FR3089717A1 - Rotating electric machine rotor comprising a fan - Google Patents

Abstract

The present invention relates essentially to a rotor (1) of a rotary electrical machine comprising: a rotor shaft (2); a rear pole wheel (32); a fan (4) mounted on the rear pole wheel (32); a manifold (5) mounted on the rotor shaft (2); a coil comprising a conductive wire electrically wound around a coil body (6), the conductive wire comprising two ends electrically connected to the collector (5); at least one tab (7) comprising means for guiding at least one of the ends of the conductive wire towards the collector (5); the fan (4) comprising at least one notch (43) configured to receive the tab (7) of the rotor (1) so as to block the fan (4) in rotation. Figure for the abstract: Figure 1A

Description

Description

Title of the invention: Rotor of a rotating electrical machine comprising a fan

Technical area

The technical field of the invention is that of rotating electrical machines, such as alternators or alternator-starters or reversible machines of motor vehicles with thermal engine. The present invention relates more particularly to a rotating electrical machine rotor comprising a fan locked in rotation and a rotating electrical machine comprising such a rotor.

TECHNOLOGICAL BACKGROUND OF THE INVENTION

A motor vehicle with an internal combustion engine is equipped with a rotating electric machine which, in alternator mode, has the function of transforming the mechanical energy coming from the engine into electrical energy with the aim in particular of recharging the vehicle battery and supplying power the vehicle's on-board network. To do this, the rotary electric machine comprises a rotor mounted on a shaft driven in rotation by the motor and a stator surrounding the rotor, the stator being carried by a casing comprising two bearings.

The rotating electric machine has elements, such as a control circuit, a rectifying bridge and windings of the rotor and the stator, which generate heat when the machine is in operation. It is therefore necessary to cool the rotating electric machine. To do this, the rotor includes at least one fan. Some machines have a single fan, preferably located at the back of the rotor. Other machines have two fans on the front and rear of the rotor, respectively. Currently, whether at the front or at the rear of the rotor, the fan is rotatably mounted on a pole wheel of the rotor during a welding step.

Welding the fan on a pole wheel of the rotor requires high electrical power, which has several drawbacks. In particular, the maximum electrical power authorized by the contract signed with an electricity supplier is generally not sufficient to carry out the welding step in parallel on several production lines, which limits the production rate. To be able to carry out several welding steps simultaneously, it would then be necessary to subscribe to a contract authorizing greater electrical power, but the cost of such a contract would obviously be much higher, which would ultimately increase the cost of production.

In addition, to verify the reliability of the welds, destructive tests are carried out. Such tests have a high cost in addition to requiring time to be carried out. Consequently, it appears that welding the fan to the rotor does not make it possible to reconcile both a high production speed and a reduced production cost. Summary of the invention

The present invention aims to solve the problems which have just been mentioned by proposing, according to a first aspect of the invention, a rotor of a rotary electric machine comprising:

- a rotor shaft extending along a longitudinal axis;

- A first polar wheel called "front polar wheel" and a second polar wheel called "rear polar wheel", the two polar wheels being arranged transversely to the longitudinal axis;

- A fan mounted on the rear pole wheel, the fan comprising a first main surface called "front face" arranged opposite the rear pole wheel and a second main surface called "rear face" opposite the first main surface;

- A collector mounted on the rotor shaft, the collector comprising a base extending in a plane substantially orthogonal to the longitudinal axis, the base of the collector being disposed opposite the rear face of the fan;

- A coil disposed between the two pole wheels, the coil comprising a coil body and a conductive wire electrically wound around the coil body, the conductive wire comprising two ends electrically connected to the collector;

- At least one tab comprising a means for guiding at least one of the ends of the conductive wire towards the collector, the tab comprising a first portion extending axially towards the rear of the rotor and a second portion extending the first portion;

- At least one notch in the fan, the notch being configured to receive the first portion of the rotor leg so as to block the fan in rotation, the second portion of the rotor leg being folded over the rear face of the fan so as to keep the fan axially on the rear pole wheel.

Thanks to the invention, it is possible to fix the fan on the rear pole wheel without having to resort to a welding step. This reduces the time and cost of producing the rotor.

According to one embodiment, the notch is formed at the periphery of the fan. For example, the notch extends from the outer periphery of the fan.

According to one embodiment, the tab extends from the coil body.

According to one embodiment, the rotor comprises at least one rod extending axially towards the rear of the rotor, the rod cooperating with an eccentric opening formed through the fan to ensure the correct angular positioning of the fan on the pole wheel back.

According to one embodiment, the rod extends from the coil body.

According to one embodiment, the rod comprises a body having a first diameter and a head having a second diameter greater than the first diameter, the eccentric opening comprising:

- An insertion zone having a first width greater than the second diameter, the rod being initially inserted through the insertion zone so that the head of the rod protrudes entirely from the eccentric opening; and

- A stop zone having a second width between the first diameter and the second diameter, the rod being in abutment against the stop zone when the fan is correctly positioned so that the head of the rod maintains the fan axially.

According to one embodiment, the rotor has several tabs associated respectively with several notches and several rods respectively associated with several eccentric openings, the notches and the eccentric openings of the fan are respectively arranged diametrically opposite, the notches being aligned in a first direction and the eccentric openings being aligned in a second direction substantially orthogonal to the first direction.

According to one embodiment, the rear face of the fan comprises at least one lug cooperating with a housing formed in the base of the manifold to ensure the correct angular positioning of the fan on the rear pole wheel.

According to one embodiment, the rotor has several legs respectively associated with several notches and several lugs associated respectively with several housings, the notches and the lugs of the fan are respectively arranged in diametrically opposite manner, the notches being aligned in a first direction and the pins being aligned in a second direction substantially orthogonal to the first direction.

According to one embodiment, the fan has a central opening for the passage of the rotor shaft, the central opening of the fan and the base of the manifold having complementary shapes.

According to one embodiment, the rear pole wheel has an external transverse face disposed opposite the front face of the fan, a recess being formed in the external transverse face of the rear polar wheel, the front face of the fan comprising a portion projecting having a shape complementary to that of the recess so that the recess and the projecting portion cooperate to ensure the centering of the fan on the rear pole wheel.

According to one embodiment, the rotor is impregnated with an electrically insulating substance, grooves being formed in the front face of the fan to facilitate the flow of the insulating substance.

A second aspect of the invention relates to a rotary electrical machine comprising a rotor according to the first aspect of the invention.

Brief description of the drawings

The invention and its various applications will be better understood on reading the description which follows and on examining the accompanying figures, among which:

[Fig.lA] and [Figure IB] are respectively a perspective view and a longitudinal sectional view of a rotor, according to an embodiment of the invention;

[Fig.2] is a perspective view of a coil body of the rotor of [Figure 1];

[Fig.3A], [Figure 3B] and [Figure 3C] are respectively a perspective view, a side view and a bottom view of a rotor fan of [Figure 1];

[Fig.4A], [Figure 4B] and [Figure 4C] are enlarged views of the rotor of [Figure 1] centered around legs of the coil and representing different phases of the rotor assembly by rotation;

[Fig.5] is an enlarged view of an opening in the fan of [Figure 3A], [Figure 3B] and [Figure 3C] to accommodate and then block by rotation a rod coil;

[Fig.6A] and [Figure 6B] are other enlarged views of the rotor of [Figure 1] centered around the coil rods and representing different phases of the rotor assembly by rotation;

[Fig.7A] and [Figure 7B] are respectively a perspective view and a bottom view of a collector of the rotor of [Figure 1];

[Fig.8] is a perspective view of a rear pole wheel of the rotor of [Figure 1] ·

The figures are presented only for information and in no way limit the invention.

For clarity, identical or similar elements are identified by identical reference signs in all the figures.

DETAILED DESCRIPTION OF AT LEAST ONE EMBODIMENT

A motor vehicle with a thermal engine is equipped with a rotating electric machine, such as an alternator or an alternator-starter or a reversible machine, configured to transform the mechanical energy coming from the thermal engine into electric energy for the purpose including recharging the vehicle battery and supplying power to the vehicle's on-board network.

An alternator-starter or a reversible machine is a particular alternator which is reversible, that is to say it also has an operating mode in which it transforms electrical energy into mechanical energy, in particular to start the engine of the motor vehicle. In this case, the rotating machine behaves like an electric motor.

The rotary electrical machine comprises a stator and a rotor configured to be driven in rotation inside the stator. The rotor and the stator are arranged inside a casing comprising two parts usually called "bearings".

[Fig.lA] and [Figure IB] respectively show a perspective view, a top view and a longitudinal sectional view of a rotor 1 for a rotary electric machine, according to one embodiment of the invention. In [Figure IA], the rotor 1 is shown in a direction from the rear of the rotor 1 towards the front of the rotor 1 so that a front face 11 of the rotor 1 is hidden and a rear face 12 of rotor 1 is visible.

The rotor 1 comprises a rotor shaft 2 extending along a longitudinal axis X which corresponds to the axis of rotation of the rotor 1. The rotor 1 also includes a front pole wheel 31 and a rear pole wheel 32 arranged transversely relative to the longitudinal axis X, a fan 4 mounted on the rear pole wheel 32, a manifold 5 mounted on the shaft 2 and a coil (not visible in [fig.lA] and [Figure IB]) arranged between the two pole wheels 31, 32.

Throughout the description and in the claims, the terms "axial", "radial" and "transverse", as well as the adverbs derived from these terms, are defined with respect to the longitudinal axis X.

Throughout the description and in the claims, the terms "front" and "rear" are defined with respect to the direction of the longitudinal axis X, the rear of the rotor 1 corresponding to the part of the 'shaft 2 on which the manifold 5 is mounted.

Out of all the examples shown, a top view, respectively from below, of the rotor 1 or of a part mounted on the rotor 1 is a view considered in the longitudinal direction X and in the direction from rear, respectively from the front, of the rotor 1 towards the front, respectively the rear, of the rotor 1.

In this embodiment, the pole wheels 31, 32 have claws 33 arranged on the periphery of the pole wheels 31, 32. The claws 33 extend axially from their respective pole wheel 31, 32 in the direction of the pole wheel 32, 31 opposite. The pole wheels 31, 32 then form a cage in which the coil is arranged.

The coil has a coil body 6 and a conductive wire electrically wound around the coil body 6. The conductive wire has two ends electrically connected to the collector so as to supply electrical energy to the rotor coil 1 when the electric machine is in operation.

The rotor 1 here comprises two legs 7 each comprising means for guiding one of the ends of the conductive wire to the collector 5. The guide means are for example walls extending from the legs. The legs 7 each have a first portion 71 extending axially towards the rear of the rotor and a second portion 72 extending the first portion 71. The guide means are in particular arranged on the second portion 72.

[Fig.2] shows a perspective view of the coil body 6 which has a front transverse flange 61 and a rear transverse flange 62 spaced from one another. The coil body 6 also includes a winding portion 63 which extends axially from a flange 61, 62 in the direction of the opposite flange 62, 61. In this embodiment, the tabs 7 are arranged on the rear flange 62 of the coil body 6 and are made from material with the flange.

[Fig.3A], [Figure 3B] and [Figure 3C] show the fan 4 respectively in perspective view, in profile view and in view from below. The fan 4 comprises a first main surface 41 called “front face” arranged opposite the rear pole wheel 32 and a second main surface 42 called “rear face” opposite to the first main surface 4L The fan 4 has for example the general shape of a disc. Advantageously, the fan 4 also includes fins 44 arranged on the rear face 42 and on the periphery of the fan 4 so as to improve the cooling efficiency.

The fan 4 is provided with two notches 43 formed at its periphery. Each tab 7 cooperates with one of the notches 43 so as to block the fan 4 in rotation relative to the pole wheel 32.

The notches 43 are for example arranged diametrically opposite. Each notch 43 is configured to receive the first portion 71 of one of the legs 7 of the rotor 1 so as to block the fan 4 in rotation relative to the pole wheel 32. In addition, the second portion 72 of each leg 7 of the rotor 1 is folded over the rear face 42 of the fan 4 so as to axially hold the fan 4 on the rear pole wheel 32 when the rotary electric machine is in operation.

[Fig.4A], [Figure 4B] and [Figure 4C], which show enlargements of the rotor 1 framed around the legs 7, illustrate the progress of the assembly of the fan 4 on the rear pole wheel 32. The first portion 71 of each leg 7 abuts against one end of one of the notches 43 then the second portion 72 of each leg 7 is folded down on the rear face 42 of the fan 4. The cooperation of the legs 7 and the notches 43 allows the fan 4 to be fixed on the rear pole wheel 32 without having to resort to a welding step, unlike what is done in the prior art. Consequently, the present invention makes it possible both to reduce the assembly time of the rotor 1 and its production cost.

The rotor 1 may also include two rods 8 extending axially towards the rear of the rotor 1, each rod 8 cooperating with an eccentric opening 48 formed through the fan 4 to ensure the correct angular positioning of the fan 4 on the rear polar wheel 32. The rods 8 make it easier to assemble the fan 4 on the rear polar wheel 32. Preferably, the rods 8 are arranged on the rear flange 62 of the coil body 6, as illustrated in [ fig.2].

The rods 8 have for example a generally cylindrical shape. The rods each comprise a body 81 having a first diameter and a head 82 having a second diameter greater than the first diameter.

[Fig.5] shows an enlargement of one of the openings 48 of the fan 4. In addition to the rods 8, the eccentric openings 48 each have an insertion area 48a having a first width greater than the second diameter and a stop zone 48b having a second width between the first diameter and the second diameter.

[Fig.6A] and [Ligure 6B] show enlargements of the rotor 1 framed around the rods 8 and which correspond to different times of the assembly of the fan 4 on the rear pole wheel 32. The rods 8 are initially inserted through their respective insertion zone 48a so that the head 82 of the rods 8 entirely protrudes from the eccentric openings 48. Then, the fan is rotated until the rods 8 come to bear against their stop zone 48b respective. The fan 4 is thus correctly positioned, and the head 82 of the rods 8 then contributes to keeping the fan 4 axially on the rear pole wheel 32 when the rotor 1 is in rotation.

The openings 48 of the fan 4 are for example arranged diametrically opposite. Advantageously, the notches 43 are aligned in a first direction and the openings 48 are aligned in a second direction substantially orthogonal to the first direction. This configuration improves the retention of the fan 4 on the rear pole wheel 32 in order to prevent the fan 4 from lifting when the rotor 1 is rotating.

Throughout the description and in the claims, the term "substantially orthogonal" means an angle between 80 ° and 100 °.

[Fig.7A] and [Ligure 7B] show the manifold 5 respectively in perspective view and in bottom view. The manifold 5 has a base 51 extending in a plane substantially orthogonal to the longitudinal axis X. The base 51 of the manifold 5 is arranged opposite the rear face 42 of the fan 4. Two housings 59 are for example formed in the base 51 of manifold 5.

The fan 4 may also include two lugs 49 arranged on the rear face 42 of the fan 4, as illustrated in [fig.3A]. Each lug 49 cooperates with one of the housings 59 of the manifold 5 to ensure the correct angular positioning of the fan 4 on the rear pole wheel 32. The lugs 49 act as stops against which the bottom of the housings 49 comes to bear.

The lugs 49 of the fan 4 are for example arranged diametrically opposite. Preferably, the pins 49 are aligned in the same direction as the rods 8, that is to say substantially orthogonal to the direction of alignment of the notches 43 of the fan 4.

Advantageously, the base 51 of the manifold 5 has an elongated shape so as to improve the retention of the fan 4 on the rear pole wheel 32 in order to prevent the fan 4 from being raised when the rotor 1 is in rotation. Indeed, the base 51 of the collector contributes to press the fan 4 on the rear pole wheel 32 at the lugs 49. The base 51 of the collector has for example the general shape of a rhombus.

The fan 4 further comprises a central opening 46 for the passage of the rotor shaft 2. Advantageously, the central opening 46 of the fan 4 and the base 51 of the manifold 5 have complementary shapes. Thus, the fan 4 can be installed before or after the collector, which allows more flexibility during assembly of the rotor 1. In this case, the base 51 of the collector 5 extends in a direction offset angularly by relative to the direction in which the central opening extends 46.

A perspective view of the rear pole wheel 32 is illustrated in [fig.8]. The rear pole wheel 32 has an external transverse face 32a disposed opposite the front face 41 of the fan 4. A recess 32b of circular shape is for example formed in the external transverse face 32a of the rear pole wheel 32. The front face 41 of the fan 4 may include a projecting portion 41b, as illustrated in [Ligure 3B], having a shape complementary to that of the recess 32b so that the recess 32b and the projecting portion 41b advantageously cooperate to ensure centering the fan 4 on the rear pole wheel 32.

Once assembled, the rotor 1 is impregnated with an electrically insulating substance such as a varnish. To do this, the rotor 1 is immersed in a bath containing the insulating substance. Advantageously, grooves 41c are formed in the front face 41 of the fan 4 so as to facilitate the flow of the insulating substance. In addition, when the insulating substance present in the grooves 41c hardens, this makes it possible to carry out chemical bonding and therefore to improve the retention of the fan 4 on the rear pole wheel 32.

Naturally, the invention is not limited to the embodiments described with reference to the figures and variants could be envisaged without departing from the scope of the invention.

Claims (1)

Rotor (1) of a rotary electrical machine comprising: at. a rotor shaft (2) extending along a longitudinal axis (X); b. a first polar wheel (31) called "front polar wheel" and a second polar wheel (32) called "rear polar wheel", the two polar wheels (31, 32) being arranged transversely to the longitudinal axis (X) ; vs. a fan (4) mounted on the rear pole wheel (32), the fan (4) comprising a first main surface (41) called "front face" arranged opposite the rear pole wheel (32) and a second main surface ( 42) called "rear face" opposite the first main surface (41); d. a manifold (5) mounted on the rotor shaft (2), the manifold (5) comprising a base (51) extending in a plane substantially orthogonal to the longitudinal axis (X), the base (51) of the collector (5) being arranged opposite the rear face (42) of the fan (4); e. a coil disposed between the two pole wheels (31, 32), the coil comprising a coil body (6) and a conductive wire electrically wound around the coil body (6), the conductive wire comprising two ends electrically connected to the collector ( 5); f. at least one tab (7) comprising a means for guiding at least one of the ends of the conductive wire towards the collector (5), the tab (7) comprising a first portion (71) extending axially towards the rear of the rotor (1) and a second portion (72) extending the first portion (71); the rotor (1) being characterized in that at least one notch (43) is formed in the fan (4), the notch (43) being configured to receive the first portion (71) of the tab (7) of the rotor (1) so as to block the fan (4) in rotation, the second portion (72) of the tab (7) of the rotor (1) being folded over the rear face (42) of the fan (4) so as to axially hold the fan (4) on the rear pole wheel (32). Rotor (1) according to claim 1, characterized in that it comprises at at least one rod (8) extending axially towards the rear of the rotor (1), the rod (8) cooperating with an eccentric opening (48) formed through the fan (4) to ensure the correct angular positioning of the fan ( 4) on the rear pole wheel (32). [Claim 3] Rotor (1) according to claim 2, characterized in that the rod (8) comprises a body (81) having a first diameter and a head (82) having a second diameter greater than the first diameter, the eccentric opening (48) comprising: at. an insertion zone (48a) having a first width greater than the second diameter, the rod (8) being initially inserted through the insertion zone (48a) so that the head (82) of the rod (8) protrudes entirely from the eccentric opening (48); and b. a stop zone (48b) having a second width between the first diameter and the second diameter, the rod (8) being in abutment against the stop zone (48b) when the fan (4) is correctly positioned so that the head (82) of the rod (8) axially maintains the fan (4). [Claim 4] Rotor (1) according to any one of claims 2 and 3, characterized in that it comprises several lugs (7) respectively associated with several notches (43) and several rods (8) respectively associated with several eccentric openings (48) , the notches (43) and the eccentric openings (48) of the fan (4) being respectively arranged diametrically opposite, the notches (43) being aligned in a first direction and the eccentric openings (48) being aligned in a second direction substantially orthogonal to the first direction. [Claim 5] Rotor (1) according to any one of claims 1 to 4, characterized in that the rear face (42) of the fan (4) comprises at least one lug (49) cooperating with a housing (59) formed in the base ( 51) of the manifold (5) to ensure the correct angular positioning of the fan (4) on the rear pole wheel (32). [Claim 6] Rotor (1) according to claim 5, characterized in that it comprises several lugs (7) associated respectively with several notches (43) and several lugs (49) respectively associated with several housings (59), the notches (43) and the lugs (49) of the fan (4) are respected tively arranged in diametrically opposite manner, the notches (43) being aligned in a first direction and the lugs (49) being aligned in a second direction substantially orthogonal to the first direction. [Claim 7] Rotor (1) according to any one of claims 1 to 6, characterized in that the fan (4) has a central opening (46) for the passage of the rotor shaft (2), the central opening (46 ) of the fan (4) and the base (51) of the manifold (5) having complementary shapes. [Claim 8] Rotor (1) according to any one of claims 1 to 7, characterized in that the rear pole wheel (32) has an external transverse face (32a) disposed opposite the front face (41) of the fan (4), a recess (32b) being formed in the external transverse face (32a) of the rear pole wheel (32), the front face (41) of the fan (4) comprising a projecting portion (41b) having a shape complementary to that of the recess (32b) so that the recess (32b) and the projecting portion (41b) cooperate to ensure the centering of the fan (4) on the rear pole wheel (32). [Claim 9] Rotor (1) according to any one of claims 1 to 8, characterized in that it is impregnated with an electrically insulating substance, grooves (41c) being formed in the front face (41) of the fan (4) for facilitate the flow of the insulating substance. [Claim 10] Rotating electric machine characterized in that it comprises a rotor (1) according to any one of claims 1 to 9. 1/6