| 摘要 |
PCT No. PCT/CH95/00285 Sec. 371 Date Apr. 21, 1997 Sec. 102(e) Date Apr. 21, 1997 PCT Filed Dec. 1, 1995 PCT Pub. No. WO96/17720 PCT Pub. Date Jun. 13, 1996Two holders (27-30) arranged on both sides of the mid-plane (4) of a conveyed tubular bag (1) are rotated in parallel directions by crank mechanisms (15-18). A sealing jaw (37) or matching jaw (38) is vertically guided in the holders (27-30) and prestressed by a spring (41) against a stop (44). Stopping rollers (62) project sideways from the jaws (37, 38) and bump against supporting strips (48, 49) before the jaws (37, 38) touch each other. The supporting strips (48, 49) are moved against each other by a controller (54) in such a way that the vertical components of motion of the jaws are delayed in a controlled manner. On the contrary, before the jaws (37, 38) are moved away from each other, they are accelerated up to the required vertical speed to bump softly against the stop (44). This device works without noise, is gentle to the material and may be adapted to various working conditions. |
