Patent GB-742488-A (GB)
Title: Improvements in or relating to conveyor systems
Inventor: BURROWS ARTHUR THOMAS CHARLES
IPC: E01B25/26
Filed: 1953-03-12
Abstract: 742,488. Overhead conveyer track switch points. KING, Ltd., G. W. Jan. 15, 1954 [March 12, 1953], No. 6868/53. Class 104 (2). A conveyer system in which load carrying trolleys are pushed along a track by pusher dogs carried by an endless chain running above the track has at the junction between main and branch tracks 10, 11 a switch tongue 17, 18 angularly movable between its two positions and provided at its free end with an auxiliary switch tongue 20 capable of pivotal movement relative to the switch tongue 17, 18 so as to be automatically set in one or other of the two positions depending on the angular setting of the switch tongue 17, 18. The switch tongue comprises an elongated plate 17 which supports a plate 18 radiused at one end to correspond with the radius formed on a plate 12 and radiused at the other end to accommodate the radiused end of an auxiliary switch tongue 20 pivotally mounted on the plate 17 by means of a pin 21. The angular movement of the auxiliary switch tongue 20 is limited by a pin 22 carried thereon engaging a slot 23 in the plate 17. The switch assembly is moved by an electrically, mechanically or manually-operated lever 16 pivotally mounted on a pin 15 and attached at its forward end to the plates 17, 18. Interposed between a plate 14 (fixedly clamped to the plate 12 by bolt 14<SP>1</SP>) and lever 16 and supported on a slightly angularly movable rod 25 is a spring 24 which ensures a snap movement of the lever 16 past its dead centre position to either of its two positions. When the switch tongue 18 is moved in an anticlockwise direction from the position shown in Fig. 1 the plate 17 is shifted to a position underlying the outer rail of the track 10, an edge 26 of the plate 18 engages the edge of the outer rail of the track 10 and the auxiliary switch tongue 20 abuts the edge of the outer rail of the track and is moved in a clockwise direction limited by the slot 23. In this position the auxiliary switch tongue 20 and a curved edge on the plate 18 direct trolleys on to the branch track 11. An ejector mechanism, shown in Fig. 3, moves trolleys over the switchpoint when the switch point is set for the branch track 11. The mechanism comprises a lever F pivoted at P at one end and at the other end carrying a bell-crank A, B, the arm B of which is connected by a link E to an arm D of a bell-crank C, D pivotally mounted about a fixed pivot K and carrying a push-dog L on the end of arm C. When the switch tongue is set for the branch track 11 the arm A is projected across the track 10 and when a trolley arrives at the switch point the pusher-dog driving the trolley engages the arm A which is moved to a position A<SP>1</SP> and at the same time an auxiliary push-dog L on the arm C engages the trolley which is propelled from a position X to a position Y as the arm C is moved to a position C<SP>1</SP>. When the main chain pusher dog disengages the arm A in the position A<SP>1</SP> the mechanism is returned to its initial position by springs or other suitable devices. When the track 10 is open the arm A is moved to a position A<SP>11</SP>.