Apparatus and method for controlling moving material and the like

A web handling apparatus configured to carry a moving web of indeterminate length through a path of travel, said apparatus comprising:

• a frame member configured to secure a web at a position inward from a longitudinal edge of said web;
• an adjustment device in operative association with one of said frame member and said web and configured to adjust the relative transverse position of said web and said frame member;
• a first detection device disposed upstream from a longitudinal position with respect to said frame member at which said web is secured by said frame member, said first detection device configured to monitor the transverse position of said web and to adjust, in association with said adjustment device, said relative position of said web and said frame member;
• and
• a second detection device disposed downstream from said longitudinal position, said second detection device configured to monitor said inward position and to adjust, in association with said first detection device, said inward position toward a desired position.

A tenter frame for moving a textile web of indeterminate length through a path of travel, said tenter frame comprising:

• a frame member having a driven endless element, said driven endless element supporting spaced apart plates having a securing mechanism for securing said textile web at a position inward from a longitudinal edge of said textile web;
• an adjustment device in operative association with said frame member and configured to adjust the relative transverse position of said textile web and said frame member;
• a first detection device disposed upstream from a longitudinal position with respect to said frame member at which said textile web is secured by said securing mechanism, said first detection device configured to monitor the position of said textile web edge and to adjust, in association with said adjustment device, said relative position of said textile web and said frame member;
• and
• a second detection device disposed downstream from said longitudinal position and relative to said plates so that the transverse position of said edge of said textile web at least in part determines whether said second detection device senses one of said plates and gaps between said plates, said second detection device configured to sense for said one of said plates and said gaps, to compare the number of said one of said plates and said gaps sensed by said second detection device to a number of said one of said plates and said gaps expected to be sensed were said textile web edge to remain at least approximately within a predetermined transverse position, and to adjust, in association with said first detection device, said inward position toward a desired position responsively to said comparison of said sensed number to said expected number.

A web handling apparatus configured to carry a moving web of indeterminate length through a path of travel, said apparatus comprising:

• a frame member including elements to secure a web at a position inward from a longitudinal edge of said web such that a waste area is defined from said edge through said inward position, said elements defining a repetitive characteristic that is distinguishable from said web and that occurs at predictable intervals with respect to a longitudinally stationary position proximate said elements;
• an adjustment device in operative association with said frame member and configured to adjust the relative transverse position of said web and said frame member;
• a first detection device disposed upstream from a longitudinal position with respect to said frame member at which said securing elements secure said web, said first detection device configured to monitor the transverse position of said web and to adjust, in association with said adjustment device, said relative position of said web and said frame member;
• and
• a second detection device downstream from said longitudinal position and configured to sense for said repetitive characteristic, to compare the number of said repetitive characteristics sensed by said second detection device to a number of said repetitive characteristics expected to be sensed were said edge to remain at least approximately within a predetermined transverse position, and to adjust, in association with said first detection device, said inward position to substantially achieve a desired said waste area.

A web handling apparatus configured to carry a moving web of indeterminate length through a path of travel, said apparatus comprising:

• a frame member configured to secure a web at a position inward from a longitudinal edge of said web;
• an adjustment device in operative association with one of said frame member and said web and configured to adjust the relative transverse position of said web and said frame member;
• a first detection device disposed upstream from a longitudinal position with respect to said frame member at which said web is secured by said frame member, said first detection device configured to monitor the transverse position of said web and to adjust, in association with said adjustment device, said relative position of said web and said frame member;
• and
• a second detection device disposed downstream from said longitudinal position, said second detection device configured to monitor the transverse position of said edge and to adjust, in association with said first detection device, said relative position of said web and said frame member to substantially achieve a desired said inward position.

A method for maintaining an edge of a moving web at a desired operating path, comprising the steps of:

• securing said web on a web handling apparatus having spaced apart elements;
• moving said web so that gaps between said spaced apart elements are intermittently obscured with respect to a detection position proximate said spaced apart elements depending upon the position of said edge with respect to a desired edge path;
• sensing for one of said gaps and said spaced apart elements with respect to said detection position;
• and
• initiating adjustment of said position of said web edge on said web handling apparatus toward said desired operating edge path responsively to whether said one of said gaps and said spaced apart elements is sensed with respect to said detection position.

A web handling apparatus configured to carry a moving web of indeterminate length through a path of travel, said apparatus comprising:

• a frame member configured to secure a web at a position inward from a longitudinal edge of said web and including spaced apart elements proximate a desired position of said web edge;
• a detection device in operative association with said frame member and configured to sense for one of said spaced apart elements and gaps between said spaced apart elements from a detection position situated so that the transverse position of said edge with respect to said desired edge position at least in part determines whether said detection device senses said one of said spaced apart elements and said gaps;
• and
• a web adjustment assembly in operative association with said detection device and configured to initiate adjustment of the relative position of said web edge and said frame member responsively to said detection device to achieve said desired position of said web edge.

A tenter frame for moving a textile web of indeterminate length through a path of travel, said tenter frame comprising:

• a frame defining a longitudinal path of travel of said web;
• a frame member disposed on said frame generally parallel to said path of travel and 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, said frame member having a driven endless element supporting spaced apart plates having a securing mechanism for securing said textile web at a position inward from a longitudinal edge of said textile web during passage of said material at least partially through the tenter frame;
• an adjustment device in operative association with said frame member and configured to adjust said frame member laterally with respect to said path of travel;
• a first detection device, said detection device including a detector housing disposed on said frame member upstream from said securing mechanism and proximate a normal operating path of travel of 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 sufficiently laterally offset therefrom to detect substantial lateral deviation of said edge from said normal operating path, said detector assembly being operatively associated with 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 predetermined rate and to bring about adjustment of the lateral position of said frame member 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, so that said security elements engage said material at said inward position;
• and
• a second detection device disposed on said frame member downstream from said front detection device and relative to said plates so that the transverse position of said edge of said textile web at least in part determines whether said second detection device senses one of said plates and said gaps between said plates, said second detection device configured to sense for said one of said plates and said gaps, to compare the number of said one of said plates and said gaps sensed by said second detection device to a number of said one of said plates and said gaps expected to be sensed were said textile web edge to remain at least approximately within a predetermined transverse position, and to adjust, in association with said first detection device, said inward position toward a desired position responsively to said comparison of said sensed number to said expected number.