GB1283963A - Accumulation conveyor - Google Patents

Abstract

1283963 Roller conveyers LOGAN CO 30 July 1969 [30 July 1968 31 Oct 1968] 38321/69 Heading B8A An accumulation conveyer includes rollers 18 which, due to compression springs (58), Fig. 6 (not shown), normally press an endless belt 16 into driving engagement with carrying rollers 14 but which, by means of inflatable air hoses 66, may be lowered such that there is only light frictional engagement between the belt and the rollers 14. A pivotable stop roller 8 controls the hose air supply and, by providing a series of check valves in the hoses 66, the lowering of the rollers 18 at the downstream end of the conveyer is greater than that at the upstream end. Accordingly, between the upstream and the downstream ends there will be a progressive reduction in the driving force exerted on articles A. The articles are released by actuating a cylinder 116 connected to the mounting of the stop roller 8 and by deflating the hoses 66. The roller 8 is raised in response to the operation of a photo-cell device downstream of the roller when an article is stopped for longer than a predetermined minimum period. The roles of the springs (58) and of the hoses 66 may be reversed, i.e. the hoses may be deflated to cause the rollers 18 to be lowered. In a modification, Fig. 11, control of air pressure to sections of hose 206 for lowering pairs of pressure rollers 192 is provided by sensor rollers 194 normally raised above the plane of carrying rollers 182. When a sensor roller 194 is depressed a valve 202 is actuated by an extended axle 196 of the roller and the associated pair of rollers 192 is lowered. Momentary depression of a sensor roller 194 is insufficient to cause lowering of the rollers 192. In a further modification, Figs. 17-19 (not shown), pressure rollers (302) are individually supported by pairs of air tubes (306) under the control of sensor rollers (314).