Patent ID: 8316990

Claim:
A trolley for movement along an elevated track to support a person who has fallen off of a structure adjacent the track, said trolley comprising a frame having at least one roller, a connector mounted on the frame, and at least one trolley immobilizing assembly mounted on the frame, said at least one roller enabling said trolley to roll along a surface of the track in a longitudinal direction, said connector having a lanyard releasably secured thereto, the lanyard connected to a safety harness to be worn by the person and to suspend the person from said trolley, said trolley immobilizing assembly comprising a movable engagement member and a flexible strap, said strap secured to said movable engagement member, a guide member releasably secured to said frame, said guide member holding said strap in a stowed position wherein said strap is adjacent said lanyard, said movable engagement member being biased in a position away from the track, wherein pulling on said strap separates said guide member from said frame so that said strap hangs from said movable engagement member and causes the movable engagement member to be pulled into engagement with the track thereby releasably fixing said trolley at a fixed longitudinal position on the track so that the person can swing below said trolley while fixed in the fixed longitudinal position on the track, and wherein releasing said strap causes the movable engagement member to return to the biased position thereby releasing the trolley from the fixed longitudinal position on the track so that momentum of the swing of the person moves said trolley along the track to another longitudinal position thereon.