Injection-blow molding machine having non-splitting injection and blow molds

An injection blow molding machine of the type in which a parison is formed by an injection molding process and the parison is formed into a container in a blowing process comprising:

• a non-splitting injection mold and a non-splitting blow mold mounted in stationary relationship within the machine with the mold axes located in parallel relationship with and equidistant from another axis through the machine, the mold cavities being formed around mold axes and each having a mouth opening the cavity at one axial end, the side wall of each mold cavity being shaped so that the transverse cross sections of the cavity perpendicular to the mold axis at each point along the mold axis are no larger than the other transverse cross sections lying between the individual cross sections and the mouth of the cavity whereby a parison or container can be withdrawn from the cavity without splitting the mold, the injection mold having an annular recess circumscribing the mouth of the mold cavity and the blow mold having an annular groove surrounding the mouth of the mold cavity;
• a parison pin mounted in the machine for rotation between positions in alignment with the mouths and axes of the mold cavities and for reciprocation in and out of the mold cavities whereby a parison may be transferred on the pin between the injection mold and the blow mold;
• and
• a set of split neckring segments also mounted adjacent and positioned coaxially about the parison pin for movement with the pin relative to the respective molds, the segments also being movable relative to the parison pin between a closed position in which the segments cooperate with the parison pin and define a neck portion of a parison and container narrower than the mouth of the blow mold and an opened position in which a blown container is released from the segments and parison pin, the segments also including projecting portions that form an annular ring mating with and fitting in the annular recess and groove of the injection and blow molds respectively when the parison pin is inserted in the molds, the annular ring having a contoured inner surface defining a shoulder of the blown container between the mouth of the blow mold cavity and the narrower neck portion of the container and being exposed in the blow mold cavity by the annular groove when the parison pin is inserted whereby the neckring segments engaging a blown container at a blow mold remove a blown container from the mold when a parison pin is reciprocated out of the mold cavity.

An injection blow molding machine for forming a container having a neck dimensionally smaller than the body of the container comprising:

• non-splitting injection and blow molds mounted within the machine defining mold cavities extending along corresponding mold axes and being generally disposed about the mold axes, the cavity of each mold having a mouth at an open end of the mold through which the molded article is removed from the mold and a bottom at the end of the cavity opposite the mouth with side walls of the cavity being disposed about the mold axis, the cavity cross sections perpendicular to the mold axis at each point between the mouth and the bottom of each cavity being at least as large as the other cross sections lying between the individual cross sections and the bottom of the cavity whereby the portion of a parison or container formed within a cavity can be withdrawn without splitting the mold;
• a parison pin mounted in the machine for movement between positions in alignment with the mouth and axes of each mold cavity and for reciprocation in and out of the mold cavities from the aligned positions;
• means mounted in the machine for moving the parison pin between the positions in alignment with the molds and for reciprocating the pin in and out of the molds whereby a parison may be transferred on the pin between the injection and the blow molds;
• and
• a set of split neckring segments positioned about the parison pin and mounted for movement with the pin relative to the injection and blow mold, the segments also being movable relative to the pin between a closed position in which the segments cooperate with the parison pin and define a neck portion of a container smaller than the mouth of the blow mold and an open position in which a blown container may be released from the segments and parison pin, the neckring segments also including portions that mate with the injection and blow molds and define the part of the blown container between the smaller neck and the mouth of the blow mold cavity whereby the neckring segments engaging a blown container at a blow mold remove a blown container from the mold when a parison pin is reciprocated out of the mold cavity.