Title of Invention

"A PROTECTIVE COVER PLATE OF ELECTRICALLY INSULATING MATERIAL"

Abstract A protective cover plate (100) of electrically insulating material, adapted to be mounted on the rear bearing plate (14) of a polyphase rotary electrical machine of the type comprising, an external carcass (13, 14) having said rear bearing plate (14) and carrying a wound polyphase stator (8), the phase outputs of which are connected to a phase connector (102) which is adapted to be connected to an external electronic module, and a support structure in an electrically insulated material, which is fixed on the rear bearing plate (14) and which carries the phase connector (102), characterised in that the cover plate (100) is so configured as to accomplish, at the same time, the functions of supporting the phase connector (102) and of covering the rear bearing plate (14).
Full Text The present invention relates to a protective cover plate of electrically insulating material.
This invention relates to a protective cover plate which is adapted to be mounted on the rear bearing plate of a polyphase rotary electrical machine, especially an alternator or an alternator-starter for a motor vehicle.
STATE OF THE ART
Rotary electrical machines are known, which are of the type comprising an external carcass having a front bearing plate and a rear bearing plate, a rotatable rotor shaft mounted in the front and rear bearing plates of the carcass, a rotor supported by the said shaft and provided with: an excitation winding which is connected through electrical connections to two slip rings carried by the rear end of the shaft; a wound stator surrounding the rotor and having a plurality of phases, the outputs of which are connected to a phase connector for connection to an external electronic module; a phase connector support of an electrically insulating material, which is fixed on the rear bearing plate; and a cover plate which is fixed on the rear bearing plate, and which covers at least one brush carrier, the brushes of which are arranged to engage on the slip rings fixed . to the rear end of the shaft of the rotor, which are connected to at least one excitation winding of the rotor.
In this machine, the cover plate covers the support of the phase connector, which is monobloc with a brush carrier containing the brushes in engagement against the said slip rings, and with a brush carrier connector for connecting the brushes to the electronic module, which includes a device for rectifying the alternating current from the wound stator.
Such a machine is described in the document WO01/69762.
Figure 1, which reproduces Figure 1 of the said document, while, however, omitting reference signs relating to parts and components which are not necessary for an understanding of the invention, shows a protective cover plate 17, which covers the rear bearing plate 14 and which , with the latter, covers the brush carrier denoted 16, the brushes of which are mounted so as to be applied against the slip rings 6 and 7, which are connected
through wire connections to the excitation winding as explained in the document WO01/69762.
The cover plate is fixed to the rear bearing plate. The brushes are connected electrically to a voltage regulator which is mounted on the outside of the machine. In this case, the voltage regulator is part of the electronic module, which is an electronic command and control module. More precisely, the rotary electrical machine being in this case an alternator-starter, the electronic module comprises a power module which includes the rectifying device, and a module for control and interfacing with the on-board wiring network of the vehicle and/or with the control module of the engine of the vehicle. This control module, in particular, manages the power functions in the alternator and starting modes, regulation in the alternator mode, and the transition from the starting mode to the alternator mode, in another version, where the machine is an alternator, the electronic module is simplified, because the control module does not have to manage the function of transition from the starting mode to the alternator mode; the machine is then working only in the alternator mode. The rectifying device of the power module may in that case consist only of diodes.
Figure 1 also shows the shaft 3 of the machine, the claw-type rotor 4, which is rotatable with the shaft 3 and which carries the excitation winding between its two pole wheels, the stator 8, the front bearing plate 13, and a rear fan 42 and front fan 43 which are rotatable with the rotor 4.
In a further version, the rotor has projecting poles and includes a plurality of excitation windings, as described for example in the document WO02/054566, and as mentioned in the above mentioned document WO01/69762. In a modified version of the machine, it is cooled by fluid flow; at least one of the two bearing plates 13 and 14 is hollow for flow of a fluid therein, for example the engine cooling fluid of the vehicle. The presence of the fans is not essential. In a modified version, only the rear fan is present.
This machine has an axial axis of symmetry (not given a reference numeral in Figure 1) which is coincident with the axis of the shaft 3, and which defines the axis of rotation of the rotor and the radial and axial directions of the machine. The front bearing plate 13 and rear bearing plate 14 are connected together for example by stretchers, one of which can be seen in Figure 1, in order to constitute an external carcass which is arranged to be mounted on a fixed part of the motor vehicle. This carcass serves to contain and support the stator 8 and rotor 4.
To this end, the carcass carries the stator 8 fixed to its outer periphery, and carries the shaft 3 mounted rotatably in its centre. For this purpose, the bearing plates 13 and 14 each carry a central ball bearing for the
rotatable mounting of the shaft 3, the front end of which carries a pulley which is arranged to be connected through a transmission device of the bolt type to the engine of the motor vehicle, while the rear end of the shaft 3 carries the slip rings 6 and 7. The bearing plates 13 and 14 have at their outer periphery an annular, axially oriented, skirt portion, each of which has a change of internal diameter at its free end for the axial location and centring of the body of the stator 8, interposed between the free ends of the skirt portions of the bearings 13 and 14.
The stator 8 accordingly comprises a grooved body which conventionally consists of a stack of laminations carrying armature windings, which extend through the body of the stator in grooves of the latter so as to project axially on either side of the body, whereby to define a front chignon and a rear chignon which partially surround, respectively, the front fan 43 and rear fan 42, so as to be cooled by the fans. The number of armature windings depends on the number of phases of the electrical machine. The windings are connected in the known way by winding in the grooves of the stator body of an electrical wire or bars, which are for example configured in a U shape, the ends of the branches of which are for example connected by soldering to constitute the winding.
In a known way, the rear chignon carries outputs, called phase outputs, which extend through the rear bearing via apertures in the latter, as can be seen in respect of both of them, for example, in the lower part of Figure 1a of the document EP-A-2 10090, whereby they are connected in a manner described below to a phase connector via the connection inputs of the phases and electrical tracks.
The machine shown is an alternator-starter which includes means for following the rotation of the rotor 4. These means are of the magnetic type, and comprise a target 50 for radial reading, which is carried by a target carrier of a kind known per se but not shown, together with sensors
52 which are carried by a sensor carrier shown at 53. The sensor carrier
53 has at least one projecting portion extending through an aperture in the rear bearing plate 14, for locating the sensors 52 in facing relationship with the target 50 and for radial reading of the latter. The sensor carrier is carried by the rear bearing 14, being in contact with the rear face of the bearing plate 14. As can be seen in Figure 2, the sensor carrier 53 carries two ears having oblong holes (not given reference numerals) for its angular adjustment; it is held against movement by means of washers and nuts which are screwed on to studs mounted in the rear bearing plate 14, one of which can be seen in Figure 1, and which pass through the oblong holes. The sensor carrier 53 is thus fastened by screw fastening between the bearing plate 14 and the washers on which the nuts bear.
In the phase protection and support means which includes the cover plate 17 and the phase support device as disclosed in the document
WO01/69762, the brush carrier and the sensor carrier each include a connector for connecting, respectively, the brushes and the sensors to the electronic command and control module fitted on the outside of the machine, and more precisely to the voltage regulator which governs the excitation winding of the rotor 4, and to the rectifying device for the alternating current produced by the wound stator of the alternator starter when the latter is working in the generator mode; the said device and the voltage regulator are part of the electronic module, as mentioned above.
Thus, the connector for the sensors 52 carried by the sensor carrier 53 is shown at 257, while the connector for the brush carrier 16 is shown at 162. The electrically conductive tracks which are encapsulated within the sensor carrier 52, which is of insulating material, connect the connector 257 to the sensors 52. As is shown in Figure 8 of the above mentioned document, the connector 162 for the brush carrier 16 is mounted on a support designated by the reference numeral 160, of an electrically insulating material, which is in the general form of a disc and which is fixed on the rear bearing plate 14 by means of two studs. Figure 2, attached hereto, reproduces the said Figure 8.
At the periphery of the support in this Figure, there can be seen three inputs for connection of the phases designated by the reference numerals 163, 164 and 165, each of which is arranged to receive, fixed to it, a phase output of the stator windings, which in this example are of the three-phase type. These inputs are connected, through electrically conductive tracks which are encapsulated within the support 160, to first electrical contact surfaces 166 to 168. The surfaces 166 to 168 are arranged on a projecting portion of the support 160 and form part of a first connection sub-assembly 161 which is called a phase connector for simplicity, so that an electrical phase connection device of the stator is formed which consists of the phase connector, the electrically conductive tracks and the connection inputs of the phases.
A second sub-assembly with complementary electrical contact surfaces, in this example of the male type, is arranged to be mounted on the connector 161, which in this example is of the female type, so as to constitute a first connector which links together the phases of the stator with the external electronic command and control module, via electrical cables and a second connector, which is of the same type as the first connector and which comprises a second phase connector partly carried by the electronic module. The assembly consisting of the first connector, the cables and the second connector constitutes an electrical device for connection between the machine and the electronic module,
The first connector is described in more detail in the document FR-2 819 943. For more detail, reference should be made to the two prior art documents mentioned above.
In the protection and support means for the phase connector of the rotary electrical machine of the known kind, the second sub-assembiy of the first phase connector is connected axially on the projecting element of the support 160, and the cables which go to the electrical module are oriented in the radial direction of the machine, at the output of the second subassembly, the position of which is dictated by the projecting element of the support 160. This projecting element is close to the brush carrier 16.
Now, in some applications it would be preferable to bring the cables out in another way, for example because of size considerations, which in particular are linked to the presence of components or partition walls adjacent to the machine.
OBJECT OF THE INVENTION
The object of the present invention is to propose a solution to this problem. With this end in view, the cover plate according to the invention is characterised in that it is so configured as to perform the function of supporting the phase connector and at the same time covering the rear bearing plate.
Thanks to the invention, there is considerable latitude in the positioning of the phase connector, and the cover plate ensures a double function, which enables the brush carrier to be simplified. The phase connector is able to be circumferentially spaced away from the brush carrier, and this is so in spite of the presence of the sensor carrier.
This variable positioning of the phase connector with respect to the brush carrier enables the connecting cables to be passed into the free space, according to the application.
For example, where the base of the cover plate is axially close to any component or partition, the phase connector is oriented in a direction which enables radial access to be obtained to the phase connector, that is to say generally at right angles to the phase connector of the prior art, so that the cables are able to extend axially or in an inclined direction, and so that the axial size of the machine equipped with the first connector is reduced.
The phase connector, in one embodiment, projects with respect to the outer periphery of the cover plate. It is oriented in the radial or axial or tangential direction of the machine. In a modified version, the phase connector is inclined with respect to the axial direction of the machine. It is accordingly possible to obtain axial or radial or combined access to the phase connector in a place where there is room.
In this kind of embodiment, the phase connector extends either so as to project beyond the outer periphery of the rear bearing plate, or so as to lie behind this outer periphery; the choice depends on the application and on the amount of space available.
In another embodiment, the phase connector is mounted within the thickness of the cover plate.
In a further modified version, it projects axially with respect to the cover plate, being for example carried by the base of the cover plate.
Thanks to the invention, because it is possible to space the phase connector away from the brush carrier, and because there is therefore no inconvenience from dimensioning problems, the size of the projecting element of the phase connector can be increased, so that the machine is able to have more phases. Thanks to the invention, the phase connector can of course take some other form, for example the form described in the document GB-2 354 641A.
The invention enables space to be made available within the cover plate, so that the brush carrier and voltage regulator can be combined in one assembly.
The invention is applicable to a conventional alternator not having a sensor carrier.
Within the scope of this Application, the phase connector can be located radially further in, in the space which is made available by the sensor carrier.
According to a feature of the invention, the phase connector of the stator is disposed at the outer periphery of the cover plate, and is supported by a projecting structure in the form of arms projecting from the cover plate.
This arrangement enables a support lug, fixed to a fastening shank of the said connector, to be passed between the arms. This lug is arranged to be fixed, for example by screw fastening, on the rear bearing plate so that a robust phase connector is obtained, in particular when the second subassembly of the first connector is being fitted.
In a modified version and in accordance with one feature of the invention, the phase connector is located by the projecting structure, in this case by the support arms, at a position beyond the outer periphery of the cover plate.
This arrangement facilitates access to the connector, particularly in the radial direction.
According to yet another feature of the invention, the phase connector is connected to connecting inputs of the stator phase outputs, for example in the form of fastening lugs for the phase outputs, by electrically conductive tracks which are encapsulated at least partly within the projecting structure, for example in the support arms; the cover plate is made of an electrically insulating material. In a further modified version, the electrically conductive tracks are extended and are carried by the base and/or the outer periphery of the cover plate. The phase connection inputs in one embodiment lie at the outer periphery of the cover plate.
Thus, the cover plate has an additional function of protecting the electrical tracks. It will also be appreciated that the electrical tracks stiffen the cover plate and the arms. In a further modified embodiment, where the number of contact tracks or strips is greater than three, the support lug is omitted.
In a still further modified version, the electrical tracks are replaced by electrical conductors, which are for example of circular, rectangular or oval cross section, such as electric wires at least partly encapsulated in the projecting structure and/or the cover plate.
Some part of the electrical tracks is, in another modification, replaced by electrical wires. All combinations are possible.
It will also be appreciated that the position of the lugs for fastening the phases, or in general terms the phase connection inputs of the stator, can vary as a function of the application, and in particular as a function of the space available. The electrically conductive tracks may be carried by the base and/or the skirt portion and/or the projecting structure of the cover plate, which is of hollow form.
In yet another modified version, the projecting structure comprises a boss. More precisely, in one version, the two arms are replaced by a solid boss which is moulded integrally with the cover plate and in which the electrical tracks are encapsulated, as may also be the support lug, the presence of the latter being then no longer necessary in some applications.
In all cases, the form, orientation and location of the projecting structure enables the phase connector to be oriented in space, so that it will be in whatever is the most appropriate position.
According to a still further feature of the invention, the brush carrier connector is mounted on the base of the cover plate, being oriented radially or axially or in a combination of both.
According to yet a further feature of the invention, the brush carrier cortnector is made in one piece with the cover plate, which accordingly has a new function.
According to yet a further feature of the invention, the brush carrier connector is connected to the brush carrier through electrically conductive tracks, or any other form of electrical conductor such as electric wires, encapsulated in the base of the cover plate. These tracks stiffen the cover plate and enable the brush carrier to be standardised and simplified.
Thus, according to yet another feature of the invention, reducing the cost, the brush carrier is made in the form of a separate component which is mounted under the base of the cover plate, which thereby covers the brush carrier. The amount of material in the brush carrier is thus reduced, given that this material is more expensive, because of its function of guiding the brushes, than that of the cover plate. Because of these arrangements, in a modified embodiment, the cover plate is in two parts, namely a first part including the phase connector and the associated electrical tracks, and a second part including the brush carrier connector and the associated electrical tracks.
This form of embodiment leads to further standardisation. In this connection, the second part may be of a standard type while the first part is adaptable according to the application and the environment. Thus, the phase connector may be oriented axially or radially and/or both, and its location can be variable circumferentially. It is of course possible to do the opposite, and standardise the first part; the second part would then be adaptable.
According to still a further feature of the invention, for an alternator-starter including a sensor carrier and a sensor carrier connector, the sensor carrier is mounted under the base of the cover plate and the sensor carrier connector passes radially through an aperture in the external peripheral skirt portion of the cover plate.
In a modified version, the sensor carrier is integrated with the cover plate, which in this case preferably carries the three connectors, namely the phase connector, brush carrier connector and sensor carrier connector respectively. These connections may have access radially or otherwise, due in particular to the fact that the cover plate is of mouldable plastics material. One of the connectors may be inclined, with the others being generally radial; all combinations are possible according to the space available. At least one of the said connectors is of the female type in another modification.
In that case, the sensor carrier is preferably fixed against rotation: an electronic device is provided for adjusting the sensors in relation to the target.
In a further version, the brush carrier connector is of course not part of the cover plate; the brush carrier then carries its own connector.
Thus, where the cover piate is in two parts as mentioned above, the second part may be equipped with a standard brush carrier having an integrated connector.
BRIEF DESCRIPTION OF THE DRAWINGS
The invention will be better understood, and further objects, features, and details and advantages of it will appear more clearly, in the course of the following explanatory description which is made with reference to the attached diagrammatic drawings, these being given by way of example only and showing one embodiment of the invention, and in which:
- Figure 1 is a view in cross section of a polyphase rotary electrical
machine, equipped with means for supporting and covering the phases, in
accordance with the state of the art;
- Figure 2 is a view of a support for the electrical connections of the means shown in Figure 1;
- Figure 3 is a perspective view of a support and enclosure means for the phases of a polyphase rotary electrical machine according to the invention, in the state in which it is mounted on the rear bearing plate of the machine;
- Figure 4 is a perspective view of a cover plate according to the invention, for inclusion in a rotary electrical machine consisting of an alternator-starter;
- Figure 5 is a perspective view of the cover plate shown in Figure 4, showing it at the stage of manufacture, prior to in situ moulding, in which the electrically conductive tracks which are encapsulated within the cover plate are caused to appear;
- Figure 6 is a perspective view of a brush carrier according to the invention;
- Figure 7 shows the cover plate of Figure 4, completed by a cover element for protection of the lugs for fastening the phase outputs; and
- Figure 8 is a scrap view, in perspective and on a larger scale, of the detail indicated by the arrow VII in Figure 5.
DESCRIPTION OF PREFERRED EMBODIMENTS OF THE INVENTION
Figure 3 shows a first example of an embodiment of the protective cover plate of the invention, in the state where it is mounted on the rear bearing plate of a rotary electrical machine of the same type as that shown in Figure 1. In the case of Figure 3, the cover plate is adapted to be used for
an alternator-starter, to the extent that the rear bearing plate carries the sensor carrier as in Figure 2.
In Figure 3, the rear bearing plate carries the reference 14 already used in Figure 1. The cover plate is designated by the reference numeral 100, and the connector of the sensor carrier, adjustable circumferentially, has the reference numeral 106. The rear bearing plate, which in this example is of aluminium, is of the known hollow form, and, as can be seen in Figure 1, it has a base portion which is oriented transversely with respect to the axial axis of symmetry of Figure 1, and which is extended at its outer periphery by an annular flange in the form of an external peripheral skirt portion which is oriented axially and which is formed with air outlet holes (not given reference numerals) to allow air to escape. In Figure 3, this annular peripheral skirt portion carries the reference numeral 215. The base of the bearing plate 14 has air inlets which can be seen in Figure 1. The skirt portion 215 also has apertures which, in this case, are oriented axially (see Figure 3), so that in the known way, when the rotor of the machine is turning, an air flow is set up by the rear fan 42 of Figure 1 between the air inlets and air outlets, whereby to cool, in particular, the rotor and stator of the machine.
For this purpose, the hollow cover plate 100 has air passage holes, not given reference numerals and seen best in Figures 3 and 7. This perforated cover plate 100 has a generally transversely oriented base portion, which is extended at its outer periphery by a generally annular, axially oriented, peripheral skirt portion
In Figures 3 to 5 and Figure 7, the outer peripheral skirt portion, constituting a housing, and the base are given the reference numerals 115 and 117 respectively. The air flow holes mentioned above are formed in the skirt portion 115 and base 117, as can be seen in Figures 3 to 5 and Figure 7. These holes are oblong in the present case. Thus, the skirt 215 has oblong holes, oriented axially, while the base has oblong holes of circumferential or rectilinear form between the connectors 102 and 104 which are to be described below. In the left hand part of Figure 3, it can be seen that the bearing plate 14 has, in the known way, a projecting ear for fitting of the machine on a fixed part of the motor vehicle. In another version, the base of the bearing plate 14 is not cut away, because the machine is cooled by fluid flow.
The cover plate 100 is so designed as to carry out, at the same time, the function of the protective cover 17 and the function of the support 160 for the first connection sub-assembly 161 of the known device shown in Figure 2, in which these functions are performed by separate components.
In the first embodiment, the cover plate 100 defines a cavity within which the brush carrier 135 and the sensor carrier are mounted; this cavity is
closed by the base of the rear bearing plate 14, on which the protective cover plate is fixed, so that the latter thus covers the brush carrier and sensor carrier.
As can be seen in Figure 3, to this end the cover plate 100, which is made of an electrically insulating material and preferably of moulded plastics material, carries, projecting at its outer periphery, the two connectors that provide the connections to the external electronic command and control module, via cables and/or electrical wires which are not shown; namely the connector 102 which constitutes the first connection sub-assembly for the three phases of the stator, hereinafter referred to for convenience as the phase connector, and the brush carrier connector 104. The three said connectors 102, 104 and 106 are oriented outwardly with respect to the axis of the machine, and project with respect to the skirt portion 215 of the bearing plate 14. These connectors are grouped in a common zone, and are accessible radially from outside. They will be referred to as the radial connectors, for simplicity.
As can be seen in Figure 3, the cover plate 100 has an oblong, circumferential opening 151, in this example an aperture, for passage of the connector 106. It is therefore possible to obtain radial access to the connectors, given that the connectors 102 and 104 in this example are offset axially outwards with respect to the base 117 of the cover plate 100, that is to say outwards with respect to the outer face of the base 117. The skirt portion 115 in this example is not of annular form in the region of the connectors 102 and 104, each of which extends at right angles to the latter; the connector 102 is located further out than the connector 104.
In a modified version, the skirt portion 115 is annular in form at the level of the connectors, which then extend radially. The connector 102 projects outwards in the opposite direction from the axis of the machine with respect to the connector 104.
The phase connector 102 corresponds to the connector described in the documents WO01/68762 and FR 2 819 943. The phase connector includes the cylindrical projecting element which is now indicated by the reference numeral 108, and the three first electrical contact surfaces 109 to 111 disposed on this projecting element, together with a threaded portion 208 which serves for fastening of the second complementary subassembly (not shown) of the first connector. The connector 102 extends outwards as explained above, because its threaded portion 208 extends outwards away from the centre of the machine. The threaded portion 208 extends generally radially with reference to the radial direction of the rotary electrical machine, and is accessible radially from outside.
The number of contact surfaces depends on the number of phases in the alternator-starter. A minimum of two contact surfaces are provided
because the alternator-starter is of the polyphase type. In a modified version, this number is greater than three, because of the position of the phase connector spaced away from the brush carrier, as will be described below; this position enables the size of the projecting element 108, and therefore the number of contact surfaces, to be increased. Similarly, this position enables the phase connector to be configured in a different way, which may for example take the form described in the document GB-A-2 354 641, or any other form.
The connector 102 is located on a projecting portion of the cover plate 100 which, in this example, is in the form of support arms 113, extending radially outwards so that they are located at the outer periphery of the cover plate projecting generally radially from the peripheral external skirt portion 115 of the latter, and projecting from the skirt portion 215 of the bearing plate 14. As can be clearly seen in the drawings, there are two support arms 113 which are formed in one piece with the cover plate, in this example by moulding, being partly fixed to the transversely oriented base 117 of the cover plate and the external peripheral skirt portion 115.
By configuring the arms 113 suitably, it can be seen that it is possible to modify the axial position of the projecting element 108 and the threaded portion 208 which is in the form of a shank. It is also possible to bend the arms so as to go round an obstacle.
The two arms 113 carry at their end, which is accordingly on the outside of the outer periphery of the cover plate, a flange 112 which is oriented at right angles to the arm 113. The flange 112 therefore joins together the arms 113, and on its outer face it carries the projecting element 108 of the phase connector 102.
The projecting element 108, which is cylindrical in this embodiment, is in this example formed integrally with the arms 113, the flange 112 and the cover plate 100, inexpensively in thermoplastic material. The radially inner face of the support flange 112 carries a lug 121 for support and fastening to the rear bearing plate 14.
This lug 121 constitutes a means for fastening the projecting support structure that comprises the two arms 113 and flange 112 to the rear bearing plate 14. The lug 121 extends between the two arms 113 at right angles to the support flange, and is fixed with respect to the threaded portion 208, which is adapted to pass through the casing and the push on cover of the second complementary sub-assembly of the first connector, as described in the above mentioned document FR-A-2 819 943.
Figure 3 shows a chimney element 209 moulded integrally and projecting from the rear bearing plate, the free end of the chimney element serving for engagement with the lug 121, which is formed with a hole for the
passage through it of a fastener for securing the lug to the chimney element 209. In this example, this fastener consists of a screw which is threaded into a thread formed in the chimney element 209 at its free end. In another version, the fastener is a rivet. The connector is thus robust, because, during fastening of the second connecting sub-assembly of the first connector by threading of a nut on the threaded portion 208 in the form of a shank, the said portion 208 and the projecting element 108 are well supported.
More precisely, the lug 121 is integral with the threaded portion 208, and replaces the head of the screw in the prior art. The lug 121 has, as is best seen in Figure 8, a projecting portion in the region of its zone of connection with the first threaded portion 208. This projecting portion is in the form of a washer which has two flats for indexing circumferentially the assembly consisting of the threaded portion 208 and lug 121. For this purpose, the projecting element is engaged in a complementary rebate formed in the flange 112 and in the hollow projecting element 108. The base of this rebate is defined by a member which is formed with a hole for passage of the shank 208 through it. In this example, this member consists of a washer of thermosetting plastics material which is resistant to plastic flow. This washer is preferably attached on the inside of the projecting element 108 by the technique of in situ moulding, and serves as an abutment to the projecting portion of the lug 121.
The three electrical contact surfaces 109 to 111, which are arranged on the projecting element 108, are separated from each other by wings 123 which are arranged to penetrate into slots in the pressure zone of the second sub-assembly of the first connector, described in the above mentioned document FR-A-2 819 943, so as to prevent the said second sub-assembly from rotating. The threaded portion 208 extends through the projecting element 108, and through a sleeve to which the wings 123 are connected as can be seen in Figure 3. Each of the surfaces 109 to 111 is connected electrically to a phase input connection 125 in the form of a lug 125 for fastening to a phase output of the windings of the stator. This lug 125 is located at the outer periphery of the cover plate, in a zone spaced away from the connector. This electrical connection is achieved through electrical conductors which, in this example, are in the form of electrically conductive tracks 127 encapsulated within the cover plate. The tracks 127, the inputs 125 and the surfaces 109 to 111 are preferably of metal and are formed by a stamping and bending technique.
It will be understood that each track 127 comprises, firstly a portion 128 which is encapsulated mainly in the base 117 of the cover plate and, by bending, in the skirt portion 115 of the cover plate in the region of its terminal lug 125, and secondly, a portion 129 which is bent back with respect to the first portion 128 through an angle of 90°, so that it is then
encapsulated within a support arm 113. Figures 5 and 8 clearly show that two track portions 129 are moulded in situ within one arm 113, while the third portion is in the other arm. The free ends of the track portions 129 are so configured that they can be encapsulated within the support flange 112 and the projecting element 118, on the outer face of which they form the three electrical contact surfaces 109 to 111. The surfaces 109 to 111 extend at right angles to the axis of the shank 208. In another version, they extend at an inclination with respect to the axis of the threaded shank. In a further version, the surfaces 109 to 111 have a bowed form or a pointed form, being for example V-shaped, or again they may be in the form of a hollow member which may have a frusto-conical side wall. The second sub-assembly of the connector does of course have complementary electrical contact surfaces. All of these various versions enable the surface area of the electrical contacts to be increased. In yet another version, the shank 208 is replaced by a chimney element which may for example be frusto-conical, with lugs which are elastically deformable at their free end and which are in the form of fastening hooks for rapid snap-fastening of the second sub-assembly on the phase connector 102. In order to ensure more powerful contact, the shank is, in still another version, threaded on the inside or the outside for screwing the two sub-assemblies of the connector in place with the aid, respectively, of a screw or a nut. The snap-fitting then enables the two sub-assemblies to be pre-positioned.
In this case, the second sub-assembly includes a plate with an aperture through which the chimney element passes, the hooks on the chimney element engaging with the top face of the plate. The lower face of the plate includes the second electrical contact surfaces which are complementary to the surfaces 109 to 111. The second surfaces may be extended laterally so as to be connected to the wires of the electrical connecting cable.
It will be noted that the chimney element constitutes an internally hollow bar.
The fastening shank 208, whether of the threaded form or hollow with fastening hooks, extends through the flange 112 and serves for fastening the second sub-assembly of the connector.
The three surfaces 109 to 111 are offset circumferentially from each other, and are separated in the way described above by the insulating wings 123. It will be appreciated that the tracks 127 stiffen the arms 113 and the cover plate 100, the latter being of plastics material moulded in situ on the tracks 127. The position of the lugs 125 and the form of the tracks 127 can be adapted according to the application.
The lugs 125 are hollow, and they are generally C-shaped, although in another version they may be U-shaped, for the crimped fastening of the outputs of the phases of the stator. In another version, the lugs are solid, for soldered fastening of the stator phase outputs. In yet another version, the lugs are replaced by tongues or small ears. The phase input connectors 125 may take different forms, and, with the electrical connecting tracks 127 in the form of metallic strips, and the phase connector 102, they form part of a means for making electrical connection of the phases carried by the cover plate 100. It will be noted that the base 117 carries a wall (not given a reference numeral) for separating and electrically insulating two of the tracks 127.
In a further version, at least one of the portions 128 and 129 is replaced by electrical conductors, such as electric wires of circular, rectangular or oval cross section. For example, an electric wire connects the appropriate surface 109 to 111 to the associated lug 125. The wire is secured on the members 109 to 111 and 125 for example by soldering.
The brush carrier connector 104 is smaller in size than the structure consisting of the arms 113 and phase connector 102. The connector 104 is disposed on the base 117 of the cover plate 100, being made in one piece with the latter. This connector 104 is located away from the brush carrier, and projects at the outer periphery of the cover plate 100, so that it is accessible radially from outside.
As indicated earlier herein, it is oriented generally radially, and extends parallel to the phase connector 102. These connectors are located in the region of the passage opening 151 of the connector 106, so that they stiffen the skirt portion 115.
The connectors 102 and 104 are offset axialiy with respect to the connector 106, in the direction away from the bearing plate 14. The connector 106 is, in a modified embodiment, located circumferentially between the connectors 104 and 102.
The connector 104 includes two markers 131, each for an electrical potential, which are oriented radially, and each of which is electrically connected to an electrically conductive track 133 for connection to the brush carrier 135, which is made in the form of a separate component mounted under the base 117 of the cover plate. The tracks 133 in this example are of metal and are encapsulated within the base 117 of the cover plate. The tracks 133 stiffen the cover plate and are fixed on the latter by the in situ moulding technique used in the same way for the three tracks 127. The brush carrier is shown in Figure 6 and designated by the reference numeral 135. In a modified version, the tracks 133 are replaced by electrical conductors such as wires of circular, rectangular or oval cross section.
The brush carrier 135 is simplified as compared with those in the prior art, and includes a portion in the form of a support plate 137, which is L-shaped and carries at one end the housing 137 for the brushes, while the end of the other arm and the zone of the angle are adapted to enable the brush carrier to be fixed to the cover plate. It will be noticed that in Figure 6 there are two holes 141 for passage of fastening studs (not shown), which are coincident with passage holes 143 for the same studs, in the base 117 of the cover plate 100. These studs are anchored in the rear bearing like that of Figure 1, and at the same time they constitute fastening studs for securing the cover plate to the bearing plate. Application is achieved by screwing a nut on the free end of each stud. Figure 3 shows at 142 these nuts screwed on the studs.
Circular rebates (not given reference numerals) are of course provided in the holes 143. These rebates serve to accommodate the nuts 142, bearing on the bottoms of the rebates through a gripping washer. The bottom of the rebate and the hole 143 are, in one embodiment, delimited by a metallic washer which is secured by the in situ moulding technique to the cover plate. These washers avoid plastic flow of the material of the cover plate.
The L-shaped plate 137 is of electrically insulating material, and preferably of moulded plastics material, and it also carries two annular electrical contact pads 145, which are adapted to establish the electrical connections with the tracks 133 of the brush carrier connector 104. Contact is made with the aid of a stripped contact eye 148, which is arranged at the end of each strip 133, encapsulated in the base of the cover plate; each of the contacts 145 has a screw for a fastening nut which bears on the ear, with a tightening washer interposed. The contacts 145 are electrically connected to the brushes.
Given that the brush housing 139 of the brush carrier projects from the support plate 137, the base 117 of the cover plate 100 projects locally axially outwards in a zone 147, in which the housing 139 is situated when the brush carrier is fitted under the wall 117 of the cover plate. This projecting zone 147 is extended by ribs 149 towards the brush carrier connector 104. The ribs define an oblong air passage aperture.
The metallic tracks 133 are encapsulated within these ribs, and the wall of the cover plate in the zone 147, so that they have a sinuous form and stiffen the zone 147 and the ribs 149. This zone 147 also has rebates for receiving the nuts associated with the ears 148.
Referring to Figure 3, it is seen that the cover plate 100 is cut away, as described earlier herein, in a portion of its outer peripheral skirt portion 115, to enable the connector 106 to pass through and also to give radial access to the sensor carrier, where the rotary electrical machine is an
alternator-starter. The sensor carrier, which is of the type known per se, such as that which is for example shown at 257 in Figure 9 of the document WQ01/69762, is mounted below the base 117 of the cover plate, and is accordingly covered by the cover plate. The configuration and mounting of the sensor carrier are described in detail in that document. Fastening of the sensor carrier is obtained with the aid of two studs which are fixed with respect to the rear bearing plate 14, and of which only the two nuts 153 can be seen in Figure 3. These studs accordingly enable the sensor carriers to be fastened under the cover plate 100 and, at the same time, enable the latter to be fastened on the rear bearing plate. The passage holes for the studs are indicated at 155 in Figures 4 and 5, and are associated with rebates for receiving the nuts 153, in the same way as the rebates associated with the nuts 142, with a metallic washer being fixed with respect to the cover plate and delimiting the base of the rebate and the hole 155, so as to avoid plastic flow of the material of the cover plate.
In a modified version, the rotary electrical machine is an alternator, which renders the presence of a sensor carrier unnecessary; the opening 151 at the periphery of the cover plate 100 is not provided because there is no connector 106.
In that case, the cavity in the cover plate only contains the brush carrier. In another modified version, for reasons of standardisation, the opening 151 is retained.
In this type of machine, the rectifier for the alternating current produced by the wound stator that constitutes the armature of the alternator comprises, in the known way, at least one diode bridge. For more details, reference should be made for example to the document FR-A-2 297 513, which shows a rectifying device having two diode bridges, with delta connected or star connected connections of the armature windings of the stator, the phase outputs of which are adapted to be connected to the bridges. This device is then moved away from the alternator, which is of advantage where a plurality of bridges are provided; the rear bearing plate does not run the risk of being obstructed by the bridges.
It will be recalled that the rectifying device for the alternating current in an alternator-starter usually comprises at least one power transistor bridge, for example of the MOSFET type as described in the document FR-B-2 745 444, to which reference should be made for more deta8s.
The electronic command and control module accordingly comprises, in this case, a power module which includes the transistor bridge, and a control and interface module which controls the transistors of the power module. This control module, in particular, manages the following functions: -power
in the starting and alternator modes, regulation in the alternator mode, and transition from the starter mode to the alternator mode.
In all cases the outputs of the phases are connected to a phase connector which is adapted to be connected to an external electronic module, that is to say they are remote from the rotary electrical machine; the said electronic module comprises at least the rectifier device for the alternating current produced by the stator.
It should also be noted that, in order to cover the lugs 125 for fastening the phase outputs to the periphery of the cover plate, the cover plate includes a secondary cover element 157, which is an attached member and is in the form of an arc of a circle which is mounted on the appropriate zone of the periphery of the cover plate as can be seen in Figure 7. This cover element 157 is fastened on the cover plate 100 and is of electrically insulating material, preferably of moulded plastics. The secondary cover element 157 includes hollow bosses for housing the phase connection lugs 125 within them. The secondary cover element 157 is preferably snap-fitted on the cover plate 100. It has, for example, a central snap-fitting lug which is shouldered at its free end in order to engage with a shoulder on the cover plate 100.
It will be seen in Figures 4 and 5 that the skirt portion 115 has between two lugs 125 a notch, the base of which serves for abutment of the shouldered lug in the form of a hook. The circumferential edges of the secondary cover element 157 are each engaged in an axial air passage opening in the skirt portion 115, so that it is unable to turn. In a modified version, the cover element has an extension for covering the contacts 145 and the eyes 148.
It will be clear from the above description that the invention gives numerous advantages. Besides the external peripheral location of the connectors, and the fact that the connections are thus made radially from outside, it is of advantage that the cover plate accomplishes the functions of protection and support, which leads to simplification of the structure as compared with the state of the art. In addition, the brush carrier is made in the form of a separate component, as is the sensor carrier. These two components are mounted below the cover plate. The phase connector, by being placed at the periphery of the cover plate, reduces the size of the latter. The provision of the projecting element supported by the solid arms, with the latter extending from the cover plate and being fixed additionally by a fastening lug to the rear bearing plate, stiffens the arms even more, and renders them very robust.
Because of the in situ moulding technique, the cover plate is preferably made of thermoplastic material and is formed with bosses or other elements which are resistant to flow at the locations where gripping forces
are exerted, in particular for the fastening of the cover plate to the rear bearing plate, or in the region of the lug 121.
Material is economised in the region of the brush carrier 135. This material is different from that of the cover plate 100, and is more expensive than that of the cover plate 100, because it serves for guiding the brushes. The cost of the brush carrier 135 is reduced even more as the latter, firstly, has no connector, this being arranged more cheaply in the cover plate 100, and secondly, it has electrical connections which are shortened because of the presence of the conductor strips 133 integrated in the cover plate 100.
The secondary cover element 157 is preferably made of a material cheaper than that of the brush carrier and cover plate, because it does not guide the brushes, and nor does it serve for containing any electrical tracks.
The present invention is of course not limited to the embodiment described.
For example, the connecting flange of the arms 113 is, in a second embodiment of the invention, at right angles to the flange 112 of Figure 7, so that the threaded shank 208 extends radially, as does the phase connector 106. It is of course possible to set the shank 208 in a purely radial orientation.
In another version, the flange 112 is inclined, as is the phase connector.
The inclination of the flange is, in a further modified version, achieved by inclining the arms 113. In a modified version of this, the arms are bent. Thus it is easily possible to orientate the connector within the space available.
In a third embodiment of the invention, the assembly consisting of the flange 112 and arms 113, constituting the above mentioned projecting structure of the cover plate, is replaced by a solid boss which is formed integrally by moulding with the cover plate and which is secured directly on the rear bearing plate. The presence of the lug 121 is therefore not essential; the boss can be secured on the chimney element 209 and extend the projecting element 108 of the connector 106.
In another version, the boss is secured on the bearing plate with the aid of the stud associated with the nut 153, which is located in Figure 3 between the arms 113, so that the presence of a chimney element 209 is no longer obligatory, and the number of fastening points is reduced. To this end, the boss carries a thrust washer in the same way as that described in connection with the rebates associated with the holes 143 and 155. In this
case, the threaded portion 208 is part of a screw, the head of which bears on a washer of thermosetting material which is applied by the in situ moulding technique within the boss integral with the projecting element 108. In all cases, the projecting structure for support of the phase connector 102 has means for fastening on the rear bearing plate 14. The boss may be bent, and/or be inclined at the level of the projecting element 108.
In a fourth embodiment of the invention, the projecting element 108 of the connector 106 is part of the skirt portion 115 or base 117 of the cover plate, so that the connector 106 is oriented radially or axially. In a modified version of this, the projecting element 108 does not have a constant thickness, so that the connector 108 is inclined.
This fourth embodiment is appropriate in the case of an alternator which does not have a sensor carrier, because it is able to make use of the space available so that the lugs 125 can be implanted directly for fastening the phases directly at the level of the surfaces 109 to 111, within the cover plate 100, so that the tracks 127 are then no longer essential.
In a fifth embodiment of the invention, the cover plate is in two parts, namely a first part including the tracks 127, the arms 113 and the connector 106, together with a second part comprising the conductors 133, zone 147 and connector 104. In Figure 4, the line of separation of these two parts is indicated as a broken line. This enables one of the parts to be standardised, the other part being a part which can be adapted according to the application.
Thus the first part may be equipped with a phase connector according to the second, third and fourth embodiments of the invention. In a modified version, the connector 102 is orientated and/or implanted in some other way, for example axially.
The connector 104 is not necessarily part of the cover plate. In a modified version, it is part of the brush carrier 135, which in a further modified version also carries the voltage regulator.
The connector 104 is of course not necessarily arranged for radial access, but may be inclined and/or oriented axially, like the connector 102. All combinations are possible.
The connector 104 may take some other form and be of the female type, like the connectors 102 or 106.
According to the application, the connectors 104 and 102 are, in another modified version, further away from each other.
The tracks 127 or in another version the electri'cal conductors 127, in a further embodiment are arranged only on the skirt portion 115 or only on the base 117, and/or only the arms 113, or, in general terms, the projecting structure which is formed integrally by moulding with the projecting element 108. The tracks 127 are encapsulated at least partly within this projecting portion in all cases. The same is true for the tracks or electrical conductors 133, which may only be arranged on the skirt portion 115 and/or the connector 104.
Instead of using studs for fastening the cover plate to the rear bearing plate 14, it is of course possible to make use of screws, the heads of which bear on the cover plate, and which are preferably reinforced at this point by a washer which is resistant to plastic flow, and the threaded portion is screwed into a boss projecting from the rear bearing plate. In a modified version, fastening of the cover plate to the rear bearing plate is achieved by riveting, adhesive bonding or any other means of fastening.
As described above, the electronic module may be constructed so that it does not include the voltage regulator. It is remote from the rotary electrical machine.
In modified versions, the phase connector is of the type described in the document DE-A-100 41 986 (FR-A-2 799 053), the projecting portion extending from the cover plate being then able to have the same form as that shown in Figure 2 of the said document.




WE CLAIM:
1. A protective cover plate (100) of electrically insulating material, adapted to be mounted on the rear bearing plate (14) of a polyphase rotary electrical machine of the type comprising, an external carcass (13, 14) having said rear bearing plate (14) and carrying a wound polyphase stator (8), the phase outputs of which are connected to a phase connector (102) which is adapted to be connected to an external electronic module, and a support structure in an electrically insulated material, which is fixed on the rear bearing plate (14) and which carries the phase connector (102), characterised in that the cover plate (100) is so configured as to accomplish, at the same time, the functions of supporting the phase connector (102) and of covering the rear bearing plate (14).
2. A cover plate as claimed in claim 1, wherein the phase connector (102) of the stator is supported by a projecting structure (113, 112) projecting from the cover plate (100).
3. A cover plate as claimed in claim 2, wherein the projecting structure (113, 112) has means (112, 121) for fastening to the rear bearing plate (14).
4. A cover plate as claimed in claim 3, wherein the projecting structure is disposed at the outer periphery of the cover plate (100).
5. A cover plate as claimed in claim 4, wherein the phase connector (102) is located, by virtue of the projecting structure (113, 112), at a location beyond the outer periphery of the cover plate (100).
6. A cover plate as claimed in claim 3, wherein the projecting structure (113, 112) has arms (113) projecting from the cover plate (100).
7. A cover plate as claimed in claim 6, wherein the cover plate (100) has a peripheral external skirt portion (115) and a base (117), and in that the support arms (113) are fixed with respect to the base (117) and skirt portion (115) of the cover plate (100).
8. A cover plate as claimed in claim 6, wherein the two arms (113) are joined together by a flange (112) which carries the phase connector (102).
9. A cover plate as claimed in claim 8, wherein the phase connector (102) has a shank (208) extending through the flange (112), and in that the shank is fixed with respect to a support lug (121) which is adapted to be fixed to the rear bearing plate (14).
10. A cover plate as claimed in claim 9, wherein the support lug (121) bears on a chimney element (209) fixed with respect to the rear bearing plate, and is formed with a through passage hole for a member fastening it to the chimney element (209).
11. A cover plate as claimed in claim 10, wherein the phase connector (102) has an internally hollow projecting element (108) carried by the flange (112), in that the shank (208) extends through the flange (112) and projecting element (108), in that the support lug (121) has a projecting portion at the level of the zone at which it is joined to the shank (208), and in that the projecting structure is mounted within the projecting element (108).
12. A cover plate as claimed in claim 11, wherein the projecting structure bears on a member which is formed with a through passage hole for the shank (208), and in that the member having this hole is of thermosetting plastics material resistant to plastic flow and attached by in situ moulding to the interior of the projecting element (108).
13. A cover plate as claimed in claim 1, wherein the shank (208) is threaded.
14. A cover plate as claimed in claim 8, wherein the phase connector (102) is connected to input connections (125) of the phases, for fastening of the outputs of the phases, by electrical conductors (127) which are encapsulated at least partly within the projecting structure (113, 112).
15. A cover plate as claimed in claim 14, wherein the electrical conductors consist of electrical tracks (127), and in that each of at least two electrical tracks (127) is connected to an electrical contact surface (109 to 111) of the phase connector (102).
16. A cover plate as claimed in claim 15, wherein the electrical tracks (127) are encapsulated in the cover plate (100) and in the arms (113), and in that the electrical tracks (127) are so configured as to be encapsulated in the support flange (112).
17. A cover plate as claimed in claim 2, wherein the phase connector (102) is connected to input connections (125) of the phases, for fastening the outputs of the phases, by electrical conductors (127) encapsulated at least partly in the projecting structure (113, 112), and in that the input connections (125) of the phases are disposed at the outer periphery of the cover plate (100) and are overlaid by a secondary cover element (157) of electrically insulating material, which is fastened on the cover plate (100).
18. A cover plate as claimed in claim 17, wherein the secondary cover element (157) is in the form of an arc of a circle, in that the input connections of the phases consist of fastening lugs (125), and in that the secondary cover element (157) has hollow bosses for housing the fastening lugs (125).
19. A cover plate as claimed in claim 2, wherein a brush carrier (135) is overlaid by the cover plate (100) and is associated with a connector (104), and in that the connector (104) of the brush carrier (135) is made in one piece with the cover plate (100).
20. A cover plate as claimed in claim 19, wherein the cover plate (100) has a base (117), and in that the connector (104) for the brush
carrier (135) is connected to the brush carrier (135) through electrically conductive tracks encapsulated in the base (117) of the cover plate (100).
21. A cover plate as claimed in claim 20, for an alternator-starter which has a sensor carrier and a connector (106) for the sensor carrier, wherein the sensor carrier is mounted under the base (117) of the cover plate (100), and in that the sensor carrier connector (104) passes radially through an opening (151) in the peripheral annular wall of the cover plate.
22 A cover plate as claimed in claim 19, wherein it is in two parts, and in that one of the parts comprises the phase connector, while the second part covers the brush carrier (135).
23. An alternator, wherein it has a cover plate (100) as claimed in claim 1.

Documents:

1382-delnp-2005-abstract.pdf

1382-delnp-2005-claims(cancelled).pdf

1382-DELNP-2005-Claims.pdf

1382-delnp-2005-complete specification (as files).pdf

1382-delnp-2005-complete specification (granted).pdf

1382-delnp-2005-correspondence-others.pdf

1382-delnp-2005-correspondence-po.pdf

1382-DELNP-2005-Description (Complete).pdf

1382-delnp-2005-drawings.pdf

1382-delnp-2005-form-1.pdf

1382-delnp-2005-form-18.pdf

1382-DELNP-2005-Form-2.pdf

1382-DELNP-2005-Form-3.pdf

1382-delnp-2005-form-5.pdf

1382-delnp-2005-gpa.pdf

1382-delnp-2005-petition-137.pdf

1382-delnp-2005-petition-138.pdf

abstract.jpg


Patent Number 249589
Indian Patent Application Number 1382/DELNP/2005
PG Journal Number 44/2011
Publication Date 04-Nov-2011
Grant Date 27-Oct-2011
Date of Filing 05-Apr-2005
Name of Patentee VALEO EQUIPMENTS ELECTRIQUES MOTEUR
Applicant Address 2 RUE ANDRE-BOULLE, F-94017 CRETEIL CEDEX, FRANCE
Inventors:
# Inventor's Name Inventor's Address
1 BENOIT REGNARD 90 BOULEVARD JEAN-JAURES, F-93190 LIVRY-GARGAN, FRANCE
2 ROGER ABADIA 39 AVENUE DU NORD, F-93360 NEUILLY-PLAISANCE, FRANCE
3 PHILIPPE LEFRANCOIS 3 PLACE DE LA LEVRIERE, F-94000 CRETEIL,FRANCE
PCT International Classification Number H02K 5/22
PCT International Application Number PCT/FR2003/003168
PCT International Filing date 2003-10-24
PCT Conventions:
# PCT Application Number Date of Convention Priority Country
1 02/13379 2002-10-25 France