Patent GB-985054-A (GB)
Title: Improvements in or relating to conveyors
Inventor: BLACKLOCK LEO BENSON
IPC: A21C13/02
Filed: 1962-06-05
Abstract: 985,054. Conveyers. BAKER PERKINS Ltd. May 24, 1963 [June 5, 1962], No. 21752/62. Heading B7L. [Also in Division B8] A conveying apparatus comprises a plurality of independent article carriers 2 on rollers 3 which traverse a guide track circuit between an article feed station B and an article delivery station A, the circuit including a tortuous portion formed by a plurality of spaced parallel horizontal guide track sections 4, 5, 6 secured to a main frame 1. Elevator means 10 are provided for transferring carriers 2 from the last track 4 to the first track 6, de-elevation means 7, 9 for transferring the carriers from the first track 6 progressively through intermediate tracks 4, 5 to the last track 4, and endless chain driven pushers 8, 11 on the de-elevator 7 and elevator 10 propel the carriers around the circuit which may have its length reduced by rendering the chain pushers inoperative in respect of at least one uppermost or lowermost track section whereby that track section and its immediately succeeding track section are isolated from the circuit. Feed and delivery pushers 14, 12 associated with feed and delivery conveyers 15, 13, move articles into and out of the circuit at stations B and A. The de-elevator carriages 7, 9 are actuated by crank mechanisms 19, 25 and while one is in its up position the other is in its down position. The elevator carriage 10 is actuated in phase with de-elevator carriage 7 by means of a cable 28 passing over pulleys 29 and attached to the de-elevator carriage 9. Each of the carriages has rollers 16, 20, 25 which run in vertical guide rails 17, 21, 26. In the embodiment of Fig. 1 each carriage 7, 9, 10, has three pairs of rails of length equal to one or a multiple of article carriers 2 spaced vertically at twice the vertical spacing of the six guide track sections 4, 5, 6 which have their ends vertically aligned except the uppermost track 6 which extends over the de-elevator carriage 9. The operating cycle, Figs. 2-6 (not shown) which may be controlled by micro switches or cams, commences with a carrier on the bottom track of the carriage 10 being loaded from feed conveyer 15 and being elevated by repeated transfer between the two carriages 9, 10, to the uppermost guide track 6. Succeeding loaded carriers move the first carrier to the opposite end of the guide track 6 where it transfers to the de-elevator carriage 7. The carrier then moves the full length of each guide track, and is lowered at each end by either the de-elevator 7 or 9 until it is discharged to the delivery conveyer 13. A further deelevator carriage 7a may be introduced between the ends of the guide tracks to reduce the circuit length. This carriage contains the same number of rails as the fixed guide track but only alternate pairs of rails incorporate pushers. The circuit length may also be reduced by increasing the stroke of the crank mechanism 19, 25. Over rails and side rails may be provided at the ends of the fixed guide tracks 4, 5, 6 to stabilize the carriers during transfer. In a further embodiment, Fig. 11, the carriers 102 comprise plates 103 having downturned stabilizer and conveyer arms 107, 108 at one end and upturned stabilizer and conveyer arms 105, 106 at the other end, each of which mounts a track engaging roller 109. One rail of each fixed pair of tracks, in this case, is vertically displaced from the other. Adjacent plates 103 are joined in horizontal travel by vertically engaging and disengaging coupling means 104. The uppermost and lowermost pairs of rails extend at the front end beyond the vertically aligned intermediate rails, by an amount equal to one or more lengths of the carrier. The carriers are propelled along the fixed guide rails by forks 138 mounted on horizontal endless driven chains 136 and engaging the conveyer arms 106, 108. The carriers are conveyed vertically by forks 124 attached to vertical endless chains 121, 122 at the rear end of all the guide rails, at the front end of the upper and lowermost rails and at the front end of the intermediate rails. Slots 141 in all the rails except the lowermost pair, with guide surfaces 142 between all the rails, allow stabilized vertical travel for the stabilizer arms 105, 107 during elevation or de-elevation.