The present invention relates to a voltage regulator with a brush holder for a rotary electrical machine, in particular an alternator or an alternator-starter of a motor vehicle, and a rotary electrical machine comprising an assembly of this type.
In the prior art, many rotary electrical machines are equipped with a current rectification device and a voltage regulator assembly with a brush-holder. For example,
The number of phases depends on the applications, and can be more than three, as described for example in document WO 03/009452, one or two rectifier bridges being able to be provided. The rotor in
A cylindrical core, which in this case is in two parts, is interposed axially between the flanges of the wheels 7, 8. This core supports an excitation coil 101 on its outer periphery.
The shaft 3 of the rotor 2 supports on its front end a drive unit, such as pulley 112 belonging to a movement transmission device with at least one belt between the alternator and the thermal engine of the motor vehicle, and, on its rear end 13, with a reduced diameter, it supports collector rings which are connected by wired connections at the ends of the excitation coil of the rotor. The wired connections and the collector rings in this case belong to an added-on collector of the type described in document FR 2 710 197. Brushes (with no reference) belong to a brush-holder, and are arranged such as to rub on the collector rings. The brush-holder is connected to a voltage regulator, in order to form with the latter a voltage regulator with a brush-holder 14. The voltage regulator regulates the voltage of the alternator, in order to protect the consumers, and to recharge the battery to the correct voltage.
In all cases, when the excitation coil 101 is supplied electrically via the brushes or without them, the rotor 2, which is made of ferromagnetic material, is magnetised, and becomes an inductor rotor with formation of magnetic poles at the teeth of the magnet wheels.
This inductor rotor creates an alternating induced current in the induced stator when the shaft 3 rotates, with the rectifier bridge(s) of the current rectification device 25 making it possible to transform the induced alternating current into a direct current, in particular in order to supply the charges and consumers of the on-board network of the motor vehicle, as well as to recharge the battery of the said vehicle. In
In these two embodiments, a perforated protective cover is provided surrounding the voltage regulator and the current rectification device 25. This cover has the reference 31 in
The flanges 116 and 50 are known in a conventional manner respectively as the front bearing 116 and the rear bearing 50. They form a housing. These bearings 116, 50 in this case have a hollow metal form, and are for example based on aluminium, which makes it possible to obtain the required form by moulding. These bearings are connected electrically to the earth of the vehicle via lugs with no reference which they comprise for securing of the alternator on a fixed part of the vehicle.
They each support centrally a ball bearing, respectively 19 and 20, for fitting with rotation of the shaft 3 of the rotor 2. A brace 159 is in this case interposed between the rotor 2 and the bearing 19, which has a diameter larger than that of the bearing 20.
In
The current rectification device, which is supported by the rear bearing, or as a variant by the front bearing, comprises a plurality of positive diodes 20 supported by a positive support, a plurality of negative diodes supported by the base of the bearing, and a connector in order to connect the diode tails to the outputs of the phases of the stator. The diodes constitute current rectification elements. According to another embodiment these are replaced by transistors of the MOSFET type.
The positive support and the bearing are made of metal, whereas the connector comprises a body made of plastic material in which there are embedded electrically conductive tracks which are stripped in some locations in order in particular to form the electrical connections with the tails of the positive and negative diodes.
As can be seen in particular in FIG. 5 of this document WO 03/009452, the diodes extend parallel to the axis of the alternator, and the connector is implanted radially above the positive support which is electrically insulated by the rear bearing.
This arrangement is not entirely satisfactory. In particular, the fitting of the components in the voltage regulator with a brush-holder is complex and costly.
The objective of the present invention is thus to eliminate this disadvantage by means of an improved voltage regulator assembly with a brush-holder.
The subject of the invention is a voltage regulator assembly with a brush-holder for a rotary electrical machine designed for a motor vehicle, which assembly comprises:
According to a general characteristic, the voltage regulator assembly with a brush-holder comprises two parts:
Assembling these first and second parts provides an assembly which includes the brush-holder and the microcontroller.
According to one embodiment, the said assembly comprises at least one slide so that the first part which forms a central part slides relative to the second part according to the said first axis.
By means of this slide connection, the first part and the second part are easily assembled, after having added the brushes and the microcontroller respectively.
According to one embodiment, the slide connection comprises at least one rail for guiding the second part and studs of the first part, each of the said studs cooperating with a guide rail.
According to one embodiment, the first part comprises closure walls, each of the closure walls being supported on a guide rail of the second part in a direction transverse to the said guide rail, in order to stop it up.
This prevents water from being able to infiltrate via the guide rail after fitting of the first part on the second part.
According to one embodiment, the receptacle for receipt of the brush-holder comprises at least two ridges, and the second part comprises semi-cylindrical guides, with the said two ridges cooperating with the two semi-cylindrical guides in order to permit guiding of the first part relative to the second.
This therefore permits the fitting of the first part on the second part.
According to one embodiment, the second part comprises a receipt receptacle in which the first part is fitted in order to form the said body.
In cooperation with the receptacle designed for the brush-holder 201, the fitting of the first part within the receipt receptacle permits a significant improvement in the sealing of the brushes.
According to one embodiment, the receipt receptacle comprises two ends which extend projecting in the direction of the first part, and the said two ends cooperate with two projections of the first part, such that the first part can be inserted between the said two ends.
This permits the fitting and removal of the first part relative to the second part. This provides firstly durable securing, and secondly, in the case of a replacement, only the one of the two parts which is defective needs to be replaced.
According to one embodiment, the first part comprises two faces perpendicular to the said second axis (y1-y2) and two first walls which extend projecting according to the said first axis in the direction of the second part from the said two faces, the said receipt receptacle comprises two second walls which delimit it, the said two second walls extending according to the said first axis in the direction of the first part, and each of the first walls co-operates with one of the said second walls.
This improves further the sealing within the receipt receptacle.
According to one embodiment, each of the first walls has an axial length which is sufficient to cover one of the said second walls at least partly.
According to one embodiment, at least one of the two faces has an additional thickness.
The retention of water in this area is limited. In fact, the water stored could eventually infiltrate towards the receipt receptacle.
According to one embodiment, the additional thickness comprises a damming part in the form of an “L” covering the first wall, the said damming part being formed by a first longitudinal part extending according to the said first axis (z1-z2) and a second part extending according to the said second axis (y1-y2) in the direction of the second wall with which the said first wall co-operates.
The retention of the water in this area is limited more efficiently by forming a dam which prevents the water from infiltrating.
According to one embodiment, the second part comprises a separation wall which extends according to the second axis (y1-y2), with the said separation wall separating the receipt receptacle into two receipt sub-receptacles with an equivalent volume.
This therefore prevents short-circuiting between the two brushes, with one sub-receptacle being dedicated to each brush.
According to one embodiment, the second part is superimposed by a seal extending according to the said second axis, with one of the ends of the seal being supported on one of the second walls.
The sealing is improved for the components which are accommodated within the second part, in particular the microcontroller and the smoothing capacitors.
According to one embodiment, the first part comprises a first excitation terminal comprising a stud which extends according to the first axis (z1-z2), and the second part supports on one of the two ends a second excitation terminal, the said second terminal being provided with a guide groove for cooperation with the said stud, in order to facilitate the relative positioning of the first terminal in relation to the second terminal.
According to one embodiment, the said assembly comprises a heat dissipation plate, wherein the second part comprises an inner face facing towards the first part and an outer face facing towards the other side, with the said outer face extending on a plane perpendicular to the first axis (z1-z2), and wherein the outer face is formed at least partly by the said dissipation plate.
The dissipation plate thus forms a substantial surface area of the outer face, which improves the cooling of the components of the second part, in particular the microcontroller and the smoothing capacitors.
According to one embodiment, the microcontroller is accommodated in the second part, such that it comes into thermal contact, for example in accordance with its largest surface area, with the heat dissipation plate.
For example, the voltage regulator assembly with a brush-holder comprises a smoothing capacity of the battery terminal to which the electrical machine is connected, and the capacitor extends according to the first axis (z1-z2) in order to reduce the size of the voltage regulator assembly with a brush-holder according to the second axis (y1-y2).
The invention also relates to a rotary electrical machine comprising a housing provided with cooling windows, with a rotor which is accommodated in the said housing being able to rotate around an axis of rotation (X-X) and to blow air discharged by the said cooling windows, the said rotor being provided with collector rings in order to receive an excitation current.
According to a general characteristic, the machine comprises a voltage regulator assembly with a brush-holder as previously described, the brushes of the said assembly being in electrical contact with the said collector rings.
According to one embodiment, the voltage regulator assembly with a brush-holder is fitted on the housing accommodated within a protective cover fitted on the housing, and the machine comprises a closure ring arranged between the housing and the protective cover, in order to prevent the input of the air discharged by the cooling windows.
According to one embodiment, the protective cover is provided with an opening for the intake of cooling air, with the said opening being delimited by two vertical walls of the protective cover, such that the cooling air is guided towards a face of the voltage regulator assembly with a brush-holder, which face faces towards the exterior of the machine and extends on the plane perpendicular to the said first axis (z1-z2).
For example, the cooling air is thus guided towards the dissipation plate, in order for it to be cooled by convection.
The invention will be better understood by reading the following description and examining the figures which accompany it. These figures are provided purely by way of illustration, and in no way limit the invention.
For this purpose, the voltage regulator assembly with a brush-holder comprises in particular (not shown in
The voltage regulator assembly with a brush-holder 100 also comprises a body made of electrically insulating material which is globally in the form of a “T” and comprises two parts:
The part 200 comprises a third axis x1-x2 which coincides with the axis X-X in
For example, the first part comprises two faces 212 perpendicular to the second axis (y1-y2) and the first protuberance is a first excitation terminal 209 attached to the face 212 situated on the y1 side. According to one embodiment, the first part also comprises two faces perpendicular to the third axis (x1-x2) and the second protuberance is a locating pin 210 which is attached to the face perpendicular to the third axis on the x1 side.
The two faces 212 and the two faces perpendicular to the third axis (x1-x2) can form a receptacle 201 in order to receive the brushes.
For example, at least one of the two faces 212 has an additional thickness 207 at its junction with one of the first walls 205. According to this example, the additional thickness 207 can comprise a damming part 213 in the form of an “L” which covers the first wall 205. The part 213 is formed for example by a first longitudinal part which extends according to the said first axis (z1-z2) and a second part which extends according to the said second axis (y1-y2) in the direction of a wall of the second part 300.
The first part 200 also comprises two projections 204, each being situated on a face 212. In addition, the first part 200 can comprise two first walls 205 which extend projecting according to the first axis (z1-z2) in the direction of the second part 300, starting from the said two faces 212. According to one embodiment, the first excitation terminal 209 comprises a stud 206 which extends according to the first axis (z1-z2). The first part 200 can also comprises closure walls 211. The first part 200 can additionally comprise at least one stud 203. For example, the first part comprises two studs, each being situated on a face 212. According to this example, the studs extend according to the first axis (z1-z2). The receptacle 201 can comprise two ridges 202. Finally, the face which is perpendicular to the first axis (z1-z2) and is situated on the second part side can be provided with a groove 208 according to the second axis (y1-y2), with the groove separating the said face into two.
The projections 204, the first walls 205, the stud 206 of the excitation terminal 209, the closure walls 211, the stud 203, the two ridges 202 and the groove 208 are configured to cooperate with the second part 300, as described hereinafter with reference to
The second part extends mainly in a direction of the second axis (y1-y2). In other words, the longest length of the rectangular parallelepiped of which it has the form is that according to the axis (y1-y2). For example, the aforementioned first protuberance which extends from a face perpendicular to the second axis (y1-y2) is a terminal 314 for connection to the potential B+ of a battery of the motor vehicle. It is situated on the y2 side.
For example, the aforementioned second protuberance which extends from a face perpendicular to the second axis (y1-y2) is a phase terminal 313 which is connected to one of the phases of the coil of the stator. According to this example, it can be situated on the y1 side. The phase terminal is used to receive the signal of a phase obtained from the windings of the electrical machine.
According to one embodiment, the signal obtained from this phase terminal is used to activate the regulator. Thus, when the machine is rotated by the thermal engine, the remanent magnetic field generates an electromagnetic force on the said phase. This electromagnetic force is compared with a threshold, exceeding of which activates the operation of the regulator. In other words, this corresponds to detection of the fact that the alternator is being driven, and that regulation of the voltage must be put into operation.
The second part 300 also comprises an earthing terminal 310 connected to the earth of the rotary electrical machine, and a communication terminal 311 designed to be connected to a computer of the motor vehicle.
According to one embodiment, the second part 300 comprises at least one guide rail 303, with each of the said studs 203 of the first part cooperating with a guide rail 303 in order to form a slide connection. According to this slide connection, the first part 200 forming the central part slides relative to the second part 300 according to the said first axis (z1-z2). In addition, if applicable, each of the closure walls 211 of the first part 200 is supported on a guide rail 303 of the second part 300 in a direction transverse to the said guide rail, in order to stop up the guide rail.
According to one embodiment, the second part 200 comprises two semi-cylindrical guides 302, in order to permit guiding of the first part 200 relative to the second part 300 by cooperation with the two ridges of the receptacle 201.
The second part 300 can comprise a receipt receptacle 301 in which the first part 200 fits in order to form the body of the voltage regulator assembly with a brush-holder 100. Advantageously, the receipt receptacle 301 comprises two ends forming clips 304 which extend projecting in the direction of the first part 200. Thus, the two ends which form clips 304 cooperate with the two projections 204 of the first part, such that the first part 200 can be inserted between the said two ends which form clips 304.
According to one embodiment, the second part 300 comprises a separation wall 308 which extends according to the second axis (y1-y2), with the said separation wall separating the receipt receptacle 301 into two receipt sub-receptacles with an equivalent volume.
As can be seen in
According to one embodiment, the receipt receptacle 301 comprises two second walls 305 which delimit it. The two walls extend along a plane perpendicular to the second axis (y1-y2). In particular they extend according to the first axis (z1-z2) in the direction of the first part. Each of the second walls co-operates with each of the first walls, as can be seen in
According to an embodiment shown in
It will be noted that, in the different embodiments of the invention and according to the applications, the addition of a sealing material such as resin or gel may be advantageous, as a complement to the means described, in order to prevent the penetration of water.
In addition, as shown in
As can be seen in
In addition, the second part 300 can also comprise smoothing capacitors 315 and 316. The capacitor 316 is a smoothing capacitor of the terminal B+ of the battery. For example, the capacitor extends according to the first axis (z1-z2) in order to reduce the size of the voltage regulator assembly with a brush-holder according to the second axis (y1-y2).
The machine illustrated in
Firstly, it comprises the voltage regulator assembly with a brush-holder 100 which is fitted on the housing 50 inside the protective cover 31. The outer face 320 of the second part 300 of the voltage regulator assembly with a brush-holder 100 can be seen, as well as the dissipation plate 319 in contact with the microcontroller 312. The brushes 215 of the said assembly 100 are in electrical contact with the aforementioned said collector rings 13, in order to emit an excitation current there.
Secondly it comprises a closure ring 198 arranged between the housing 50 and the protective cover 31, in order to prevent input of the air discharged by the cooling windows 199.
Thirdly, it comprises an opening 197, which is delimited on the axis x1-x2 side by a contour 195, and on the other side by a contour 196. This opening 197 permits the intake of cooling air which passes through the protective cover in order to reach the inside of the housing 50.
Number | Date | Country | Kind |
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1562277 | Dec 2015 | FR | national |
Filing Document | Filing Date | Country | Kind |
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PCT/FR2016/053346 | 12/13/2016 | WO | 00 |