Patent ID: 7686056

Claim:
Apparatus for applying strips of thermoplastic material to thermoplastic membranes, the strips each having an upstanding central portion extending lengthwise thereof and opposed flange portions extending widthwise from a base of the central portion, the apparatus comprising: a self-propelled housing assembly having drive wheels thereon for moveably supporting said housing; a guide assembly fixed to said housing assembly, said guide assembly comprising: a first pair of guide wheels mounted on said housing assembly for disposition around a previously applied first of the strips and movable along the first strip with one guide wheel on either side thereof; an axle; a second pair of guide wheels mounted on said housing assembly for disposition around a second of the strips to be applied and movable along the second strip so as to guide the second strip to a welding station mounted on the apparatus, the welding station being adapted to heat weld the second strip to at least one of the membranes; said first and second pairs of guide wheels being mounted on said axle proximate opposite ends thereof, respectively; and whereby the second strip is heat welded to the membrane along the length of the second strip equidistantly from the first strip.