| 摘要 |
A method and apparatus are disclosed for forming a vent hole in an end closure in the form of a twisted plait on a hose-type packing wrapper, especially a sausage skin, shirred to form a caterpillar with an unshirred wrapper section (34). A first elongated winding element (46) is introduced into the packing wrapper 940) to behind the first shirring folds. Subsequently, the unshirred wrapper section (34) is seized along an axial surface line by a second elongated winding element (48) of a length shorter than that of the first winding element (46) which is moved radially towards the latter. Thereupon, the winding elements (46, 48) are actuated in rotating manner and, at the same time, are axially advanced. The twisted plait is thus generated from the free end of the winding elements (46, 48) in a manner progressing to the rear. At the end, by retraction of the winding elements (46, 48), a vent channel or hole remains in the twisted plait.
|
