GB190929377A - Means for Governing the Position of the most Advanced Sheet of a Pile or Bank of Paper in Sheet Feeding Apparatus. - Google Patents

Abstract

29,377. Vickery, F. W. Dec. 15. [Cognate Application, 14,386/10.] Feeding sheets. - Relates to means, in sheetfeeding apparatus feeding from a fanned-out pile, for correctly positioning the most advanced sheet, preparatory to its being taken by the separating- devices. The pile of sheets is supported on a table 4 over which passes a series of tapes 21 stretched between rollers 19, 20, the former of which is intermittently fed to advance the pile by a pawl 14, on an arm 13 on the rock-shaft 6, which engages a ratchet-wheel 17 fast on the roller 19. The shaft 6 carries also a bell-crank 7 one arm of which engages a cam 8 on the main shaft 9, while the other carries a pawl 2, adapted to engage a ratchet rack 3 beneath the feed table. A second cam 23 on the shaft 9 operates a foot 28 to hold the front sheet still upon the table 4. In operation, as soon as the nose 34 of the cam 8 passes clear of the roller on the bell-crank 7 a spring 11 rocks the arm 13 to the right, carrying the finger 10 on the pawl 2 up to the edge of the front sheet held on the table 4. When contact occurs, the pawl 2, which is counterbalanced, is rocked to engage the rack 3 and thus arrest the motion of the arm 13. The number of teeth of the ratchet-wheel 17 embraced by the pawl 14 and in consequence the subsequent feed of the pile is thus determined by the position of the sheet. The foot 28 having been raised by the cam 23, the arm 13 is returned by the cam 8, rotating the roller 19 and carrying the finger 10 forward just in advance of the sheet. The front sheet having thus been fed forward to a predetermined point, the feeding - mechanism operates to separate the sheet from the pile and convey it to the printing or other machine. For feeding larger sheets the apparatus described may be duplicated, each set being arranged to operate independently. A blast of air may be employed instead of the foot 28 to hold the edge of the top sheet flat. In a further modification employing two sets of independently-operated mechanism, means are provided for squaring the top sheet before the pile is fed forward by the conveyer bands. This is accomplished by providing each of the levers 5 with a roller or jaw gripping- device adapted to seize the edge of the most advanced sheet and square it, the foot 28 being raised for the purpose. In operation, should one side of the sheet be advanced less than the other, the corresponding lever 5 moves farther forward before it is arrested by the pawl 2. The operating cams being exactly similar, the lever 5 which has advanced farthest is first engaged by its cam and alined with the other arm before the two start moving together. After the front sheet has been positioned, the table 4 may be lifted to assist in presenting the sheet to the conveying-rollers 31.