JP6900361B2 - Electric rotating machine for optimum cooling - Google Patents

Description

The present invention relates to an electric rotating machine for optimum cooling. In particular, the present invention is advantageously applied to, but not limited to, high power reversible electromechanical machines designed to operate in alternator and engine modes.

As is generally known, an electric rotating machine includes a stator and a rotor integrated with a shaft. The rotor can be integral with the drive and / or driven shaft and can belong to an alternator, an electric engine, or an electric rotating machine in the form of a reversible machine that can operate in either mode.

The stator is mounted on a housing configured to rotate the shaft, for example through the mediation of a spool. The rotor comprises a body consisting of a plurality of metal sheets held together, which are in the shape of a package by a suitable fixing system such as a rivet that axially penetrates the body of the rotor. As described in Document EP0803962, the rotor comprises, for example, a pole in the form of a permanent magnet placed in a cavity located within the magnetic body of the rotor. Alternatively, in a so-called "protruding" pole structure, the pole consists of a coil wound around a rotor arm.

On the other hand, the stator comprises a body composed of a plurality of thin sheet metal pieces forming a crown, the inside of which is provided with a notch open inward to receive the phase windings. These spools form protrusions that cross the notch of the stator body and project from both sides of the stator body. Phase windings are obtained from enamelled continuous wires or from conductor elements in the form of pins joined together by welding. These spools are multi-phase windings connected in a star or triangle, the outlet of which is coupled to a voltage rectifying bridge.

In the construction of hybrid motor vehicles, high power reversible electric rotating machines can be incorporated into various elements of the drive chain. Therefore, the machine may be connected to the vehicle's transmission, clutch or differential. Thus, the electromechanical machine operates in alternator mode to supply energy to the vehicle battery and in-flight power supply, and in engine mode, which is involved not only in starting the engine but also in driving the vehicle, either alone or in combination with the engine. It will be suitable for doing.

Considering the large power of 18 kW to 50 kW, the electric machine is likely to overheat during operation. It is an object of the present invention to optimize the cooling of this type of machine.

To this end, the present invention
-1 housing and
-1 stator and
-Multiple channels extending between the stator and the housing for the passage of coolant,
In an electric rotating machine equipped with
The housing has multiple openings and
Each of the openings opens to the outside of the electrorotating machine at one end and from the side of the channel at the other end.
We propose an electric rotating machine, which is characterized by this.

Therefore, in the present invention, for example, a distribution chamber for a coolant such as oil is prepared outside the machine, and the liquid is supplied to the internal channel through an opening so as to be uniformly dispersed inside the machine. It makes it possible to improve the cooling of electric rotating machines.

According to one embodiment, the plurality of openings are arranged at an angle according to the peripheral edge of the housing.

According to one embodiment, the housing comprises recesses, particularly peripheral recesses, that form at least a portion of the coolant distribution chamber when the electrorotating machine is inserted into a host element.

According to one embodiment, the cross sections of the different openings vary depending on the angular position of the openings so that the coolant can flow through each channel at approximately the same pressure.

According to one embodiment, the opening exhibits a crescent-shaped cross section over an angle portion of at least 100 degrees, especially 180 degrees.

According to one embodiment, the housing comprises a groove intended to receive the seal, especially in its outer wall.

According to one embodiment, the groove is designed to receive an O-ring.

According to one embodiment, the housing comprises an axial guide element when it is inserted into an envelope of a host element intended to be mechanically coupled to the electrorotating machine, and the host. It comprises a centering element of the electric rotating machine with respect to the envelope of the element.

According to one embodiment, the electric rotating machine comprises a shaft, wherein the shaft.
-A mechanism for binding to the host element at its first end,
-A coordinator at its second end, which allows the electric rotating machine to cause rotation of the shaft when inserted into the envelope of the host element.
Have.

According to one embodiment, the output of the machine can be 10 kW to 50 kW.

According to one embodiment, the outer diameter of the rotor is 8 to 14 cm, particularly 10 to 12 cm, preferably 11 cm.

According to one embodiment, the outer diameter of the stator is 10 to 20 cm, particularly 13 to 18 cm, preferably 15 cm.

According to one embodiment, the cooling circuit is designed to allow the coolant to flow into the axial perforations made in the shaft.

Similarly, an object of the present invention is to provide a unit comprising an envelope of host elements and the above-mentioned electric rotating machine inserted into the envelope.

According to one embodiment, the distribution chamber is defined by a portion of the inner wall of the envelope and a portion of the outer wall of the housing.

According to one embodiment, the unit is provided with a seal , especially an O-ring , to ensure the closure of the distribution chamber. In this way, it is forced to flow into the machine through the peripheral opening formed in the oil housing.

According to one embodiment, the seal is placed in the groove.

According to one embodiment, the housing comprises a flat support surface for the corresponding flat surface of the envelope of the host element to ensure that the distribution chamber is watertight. Thus, the chamber is defined by the portion of the inner wall of the envelope, by the portion of the outer wall of the housing, by the flat contact zone between the seal and the envelope of the housing.

According to one embodiment, the openings each exhibit an axis extending along the axis of rotation of the electric rotating machine.

According to one embodiment, the oil injection direction is inclined with respect to the axis of the opening.

According to one embodiment, the liquid placed in the distribution chamber is under pressure and flows at an output of 3 to 11 liters per minute.

The present invention will be better understood by reading the following description and scrutinizing the drawings that accompany it. These drawings are for illustration purposes only and do not limit the present invention at all.

Longitudinal sectional view of the electric rotating machine according to the present invention. Longitudinal sectional view of an electric rotating machine according to the present invention, excluding moving parts installed inside a host element. A perspective view of an electric rotating machine according to the present invention according to an angle. A perspective view of an electric rotating machine according to the present invention according to another angle. Front view of the electric rotating machine according to the present invention. A partial cross-sectional view of an electric rotating machine according to the present invention. FIG. 3 is a perspective view of a rear bearing of an electric rotating machine according to the present invention. A longitudinal sectional view showing a flow direction of a coolant inside an electric rotating machine according to the present invention. FIG. 3 is a perspective sectional view showing a flow direction of a coolant inside an electric rotating machine according to the present invention.

The same, similar or similar elements are labeled with the same reference numerals throughout the drawing. In the following description, it is understood that the "front" element is located alongside the host element on the side of the mechanical coupling mechanism such as a pinion or pulley, and the "rear" element is located on the opposite side.

FIG. 1 shows an electric rotating machine 10 provided with a multi-phase stator 11 surrounding an X-axis rotor 12 mounted on a shaft 13. The stator 11 is supported by a housing 16 configured to rotate the shaft 13. The stator 11 surrounds the rotor 12 so that there is an air gap between the inner edge of the stator 11 and the outer edge of the rotor 12.

The electromechanical machine 10 is intended to be installed inside the envelope 21 of the host element 20 belonging to the drive chain of the automatic vehicle shown in FIG. For example, the host element 20 intended to be mechanically coupled to the electromechanical machine 10 may take the form of, for example, a clutch, transmission or differential. For this purpose, the shaft 13 supports a connecting mechanism 24, such as a pinion, at one of its ends, which engages the corresponding pinion (not shown) of the host element 20. It is intended to ensure torque transmission between the two elements. The pinion 24 can be an offset pinion mounted on the shaft 13 or another type of pinion. As a modification, the coupling mechanism 24 may consist of a pulley intended to work with the belt.

The machine 10 operates in alternator mode to supply energy to the vehicle battery and power source in the vehicle, and in engine mode which is involved not only in starting the engine but also in driving the vehicle, either alone or in combination with the engine. Suitable for.

More precisely, the rotor 12 includes a body 25 formed of a plurality of metal sheets. These metal sheets are held together and are in the shape of a sheet package by a suitable fixing system 26 such as rivets that axially penetrate the rotor 12. A permanent magnet 27 is embedded in the opening of the main body. The magnet 27 may be made of gadolinium or ferrite, depending on the application destination of the machine 10 and the desired power. Alternatively, the poles of the rotor 12 may consist of coils.

On the other hand, the stator 11 is, for example, a main body 30 in the shape of a metal sheet package provided with a semi-closed type notch, and includes a main body 30 having a notch insulator for assembling the coil 31 of the stator 11. .. The coil 31 includes a series of phase windings that cross the notch of the main body of the stator 11 and form a front convex portion 32 and a rear convex portion 33 that project from both sides of the main body 30 of the stator 11. Here, the phase windings are obtained from conductor elements in the form of pins that are joined together, for example by welding. These spools are, for example, three-phase windings connected in one or more stars or one or more triangles. The outlet of the phase winding is coupled to a switch bridge and / or a rectifying bridge and / or an inverter with a diode or, in the case of a reversible machine 10, a MOSFET-type transistor.

The housing 16 includes a front bearing 36 and a rear bearing 37 assembled to each other. Bearings 36 and 37 are hollow and have ball bearings 38 and 39 in the center for the rotating assembly of the shaft 13, respectively. Alternatively, the spool is a magnetic spool. More precisely, the front bearing 36 comprises a nose 42 protruding from the side wall 43. A cylindrical wall 44 extends from the outer edge of the lateral wall 43. On the other hand, the rear bearing 37 has a side wall 47. The side wall 47 is provided with a hole that traverses the center thereof so as to allow the shaft 13 to pass through. The wall is provided with an annular span 48 intended to support the outer ring of the rear spool 39. Similarly, the rear bearing 37 comprises a cylindrical wall 49 extending from the outer edge of the lateral wall 43.

The rear bearing 37 is fixed to the front bearing 36 by a fixing mechanism 51 such as a screw or a rivet. The fixing mechanism 51 traverses an opening made in the annular edge 50 from the wall 48 to cooperate with a perforation (see FIG. 2) disposed within the thickness of the cylindrical wall 44 of the front bearing 36. ing.

In this case, the nose 42 is intended to work with the wall 57 of the envelope 21, specifically the hollow sleeve 56 having a corresponding shape extending from the inner lateral wall. The nose 42 forms an axial guide element with respect to the host element 20 of the machine 10 when it is inserted into the sleeve 56. Axial positioning of the machine 10 within the envelope 21 constitutes the outer surface of the lateral wall 43 of the front bearing 36 that constitutes an axial stopper intended to act as a (contact) support for the corresponding lateral wall 57 of the envelope 21. Is controlled by. The surface forming the stopper is included in the plane P1 perpendicular to the X-axis of the machine 10.

Further, the nose 42 forms a centering element of the machine 10 with respect to the envelope 21 of the host element 20. For this purpose, the nose 42 is provided with a surface 60 on its outer edge. This surface 60 is adjusted with respect to the sleeve 56 by, for example, an H7g6 type adjustment of 1/100 to 3/100 mm. One cross section of the nose 42 perpendicular to the axis (corresponding to the X axis) of the housing 16 that cuts the adjusting surface 60 exhibits a completely larger surface than the other cross section of the nose 42.

The nose 42 comprises a cylindrical wall that defines a space that allows the shaft 13 to pass through. Further, the nose 42 has an outer ring of the front spool 38 that cooperates with the surface of the corresponding span arranged on the inner edge of the nose 42. Further, the maximum cross section of the nose 42 is completely smaller than the cross section of the machine 10 included in the plane perpendicular to the X axis of the machine 10 that cuts the stator 11. In other words, the maximum outer diameter of the nose 42 located at the height of the adjusting surface 60 is smaller than the outer diameter of the front bearing 36 or the other part of the rear bearing 37.

As a modification, the guiding and centering functions of the machine 10 are separated and performed by two separate elements.

Similarly, the second portion 62 of the front bearing 36 ensures centering of the machine 10 with respect to the envelope 21. In this case, the second portion 62 comprises a portion of the cylindrical wall 44 of the front bearing 36 located at the height of the connection between the two bearings 36 and 37. The portion 62 comprises an adjusted surface of, for example, H7g6 type, adjusted to 1/100 to 3/100 mm with respect to the corresponding inner cylindrical surface of the envelope 21.

Therefore, when moving from the front end to the rear end of the machine 10, the front spool 38, the front convex portion 32, the front shaft end of the stator 11, the nose 42 to which the second centering portion 62 is mounted, and the rear spool 39 are sequentially found. Can be done.

Alternatively, the centering portion of the cylindrical wall 49 of the rear bearing 37 ensures the centering of the machine 10 with respect to the envelope 21. This portion comprises an adjusted surface of, for example, H7g6 type, adjusted to 1/100 to 3/100 mm with respect to the corresponding inner cylindrical surface of the envelope 21. Therefore, according to this modification, when the machine 10 is moved from the front end to the rear end, the front spool 38, the front convex portion 32, the front shaft end of the stator 11, and the centering portion of the cylindrical wall of the rear bearing are mounted on the nose. 42, and the rear spool 39 can be found in sequence.

The shaft 13 is provided with a rib in the central portion thereof for pressure fitting into the central perforated portion of the main body of the rotor 25. Further, when the machine 10 is inserted into the envelope 21, the adjusting portion 65 allows the shaft 13 to be rotationally driven from the opposite end side of the connecting mechanism 24. In this way, the teeth of the pinion 24 supported by the shaft 13 can be inserted into the space between the teeth of the corresponding pinions of the host element 20, which facilitates the connection of the machine 10 to the host element 20. For example, the adjustment portion 65 comprises at least two planes intended to work with a tool having the corresponding shape. The tool can be operated manually by the operator or, if desired, by an assembly chain robot.

On the other hand, as shown in FIG. 2, the electric machine 10 is cooled by the cooling circuit 68. The cooling circuit 68 is specifically designed to allow the coolant, in this example oil, to flow between the housing 16 and the body of the stator 30 in the X-axis direction.

For this purpose, the cooling circuit 68 includes a pump 69 that allows the coolant to be injected into the distribution chamber 70. The distribution chamber 70, which has an overall annular shape, is defined by a portion of the inner surface 72 of the envelope 21 and a portion of the wall 44 of the front bearing 36.

More precisely, the front bearing 36 comprises a peripheral recess 71 in the cylindrical wall 44. The recess 71 is defined by reduction in diameter of the cylindrical wall 44. The chamber 70 is defined by an outer surface of the recess 71 and an inner surface facing the inner wall of the envelope 21. The chamber 70 extends beyond the recess 71 into an annular space defined by the outer edge of the cylindrical portion of the front bearing 36 and the inner surface 72 of the envelope 21.

The chamber 70 is sealed from the rear end side by a seal 75 located in a groove 78 located on the outer edge of the front bearing 36. From the front end side, the outer surface of the side wall 43 functions as a support (abutment) to the corresponding plane of the side wall 57 of the envelope 21 so that the chamber 70 is watertight.

The chamber 70 communicates with a plurality of channels 76 (see FIG. 1) that extend axially between the stator 11 and the housing 16 for the passage of coolant. These channels 76 are regularly distributed at an angle over the peripheral surface of the stator 11. In one example of the embodiment, these channels 76 are formed by grooves located on the outer edge of the body of the stator 11 and are radially closed by the inner surface of the housing 16. As a modification, the configuration is reversed and a groove is created on the inner surface of the housing 16.

The housing 16 comprises a plurality of openings 77 to ensure fluid communication between the chamber 70 and the channel 76, each opening 77 appearing at one end of the outside of the machine 10 and within the distribution chamber 77. And emerge from the side of channel 76 at the other end. The plurality of openings 77 are arranged at an angle according to the peripheral portion of the housing 16.

Since the cross section of the different openings 77 changes depending on the angular position of the openings 77, the coolant can flow through each channel 76 at approximately the same pressure. Therefore, the farther the chamber 70 is from the oil injection zone 80, the larger the cross section of the different openings 77. Thus, over an angular opening of at least 100 degrees, especially 180 degrees, the opening 77 exhibits a crescent-shaped cross section as it moves away from the oil injection zone.

The openings 77 each exhibit an X1 axis (see FIG. 7b) extending parallel to the X axis of the machine 10 corresponding to the direction of flow of the coolant inside the channel 76. Preferably, the oil injection direction along the arrow F1 is tilted at an angle of, for example, at least 40 °, here approximately 90 degrees, with respect to the X1 axis of the opening 77. The liquid in the distribution chamber 70 is under pressure and preferably flows at an output of 3 to 8 liters per minute.

Therefore, as shown in FIGS. 7a and 7b, the oil injected according to the arrow F1 is uniformly dispersed inside the opening 77 on the outer periphery of the chamber 77 according to the arrow F2 so as to efficiently cool the machine 10. According to F3, the inside of the channel 76 flows axially over the peripheral surface of the stator 11.

Similarly, as shown in FIG. 1, the oil flows into the axial perforations 83 formed in the shaft 13 of the rotor 12 and the conduit 84 extending from the perforations 83 that open on both sides of the axial end of the rotor 12. Pass through the inside. Similarly, the shaft 13 includes at least one oil outlet 85 that opens facing the tank 88 disposed in the housing 16.

The tank 88 is suitable for receiving a coolant that also functions as a lubricating oil so as to ensure the lubricity of the front spool 38. When the electric machine 10 is mounted on the automatic vehicle, the tank 88 is located at the bottom of the machine 10 so that the lubricating oil can be stored in the tank 88 by gravity.

The tank 88 is configured to facilitate the flow of excess lubricating oil in the direction of the spool 38 when the tank 88 is full.

The tank 88 is defined by a bottom 89, a first side 91 formed by a radially oriented annular collar extending from the inner edge of the nose 42, and a second side 92 formed by the outer ring of the spool 38. Will be done. Therefore, a part of the spool 38 is in fluid contact with the lubricating oil of the tank 88. That is, at least a part of the spool 38 is in direct contact with the oil in the tank 88. The first side 91 is configured such that when the machine 10 is mounted on the host element 20, the lubricating oil can flow from the tank 88 to the spool 38, especially by gravity.

In this case, the height H1 of the first side portion with respect to the bottom portion 89 is higher than the height H2 of the second side portion 92 with respect to the bottom portion 89. The bottom 89 is slightly raised with respect to the surface span of the inner ring of the spool 38 and extends along its width along the X-axis direction of the machine 10.

The spool 38 does not have a side surface to facilitate the flow of oil in the spool 38. In addition, the spool 38 should have been degreased in advance and removed prophylactically so that the oil can easily flow through it without interfering with the grease contained in the spool due to its default. It is preferable to do so.

The cooling circuit 68 operates in a closed loop such that the oil is pumped out to a tank 95 outside the machine 10 and then pumped through the machine 10 and then returned to the tank 95.

As can be easily seen in FIG. 6, the rear bearing 37 is provided with openings 96 dispersed on its peripheral surface to allow oil to flow into the tank 95. As shown in FIGS. 3a, 3b and 4, the front bearing 36 is also provided with an opening 97 to allow oil to flow out into the tank 95.

The housing 16 is the angle of the machine 10 with respect to the envelope 21 when the machine 10 is inserted into the envelope 21 so as to ensure that the opening 97 is in a downward position to allow the liquid to flow to the outlet 97 by gravity. The alignment mechanism 100 is provided so as to allow the alignment.

In one example of the embodiment, the alignment mechanism 100 shown in FIGS. 3b, 4 and 5 comprises a platform made on the side wall 43 of the front bearing 36. The platform 100 is designed to be inserted into the correspondingly shaped perforations of the host element 20. The platform 100 may be offset with respect to the housing 16 or may be fixed to the housing 16. Further, the platform 100 is configured to allow the machine 10 to be blocked in rotation. For this purpose, the platform 100 exhibits a cross section that contributes to resisting at least a portion of the stress that the electromechanical machine 10 receives during operation.

As a variant, the coolant can take the form of oil and water emulsions as it also functions as a lubricating oil.

According to one embodiment, the output of the machine 10 can be included in 10 kW to 50 kW. The outer diameter of the rotor 12 is 8 to 14 cm, particularly 10 to 12 cm, preferably 11 cm. The outer diameter of the stator 11 is 10 to 20 cm, particularly 13 to 18 cm, preferably 15 cm.

Of course, the above description is for illustration purposes only and does not limit the field of the invention which is the same even when various elements are exchanged for other equivalents.

Claims (13)

-1 housing (16) and
-1 stator (11) and
-A plurality of channels (76) extending between the stator (11) and the housing (16) for the passage of coolant.
In the electric rotating machine (10) equipped with
The housing (16) comprises a plurality of openings (77).
Each of the openings opens to the outside of the electric rotating machine (10) at one end thereof and from the side of the channel (76) at the other end.
The housing (16) is at the periphery of the housing (16), which forms at least a portion of the coolant distribution chamber (70) when the electric rotating machine (10) is inserted into the host element (20). An electric rotating machine characterized by having a recess (71). The plurality of openings (77) are arranged at an angle according to the peripheral portion of the housing (16).
The electric rotating machine according to claim 1. The cross-sectional area of the plurality of openings (77) varies depending on the angular position of each of the openings (77) so that the coolant can flow through each channel (76) at approximately the same pressure. The electric rotating machine according to claim 1 or 2, wherein the electric rotating machine is characterized. Over an angle portion of at least 100 degrees, the opening (77) exhibits a crescent-shaped cross section.
The electric rotating machine according to claim 3. The housing (16) comprises a groove (78) on its outer wall intended to receive the seal (75).
The electric rotating machine according to any one of claims 1 to 4. Any one of claims 1-5, wherein the recess is defined by reduction in diameter of the cylindrical wall (44) of the housing (16) and / or is formed to extend in an annular shape. The electric rotating machine described in the section. An assembly comprising an envelope (21) of a host element (20) and an electrorotating machine (10) inserted into the envelope (21) according to any one of claims 1 to 6. .. The distribution chamber (70) is defined by a portion of the inner wall of the envelope (21) and a portion of the outer wall of the housing (16).
7. The assembly according to claim 7. The electric machine is the one according to claim 5.
The assembly comprises a seal (75) and the seal is placed in the groove to ensure closure of the distribution chamber (70).
The assembly according to claim 7 or 8. The housing (16) comprises a flat surface that acts as a support for the corresponding flat surface of the envelope (21) of the host element (20) so as to ensure that the distribution chamber (70) is watertight. ,
The assembly according to any one of claims 7 to 9. The opening (77) exhibits an axis extending along the axis of rotation of the electric rotating machine (10), respectively.
The assembly according to any one of claims 7 to 10. The oil injection direction is inclined with respect to the (X1) axis of the opening (77).
The assembly according to any one of claims 7 to 11. The liquid placed in the distribution chamber (70) is under pressure and flows at an output of 3 to 11 liters per minute.
The assembly according to any one of claims 7 to 12 , characterized in that.

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