GB829928A - Devices for feeding sheets to calender and the like machines - Google Patents

Abstract

829,928. Ironing-machine feed. WOMERSLEY, A. E., and KELLETT, H. April 14, 1958 [April 18, 1957], No. 12636/57. Class 138 (2). [Also in Group XVI] A sheet of rectangular material to be fed towards rolls 11 of e.g. an ironing or calendering machine, is placed over the framework of Fig. 1 with the extremes of its leading edge in clamps 2 slidable along a bar 4 of the frame 8 which is pivoted at 10 and normally biased to the position shown by a weight 5. An hydraulically operated piston 44 acts upon a pivoted bar 40 to move the carriage 30 along bar 32 (towards the left in Figs. 1 and 2) and actuate pivoted parallel linkages 26, 28 so as to separate the clamps 2 until the material leading edge is taut. At this stage separation of the clamps ceases, and continued movement of carriage 30 tilts the frame 8 forwardly about pivots 10 to present the leading edge, which is slightly proud of the front edges of the clamps, to the bight between the rolls 11. The weight of material when placed in position actuates micro-switches 50 and 52 (not shown) in the clamps, to close an electric circuit (Fig. 5, not shown) and open valves which admit pressure fluid to cylinders 24 to close the jaws 14, 16 and grip the sheet. Simultaneously a further valve is opened to admit fluid to the cylinder 46 to cause piston 44 to move inwardly and actuate the carriage 30 &c. At the end of its forward pivotal movement the frame 8 actuates a switch element 61 to interrupt the fluid supply to cylinder 46, whilst another switch element 63 also closes to interrupt the supply to cylinders 24 thus opening clamps 2 and permitting feed of the sheet. When the trailing edge of the sheet passes over switch 50 the latter returns to its normal position, and since switch element 63 is closed fluid is now admitted to the opposite end of cylinder 46 to move the piston 44 outwardly to restore the carriage 30 &c. to the position of Fig. 1, and the switch elements 61, 63 to their normal positions. Registration control.-The sheet is maintained straight and parallel to the rolls 11 by a photoelectric cell and a light source provided in each clamp, between which the side edge of the sheet must pass. If the sheet is displaced to expose the cell to the source a solenoid-controlled valve in the pressure fluid circuit operates an hydraulic motor 70 coaxial with and driving a tensioned roller 72 over which the sheet is draped. The transverse force exerted on the sheet by the rotation of roller 72 re-aligns the sheet. The edge of the sheet also now intercepts the light from the source and motor 70 stops.