US3331402A - Looms with means for correcting weft thread distortion - Google Patents

Description

y 1967 J. KATHRINER' ETAL 3,331,402

LOOMS WITH MEANS FOR CORRECTING WEFT THREAD DISTORTION Filed June 22, 1965 4 Sheets-Sheet 1 Pi. f

Inventors y 1957 J. KATHRINER ETAL 3,331,402

LOOMS WITH MEANS FOR CORRECTING WEjFT THREAD DISTORTION Filed June 22, 1965 4 Sheets-Sheet 2 Fllg. 6

lnvenzom y 1967 J. KATHRINER ETAL 3,331,402

LOOMS WITH MEANS FOR CORRECTING WEF'T THREAD DISTORTION I Filed June 22, 1965 4 Sheets-Sheet F lnvenzors [Willa y 3957 J. KATHRINER ETAL 3,331,402

LOOMS WITH MEANS FOR CORRECTING WEFT THREAD DISTOHTION 4 Sheets-Sheet 4 Filed June 22, 1965 Inventors fi M hh v M I W A14%% 74 14 United States Patent 3,331,402 LOOMS WITH MEANS FOR CORRECTING WEFI THREAD DISTORTIGN Josef Kathriner, Winterthur, Switzerland, and Johann Haberkern, Eilend'orf, Germany, assignors to Sulzer Brothers Limited, Winterthur, Switzerland, a Swiss company Filed June 22, 1965, Ser. No. 465,932 Claims priority, application Germany, July 4, 1964, F 43,348; Switzerland, Nov. 27, 1964, 15,311/64 2 Claims. (Cl. 139291) This invention relates to looms provided with temples tending to hold the woven fabric to full width. More particularly, the invention is concerned with a loom with temples, which is provided with novel means for correcting the distortion of the weft threads resulting from the action of the temples.

In the weaving of fabrics on looms equipped with temples and with positively acting fabric take-up means elfecting a constant advance of the fabric, lengths of the weft threads near the side edges of the goods tend to be displaced to the rear along curved lines. Such displacement of the weft threads is particularly troublesome in fabrics with transverse stripes or checked patterns, such as glen checks, since, in such fabrics, the distortion is clearly apparent. Weft thread distortion results from the application to the fabric by the temples of aforce opposing the tension advancing the fabric, so that the fabric undergoes a backward pull on marginal zones of a width about equal to the length of the temples and the pull increases toward the edges. The tendency of this backward pull to hold back the weft threads in the portions of the fabric to which it is applied, produces displacement of end portions of the weft threads toward the rear, that is, in the direction opposite to the direction of fabric advance.

Efforts to place fabrics with weft thread distortion in salable condition have heretofore been directed mainly to reducing the distortion in the pressing and decating equipment used in finishing operations. The results obtained, however, have not been wholly satisfactory since the distortion is likely to reappear in the finished article when the latter is ironed. Efforts have also been made to prevent weft thread distortion by employing temples which extend over the entire width of the fabric but these efforts have not been successful because the pressure of the temples decreases toward the middle of the cloth and weft thread distortion still occurs.

The present invention is, accordingly, directed to the provision of a loom with temples, which is equipped with novel means for correcting distortion of the weft threads resulting from the action of the temples. In a loom constructed in accordance with the invention, a member having a guide surface, over which the fabric travels with a change of direction, is disposed between the temples and the takeup means and the guide surface is shaped to distort the central portion of the fabric in relation to the margins to compensate at least partially for the displacement of the weft threads produced by the temples. As weft thread distortion occurs because the marginal zones of the fabric are retarded by temple action in relation to the central zone, the guide surface is formed to cause the central zone of the fabric to travel a longer distance than the marginal zones between the temples and the take-up means. As a result, the weft threads are straightened and the distortion eliminated.

In the preferred form of the invention, the guide surface is provided in the form of a member mounted on the loom transversely of the direction of cloth travel and relieved over end portions corresponding in position to the temples. The member is preferably made of a number of separate pieces each carrying a part of the guide ice surface and the pieces are interengageable and may conveniently comprise a tubular central piece and end pieces releasably secured to the loom and provided with axial pins extending into the tubular piece. The length of the member may then be varied by the use of one or more spacer rings placed on the axial pins between the central piece and the end pieces.

Since the cloth selvages undergo considerable distortion before reaching the guide surface, the outermost portions of the guide surface engaging the selvages may advantageously be formed with extra relief. This insures that the selvages will be deflected by the surface without tension and distortion.

For a better understanding of the invention, reference may be made to the accompanying drawings, in which FIG. 1 is a diagrammatic side elevational view showing the path of travel of the cloth in a loom constructed in accordance with the invention;

FIG. 2 is a diagrammatic plan view of the parts shown in FIG. 1;

FIG. 3 is a view partly in elevation and partly in crosssection of a part of the distortion-correcting member of the invention; v

FIG. 4 is a plan view of a modified form of member;

FIGS. 5 and 6 are diagrammatic plan views showing, respectively, a fabric with weft thread distortion and a fabric in which such distortion has been corrected;

FIG. 7 is a diagrammatic side elevational view illustrating the use of a member of the invention in a loom having a single temple at each side;

FIG. 8 is a developed plan view of the parts shown in FIG. 7;

FIG. 9 is a view similar to FIG. 7 of a loom equipped with a pair of temples at each side;

FIG. 10 is a view similar to FIG. 8 of the loom shown in FIG. 9;

FIG. 11 is a diagrammatic side elevational view of a loom provided with a modified distortion-correcting member;

FIG. 12 is a developed plan view of the parts shown in FIG. 11; and

FIG. 13 is a view similar to FIG. 11 but showing a modified construction.

In the loom diagrammatically illustrated in FIGS. 1 and 2, the fabric 2 leaving the shed 1 travels over a table 3 and turns downward at the end of the table. The fabric then passes through a two-roll stand 4 applying tension to the fabric and over a deflecting roller 5 to a cloth or take-up beam 6. A short distance beyond the shed 1, the edge zones 7 of the fabric pass through temples 8 at the sides of the table 3.

The temples are of conventional construction and each includes a roller 9 with its aXis in the plane of the table top and the fabric is guided over the rollers beneath the temple caps 16. The resistance applied by the temples to the sides of the fabric causes the side margins of the fabric to lag with the lag increasing toward the edges. As a result, the weft yarns become distorted as indicated diagrammatically by the curved lines 11 in FIG. 2. To correct this distortion, the front end of the table 3 is provided with a member 13 having a guide surface, over which the fabric travels with a change of direction, and this surface acts on the central zone 12 of the fabric to increase the length of its travel between the temples and the take-up means.

The member 13 in the form shown in FIG. 3 is a bar of substantially circular cross-section except that, near its ends, the front surface 14 of the bar is cut back or relieved with the amount of relief corresponding roughly to the magnitude of distortion of the Weft yarn. The fabric traveling over the bar is thus subjected to an adjustment of the weft threads which is greatest over the central zone of the fabric and decreases to zero at the outer edges of the fabric.

Referring to FIG. 3 the member 13 includes end pieces 15, each provided at its outer end with a bracket 16 adapted to be attached to the table. At its inner end, each piece has an axial pin 17 receivable into a tubular central piece 18 rigidly connected to the loom and serving as a guide for the central zone of the fabric. As variations in fabric width occur, the pins 17 on the end pieces can be inserted varying distances into the tubular piece 18 with any spaces between the end pieces and the central pieces filled by spacer rings 19.

The transition between the largest cross-section of the bar 13 and its smallest cross-section in a relieved portion 14 corresponds in length substantially to the length of the associated temple. In shape, the relieved portions 14 correspond substantially to the weft yarn distortion represented by the curved lines 11 and must be adapted to the particular fabric being woven by a small amount of shaping, which can be readily done. To prevent the cloth selvages from being further stretched, the guide bar may be additionally relieved near its ends which engage the selvages, as indicated at 20 in FIG. 4.

By way 'of illustration, a length of fabric 2 with typical weft yarn distortion indicated by the curved lines 11 is shown in FIG. 5, while FIG. 6 shows a length of similar goods, from which weft yarn distortion is absent. A fabric having the appearance of that shown in FIG. 6 can be readily produced by the use of the invention.

The loom diagrammatically illustrated in FIGS. 7 and 8 is provided with a temple 8 at each side and, during the take-up, the temples cause the margin-a1 zones 7 of the fabric 2 to lag in relation to the central zone 12, so that a distortion of the weft threads by a maximum amount a takes place. In order to correct such distortion, the breast beam 21 of the loom carries a member 22 made up of end pieces 15 and a central piece 26, the length of which can be varied by the use of spacer rings to adapt the member to the fabric width. The end pieces 15 are secured to the central piece 26 at points 27. The curvature 23 of each piece 15 corresponds to the curvature of the weft yarns represented by the lines 11, so that the outer end of each piece 15 is relieved or cut back by the same distance a as the weft threads are distorted. As a result of traveling over the guide surface of the member 22, the weft threads assume the position indicated by the lines 1121 and thus become straight and undistorted.

The loom shown in FIGS. 9 and 10 includes a pair of temples 8, 8:: on each side of the loom and the marginal zones of the fabric are caused by the temples to lag in relation to the central zone, so that the maximum weft yarn distortion is equal to the distance 2a and the curvature 24a of the distorted Weft yarns 11 is correspondingly greater than in the fabric shown in FIG. 8. Accordingly, the end pieces 15a of the member 22 are given increased relief, so that the guide surface near the outer end of each piece15 is set back by a distance 2a. In shape, the curvature 23a of the end pieces corresponds to the curvature 24a of the weft yarns.

In the loom shown in FIGS. 11 and 12, the guide surface, which causes the distortion of the weft yarns, is formed on roller 31 which has a shape similar to the shape of the bars 13 or 22. The roller 32 is of a shape to mate with the roller 31 and the fabric passes between the rollers. The rollers may be rotated by the passage of the fabric between them or may be driven, if desired.

In the loom shown in FIG. 13, the correction of weft thread distortion is effected by means of a single roller 31 and the mating roller 32 is not used. When the roller 31 is used alone, it may be so mounted as to perform the function of the deflecting roller 5 (FIG. 1).

We claim:

1. In a loom having fabric take-up means and temples having each a length extending from a selvage of the fabric part-way toward the other of said temples, the improvement which comprises a guide over which the fabric passes with a change of direction in its passage from the temples to the take-up means, said guide having a length greater than the separation of the adjacent ends of said temples and having a convex substantially cylindrical surface over a central portion of the guide of length substantially equal to the separation of said temples and having a surface relieved below said cylindrical surface over each of the two end portions of said guide, said relieved surfaces being convex in sections perpendicular to the elements of said cylindrical surface and being concave in sections parallel to said elements.

2. The improvement according to claim 1 wherein the surfaces of said end portions include each a supplementary relief at the outer ends thereof, the separation of the surfaces so supplementarily relieved being substantially equal to the separation of the outer ends of said temples.

References Cited UNITED STATES PATENTS 545,607 9/1895 Palmer l39305 587,324 8/1897 Palmer l39305 X 1,132,999 5/1916 Ayer 139-291 1,836,309 12/1931 Cartwright 139-291 2,884,015 4/1959 Bechter 139291 MERVIN STEIN, Primary Examiner. H. S, JAUDON, Assistant Examiner.

Claims (1)

1. IN A LOOM HAVING FABRIC TAKE-UP MEANS AND TEMPLES HAVING EACH A LENGTH EXTENDING FROM A SELVAGE OF THE FABRIC PART-WAY TOWARD THE OTHER OF SAID TEMPLES, THE IMPROVEMENT WHICH COMPRISES A GUIDE OVER WHICH THE FABRIC PASSES WITH A CHANGE OF DIRECTION IN ITS PASSAGE FROM THE TEMPLES TO THE TAKE-UP MEANS, SAID GUIDE HAVING A LENGTH GREATER THAN THE SEPARATION OF THE ADJACENT ENDS OF SAID TEMPLES AND HAVING A CONVEX SUBSTANTIALLY CYLINDRICAL SURFACE OVER A CENTRAL PORTION OF THE GUIDE OF LENGTH SUBSTANTIALLY EQUAL TO THE SEPARATION OF SAID TEMPLES AND HAVING A SURFACE RELIEVED BELOW SAID CYLINDRICAL SURFACE OVER EACH OF THE TWO END PORTIONS OF SAID GUIDE, SAID RELIEVED SURFACES BEING CONVEX IN SECTIONS PERPENDICULAR TO THE ELEMENTS OF SAID CYLINDRICAL SURFACE AND BEING CONCAVE IN SECTIONS PARALLEL TO SAID ELEMENTS.

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