Patent GB-842230-A (GB)
Title: Endless chain conveyors
IPC: B65G17/42
Filed: 1957-12-17
Abstract: 842,230. Endless chain conveyers. CHAIN BELT CO. Dec. 17, 1957 [Jan. 9, 1957], No. 39251/57. Class 78 (1). [Also in Group XXV] In endless chain conveyers having load carrying or pusher flights the flights are detachably attached to the chain by resilient connecting members formed on the flights and adapted to be deflected in connecting a flight to the chain and to snap into positions in which they lock each flight to a link of the chain. In one embodiment, Figs. 3 and 7, each flight 24 comprises a slat plate 38 having depending resilient legs 37 which are adapted to straddle a pair of outer link plates 33 of a roller chain which comprises alternate outer link plates 33 and inner link plates 28. The inner link plates 28 are secured together by bushes 29 which carry rollers 31, while the outer link plates are connected by the link-pins 34. The pins 34 are secured to the outer link plates 33 at only one side of the chain and extend slightly beyond the link plates at both sides. The legs 37 of the flights are provided with apertures 39 to receive the pins 34, and also lead-in grooves 40. A reinforcement 42 extends between the two legs of each flight. The flights may be of resilient plastic material or steel. In assembling, the loose outer link plate 33 of each pair is placed in position and the flight pressed downwards into the chain-line position, Fig. 7, in which the legs are forced apart by the pins engaging the grooves 40. Upon further downward movement of the flight to the full-line position, Fig. 7, the legs snap back to receive the ends of the pins 34 in the apertures 39 so that the legs are locked to the chain and also hold the loose link plate 33 in position. The apertures 39 may be closed at their outer ends in which case both link plates 33 may be loose on the pins 34. Grooves 41 in the legs 37 allow the insertion of a screwdriver blade to prise the legs apart for removal of the flight. A stop member 47 is formed on the flight to restrict flexing of the links at those link pins situated adjacent the trailing edges of the flights so that whereas a following flight can drop below a preceding flight the reverse cannot happen. The leading and trailing edges of the flights have complementary curved surfaces to allow of flexing both around a reversing pulley and around a snub pulley. In another embodiment, Fig. 11, slat plates 63 are secured to both outer and inner pairs of link plates. For this purpose the flights are of two types, viz. that shown, in which the flight has flexible legs which pass between the outer link plates, and a complementary type in which the legs straddle the inner link plates. In each case the legs have, on their sides facing the link plates, lugs 65 having inclined surfaces and arranged so that, when a flight is applied to the chain, the legs are flexed until the lugs 65 engage in apertures 61 in the link plates to lock the flight in position. In a modification, Fig. 14, the apertures in the link plates are omitted and the legs 71 of the slat plates 69 have lugs 73 which engage below the link plates 59 of the chain. In a further embodiment, Fig. 16, the flights are pusher blocks 75, which are fitted at spaced intervals to the chain by legs 76 similar to the legs 37, Fig. 3. In this case, only the links to which the flights are to be attached have loose outer link plates, the remaining links being of orthodox construction. The blocks 75 may have apertures 79 for mounting push plates 77. In another embodiment, Fig. 18, a pair of parallel chains is provided, each chain having clips 81 secured to them, opposed clips on the two chains being interconnected by cross-bar flights 85. Each clip is of inverted U-shape providing resilient legs 82 similar to the legs 37, Fig. 3, the adjacent end of the bar 85 being secured in a socket 83 on one of the legs 82. In a further embodiment, Fig. 20, each flight comprises a slat plate 89 provided with legs 90 each of which has a pair of slots 91 forming resilient end portions 93. The slots 91 are enlarged centrally of their length to receive reduced portions of the chain pins 92 when the flight is pressed on to a chain link. In a still further embodiment, Fig. 21, the flights are in the form of crescent-shaped plates 94 each of which is secured to one leg of a V-shaped clip 96 similar to the clips 81, Fig. 18, the clips being pressed on to a chain 23 arranged with its link-pins vertical.