EP2856572A1

EP2856572A1 - Interconnection assembly for vehicle devices and method of interconnection

Info

Publication number: EP2856572A1
Application number: EP13723714.5A
Authority: EP
Inventors: Claude Casses; Luc MAILLET
Original assignee: Delphi International Operations Luxembourg SARL
Current assignee: Delphi International Operations Luxembourg SARL
Priority date: 2012-05-30
Filing date: 2013-05-06
Publication date: 2015-04-08
Also published as: CN104521075A; CN104521075B; WO2013178433A1; JP2015521352A; KR20150028966A

Abstract

An interconnection assembly for electrically connecting a vehicle device (300) to a cable or wire. The assembly comprises a device,a terminal attached to a wire and a guiding housing (700). The device internally accommodates a busbar connection (310, 320). The guiding housing (700) guides the terminal through a device opening(390), from an unmated position, in which the terminal is not connected to the busbar connection (310, 320), to a mated position, in which the terminal is electrically connected to the busbar connection (310, 320).The guiding housing (700) may be also used for interconnecting a cable or wire shielding braid (790) to an electroconductive portion of the device housing (312), and/or for accommodating sealing means between the cable or wire and the device housing.

Description

INTERCONNECTION ASSEMBLY COMPRISING AN ELECTRIC DEVICE AND A WIRE AND METHOD INTERCONNECTION

Field of the invention

The invention relates to the field of high voltage connections in vehicles, and more particularly high- voltage connections for interconnecting automobile devices supplied with high power. Background of the invention

As schematically shown on Fig. 1, electric and hybrid vehicles 100 may comprise various electric devices such as a battery set 200 and a power inverter 300 to convert the DC power supplied by the battery set 200 to the AC power used by electric powertrains 400. These electric devices are often electrically interconnected with wire harnesses 500 and controlled by an electronic control unit 600. In these interconnection assemblies of the prior art, the connection between a wire and a device is made either directly at the wire end or with a connector.

Indeed, a wire end may comprise a lug crimped or welded at the wire end. Then the lug is screwed on a busbar or a stud attached to the device.

Alternatively, a connector mounted at the wire end is mated with a counterpart connector (for instance a receptacle socket if the connector at the wire end is a plug connector) mounted on a device. The patent application US2008/0026639 for instance describes a connector for mechanically and electrically interconnecting battery cells, to power converter and/or electrically driven motors.

Screwed electrical connections are usually not suitable for high power connections because they depend heavily on how strongly tightened the bolt is screwed. Screwed electrical connections are not reliable in terms of contact points and aging.

Connectors are usually more reliable but require the use of a socket and shift connection issues at the level of the socket to device connection.

An aim of the invention is to mitigate these drawbacks.

Summary of the invention

According to the invention, an interconnection assembly is provided for electrically connecting a cable or wire to a vehicle device. The connection assembly according to the invention comprises a device, at least one wire or cable and a guiding housing.

The device is advantageously a part of a high power electrical circuit. It may be for example a battery set, a converter, an electric motor, a junction box or any other type of electric component. In high power circuits, the voltage range may be from 40V up to 800V, depending on type of battery and number of battery cells, and the current range reaches from extremely low currents of some 10 mAmp to permanent high currents of up to 600 Amps and peak currents of up to 1.5 kAmps.

The device has a housing with at least one opening. Indeed, the device housing accommodates at least one busbar connection for feeding the device with electric power. The device housing protects the busbar connection to be connected with the wire, as long as the device is not mounted in a vehicle. In this sense, the busbar connection is accommodated inside (i.e. internal to) the device housing.

The wire or cable has an end provided with a terminal accommodated in the guiding housing adapted to be mounted on the device housing.

At least one opening is required in the device housing, through which the wire terminal is inserted for electrically connecting the wire to the busbar connection. Such an opening is designed so as to insert a pin, a blade, a male or a female terminal, or any other kind of terminal for contacting the busbar connection located internal to the device housing. The busbar connection may also be a pin, a blade, a male or a female terminal, or any other kind of connecting element or terminal which can be mated with the wire terminal. Advantageously, the busbar connection is directly electrically connected to a respective device pole.

An advantage of this configuration is that there is no any pin or any other connecting part which sticks out of the device housing while the device is not connected. There is consequently less risk to damage the connecting parts before or after it is mounted in the vehicle. A plug can be used for filling/ closing the opening(s) if the device is not connected.

The guiding housing guides the terminal through the device opening, from an unmated position, in which the terminal is not connected to the busbar connection, to a mated position, in which the terminal is electrically connected to the busbar connection.

The guiding housing is a kind of connector but its role is mainly to guide the wire terminals during the mating. The guiding housing may not interfere itself with the mating counterpart, i.e. the busbar connection. The interconnection assembly according to the invention allows connecting wires and cables, and in particular high power cables in motorized vehicles, to an electrical device such as an electric motor of powertrain, an inverter, etc. as a single interconnection device but without screwing the cable terminal on a device stud.

If the cable is composed of a strand with several wires (for example for connecting

2 or 3 ways in straight exit), each wire is provided with a male or female terminal and the guiding housing allows plugging/mating directly these terminals on respective busbar connections such as device studs or any counterpart terminal mounted in the device. Therefore, these cable terminals are mounted on a single support, the guiding housing, that can be attached on the device housing. Sealing and shielding are managed between the support and the housing. For instance, sealing performances meet IP67&IPx9K requirements.

This solution has the advantages of a unique interconnection and of avoiding having screwed electrical connections. An interlock may be incorporated in the guiding housing or linked to a micro-switch.

Advantageously, the guiding housing is made of insulating material and the terminal comprises an insulating cap. This is particularly advantageous for embodiments of the guiding housing which are designed so as to have the wire terminals not extending (or only slightly) out of the guiding housing. Such a configuration may then be designed for meeting IP2X requirements.

The interconnection assembly according to the invention is as robust and reliable from the electrical connection standpoint as the best prior art connectors. It has further the advantage of reducing the assembly time at the harness maker's and/or supplier's, and remains quite easy to connect or disconnect for maintenance operations.

The interconnection assembly according to the invention has also the advantage of having a reduced number of parts compared to a prior art connector, which is better from the manufacturing and logistics standpoint.

According to another aspect, the invention relates to a method of interconnection for connecting at least one wire to an electric device. This method of interconnection comprises the following steps:

- providing at least one wire, one wire terminal, one guiding housing and one electric device with at least one opening and one busbar connection;

- electrically coupling the wire and the terminal;

- inserting the terminal in the guiding housing;

- inserting the guiding housing in the opening of the device, so as to guide the terminal through the device opening, from an unmated position, in which the terminal is not connected to the busbar connection, to a mated position, in which the terminal is electrically connected to the busbar connection; and

- fastening the guiding housing to the device housing.

For fastening the guiding housing to the device housing, many fastening means may be used, such as screws, latches, etc.

Other features and advantages of the invention will be set forth in, or apparent from, the following description and of the appending drawings.

Brief description of the drawings On the drawings:

Figure 1 schematically represents a vehicle comprising a high power electrical circuit with a battery set, a power inverter, an electric motor and an electronic control unit;

Figures 2A and 2B schematically represent in perspective, from above and from below, an example of interconnection assembly according to the invention;

Figure 3 is a schematic exploded view in perspective of the guiding housing of interconnection assembly of figure 2A and 2B;

Figure 4A to 4E show cable assembly operations for mounting the guiding housing represented on Figs. 2A, 2B and 3;

Figure 5A and 5B are schematic exploded views in perspective schematically representing the assembly process of the busbar connection for the interconnection assembly of Figs. 2A and 2B.

On the different figures, the same references signs designate like or similar

Detailed description

Figs. 2A and 2B illustrate an exemplary embodiment of the interconnection assembly according to the invention. Such an interconnection assembly is for example part of a power circuit as the one described above in relation to Fig. 1.

The interconnection assembly of Figs. 2A and 2B comprises a device 300 (such as a power inverter), a harness 500 and a guiding housing 700. On these figures, the device 300 is only partially and schematically represented. Two harnesses 500 are shown, respectively a 2-ways harness and a 3-ways harness. Accordingly, the device 300 comprises two busbars, respectively a 2-ways busbar 310 and a 3-ways busbar 320. Each one of these busbars 310, 320 comprises an insulating support 311 or 321.

Fig. 3 shows more details of the guiding housing 700. The guiding housing 700 comprises an insulating support 710, an electrically conductive cover 720 and a seal 730.

The support 710 accommodates three terminals 740, 750, 760 and a shorting member 770. In this embodiment, the terminals 740, 750, 760 are male terminals or pins.

An insulating plastic cap 755 covers each terminal tip 756. Once mounted in the guiding housing 700, the terminals 740, 750, 760 will not extend (or only slightly) out of the guiding housing 700. The caps 755 will then protect the terminal tips 756 in order to meet IP2X requirements.

Each one of them is connected (welded or crimped for example) to a respective wire 780 (only one wire is represented on Fig. 3). Each wire 780 is for example composed of a conductive braid 781 wrapped in an insulating sheath 782. The end of the sheath 782 is stripped off and the braid end is inserted in a crimping portion 741 of the corresponding terminal 740. Prior to this crimping operation, a single wire seal 742 and a retainer 743 were slipped on each wire sheath 782.

Subsequently, after the crimping operation, as shown on Figs. 4A to 4E, terminals 740, 750, 760 are inserted in respective support cavities 711, 712, 713 (Fig. 4A). Each single wire seal 742 is pushed and slid in a respective cavity 711, 712 or 713 (Fig. 4B).

Then, each retainer 743 is also pushed and slid at the backside of the cavities. Retainers 743 have protrusions designed to engage respective holes of the support 710 so as to maintain the seals 742, in their respective support cavities 711, 712, 713 (Fig. 4C).

As shown on Fig. 4D, a shielding braid 790 is slid at the backside of the support 710 so as to overlap a cylindrical flange 721 of the conductive cover 720. A clamping collar 722 is then tightened over the shielding braid for maintaining and pressing it on the conductive cover 720 (Fig. 4E). The conductive cover 720 also comprises a fastening plate 723 which extends substantially perpendicular to the cylindrical flange 721. The fastening plate 723 covers a fastening collar 715 of the support 710 (see Fig. 3) and ensures the electrical connection between the shielding braid 790 and the device 300 on which the harness 500 is mounted.

As shown on Figs. 5 A and 5B, a busbar 320 comprises an insulating support 321, and three female terminals 330, 340, 350. Each female terminal is made of a connection portion 331 mounted on a conductive plate 332. The conductive plate 332 is for instance made of a copper bus sheet metal at least 1.2 mm thick. For example, the conductive plate 332 may be directly mechanically and electrically connected to a pole 380 of the device 300.

Connection portions 331 are accommodated in channels 333 of the insulating support 311 or 321. The distal end of each channel 333 has an annular skirt 334 extending perpendicular to the longitudinal axis of the channel 333. Skirts 334 protect the elastic blades 335 of the connection portions 331 , when a male terminal is mated in a female terminal 330, 340 or 350.

The support 321 also comprises two cavities 323, each one of which accommodating an interlock terminal 336. Coming back to Fig. 2B, the support 311 or 321 is mounted in a device housing 312 so as to have the channels 333 overlapped by the mating opening 714 (see also Fig. 3) of the support 710, located at the mating front of the guiding housing 700, and to allow the mating of the male terminals 740, 750, 760 with a respective connection portion 331. Once each male terminal 740, 750, 760 mated with a respective connection portion 331, the shorting member 770 interacts with the interlock terminals 336 so as to close an interlock circuit and to trigger the supply of power in the power terminals 740, 750, 760 and connection portion 332.

As shown on Fig. 2A, the fastening collar 715 and the fastening plate 723 can then be screwed on the device housing 312. Consequently, it can be seen that the mechanical coupling of the harness 500 with the device 300 and the electrical coupling of the shielding braid 790 with the conductive portion of the device 300 are provided by fastening means 715, 723, while the electrical connection between the harness wires 780 and the device 300 is provided by the terminals 740, 750, 760 and the busbar 310 or 320 located inside the device 300, through a device opening 390.

According to another aspect, the invention relates to an interconnection method of the invention:

a harness 500 is provided with at least one wire 780, one single wire seal

742, one shielding braid 790 and one retainer 743;

a terminal 740, 750 or 760 is attached to the wire 780;

the terminal 740, 750 or 760 is then inserted in a guiding housing 700 and the single wire seal 742 and the retainer 743 are placed and blocked behind the terminal 740, 750 or 760 at the back of the guiding housing 700; the shielding braid 790 is drawn up to the fastening plate 723 and a clamping collar 722 is fastened around the shielding braid 790; the guiding housing 700 is inserted in the device opening 390 and the wire terminal 740, 750 or 760 is mated with a connection portion 331 of the busbar connection 310 or 320; and

the guiding housing 700 is fastened, for example screwed, on the device housing 312.

While an exemplary embodiment has been presented in the foregoing description, it should be appreciated that a many variations exist. For example, the assembly according to the invention may comprise a motor (instead of a power inverter), or any kind of electrical device.

Claims

1. An interconnection assembly comprising

an electric device (300) having a housing (312) with at least one opening (390),

at least one wire (780) having an end provided with a terminal (740) accommodated in a guiding housing (700) adapted to be mounted on the device housing (312),

wherein the device housing (312) accommodates at least one busbar connection (310 or 320) for feeding the device (300) with electric power, and

wherein the guiding housing (700) guides the terminal (740) through the device opening (390), from an unmated position, in which the terminal (740) is not connected to the busbar connection (310 or 320), to a mated position, in which the terminal (740) is electrically connected to the busbar connection (310 or 320).

2. Interconnection assembly according to claim 1, wherein the electric device (300) is an inverter or electric powertrain motor for a motorized vehicle and the busbar connection (310 or 320) is directly electrically connected to at least one device pole (380).

3. Interconnection assembly according to claim 1 or 2, wherein a shielding braid (790) surrounds at least partially the wire (780) and the guiding housing (700) comprises an conductive cover (720) for electrically connecting the shielding braid (790) to a conductive portion of the device housing (300).

4. Interconnection assembly according to one of the preceding claims, wherein a seal (730) is mounted between the guiding housing (700) and the device housing (712).

5. Interconnection assembly according to one of the preceding claims, wherein the busbar connection (310, 320) is protected by an insulating support (311, 321).

6. Interconnection assembly method according to one of the preceding claims, wherein the guiding housing (700) is made of insulating material and the terminal (740, 750 or 760) comprises an insulating cap (755).

7. Method of interconnection of at least one wire (780) with an electric device (300), comprising the following steps:

- providing at least one wire (780), one wire terminal (740, 750or 760), one guiding housing (700) and one electric device (300) with at least one opening (390) and one busbar connection (310 or 320);

- electrically coupling the wire (780) and the terminal (740, 750or 760);

- inserting the terminal (740, 750or 760) in the guiding housing (700);

- inserting the guiding housing (700) in the opening (390) of the device (300), so as to guide the terminal (740, 750or 760) through the device opening (390), from an unmated position, in which the terminal (740, 750or 760) is not connected to the busbar connection (310 or 320), to a mated position, in which the terminal (740, 750or 760) is electrically connected to the busbar connection (310 or 320);

- fastening the guiding housing (700) to the device housing (312).

8. Method according to claim 7, wherein the electric device (300) is an inverter or electric powertrain motor for a motorized vehicle and the busbar connection (310 or 320) is directly electrically connected to at least one device pole (380).