Patent GB-1387297-A (GB)
Title: Apparatus for transferring articles between a conveyor and a stack
IPC: B65H29/50
Filed: 1972-06-13
Abstract: 1387297 Stacking and unstacking articles; feeding and delivering sheets G BARGSTEDT 13 June 1972 [15 June 1971] 27599/72 Headings B8C and B8R Apparatus for stacking or unstacking articles by the transfer of articles between a conveyer disposed at a predetermined level and a stack of progressively varying height, comprises a rocker arm assembly carrying article gripping means, first driving means for pivoting the rocker arm assembly through substantially 180 degrees about a pivot axis having a reference level depending on the vertical height of the stack above the conveyer, second driving means co-operating with said first driving means for vertically moving the pivot axis of the rocker arm assembly during said pivotal movement, and means for automatic progressive adjustment of the vertical position of the pivot axis reference level for each successive transfer operation. As shown, two columns 3, 4 are provided beside a support comprising a roller conveyer 1 and bearing plates 5, 6 are movable vertically on the columns on rollers 7-10 and 13, 14. The plates 5, 6 are provided with pivot bearings 16, 17 for a rocker arm assembly comprising rocker arms 18, 19 which are interconnected by a beam 20 and carry vacuum cups 21, 22. A shaft 23 is rotatably mounted in plates 5, 6 and carries pinions 24, 25 which mesh with racks 26, 27 on the columns 3, 4. A stub shaft 28 extending through the bearing 17 is rotatably mounted in a gear housing 29 in which a bevel gear 31 is slidably and non-rotatably mounted on a square shaft 32 parallel to column 4. A torque transmitting member 33 is connected through a swivel member 34 to the gear 31 for rotating the gear and the shaft 32. The member 33 comprises rollers 35-38 which bear on the shaft 32. The shaft 32 is journalled in a bearing 39 and carries a pinion 40 in mesh with a rack 41 which is pivoted on a pin 43 in a head 44 which is slidable on a cross-beam 15. A rod 45 is also connected to the pin 43 and to a pin 46 of a crank 47 which is pivotal through 180 degrees by means of a motor driven sprocket 50. A double crank 53 carried by the drive-shaft of the sprocket 50 carries a motor-driven screw 55 which is operated in dependence upon the height of the stack to move a nut 57 from the end 58 as the stack decreases in height. During pivotal movement of the crank, the end 58 moves along an arc 61. A chain 62 extends over a sprocket 59 on the nut 57 to a fastening 63 and extends through the head 44 to a vertically movable cylinder-piston unit 71 which is adjustable vertically by a hand wheel 75. The arrangement is such that the vacuum cups move along a line 78. The rocker arm assembly is balanced by a counterweight assembly 88, 89, 93. In another arrangement, Figs. 8, 9, a double crank 99 is now rotatably connected to the pivot bearing or rocking shaft 98, and a motor driven pinion 101 at the end of the rocker arm assembly 94 and meshes with a rack 100 and with a rack 103 pivoted to a column of the frame. In another arrangement, Fig. 10, the vertical drive is effected in dependence on rotation of shaft 98.