GB1315492A - Removal of sheet material from products - Google Patents

Abstract

1315492 Pneumatic separation CHARCON PRODUCTS Ltd 18 May 1970 [17 May 1969] 25275/69 Heading B2H Sheet material, e.g. filter paper 5, Figs. 1 and 2, adhered to a surface of an article, e.g. a pressed concrete slab 6, is removed by directing a stream of air towards an edge of the sheet in a plane parallel or substantially parallel to, and level with, the plane of the surface at that edge, the velocity of the air stream being sufficient to blow the sheet clear of the article. As shown, the air is supplied through nozzles 8 connected by branch pipes 9 to a common air supply conduit to which compressed air is fed via a control valve (11), Fig. 4 (not shown), the operation of which is controlled by a linear cam (12). The cam may have a two-stage profile whereby at first partial opening of the valve provides a relatively gentle air stream sufficient to curl up the edge of the paper adjacent the nozzles, and thereafter complete opening of the valve provides a high velocity air stream which blows the curled up paper clear of the slab. The nozzles are preferably mounted for vertical horizontal and relative angular adjustment in any plane. In Fig. 9, two sets of nozzles 8a, 8b are used in conjunction with a pressing mould 20 and a slab transfer apparatus to remove filter paper respectively from the bottom and top of a concrete slab 23. The slab 23 is lifted from the mould 20 by a vacuum pad 24 carried by a wheeled trolley 25 which runs on an overhead track 26. The trolley carries the slab past the nozzles 8a to remove the filter paper from its underside. The slab is then transferred to a pivotable arm 22 and nozzles 8b serve -to remove the filter paper from the top of the slab. The arm 22 is then pivoted at 28 to transfer the slab to a delivery station 29. The trolley carries two cams 30, 31 arranged to actuate pilot valves through one-way switches 32 and 33. The pilot valves actuate a main type 3-way air valve controlling air supply to the two sets of nozzles 8a and 8b. The cam 30 actuates the switch 32 when the trolley moves from right to left and the cam 31 actuates the switch 33 when the trolley moves from left to right.