GB808214A - Methods of and apparatus for opening out folded paper - Google Patents

Abstract

808,214. Feeding sheets. HEPP, R. Nov. 15, 1955 [Nov. 18, 1954], No. 32595/55. Class 100(1) Opening devices for folded sheets &c.:- In a method of opening out a paper sheet or a group of superposed sheets folded so as to have two adjacent parallel edges of which one protrudes slightly in front of the other, the sheet is fed towards a stop travelling at a slower rate than the sheet and retained thereby while the two adjacent parallel edges are moved apart from one another. Fig. 9 illustrates the principle of the invention. The folded sheet S is fed over a support R so that the protruding edge engages a pocket 5 on a rotating roller &c 4. The speed of the pocket 5 is less than that of the sheet, so that although at a postion to the right of the roller the lower leg of the sheet has proceeded along the support R and the upper leg is still engaging the pocket 5, eventually the upper leg will spring away from the pocket, and can then fall over some support or member which will keep the legs separated. The pocket 5 could be replaced by a gripper which is cam-actuated to grip and subsequently release the sheet, and the support R could be replaced by another roller provided with a suction aperture or sucker which grip the shorter leg of the sheet to assist opening: the roller 4 could also be provided with a sucker to hold the upper leg aaginst the roller. In the practical construction shown in Figs. 18 and 19, the cylindrical support 18 for the folded sheet S is rotatable in the direction 20, has a number of rollers 23 on its circumference on which the sheet is placed, and the rear folded edge of the sheet is engaged by a hook member 22. The sheet is held against the rollers 23 by a set of brushes 24 concentric with the support 18. The legs of the sheet are deflected and guided away from the support 18 by a member 29 so that the longer leg of the sheet engages in a pocket 26 in a roller 25 rotating in the direction 28. The peripheral speed of the pocket 26 is less than the speed of the sheet S, so that the shorter leg of the sheet passes to the right of a member 36, and the longer leg springs out of the pocket 26 and falls to the left of the member 36. The deflector 29 is secured to a sleeve 33 rotatably mounted on a fixed shaft 34, and has a roller 35 engaging the roller 25. A second member 32, secured to the sleeve 33, has a roller 31 engaging a cam 30 rotatable with the roller 25, so that the deflector 29 is lifted periodically towards the support 18 to intercept the legs of the sheet S and divert them to the roller 25. The sleeve is urged about the shaft 34 counterclockwise by a torsion spring. The roller 35 may be replaced by an endless conveyer band which bears on the roller 25. In a modification, a cam-operated gripper replaces the pocket 26 on the roller 25. The apparatus can include opposed sets of suction rollers for operation on folded sheets having no protruding edges, and the driving mechanism of the apparatus can include means for adjusting the setting of the pockets and the suction members relatively to each other and to the driving gears. Further, the driving gearing may include means for varying the speed of rotation of the roller &c. and for varying the speed of the rollers &c. during each paper unfolding cycle.