| 摘要 |
823,346. Making paper &c. bags. WINDMOLLER, A., and GENNERICH, M. [trading as WINDMOLLER & HOLSCHER]. July 17, 1957 [July 27, 1956], No. 22641/57. Class 94(2). In a method of opening out the lateral folds in the manufacture of block-bottom bags by means of pairs of grippers on a bottom-making cylinder and an opening roller, the following piece of tube is additionally accelerated in the feed direction during the opening, so that the transverse crease is raised into the plane of the bottom which is being formed. The folded tube 5, Fig. 3, is held on the cylinder 1 and roller 6 and the folds opened out by grippers 2, 3, 7. The transverse crease 10, 11 is raised into the plane of the bottom by a rod 18 mounted in the cylinder and actuated by a stationary cam 27 to accelerate the tube during the opening. The rod may be actuated from the roller 6, or one rod from each side. In another form, Fig. 4, the acceleration is produced by a pair of roller members 29, 30 rotated by a belt 49 and intermittently actuated by a rotating cam 45 to cooperate with freely rotatable segmental discs 31, 32, whereafter the discs are restored against stops 35, 36 by tension springs 33, 34. The duration of the acceleration is adjustable by a circumferentially settable member 40. Solid discs may be used instead of segmental discs. |
