Connection assembly having multi-contact connectors with a polarizing system using keys

A connection assembly includes a first connector and a second connector, each with a housing extending along an axis and having a connection face, being connected together via their connection faces. Also included is, at least, one coupled-together pair of polarizing keys, each key being of elongate shape along an axis and projecting from one of the housings beyond its connection face. Each key includes at each one of its ends a portion with a peripheral surface that is provided with at least one projecting and/or hollow shape. Each end portion of one of the two keys is adapted to engage via complementary shapes with a single end portion of the other of the two keys along their coinciding axes and in only one relative angular position between them. Each polarizing key is fastened via one of its end portions to the housing of one of the connectors.

FIELD OF THE INVENTION

The present invention provides a connection assembly comprising multi-contact connectors that are connected together and polarizing keys that enable only the desired connection to be made.

BACKGROUND OF THE INVENTION

Patent application EP 1 708 313 in the name of the Applicant discloses a connection assembly comprising a first multi-contact connector and a second multi-contact connector of complementary type. Each connector comprises a housing receiving contacts, and the connection assembly includes a cap enabling the first and second connectors to be locked together.

Another known connection assembly comprising multi-contact connectors is sold by the Applicant under the trade name Amphenol-Air LB—Series 1900. In that connection assembly, in addition to mechanical and electrical connection that is provided via their connection faces, mechanical coupling between the connectors is also provided via polarizing keys in the form of screws F1 and M1 having hexagonal heads in which the end portion is either a tongue or a corresponding slot. A screw with a hexagonal head projects from each of the two lateral ends of the housing of the male connector and from each of the two lateral ends of the housing of the female connector. Each screw head includes a notch constituted by a flat of the hexagon and constituting a first visual coding mark. At each of its two lateral ends, each housing is marked close to the complementary hexagonal recess for a screw head with a second visual coding mark in the form of a letter A or B, and above each flat of the hexagonal recess with a third visual coding mark in the form of successive digits 1 to 6. Thus, in order to perform coding with the four polarizing keys in the form of screws, each of them is inserted in a complementary hexagonal recess in a lateral end of a housing while causing the first visual coding identifier, i.e. the notch of the screw head to corresponding with the second and third visual coding identifiers, namely the letter A or B and one of the digits 1 to 6. Such a polarizing system with four polarizing keys distributed individually on each lateral end of a male or female connector housing is advantageous since it enables polarizing coding to be performed with up to 36 combinations. Nevertheless, it is not completely satisfactory, since it allows the codes to be viewed only from the rear faces of the housings, and above all it always requires an extractor tool to be used in order to remove the polarizing keys from their recesses. When snap-fastened in a connector housing, a polarizing key can be removed only from beside the coupling face (where the connectors couple together), and necessarily by applying pressure with an extractor tool.

The inventors have sought to have a connection assembly as described above and sold under the trade name Amphenol-Air LB—Series 1900, but that is also fitted with a cap that slides on one of the housings so as to enable the two multi-contact connectors to be locked together, e.g. such as the cap described in European patent application EP 1 708 313. Unfortunately, in its unlocked position, such a cap must come into register with one of the lateral ends of the housings, thus making it impossible to provide polarizing at that lateral end by using screws as provided in the commercially available assembly. In other words, the inventors have come to the conclusion that improving the commercially-available connection assembly by providing it with a cap for locking the connectors together implies having keying at only one of the two lateral ends of the housings. However, by retaining the polarizing by means of screws as is presently performed and as described above also implies making do with coding having a number of combinations that is limited, being equal to six.

There therefore exists a need to improve a connection assembly comprising two complementary connectors, in particular multi-contact connectors, such as the assembly sold under the trade name Amphenol-Air LB—Series 1900, in particular in order to fit it with a cap for locking the connectors together and with a polarizing system at only one lateral end, but with the possibility of coding on a large number of combinations.

There also exists a need to eliminate the use of a tool when removing a polarizing key from a housing of a connector, in particular a multi-contact connector.

OBJECT AND SUMMARY OF THE INVENTION

An object of the present invention is to satisfy the above-mentioned needs in full or in part.

In exemplary embodiments the invention achieves this object with the help of a connection assembly comprising:a first connector, in particular a multi-contact connector;a second connector, in particular a multi-contact connector, of type complementary to the first connector, the first and second connectors each comprising a housing extending along an axis and having a connection face, the first and second connectors being connected together via their connection faces; andat least one coupled-together pair of two polarizing keys, each key being of elongate shape along an axis and projecting from one of the housings beyond its connection face;

wherein each key includes at each one of its ends a portion with a peripheral surface that is provided with at least one projecting and/or hollow shape, by the fact that each end portion of one of the two keys is adapted to engage via complementary shapes with a single end portion of the other of the two keys along their coinciding axes (X1=X2) and in only one relative angular position between them, and by the fact that each polarizing key is adapted to be fastened via one or the other of its end portions to the housing of the first and/or the second connector in a plurality of given angular positions relative to the axis.

Because both of the polarizing keys can be engaged reversibly, i.e. via either end portion, the invention thus makes it possible to double the number of coding combinations in a single zone of the connection assembly.

Thus, by means of the invention, it is possible to propose a connection assembly having multi-contact connectors with a large number of coding combinations, while also providing it with a cap for locking the connectors together, the cap being slidably mounted on one of the connector housings.

In exemplary embodiments, each key projects from only one of the lateral ends of a housing beyond the connection face of the housing.

In order to identify the coding easily, it is advantageous to provide for one end portion of a key to include at its end or on its outer periphery a first visual indicator that is distinct from the visual indicator of the other end portion of the same key, each first visual indicator being visible from outside the housing when the corresponding key is fastened in the housing. Advantageously, the end portion of one of the two keys of the pair has the same first visual indicator as the end portion of the other one of the two keys of the pair with which it is adapted to engage.

Preferably, the first visual indicators are letters (A, B).

According to advantageous characteristics, the first visual indicators are made by marking the keys. Preferably, the marking results from a shape made in the mold used for making the keys when they are made by molding. Alternatively, the marking may be an operation that is performed directly on the keys after they have been made.

In advantageous exemplary embodiments, the connection face of the housings of the first and second connectors, respectively, are adapted to enable each key to be installed and removed manually. The term “installed and removed manually” as used in the present invention means that it is possible to install and remove a key by hand alone without help from any tool. Preferably the manual installation and removal of each key is performed from the connection faces of the housings. An operator can thus quickly and easily fasten the keys in the housings with a determined coding combination, and can also remove them quickly and easily.

In advantageous exemplary embodiments, a key includes a fastener collar in its central portion between its two end portions, the collar co-operating by snap-fastening with at least one elastically deformable fastener tab arranged in the housing of the first or second connector in order to fasten the key in the housing. The fastener tab(s) may be molded directly and integrally with the housing of a connector. This provides a fastener system that is simple and inexpensive for the polarizing keys. The fastener tab(s) may be generally in the form of clips.

Each housing may also include a shoulder against the rear of the fastener collar comes into abutment, while the front of the collar is snap-fastened with the tab(s). This provides a kind of double positioning and holding system for positioning and holding a key in the housing: in front by means of the fastener tab(s); and at the rear by coming into abutment against the shoulder.

Advantageously, the collar includes on its outer periphery a plurality of second visual indicators, defining a plurality of angular positions of the key relative to the axis (X), and a lateral end of a housing includes a viewing window for viewing one of the second visual indicators when the corresponding key is fastened in the housing.

In an advantageous variant, the collar is of polygonal external section transversely to the axis (X1, X2) of the key, and the lateral end of the housing defines around the tab(s) a recess of polygonal internal section complementary to the section of the collar, the housing and the collar co-operating by mutual engagement of the complementary polygonal sections in order to define one of the plurality of given angular positions for the key relative to the axis X of the housing. In other words, in this variant, the polarizing keys are advantageously prevented from turning about their axes in the given angular position because the faces of the polygonal section of the collar are blocked by the complementary faces of the recess.

According to an advantageous characteristic, the external section of the collar is octagonal.

The visualization window may be provided laterally in the recess. This is advantageous, in particular in a factory for fabricating and assembling harnesses or connectors, whenever an operator is testing the connection of a connection assembly that is polarized by means of keys in accordance with the invention. The operator can then easily see on the sides of the connectors whether the polarizing code of the second visual indicators is indeed the appropriate code.

The plurality of second visual indicators is preferably a succession of digits, such as 1 to 8. It may be achieved by marking the keys. The marking is preferably the result of a shape formed in the mold for the keys when the keys are made by molding. Alternatively, the marking may be an operation that is performed directly on the keys after they have been made.

In first exemplary embodiments, at least the collars of the two keys have the same transverse dimensions, and the housings of the first and second connectors are adapted to receive equally well a portion of a key that is of male type or of female type. In other words, in these first exemplary embodiments, either one of the two keys can be installed and/or removed equally well in association with the plug or the socket of the connection assembly. This also makes it possible to double the number of coding combinations between the housings of the two connectors. Thus, if one key has two end portions of the male type and the other key has two end portions of the female type, it is possible to receive a male key equally well either in the housing of the plug or in the housing of the socket, and likewise it is possible to receive the corresponding female key equally well in the housing of the plug or in the housing of the socket.

In second exemplary embodiments, as an alternative to the first exemplary embodiments, at least the collars of the two keys are of transverse dimensions that are different, and the lateral end of the housing of the first connector is adapted to receive only the female type portion of the key having the larger collar when snap-fastened by the tab(s), while the housing of the second connector is adapted to prevent said key having the larger collar from being snap-fastened by the tab(s).

In these second exemplary embodiments, the assembly may include a solid cylinder projecting from the lateral end of the housing of the first connector in order to prevent a male type key portion from being received therein. The second exemplary embodiments make it possible to eliminate the possibility of a key being mounted equally well in a plug housing or in a socket housing. Thus, when only a female key can be mounted in a housing of the first connector, such as a plug, its larger-size collar prevents it from being snap-fastened to the housing of the second connector. And the male key cannot then be received in the first connector, preferably because of the presence of the solid cylinder with which it interferes mechanically in the event of an attempt at inserting it therein. In other words, the second exemplary embodiments serve to prevent an operator from making a potential error of interchanging the keys between the housings of the first and second connectors, respectively.

According to an advantageous characteristic, the first and second visual indicators together define a polarizing code having a plurality of combinations (A1 to A8, B1 to B8). The number of coding combinations may be equal to 32.

The two end portions of one key are preferably of the male type while the two end portions of the other key of the pair are preferably of the female type. Thus, for a pair of two keys of the invention, it is advantageous to define one key as being of male type only and the other key as being of female type only.

In advantageous variant exemplary embodiments, a key portion of female type is constituted by a cylinder having a rectilinear slot formed therein along the cylinder, whereas a key portion of male type is constituted by a cylinder having at least one rectilinear spline formed thereon along the cylinder, complementary to the slot.

Preferably, three rectilinear slots are arranged inside the cylinder, the slots being spaced apart from one another in angular positions, and three splines are arranged on the cylinder, being spaced apart from one another in the same angular positions as the slots. It is preferable to define three slots and three corresponding splines since that makes it possible firstly to have better mechanical guidance while coupling together the two polarizing keys, and secondly to have better mechanical strength for the keys in the event of a coupling error.

The connection assembly of the invention may be adapted to be mounted on a panel.

The first and second connectors are advantageously adapted to be locked together. Thus, the first connector may include a cap slidably mounted on the housing between a locking position in which it co-operates with at least one locking peg of the second connector, and an unlocking position in which it projects beyond a lateral end of the housing opposite from its lateral end from which the corresponding polarizing key projects.

The invention also provides a set of polarizing keys for use in a connection assembly as defined above, the set comprising at least one pair of two polarizing keys each key being of elongate shape along an axis (X1, X2) and including at each of its ends a portion having a peripheral surface that is provided with at least one projecting and/or hollow shape, and by the fact that each end portion of one of the two keys in a given pair is adapted to engage by complementary shapes with a single end portion of the other one of the two keys of the same pair along their coinciding axes (X1=X2) and in only one relative angular position between them.

MORE DETAILED DESCRIPTION

Throughout the present application, the terms “front”, “rear”, “top”, and “bottom” should be considered with reference to a connection assembly of the invention having two mutually-connected connectors2,3. Thus, the front face of the connector3, which can also be referred to as its “connection” face, is the face beside which the connection is made with the complementary connector2.

FIGS. 1,2,7, and8show a connection assembly given overall reference1in a first embodiment of the invention. This connection assembly1comprises a first multi-contact connector given overall reference2and a second multi-contact connector given overall reference3. The multi-contact connectors2and3are of complementary type, it being possible, by way of example, for the first connector2to be of the male type and in particular to be a plug, while the second connector3is of the female type, being in particular a socket.

However, in all of the figures described, the first connector2is a female plug and the second connector3is a male socket.

Each multi-contact connector2,3conveys optical signals, electrical signals, or power. In a variant, signals or power of different types may be conveyed by each of the multi-contact connectors, in which case contacts of different sizes and different types are arranged simultaneously in the connectors.

The contacts may be single or multiple contacts such as coaxial or tri-axial contacts, quadrax contacts, RJ45 contacts, or any type of high data rate contact. The contacts may equally well be “expanded beam” type optical contacts with lenses, or “physical contact” contacts of the ARINC 801 or EN 4531 type, or indeed optoelectronic contacts.

The first multi-contact connector2mainly comprises a housing4that is made as a single piece of plastics material, in the example described.

The housing4includes a plurality of cells42arranged in the housing4extending from a rear face40to a front face41, which face may also be referred to as a “connection” face, so as to face the second connector3when the connectors2and3are locked together.

In the example described, the faces40and41are parallel and extend perpendicularly to the rectilinear axis X of the cells42, this rectilinear axis X being referred to below as the “connector axis”.

The housing4may include two arms43extending beyond the connection face41on either side thereof, these arms43possibly including guide slots44as described in detail below. When the housing is rectangular in shape in section perpendicularly to the axis X, the arms43may extend parallel only to the small sides of the housing4. The housing4may be made as a single portion or as two portions in order to make it easier to install holder parts as described below.

Although not shown, the first connector2may have an attachment portion extending the housing4along the axis X from its rear face40. By way of example, this attachment portion has two branches, each having one end releasably hooked on the housing4and another end connected to a junction portion. The junction portion may define a plurality of attachment zones. Although not shown, each attachment zone may present a semicircular reception surface against which the cables to which the first connector2is connected can bear and/or be fastened.

The first connector2may include a front gasket (not shown) for placing on the connection face41of the housing4, and the front gasket may include holes that come into register with the cells42when the gasket is in place on the connection face41. By way of example, the front gasket may be made of silicone.

The first connector2may include a rear gasket4′ for placing against the rear face40of the housing4. Like the front gasket, this rear gasket4′ may have as many holes as the housing4has cells42, the holes in the rear gasket coming into register with the cells42when the rear gasket4′ is in place on the rear face40of the housing.

The cells42receive portions of the contacts45of the first connector2. As shown better inFIGS. 11A to 11C, when the contacts45are in place in the housing4, they also project out from the cells42, i.e. in the holes in the front gasket30, if any, so as to be cantilevered out. Each contact45thus includes a portion that is received in a cell42and a portion that projects beyond the connection face41of the housing4. The portion that is received in a cell42may be of a length that lies in the range 50% to 75% of the length of the contacts45.

A holder part (not shown) may be placed in each cell42close to the rear face40, this holder part serving to fasten a contact45in the housing4. In a variant, the holder part may be molded and incorporated in the housing4, in particular when the housing4is made as two portions.

According to the invention, the first connector2includes a projection46at one of its lateral ends, the projection forming a housing with a cylindrical inside shape over a major fraction h2 of its length as constituted by its end wall. Two elastically deformable fastener tabs47are arranged around the recess46at the top end48of the projection, e.g. by being diametrically opposite to each other. The top end48of the projection46has an internal cross-section that is polygonal, and that is octagonal in the example described. A shoulder49is provided between the end wall of the recess and the top end48of the projection.

The functions of the recess46of the projection, of the fastener tabs47, and of the shoulder49are described in detail below.

Similarly to the above-described first connector2, the second connector3of the connection assembly1may comprise a housing5made as a single piece, a cable attachment portion (not shown), and a rear gasket5′.

The housing5has a plurality of cells52running from a rear face50to a front face51, which may also be referred to as a “connection” face, that faces the first connector2when the connectors2and3are locked together.

In the example described, the faces50and51are parallel and they extend perpendicularly to the rectilinear axis X of the cells52, this rectilinear axis X also being referred to below as the “connector axis”.

The cells52receive contacts (not shown) of complementary type to the contacts45, for the facing cells42.

As shown better inFIGS. 1 and 2, one or more locking pegs53may be provided at least on the top face of the housing5. Other locking pegs may also be provided on the bottom face of the housing5. In the examples under consideration, the locking pegs53are made integrally with the housing5.

Unlike the first connector2, the second connector3may include fastener means for fastening to a panel, which means are not shown.

Also unlike the first connector2, and as can be seen better inFIGS. 11A to 11C, the second multi-contact connector3also includes, at one of its two lateral ends, a projection54from which there projects a guide peg55serving to guide the connector3in an opening in a panel.

In the invention, and in similar manner to the first connector2, the second multi-contact connector3also includes, at its other lateral end, a projection56forming a recess of cylindrical inside shape over the major fraction h3 of its length that constitutes its end wall. Two elastically deformable fastener tabs57are arranged around the recess56at the top end58of the projection, e.g. by being diametrically opposite each other. The top end58of the projection56has an internal cross-section that is polygonal, specifically octagonal in the example described. A shoulder59is provided between the end wall of the recess and the top end58of the projection.

The functions of the recess56in the projection, of the fastener tab57, and of the shoulder59are described in detail below.

Finally, the second connector3includes guide splines34on either side of the front face51of the housing in order to co-operate with guide slots44of the first connector2so as to provide the connectors with guidance in translation along the axis X while they are being connected together. This is described in detail below with reference toFIGS. 11A to 11C.

The two multi-contact connectors2,3of the connection assembly are advantageously configured to be locked together. More precisely, a locking cap6is mounted to slide transversely relative to the housing4of the first connector2between a locking position and an unlocking position, and back again.

As shown better inFIGS. 1 and 2, the locking cap6may present a U-shaped section in a plane perpendicular to the axis X of the connector2. The cap6then presents an end wall60that faces a side face43of the housing4and two parallel branches61that respectively face a portion of the top face of the housing4and a portion of the bottom face of the housing4.

As shown inFIGS. 1 and 2, one or more windows62may be formed in one of the branches61or in both of the branches61. These windows62, when observed from above or below the housing4, may be substantially L-shaped. The long dimension measured between two opposite edges of a window62defines the amplitude of the sliding movement of the locking cap6relative to the housing4on passing from a locking position to an unlocking position.

As shown inFIGS. 1 and 2, in order to lock the first connector2and the second connector3together, the procedure is as follows.

During a first step, the first connector2with the locking cap6in the unlocking position is pushed, e.g. by hand, towards the second connector3that has previously been inserted through an opening in a panel and secured to said panel. At the end of this step, the locking cap6is in contact with the housings4and5. Still at the end of this step, the locking pegs53of the housing5are received in the short portion of the L formed by each window62of the locking cap6.

During a subsequent step, force is exerted, e.g. by hand, perpendicularly to the axis X. This force causes the locking cap6to slide relative to the housings4and5, transversely to the axis X.

The sliding of the cap6causes each peg53to advance along the long portion of the L of each window62. At the end of this step, each peg53is in abutment against an edge of the window62and is blocked thereagainst. The cap6is then in the locked position, securing the connectors2and3to each other.

As can be seen inFIGS. 11A to 11C, the maximum extent occupied by the connection assembly1in the example described is determined by the distance L between the two projection means54and56of the housing5of the second connector3.

In an embodiment of the connection assembly1of the invention, the length measured along the axis X between the rear face40of the housing4and the free end of each arm43is 25 millimeters (mm). Still in this example, the height of the housing4measured between its top face and its bottom face is 14 mm, the width of the cap6is 62 mm, and the amplitude through which the cap6moves on passing from its unlocked position to its locked position, and back again, is 8 mm.

Concerning the second connector3, the distance L between the two projections54and56as measured perpendicularly to the axis X is 80 mm, the height of the housing5is 14 mm, and the length of the housing5as measured along the axis X between the two opposite faces is 23.50 mm.

The values given above for the distances are naturally given purely by way of indication, and the values in other examples could be greater than or less than those given above.

The connection assembly1of the invention also includes a polarizing system constituted by a pair of polarizing keys7,8, each key being of elongate shape along an axis (X1, X2).

According to the invention, each key7,8projects from only one of the lateral ends46,56of a housing4,5beyond its connection face41,51.

Also according to the invention, each key7,8includes, at each of its ends, a respective portion70,71;80,81with a peripheral surface that is provided with at least one projecting shape83,84and/or recessed shape73,74.

Still according to the invention, each end portion70,71of one of the two keys7is adapted to engage by complementary shapes with a single end portion, respectively80,81of the other one of the two keys8along their common axis (X1=X2), and when they are in a single relative angular position.

Finally according to the invention, each polarizing key7,8is adapted to be fastened via one70,80or the other71,81of its end portions to the housing4of the first connector2and/or to the housing5of the second connector3in a plurality of given angular positions relative to the axis (X).

In all of the figures described, the key7is a female key, i.e. it has two female type end portions70and71, and the key8is of male type with two end portions80and81of male type.

As shown inFIGS. 3A and 3B, the female key7has an end portion70on which there is marked a visual indicator A and a second end portion71on which there is marked a visual indicator B.

The two end portions70and71are separated by a fastener collar72of octagonal section. A succession of digits 1 to 8 is marked on the collar72. More precisely, one digit is marked on each face of the octagonal section so as to form a succession. This succession can be seen in increasing order on turning the key7about its axis in a counterclockwise direction.

The end portion70is a cylinder having three rectilinear slots74formed therein along the cylinder, which slots are spaced apart from one another in angular positions.

The end portion71is a cylinder having three rectilinear slots73formed therein along the cylinder and spaced apart from one another with angular positions. The spacing between the slots73of the end portion71is different from the spacing between the slots74of the end portion70.

In the example shown, two adjacent slots74are spaced apart from each other by an angle of 90°, while the third slot74is spaced apart from each of the other two slots74by an angle of 135°.

In the example shown, two adjacent slots73are spaced apart from each other by an angle of 180°, while the third slot73is spaced apart from each of the other two slots73by an angle of 90°.

As shown inFIGS. 3A and 3B, the male key8has an end portion80on which there is marked a visual indicator A, and a second end portion81on which there is a visual indicator B.

The two end portions80and81are separated by a fastener collar82of octagonal section. A succession of digits from 1 to 8 is marked on the collar82. More precisely, one digit is marked on each face of the octagonal section so as to form the succession. This succession is visible in increasing order when the key8is turned about its axis in the clockwise direction.

The end portion80is a cylinder having three rectilinear splines84formed along the cylinder, the splines being spaced apart from one another in angular positions.

The end portion81is a cylinder having three rectilinear splines83formed along the cylinder, which splines are spaced apart from one another in angular positions. The spacing between the splines83of the end portion81is different from the spacing between the splines84of the end portion80.

The three rectilinear splines83are of shape complementary to the three slots73being spaced apart from one another in the same angular positions. Thus, in the example shown, two adjacent splines83are spaced apart from each other at an angle of 180°, while the third spline83is spaced apart from each of the other two splines83at an angle of 90°.

The three rectilinear splines84are of shape complementary to the three slots74, being spaced apart from one another at the same angular positions. Thus, in the example shown, two adjacent splines84are spaced apart from each other by an angle of 90°, while the third spline84is spaced apart from each of the other two splines84by an angle of 135°.

In other words, mutual engagement by complementary shapes is possible between the splines73and the slots83in only one position, defining a code B, and between the splines74and the slots84in only one position, defining a code A.

As explained below, depending on the angular positions of the keys7,8relative to the axis X of the housings4,5of the connectors2,3, it is possible to define given coding associating the letter A or B with a given digit 1 to 8 giving a maximum number of 32 combinations.

In an embodiment of the connection assembly1of the invention, each key7or8has a length l of 15 mm and a diameter Ø for a collar72,82, i.e. a distance between two facing flats of the hexagon, that is of the order of 5.5 mm. The recesses46,56are of a length h of about 10 mm.

The values given above for the distances are naturally given purely by way of indication, and the values in other embodiments could be less than or greater than the values given above.

There follows a description of how the polarizing keys7,8are mounted manually in the housings4,5of the two connectors2,3.

One of the keys7or8is taken manually and is positioned firstly to define which end portion70or71, or81is to be received in the recess46or56as formed in one of the projections of the housings4or5. This orientation thus serves to show that one of the first visual indicators, A or B, that it is desired to have visible once assembly has been completed.

The key7or8is also positioned depending on the desired angular position relative to the axis X. In other words, in the example described, the faces of the octagonal section are positioned depending on the digit 1 to 8 that it is desired to see from the side of the housing4or5.

Thereafter, the key7or8is inserted in the recess46or56until its fastener collar72,82comes firstly into abutment against the shoulder49,59made in the recess, and secondly snap-fastens with the two fastener tabs47or57.

Once this snap-fastening step has been performed, the key7or8is fastened to the housing4or5of the selected connector2or3, and the angular positioning determined relative to the axis X is implemented.

The same steps are performed for the other key8or7with the other housing5or4of the other connector3or2while taking care to comply with the corresponding positioning of the end portion71or70,81or80in the recess56or46and the corresponding angular positioning about the axis X.

In order to remove each of the two keys7,8manually, it suffices to exert a manual traction force thereon from the rear towards the front of the connector2,3in which it is received. A simple traction force suffices to release the snap-fastening of the fastener tabs47,57on the collar72,82of the key7,8.

An example combination A5 is shown inFIG. 5. In this figure, it can be seen that the male key8is snap-fastened inside the recess56of the second connector3firstly so as to cause the digit 5 to appear laterally so that it can be seen through the viewing window90provided for this purpose in the projection56, and secondly so as to cause the letter A to be visible at its end, which can be viewed when looking at the connection face of said second connector. In similar manner,FIG. 5shows that the female key7is snap-fastened inside the recess46of the first connector2so as to cause the digit 5 to appear laterally so that it can be viewed through the viewing window91provided for this purpose in the projection46, and so that the letter A can be seen laterally by viewing from the side of said first connector2. Thus, an operator in a factory assembling the polarizing keys7,8in their respective connectors2,3can easily see and thus check the correct code depending on the determined combination, and specifically the code A5 as inFIG. 5.

FIGS. 1 to 7show a first embodiment of the invention in which the female key7or the male key8can be mounted equally well on the first connector2or the second connector3. This embodiment is advantageous and makes it possible to double the number of coding combinations between the housings4,5up to 32 combinations in the embodiment shown.

In this first embodiment, the collars72,82of the two keys7,8have the same transverse dimensions, and each recess46,56of the housing4,5can receive equally well an end portion70,71of the female key7or an end portion80,81of the male key8with snap-fastening being possible in any of those configurations because of the same sizes and the same arrangement of the shoulders49,59and of the fastening tabs47,57. Nevertheless, this first embodiment can suffer from a drawback in that it can lead to wrong assembly if an operator were inadvertently to install a male key8instead of and in the place of a female key7, and vice versa.

FIGS. 8 to 10show a second embodiment that makes it possible to eliminate that drawback of the first embodiment. In other words, in this second embodiment, the female key7can be mounted only in one of the connectors, the first connector2in the embodiment shown. Likewise, the male key8can be mounted in only one of the connectors, the second connector in the embodiment described.

In this second embodiment, the transverse dimensions of the collar72of the female key7are made larger than those of the collar82of the male key8, thereby preventing the female key7from being mounted in the recess56of the housing5that is adapted solely to receive the male key8. In this second embodiment, the transverse dimensions of the end portions70,71of the female key may also be enlarged. The resulting mechanical interference between the female key7and the recess56is shown inFIG. 9: in this figure, it can clearly be seen that the female key7comes into abutment against the periphery of the recess56without it being possible for it to be received therein.

Also in this second embodiment, the end wall of the recess46in the housing4is adapted solely to receiving the female key7and is fitted with a solid cylinder9. When the female key7is inserted into the recess46, the solid cylinder9penetrates into the inside of one of the end portions70,71without that leading to any problem of assembly. If an attempt is made to insert the male key8in the recess46, the solid cylinder9comes into abutment against the male key8and thus prevents it from being snap-fastened. The mechanical interference between the solid cylinder9and the male key8is shown inFIG. 10. In this figure, it can clearly be seen that the male key8comes into abutment against the solid cylinder9.

Naturally, althoughFIGS. 8 to 10show a configuration in which it is impossible to insert the female key7in the second connector3(socket) or the male key8in the first connector2(plug), it is naturally possible to provide the inverse configuration.

The connection steps, i.e. the steps of mechanically and electrically connecting the connectors2and3with their contacts together and mechanically coupling them via the polarizing keys7,8are shown inFIGS. 11A to 11C.

Firstly, the housings4,5of the connectors2,3are put into alignment on their axis X so that their connection faces41,51are facing each other. In establishing this alignment, the guide slots44in the arms43of the housing4of the first connector2are put into contact with the guide splines34of the housing5of the second connector3, as shown inFIG. 11A.

Then the housings4,5are slid towards each other with the help of the guide slots44and splines34until the two polarizing keys7,8are put into contact, as shown inFIG. 11B.

If the two facing end portions70,80or71,81of the two polarizing keys7,8can be mutually engaged, then the housings4,5can continue to be slid towards each other, thereby making it possible to continue establishing the connection between the housings4,5and mechanical coupling between the polarizing keys7,8, as shown inFIG. 11C.

Once connection has been completed, the connection faces41,51are in contact flat against each other.

The invention is not limited to the above-described embodiments.

The term “comprising a” should be understood as meaning “comprising at least one”, unless specified to the contrary.