Patent GB-895415-A (GB)
Title: Positioning and splicing apparatus and process for positioning and splicing webs
IPC: B21C47/24
Filed: 1959-05-29
Abstract: 895,415. Welding by pressure; jointing. AEROPROJECTS Inc. May 29, 1959 [July 10, 1958; March 25, 1959], No. 18401/59. Class 83 (4). [Also in Groups XIII, XVI and XL (b)] In apparatus for splicing webs of metal foil or other material by welding or other means, a web is positioned by means comprising a pair of spaced concentric perforated tubes. The invention is described as applied to the positioning and splicing of a web of aluminium foil which is held in position on perforated feed rollers by suction. One such roller, Fig. 1, comprises spaced perforated concentric tubes 13, 15, the inner tube being connected to suction. Alternatively the outer tube 18 may be in contact with the inner tube 34 which is perforated over only a part of its periphery to provide a valve action. As shown in Fig. 3, two such rollers 18, 20 are supported between hollow end members 24, 26 with a plain anvil roll 22 between them but offset from their line of centres. The end members are carried between walls 12 and 14 by a trunnion axially aligned with the roller 18 and the outer tubes of rollers 18, 20 are rotatable through chain and sprocket gearing, the inner tubes being fixed. The manner in which the device may be used to join the ends of two webs is shown in Figs. 7-9. The rear end of web 46a is taken round anvil roller 22 and anchored on roller 20 by suction and the forward end of web 46b is anchored round roller 18. End supports 24, 26 are then rotated so that the webs are superimposed around the anvil, Fig. 8, and are welded together by a vibrating welder 47 or otherwise joined as by an adhesive or by crimping. The source of vacuum is then cut off and the device turned back to the idle position, Fig. 9, and the ends 46a, 46b beyond the join are cut off and the web is free to run between the idler rollers 48, 50. The welder may operate at 50,000 cycles per second with a clamping force of from one to twenty pounds and a power level of 15 to 150 watts. Seaming may be at a speed of up to 200 inches per minute. The method of splicing double ply or pack foil is shown in Figs. 13 and 14. The trailing ends of one web are held on suction rollers 51, 51a and the webs united over idle roller 53, while the leading ends of the other web are divided at idle rollers 54 and taken over the same rollers 51, 51a and then held around suction rollers 55, 55a. The webs are joined by welding heads 57, 57a, using the suction rollers 51, 51a as anvils. Similarly suction rollers could be used as anvils instead of rollers 22 when splicing webs of single ply foil. Figs. 19 and 20 show the form of frame used to support the rollers and the welding heads. The rollers 51, 51a and idler roller 54 are supported by an arm 76 and driven by chains and sprockets from a motor 154 and gear-box 156. A cam wheel 184 with a series of circumferential notches 184a is driven by the same chain and cooperates with the plunger of a switch 188 to ensure that the welding heads can operate only when an unperforated part of the roller surface is presented to them. Rollers 55 and 55a and idler 53 are mounted on another arm 72 of the frame. Hoses 298 and 300 connect the suction rollers to pumps 292 and 294 on the base 296 of the frame. Each of the rollers 51, 51a comprises a perforated inner tube 65, Fig. 21, one end being supported in a collar 58 bolted to the frame and being connected to a suction pipe 85 while the other end is closed by a plug 71 from which extends a rod 75. An outer tube 79 with perforations arranged in circumferentially spaced longitudinal rows is rotatably mounted on the tube 65 by bearings 98, 102. Surrounding the rod 75 is a sleeve 114 carrying a sprocket wheel 142 with a drive pin 144 which may be engaged within a hole 148 of a bushing assembly 100 inside the tube 79 by sliding the sleeve axially by means of a piston 126. Each of the rollers 55, Fig. 22, comprises inner and outer perforated tubes 83, 87, the outer tube being rotatable by a sprocket 234 on a rod 206 mounted in the frame arm 72. Each welding head 57 comprises a mounting bracket 264 slidable along a guide shaft 63 by worm and nut mechanism (not shown) and a welding tip carrier 268 pivoted to the bracket 264. On the carrier is a photo-electric control device 276 comprising a light source and a photo-cell connected so as to prevent the operation of the welding tip unless it receives light reflected from a web. Although the invention is described as applied to the joining of metal foil by welding it may also be used for positioning webs of metal, paper, plastic, cloth for other purposes and also for joining webs by adhesives or by crimping. Specification 895,414 is referred to.