| 摘要 |
A supply source of continuous elastic web and a support for the fixing of elastic elements are provided. On the support, which is normally constituted by a rotary drum, there are located at least one clamping element fixed to the support itself and a further clamping element which is movable relative to the fixed element between first and second positions. The distance between the fixed element and the movable element in the second position is less than the distance between the two elements in the first position and is substantially equal to the length of the tensioned elastic elements which it is desired to form. The free end of the continuous elastic web is clamped in the movable clamping element when this element is in its first position. There is thus produced, simultaneously and substantially continuously: a relative movement between the supply source and the support in the direction of alignment of the clamping elements so as to cause the supply of the continuous web to the fixed clamping element; the translational movement of the movable clamping element from its first position to its second position at a velocity less than the velocity of the movement between the web supply source and the support, and the supply of the web from the source at a velocity less than the difference between the velocity of the relative movement between the source and the support and the velocity of the translation of the clamping element between the first and second positions. When the movable clamping element reaches the second position, the web is clamped by the fixed clamping element whereby a piece of web extends between the fixed clamping element and the movable clamping element in a state of longitudinal tension the degree of which is determined by the velocity difference and the supply velocity of the web. Finally, the web is cut in the region between the fixed clamping element and the supply source, so as to separate the said piece from the body of the web and define one of the tensioned elastic elements, and to form a new free end of the web iself.
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