Power connector for a printed circuit

A power connector for a printed circuit, the connector comprising:

CROSS-REFERENCE TO RELATED PATENT APPLICATIONS

This application is a National Stage of Application PCT/FR02/00989, filed Mar. 21, 2002, incorporated herein by reference in its entirety.

BACKGROUND

The present invention relates to a power connector usable, in particular, with a printed circuit card, e.g. for use in controlling electrical actuators, and, in particular, electromagnetic actuators.

In the automotive field, an ever-increasing number of high-power electrical actuators are being used. At present, power is supplied to such actuators by power modules associated with a card having power conductor tracks leading to the actuators. A problem associated with that type of power supply is connecting said power tracks to the power supply conductors of the actuators, where such connection must be releasable so as to enable the power supply card to be replaced in the event of failure. In addition, very tight constraints on size lead to a requirement for the power supply conductors to depart from the printed circuit parallel therewith, and close thereto.

Numerous connector structures are presently in existence. Nevertheless, none of them constitutes a good match for satisfying the above-mentioned constraints.

SUMMARY

One embodiment provides a power connector for a printed circuit. The connector comprises an insulating socket provided with a bearing face bearing on the printed circuit, and with a housing associated with an opening disposed laterally, at least one pin passing through the bearing face perpendicularly thereto and having a connection portion which extends projecting into the housing and presents two faces parallel to a plane perpendicular to the opening, an insulating support arranged to be inserted at least in part in the housing through the opening, and at least one plug secured to the insulating support and provided with two flexible tabs for pressing against the faces of the connection portion of the pin.

The structure of the connector is thus relatively compact while allowing relatively high-power electric current to be conveyed, and with the support being easy to insert into the socket parallel to the bearing surface. This connection therefore does not require conductors to be curved in order to cause them to depart parallel to the printed circuit. This contributes to minimizing the volume occupied for connection purposes.

Preferably, the pin comprises a tab which is cut out from a conductive plate forming the printed circuit, and it is folded so as to extend perpendicularly to the plate.

The pin is then made in a manner that is particularly simple, integrally with the conductive plate forming the printed circuit.

MORE DETAILED DESCRIPTION

The invention is described herein with reference to a printed circuit card for receiving a power module610(FIG. 7) of conventional type and associated with a power connector for supplying power to an electrical actuator612(FIG. 7) which is connected to the power module612via the connector.

With Reference toFIGS. 1 to 5a, the card1comprises an insulating plate2having two opposite faces3and4carrying a control circuit5and two power circuits6and7.

The control circuit5is implemented in the form of conductor tracks printed on the face3of the insulating plate2. The control circuit5is connected to the power module to transmit low power control signals coming from and going to the power module, and for connecting the power circuits6and7to the power module via short segments capable of conveying higher-power signals without being subjected to heating which might damage them.

The power circuits6and7are of the lead frame type comprising, respectively, a conductive plate8fixed to the face4of the insulating plate2, and a conductive plate9fixed to the conductive plate8. The conductive plates8and9are made of copper having thicknesses sufficient to conduct power, and which include conductor tracks. The conductive plates8and9also include holes40,41for passing connection pins of the power module and any other components that might be mounted on the card (e.g. coils12, ofFIG. 2). The holes40,41have an opening size greater than the size of the connection pins so that the connection pins do not come into contact with the plates8and9.

Each of the conductive plates8,9is cased in an insulating layer10,11(FIG. 2). The insulating layers10and11are formed in this case by flexible sheets of insulating material having an adhesive face enabling the sheets to be held on the conducive plates8and9. By means of the insulating layers10and11interposed between the conductive plates8and9, the power circuits6and7can be placed one on the other, thereby limiting the volume they occupy. The insulating layers10and11have openings in register with the holes40and41.

Tracks of the conductive plate8have end portions38extending substantially perpendicularly to the conductive plate8projecting from the insulating layer10. In the same manner, tracks of the conductive plate9comprising end portions39extend substantially perpendicularly to the conductive plate9projecting from the insulating layer11. It will be observed that the power circuits can thus form subassemblies ready for mounting on the printed circuits.

The end portions38are received in holes42formed in the insulating plate2. Each of the end portions38has a free end fixed to and projecting from the control circuit5. In analogous manner, the end portions39are received in holes43formed in the power circuit6and in the corresponding holes42in the insulating plate2, and each has a free end fixed to and projecting from the control circuit5. The free ends of the end portions38and39are fixed to the control circuit5by soldering.

As mentioned above, the segments of the control circuit5to which the end portions38and39are fixed are very short in length so as to make it possible for them to conduct relatively high currents (about 20 amps) without being subjected to excessive heating which might damage them.

The end portions38and39serve firstly to connect the conductive plates8and9to the control circuit5in order to convey power signals between the power module and the actuator, and secondly to fasten the power circuits6and7mechanically to the insulating plate2.

In order to improve this fastening, additional end portions38′,39′ are provided which are soldered to segments of the control circuit that are not connected to the power module and that serve only for fastening the power circuit in question.

It will be observed, in particular inFIG. 5b, that the flexibility of the insulating layers10and11enables them to match the shape of the bent region of an end portion38, said bent region projecting from the plate8into an opening of the conductive plate9. This makes it possible to further limit the overall size of the superposed power circuits.

The power circuits6and7of the card1are connected to the electrical actuator with which they are to co-operate via a connector13.

The connector13comprises a socket14which is made of insulating material and which comprises both a bearing face15bearing on the power circuit7, and a housing16. The housing is associated with opening17that opens laterally.

Pins18and19pass through the bearing face15perpendicularly thereto and extend into holes20in the socket14.

The pins18extend in openings of the power circuit7and each has one end21connected to the conductive plate8and an opposite end forming a connection portion22which projects into the housing16. The end21is extended away from the connection portion22by one of the additional end portions38′ that are soldered to segments of the control circuit5that are not connected to the power module. The connection portion22has two faces23parallel to a plane perpendicular to the opening17(the plane of the sheet inFIG. 2) and a chamfered edge24facing towards the opening17. The pins18possess anchoring barbs25engaged in the insulating socket14.

The pins19are disposed beyond the pins18, each having one end26connected to the conductive plate9and an opposite end forming a connection portion27which projects into the housing16. The end26is extended away from the connection portion27by one of the additional end portions39′ received in the holes42and soldered to segments of the control circuit5that are not connected to the power module. The connection portion27has two faces28parallel to a plane perpendicular to the opening17(the plane of the sheet inFIG. 2) and a chamfered edge29facing towards the opening17. The pins19possess anchoring barbs30engaged in the insulating socket14.

In this case, the pins18and19are formed by tabs cut out in the corresponding conductive plate8or9and folded to extend perpendicularly thereto through the corresponding insulating layer10or11.

The pins18and19are disposed in two rows that are offset from each other. The pins19are adjacent to the opening17and are of a height in the housing16which is less than the height of the pins18. This arrangement makes it possible to limit the volume occupied by the connector13.

The socket14also serves as a support on which the coils12are mounted with their connection pins extending in holes formed in register therewith in the socket14, in the power circuits6and7, and in the insulating plate2; the connection pins of the coils12having free ends projecting beyond the control circuit5and soldered thereto.

The connector also comprises a support31which is made of an insulating material and is arranged to be inserted at least in part in the housing16via the opening17.

The support31has housings32each presenting a respective longitudinal slot33for receiving a pin18or19, and each receiving a plug34(FIG. 4) fixed in a housing32. Each plug34possesses one end connected to a conductor44(FIGS. 1 and 4) for connection to the electrical actuator (only two conductors are shown inFIG. 1) and an opposite end carrying two flexible tabs35facing the slot33, which tabs35are elastically deformable between a first state in which the two flexible tabs35present respective surfaces36pressed against each other, and a second state in which the surfaces36are spaced apart from each other (seeFIG. 4in particular). The flexible tabs35have diverging free ends37.

The plugs34that connect to the pins18project beyond and are located above the plugs34that connect to the pins19(seeFIG. 1).

To make the card, the socket14is engaged by force onto the pins18and19. The barbs25and30then become anchored in the walls of the holes20and hold the socket14pressed against the power circuit7via the bearing face15. The control circuit5is made on the face3of the support plate2while the power circuits6and7and then the power module and the coils12are mounted on the insulating plate2via its face4. The free ends of the end portions38,39,38′,39′ and the connection pins of the power module and of the coils12are then soldered to the control circuit5. Soldering is preferably performed in this case by a flow soldering technique. It should be observed that all of the components of the card, including its power circuits6and7are fastened to the insulating plate2in this way and are connected to the control circuit5in a manner that is particularly easy and may be done in a single operation.

Connection is established by engaging the support31in the housing16through the opening17in a direction parallel to the bearing face5and to the insulating plate2. Such insertion does not require the conductors44to be curved in order for the conductors44to extend from the card1in a direction that is parallel to the card1, thus making it possible to provide a connection of minimum size.

When the connection portions22and27of the pins18and19are engaged in the slots33, the free ends37of the plugs34come into contact with the chamfered edges24and29of the pins18and19. The free ends37are spaced apart by said chamfered edges24so as to bring the surfaces36of the plugs34into contact with the faces23and28of the pins18and19. The elasticity of the material constituting each plug34serves to keep the surfaces36thereof in contact with the faces23or28of the corresponding pin18or19. The depth of the slot33determines the depth to which the pin18,19can be inserted into the plug34in such a manner that, at maximum insertion, the surfaces36and the faces23and28are in register.

It will be observed that the structure of the connector13is thus relatively compact, which provides good transmission of electric current of relatively high power and also makes it easy to insert the support31into the socket14parallel to the bearing surface15.

In a variant, as shown inFIG. 6, the insulating layers10and11are made of a rigid insulating material molded around the plates8and9, and the socket14is made out of the same material so as to constitute, together with the insulating layers10and11, a single piece45. The conductive plates8and9are then used as inserts in the mold into which the material for constituting the part45is injected.

Naturally, the invention is not limited to the embodiment described and variants can be applied thereto without going beyond the scope of the invention as defined by the claims.

In particular, although the pins18and19are described as being cut out in the conductive plates8and9, and as being folded so as to extend perpendicular to the plates, thereby simplifying the structure of the power circuits6and7, the pins18and19could be separate pieces fitted to the power circuits6and7.

In addition, the support plate2may be made of a material that conducts heat, such as aluminum (with an insulating layer then being interposed between the plate and the circuit), thereby contributing to cooling the circuits.

The insulating layers10,11need cover only one face of each conductive plate8,9.

Furthermore, the card could have only one power circuit or could have more than two power circuits.

The pins18and19could be arranged differently, for example their positions could be interchanged.