Apparatus and method for securing a moving fabric

Apparatus for handling a moving material of indeterminate length, comprising:

• a material moving mechanism for moving said material along a longitudinal path of travel with respect to said apparatus;
• an adjustment device configured to laterally adjust said moving mechanism with respect to said edge of said material;
• and
• a detector assembly located adjacent a normal operating path of travel of said edge, said detector assembly configured to detect lateral deviation of said edge from said normal operating path and being operatively associated with said adjustment device to bring about adjustment of said moving mechanism relative to said edge of said material in reaction to deviation of said edge from said normal operating path, the rate of said adjustment being dependent upon time said edge remains out of said normal operating path.

Apparatus for handling a moving material of indeterminate length, comprising:

• a material moving mechanism for moving said material along a longitudinal path of travel with respect to said apparatus;
• an adjustment device configured to laterally adjust said moving mechanism with respect to said edge of said material;
• and
• a detector assembly located adjacent a normal operating path of travel of said edge, said detector assembly configured to detect lateral deviation of said edge from said normal operating path and being operatively associated with said adjustment device to bring about adjustment of said moving mechanism relative to said edge of said material in reaction to deviation of said edge from said normal operating path, the rate of said adjustment being dependent upon time said edge remains out of said normal operating path and wherein said detector assembly is configured to recognize a lateral deviation of said edge from said normal operating path when said edge fails to cross over a line within said normal operating path within a predetermined time period.

Apparatus for handling a moving material of indeterminate length, comprising:

• a material moving mechanism for moving said material along a longitudinal path of travel with respect to the apparatus;
• an adjustment device configured to laterally adjust said moving mechanism with respect to said edge of said material;
• and
• a detector assembly located adjacent a normal operating path of travel of said edge, said detector assembly including a detector housing including at least one control detector disposed adjacent said normal operating path to detect lateral deviations of said edge from said normal operating path and an emergency detector sufficiently laterally offset from said control detector to detect substantial lateral deviation of said edge from said normal operating path, wherein said detector assembly is operatively associated with said adjustment device to bring about adjustment of said moving mechanism relative to said edge of said material, in reaction to deviation of said edge less than said substantial deviation, at a rate dependent upon time said edge remains out of said normal operating path and to bring about adjustment of said moving mechanism relative to said edge of said material, in reaction to said substantial deviation, at an emergency speed, said emergency speed being greater than said rate of adjustment in reaction to deviation less than said substantial deviation.

A tenter frame for handling a moving material of indeterminate length, comprising:

• a frame defining a longitudinal path of travel of said material;
• a pair of frame members, each said frame member disposed on said frame on a respective side of, and generally parallel to, said path of travel and being pivotally mounted to said frame at a downstream end of said frame member so that said frame member may be adjusted laterally with respect to said path of travel;
• a pair of driven endless elements, each said endless element being at least partially received by a respective said frame member and having securing elements disposed thereon for engaging and holding said material during passage of said material at least partially through the tenter frame;
• a pair of adjustment devices, each said adjustment device operatively associated with a respective said frame member to adjust said frame member laterally with respect to said path of travel;
• and
• a pair of detector assemblies, each said detector assembly including a detector housing disposed on a respective said frame member, so that said detector housing moves with said frame member, upstream from said securing elements and adjacent a normal operating path of travel a said edge, said detector housing including a control detector configured to detect lateral deviation of said edge from said normal operating path and an emergency detector upstream from said control detector and sufficiently laterally offset therefrom to detect substantial lateral deviation of said edge from said normal operating path, each said detector assembly being operatively associated with a respective said adjustment device to bring about adjustment of the lateral position of said frame member in reaction to deviation of said edge less than said substantial deviation at a rate dependent upon time said edge remains out of said normal operating path, and to bring about adjustment of the lateral position of said frame member in reaction to said substantial deviation of said edge from said normal operating path of said edge at an emergency speed, said emergency speed being greater than said rate of adjustment in reaction to deviation less than said substantial deviation, so that said securing elements engage said material within a desired position adjacent said edge.