US2091237A - Textile sheet and the manufacture thereof - Google Patents

Description

Aug. 24, 1937. H. D. EVANS 2,091,237

TEXTILE SHEET AND THE MANUFACTURE THEREOF Filed June 7, 1937 IN VE N TOR MAW! Eva. 5

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A 7 TORNEY Patented Aug. 24, 1937 UNITED STATES TEXTILE SHEET AND THE MANUFACTURE THEREOF Henry D. Evans, Saco, Maine, assignor to Pepperell Manufacturing Company, Boston, Mass., a corporation of Massachusetts Application June 7, 1937, Serial No. 146,924 3 Claims. (o1. 139-383) This invention relates to textile sheets and to methods of weaving the same, and particularly to novel sheets for beds wherein the threads of the sheet are of such character and are so distributed as to enhance the wearing qualities of the sheet without necessarily increasing the total weight or mature lengthwise tearing, the weight or strength of the filling should be increased, but I have found that merely such a change in the filling detracts from the flexibility and fillingwise elasticity of the sheet, rendering it less desirable as a commercialsheeting. Y

The object of the present invention is to provide a sheet which resists wear and tearing more than sheets of like grade with uniform weave now in use (that may be called a normal sheet) and which can be made without material, if any, increase in total weight over that of such normal sheets. According to my invention, the strength of the filling thread is increased, preferably by increasing its weight, and the filling crimp which would normally be lost by such a change in filling weight is restored, at least in the center of the sheet, by imparting to the filling in that portion, a crimp which is supernormal for such heavy filling yarns. I thereby am able to preserve the flexibility and fillingwise elasticity of the sheet which is characteristic of its grade, despite the use of such abnormally heavy filling yarns.

For imparting such crimp, I preferably increase the sley of the lighter warp threads in the center of the sheet and also, if necessary, either lighten the filling tension in the loom or reed the goods wider than usual. The distribution of the warp threads involves a minimum sley (warp threads per inch) in an area near each selvage, a maximum sley ina comparatively broad central area and, between each selvage area and the center area, a number of warp areas in which the sleys increase gradually, or step by step, from the selvage areas to the center area. In this manner, any increased warp breakage in the loom'which might occur from such increased sley in the center is averaged out by materially facilitating the weaving in the selvage areas. In my sheet there is no marked difference in sley on the lines between adjacent areas and therefore no tendency of the sheet to fold along such lines and to become weakened by repeated foldings along them. The changes in texture in my sheet are so gradual that there is no sensible diflerence in feel between adjacent areas of diiferent sleys.

These and further objects and advantages of my invention will appear from a more detailed description thereof in connection with the ac-- companying drawing, in which:

Fig. 1 is a diagrammatic plan view showing a preferred example of a double-bed sheet in the gray embodying my invention; and a Fig. 2 shows the filling crimp as hereinafter referred to.

To illustrate my invention there is shown in Fig. 1 a portion of a sheet, that may be 90 inches wide in the gray, embodying my invention, which is adapted for use on double beds. The sheet is of the grade in which in-the gray there would he usually in a normal sheet about 68 warp threads per inch of No. 22 yarn or thereabouts and 76 filling threads per inch also of No. 22' yarn or slightly lighter. The sheet, illustrated as an example of my invention, has in the gray a stronger and heavier filling, for example No. 18 yarn 72 threads to the inch, and warp threads of the usual No. 22 yarn. the size of the filling yarns, without other change, would objectionably decrease the filling crimp as hereinbefore setforth. I now compact the warp sley as indicated at 6 in Fig. 2, wherein the filling is indicated as having imparted to it the desired curvature in a sinuous path about the warp threads and to accentuate that crimp efiect I may also, if necessary, either lighten the tension on the filling in the loom or, preferably, reed the goods wider than usual, while maintaining proper warp tension. I

The sley is distributed in the following manner. The sheet is divided widthwise into a plurality of warp zones orareas a to it. Each of the sel- .vage areas 'a and k, for example about 8 to 12 inches wide, has a minimum density of warp threads, for example about 54 to 60 per inch, which is materiallyless than the number of warp threads per inch in a sheet of this grade of uniform weave. The area f in the middle of the sheet, where maximum crimp is desired, preferably about 48 to 58 inches wide in a double-bed sheet, has the maximum number of warp threads per inch, for example '70 to 76, which is materially greater than in a sheet of the same grade of uniform weave. The intermediate areas I) to e and 7' to g are each from about 1.5 to 3lnches wide. Each of such areas has a sley that is greater than that of the next outside adjacent area by from 2 to 8 warp threads, there being a gradual increase in the sley of successive areas from the selvage area to'the central area. At the immediate selvage there may be the usual few additional warp threads.

By so providing substantially sub-normal sleys adjacent the selvage I correspondingly increase Such an increase in warp areas and the widths of those areas may the ease of weaving and decrease the seconds to an unobjectionable number. Any decrease in the filling crimp in the selvage areas is of no moment as those areas are exposed comparatively little wear. Although the sleys of the areas near the selvage are below the sley in a sheet of the same grade and uniform weave, those areas are sufficiently sturdy warpwise to withstand the lesser degrees of wear to which they are subjected. My invention thus provides a sheet which wears more nearly uniformly from selvage to selvage than prior commercial sheets. Although warp threads in addition to the total number customarily used in a sheet of the same grade of uniform weave may be incorporated in a sheet embodying my invention, yet in the preferred embodiment of my invention there need be no such additional threads.

The strength and weight of the fillingshould, as stated, be materially increased as compared with a normal sheet of the same grade of uniform weave. This filling of increased strength, especially when combined with the increased sley of the central area, materially increases the re- T- sistance to longitudinal tearing, which tearing is the greatest factor in reducing the life of a sheet.

Obviously, the width of the sheet, the grades of the yarns, the specific sleys in the different be varied somewhat without departing from the principle of my invention. Thus a single-bed sheet, for example approximately 81 inches in width in the gray, would have a substantially narrower central area of maximum sley than that shown in the drawing, and it might well have a greater number of areas of graded sley between the central and selvage areas. Furthermore, if desired, the stepped arrangement of the areas of decreasing warp densities between the central area and the selvage areas may be replaced by a broad area in which the sley gradually tapers off from a maximum adjacent the central area to a minimum adjacent the selvage areas. The strength of the yarns used may be varied by varying their weight or by varying their quality or by both.

In modifications of my invention, the desirable characteristics, which are inherent in the sheet which I have specifically illustrated and described, are to be preserved. Thus. there should be no such abrupt difference in sley, either between the central and selvage areas or between any two contiguous areas, that a noticeable difference in texture feel results. The apparently even texture of the sheet embodying my invention, despite the non-uniform distribution of the warp threads, is an important commercial quality. Furthermore, my sheet, because it has no lines of abrupt difference in sley between adjacent areas, readily folds on any line, at random, parallel to the warp without tendency of the sheet to fold along predetermined lines at the edges of such areas. This is a material advantage because, if a sheet is repeatedly folded on such a line, the fabric is weakened at that line and will tend to break there sooner than elsewhere. My sheet may be easily calendered because it is freefrom abrupt changes in sley in adjacent areas.

To preserve these desirable characteristics in modifications of the specific embodiment of my invention, herein described. the strength or weight of the filling should be increased over normal, the crimp which is essential for fillingwise elasticity of the sheet, should be forced into the heavy filling, the difference between sleys in adjacent areas should be no greater than 8 warp threads per inch and the difference between the sley of the central area, which is the maximum, and that of the selvage areas, which is a minimum, should not exceed 30 warp threads per inch. I have found that a mere change in the sley of the sort suggested in the prior art is not effective for my purposes unless a change in the filling, as above described, is also made because such a more change in sley does not materially retard the premature failure of the filling threads.

My invention is not, of course, to be limited to any of the specific details, which have been set forth above, except as indicated in the appended claims, and in those claims the word crimp is used to designate approximately the difference in distance between adjacent warp threads as measured along the undulating filling threads and as measured in a straight line parallel to the plane of the cloth.

This application is a continuation in part of my prior application, Ser. N0. 54,926, filed December 17, 1935.

I claim:

1. The method of redesigning the construction of a sheet for beds, cribs and the like, having a desired filling-wise elasticity and having a uniform slcy, a uniform pick, and a given number of warp ends, each of which is at least as heavy as the filling, to increase the wear resistance of the sheet without substantially increasing its weight, which consists in substituting, for the filling, yarns of substantially increased weight and of uniform pick, providing, as warp, yarns that are lighter than the filling yarns and with substantially said given number of total warp ends to minimize any increase in weight of the sheet with the heavier filling yarns, redistributing the said warp ends by substantially increasing the sley in the central zone of the sheet and substantially reducing the sley in the selvage to minimize warp breakage during weaving, and providing, in the filling of said central zone, a crimp which is supernormal for that Weight of filling, whereby to impart to the sheet substantially said desired filling-wise elasticity.

2. As an article of manufacture, a sheet for beds, cribs and the like, consisting of heavy filling threads of uniform weight and pick, and warp threads that are lighter than the filling threads, the warp sley being graduated from a heavy sley in the central zone of the sheet to a comparatively light sley adjacent the selvage and the heavy filling having imparted to it, in said cen-' tral zone, a supernormal crimp and a sinuous curvature about the warp threads in said central zone, thereby imparting to the sheet the desired flexibility and elasticity.

3. As an article of manufacture a sheet for beds, cribs and the like, of a given predetermined grade consisting of filling threads of uniform pick and of a uniform weight which is excessive for that grade of sheet as normally detracting from the flexibility and filling-wise elasticity of the sheet characteristic of the said grade, and warp threads distributed with an excessively heavy sley in the central zone of the sheet, said filling threads having, in the central zone of the sheet, a supernormal crimp and a sinuous curvature about the warps, thereby imparting to the sheet said elasticity characteristic of the said grade.

HENRY D. EVANS.

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