841,502. Endless conveyers. PFIZER & CO. Inc., C. March 24, 1958 [April 4, 1957], No. 9314/58. Class 78 (1). [Also in Group XVII] An apparatus for opening carton bottoms to unload their contents, comprises a first conveyer 24, Fig. 2, adapted to carry the cartons 12 past flap-engaging means 50 for opening the outer flaps 20 as the cartons move with the separation between the outer flaps 20 parallel to the direction of carton movement, and a second conveyer 28 at right-angles to the first conveyer and carrying the cartons 12 past flap-engaging means 80, 82, 84 for opening the inner flaps 22. The second conveyer has means 76 for maintaining the articles in the opened cartons 12 until the cartons reach a discharge position 78, Fig. 5. The second conveyer 28 has positive drive means 72 for the cartons, whereas the first conveyer 24 has slidable drive means 32 capable of slipping relatively to the cartons 12 to permit the cartons to be loaded and transferred therethrough in accordance with the operating phase of the second conveyer 28. Step-by-step control means. A pair of alternately operating carton restraining means 54, Fig. 2, are spaced along the first conveyer 24. Each restraining means 54 includes a plunger 56 reciprocally operated by pneumatic cylinders 58. The cycle of movement of the plunger 56 is governed only by the time required for the second conveyer 28 to remove a carton 12 from the conveyer belt 52. The plungers 56 have hemispherical friction heads. The plunger 56 furthest from the second conveyer 28, arrests a carton 12 as the preceding carton is being released by the second plunger 56 nearest the conveyer 28. When the released carton is clear of the second plunger 56 the first plunger 56 releases its carton which is then held by the second plunger in readiness for release to the second conveyer 28. As the cartons 12 move across the retaining means 76 to the dropping out position or aperture 78, the parallel track 82 is initially narrow enough at 86, Figs. 6 and 7, to lie between the inner flaps 22 and then widens at 88 to a substantial width which extends over the dropped inner flaps 22 which are partially supported by outer rails 80 and 84. When the central track 82 has widened to its full width to support the articles 14 within the inverted carton 12, the outer tracks 80 and 84 terminates at 90 and 92 to permit the inner flaps 22 to be raised to a substantially horizontal position by swept-back fins 94 and 96. A diverter 98 then guides the flaps 22 into inclined slots 100 and 102 provided by pairs of vertically spaced and inclined rails 104. As the cartons move up the inclined slots 100 and 102, the articles 14 slide to the edge of the drop-out plate 114 where they smoothly drop on to a third conveyer 30 when they reach the aperture or dropping position 78. The articles 14 are smoothly urged over the edge 115 of the plate 114 by the forward motion of a partition 16 or a wall of the carton 12 depending upon which portion of the carton 12 is at the back of the particular articles. The speeds of the third conveyer belt and positive drive means 69 of the second conveyer 28 are co-ordinated to prevent interference between rising cartons 12 and the articles 14 as they move off to their separate destinations. The dividing partitions 16 in the cartons 12 are maintained in position by a wedging action between pairs of inclined rails 104 horizontally spaced apart at a distance slightly less than the normal width of the cartons 12. Specification 574,683 is referred to.