A trolley for a conveying system includes a first trolley arm with a trolley wheel rotatably mounted thereon, a second trolley arm with a trolley wheel rotatably mounted thereon, and a load bar. The trolley wheels roll along a track of the conveying system to move the trolleys along the conveyor track....http://www.google.es/patents/US7334527?utm_source=gb-gplus-sharePatente US7334527 - Trolley attachment
