Abstract: A technique for internally cooling a blow molded article with a coolant comprising a mixture of subzero temperature dry air and water. A pressure swing dessicant bed type dryer and chiller are used to supply the dry air having a dew point of the order of -60.degree. F and a temperature ranging from -30.degree. to -50.degree. F for introduction into the blow molded article.

Abstract: An improved shell mold and method are provided for thermal conditioning a thermoplastic parison prior to blow molding the parison into a hollow container and especially a biaxially oriented container. The mold has an inner shell and an outer shell defining a passageway therebetween for a circulated heat transfer fluid. Heat transfer between the fluid and the parison is controlled to adjust the thermal history at different locations of the parison as it will be required by the mode of stretching and the blow out ratio at the different locations.

Abstract: An integral blow-moulding machine heats and extrudes plastic parisons having variable wall thicknesses directly between the opened half moulds of a continuously rotating ferris wheel type blow moulder. The parisons are severed and thereupon grasped by hydraulically closed half moulds. An electric discharge device is adapted to softening part or all of the parison during extrusion. Air injection is performed using a conventional extensible injection needle. After blowing the half moulds are hydraulically opened while the blown object is held by pneumatic grippers. During the extraction procedure the flash is removed from top and bottom of the blow moulded object by hydraulically operated means.

Abstract: A method are disclosed for heating thermoplastic parisons to a substantially uniform temperature across their wall thickness prior to a blow molding operation. In the method, the parisons are rotated about their longitudinal axes while being conveyed adjacent a thermal conditioning means, which includes vertically spaced radiant heating elements and a gaseous cooling source. The heating elements radiate infra-red rays having a wave length to penetrate and heat the full thickness of the parison wall; whereas the gaseous cooling source directs a stream of air onto the surface of the parison facing the heating elements to prevent the parison surface from being overheated. Additionally, each of the heating elements may be individually regulated so that the parisons can be differentially heated along their axes to control the wall thickness of the final blown articles.

Abstract: A blow mold structure for the blowing of containers, bottles or the like rein a coolant fluid is circulated through the mold. The blow mold includes a pair of openable and closable mold blocks, each carrying a mold insert. The changeable inserts cooperably define the mold cavity, and coolant fluid is circulated between each insert and the adjacent mold block to cool the cavity-defining inserts. A series of grooves is formed in the exterior surface of the mold insert, the insert is sealed to its mold block and coolant fluid is introduced into and removed from the grooves through supply passages in the mold block. A chamfered abutment at one end of each insert and a mounting flange at the other end insures quick changing of inserts while maintaining structural rigidity during use.

Abstract: Machine for injecting and blowing a plastics material into hollow bodies. It comprises a rotary polygonal-sided turret which carries on each side a set of support members for the plastics material which are made to pass step-by-step to an injection station for injection of a blank and a blowing station for blowing the material into a hollow body in passing through intermediate stations including a transfer station. A rotatable oven structure having sockets rotatable step-by-step about an axis of the oven structure is located adjacent the transfer station for transferring the sets from the turret to the oven structure and, after a complete rotation about the oven structure axis, transferring the sets from the oven structure to the turret. Each turret side and each socket of the oven structure receives a respective one of the sets which is fixed to the turret or oven structure in a removable manner to allow the mentioned transfer.

Abstract: An open end parison preform is heated to molding temperature preparatory to transfer to a molding station. The thus heated parison is grasped by a pair of opposed picker fingers and transferred into position over a neck forming plug. The relative temperature of the opposed picker fingers is controlled which effects the alignment of the bottom end of the parison over the plug.

Abstract: Parisons are injection molded using a cooled cavity and a relatively hot core pin to prevent the formation of residual internal stress in or near the inner surface of the parison. The parison is promptly transferred while still hot from the injection mold to a temperature conditioning station to provide a desired temperature distribution and the temperature conditioned parison is highly molecularly biaxially oriented as it is blow molded.

Abstract: Parisons for use in making blow molded highly molecularly oriented plastic bottles are injection molded using a cooled cavity and a relatively hot core pin to prevent the formation of residual internal stress in or near the surface of the parison. The pin is maintained at a temperature above the glass transition temperature of the resin to reduce the formation of cracks when the parison is subsequently blow molded in the orientation temperature range.

Abstract: Apparatus for temperature-conditioning workpieces comprises a series of bar assemblies for supporting a number of elongated molded parts in side-by-side relationship, heat transfer assemblies including horizontally spaced panels extending along a chamber, means for conveying the parts supported in the bar assemblies through the chamber between the panels and rotating means operatively interconnected with the conveying means and bar assemblies for turning the parts. Infeed means sequentially release loaded bar assemblies at regular intervals to the chamber while metering means preferably driven through downstream equipment continuously release bar assemblies to the discharge end of the chamber. Reciprocable gate means allow temperature-conditioned parts to drop out of the bar assemblies to collection equipment. Process improvements include a.) varying parts conditioning time by varying the number of bar assemblies in the fixed length chamber; b.

Abstract: A system and method for forming elongated and involute thermoplastic articles is disclosed. Means are provided for controllably heating a sheet of thermoplastic material to form preselected temperature gradients throughout the sheet of thermoplastic material. Means are further provided for planarly supporting the heated sheet of thermoplastic material allowing for transverse motion of the heated sheet of thermoplastic material at the center thereof and further allowing for controlled slippage of the heated sheet of thermoplastic material toward said center thereof relative to the planar support means. Means are also provided for transversely forming a heated sheet of thermoplastic material into the shape of an elongated or involute plastic article. A plug is used to extend the heated sheet of thermoplastic material into an elongated conical shaped piece.

Abstract: A machine for blow molding articles, particularly bottles wherein a central, horizontal shaft carries a plurality of radial arms positionable at an equivalent number of work stations arranged in a common vertical plane. The work stations are grouped around the central shaft and are at varying distances from the shaft, and the arms are extensible to reach the stations furthest spaced from the shaft. Fixed actuating means are located adjacent the remote stations and the extensible arms are coupled to the actuating means located at these remote stations. In this way, the extensible actuating means is provided only where needed, the mass and complexity of the rotary arms is reduced and a simple, efficient structure is obtained. The method of the present invention includes the rotation of the shaft in stepwise fashion to align the arms in succession with the work stations and coupling the arm to the fixed actuating means for extension and retraction of the arms at the remote work stations.

Abstract: This invention relates to blow molding apparatus for making plastic articles. It circulates cooling fluid through core rods for cooling blown articles from the inside, preferably with the blown article on the outside of a balloon that is permanently connected with the core rod. The connection of the balloon to the core rod is constructed so that there is no axial pull on the balloon during stripping of the blown article from the core rod and balloon. The invention provides constructions for admitting air between the balloon and a blown parison to break the vacuum when the balloon is to be collapsed. Fluid is also circulated over the outside of the blown parison to cool it, and this can be done in a perforated shroud that serves as a blowing mold, particularly for flexible wall containers.

Abstract: A molecularly oriented article having a tubular sidewall is blow-molded from a thermoplastic parison which is heat-treated prior to blowing to provide the parison sidewall with a temperature gradient wherein the temperature of the inside of the sidewall is greater than that of the outside, both of said temperatures being within the orientation temperature range of the thermoplastic. The temperature gradient results in the sidewall of the article having a different and more uniform circumferential orientation release stress distribution radially across the sidewall than would be obtained if the parison were blown isothermally.

Abstract: A filled, fluid barrier resistant plastic container is obtained wherein the container is exposed to a temperature in excess of 175.degree. F., as for example being filled with a material maintained at said elevated temperature. A multilayered, hollow plastic container is provided having outer and inner portions of thermoplastic materials resistant to temperatures in excess of 175.degree. F., and a barrier layer of thermoplastic material between the outer and inner portions. The container may be filled with a material at a temperature in excess of 175.degree. F. but below the temperature of resistance of the inner and outer layers whereby the barrier layer softens or melts, and the filled container is cooled to ambient temperature whereby the barrier layer reforms in place to provide the filled, barrier resistant container of the present invention.

Abstract: A method of making a concave bottom on a blown thermoplastic container. A blowable pre-form is initially expanded against a composite mold surface defined by the end faces of a plurality of concentric tubes surrounding a central actuating rod. The rod and the tubes are initially telescopically positioned to define a composite concave surface, so that a first convex bottom is blown. Subsequently, the rod and tubes are actuated telescopically to progressively invert the convex bottom to a concave shape. The end faces of the tubes may be grooved to define reinforcing ribs in the concave bottom wall, if desired.

Abstract: Molecularly oriented containers are formed from molded preforms made of an amorphous thermoplastic resin and having a finished neck tubular portion and a body portion which method includes subjecting the preform body to a thermoforming orienting step while at a temperature at which substantial molecular orientation occurs, said temperature being arrived at by first overheating the outside of said preform body using external heating means to an average outside temperature greater than the substantial molecular orientation temperature range thereby creating a temperature gradient across the thickness of said preform body and then cooling said headed preform body until the average outside temperature is within said,substantial molecular orientation temperature range and the entire preform body is at a temperature within said substantial molecular orientation temperature range and whereas said temperature gradient is significantly reduced.