Laptop upper cover plate containing fabric and preparation method thereof
阅读说明：本技术 一种含织物的笔记本电脑上盖板及其制备方法 (Laptop upper cover plate containing fabric and preparation method thereof ) 是由 汤方明 范红卫 黄瑶 孙晓华 付恒岩 于 2020-12-11 设计创作，主要内容包括：本发明涉及一种含织物的笔记本电脑上盖板及其制备方法,笔记本电脑盖板主要由盖板用布和热固性环氧树脂组成；盖板用布是由经纱和纬纱交织即形成的单层平纹机织物；单层平纹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；所有纬纱与任一呈弯曲状的纬纱所在的平面平行；且单层平纹机织物上各处的经密相同,纬密相同；制备方法为：采用平纹织造工艺,制得盖板用布,采用模具注塑方法,将盖板用布放置模具中,用热固性环氧树脂固化,制得笔记本电脑上盖板；本发明的一种含织物的笔记本电脑上盖板,十分符合当下的审美观念,在电脑上盖板的各处,均不存在结构缺陷,电脑上盖板的边角处的承载能力更强。(The invention relates to a fabric-containing upper cover plate of a notebook computer and a preparation method thereof, wherein the upper cover plate of the notebook computer mainly comprises cover plate cloth and thermosetting epoxy resin; the cover plate cloth is a single-layer plain woven fabric formed by interweaving warp yarns and weft yarns; all warps on the single-layer plain woven fabric are parallel to the plane of any bent warp; all the weft yarns are parallel to the plane where any one of the bent weft yarns is located; the warp density and the weft density of each part of the single-layer plain woven fabric are the same; the preparation method comprises the following steps: preparing cloth for the cover plate by adopting a plain weaving process, placing the cloth for the cover plate in a mould by adopting a mould injection molding method, and curing by using thermosetting epoxy resin to prepare the upper cover plate of the notebook computer; the upper cover plate of the notebook computer containing the fabric provided by the invention is quite in line with the current aesthetic concept, no structural defects exist at all positions of the upper cover plate of the computer, and the bearing capacity of the corners of the upper cover plate of the computer is stronger.)
1. The upper cover plate of the notebook computer containing the fabric is characterized by mainly comprising cloth for the cover plate and thermosetting epoxy resin; the content of the thermosetting epoxy resin is 25-30 wt%;
the cover plate cloth is a single-layer plain woven fabric formed by interweaving warp yarns and weft yarns; the surface of the single-layer plain weave fabric comprises a curved surface; the generatrix of the curve surface consists of a line segment I and an arc line I formed by extending from two ends of the line segment I, and the symmetry axis of the generatrix is a perpendicular bisector of the line segment I; the lead of the curve surface consists of a line segment II and an arc line II formed by extending from one end of the line segment II; the orthographic projection surface of the curve surface is rectangular, the long side of the rectangle corresponds to the orthographic projection line of the bus, and the short side corresponds to the orthographic projection line of the lead;
all warps on the single-layer plain woven fabric are parallel to the plane of any bent warp; all weft yarns on the single-layer plain woven fabric are parallel to the plane where any one bent weft yarn is located; the warp density and the weft density of each part of the single-layer plain woven fabric are the same.
2. The upper cover plate of a notebook computer containing a fabric according to claim 1, wherein the circle where the circular arc line I is located and the circle where the circular arc line II is located have the same diameter;
warp density lambda of single layer plain woven fabricWarp beam5 to 7 pieces/10 cm, weft density lambdaWeft yarn5-7 roots/10 cm;
the warp yarns and the weft yarns are 20k of polyacrylonitrile-based carbon fibers, the modulus of the polyacrylonitrile-based carbon fibers is 230-240 GPa, and the strength is 3500-3600 MPa.
3. The upper cover plate for a notebook computer comprising a woven fabric according to claim 2, wherein the fit coefficient of the cover plate cloth is 98.9% or more.
4. The notebook computer upper cover plate containing the fabric according to claim 3, wherein the bending strength of the notebook computer upper cover plate is 280 to 350MPa, and the impact strength reaches 62.3 to 74.2 KJ-m-2。
5. The method for preparing the upper cover plate of the notebook computer comprising the fabric according to any one of claims 1 to 4, comprising the steps of:
(1) weaving the cloth for the cover plate: adopting a plain weaving process, and arranging a fabric weaving area for the cover plate, wherein the fabric weaving area for the cover plate comprises a curved surface of the single-layer plain woven fabric and an extension surface of the curved surface extending towards the periphery of the single-layer plain woven fabric, and when each weave point is formed, setting the corresponding heddle eye height to prepare the fabric for the cover plate;
the corresponding calculation method of the height of the heddle eye comprises the following steps:
(1.1) when wi＜W1Or wi＞L-W3Or wj＜W2Or wj＞D-W4When h is presentij＝0；
(1.2) when W1≤wi≤W1+R1sinθ1And W is2≤wj≤W2+R2sinθ2When the temperature of the water is higher than the set temperature,
if it isThen h isij＝0；
If it isThen
(1.3) when W1≤wi≤W1+R1sinθ1And D-W4-R2sinθ2≤wj≤D-W4When the temperature of the water is higher than the set temperature,
if it isThen h isij＝0；
If it isThen
(1.4) when W1≤wi≤W1+R1sinθ1And W is2+R2sinθ2＜wj＜D-W4-R2sinθ2When the temperature of the water is higher than the set temperature,
(1.5) when W1+R1sinθ1＜wi≤L-W3When the temperature of the water is higher than the set temperature,
if W2≤wj≤W2+R2sinθ2Then, then
If D-W4-R2sinθ2≤wj≤D-W4Then, then
If W2+R2sinθ2＜wj＜D-W4-R2sinθ2Then h isij＝R2(1-cosθ2)；
wi＝i×10/λWeft yarn；
vj＝j×10/λWarp beam；
Wherein h isijThe heddle eye height, s, of the weave point formed by the ith weft yarn and the jth warp yarn in weaving the fabric weaving area for the cover plateijWhen weaving the fabric weaving area for the cover plate, the let-off amount of a weave point formed by the ith weft yarn and the jth warp yarn is i-1, the.. m, j-1, the.. n, wherein m is the number of beating-up times, and n is the number of warp yarns; r1Is the radius of the circle on which the circular arc line I is located, theta1Is the central angle, R, corresponding to the circular arc line I2Is the radius of the circle on which the circular arc line II is located, theta2Is the central angle corresponding to the circular arc line II, L is the length of the weaving area of the cover plate cloth along the warp direction, D is the width of the weaving area of the cover plate cloth along the weft direction, and lambdaWeft yarnWeft density, lambda, of the area woven with the cloth for the cover plateWarp beamThe warp density of the cloth weaving area for the cover plate; w1The distance W between the 1 st weft yarn when weaving the fabric weaving area for the cover plate and the 1 st weft yarn when weaving the curve surface2The distance W between the 1 st warp yarn when weaving the fabric weaving area for the cover plate and the 1 st warp yarn when weaving the curved surface3The distance between the last 1 weft yarn when weaving the fabric weaving area for the cover plate and the 1 st weft yarn when weaving the curve surface, W4The last 1 warp yarn when weaving the fabric weaving area for the cover plate and the 1 st warp yarn when weaving the curved surfaceThe distance between the two parts, the angle unit is radian;
when the cover plate is woven by cloth, placing a grid-shaped support body with the same curved surface in the area from the corresponding cloth fell to the first row of heddles; the grid-shaped support body 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 dents of the reed, and the thickness of each thin plate is 1/3 smaller than the interval between every two adjacent dents of the reed;
when the cover plate is woven by cloth, each warp yarn is independently and passively let-off under constant tension;
(2) sequentially brushing a treating agent and a binder on the cloth for the cover plate, and drying;
(3) arranging the cover plate which is dried and preheated in the step (2) in a mold by adopting a mold injection molding method, performing injection molding by taking a mixture of a curing agent and epoxy resin as an injection molding raw material, and performing curing treatment;
(4) and (5) carrying out spraying treatment to manufacture the upper cover plate of the notebook computer.
6. The method for preparing an upper cover plate of a notebook computer with fabric according to claim 5, wherein when each stitch point is formed, a corresponding let-off amount is further set:
(1.1) when wi＜W1Or wi＞L-W3Or wj＜W2Or wj＞D-W4When s isij＝10/λWeft yarn；
(1.2) when W1≤wi≤W1+R1sinθ1And W is2≤wj≤W2+R2sinθ2When the temperature of the water is higher than the set temperature,
if it isThen sij＝10/λWeft yarn；
If it isThen
(1.3) when W1≤wi≤W1+R1sinθ1And D-W4-R2sinθ2≤wj≤D-W4When the temperature of the water is higher than the set temperature,
if it isThen sij＝10/λWeft yarn；
If it isThen
(1.4) when W1≤wi≤W1+R1sinθ1And W is2+R2sinθ2＜wj＜D-W4-R2sinθ2When the temperature of the water is higher than the set temperature,
(1.5) when W1+R1sinθ1＜wi≤L-W3When s isij＝10/λWeft yarn；
wi＝i×10/λWeft yarn；
vj＝j×10/λWarp beam；
Wherein s isijWhen weaving the fabric weaving area for the cover plate, the let-off amount of a weave point formed by the ith weft yarn and the jth warp yarn is i-1, the.. m, j-1, the.. n, wherein m is the number of beating-up times, and n is the number of warp yarns; r1Is the radius of the circle on which the circular arc line I is located, theta1Is the central angle, R, corresponding to the circular arc line I2Is the radius of the circle on which the circular arc line II is located, theta2Is the central angle corresponding to the circular arc line II, L is the length of the weaving area of the cover plate cloth along the warp direction, D is the width of the weaving area of the cover plate cloth along the weft direction, and lambdaWeft yarnWeft density, lambda, of the area woven with the cloth for the cover plateWarp beamThe warp density of the cloth weaving area for the cover plate; w1The distance W between the 1 st weft yarn when weaving the fabric weaving area for the cover plate and the 1 st weft yarn when weaving the curve surface2The distance W between the 1 st warp yarn when weaving the fabric weaving area for the cover plate and the 1 st warp yarn when weaving the curved surface3The distance between the last 1 weft yarn when weaving the fabric weaving area for the cover plate and the 1 st weft yarn when weaving the curve surface, W4The radian is used as the angle unit for the distance between the last 1 warp yarn when weaving the area of the cover plate fabric and the 1 st warp yarn when weaving the curve surface.
7. The method for preparing the upper cover plate of the notebook computer with the fabric, according to claim 5, wherein the treating agent in the step (2) is absolute ethyl alcohol, and the binder is a silane coupling agent KH 550; the content of the binder on the dried cloth for the cover plate is 1-2 wt%;
in the step (3), the surface temperature of the preheated cover plate cloth is more than 130 ℃; the curing agent is polyamide resin 651#, and the epoxy resin is hydantoin epoxy resin; the content of the curing agent on the cloth for the cover plate after curing treatment is 1-3 wt%.
8. The method for preparing an upper cover plate of a notebook computer comprising a fabric according to claim 5, wherein in the weaving method of the cloth for the cover plate, before weft insertion, after weft insertion or after beating-up is performed when each weave point is formed; the thin plate is made of metal;
the tension of the warp is 40-70 cN/piece; the tension of the weft yarns is 15-23 cN/root;
the winding speed is 20-20.7 cm/min, and the beating-up speed is 12-16 pieces/min.
9. The method for preparing an upper cover plate of a notebook computer with fabric according to claim 8, wherein the horizontal distance from the weave point to the heddle eyes of the first row of heddles is 2 to 5 times the height of the lifting heddle.
10. The method for preparing the upper cover plate of the notebook computer with the fabric, according to claim 8, wherein the passive let-off is realized by adopting a torsion spring type tension adjusting device.
Technical Field
The invention belongs to the technical field of notebook accessories, and relates to a fabric-containing upper cover plate of a notebook computer and a preparation method thereof.
Background
With the development of computer technology, notebook computers with light weight, strong functions and convenient carrying are more popular with users, and in order to meet the requirements of rigidity, portability, aesthetic property and the like of the whole notebook computer, the casing of the notebook computer is usually developed into a composite material molding form by high-strength plastic injection molding. The carbon fiber reinforced composite plastic is a novel composite material and is formed by compounding carbon fibers and matrix plastic. It has the features of high specific strength, high specific modulus, high elasticity, high fatigue resistance, high wear resistance, high vibration resistance, high heat conductivity, high heat resistance, etc.
In the case of the notebook computer, the carbon fiber woven cloth adopted in the prior art is a 2D fabric, and the shape of the notebook computer cover plate is irregular, the carbon fiber woven cloth is in a composite material, particularly in a folding/pleating form at corners, the folding/pleating structure is not only not in accordance with the flatness of the composite material of the computer cover plate to the surface and the aesthetic indexes of an outer pipe and the like, but also cannot be well connected, so that the joint of the folding/pleating structure is relatively loose and weak, and the bearing capacity of the composite material at the corners is reduced.
Disclosure of Invention
The invention aims to solve the problems that a computer cover plate is not attractive and the bearing capacity at corners is not enough in the prior art, and provides a notebook computer upper cover plate containing fabric and a preparation method thereof.
In order to achieve the purpose, the technical scheme adopted by the invention is as follows:
a notebook computer upper cover plate containing fabric mainly comprises cover plate cloth and thermosetting epoxy resin; the content of the thermosetting epoxy resin is 25-30 wt%;
the cover plate cloth is a single-layer plain woven fabric formed by interweaving warp yarns and weft yarns; the surface of the single-layer plain woven fabric includes a curved surface (one of curved surfaces); the generatrix of the curve surface consists of a line segment I and an arc line I formed by extending from two ends of the line segment I, and the symmetry axis of the generatrix is a perpendicular bisector of the line segment I; the lead of the curve surface consists of a line segment II and an arc line II formed by extending from one end of the line segment II; the orthographic projection surface of the curve surface on the horizontal plane is rectangular, the long side of the rectangle corresponds to the orthographic projection line of the bus, and the short side corresponds to the orthographic projection line of the lead; it should be noted that the shape referred to herein is a shape obtained by ignoring microscopic undulations of the woven fabric surface caused by the interweaving of warp and weft yarns;
all warps on the single-layer plain woven fabric are parallel to the plane of any bent warp; all weft yarns on the single-layer plain woven fabric are parallel to the plane where any one bent weft yarn is located; the warp density and the weft density of each part of the single-layer plain woven fabric are the same. The curved surface form of the single-layer plain woven fabric is the same as the surface shape of the upper cover plate.
As a preferred technical scheme:
according to the notebook computer upper cover plate containing the fabric, the diameter of the circle where the circular arc line I is located is the same as that of the circle where the circular arc line II is located;
warp density lambda of single layer plain woven fabricWarp beam5 to 7 pieces/10 cm, weft density lambdaWeft yarn5-7 roots/10 cm; the larger the fineness of the yarn, the corresponding warp densityThe smaller the weft density;
the warp yarns and the weft yarns are 20k of polyacrylonitrile-based carbon fibers, the modulus of the polyacrylonitrile-based carbon fibers is 230-240 GPa, and the strength is 3500-3600 MPa.
The cloth for the cover plate has the fitting coefficient of more than 98.9 percent.
The bending strength of the upper cover plate of the notebook computer containing the fabric is 280-350 MPa, and the impact strength reaches 62.3-74.2 KJ.m-2。
The performance of the upper cover plate of the notebook computer is measured by adopting the impact performance of the carbon fiber/epoxy resin composite material and using a memory type impact tester JJ-20, and the impact performance is tested according to the GB/T1843-1996 standard requirements.
The method for preparing the upper cover plate of the notebook computer containing the fabric comprises the following steps:
(1) weaving the cloth for the cover plate: adopting a plain weaving process, and arranging a fabric weaving area for the cover plate, wherein the fabric weaving area for the cover plate comprises a curved surface of the single-layer plain woven fabric and an extension surface of the curved surface extending towards the periphery of the single-layer plain woven fabric, and when each weave point is formed, setting the corresponding heddle eye height to prepare the fabric for the cover plate;
the corresponding calculation method of the height of the heddle eye comprises the following steps:
(1.1) when wi<W1Or wi>L-W3Or wj<W2Or wj>D-W4When h is presentij＝0；
(1.2) when W1≤wi≤W1+R1 sin θ1And W is2≤wj≤W2+R2 sin θ2When the temperature of the water is higher than the set temperature,
if it isThen h isij＝0；
If it isThen
(1.3) when W1≤wi≤W1+R1 sin θ1And D-W4-R2 sin θ2≤wj≤D-W4When the temperature of the water is higher than the set temperature,
if it isThen h isij＝0；
If it isThen
(1.4) when W1≤wi≤W1+R1 sin θ1And W is2+R2 sin θ2<wj<D-W4-R2 sin θ2When the temperature of the water is higher than the set temperature,
(1.5) when W1+R1 sin θ1<wi≤L-W3When the temperature of the water is higher than the set temperature,
and, if W2≤wj≤W2+R2 sin θ2Then, then
If D-W4-R2 sin θ2≤wj≤D-W4Then, then
If W2+R2 sin θ2<wj<D-W4-R2 sin θ2Then h isij＝R2(1-cos θ2)；
wi＝i×10/λWeft yarn；
vj＝j×10/λWarp beam；
Wherein h isijThe harness eye height (cm) of a weave point formed by the ith weft yarn and the jth warp yarn when weaving the cover plate cloth weaving area is 1, i is equal to 1, m, j is equal to 1, n is equal to n, m is the number of beating-up times, and n is the number of warp yarns; r1Is the radius (cm), theta, of the circle on which the circular arc line I is positioned1Is the central angle, R, corresponding to the circular arc line I2Is the radius (cm), theta, of the circle on which the circular arc line II is positioned2L is the length (cm) of the woven region of the cover sheet cloth along the warp direction (length equal to or greater than the length of both ends of the extended surface of the helmet reinforcing cloth along the warp direction), D is the width (cm) of the woven region of the cover sheet cloth along the weft direction (length equal to or greater than both ends of the extended surface of the helmet reinforcing cloth along the weft direction), and λWeft yarnWeft density, lambda, of the area woven with the cloth for the cover plateWarp beamWarp density (each defined as the number of yarns arranged in parallel perpendicular to the length direction within a length of 10cm) of a woven region of the cover sheet; w is aiAnd vjIntermediate transition parameters; w1The distance W between the 1 st weft yarn when weaving the fabric weaving area for the cover plate and the 1 st weft yarn when weaving the curve surface2The distance W between the 1 st warp yarn when weaving the fabric weaving area for the cover plate and the 1 st warp yarn when weaving the curved surface3The distance between the last 1 weft yarn when weaving the fabric weaving area for the cover plate and the 1 st weft yarn when weaving the curve surface, W4The radian is used as the radian for the angle unit, wherein the radian is used as the distance between the last 1 warp yarn when weaving the area of the cover plate by using the cloth and the 1 st warp yarn when weaving the curve surface;
when the cover plate is woven by the cloth, placing a grid-shaped support body with the same curved surface (namely the curved surface shape of the cover plate cloth) on the surface from a cloth fell corresponding to a weaving area of the cover plate cloth to a first row of harness wire area; the grid-shaped support body 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 dents of the reed, and the thickness of each thin plate is 1/3 smaller than the interval between every two adjacent dents of the reed; the number of the plurality of thin plates can be calculated according to the distance between the adjacent thin plates and the thickness of the thin plates and the width of the whole grid-shaped support body.
When the cover plate is woven by cloth, each warp yarn is independently and passively let-off under constant tension;
when the introduced weft yarns are punched into the weaving opening by the reed, the weft yarns are distributed along the upper surface of the supporting body one by one and can support the warp yarns to ensure the stability of the shape of the woven curved surface.
(2) Sequentially brushing a treating agent and a binder on the cloth for the cover plate, and drying (the drying temperature is 60 ℃);
(3) arranging the cover plate which is dried and preheated in the step (2) in a mold by adopting a mold injection molding method, performing injection molding by taking a mixture of a curing agent and liquid epoxy resin as an injection molding raw material, and performing curing treatment;
(4) and (5) carrying out spraying treatment to manufacture the upper cover plate of the notebook computer.
As a preferred technical scheme:
according to the preparation method of the upper cover plate of the notebook computer containing the fabric, the treating agent in the step (2) is absolute ethyl alcohol, and the binder is a silane coupling agent KH 550; the content of the binder on the dried cloth for the cover plate is 1-2 wt%;
in the step (3), the surface temperature of the preheated cover plate cloth is more than 130 ℃; the curing agent is polyamide resin 651#, and the epoxy resin is hydantoin (Hydantion) epoxy resin; the content of the curing agent on the cloth for the cover plate after curing treatment is 1-3 wt%.
In the above method for preparing the upper cover plate of the notebook computer including the fabric, when each stitch point is formed, the corresponding let-off amount is further set as follows:
(1.1) when wi<W1Or wi>L-W3Or wj<W2Or wj>D-W4When s isij＝10/λWeft yarn；
(1.2) when W1≤wi≤W1+R1 sin θ1And W is2≤wj≤W2+R2 sin θ2When the temperature of the water is higher than the set temperature,
if it isThen sij＝10/λWeft yarn；
If it isThen
(1.3) when W1≤wi≤W1+R1 sin θ1And D-W4-R2 sin θ2≤wj≤D-W4When the temperature of the water is higher than the set temperature,
if it isThen sij＝10/λWeft yarn；
If it isThen
(1.4) when W1≤wi≤W1+R1 sin θ1And W is2+R2 sin θ2<wj<D-W4-R2 sin θ2When the temperature of the water is higher than the set temperature,
(1.5) when W1+R1 sin θ1<wi≤L-W3When s isij＝10/λWeft yarn；
wi＝i×10/λWeft yarn；
vj＝j×10/λWarp beam；
Wherein s isijWhen weaving the fabric weaving area for the cover plate, the let-off amount of a weave point formed by the ith weft yarn and the jth warp yarn is i-1, the.. m, j-1, the.. n, wherein m is the number of beating-up times, and n is the number of warp yarns; r1Is the radius of the circle on which the circular arc line I is located, theta1Is the central angle, R, corresponding to the circular arc line I2Is the radius of the circle on which the circular arc line II is located, theta2Is the central angle corresponding to the circular arc line II, L is the length of the weaving area of the cover plate cloth along the warp direction, D is the width of the weaving area of the cover plate cloth along the weft direction, and lambdaWeft yarnWeft density, lambda, of the area woven with the cloth for the cover plateWarp beamThe warp density of the cloth weaving area for the cover plate; w1The distance W between the 1 st weft yarn when weaving the fabric weaving area for the cover plate and the 1 st weft yarn when weaving the curve surface2The distance W between the 1 st warp yarn when weaving the fabric weaving area for the cover plate and the 1 st warp yarn when weaving the curved surface3The distance between the last 1 weft yarn when weaving the fabric weaving area for the cover plate and the 1 st weft yarn when weaving the curve surface, W4The radian is used as the angle unit for the distance between the last 1 warp yarn when weaving the area of the cover plate fabric and the 1 st warp yarn when weaving the curve surface.
In the method for manufacturing the notebook computer upper cover plate containing the fabric, in the weaving method of the cloth for the cover plate, each tissue point is formed before weft insertion, after weft insertion or after beating up; the thin plate is made of metal;
the tension of the warp is 40-70 cN/piece; the tension of the weft yarns is 15-23 cN/root;
the winding speed is 20-20.7 cm/min, and the beating-up speed is 12-16 pieces/min; the warp beam is provided with a tension control and regulation system, and the tension of warp yarns can be ensured to be uniform by controlling the speed of the warp feeding line.
According to the preparation method of the notebook computer upper cover plate containing the fabric, when each weave point is formed, the horizontal distance from the weave point to the heddle eyes of the first row of heddles is set to be 2-5 times of the height of the lifting heddle; the height of the lifting heddle is the height of the heddle eyes of the first row of heddles compared with the horizontal plane of the weft yarn during weft insertion.
In the above method for preparing the upper cover plate of the notebook computer comprising the fabric, the passive let-off refers to the use of a torsion spring type tension adjusting device. The package of warp yarns is placed on a creel, and the yarn drawn from each bobbin is provided with a torsion spring type tension adjusting device, and the tension of each warp yarn in the let-off process is kept constant.
The height of the heddle eye of the heddle corresponding to each warp yarn is adjusted before each beating-up, and the heddle eyes are respectively and independently connected with different lifting mechanisms to control the lifting of the heddles to a certain height.
The mechanism of the invention is as follows:
in the prior art, compared with a two-dimensional fabric, the three-dimensional fabric does not need to be cut and sewn during composite forming, the integrity of the fabric is improved, the composite forming process is simplified, and the prepared three-dimensional fabric has great superiority in overall layering resistance, impact resistance and fatigue resistance compared with a two-dimensional woven fabric composite material.
Compared with the integrally formed three-dimensional fabric in the prior art, the plane of the weft yarn in the three-dimensional curved surface area is not parallel to each other on the integrally formed three-dimensional fabric in the prior art, and the fabric integrally presents uneven warp density and weft density in different areas, so that the uneven fabric structure can cause uneven stress on each area when the fabric is stressed; on the basis that all the warp yarns are parallel to the plane where the warp yarns of the three-dimensional curved surface area are located and all the weft yarns are parallel to the plane where the weft yarns of the three-dimensional curved surface area are located, the warp and weft densities in all the areas are uniform, and the uniform stress of the integrally-formed three-dimensional fabric is guaranteed.
In order to prepare the cover plate cloth (three-dimensional fabric) in the invention, the grid-shaped support body is adopted to weave the cover plate cloth, compared with a special-shaped roller reeling method, in the weaving process of the special-shaped roller reeling method, the linear speed at the small end area of the special-shaped roller is smaller than the linear speed at the large end area of the special-shaped roller, so that the density of weft yarns at the small end area of the special-shaped roller is greater than that at the large end area of the special-shaped roller, and the density of weft yarns of the three-dimensional fabric prepared by the special-shaped roller; 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 does not influence the interweaving of yarns, weft yarns can be arranged at equal intervals when in beating, the weft yarns are linear in the projection direction of a finished 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 of the cloth for the cover plate, the height of the heddle eyes and the let-off quantity are controlled according to the form of the curved surface area, and the let-off quantity increment 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, 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.
Meanwhile, the curved fabric prepared by the grid method has better fitting degree with the designed shape, the existence of the grid-shaped support body enables the fitting effect to be excellent and the variety to be changed more quickly without the need of carrying out optimization in the previous design and detection and correction of the fitting degree in the later period.
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.
In the weaving process of the three-dimensional fabric, the let-off of the three-dimensional fabric with small curvature is suitable for passive let-off, because the difference of the lifting height of each warp yarn of the three-dimensional fabric with small curvature is small during weaving, the warp yarn with high lifting height can not exceed the length adjusting space of a tension device (namely, the warp yarn is kept under constant tension) in a passive let-off system because of being excessively pulled out, the process is simple, and the application range is wide. The purpose of passive let-off is to ensure that let-off quantity and tension are controllable and accurate, so as to ensure that the density of the woven three-dimensional fabric is uniform, and the technical requirement on the fit coefficient is realized under the supporting action of the grid-shaped supporting body.
The invention adopts the single-layer cover plate cloth which is integrally formed, because the fit coefficient of the cover plate cloth is high, the consistency of the curved surface shape of the cover plate cloth and the curved surface shape of the manufactured computer upper cover plate can be ensured to the maximum extent when the composite material is formed, and because folding/pleating does not exist, the invention is quite in line with the current aesthetic concept.
Advantageous effects
(1) According to the preparation method of the upper cover plate of the notebook computer containing the fabric, warp and weft yarns can be interwoven on the curved surface by controlling the warp yarn let-off amount and the heald lifting stroke, and cover plate cloth with a specific curved surface form can be prepared;
(2) the upper cover plate of the notebook computer containing the fabric provided by the invention is quite in line with the current aesthetic concept, no structural defects exist at all positions of the upper cover plate of the computer, and the bearing capacity of the corners of the upper cover plate of the computer is stronger.
Drawings
Fig. 1 is a schematic diagram of a woven region of a fabric for a cover plate and an extended surface thereof, in which (a) is a schematic diagram of a top view of the woven region of the fabric for a cover plate and the extended surface thereof, (b) is a schematic diagram of a lead, and (c) is a schematic diagram of a bus bar.
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.
A preparation method of an upper cover plate of a notebook computer containing fabric comprises the following specific steps:
(1) firstly, preparing raw materials;
warp yarn: 20K of polyacrylonitrile-based carbon fiber, the modulus of 235GPa, the strength of 3500MPa and the elongation at break of 1.7 percent;
weft yarn: 20K of polyacrylonitrile-based carbon fiber, the modulus of 235GPa, the strength of 3500MPa and the elongation at break of 1.7 percent;
(2) adopting plain weaving process, setting a cloth weaving area for the cover plate, wherein the cloth weaving area for the cover plate comprises a curved surface of a single-layer plain woven fabric and an extension surface (a plane and the outline shape of the extension surface is rectangular) extending from the curved surface to the periphery of the single-layer plain woven fabric;
the corresponding heddle eye height and let-off quantity are set as follows:
as shown in fig. 1(a), a top view of a weaving area of the cover plate cloth is schematically illustrated, wherein the weaving area of the cover plate cloth has a length l (cm) and a width d (cm); the left lower corner point O of the cloth weaving area for the cover plate is used as an original point (virtual point), and the weft density and the warp density are respectively set as lambdaWeft yarn、λWarp beam(each is defined as the number of yarns arranged in parallel in the direction perpendicular to the longitudinal direction within 10cm in length), P represents a weave point where the i-th weft yarn and the j-th warp yarn (yarn numbers i and j are positive integers) intersect (for the sake of understanding described below, the shapes of the weft yarn i and the warp yarn j when P is on a curved plane are shown in FIGS. 1(b) and 1(c), respectively),
let wi＝i×10/λWeft yarnLet vj＝j×10/λWarp beamThen the lifting height h of point PijAnd let-off amount sijThe calculation method comprises the following steps:
(2.1) when wi<W1Or wi>L-W3Or wj<W2Or wj>D-W4When h is presentij＝0；sij＝10/λWeft yarn；
(2.2) when W1≤wi≤W1+R1 sin θ1And W is2≤wj≤W2+R2 sin θ2When the temperature of the water is higher than the set temperature,
if it isThen h isij＝0；sij＝10/λWeft yarn；
If it isThen
(2.3) when W1≤wi≤W1+R1 sin θ1And D-W4-R2 sin θ2≤wj≤D-W4When the temperature of the water is higher than the set temperature,
if it isThen h isij＝0；sij＝10/λWeft yarn；
If it isThen
(2.4) when W1≤wi≤W1+R1 sin θ1And W is2+R2 sin θ2<wj<D-W4-R2 sin θ2When the temperature of the water is higher than the set temperature,
(2.5) when W1+R1 sin θ1<wi≤L-W3When s isij＝10/λWeft yarn；
And, if W2≤wj≤W2+R2 sin θ2Then, then
If D-W4-R2 sin θ2≤wj≤D-W4Then, then
If W2+R2 sin θ2<wj<D-W4-R2 sin θ2Then h isij＝R2(1-cos θ2)；
Wherein h isijThe heddle eye height (cm), s of the weave point formed by the ith weft yarn and the jth warp yarn when weaving the fabric weaving area for the cover plateijWhen weaving the fabric weaving area for the cover plate, the let-off amount (cm) of a weave point formed by the ith weft yarn and the jth warp yarn is 1, i is equal to 1, and m is equal to 1, n is equal to n, m is the number of beating-up times, and n is the number of warp yarns; r1Is the radius (cm) of the circle where the circular arc line I is positioned (determined by the size design of the upper cover plate of the notebook computer), theta1The central angle (determined by the size design of the notebook upper cover plate) corresponding to the circular arc line I, R2Is the radius (cm) of the circle where the circular arc line II is positioned (determined by the size design of the upper cover plate of the notebook computer), theta2The central angle (determined by the size design of the notebook upper cover plate) corresponding to the circular arc line II, L is the length (cm) of the cloth weaving area for the cover plate along the warp direction, D is the width (cm) of the cloth weaving area for the cover plate along the weft direction, and lambdaWeft yarnThe weft density (6 pieces/10 cm), lambda, of the woven area of the cloth for the cover plateWarp beamThe warp density of the cloth weaving area for the cover plate (6 pieces/10 cm); w1The distance between the 1 st weft yarn when weaving the area of the cloth for the cover plate and the 1 st weft yarn when weaving the curve surface is 5cm, W2The distance between the 1 st warp yarn when weaving the area of the cloth for the cover plate and the 1 st warp yarn when weaving the curve surface is 5cm, W3The distance between the last 1 weft yarn when weaving the area of the cloth for the cover plate and the 1 st weft yarn when weaving the curve surface is 5cm, W4The distance between the last 1 warp yarn when weaving the area of the cover plate by using the cloth and the 1 st warp yarn when weaving the curve surface is 5cm, and the radian is used as an angle unit;
during weaving, placing grid-shaped support bodies with the surfaces presenting the same curved surface in the area from the corresponding cloth fell to the first row of heddles; the grid-shaped support body is formed by connecting a plurality of metal sheets which are arranged at equal intervals, the thickness direction of the sheets is the same as the weft yarn direction, the interval between every two adjacent sheets is the interval between every two adjacent dents of the reed, and the thickness of each sheet is 1/3 smaller than the interval between every two adjacent dents of the reed;
during weaving, a torsion spring type tension adjusting device is adopted to independently and passively send warp yarns under constant tension; the tension of the warp yarns is 45 cN/yarn; the tension of the weft yarn is 20 cN/root; the winding speed is 20.7cm/min, the beating-up speed is 13 pieces/min, the heddle eye height of the heddle corresponding to each warp yarn is adjusted before each beating-up, and the lifting of each heddle is controlled to a certain height by independently connecting different heddles with different lifting mechanisms; when each tissue point is formed, setting the horizontal distance from the tissue point to the heddle eyes of the first row of heddles to be 3 times of the height of the lifting heddle;
the prepared cloth for the cover plate is a single-layer plain woven fabric formed by interweaving warp yarns and weft yarns; the surface of the single-layer plain woven fabric is a curved surface; the generatrix of the curve surface consists of a line segment I and an arc line I formed by extending from two ends of the line segment I, and the symmetry axis of the generatrix is a perpendicular bisector of the line segment I; the lead of the curve surface consists of a line segment II and an arc line II formed by extending from one end of the line segment II; the diameter of the circle where the arc line I is located is the same as that of the circle where the arc line II is located; the orthographic projection surface of the curve surface on the horizontal plane is rectangular, the long side of the rectangle corresponds to the orthographic projection line of the bus, and the short side corresponds to the orthographic projection line of the lead; all warp yarns on the single-layer plain woven fabric are parallel to a plane where any warp yarn in a bent shape is located, all weft yarns are parallel to a plane where any weft yarn in a bent shape is located, and the warp density and the weft density of each position on the single-layer plain woven fabric are the same.
(3) Sequentially coating a treating agent (absolute ethyl alcohol) and a binder (a silane coupling agent KH550) on the cloth for the cover plate, and drying (the drying temperature is 60 ℃); the content of the binder on the dried cloth for the cover plate is 1 wt%;
(4) arranging the cover plate dried and preheated in the step (3) in a mold by adopting a mold injection molding method, performing injection molding by taking a mixture of a polyamide resin 651# curing agent and a liquid hydantoin (Hydantion) epoxy resin as an injection molding raw material, and performing curing treatment; wherein the surface temperature of the preheated cover plate cloth is 140 ℃; the content of polyamide resin 651# on the cover sheet cloth after the curing treatment was 2 wt%;
(5) and (5) carrying out spraying treatment to manufacture the upper cover plate of the notebook computer.
The bending strength of the prepared notebook computer upper cover plate containing the fabric is 315MPa, and the impact strength reaches 68.8 KJ.m-2(ii) a The content of the thermosetting epoxy resin was 28 wt%.
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