阅读说明：本技术 一种3d织物及其制备方法 (3D fabric and preparation method thereof ) 是由 王姜 王山水 汤方明 王丽丽 郁秀峰 张元华 于 2020-12-11 设计创作，主要内容包括：本发明涉及一种3D织物及其制备方法,3D织物是由经纱和纬纱交织即形成的表面不为平面的机织物,且机织物上各处的经密相同,纬密相同；机织物上的所有经纱与任一呈弯曲状的经纱所在的平面平行；机织物上的所有纬纱与任一呈弯曲状的纬纱所在的平面平行；制备方法为：首先根据3D织物的立体结构,确定织造参数：第i次打纬时第j根经纱的送经量和第i次打纬时第j根经纱对应的综丝的综眼高度,然后在3D织物织造时对应的织口至第一排综丝区域内放置相应的栅格状支撑体进行织造,制得3D织物。本发明方法适用范围广泛,可直接织造出曲面形态的织物,制得的3D织物具有一次成型、结构无中断、密度可控以及曲面复杂的优点。(The invention relates to a 3D fabric and a preparation method thereof, wherein the 3D fabric is a woven fabric with a non-planar surface formed by interweaving warp yarns and weft yarns, and the warp density and the weft density of each part of the woven fabric are the same; all warp yarns on the woven fabric are parallel to the plane where any warp yarn in a bent shape is located; all the weft yarns on the woven fabric are parallel to the plane where any one of the bent weft yarns is located; the preparation method comprises the following steps: firstly, determining weaving parameters according to the three-dimensional structure of the 3D fabric: and placing a corresponding grid-shaped support body in the area from the weaving opening to the first row of heddles corresponding to the 3D fabric for weaving to obtain the 3D fabric. The method has wide application range, can directly weave the fabric with the curved surface shape, and the prepared 3D fabric has the advantages of one-step forming, no interruption of the structure, controllable density and complex curved surface.)

The 3D fabric is characterized in that the 3D fabric is a woven fabric with a non-planar surface formed by interweaving warp yarns and weft yarns;

the warp density and the weft density of each part of the woven fabric are the same;

all warp yarns on the woven fabric are parallel to a plane where any warp yarn in a bent shape is located, and all weft yarns on the woven fabric are parallel to a plane where any weft yarn in a bent shape is located.

2. The 3D fabric of claim 1, wherein the warp yarns are of more than one gauge and the weft yarns are of more than one gauge.

3. The 3D fabric of claim 2, wherein each warp yarn has a uniform thickness and each weft yarn has a uniform thickness.

4. The 3D fabric of claim 2, wherein each warp yarn has the same or different cross-sectional shape at different locations and each weft yarn has the same or different cross-sectional shape at different locations.

5. The 3D fabric of claim 2, wherein each warp yarn corresponds to more than one material and each weft yarn corresponds to more than one material.

6. The 3D fabric of claim 1, wherein the surface is not planar means that the surface is one or more of a positive gaussian curvature surface, a negative gaussian curvature surface, and a zero gaussian curvature surface and is not a single plane.

7. The 3D fabric of claim 1, wherein the weave structure of the woven fabric is a plain weave, a twill weave, a satin weave, a basket weave, a crowfoot weave, or a satin reinforcement weave.

8. The 3D fabric of claim 1, wherein the woven fabric is a single layer or more than two layers.

9. A method of making a 3D fabric according to any of claims 1 to 8, characterized by: firstly, determining weaving parameters according to the three-dimensional structure of the 3D fabric: the heddle eye height H of the heddle corresponding to the jth warp yarn in the ith beating-up_ijI is 1,2, m, j is 1,2, n, m is the number of beating-up times, n is the number of warp yarns, and then corresponding grid-shaped supporting bodies are placed in the regions from the corresponding cloth fell to the first row of heddles for weaving when the 3D fabric is woven, so that the 3D fabric is prepared;

H_ijis the ith weftThe height of the intersection point of the yarn and the jth warp yarn relative to a plane formed by the front beam and the rear beam;

the upper surface of the grid-shaped supporting body is the same as the curved surface of the 3D fabric and is formed by connecting a plurality of thin plates which are arranged at equal intervals, the thickness direction of the thin plates is the same as the weft yarn direction, the interval between every two adjacent thin plates is the interval between every two adjacent reed dents of the reed, and the thickness of each thin plate is smaller than 1/3 of the interval between every two adjacent reed dents of the reed.

10. The method of claim 9, wherein the weaving parameters further include a let-off Q of the jth warp yarn at the ith beat-up_ijI is 1,2,. m, j is 1,2,. n, m is the number of beating-up times, n is the number of warp yarns;

Q_ijis the length/(1-warp shrinkage) of every j warp yarns between the ith and (i-1) th weft yarns.

11. The method for preparing the 3D fabric according to claim 9, wherein the weaving parameters are determined according to the three-dimensional structure of the 3D fabric by: constructing a structural equivalent image consisting of warp-wise intersecting lines and weft-wise intersecting lines according to the warp yarns and the weft yarns of the 3D fabric, wherein the warp-wise intersecting lines correspond to the warp yarns, and the weft-wise intersecting lines correspond to the weft yarns;

Q_ijthe calculation formula of (a) is as follows: q_ij＝L_ij(1-warp shrinkage);

wherein L is_ijThe length of each j warp intersecting lines between the ith weft intersecting line and the (i-1) th warp intersecting line on the structural equivalent image;

H_ijthe calculation formula of (a) is as follows: h_ijReference heddle eye height + delta_ij；

The standard heddle eye height is the heddle eye height of a heddle corresponding to the 1 st warp yarn in the 1 st beating-up in weaving; delta_ijThe height of the intersection point of the ith latitudinal intersection line and the jth longitudinal intersection line on the structural equivalent image is compared with the reference plane; the reference surface is a horizontal plane of an intersection point of the 1 st latitudinal intersection line and the 1 st longitudinal intersection line on the structural equivalent image.

12. The method of claim 10, wherein each warp yarn is independently warp fed during weaving; and adjusting the heddle eye height of the heddle corresponding to each warp yarn before each beating-up.

13. The method for preparing the 3D fabric according to claim 11, wherein the adjustment of the height of the heddle eyes of the heddles corresponding to each warp yarn before each beating-up is realized by independently connecting different heddles with different lifting mechanisms and controlling the lifting of the heddles by a certain height;

the independent let-off of each warp yarn is realized by connecting different warp yarns with different let-off mechanisms respectively and independently and controlling the let-off amount of each warp yarn.

Technical Field

The invention belongs to the technical field of spinning, and relates to a 3D fabric and a preparation method thereof.

Background

Woven fabrics are textile materials with a long development history, and often integrate the properties of flexibility, strength, air permeability and the like. At the present time, more and more types of woven fabrics are increasingly used in the fields of industry, clothing and decoration, and more fabrics are adopted, wherein the demand of 3D fabrics is increasing, especially in the fields of composite material direction, personalized garment customization direction and the like.

At the present stage, different technical means can be adopted to realize the preparation of the 3D woven fabric aiming at different use occasions, the three-dimensional shape of the existing fabric is generally formed by secondary processing of a plane fabric, the processed three-dimensional shape often does not have the characteristics of continuous structure, controllable density and complex curved surface, and any defect is insufficient to enable the three-dimensional shape to be used as an effective shape structure for industrial application. Among them, the most common method is to cut the plane fabric and sew, rivet or bond the fabric according to a specific shape, but the application performance of the product is affected by the structural discontinuity caused by the damage to the fabric; in addition, in the prior art, yarns with different heat shrinkage rates are also used for weaving a plane fabric, the plane fabric contains yarns with different heat shrinkage rates, after the plane fabric is subjected to heat treatment, the yarns with large heat shrinkage rates shrink, and the yarns with small heat shrinkage rates bulge to form three-dimensional shapes such as folds and the like.

Therefore, it is highly desirable to develop a 3D fabric and a method for preparing the same, which has the advantages of one-step forming, no interruption in structure, controllable density, and complex curved surface.

Disclosure of Invention

The invention aims to solve the problems in the prior art and provides a 3D fabric and a preparation method thereof.

The 3D fabric consists of a curved surface area or a curved surface area and a plane area, and the preparation idea is approximately as follows: when weaving the plane area of the 3D fabric, interweaving the warp yarns according to a normal weaving process of the woven fabric; when weaving the curved surface area, according to the form of the curved surface area, the height of the heddle eyes is adjusted, the warp let-off amount of the warp yarns participating in the interweaving of the curved surface area is increased, and the warp let-off amount increase of the warp yarns in the curved surface areas with different heights is different, and the general principle is as follows: the height of the heddle eyes penetrated by the warp yarns participating in the weaving of the curved surface area is different from that of the heddle eyes penetrated by the warp yarns participating in the weaving of the plane area, and the height of the heddle eyes penetrated by the warp yarns participating in the weaving of the upper area of the curved surface area is higher than that of the heddle eyes penetrated by the warp yarns participating in the weaving of the lower area of the curved surface area; the heights of the front beam and the back beam are consistent and are kept unchanged in the weaving process, and the warp yarns and the weft yarns are interwoven to form a plane area when the brown eyes of the warp yarns, which are returned to the leveling position, are 0 relative to the height of the front beam or the back beam, and the warp yarns and the weft yarns are interwoven to form a curved area when the brown eyes of the warp yarns, which are returned to the leveling position, are not 0 relative to the height of the front beam or the back beam.

The 3D shape of the 3D fabric is obtained by weaving and not by secondary processing, so that the defects that the processed three-dimensional shape does not have the characteristics of continuous structure, controllable density and complex curved surface due to secondary processing are effectively overcome.

In order to achieve the purpose, the technical scheme adopted by the invention is as follows:

the 3D fabric is a woven fabric with a non-planar surface formed by interweaving warp yarns and weft yarns, and the surface is a surface obtained by neglecting the micro-fluctuation of the woven fabric surface caused by interweaving the warp yarns and the weft yarns; the warp density and the weft density of each part of the single-layer plain woven fabric are the same; all warp yarns on the woven fabric are parallel to a plane where any warp yarn in a bent shape is located, and all weft yarns on the woven fabric are parallel to a plane where any weft yarn in a bent shape is located.

As a preferred technical scheme:

the 3D fabric as described above, the warp yarns are of one or more gauges and the weft yarns are of one or more gauges; the specification of the yarn refers to the thickness of a bundle of yarn, the thickness of single fibers in the yarn, the cross-sectional shape, the material, even the twist, the color and the like.

The 3D fabric has the advantages that the thickness of each warp yarn is uniform, and the thickness of each weft yarn is uniform; when the 3D fabric is prepared by adopting the prior art (namely, the projection area of the planar fabric to be processed is kept unchanged, and simultaneously, the warp and weft yarns set as the curved surface area are stretched to a certain degree), the condition of uneven density is very easy to occur in the curved surface area, namely, the thickness of the same warp yarn or weft yarn at different positions is inconsistent.

In the 3D fabric, the cross-sectional shape of each warp yarn at different positions is the same or different, and the cross-sectional shape of each weft yarn at different positions is the same or different.

In the 3D fabric, each warp corresponds to more than one material, and each weft corresponds to more than one material; the material of the yarn depends on the monofilaments in the yarn, and when the materials of all the monofilaments in one yarn are single and the same, the yarn corresponds to one material; otherwise, the yarn is corresponding to more than two materials.

In the 3D fabric, the surface being not a plane means that the surface is one or more of a positive gaussian curvature surface, a negative gaussian curvature surface, and a zero gaussian curvature surface, and is not a single plane; the structure of the 3D fabric can be adjusted at will, namely the shape of the surface is diversified, the fabric can be adjusted according to actual requirements, for example, the fabric can be woven with the body and the wings of an unmanned aerial vehicle, the body and the wings of the unmanned aerial vehicle can be woven by adopting a fabric-based composite material, the planar fabric is generally endowed with a mould in the current stage of preparation through cutting or folding, and a subsequent resin curing process is carried out The strength of the artificial limb is reduced to a certain extent by means of later-stage measures such as cutting and the like, the 3D fabric can realize the integrated weaving of artificial limbs in various forms, the woven artificial limb fabric can be directly attached to a base body for curing treatment, and the structure of the 3D fabric is limited because a plurality of types of curved surfaces cannot be obtained by equivalent topology of a plane structure in the prior art.

As described above, the weave structure of the woven fabric is plain weave, twill weave, satin weave, basket weave, broken twill weave or satin reinforcement weave, and the weave structure of the woven fabric of the present invention is not limited, and only some common weave structures are listed here.

As described above, the woven fabric has a single-layer or two-layer structure.

The invention also provides a method for preparing the 3D fabric, which comprises the following steps of firstly determining weaving parameters according to the three-dimensional structure of the 3D fabric: the heddle eye height H of the heddle corresponding to the jth warp yarn in the ith beating-up_ijI is 1,2, m, j is 1,2, n, m is the number of beating-up times, n is the number of warp yarns, and then corresponding grid-shaped supporting bodies are placed in the regions from the corresponding cloth fell to the first row of heddles for weaving when the 3D fabric is woven, so that the 3D fabric is prepared;

H_ijthe height of the intersection point of the ith weft yarn and the jth warp yarn relative to a plane formed by the front beam and the rear beam;

the upper surface of the grid-shaped supporting body is the same as the curved surface of the 3D fabric and is formed by connecting a plurality of thin plates which are arranged at equal intervals, the thickness direction of the thin plates is the same as the weft yarn direction, the interval between every two adjacent thin plates is the interval between every two adjacent reed dents of the reed, and the thickness of each thin plate is smaller than 1/3 of the interval between every two adjacent reed dents of the reed.

As a preferred technical scheme:

in the preparation method of the 3D fabric, the weaving parameters further comprise the let-off quantity Q of the jth warp yarn in the ith beating-up_ijI is 1,2,. m, j is 1,2,. n, m is the number of beating-up times, n is the number of warp yarns;

Q_ijis the length/(1-warp shrinkage) of every j warp yarns between the ith and (i-1) th weft yarns.

According to the preparation method of the 3D fabric, the weaving parameters are determined according to the three-dimensional structure of the 3D fabric by the following steps: constructing a structural equivalent image consisting of warp-wise intersecting lines and weft-wise intersecting lines according to the warp yarns and the weft yarns of the 3D fabric, wherein the warp-wise intersecting lines correspond to the warp yarns, and the weft-wise intersecting lines correspond to the weft yarns;

Q_ijthe calculation formula of (a) is as follows: q_ij＝L_ij(1-warp shrinkage);

wherein L is_ijThe length of each j warp intersecting lines between the ith weft intersecting line and the (i-1) th warp intersecting line on the structural equivalent image;

H_ijthe calculation formula of (a) is as follows: h_ijReference heddle eye height + delta_ij；

Wherein, the standard heddle eye height is the heddle eye height (an arbitrary set value during weaving) of the heddle corresponding to the 1 st warp yarn during the 1 st beating-up during weaving; delta_ijThe height of the intersection point of the ith latitudinal intersection line and the jth longitudinal intersection line on the structural equivalent image is compared with the reference plane; the reference surface is a horizontal plane of an intersection point of the 1 st latitudinal intersection line and the 1 st longitudinal intersection line on the structural equivalent image.

The structure equivalent image is an expression image used for describing the shape of the main body structure and calculating the length of the warp and weft yarns; the longitudinal intersecting line and the latitudinal intersecting line are respectively intersecting lines of orthogonal plane families and planes, each orthogonal plane family is composed of a group of planes A which are parallel to each other and another group of planes B which are parallel to each other, the planes A and the planes B are mutually vertical, at least one point on each plane is not on the reference plane, the reference plane or the plane parallel to the reference plane in the structure equivalent image corresponds to the above-mentioned 'plane area', and the plane except the reference plane and the plane parallel to the reference plane in the structure equivalent image corresponds to the above-mentioned 'curved area';

in the preparation method of the 3D fabric, during weaving, independent warp feeding is carried out on each warp yarn (the independent warp feeding can convey the warp yarn with a specific length at any time and keep the tension unchanged); and adjusting the heddle eye height of the heddle corresponding to each warp yarn before each beating-up.

According to the preparation method of the 3D fabric, the heddle eye height of the heddle corresponding to each warp yarn is adjusted before each beating-up, different heddles are independently connected with different lifting mechanisms respectively, and the lifting of each heddle is controlled to be carried out by a certain height;

the independent let-off of each warp yarn is realized by connecting different warp yarns with different let-off mechanisms respectively and independently and controlling the let-off amount of each warp yarn.

The form of the weft yarn is changed along with the warp yarn in the weaving process of the woven fabric, the height of the heddle eye penetrated by the warp yarn is higher, and the height of the woven fabric is higher, so that the warp let-off quantity of each warp yarn and the heddle eye height of the heddle corresponding to each warp yarn before each beating-up action are determined through the structural equivalent image of the 3D fabric, and the 3D fabric which is consistent with the preset structure can be obtained by weaving according to the height.

In the prior art, a weaving method is adopted to weave a 3D fabric, a complex fabric weave structure is often adopted, different types of woven fabrics such as a multilayer fabric, a spacer fabric, a towel fabric and a napped fabric can be prepared, the overall or local increase of the fabric in the thickness direction is realized only by controlling the interweaving rule, length or number of warp and weft yarns, and the preparation of the equal-thickness fabric with a 3D form cannot be realized. The preparation process of the 3D fabric does not adopt a complex fabric weave structure, so that the defect of low fabric thickness consistency caused by the adoption of the complex fabric weave structure is effectively overcome.

The invention mechanism is as follows:

the three-dimensional shape of the existing fabric is generally formed by carrying out secondary processing on a plane fabric, the processed three-dimensional shape often does not have the characteristics of continuous structure, controllable density and complex curved surface, and any defect is insufficient to enable the processed three-dimensional shape to be used as an effective shape structure for industrial application. The 3D fabric has the advantages of one-step forming, no interruption of structure, controllable density and complex curved surface; its primary molded body is now: the warp yarns and the weft yarns can be interwoven in the curved surface area by controlling the warp let-off amount of a single warp yarn and the conveying length of a single weft yarn; the structure is embodied without interruption in that: the whole fabric is formed by interweaving continuous warp yarns and weft yarns, and the warp yarns and the weft yarns of the curved surface area and the plane area of the fabric are continuous; the density of the composite material is controllable as follows: the warp density and the weft density in the projection unit length of the fabric curved surface area and the warp density and the weft density in the plane area can be quantitatively regulated and controlled by controlling the reed number and the fabric curling speed; the curved surface is complexly embodied as follows: when the three-dimensional modeling is realized by secondary processing of curved surfaces which are not equivalent to a planar structure in geometric topology, larger deviation can occur, particularly the three-dimensional modeling of smooth curved surfaces is difficult to fully express, and the 3D fabric can be realized by controlling the warp yarn let-off amount, the weft yarn conveying length, the lifting heald stroke and placing corresponding grid-shaped supporting bodies in the weaving area of the 3D fabric.

Specifically, the grid-shaped support body adopted by the invention is formed by arranging and combining a plurality of plane sheets at equal intervals, when in weaving, the thickness direction of the sheets is the same as the weft yarn direction, the sheets can smoothly enter between reed dents, the interval between the adjacent sheets is the interval between the adjacent reed dents of the reed, and the thickness of each sheet is smaller than 1/3 of the interval between the adjacent reed dents of the reed, so that the existence of the sheets is ensured not to influence the interweaving of yarns, the weft yarns can be arranged at equal intervals when in beating, the weft yarns are linear in the projection direction of the prepared fabric, and when the weft yarns are wound at a constant speed, the weft yarn density is uniform; the warp density is controlled by a reed, and the warp density can be ensured to be consistent by a conventional reed and a standard drafting process.

Moreover, when weaving the curved surface area, according to the form of the curved surface area, through the control of the heddle eye height and the let-off quantity, and the let-off quantity increment of the warp yarn in the curved surface area with different heights is different, the general principle is as follows: the height of the heddle eyes penetrated by the warp yarns participating in the weaving of the curved surface area is different from that of the heddle eyes penetrated by the warp yarns participating in the weaving of the plane area, and the height of the heddle eyes penetrated by the warp yarns participating in the weaving of the upper area of the curved surface area is higher than that of the heddle eyes penetrated by the warp yarns participating in the weaving of the lower area of the curved surface area; the heights of the front beam and the back beam are consistent and are kept unchanged in the weaving process, when the height of a brown eye, corresponding to the height of the front beam or the back beam, of the warp yarn is 0 when the warp yarn is returned to the heald flat position, the warp yarn and the weft yarn are interwoven to form a plane area, and when the height of the brown eye, corresponding to the height of the front beam or the back beam, of the warp yarn is not 0 when the warp yarn is returned to the heald flat position, the warp yarn and the weft yarn are interwoven to form a curved surface area.

In addition, the grid-shaped support body adopted in the method is simple to prepare, and the special-shaped roll curling method is used for preparing the three-dimensional fabric, and the special-shaped roll corresponding to the action of the grid-shaped support body is in a three-dimensional shape, so that the processing is very complex.

Advantageous effects

(1) According to the preparation method of the 3D fabric, warp and weft yarns can be interwoven on the curved surface by controlling the warp yarn let-off amount, the weft yarn conveying length and the lifting heddle stroke, and the 3D fabric with a specific curved surface form can be prepared;

(2) the preparation method of the 3D fabric can solve the problems of raw material waste, complicated working procedures and lack of functionality in the three-dimensional modeling of the fabric in the prior art, and particularly solves the one-step molding problem of the three-dimensional modeling which is not equivalent to the plane topology;

(3) the 3D fabric can avoid side effects caused by folding, cutting, sewing and other methods used in three-dimensional modeling of the plane fabric, and has the advantages of uniform structure, no defect in using effect, controllable density, uniform thickness and strong complex curved surface molding.

Drawings

FIG. 1 is a structural equivalent image of a 3D fabric;

fig. 2 is a schematic structural view of the 3D fabric corresponding to fig. 1;

FIG. 3 is a schematic side view of a 3D fabric as it is woven;

FIG. 4 is a schematic top view of a 3D fabric as it is woven;

FIG. 5 is a schematic front view of a 3D fabric as it is woven;

wherein, the warp direction intersecting line is 1, the weft direction intersecting line is 2, the warp yarn is 3 at the plane, the warp yarn is 4 at the curved surface, the weft yarn is 5 at the plane, and the weft yarn is 6 at the curved surface.

Detailed Description

The invention will be further illustrated with reference to specific embodiments. It should be understood that these examples are for illustrative purposes only and are not intended to limit the scope of the present invention. Further, it should be understood that various changes or modifications of the present invention may be made by those skilled in the art after reading the teaching of the present invention, and such equivalents may fall within the scope of the present invention as defined in the appended claims.

The 3D fabric is a woven fabric with a non-planar surface formed by interweaving warp yarns and weft yarns, and the warp density and the weft density of all positions on the woven fabric are the same;

all warp yarns on the woven fabric are parallel to a plane where any warp yarn in a bent shape is located; all the weft yarns on the woven fabric are parallel to the plane where any one of the bent weft yarns is located;

the warp yarns are of more than one specification, and the weft yarns are of more than one specification; the thickness of each warp yarn is uniform or uneven, and the thickness of each weft yarn is uniform or uneven; the cross section shape of each warp yarn at different positions is the same or different, and the cross section shape of each weft yarn at different positions is the same or different; each warp corresponds to more than one material, and each weft corresponds to more than one material;

the surface is not a plane, namely the surface is more than one of a positive Gaussian curvature surface, a negative Gaussian curvature surface or a zero Gaussian curvature surface and is not a single plane;

the weave structure of the woven fabric is plain weave, twill weave, satin weave, basket weave, broken twill weave or satin reinforcement weave; the woven fabric is of a single-layer or more than two-layer structure;

the method for preparing the 3D fabric comprises the following steps of firstly, determining weaving parameters according to the three-dimensional structure of the 3D fabric: the ith timeLet-off Q of jth warp during beating-up_ijThe heddle eye height H of the heddle corresponding to the jth warp yarn in the ith beating-up_ijI is 1,2, m, j is 1,2, n, m is the number of beating-up times, n is the number of warp yarns, and then corresponding grid-shaped supporting bodies are placed in the regions from the corresponding cloth fell to the first row of heddles for weaving when the 3D fabric is woven, so that the 3D fabric is prepared;

Q_ijthe length/(1-warp shrinkage) of every j warp yarns between the ith and (i-1) th weft yarns;

H_ijthe height of the intersection point of the ith weft yarn and the jth warp yarn relative to a plane formed by the front beam and the rear beam;

the method for determining the weaving parameters according to the three-dimensional structure of the 3D fabric can also comprise the following steps: constructing a structural equivalent image consisting of warp-wise intersecting lines and weft-wise intersecting lines according to the warp yarns and the weft yarns of the 3D fabric, wherein the warp-wise intersecting lines correspond to the warp yarns, and the weft-wise intersecting lines correspond to the weft yarns; q_ijThe calculation formula of (2) is as follows: q_ij＝L_ij(1-warp shrinkage); wherein L is_ijThe length of each j warp intersecting lines between the ith weft intersecting line and the (i-1) th warp intersecting line on the structural equivalent image; h_ijThe calculation formula of (2) is as follows: h_ijReference heddle eye height + delta_ij(ii) a The standard heddle eye height is the heddle eye height of a heddle corresponding to the 1 st warp yarn in the 1 st beating-up in weaving; delta_ijThe height of the intersection point of the ith latitudinal intersection line and the jth longitudinal intersection line on the structural equivalent image is compared with the reference plane; the reference plane is a horizontal plane of an intersection point of the 1 st latitudinal intersection line and the 1 st longitudinal intersection line on the structural equivalent image;

the upper surface of the grid-shaped supporting body is the same as the curved surface of the 3D fabric and is formed by connecting a plurality of thin plates which are arranged at equal intervals, the thickness direction of the thin plates is the same as the weft yarn direction, the interval between every two adjacent thin plates is the interval between every two adjacent reed dents of the reed, and the thickness of each thin plate is smaller than 1/3 of the interval between every two adjacent reed dents of the reed.

During weaving, each warp yarn is independently let-off; adjusting the heddle eye height of the heddle corresponding to each warp yarn before each beating-up; adjusting the height of the heddle eyes of the heddles corresponding to each warp yarn before each beating-up is realized by independently connecting different heddles with different lifting mechanisms and controlling the lifting of the heddles to a certain height; the independent let-off of each warp yarn is realized by connecting different warp yarns with different let-off mechanisms respectively and independently and controlling the let-off amount of each warp yarn.

To illustrate the implementation of the present invention in more detail, a 3D fabric as shown in fig. 2 is prepared, the 3D fabric is formed by interweaving a plane warp yarn 3, a curve warp yarn 4, a plane weft yarn 5 and a curve weft yarn 6, the 3D fabric has a curve area, and the other areas are plane areas; the height of a curved surface area of the 3D fabric is 3cm, the orthographic projection of the curved surface area is an ellipse, the length of a long axis of the ellipse is 4cm, the length of a short axis of the ellipse is 3cm, the lateral projection of the curved surface area is a semicircle (when the lateral corresponds to the warp direction, the projection diameter is 3cm, when the lateral corresponds to the weft direction, the projection is an ellipse, the length of the long axis is 4cm, and the length of the short axis is 3 cm); the warp tightness of the 3D fabric is 70%, and the weft tightness is 70%;

the preparation steps are as follows:

(1) the raw materials were prepared as follows in table 1:

TABLE 1 warp and weft Specifications

(2) As shown in fig. 1, according to the warp and weft yarns of the 3D fabric (plain weave), the number of which is 50 × 50, a structural equivalent image composed of warp intersecting lines 1 and weft intersecting lines 2 is constructed, wherein the jth warp intersecting line 1 corresponds to the jth warp yarn, and the ith weft intersecting line 2 corresponds to the ith weft yarn; wherein, i is 1,2,. 50, j is 1,2,. 50;

(3) determining weaving parameters: calculating the let-off quantity Q of the jth warp yarn in the ith beating-up according to the following formula_ij：

Q_ij＝L_ij(1-warp shrinkage);

wherein L is_ijThe length of each j warp intersecting lines between the ith weft intersecting line and the (i-1) th warp intersecting line on the structural equivalent image; the warp shrinkage is 5%;

the calculated let-off amount is shown in the following tables 2-1 and 2-2;

TABLE 2-1 let-off Q of jth warp yarn at ith beat-up_ij/(mm)

TABLE 2-2 let-off Q of jth warp yarn at ith beat-up_ij/(mm)

Calculating the heddle eye height H of the heddle corresponding to the jth warp yarn in the ith beating-up according to the following formula_ij；

H_ijReference heddle eye height + delta_ij；

Wherein, the reference heddle eye height is the heddle eye height (value is 0) of the heddle corresponding to the 1 st warp yarn during the 1 st beating-up in weaving; delta_ijThe height of the intersection point of the ith latitudinal intersection line and the jth longitudinal intersection line on the structural equivalent image is compared with the reference plane; the reference plane is a horizontal plane of an intersection point of the 1 st latitudinal intersection line and the 1 st longitudinal intersection line on the structural equivalent image;

the height of the heddle eyes is calculated and is shown in the following tables 3-1 and 3-2;

TABLE 3-1 heddle eye height H of heddle corresponding to jth warp yarn at ith beating-up_ij/(mm)

TABLE 3-2 heddle eye height H of heddle corresponding to jth warp yarn at ith beating-up_ij/(mm)

(4) Weaving: weaving according to the raw materials in table 1 and weaving parameters in tables 2 and 3, wherein fig. 3-5 are schematic weaving diagrams of the 3D fabric, which show the interweaving process of the warp yarns 3 at the plane, the warp yarns 4 at the curved surface, the weft yarns 5 at the plane and the weft yarns 6 at the curved surface.

The 3D fabric can realize the primary weaving of the complex curved surface form of the fabric, and overcomes the defects of discontinuous warp and weft yarns, non-uniform warp and weft density and defective use effect caused by working procedures such as folding, cutting, sewing and the like adopted in secondary three-dimensional modeling.