EP2724427B1

EP2724427B1 - Electrical connection system and its method of manufacture

Info

Publication number: EP2724427B1
Application number: EP12730473.1A
Authority: EP
Inventors: Frédéric MENEZ; Claude Casses; Arnaud Duquesne
Original assignee: Delphi International Operations Luxembourg SARL
Current assignee: Delphi International Operations Luxembourg SARL
Priority date: 2011-06-21
Filing date: 2012-06-21
Publication date: 2015-09-09
Anticipated expiration: 2032-06-21
Also published as: JP2014520380A; WO2012175612A1; EP2724427A1; JP5968433B2

Description

FIELD OF THE INVENTION

The instant invention relates to electrical connection systems and their methods of manufacture.

BACKGROUND OF THE INVENTION

An electrical connector usually comprises an electrically insulating housing defining a plurality of receptacles to receive electrical contacts. These electrical contacts are usually formed as the front ends of respective electrical wires. It is common to provide an electrical shield which surrounds these receptacles, so as to protect the electrical current running in the contacts from Electromagnetic Interferences (EMI) from the surrounding world.
It has also been provided a cable with an electrically conductive sheet that will surround the front ends of the electrical wires, and is provided flexible. One example can be found in WO 2006/132391 disclosing an electrical connection system according to the preamble of claim 1.
In order to promote protection from electromagnetic interferences, it is important to ensure a continuous electrical connection between the metallic shield of the connector and the sheet. This has been very problematic, in particular when the shield is of polygonal cross-section.
The instant invention has notably for object to mitigate those drawbacks.

-SUMMARY OF THE INVENTION

To this aim, it is provided an electrical connection system according to claim 1 and a method to manufacture an electrical connector system according to claim 14. The system comprises an electrical connector, a flexible sheet and an attachment system.
The electrical connector comprises a metallic shield having a rear portion with a polygonal cross-section.
The flexible sheet has a flexible electrically conductive front section which surrounds the rear portion of the metallic shield.
The attachment system surrounds the front section of the flexible sheet. The attachment system has rigid arms interconnected to correspond to the polygonal cross-section, and adjustment mechanisms which guide adjacent rigid arms relative to one another along a radial degree of freedom.
With these features, the adjustment mechanisms allow the rigid arms to move radially until they adapt tightly to the polygonal cross-section of the shield, with the flexible sheet caught in between. This enables to tightly fit the sheet to the shield.
In some embodiments, one might also use one or more of the features defined in the dependant claims.

BRIEF DESCRIPTION OF THE DRAWINGS

Other characteristics and advantages of the invention will readily appear from the following description of one of its embodiments, provided as a non-limitative example, and of the accompanying drawings.
On the drawings:

Fig. 1 is a perspective exploded view of an embodiment of the invention,
Fig. 2 is a perspective view of an electrically conductive sheet used for the cable of Fig. 1,
Figs. 3a and 3b are perspective views, respectively taken from beneath and from above, of a rigid arm,
Figs. 4a, 4b and 4c are views illustrating the assembly of the electrical connection system.

On the different Figures, the same reference signs designate like or similar elements.

DETAILED DESCRIPTION

Figure 1 shows an electrical connection system 1 which comprises an electrical connector 2, a cable 3 and a attachment system 4.
The electrical connector 2 comprises a hosing 5 made of an electrically insulating material, and defining a plurality of pathways of electrical connection. In the present embodiment, the electrical connector comprises two pathways 6a, 6b. The pathways 6a, 6b are open at a first end 2a which is to receive the electrical cable 3, and at an opposed second end 2b (not visible on Fig. 1) which is to receive electrical contacts from a complementary connector designed to mate with the electrical connector 2 (not shown either). In the purely illustrative embodiment, the pathways are right-angled. The axis along which the cable 3 is received inside the electrical connector 2 is axis X and the two pathways are located next to one another along direction Y. Direction Z is the third direction and corresponds here to the direction of mating with the complementary connector. At least at the first end 2a, the housing has a polygonal cross section (here a rectangular cross section).
The housing 5 is surrounded by a metallic shield 7 which is for example, provided as a thin sheet of metal which has been formed around the housing 5. This is in particular the case at the first end 2a of the electrical connector 2 where the shield also has a polygonal (rectangular) cross-section. The same profile could be provided all along the receptacles. The metallic shield might be accessible from the second end 2b of the electrical connector, so as to be contacted with a complementary shield of the complementary connector (not shown). In particular, the metallic shield 7 surrounds all the pathways, so as to reduce the electromagnetic interference between the pathways and the outer world.
As shown in the present embodiment, the electrical connector 2 may also comprise a cover 8 which surrounds the metallic shield 7, and may provide one or more specific functions. However, at this stage it is not considered essential for the present invention.
The cable 3 comprises a plurality of electrical wires 9a, 9b each corresponding to a given receptacle 6a, 6b of the housing 2. The electrical wires sensibly extend along the direction X, and have a first end which comprises a respective electrical contact 10a, 10b. These electrically conductive contacts are connected (for example by crimping) to an electrical core of the electrical wire, this core being surrounded by an insulating sheath 11a, 11b, respectively. Each wire may also comprise an individual shield between the sheath and the core, and insulated from the core. A seal 12a, 12b may also be provided to surround the front end of the respective sheath, so that the pathway 6a, 6b will be sealed from the rear after introduction therein of the electrical contact. A flexible sheet 13 surrounds the front end of the cable 3. In particular, it surrounds at the front end of the cable, all the electrical contacts and their respective seals. It extends from a front end 14a, which is open, and rear end (not shown) which is for example connected to the ground. It may be connected to the ground by being connected to the shields of the respective wires, 9a, 9b. The sheet 13 is electrically conductive, and is for example a braid knitted from conductive wires. For example, the second end of the sheet 13 is electrically connected to an internal shield of each respective wires 9a, 9b (insulatively comprised between the outer sheath and the inner core of the wire) in a manner known per se. The front portion 15 of the sheet 13 is sized to be placed around the metallic shield 7 at the first end of the electrical connector 2.
An attachment system 4 is provided to surround the front portion 15 of the flexible sheet 13, and to tightly fit this front portion in electrical contact with the rear end of the metallic shield 7 in a way which will be described in more details below with reference to Figs. 3a to 4c.
In particular, the attachment system 4 comprises two identical rigid arms 16a, 16b. The arm 16a will be described below in relation to Fig. 3a and 3b. This description also applies to the identical arm 16b. The arm 16a is right-angled, and has a profiled section which extends sensibly along half of the polygonal cross section of the metallic shield 7. It is symmetrical with respect to the Y-Z plane. The arm 16a has a first end 17a and a second end 17b. The first end 17a and the second end 17b are different, and are shaped to correspond to one another, so that a first end 17a of the first arm 16a may correspond to the second end 17b of a second arm 16b. The ends 17a and 17b are provided at two corners of the rectangular cross-section of the shield 7, and in particular in the present case, at two opposed corners along a diagonal of this rectangle. Thus, the arm 16a has a first arm portion 18a which extends from the first end 17a to an intermediate apex 19, and a second arm portion 18b which extends from the apex to the second end 17b. The apex 19 corresponds to the corner of the metallic shield which is intermediate the two corners corresponding to the ends 17a, 17b of the arm 16a.
The inner face 20 of the arm 16a may comprise grooves 21 which run from one end 17a to the other 17b along the sides of the metallic shield. The outer face 22 may comprise two imbricated guiding systems. The outer guiding system comprises ribs 23 which run from one end 17a to the other end 17b of the arm, and inner ribs 24 which also run between the two ends 17a, 17b, are located between the two ribs 23, and are protruding less than the outer ribs 23 with respect to the outer face 22. For example, no inner ribs are provided at the apex 19.
The first end 17a is provided with a peg 25 and the second end 17b is provided with a groove 26 which is complementary to the peg 25 and has an open end 27, and an opposed closed end 28. In the present embodiment, due to the symmetry, it has in fact two pegs and two complementary grooves, the shown peg being associated with the not shown groove, and the shown groove 26 being associated with the not shown peg. The groove 26 is oriented along a tangent direction, which is here a direction parallel to the other diagonal of the rectangle joining the first and second ends 17a, 17b. The pegs and grooves are provided on respective heads 30 which are resiliently flexible to be bent out of the Y-Z plane with respect to the respective carrying arm portion 18a, 18b.
Assembly of the electrical connection system will now be described in relation to Figs 4a, 4b and 4c. As a first step, the cable 3 is assembled to the housing 5. In particular, each wire 9a, 9b is inserted into a respective pathway 6a, 6b of the connector housing, so that the respective electrical contact 10a, 10b is entirely located inside the housing. The seals 12a, 12b tightly seal each pathway against any ingress of material from the rear. At the same time, the flexible sheet 13 is brought with its front portion 15 loosely surrounding the first end 2a of the electrical connector, and in particular surrounding and in loose contact with the rear portion of the shield 7.
At a second stage, the first arm 16a and the second arm 16b of the attachment system, which are provided separately, are assembled to one another by inserting the peg provided at the first end of the second arm 16b inside the slot at the second end of the first arm 16a. The open end 27 of the slot is used for this insertion. Thus, the first and second arms 16a, 16b are removably connectable to one another, and, at this stage, the first and second arms 16a, 16b, are also rotatably connectable to one another by rotation about an axis X₁ defined by the above mentioned peg. The peg is received at the closed end 28 of the groove 26 opposite to the open end 27. This position corresponds to a pre-adjustment condition of the two arms.
The two arms are placed around the front portion 15 of the sheet 13, for example by rotating the arms relative to one another around the axis X₁ until the opening 29 provided between the two opposite unconnected ends is sufficiently large to let the rear portion of the shield 7 and the front portion of the sheet 13 to be inserted therein.
One arm is provided in the correct position. For example, the second arm 16b is in tight contact with the neighbour portion of the sheet 13, which is thus maintained in close contact with the metallic shield 7. The first arm 16a is rotated around axis X₁ with respect to the second arm 16b to assemble to one another the first end 17a of the first arm to the second end 17b of the second arm in the opposite corner. As can be seen in Fig. 4c, the peg 15 of the first end of the second arm 16b is provided in the groove 26 of the second end of the second arm 16b. The peg 25 is carried on the head 30 which is made resiliently flexible with respect to the first portion 18a as indicated by arrow A on Fig. 3b about a bending axis parallel to the Z direction.
During assembly of the two arms as described above, the heads 30 will be resiliently deflect inward until the pegs 25 reach the groove 26 from their closed end side 28 thereby allowing the heads 30 to resiliently spring back toward their rest condition. However, the heads 30 may also remain slightly deflected at this stage, so as to obtain retention of the two arms to one another by friction.
At this stage, the rigid arms are interconnected to correspond to the polygonal cross section of the rear portion of the metallic shield, however with some level of play to accommodate the front portion 15 of the flexible sheet 13 in between. This play is provided by the possible sliding of the pegs 15 in the respective slots 26 in the two diagonally opposed corners. Thus, the two arms 16a, 16b are provided sliding with respect to one another along a so-called radial degree of freedom by the sliding of the pegs 15 in the grooves 26 along the two parallel tangent directions.
Movement of the two arms relative to one another, will expand or reduce the periphery of the polygonal cross section defined by the interconnected arms, depending on the direction of sliding.
Then, turning back to Fig. 1, a continuously adjustable link 31, such as a tie wrap, will be provided to surround the interconnected arms. It is highly flexible in order to bend sharply at the edges. It will be provided guided first by the two outer ribs 23 then, as it is tightened, by the internal ribs 24 of the arms. Its tightening will cause the relative movement of the two arms relative to one another along the radial degree of freedom until the arms are tightly fitted against the metallic shield 17 with the front portion of the sheet in between. Thus, an excellent electrical connection between the sheet and the shield is provided. This connection is tight and uniform.
In variant embodiments, the shield cross-section could be polygonal with a different amount of sides, for example, three sides or more than four sides. In such cases, the arms will be adapted accordingly. In any case, it is useful to use two arms which-are identical to one another, and surround the shield cross-section. Yet, more than two arms could be provided. The arms may each cover two sides of the cross-section, as shown, or a different number of sides, such as one side, and more than two sides (this variant also applies to the four-sided embodiment).

Claims

Electrical connection system comprising an electrical connector, a flexible sheet and an attachment system,
wherein the electrical connector (2) comprises a metallic shield (7) having a rear portion with a polygonal cross-section,
wherein the flexible sheet (13) has a flexible electrically conductive front section which surrounds the rear portion of the metallic shield,
wherein the attachment system (4) surrounds the front section of the flexible sheet, and is characterized by having rigid arms (16a, 16b) interconnected to correspond to the polygonal cross-section, and by having adjustment mechanisms (25, 26) adapted to guide adjacent rigid arms relative to one another along a radial degree of freedom.
Electrical connection system according to claim 1, wherein the attachment system further comprises a continuously adjustable link (31) which surrounds the rigid arms, and is lockable in an adjustment position where the rigid arms (16a, 16b) fit tightly around the rear portion of the metallic shield.
Electrical connection system comprising an electrical connector, a flexible sheet and an attachment system,
wherein the electrical connector (2) comprises a metallic shield (7) having a rear portion with a polygonal cross-section,
wherein the flexible sheet (13) has a flexible electrically conductive front section which surrounds the rear portion of the metallic shield,
wherein the attachment system (4) surrounds the front section of the flexible sheet, and has rigid arms (16a, 16b) interconnected to correspond to the polygonal cross-section, adjustment mechanisms (25,26) adapted to guide adjacent rigid arms relative to one another along a radial degree of freedom, and a continuously adjustable link (31) which surrounds the rigid arms, and lockable in an adjustment position where the rigid arms (16a, 16b) fit tightly around the rear portion of the metallic shield.
Electrical connection system according to any of claims 1 to 3, wherein a first arm (16a) has a first end (17a) removably connectable with an associated second end (17b) of a second arm (16b).
Electrical connection system according to any of claims 1 to 4, wherein a first arm (16a) has a first end (17a) rotatably connectable with an associated second end (17b) of a second arm (16b).
Electrical connection system according to any of claims 1 to 5, wherein a first arm (16a) has a first end (17a) maintained connectable with an associated second end (17b) of a second arm (16b) in a pre-adjustment condition.
Electrical connection system comprising an electrical connector, a flexible sheet and an attachment system,
wherein the electrical connector (2) comprises a metallic shield (7) having a rear portion with a polygonal cross-section,
wherein the flexible sheet (13) has a flexible electrically conductive front section which surrounds the rear portion of the metallic shield,
wherein the attachment system (4) surrounds the front section of the flexible sheet, and has rigid arms (16a, 16b) interconnected to correspond to the polygonal cross-section, wherein a first arm (16a) has a first end (17a) removably and rotatably connectable with an associated second end (17b) of a second arm (16b), wherein the first arm (16a) is maintained connectable with the associated second arm (16b) in a pre-adjustment condition, wherein the adjustment system further comprises adjustment mechanisms (25,26) adapted to guide adjacent rigid arms relative to one another along a radial degree of freedom, from the pre-adjustment condition to an adjustment condition, and wherein the attachment system further comprises a continuously adjustable link (31) which surrounds the rigid arms, and is lockable in an adjustment position where the rigid arms (16a, 16b), in their adjustment condition, fit tightly around the rear portion of the metallic shield.
Electrical connection system according to any of claims 1 to 7, wherein a first arm (16a) has a first end (17a) with a peg (25), and a second arm (16b), adjacent to the first arm (16a), has a second end (17b), associated with the first end (17a) of the first arm (16a), wherein the second end of the second arm has a guiding groove (26) receiving the peg (25), and extending in a tangent direction.
Electrical connection system according to any of claims 1 to 8, wherein all arms (16a, 16b) are identical.
Electrical connection system according to any of claims 1 to 9, wherein the arms are interconnected at corners of the polygonal cross-section.
Electrical connection system according to any of claims 1 to 10, wherein the flexible sheet (13) is a braid knitted from electrically conductive wires.
Electrical connection system according to any of claims 1 to 11, wherein the electrical connector comprises a housing defining receptacles (6a, 6b) for receiving electrical contacts (10a, 10b) to be electrically connected to electrical contacts of a mating electrical connector, and wherein said metallic shield (7) surrounds said receptacles.
An assembly for an electrical connection system according to any of claims 1 to 12 and comprising said electrical connector (2), said flexible sheet (13) and said attachment system (4).
A method of manufacturing an electrical connection system comprising:
- providing an electrical connector (2) with a metallic shield (7) having a rear portion with a polygonal cross-section,

- surrounding the rear portion of the metallic shield with a flexible sheet (13) having a flexible electrically conductive front section,

- surrounding the front section of the flexible sheet with an attachment system (4) having rigid arms (16a, 16b), the rigid arms being interconnected to correspond to the polygonal cross-section, and,

- adjusting the sheet (13) to the shield (7) with adjustment mechanisms (25, 26) of the attachment system adapted to guide adjacent rigid arms (16a, 16b) relative to one another along a radial degree of freedom.