Patent GB-890324-A (GB)
Title: Improvements in, or relating to, apparatus for treating workpieces
Inventor: HUMPHREYS GEORGE
IPC: B65G23/40
Filed: 1956-12-07
Abstract: 890,324. Endless conveyers. A.E.I.-BIRLEC Ltd. March 7, 1958 [Dec. 7, 1956; Oct. 19, 1957], Nos. 37413/56 and 32711/57. Class 78 (1). In apparatus comprising two work-treating stations arranged at longitudinally spaced points along a conveyer which provides a series of equally-spaced article-conveying pockets, and in which the conveyer is driven step-by-step and transfer mechanism is provided which is operated between successive steps of the conveyer movement, the relationship between the spacing of the stations, the pocket pitch and lengths of the conveyer steps is such that a different pocket is brought to rest in register with each of the stations in sequence during each cycle of steps equal to the number of stations and, except during an initial starting period, every pocket is brought to rest in register with one or other of the stations before it travels beyond the machine. In one embodiment, Figs. 2 and 3, the conveyer consists of an endless series of interlinked transverse trays 16 which form the pockets, each carrying a metal billet 18. There are two work-treating stations, each comprises a pair of heating coils 3, 4 through which the billets are passed in turn by the transfer mechanism. The latter comprises two pneumatic cylinders 11 whose piston-rods 12 are connected to sliders 13 each provided with a depending claw (Fig. 1, not shown). A further transfer mechanism 8 comprising two reciprocating grippers 151 is provided for discharging the billets from the two pairs of coils. The cylinders 11 are operated alternately between successive steps of the conveyer so that the claws are alternately reciprocated in the transverse planes 17, Fig. 3. The planes 17 are separated by a distance equal to four tray pitches and the conveyer is driven in steps of one tray pitch by ratchet mechanism 24 operated by a cylinder 23 and toggle linkage 20, 21. Each claw therefore reciprocates when every second tray comes to rest opposite it and the first claw discharges alternate billets while the remainder are discharged by the second claw. The relationship between the interstation spacing and the tray pitch may be varied provided the former is a multiple of the latter such that this multiple plus unity is not a multiple or sub-multiple of the number of stations. In a second embodiment, Fig. 5, there are again two stations but the transfer mechanism consists of a single pneumatic cylinder which reciprocates two claws simultaneously in the two planes 17 which are spaced apart by two and a half pocket pitches. The conveyer is driven in alternate steps of half a tray pitch and one and a half tray pitches by ratchet mechanism 30 operated by cylinder 36. As a result the billets are equally distributed to the two pairs of heating coils, one of the claws idling between two adjacent trays at each stroke. The Specification also discloses formulµ for obtaining other values of interstation spacing and lengths of the conveyer steps where the number of stations exceeds two, e.g. where there are three stations these are spaced by three and one third tray pitches and the conveyer is moved in cycles of two steps, each of two thirds of a tray pitch, followed by a step of one and two thirds tray pitches.