| 摘要 |
819,979. Making paper bags. RAWE, M. April 3, 1957 [April 5, 1956], No. 10954/57. Class 94(2). In apparatus for producing cross-bottoms in paper tubes in the manufacture of paper bags, the flattened paper tubes 53 are opened by suckers 1 arranged for movement towards and away from each other, each sucker being carried by a suction tube 35 normally closed by a valve 36 located close to the sucker, and control means is provided to effect simultaneous opening of the valves 36 at the instant when the suckers engage a paper tube. As shown, each sucker 1 is adjustable on the tube 35, and the latter is secured to a hollow suction shaft 47 rotatable about a stationary hollow shaft 50 and driven by bevel gears 51, 52. The valve 36 has a stem 37 supported for axial movement in bushes 38, 39, and a nut 40 which is screwed on to the tube 35. A compression spring 42 is arranged between the nut 40 and a flange 41 secured on the end of the stem 37 to hold the valve 36 on its seating. A collar 43 secured to the stem 37 carries a roller 45 which, when the tube 35 is rotated, engages a stationary adjustable cam 48 which therefore controls the opening of the valve 36. In a modification, the valve stems may be moved axially to open the valves 36 by electromagnets controlled by the rotating shafts 47. |
