Patent GB-723421-A (GB)
Title: Improvements in conveyor systems
IPC: B65G47/48
Filed: 1951-06-21
Abstract: 723,421. Endless conveyers. FREEMAN (ENGINEERS), Ltd., A., and FREEMAN, A. June 16, 1952 [June 21, 1951; Aug. 15, 1951; Jan. 16, 1952], Nos. 14760/51, 19246/51 and 1271/52. Class 78 (1). A conveyer system arranged to cause an operation on or discharge of articles at selected stations along the path of the conveyer by means of a trip action consists of a travelling conveyer element, index devices disposed transversely of, and at intervals along, the element and a reader mechanism at each of said stations, each index device having a plurality of index elements movable alternately into projected or non-projected position to enable it to be set to a specific combination, and each reader mechanism having means controlled by the setting of all the index elements of an index device to initiate the trip action only if the index elements are set to the acceptable combination of the reader mechanism. As shown, Fig. 2, certain of the links of a conveyer chain constructed in the manner set forth in Specification 723,420 have welded to them depending bars 21 to which are secured last carriers 76, each carrier consisting of a hollow triangular section body inclined downwardly towards a door 72 at its lower end releasably held by a latch 74, so that a last 73 is releasably retained inside. The latch 74 which is pivoted at 79 is normally held in place by a spring 80 but may be released to dump the last from the carrier by engagement of the forward edge of a pivoted member 25 on the chain with a catch 62 (Figs. 9 and 10) at a discharge station, through a rod 77 connected between latch 74 and the rear end 78 of member 25. Also mounted on the chain at each carrier is an index device 24 consisting of a rod 23, Fig. 4, on which are threaded six index tumblers 28 and two unlocking tumblers 32. Rod 23 is slotted and a spring-pressed strip 30 is inserted in the slot to engage with one of six notches 29 in each of the six tumblers 28 by means of which each tumbler 28 can be locked in either of two positions, i.e. with an apex uppermost or a flat side uppermost. In order to change the orientation of the tumblers 28 the unlocking tumblers 32 have internal cam grooves 33 arranged such that if those tumblers, which are arranged one at each end of the strip 30, are simultaneously turned through a sixth of a turn from apex uppermost to flat side uppermost or vice versa, the strip 30 is depressed to unlock the tumblers 28 or released to lock the tumblers 28, respectively. In use a setting station, Fig. 5, is privided at a loading point for articles, e.g. lasts in a shoe factory, and the tumblers 28 of a carrier are set in a characteristic combination of apex-up or flat side-up positions according to the type or/and size of article, under control of an operator. For this purpose sets of weighted shoes 50, 51 are provided to engage the oncoming sets of tumblers 28 which are first unlocked by action of an abutment 34 on the tumblers 32. Portions 52, 53 respectively of the shoes 50, 51 bear against sets of cam discs 46, 47 respectively which sets are connected by gearing so that by manual rotation of a setting knob, not shown, any desired combination of " up " or " down " positions of the shoes 50, 51 can be given. The spaces between the corresponding upper and lower shoes 50, 51 then act as guideways for receiving the tumblers 28 in a certain combination of apex-up or flat side-up positions, any tumbler 28 not in correct position being automatically turned into such position by engagement with the forward edge 50<SP>11</SP> or 51<SP>11</SP> of the upper or lower corresponding shoe. After setting an abutment 35 engages the tumblers 32 so as to lock the tumblers 28 in set position. The carrier loaded with a last of a type and/or size corresponding to the setting now travels past a series of discharging stations each having a characteristic number of rockable levers of each of the two types 66 or 661, Figs. 9 and 10, corresponding to the two positions of the tumblers 28, mounted side-by-side in a set on a common shaft 65. A pivoted plate 61 carrying the catch 62 is normally held in a raised position out of the path of the forward edges of the pivoted members 25 on the chain by a finger 71 on each of the levers 66<SP>1</SP> engaging its underside and trapping it against an overhanging part 70 of these levers, whilst levers 66 are held in a lowered position by a stop 69. Both types of levers are unaffected by tumblers 28 having flat sides uppermost, but tumblers having apexes uppermost raise the levers in passing. Raising of a lever 66 moves it into contact with plate 61 and keeps this in raised position, while raising of a lever 66<SP>1</SP> lowers its finger 71 and allows plate 61 to drop, provided none of the levers 66 is raised. Thus in order that plate 61 may be lowered to place the catch 62 in the path of the pivoted member 25 associated with a set index device for dumping the last from the associated carrier 76, the passing index device must have tumblers 28 which are flat side-up in register with all the levers 66 and tumblers 28 which are apex-up in register with all the levers 661.