Abstract: An improved apparatus and method for joining two or more thin sheets of thermoplastic materials along a welded seam includes a welding assembly and a means for feeding the thermoplastic sheets to the working area of the welding assembly. The welding assembly includes a heated platen welding press coupled with a welding tool, an energy generator electrically connected to the welding tool and control means electrically connected to the welding press, the welding tool and the energy generator. The welding press includes a pair of opposed platens, means for heating each of the platens and pressing means for displacing at least one of the opposed platens in the thickness direction of the thermoplastic sheets. Pressure is applied to the thermoplastic sheets by using the pressing means to displace at least one of the heated platens in the thickness direction of the thermoplastic sheets.

Abstract: The invention concerns how the loop portion of a VELCRO fastener can be RF welded to a compression sleeve or other similar article. By using a simpler two-step method, in which the loop portion is provided with a backing laminated thereto, both labor and material costs have been reduced over the prior art five-step method.

Abstract: A method and apparatus for supporting sheet material such as cloth during operations thereon such as cutting wherein a pattern is placed on a supporting surface provided with a plurality of pins extending through apertures in the surface, the pins are lowered below the surface for removal of the pattern whereupon sheet material is placed on the surface, typically a plurality of plies being layed up in a stack, and simultaneously the pins are moved through the sheet material to maintain alignment and matching of the plies in the stack. The pattern then is placed on the sheet material in a position determined by the location of the pins, and the material is shaped such as by cutting. A plurality of separate pin holding and supporting devices of narrow width are spaced lengthwise along the apparatus and independently movable lengthwise toward and away from each other. Pins of adjacent rows can be closely spaced together thereby achieving a grid pattern wherein the pins are relatively closely spaced.