Patent ID: 8414722

Claim:
An apparatus for welding a synthetic strip to a roofing membrane that is attached to a roofing construct, the synthetic strip having a central raised portion that extends along a longitudinal length of the synthetic strip, the synthetic strip having flanges extending widthwise from the central raised portion, and the synthetic strip having a substantially planar underside portion, the apparatus comprising: a self-propelled housing having a drive wheel for movably supporting the housing relative to a roofing membrane; a first guide-wheel element mounted to the housing and positioned in or underneath the housing and the first guide-wheel element having a peripheral channel adapted to engage and receive the planar underside portion of the synthetic strip and guide the synthetic strip, wherein the guide-wheel receiving channel has a channel width adapted to receive the total width of the synthetic strip; the drive wheel being mounted to said housing, the drive wheel being motor drive and having a circumferential channel adapted to receive and apply pressure downwardly against the central raised portion of the synthetic strip as the housing passes over the synthetic strip; and the drive wheel further comprising flange-engaging circumferential edges adapted to engage and apply pressure downwardly to the flanges of the synthetic strip.