Method and device for the manufacturing of fabrics with at least two different pile heights in a same pile row

#This application claims the benefit of Belgian Application No. BE-2010/0023 filed Jan. 15, 2010 and PCT/IB2011/000029 filed Jan. 11, 2011, International Publication Number WO 2011/086449, which are hereby incorporated by reference in their entirety as if fully set forth herein.

#The present invention relates, on the one hand, to a method for weaving pile fabrics with at least two different pile heights in the same pile row, wherein the fabrics comprise weft threads, ground warp threads and pile-warp threads, wherein these pile-warp threads are interlaced in the fabric, according to a pattern, in a figure-forming manner or are inwoven in a non-figure-forming manner, and which, when they are figure-forming, form pile with a well-defined pile height. On the other hand, the present invention relates to a device for manufacturing such fabrics.

#There is clear evidence of a strong trend to realize pile fabrics with different structures within the same fabric. For instance, EP 1 347 087 describes a method and a device for manufacturing, in a double-face weaving technique, fabrics containing a large variety in structure. It is thus possible to make virtually unlimited combinations of cut pile with loops and with figure-forming warp threads (yarns) which on the pile side float over one or more wefts prior to being interlaced (so-called ‘flat weave’).

#In the following description, reference is made by way of reference numerals to the hereto appended drawings, in which:

#FIG. 1: is a schematic representation of a double-face weaving device according to the present invention and designed for the application of the method in accordance with this invention.

#FIG. 2: is a side view of the double-face weaving device represented in FIG. 1.

#In order to manufacture fabrics with at least two pile heights (a, b) in the same pile row, this invention provides, inter alia, a method which allows fabrics to be realized on single and double-face weaving devices with cut pile and/or loop pile in different pile height, with a free choice in terms of position and pile height of the zones with varying pile height. The method in accordance with the present invention relates, in particular, to a method for weaving pile fabrics with at least two different pile heights (a. b) in the same pile row, wherein the fabrics comprise weft threads, ground warp threads and pile-warp threads (1, 2), wherein these pile-warp threads (1, 2) are interlaced in the fabric, according to a pattern, in a figure-forming manner or are inwoven in a non-figure-forming manner, and which, when they are figure-forming, form pile with a well-defined pile height, wherein a first set of pile-warp threads (1) is inserted in such a way that these move virtually without strain or under light strain onward into the just formed fabric (3) and wherein at least a second set of pile-warp threads (2) is inserted in such a way that, in relation to the first set of pile-warp threads (1), they move with a higher strain onward into the just formed fabric (3).

#The method in accordance with the invention can be used both in single-face and double-face weaving.

#In double-face weaving, two pile fabrics are manufactured at the same time. A topmost and a bottommost ground fabric of warp threads (yarns) and weft threads (yarns) are formed, whilst pile-warp threads (1, 2) (yarns) are interlaced alternately in one and the other ground fabric. After this, the pile-warp threads (1, 2) are cut through between the two ground fabrics by means of a known cutting device, so that two ground fabrics are obtained, which each have a series of upright lengths of pile thread, also referred to as the pile. In the embodiments according to the prior art, the interspace between the topmost and bottommost ground fabric is determinant for the length of those parts of the pile-warp threads which run between the two ground fabrics, and thus also for the pile height thereof. During the double-face weaving, this interspace must be kept as constant as possible. In order to achieve this, on double-face weaving machines having two weft insertion levels, lancet devices are utilized. Here, in a lancet holder, a series of lancets are used, which lancets are distributed over the weaving width and extend in the warp direction between the warp systems and between the blades of the reed. These lancets then serve as spacers for keeping the two ground fabrics at a distance apart. The known lancets consist of an elongate metal strip with a small thickness (for example 0.1, 0.2, 0.3 or 0.4 mm) and with a height which is equal to the desired interspace between the two ground fabrics in double-face weaving, for example 3, 5, 8, 10, 15, 18, 20, 22, 24, 30 mm. For specific use with long-haired carpets, referred to as shaggy, and also in the weaving of artificial turf, even lancets of 50, 70, 100 to 140 mm height are known. One end is designed for reception in the lancet holder, whilst the other end ends in a point, with the point ending up above the bottommost cutting table of the weaving machine.