Forming processing method for stringer-shaped composite material

Abstract

According to the forming processing method for the stringer-shaped composite material, the mode of multiple times of material spreading and multiple times of rolling forming is adopted, the phenomenon that fibers are twisted and wrinkled at the bent position due to the fact that a prepreg sheet is too thick during single-time rolling can be avoided, the forming processing quality of the composite material is guaranteed, and the strength of a final stringer finished product is guaranteed; the spreading device, the roller mechanism and the roller swing arm adopted in the forming machining process are all simple in structure, easy to operate and low in cost, the size of the stringer is not limited, the forming device can be suitable for forming stringer components of various sizes or particularly complex shapes, the application range is wide, and universality is achieved.

Description

Technical Field

[0001] The present invention relates to the technical field of resin matrix composites, and particularly to a forming and processing method for stringer-shaped composites. Background Art

[0002] As a key load-bearing component of lightweight structures in the fields of aerospace, rail transit, etc., the forming and processing technology of resin matrix composite stringers directly affects the mechanical properties, dimensional accuracy and manufacturing cost of components.

[0003] At present, the forming and processing of resin matrix composite stringers on the market mainly adopts manual hand laying or a tape laying machine to first lay prepregs layer by layer until the total thickness of the prepreg sheet formed by laying meets the required thickness of the stringer. Then, the prepreg sheet is placed on a hot diaphragm forming tool by using a forming technology such as a hot diaphragm, and the resin in the prepreg is softened and flowed by means of vacuum pumping and heating to fill into all corners of the mold, so as to achieve an ideal shape; finally, after reaching the predetermined time and temperature, it is completely cooled and cured.

[0004] However, due to the prepreg sheet having a certain thickness, when forming an Ω-shaped stringer, it needs to undergo bending deformations in different directions, and it is extremely easy to occur fiber bridging during the forming process, which will cause fiber twisting and wrinkling at the bending part of the sheet, affecting the stability of the product forming quality, and ultimately resulting in poor strength of the stringer. In addition, the hot diaphragm method is not applicable to the forming of large-sized or particularly complex-shaped stringer components, and does not have universality; moreover, the special equipment required by the hot diaphragm method has a large investment, and requires special operation skills, which limits its popularization and application. Summary of the Invention

[0005] The purpose of the present invention is to overcome the defects of the prior art, and provides a forming and processing method for stringer-shaped composites, which can solve the problems of unstable forming quality and limited application range existing in the existing forming and processing technology of stringer-shaped composites.

[0006] To achieve the above purpose and other purposes, the present invention is realized by including the following technical solutions: As a first aspect, the present invention proposes a forming and processing method for stringer-shaped composites, including:

[0007] Step 1: Cut the prepreg to a fixed width according to the shape of the mold and the finished stringer, and roll it into a prepreg coil;

[0008] Step 2: Install a plurality of the prepreg coils on a laying mechanism, and move the laying mechanism or the mold to automatically lay the plurality of prepreg coils on the mold along the length direction of the mold to form a prepreg sheet; the thickness of the prepreg sheet is less than the thickness of the finished stringer;

[0009] Step 3: Move the roller mechanism or the mold to roll and shape the prepreg sheet along the length direction of the mold.

[0010] Step 4: Repeat Step 2 to Step 3 to complete the forming process of the stringer finished product with the required thickness.

[0011] In one embodiment, before Step 3, the prepreg sheet is bent laterally along the length direction of the mold.

[0012] In one embodiment, a roller swing arm is used to perform widthwise rolling and bending on the prepreg sheet according to the shape of the mold.

[0013] In one embodiment, the roller swing arm includes a handle, a roller, a connecting swing arm, and an elastic member; both ends of the roller are respectively connected to the handle through the connecting swing arm; the elastic member is arranged between the connecting swing arms on the same side of the two rollers.

[0014] In one embodiment, the roller swing arm includes a base, a swing arm link assembly, and a roller; the swing arm link assembly is arranged on the base and includes a first connecting rod, a second connecting rod, a motor, and a pressing device; one end of the first connecting rod is rotatably connected to the base, and the other end of the first connecting rod is rotatably connected to one end of the second connecting rod; the other end of the second connecting rod is provided with the roller; the motor is used to drive the first connecting rod to rotate; the movable end of the pressing device is fixed at the middle position of the second connecting rod, and the fixed end is rotatably connected to the base for providing the pressure to press down the roller.

[0015] In one embodiment, the roller mechanism is located behind the laying mechanism, and the roller mechanism synchronizes with the laying mechanism to perform operations, automatically laying and roll-forming along the length direction of the mold.

[0016] In one embodiment, the laying mechanism includes a mounting shaft and a cloth pressing wheel. A plurality of the mounting shafts are arranged from bottom to top for mounting a plurality of prepreg coils; the axis of the cloth pressing wheel is parallel to the axis of the mounting shaft, and the lower end surface of the cloth pressing wheel is lower than the lower end surface of the lowermost mounting shaft after mounting the prepreg coil.

[0017] As a second aspect, the present invention provides another method for forming a stringer-shaped composite material, including:

[0018] Step 1: Cut the width of the prepreg sheet according to the shape of the mold and the stringer finished product; the thickness of the prepreg sheet is less than the thickness of the stringer finished product.

[0019] Step 2: Lay the prepreg sheet on the mold, and move the roller mechanism or the mold to roll and shape the prepreg sheet along the length direction of the mold;

[0020] Step 3: Repeat Step 2 to complete the forming process of the stringer finished product with the required thickness.

[0021] In one embodiment, the roller mechanism includes a front roller, a rear roller, and a connecting frame connecting the front roller and the rear roller; grooves matching the cross-sectional shape of the mold are provided on both the front roller and the rear roller; the front roller is a hot roller and the rear roller is a cold roller; the front roller first heats and rolls the prepreg sheet, and the rear roller cools and rolls the portion that has been rolled by the front roller for shaping.

[0022] In one embodiment, the prepreg sheet is a multi-layer prepreg structure, and the prepreg includes one or several of unidirectional fiber prepreg, square prepreg, twill prepreg, or multi-axial prepreg.

[0023] As a third aspect, the present invention also provides a forming process for a stringer-shaped composite material, which is used for the forming process of a stringer finished product with a T-shaped or I-shaped cross-section, and includes:

[0024] Step 1: Use the forming process for a stringer-shaped composite material as described in the first aspect or the second aspect to complete the forming process of an L-shaped or C-shaped semi-finished product with the required thickness;

[0025] Step 2: Close two of the L-shaped or C-shaped semi-finished products into a T-shaped or I-shaped shape, and lay a prepreg sheet with the same thickness as the L-shaped or C-shaped semi-finished product on the end faces where the two L-shaped or C-shaped semi-finished products are coplanar and roll it to complete the forming process of the T-shaped or I-shaped stringer finished product.

[0026] Compared with the prior art, the present invention has the following beneficial effects:

[0027] 1. The forming process for a stringer-shaped composite material provided by the present invention all adopts the method of multiple layering and multiple rolling and forming, which can avoid the phenomenon that fibers are twisted and wrinkled at the bending part due to the excessive thickness of the prepreg sheet during single rolling, ensure the quality of the composite material forming process, and guarantee the strength of the final stringer finished product;

[0028] 2. Before the roller mechanism performs the rolling and shaping operation, the present invention first pre-bends the prepreg sheet (which can also be called side rolling or width rolling), which can ensure that the sheet does not deform in the length direction during single rolling, further ensure the quality of the composite material forming process, and guarantee the strength of the final stringer finished product;

[0029] 3. The roller mechanism of the present invention follows closely behind the cloth pressing wheel. The roller mechanism and the cloth pressing wheel as a whole move relative to the mold together, enabling the rolling operation to follow closely after the laying operation, achieving the effect of rolling while laying, and significantly improving the production efficiency of the stringer product.

[0030] 4. The design of the installation shaft and the cloth pressing wheel of the laying mechanism of the present invention can ensure that the cloth pressing wheel automatically completes the simultaneous laying of multiple prepreg coils along the length direction of the mold when the laying mechanism moves relative to the mold. Compared with the traditional method of laying prepreg coils layer by layer, it can achieve one-time multi-layer laying and improve the laying efficiency.

[0031] 5. The laying equipment, roller mechanism, and roller arm used in the present invention are all simple in structure, easy to operate, low in cost, and have no restrictions on the size of the stringer. They can be applied to the forming of stringer parts of various sizes or particularly complex shapes, with a wide range of applications and universality. Description of the Drawings

[0032] Figure 1 It shows a schematic diagram of the simultaneous automatic laying of multiple prepreg coils using the laying mechanism in Embodiment 1 of the present invention.

[0033] Figure 2 It shows a schematic diagram of rolling the prepreg sheet using the roller mechanism in Embodiment 1 or Embodiment 4 of the present invention.

[0034] Figure 3 It shows a schematic diagram of width rolling using the first embodiment of the roller arm in Embodiment 2 of the present invention.

[0035] Figure 4 It shows a schematic diagram of width rolling using the second embodiment of the roller arm in Embodiment 2 of the present invention.

[0036] Figure 5 It shows a schematic diagram of the state before or after starting or ending the width rolling using the second embodiment of the roller arm in Embodiment 2 of the present invention.

[0037] Figure 6 It shows a schematic diagram of rolling the bent prepreg sheet using the roller mechanism in Embodiment 2 of the present invention.

[0038] Figure 7 It shows a schematic diagram of laying and rolling simultaneously using the laying mechanism and the roller mechanism in Embodiment 3 of the present invention.

[0039] Figure 8 It shows a schematic diagram of the processing flow for forming the finished T-shaped stringer in Embodiment 5 of the present invention.

[0040] Figure 9 It shows a schematic diagram of the processing flow for forming the finished I-shaped stringer in Embodiment 6 of the present invention.

[0041] In the figure: 10, a mold; 20, a laying mechanism; 21, a mounting shaft; 22, a cloth pressing wheel; 30, a roller mechanism; 31, a front roller; 32, a rear roller; 33, a connecting frame; 40 or 50, a roller swing arm; 41, a handle; 42 or 53, a roller; 43, a connecting swing arm; 51, a base; 52, a swing arm linkage assembly; 521, a first connecting rod; 522, a second connecting rod; 523, a rotating shaft; 524, a pressing device;

[0042] A, prepreg coil; B, prepreg sheet. Specific embodiments

[0043] Please refer to Figures 1-9 The following specific examples illustrate the embodiments of the present invention. Those skilled in the art can easily understand other advantages and effects of the present invention from the content disclosed in this specification.

[0044] It should be noted that the structures, ratios, sizes, etc. shown in the drawings of this specification are only used to cooperate with the content disclosed in the specification for those skilled in the art to understand and read, and are not used to limit the limiting conditions for the implementation of the present invention. Therefore, they do not have a substantial technical meaning. Any modification of the structure, change in the proportional relationship, or adjustment of the size, without affecting the effects that the present invention can produce and the purposes that can be achieved, should still fall within the scope covered by the technical content disclosed in the present invention.

[0045] Unless otherwise defined, the technical terms or scientific terms used herein should be understood as having the ordinary meaning as understood by those of ordinary skill in the art to which the present invention pertains. The terms "a", "one", or "the" and the like used in the present invention do not indicate a limitation in quantity, but only indicate the existence of at least one. The terms "comprising" or "including" and the like mean that the elements or objects appearing before the term cover the elements or objects listed after the term and their equivalents, without excluding other elements or objects. The serial numbers assigned to the components in this specification, such as "first", "second", etc., are only used to distinguish the described objects and do not have any sequential or technical meaning. And the "connection" mentioned in the present invention, unless otherwise specified, includes both direct and indirect connections. The "front" and "rear" used in the present invention represent the directions of operation execution, with the earlier operation in the front and the later operation in the rear.

[0046] In order to avoid confusion with the present invention, some well-known technical features in the art are not described.

[0047] (Example 1)

[0048] As Figures 1-2As shown, this embodiment provides a method for forming and processing a stringer-shaped composite material, which is used for automatically laying and roll-forming a prepreg that has not yet formed a prepreg sheet B, and includes the steps:

[0049] S101. Cut the prepreg to a fixed width according to the mold 10 and the shape of the stringer finished product, and roll it into a prepreg coil A;

[0050] The cross-sectional shape of the mold 10 can be Ω-shaped, C-shaped, L-shaped, etc., and the corresponding cross-sectional shapes of the stringer finished products can be Ω-shaped, C-shaped, and L-shaped respectively.

[0051] The prepreg is made by impregnating continuous fibers or fabrics with a resin matrix under strictly controlled conditions to form a composition of the resin matrix and the reinforcement. Among them, the resin matrix includes but is not limited to epoxy resin, bismaleimide resin, polyimide resin, phenolic resin, etc.; the reinforcement includes but is not limited to carbon fiber, glass fiber, aramid fiber, etc., and the common forms of the reinforcement are unidirectional fiber, square cloth, twill cloth, multi-axial cloth, etc.

[0052] The prepreg can be one or several of unidirectional fiber prepreg, square prepreg, twill prepreg or multi-axial prepreg. In this embodiment, the square prepreg, twill prepreg or multi-axial prepreg is an interleaved prepreg, that is, it is formed by interleaving unidirectional fiber prepregs at different angles. Among them, the square prepreg is formed by interleaving 0° unidirectional fiber prepreg and 90° unidirectional fiber prepreg; the twill prepreg is formed by interleaving 0° unidirectional fiber prepreg and ±45° unidirectional fiber prepreg; the multi-axial prepreg is formed by interleaving unidirectional fiber prepregs at at least three angles.

[0053] In some other embodiments, the square prepreg, twill prepreg or multi-axial prepreg can also be a fabric prepreg, that is, first weave the reinforcement into fabrics such as square cloth, twill cloth and multi-axial cloth, and then impregnate the fabric with a resin matrix under strictly controlled conditions to form a fabric prepreg.

[0054] S102. Install a plurality of prepreg coils A on the laying mechanism 20, move the laying mechanism 20 or the mold 10 to automatically lay the plurality of prepreg coils A on the mold 10 along the length direction of the mold 10 to form a prepreg sheet B; the thickness of the prepreg sheet B is less than the thickness of the stringer finished product;

[0055] Specifically, a plurality of mounting shafts 21 arranged from bottom to top are provided on the laying mechanism 20 for mounting a plurality of prepreg coils A. Although in this embodiment, the axial center distances of the plurality of mounting shafts 21 are equal, and the axial center connection line of the plurality of mounting shafts 21 is a vertical line, this is not necessary. In other embodiments, the axial center distances of the plurality of mounting shafts 21 may also be unequal; the axial center connection line of the plurality of mounting shafts 21 may be an oblique line, or the axial centers of the plurality of mounting shafts 21 may not be collinear. A cloth pressing wheel 22 is also provided on the laying mechanism 20. The axis of the cloth pressing wheel 22 is parallel to the axis of the mounting shaft 21, and the lower end surface of the cloth pressing wheel 22 is lower than the lower end surface of the lowermost mounting shaft 21 after mounting the prepreg coil A. When automatic laying is performed, one end of the plurality of prepreg coils A is placed layer by layer between the mold 10 and the cloth pressing wheel 22. The cloth pressing wheel 22 presses one end of the plurality of prepreg coils A against the mold 10, and the axis of the cloth pressing wheel 22 is perpendicular to the length direction of the mold 10; when the laying mechanism 20 and the mold 10 move relative to each other, the cloth pressing wheel 22 automatically completes the simultaneous laying of the plurality of prepreg coils A along the length direction of the mold 10. Compared with the traditional method of laying prepreg coils A layer by layer, it can achieve multi-layer laying at one time and improve the laying efficiency.

[0056] The laying mechanism 20 can be designed to move by itself with moving wheels, or the laying mechanism 20 can be driven by a moving trolley to move; the movement of the mold 10 mainly depends on the moving trolley to move. Further, in order to ensure the stability of the moving track, the movement of both the laying mechanism 20 and the mold 10 can be designed as fixed-track movement. For example, when the laying mechanism 20 moves and the mold 10 is at a fixed station, the laying mechanism 20 can first move along the width direction of the mold 10 to the laying starting position, and then move along the length direction of the mold 10 to complete the laying. Another example is when the mold 10 moves and the laying mechanism 20 is at a fixed station. The moving trolley of the mold 10 can be a track vehicle. The preset tracks of the track vehicle include a first track designed along the width direction of the mold 10 and a second track designed along the length direction of the mold 10; when the track vehicle moves along the first track, it can move the mold 10 into or out of the area below the cloth pressing wheel 22 of the laying mechanism 20; when the track vehicle moves along the second track, it can enable the cloth pressing wheel 22 to automatically complete the laying of the plurality of prepreg coils A along the length direction of the mold 10.

[0057] Further, the laying mechanism 20 can rotate and traverse conformally to adapt to the production of different stringers, including warped parts and side-rotated parts.

[0058] S103. The moving roller mechanism 30 or the mold 10 performs rolling and shaping on the prepreg sheet B along the length direction of the mold 10;

[0059] The roll forming operation can be carried out by a dedicated roller mechanism 30. The roller mechanism 30 includes a front roller 31, a rear roller 32, and a connecting frame 33 connecting the front roller 31 and the rear roller 32. Grooves matching the cross-sectional shape of the mold 10 are provided on both the front roller 31 and the rear roller 32. The front roller 31 is a hot roller, and the rear roller 32 is a cold roller. The front roller 31 first heats and rolls the bent prepreg sheet B, and the rear roller 32 cools and rolls the part of the prepreg sheet B that has been rolled by the front roller 31 to complete the shaping. The shaping of the prepreg sheet B can be completed by the secondary rolling of the front and rear rollers 32 of the roller mechanism 30.

[0060] S104. Repeat S102 and S103 to complete the forming process of the stringer finished product with the required thickness.

[0061] In Example 1, the method of multiple automatic laying and multiple roll forming can avoid the phenomenon that the fibers are twisted and wrinkled at the bending part due to the excessive thickness of the prepreg sheet B during single roll forming, ensure the quality of the composite material forming process, and guarantee the strength of the final stringer finished product.

[0062] (Example 2)

[0063] As Figures 3-6 shown, this embodiment provides a method for forming a stringer-shaped composite material, which is used for automatically laying and roll forming a prepreg that has not yet formed a prepreg sheet B, including the steps:

[0064] S201. Cut the prepreg to a fixed width according to the mold 10 and the shape of the stringer finished product, and roll it into a prepreg coil A.

[0065] S202. Install multiple prepreg coils A on the laying mechanism 20, and move the laying mechanism 20 or the mold 10 to automatically lay multiple prepreg coils A on the mold 10 along the length direction of the mold 10 to form a prepreg sheet B. The thickness of the prepreg sheet B is less than the thickness of the stringer finished product.

[0066] S203. Move the roller swing arm or the mold 10 to bend the prepreg sheet B along the length direction of the mold 10.

[0067] The bending operation can be carried out by a dedicated roller swing arm. The roller of the roller swing arm can roll conformally according to the shape of the mold 10 to complete the bending of the prepreg sheet B.

[0068] As shown in Figure 3, in the first embodiment of the roller swing arm, the roller swing arm 40 may include a handle 41, two rollers 42, four connecting swing arms 43 and two elastic members; both ends of the roller 42 are respectively connected to the handle 41 through a connecting swing arm 43; elastic members, such as springs, are provided between the connecting swing arms 43 on the same side of different rollers 42. The function of the elastic members is to apply a converging elastic force to the two downwardly pressed and separated rollers 42 to ensure that the rollers 42 tightly press the prepreg sheet B on the mold 10 and guarantee the bending effect. When holding the handle 41 and pressing down the rollers 42, the two rollers 42 can be symmetrically and vertically pressed down so that the two rollers 42 simultaneously roll along the shape of the mold 10 to bend both ends of the prepreg sheet B; or the two rollers 42 can be pressed down obliquely so that one roller 42 first rolls along the shape of the mold 10 to bend one end of the prepreg sheet B, and the other roller 42 first plays a role in pressing and fixing, and then the force is applied in the opposite way to complete the bending of the other end of the prepreg sheet B.

[0069] Also, as Figure 4 and Figure 5 shown, in the second embodiment of the roller swing arm, the roller swing arm 50 may include a base 51, a swing arm link assembly 52 and a roller 53. The swing arm link assembly 52 is arranged on the base 51. The swing arm link assembly 52 includes a pair of first connecting rods 521, a pair of second connecting rods 522, a pair of rotating shafts 523 and a pair of pressing devices 524; one end of the first connecting rod 521 is rotatably connected to the base 51 through an ear plate and a rotating shaft 523, and the other end of the first connecting rod 521 is rotatably connected to one end of the second connecting rod 522 through another rotating shaft 523; the rotating shaft 523 is used to connect two symmetrically arranged first connecting rods 521, and a motor for driving its rotation is connected to the rotating shaft 523. The motor can provide power for the overall swing movement of the swing arm link assembly 52; the other end of the second connecting rod 522 is provided with a roller 53; the pressing device 524 can be a cylinder, a hydraulic cylinder or an electric cylinder, and its movable end is fixed at the middle position of the second connecting rod 522, and the fixed end is rotatably connected to the base 51 through an ear plate. The pressing device 524 is arranged close to the roller 53 side, and its function is to provide the pressure for pressing down the roller 53.

[0070] When performing the bending operation, a roller swing arm 50 needs to be symmetrically arranged on both sides in the width direction of the mold 10. The first connecting rod 521 is driven by a motor to rotate towards the mold 10, driving the second connecting rod 522 and the roller 53 to press the prepreg sheet B against the mold 10. Then, the pressing device 524 drives the second connecting rod 522 to move downward, driving the roller 53 to roll along the shape of the mold 10 to bend both ends of the prepreg sheet B. During the downward pressing process of the roller 53, the first connecting rod 521 and the second connecting rod 522 will perform a matching linkage rotation according to the shape of the mold 10. The rolling operations of the roller swing arms 50 on both sides can be carried out simultaneously or separately. After the rolling and bending are completed, the swing arm linkage assembly 52 can be rotated and opened away from the mold 10 through the motor and the pressing device 524, facilitating subsequent operations, such as the hoisting of the mold 10 and the formed workpiece, etc.

[0071] S204. Move the roller mechanism 30 or the mold 10, and roll and shape the bent prepreg sheet B along the length direction of the mold 10;

[0072] S205. Repeat S202 - S204 to complete the forming process of the long truss finished product with the required thickness.

[0073] The mold 10, prepreg, laying mechanism 20, and roller mechanism 30 used in Embodiment 2 can all be the same as those in Embodiment 1, and will not be elaborated here.

[0074] The difference between Embodiment 2 and Embodiment 1 is that: before the roller mechanism 30 performs the rolling and shaping operation in Embodiment 2, the prepreg sheet B is pre - bent (which can also be called side rolling or width rolling). This design can ensure that the sheet does not deform in the length direction during a single rolling, further ensuring the quality of the composite material forming process and guaranteeing the strength of the final long truss finished product.

[0075] (Embodiment 3)

[0076] As Figure 7 shown, a method for forming a long truss - shaped composite material provided in this embodiment is used for automatically laying and rolling and forming a prepreg that has not yet formed a prepreg sheet B, and includes the steps:

[0077] S301. Cut the width of the prepreg according to the mold 10 and the shape of the long truss finished product, and roll it into a prepreg coil A;

[0078] S302. Install multiple prepreg coils A on the laying mechanism 20, and move the laying mechanism 20 or the mold 10 to automatically lay multiple prepreg coils A on the mold 10 along the length direction of the mold 10 to form a prepreg sheet B; the roller mechanism 30 behind the laying mechanism 20 simultaneously rolls and shapes the prepreg sheet B; among them, the thickness of the prepreg sheet B is less than the thickness of the long truss finished product;

[0079] S303. Repeat S302 to complete the forming process of the stringer finished product with the required thickness.

[0080] The mold 10, prepreg, laying mechanism 20, and roller mechanism 30 used in Example 3 are the same as those in Example 1, and will not be elaborated here.

[0081] The difference between Example 3 and Example 1 is that: the roller mechanism 30 in Example 3 follows closely behind the cloth pressing wheel 22, and the roller mechanism 30 and the cloth pressing wheel 22 move together relative to the mold 10 as a whole, so that the rolling operation follows closely after the laying operation, achieving the effect of rolling while laying, which can significantly improve the production efficiency of the stringer product.

[0082] (Example 4)

[0083] As Figure 2 shown, a method for forming a stringer-shaped composite material provided in this embodiment is used for roll forming of a prepreg sheet B, including the steps:

[0084] S401. Cut the width of the prepreg sheet B according to the mold 10 and the shape of the stringer finished product; the thickness of the prepreg sheet B is less than the thickness of the stringer finished product.

[0085] The prepreg sheet B is a multi-layer prepreg structure, and may include one or several of unidirectional fiber prepreg, square prepreg, twill prepreg, or multi-axial prepreg.

[0086] S402. Lay the prepreg sheet B on the mold 10, and move the roller mechanism 30 or the mold 10 to roll and shape the prepreg sheet B along the length direction of the mold 10.

[0087] S403. Repeat S402 to complete the forming process of the stringer finished product with the required thickness.

[0088] The mold 10 and the roller mechanism 30 used in Example 4 are the same as those in Example 1, and will not be elaborated here.

[0089] The difference between Example 4 and Example 1 is that: Example 4 directly uses a multi-layer prepreg sheet B, eliminating the step of moving and laying the multi-layer prepreg using the laying mechanism 20 compared to Example 1.

[0090] (Example 5)

[0091] As Figure 8 shown, a method for forming a stringer-shaped composite material provided in this embodiment is used for forming a stringer finished product with a T-shaped cross-section, including the steps:

[0092] S501, using the method of any one of Embodiments 1 to 4 to complete the L-shaped semi-finished product forming process of the required thickness;

[0093] S502, folding two L-shaped semi-finished products into a T shape, and laying a prepreg sheet B with the same thickness as the L-shaped semi-finished product on one end of the two L-shaped semi-finished products on the same plane and rolling them to complete the molding process of the T-shaped long stringer finished product.

[0094] Specifically, during the L-shaped semi-finished product forming process, the two L-shaped molds 10 can be rotatably connected in advance through a rotating part, and the two L-shaped molds 10 can be placed in an M shape, and the material laying and roller forming are completed on the two L-shaped molds 10 respectively, so as to form two L-shaped semi-finished products simultaneously; then the two L-shaped molds 10 placed in the M shape are rotated toward each other and closed with the rotating part as the rotation center to form a T-shaped semi-finished product; then, a prepreg sheet B with the same thickness as the L-shaped semi-finished product is laid on the upper end plane of the T-shaped semi-finished product; finally, the T-shaped long stringer finished product is demolded.

[0095] (Example 6)

[0096] like Figure 9 As shown, a method for forming a long-beam composite material provided in this embodiment is used for forming a long-beam finished product with an I-shaped cross-section, comprising the steps of:

[0097] S601, using the method of any one of Embodiments 1 to 4 to complete the C-shaped semi-finished product forming process of the required thickness;

[0098] S602, folding two C-shaped semi-finished products into an I-shape, and laying prepreg sheets B with the same thickness as the C-shaped semi-finished products at both ends of the coplanar surface of the two C-shaped semi-finished products and rolling them to complete the molding process of the I-shaped long stringer finished product.

[0099] Specifically, during the C-type semi-finished product forming process, two C-type molds 10 can be placed side by side in advance, with the notches of the two C-type molds 10 facing downward, and the material laying and roller forming are completed on the two C-type molds 10 respectively, so that two C-type semi-finished products are formed simultaneously; then the two C-type molds 10 are rotated 90° clockwise and counterclockwise respectively, so that the upward surfaces of the C-type molds 10 when laying the materials are closed, and at this time the two C-type semi-finished products are assembled into an I-shaped semi-finished product; then, a prepreg sheet B with the same thickness as the C-type semi-finished product is laid on the upper end plane of the I-shaped semi-finished product and rolled; then the whole is rotated 180°, so that the lower end plane of the I-shaped semi-finished product faces upward, and a prepreg sheet B with the same thickness as the C-type semi-finished product is laid and rolled; finally, the I-shaped long girder is demolded to obtain a finished product.

[0100] In summary, the stringer-shaped composite material forming and processing methods adopted in the above Embodiments 1 to 6 all use the method of multiple layups and multiple rollings to form, which can avoid the phenomenon that the fibers are twisted and wrinkled at the bending places due to the excessive thickness of the prepreg sheet B during single rolling, ensure the quality of the composite material forming and processing, and guarantee the strength of the final stringer product. At the same time, the laying equipment, the roller mechanism 30 and the roller swing arm adopted in each embodiment are all simple in structure, easy to operate, low in cost, and have no limitation on the size of the stringer, and can be applied to the forming of various sizes or particularly complex-shaped stringer parts, with a wide application range and universality.

[0101] Therefore, the present invention effectively overcomes various disadvantages in the prior art and has high industrial utilization value. The above embodiments are only illustrative of the principles and effects of the present invention and are not intended to limit the present invention. Any person familiar with this technology can modify or change the above embodiments without departing from the spirit and scope of the present invention. Therefore, all equivalent modifications or changes completed by those with ordinary knowledge in the technical field without departing from the spirit and technical idea disclosed by the present invention should still be covered by the claims of the present invention.

Claims

1. A method for forming a long-beam composite material, comprising: Step 1: Cut the prepreg to a certain width according to the shape of the mold and the finished long stringer, and roll it into a prepreg coil; Step 2: installing a plurality of the prepreg coils on a material laying mechanism, and moving the material laying mechanism or the mold so that the plurality of the prepreg coils are automatically laid on the mold along the length direction of the mold to form a prepreg sheet; the thickness of the prepreg sheet is less than the thickness of the finished stringer; Step 3, moving the roller mechanism or the mold to roll and shape the prepreg sheet along the length direction of the mold; Step 4: Repeat steps 2 to 3 to complete the molding process of the long stringer product of required thickness.

2. The long-string composite material forming processing method according to claim 1, characterized in that: Before the step three, the prepreg sheet is first bent sideways along the length direction of the mold.

3. The long-string composite material forming and processing method according to claim 2, characterized in that: The prepreg sheet is rolled and bent in width according to the shape of the mold by using a roller swing arm.

4. The long-string composite material forming method according to claim 3, characterized in that: The roller swing arm comprises a handle, a roller, a connecting swing arm and an elastic member; both ends of the roller are connected to the handle through the connecting swing arm respectively; The elastic member is arranged between the connecting swing arms on the same side of the two rollers.

5. The long-string composite material forming processing method according to claim 3, characterized in that: The roller swing arm includes a base, a swing arm connecting rod assembly and a roller; the swing arm connecting rod assembly is arranged on the base, and includes a first connecting rod, a second connecting rod, a motor and a pressure device; one end of the first connecting rod is rotatably connected to the base, and the other end of the first connecting rod is rotatably connected to one end of the second connecting rod; the roller is installed on the other end of the second connecting rod; the motor is used to drive the first connecting rod to rotate; the movable end of the pressure device is fixed at the middle section of the second connecting rod, and the fixed end is rotatably connected to the base, which is used to provide pressure to press down the roller.

6. The long-string composite material forming method according to claim 1, characterized in that: The roller mechanism is located behind the material spreading mechanism, and the roller mechanism operates synchronously with the material spreading mechanism, and automatically spreads the material and rolls and shapes it along the length direction of the mold.

7. The long-string composite material forming processing method according to claim 1 or 6, characterized in that: The material laying mechanism includes a mounting shaft and a cloth pressing wheel. A plurality of the mounting shafts are arranged from bottom to top for mounting a plurality of the prepreg coils. The axis of the cloth pressing wheel is parallel to the axis of the mounting shaft, and the lower end surface of the cloth pressing wheel is lower than the lower end surface of the lowest mounting shaft after mounting the prepreg coil.

8. A method for forming a long-beam composite material, comprising: Step 1: cutting the prepreg sheet to a fixed width according to the shapes of the mold and the finished long stringer; the thickness of the prepreg sheet is less than the thickness of the finished long stringer; Step 2: Laying the prepreg sheet on the mold, moving the roller mechanism or the mold, and rolling and shaping the prepreg sheet along the length direction of the mold; Step 3: Repeat step 2 to complete the molding process of the long stringer finished product of required thickness.

9. The long-string composite material forming and processing method according to claim 1, 6 or 8, characterized in that: The roller mechanism includes a front roller, a rear roller, and a connecting frame connecting the front roller and the rear roller; the front roller and the rear roller are both provided with grooves matching the cross-sectional shape of the mold; the front roller is a hot roller, and the rear roller is a cold roller; the front roller first heats and rolls the prepreg sheet, and the rear roller cools and rolls the portion that has been rolled by the front roller to shape it.

10. The long-string composite material forming method according to claim 1 or 8, characterized in that: The prepreg sheet is a multi-layer prepreg structure, and the prepreg includes one or more of unidirectional fiber prepreg, lattice prepreg, twill prepreg or multi-axial prepreg.

11. A method for forming a long-beam composite material, used for forming a long-beam finished product with a T-shaped or I-shaped cross-section, comprising: Step 1: using the long-beam composite material forming processing method as described in any one of claims 1 to 10 to complete the L-shaped or C-shaped semi-finished product forming processing of the required thickness; Step 2: bring the two L-shaped or C-shaped semi-finished products together to form a T-shape or an I-shape, and lay a prepreg sheet with the same thickness as the L-shaped or C-shaped semi-finished product on the coplanar end surfaces of the two L-shaped or C-shaped semi-finished products and roll them to complete the molding process of the T-shaped or I-shaped long stringer finished product.

Images