Composite material blade forming mold, device and method

Abstract

The invention provides a composite material blade forming mold, device and method, the composite material blade forming mold comprises a blade basin side mold, a blade back side mold and a pin shaft, and the blade basin side mold and the blade back side mold are connected through the pin shaft and are switched between a mold opening state and a mold closing state through rotation around the axis of the pin shaft. The blade basin side mold is provided with a first cavity surface used for forming at least part of a blade basin surface of the composite material blade, the blade back side mold is provided with a second cavity surface used for forming at least part of a blade back surface of the composite material blade, and in a mold closing state, a cavity used for forming the composite material blade is defined by the first cavity surface and the second cavity surface; in the process of switching from the mold opening state to the mold closing state, the composite material blade is gradually compacted and formed in the direction from the front edge to the tail edge, the effect of stroking a composite material laying layer from front to back is achieved, the risk that laying layer wrinkles appear on the front edge and the nearby position of the blade is reduced, and the wrinkling position is concentrated on the tail edge position with the low profile requirement.

Description

Technical Field

[0001] The present invention relates to the technical field of composite blade manufacturing, and more specifically, to a composite blade forming mold, device and method. Background Art

[0002] The hot-end components of aero-engines and gas turbines need to withstand relatively high ambient temperatures. For high-temperature resistant blades, under the conditions of traditional cooling technology and thermal barrier coating technology, the service temperature and performance of traditional superalloy materials have approached their limits. Ceramic matrix composites (CMC) have the advantages of high temperature resistance, corrosion resistance and low density, and have become an excellent choice for hot-end components such as turbines and compressor blades.

[0003] To improve the working efficiency of aero-engines and gas turbines, the hot-end blade structures often have complex aerodynamic shapes.

[0004] Ceramic matrix composite blades are usually formed by laying multiple composite layers, and then subsequent curing and infiltration work is carried out. The accuracy of the laying has a great influence on the surface accuracy of the final product. After the laying is completed, a molding process is required. However, the ductility of the ceramic matrix composite laying layer is poor, and defects such as wrinkles and cavities may be formed during the process of laying blades with complex shapes. In the subsequent molding process, due to the difficulty of applying uniform force to the complex curved surface of the blade shape, the formation of laying wrinkles will be aggravated. Summary of the Invention

[0005] The purpose of the present invention is to provide a composite blade forming mold, which can solve the technical problem that defects such as laying wrinkles are likely to occur during the forming process of blades with complex shapes in the existing technology.

[0006] The purpose of the present invention is also to provide a composite blade forming device, which can solve the technical problem that defects such as laying wrinkles are likely to occur during the forming process of blades with complex shapes in the existing technology.

[0007] The purpose of the present invention is also to provide a composite blade forming device, which can solve the technical problem that defects such as laying wrinkles are likely to occur during the forming process of blades with complex shapes in the existing technology.

[0008] The embodiments of the present invention can be implemented in the following ways:

[0009] A composite blade forming mold for forming a composite blade. The composite blade has a suction surface and a pressure surface, and a leading edge is formed at the connection of one end of the suction surface and the pressure surface, and a trailing edge is formed at the connection of the other end; the composite blade forming mold includes:

[0010] The blade basin side mold, the blade basin side mold has a first cavity surface, and the first cavity surface is used for forming at least a part of the blade basin surface;

[0011] The blade back side mold, the blade back side mold has a second cavity surface, and the second cavity surface is used for forming at least a part of the blade back surface; and

[0012] The pin shaft, the pin shaft cooperates with the blade basin side mold and the blade back side mold at the same time, so that the blade basin side mold and the blade back side mold can rotate around the axis of the pin shaft, so that the composite material blade forming mold can be switched between the open mold state and the closed mold state;

[0013] Wherein, in the closed mold state, the first cavity surface and the second cavity surface enclose the cavity for forming the composite material blade, and the cavity has a front end for forming the leading edge and a tail end for forming the trailing edge; the pin shaft is located on one side of the front end, so as to gradually compact and form the composite material blade in the direction from the leading edge to the trailing edge during the process of switching from the open mold state to the closed mold state.

[0014] Optionally, the blade basin side mold and the blade back side mold further form a cavity at the tail end in the closed mold state, and the cavity communicates with the cavity.

[0015] Optionally, the blade back side mold has a first rotation mating surface, and the blade basin side mold has a second rotation mating surface; both the first rotation mating surface and the second rotation mating surface are arc surfaces arranged around the axis of the pin shaft, and during the process of switching to the closed mold state, the first rotation mating surface and the second rotation mating surface remain in contact.

[0016] Optionally, the intersection line of the first rotation mating surface and the cavity is the leading edge line of the cavity; the intersection line of the second rotation mating surface and the cavity is the leading edge line of the cavity.

[0017] Optionally, the blade back side mold is provided with a rocker arm part, the blade basin side mold is provided with a first shaft hole section in the height direction, and the rocker arm part is provided with a second shaft hole section, and the first shaft hole section and the second shaft hole section communicate to form a mounting hole for mounting the pin shaft.

[0018] Optionally, one side of the rocker arm part close to the cavity has a first mating plane, and the blade basin side mold has a second mating plane that mates with the first mating plane. In the closed mold state, there is a gap between the first mating plane and the second mating plane.

[0019] Optionally, the back-side die of the blade includes a plurality of first sub-dies stacked in the height direction; the plurality of first sub-dies are fixed into one body by first fasteners.

[0020] Optionally, the front-side die of the blade includes a plurality of second sub-dies stacked in the height direction; the plurality of second sub-dies are fixed into one body by second fasteners.

[0021] Optionally, the position of the axis of the pin shaft satisfies the following conditions:

[0022] On any height section, the axis is located in front of the normal line passing through any point on the first cavity surface; the axis is located inside the tangent line of the mold closing point; wherein, the mold closing point is the contact point between the first cavity surface and the second cavity surface on the side close to the front end.

[0023] A composite material blade forming device, the composite material blade forming device includes a support frame and the above-mentioned composite material blade forming die, and the support frame is used to fix the front-side die of the composite material forming die.

[0024] A composite material blade forming method, the composite material blade forming method includes:

[0025] Press the front-side die on the front side of the blank to form the front blade surface through the first cavity surface of the front-side die;

[0026] Rotate and connect the back-side die to the front-side die through a pin shaft;

[0027] Drive the back-side die to rotate relative to the front-side die around the pin shaft, so that the second cavity surface of the back-side die compacts from the leading edge to the trailing edge of the blank until the back-side die and the front-side die are closed.

[0028] The beneficial effects of the composite material blade forming die, device and method provided by the embodiments of the present invention include:

[0029] Embodiments of the present invention provide a composite material blade forming mold, which includes a blade concave side mold, a blade convex side mold, and a pin shaft. The blade concave side mold and the blade convex side mold are connected by the pin shaft and can be switched between an open mold state and a closed mold state by rotating around the axis of the pin shaft. The blade concave side mold has a first cavity surface for forming at least a part of the blade concave surface of the composite material blade, and the blade convex side mold has a second cavity surface for forming at least a part of the blade convex surface of the composite material blade. In the closed mold state, the first cavity surface and the second cavity surface enclose a cavity for forming the composite material blade. At the same time, the cavity has a front end for forming the leading edge of the composite material blade and a tail end for forming the trailing edge of the composite material blade. The pin shaft is located on one side of the front end. Therefore, during the process of switching from the open mold state to the closed mold state, the composite material blade is gradually compacted and formed in the direction from the leading edge to the trailing edge, achieving the effect of smoothing the composite material ply from front to back, reducing the risk of ply wrinkles appearing at the leading edge and nearby positions of the blade, making the wrinkled positions concentrated at the trailing edge with lower contour requirements, and the wrinkled positions being more controllable, thereby improving the manufacturing accuracy of the blade and the aerodynamic efficiency of the blade.

[0030] Embodiments of the present invention also provide a composite material blade forming device, which includes the above-mentioned composite material blade forming mold. Therefore, it also has the beneficial effects of being able to reduce the risk of ply wrinkles appearing at the leading edge and nearby positions of the blade, making the wrinkled positions concentrated at the trailing edge with lower contour requirements, the wrinkled positions being more controllable, and improving the manufacturing accuracy of the blade and the aerodynamic efficiency of the blade.

[0031] Embodiments of the present invention also provide a composite material blade forming method, which includes pressing the blade concave side mold on the blade concave side of the blank to form the blade concave surface through the first cavity surface of the blade mold; rotatably connecting the blade convex side mold to the blade concave side mold through the pin shaft; driving the blade convex side mold to rotate relative to the blade concave side mold around the pin shaft so that the second cavity surface of the blade convex side mold is gradually pressed from the leading edge to the trailing edge of the blank until the blade convex side mold is closed with the blade concave side mold. This composite material forming method enables the composite material blade to be gradually compacted and formed in the direction from the leading edge to the trailing edge, achieving the effect of smoothing the composite material ply from front to back, reducing the risk of ply wrinkles appearing at the leading edge and nearby positions of the blade, making the wrinkled positions concentrated at the trailing edge with lower contour requirements, the wrinkled positions being more controllable, and improving the manufacturing accuracy of the blade and the aerodynamic efficiency of the blade. Description of the Drawings

[0032] After reading the detailed description of the embodiments of the present disclosure in conjunction with the following drawings, the above features and advantages of the present invention can be better understood. In the drawings, the components are not necessarily drawn to scale, and components with similar relevant characteristics or features may have the same or similar reference numerals.

[0033] Figure 1 Shows a typical blade structure;

[0034] Figure 2 shows Figure 1 a schematic cross-sectional view of the blade structure shown in the height direction;

[0035] Figure 3 shows a schematic structural view of a composite material blade forming mold in an open mold state provided according to one aspect of the present invention;

[0036] Figure 4 shows a schematic structural view of a composite material blade forming mold in a closed mold state provided according to one aspect of the present invention;

[0037] Figure 5a shows a positional relationship diagram of a cavity and a pin shaft in a cross-section at a certain blade height in a composite material blade forming mold provided according to one aspect of the present invention;

[0038] Figure 5b shows an optional position area of the axis of the pin shaft in a cross-section at a certain blade height in a composite material blade forming mold provided according to one aspect of the present invention;

[0039] Figure 5c shows an optional position area of the axis of the pin shaft in a cross-section at a certain blade height in a composite material blade forming mold provided according to another aspect of the present invention;

[0040] Figure 6 shows an exploded structural view of a composite material blade forming mold provided according to one aspect of the present invention;

[0041] Figure 7 shows a schematic structural view of another perspective of a composite material blade forming mold in an open mold state provided according to one aspect of the present invention;

[0042] Figure 8 shows a schematic mating structure view of a first middle mold and a second middle mold of a composite material forming mold in an open mold state provided according to one aspect of the present invention;

[0043] Figure 9 shows a schematic mating structure view of a first middle mold and a second middle mold of a composite material forming mold in a closed mold state provided according to one aspect of the present invention.

[0044] Reference numerals:

[0045] 100 - Composite material blade; 111 - Blade body part; 112 - Leading edge line; 113 - Trailing edge; 114 - Suction side; 115 - Pressure side; 116 - Hollow chamber; 200 - Composite material blade forming die; 210 - Suction side die; 211 - First cavity surface; 212 - Second rotation mating surface; 213 - Second upper die; 214 - Second middle die; 215 - Second lower die; 216 - First shaft hole section; 217 - Third shaft hole section; 218 - Second mold closing surface; 219 - Second fastener; 220 - Pressure side die; 221 - Second cavity surface; 222 - First rotation mating surface; 223 - First upper die; 224 - First middle die; 225 - First lower die; 226 - Rocker arm part; 227 - Second shaft hole section; 228 - First mold closing surface; 229 - Gap; 230 - First fastener; 231 - Cavity; 232 - Cavity; 233 - Connection hole; 234 - Pin shaft; 235 - Mold closing bolt; 240 - Core mold; 28 - Mold closing line; 29 - Tangent line; 30 - Normal line. Detailed implementation mode

[0046] The present invention will be described in detail below with reference to the accompanying drawings and specific embodiments. It should be noted that the aspects described below in conjunction with the accompanying drawings and specific embodiments are merely exemplary and should not be construed as imposing any limitation on the protection scope of the present invention.

[0047] In the description of the present invention, it should be noted that if terms such as "upper", "lower", "inner", "outer", "vertical", etc. are used to indicate the orientation or positional relationship, it is based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship in which the product of the present invention is usually placed during use, rather than indicating or implying that the device or element referred to must have a specific orientation or be constructed and operated in a specific orientation. Therefore, it should not be construed as a limitation to the present invention.

[0048] At the same time, it should be noted that if terms such as "first" and "second" are only used for differential description and should not be construed as indicating or implying relative importance.

[0049] In the description of the present invention, it should also be noted that unless otherwise clearly specified or limited, the terms "installation", "connection", and "connection" should be understood in a broad sense. For example, it can be a fixed connection, an integral connection, or a detachable connection; it can be a mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium, or the communication inside two elements, etc. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0050] In the description of the present invention, the possible terms are explained as follows:

[0051] Non-leading-edge stacked airfoil: An airfoil whose leading edge is not a straight stripe.

[0052] Figure 1 A typical blade structure provided in this embodiment Figure 2 shows Figure 1 a schematic cross-sectional view of the shown blade structure in the height direction Figure 3 shows a schematic structural view of the composite material blade forming mold 200 provided in this embodiment in the mold opening state Figure 4 shows a schematic structural view of the composite material blade forming mold 200 provided in this embodiment in the mold closing state. Please refer to Figures 1-4 In this embodiment, a composite material blade forming mold 200 is provided. Correspondingly, a composite material blade forming device (not shown in the figure) is also provided.

[0053] As Figure 1 and Figure 2 show a typical blade structure. This blade is a typical turbine blade and is a hollow structure with a hollow chamber 116. The blade body part 111 of the blade is divided into a suction side and a pressure side. Specifically, the wall surface forming the suction side of the blade body part 111 can be called the suction surface 114, and the wall surface forming the pressure side can be called the pressure surface 115. The connection between the pressure surface 115 and the suction surface 114 at the front side forms the leading edge. Correspondingly, the connection between the pressure surface 115 and the suction surface 114 at the rear side forms the trailing edge 113. Generally, the suction side of the blade is under pressure in the working state, and the suction surface 114 on this side is set as a concave surface, and the corresponding pressure surface 115 is a convex surface. This feature is beneficial to the improvement of aerodynamic efficiency. The leading edge of the blade is formed by the points at the very front of the cross-section of the blade in all height directions (which can be simply referred to as the blade height direction). Therefore, there is a leading edge line 112 at the leading edge, and the leading edge line 112 usually presents a certain arc in the blade height direction (that is, this blade adopts a non-leading-edge stacked airfoil), and this structure is mainly for improving aerodynamic efficiency. The composite material blade forming mold 200 provided in this embodiment is used to form the blade body part 111 of the blade structure as shown in Figure 1 and Figure 2 shown.

[0054] The composite material blade forming device includes the composite material blade forming mold 200. At the same time, the composite material blade forming device also includes a support frame (not shown in the figure). The suction side mold 210 is fixed through the support frame, so that when the pressure side mold 220 rotates relative to the suction side mold 210, the compaction molding of the pressure surface 115 is realized.

[0055] The composite material blade forming die 200 includes a blade concave side die 210, a blade convex side die 220 and a pin shaft 234. The blade concave side die 210 and the blade convex side die 220 are connected by the pin shaft 234 and are switched between an open die state and a closed die state by rotating around the axis of the pin shaft 234. The blade concave side die 210 has a first cavity surface 211 for forming at least a part of the blade concave surface 114 of the composite material blade 100, and the blade convex side die 220 has a second cavity surface 221 for forming at least a part of the blade convex surface 115 of the composite material blade 100. In the closed die state, the first cavity surface 211 and the second cavity surface 221 enclose a cavity 231 for forming the composite material blade 100. At the same time, the cavity 231 has a front end for forming the leading edge of the composite material blade 100 and a tail end for forming the trailing edge 113 of the composite material blade 100. The pin shaft 234 is located on one side of the front end. Thus, in the process of switching from the open die state to the closed die state, the composite material blade 100 is gradually compacted and formed in the direction from the leading edge to the trailing edge 113, achieving the effect of smoothing the composite material ply from front to back, reducing the risk of ply wrinkles appearing at the leading edge position and its vicinity of the blade, making the wrinkled position concentrated at the trailing edge 113 with lower contour requirements, and the wrinkled position being more controllable, improving the blade manufacturing accuracy and the aerodynamic efficiency of the blade.

[0056] Furthermore, in this embodiment, since the composite material blade 100 to be formed has a hollow chamber 116, correspondingly, a core mold 240 for forming the hollow chamber 116 needs to be provided when forming the composite material blade 100. In other words, the composite material forming die provided in this embodiment may further include a core mold 240. It can be understood that in other embodiments, if the composite material blade 100 to be formed does not have a hollow chamber 116, the composite material blade forming die 200 may not be provided with a core mold 240 either.

[0057] Optionally, the core mold 240 can be made of a metal material and is formed by splicing multiple blocks, which is convenient for demolding after the composite material blade 100 is formed. The core mold 240 can also be made of a high-temperature molten material such as resin and removed in the subsequent high-temperature process after the closed die is completed.

[0058] Please continue to refer to Figures 1-4 , in this embodiment, the blade concave side die 210 and the blade convex side die 220 also form a cavity 232 at the tail end in the closed die state. The cavity 232 is communicated with the cavity 231. Thus, in the process of the blade convex side die 220 and the blade concave side die 210 being closed from the front end to the tail end, if there is surplus material after the wrinkles are smoothed out, the surplus material will be extruded into the cavity 232 during the closed die compaction process. After the blade concave surface 114 and the blade convex surface 115 are formed, the surplus material can be removed by machining methods such as cutting to form the trailing edge, thereby further avoiding defects such as wrinkles on the composite material blade 100.

[0059] Figure 5a Shows the positional relationship diagram of the cavity 231 and the pin shaft 234 in a cross-section at a certain blade height in the composite material blade forming die 200 provided in this embodiment. Please refer to Figures 1-5a The installation position of the pin shaft 234 needs to meet the following conditions:

[0060] 1). On any height cross-section, the axis of the pin shaft 234 is located in front of the normal line 30 passing through any point on the first cavity surface 211.

[0061] 2). The axis is located inside the tangent line 29 passing through the mold closing point.

[0062] The mold closing point is the contact point on the side close to the front end of the first cavity surface 211 and the second cavity surface 221. Specifically, as Figure 5a shown, the point C is the position point of the axis on this cross-section, and the point O is the mold closing point on this cross-section.

[0063] Under the condition of satisfying condition 1), for any two points A1 and A2 on the wall surface of the cavity 231 for forming the back of the blade 115, the distance from point A1 to the tangent line 29 passing through point O is L1, the distance from point A2 to the tangent line 29 passing through point O is L2, the distance from point A1 to point C is L3, and the distance from point A2 to point C is L4. When L1 < L2, L3 < L4. In this way, during the rotational mold closing process, the back of the blade 115 will not interfere with the movement of the moving mold (i.e., the back-side mold 220 in this embodiment).

[0064] At the same time, during the process of determining the position of the pin shaft 234, the mold closing point O can be selected first, and then the normal lines are made through the leading edge point and the trailing edge point on this cross-section. The partial area in front of these two normal lines is the preliminary optional position of the axis of the pin shaft 234. Then, through the normal lines 30 of each point on the back of the blade 115, the optional area is narrowed to obtain the axis position area of the pin shaft 234 that meets condition 1) (such as Figure 5b the shaded area 31a shown).

[0065] Under the condition of satisfying condition 2), the direction of the mold closing line 28 at the mold closing point must be an acute angle or a right angle with the tangent line from the mold closing point from front to back, that is, the angle α ≤ 90°. In this way, during mold closing, the fibers at the mold closing point cannot be extruded towards the leading edge direction. Preferably, at the moment of mold closing, there is a backward extrusion force without a forward component. It should be noted that the "mold closing line 28" mentioned here will be described later.

[0066] Under the limitation of the above two conditions, if the mold closing point is located at the leading edge point, the axis of the pin shaft 234 can only be located in Figure 5b the shaded area 31a (including the boundary). If the mold closing point O is moved backward, the corresponding range where the pin shaft 234 can be set increases (such asFigure 5c The shaded area 31b) shown.

[0067] In this embodiment, the mold closing point is located at the leading edge point. Correspondingly, the suction side surface 114 of the composite material blade 100 is formed by the first cavity surface 211, and the pressure side surface 115 of the composite material blade 100 is formed by the second cavity surface 221. It can be understood that in some other embodiments, the mold closing point can also be set at other positions. For example, the mold closing point is set at a position on the pressure side surface 115 close to the leading edge point. At this time, the first cavity surface 211 can be set to form a part of the suction side surface 114 and the pressure side surface 115, and the second cavity surface 221 can be set to form another part of the pressure side surface 115.

[0068] Figure 6 Fig. shows an exploded structural schematic diagram of the composite material blade forming mold 200 provided in this embodiment. Figure 7 Fig. shows another perspective structural schematic diagram of the composite material blade forming mold 200 provided in this embodiment in the mold opening state. Please refer to Figures 1-7 , in this embodiment, the pressure side mold 220 has a first rotational mating surface 222, and the suction side mold 210 has a second rotational mating surface 212. Both the first rotational mating surface 222 and the second rotational mating surface 212 are arc surfaces arranged around the axis of the pin shaft 234, and during the process of switching to the mold closing state, the first rotational mating surface 222 and the second rotational mating surface 212 remain in contact. In this way, through the first rotational mating surface 222 and the second rotational mating surface 212, the rotational stability when the pressure side mold 220 and the suction side mold 210 rotate relative to each other is ensured. The existence of the first rotational mating surface 222 and the second rotational mating surface 212 makes it possible to perform die pressing on the composite material blade 100 with a complex shape of the leading edge line 112 in the height direction.

[0069] It should be noted that in the mold closing state, the curve formed by the first rotational mating surface 222 and the second rotational mating surface 212 in the cross-section in the height direction is the mold closing line.

[0070] In this embodiment, since the mold closing point is set as the leading edge point, the intersection line of the first rotational mating surface 222 and the cavity 231 is the leading edge line 112 of the cavity 231. Correspondingly, the intersection line of the second rotational mating surface 212 and the cavity 231 is the leading edge line 112 of the cavity 231.

[0071] Figure 8 Fig. shows a mating structural schematic diagram of the first middle mold 224 and the second middle mold 214 of the composite material forming mold provided in this embodiment in the mold opening state. Figure 9 Fig. shows a mating structural schematic diagram of the first middle mold 224 and the second middle mold 214 of the composite material forming mold provided in this embodiment in the mold closing state. Please refer toFigures 1-9 In this embodiment, the back side die 220 of the blade includes a plurality of first sub-dies stacked along the height direction. The plurality of first sub-dies are fixed into an integral body by first fasteners 230, so that when the composite material blade 100 is compacted during mold closing, the relative positions between the plurality of first sub-dies are fixed and can rotate synchronously. First rotation mating surfaces 222 are provided on all the plurality of first sub-dies.

[0072] Similarly, the front side die 210 of the blade includes a plurality of second sub-dies stacked along the height direction. The plurality of second sub-dies are fixed into an integral body by second fasteners 219, so that when the composite material blade 100 is compacted during mold closing, the relative positions between the plurality of second sub-dies are fixed and can rotate synchronously. Second rotation mating surfaces 212 are provided on all the plurality of second sub-dies.

[0073] Specifically, in this embodiment, the first fasteners 230 and the second fasteners 219 can be bolts. It can be understood that in other embodiments, other fasteners can also be used to connect the plurality of first sub-dies and the plurality of second sub-dies. At the same time, other methods can also be used to connect the first sub-die and the second sub-die, such as welding.

[0074] Optionally, in this embodiment, the number of the first sub-dies is three, and the three first sub-dies are respectively a first upper die, a first middle die 224, and a first lower die 225. The number of the second sub-dies is also set to three, and the three second sub-dies are respectively a second upper die 213, a second middle die 214, and a second lower die 215. It can be understood that in other embodiments, the specific numbers of the first sub-dies and the second sub-dies can also be set according to requirements.

[0075] In this embodiment, the back side die 220 is provided with a rocker arm portion 226, the front side die 210 is provided with a first shaft hole section 216, and the rocker arm portion 226 is provided with a second shaft hole section 227. The first shaft hole section 216 and the second shaft hole section 227 communicate to form a mounting hole for mounting a pin shaft 234.

[0076] Specifically, as Figure 6 shown, in this embodiment, the rocker arm portion 226 is provided on the first middle die 224, the first shaft hole section 216 is opened on the second upper die 213, and at the same time, the front side die 210 further has a third shaft hole section 217 opened on the second lower die 215. The second middle die 214 has a groove for accommodating the rocker arm portion 226. When the back side die 220 and the front side die 210 are rotationally matched by the pin shaft 234, the rocker arm portion 226 extends into the groove of the second middle die 214, so that the second shaft hole section 227 on the rocker arm portion 226 can be coaxially distributed with the first shaft hole section 216 and the third shaft hole section 217, thereby forming a mounting hole.

[0077] It should be noted that in this embodiment, the rocker arm portion 226 is arranged in the middle of the airfoil back side mold 220 in the height direction. It can be understood that in some other embodiments, it can also be arranged on the upper and lower sides of the airfoil back side mold 220 in the height direction, or the number of rocker arm portions 226 can be specifically set according to the number of layers of the airfoil back side mold 220, as long as the arrangement positions of the rocker arm portions 226 on the airfoil back side mold 220 are symmetrical. Correspondingly, the number and positions of the shaft segment holes on the airfoil front side mold 210 can also be adjusted according to requirements.

[0078] Furthermore, one side of the rocker arm portion 226 close to the cavity 231 has a first mating plane, and the airfoil front side mold 210 has a second mating plane that mates with the first mating plane. In the closed mold state, there is a gap 229 between the first mating plane and the second mating plane.

[0079] Specifically, the first mating plane is arranged at the position where the rocker arm portion 226 is close to the first rotation mating surface 222. Correspondingly, the second mating plane is arranged at one end of the second rotation mating surface 212 far from the cavity 231. During the process of relative rotation between the airfoil back side mold 220 and the airfoil front side mold 210 for mold opening and closing switching, the first rotation mating surface 222 is always in contact with the second rotation mating surface 212. The first mating plane and the second mating plane are arranged at an angle, and the angle size changes as the rotation progresses. Since there is a gap 229 between the first mating plane and the second mating plane in the closed mold state, that is, during the mold opening and closing process, the first mating plane and the second mating plane are never in contact.

[0080] The airfoil back side mold 220 is provided with a first mold closing surface 228, and the airfoil front side mold 210 is provided with a second mold closing surface 218. The first mold closing surface 228 and the second mold closing surface 218 are located on one side of the tail end of the cavity 231. By setting the first mating plane and the second mating plane to have a gap 229 during mold closing, the first mating plane and the second mating plane will not affect the final mold closing positioning on one side of the tail end of the cavity 231.

[0081] Specifically, the first middle mold 224 is provided with a first convex block, and the first mold closing surface 228 is the side plane of the first convex block. The second middle mold 214 is provided with a second convex block, and the second mold closing surface 218 is the side surface of the second convex block. In the closed mold state, the first mold closing surface 228 is in contact with the second mold closing surface 218.

[0082] Further, the composite material blade forming die 200 further includes a die closing bolt 235. Connection holes 233 penetrating through the first die closing surface 228 and the second die closing surface 218 are formed on the first convex block and the second convex block. The die closing bolt 235 is installed in the connection holes 233 to connect and fix the first convex block and the second convex block, so that the first die closing surface 228 and the second die closing surface 218 are kept in a fitting state, and further, the composite material blade forming die 200 can be kept in a die closing state.

[0083] An embodiment of the present invention further provides a composite material blade forming method, which can be realized by the above-mentioned composite material blade forming die 200. Specifically, the composite material blade forming method includes:

[0084] S01: Press the blade basin side die 210 on the blade basin side of the blank to form the blade basin surface 114 through the first cavity surface 211 of the blade basin side die 210.

[0085] In this embodiment, since the composite material blade 100 has a hollow chamber 116, when pressing the blade basin surface 114 of the blank through the blade basin side die 210 to form the blade basin surface 114, the blank can be wrapped on the core mold 240, and then the core mold 240 is fixed by the support frame, so that the position of the blank is fixed. Then, the blade basin side die 210 is fixed in place, and the pressing of the blade basin side is realized through the combined action of the blade basin side die 210 and the core mold 240.

[0086] The blank is manufactured by composite material layup. In some other embodiments, before performing step S01, a step of preparing the blank may further be included. Specifically, for the blank of the blade structure as Figure 1 and Figure 2 shown, the following method may be adopted for preparation: The single-layer composite material is laid on the outside of the core mold 240 according to a certain rule, so as to form a blank roughly having the shape of the to-be-formed composite material blade 100.

[0087] S02: Rotationally connect the blade back side die 220 to the blade basin side die 210 through a pin shaft 234.

[0088] Insert the rocker arm part 226 of the blade back side die 220 into the groove of the blade basin side die 210, and then insert the pin shaft 234 from the first shaft hole section 216, and sequentially pass through the first shaft hole section 216, the second shaft hole section 227 and the third shaft hole section 217, so as to realize the rotational connection between the blade back side die 220 and the blade basin side die 210.

[0089] S03: Drive the blade back side die 220 to rotate relative to the blade basin side die 210 around the pin shaft 234.

[0090] Drive the mold 220 on the back side of the blade to rotate relative to the mold 210 on the front side of the blade around the pin shaft 234. During the rotation towards the mold-closed state, the mold 220 on the back side of the blade compacts the green body in sequence from the leading edge to the trailing edge 113 until the mold 220 on the back side of the blade is closed with the mold 210 on the front side of the blade. Finally, lock and fix the mold 220 on the back side of the blade and the mold 210 on the front side of the blade through the mold-closure bolts 235.

[0091] During the mold-closure process, since the composite material blade forming mold 200 is gradually closed from the leading edge to the trailing edge 113, defects such as wrinkles generated during the laying process on the green body are concentrated and driven to the trailing edge 113 during the closing process and finally enter the cavity 232. After the blade is molded by pressing and a laid blade with a flat leading edge is obtained, a part in the cavity 232 can be removed by machining to form the trailing edge 113 of the blade.

[0092] The composite material blade forming mold 200, device and method provided by the embodiments of the present invention, through the way of rotating and closing the mold around the pin shaft 234, gradually compresses the green body prepared by laying from front to back, reduces the risk of laying wrinkles at the leading edge of the blade and the nearby positions, makes the wrinkled positions concentrated at the trailing edge 113 with lower contour requirements, the wrinkled positions are more controllable, and improves the manufacturing accuracy of the blade and the aerodynamic efficiency of the blade. By forming the first rotating mating surface 222 and the second rotating mating surface 212 around the rotating shaft at the leading edge line 112 of the blade, the molding of the airfoil with a complex leading edge line 112 shape in the height direction can be realized, and the molding requirements of various airfoils are met. At the same time, through the reasonable setting of the axis position of the pin shaft 234, it is ensured that there is no path interference during the mold-closure process of the mold, and all the back surfaces 115 of the blade can be subjected to the mold pressure.

[0093] The above is only the specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any changes or substitutions that can be easily thought of by those skilled in the art within the technical scope disclosed by the present invention should be covered within the protection scope of the present invention.

Claims

1. A composite material blade forming mold is used for forming a composite material blade. The composite material blade has a suction side and a pressure side, and a leading edge is formed at the connection of one end of the suction side and the pressure side, and a trailing edge is formed at the connection of the other end. Characterized in that, The composite material blade forming mold includes: A suction side mold with a first cavity surface for forming at least part of the suction side of the blade. A pressure side mold with a second cavity surface for forming at least part of the pressure side of the blade; and A pin shaft that cooperates with both the suction side mold and the pressure side mold, enabling the suction side mold and the pressure side mold to rotate around the axis of the pin shaft, so that the composite material blade forming mold can switch between the open mold state and the closed mold state. Wherein, in the closed mold state, the first cavity surface and the second cavity surface enclose a cavity for forming the composite material blade. The cavity has a front end for forming the leading edge and a tail end for forming the trailing edge; the pin shaft is located on one side of the front end, so that during the process of switching from the open mold state to the closed mold state, the composite material blade is gradually compacted and formed in the direction from the leading edge to the trailing edge.

2. The composite material blade forming mold according to claim 1, Characterized in that, The suction side mold and the pressure side mold also form a cavity at the tail end in the closed mold state, and the cavity communicates with the cavity.

3. The composite material blade forming mold according to claim 1, Characterized in that, The pressure side mold has a first rotation mating surface, and the suction side mold has a second rotation mating surface; both the first rotation mating surface and the second rotation mating surface are arc surfaces arranged around the axis of the pin shaft, and during the process of switching to the closed mold state, the first rotation mating surface and the second rotation mating surface remain in contact.

4. The composite material blade forming mold according to claim 3, Characterized in that, The intersection line of the first rotation mating surface and the cavity is the leading edge line of the cavity; the intersection line of the second rotation mating surface and the cavity is the leading edge line of the cavity.

5. The composite material blade forming mold according to claim 1, Characterized in that, The pressure side mold is provided with a rocker arm part, the suction side mold is provided with a first shaft hole section, and the rocker arm part is provided with a second shaft hole section. The first shaft hole section and the second shaft hole section communicate to form a mounting hole for mounting the pin shaft.

6. The composite material blade forming mold according to claim 5, Characterized in that, One side of the rocker arm part close to the cavity has a first mating plane, and the suction side mold has a second mating plane that mates with the first mating plane. In the closed mold state, there is a gap between the first mating plane and the second mating plane.

7. The composite material blade forming mold according to claim 1, Characterized in that, The back-side mold of the blade includes a plurality of first sub-molds stacked in the height direction; the plurality of first sub-molds are fixed into an integral body by first fasteners.

8. The composite material blade forming mold according to claim 1, wherein, The front-side mold of the blade includes a plurality of second sub-molds stacked in the height direction; the plurality of second sub-molds are fixed into an integral body by second fasteners.

9. The composite material blade forming mold according to any one of claims 1-8, wherein, The position of the axis of the pin shaft satisfies the following conditions: On any height cross-section, the axis is located on the front side of the normal line passing through any point on the second cavity surface; the axis is located inside the tangent line of the mold closing point; wherein, the mold closing point is the contact point between the first cavity surface and the second cavity surface on the side close to the front end.

10. A composite material blade forming device, wherein, The composite material blade forming device includes a support frame and the composite material blade forming mold according to any one of claims 1-9, and the support frame is used to fix the front-side mold of the composite material forming mold.

11. A composite material blade forming method, wherein, The composite material blade forming method includes: Compacting the front-side mold on the front side of the blank to form the front surface of the blade through the first cavity surface of the front-side mold; Rotatably connecting the back-side mold to the front-side mold through a pin shaft; Driving the back-side mold to rotate relative to the front-side mold around the pin shaft, so that the second cavity surface of the back-side mold gradually compacts from the leading edge to the trailing edge of the blank until the back-side mold and the front-side mold are closed.

Images