An electrical energy transmission joint and its preparation method

Abstract

The present invention discloses an electric energy transmission joint and a preparation method thereof. The electric energy transmission joint includes an electric energy transmission copper part, an electric energy transmission aluminum part and an aluminum wire. The electric energy transmission copper part includes a fixing part for connecting an electrical device and a connecting part for connecting the electric energy transmission aluminum part. A first through hole is provided inside the electric energy transmission aluminum part, and a second through hole is provided inside the connecting part. The aluminum conductor core exposed after the insulation layer is stripped from the front end of the aluminum wire extends into the cavity formed by connecting the first through hole and the second through hole, and the electric energy transmission aluminum part is connected to the aluminum wire by a crimping method. The electric energy transmission copper part is light in weight, fast in production, and saves production costs. Moreover, the automation of the loading and unloading of the electric energy transmission copper part and the electric energy transmission aluminum part can be realized, and the flash generated during welding can be directly cut off after welding, saving processing time and greatly improving the assembly efficiency.

Description

Technical Field

[0001] The present invention relates to the technical field of electrical connection, and in particular to an electric energy transmission joint and a preparation method thereof. Background Art

[0002] At present, under the premise of the overall lightweight of the wire harness, aluminum wires will be widely used. However, since most of the wiring terminals of electrical devices are still made of copper, the aluminum wires still need to be connected to the copper components for electric energy transmission. Generally, the copper components for electric energy transmission are solid, which is wasteful of materials. Moreover, the solid copper components for electric energy transmission are generally processed by hot forging, which consumes a high amount of energy, has a large processing error, and the manufacturing cost of the copper components for electric energy transmission is relatively high. In addition, when copper components for electric energy transmission with different shapes are connected to aluminum wires by welding, different tooling fixtures are required, which increases the cost and makes the management of tooling fixtures complex. Additionally, during welding, the aluminum wires are also welded in the welding equipment. Since the aluminum wires are relatively long and soft, it not only increases the equipment tooling cost, but also makes it difficult to achieve automatic loading and unloading. After welding, since the aluminum wires cannot rotate, the flash generated during welding cannot be removed.

[0003] Therefore, there is an urgent need in the technical field of electrical connection for an electric energy transmission joint that can further reduce the weight of copper terminals and the cost of aluminum wire harnesses. Summary of the Invention

[0004] In order to overcome the deficiencies of the prior art, the technical problem solved by the present invention is to provide an electric energy transmission joint, which uses a copper component for electric energy transmission with a through hole to connect with an aluminum component for electric energy transmission, further reducing the weight of the electric energy transmission joint and significantly reducing the manufacturing cost of the electric energy transmission joint.

[0005] The specific technical solution adopted by the present invention to solve the above technical problem is as follows:

[0006] An electric energy transmission joint includes a copper component for electric energy transmission, an aluminum component for electric energy transmission, and an aluminum wire. The copper component for electric energy transmission includes a fixing member for connecting an electrical device and a connecting member for connecting the aluminum component for electric energy transmission. A first through hole is provided inside the aluminum component for electric energy transmission, and a second through hole is provided inside the connecting member. The aluminum core exposed after stripping the insulating layer at the front end of the aluminum wire extends into the cavity formed by the connection of the first through hole and the second through hole, and the aluminum component for electric energy transmission is connected to the aluminum wire by crimping.

[0007] Further, the inner diameter of the aluminum component for electric energy transmission is 1 to 3 times the outer diameter of the circumscribed circle of the insulating layer of the aluminum wire.

[0008] Further, a sealing glue or solder is filled between the aluminum core and the cavity.

[0009] Furthermore, a transition connection device is provided between the aluminum conductor core and the inner wall of the cavity, and at least part of the surface of the transition connection device is provided with protrusions for piercing the oxide layers on the surfaces of the aluminum conductor core and the inner wall of the cavity.

[0010] Furthermore, the protrusions are in a corrugated structure, or a serrated structure, or a pit-like structure, or a spiky structure, or a barb-like structure, or a reticular structure.

[0011] Furthermore, the transition connection device is a hollow cylinder at least partially sleeved on the aluminum conductor core.

[0012] Further, the crimping length of the aluminum wire accounts for at least 5% of the length of the aluminum component for power transmission.

[0013] Further, the connecting piece and the aluminum component for power transmission are connected by welding.

[0014] Furthermore, the connecting piece and the aluminum component for power transmission are connected by friction welding.

[0015] Further, a copper-aluminum transition layer in which copper and aluminum atoms penetrate or combine with each other is formed between the connecting piece and the aluminum component for power transmission.

[0016] The present invention also discloses a preparation method for a power transmission joint, including the following steps:

[0017] Welding step: connecting the connecting piece of the copper component for power transmission and the aluminum component for power transmission together by welding;

[0018] Aluminum wire crimping step: inserting the aluminum conductor core exposed after stripping the insulating layer at the front end of the aluminum wire into the cavity, and then crimping the aluminum wire and the aluminum component for power transmission together.

[0019] Further, it further includes the step of filling a sealing glue or solder between the aluminum conductor core and the cavity.

[0020] Further, it further includes the step of providing a transition connection device on the aluminum conductor core.

[0021] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0022] 1. A second through hole is provided inside the connecting piece of the copper part for electric energy transmission, which significantly reduces the weight of the copper part for electric energy transmission, saves production costs, and the copper part for electric energy transmission can be stamped from copper pipe materials, with fast and simple production. Moreover, since the volumes of the copper part for electric energy transmission and the aluminum part for electric energy transmission are relatively small, automation of the loading and unloading of the copper part for electric energy transmission and the aluminum part for electric energy transmission can be achieved, and the flash generated during the welding of the connecting piece and the aluminum part for electric energy transmission can be directly removed after welding, saving processing time and greatly improving the assembly efficiency.

[0023] 2. Since the cavity formed by connecting the second through hole provided inside the connecting piece and the first through hole provided inside the aluminum part for electric energy transmission is filled with sealant or solder, on the one hand, the sealant or the solder expels the air in the cavity, avoiding the corrosion of the connecting piece and the aluminum part for electric energy transmission by air and water; on the other hand, since the material of the aluminum part for electric energy transmission is relatively soft, the mechanical properties of the electric energy transmission joint may be insufficient when crimping the aluminum wire, and the solder can connect the connecting piece, the aluminum part for electric energy transmission and the aluminum core together, strengthening the connection strength of the electric energy transmission joint to the aluminum wire. In addition, the solder increases the contact area between the aluminum core and the connecting piece and the aluminum part for electric energy transmission, further improving the electrical performance of the electric energy transmission joint.

[0024] 3. A transition connection device is further provided between the aluminum core and the inner wall of the cavity, and at least part of the surface of the transition connection device is provided with protrusions, and the protrusions are used to pierce the oxide layers on the surface of the aluminum core and the surface of the cavity, thereby reducing the resistance between the aluminum wire and the aluminum part for electric energy transmission through the protrusions, improving the conductivity of the crimping area between the aluminum wire and the aluminum part for electric energy transmission, and reducing the combustion accident caused by heat generated due to the increase in resistance in this crimping area.

[0025] 4. The crimping length of the aluminum wire accounts for at least 5% of the length of the aluminum part for electric energy transmission, further increasing the connection strength of the aluminum part for electric energy transmission and increasing the conductivity of the aluminum part for electric energy transmission.

[0026] 5. The inner diameter of the aluminum part for electric energy transmission is 1 to 3 times the outer diameter of the circumcircle of the insulation layer of the aluminum wire. This not only avoids the inability of the aluminum wire to be inserted into the aluminum part for electric energy transmission, but also ensures that the aluminum part for electric energy transmission and the aluminum wire will not rupture due to excessive deformation during crimping.

[0027] 6. The transition connection device is a hollow cylinder that at least partially sleeves on the aluminum conductor core. On the one hand, the large-scale automated production of the installation of the transition connection device improves production efficiency; on the other hand, the transition connection device can pre-shrink the loose aluminum conductor core, making it more convenient for the aluminum conductor core to be inserted into the cavity, avoiding the situation where some of the core wires of the aluminum conductor core are outside the cavity during the production process, and improving the product quality of the power transmission joint.

[0028] 7. A copper-aluminum transition layer formed by the mutual penetration or combination of copper and aluminum atoms is formed between the connecting piece and the aluminum power transmission part. The copper-aluminum transition layer can effectively reduce the electrochemical corrosion between copper and aluminum, extending the service life of the power transmission joint by about 20%; moreover, the connecting piece and the aluminum power transmission part are connected by friction welding, which can improve production efficiency by about 26%, reduce the number of workers, avoid misoperations caused by personnel fatigue, reduce safety accidents, and improve product quality.

[0029] The above description is only an overview of the technical solution of the present invention. In order to be able to more clearly understand the technical means of the present invention, it can be implemented according to the content of the specification. And in order to make the above and other purposes, features and advantages of the present invention more obvious and understandable, the following specific preferred embodiments are given, and in conjunction with the accompanying drawings, the details are described as follows. Brief Description of the Drawings

[0030] Figure 1 It is a schematic structural diagram of the power transmission joint described in the present invention;

[0031] Among them, Figure 1 The reference numerals are:

[0032] 1. Fixing piece; 2. Connecting piece; 3. Aluminum wire; 4. Aluminum conductor core; 5. Insulating layer; 6. Copper-aluminum transition layer; 7. Sealant or solder; 8. Transition connection device; 9. Aluminum power transmission part. Detailed Embodiment

[0033] To further elaborate on the technical means and effects adopted by the present invention to achieve the intended invention purpose, the following combines the accompanying drawings and preferred embodiments to detail the specific implementation manner, structure, features and effects according to the present invention as follows:

[0034] Such as Figure 1, the present invention discloses an electric energy transmission joint, which includes an electric energy transmission copper part, an electric energy transmission aluminum part 9 and an aluminum wire 3. The electric energy transmission copper part includes a fixing part 1 for connecting an electrical device and a connecting part 2 for connecting the electric energy transmission aluminum part 9. A second through hole is provided inside the connecting part 2, and a first through hole is provided inside the electric energy transmission aluminum part 9. After the insulation layer 5 is stripped from the front end of the aluminum wire 3, it extends into the cavity formed by connecting the first through hole and the second through hole, and the electric energy transmission aluminum part 9 is connected to the aluminum wire 3 by crimping.

[0035] Since a second through hole is provided inside the connecting part 2, the weight of the electric energy transmission copper part is greatly reduced, and the production cost is saved. Moreover, when the electric energy transmission joint is connected, first, the connecting part 2 of the electric energy transmission copper part is connected to the electric energy transmission aluminum part 9, then the insulation layer 5 is stripped from the front end of the aluminum wire 3 and it extends into the cavity formed by connecting the first through hole and the second through hole, and finally the electric energy transmission aluminum part 9 and the aluminum wire 3 are crimped. Its connection method is simple, the automation of the assembly of the electric energy transmission joint can be realized, and the assembly efficiency is greatly improved.

[0036] Moreover, since the volumes of the electric energy transmission copper part and the electric energy transmission aluminum part 9 are relatively small, the automation of the loading and unloading of the electric energy transmission copper part and the electric energy transmission aluminum part 9 can be realized. Moreover, the flash generated during the welding of the connecting part 2 and the electric energy transmission aluminum part 9 can be directly removed after welding, so that the electric energy transmission joint does not carry the aluminum wire 3 when removing the flash. This not only saves processing time and improves the assembly efficiency, but also can avoid the influence on the electric energy transmission joint when removing the flash with the aluminum wire 3, and improves the yield of the electric energy transmission joint.

[0037] It should be noted that in the present invention, the electric energy transmission copper part is formed by stamping a tubular copper pipe, and the formed electric energy transmission copper part includes a fixing part 1 and a connecting part 2, and a second through hole is provided inside the connecting part 2. Moreover, the position where the front end of the aluminum wire 3 extends into the cavity can be inside the first through hole or inside the second through hole.

[0038] Since copper is an active metal, the electric energy transmission copper part is prone to oxidation corrosion during use, which increases the resistance of the electric energy transmission copper part and may cause a combustion accident in severe cases. Therefore, in order to extend the service life of the electric energy transmission copper part, a coating is provided on the surfaces of the fixing part 1 and the connecting part 2, and the material of the coating contains at least one of nickel, cadmium, zirconium, chromium, cobalt, manganese, aluminum, tin, titanium, zinc, copper, silver or gold, so as to reduce the oxidation corrosion rate of the electric energy transmission copper part through the coating and extend the service life of the electric energy transmission copper part.

[0039] As a preferred solution, the inner diameter of the aluminum part 9 for power transmission is 1 to 3 times the diameter of the circumscribed circle of the aluminum wire insulation layer 5. On the one hand, it is convenient for the front end of the aluminum wire 3 to extend into the cavity formed by connecting the first through hole and the second through hole after stripping the insulation layer 5. On the other hand, since the aluminum part 9 for power transmission is connected to the aluminum wire 3 by crimping, if the inner diameter of the aluminum part 9 for power transmission is more than 3 times the diameter of the circumscribed circle of the aluminum wire insulation layer 5, the aluminum part 9 for power transmission needs to be compressed by a large proportion to ensure crimping to the aluminum wire 3, which easily causes the aluminum part 9 for power transmission to crack.

[0040] To verify the influence of the ratio of the inner diameter of the aluminum part for power transmission to the diameter of the circumscribed circle of the aluminum wire insulation layer 5 on the pulling force and voltage drop of the power transmission joint, the pulling force and voltage drop of the power transmission joints made with different ratios of the inner diameter of the aluminum part 9 for power transmission to the diameter of the circumscribed circle of the aluminum wire insulation layer 5 were investigated. The experimental results are shown in Table 1:

[0041] Table 1: Influence of the ratio of the inner diameter of the aluminum part for power transmission to the diameter of the circumscribed circle of the aluminum wire insulation layer on the performance of the power transmission joint

[0042]

[0043] According to Table 1, when the ratio of the inner diameter of the aluminum part 9 for power transmission to the diameter of the circumscribed circle of the aluminum wire insulation layer 5 is less than 1, the aluminum wire 3 cannot be inserted into the interior of the aluminum part for power transmission. When the ratio of the inner diameter of the aluminum part 9 for power transmission to the diameter of the circumscribed circle of the aluminum wire insulation layer 5 is greater than 3, the pulling force of the power transmission joint is lower than the standard value of 2000 N, and the voltage drop of the power transmission joint is higher than the standard value of 0.5 mV, which no longer meets the requirements of the mechanical and electrical properties of the power transmission joint. Moreover, when the ratio of the inner diameter of the aluminum part 9 for power transmission to the diameter of the circumscribed circle of the aluminum wire insulation layer 5 is relatively large, the aluminum part 9 for power transmission needs to be compressed by a large proportion to ensure crimping to the aluminum wire 3, which easily causes the aluminum part 9 for power transmission to crack.

[0044] After the insulating layer 5 of the front end of the aluminum wire 3 is stripped off, a sealing glue or solder 7 is filled between the exposed aluminum core 4 and the cavity. On the one hand, the sealing glue or solder 7 discharges the air in the cavity, avoiding the corrosion of the air and water in the cavity to the connector 2 and the electric energy transmission aluminum part 9. On the other hand, since the material of the electric energy transmission aluminum part 9 is relatively soft, when it crimps the aluminum wire 3, it may cause insufficient mechanical properties of the electric energy transmission joint, while the sealing glue or solder 7 connects the connector 2, the electric energy transmission aluminum part 9 and the aluminum core 4 together, strengthening the connection strength of the electric energy transmission joint to the aluminum wire 3. In addition, the solder 7 increases the contact area between the aluminum core 4 and the connector 2 and the electric energy transmission aluminum part 9, further improving the electrical performance of the electric energy transmission joint.

[0045] It should be noted that in the present invention, the material of the solder contains at least one of nickel and nickel alloy, cadmium and cadmium alloy, zirconium and zirconium alloy, chromium and chromium alloy, cobalt and cobalt alloy, manganese and manganese alloy, tin and tin alloy, titanium and titanium alloy, zinc and zinc alloy, copper and copper alloy, silver and silver alloy or gold and gold alloy. As a preferred method, the material of the solder is a metal or alloy with a melting point not higher than that of aluminum.

[0046] Moreover, since the sealing glue 7 has good ductility and sealing performance, when the sealing glue 7 is filled between the aluminum core 4 and the cavity, the sealing glue 7 can seal and protect the area between the aluminum core 4 and the cavity, so that the aluminum core 4 and the cavity are greatly reduced from being eroded by moisture and salt spray, thereby prolonging the service life of the electric energy transmission joint.

[0047] The sealing glue 7 includes but is not limited to conductive glue, rubber sealing glue, resin sealing glue or oil sealing glue.

[0048] In order to understand the influence of the sealing glue or solder on the performance of the electric energy transmission joint, the inventor conducted Experiment 2, and the experimental results are shown in Table 2:

[0049] Table 2 Influence of Sealing Glue or Solder on the Performance of the Electric Energy Transmission Joint

[0050]

[0051]

[0052] As can be seen from the above table: when sealant or solder is filled between the aluminum conductor core 4 and the cavity, the pulling force value of the power transmission joint is significantly greater than that of the power transmission joint when there is no sealant or solder filled between the aluminum conductor core 4 and the cavity, while the voltage drop value is less than that of the power transmission joint when there is no sealant or solder filled between the aluminum conductor core 4 and the cavity. Therefore, when sealant or solder is filled between the aluminum conductor core 4 and the cavity, the power transmission joint has better electrical and mechanical properties.

[0053] As a further preferred solution, a transition connection device 8 is further provided between the aluminum conductor core 4 and the inner wall of the cavity, and at least part of the surface of the transition connection device 8 is provided with protrusions, and the protrusions are used to pierce the oxide layers on the surfaces of the aluminum conductor core 4 and the inner wall of the cavity.

[0054] It should be noted that in the present invention, the material of the transition connection device 8 contains at least one of nickel and nickel alloys, cadmium and cadmium alloys, zirconium and zirconium alloys, chromium and chromium alloys, cobalt and cobalt alloys, manganese and manganese alloys, tin and tin alloys, titanium and titanium alloys, zinc and zinc alloys, copper and copper alloys, silver and silver alloys, or gold and gold alloys.

[0055] On the one hand, the protrusions increase the contact area between the aluminum conductor core 4, the transition connection device 8, and the power transmission aluminum part 9, and increase the friction between the aluminum wire 3 and the transition connection device 8, and between the transition connection device 8 and the power transmission aluminum part 9, so as to prevent the aluminum wire 3 from detaching from the power transmission aluminum part 9, making the power transmission joint have better mechanical properties.

[0056] On the other hand, the protrusions also increase the conductive bumps of the aluminum conductor core 4, enhance the conductive effect, and at the same time, they will also break the oxide layers on the surfaces of the aluminum conductor core 4 and the inner wall of the cavity, so that the aluminum conductor core 4 is in direct contact with the transition connection device 8 and the conductive part of the transition connection device 8 and the cavity, improving the electrical performance of the power transmission joint.

[0057] Specifically, the protrusions are in a corrugated structure, a serrated structure, a pit-shaped structure, a spiked structure, a reverse tooth-shaped structure, or a mesh structure, so as to not only increase the surface area of the transition connection device 8, but also enhance the connection between the transition connection device 8 and the power transmission aluminum part 9 through the protrusions, break more oxide layers, and improve the conductivity.

[0058] In order to understand the influence of the protrusions on the performance of the power transmission joint, the inventor takes the protrusions in the corrugated structure, serrated structure, pit-shaped structure, spiked structure, reverse tooth-shaped structure, and mesh structure as examples to prove the influence of the protrusions on the performance of the power transmission joint, and the results are shown in Table 3:

[0059] Table 3 Influence of the protrusion on the performance of the power transmission joint

[0060]

[0061]

[0062] As can be seen from the above table, when at least part of the surface of the transition connection device 8 is provided with protrusions of the above shape structure, the pulling force of the power transmission joint is greater than that of the power transmission joint when there are no protrusions on the surface of the transition connection device 8, while the voltage drop value is less than the voltage drop of the power transmission joint when there are no protrusions on the surface of the transition connection device 8. Therefore, when at least part of the surface of the transition connection device 8 is provided with protrusions, the power transmission joint has better mechanical properties and electrical properties.

[0063] In other embodiments, the transition connection device 8 is a hollow cylinder at least partially sleeved on the aluminum conductor core 4. When the transition connection device 8 is a hollow cylinder, on the one hand, it can realize automated production with high production efficiency; on the other hand, the loose aluminum conductor core 4 can be pre-shrunk through the transition connection device 8, so that the aluminum conductor core 4 can be more conveniently inserted into the cavity to avoid the situation that some of the core wires of the aluminum conductor core 4 cannot be inserted into the interior of the cavity during the production process, which facilitates the production and processing of the power transmission joint.

[0064] In order to ensure better crimping effect after the power transmission aluminum part 9 and the aluminum wire 3 are crimped, the crimping length of the aluminum wire 3 accounts for at least 5% of the length of the power transmission aluminum part 9. This is because if the crimping length of the aluminum wire 3 is too short, the fixing force of the power transmission aluminum part 9 on the aluminum wire 3 is insufficient, which may cause the aluminum wire 3 to easily break away from the power transmission aluminum part 9; moreover, if the crimping length is too short, the contact area at the crimping part of the aluminum wire 3 and the power transmission aluminum part 9 will become smaller, the current conduction area is relatively small, the resistance between the aluminum wire 3 and the power transmission aluminum part 9 increases, the crimping part gets hot, and the electrical properties of the power transmission joint are reduced, and in severe cases, it may cause a combustion accident.

[0065] In order to understand the influence of the proportion of the crimping length of the aluminum wire 3 to the length of the power transmission aluminum part 9 on the performance of the power transmission joint, the inventor investigated the proportion of the crimping length of different aluminum wires 3 to the length of the power transmission aluminum part 9, and then tested the mechanical properties and electrical properties of the above power transmission joint. The specific test results are shown in Table 4:

[0066] Table 4 Influence of the proportion of the crimping length of the aluminum wire to the length of the power transmission aluminum part on the performance of the power transmission joint

[0067]

[0068]

[0069] As can be seen from the above table, when the proportion of the crimping length of the aluminum wire 3 in the length of the aluminum component 9 for power transmission is less than 5%, the pulling force of the power transmission joint is less than 2000 N, which does not meet the requirements of the mechanical properties of the aluminum joint, and the voltage drop is greater than 0.5 mV, which does not meet the electrical performance requirements, seriously affecting the service life of the power transmission joint. Therefore, preferably, the crimping length of the aluminum wire 3 accounts for at least 5% of the length of the aluminum component 9 for power transmission.

[0070] As a further preferred solution, the connecting member 2 and the aluminum component 9 for power transmission are connected by welding.

[0071] It should be noted that: welding includes methods such as friction welding, resistance welding, ultrasonic welding, electromagnetic welding, pressure diffusion welding, arc welding, etc. Among them:

[0072] (1) Friction welding is carried out by using a friction welding device, which rotates the first workpiece and applies pressure to the rotating first workpiece by the second workpiece. Heat is generated by friction, and the first workpiece and the second workpiece are welded together by relying on the pressure. Its advantages are fast welding speed and no pollution such as noise, smoke, and strong light.

[0073] (2) Resistance welding is a method of locally heating the weldment by using the resistance heat generated by the current passing through the weldment and the contact point, and at the same time applying pressure for welding. Its advantages are that no filler metal is required, the productivity is high, the deformation of the weldment is small, and it is easy to realize automation.

[0074] (3) Ultrasonic welding is to transfer high-frequency vibration waves to the surfaces of two objects to be welded. Under pressure, the surfaces of the two objects rub against each other to form a fusion between molecular layers. Its advantages are short welding time, no need for any flux, gas, or solder, no welding sparks, and environmental protection and safety.

[0075] (4) Electromagnetic welding is to use an instantaneous current to generate a strong magnetic field, so that the weldments are welded together under the action of the magnetic field force. Its advantages are non-contact welding, fast welding speed, small internal stress in welding, and high processing accuracy.

[0076] (5) Pressure diffusion welding is a welding method that presses two weldments tightly together, and through heating and heat preservation, the weldments reach atomic mutual diffusion to form a metallurgical connection. Its advantages are that the weldments do not overheat or melt, the quality of the welded joint is high, large-area weldments can be welded, the welding accuracy of the weldments is high, and the deformation is small.

[0077] (6) Arc welding uses an electric arc as the heat source, utilizes the physical phenomenon of air discharge, converts electrical energy into the heat and mechanical energy required for welding, and thus achieves the purpose of connecting metals. Its advantages are that it is not restricted by the welding environment and is applicable to the welding of various metal materials, various thicknesses, and various structural shapes. If precision welding is required, plasma welding can also be used. Plasma welding belongs to a type of arc welding, but the plasma arc has concentrated energy, high productivity, fast welding speed, small stress deformation, and a more stable arc.

[0078] As a further preferred method, the connecting member 2 and the electric energy transmission aluminum member 9 are connected by friction welding. This is because for butt parts with a large cross-sectional area having through holes, the method of friction welding is simpler.

[0079] As a further preferred solution, a copper-aluminum transition layer 6 is formed between the connecting member 2 and the electric energy transmission aluminum member 9 by the mutual penetration or combination of copper and aluminum atoms. And the copper-aluminum transition layer 6 at least contains a mixture of copper and aluminum simple substances or a mixture of copper and aluminum simple substances and copper-aluminum solid solution. Moreover, through the copper-aluminum transition layer 6, the electrochemical corrosion between copper and aluminum can be slowed down, and the service life of the electric energy transmission joint can be extended.

[0080] The present invention also discloses a preparation method of an electric energy transmission joint, including the following steps,

[0081] Welding step: Connect the connecting member 2 of the electric energy transmission copper member and the electric energy transmission aluminum member 9 together by welding;

[0082] Aluminum wire 3 crimping step: After stripping the insulating layer 5 at the front end of the aluminum wire 3 to expose the aluminum core 4, insert the aluminum core 4 into the cavity, and then crimp the aluminum wire 3 and the electric energy transmission aluminum member 9 together.

[0083] Further, between the welding step and the aluminum wire 3 crimping step, there is also a step of filling a sealing glue or solder 7 between the aluminum core 4 and the cavity.

[0084] Specifically, filling the sealing glue or solder 7 into the cavity is: Through the holes on the surface of the electric energy transmission copper member, pour the molten sealing glue or solder 7 into the interior of the welded electric energy transmission copper member and the electric energy transmission aluminum member 9.

[0085] Further preferably, between the step of filling the sealing glue or solder 7 into the cavity and the aluminum wire 3 crimping step, there is also a step of sleeving a transition connection device 8 on the aluminum core 4.

[0086] It should be noted that in the description of the present invention, terms such as "first", "second", etc. are only used to describe the names of each component, and cannot be understood as indicating or implying the relative importance of each component.

[0087] The above embodiments are only preferred embodiments of the present invention, and cannot be used to limit the scope of protection of the present invention. Any non-substantive changes and substitutions made by those skilled in the art based on the present invention fall within the scope of protection required by the present invention.

Claims

1. A power transmission joint, comprising a power transmission copper part, a power transmission aluminum part and an aluminum wire. The power transmission copper part includes a fixing part for connecting an electrical device and a connecting part for connecting the power transmission aluminum part, and is characterized in that: A first through hole is provided inside the aluminum component for electric energy transmission, and a second through hole is provided inside the connecting component. The aluminum conductor core exposed after stripping the insulating layer at the front end of the aluminum wire extends into the cavity formed by connecting the first through hole and the second through hole, and the aluminum component for electric energy transmission is connected to the aluminum wire by means of crimping; a sealant or solder is filled between the aluminum conductor core and the cavity, and the sealant or solder is located between the front end of the aluminum conductor core and the bottom wall of the second through hole; a transition connection device is further provided between the aluminum conductor core and the inner wall of the cavity, and at least part of the surface of the transition connection device is provided with protrusions, and the protrusions are used for piercing the oxide layers on the surface of the aluminum conductor core and the inner wall surface of the cavity; the protrusions are in a corrugated structure or a serrated structure or a pit-shaped structure or a spiked structure or a reverse tooth-shaped structure or a mesh structure.

2. The electrical energy transmission joint according to claim 1, wherein: The inner diameter of the aluminum component for electric energy transmission is 1 to 3 times the outer diameter of the circumcircle of the insulating layer of the aluminum wire.

3. The electrical energy transmission joint according to claim 1, characterized in that: The transition connection device is a hollow cylinder that is at least partially sleeved on the aluminum conductor core.

4. The electrical energy transmission joint according to claim 1, wherein: The crimping length of the aluminum wire accounts for at least 5% of the length of the aluminum component for electric energy transmission.

5. The electrical energy transmission connector according to claim 1, characterized in that: The connecting component and the aluminum component for electric energy transmission are connected by means of welding.

6. The electrical energy transmission joint according to claim 5, wherein: The connecting component and the aluminum component for electric energy transmission are connected by means of friction welding.

7. The electrical energy transmission joint according to claim 5, wherein: A copper-aluminum transition layer in which copper and aluminum atoms penetrate or combine with each other is formed between the connecting component and the aluminum component for electric energy transmission.

8. A method for preparing an electrical energy transmission joint according to any one of claims 1-7, characterized in that: It includes the following steps Welding step: Connect the connecting component of the copper component for electric energy transmission and the aluminum component for electric energy transmission together by means of welding; Aluminum wire crimping step: The aluminum conductor core exposed after stripping the insulating layer at the front end of the aluminum wire extends into the cavity, and then the aluminum wire and the aluminum component for electric energy transmission are crimped together; It further includes the step of filling a sealant or solder between the aluminum conductor core and the cavity.

9. The preparation method according to claim 8, characterized in that: It further includes the step of providing a transition connection device on the aluminum conductor core.

Images