The invention relates to the technical field of circular knitting, and more particularly, to the circular knitting of footwear.
Knits may be produced in a known manner by varying the selection of needles and yarns so as to obtain a knit with different mechanical or aesthetic characteristics depending on the zones of the knit considered.
For example, in a known manner, extra yarns may be added, known as reinforcement yarns, in certain zones of the knit, such that the knit contains more material in these zones. These are therefore dense zones.
It is possible to add a reinforcement yarn only every other row of stitches, within a dense zone. The density obtained is higher than that of the rest of the knit, but not sufficiently so. If used to increase the strength of the knit, it does not reinforce the knit sufficiently for it to have a decent level of wear resistance. If used to increase the opacity of the knit, the addition of the extra yarn results in an irregular appearance of the knit, in that it causes unsightly stripes to appear. This is due to the spacing between the rows of stitches containing the reinforcing yarn, visually creating a succession of fully and slightly opaque lines.
It is also possible to add a reinforcement yarn for each row of stitches, within the dense zone. The density obtained is satisfactory, because it is significantly higher than that of the rest of the knit. However, this solution leads to production difficulties and knitting defects.
Indeed, the reinforcement yarns are used only in dense zones of the knit. When they are not used, they must be held in a so-called idle position within the knitting machine. With reference to
However, if there is a need to obtain zones that are much denser than the rest of the knit, for example, by adding a reinforcement yarn for each row of stitches, the number of yarns in the knit becomes too high and the brake plate (4) can no longer play its role of retaining the yarns: in fact, adjusting the air-gap under the brake plate (4) requires either a huge or excessive amount of attention to detail and is very difficult to achieve due to the very design of the machine. The idle yarns are not properly positioned, such that they are not picked correctly by the needles. This results in machine stoppages, or knitting defects. In the latter case, the dense zone is not homogeneous and the knit is produced with a visual defect.
On the other hand, unused reinforcement yarns are cut off, and the off-cuts must be removed from the knitting machine. When too much reinforcement yarns are used, the machine is unable to remove all of the waste, such that it accumulates and creates a blockage at the removal point. Once again, the consequences may be a machine stoppage, or at the very least, a knitting defect.
One of the aims of the invention is to overcome the disadvantages of the prior art, by proposing an industrial and optimised knitting method enabling dense zones to be obtained on one knit. These dense zones can be used to increase the opaqueness of the knit at certain specific locations and thus create shapes for aesthetic purposes, or to reinforce the knit to make it more wear-resistant.
For this purpose, a method has been developed for circular knitting of a knit by using a knitting machine, wherein the circular knit is formed from a plurality of rows of stitches knitted with a stitch-forming yarn, and comprises at least one dense zone.
The notion of a “circular knit” is defined as a knit produced on a circular loom, as suggested by the standard ISO 8388. Because of the way it is manufactured, this circular knit has visible characteristics such that it may be differentiated from a tubular “straight knit” manufactured on a straight loom. In particular, a visible feature of the “circular knit” is the absence of an edge stitch binding zone. The edge stitch binding zone is located on a tubular “flat knit”, due to the need to form a tube, for connecting the adjacent edges of the flat knit produced. Thus, to create a “circular knit”, it is possible to produce a tubular knit with the same stitch structure around the entire circumference of the item. On the contrary, on a flat knit, a visible line will necessarily appear along the tubular item with a stitch structure different from the rest of the item. This line corresponds to this edge stitch binding zone of the edge stitches.
According to the invention, the dense zone or zones of the circular knit is or are achieved via knitting an alternation, in each row of stitches of a first and second row of jersey stitches, such as:
The combination of the two rows of stitches obtained by their specific needle selections densifies the knit, while avoiding the need to add a reinforcing yarn to each row of stitches, which is responsible for production losses due to blockages and non-quality. Secondly, the upper binding points between the rows of stitches enable these rows to be tightened. As a result, knit with sufficiently dense zones can be knitted efficiently, safely and repeatably.
To strengthen the binding between the two rows of stitches, for the first selection of needles, the knitting of a tuck stitch is preferably performed every other stitch, within the first row of stitches. This is of course in the dense zone. This preferred method enables the rows of stitches to be tightened to a satisfactory level of density.
Alternatively, for the first selection of needles, the knitting of a tuck stitch may be performed one stitch in three or one stitch in four or one stitch in five, within the first row of stitches.
The difference in density between dense and non-dense zones formed on a basic jersey knit is substantial. The ratio between the density of a dense zone formed on a wefted knit and that of a non-dense zone formed on a wefted knit is supposedly to be around 20%. Similarly, the ratio between the density of a dense zone formed on a non-wefted knit and that of a non-dense zone formed on a non-wefted knit is supposedly to be around 20%.
The size of the dense zone depends on the number of rows and columns knitted by using this method.
Advantageously, the method can also include knitting a weft yarn between each row of stitches. This appearance will be described in greater detail below.
Two different stitching layouts are proposed to meet the demands of the two possible uses of these dense zones. These two stitching layouts differ in the need for and placement of a weft yarn.
In the first of the two preferred uses, the dense zones are used to increase the opaqueness of the knit at specific points and thus create shapes for aesthetic purposes. The dense zones are produced in such a way that they create uniform geometric shapes (the geometric shapes are identical or similar) evenly dispersed over the surface of the knit, with the total surface area of the dense zones being less than 10% of the total surface area of the knit, and preferably less than or equal to 5% of the total surface area of the knit. It is possible, for example, to obtain a plumetis effect directly in knitting, without the need to embroider the geometric shapes on the knit.
In this first, aesthetic use, the method may also involve knitting a weft yarn between the rows of stitches. This weft yarn makes it possible to impart additional properties to the knit, such as improved stability, greater elastic strength, or a different feel or visual appearance. In particular, the addition of a weft yarn makes it possible to control the elasticity of a textile item, especially a compression and/or support item, by imparting greater elastic strength.
According to standard ISO 8388, basic knitting on a circular knitting machine is defined as knitting on all needles known as “plain jersey knitting” without weft. According to the same standard, point 3.1.30, in the case of a wefted jersey-based knit, one or more weft yarns are inserted into the knit, in rows known as “load-float”. The concept of a “weft yarn” and the way it is inserted into a knit are therefore per se known to those skilled in the art.
The space between the row of stitches where the weft yarn is inserted is called the “weft row”.
For this first use, in the case where the knit includes a weft yarn, the weft yarn is inserted between each row of stitches, by creating a float that corresponds to the needle that knitted a stitch on the first row of stitches. As a result, the weft yarn lies between the first row of stitches and the second row of stitches, and also between the second row of stitches and the first row of stitches. The weft yarn is picked only every other needle. This creates a columnar alignment between the stitch in the first row of stitches and the float in the weft row. The floats of the weft yarn are staggered (i.e., on opposite needles, or offset) in relation to the next weft row. In other words, the floats are offset relative to each other, from one row of weft to the next, such that at each row of weft, loads and floats alternated along the same column. The result is a uniform, smooth appearance, with no ribbing.
According to one embodiment of this first use, the weft yarn is inserted between each row of stitches, by creating two or three or four consecutive floats corresponding to the needles that have knitted a stitch on the first row of stitches. The weft yarn is picked only every third needle, every fourth needle or every fifth needle, respectively. The weft yarn floats are staggered in relation to the next weft row, such that the floats are offset from each other from one weft row to the next. This results in multi-column floats that are offset to each other from one weft row to the next, without overlapping.
The invention also relates to a knit provided with at least one dense zone according to the aforementioned technical characteristics.
The invention also relates to a textile item comprising at least one knit provided with at least one dense zone according to the aforementioned technical characteristics.
According to one embodiment, the article(s) produced may be either stockings, tights or socks.
Preferably, it is a compression and/or support article, in which case, it is intended for medical use.
In the second preferred use, the dense zones are used to reinforce the knit to make it more resistant to wear. To protect the textile item from wear and tear where it is most engaged, the dense zone(s) is preferably created on a surface of the item in contact with the heel and/or a surface of the item in contact with the toes and/or a lower surface of an individual's foot when the item is worn by an individual.
In this second intended use, the knit necessarily comprises a weft yarn.
The weft yarn is inserted between each row of stitches, by creating a float that corresponds to the needle that knitted a load on the first row of stitches. As a result, the weft yarn lies between the first row of stitches and the second row of stitches, and also between the second row of stitches and the first row of stitches. The weft yarn is picked only every other needle. This creates a columnar alignment between the load in the first row of stitches and the float in the weft row. The weft yarn floats are created in the same columns from one weft row to the next. In other words, the floats are created in the same columns, in each weft row, such that the floats are aligned. This alignment results in a ribbed appearance and a knit with improved strength.
According to one embodiment of this second use, the weft yarn is inserted between each row of stitches, by creating two or three or four consecutive floats corresponding to the needles that have knitted a load on the first row of stitches. The weft yarn is picked only every third needle, every fourth needle or every fifth needle, respectively. The weft yarn floats are created in the same columns from one weft row to the next, such that the floats are aligned with each other.
The invention also relates to a knit provided with at least one dense zone according to the aforementioned technical characteristics.
The invention also relates to a textile item comprising at least one knit provided with at least one dense zone according to the aforementioned technical characteristics.
According to one embodiment, the article(s) produced may be either stockings, tights or socks.
According to one embodiment, the textile item comprises at least one knit provided with at least one dense zone according to the second use described previously, wherein the weft yarn is inserted between each row of stitches. Said item is stockings, tights or socks, and the dense zone or zones are located on a surface of the item in contact with the heel and/or a surface of the item in contact with the toes and/or a surface in contact with the lower surface of the foot of an individual when the item is worn by an individual.
The textile item is necessarily a compression and/or support item, for example, for medical purposes, because the constituent knit of the item comprises a weft yarn.
The invention relates to a circular knitting method, a circular knit (1), and a textile item (3) incorporating such a circular knit (1). A combination of needle selections used is shown in
The rows of stitches (M1, M2) are knitted using any suitable yarn. In the case of footwear, the stitch-forming yarn (5) may particularly be a single-gimped or double-gimped yarn, for example, comprising an elastane core yarn and polyamide coating yarns.
In a preferred embodiment, the core yarn is a elastane yarn with a titre of 22 dtex, double-gimped polyamide coating yarns with a titre of 22 dtex comprising 20 filaments, and with false twist. I must be remembered that 1 dtex=10−7 kg/m. In this embodiment, the two coating yarns are preferably reversed in their false-twist directions.
The reinforcing yarn (6) may be of any suitable type. A preferred reinforcement yarn (6) is a 13-filament, false-twisted polyamide yarn with a titre of 44 dtex.
As can be seen from the diagrams in
In this way, the stitch-forming yarn (5) and the reinforcement yarn (6) inserted in the second row of stitches (M2) are knitted by the needles of the tuck stitches of the first row of stitches (M1). The rows (M1, M2) are thus brought closer together.
In the needle selection diagram in
In the first aesthetic use, the dense zones (2) obtained by the invention have a greater thickness than the rest of the knit (1). By judiciously choosing the dimensions and distribution of these dense zones (2) on the knit (1), it is possible to obtain textures or appearances that are usually obtained by additional manufacturing steps. For example, a plumetis is traditionally obtained by embroidering a yarn on a textile item, so as to obtain small dots in relief.
This first use is shown by the stitch diagram in
In terms of plumetis, the raised dots are small. Depending on the desired effect and to highlight the relief of the dense zones (2), the total surface area of the dense zones (2) is less than 20% of the total surface area of the knit (1), or even less than 10%, and preferably less than or equal to 5%.
It is specified that it is understood by those skilled in the art that the dense zones created by means of the needle selection shown in
With reference to the same
The geometric shape of the dense zone (2) to be repeated to obtain the plumetis effect may be adapted depending on aesthetic requirements. The dense zone may be circular, oval, rectangular or any other desired shape.
The even distribution of the dense zones (2) on the knit (1) may include, for example, symmetries or rotations.
As illustrated in
The weft yarn (7) is used to impart special properties to the knit (1), and may be of any type suitable for this purpose. In particular, the addition of a weft yarn makes it possible to control the elasticity of a textile item, especially a compression and/or support item, by imparting greater elastic strength. This may be a single-coated or double-coated yarn, for example, with an elastane core yarn and polyamide coating yarns.
In a preferred embodiment, the core yarn is an elastane yarn with a titre of 310 dtex, double-twisted with polyamide coating yarns with a titre of 22 dtex, comprising 20 filaments, and with false twist. In this embodiment, the two coating yarns are preferably reversed in their false-twist directions.
In the needle selection diagram shown in
By using this diagram, the reinforcement yarn (6) of the second row of stitches (M2) is picked at positions (c) with the stitch-forming yarn (5) of the next row of stitches (M1).
In this way, it is possible to obtain a functionalised knit (1), for example, in a compression and/or support item having superior elastic strength, further comprising dense zones (2) that are significantly denser than the rest of the knit (1) and which have a satisfactory aesthetic appearance when worn, i.e., there are no stripes or striations despite the fact that the reinforcing yarn (6) is inserted only every other row of stitches.
The space between the row of stitches (M1, M2) where the weft yarn is inserted is called the “weft row” (T).
For this first aesthetic use, in the case where the knit includes a weft yarn, the weft yarn (T) is inserted between each row of stitches, by creating a float (i) that corresponds to the needle that knitted a stitch (m) on the first row of stitches (M1). As a result, the weft yarn lies between the first row of stitches (M1) and the second row of stitches (M2), and also between the second row of stitches (M2) and the first row of stitches (M1). The weft yarn (7) is only picked every other needle. This creates a columnar alignment between the stitch (m) in the first row of stitches (M1) and the float (i) in the weft row (T). The floats of the weft yarn (i) are staggered (i.e., on opposite needles, or offset) in relation to the next weft row. In other words, the floats (i) are offset relative to each other, from one row of weft (T) to the next, such that at each row of weft (T) loads (c) alternate with floats (i) in the same column. The result is a uniform, smooth appearance, with no ribbing.
The textile item (3) may be a compression and/or support article, for example for medical purposes. In this case, the knit of item (1) preferably comprises a weft yarn (7).
The textile item (3) may also be stockings, socks or tights, i.e., for non-medical use. In this case, the knit generally comprises no weft yarn (7). In the second preferred use, dense zones are used to reinforce the knit. Improved strength is particularly advantageous in regions of the knit subjected to high mechanical stress when the item is worn, such as the sole of a sock.
This second use is shown by the stitch diagram in
In this second intended use, the knit necessarily comprises a weft yarn.
As described previously, the weft yarn (7) is used to impart special properties to the knit (1), and may be of any type suitable for this purpose. In particular, the addition of a weft yarn makes it possible to control the elasticity of a textile item, especially a compression and/or support item, by imparting greater elastic strength. This may be a single-coated or double-coated yarn, for example, with an elastane core yarn and polyamide coating yarns.
In a preferred embodiment, the core yarn is an elastane yarn with a titre of 310 dtex, double-twisted polyamide coating yarns with a titre of 22 dtex, comprising 20 filaments, and with false twist. In this embodiment, the two coating yarns are preferably reversed in their false-twist directions.
The weft yarn (T) is inserted between each row of stitches, by creating a float (i) that corresponds to the needle that knitted a load (c) on the first row of stitches (M1). As a result, the weft yarn lies between the first row of stitches (M1) and the second row of stitches, (M2) and also between the second row of stitches (M2) and the first row of stitches (M1). The weft yarn is picked (T) only every other needle. This thus creates a columnar alignment between the load (c) of the first row of stitches (M1) and the float (i) of the weft row (T). The weft yarn floats (i) are created in the same columns on each weft row (T). In other words, the floats are created in the same columns, on each weft row (T), such that their alignment results in a ribbed appearance and further strengthens the knit.
This specific knitting technique, based on the needle selections of rows M1, M2 and T as described previously, allows the added, plated yarn from the off-cuts of the second row of stitches (M2) to stand out on the outside of the finished textile article, thus improving strength.
This advantage is illustrated schematically in
In this figure, it can be seen that the majority of the reinforcement yarn can be knitted with the stitch-forming yarn of the second row of stitches (M2). The reinforcing yarn therefore stands out visually on this side of the knit. This is due, as previously described, to the selection of stitch-type and load-type needles in the first row of stitches (M1), in combination with the placement of the weft yarn (7) inside the sinker loops of the second row of stitches (M2).
In this figure, most of the stitch-forming yarn from the first row of stitches (M1) and the weft yarn (7) are visible. The stitch-forming yarn of the first row of stitches (M1) and the weft yarn (7) therefore stand out visually on this side of the knit.
Thus, the selection of particular needles for the weft yarn and the selective placement of loads every other needle on the stitch-forming yarn of the first row of stitches (M1), allow the reinforcing yarn knitted in plating M2 to stand out on the outside of the knit to provide greater strength.
The textile item is necessarily a compression and/or support item, for example, for medical purposes, because the constituent knit (1) of the item comprises a weft yarn (7).
The textile item (3) produced in this way is reinforced in the zones most subject to wear and tear. The textile item (3) according to the invention therefore has a longer service life, without compromising its manufacturing cost, because the knitting method according to the invention does not impact production rates or reject rates, unlike methods of the prior art.
Both when knitting dense zones for aesthetic purposes and when knitting dense zones to reinforce the knit, clearly, those skilled in the art may adapt the number and shape of the dense zones (2) according to the type of knit and item they wish to produce.
In a variant not shown in connection with the two intended uses of dense zones, the combination of needle selections may involve another alternation of stitch rows and weft rows. For example, the rhythm may be:
The yarns used may be adapted to the intended use of the knit (1). Their counts, compositions and material(s) may therefore be different.
Furthermore, the technical characteristics of the various embodiments and variants mentioned above can be combined in their entirety or only in part. Thus, the method and the knit may be adapted depending on the desired cost, functions and performance.
Number | Date | Country | Kind |
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FR2107610 | Jul 2021 | FR | national |
Filing Document | Filing Date | Country | Kind |
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PCT/EP2022/069512 | 7/12/2022 | WO |