EP2579390A1 - Aluminium-copper terminal and method for manufacturing the same - Google Patents

Abstract

The aluminum-copper terminal (100) has an aluminum made contact structure (101) for electrically connecting a primary region of the aluminum-copper terminal to the current-carrying aluminum cable (401), and a copper connector (102) for connecting secondary portion of the terminal to the current-carrying element. The contact structure is connected to copper connector at a connecting portion. A primary seal is provided at step section between contact structure and copper connector. A secondary seal (301) is arranged to protect the primary seal from environmental condition. Independent claims are included for the following: (1) method for manufacturing aluminum-copper terminal; (2) vehicle; (3) power supply network; and (4) power plant.

Description

The invention relates to the technical field of connection technology. In particular, the invention relates to a method for producing an aluminum-copper terminal, an aluminum-copper terminal, a vehicle with an aluminum-copper terminal, a power supply network with an aluminum-copper terminal and a power plant with an aluminum-copper Terminal.

Background of the invention

For electrically connecting current-carrying cables with other current-carrying elements so-called. Terminals or connecting parts can be used. The cable is connected to the terminal on one side of the terminal with the terminal and then on the other side of the terminal, the current-carrying element can be connected. For example, the other side of the terminal for connection to the current-carrying element is designed in the form of a cable lug, which has a flat contact surface with a bore for receiving a fastening bolt or a screw.

When using aluminum cables, which are light and inexpensive, designed the electrical contact, ie the production of an electrically conductive connection, between the current-carrying aluminum cable and the Current-carrying elements often difficult. Crimp connections are usually not sufficient because the aluminum tends to cold flow and thus decreases the contact force. This causes a deterioration of the electrical contact and can thus lead to overheating or in the worst case to the interruption of the circuit.

Furthermore, aluminum forms in air an oxide layer which is not electrically conductive. An additional problem with connecting aluminum cables to other metallic, live elements, e.g. Copper, brass or steel is the so-called electrocorrosion. This electrochemical process occurs in the presence of two metals with different potentials from the electrochemical series and an electrolyte (e.g., salt water). The less noble metal is broken down. Thus, the use of a shrink tube may be required to protect the electrical contact between aluminum and copper.

Summary of the invention

It is an object of the invention to provide an alternative manufacturing method for producing an aluminum-copper terminal, by means of which the joint between the individual elements of the terminal can be reliably sealed and which enables optimum electrical contacting of an aluminum cable and another current-carrying element.

According to a first aspect of the invention, a method for producing an aluminum-copper terminal is provided, which is designed for electrically connecting a current-carrying aluminum cable with a current-carrying element.

In the method, an aluminum contact part of the terminal is connected to a copper terminal part of the terminal. This connection takes place in a connection region and serves to produce an electrically conductive connection between the two parts.

This is followed by a media-tight, that is, for example, airtight and / or watertight sealing of the connecting region by attaching a primary seal, which firmly adheres to the contact part and the connection part.

All this already happens during the production of the terminal. The application of a heat shrink tubing in a final step, after the aluminum cable is already connected to the terminal, is no longer necessary, but can be done additionally, but is not necessary to avoid electrocorrosion and serves only to cover the aluminum Contacting, the insulation crimp and the welding area up to the primary / secondary sealing.

As a result, an early electrical corrosion of the contact point between the aluminum contact part of the terminal and the continuing copper connector can be avoided. Furthermore, this can be the installation steps that must be performed by the user to be reduced.

In principle, it is sufficient if the user electrically connects the aluminum cable to the terminal. Due to the media density, ie, for example airtight sealing of the connection area between the aluminum contact part and the copper connection part of the terminal, the electrical corrosion of the connection point is avoided, so that the electrical conductivity of the connection point decreases little or no over time.

The contact part of the terminal is used to electrically connect a first area of the terminal, for example the rear end of the terminal, to the live aluminum cable. The connection part serves to electrically connect a second area of the terminal, which is, for example, its front end, to the current-carrying element.

Thus, by using aluminum at the cable terminal side and copper at the contacting side and at the same time eliminating unwanted electrocorrosion, e.g. By reliably sealing off the critical transition region from aluminum to copper, an optimal contacting of an aluminum cable and another current-carrying element takes place.

It should be noted in the following that the device features of the terminal described below can also be implemented by corresponding method steps in the production of the terminal.

According to a further aspect of the invention, the attachment of the primary seal around the connection region of the terminal takes place by insert molding of the connection region. Alternatively, the primary seal can also be embodied in the form of a sealant, which is pressed against the connection region or otherwise applied. Also, the sealing may be, for example, two half-shells which are provided on their inner surfaces with a sealing gel or the like, and which are wrapped around the connecting region so that it is sealed by the gel. As a seal special thermoplastics or hotmelts, which can be applied by injection molding, or sealing compounds or Knetmassen or silicone materials are used.

According to a further aspect of the invention can be carried out after the attachment of the primary seal attaching a secondary seal to the primary seal.

The secondary seal can be, for example, an impact-resistant plastic or an impact-resistant thermoplastic in the form of a mechanically protective housing.

The connection of the aluminum contact part with the copper connection part for producing the electrically conductive connection between these two parts can be done for example by ultrasonic welding. In the same way, the aluminum cable can also be attached to the aluminum contact part in a later method step. In particular, it is possible that the aluminum cable is welded to the aluminum contact part after the primary seal and, if present, the secondary seal are attached.

In other words, therefore, the aluminum-copper terminal can be finished and sealed by the manufacturer. Then it is delivered to be connected on one side to the aluminum cable and on the other side to the other current-carrying element.

Thereafter, a shrink tube may be placed around the aluminum contact portion and the copper termination to provide additional protection and seal. This shrink tube may also extend around the end portion of the aluminum cable.

According to a further aspect of the invention, an aluminum-copper terminal for electrical connection of a current-carrying aluminum cable is given with a current-carrying element. This terminal is used, for example, by the prepared above manufacturing method. The terminal has an aluminum contact portion for electrically connecting a first portion of the terminal to the live wire. In addition, a connection part, which comprises copper or consists of copper, is provided, which serves to connect a second area of the terminal to the current-carrying element. By way of example, the copper connection part is provided with a coating, for example a nickel layer.

In addition, a primary seal is provided, which closes the connection region between the contact part and the connection part in a media-tight manner to the outside and firmly adheres to the contact part and the connection part.

By way of example, this primary seal may be a soft, elastic seal, which in particular prevents the contact surface between the two parts from being contaminated with an electrolyte, e.g. Salt water, comes into contact.

According to a further aspect of the invention, the terminal further comprises a secondary seal made of impact-resistant plastic, which completely covers and protects the primary seal, since the primary seal is especially for sealing, but can be very sensitive. This secondary seal may, for example, in addition to its outer side have a corrugation, which favors a firm adhesion of the shrink tube to the terminal.

According to a further aspect of the invention, the primary seal is sprayed onto the connection point between the contact part and the connection part. The contact part and the connection part are welded together to form the conductive connection between these two parts. However, they are Other types of connections between the contacts and the connection part possible.

According to a further aspect of the invention, the connection part is designed as a cable lug. According to a further aspect of the invention, the connection part is designed as a pole terminal of a battery.

According to a further aspect of the invention, there is provided a vehicle having an aluminum-copper terminal described above and hereinafter. For example, the terminal may be used to connect an aluminum lead to the pole of a battery of the vehicle and may be used to contact aluminum cables in the engine compartment exposed to extreme environmental conditions such as heat, cold, dew, fuel spray, vibration, salt water.

According to a further aspect of the invention, a power supply network is provided with an aluminum-copper terminal described above and below. In this case, the terminal may be a terminal designed for the low voltage or medium voltage range. In particular, the terminal may be designed for high currents, as may occur in such networks. In particular, the terminal can be used in wind turbines. In the tower of the wind turbine high-flexible copper cables are used starting from the generator, which participate all rotations and movements of the generator; however, aluminum pipe is often used to redistribute and distribute energy. In the transition area just such an aluminum-copper terminal is needed again.

According to a further aspect of the invention, a power plant is specified with an aluminum-copper terminal described above and below. The power plant is, for example, a wind power plant, a coal power plant, a photovoltaic power plant or a hydroelectric power plant.

In the following, embodiments of the invention will be described with reference to the figures. In the following figures, like reference numerals may refer to the same elements. The same elements can also be designated by different reference numerals.

Brief description of the figures

• Fig. 1A to 1D show four views of a terminal according to an embodiment of the invention after performing the first manufacturing steps.
• Fig. 2A to 2D show the terminal of Fig. 1A to 1D after another production step.
• Fig. 3A to 3D show the terminal of Fig. 2A to 2D after another production step.
• FIGS. 4A to 4C show the terminal of Fig. 3A to 3D after connecting a cable.
• Fig. 5 shows a terminal according to an embodiment of the invention, in which the connecting part is designed as a battery terminal.
• Fig. 6 shows a vehicle with a terminal according to an embodiment of the invention.
• Fig. 7 shows a power supply network with power plants, rear derailleurs and end users, and a plurality of terminals according to an embodiment of the invention.
• Fig. 8 shows a flowchart of a method according to an embodiment of the invention.

Detailed description of embodiments

Fig. 1A shows a sectional view of a terminal 100 according to an embodiment of the invention along its longitudinal axis AA (see Fig. 1C ).

The terminal 100 has a contact part 101 which, for example, is made of aluminum or at least comprises aluminum or an aluminum alloy. Electrically conductive is connected to a connection part 102, which consists for example of copper or at least copper or a copper alloy. The connection part can also be coated with nickel or another metal, in particular or exclusively in the region of the conductive connection between the two parts 105.

Moreover, the aluminum contact part 101 may have at its left end two webs 103, 104, which may be used as insulation crimp.

Fig. 1B shows a side view of the aluminum-copper terminal, from which in particular the shape of the two webs 103, 104 can be seen prior to fixing the current-carrying cable. The two webs 103, 104 each have one vertical flank and an inclined flank, wherein the one web 103 has the sloping flank at its front and the other web 104, the oblique flank at its rear side, so that the two mutually opposite webs 103, 104 can be bent towards each other, without getting lost to obstruct (see for example Fig. 4A ).

From the Fig. 1C It can be seen that the contact surface 105, along which the conductive connection between the aluminum contact part and the copper connection part is made, may have a smaller extent than the aluminum contact part located underneath or the copper connection part 102 located above it.

It can also be provided that the terminal narrows in the connection region 105, and that the side edges 106, 107 of the aluminum contact part 101 1 overlap the corresponding side surfaces 108, 109 of the copper connection part 102. In other words, both parts 101, 102 are narrower in the contact area 105 than in the remaining area to make room for the sealing / encapsulation of this area, so that the seal then protrudes as little as possible from the finished component.

The aluminum contact part has, between the contact area 105 and the two crimp bars 103, 104, a flat area 115 on which the current-carrying aluminum cable (see FIG FIGS. 4A to 4C ) can be welded.

The copper terminal 102 also has a flat portion 114 located at the right end thereof. This region 114 is for connection to the current-carrying element (not shown) and has, for example, a recess in the form of a bore 110 or punched-out in order to fix the end region 114 of this part 102 to the current-carrying element.

For example, to facilitate insertion into a corresponding socket of the current-carrying element, the front side 111 of the copper connection part 102 may be rounded or circular-arc-shaped.

How out Fig. 1D As can be seen, the copper connection part 102 is designed in the form of a cable lug and has a step 112, which is located between the contact region 105 and the connection region 114.

The rear portion 113 of the aluminum contact portion 101, which lies between the two crimping ribs 103, 104, may have a curved surface, which is modeled on the cross section of the cable to be absorbed.

Fig. 2A shows a cross-sectional view of the terminal 100 of Fig. 1A to 1D after the primary seal 201 has been applied. The Fig. 2B to 2D show more representations of the terminal of Fig. 2A in side view, in plan view and in perspective.

Between the aluminum cable to be attached later and the aluminum contact part 101 and between the aluminum contact part and the copper connection part 102 there are intermetallic, electrically conductive connections. These connections are generated for example by ultrasonic welding. To prevent electrocorrosion, the primary seal 201 is applied. In this case, the primary seal closes the connection region 105 between the connection part 102 and the contact part 101 in a media-tight manner, ie airtight and / or in particular oxygen-tight, and also adheres firmly to the contact part 101 and the connection part 102.

The primary seal may be cuboid, so that a fixation of a later attached secondary seal is favored.

By attaching the primary seal, electrocorrosion of the contact area between the two parts 101, 102 can be effectively prevented. In addition, the terminal can also be used in wet areas without the conductivity deteriorating.

Fig. 3A shows a sectional view through the terminal 100 along its longitudinal axis, now a secondary seal 301, for example made of plastic, has been attached to the primary seal 201.

The secondary seal 301 in this case can develop a mechanical protection against damage to the primary seal and can be made for example of impact-resistant plastic.

The secondary seal may in particular be designed in the form of a housing, which is designed, for example, in two parts and is placed around the primary seal. Also, the secondary seal, like the primary seal, can be sprayed on.

The secondary seal may have a corrugation to promote the adhesion of a subsequent shrink tube. The corrugation is transverse to the component, since the shrink tube during "shrinking" tends to contract in the longitudinal direction and thus could possibly slip off the seal.

The in the Fig. 3A to 3D shown embodiment of the terminal can then be supplied in this form to the user. The user thus receives a ready Sealed system in which the critical transition from aluminum to copper is already sealed by the manufacturer.

Such terminals can be used both in the vehicle sector as well as in the field of power generation (power plant technology) and energy distribution, and generally in the electrical sector.

As an alternative to the primary seal and / or the secondary seal described above, sealants, gel-filled half-shells, etc. may be used.

The FIGS. 4A to 4C show a perspective view, a side view and a top view of a terminal 100 with an attached cable 401. The cable 401 has an outer insulation and a lying therein strand (cable), for example, made of aluminum. The strand terminates in a flat, widened end 402, which comes to lie on the contact region of the aluminum contact part 101 which extends between the two crimping webs 103, 104 and the contact region 105 (see FIG Fig. 1C ) is located at the end of the aluminum contact part 101.

In this area, the aluminum strand is ultrasonically welded to the aluminum contact part, for example.

Before the welding or thereafter, the two crimping webs 103, 104 can be bent inwards in order to lay around the insulation of the aluminum strand and additionally mechanically fix the cable.

In Fig. 4B is the flat portion 403 of the aluminum connector 101 to see on which the strand 402 is welded.

The seal 201, 301 in the joining region 105 of the two parts 101, 102 excludes an oxygen supply to the contact point and thus an electrical corrosion. This sealing of the joining region can take place in the form of an automated process, which directly follows the welding process of the two parts 101, 102. Since this process is carried out and monitored directly by the manufacturer, a high standard of quality can be ensured.

Fig. 5 shows another embodiment of the terminal 100, in which the copper terminal part is designed in the form of a sheet-metal battery terminal 501, which can be placed around the pole of a car battery.

Fig. 6 1 shows a motor vehicle 600, which may be, for example, a lorry or a passenger car, and which has one or more terminals 100.

Fig. 7 FIG. 3 shows a power supply network 700 with multiple power plants 701, 707. Both the wind power plant 707 and the coal power plant 701 have a plurality of terminals 100. From these power plants leads 702 to corresponding transformer stations 703, 708. These transformer stations, which are designed to transform the current, have a plurality of terminals 100. From the transformer stations then lead lines 704, 709 to the households 705, 706, which may also have terminals 100.

Wherever the transition from copper cables to aluminum cables occurs, a "sealed" terminal as described above may be used.

Fig. 8 shows a flowchart of a method according to an embodiment of the invention. The copper connection part can be designed as a stamped part or forged part. For example, the punching or forging of the copper connection part as well as the stamping or forging of the aluminum contact part takes place at the manufacturer of the terminal. After these first two steps 801, 802, a surface treatment of the copper connection part may take place in step 803. For example, the surface is nickel plated. Thereafter, in step 804, a welding of the copper connection part to the aluminum contact part takes place, and in step 805 the sealing of the weld is then carried out by an encapsulation with the primary seal.

In step 806, it is then optionally possible to attach a secondary seal in the form of a plastic housing. The above steps are done by the manufacturer in a supervised process. The user can then be done in step 807 welding the aluminum cable to the aluminum contact piece. In step 808, the isolation claws or crimping ribs 103, 104 are transferred. In step 809, a heat shrink tubing may be further attached.

In addition, it should be noted that "comprising" and "having" does not exclude other elements or steps, and "a" or "an" does not exclude a plurality. It should also be appreciated that features or steps described with reference to any of the above embodiments may also be used in combination with other features or steps of other embodiments described above. Reference signs in the claims are not to be considered as limitations.

Claims (18)

Aluminum-copper terminal for electrically connecting a live aluminum cable to a live element, comprising the aluminum-copper terminal: an aluminum contact portion (101) for electrically connecting a first portion (403) of the terminal (100) to the live lead (401); a connector (102) comprising copper for connecting a second region (114) of the terminal (100) to the current-carrying element; wherein the contact part (101) is conductively connected to the terminal part (102) at a connection area (105); wherein the critical transition region between the contact part and the connection part already on the manufacturer side, for example by an encapsulation, is sealed so far that the component electrical corrosion can be largely avoided. Aluminum-copper terminal according to claim 1, in which the user no longer has to worry about the sealing. Aluminum-copper terminal according to one of the preceding claims, comprising: a primary seal (201); wherein the primary seal (201) closes the connection area (105) in a media-tight manner and firmly adheres to the contact part (101) and the connection part (102). Aluminum-copper terminal according to one of the preceding claims,
further comprising a secondary seal (301) made of impact-resistant plastic, which completely covers the primary seal (201). Aluminum-copper terminal according to one of the preceding claims, wherein the primary seal (201) consists of an elastic material. Aluminum-copper terminal according to one of the preceding claims,
wherein the secondary seal (301) has a corrugation on its outer side. Aluminum-copper terminal according to one of the preceding claims,
wherein the primary seal (201) is sprayed on the contact part (101) and the connection part (102). Aluminum-copper terminal according to one of the preceding claims,
wherein the contact part (101) is welded to the connection part (102) in order to form the conductive connection and to ensure the best possible connection and conductivity through an intermetallic connection. Aluminum-copper terminal according to one of the preceding claims, wherein the connecting part (102) is designed as a cable lug. Aluminum-copper terminal according to one of claims 1 to 8,
wherein the connection part (102) is designed as a pole terminal of a battery. A method of manufacturing an aluminum-copper terminal (100) adapted to electrically connect a live aluminum cable to a current-carrying element, the method comprising the steps of: Bonding an aluminum contact part (101) to a copper terminal part (102) at a connection area (105) for establishing an electrically conductive connection between the two parts (101, 102); hermetically sealing the joint area (105) by attaching a primary seal (201), eg by injection molding with a special thermoplastic, the primary seal adhering firmly to the contact part (101) and the connection part (101); wherein the contact part (101) is designed to electrically connect a first area (403) of the terminal (100) to the current-carrying cable (401); wherein the connecting part (102) is designed for electrically connecting a second area (114) of the terminal (100) to the current-carrying element. Method according to claim 11,
wherein the attachment of the primary seal (201) by encapsulation of the connection region (105) takes place. The method of claim 11 or 12, further comprising the step: Attaching a secondary seal (301) around the primary seal (201). Method according to one of claims 11 to 13,
wherein, after attaching the primary seal (201) and optionally after attaching the secondary seal (301) welding of the aluminum cable to the aluminum contact part (101). Method according to claim 14,
wherein, after the aluminum cable has been welded to the aluminum contact part (101), a heat-shrinkable tube is attached around the aluminum contact part (101) and the connection part (102). Vehicle (600) with an aluminum-copper terminal according to one of Claims 1 to 10. Power supply network (700), wherein the transition from an aluminum line to a copper line is formed with an aluminum-copper terminal according to one of claims 1 to 10. Power plant (701, 707) with an aluminum-copper terminal according to one of claims 1 to 10.

Images