Design method of special-shaped 2.5 D capping rotary prefabricated body

Abstract

The invention discloses a design method of a special-shaped 2.5 D capped rotary prefabricated body, and belongs to the technical field of special-shaped 2.5 D capped rotary prefabricated bodies. The design method comprises the following steps: constructing a prefabricated body model; any vertical central section of the prefabricated body is defined as a datum plane, and the datum plane is divided into a plurality of areas in the forming direction of the prefabricated body; and calculating parameters of each area by adopting a unit cell method, wherein the parameters comprise the warp number, the warp layer number and the weft layer number. According to the method, the prefabricated body model is constructed, the vertical center section is defined as the datum plane, the multiple areas are divided, and the parameters of all the areas are accurately calculated through the unit cell method, so that the defects in the prior art are effectively overcome, and the design accuracy and the manufacturing reliability of the prefabricated body are improved.

Description

Technical Field

[0001] The invention relates to the technical field of special-shaped 2.5D capped revolving preforms, in particular to a design method for a special-shaped 2.5D capped revolving preform. Background Art

[0002] With the widespread application of composite materials in aerospace, automobile manufacturing, sports equipment and other fields, the demand for complex-shaped preforms is growing. In particular, special-shaped 2.5D capped revolving preforms play an important role in high-performance composite components due to their unique geometric shape and structural characteristics. However, the existing design methods of special-shaped 2.5D capped revolving preforms have several defects, which limit their further development in high-end application fields.

[0003] Existing design methods usually fail to effectively consider the fiber distribution and volume fraction changes in different regions of the preform when dealing with complex geometries. This neglect results in insufficient performance in key areas of the preform and is unable to meet the needs of high-performance applications.

[0004] Existing design methods often use a unified calculation formula when calculating the number of warp yarns, the number of warp layers, and the number of weft layers, failing to take into account the specific geometric characteristics and mechanical requirements of different regions, resulting in uneven stress distribution and insufficient structural strength of the preform in actual applications.

[0005] In view of the above problems, the present invention provides a new design method for a special-shaped 2.5D capped revolving preform, which effectively solves the defects in the prior art and improves the accuracy of preform design and the reliability of manufacturing by constructing a preform model, defining the vertical center section as the reference plane and dividing it into multiple regions, and using the unit cell method to accurately calculate the parameters of each region. Summary of the invention

[0006] The purpose of this section is to summarize some aspects of embodiments of the present invention and briefly introduce some preferred embodiments. Some simplifications or omissions may be made in this section and the specification abstract and the invention title of this application to avoid blurring the purpose of this section, the specification abstract and the invention title, and such simplifications or omissions cannot be used to limit the scope of the present invention.

[0007] In view of the above problems and / or the problems existing in the prior art, the present invention is proposed.

[0008] Therefore, the first object of the present invention is to provide a design method for a special-shaped 2.5D capped revolving preform, which can accurately calculate the parameters of each area using the unit cell method.

[0009] To solve the above technical problems, the present invention provides the following technical solutions: a design method for a special-shaped 2.5D capped reversible preform, which includes constructing a preform model; defining any vertical central section of the preform as a reference plane, and dividing the reference plane into multiple regions along the forming direction of the preform; and using a single cell method to calculate the parameters of each region, the parameters including the number of warp yarns, the number of warp layers, and the number of weft layers.

[0010] As a preferred solution of the design method of the special-shaped 2.5D capped rotary preform of the present invention, the number of warp yarns corresponding to the j-th warp layer and the i-th weft layer of the preform is expressed as:

[0011]

[0012] Among them, r ij It is expressed as the distance between the warp yarns of the jth warp layer and the ith weft layer and the central axis of the preform, P j It is a secret sutra;

[0013] The number of warp layers corresponding to the i-th weft layer of the preform is expressed as:

[0014]

[0015] Among them, L i is the thickness of the i-th latitude layer, and h is the unit cell thickness;

[0016] The number of weft layers corresponding to the jth warp layer of the preform is expressed as:

[0017]

[0018] Among them, L j is the length of the jth warp layer, P w It is the weft density.

[0019] As a preferred scheme of the design method of the special-shaped 2.5D capped revolving preform of the present invention, the reference plane is divided into a first area, a second area, a third area and a fourth area connected in sequence along the forming direction of the preform; and a coordinate system is established with the second center point on the central axis of the preform as the origin.

[0020] As a preferred scheme of the design method of the special-shaped 2.5D capped reversible preform of the present invention, wherein: the boundary points of the first area are defined as the first boundary point, the second boundary point and the third boundary point, the line between the first boundary point and the third boundary point is the outer arc, and the line between the second boundary point and the third boundary point is the inner arc; the length of the outer arc is greater than the length of the inner arc, the number of warp layers at the beginning of weaving is greater than the number of warp layers at the end; the number of weft layers on the outside is less than the number of weft layers on the inside, and the number of weft layers decreases from the inside to the outside of the first area.

[0021] As a preferred solution of the design method of the special-shaped 2.5D capped rotary preform of the present invention, the arc center of the outer arc is defined as the first center point, the arc center of the inner arc is defined as the second center point, the arc center of the jth warp layer is defined as the jth center point, the first center point is located on the central axis of the preform, the jth center point is located between the first center point and the second center point, and the radius of the jth warp layer is expressed as:

[0022]

[0023] Among them, Laeyr_NA 1 is the number of warp yarn layers between the first boundary point and the second boundary point;

[0024] The outer arc or inner arc can accommodate n weft layers, and calculate the coordinates of the n equally divided points of the outer arc and the inner arc, the number of warp layers contained in the i-th weft layer, and the number of warp yarns in the i-th weft of the j-th warp layer

[0025] As a preferred scheme for the design method of the special-shaped 2.5D capped reversible preform of the present invention, wherein: the boundary points of the second area are defined as the second boundary point, the fourth boundary point, the fifth boundary point and the third boundary point; the number of warp layers at the beginning and the end of weaving in the second area is the same; the number of weft layers on the outside of the second area is greater than the number of weft layers on the inside, and the number of weft layers gradually decreases from the outside to the inside of the second area.

[0026] As a preferred solution of the design method of the special-shaped 2.5D capped rotary preform of the present invention, the distance l between the jth warp layer and the second center point is calculated. j ;

[0027] Calculate the number of latitude layers contained in the jth longitude layer, expressed as:

[0028]

[0029] Calculate the number of warp yarns in the jth warp layer and the ith weft layer, expressed as:

[0030]

[0031] Wherein, M_x is the distance from the second boundary point or the fourth boundary point to the central axis of the preform.

[0032] As a preferred scheme of the design method of the special-shaped 2.5D capped reversible preform of the present invention, wherein: the boundary points of the third area are defined as the third boundary point, the fifth boundary point, the sixth boundary point and the seventh boundary point and the coordinates are read respectively; the number of weft yarn layers m between the third boundary point and the seventh boundary point is calculated by the coordinates, m≥0, the acute angle between the line connecting the third boundary point and the seventh boundary point and the central axis of the preform, the coordinates of the m equally divided points between the third boundary point and the sixth boundary point, the coordinates of the m equally divided points between the fifth boundary point and the sixth boundary point, the number of warp yarn layers in each weft, the difference between the number of warp yarn layers of two adjacent wefts and the number of warp yarns in the jth warp layer in each weft.

[0033] As a preferred solution of the design method of the special-shaped 2.5D capped rotary preform of the present invention, wherein: the boundary points of the fourth area are defined as the sixth boundary point, the seventh boundary point, the eighth boundary point and the ninth boundary point; the coordinates of the sixth boundary point are read, and the acute angles between the line connecting the sixth boundary point and the seventh boundary point and the line connecting the sixth boundary point and the ninth boundary point and the x-axis of the coordinate system are respectively obtained, which are expressed as α and β respectively;

[0034] Calculate the coordinates of the point in the jth longitude layer and the ith latitude layer (P ij _x,P ij _y), expressed as:

[0035]

[0036] Then calculate the number of warp yarns in the jth warp layer and the ith weft layer in the fourth area

[0037] The second object of the present invention is to provide a special-shaped 2.5D capped revolving preform, which is made by the above-mentioned design method of the special-shaped 2.5D capped revolving preform.

[0038] The beneficial effects of the present invention are as follows: by constructing a prefabricated body model, defining a vertical central section as a reference plane and dividing it into a plurality of regions, and using a unit cell method to accurately calculate the parameters of each region, the defects in the prior art are effectively solved, and the accuracy of prefabricated body design and the reliability of manufacturing are improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following briefly introduces the drawings required for describing the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative labor. Among them:

[0040] Figure 1 This is a cross-sectional view of a special-shaped 2.5D capped rotary preform.

[0041] Figure 2 This is the first area diagram of the design method of the special-shaped 2.5D capped rotary preform.

[0042] Figure 3 This is the second area diagram of the design method of the special-shaped 2.5D capped rotary preform.

[0043] Figure 4 This is the warp and weft diagram of the second area of ​​the design method for a special-shaped 2.5D capped rotary preform.

[0044] Figure 5 This is the third area diagram of the design method of the special-shaped 2.5D capped rotary preform.

[0045] Figure 6 This is the fourth area diagram of the design method of the special-shaped 2.5D capped rotary preform. DETAILED DESCRIPTION

[0046] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the specific implementation methods of the present invention are described in detail below in conjunction with the accompanying drawings.

[0047] In the following description, many specific details are set forth to facilitate a full understanding of the present invention, but the present invention may also be implemented in other ways different from those described herein, and those skilled in the art may make similar generalizations without violating the connotation of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed below.

[0048] Secondly, the present invention is described in detail with reference to schematic diagrams. When describing the embodiments of the present invention in detail, for the sake of convenience, the cross-sectional diagrams showing the device structure will not be partially enlarged according to the general scale, and the schematic diagrams are only examples, which should not limit the scope of protection of the present invention. In addition, in actual production, the three-dimensional dimensions of length, width and depth should be included.

[0049] Furthermore, the term "one embodiment" or "embodiment" as used herein refers to a specific feature, structure, or characteristic that may be included in at least one implementation of the present invention. The term "in one embodiment" that appears in different places in this specification does not necessarily refer to the same embodiment, nor does it refer to a separate or selective embodiment that is mutually exclusive with other embodiments.

[0050] Example 1

[0051] See also Figure 1 , which is the first embodiment of the present invention, and provides a design method for a special-shaped 2.5D capped rotary preform.

[0052] S100: Build prefabricated model;

[0053] S200: defining any vertical central cross section of the preform as a reference plane, and dividing the reference plane into a plurality of regions along a forming direction of the preform;

[0054] S300: Calculate the parameters of each area using the unit cell method, the parameters including the number of warp yarns, the number of warp layers, and the number of weft layers;

[0055] S301: Divide the reference plane into a first area, a second area, a third area and a fourth area connected in sequence along the molding direction of the preform; take the second center point (O 2 ) is used as the origin to establish a coordinate system.

[0056] Example 2

[0057] This is the third embodiment of the present invention, which is based on the first embodiment.

[0058] The number of warp yarns corresponding to the j-th warp layer and the i-th weft layer of the preform is expressed as:

[0059]

[0060] Among them, r ij It is expressed as the distance between the warp yarns of the jth warp layer and the ith weft layer and the central axis of the preform, P j For example, the coordinates of the 10th warp layer and the 10th weft layer are (30, 50) (in mm), P j is 8 / cm, find

[0061] The calculation process is as follows: The radius r of the position from the central axis 10,10 The horizontal coordinate of the point is 30, so the number of warp yarns in one circle at this position is:

[0062]

[0063] Therefore, the theoretical number of warp yarns at this position is 150.72. In actual weaving, the warp yarns are arranged in an even number. Therefore, considering factors such as volume fraction, the rounding method is chosen to approximate. Finally, the actual number of warp yarns contained in one circle at the 10th warp layer and the 10th weft layer is 152.

[0064] Example 3

[0065] This is the third embodiment of the present invention, which is based on the first embodiment.

[0066] The number of warp layers corresponding to the i-th weft layer of the preform is expressed as:

[0067] Layer i =L i / h

[0068] Among them, L i is the thickness of the i-th latitude layer, and h is the unit cell thickness;

[0069] For example, the preform thickness at the 10th latitude layer is 30 (in mm), and the unit cell thickness h is 0.915 mm. 10 .

[0070] The calculation process is as follows: The number of preform warp layers at the 10th weft layer is:

[0071] Layer 10 =3 / 0.0915=32.8

[0072] Therefore, the theoretical number of warp layers corresponding to the 10th latitude layer is 32.8 layers. The further approximation method is selected, and finally the number of warp layers corresponding to the 10th latitude layer is 33 layers.

[0073] Example 4

[0074] This is the third embodiment of the present invention, which is based on the first embodiment.

[0075] The number of weft layers corresponding to the jth warp layer of the preform is expressed as:

[0076]

[0077] Among them, L j is the length of the jth warp layer, P w It is the weft density;

[0078] Known: The length of the preform busbar of the 10th warp layer is 200 (in mm), the weft density P w is 4 / cm, find

[0079] The calculation process is as follows:

[0080] Example 5

[0081] See also Figure 2 , which is the third embodiment of the present invention, and this embodiment is based on embodiment 1.

[0082] Define the boundary points of the first area as the first boundary point N and the second boundary point A 1 and the third boundary point B 2 , the first boundary point N and the third boundary point B 2 The line between them is the outer arc, and the second boundary point A 1 and the third boundary point B 2 The line between them is the inner arc;

[0083] The length of the outer arc is greater than that of the inner arc, and the number of warp layers at the beginning of weaving is greater than that at the end;

[0084] The number of weft layers on the outer side is less than that on the inner side, and the number of weft layers decreases from the inner side to the outer side of the first region.

[0085] Define the center of the outer arc as the first center point O 1 , the center of the inner arc is the second center point O 2 , the arc center of the jth meridian layer is the jth circle center point O j , the first center point O 1 Located on the central axis of the preform, the jth circle center point O j Located at the center of the first circle O 1 and the second center point O 2 The radius of the jth warp layer is expressed as:

[0086]

[0087] Among them, Layer_NA 1 is the first boundary point N and the second boundary point A 1 The number of warp layers between;

[0088] The outer arc or inner arc can accommodate n weft layers, and calculate the coordinates of the n equally divided points of the outer arc and the inner arc, the number of warp layers contained in the i-th weft layer, and the number of warp yarns in the i-th weft of the j-th warp layer

[0089] Such as: AO 1 , O 1 O 2 The lengths are 2.5 and 8.855 cm respectively, NA 1 The number of warp yarn layers is 18, arc NB 2 The corresponding radius is 2.5cm, the central angle is 1.27, and arc A 1 B 2 The corresponding radius is 9.67cm, the central angle is 0.23, the preform unit cell thickness h is 0.0915cm, and the warp density P j 8 yarns / cm, weft density P w 4 yarns / cm. Find the number of warp yarns contained in one circle at the 2nd weft and 4th warp layer.

[0090] The calculation process is as follows: The radius calculation formula of the jth warp layer is:

[0091]

[0092] NB 2 The length of the arc segment is: 2.5×1.27=3.175cm, which can be divided into 7 latitudes; A 1 B 2The length of the segment arc is: 9.67×0.23=2.22cm, which can be divided into 5 latitudes;

[0093] Calculate NB 2 and A 1 B 2 The coordinates of the points where the segment is divided into seven equal parts:

[0094] NP_NB 2 _i+1_x=2.5*sin(0.1+i / 7+1.27)

[0095] NP_NB 2 _i+1_y=8.855+2.5*cos(0.1+i / 7+1.27

[0096] NP_A 1 B 2 _i+1_x=9.67*sin(0.025+i / 7+0.23)

[0097] NP_A 1 B 2 _i+1_y=9.67*cos(0.025+i / 7+0.23)

[0098] Among them, i starts from 0;

[0099] Calculate the number of warp layers contained in the i-th latitude:

[0100]

[0101] Calculate the warp yarn of the i-th weft and j-th warp layer

[0102]

[0103] For example, the number of warp yarns in one circle at the 4th warp layer of the 2nd weft is:

[0104]

[0105] Calculation completed.

[0106] Example 6

[0107] See also Figure 3 and Figure 4 , which is the fourth embodiment of the present invention, and this embodiment is based on embodiment 1 or embodiment 2.

[0108] Define the boundary point of the second region as the second boundary point A 1 , the fourth boundary point M, the fifth boundary point B 1 and the third boundary point B 2 ;

[0109] The number of warp layers at the beginning and end of weaving in the second area is the same;

[0110] The number of weft layers on the outer side of the second region is greater than that on the inner side, and the number of weft layers gradually decreases from the outer side to the inner side of the second region.

[0111] Calculate the jth warp layer and the second circle center point O 2 The distance between j ;

[0112] Calculate the number of latitude layers contained in the jth longitude layer, expressed as:

[0113]

[0114] Calculate the number of warp yarns in the jth warp layer and the ith weft layer, expressed as:

[0115]

[0116] Among them, M_x is the second boundary point A 1 Or the distance from the fourth boundary point M to the central axis of the preform.

[0117] For example: The second boundary point A 1 and the fourth boundary point M relative to the second center point O 2 The coordinates of (0,0) are (0.25,9.66) and (0.25,2.755) (in cm), A 1 O 2 B 2 The arc angle is 0.230. The preform unit cell thickness h is 0.0915cm, and the P j 8 threads / cm, weft density P w is 4 / cm. Find the distance from the jth meridian layer in this area to the second center point O 2 The distance L j , the number of weft layers that the j-th warp layer can accommodate and the number of warp yarns at any position, and calculate the number of warp yarns contained in a circle at the 2nd weft position of the 80th warp layer.

[0118] The calculation process is as follows:

[0119] L j =2.755+0.0915*(j-1)

[0120] Wherein, j is less than or equal to 75;

[0121] Calculate the number of latitude layers contained in the jth longitude layer:

[0122]

[0123] Calculate the number of warp threads at any position:

[0124]

[0125] Calculate the number of warp yarns contained in one circle at the 2nd weft position of the 80th warp layer:

[0126]

[0127] Calculation completed.

[0128] Example 7

[0129] See also Figure 5 , which is the fourth embodiment of the present invention, and this embodiment is based on embodiment 1 or embodiment 2.

[0130] Define the boundary point of the third region as the third boundary point B 2 、The fifth boundary point B 1 , the sixth boundary point C 1 and the seventh boundary point C 2 And read the coordinates respectively;

[0131] Calculate the third boundary point B by coordinates 2 and the seventh boundary point C 2 The number of weft yarn layers between 5, the third boundary point B 2 and the seventh boundary point C 2 The acute angle between the line connecting the three points and the central axis of the preform, the third boundary point B 2 and the sixth boundary point C 1 The coordinates of the 5 equally divided points between the fifth boundary point B 1 and the sixth boundary point C 1 The coordinates of the five equally divided points between the two wefts, the number of warp yarn layers in each weft, the difference in the number of warp yarn layers between two adjacent wefts, and the number of warp yarns in the jth warp layer in each weft.

[0132] For example: the third boundary point B 2 、The fifth boundary point B 1 , the sixth boundary point C 1 and the seventh boundary point C 2 Relative to the second center point O 2 The coordinates are (2.45,9.35), (0.721,2.755), (3.661,0.351), (4.249,0.470), and the fifth boundary point B 1 and the sixth boundary point C 1 The third center point O of the arc between 3 The coordinates are (0.721, -0.245), angle B 1 O 3 C 1 is 1.371, the warp and weft densities are 8 and 4 respectively, and the unit cell thickness is 0.0915cm. Find the number of warp yarns at any position. And the number of warp yarns contained in one circle at the 5th layer position of the 6th weft.

[0133] The calculation process is as follows:

[0134] Calculate B 2 C 2 Weft yarn layers:

[0135]

[0136] B 2 C 2 The acute angle with the y-axis is:

[0137]

[0138] The coordinates of the 19 equally divided points of B2C2 are:

[0139] B 2 C 2_ i+1_x=2.45+isin0.2

[0140] B 2 C 2_ i+1_y=2.45+icos0.2

[0141] Where i ranges from 0 to 19;

[0142] The coordinates of the 19 equally divided points of B1C1 are:

[0143]

[0144] Calculate the number of warp yarn layers per weft:

[0145]

[0146] Calculate the difference between the number of layers of two adjacent weft warp yarns:

[0147]

[0148] It is used to calculate part of the weft insertion basis;

[0149] Calculate the number of warp yarns in the jth layer for each weft. When i is an odd number, partial weft insertion is used, and the number of weft insertion layers is The calculation formula for the radius of the warp yarn in the i-th weft layer is:

[0150] r_ij=B 2 C 2 _i_x-0.0915*(j-1)sin(β_i)

[0151] The only unknown in this formula is:

[0152]

[0153] When i is an even number, all weft insertions are used for weaving, and the calculation formula for the radius of the i-th weft and j-th warp yarn is:

[0154] r_ij=B 2 C 2 _i_x-0.0915*(j-1)sin(β_i-1)

[0155] so

[0156]

[0157] The calculation formula for the number of warp yarns in the 5th layer of the 6th weft is:

[0158]

[0159] Calculation completed.

[0160] Example 8

[0161] See also Figure 6 , which is the fourth embodiment of the present invention, and this embodiment is based on embodiment 1 or embodiment 2.

[0162] Define the boundary point of the fourth region as the sixth boundary point C 1 , the seventh boundary point C 2 、The eighth boundary point C 4 and the ninth boundary point C 3 ;

[0163] Read the sixth boundary point C 1 The coordinates of the sixth boundary point C are obtained respectively. 1 and the seventh boundary point C 2 The line connecting the sixth boundary point C 1 and the ninth boundary point C 3 The acute angles between the line connecting and the x-axis of the coordinate system are denoted as α and β respectively;

[0164] Calculate the coordinates of the point in the jth longitude layer and the ith latitude layer (P ij _x,P ij _y), expressed as:

[0165]

[0166] Then calculate the number of warp yarns in the jth warp layer and the ith weft layer in the fourth area

[0167] For example: the sixth boundary point C 1 Relative to the second center point O 2 The coordinates are (3.66, 0.35) (in cm), C 1C 2 The angle α with the x-axis is 0.1998, C 1 C 3 The angle β with the x-axis is 1.371, all in radians. The preform unit cell thickness h is 0.0915 cm, and the P j 8 yarns / cm, weft density P w is 4 / cm. Find the coordinates of the points on the jth warp layer and the ith weft layer in the fourth region (P ij _x,P ij _y) and the number of warp yarns at any position And find the coordinates and number of warp yarns at the 8th layer position of the 3rd weft.

[0168] The calculation process is as follows:

[0169] C 1 C 3 The length is 17.34cm, C 2 C 4 Length is 17.46cm, C 1 * 2 Length: 0.6 cm;

[0170] Calculate the warp layer:

[0171] 0.6 / 0.0915≈7 layers

[0172] Calculate the latitude layer:

[0173] 17.46 / 2*4≈35 floors

[0174] The coordinates of the points in the jth longitude layer and the ith latitude layer are:

[0175] P ij _x=3.66+0.0915(j-1)cos0.1998+(i-1)cos1.371

[0176] P ij _y=0.35+0.0915(j-1)sin0.1998-(i-1)sin1.371

[0177] Where i is less than or equal to 35, j is less than or equal to 7, both are positive integers;

[0178] The number of warp yarns contained in one circle at the jth warp layer and the ith weft layer:

[0179]

[0180] The coordinates of the 8th layer at the 3rd latitude are:

[0181] P ij_x=3.66+0.0915(8-1)cos0.1998+(3-1)cos1.371

[0182] P ij _y=0.35+0.0915(8-1)sin0.1998-(3-1)sin1.371

[0183] Number of warp yarns in the 8th layer of the 3rd weft position:

[0184]

[0185] Calculation completed.

[0186] Based on the above, the beneficial effects of the present invention are:

[0187] First, the reference surface is divided into multiple specific areas along the forming direction of the preform. The shapes of the specific areas are easy to calculate, such as arcs, sectors and rectangles. Then, targeted calculation methods are used to calculate the parameters of each area for the areas with specific shapes, so as to obtain the weaving parameters.

[0188] Importantly, it should be noted that the construction and arrangement of the present application shown in a plurality of different exemplary embodiments are only exemplary. Although only a few embodiments are described in detail in this disclosure, it should be readily understood by those who refer to this disclosure that many modifications are possible (e.g., the size, scale, structure, shape and proportion of various elements, and parameter values ​​(e.g., temperature, pressure, etc.), installation arrangement, use of materials, color, directional changes, etc.) without substantially departing from the novel teachings and advantages of the subject matter described in the application. For example, the element shown as integrally formed can be composed of multiple parts or elements, the position of the element can be inverted or otherwise changed, and the nature or number or position of the discrete element can be changed or changed. Therefore, all such modifications are intended to be included in the scope of the present invention. The order or sequence of any process or method steps can be changed or reordered according to alternative embodiments. In the claims, any "device plus function" clause is intended to cover the structure of performing the function described herein, and is not only structurally equivalent but also equivalent structure. Without departing from the scope of the present invention, other replacements, modifications, changes and omissions can be made in the design, operating conditions and arrangement of the exemplary embodiments. Therefore, the invention is not limited to a specific embodiment, but extends to numerous modifications still falling within the scope of the appended claims.

[0189] Additionally, in order to provide a concise description of exemplary embodiments, all features of an actual embodiment (ie, those features that are not relevant to the best mode presently contemplated for carrying out the invention or those that are not relevant to implementing the invention) may not be described.

[0190] It will be appreciated that in the development of any actual implementation, as in any engineering or design project, numerous implementation-specific decisions may be made. Such a development effort may be complex and time-consuming, but will be a routine task of design, fabrication, and production for those of ordinary skill having the benefit of this disclosure without undue experimentation.

[0191] It should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solutions of the present invention may be modified or replaced by equivalents without departing from the spirit and scope of the technical solutions of the present invention, which should all be included in the scope of the claims of the present invention.

Claims

1. A design method for a special-shaped 2.5D capped rotary preform, characterized in that: include: Build prefab models; Define any vertical center section of the preform as a reference plane, and divide the reference plane into multiple regions along the forming direction of the preform; The unit cell method is used to calculate the parameters of each area, including the number of warp yarns, the number of warp layers, and the number of weft layers.

2. The design method of the special-shaped 2.5D capped rotary preform according to claim 1, characterized in that: The number of warp yarns corresponding to the j-th warp layer and the i-th weft layer of the preform is expressed as: Among them, ri j It is expressed as the distance between the warp yarns of the jth warp layer and the ith weft layer and the central axis of the preform, P j It is a secret sutra; The number of warp layers corresponding to the i-th weft layer of the preform is expressed as: Layer i =L i / h Among them, L i is the thickness of the i-th latitude layer, and h is the unit cell thickness; The number of weft layers corresponding to the jth warp layer of the preform is expressed as: Among them, L j is the length of the jth warp layer, P w It is the weft density.

3. The design method of the special-shaped 2.5D capped rotary preform according to claim 2, characterized in that: The reference plane is divided into a first region, a second region, a third region and a fourth region which are connected in sequence along the molding direction of the preform; and a coordinate system is established with a second center point (O2) on the central axis of the preform as the origin.

4. The design method of the special-shaped 2.5D capped rotary preform according to claim 3, characterized in that: The boundary points of the first region are defined as a first boundary point (N), a second boundary point (A1) and a third boundary point (B2), a line between the first boundary point (N) and the third boundary point (B2) is an outer arc, and a line between the second boundary point (A1) and the third boundary point (B2) is an inner arc; The length of the outer arc is greater than that of the inner arc, and the number of warp layers at the beginning of weaving is greater than that at the end; The number of weft layers on the outer side is less than that on the inner side, and the number of weft layers decreases from the inner side to the outer side of the first region.

5. The design method of the special-shaped 2.5D capped rotary preform according to claim 4, characterized in that: Define the center of the outer arc as the first center point (O1), the center of the inner arc as the second center point (O2), and the center of the jth meridian layer as the jth center point (O j ), the first center point (O1) is located on the central axis of the preform, and the jth center point (O j ) is located between the first center point (O1) and the second center point (O2), and the radius of the jth warp layer is expressed as: Wherein, Layer_NA1 is the number of warp yarn layers between the first boundary point (N) and the second boundary point (A1); The outer arc or inner arc can accommodate n weft layers, and calculate the coordinates of the n equally divided points of the outer arc and the inner arc, the number of warp layers contained in the i-th weft layer, and the number of warp yarns in the i-th weft of the j-th warp layer 6. The design method of the special-shaped 2.5D capped rotary preform according to claim 3, characterized in that: The boundary points of the second region are defined as the second boundary point (A1), the fourth boundary point (M), the fifth boundary point (B1) and the third boundary point (B2); The number of warp layers at the beginning and end of weaving in the second area is the same; The number of weft layers on the outer side of the second region is greater than that on the inner side, and the number of weft layers gradually decreases from the outer side to the inner side of the second region.

7. The design method of the special-shaped 2.5D capped rotary preform according to claim 6, characterized in that: Calculate the distance l between the jth meridian layer and the second center point (O2) j ; Calculate the number of latitude layers contained in the jth longitude layer, expressed as: Calculate the number of warp yarns in the jth warp layer and the ith weft layer, expressed as: Wherein, M_x is the distance from the second boundary point (A1) or the fourth boundary point (M) to the central axis of the preform.

8. The design method of the special-shaped 2.5D capped rotary preform according to claim 3, characterized in that: defining the boundary points of the third region as a third boundary point (B2), a fifth boundary point (B1), a sixth boundary point (C1) and a seventh boundary point (C2) and reading the coordinates thereof respectively; The number of weft yarn layers m between the third boundary point (B2) and the seventh boundary point (C2) is calculated by coordinates, m ≥ 0, the acute angle between the line connecting the third boundary point (B2) and the seventh boundary point (C2) and the central axis of the preform, the coordinates of the m equally divided points between the third boundary point (B2) and the sixth boundary point (C1), the coordinates of the m equally divided points between the fifth boundary point (B1) and the sixth boundary point (C1), the number of warp yarn layers in each weft, the difference between the number of warp yarn layers of two adjacent wefts, and the number of warp yarns in the jth warp layer in each weft.

9. The design method of the special-shaped 2.5D capped rotary preform according to claim 3, characterized in that: The boundary points of the fourth region are defined as a sixth boundary point (C1), a seventh boundary point (C2), an eighth boundary point (C4) and a ninth boundary point (C3); Read the coordinates of the sixth boundary point (C1), and respectively obtain the acute angles between the line connecting the sixth boundary point (C1) and the seventh boundary point (C2), and the line connecting the sixth boundary point (C1) and the ninth boundary point (C3) and the x-axis of the coordinate system, which are expressed as α and β respectively; Calculate the coordinates of the point in the jth longitude layer and the ith latitude layer (P ij _x,P ij _y), expressed as: Then calculate the number of warp yarns in the jth warp layer and the ith weft layer in the fourth area 10. A special-shaped 2.5D capped rotary preform, characterized in that: The preform is made by the design method of the special-shaped 2.5D capped rotary preform as described in any one of claims 1 to 9.

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