Cart pushing apparatus

Apparatus for moving a plurality of aligned carts along a predetermined path comprising a frame construction which includes a pair of parallel elongated frame members, each cart including a frame structure adapted to straddle said frame construction, a pair of parallel elongated pusher bars, means for orienting said bars with respect to said frame members so that they are superposed and aligned therewith, said means including two pairs of substantially vertically oriented legs, means for pivotally connecting one end of each pair of legs to a frame member, means for pivotally connecting the other end of each leg to a pusher bar so that each pusher bar is connected to a frame member by a pair of said legs, means for oscillating said pusher bars with respect to said frame members along a path parallel to said bars and frame members, means mounted on said pusher bars for engaging a portion of at least one cart and causing it to move as the pusher bars move in a first direction, said engaging means comprising a plurality of lugs, means for mounting said lugs on the pusher bars so that they are axially aligned along the longitudinal axis of said bars in spaced-apart relationship, means for biasing said lugs in an upward direction so that a portion of each lug projects above the top surface of the pusher bar, said lugs being movable against such biasing action by exerting a downward force against said lugs, means on each cart frame adapted to be engaged by said lugs, said means including a pair of elongated parallel channel members, means for attaching said channel members to the cart frame so that they are aligned directly over said pusher bars and parallel therwith, a plurality of pusher plates, means for mounting said plates within the channel members in spaced-apart relationship so that they extend laterally with respect to the longitudinal axis of the channel members, said lugs adapted to engage said pusher plates as the pusher bars are caused to move in said first direction, said frame members and said pusher bars being shorter in length than the alignment of carts so that the means mounted on the pusher bars engage less than all the aligned carts, said cart when moved causing the other aligned carts ahead of it to move as well, said engaging means permitting said cart to remain substantially stationary as the pusher bars move in a second direction, and means for guiding said carts along said predetermined path.