Abstract: Mould assembly for foam moulding of plastic materials, which comprises stationary and movable dies and an auxiliary die plate device between the stationary and movable dies. A gas passage is formed for introducing pressurized inert gas into the mould cavity. The auxiliary die device comprises separated inner and outer auxiliary dies both being spring biased toward the stationary die. O-ring seals are disposed between the opposite surfaces of the outer auxiliary die and the stationary and movable dies.

Abstract: Disclosed is an apparatus and process for the molding of hollow articles such as full length Foley catheters. The apparatus preferably comprises a mold with two lumen forming wires longitudinally disposed therein. A set of two receiving wires are spaced distally from the distal ends of the lumen forming wires and are longitudinally aligned therewith. A first follower is slidably disposed about the lumen forming wires in close abutment with the wires and inside wall of the mold. The first follower is preferably disposed toward the proximal end of the mold and preferably at least two other followers are provided spaced distally of the first follower. One of the other followers preferably bridges the space between the lumen forming wires and receiving wires. Sets of gates are preferably provided along the length of the mold in fluid communication with a source of molding material.

Abstract: A mold is described for the molding of substantially isotropic isocyanate-based polymer foam buns. The mold is a box mold which has sidewalls of which at least one pair disposed in parallel relationship is adapted to move outwardly when subjected to pressure exerted by the expanding foam during the molding operation. The outward movement of the sidewalls is controlled by stops provided on the periphery of the mold floor, said sidewalls being free to slide over the surface of the floor. The lid of the mold is supported in sliding engagement with the upper edges of the sidewalls. The mold and the process of fabricating foam buns therewith is particularly suitable for use in situations (e.g. operation in the field) in which it is not possible or practicable to employ continuous bunstock machines. The mold is relatively inexpensive and readily dismantled for transportation to a fabrication site.

Abstract: Disclosed is a method of casting silicon metal. Silicon metal expands upon solidification. According to the disclosed method a void volume of from 1 to 10 percent of the silicon metal, basis molten silicon metal, is established within the molten silicon metal. The void volume is capable of being decreased in volume upon the solidification of the silicon metal. In this way, the increase in volume of the silicon metal upon solidification is offset.

Abstract: A process and apparatus particularly suited for casting ophthalmic lenses from a liquid monomer such as "Cr-39". The liquid monomer and a catalyst are metered into a plastic lower mold member. A plastic upper mold member is supported by the upper surface of the liquid and by a suspension arrangement which includes a spacer ring and a plurality of ears extending from the upper mold member. The upper mold member is controllably drawn downwardly as the liquid plastic solidifies. Optical surfaces are obtained without polishing or other finishing.

Abstract: In a method for the preparation of crosslinked polyolefin foams by charging a polyolefin or its blend with other thermoplastic resins containing a crosslinking agent, foaming agent and if necessary a filler into the heated mold having a changeable cavity and, after decomposition of the crosslinking and foaming agents, retracting the moving-plate of the mold by a definite distance to increase the cavity and at the same time cooling the mold, an improvement for the preparation of the crosslinked polyolefin foams having excellent appearance and dimensional stability, comprising using a mold of which the moving-plate is constructed with a body and a sliding-piece, the body holding the piece slidably whereby the sliding-piece is left behind owing to sliding between the two even on rapid retraction of the body and then retracts at the rate corresponding to the foaming pressure of the resin, in other words, at a self-controllable rate and the mold for the preparation thereof.

Abstract: A molding apparatus is described having a body portion with a mold cavity therein and a core means within said cavity having a core follower thereon which is designed to move along the core during the molding operation. Utilization of the core follower permits rapid and accurate formation of multiple lumen tubes, particularly those having arcuate shapes.

Abstract: An assembly of loaf molds defining a magazine, including a pair of vertically extending and horizontally spaced forks and a plurality of horizontally extending and vertically spaced molds secured near opposite ends to the forks. Wheels are mounted on the forks to coact with support rails along which the magazine may be driven. Driving pins are also mounted on the forks to coact with a suitable driving mechanism.

Abstract: The invention relates to a method of forming a moulded product comprising a reinforcement encapsulated in a plastics material. The reinforcement is supported in a mould cavity spaced from the surfaces of said mould cavity by support pins which are retractable into the mould surfaces. During an initial part of the moulding operation some of the plastics moulding material enters one or more reservoirs each formed in or around one of the support pins, the reservoirs opening into the mould cavity and extending inwardly of the mould surface, and on retraction of each pin, a piston, working in each reservoir, forces the moulding material out of the reservoir into the vicinity of the part of the mould cavity previously occupied by the pin.

Abstract: A mold for processing a food material, including a plug and ratchet take-up mechanism for accommodating expansion and contraction of the food product. The plug is provided with ratchet arms having ratchet teeth and the take-up mechanism includes spring biased pins or pawls coacting with the ratchet teeth.

Abstract: A pressure die-casting block, wherein two block halves are assembled together along a plane defining a parting plane of the blocks and provide an internal cavity for performing a die-casting operation. The block is provided with a device for attenuating pressure forces which arise during the casting operation, the device being disposed in one of the block halves and acting in the parting plane of the block.