Abstract: A process for production of a re-entrant article, such as a vehicle mud guard, comprising attaching a sheet of thermo-plastic material, by its opposite edges, to trolleys on a machine, the trolleys being movable towards one another, heating the sheet to soften it, raising a former under the sheet to cause it to take up the required re-entrant form, the trolleys moving inwardly as this occurs, and then cooling the sheet to cause it to set in the required configuration.

Abstract: A clamping frame for use in plastic forming apparatus which includes a plurality of tubular elements joined together to define an opening over which a sheet of plastic material is mounted with the edges of the plastic sheet being held against supporting surfaces of the tubular elements by clamps. Each tubular element is formed of a thermally conductive material and includes an interiorly disposed heating element located adjacent the supporting surfaces of the tubular element. The tubular elements include a plurality of interconnections to permit selective positioning of the tubular elements with respect to one another for varying the size of the opening defined thereby, and these interconnections also electrically connect the heating elements within the tubular elements at all adjusted positions thereof to form a closed electrical circuit which may be connected to an electrical source whereby the edges of the plastic sheet between the clamps and the tubular element supporting surfaces may be heated.

Abstract: Apparatus for molding material including a frame for holding the material and which is movable away from the molding die so that the material can be loaded and unloaded into and out of the frame at positions clear of the die. The frame has spring biased movable mountings having pins which penetrate the material and hold this in a resilient manner during molding. A turntable support is provided for holding two of the frames on opposite sides of a vertical axis, and this holds one frame in a convenient loading position while the other frame is holding material being molded.

Abstract: An apparatus for producing a corrugated sheet from a web of deformable material, for use in cooling towers and the like, includes an endless conveyor which is adapted to move along a predetermined path of travel and on which are mounted a plurality of web molding trays. The trays have a plurality of corrugations formed therein extending generally transversely of the path of travel and means are provided for selectively locking the trays on the conveyor with the corrugations located at predetermined acute angles with respect to the path of travel of the conveyor so that the angle of the corrugations formed in the web can be varied. An air knife arrangement is provided for urging the web against the corrugations in the trays to form the corrugations in the web.

Abstract: Apparatus is disclosed for manufacturing a resilient cushion of foamed plastics material with an integrated cover cloth. The apparatus includes means for accepting a piece of cover cloth between frames to dispose the cloth across the mouth of a vacuum mould and control the peripheral contraction of the cloth as it is drawn into the mould by vacuum, prior to casting the foamable plastics mix into the mould. The apparatus limits the amount of peripheral contraction permitted in the cloth to avoid wrinkles or plaits in the surface of the finished cushion.

Abstract: A table for use in plastic forming machines, the table including a plurality of upstanding tubular support members arranged in a predetermined pattern, a plurality of alternately usable platform members, each such platform member being of a different size to support different vacuum molds and each being mountable on upstanding tubular supports at selected positions on the table. A plastic material clamping frame having readily adjustable side elements for varying the size of the clamping frame is arranged to be selectively positionable, at all variable sizes thereof, to thereby hold the edges of a sheet of plastic material along and beneath the edges of different vacuum forming molds mounted on a platform member supported by the tubular support members at the selected positions thereof.

Abstract: A differential pressure forming machine including a pair of endless, sheet supply chains for supporting a deformable thermoplastic sheet and forwardly advancing the sheet, a heater for heating the thermoplastic sheet, a mold for differential pressure forming a shape in the heated sheet, a drive chain for driving the sheet supply chains, a clutch for selectively coupling and decoupling the drive chain and the supply chains, a pair of pneumatic cylinders mounting reciprocally movable pistons which are coupled to opposite ends of the drive chain for driving the sheet support chains in forward and reverse paths of travel, and control mechanism for operating the clutch and the pistons in timed relation so that the sheet support chains and the sheet are incrementally indexed only when the chain moves in said forward path of travel.

Abstract: An adjustable clamping frame for clamping the peripheral edges of a sheet of plastic material during the plasticizing and vacuum forming thereof, such frame including a first pair of parallel side elements having clamping elements mounted thereon and being selectively adjustable toward and away from one another to vary the spacing therebetween, and a second pair of side elements selectively mountable in any of a plurality of facing slots spaced along the length of the first pair of side elements.

Abstract: A method and apparatus for making biological discs comprises the steps and means for welding the longitudinal edges of a pair of identical rectangular plastic sheets together to form a single large sheet. This single large sheet is conveyed to a heating and vacuum forming station where the sheet is heated and vacuum formed to have a plurality of convex cup-like projections formed in the surface thereof. The sheet is then moved to a cutting station where heating mechanisms form openings therein for accommodating an axle and a plurality of tie rods, and the sheet is cut in circular configuration by a cutting device shiftable on a radius of predetermined magnitude.

Abstract: A tray-like container of a plastic coated paper blank having a base panel, which has four or more even numbers of side edges, side walls, corner portions, a peripheral portion extending along side walls and corner portions, and a pig-tail like folding line formed in each corner portion of the peripheral portion, of which a flange of the tray-like container is formed. The pig-tail like folding line assists in the outward bending of the peripheral portion so that it forms the outwardly projecting flange of the tray-like container. The outer shape of the tray-like container is forcedly molded by a movable and stationary complementary moulds.

Abstract: A table for use in plastic forming machines, the table including a plurality of upstanding tubular support members arranged in a predetermined pattern, a plurality of alternately usable platform members, each such platform member being of a different size to support different vacuum molds and each being mountable on selected ones of the upstanding tubular supports. A plastic material clamping frame having readily adjustable side elements for varying the size of the clamping frame is arranged to be selectively positionable, at all variable sizes thereof, between selected tubular support members to thereby hold the edges of a sheet of plastic material along and beneath the edges of different vacuum forming molds mounted on a platform member supported by the tubular support members.

Abstract: Thermoforming apparatus adapted to accommodate molds of different lengths to form molded parts in a horizontal web comprises a vertically movable support. A mold base assembly carried by the support includes a flat-topped rectangular basic mold base secured horizontally to the support. A plurality of flat-topped straight mold base extension segments are removably secured together in side-by-side relationship forming a rectangular array. The array is removably secured to the basic mold base and support. A first vertically movable straight gate is secured to the free end of the basic mold base. A second vertically movable straight gate is removably secured to the segment at the free end of the array. Any one or more segments along with the second gate can be removed from the mold base assembly without disturbing the basic mold base and remaining segments. The second gate can then be attached to the segment at the free end of the shortened array.

Abstract: A method for forming and pressing a foil to a board made of wood shavings, fibers and the like, in a double plate press having at least one first plate movable in a closing direction toward the other second plate and employing a first pivotal lever having a support surface and a second pivotal lever forming a top clamping surface, comprising placing at least one foil in alignment with at least one surface of the board and depositing the board and the foil onto a support surface. Thereafter, the second lever is pivoted in a first direction in order to engage a clamping roller at the end thereof onto the board. The two levers with the supported and clamped board are then displaced longitudinally into the press between the two press plates.