Composite leaf spring body, mold for preparing leaf spring body and leaf spring assembly

Abstract

The present application provides a composite leaf spring body, a mold for preparing the leaf spring body, and a leaf spring assembly, wherein the leaf spring body has a parabolic structure, the concave parabola is the upper surface of the leaf spring body, the convex parabola is the lower surface of the leaf spring body, the surface adjacent to the upper surface and the lower surface is the side surface of the leaf spring body, the side surface extends inwardly in an area close to the upper surface to form a first inner chamfer, and / or the side surface extends inwardly in an area close to the lower surface to form a second inner chamfer. The leaf spring body provided by the present application can cut burrs or flash while ensuring the mechanical properties of the composite leaf spring.

Description

Technical Field

[0001] The invention relates to a suspension for an automobile, and more particularly to a composite leaf spring body, a mold for preparing the leaf spring body, and a leaf spring assembly. Background Art

[0002] With the increasing consumption of fossil energy and people's increasing attention to environmental issues, the innovation speed of new materials and technologies in the automotive industry is also increasing day by day. Lightweighting of automobiles can not only greatly reduce people's consumption of fossil energy, but also increase the cargo capacity of automobiles and increase the efficiency of automobile use. In addition to the characteristics of light weight and high strength, composite materials also have good shock absorption and fatigue life. Therefore, composite materials have been widely used in the automotive field.

[0003] Composite materials, as materials for automotive leaf springs, have been extensively researched by many automobile manufacturers in recent years and have also been commercially used in some car models.

[0004] In the related art, the forming process of composite leaf spring is generally divided into continuous filament winding (FilamentWinding) process and compression molding (Compressing Molding) process.

[0005] Most of the composite leaf springs developed by manufacturers adopt the molding process, which has higher precision than the fiber winding process. After the product is formed, the surface is smooth and no secondary processing is required. Resin transfer molding (RTM) is a typical molding process. Specifically, a preformed fiber-reinforced material is placed in the mold cavity. The mold must be sealed and tightened around the periphery, and the resin must flow smoothly inside. After the mold is closed, a certain amount of resin is injected, and the desired product can be demolded after the resin is solidified. However, for the molding process, burrs or flash will be formed on the side of the composite leaf spring during the process of sealing the mold. In this case, after the upper mold and the lower mold are separated, that is, after the product is demolded, the burrs or flash need to be removed by cutting. However, after cutting the burrs or flash, the continuity of the fiber filaments on the side of the composite leaf spring will be destroyed, and the broken fibers will be more likely to debond under stress, reducing the mechanical properties of the composite leaf spring.

[0006] Therefore, how to cut burrs or flash while ensuring the mechanical properties of composite leaf springs is a technical problem that urgently needs to be solved in this field. Summary of the invention

[0007] The present application provides a composite leaf spring body, a mold for preparing the leaf spring body, and a leaf spring assembly, which can cut burrs or flash while ensuring the mechanical properties of the composite leaf spring.

[0008] In the first aspect, the present application provides a composite leaf spring body, which has a parabolic structure, wherein the concave parabola is the top of the leaf spring body, the convex parabola is the bottom of the leaf spring body, the surfaces adjacent to the top and the bottom are the side surfaces of the leaf spring body, the side surfaces extend inwardly in an area near the top to form a first inner chamfer, and / or the side surfaces extend inwardly in an area near the bottom to form a second inner chamfer.

[0009] In the present embodiment, by setting the first inner chamfer and / or the second inner chamfer, even if burrs or flash are formed on the side of the leaf spring body with a relatively rectangular cross-section, the burrs or flash are formed in the middle area of ​​the side of the leaf spring body. Based on this, it is only necessary to cut off the burrs or flash formed in the middle area, thereby reducing the cutting area for the burrs or flash and reducing the probability of broken fibers. Furthermore, the possibility of debonding in the cutting area of ​​the leaf spring can be reduced and the mechanical properties of the leaf spring body can be improved.

[0010] In addition, by setting the first inner chamfer and / or the second inner chamfer, cutting of the side surface in the area close to the upper portion and the side surface in the area close to the lower portion is avoided, and it can be ensured that no broken fiber filaments appear in the area close to the upper portion and the side surface in the area close to the lower portion. When the leaf spring body is subjected to force, the edge area of ​​the leaf spring body (i.e., the area close to the upper portion and the area close to the lower portion of the side surface) is often the area where the force is most concentrated. In the present application, by setting the first inner chamfer and / or the second inner chamfer, the continuity of the fiber filaments in the edge area of ​​the leaf spring body (i.e., the area close to the upper portion and the area close to the lower portion of the side surface) can be ensured, thereby reducing the possibility of debonding in the edge area of ​​the leaf spring as much as possible and improving the mechanical properties of the leaf spring body.

[0011] In addition, when the leaf spring body is subjected to force, the area in the leaf spring body where the shape suddenly changes (i.e., the area where the first inner chamfer and / or the second inner chamfer is provided) is often the area where the force is most concentrated. In the present application, the structure formed by the side surface extending inwardly in the area near the upper side and the structure formed by the side surface extending inwardly in the area near the lower side are designed as inner chamfers, which can reduce the amplitude of the sudden change, thereby making the force distribution in the area in the leaf spring body where the shape suddenly changes (i.e., the area where the first inner chamfer and / or the second inner chamfer is provided) more uniform. In other words, the mechanical properties of the composite leaf spring body can be improved.

[0012] In short, the present application can cut burrs or flash while ensuring the mechanical properties of the composite leaf spring by setting the first inner chamfer and / or the second inner chamfer on the leaf spring body.

[0013] In some possible implementations, the side surface extends inwardly in an area near the upper portion to form a first inner chamfer, and / or the side surface extends inwardly in an area near the lower portion to form a second inner chamfer, and the side surface forms a raised mold seam between the first inner chamfer and the second inner chamfer, and the width of the mold seam is greater than the gap thickness between the upper mold and the lower mold, and the upper mold and the lower mold are used to prepare the leaf spring body, and the gap thickness is the thickness of the gap formed after the upper mold and the lower mold are tightened.

[0014] In the present embodiment, the width of the mold seam is designed to be larger than the gap thickness between the upper mold and the lower mold, so as to ensure that no burrs or flash appear on the edge area of ​​the leaf spring body (i.e., the area of ​​the side surface close to the upper surface and the area of ​​the side surface close to the lower surface). In other words, it can be ensured that the burrs or flash formed in the process of sealing the mold will only appear on the mold seam between the first inner chamfer and the second inner chamfer. Based on this, burrs or flash can be cut off while ensuring the mechanical properties of the composite leaf spring.

[0015] In some possible implementations, the width of the mold seam is greater than the thickness of the mold seam.

[0016] In some possible implementations, the mold seam is a trapezoidal structure.

[0017] Because when the leaf spring body is subjected to stress, the area where the shape of the leaf spring body suddenly changes (i.e., the area where the first inner chamfer and the second inner chamfer are provided) is often the area where the stress is most concentrated, the present application designs the mold seam as a trapezoidal structure, which can reduce the amplitude of the mutation, thereby making the stress distribution in the area where the shape of the leaf spring body suddenly changes (i.e., the area where the first inner chamfer and the second inner chamfer are provided) more uniform. In other words, the mechanical properties of the composite leaf spring body can be improved.

[0018] In some possible implementations, the side surface only extends inwardly in the area near the upper surface to form the first inner chamfer, and a mating surface of the leaf spring body is formed between the first inner chamfer and the area of ​​the side surface that does not extend inward, and the width of the mating surface is greater than the gap thickness between the upper mold and the lower mold. The upper mold and the lower mold are used to prepare the leaf spring body, and the gap thickness is the thickness of the gap formed between the upper mold and the lower mold after being tightened.

[0019] In the present embodiment, by designing the width of the mating surface to be larger than the gap thickness between the upper mold and the lower mold, it can be ensured that no burrs or flash appear on the edge areas of the leaf spring body (i.e., the area of ​​the side surface close to the upper surface and the area of ​​the side surface close to the lower surface). In other words, it can be ensured that the burrs or flash formed in the process of sealing the mold will only appear on the mating surface formed between the first inner chamfer and the area of ​​the side surface that does not extend inward. Based on this, burrs or flash can be cut off while ensuring the mechanical properties of the composite leaf spring.

[0020] In some possible implementations, the mold surface is inclined relative to the plane where the area that does not extend inwardly is located.

[0021] Because when the leaf spring body is subjected to force, the area where the shape of the leaf spring body suddenly changes (i.e., the area where the first inner chamfer is provided) is often the area where the force is most concentrated, the present application designs the mold surface to be inclined relative to the plane where the area that does not extend inward is located, which can reduce the amplitude of the mutation, and thereby make the force distribution in the area where the shape of the leaf spring body suddenly changes (i.e., the area where the first inner chamfer is provided) more uniform. In other words, the mechanical properties of the composite leaf spring body can be improved.

[0022] In some possible implementations, the first inner chamfer and the second inner chamfer are both R angles.

[0023] In some possible implementations, the value of the R angle is less than half of the first side length, the first side length is the side length of the side, and the first side length is perpendicular to the top or bottom.

[0024] Because when the leaf spring body is subjected to stress, the area where the shape of the leaf spring body suddenly changes (i.e., the area where the first inner chamfer and the second inner chamfer are provided) is often the area where the stress is most concentrated, the present application designs the value of the R angle to be less than half of the first side length, which can reduce the amplitude of the mutation as much as possible, thereby making the stress distribution in the area where the shape of the leaf spring body suddenly changes (i.e., the area where the first inner chamfer and the second inner chamfer are provided) more uniform. In other words, the mechanical properties of the composite leaf spring body can be improved.

[0025] In some possible implementations, the first inner chamfer and the second inner chamfer are both chamfered angles.

[0026] In some possible implementations, the chamfer angle ranges from 25 degrees to 65 degrees.

[0027] Because when the leaf spring body is subjected to force, the area where the shape of the leaf spring body suddenly changes (i.e., the area where the first inner chamfer and the second inner chamfer are provided) is often the area where the force is most concentrated, the present application designs the value of the chamfer angle to be in the range of 25 degrees to 65 degrees, which can reduce the amplitude of the mutation, and thereby make the force distribution in the area where the shape of the leaf spring body suddenly changes (i.e., the area where the first inner chamfer and the second inner chamfer are provided) more uniform. In other words, the mechanical properties of the composite leaf spring body can be improved.

[0028] In a second aspect, a mold for preparing a leaf spring body is provided, wherein a mold cavity is arranged inside the mold, and the shape of the mold cavity is the same as the shape of the leaf spring body described in the first aspect or any possible implementation of the first aspect.

[0029] In a third aspect, a leaf spring assembly is provided, comprising:

[0030] According to the leaf spring body described in the first aspect or any possible implementation of the first aspect, metal ears are fixedly provided at both ends of the leaf spring body, and the metal ears are fixedly connected to the frame. The middle part of the composite leaf spring body is fixed to the axle by a U-shaped bolt. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1 A schematic diagram of the installation of the leaf spring assembly provided for this application.

[0032] Figure 2 It is a schematic diagram of a composite leaf spring assembly provided in an embodiment of the present application.

[0033] Figure 3 and Figure 4 It is a schematic cross-sectional view of a leaf spring body provided with an R angle according to an embodiment of the present application.

[0034] Figure 5 and Figure 6 It is a schematic cross-sectional view of a leaf spring body provided with a chamfered angle provided in an embodiment of the present application. DETAILED DESCRIPTION

[0035] The technical solutions in the embodiments of the present application will be described below in conjunction with the accompanying drawings.

[0036] Leaf springs can be placed longitudinally or transversely on a car. The latter must be equipped with an additional guiding force transmission device to transmit longitudinal force, which makes the structure complex and increases the mass, so it is only used in a few light and micro cars. Longitudinal leaf springs can transmit various forces and moments, have a guiding function, and have a simple structure, so they are widely used in cars.

[0037] Figure 1 A schematic diagram of the installation of the leaf spring assembly provided for this application.

[0038] like Figure 1 As shown, the leaf spring assembly includes a steel leaf spring body 13, and two U-shaped bolts 14 are provided in the middle of the steel leaf spring body 13, which are used to fix the steel leaf spring body 13 to the axle 15. The front end of the steel leaf spring body 13 is fixed to the vehicle body 11 (frame) through the front ear 131 of the steel leaf spring body 13 and the front bracket 12; the rear end of the steel leaf spring body 13 is fixed to the vehicle body 11 (frame) through the rear ear 132 of the steel leaf spring body 13, the lifting ear 16 and the rear bracket 17.

[0039] Among them, the steel leaf spring body 13 can be composed of multiple steel plates. The width of a single steel plate body is unchanged, and the thickness has two types: constant cross-section and variable cross-section. The variable cross-section is divided into linear variable cross-section and parabolic variable cross-section. Since the stress at each point of the parabolic variable cross-section is equal, the variable cross-section leaf spring mostly adopts a parabolic variable cross-section.

[0040] With the development of science and technology, composite materials are gradually used in automobile suspension spring components. Composite materials have high specific strength and modulus, good fatigue resistance, damping and vibration reduction performance and corrosion resistance. Therefore, using composite materials as elastic components can greatly improve the smoothness and comfort of the vehicle, and the mass is only about 1 / 4 of the leaf spring. It not only effectively improves fuel efficiency, but also reduces the unsprung mass and unsprung vibration. At the same time, the service life is greatly improved. There is no need to replace the elastic components within the life of the vehicle, and the use and maintenance costs of the vehicle are relatively low.

[0041] The concept of composite materials refers to a material that cannot meet the use requirements and needs to be combined with two or more materials to form another material that can meet people's requirements, that is, composite materials. As an example, a single glass fiber, although it has high strength, is loose between fibers and can only withstand tension, but cannot withstand bending, shearing and compressive stress. It is also not easy to be made into a fixed geometric shape and is a soft body. If they are bonded together with synthetic resins, they can be made into various hard products with fixed shapes, which can withstand both tensile stress and bending, compression and shear stress, and can form glass fiber reinforced plastic-based composite materials. Because its strength is equivalent to that of steel and it contains glass components, it also has the same color, shape, corrosion resistance, electrical insulation, heat insulation and other properties as glass, so it can also be called "glass reinforced plastic".

[0042] There are many types of composite materials, which are generally composed of reinforcing materials and matrix materials. For example, reinforced concrete is also a composite material, where concrete is the matrix and steel bars are the reinforcing material.

[0043] Among them, the matrix material includes but is not limited to epoxy resin, polyester resin, thermoplastic resin, etc. For example, the matrix material can be a resin matrix, that is, the matrix of a resin-based composite material. The resin matrix refers to a glue system composed of a resin and a curing agent. As an example, the resin matrix may include a thermosetting resin and a thermoplastic resin. Thermosetting resins can only be heated and formed once, and solidify during the processing to form an infusible and insoluble network cross-linked polymer compound, so they cannot be regenerated. The resin matrix of the composite material is mainly thermosetting resin. Thermosetting resins include but are not limited to: phenolic resins, urea-formaldehyde resins, melamine-formaldehyde resins, epoxy resins, unsaturated resins, polyurethanes, polyimides, etc. Reinforcement materials include but are not limited to carbon fibers, glass fibers, aramid fibers, etc.

[0044] Reinforcement materials include, but are not limited to, carbon fiber, glass fiber, aramid fiber, etc. Reinforcement materials may be reinforced fibers, i.e., reinforcements of resin-based composite materials. As an example, according to geometric shapes, reinforcement materials include zero-dimensional granular, one-dimensional fibrous, two-dimensional sheet (e.g., cloth-like or felt-like) and three-dimensional solid structures. According to properties, there are inorganic reinforcement materials and organic reinforcement materials, which may be synthetic or natural. Inorganic reinforcement materials may be fibrous, such as inorganic glass fiber, carbon fiber, and a small amount of ceramic fibers such as silicon carbide, and organic reinforcement materials include aramid fibers (aramid), etc.

[0045] As an example, the reinforcing material of the composite leaf spring body involved in the present application can be glass fiber, carbon fiber, or a fiber bundle composed of glass fiber and carbon fiber, and its matrix material can be epoxy resin and other materials. It can also be called a fiber reinforced plastic (FRP) leaf spring body.

[0046] Compared with traditional metal materials, the biggest features of composite leaf springs are high specific strength, high specific modulus, good temperature resistance, good impact resistance, strong designability, more than 70% weight reduction, safe fracture, etc. Many foreign countries have used composite leaf springs on mass-produced vehicles, and many domestic and foreign automobile manufacturers are developing composite leaf springs. The installation of composite leaf springs is similar to that of steel leaf springs. Like steel leaf springs, the middle part needs to be fixed to the axle and the two ends need to be connected to the body. However, since it is difficult to make ears at both ends of the composite leaf spring, it is necessary to make components similar to ears.

[0047] Figure 2 It is a schematic diagram of a composite leaf spring assembly provided in an embodiment of the present application.

[0048] like Figure 2As shown, the composite leaf spring assembly 20 may include a composite leaf spring body 23, and the two ends of the composite leaf spring body 23 are respectively provided with ear-like components 231 and 232 to connect the two ends of the composite leaf spring body 23 to the vehicle body (frame); the middle part 24 of the composite leaf spring body 23 is to be fixed to the axle by a U-shaped bolt. As an example provided in the present application, the ear-like components 231 and 232 may be a frame articulation cylinder. Optionally, the ear-like components 231 and 232 may also include a leaf spring clamping plate, and the frame articulation cylinder is fixedly connected to the leaf spring clamping plate, for example, the leaf spring clamping plate may form a U-shaped structure with the frame articulation cylinder; optionally, the leaf spring clamping plate may be fixedly connected to a metal plate embedded in the composite leaf spring body 23, or may be fixedly connected to the composite leaf spring body 23 by a fastening bolt. Optionally, the U-shaped bolt may be fixedly connected to a metal plate embedded in the composite leaf spring body 23, or may be fixedly connected to the composite leaf spring body 23 by a fastening bolt.

[0049] The molding process of composite leaf springs is generally divided into continuous filament winding (Filament Winding) process and compression molding (Compressing Molding) process.

[0050] The molding process of composite leaf springs is generally divided into continuous filament winding (Filament Winding) process and compression molding (Compressing Molding) process.

[0051] Most of the composite leaf springs developed by manufacturers adopt the molding process, which has higher precision than the fiber winding process. After the product is formed, the surface is smooth and no secondary processing is required. Resin transfer molding (RTM) is a typical molding process. Specifically, a preformed fiber-reinforced material is placed in the mold cavity. The mold must be sealed and tightened around the periphery, and the resin must flow smoothly inside. After the mold is closed, a certain amount of resin is injected, and the desired product can be demolded after the resin is solidified. However, for the molding process, burrs or flash will be formed on the side of the composite leaf spring during the process of sealing the mold. In this case, after the upper mold and the lower mold are separated, that is, after the product is demolded, the burrs or flash need to be removed by cutting. However, after cutting the burrs or flash, the continuity of the fiber filaments on the side of the composite leaf spring will be destroyed, and the broken fibers will be more likely to debond under stress, reducing the mechanical properties of the composite leaf spring.

[0052] Based on this, the present application provides a composite leaf spring body, a mold for preparing the leaf spring body, and a leaf spring assembly, which can cut burrs or flash while ensuring the mechanical properties of the composite leaf spring.

[0053] In some embodiments, the leaf spring body has a parabolic structure, the concave parabola is the top of the leaf spring body, the convex parabola is the bottom of the leaf spring body, the surfaces adjacent to the top and the bottom are the side surfaces of the leaf spring body, the side surfaces extend inward in an area near the top to form a first inner chamfer, and / or the side surfaces extend inward in an area near the bottom to form a second inner chamfer.

[0054] In the present embodiment, by setting the first inner chamfer and / or the second inner chamfer, even if burrs or flash are formed on the side of the leaf spring body with a relatively rectangular cross-section, the burrs or flash are formed in the middle area of ​​the side of the leaf spring body. Based on this, it is only necessary to cut off the burrs or flash formed in the middle area, thereby reducing the cutting area for the burrs or flash and reducing the probability of broken fibers. Furthermore, the possibility of debonding in the cutting area of ​​the leaf spring can be reduced and the mechanical properties of the leaf spring body can be improved.

[0055] In addition, by setting the first inner chamfer and / or the second inner chamfer, cutting of the side surface in the area close to the upper portion and the side surface in the area close to the lower portion is avoided, and it can be ensured that no broken fiber filaments appear in the area close to the upper portion and the side surface in the area close to the lower portion. When the leaf spring body is subjected to force, the edge area of ​​the leaf spring body (i.e., the area close to the upper portion and the area close to the lower portion of the side surface) is often the area where the force is most concentrated. In the present application, by setting the first inner chamfer and / or the second inner chamfer, the continuity of the fiber filaments in the edge area of ​​the leaf spring body (i.e., the area close to the upper portion and the area close to the lower portion of the side surface) can be ensured, thereby reducing the possibility of debonding in the edge area of ​​the leaf spring as much as possible and improving the mechanical properties of the leaf spring body.

[0056] In addition, when the leaf spring body is subjected to force, the area in the leaf spring body where the shape suddenly changes (i.e., the area where the first inner chamfer and / or the second inner chamfer is provided) is often the area where the force is most concentrated. In the present application, the structure formed by the side surface extending inwardly in the area near the upper side and the structure formed by the side surface extending inwardly in the area near the lower side are designed as inner chamfers, which can reduce the amplitude of the sudden change, thereby making the force distribution in the area in the leaf spring body where the shape suddenly changes (i.e., the area where the first inner chamfer and the second inner chamfer are provided) more uniform. In other words, the mechanical properties of the composite leaf spring body can be improved.

[0057] In short, the present application can cut burrs or flash while ensuring the mechanical properties of the composite leaf spring by setting the first inner chamfer and / or the second inner chamfer on the leaf spring body.

[0058] It should be noted that chamfering refers to the processing of cutting the edges and corners of a workpiece into a certain inclined surface. Chamfering includes inner chamfering and outer chamfering. The outer chamfer is the chamfer formed by the part protruding outward, while the inner chamfer is the chamfer formed by the part of the figure or part recessed inward. The general purpose of chamfering is mainly to prevent the sharp angle formed during the processing of hard objects from causing damage to other objects or people. The chamfering of the hole can also facilitate the movement of the coupling in the hole. However, the role of the inner chamfer in the embodiment of the present application is mainly reflected in the following two aspects: first, it is used to reduce the cutting area for burrs or flash on the side of the leaf spring body to reduce the probability of broken fibers, thereby reducing the possibility of degumming in the cutting area of ​​the leaf spring and improving the mechanical properties of the leaf spring body; second, it is used to ensure the continuity of the fiber filaments in the edge area of ​​the leaf spring body (that is, the area of ​​the side close to the upper side and the area of ​​the side close to the lower side) to improve the mechanical properties of the leaf spring body.

[0059] The chamfers involved in the present application may be chamfers or rounded corners. For example, the chamfers may be 45-degree chamfers, which may also be referred to as C-angles. Rounded corners may also be referred to as R-angles, and the value of R-angles may be used to characterize the radius of the transition arc at the intersection of two straight lines, such as R3, R5, etc., which are transition arc radii of 3 and 5, respectively.

[0060] In some embodiments, the side surface extends inwardly in an area near the upper portion to form a first inner chamfer, and / or the side surface extends inwardly in an area near the lower portion to form a second inner chamfer, a convex mold seam is formed between the first inner chamfer and the second inner chamfer, a convex mold seam is formed between the first inner chamfer and the second inner chamfer, the width of the mold seam is greater than the gap thickness between the upper mold and the lower mold, the upper mold and the lower mold are used to prepare the leaf spring body, and the gap thickness is the thickness of the gap formed between the upper mold and the lower mold after being fastened. In one implementation, the width of the mold seam is greater than the thickness of the mold seam.

[0061] In the present embodiment, the width of the mold seam is designed to be larger than the gap thickness between the upper mold and the lower mold, so as to ensure that no burrs or flash appear on the edge area of ​​the leaf spring body (i.e., the area of ​​the side surface close to the upper surface and the area of ​​the side surface close to the lower surface). In other words, it can be ensured that the burrs or flash formed in the process of sealing the mold will only appear on the mold seam between the first inner chamfer and the second inner chamfer. Based on this, burrs or flash can be cut off while ensuring the mechanical properties of the composite leaf spring.

[0062] In one implementation, the mold seam is a trapezoidal structure. Optionally, the trapezoidal structure may be an isosceles trapezoidal structure.

[0063] Because when the leaf spring body is subjected to stress, the area where the shape of the leaf spring body suddenly changes (i.e., the area where the first inner chamfer and the second inner chamfer are provided) is often the area where the stress is most concentrated, the present application designs the mold seam as a trapezoidal structure, which can reduce the amplitude of the mutation, thereby making the stress distribution in the area where the shape of the leaf spring body suddenly changes (i.e., the area where the first inner chamfer and the second inner chamfer are provided) more uniform. In other words, the mechanical properties of the composite leaf spring body can be improved.

[0064] In some possible implementations, the side surface only extends inwardly in the area near the upper surface to form the first inner chamfer, and a mating surface of the leaf spring body is formed between the first inner chamfer and the area of ​​the side surface that does not extend inward, and the width of the mating surface is greater than the gap thickness between the upper mold and the lower mold. The upper mold and the lower mold are used to prepare the leaf spring body, and the gap thickness is the thickness of the gap formed between the upper mold and the lower mold after being tightened.

[0065] In the present embodiment, by designing the width of the mating surface to be larger than the gap thickness between the upper mold and the lower mold, it can be ensured that no burrs or flash appear on the edge areas of the leaf spring body (i.e., the area of ​​the side surface close to the upper surface and the area of ​​the side surface close to the lower surface). In other words, it can be ensured that the burrs or flash formed in the process of sealing the mold will only appear on the mating surface formed between the first inner chamfer and the area of ​​the side surface that does not extend inward. Based on this, burrs or flash can be cut off while ensuring the mechanical properties of the composite leaf spring.

[0066] In some implementations, the mold surface is inclined relative to a plane where the region that does not extend inwardly lies.

[0067] As an example, the first inner chamfer can be a chamfer, and the first inner chamfer extends to the area of ​​the side surface of the leaf spring body that does not extend inward. As another example, the die-matching surface is inclined relative to the plane where the area that does not extend inward is located, and the die-matching surface is formed between the first inner chamfer and the area that does not extend inward.

[0068] In the present embodiment, when the leaf spring body is subjected to stress, the region in the leaf spring body where the shape suddenly changes (i.e., the region where the first inner chamfer is provided) is often the region where the stress is most concentrated. The present application designs the mating surface to be inclined relative to the plane where the region that does not extend inward is located, thereby reducing the amplitude of the mutation and, thereby, making the stress distribution in the region in the leaf spring body where the shape suddenly changes (i.e., the region where the first inner chamfer is provided) more uniform. In other words, the mechanical properties of the composite leaf spring body can be improved.

[0069] In some embodiments, the first inner chamfer and the second inner chamfer are both R angles. In one implementation, the value of the R angle is less than half of the first side length, the first side length is the side length of the side, and the first side length is perpendicular to the top or bottom.

[0070] As an example, the length of the first side length is equal to the thickness of the leaf spring body. As another example, the length of the first side length is equal to the thickness of the mold gap.

[0071] Because when the leaf spring body is subjected to stress, the area where the shape of the leaf spring body suddenly changes (i.e., the area where the first inner chamfer and the second inner chamfer are provided) is often the area where the stress is most concentrated, the present application designs the value of the R angle to be less than half of the first side length, which can reduce the amplitude of the mutation as much as possible, thereby making the stress distribution in the area where the shape of the leaf spring body suddenly changes (i.e., the area where the first inner chamfer and the second inner chamfer are provided) more uniform. In other words, the mechanical properties of the composite leaf spring body can be improved.

[0072] Figure 3 and Figure 4 It is a schematic cross-sectional view of a leaf spring body 30 provided with an R angle according to an embodiment of the present application.

[0073] like Figure 3 As shown, the leaf spring body 30 includes an upper surface 31, a lower surface 32, and surfaces adjacent to the upper surface 31 and the lower surface 32 are the side surfaces of the leaf spring body 30, the side surfaces extend inwardly in a region near the upper surface 31 to form a first inner chamfer 331, and the side surfaces extend inwardly in a region near the lower surface 32 to form a second inner chamfer 332. Optionally, a raised mold seam 333 is formed between the first inner chamfer 331 and the second inner chamfer 332, and the upper surface or the lower surface of the mold seam 333 can be used to bear burrs or flash of the leaf spring body 30. Optionally, both the first inner chamfer 331 and the second inner chamfer 332 are R angles. Of course, as Figure 4 As shown, the leaf spring body 30 may also be designed with only one inner chamfer, namely, a first inner chamfer 331, and a mating surface 337 of the leaf spring body 30 is formed between the first inner chamfer 331 and the area 336 of the side that does not extend inward. The mating surface 337 of the leaf spring body 30 can be used to bear burrs or flash of the leaf spring body 30.

[0074] Of course, in other alternative embodiments, only one second inner chamfer 332 may be designed, and this application does not make any specific limitation to this.

[0075] In some embodiments, the first inner chamfer and the second inner chamfer are both chamfer angles. In one implementation, the chamfer angles range from 25 degrees to 65 degrees.

[0076] Because when the leaf spring body is subjected to stress, the area where the shape of the leaf spring body suddenly changes (i.e., the area where the first inner chamfer and / or the second inner chamfer is provided) is often the area where the stress is most concentrated, the present application designs the chamfer angle to be in the range of 25 to 65 degrees, which can minimize the amplitude of the mutation, thereby making the stress distribution in the area where the shape of the leaf spring body suddenly changes (i.e., the area where the first inner chamfer and / or the second inner chamfer is provided) more uniform. In other words, the mechanical properties of the composite leaf spring body can be improved.

[0077] Figure 5 and Figure 6 It is a schematic cross-sectional view of a leaf spring body 30 provided with a chamfered angle according to an embodiment of the present application.

[0078] like Figure 5 As shown, the leaf spring body 30 includes an upper surface 31, a lower surface 32, and surfaces adjacent to the upper surface 31 and the lower surface 32 are side surfaces of the leaf spring body 30, the side surface extends inwardly in a region near the upper surface 31 to form a first inner chamfer 334, and the side surface extends inwardly in a region near the lower surface 32 to form a second inner chamfer 335. Optionally, a raised mold seam 333 is formed between the first inner chamfer 334 and the second inner chamfer 335, and the upper surface or the lower surface of the mold seam 333 can be used to bear burrs or flash of the leaf spring body 30. Optionally, the first inner chamfer 334 and the second inner chamfer 335 are both chamfers. For example, the chamfer is a 45-degree chamfer. Of course, if Figure 6 As shown, the leaf spring body 30 may also be designed with only one inner chamfer, namely, a first inner chamfer 331, and a mating surface 337 of the leaf spring body 30 is formed between the first inner chamfer 331 and the area 336 of the side that does not extend inward. The mating surface 337 can be used to bear burrs or flash of the leaf spring body 30.

[0079] Of course, in other alternative embodiments, only one second inner chamfer 332 may be designed, and this application does not make any specific limitation to this.

[0080] The present application also provides a mold for preparing a leaf spring body, wherein a mold cavity is arranged inside the mold, and the shape of the mold cavity is the same as the shape of the leaf spring body described in the first aspect or any possible implementation of the first aspect.

[0081] The present application also provides a leaf spring assembly, including the leaf spring body described above, with metal ears fixedly provided at both ends of the leaf spring body, the metal ears are fixedly connected to the frame, and the middle part of the composite leaf spring body is fixed to the axle by a U-shaped bolt.

[0082] It should be understood that the leaf spring body, composite leaf spring, and composite leaf spring body described in the specification of the present invention can all be a resin-based fiber composite leaf spring body.

[0083] It should also be understood that the various specific embodiments provided in the present application are not limited to the above description. For example, under the specific teaching of the embodiments of the present application, those skilled in the art can also develop a structure in which the first inner chamfer and the second inner chamfer can be replaced with a step structure in the leaf spring body, or the mold seam can be designed as a step structure. Based on this, more specific embodiments can be obtained in combination with the adaptive design of the leaf spring body. Therefore, although the present application has been specifically shown and described with reference to the preferred embodiments, it should be understood that those skilled in the art can derive more technical solutions through changes in form and details, or any person skilled in the art who is familiar with the technical field can easily think of changes or replacements within the technical scope disclosed in the present application, which should be covered within the scope of protection of the present application.

Claims

1. A composite leaf spring body, the leaf spring body having a parabolic structure, the concave parabola being the upper surface of the leaf spring body, the convex parabola being the lower surface of the leaf spring body, the surface adjacent to the upper surface and the lower surface being the side surface of the leaf spring body, characterized in that: The side surface extends inwardly in a region close to the upper surface to form a first inner chamfer, and / or the side surface extends inwardly in a region close to the lower surface to form a second inner chamfer; Wherein, the middle area of ​​the side surface is used to bear the burrs or flash of the leaf spring body; The side surface extends inwardly in an area close to the upper surface to form the first inner chamfer, and the side surface extends inwardly in an area close to the lower surface to form the second inner chamfer. A convex mold seam is formed on the side surface between the first inner chamfer and the second inner chamfer, and the width of the mold seam is greater than the gap thickness between the upper mold and the lower mold. The upper mold and the lower mold are used to prepare the leaf spring body by a molding process, and the gap thickness is the thickness of the gap formed by the upper mold and the lower mold after being fastened; The burr or flash is formed in the process of sealing the mold, and the burr or flash is located on the mold seam so as to cut the burr or flash.

2. The leaf spring body according to claim 1, characterized in that: The width of the mold seam is greater than the thickness of the mold seam.

3. The leaf spring body according to claim 1, characterized in that: The mold seam is a trapezoidal structure.

4. A composite leaf spring body, the leaf spring body having a parabolic structure, the concave parabola being the upper surface of the leaf spring body, the convex parabola being the lower surface of the leaf spring body, the surface adjacent to the upper surface and the lower surface being the side surface of the leaf spring body, characterized in that: The side surface extends inwardly in a region close to the upper surface to form a first inner chamfer, and / or the side surface extends inwardly in a region close to the lower surface to form a second inner chamfer; Wherein, the middle area of ​​the side surface is used to bear the burrs or flash of the leaf spring body; The side surface extends inwardly only in a region close to the upper surface to form the first inner chamfer, a mating surface of the leaf spring body is formed between the first inner chamfer and a region of the side surface that does not extend inward, the width of the mating surface is greater than the gap thickness between the upper mold and the lower mold, the upper mold and the lower mold are used to prepare the leaf spring body, and the gap thickness is the thickness of the gap formed between the upper mold and the lower mold after being fastened; The burr or flash is formed in the process of sealing the mold, and the burr or flash is located on the mold surface so as to cut the burr or flash.

5. The leaf spring body according to claim 4, characterized in that: The mold joining surface is inclined relative to the plane where the area that does not extend inwardly is located.

6. The leaf spring body according to any one of claims 1 to 5, characterized in that: The first inner chamfer and the second inner chamfer are both R angles.

7. The leaf spring body according to claim 6, characterized in that: The value of the R angle is less than half of the first side length, the first side length is the side length of the side surface, and the first side length is perpendicular to the top or bottom surface.

8. The leaf spring body according to any one of claims 1 to 5, characterized in that: The first inner chamfer and the second inner chamfer are both chamfered angles.

9. The leaf spring body according to claim 8, characterized in that: The chamfer angle ranges from 25 degrees to 65 degrees.

10. A mold for preparing a leaf spring body, characterized in that: A cavity is provided inside the mold, and a shape of the cavity is the same as the shape of the leaf spring body according to any one of claims 1 to 9.

11. A leaf spring assembly, characterized in that: include: According to the leaf spring body according to any one of claims 1 to 9, metal ears are fixedly provided at both ends of the leaf spring body, the metal ears are fixedly connected to the frame, and the middle part of the leaf spring body is fixed to the axle by a U-shaped bolt.

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