Abstract: Apparatus for applying thermoplastic strips to thermoplastic membranes, each strip having an upstanding central portion and opposed flange portions extending widthwise therefrom. The apparatus includes a housing having drive wheels for movably supporting the housing. A guide assembly fixed to the housing includes a first pair of guide wheels for disposition around an applied first strip and movable along the first strip with one guide wheel on either side thereof, and a second pair of guide wheels for disposition around a second strip to be applied and movable along the second strip, so as to guide the second strip to a welding station on the apparatus. The welding station is adapted to heat weld the second strip to the membranes along the length of the second strip equidistantly from the first strip.

Abstract: Apparatus for heat welding together thermoplastic membranes mounted on a surface includes a frame, a support member connected to the frame, a nozzle mounted on the support member to receive heated air, weld wheels mounted on the support member adjacent to, and immediately following, the nozzle for pushing a heated portion of an upper membrane toward a lower membrane to effect a weld, wherein the support member is adapted to be fixed to the frame member in a first position proximate a first side of the frame for welding the two membranes together, is releasable from the first position, is movable to a second position nearer a second side of the frame, and adapted to be releasably fixed to the frame at the second position for welding a membrane to an underlying edge piece mounted on a free edge of the surface.

Abstract: A weld wheel assembly for disposition on a membrane welding machine, and for positioning a weld wheel adjacent a nozzle hot air outlet for pressing an overlying roof membrane heated by the nozzle against an underlying roof membrane heated by the nozzle, for welding the membranes together. The assembly includes a weld wheel rotatably mounted on an axle which is moveable toward and away from the membranes, and pressure exerting structure mounted on the machine and operable to bias the axle toward the membranes during operation of the machine.

Abstract: A method for attaching thermoplastic strips to a roof of thermoplastic roof membranes includes the steps of providing strips of thermoplastic material, the strips each comprising an upstanding central portion extending lengthwise thereof, and opposed flange portions extending widthwise from the central portion, positioning the strip proximate a selected position on the roof for attachment to the roof, providing a self-propelled apparatus having means for affixing the strip onto the roof, and directing the apparatus along a line delineating the selected position on the roof to guide the strip into position adjacent the line and to affix the strip onto the roof membrane alongside the line.

Abstract: A nozzle for directing discrete streams of air along separated and parallel first and second paths includes a chamber for receiving air of a selected temperature, a first outlet arm extending from the chamber and having a first outlet at a distal end thereof and in a first outlet plane, and a second outlet arm extending from the chamber and having a second outlet at a distal end thereof and in a second outlet plane, an axis of the second outlet arm being generally parallel with an axis of the first outlet arm, the second outlet plane being offset from the first outlet plane.

Abstract: A nozzle for directing discrete streams of air along separated and parallel first and second paths includes a chamber for receiving air of a selected temperature, a first outlet arm extending from the chamber and having a first outlet at a distal end thereof and in a first outlet plane, and a second outlet arm extending from the chamber and having a second outlet at a distal end thereof and in a second outlet plane, an axis of the second outlet arm being generally parallel with an axis of the first outlet arm, the second outlet plane being offset from the first outlet plane.

Abstract: A weld wheel assembly for disposition on a membrane welding machine, and for positioning a weld wheel adjacent a nozzle hot air outlet for pressing an overlying roof membrane heated by the nozzle against an underlying roof membrane heated by the nozzle, for welding the membranes together. The assembly includes a weld wheel rotatably mounted on an axle which is moveable toward and away from the membranes, and pressure exerting structure mounted on the machine and operable to bias the axle toward the membranes during operation of the machine.

Abstract: An articulating plate assembly for retaining sheets of roofing material on a roof surface includes a plate defining (i) a generally hemispherically-shaped recess in a central portion of a first surface thereof, and (ii) an aperture disposed in the recess and extending through the plate, and a fastener having (i) a shank portion configured to pass through the aperture and to engage the roof surface, and (ii) a head portion having an underside of a curved configuration generally complementary to the recess.