JP2004320974A - Stator cooling structure - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a stator cooling structure of a double shaft multilayer motor which can be improved in cooling performance and increased in output power. <P>SOLUTION: The stator cooling structure of the multiple shaft multilayer motor is constituted so that an inner rotor 102 and an outer rotor 103 are concentrically arranged interposing a stator 101, and air gap parts of the rotor and the stator are composed of oil chambers, an oil drawing hole 207 penetrating the air gap part 206 of the inner rotor side and the air gap part 205 of the outer rotor side is formed to cool stator teeth 201, around which an coil is wound, from the inside and outside (the first invention). And also, it is constituted so that clearance is arranged between a stator core and coils, and a coolant is introduced into the clearance communicating with the outside from the inside of the stator (the second invention). <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a stator cooling structure for a multi-axis multi-layer motor applied to a hybrid drive unit or the like.

  Conventionally, in a multi-axis multi-layer motor in which an inner rotor and an outer rotor are arranged concentrically with a stator interposed therebetween, and an air gap formed by the rotor and the stator is formed by an oil chamber, the air gap is radially provided as a stator constituent member. Since the coil wound around the stator teeth thus generated generates heat, it is necessary to cool the stator.

As a stator cooling structure for such a multi-axis multilayer motor, a tooth cooling passage through which cooling water can be circulated is arranged between stator teeth that are radially provided as stator constituent members, and the cooling is performed in the tooth cooling passage. 2. Description of the Related Art A stator cooling structure that cools a stator by flowing water has been known (for example, see Patent Document 1).
JP-A-2000-14086 (Claim 1, FIG. 1)

  However, in the above-described stator cooling structure, since the cooling means of the stator teeth around which the coil as the heat source is wound is only the teeth cooling passage arranged between the teeth, the output of the multi-axis multilayer motor is further improved. For this purpose, it was necessary to add a further cooling means or to study another cooling means with high efficiency.

  Conventionally, since the position of the air gap portion of the inner rotor and the seal portion of the cooling water channel system are located at substantially the same position in the radial direction, the air gap of the outer rotor from the air gap portion of the inner rotor to parts other than the stator teeth. Even if the bypass passage to the gap portion is provided, it will be disposed inside the position of the air gap portion of the inner rotor, and the oil will always remain in the region from the air gap portion of the inner rotor to the bypass passage, This was causing friction.

  It is an object of the first invention of the present invention to provide a stator cooling structure for a multi-axis multilayer motor that advantageously solves the above-mentioned problems, and the stator cooling structure of the present invention is concentric with a stator interposed therebetween. In a stator cooling structure of a multi-shaft multilayer motor in which an inner rotor and an outer rotor are arranged and an air gap between the rotor and the stator is constituted by an oil chamber, the stator teeth include an inner rotor-side air gap and an outer. An oil vent hole penetrating through the air gap portion on the rotor side is provided so that the stator teeth around which the coil is wound can be cooled from inside and outside.

  Another object of the present invention is to provide a stator cooling structure for a multi-axis multilayer motor that advantageously solves the above-mentioned problems. In a stator cooling structure of a multi-axis multi-layer motor composed of a stator composed of stator cores arranged in a circle, and an inner rotor and an outer rotor arranged concentrically with the stator interposed therebetween, a gap is formed between the stator core and the coil. The cooling liquid is guided to a gap communicating from the inside to the outside of the stator.

  In the first invention of the stator cooling structure of the present invention, as a cooling means for the stator teeth on which the coil as the heat source is wound, an oil penetrating the teeth through the air gap portion of the outer rotor and the air gap portion of the inner rotor. By providing a hole and cooling by passing oil through the hole, the cooling performance can be improved, and the output can be further improved.

  In a preferred embodiment according to the first invention of the stator cooling structure of the present invention, oil drain holes provided in the stator teeth are formed such that adjacent holes are provided at equal intervals in the axial direction, and holes are formed from ends of the stator teeth. May be provided at a position that is half the pitch between holes. With this configuration, the oil drain holes are arranged at equal intervals, and the distance from the end of the stator teeth to the hole is provided at a position that is half the pitch between the holes. As a result, the cooling oil passages are present evenly, and the variation in the cooling performance of the stator teeth can be reduced.

  In a preferred embodiment of the first invention of the stator cooling structure of the present invention, the stator teeth are arranged such that the oil passage hole located at the center reduces the magnetic flux passage area and increases the peripheral magnetic flux density. Alternatively, the teeth width may be configured so as not to saturate the magnetic flux. With this configuration, even when the magnetic flux density increases due to the reduction of the magnetic flux passage area due to the installation of the oil drain hole, a magnetic flux passage area that does not cause magnetic flux saturation is secured. The output does not decrease due to.

  In the second invention of the stator cooling structure of the present invention, since both the stator core and the coil, which are the heating elements, can be directly cooled, the cooling efficiency is improved. Further, conventionally, where the heating elements are adjacent to each other, since a cooling passage is provided between the two heating elements, a local temperature rise caused by the densely arranged heating elements is reduced. be able to.

  In a preferred embodiment according to the second invention of the stator cooling structure of the present invention, as the stator, an insulating member wider than the core circumferential direction is disposed at the end of the stator core in the stacking direction, and the coil is wound thereon. By doing so, a stator having a gap for guiding the coolant to the side surface of the core may be used. According to this structure, in addition to the effect of the second aspect described above, a cooling passage extending from the inside to the outside of the stator by merely changing the size of the insulating member currently used at the end of the stator core in the stacking direction. The cooling efficiency can be increased without increasing the number of parts and processes.

  In a preferred embodiment according to the second invention of the stator cooling structure of the present invention, among the insulating members arranged on the axial side surface of the stator core and the end portions in the core stacking direction as the stator, the insulating member on the axial side surface of the stator core is provided. A stator may be used in which a gap for guiding the coolant is formed between the stator core and the stator core. According to this structure, in addition to the effect of the second aspect described above, the insulating member on the side surface in the axial direction of the stator and the side surface of the stator core form a cooling passage, and the cooling passage is formed by changing the shape of the insulating member. Can be freely changed, so that a cooling passage that generates a turbulent flow having a heat transfer coefficient that is overwhelmingly higher than a laminar flow can be formed, and cooling can be performed efficiently.

  Furthermore, in a preferred embodiment according to the second invention of the stator cooling structure of the present invention, by forming a stator core by stacking cores having different core circumferential widths as a stator, a cooling fluid is provided between the stator core and the coil. May be used. According to this structure, in addition to the effect of the second aspect described above, there is no need to increase the size in the core circumferential direction, and a core having a smaller circumferential size than the conventional stator core is combined with the conventional stator core. Since the layers are stacked, the space factor can be increased and the power density can be improved.

  Furthermore, in a preferred embodiment according to the second invention of the stator cooling structure of the present invention, a stator having a mechanism for regulating a position of a coil in a radial direction relative to a stator core may be used as the stator. According to this structure, in addition to the effects of the above-described second invention and its preferred embodiments, when the cross section perpendicular to the lamination direction of the stator core is T-shaped, a cooling passage is formed from the inside to the outside of the stator. The position of the coil relative to the stator core can be regulated, and the shape of the cooling passage is maintained almost uniformly in all cores without disturbing the shape of the cooling passage at the time of assembling or molding. Can be made almost uniform.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.
FIG. 1 is an overall view of a hybrid drive unit to which a multi-shaft multi-layer motor is applied. In FIG. 1, E is an engine, M is a multi-shaft multi-layer motor, G is a Ravigneaux type compound planetary gear train, D is a drive output mechanism, 1 is a motor cover, 2 is a motor case, 3 is a gear housing, and 4 is a front cover.

  The engine E is a main power source of the hybrid drive unit, and the engine output shaft 5 and the second ring gear R2 of the Ravigneaux-type compound planetary gear train G are connected via a rotation fluctuation absorbing damper 6 and a multi-plate clutch 7. ing.

  The multi-shaft multi-layer motor M is a single motor in appearance, but is a sub power source having two motor generator functions. The multi-axis multi-layer motor M is fixed to the motor case 2 and has a stator S as a fixed armature wound with a coil, an inner rotor IR disposed inside the stator S and having a permanent magnet embedded therein, The outer rotor OR having the permanent magnets embedded therein and the outer rotor OR arranged outside the S are coaxially arranged in three layers. A first motor hollow shaft 8 fixed to the inner rotor IR is connected to a first sun gear S1 of a Ravigneaux-type compound planetary gear train G, and a second motor shaft 9 fixed to the outer rotor OR is a Ravigneaux-type compound planetary gear. It is connected to the second sun gear S2 in the row G.

  The Ravigneaux type compound planetary gear train G is a planetary gear mechanism having a continuously variable transmission function of continuously changing a transmission ratio by controlling two motor rotation speeds. The Ravigneaux type compound planetary gear train G includes a common carrier C that supports a first pinion P1 and a second pinion P2 that mesh with each other, a first sun gear S1 that meshes with the first pinion P1, and a second sun gear that meshes with the second pinion P2. It has five rotating elements: S2, a first ring gear R1 meshing with the first pinion P1, and a second ring gear R2 meshing with the second pinion P2. A multi-plate brake 10 is interposed between the first ring gear R1 and the gear housing 3. An output gear 11 is connected to the common carrier C.

  The drive output mechanism D includes an output gear 11, a first counter gear 12, a second counter gear 13, a drive gear 14, a differential 15, and drive shafts 16, 16. The output rotation and output torque from the output gear 11 pass through the first counter gear 12 → second counter gear 13 → drive gear 14 → differential 15 and are transmitted from the drive shafts 16, 16 to drive wheels (not shown). You.

  That is, the hybrid drive unit connects the second ring gear R2 to the engine output shaft 5, connects the first sun gear S1 to the first motor hollow shaft 8, and connects the second sun gear S2 and the second motor shaft 9 to each other. And the output gear 11 is connected to the common carrier C.

  FIG. 2 is a diagram showing in more detail one example of a multi-shaft multi-layer motor to which the present invention is applied, which constitutes a vehicular hybrid transmission in combination with a Ravigneaux type planetary gear train. The stator cooling structure of the present invention can be applied to this multi-shaft multilayer motor. The multi-shaft multilayer motor having the configuration shown in FIG. 2 includes a single annular stator 101, and an inner rotor 102 rotatably disposed radially inward and outward on a predetermined rotation axis O coaxial with each other. The outer rotor 103 has a triple structure, and these are housed in a housing 104.

  Each of the inner rotor 102 and the outer rotor 103 has laminated cores 124 and 125 which are formed by laminating a plate material formed by pressing an electromagnetic steel plate or the like in the axial direction of the rotor. The permanent magnets penetrating in the direction are arranged at equal intervals in the circumferential direction. The number of pole pairs of the inner rotor 102 and the outer rotor 103 is made different by changing the number of magnetic poles arranged. As an example, the number of magnets is the same for the inner rotor 102 and the outer rotor 103, and is 12 each. However, since the inner rotor 102 forms one pole with two magnets, the number of pole pairs is Are three pole pairs, and the outer rotor 103 forms one pole with one magnet, so the number of pole pairs is six pole pairs.

  When the inner rotor 102 and the outer rotor 103 are stored in the housing 104, the outer rotor 103 is provided with a torque transmission shell 105 drivingly connected to the outer periphery of the laminated core 125, and both ends of the torque transmission shell 105 are bearings. The housing 107 is rotatably supported by the housing 104 and the torque transmission shell 105 is coupled to the outer rotor shaft 109 on the bearing 107 side.

  The inner rotor 102 is provided at the center of the laminated core 124 with a hollow inner rotor shaft 110 penetrating the outer rotor shaft 109 rotatably inside the laminated core 124, and between the laminated core 124 and the inner rotor shaft 110 of the inner rotor 102. Drive coupling. An intermediate portion of the inner rotor shaft 110 is rotatably supported in a fixed stator bracket 113 by a bearing 112, and one end (the left end in FIG. 1) is rotatable by a bearing 114 on a corresponding end wall of the torque transmission shell 105. To support.

  The stator 101 includes a plurality of stator pieces formed by laminating an I-shaped stator steel plate formed by pressing an electromagnetic steel plate in the axial direction of the stator. As shown in FIG. 2, an electromagnetic coil 117 is wound around each of the stator pieces at the teeth between the outer rotor-side yoke and the inner rotor-side yoke, and these coil-wound stator pieces are equally spaced in the same circumferential direction. That is, the stator core is arranged in a circular shape to form a stator core. The stator core is sandwiched between brackets 113 and 118 on both sides in the axial direction of the stator by bolts 119 and is entirely molded with a resin 120 to integrally form the stator 101. . A coolant passage 141 is formed in the resin 120 between the adjacent stator pieces 116 in the axial direction, and the bolts 119 are located radially inward and outward of the coolant passage 141, respectively. Here, each bolt 119 is tightened by a nut 119a screwed thereto. Needless to say, the tightening structure using bolts and nuts may be a tightening structure using rivet pins.

  In driving the motor, the rotation positions of the inner rotor 102 and the outer rotor 103 detected by the rotation sensor 148 and the rotation sensor 147, that is, both rotors 102 and 103 corresponding to the positions of the permanent magnets provided as described above. A composite current obtained by combining drive currents having different phases is supplied to the electromagnetic coil 117 of the stator 101, and thereby the rotating magnetic fields for both the rotors 102 and 103 are individually generated in the stator, thereby generating a rotating magnetic field. The rotors 102 and 103 can be individually driven to rotate synchronously.

  FIGS. 3 and 4 are diagrams for explaining an example of the stator cooling structure of the multi-shaft multilayer motor according to the first invention of the present invention. In the example shown in FIG. 3, a coolant passage 141 is already provided in the stator 101 for removing heat generated from the coil 117 wound around the stator 101. The first invention of the present invention is characterized in that, in addition to the coolant passage 141, the stator teeth 201 have an oil drain that radially penetrates the air gap 206 on the inner rotor side and the air gap 205 on the outer rotor side. The point is that the holes 207 are provided so that the stator teeth 201 around which the coils 202 are wound can be cooled from inside and outside. In the present embodiment, the cooling structure according to the first invention of the present invention is applied to a stator having a cooling passage 141 for cooling by inserting water as a cooling liquid, for example. It is needless to say that the application of the present invention is effective. The details will be described below.

  In the example shown in FIGS. 3 and 4, a coil 202 is wound around a stator tooth 201 formed by laminating electromagnetic steel plates in the axial direction, and a cooling pipe (with a cooling water passage therein between adjacent stator teeth 201). A coolant passage 141 is provided. Stator teeth 201 formed by laminating electromagnetic steel plates in the axial direction are fixed in the axial direction by bolts 204 disposed inside and outside the cooling pipe 141 to form the stator 101. An oil drain hole 207 penetrating between the air gap 205 on the outer rotor 103 side and the air gap 206 on the inner rotor 102 side is provided at the center of the stator teeth 201.

  The oil in the inner rotor cooling oil passage 208 flows out of the seal ring portion 209 with a limited flow rate, and reaches the air gap portion 206 on the inner rotor 102 side via the gap portions 210 and 211. The oil retained in the air gap portion 206 on the inner rotor 102 side is subjected to centrifugal force by the rotation of the inner rotor 102, and reaches the air gap portion 205 on the outer rotor 103 side via the oil drain hole 207. The oil that has accumulated in the air gap portion 205 on the outer rotor 103 side is subjected to centrifugal force by the rotation of the outer rotor 103, and is discharged to the outside of the rotor from through holes 212 and 213 provided on both axial sides of the outer rotor 103. .

  In the stator cooling structure of the multi-shaft multi-layer motor according to the first invention of the present invention having the above-described configuration, the heat generated from the coil 117 is not only suppressed by the cooling water circulating through the cooling liquid passage 141 provided between the stator teeth 201, but also In addition, oil that passes through the air gap 206 on the inner rotor 102 side and the air gap 205 on the outer rotor 103 side and passes through the oil drain hole 207 provided in the stator teeth 201 can be suppressed. As a result, in the multi-shaft multilayer motor, the cooling performance can be improved, and the output can be further improved.

  The position where the oil drain hole 207 is provided is not particularly limited, but it is preferable to provide the oil drain hole 207 at all locations in the stator teeth 201 as shown in FIG. As shown in FIG. 4, adjacent oil holes are provided at regular intervals in the axial direction of the oil drain hole 207, and the oil drain hole 207 is located immediately near the axial end of the stator teeth 201 (the left end in FIG. 3). Is preferably provided at a position that is half the pitch between the other holes. With such a configuration, the cooling oil passages are present evenly in the axial direction, and variations in the cooling performance of the stator teeth can be reduced.

  Further, it is preferable that the teeth width of the stator teeth 201 is such that the magnetic flux passage area is reduced by the oil drain hole 207 disposed in the center portion and the magnetic flux does not saturate even when the peripheral magnetic flux density increases. In FIG. 4 showing a cross section of oil drain hole 207 provided in stator 101, the ratio of width B of oil drain hole 207 to tooth width A corresponds to the rate of increase of the magnetic flux density passing through stator teeth 201 in the radial direction. However, by setting the width of the oil draining hole 207 so that the magnetic flux density in the increased state is equal to or less than the saturation magnetic flux density of the laminated electromagnetic steel sheet constituting the stator teeth 201, the magnetic flux caused by the oil draining hole 207 is provided. No reduction occurs and no output reduction occurs.

  In the examples shown in FIGS. 3 and 4, only members related to the stator cooling structure of the present invention are denoted by reference numerals, but other members constituting the multi-axis multilayer motor are denoted by reference numerals. Even if it is not provided, it is basically the same as the example shown in FIG. In addition, the present invention is not limited to the above-described examples. For example, it is obvious that the position and the number of the oil drain holes 207 are not limited to these examples.

  Next, a second invention of the stator cooling structure of the present invention will be described. FIG. 5 is a view for explaining an example of the stator cooling structure according to the second invention of the present invention. In the second invention of the present invention shown in FIG. 5, a multi-axis multi-layer motor to which the stator cooling structure according to the second invention of the present invention is applied has a stator 311 comprising a stator core 301 provided with a coil 302 and arranged in a circle. And an inner rotor 303 and an outer rotor 304 arranged concentrically with the stator 311 interposed therebetween.

  A feature of the stator cooling structure according to the second invention of the present invention is that a gap 308 is provided between the stator core 301 and the coil 302, and from the inside to the outside of the stator 311, that is, the inner air gap 305 is provided through the gap 308. The configuration is such that the cooling liquid is introduced from the outer air gap 306 to the outer air gap 306. In this example, the cooling liquid supplied to the inner gap 305 between the inner rotor 303 and the stator 311 is supplied to the stator core 301 by the centrifugal force of the inner rotor 303 and the outer rotor 304 and the pressure difference between the inner and outer circumferences of the stator 311. Then, it passes through the gap 308 between the coil and the coil 302 and is led to the outer end gap 306 while removing heat from the heating element. In addition, 309 is a bolt used for fixing.

  FIGS. 6A to 6C are views for explaining the first embodiment of the cooling passage in the second invention of the present invention. Here, FIG. 6A is a view of the stator core 301 as viewed from the teeth end, FIG. 6B is a cross-sectional view of the stator core 301 in the teeth circumferential direction (core circumferential direction), and FIG. The figure seen from the teeth side of the stator core 301 is shown, respectively. In the first embodiment of the cooling passage shown in FIGS. 6A to 6C, a gap 308 is formed between the side surface of the stator core 301 and the coil 302, and is used as a cooling passage. That is, the sleeper 307 of an insulating member wider than the core circumferential width 301W of the stator core 301 is disposed at the end of the stator core 301 in the stacking direction, and the coil 302 is wound thereon, thereby cooling the side surface of the stator core 301. A gap 308 for guiding the liquid is formed.

  FIGS. 7A to 7C are views for explaining a second embodiment of the cooling passage in the second invention of the present invention. Here, FIG. 7A is a diagram viewed from a tooth end of the stator core 301, FIG. 7B is a cross-sectional view of the stator core 301 in a tooth circumferential direction (core circumferential direction), and FIG. The figure seen from the teeth side of the stator core 301 is shown, respectively. In the second embodiment of the cooling passage shown in FIGS. 7A to 7C, the insulating member 307 (the insulating member 307a at the end, the insulating member 307a at the end, disposed at the end in the core lamination direction and the side in the core axial direction of the stator core 301). In the insulating member 307b), a gap 308 is formed between the insulating member 307b arranged on the side surface in the core axial direction and the core side surface of the stator core 301, and this is used as a cooling passage. At this time, by providing irregularities on the insulating member 307b on the side surface in the core axial direction, turbulent flow with good heat transfer efficiency can be generated.

  FIGS. 8A to 8C are views for explaining a third embodiment of the cooling passage in the second invention of the present invention. Here, FIG. 8A is a view of the stator core 301 as viewed from a tooth end, FIG. 8B is a cross-sectional view of the stator core 301 in a tooth circumferential direction (core circumferential direction), and FIG. The figure seen from the teeth side of the stator core 301 is shown, respectively. In the third embodiment of the cooling passage shown in FIGS. 8A to 8C, cores having different widths in the circumferential direction (core circumferential direction) (here, a core 301-1 having a large width and a core 301-having a small width). By forming the stator core 301 by laminating 2), a gap 308 for guiding the coolant is formed on the side surface of the stator core 301. By doing so, it is possible to optimize the shape of the cooling passage by changing the number of stacked cores (core 301-1 or core 301-2) without producing a part having a new shape. Can be reduced.

  In the embodiment described above, it is preferable to provide a mechanism for regulating the relative radial position of the coil 302 with respect to the stator core 301 so that the cooling passage can be secured even when the core shape is T-shaped. For example, as shown in FIG. 9, it is preferable that a spacer 312 is partially arranged between the stator core 301 and the coil 302 to fix the position of the coil 302 with respect to the stator core 301 in the direction of the arrow.

  Hereinafter, a specific embodiment for assembling the above-described stator core 301 as a stator will be described.

  FIG. 10 is a view for explaining an example of a stator core fixing structure by swaging using a comb frame. In the example shown in FIG. 10, the frame 401 of the comb-shaped stator has a portion connected in a circular shape at the end portion in the axial direction of the stator, and a plate-shaped portion extending in the axial direction from the inner and outer circumferences of the circular portion. (The inner plate portion 402 and the outer plate portion 403) are integrally formed. This frame 401 is provided with the same number of slots as the number of split stator cores 301 to be mounted. The stator core 301 is arranged in each slot, and the plate-shaped portions 402 and 403 extending in the axial direction of the stator forming the slots are pressed and crimped from the inner and outer circumferences of the stator, thereby fixing the divided stator core 301 and the frame 401 to fix the stator. Form. At this time, relief portions 404 and 405 are formed in each of the plate portions 402 and 403 of the frame 401 so as to form a gap extending from the inside to the outside of the stator. The cooling fluid flows in the order of the escape portion 404 provided on the inner plate portion 402, the clearance 308 of the stator core 301, and the escape portion 405 provided on the outer plate portion 403, thereby providing a cooling passage from the inside to the outside of the stator. Can be formed.

  FIG. 11 is a diagram for explaining an example of a stator core fixing structure by an elastic force using a comb frame. In the example shown in FIG. 11, a comb-shaped stator frame 501 has a portion connected in a circular shape at an end in the stator axial direction, and a columnar portion having a taper angle extending in the axial direction from the circumference of the circular portion. And 502 are formed as an integral body. Further, the shape of the inner peripheral end of the stator core 301 is shaped to engage with the space formed by the taper angle between the adjacent plate-shaped portions 502. This frame 501 has the same number of slots as the number of split stator cores 301 to be mounted. When the stator core 301 is arranged so as to be pushed into each slot, a force for pushing the stator core 301 outward acts due to the elastic force and the taper angle of the plate portion 502. A portion to be spread outward is pressed by the ring-shaped member 503 from the outer periphery of the stator, thereby fixing the stator core 301 with the elastic force of the member forming the stator to form the stator. At this time, a gap 504 extending from the inside to the outside of the stator is formed in the plate portion 502 on the inner periphery of the frame 501. By flowing the coolant in the order of the gap 504 provided in the inner plate-shaped portion 502 and the gap 308 of the stator core 301, a cooling passage from the inside to the outside of the stator can be formed.

  FIG. 12 is a simplified diagram showing an example of a frame 501 used in FIG. In the example shown in FIG. 12, the same members as those shown in FIG. 11 are denoted by the same reference numerals, and description thereof will be omitted. In the example shown in FIG. 12, reference numeral 505 denotes a circular connecting portion which is circularly connected at the inner end in the axial direction of the stator constituting the frame 501.

  The stator cooling structure of the present invention is a multi-axis multilayer motor in which an inner rotor and an outer rotor are arranged concentrically with a stator interposed therebetween, and it is necessary to cool the stator, in particular, a stator core and a coil constituting the stator. It can be suitably used for a certain multi-axis multilayer motor.

1 is a schematic overall view showing a hybrid drive unit to which a multi-axis multilayer motor is applied. 1 is a longitudinal sectional side view showing a multi-shaft multi-layer motor having a stator cooling structure of the present invention, which is combined with a Ravigneaux type planetary gear train to constitute a vehicle hybrid transmission. FIG. 1 is a longitudinal sectional side view for explaining an example of a stator cooling structure of a multi-axis multilayer motor according to a first invention of the present invention. FIG. 4 is a vertical sectional front view of a stator cooling structure of the double-shaft multilayer motor shown in FIG. 3. It is a figure for explaining an example of a stator cooling structure concerning a 2nd invention of the present invention. (A)-(c) is a figure for demonstrating 1st Example of the cooling passage in the 2nd invention of this invention, respectively. (A)-(c) is a figure for each explaining 2nd Example of the cooling passage in the 2nd invention of this invention. (A)-(c) is a figure for each explaining 3rd Example of the cooling passage in the 2nd invention of this invention. It is a figure for explaining position regulation of a coil in a stator cooling structure concerning a 2nd invention of the present invention. It is a figure for explaining an example of a stator core fixing structure by caulking using a comb type frame. It is a figure for explaining an example of a stator core fixing structure by elastic force using a comb type frame. FIG. 12 is a simplified diagram illustrating an example of a frame used in FIG. 11.

Explanation of reference numerals

DESCRIPTION OF SYMBOLS 101 Stator 102 Inner rotor 103 Outer rotor 201 Stator teeth 202 Coil 204 Bolt 205 Outer rotor side air gap part 206 Inner rotor side air gap part 207 Oil drain hole 208 Inner rotor cooling oil passage 209 Seal ring part 210, 211 Air gap part 212, 213 Through hole 301 Stator core 302 Coil 303 Inner rotor 304 Outer rotor 305 Inner air gap 306 Outer air gap 307, 307a, 307b Sleeper 308, 504 Gap 309 Bolt 311 Stator 312 Spacer 401, 501 Frame 402, 402, 502 Plate shape Parts 404, 405 relief part 503 ring-shaped member 505 circular connection part

Claims (8)

  In a stator cooling structure of a multi-axis multi-layer motor in which an inner rotor and an outer rotor are arranged concentrically with a stator interposed therebetween, and an air gap between the rotor and the stator is constituted by an oil chamber, a stator tooth is provided on an inner rotor side. A stator cooling structure characterized in that an oil drain hole is provided through the air gap portion and the air gap portion on the outer rotor side so that the stator teeth around which the coil is wound can be cooled from inside and outside.   Oil drain holes provided in the stator teeth are such that adjacent holes are provided at equal intervals in the axial direction, and the distance from the end of the stator teeth to the hole is provided at a position half the pitch between the holes. The stator cooling structure according to claim 1.   3. The stator according to claim 1, wherein the stator teeth have a tooth width that does not saturate the magnetic flux even when the magnetic flux passage area is reduced by the oil drain hole arranged at the center and the peripheral magnetic flux density is increased. 4. Cooling structure.   In a stator cooling structure of a multi-axis multi-layer motor comprising a stator comprising a stator core provided with a coil and arranged in a circular shape, and an inner rotor and an outer rotor arranged concentrically with the stator interposed therebetween, a stator core and a coil are provided. A cooling fluid is introduced into the gap communicating from the inside to the outside of the stator.   As the stator, an insulating member wider than the circumferential width of the core is disposed at the end of the stator core in the stacking direction, and a coil is wound therefrom to form a gap for guiding the coolant to the side surface of the core. The stator cooling structure according to claim 4.   Claims: As a stator, a stator having a gap for guiding a coolant between an insulating member on an axial side surface of a stator core and a stator core among insulating members arranged on an axial side surface of the stator core and an end portion in a core stacking direction. 5. The stator cooling structure according to 4.   The stator cooling structure according to claim 4, wherein the stator has a gap in which a coolant is introduced between the stator core and the coil by forming a stator core by stacking cores having different core circumferential widths.   The stator cooling structure according to any one of claims 4 to 7, wherein a stator having a mechanism for regulating a position of a coil in a radial direction relative to a stator core is used as the stator.

Images