Flexible dye tube

A tube for use on a perforated dyeing spindle, for supporting for dyeing a package of yarn wound therearound, the tube having a longitudinal axis and comprising a plurality of flexible uprights spaced circumferentially around the axis, top and bottom base portions of the tube, each upright being joined at opposite ends to the base portions, respectively, and a plurality of rings joining the uprights in spaced planes perpendicular to the axis, at least two of the rings being incomplete and having, respectively, gaps at circumferentially staggered positions so as to leave one pair of adjacent uprights free to approach each other in one of the planes and a second pair of adjacent uprights free to approach each other in a second of the planes, thereby providing the tube with balanced and limited radial flexibility to accommodate yarn shrinkage, the spaced uprights, base portions, and rings cooperatively defining a plurality of dye openings through the tube.

BACKGROUND OF THE INVENTION 
This invention relates to tubes for supporting for dyeing a package of yarn 
wound therearound, and provides an improvement in certain respects in the 
dye tubes disclosed in U.S. Pat. Nos. 3,448,597 and 3,882,698, both hereby 
incorporated by reference. 
SUMMARY OF THE INVENTION 
Shrinking after dyeing of polyester and other yarns produces great crushing 
forces on dye tubes, tending to break or permanently distort the tubes, 
preventing their reuse. 
The invention provides a simple, inexpensive, easy to manufacture and 
convenient to use dye tube capable of accommodating the crushing forces of 
shrinking yarns in repeated uses. The tube can be a one-piece 
construction. 
The invention allows minimization of the contact area between the yarn and 
the tube surfaces while maximizing dye saturation of the yarn, and also 
provides for uniform absorption of the dye without "cross-overs" or light 
colored spots on the yarn caused by undue pressure on dye tube surfaces. 
Furthermore the tubes can easily and quickly (and even automatically) be 
stacked around a dyeing spindle, well sealed to each other even during 
shrinking of the yarn, without requiring separate spacers between adjacent 
tubes, and without overly restricting axial flow of dye between the tubes 
and the spindle. The tubes can be removed easily from the spindle even 
after yarn shrinkage, and are suitable for use with automatic unloaders 
which tip the spindles and depend upon gravity for removal of the tubes. 
Finally, the tubes retain the yarn in orderly windings even after 
shrinkage, and are useful with yarns of many different physical 
characteristics. 
The tube disclosed in U.S. Pat. No. 3,448,597 did not have the flexibility 
to accommodate yarn shrinkage. The tube disclosed in U.S. Pat. No. 
3,882,698 was an improvement in that respect, but in use proved to be 
subject to permanent deformation (e.g., by twisting), making removal from 
the spindle difficult and limiting reuse. Efforts to strike a happy medium 
by using a single ring to join the uprights halfway between the tube ends 
were also unsuccessful. 
In general the invention features uprights joined by rings with gaps at 
circumferentially and axially staggered positions to accommodate yarn 
shrinkage while limiting excessive deformation of the tube. In preferred 
embodiments the gaps are located in an axially central plane and two other 
planes spaced symmetrically from the center, with one gap between each 
pair of adjacent uprights. 
Other advantages and features of the invention will be apparent from the 
description and drawings herein of a preferred embodiment thereof.

DESCRIPTION OF THE PREFERRED EMBODIMENT 
Dye tubes 10 made of polypropylene with talc added to minimize shrinkage 
are stacked end to end on perforated dye spindle 12, and include top and 
bottom imperforate base portions l4, 16 to which are joined six 1/2 inch 
wide axially extending uprights 18 circumferentially spaced 11/32 inches 
apart. 
Each base portion 14, 16 includes an annular end sealing surface 20, 22 of 
inside diameter 15/8 inch and of outside diameter 2 inches. Dye spindle l2 
has an outer diameter of of 1.315 inch. 
Base portion 14 is slightly longer than portion 16 and has four vertical 
lugs 40 spaced circumferentially around its inner surface, to give the 
tube an effective inner diameter at one end slightly larger than the outer 
diameter of spindle 12, thereby helping to align adjacent stacked tubes on 
spindle 12 with adjacent opposing surfaces 20, 22 in sealing relation to 
each other. Lugs 40 are tapered at ends 41 to slide easily over the 
spindle. Each base portion 14, 16 also includes an annular ridge 28 
adjacent annular end sealing surface 20, 22 by which arrangement strength 
is maintained, while the amount of material used in the base portion is 
minimized. 
Spaced axially about 7/16" from each base portion 14, 16 is a 5/16" wide 
(in the axial direction) ring 50, 52 connecting each upright 18 to its 
adjacent uprights. A similar ring 54, axially centered on the tube, is cut 
away to provide gaps 56 between two pairs of uprights 180.degree. apart. 
Two further rings 60 and 62, 1/4" wide, respectively spaced 7/16" from 
rings 50 and 52, are also cut away to provide gaps 64 and 66 between two 
other pairs of uprights 180.degree. apart. Thus, the six gaps are in three 
different, axially spaced planes, and are circumferentially staggered with 
one between each pair of adjacent uprights. 
The ring edges are relieved by bevelling, e.g., at 80, between uprights to 
prevent yarn snagging. 
In use, yarn is wound on the tube at a 20.degree. slant, except at the ends 
of the tube where the winding is almost in a plane perpendicular to the 
tube axis. The winding tends to be tighter at the tube ends, and complete 
rings 50 and 52 prevent excessive deformation there. Protuberances 26 help 
to prevent yarn slippage. The spaces 19 between the uprights 18 allow for 
high dye saturation of the yarn. The outer surfaces of the uprights and 
rings comprise at least 50 percent of the cylindrical surface on which 
those surfaces lie, minimizing cross-overs and preventing the shrunken 
yarn from binding on the spindle. Advantageously, the inner surfaces of 
the uprights and rings also lie on a cylindrical surface. Dye can flow 
axially between spindle 12 and tube 10 between lugs 40. Surfaces 20, 22 
limit dye flow radially between adjacent stacked tubes. After dyeing, when 
the yarn dries and shrinks, the gaps in the rings allow pairs of adjacent 
uprights to approach each other (and the tube axis) locally at axially and 
circumferentially staggered positions over the major central portion of 
the tube, while the rings otherwise prevent excessive compression, 
twisting, or other deformation of the tubes. Since squeezing of the 
uprights will shorten the stack column, a spring loaded spindle nut 42 is 
attached to the top of the spindle to maintain a sealed column regardless 
of shrinkage or expansion of the column by applying a downward pressure on 
the stacked tubes. The tubes can be easily removed from the spindle, and, 
when the yarn is unwound, will spring back to their original position for 
reuse. 
Other embodiments are within the following claims.