GB575897A - Improvements in or relating to web-guiding apparatus - Google Patents

Abstract

575,897. Feeding webs. FARRINGTON, G. H. Oct. 20, 1943, No. 17263. [Class 100 (i)] [Also in Group XXIX] Apparatus for maintaining side register of a travelling web comprises a pair of rollers, bars, or other members having straight line' web bearing surfaces, movable together in parallelism from a normal position at right angles to the path of the web between them to other angular positions the total length of the path of the web being unchanged. In one form, Fig. 3, the web passes over four rollers 1 ... 4, the rollers 1, 4 being mounted in fixed bearings on frames 7, 8 and the rollers 2, 3 being mounted on fixed self-aligning bearings 12, 13 at one end and, at the other end, in bearings 15, 17 in links 14, 16 pivoted about the axes of the rollers 1, 4 and connected by a link 18 for parallel movement. An arm 19 of the link 16 is operable by screw and nut mechanism 21, 22, 23 to adjust the angularity of the rollers 2, 3 if the web wanders thus causing a lateral movement of the web in the reverse direction to restore the register. In a modification, Fig. 4, two sets of four rollers 1 ... 4, 1A ... 4A are provided, the rollers 1, 4, 1A, 4A being in fixed bearings, and the rollers 2, 3, 2A, 3A being mounted in fixed bearings at one end and, at the other end, the rollers 2, 3A are mounted in bearings in links 14, 16A pivoted on the axes of the rollers 1, 4A and all the rollers 2, 3, 2A, 3A, are mounted in bearings in a link 18 connected to a pneumatic cylinder 27. The flow of air to and from the cylinder 27 is controlled by a valve 34 actuated by a lever 33 and a longitudinally movable shaft 30 carrying a pair of discs 28, 29 engaging the edges of the web. Movement of the web to either side actuates the shaft 30 to cause operation of the cylinder 27 to effect a web restoring movement to the rollers 2, 3, 2A, 3A. The cylinder 27 is actuated by a fluid pressure device as described in Specification 575,899, [Group XXIX], in accordance with variations in pressure set up in the supply line 36 by movements of the valve 34 which is shown in detail in Fig. 5. The spindle 39 which is acted upon by the lever 33 Fig. 4, and a returning spring 44, bears against a lever 43 pivoted to one arm of a bell crank lever 45 adjustable by a screw 47 and spring 48 to raise or lower the fulcrum of the lever 43. This lever is connected by a link 49 to a lever 50 pivoted to a bracket 46 and carrying an adjustable knife edge fulcrum 51 the edge of which lies in the plane of the pivot connections at both ends of the lever 50. A lever 53 rests on the fulcrum and is pivoted at one end to an arm of a bell crank lever 54 adjustable by a screw 55 and spring 57 to raise or lower the pivot of the lever 53. A piston valve 59 held against the lever 53 by a spring 60 controls the flow of pressure air from a supply pipe 63 to the pipe 61 connected to the pipe line 36, Fig. 4, the pipe 62 being connected to the atmosphere. Through the working range of the valve 59, the pressure in the pipe 61 varies directly as the movement of the valve 59 which is proportional to the movement of the spindle 39.