Dual mold clamping apparatus

Claim 1

An injection blow molding apparatus comprising a. means for injecting plastic material into at least one parison mold consisting of upper and lower mold halves and a mandrel centrally disposed therein, b. means for forming hollow articles from parisons formed in said parison molds consisting of at least one blow mold with upper and lower mold halves and means for introducing into said parison through said mandrel a fluid under pressure, c. one half of each of said injection and blow molds being mounted on co-planar stationary surfaces, the other halves of each of said injection and blow molds being mounted on respective mold mounting means movable in unison through attachment to a common member associated with a primary mold movement means into mold open and mold closed positions, d. means for transferring said mandrels with parisons molded thereon from said injection molds to said blow molds while said molds are in said mold open position, e. means for applying additional clamping pressure to said movable half of said injection mold in the mold closed position, said means including (1) additional clamping pressure resistance means independent of said primary mold movement means and common member associated therewith, and (2) selectively engageable means for applying and transmitting additional clamping pressure to said additional clamping pressure resistance means and to said movable injection mold half mounting means wherein said selectively engageable means comprises two mating circumferential interrupted spline members, one of which is reciprocably movable about their common axis to effect engagement and disengagement thereof, said members being freely movable past one another in their axial direction when disengaged and adapted to transmit forces in their axial direction when engaged, said movable injection mold half mounting means having a center line of pressure coincident with said axis of said spline members, wherein said movable injection mold half mounting means is attached to said common member through an extended portion about the periphery of which is disposed one of said interrupted spline members.