Patent Description:
Although three-dimensional fabrics have been invented for a long time, even though techniques of making three-dimensional fabrics with varying thickness have been developed, such as disclosed in <CIT>, three-dimensional fabrics are always knitted independently. If the clothing design has a thick pad part formed by a three-dimensional fabric and a cloth surface part formed by a general knitted fabric, it is necessary to knit the three-dimensional fabric and the general knitted fabric separately, and then combine the two by sewing and splicing or using chemical adhesives. However, combining the three-dimensional fabric and the general knitted fabric by sewing and splicing will form spliced edges, which will greatly reduce the comfort of clothes. In addition, clothing with thick pads is generally used as a close-fitting clothing, and the stuffiness caused by long-term wearing may produce qualitative changes in chemical adhesives, which may affect the wearer's skin. Furthermore, chemical adhesives are not natural products, using excessively will also affect the environment.

<CIT> discloses a method for knitting and forming a weft-knitted fabric with varying thickness according to the preamble of claim <NUM>, comprising a first region and a second region having a double jersey knit structure. In the second region, during the formation of each course, including the interlocking process using spacer strand, the distance between a first needle bed and a second needle bed is gradually increased at a constant rate, or linearly, as the course is formed, thereby forming a slope, and a spacer knit fabric of variable thickness. In a third region in-between, the distance d remains constant during the formation of each course, thereby forming a plateau, and a spacer knit fabric of greater thickness than the other thickness regions. In the method a plurality of courses of a spacer knit construction are formed, the spacer knit construction comprising a first surface having a first set of loops formed on the first needle bed and a second surface having a second set of loops formed on the second needle bed, wherein the first surface is separate from the second surface. The method further includes interlocking at least one spacer strand with each of the first surface and the second surface, and adjusting the spacing between the first needle bed and the second needle bed while forming the plurality of courses of the spacer knit construction. However, when the first needle bed and the second needle bed are spaced relative to one another in distances, a spacer strand is provided for connecting the first surface to the second surface. At least two spacer strands are provided for providing a support capability.

<CIT> discloses a circular knitted textile fabric with at least one double-layered spacer structure 'and a method for its production, wherein a structural change from the double-layered spacer structure to a single-layered structure is completed, so that the circular-knit textile fabric has at least one structural change between the double-layered spacer structure and the single-layered structure. Although the knitted textile fabric is provided with a single-layered structure for connecting the double-layered spacer structures at both sides, the structure is not integrally formed.

<CIT> discloses a bras, comprising a first region having a three-dimensional structure and a first structural property, and a second region having a second structural property, the first and second regions being joined by a seamless transition, and wherein the three-dimensional structure is formed via a dual bed, V-bed knitting machine such that both front and back beds of the machine are used to knit the three-dimensional structure. The bras is provided with different numbers of yarns to form various thicknesses, but a supporting portion connected with the two surface layer portions and located between the two surface layer portions is not disclosed.

It is an object of the present invention to provide a method for knitting and forming a weft-knitted fabric enabling a better formation of the three-dimensional form of a weft-knitted fabric with varying thickness. According to a further related aspect there is to be provided a corresponding weft-knitted fabric.

These problems are solved by a method for knitting and forming a weft-knitted fabric as claimed by claim <NUM> and by a weft-knitted fabric as claimed by claim <NUM>. Further advantageous embodiments are the subject-matter of the dependent claims.

Accordingly, compared with the conventional techniques, the invention has the following features: the weft-knitted fabric of the invention has the basic structure and the three-dimensional structure during knitting, through the three-dimensional structure generating varying thickness, conventional processing procedure of pasting three-dimensional objects afterwards is eliminated; furthermore, a position where the weft-knitted fabric of the invention forms the three-dimensional structure is not limited, and can be adjusted according to design.

The detailed description and technical contents of the invention are described below with reference to the drawings.

Please refer to <FIG>. The invention provides a weft-knitted fabric <NUM> with varying thickness. The weft-knitted fabric <NUM> is knitted by a flat knitting machine <NUM> (as shown in <FIG>). The weft-knitted fabric <NUM> comprises at least one basic structure <NUM> and at least one three-dimensional structure <NUM>. The basic structure <NUM> is a general fabric structure without support function. Specifically, the basic structure <NUM> can be a single-layer fabric or a double-layer fabric. Structures of the single-layer fabric and the double-layer fabric are known to those having ordinary skill in the art, and thus will not be described here. On the other hand, the three-dimensional structure <NUM> and the basic structure <NUM> are integrally knitted, that is, the three-dimensional structure <NUM> is not connected by splicing or other methods after the basic structure <NUM> is knitted. A thickness of the three-dimensional structure <NUM> is greater than a thickness of the basic structure <NUM>, so when observing the weft-knitted fabric <NUM> laterally (as viewed from a visual angle in <FIG>), changes in thickness can be found. It should be understood that varying thickness or changes in thickness referred to in this specification is not thickness formed by stacking yarn layers, but changes produced when being observed laterally. In addition, the three-dimensional structure <NUM> comprises two surface layer portions <NUM>, <NUM> and a supporting portion <NUM> connected with the two surface layer portions <NUM>, <NUM> and located between the two surface layer portions <NUM>, <NUM>, and a junction between the three-dimensional structure <NUM> and the basic structure <NUM> is without the supporting portion <NUM>. Furthermore, in order to form a thickness of the three-dimensional structure <NUM>, the three-dimensional structure <NUM> is formed by at least one supporting yarn <NUM>, wherein the supporting yarn <NUM> deforms when at least one of the two surface layer portions <NUM>, <NUM> is pressed by force. The three-dimensional structure <NUM> can be regarded as a thick pad directly formed on the weft-knitted fabric <NUM>. Therefore, the weft-knitted fabric <NUM> of the invention can be used as a breast pad in women's clothing or a cushion pad in sportswear.

Please also refer to <FIG>, <FIG> and <FIG>. In addition to the foregoing, the invention also provides a method <NUM>. In the method <NUM>, the flat knitting machine <NUM> knits the weft-knitted fabric <NUM>. The method <NUM> comprises steps of.

Hereinafter, the basic structure <NUM> is used as the single-layer fabric to explain the method <NUM>, and it is assumed that the flat knitting machine <NUM> is ready to knit the basic structure <NUM> (the step <NUM>). A machine head <NUM> on the flat knitting machine <NUM> drives one of the two needle beds <NUM>, <NUM> to knit the basic structure <NUM> based on setting of a knitting process. When entering a process for knitting the three-dimensional structure <NUM> of the knitting process, the machine head <NUM> drives the two needle beds <NUM>, <NUM> to knit the two surface layer portions <NUM>, <NUM>. At this time, one of the two surface layer portions <NUM> (or <NUM>) is continuously knitted and formed from the basic structure <NUM>, the other of the two surface layer portions <NUM> (or <NUM>) is knitted and formed at this point of time. When the surface layer portion <NUM> is formed initially, the flat knitting machine <NUM> is set to use transfer knitting technique or tuck knitting technique to connect the surface layer portion <NUM> with the basic structure <NUM>. Further, the flat knitting machine <NUM> is controlled to be temporarily suspended from feeding the supporting yarn <NUM> at a junction <NUM> between the three-dimensional structure <NUM> and the basic structure <NUM>, and the supporting yarn <NUM> is fed to form the supporting portion <NUM> after the two surface layer portions <NUM>, <NUM> are knitted with a plurality of stitches. Therefore, the weft-knitted fabric <NUM> of the invention is a bag-like structure at the junction <NUM> between the three-dimensional structure <NUM> and the basic structure <NUM>. A point of time of feeding the supporting yarn <NUM> is after several stitches of the two surface layer portions <NUM>, <NUM> are knitted. A number of stitches temporarily suspended to be knitted can be adjusted based on characteristics of the weft-knitted fabric <NUM>. After the supporting yarn <NUM> participates in the knitting process, the supporting portion <NUM> is formed between the two surface layer portions <NUM>, <NUM>. The supporting portion <NUM> prevents the two surface layer portions <NUM>, <NUM> from being closely attached to each other, so that the three-dimensional structure <NUM> is visually thicker than the basic structure <NUM>. It should be understood that the method <NUM> of the invention is not limited to be ended immediately after completion of knitting of the three-dimensional structure <NUM>. According to fabric pattern design of the weft-knitted fabric <NUM>, the basic structure <NUM> is knitted again after the three-dimensional structure <NUM> is completed with knitting, as shown in <FIG>.

Please refer to <FIG>, <FIG>, <FIG> and <FIG>. Hereinafter, the basic structure <NUM> is used as the double-layer fabric to explain the method <NUM>, and it is assumed that the flat knitting machine <NUM> is ready to knit the basic structure <NUM> (the step <NUM>). The machine head <NUM> simultaneously drives the two needle beds <NUM>, <NUM> to knit the basic structure <NUM> based on setting of a knitting process and to produce two fabric surfaces <NUM>, <NUM> that constitute the double-layer fabric. In the process of knitting the two fabric surfaces <NUM>, <NUM>, the flat knitting machine <NUM> is set to use transfer knitting technique, tuck knitting technique, or a method of additionally feeding a cross-linking yarn <NUM>, so that the two fabric surfaces <NUM>, <NUM> are cross-linked and closely attached to each other. When entering a process for knitting the three-dimensional structure <NUM> of the knitting process, the two surface layer portions <NUM>, <NUM> are continuously knitted from the two fabric surfaces <NUM>, <NUM>. It should be noted that at a junction <NUM> of converting from the basic structure <NUM> to the three-dimensional structure <NUM> does not comprises any structure to connect the two surface layer portions <NUM>, <NUM>. In technical terms of the industry, the supporting portion <NUM> is implemented with drop stitches at a junction between the basic structure <NUM> and the three-dimensional structure <NUM>. Afterwards, the supporting yarn <NUM> is fed to knit the three-dimensional structure <NUM>, knitting of the three-dimensional structure <NUM> is the same as described above and thus will not be repeated.

A thickness of the three-dimensional structure <NUM> is determined by a length of the supporting yarn <NUM>, and a length of the supporting yarn <NUM> during knitting process depends on a width of a mouth <NUM> (shown in <FIG> and <FIG>) of the flat knitting machine <NUM>. It should be understood that changes in a width of the mouth <NUM> also affect a forming size of yarn loops. When a width of the mouth <NUM> is larger, knitted yarn loops will become larger, and it will be difficult for excessively large sized yarn loops to form fabric surface structure. Therefore, if a size of the mouth <NUM> cannot be changed during knitting process, in designing a thickness of the three-dimensional structure <NUM>, a size of yarn loops of the basic structure <NUM> and the two surface layer portions <NUM>, <NUM> must be considered. Furthermore, if the flat knitting machine <NUM> is capable of changing a width of the mouth <NUM> without stopping knitting during knitting process, the problem that a thickness of the three-dimensional structure <NUM> being limited by a single width of the mouth <NUM> can be tackled. The applicant of the invention has provided flat knitting machine structures with variable mouth width during knitting process as disclosed in Taiwan Patent No. <CIT>, <CIT>, <CIT>, and <CIT>. Please refer to <FIG>. When the flat knitting machine <NUM> is controlled to knit the supporting portion <NUM> of the three-dimensional structure <NUM>, the flat knitting machine <NUM> drives two knock-over bits <NUM>, <NUM> of the two needle beds <NUM>, <NUM> to displace to change a size of the mouth <NUM> of the flat knitting machine <NUM>, until a size of the mouth <NUM> is adjusted to meet the knitting requirements, the flat knitting machine <NUM> performs knitting of the supporting portion <NUM>. In this way, a height of the supporting portion <NUM> will no longer be a fixed value, and the three-dimensional structure <NUM> will no longer have a single thickness but is capable of varying in thickness, as shown in <FIG>.

Claim 1:
A method (<NUM>) for knitting and forming a weft-knitted fabric (<NUM>) with varying thickness by a flat knitting machine (<NUM>), the method (<NUM>) comprising steps of:
driving the flat knitting machine (<NUM>) to knit a basic structure (<NUM>) by at least one of two needle beds (<NUM>, <NUM>) of the flat knitting machine (<NUM>), wherein the basic structure (<NUM>) is selected from a single-layer fabric or a double-layer fabric; and
controlling the two needle beds (<NUM>, <NUM>) on the flat knitting machine (<NUM>) to knit a three-dimensional structure (<NUM>) connected with the basic structure (<NUM>), wherein a thickness of the three-dimensional structure (<NUM>) is greater than a thickness of the basic structure (<NUM>), the three-dimensional structure (<NUM>) comprises two surface layer portions (<NUM>, <NUM>) and a supporting portion (<NUM>) connected with the two surface layer portions (<NUM>, <NUM>) and located between the two surface layer portions (<NUM>, <NUM>);
characterized in that
the flat knitting machine (<NUM>) is controlled to be temporarily suspended from feeding a supporting yarn (<NUM>) at a junction (<NUM>) between the three-dimensional structure (<NUM>) and the basic structure (<NUM>) so that the junction (<NUM>) is without the supporting portion (<NUM>), and the supporting yarn (<NUM>) is fed to form the supporting portion (<NUM>) after the two surface layer portions (<NUM>, <NUM>) are knitted with a plurality of stitches.