Lightweight high-strength composite material connecting rod

Abstract

The invention discloses a composite material connecting rod structure, and relates to the technical field of composite material structure design and manufacturing, in particular to a light high-strength composite material connecting rod which comprises a composite material rod body, a flange connector, a flange clamp, an adjustable clamp and a tensile bolt set. The composite material rod body is made of fiber reinforced resin matrix composites through a winding or laying winding process, and reinforcing areas and transition oblique angles are arranged at the two ends of the composite material rod body. The adjustable clamp and the flange clamp are in interference fit with the end of the rod body through built-in inclination and surface texture, the flange connector is connected with the clamp through the tensile bolt set, and efficient transmission of tension and compression loads is achieved. Through the integrated combined structural design, the problems of stress concentration and interface failure caused by traditional glue joint or screw joint are solved, the bearing capacity, environmental adaptability and reliability of the connecting rod are remarkably improved, and the connecting rod is suitable for the high-load fields such as aerospace, high-speed rails and heavy machinery.

Description

Technical Field

[0001] This invention relates to the field of composite material structure design and manufacturing technology, specifically to a lightweight, high-strength composite material connecting rod. Background Technology

[0002] Currently, composite connecting rods are widely used in aerospace, high-speed rail, construction, and machinery. Composite connecting rods are typically made of fiber-reinforced resin matrix composites, capable of withstanding high tensile and compressive loads while maintaining a relatively light weight.

[0003] Due to the manufacturing difficulties of integral composite tie rods, composite connecting rods typically employ a separate design for the connecting joint and the rod system. The rod body can be fabricated using a winding process, while the joint is usually a metal structure, assembled into a connecting rod through screwing or adhesive bonding. However, because fiber-reinforced composites have relatively weak transverse strength, the metal end is prone to damaging the composite structure during screwing with the composite rod, making the connection point a weak link in the composite connecting rod. Adhesive-bonded connecting rods are susceptible to damage from adhesive quality and environmental factors, with the adhesive interface often failing before the rod itself, severely impacting the connecting rod's load-bearing capacity and safety. Under heavy load conditions, localized failure at the connection point is a significant challenge currently limiting the widespread application of fiber-reinforced composites in tension and compression rods.

[0004] Therefore, existing composite material connecting rods lack reliability under harsh environments such as heavy loads, humidity, and vibration, severely limiting their application in high-performance fields. There is an urgent need for a composite material connecting rod structure that is structurally sound, has high load-bearing capacity, and good environmental adaptability. Summary of the Invention

[0005] Purpose of the invention: The purpose of this invention is to overcome the shortcomings of the prior art and provide a lightweight, high-strength composite material connecting rod with high structural integration, strong load-bearing capacity, and good environmental adaptability, thereby solving the problem of easy failure of the connection parts of traditional composite material connecting rods.

[0006] Technical solution: A lightweight and high-strength composite material connecting rod, comprising: a composite material rod body (1), a flange joint (2), a flange clamp (3), an adjustable clamp (4), and a tensile bolt assembly (5);

[0007] The composite material rod (1) has a reinforcing zone and a transition angle at both ends; the adjustable clamp (4) is fitted onto the reinforcing zone at the end of the rod, and its inner wall has a slope that matches the transition angle of the rod; the flange clamp (3) is fitted onto the outside of the adjustable clamp (4), and its inner wall has a slope that matches the outer wall of the adjustable clamp; the flange joint (2) is connected to the flange clamp (3) through a tensile bolt group (5).

[0008] In a further embodiment, the composite rod (1) is made of a resin-based composite material reinforced with carbon fiber, glass fiber or aramid fiber, and is manufactured by dry or wet winding process, liquid molding or prepreg laying process.

[0009] In a further embodiment, the reinforcing regions at both ends of the composite rod (1) are formed by alternately laying a reference ply and a reinforcing ply, with the slope of the transition region being 3° to 5°.

[0010] In a further embodiment, the inner and outer surfaces of the adjustable clamp (4) and the flange clamp (3) are provided with textured structures to increase friction.

[0011] In a further embodiment, the adjustable clamp (4) is provided with a caliper hole for expanding the diameter during installation.

[0012] In a further embodiment, the flange joint (2) is one of a double-fork lug joint, a single-fork lug bearing joint, or a bearing rod combination joint.

[0013] In a further embodiment, the flange clamp (3) and the adjustable clamp (4) are made of aluminum alloy, titanium alloy or steel.

[0014] In a further embodiment, the tightening torque of the tensile bolt group (5) is 35-60 Nm, and it is locked by a locking pin.

[0015] The present invention has the following beneficial effects:

[0016] High degree of structural integration: The tight connection between the rod and the joint is achieved through the clamp angle fit and bolt preload, avoiding fiber breakage and stress concentration.

[0017] High load-bearing capacity: Tensile and compressive loads are transmitted through the clamp bevel and flange end face respectively, with a clear mechanical path and high load-bearing efficiency.

[0018] Good environmental adaptability: no adhesive interface, excellent resistance to moisture and heat and vibration.

[0019] Good manufacturability: The rod body can be produced using automated winding or lay-up processes, and the clamps and joints can be produced in a standardized manner, making it suitable for mass production.

[0020] High maintainability: Parts can be disassembled and replaced when necessary, extending service life. Attached Figure Description

[0021] Figure 1 This is a schematic diagram of the overall structure of the composite material connecting rod of the present invention;

[0022] Figure 2 This is a schematic diagram of the flange clamp structure;

[0023] Figure 3 This is a schematic diagram of a flange joint structure;

[0024] Figure 4 This is a schematic diagram of the adjustable clamp structure;

[0025] Figure 5 A schematic diagram of the composite material bar layup;

[0026] Figure 6 This is a schematic diagram of the clamp assembly installation;

[0027] Figure 7 This is a schematic diagram of the overall assembly of the connecting rod.

[0028] Figure reference numerals: 1. Composite material connecting rod; 2. Flange joint; 3. Flange clamp; 4. Adjustable clamp; 5. Tensile bolt assembly; 6. Caliper; 7. Tensile bolt hole; 8. Clamp slope; 9. Caliper hole. Detailed Implementation

[0029] The technical solution of the present invention will now be clearly and completely described with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0030] A lightweight, high-strength composite material connecting rod includes: a composite material connecting rod 1, a flange joint 2, a flange clamp 3, an adjustable clamp 4, and a tensile bolt assembly 5.

[0031] In one embodiment, such as Figures 1 to 7 As shown, the composite material connecting rod is manufactured by dry (wet) winding.

[0032] In one embodiment, such as Figures 1 to 7 As shown, the flange joint and flange clamp are provided with tensile bolt holes.

[0033] In one embodiment, such as Figures 1 to 7 As shown, flange joints, flange clamps, and adjustable clamps can be made of aluminum alloy, titanium alloy, or steel according to performance requirements;

[0034] In one embodiment, such as Figures 1 to 7 As shown, the connecting rod joint can be designed as a double-fork lug joint, a single-fork lug bearing joint, or a bearing rod combination joint as needed.

[0035] In one embodiment, such as Figures 1 to 7 As shown, the inner surface of the flange clamp is provided with a clamp slope of 3 to 5 degrees that matches the outer diameter of the adjustable clamp, and a suitable texture can be set as needed.

[0036] In one embodiment, such as Figures 1 to 7As shown, the adjustable clamp has a caliper hole, which is used with calipers for installation of the adjustable clamp with an enlarged diameter;

[0037] In one embodiment, such as Figures 1 to 7 As shown, the adjustable clamp inner diameter is set with a clamp slope of 3 to 5 degrees to match the transition area at the end of the composite material connecting rod.

[0038] In one embodiment, such as Figures 1 to 7 As shown, to increase the frictional force, the inner and outer surfaces of the adjustable clamp can be set with suitable textures to increase the frictional bonding force with the composite material connecting rod 1;

[0039] In one embodiment, such as Figures 1 to 7 As shown, composite material connecting rods can be wound with carbon fiber prepreg by liquid molding, robotic arms, or winding machines.

[0040] In one embodiment, such as Figures 1 to 7 As shown, the diameter, wall thickness, and reinforced zone dimensions of the composite material connecting rod are designed according to the tensile and compressive load-bearing requirements of the connecting rod.

[0041] In one embodiment, such as Figures 1 to 7 As shown, for composite connecting rods, a reference ply is first laid on the mandrel, and then reinforcing plies are laid on both ends during the laying of the remaining reference plies, with the reference plies and reinforcing plies laid alternately. A slope of 3–5° is used in the transition zone.

[0042] In one embodiment, the preparation process of the present invention is as follows:

[0043] Curing of composite material connecting rods and precision machining of the connecting rod ends;

[0044] The adjustable clamp is expanded by calipers, and the end reinforcement area of ​​the composite material connecting rod is fitted with the inner surface to match the slope of the end reinforcement area of ​​the composite material connecting rod.

[0045] Install flange clamps, fit adjustable clamps and composite connecting rods.

[0046] The flange joints and flange clamps at both ends are connected by tensile bolt assemblies.

[0047] The tightening torque of the tension bolt assembly can be set to 35–60 Nm according to the load requirements of the connecting rod, ensuring a tight fit between the inner diameter of the flange clamp and the end of the composite material connecting rod via the adjustable clamp. Simultaneously, the flange joint is tightly compacted against the end of the composite material connecting rod.

[0048] When the composite material connecting rod is under tension, the flange clamp is tightly engaged with the end of the composite material connecting rod through an adjustable clamp to transmit the connecting rod tension.

[0049] When the composite connecting rod is under pressure, the flange joint is tightly pressed against the end of the composite connecting rod to transmit the pressure.

[0050] After the tightening torque reaches the set range, use the anti-loosening safety pin to lock the tension nut to ensure that the flange joint and flange clamp cannot loosen during use, thus ensuring the integrity of the connecting rod assembly.

[0051] The linkage assembly is complete.

[0052] The assembly link is inspected, tested, packaged, and delivered.

[0053] In view of the above, this embodiment provides a composite material connecting rod for high-speed railway bogies.

[0054] Material preparation: The rod body is made of T700 carbon fiber / epoxy resin prepreg; the clamps and joints are made of 7075 aluminum alloy.

[0055] Rod preparation: Four base layers are first laid on the mandrel using a winding machine, and then two reinforcing layers are added at each end, alternating until the total thickness is 6mm, with a 5° slope in the transition zone. The curing conditions are 130℃ / 2h.

[0056] Processing clamps and joints: The inner wall of the flange clamp is machined with a 5° bevel; the inner and outer walls of the adjustable clamp are both machined with a 5° bevel and sandblasted to increase texture.

[0057] Assembly: Expand the diameter of the adjustable clamp with calipers and then fit it onto the end of the rod; put on the flange clamp; install the flange joint and insert the tensile bolt group; tighten the bolts to a torque of 45 Nm and install the anti-loosening pin.

[0058] Test: After static load testing, the tensile failure load of the connecting rod reached 180kN, and the compressive stability was good, meeting the requirements for high-speed rail use.

[0059] This invention proposes a lightweight and high-strength composite composite material connecting rod structure technology, which solves the technical problem of premature failure of the end connections in existing composite connecting rods, resulting in low load-bearing capacity of the composite connecting rods.

[0060] This invention proposes a composite fiber-reinforced composite material connecting rod scheme, characterized by its simple structure, ensuring continuous composite fiber, fully utilizing the material's advantages, light weight, and high load-bearing capacity; it is suitable for high-performance fiber-reinforced composite material connecting rods with heavy-duty requirements of tensile and compressive reciprocating loads.

[0061] This invention proposes a composite material connecting rod structure technology, which adopts a reliable combined structure and is particularly suitable for high-performance fiber-reinforced composite material connecting rods with requirements for humid and hot environments. It solves the problem of severely reduced bonding strength and reliability of metal joints in humid and hot environments.

[0062] This invention proposes a composite material combined connecting rod structure technology, which reduces the difficulty and cost of the manufacturing process, and enables high-performance fiber-reinforced composite material connecting rods to be mass-produced quickly and efficiently.

[0063] Obviously, the above embodiments are merely illustrative examples for clear explanation and are not intended to limit the implementation. Those skilled in the art will recognize that other variations or modifications can be made based on the above description. It is neither necessary nor possible to exhaustively list all possible implementations here. However, obvious variations or modifications derived therefrom are still within the scope of protection of this invention.

Claims

1. A lightweight, high-strength composite material connecting rod, characterized in that, include: Composite material rod (1), flange joint (2), flange clamp (3), adjustable clamp (4) and tensile bolt assembly (5); The composite material rod (1) has a reinforcing zone and a transition angle at both ends; the adjustable clamp (4) is fitted onto the reinforcing zone at the end of the rod, and its inner wall has a slope that matches the transition angle of the rod; the flange clamp (3) is fitted onto the outside of the adjustable clamp (4), and its inner wall has a slope that matches the outer wall of the adjustable clamp; the flange joint (2) is connected to the flange clamp (3) through a tensile bolt group (5).

2. The lightweight, high-strength composite material connecting rod according to claim 1, characterized in that, The composite rod (1) is made of resin-based composite material reinforced with carbon fiber, glass fiber or aramid fiber, and is manufactured by dry or wet winding process, braided liquid molding or prepreg laying process.

3. The lightweight, high-strength composite material connecting rod according to claim 1, characterized in that, The reinforced areas at both ends of the composite rod (1) are formed by alternately laying the reference ply and the reinforcing ply, and the slope of the transition area is 3° to 5°.

4. The lightweight, high-strength composite material connecting rod according to claim 1, characterized in that, The inner and outer surfaces of the adjustable clamp (4) and flange clamp (3) are provided with textured structures to increase friction.

5. A lightweight, high-strength composite material connecting rod according to claim 1, characterized in that, The adjustable clamp (4) is provided with a clamp hole for expanding the diameter during installation.

6. A lightweight, high-strength composite material connecting rod according to claim 1, characterized in that, The flange joint (2) is one of a double-fork lug joint, a single-fork lug bearing joint, or a bearing rod combination joint.

7. A lightweight, high-strength composite material connecting rod according to claim 1, characterized in that, The flange clamp (3) and adjustable clamp (4) are made of aluminum alloy, titanium alloy or steel.

8. A lightweight, high-strength composite material connecting rod according to claim 1, characterized in that, The tightening torque of the tensile bolt group (5) is 35-60 Nm, and it is locked by anti-loosening safety pins.

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