GB749099A - Improvements in or relating to sheet separating machines - Google Patents

Abstract

749,099. Feeding sheets. BACKHOUSE, H. T. April 12, 1954 [April 14, 1953], No. 10745/54. Divided out of 749,067. Class 100(1). Sheet separators; faulty feed control devices.- In sheet-separating apparatus in which initially an edge portion of the top sheet is elevated from the pile, means including a feeler arranged to move downwardly through a position normally occupied by a raised portion of a sheet, is provided for detecting failure to elevate the sheet and then causing a warning device to be operated or the whole or part of the apparatus to be stopped. The invention is described as applied to the apparatus disclosed in Specification 741,226 wherein suction grippers, on a subframe which descends as the pile 20 is consumed, elevate and tauten the front edge 185 of the top sheet of the pile, and then present it to mechanical grippers 151 carried by upwardly moving chains. The sub-frame, which includes cross-bars 37, 38 and a driving shaft 66, carries two brackets 300 which support a trip shaft 302 drivingly connected to a vertical shaft at the side of the apparatus to cause, when the shaft 302 is rocked, the disconnection of a clutch in the drive to the apparatus. Two detecting devices are provided, each comprising a feeler finger 303 secured to a bracket 304 freely pivoted on the shaft 302 and urged clockwise by a spring 306, and a lever 308 also freely pivoted on the shaft 302 and having a roller 309 in contact with a cam 310 secured to the drive shaft 66. An abutment 312 on the lever 308 co-operates with an underface of the bracket 304 whereby the cam can lift the feeler 303, and a latch 314, pivoted on the lever, has a tail 315 engaging the underside of the feeler, and a hooked end adapted to co-operate with an arm 316 keyed to the shaft 302. In operation, the cam 310 raises the feeler 303 to position 303a, the sheet edge 185 is lifted and tautened, and the feeler is lowered under the action of gravity and the spring 306 so that its end can rest on the sheet. If there is no sheet present, the feeler swings down to position 303b and rocks the latch 314 so that it engages the arm 316; on continued rotation of the cam 310, the lever 308 is moved upwardly to rock the shaft 302 which disengages the main driving clutch and stops the apparatus. No re-setting of the feeler device is necessary after the apparatus is restarted. The cam 310 is slidable along the shaft 66, and the lever 308, bracket 304 and arm 316 are slidable along the shaft 302; the bracket 300 has fork arms 320, 321 engaging the shafts 66, 302, respectively, to facilitate the sliding. The invention may be used in combination with the means for detecting the separation of two superposed sheets described in Specification 749,067. Specification 427,041 also is referred to.