GB136449A - Improvements in or relating to Web-roll Mechanisms for Printing Presses or other Web Machines. - Google Patents

Abstract

136,449. Goss Printing Press Co., (Goss Printing Press Co.). April 30, 1919. Feeding webs. - A web-roll changing mechanism for a printing or other machine comprises means for supporting two webrolls in fixed positions for alternative use, means for rotating a fresh roll in either position at the same surface speed as the running web, and manuallyoperated lever mechanism for operatively connecting the rollrotating means with the fresh roll and simultaneously pressing the end of the web from the fresh roll into contact with the running web to join the webs together. As shown, two web rolls 12, 13 are mounted in fixed bearings in a frame 10 beneath the press-room. The web 18 from the roll 12 in use passes round guiderollers 19, 20 and between a pair of rollers 21, 26, which are normally spaced apart, to the press 11. The rollers 20, 21 are geared together and are driven frictionally by the web. The web from the reserve roll 13 is prepared for the joining operation by passing it round guide and tensioning rollers 23, 24, and a roller 25 similar to the roller 20 and between the rollers 26, 21, as shown in Fig. 3. To lead the web into this position, its end is lightly attached to tapes 42 which pass' round the rollers 24, 25 and are attached to spring rollers 43, 44. The spring of the roller 44 is stronger than that of the roller 43, so that when the roll 13 is turned by hand, the tapes wind on to the roller 44, carrying the web into the bite of rollers 25, 26. The roller 26 is then given a partial rotation to carry the web into the position shown in Fig. 3, by the depression of a pedal 62, which acts through link 63 and lever 64 to raise a rack-bar 54 meshing with a segmental link 56 loose on the shaft 53. The gear 56 carries a drum provided with a, pawl engaging a ratchet-wheel fixed to the shaft 53. The pedal 62 is also connected to a similar mechanism for turning the roller 21, but the ratchet connexion of the gears with the roller shafts permits overrunning, so that the roller 21 rotates freely under the pull of the web 18. The new web is stripped from the tapes 42 by fixed guides 47. The tapes are rewound on to the roller 43 by means of a cord 45. Similar tapes 48 extending between spring rollers 49, 50 are provided to feed a new web from the upper roll into position. A rollrotating belt 27 extends round a sheave 28 loose upon a. sha.ft 29, and a sheave 30 carried by arms 32 fixed to the shaft 29, which is connected by an arm 41 and link 40 to a hand-lever 39 by which the belts can be moved to engage a roll in either position. The belts 27 are driven continuously from the press by a shaft 38 geared to the sheave 28. The arm 41 is connected by a link 69 to an arm 70 fixed to a shaft 71, to which are secured arms 72 carrying a glue or paste pot 73 in which is a pasting-roller 74 provided with scrapers 75, 76. The shaft 71 is connected by gears 77, 78 to a shaft 79 on which are eccentrics 80 connected by links 81 to eccentrics 82, 83 mounted in the frame 10 and carrying the shafts 53, 57 of the rollers 26, 21. With the new web in position, when the web 18 is nearly exhausted, the hand-lever 39 is operated to move the belts 27 into contact with the roll 13, and simultaneously the paste-pot 73 and roller 74 are moved into contact with the web 18 passing round the roller 21 to apply paste to the web, and the eccentrics 80, 82, 83 are operated to press the rollers 21, 26 together to adhere the webs together. The old web is then severed by a knife 84 carried by a shaft 85a within the roller 21 and normally held in an inoperative position by a spring 86, but adapted to be pressed outwards by a cam 87 operated by an arm 89 engaging a collar on the shaft of the pasting-roller 74. A similar knife is provided in connexion with the roller 26. In a modification, the old web is severed by a pivoted knife external to the rollers 21, 26 and operated manually by cords.