GB2354641A - Electrical connector with multiple contacts - Google Patents

Abstract

A connector 12 has contacts 80 which project through a housing 22 and are axially movable, and a skirt 46. The counterpart 16 has a tube 158 which lines up with the skirt 46, and contacts (150, Fig 2) mounted on a support (152, Fig 2). A bolt 50 or the like holds the two connectors together. An elastically deformable washer 70 presses the first contacts onto the second contacts, distributing the contact pressure substantially uniformly over the contact surfaces. The connector may be used for an alternator or motor in a vehicle.

Description

2354641 "Electrical connector with multiple contacts" The invention

relates to an electrical connector with multiple contacts.

Certain devices such as electrical generators or motors have to be linked electrically to a second device such as a control system. Each phase of one of the devices has to be linked to the corresponding phase of the other device. This link may be obtained by direct contact between the corresponding phases of the two devices but, in a general way, it is formed by cables comprising several electrical wires each of which makes it possible to link one phase.

It is thus necessary to form an electrical connection between the end of each wire and the corresponding phase of the device.

one solution consists in putting one end of a wire in contact with the corresponding conducting area of the device and keeping them in contact via a screwed assembly. This solution exhibits several drawbacks.

On the one hand, it is necessary to carry out as many assembly operations as there are electrical connections to be formed, which gives rise to significant cost to the extent that the number of components as well as the fitting time are multiplied by the number of connections to be formed. Moreover, the contacts are formed by simple pressure between the conducting areas of the device and of the cable, and they are then subjected to vibration as well as to the external conditions, which increases the risk of corrosion and of deterioration of the electrical contact.

2 French patent No 96.12609, published under the number FR-A-2 7S4 650 proposes an electrical connection which makes it possible, at one single fixing point, to provide a plurality of electrical contacts between two electrical devices. The electrical connection proposed also ensures sufficient leaktightness to protect the electrical contacts against corrosion.

The electrical connection element is composed of two parts, male and female, each including at least two conducting elements each corresponding to one electrical phase. These two parts are put in contact by a single means, such as a nut-and-bolt assembly, which makes it possible to clamp the male part against the female part.

However, the connection element does not allow for a reliable electrical contact between the corresponding conducting elements. This is because, if the conducting elements are not of exactly the same length or if their contact surfaces are not perfectly flat, the electrical contact is not formed over their entire surface. This gives rise to several drawbacks.

The defects in flatness or the difference in length may be such that contact between a conducting element and its counterpart is not achieved, and the connection is then defective.

The defects may be less significant than in the preceding case, the electrical contact between the conducting element and its counterpart then being formed with a contact area less than the contact area of the conducting elements. Two phenomena may then occur.

In general, the area of contact between these elements is calculated as a function of the strength of the current so that the connection element does not heat up too much. The defect in flatness thus entails overheating of the connection element. Moreover, the parts of the contact surfaces which are not in contact are separated by a thin layer of air which is very slightly conducting, and there exists a risk that an electric arc will be formed in the layer of air.

These two phenomena may, in certain cases, set fire to the connection element as well as to its surroundings.

It is an object of the present invention to at least partly mitigate the difficulties of the prior art.

According to the present invention there is provided a connector for forming an electrical connection between a first upper and a second lower subassembly, the first subassembly including a housing having at least two first electrically conducting contact elements passing through a lower wall of the housing, the second subassembly including at least two second conducting contact elements which are fixed onto a support and which are intended to be put into electrical contact with the first two conducting contact elements, the housing and the support including assembly means able to exert a contact pressure between corresponding surfaces of the first and second conducting contact elements, wherein the first conducting contact elements are moveable in axial translation in the housing, and wherein means, elastically deformable in the direction of the contact pressure exerted by the assembly means, are disposed between the housing and the second conducting contact elements in such a way that:

when the two subassemblies are assembled, the corresponding surfaces of the conducting elements are in contact; and the contact pressure is distributed substantially uniformly over the corresponding surfaces of the first and second conducting contact elements.

According to other characteristics of the invention:

- the elastic means are an elastic washer, and the first electrically conducting contact elements are axially parallel and are arranged in a ring; - the assembly means pass axially through the elastic washer; - the assembly means are a single screw, the lower transverse surface of the upper head of which bears on a cap for closing the housing and the threaded lower free end of which interacts with a complementary tapping situated in the second subassembly; - the cap of the housing is electrically conducting, and the assembly means electrically link the electrical earth of the first and of the second subassemblies by contact, on the one hand, with the electrical earth of the second subassembly and, on the other hand, with the conducting cap of the housing which is itself in contact with the electrical earth of the first subassembly; - each of the first conducting contact elements includes a contact part which is guided axially in the housing and a lower end of which is put into contact with one of the second conducting contact elements, and includes a transverse part which allows it to be connected electrically with at least one conducting 5 wire of an electrical cable; - the upper face of the housing, delimited by the upper edge of the housing, is open so as to make it possible to arrange inside it, successively from bottom to top:

the first conducting contact elements which are arranged in a ring and which project downwards out of the housing through orifices produced in the lower wall of the housing; 0 and the elastic washer which bears on the upper bearing faces of the first conducting contact elements; and the cap is fixed onto the upper edge of the housing, especially by crimping, so as to close the said open face; - the assembly means include a shouldered part made of an electrically conducting material and passing axially through the housing, as well as the arrangement of the first conducting contact elements and the elastic washer and, upon assembly of the two 2S subassemblies, the shouldered part of the assembly means bears on the conducting cap, so as to ensure electrical contact between the cap and theassembling screw, and in order axially to compress the elastic washer.

An exemplary embodiment will now be described with reference to the accompanying drawings, in which:

- Figure I shows an exploded perspective view of an embodiment of an electrical connector according to the invention; - Figure 2 shows a cross-sectional view of an embodiment of an electrical connector according to the invention, the section being taken along the line 2-2 of Figure 3, and in assembled position of the two subassemblies; - Figure 3 represents a top view, along the arrow F3 of Figure 4, of the first subassembly of the connector of Figure 1, illustrated without its closure cap; - Figure 4 represents the view in longitudinal section along the line 4-4 of Figure 3, of the first is subassembly, with the closure cap; - Figure 5 represents a view on a larger scale, in cross section, of the rear part of the first subassembly; - Figure 6 represents a top view on a larger scale of the second subassembly of the connector of Figure 1; - Figure 7 is a partial view in axial section showing a variant of the assembly means equipped with a knurling. 25 In the various figures, like reference numerals refer to like parts. In the description, an orientation from front to rear and upper and lower will be used; this corresponds to the orientation from left to right and top and bottom in accordance with Figure 1 and 4.

In Figures 1 to 4 an embodiment of a connector 10 is shown, which consists of a first, upper subassembly 12 linked to a shielded electrical cable 14, and of a second, lower subassembly 16 linked to the rotor 18 of a rotating electric machine 20, for example a motor-vehicle alternator, which in a variant may be reversible and operate as an electric motor for starting the motor vehicle. Such an alternator is called alternator-starter.

The first, upper subassembly 12 includes a housing 22 made of electrically insulating material which is of substantially rectangular parallelepipedal shape.

The housing 22 is hollow and it consists of a pierced, flat horizontal lower wall 24 as well as of three vertical sidewalls 26, 28 and 30. One wall, at the front of the housing 22, is a transverse front wall 28, the other two being opposed longitudinal walls 26 and 30. The upper faces of the sidewalls 26, 28 and 30 define the upper edge of the housing. The upper face of the housing, delimited by the upper edge of the housing, is open and it is closed by an affixed metal cap 32 in the general shape of a plate bearing on the upper edge of the housing 22.

The cap 32 is in contact with the earth of the first subassembly.

Advantageously, the housing 22 is produced by moulding from plastic.

The housing 22 includes, along its length, a front part intended to interact with the second, upper subassembly 12 and a rear part allowing for mechanical fixing of the electrical cable 14 into the housing 22.

The cable 14 here includes four electrical wires 37, each consisting of an electrically conducting element 36 surrounded by an electrically insulating sheath 38, which are surrounded by a metal braid 34 for electromagnetic screening of the electrical cable 14.

The front part is configured about a vertical 5 assembly axis A.

The housing 22 exhibits general design symmetry with respect to a median longitudinal vertical plane corresponding to the line 4-4 of Figure 3.

Five orifices, in the form of cutouts, are formed in the front part of the lower wall 24 constituting the bottom of the housing 22.

Four of them, referenced 42 in Figure 1, are identical. They have the shape of an annular sector and are arranged regularly in the adjacent sectors around the fifth central cut-out 44 of circular shape which is centred on the assembly axis A. The four cutouts 42 allow for translational guidance of four contact blocks 82 of four first electrically conducting contact elements 80.

In the vicinity of the five cutouts 42 and 44, a tube 48, as well as four partitions 60, 62, 64 and 66 extend in projection vertically upwards so as to form the axial guidance in translation and the electrical insulation of the four contact blocks 82. The tube 48 thus internally delimits the central cutout 44 and externally delimits the cutouts 42.

A skirt 46 extends in vertical projection (axially with respect to the axis A) downwards, from the outer face of the lower wall 24 near the bottom of the housing 22. It is of tubular shape with axis A. It has an internal diameter greater than the external diameter of the ring partially defined by the four annular sectors of the cutouts 42. It serves for guidance when assembling the first 12 and the second 16 subassemblies as will be explained later.

Within the housing 22, the tube 48, with axis A, S extends axially, that is to say vertically, upwards, from the lower wall 24 up to the upper edge of the housing 22. The tube 48 is produced by moulding with the housing 22 and it is intended to be traversed centrally by the body of an assembly screw 50.

Its internal diameter corresponds to the diameter of the central cutout 44 and its outer cylindrical surface 49 delimits, radially inwards and vertically upwards, the ring partially defined by the four cutouts 42.

The four vertical partitions moulded with the housing 22 are distributed regularly and radially about the tube 48. Two of them, 60 and 62, extend transversely in opposing fashion over a width substantially equal to the width of the sectors of the ring defined by the four cutouts 42.

The other two partitions 64 and 66 extend longitudinally in opposing fashion in the median plane of the housing 22. The partition 64 extends longitudinally forwards over a length which is equal to the distance which separates the extreme cylindrical surface 49 of the tube 48 at the wall 28 so as to link them, and the partition 66 extends longitudinally rearwards over a greater length.

The partitions 60, 62 and 64 have the same defined height, which is less than the height of the walls of the housing 22. The upper face of the partition 66 is stepped, and includes a front upper face 67 the height of which is equal to thedefined height of the other three partitions. The height of the upper rear face 69 of the rear part is equal to that of the upper edge of the housing 22.

The defined height of the partitions 60 to 66 makes it possible to arrange an elastic washer 70, delimited by a lower horizontal annular face 72 and an upper horizontal annular face 74, and which is mounted axially in the housing 22 on the radial upper faces 61, 63 and 65 of the partitions 60, 62 and 64, as well as on the upper face 67 of the front part of the partition 66.

The upper face 69 of the rear part of the partition 66 of greater height includes a stud 68 which allows the cap 32 to be put in position subsequently and fixed.

The front part of the housing 22 is intended to accommodate the first four electrically conducting elements 80 which each consist of two parts made of electrically conducting material. A first contact part is a contact block 82 which comprises a lower, contact face 83 and an upper bearing face 85.

The lower, contact face 83 makes it possible to form the electrical connection with the second, lower subassembly 16. The upper face 85 serves as a seat for the elastic washer 70 pushing on the blocks 82 which are guided by the tube 48. A second, linking part is transverse and here consists of a linking lug 84 which allows for fixing and electrical connection with an associated wire of the wires 37 of the electrical cable.

The first conducting elements 80 are symmetric pairwise with respect to a median plane of the housing 22. They are thus identical pairwise which reduces the costs of production.

Each contact blocks 82 consists of a vertical bar shaped as a section of tube with cross section in the shape of an annular section which is very slightly less than the cross section of the four cut-outs 42.

However, the area of the cross section of the contact blocks 82 has to be greater than a minimum cross section. This is because the passage of a current in an electrical conductor causes heating of the conducting material, by Joule effect, which is proportional to the product of the resistance of the conducting material and the square of the strength of the current. It is therefore necessary for the cross section of the contact blocks 82 to be greater than the minimum cross section for which the temperature of the contact blocks 82 reaches a temperature which would risk setting fire to the connector 10 or a temperature equal to the melting temperature of the contact blocks 82.

The determination of the height of the blocks 82 will be explained in the remainder of the description.

The linking lugs 84 are of substantially parallelepipedal shape, with a transverse face which is complementary to the cylindrical-arc-shaped, axially oriented convex outer face 87 of the contact blocks 82.

The linking lugs 84 are situated at the upper part of the contact blocks 82.

They each include two piercings which are perpendicular to one another and which have a diameter allowing the conducting elements 36 of the cable 14 to pass through. One of the piercings opens out transversely to the linking tab 84, the other is longitudinal to the linking tab 84 and is blind at its extremity adjacent to the contact blocks 82.

The presence of the two piercings makes it possible to standardise the lugs 84, only one of the two piercings being used in the way described below.

Advantageously, each first conducting element 82 in two parts is produced in a single piece.

The first conducting elements 80 project downwards out of the housing 22 through the cut-out shaped orifices 42 and are moveable in axial translation, that is to say vertically, in the housing 22 while being axially parallel and configured in a ring.

Each first conducting element 80 makes it possible to link one electrical phase of the second, lower subassembly 16 electrically to an electrically conducting element 36 of the electrical cable 14.

In its rear part, the housing 22 includes means for fixing the electrical cable 14.

The free rear end 86 of the housing 22,which can be seen in section in Figure 5, is a generally "U" shaped retaining part 88. The internal diameter of the retaining part 88 corresponds substantially to the external diameter of the screening braid 34 of the electrical cable 14.

Spigots 90 are arranged on the inner surface of the retaining part 88; they are configured radially into three parallel rows and they make it possible, when the electrical cable 14 is put in place in the retaining part 88 of the housing 22, to prevent any longitudinal slipping of the electrical cable 14 with respect to the housing 22.

Moreover, two holes 92 and 94 are formed in the free rear extremity 86 and, more particularly, in the thickness of the longitudinal walls 26 and 30 respectively. The two holes 92 and 94 are vertical, parallel to the assembly axis A, and open out upwards and downwards. They are intended to accommodate mounting screws 96 and 98 respectively in interaction with nuts 100 and 102.

The open upper face of the housing 22 is closed by the cap 32 which is obtained by stamping from a plate of substantially rectangular shape, and which includes various vertical orifices among which can be distinguished:

- through holes 120 which are situated at the periphery and at the centre of the cap 32; these are intended to accommodate studs 122 and 68 placed on the upper faces of the vertical walls 26, 28 and 30, as well as on the rear upper face 69 of the rear part of the partition 66, so as to position the cap 38; - two piercings 124 and 126 which are formed at the rear of the cap 32, and which allow the mounting screws 96 and 98 to pass through; 25 - and a piercing 128 which is situated in the front part of the cap 32 so as to allow the body of the assembly screw 52 to pass through when the connector 10 is assembled. The free rear end 130 of the cap 32 features a narrowing as well as a longitudinal corrugation which makes it possible to match closely to the screening braid 34 of the electrical cable 14 and to clamp it radially, when the housing 22 is closed in accordance with the sectional view of Figure 5.

The assembling of the first, upper subassembly 12 is as follows.

In the first place, it is necessary to prepare the electrical cable 14. A free end part of the metal screening braid 34 is removed, so as to leave the four electrical wires 37 free over a given length. The free length of each electrical wire 37 is adjusted so as to be able to carry out the subsequent fitting in the housing 22.

Next, the free end of each electrically conducting element 34 is bared and it is inserted into one of the two piercings of one of the linking lugs 84.

The choice of the orientation of the piercing into which the bared free end of the conducting element 34 is inserted depends on the position and on the orientation of the linking lug 84 in question.

In the case of the first two conducting elements 80 situated at the front of the tube 48, the free end of the conducting element 34 is inserted into the transverse piercing of the linking lug 84. Conversely, for the first two conducting elements 80 situated at the rear of the tube 48, the free end of the conducting element 34 is inserted into the longitudinal piercing of the linking lug 84. Thus, after fitting, the four electrical wires 37 are oriented longitudinally in the housing 22.

An operation of crimping of the free end of the conducting elements 34 in the piercings of the linking lugs 84 is then carried out.

- is - The first four conducting elements 80 are then inserted vertically from the top downwards into the cutouts 42. The conducting elements 80 are free in axial translation along the axis A, but the linking lugs 84 as well as the electrical wires 37 which are secured to them prevent them from falling below an initial position, that is to say before assembling of the two subassemblies, called rest position. In this position, the upper support faces 85 of the first four conducting elements 80 have to be at a height which is preferably slightly less than that of the radial upper faces 61, 63, 65 and 67 of the partitions 62, 64, 65 and 68 respectively.

Next, the elastic washer 70 is positioned around the tube 48, with its lower annular face 72 which is then bearing on the radial upper faces 61, 63, 65 and 67. The cap 32 is then put in place supported vertically on the upper edges of the side walls 26, 28 20 and 30 in such a way that the studs 122 as well as the stud 68 pass through the complementary piercings 120. In this configuration, a clearance il preferably exists between the upper annular face 74 of the elastic washer 70 and the opposing portion of the lower face of the cap 32, and the elastic washer 70 is therefore not compressed axially. The studs 122 and 68 are then crimped, here while hot, so as to immobilise the cap 32 onto the housing 22.

The mounting screws 96 and 98 are then inserted from the bottom upwards into the holes 92, 94 and into the piercings 124, 126 of the cap 32, then the nuts 100 and 102 are screwed, so as to clamp the electrical cable 14 radially between the spigots 90 of the free rear end 86 of the housing 22 and the free rear end of the cap 32.

Advantageously, a heat-shrinking sheath 132 is arranged around the free rear end 86 of the first, upper subassembly 12, as well as around the part of the screening braid 34 of the electrical cable 14 coming out of the first subassembly 12. After heating, the heat- shrinking sheath 132 ensures good leaktightness between the electrical cable 14 and the first subassembly 12.

The second, lower subassembly 16 which is intended to be coupled with the first, upper subassembly 12 is fixed onto the rotating machine 20.

it consists principally of four second electrically conducting contact elements 150 called conducting "tracks" which are metal strips cut out and embedded in the electrically insulating material of a moulded support 152, and of a tapped metal insert 154.

These strips are linked, for example to facilities for connection to the conductors of the stator of the machine as described in the document FR-A2 754 650.

The support 152 is integral with the outer wall of the rotating machine 20, for example by the use of screws which are not visible. It is of electrically insulating material and is overmoulded around four second electrically conducting contact elements 150. The overmoulding of the four second conducting contact elements 150 allows, on the one hand, the electrical insulation of each of the said conducting elements 150 with respect to one another and, on the other hand, excellent resistance to the vibration of these same conducting elements 150.

The electrically insulating support 152 is arranged around the assembly axis A which here is of radial orientation with respect to the axis of rotation of the rotating machine 20.

The support 152 features design symmetry with respect to a median longitudinal vertical plane corresponding to the line L of Figure 6.

The upper part 156 of the support 152 consists principally of two concentric tubular parts 158, 160 which have, as axis of revolution, the assembly axis A and which are linked by four radial partitions 157.

The four partitions 157 are arranged regularly is in such a way as to create four adjacent annular sectors 159 the cross section of which is similar to that of the cutouts 42 of the first subassembly 12.

The first tubular part is a skirt 158 which extends in projection axially upwards from the support 152, that is to say vertically. Its external diameter is substantially less than the internal diameter of the skirt 46 of the first subassembly 12.

When the two subassemblies 12 and 16 are assembled, the skirt 46 of the housing 22 comes to cover over the skirt 158. The internal diameter of the skirt 158 is substantially greater than the diameter of the cylinder defined by the convex outer faces 87 of the first four conducting contact elements 80 when they are mounted into the housing 22. These latter coming, when the connector 10 is assembled, to be fitted closely into the adjacent annular sectors 159 defined by the partitions 157 in the inner cylindrical part of the skirt 158.

The second tubular part is a tube 160 with axis A which extends projecting axially upwards, that is to say vertically, up to the upper edge of the skirt 158.

The tube 160 is produced by moulding the support 152 and it is intended to be traversed by the body of the electrically conducting assembly screw 50 as well as the cap of the housing 22. Its internal and external diameters correspond to the internal and external diameters of the tube 48 of the housing 22.

The upper faces, or edges, of the skirt 158 and of the tube 160 are situated in the same horizontal plane. Their height will be defined later.

A lower part 164 of the support 152 is a block which includes an upper face 162 parallel to a lower face 163. A cutout 166 is formed in the lower face 163 and extends upwards. The cutout 166 makes it possible to make the thickness of the lower part 164 uniform.

This is because, with the support 152 being produced by moulding, care has to be taken that the differences in thickness are a minimum so that, while it is being manufactured and more precisely while it is being cooled, there is no formation of hot spots which are at the origin of defects such as cracks.

Moreover, the cutout 166 makes it possible to form a space intended to accommodate an electrically conducting tapped metal insert 154.

The axis of the tapping of the metal insert 154 corresponds to the assembly axis A. The height of the tapped metal insert 154 is substantially equal to the height of the cutout 166 so as not to project from the 19 - lower face 163 of the lower part 164, in such a way as to minimise the overall size of the second subassembly 16.

The four second conducting contact elements 150 are moulded in the lower part 164. Their lower end is situated in the bottom part of the lower part 164. Each end is designed so as to be linked electrically to one phase 168 of a winding of the coil of the rotating machine 20.

The orientation of the lower ends of the second conducting contact elements 150 makes it possible to bring these latter close to the windings of the coil of the rotating machine 20 and thus to minimise the length of the outlet for the phases 168.

The four second conducting contact elements 150 are electrically insulated from one another by the moulded insulating material of the support 152. They each have an active upper horizontal contact surface 172 which comes flush with the support, in the space situated between the skirt 158 and the tube 160. The active surfaces 172 are the counterparts of the lower contact faces 83 of the contact blocks 82. The assembly of the first 12 and of the second 16 subassemblies is as

follows.

once the first, upper subassembly 12 has been assembled, its skirt 46 comes to cover over the skirt 158 of the second, lower subassembly 16 via a translational movement from the top downwards until the lower contact faces 83 of the first conducting elements 80 come into contact with the active surfaces 172. At that moment, the first conducting contact elements 80 are immobile with respect to the second subassembly 16, the translational movement is continued in such a way that the lower face of the cap 32 comes into contact with the upper annular face 74 of the elastic washer 70 since the said lower face compresses the elastic washer.

The translation of the first, upper subassembly 12 is terminated when the lower face of the housing 22 is in contact with the upper edge of the skirt 158.

The first 12 and second 16 subassemblies are then in a position known as "assembled" position.

Hence, the force resulting from the compression of the elastic washer 70 is distributed substantially uniformly over the upper bearing faces of the first four conducting elements 80, which causes a virtually constant pressure in the region of the contact between the lower contact faces 83 and the active surfaces 172.

In order to reach the assembled position, two dimensional conditions have to be fulfilled.

The first is the existence of a clearance J2 between the lower end face of the skirt 46 and the upper face 162 of the lower part 164 of the support 152.

The second is that the height of the contact blocks 82 is such that each free lower end face of the contact block 82 is in contact with an active surface 172 and that the free upper end face of each contact blocks 82 is subjected to a downwards axial force resulting from the local elastic compression of the washer 70.

However, it is necessary for the first 12 and the second 16 subassemblies to be in a correct angular position, that is to say that the phase of the rotor 18 of the rotating machine 20 which has to be linked to an element in electrical contact with a wire 37 of the cable 14, be linked to the active surface 172 which is in contact with the first conducting element 80 onto 5 which the said wire 37 is crimped.

The angular position of the first 12 and second 16 subassemblies is correct when the median plane of the housing 22 and the median plane of the support 152 are coincident. The angular position of the first 12 and of the second 16 subassemblies is then such that each lower contact face 83 of the contact blocks 82 is in contact exclusively with the corresponding active surface 172. To do that, the skirts 46 and 158 include a female indexing device 174 and a male indexing device 176 respectively, of the same height. The female indexing device 174 consists of a semi-cylindrical female indentation or groove, formed in the thickness of the front part of the skirt 46, at the intersection of the skirt 46 and of the first median plane. The male indexing device 176 consists of a semi-cylindrical male rib, produced on the external diameter of the front part of the skirt 158, at the intersection of the skirt 158 and of the second median plane.

This male indexing device 176 is intended to penetrate in a complementary way into the female indexing device 174.

A seal 178, the thickness of which is greater than the clearance J2, is arranged between the lower end face of the skirt 46 and the upper face of the lower part 164 of the support 152 so as to ensure the leaktightness of the connector 10.

In a variant (not represented) the seal 178 is replaced by means forming a labyrinth.

The second dimensional condition makes it possible to guarantee the elastic compression of the washer 70 which, in addition to distributing the clamping forces substantially uniformly in the region of the four contact interfaces between the lower contact faces 83 of the contact blocks 82 and the active surfaces 172, also makes it possible to compensate for the defects in flatness of the lower contact faces 83 of the contact blocks 82 or the differences in height of the contact blocks 82.

The assembly screw 50, of axial orientation, passes axially through the cap 32, the elastic washer 70, the tubes 48 and 160 of the housing 22 and of the support 152 respectively, and it is screwed into the tapped metal insert 154. The head of the assembly screw 50 bears on the upper face of the cap 32. The face of the free upper end of the tapped metal insert 154 comes to bear on the upper face of the cutout 166. A clamping torque is applied in such a way that the first, upper subassembly 12 is held onto the second, lower subassembly 16 and that an axial clamping force is applied at the contact interfaces between the free end faces of the contact blocks 82 and the active surfaces 172. Advantageously, other assembly means, such as a fixing clipped by elastic interlocking can replace the assembly screw 50. 30 In a variant, the assembly means consist of a rivet, a head of which bears on the cap 32 and the body - 23 passes through the cap, the tubes 48, 160 and the metal insert 152, which may therefore not be threaded.

The arrangement thus exhibits the advantage of not being sensitive to vibration. This is because the free lower end faces of the contact blocks 82 and the active surfaces 172 are held in contact by an elastic washer 70 which absorbs the slight deformations due to vibration.

Moreover, the connector 10 is identical, whether the coupling of the rotating machine 20 is in star or delta mode. This makes it possible to standardise the moulds for manufacturing the housing 22, and the support 152 as well as the dies for the cap 32.

Advantageously, the electrical earth of the is rotating machine 20 is linked to the tapped metal insert 154 which is electrically conducting as well as the assembly screw 50 and the cap 32 which makes it possible, after the assembly of the first 12 and of the second 16 subassemblies, to provide electrical continuity from the electrical earth of the rotating machine 20 onto the screening 34 of the electrical cable 14.

Forming the electrical contact for the earth of the rotating machine 20 thus does not require any supplementary element, which reduces the costs and the overall size of the connector 10.

In the configuration in which two electric machines are linked by one electrical cable and a connector 10, it is then possible to link the electrical earths of the two electric machines which curbs any electromagnetic interference.

The preceding description is not a limitation on the invention.

In fact embodiments of the invention find application in a connector including "n" first 80 and second 150 conducting elements. For a given overall size, the number "n" of conducting elements is limited by the dimensions of the cross section of each of them. This is because the said cross section has to be greater than the minimum cross section which is defined above.

The geometric compactness of the connector will be appreciated, which makes it possible to minimise the length of the phase outlets for the rotor 18 belonging, in the case of an alternator or of an alternatorstarter, to the stator of the rotating machine.

This stator is, in a known way, carried by a pierced casing including a front bearing and a rear bearing carrying a rotary shaft integral with the rotor of the machine surrounded by the stator. The shaft passes through the front bearing in order to carry a drive pulley.

Embodiments of the connector may be carried externally by the rear bearing of the machine constituting the abovementioned outer wall of the rotating machine.

In a variant, the connector is carried by the front bearing. The control and regulation electronics for the alternator are, in one embodiment, carried by the rear bearing.

In a variant, particularly when an alternator starter is involved, these electronics are carried by a fixed housing separate from the alternator. In this - 2S - case, the embodiment of the connector is carried by the fixed housing. The lower subassembly may belong to a regulation subassembly described, for example, in the document FR5 A-2 754 650. For preference, the housing 22 and the support 152 are made of mouldable plastic reinforced by fibres, such as glass fibres. The presence of a single assembly means will be appreciated, here the screw 50, between the casing 22 and the support 152.

This assembly item, here electrically conducting, allows a uniform distribution of pressure on the contact blocks 82 of the first electrically conducting elements 80.

The assembly item thus carries out three functions.

The tube 48 carries out a double function, namely the passage of the assembly item with electrical insulation and the guidance of the blocks.

The presence of the cutouts 42 is made possible by virtue of the electrically insulating partitions 60, 62, 64, and 65 making it possible to guide and separate the first elements 80 from one another while ensuring good mechanical behaviour of the tube 48. These partitions are therefore partitions for stiffening the housing 22, allowing for the presence of the cutouts 42 and a linking of the tube with the front wall 28 and the lower wall 24 of the housing.

As will have been understood, the washer 70 is advantageously made of plastic, such as an elastomer.

The metal insert 154 is not necessarily tapped, particularly when the assembly means consists of rivets or of the clipped fixing. The metal insert may belong to the assembly rivets, the head of which is deformed 5 in contact with the cap.

In this case the connector cannot be dismantled. The solution with the screw is preferable since the clamping can be better controlled.

obviously, the structures can be inverted. Hence the head of the screw is, in a variant, carried by the support 152 of the second subassembly, the body of the screw passing through the tubes 160, 48 and the cap. An assembly nut is screwed onto the free end of the screw. This nut bears on the upper face of the cap indirectly by means of a bearing washer through which the screw passes.

Advantageously the screw is knurled in the region of its lower head, in such a way that the screw can be inserted forcibly by its knurling into the insert 154, which is then not tapped, and thus be kept captive.

In a variant, the insert 154 is replaced by a column moulded integrally with the support 152.

The lower head of the screw bears on the free end of the column, and passes through it with its body as well as the tubes 160, 48, the cap 32 and a bearing washer such as a Grower washer or a Belleville washer.

The assembly nut is screwed onto the free end of the screw in contact with the bearing washer and flattens this bearing washer in contact with the upper face of the cap. Clearly, the screw exhibits a knurling in the vicinity of its head for anchoring it into the column. This column, forming a boss, may come out from the abovementioned outer wall of the rotating electrical machine as can be seen at 200 in Figure 7. In this case, the support 152 bears on the free end of the column 200, with a stepped internal bore in order to form a shouldering for the lower head 201 of the screw 50, the knurling of which can be seen at 202 forcibly engaged into the portion of smallest internal diameter of the column 200 in such a way that the screw 50 is kept captive.

In a variant, the nut can be soldered onto the upper face of the cap and the screw head bears directly or indirectly on the support in order to be screwed onto the nut.

In all cases, the electrically conducting assembly means include a shouldered part such as a head or a nut, bearing on the cap, and a body passing through the housing and thus the first conducting elements and the elastic washer.

Claims (20)

1. A connector for forming an electrical connection between a first upper and a second lower subassembly, the first subassembly including a housing having at least two first electrically conducting contact elements passing through a lower wall of the housing, the second subassembly including at least two second conducting contact elements which are fixed onto a support and which are intended to be put into electrical contact with the first two conducting contact elements, the housing and the support including assembly means able to exert a contact pressure between corresponding surfaces of the first and second conducting contact elements, wherein the first conducting contact elements are moveable in axial translation in the housing, and wherein means, elastically deformable in the direction of the contact pressure exerted by the assembly means, are disposed between the housing and the second conducting contact elements in such a way that:

   when the two subassemblies are assembled, the corresponding surfaces of the conducting elements are in contact; and the contact pressure is distributed substantially uniformly over the corresponding surfaces of the first and second conducting contact elements.
2. 2. The connector of claim 1, wherein the elastically deformable means are an elastic washer, and the first conducting contact elements are axially parallel and are arranged in a ring.
3. 3. The connector of claim 1 or 2, wherein the assembly means pass axially through the elastic washer.
4. 4. The connector of any preceding claim, wherein the assembly means are a single screw with axial orientation, the lower transverse surface of the upper head of which bears on a cap for closing the housing and the threaded lower free end of which interacts with a complementary tapping situated in the second subassembly.
5. 5. The connector according to any one of the preceding claims, wherein the housing is electrically insulating and is closed by a cap, the cap of the housing is electrically conducting, and the assembly means electrically link the electrical earth of the first and of the second subassemblies by contact, on the one hand, with the electrical earth of the second subassembly and, on the other hand, with the conducting cap of the housing which is itself in contact with the electrical earth of the first subassembly.
6. 6. The connector according to any one of the preceding claims, wherein each of the first conducting contact elements includes a contact part which is guided axially in the housing and a lower end of which is put into contact with one of the second conducting contact elements, and includes a transverse part which allows it to be connected electrically with at least one conducting wire of an electrical cable.
7. 7. The connector of claim 5, wherein the upper face of the housing, delimited by the upper edge of the housing, is open so as to make it possible to arrange inside it, successively from bottom to top: 5 - the first conducting contact elements which are arranged in a ring and which project downwards out of the housing through orifices produced in the lower wall of the housing; - and the elastic washer which bears on the upper bearing faces of the first conducting contact elements; and wherein the cap is fixed onto the upper edge of the housing, especially by crimping, so as to close the said open face.
8. 8. The connector according to Claim 7, wherein the assembly means are electrically conducting and include a shouldered part and a body, and in that the body of the assembly means passes axially through the housing, as well as the arrangement of the first conducting contact elements and the elastic washer, and wherein, upon assembly of the two subassemblies, the shouldered part of the assembly means bears on the conducting cap, so as to ensure electrical contact between the cap and the assembly means, and in order axially to compress the elastic washer.
9. 9. The connector according to Claim 8, wherein the orifices are delimited by a tube extending inside the housing upwards from the lower wall as far as the upper face of the housing and wherein the assembly means pass through the tube.
10. 10. The connector according to Claim 9, wherein partitions are distributed around the tube in order to guide the first conducting contact elements.
11. 11. The connector of Claim 8 or 9, wherein the housing features a skirt of tubular shape extending from the lower wall of the housing, downwards from the housing in order to serve as guidance when assembling the first and second subassemblies.
12. 12. The connector according to any one of Claims 7 to 11, wherein the support of the second, lower subassembly includes an upper part including two concentric tubular parts which are linked by radial partitions in order to create adjacent annular sectors the cross section of which is similar to that of the orifices of the housing of the upper subassembly, in such a way that the first conducting elements come to be fitted into the adjacent annular sectors when the connector is assembled.
13. 13. The connector according to Claim 12, wherein the first tubular part is a skirt which extends upwards from the support and which is of slightly smaller external diameter than the internal diameter of the skirt of the first, upper subassembly.
14. 14. The connector of Claim 13, wherein the second tubular part is a tube intended to be traversed by the body of the assembly means and which extends upwards from the support, and wherein the internal and external diameters of the said tube correspond to the internal and external diameters of the tube of the housing.
15. 15. The connector according to Claim 13 or 14, wherein the skirts of the housing and of the support include a female indexing device and a male indexing device respectively for a correct angular position of the first and second subassemblies when the median plane of the housing and the median plane of the support are coincident.
16. 16. The connector according to Claim 15, wherein the female and male indexing devices have the same height and in that the female indexing device consists of a semi-cylindrical groove and the male indexing device of a semi- cylindrical rib.
17. 17. The connector according to any one of the preceding claims, wherein the support of the second subassembly is of electrically insulating material and is overmoulded around the second conducting contact elements.
18. 18. The connector according to Claim 17 when dependent on claim 12, wherein the second conducting contact elements each have an active upper contact surface which comes flush with the support in the space situated between the skirt and the tube of the second subassembly.
19. 19. The connector according to any one of the preceding claims taken in combination with Claim 4, $I wherein the assembly means consist of an electrically conducting screw screwed into a metal insert belonging to the second, lower subassembly.
20. 20. The connector according to any one of the preceding claims, and including four first conducting contact elements and four second conducting contact elements, regularly distributed.