Abstract: Apparatus for injection-moulding articles of plastics material onto a preformed web inserted into the mould, the web is held under substantially constant tension during the closing of the mould, between a pair of clamps, the proximal clamp being fixed relative to the mould and the distal clamp free but bearing a load to furnish the desired tension in the web. The load may be imposed by a weight attached to the distal clamp, conveniently by means of an electromagnet.

Abstract: The invention is concerned with a process for forming a unitary seal comprising a support section formed of a high modulus, i.e. rigid high impact strength plastic and a sealing section formed of an elastomeric material, the support and sealing section being directly bonded together without the use of an adhesive therebetween to form the unitary seal. The process comprises contacting a surface portion of the support section directly with a surface portion of the sealing section, under sufficient pressure to assure a pressed contact therebetween, with the sections at a temperature of 50.degree. C.-400.degree. C. for a time sufficient to cause bonding between the contacting surface portions to form the unitary seal.

Abstract: A method of enveloping an electrical component in a thermoplastic material is provided. The facing surfaces of two parallel spaced strips of a closed-cell cellular thermoplastic material are heated to a temperature above the softening or melting temperature of such thermoplastic material while maintaining the temperature of the remainder of each strip below such softening or melting temperature. In this condition the two strips and the electrical component are introduced into a mould with the component between the heated surfaces; and the mould is closed about the strips to plastically deform the same and to encase the component therebetween.

Abstract: A method of producing an endless reinforced toothed belt of synthetic plastics material, the circumferential length of which in the untensioned condition has a predetermined minus tolerance in relation to an operationally tensioned intended circumference having the exact tooth pitch. The steps include placing on a molding wheel and a tensioning wheel a helically wound wire coil with fixed wire ends, the molding wheel and the tensioning wheel having an interaxial distance at which the wire coil has the minus tolerance in relation to the intended circumference. Then the wound wire coil is tensioned with elastic stretching of the wire turns and is enlarged to the intended circumference by increasing the interaxial distance to the intended distance.

Abstract: Apparatus for manufacturing an at least partly tubular body, provided with an elastic sealing ring accomodated in an internal groove in said member. In a moulding cavity of a mould first the tubular member is formed of plastic synthetic material, thereafter an annular cavity is arranged in the mould adjacent the outer surface of the body and subsequently a pressurized thermoplastic deformable material is brought against the inner surface of said body which material is an elastomer at the temperature of its normal use. Thereby the body is forced into the annular cavity and is simultaneously forming the internal groove, which is filled with elastomeric material.

Abstract: A continuous flexible metal band surrounding a molding wheel and rotating therewith engages the wheel through an arc less than 180.degree., e.g. 110.degree., and is maintained with a substantial inward radius of curvature throughout its entire length. This permits the employment of bands with cavities therein and having thicknesses several times greater than 0.001 times the diameter of the molding wheel without fatigue and failure of the band.

Abstract: A bone replacement, for example a portion of a hip joint, a bone junction plate, or the like, includes a core element of a fiber-reinforced thermosetting material with a surface element made of a biologically compatible material, typically polyethylene, completely surrounding the core element. The outside surface element is internally interlocked with the core element, by being molded in one heat treatment operation which simultaneously cures the thermosetting material while molding the outside biologically compatible surface element thereto and interlocking and integrating the two elements into one unitary structure. Preferably, the fiber reinforcement is formed as fibers, woven mats, felted mats, or the like, and the surface element may, likewise, include a reinforcement beneath the surface actually in contact with the human body.

Abstract: A mold comprises a base, a split die and a plunger. The base has longitudinal shoulders with resilient elements, and sloping surfaces which form an upwardly flaring nest adapted to accommodate a vertically movable die. The side walls of the die have their sloping surfaces in contact with the sloping surfaces of the longitudinal shoulders and, together with the die end walls, are placed around the die bottom. Provided between the base and the die are means for lifting the latter and means for supporting the die bottom in the raised position after the die has been lowered. Such die construction makes it possible to reduce the time required for its assembly and disassembly, as well as for detaching the finished abrasive segment from the die walls.

Abstract: A mold for molding a boot or similar footwear from an elastomeric composition and simultaneously lining the footwear with a fabric, has first and second shells each having a cavity which complements the cavity of the other to form a large cavity which corresponds to the upstanding sides of the footwear and a third shell which has a cavity corresponding to the sole thereof. The three shells are assembled together with a rigid core member enclosed therein which defines the inside of the boot. The core member has an elastically expandable casing. Conduits are arranged in the core member for conveying a fluid under pressure to expand the casing.

Abstract: A method of manufacturing a voltage-nonlinear resistor which has a substantially symmetrical voltage-current characteristic and a large voltage-nonlinearity coefficient and which is thus well resistant to surge voltage. The method comprises: preparing a ZnO-based composition containing metal zinc, at least one metal oxide such as bismuth oxide and at least one spinel type crystalline compound such as spinel type crystalline chromium compound, shaping the ZnO-based composition to form a body, and sintering the body of composition in the air at 1,000.degree. C. or more.

Abstract: An apparatus for fabricating a plastic insulator having helical-shaped shields or screens, these shields radially protruding from an insulator rod. Two oppositely rotating rolls coact to form an infeed gap for the material forming the shields which is infed in a kneadable condition in transverse direction to the rolls. According to a first embodiment drive means serve to rotate the rolls about their axes and the insulator rod about its lengthwise axis. Means provide relative mutual movement of the pair of rolls and the insulator rod in the direction of the lengthwise axis of the insulator rod or parallel thereto, in order to simultaneously form the shield and apply the same to the insulator rod. According to a further embodiment both of the rolls have peripheral grooves and these rolls, with the exception of such peripheral grooves, bear against one another at their outer surfaces, and drive means serve for rotating the rolls for forming a shield or screen rod.

Abstract: The disclosure is of a process for moulding cellular polycarbodiimide, characterized in that it consists essentially in heating a panel by radiation and direct contact in a mould-die assembly, in compressing this panel when the foam reaches its softening point, so as to increase its density, in deforming it and rendering the material less friable, more elastic, smooth, calendered and of higher mechanical quality, while retaining its inherent qualities of non-inflammability, and finally in slightly cooling the mould after the moulding, for example by means of an air jet, so as slightly to harden the moulded product before the die is withdrawn and the said product is withdrawn from the mould.

Abstract: A method of manufacturing the molded hub of a print wheel of the type having a central axial passage of precise diameter and a plurality of elastically deformable, concentrically arranged character carrying radial arms. A metal ring carrying radial passageways is centered in the mold cavity used for forming the hub, etc., and a plastics composition is injected into the mold cavity only through the center of the ring and by way of the radial passageways whereby the metal ring becomes a unitary permanent part of the hub and defines the central axial passage. After the molding, the molded structure is released from the mold and the remainent central plastic plug easily is sheared from the ring, as by punching, for example. Remainent plastic material left within the radial passageways functions supplementary to maintain the stability and concentricity of the ring and hub assembly.

Abstract: A process for simultaneously batch-coating a number of electric components having radial connections wires extending in approximately parallel relation from the element to be covered utilizes a plate having a hole pattern therein for receiving the wires to retain the elements during coating. A synthetic foil is first placed over the plate and the wires are forced through the foil into the holes. A grid having openings therein formed by perpendicular walls for surrounding the elements is placed over the plate for use as a casting mold. A casting resin is deposited over the grid in excess quantity, and is then smoothed by moving a doctor over the grid. After the resin has hardened, the grid is removed and the individual elements, with the resin adhering to the synthetic foil, are separated.

Abstract: A strong, light-weight flexible bearing, particularly suitable for use in mounting a movable thrust nozzle to a rocket case, is made by stacking reinforced plastic shims, having the forms of concentric, spherical zones, alternately with layers of elastomer and bonding them together. A protective heat and flame barrier is formed by providing an especially refractory outer edge on each shim, which extends beyond the layers of elastomer. Each shim is made by:preparing a mold surface that forms a spherical zone of unique radius; filling a refractory cloth with a curable, liquid resin; placing segments of the cloth on the mold surface in an overlapping arrangement until the desired shim thickness is attained; preparing a second mold surface substantially parallel to the first: clamping this over the cloth segments on the first mold surface; and applying heat and pressure to the cloth segments until the resins are cured.

Abstract: A vibrating concrete screed utilizes a plurality of air-driven vibrators which are mounted on an elongated frame in a manner designed to achieve a unique vibration pattern throughout the length of the frame. An air-driven winch on the screed enables the screed to be winched automatically and at a controlled speed while the screed is being vibrated.

Abstract: An improved manhole concrete blockout for forming sewer pipe openings in the cast-concrete wall of a manhole where a hole is dug in the ground and at least one vertical hollow form is positioned within the hole and spaced apart from the surface which defines the hole and concrete is poured between the surface defining the hole and the form for forming a manhole wall. A plurality of form sections are connected together so that their outer surfaces can be positioned to become a longitudinal extension of the outer surface of the form. A blockout member is connected to the outer surface of at least one of the sections for forming an opening in the manhole wall, the end adjacent to the section being shaped to engage and conform to the outer surface of the section and the other end being shaped to conform to and engage the corresponding portion of the surface defining the hole so that an opening in the shape of the blockout member will extend through the wall when it is formed.

Abstract: This invention relates to U-shaped tunnel-type forms for poured concrete having an upper horizontal panel resting on two spaced vertical sides which, in turn, are separated on the ground by a combination of jacks and wheels. The bottom portions of the two sides are connected by plural horizontal retractile tie beams. The upper horizontsl panel is supported by articulated horizontal beams pivotal at their ends and in the middle to permit the panel to be deformed by curving it downward, thereby pulling toward each other the spaced corners or edges of the dihedrons formed by the junctures of the spaced vertical sides and the horizontal panel.

Abstract: In the invention, an apparatus is designed for producing spacer frames for insulating glass window structures, made up of lengths of hollow molding joined together by male cornerpieces. Hollows and spaces at the corner joins are sealed or filled by injection of a sealing composition forced in by the use of a female injection head designed to take up a frame corner, and a driver for pushing the frame corner structure into the injection head. There is furthermore a work table for the frame parts in the working position on injection of the compound or sealant, and gripper structures for keeping the hollow molding lengths, forming the corner, in the desired position. At least one of the gripper structures is able to be moved towards the put-in male part of the cornerpiece after the hollow molding part has been gripped.

Abstract: A composite ski is made by bonding a metal ski top to a molded ski body during the molding and curing of the body. The ski body is placed in the mold cavity of a two-part mold, and the metal top is movably supported on the other mold part. One end of the metal top is held by a spring-biased holding pin which permits the metal top to expand and contract relative to the mold part as the mold is heated and cooled while maintaining the metal top in alignment with the cavity.