Apparatus for the longitudinal stretching continuous films or layers or to their longitudinal and transverse drawing simultaneous

摘要

1,004,563. Film stretching apparatus. SHELL INTERNATIONALE RESEARCH MAATSCHAPPIJ N.V. March 21, 1962 [March 23, 1961], No. 10854/62. Drawings to Specification. Heading B5B. An apparatus for the continuous longitudinal stretching of a web of a stretchable material, such as a film, or for simultaneous longitudinal and lateral stretching thereof, comprises an endless movable chain on each side of the path of longitudinal stretch, the chains comprising links of equal length that are mutually hingeably connected, grippers for gripping the adjacent edge of the web connected to alternate hinge connections of each chain, and guide channels, grouped in pairs on each side of the path of stretch, the guide channels of each pair nearest the path of stretch guiding the chain hinge connections to which the grippers are connected, and the other guide channel of the pair, which converges towards the first in the direction of travel of the web, guiding the chain hinge connections without grippers over at least a part of the path traversed by the chain being guided by this pair of guide channels, whereby in operation of the chains the spacing between adjacent grippers of at least some of the grippers which are in engagement with the web increases as these grippers carry the web forward. The pairs of guide channels may diverge in the direction of travel of the web to provide lateral stretching also and the amount of divergence may be adjustable according to the degree of lateral stretching to be effected. The degree of convergence of the guide channels of each pair may be adjustable in order to make the degree of longitudinal stretching adjustable.