880,744. Endless conveyers. FOOD MACHINERY & CHEMICAL CORPORATION. Sept. 25, 1959 [March 13, 1959], No. 32640/59. Class 78 (1). [Also in Group XVIII] A sorting apparatus comprises a conveyer on which are mounted carrier members which travel with the conveyer and are also movable transversely on the conveyer, guide means to constrain the carriers to follow a predetermined path as the conveyer moves, further guide means whereby the carriers may be guided along a path diverging from the said predetermined path, and a switching mechanism whereby the carriers may be engaged with either of the said guide means. The invention is described as employed for sorting articles by weight, the articles being fed to carriers 17 on the conveyer 15 from a check weighter 16 (Fig. 1), according to whose response to the weight of an article the switching mechanism 20 is automatically operated. Several embodiments are described, in all of which the conveyer comprises a pair of parallel endless chains 22, 24, interconnected by horizontal rods 18, and the guide means are rails disposed beneath the upper run of the conveyer to form three tracks 19A, 19B, 19C, for the carriers of articles which are respectively within, under or over a prescribed weight range. The article carriers 17 of Fig. 1 each comprise (see Figs. 2 and 3) a flat tube embracing two rods 18 and provided at the ends with upstanding flanges 58 to retain the article carried and a depending blade 60 engageable between the guide tracks. Fig. 13 shows a modified carrier 17a having flanges 58a and blade 60a, whilst a further modification, Fig. 15 (not shown), is generally similar to that of Figs. 2 and 3, except that the blade 60 is replaced by four pins for use with a conveyer whose guide tracks are monorails engageable between pairs of pins. In the embodiment shown in Fig. 17, the carriers 17c are simple tubes, each embracing only one rod 18c of the conveyer and provided with circular end members 58c serving both as article-retaining flanges and also for track-engaging. In this embodiment track 19A comprises the rails 92c, 94c which guide the two end members 58c of each carrier and tracks 19B and 19C respectively comprise the pairs 96c, 98c and 100c, 102c of rails, each of which pairs guides one end member 58c of each carrier. Switching mechanism.-In Fig. 1, the track 19 which guides the carriers from the region of the check weigher 16 towards the switch 20 terminates in a gate portion comprising a pair of flexible rails 78, 80, whose free ends are attached to a laterally reciprocable member 82 (see Fig. 4), held centrally of the conveyer by latch members 128, 130. Operation of the switch is by simultaneous operation of solenoids 148 (which frees the latch 128) and 110 to pull the ends of rails 78 and 80 to one side, or of solenoids 154, 112 to pull them to the other side. The three positions of these rail ends are aligned with grooves 86, 88, 90 in a plate 84 by which the article carriers are guided on to the appropriate one of tracks 19A, 19B, 19C. In another form of switching mechanism a switch gate comprises a short section of track pivotable about a horizontal axis and arranged to lie below the level of the guide tracks except when raised into the plane of the guide tracks by a rotary solenoid. In this form (Figs. 9 to 11, not shown) the switching of the carriers on to the over or under weight track is by the operation of the rotary solenoid of the appropriate one of two such switch gates which join the central track to the diverging tracks. In the form shown in Fig. 17, 304 and 306 are track elements pivoted at 308 and 310 respectively and joined by a rod 312 movable to one side or the other by solenoids 314, 320. The apparatus is employed as follows. The check weigher 16 transmits an electrical signal of the weight of each article to a memory unit. As each article carrier arrives at a predetermined position on the conveyer between the weigher and the switching mechanism, a switch is closed. This switch may either be cam-operated periodically from the conveyer drive or be closed by the interruption of a light beam between a lamp 162 and photo-cell 160 situated at the level of the guide tracks. As each carrier arrives at the conveyer switching mechanism, the article on the carrier interrupts a beam between lamp 172 and photo-cell 170 which are positioned above the conveyer, thereby closing a second switch in series with the first. The simultaneous closing of the two switches (the first indicating that the carriers are in the correct position relative to the switching mechanism and the second that there is an article on the foremost carrier) releases from the memory circuit a signal which will operate the switching mechanism of the conveyer in accordance with the weight of the article. This is then coveyed, by the appropriate guide track, to a required dispersal location at the end of the upper run of the conveyer. In the lower run of the conveyer the guide tracks 19B and 19C converge in such manner that all empty carriers, irrespective of the track on which they travelled on the upper run, are brought to the centre of the conveyer's width in readiness for reloading on the next traverse of the upper run.
