Patent GB-877166-A (GB)
Title: Improvements in or relating to conveyor systems
IPC: B61B10/02
Filed: 1957-07-25
Abstract: 877,166. Overhead conveyer systems. KING, D. M. July 22, 1958 [July 25, 1957], No. 23610/57. Class 104 (2). In a conveyer system in which load-carrying trolleys 13 are propelled along an overhead track 12 by pusher dogs 10b depending from an endless chain 10 travelling on a track 11a above the trolley track 13 and a plurality of holding stations are spaced along the conveyer path there is provided at each holding station a ramp, vertically movable into and out of an operative position but which normally assumes the inoperative position, and a lever member movable into and out of a position in which it will hold the ramp in the operative position in which it will lie in the path of a laterally directed projection, carried by any pusher dog, to cause such dog to be lifted out of driving engagement with a trolley, there also being provided forwardly of each holding station, means to trip the lever member to allow the ramp to return to its inoperative position. In the arrangement shown the pusher dogs 10b, vertically movable in a clevis 10a carried by the chain 10, carry a laterally projecting roller 14 which engages a ramp 15, when moved vertically to the operative position shown in full lines in Fig. 2, to lift the dog 10b out of driving engagement with the load carrying trolley 13. The apparatus operates as follows. When a solenoid 26 is in the inoperative position the ramp 15, through the intermediary of links 25a and levers 23, 20 mounted on a collar 21 angularly movable about a shaft 22, is lifted to the operative position by a roller 19, engaging a bracket 17 attached to a vertically movable shaft 16, to move the pusher dog 10b out of driving engagement with the trolley and a pivoted stop-lever 18, connected by a pin-and-socket connection to the bracket 17 and provided with a laterallydirected extension 18a, Fig. 2, is held in a position to stop the trolley at the first or final station. When the solenoid 26 is operated the roller 19 is withdrawn from the underside of the bracket 17 and the ramp 15 drops either due to its own weight, or with the aid of a spring 27, to allow the pusher dogs 10b to move to the driving position and to pivot the stop-lever 18 out of the trolley blocking position so that the trolley can be propelled forwards. The trolley on leaving the first or final station engages a roller 29 to tilt a pivoted lever 28. The lever 28 on being tilted moves, through a rod 30 and the lever 24, the roller 19 into the position in which the ramp 15 is moved to the operative position. The lever 28 also, on being tilted, moves a roller 19<SP>1</SP>, in a preceding station, through a rod 38 and lever 23<SP>1</SP>, to a position in which a ramp 15<SP>1</SP> and a stop-lever 18<SP>1</SP> are moved to the inoperative positions, thus allowing a pusher dog to move a trolley, temporarily stopped thereat, to the next succeeding station. The trolley on being moved out of the station tilts the lever 28<SP>1</SP> to effect release of a trolley in a second preceding station. When the trolley reaches the first or final station it contacts a roller 33 to tilt a lever 31 and, through a link 34, a lever 35 to move, through a rod 37, the roller 191 and hence the ramp 15<SP>1</SP> to the operative position to raise a driving dog out of the driving position at the next preceding station. A trolley on stopping at the next preceding station similarly operates the levers 31<SP>1</SP> and 35<SP>1</SP> to affect a second preceding station. Pivoted stop-arms 39, 39a are provided at each station to prevent rearward movement of the trolleys.