Abstract: A method of stretch blow molding a plastic parison mounted to a parison engagement assembly into a container including stretching the parison by sliding the stretching rod therethrough and into the parison, connecting the cooling fluid inlet port to the source of cooling fluid to introduce the cooling fluid within the container through the cooling fluid outlet port, and heating the blow mold rod seal assembly to maintain at least a portion of the stretching rod above the preselected level, and to maintain portions of seals above the predetermined level.

Abstract: A cryogenic stretch blow molding apparatus including a stretching rod mounted to a blow mold rod seal assembly for sliding movement therethrough, into and longitudinally stretching a plastic parison, the stretching rod including a cooling fluid tube defining a cooling fluid inlet port for connection to a source of a cooling fluid and a cooling fluid outlet port to introduce the cooling fluid within the container, and a heater disposed in a cavity defined in the blow mold rod seal assembly for heating the blow mold rod seal assembly so that at least a portion of the stretching rod is maintained at a temperature above a preselected level to prevent accumulation thereon of ice sublimated from water vapor present in the blow air and portions of seals of the blow mold rod seal assembly are maintained at a temperature above a predetermined level to prevent seal failure.

Abstract: A blow molding apparatus configured to receive plastic parisons and output blow molded containers including a support frame and a parison conveyor attached to the support frame and having a plurality of parison supports and a drive mechanism for driving the parison supports in a stepped movement circuit, advancing the parison supports by a curvilinear distance corresponding to a curvilinear spacing between a preselected number of parison supports. A first parison transfer assembly is adapted to receive the preselected number of the parisons from the parison supports.

Abstract: Method and apparatus for forming stretch blow molded containers having uniform sidewall thickness from physical symmetric parisons. Parisons are heated non-uniformly by rotating at a non-uniform rate in a heating station. A sensor determines the angular orientation of the parisons emerging from the heating station. Each parison is angularly reoriented at a repositioning station prior to introduction into a stretch blow molding station having non-round interior surfaces, so that the temperature profile of each parison corresponds with differential expansion required to form the desired non-round container.

Abstract: An article repositioning apparatus for an injection stretch blow molding machine is disclosed for simultaneously molding a plurality of containers from plastic parisons. Between work stations, the apparatus repositions articles from a compact, evenly spaced first position to an extended, unevenly paired second position. After insertion of the articles into receivers slidably mounted on tracks, the receivers are moved by a servo motor to various separations by sliding movement along the tracks, the receivers attached to aligning ribs threadably engaged with ball screws. Simultaneously, the tracks are moved by a second servo motor to uneven paired separations by attachment to movable scissors having large and small scissor portions.

Abstract: A non-return valve for an injection molding machine is provided which includes a conventional tip member threaded into the end of a plasticating screw and carrying therewith an annular valve seat member. An annular check ring receives the tip member. Tang protuberances axially extend from the check ring to rotably engage the retainer end of the tip member. This causes the check ring to couple with the tip member during screw rotation to minimize valve wear while permitting the check ring to axially move relative to the tip member for effecting valve closure by pressure differentials in the normal manner. A ramp surface is provided on the tang protuberances which engages a drive surface on the retainer end of the tip/stud member upon reverse rotation of the screw through a predetermined rotational angle or for a set time to positively close the valve prior to injection.

Abstract: Biaxially oriented low cost polyolefin bottles of improved optical clarity, gloss, and strength, and useful for packaging materials such as liquid detergents, shampoos, pharmaceuticals and intravenous solutions, are prepared by stretch blow molding polypropylene homopolymer co-polymer and allomer parisons or preforms which are formed from low temperature melts at temperatures just above the melting points of the polymers and allomers, and are injected at constant rates against cold polished mold surfaces at relatively low pressures and at slow rates to avoid melt fractures. Melt temperatures of from 490.degree. to 700.degree. F. are preferred for polypropylene blow mold type polymers and allomers. Polished beryllium copper mold surfaces are desired for high luster gloss finishes. Mold temperatures of from 30.degree. to 80.degree. F. are preferred. Injection molding with a high compression ratio of 3 to 3.

Abstract: Parisons are presented at a pickup station related to a plurality of spaced molding stations and a spaced discharge station, so that a plurality of angularly spaced pickup and mold loading devices and a plurality of angularly spaced article transfer devices are operable on a cyclically oscillatable transfer mechanism for orienting the loading devices alternately in a parison pickup position at the pickup station and a mold loading position at the respective molding stations, and for orienting the article transfer devices alternately in an article stripping position at the molding stations and in a discharge position at the discharge station. In each cycle of operation, all of the devices are operated in coordination, and at least one parison is picked up at the pickup station, the at least one previously picked up parison is loaded into one of the molds, another mold is stripped of a molded article, and a previously stripped article is discharged at the discharge station.

Abstract: Parisons are presented at a pickup station related to a plurality of spaced molding stations and a spaced discharge station, so that a plurality of angularly spaced pickup and mold loading devices and a plurality of angularly spaced article transfer devices are operable on a cyclically oscillatable transfer mechanism for orienting the loading devices alternately in a parison pickup position at the pickup station and a mold loading position at the respective molding stations, and for orienting the article transfer devices alternately in an article stripping position at the molding stations and in a discharge position at the discharge station. In each cycle of operation, all of the devices are operated in coordination, and at least one parison is picked up at the pickup station, then at least one previously picked up parison is loaded into one of the molds, another mold is stripped of a molded article, and a previously stripped article is discharged at the discharge station.

Abstract: A tubular parison heating oven having a conveyor passing therethrough with parison holders rotatably mounted thereon for supporting the parisons in a vertical position. A toothed wheel is fixed to each parison holder for rotation therewith and a multiplicity of coil springs are vertically oriented and aligned adjacent the path of movement of the conveyor so as to engage the toothed wheel as the conveyor passes through the oven to cause rotation of the parison holders.

Abstract: A carriage, including a parison holding device, is mounted for movement between the oven and the mold to transfer a parison therebetween. A power actuated device such as a piston and cylinder unit has an actuated element connected to the carriage through a displacement multiplication arrangement so that the carriage moves a greater distance then the actuated element, thereby increasing the displacement of and reducing the acceleration forces on the carriage relative to the actuated element.