Conveyor system for drive-in restaurants

Claim 1

A conveyor system comprising: a. a conveyor track including a closed delivery loop and a series of station loops each diverging from said delivery loop at one point and re-converging therewith at another point, b. a series of carriages powered to move along said track continuously in the same direction, each of said carriages being driven by an electric motor mounted thereon and which derives its electrical power from a pair of electrically chargEd rails forming elements of said track, with which said carriage has moving contact, each of said carriages corresponding to one of said station loops, c. a series of normally open mechanical switches each operable when closed to divert carriages from said delivery loop into one of said station loops, d. a switch operating means for each of said mechanical switches and operable to close said switch, said operating means including cooperating members carried respectively by said track just before the switch point and by each of said carriages, whereby to be brought into operative relationship by the movement of said carriages along said delivery loop of said track, said cooperating members being different for each carriage-switch combination whereby the mechanical switch for each station loop will be closed only by the carriage corresponding to that station loop, said cooperating members remaining in operative relationship only long enough to divert the associated carriage, e. means for stopping each carriage automatically at a selected point of its corresponding station loop, f. manually operable means for re-starting said carriage, and g. collision-preventing means including means operable by a first carriage as it approaches any point of track convergence between said station loops and said delivery loop, along either of said loops, to stop any second carriage approaching said point of track convergence along the other of said loops, and to re-start said second carriage only after said first carriage has passed through said convergence point, said collisionpreventing means comprising means electrically insulating a section of at least one of said rails from the remainder of said rail, at points of both of said track loops at points of both of said track loops just before said point of track convergence, a concuctor connecting each of said insulated rail sections to the remainder of its associated rail, a normally closed first switch in each of said conductors, a pair of electric switch-operating devices each operable when energized to open one of said first switches, and to close a holding circuit for said switch-operating device to maintain said first switch open, a normally closed holding switch in each of said holding circuits, an operating circuit for each of said switchoperating devices, a normally open second switch in each of said switch-operating device circuits, said second switch being mounted adjacent said track at points just before said convergence point, respectively adjacent each of the approaching tracks, and operable to be mechanically engaged and closed by a carriage approaching on said track, the second switch closed by a carriage on either approaching track being operable to complete the circuit of the switch-operating device associated with the other approaching track, and means carried by the common track leaving said point of convergence, and operable to be engaged and actuated by any carriage leaving said point of convergence to open both of said holding switches.