GB439362A - Web tensioning mechanism for printing and other machines - Google Patents

Abstract

439,362. Feeding webs. HOE & CO., Ltd., R., 109, Borough Road, London.- (Hoe & Co., Inc., R.; 138th Street, New York, U.S.A.) June 6, 1934, No. 16849. [Class 100 (i)] A web supply mechanism for a printing or other machine is provided with means for rotatably supporting a number of rolls, a brake device, and means operating automatically in dependence upon the speed of the rolls, to establish braking association between the brake device and that roll which is rotating at the highest speed. In the web renewing operation of the machine, the brake is thus automatically transferred to the new roll when the webs are joined together and the old web severed. In one form, Figs. 1 and 7, active and reserve rolls A, B are carried by arms 14, 15 adjustable according to the width of the rolls, upon a pair of parallel shafts 18, 19 secured at their ends to members 75, 76 having trunnions engaging bearings or pedestals 11, 12. A worm-wheel 84 secured to one trunnion is adapted to be driven by a motor to bring the rolls successively into the feeding position. The shafts 18, 19 are connected centrally by a cross-piece 21 which also forms a bearing for one end of a shaft 89 which passes centrally through the arm 15, member 76 and its trunnion and is connected by a coupling 91 to a brake E. Within the arm 15 the shaft 89 carries two sprocket wheels 95, 96 connected by chains 118, 119 to sprocket wheels 68 associated with the spindles 38 of the rolls. Each sprocket wheel 68 is secured by a plate 62, Fig. 5, and screws 32, 69 to a sleeve 31 mounted on roller bearings 27<1> in a housing 27 on the end of the arm 15. The spindle 38 is formed with portions 46 .. 49 of different diameters, portions 47 and 49 carrying roller and ball bearings 41, 42 respectively and portion 46 engaging in a disc 33 secured to the sleeve 31 and provided with a fibre washer 35 to prevent leakage of oil from the bearings. The portion 48 has secured to it a disc 51, Fig. 6, having notches 52 containing spring-pressed rollers 53 engaging the inner surface of a flange 39 on the sleeve 31. As the spindle 38 of the active roll is rotated by the unwinding roll thereon, it drives the sleeve 31 and sprocket 68 through the clutch 51, 53 and is thus operatively connected to the brake. The sleeve 31 of the spindle of the reserve roll B is at the same time driven by its sprocket wheel 68 but rotates idly without driving its spindle 38. When, however, the roll B is brought up to web speed, attached to the old web, and the old web severed, its spindle 37 automatically drives its sprocket wheel 68 to connect it to the brake. In another form, the roll supporting arms are carried by a single central shaft instead of a pair of spaced shafts and the brake E is adapted to be applied to the spindles at both ends of the active roll. These spindles, which are constructed substantially as shown in Figs. 5 and 6, are connected by sprocket wheels and chains to sprocket wheels on a shaft which is supported from and parallel to the shaft carrying the roll supporting arms and is connected by gearing to the brake. In both forms the pedestal 12 is adjustable on a base 13 for side register of the web by a motor 112 driving through gears 113, 114, 115, a screw 116 threaded through a projection 117 on the base 13. Specifications 385,037 and 417,499 are referred to.