an outer end at the end face of the forming pin and an inner end adjacent to the end of the passage. A spring preferably biases the valve element to a closed position. The spring preferably comprises a coil spring captured in compression between the valve element and the forming pin.

Abstract: Apparatus for compression molding an annular closure shell having a base wall with a center opening and, in accordance with one aspect of the disclosure, includes male and female mold sections having associated male and female mold surfaces that generally oppose each other. The female mold section includes an opening in the female mold surface and a mold pin extending through the opening. The male and female mold surfaces cooperate to generally define the base wall of the annular closure shell and the mold pin cooperates with the male mold section to generally define the center opening of the annular closure shell. Closure of the male and female mold sections forms an annular mold cavity for receiving and compression molding a mold charge into the annular closure shell having the base wall with the center opening, which at least partially surrounds the mold pin.

Abstract: A mold core includes a forming pin having a hollow interior and an end wall. A passage, preferably in the form of a hollow tube, extends into the hollow interior of the forming pin and has an end sealingly secured at a position spaced from the end wall of the forming pin. A poppet valve is disposed on the end wall of the forming pin. The poppet valve is responsive to air pressure within the passage to open and permit flow of air through the end wall of the forming pin to assist stripping of molded articles from the mold core. The poppet valve includes a valve element having an outer end at the end face of the forming pin and an inner end adjacent to the end of the passage. A spring preferably biases the valve element to a closed position. The spring preferably comprises a coil spring captured in compression between the valve element and the forming pin.

Abstract: A mold core includes a forming pin having a hollow interior and an end wall. A passage, preferably in the form of a hollow tube, extends into the hollow interior of the forming pin and has an end sealingly secured at a position spaced from the end wall of the forming pin. A poppet valve is disposed on the end wall of the forming pin. The poppet valve is responsive to air pressure within the passage to open and permit flow of air through the end wall of the forming pin to assist stripping of molded articles from the mold core. The poppet valve includes a valve element having an outer end at the end face of the forming pin and an inner end adjacent to the end of the passage. A spring preferably biases the valve element to a closed position. The spring preferably comprises a coil spring captured in compression between the valve element and the forming pin.

Abstract: A compression molding machine, for compression molding a closure shell having a base wall with an opening and in accordance with one aspect of the disclosure, includes a male mold section and a female mold section having associated surfaces that oppose each other to form a cavity for compression molding the base wall of the closure shell. An annular bead on one of these surfaces cooperates with the opposing other surface to compression mold a disk connected to the base wall by a thin frangible web. The disk and the shell are stripped separately from the mold so that the shell emerges from the machine with the opening formed in the shell base wall by removal of the disk within the machine.