EP2766978A2

EP2766978A2 - Device for a motor vehicle alternator regulator

Info

Publication number: EP2766978A2
Application number: EP12780225.4A
Authority: EP
Inventors: Pierre Tisserand; Christophe Porte
Original assignee: Valeo Equipements Electriques Moteur SAS
Current assignee: Valeo Equipements Electriques Moteur SAS
Priority date: 2011-10-12
Filing date: 2012-10-08
Publication date: 2014-08-20
Also published as: FR2981522B1; WO2013054023A2; WO2013054023A3; FR2981522A1

Abstract

The present invention relates to a device (100) for a motor vehicle alternator regulator comprising a plastic brush-holding support plate (10). According to the invention, the device comprises a circuit board (20) that forms the electric circuit of said regulator, this circuit board (20) being secured to the brush-holder support plate (10) and comprising an opening (23) to accept an integrated circuit (60) connected to the circuit board (20) by electrical connections. Typically, this circuit board is a printed circuit board or "PCB".

Description

Device for regulating an alternator of

motor vehicle

Technical field of the invention

The present invention relates to a device for regulating a motor vehicle alternator.

The present invention also relates to a motor vehicle alternator comprising such a device for a regulator.

Conventionally, a motor vehicle alternator comprises a regulator adapted to regulate the voltage and consequently the current produced by the alternator. The regulator is arranged on a fixed part of the alternator and is formed by a brush holder box made of insulating plastic material incorporating an electrical circuit forming the control electronics.

The electrical circuit is formed by conductive traces which are embedded in the brush holder housing. The traces are formed by die cutting (stamping) of a metal plate in a specific tool. In addition to the metal traces, the electric circuit of the regulator can also comprise discrete electronic components welded directly on the traces or on pieces of traces folded vertically in the form of a fork.

The metal traces are then overmoulded with insulating plastic material so as to produce a sealed brush-holder housing.

The use of additional components welded to the metal traces is relatively limited and requires a specific intervention on the metal traces. In addition, overmoulding, performed on the metal traces, stresses the components, such as the anti-interference capacitor, in temperature (over-molding temperature greater than 300 ° C.) and in pressure (over-molding pressure greater than 300 bars). This increases the risk of component damage.

In addition, the method of producing such a brush-holder housing is relatively complex and time-consuming because it requires in particular: a stamping operation for the production of traces;

an operation of premoulding the traces to maintain the traces in position on a broom support plate;

an operation of electrically separating the traces from each other so as to produce the desired electric circuit;

- a welding operation of the discrete components on the metal traces;

- A premolding operation and overmoulding of the assembly so as to achieve a sealed brush holder housing;

an electrical test operation verifying the integrity of the components and the isolation of the traces.

Thus, the brush-holder regulators are complex pieces to realize requiring multidisciplinary know-how, especially in the field of plastics, in the field of surface treatment, and in the field of electronics.

In addition, manufacturers want to integrate more and more electronic components in the tracks which therefore increases the risk of breakdowns and increases the costs of achieving such a regulator.

In this context, the present invention aims to solve the aforementioned drawbacks.

To this end, the invention proposes a device for regulating a motor vehicle alternator comprising a plastic brush support plate. According to the invention, the device comprises a circuit board forming the electric circuit of the regulator, the circuit board being secured to the brush holder support plate and having an opening for receiving an integrated circuit connected to the circuit board by links. electric.

Typically, this circuit board is a printed circuit board or PCB (for "Printed Circuit Board" in English). The PCB is formed by a support, generally a plate, for electrically connecting a set of electronic components together, for the purpose of producing a complex electronic circuit. The PCB consists of an assembly of one or more thin layers of copper separated by an insulating material. The copper layers are etched by a chemical process to obtain a set of tracks. The tracks are often covered with a layer of colored varnish to protect the tracks from oxidation and possible short circuits.

The PCB is a true standard, perfectly mastered, of the electronics industry and allows a simple, economical and tailor-made implementation of the device according to the invention so as to meet the requirements of different manufacturers of alternator.

In addition, the use of the PCB allows for complex assemblies comprising a plurality of discrete components while avoiding the risk of damage to the components by performing overmolding.

In addition to the main features which have just been mentioned in the preceding paragraph, the regulator device of a motor vehicle alternator according to the invention may have one or more additional characteristics below, considered individually or in any combination technically. possible:

- The device comprises protective means adapted to cover said circuit board and positioned in abutment on said brush holder support plate;

said protection means are arranged so as to provide a space between said circuit board and said protection means;

said space is filled by sealing means;

the sealing means are formed by a gel or a resin;

the device comprises sealing means positioned between said protection means and said circuit board;

said circuit board is formed by conductive tracks adapted to receive discrete components;

said circuit board comprises brush-holder conductive tracks adapted to connect said card to connectors of said brush-holder support plate;

said brush holder conductive tracks are electrically connected by welds, for example, aluminum wire welds; said brush holder conductive tracks are overmolded;

said circuit board provides electrical connections with the electrical machine forming the alternator (terminal B +, ground and phases), these links being integrated in the brush holder with an overmoulding or without overmolding;

The invention also relates to a regulator for a motor vehicle alternator characterized in that it comprises:

a regulator device according to the invention;

an integrated circuit; and

- a radiator.

The invention also relates to an alternator of a motor vehicle characterized in that it comprises a regulator according to the invention.

Other characteristics and advantages of the invention will emerge clearly from the description which is given below, by way of indication and in no way limiting, with reference to the various appended figures:

- Figure 1 shows an exploded perspective view of a first embodiment of a device for regulating a motor vehicle alternator according to the invention;

FIG. 2 represents an assembled view of the first embodiment of the device illustrated in FIG. 1;

FIG. 3 represents an exploded perspective view of a second embodiment of a device for regulating a motor vehicle alternator according to the invention;

FIG. 4 represents an assembled view of the second embodiment of the device illustrated in FIG.

Description of the Preferred Embodiments of the Invention

Identical elements, structure or function, appearing in different figures retain, unless otherwise specified, the same references.

With reference to FIGS. 1 and 2, the regulator device 100 of a motor vehicle alternator according to the invention comprises:

a brush holder support plate 10; - A circuit board 20 which is here a printed circuit board 20, called indifferently subsequently PCB or PCB. Note however that other standard substrates, different from the PCB, may of course also be used;

a protective cover 40 cooperating with a booster 50 forming a support adapted to raise the protective cover 40, the assembly forming protection means able to cover the printed circuit board 20.

The support plate 10 is made by plastic molding and incorporates (by overmoulding) only the conductive tracks, or traces, of the brush cage 12 and / or customer connectors 1 1 which will electrically connect the client connectors to the PCB 20.

The support plate 10 comprises a housing 14 forming a bearing surface for receiving the PCB 20. Advantageously, the geometry of the housing 14 and the geometry of the PCB 20 are adapted so that the PCB 20 can be used. self-position in the housing 14 during assembly of the PCB on the support plate 10.

The PCB 20 is held in position on the support plate 10 by conventional fastening means, such as for example gluing means, screwing means, clipping means or any other means for securing a PCB on a plastic support. The positioning of the PCB on the support plate 10 can be facilitated by the presence of pins on the support plate 10 cooperating with holes present on the PCB 20.

The support plate 10 also comprises a cavity 13 adapted for fixing a radiator-type cooling element, which will serve to cool at least one electronic component 60, of integrated circuit type, connected to the PCB 20.

The PCB is made according to the desired circuit and comprises for this purpose a plurality of conductive tracks.

The PCB 20, for example by its multilayer copper, allows to adapt to all applications with all predefined crosses and can support discrete components. Discrete components are surface mounted (Surface Mounted Device (SMD) or Surface Mounted Device (SMD) in English). The discrete components used on such a PCB are for example: resistors, capacitors, varistors, filters, chokes, diodes, transients, etc.

The PCB 20 comprises conductive tracks 21, called brush holder conductive tracks, adapted to be connected to the traces of the customer connectors 1 1 by means of metal wires 25, such as aluminum son. Such links are shown in Figure 2.

According to this first embodiment of the invention, the PCB 20 comprises conducting, phase 22, and grounding paths 22 located at the periphery of the PCB 20.

The PCB 20 also has a cavity 23 adapted to receive the integrated circuit 60, the cavity 23 being located opposite the cavity 13 of the support plate 10 when the PCB 20 is in position on the support plate 10. Near the cavity 23, the PCB 20 has conductive tracks 24 adapted to be electrically connected via aluminum wires 25 to said integrated circuit 60 positioned at the central location of the cavity 23.

The entire electrical circuit (PCB 20, conductive tracks, customer connectors 1 1, integrated circuit 60) is covered, with the exception of the conductive tracks 22 of supply, phase and grounding, by the protective cover 40 cooperating with the booster 50. The protective cover 40 is adapted to be housed in a peripheral recess 51 around the perimeter of the booster 50 so as to provide the upper surface of the booster 50.

The booster 50 thus makes it possible to provide a space between the PCB 20 and the top cover 40 so as to be able to incorporate a gel or a resin to seal the electrical circuit.

In non-limiting embodiment, the protective cover 40 is glued or clipped onto the booster 50 which is itself secured to the PCB 20 and / or the support plate 10 by conventional fastening means, for example by gluing, clipping, screwing, etc. The device 100 may also comprise sealing means positioned at the bearing surface between the support plate 10 and the booster 50.

The regulator device 200 of a motor vehicle alternator illustrated in FIGS. 3 and 4 is identical to the regulator device 100 described in FIGS. 1 and 2 with the exception of the characteristics which will be described later. In this second exemplary embodiment, the protection means 150 are formed by a single covering shell comprising both a thick peripheral portion forming an elevation and an upper surface forming the protective cover by providing a space between the PCB. 20 and the upper surface of the shell 150. In this embodiment, it is not necessary to add a gel or resin to seal the electrical circuit.

According to a third embodiment (not shown), the conductive supply, phase and grounding tracks can be directly overmolded on the support plate 10 and formed by metal traces. In this case, it will be necessary to provide connection means between the metal traces and the PCB. This particular embodiment has the advantage of improving the pressure resistance of the supply, phase and ground tracks which are subjected to clamping stresses.

According to a fourth embodiment (not shown), the conductive supply, phase and grounding tracks and / or the brush-carrying conductive tracks 21 of the PCB are overmolded.

Claims

Device (100, 200) for regulating a motor vehicle alternator comprising a brush holder support plate (10) of plastics material; said device (100) being characterized in that it comprises a circuit board (20) forming the electric circuit of said regulator, said circuit board (20) being secured to said brush holder support plate (10) and having an opening (23) for receiving an integrated circuit (60) connected to said circuit board (20) by electrical connections (25).

Device (100, 200) for regulating a motor vehicle alternator according to the preceding claim, characterized in that said circuit board (20) is a printed circuit board called PCB.

Device (100, 200) for regulating a motor vehicle alternator according to the preceding claim, characterized in that it comprises protection means (40, 50, 150) adapted to cover said circuit board (20) and positioned in pressing on said brush holder support plate (10).

Device (100, 200) for regulating a motor vehicle alternator according to one of the preceding claims, characterized in that said protection means (40, 50, 150) are arranged so as to provide a space between said circuit board (20) and said protection means (40, 50, 150).

Device (100, 200) for regulating a motor vehicle alternator according to one of the preceding claims, characterized in that said space is filled by sealing means such as a gel or a resin.

6. Device (100, 200) for regulating a motor vehicle alternator according to one of the preceding claims, characterized in said device (100) comprises sealing means positioned between said protection means (40, 50, 150) and said circuit board (20). 7. Device (100, 200) for regulator of a motor vehicle alternator according to one of the preceding claims characterized in that said circuit board (20) is formed by conductive tracks adapted to receive discrete components. 8. Device (100, 200) for a regulator of a motor vehicle alternator according to one of the preceding claims characterized in that said circuit board (20) comprises conductive tracks brush holder (21) adapted to connect said card (20) to connectors (1 1) of said brush support plate (10).

9. Device (100, 200) for a regulator of a motor vehicle alternator according to the preceding claim characterized in that said brush holder conductive tracks (21) are electrically connected by welds of aluminum wire (25).

10. Device (100, 200) for regulator of a motor vehicle alternator according to claim 8 or 9 characterized in that said brush holder conductive tracks (21) are overmolded. 1 1. Device (100, 200) for regulating a motor vehicle alternator according to one of the preceding claims, characterized in that said circuit board (20) comprises electrical connections with the electrical machine forming the alternator, said links being integrated in the brush holder with overmolding or without overmolding;

Regulator for a motor vehicle alternator characterized in that it comprises:

a regulator device (100, 200) according to one of the

preceding claims; an integrated circuit (60); and

- a radiator

13. Alternator of a motor vehicle characterized in that it comprises a regulator according to claim 12.