JP2014072921A - Rotary electric machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a rotary electric machine at low cost that can cool a stator with a simple configuration.SOLUTION: An electric motor 1 comprises a stator 13 fixed to a motor housing HU and a rotor 14 arranged inward in a radial direction facing the stator 13. The rotor 14 is formed by holding both end surfaces of a rotor core 14a between a pair of holding plates 14b, 14c. In each of the holding plates 14b, 14c, a first oil catcher 14b1 and a second oil catcher 14c1 are projected in a rotation axis direction respectively on an end surface not abutting on the rotor core 14a. Each of the oil catchers 14b1, 14c1 linearly extends in a radial direction from near an inner peripheral end and an outer peripheral end of the holding plates 14b, 14c. When the rotor 14 rotates, the oil catchers 14b1, 14c1 can hold oil in the motor housing HU and flip it up in a rotation direction of the rotor 14.

Description

  The present invention relates to a rotating electric machine including an electric motor and a generator.

  A rotating electrical machine such as a motor includes a stator in which a plurality of coils are arranged on the circumference in order to generate a rotating magnetic field. However, when the motor operates, the stator generates heat due to iron loss of the stator core or copper loss of the stator coil. The heat generated in the stator may lead to a decrease in the insulation performance of the stator coil, which may lead to motor burnout. Further, the heat generated in the stator is transmitted to the motor shaft and the bearing through the housing and increases the friction at the time of rotation, leading to a reduction in the operating efficiency of the motor. Furthermore, the heat of the stator is also transmitted to other members of the motor, which may reduce the durability of each member. Therefore, conventionally, cooling the stator core and the stator coil has been a major technical problem in order to improve the durability of the motor and to operate the motor efficiently.

  In order to improve the cooling performance of the stator coil, there has been a related art related to a cooling device for a rotating electrical machine that supplies cooling oil that has passed through the rotating shaft to the coil end of the stator coil (see, for example, Patent Document 1). In the cooling device according to the related art, a cylindrical flange portion is protruded toward the coil end from the peripheral end portion of the end plate fixed to the rotor core, and the surface of the flange portion facing the coil end is undulated to form a refrigerant. A diffusion surface is formed. The cooling oil that has passed through the refrigerant holes provided in the end plate is diffused on the refrigerant diffusion surface of the flange portion, and cools the coil end from many directions.

JP 2009-296772 A

However, in the cooling device for a rotating electrical machine disclosed in Patent Document 1 described above, it is necessary to form an oil passage in a rotating shaft, an end plate, or the like in order to allow cooling oil to pass through. In order to form an oil passage in an end plate or the like, it is necessary to process each member in a complicated manner, which complicates the manufacturing process and increases manufacturing effort.
In addition, in order to circulate the cooling oil in the rotating electrical machine, a hydraulic pump and piping for pumping the cooling oil are required, and the manufacturing cost is increased due to the complicated manufacturing process described above. It was.
The present invention has been made in view of the above circumstances, and an object thereof is to provide a low-cost rotating electrical machine capable of cooling a stator with a simple configuration.

  In order to solve the above-described problems, an invention of a rotating electrical machine according to a first aspect of the present invention includes a housing in which cooling oil is stored, and fixed to the housing, and wound around the stator core so that a plurality of coils are arranged on the circumference. A rotated stator and a rotor rotatably mounted in the housing and facing radially inward with respect to the stator, and the rotor is formed by laminating a plurality of core plates in the rotation axis direction A rotor core, and a pair of end plates sandwiching both end surfaces in the stacking direction of the rotor core, and at least one of the end plates protrudes in the direction of the rotation axis on the end surface not in contact with the rotor core, This is because the oil-raising part capable of repelling the cooling oil by the rotation of the rotor is formed to extend in the radial direction.

  According to a second aspect of the present invention, in the rotating electric machine according to the first aspect, the oil lifting unit is formed in a curved line so as to move in the rotational direction of the rotor as it goes radially outward. is there.

  According to a third aspect of the present invention, in the rotating electric machine according to the first or second aspect, the oil raking unit is formed by pressing the end plate in the thickness direction.

  According to a fourth aspect of the present invention, in the rotating electric machine according to any one of the first to third aspects, the inner peripheral surface of the housing has an arc shape around the rotation axis, and rotates toward the end surface of the rotor or the stator. That is, a repellent portion protruding in the axial direction is formed.

According to the rotating electrical machine of the first aspect, at least one of the end plates protrudes in the direction of the rotation axis on the end surface that is not in contact with the rotor core, and the oil is pumped up so that the cooling oil can be repelled by the rotation of the rotor. When the rotor is driven by forming the portion so as to extend in the radial direction, the cooling oil stored in the housing is repelled by the oil lifting unit. The splashed cooling oil scatters outward in the radial direction by centrifugal force and is supplied to the stator exposed on the cooling oil in the housing, so that the stator can be efficiently cooled.
Therefore, it is not necessary to process each member in a complicated manner only by projecting the oil lifting portion on the end plate, and the rotating electrical machine can be easily manufactured. Further, a pump or piping for cooling the stator is unnecessary, and a small and low-cost rotating electrical machine can be obtained.

  According to the rotary electric machine according to claim 2, the oil lifting unit is formed in a curved line so as to move in the rotational direction of the rotor as it goes radially outward. As a result, the cooling oil stored in the lower portion of the housing can be easily repelled, and the cooling performance of the stator by the cooling oil can be further improved.

  According to the rotary electric machine according to claim 3, since the oil lifting unit is formed by pressing the end plate in the thickness direction, the oil lifting unit is formed on the end plate in a short time in the manufacturing process. be able to.

  According to the rotary electric machine according to claim 4, the inner peripheral surface of the housing is formed with a repellent portion that has an arc shape around the rotation axis and projects in the direction of the rotation axis toward the end surface of the rotor or the stator. As a result, the cooling oil splashed up by the oil lifting portion and scattered in the housing direction is repelled on the end plate by the return portion. Therefore, since the repelled cooling oil is repelled again by the oil lifting unit and supplied to the stator, the cooling performance of the stator can be further improved.

Sectional drawing which showed the state mounted in the vehicle of the electric motor by Embodiment 1 of this invention External perspective view of the rotor shown in FIG. Front view of rotor The front view which looked at the state where the rotor was stored in the motor housing from the 2nd holding plate side External perspective view of rotor according to embodiment 2 Front view of rotor according to embodiment 3 Front view of rotor according to embodiment 4

<Embodiment 1>
Based on FIG. 1 thru | or FIG. 4, the electric motor 1 (corresponding to a rotary electric machine) by Embodiment 1 of this invention is demonstrated. The electric motor 1 is a synchronous motor for driving wheels in a hybrid vehicle. However, the present invention should not be limited to this, and can be applied to any electric motor such as a motor provided in a home electric appliance or a motor for driving a general industrial machine.

  In the description, the direction of the rotational axis or the axial direction means the direction along the rotational axis C of the electric motor 1, that is, the left-right direction in FIG. In FIG. 1, the left side is sometimes referred to as the front of the electric motor 1 and the right side is sometimes referred to as the rear, but is not related to the actual direction on the vehicle.

  As shown in FIG. 1, the motor case 11 includes a rotor 14 and a stator 13 (both will be described later) of the electric motor 1 and the front is sealed with a motor cover 12. A clutch inner 21 included in the clutch device 2 (which is outside the configuration of the present invention), which is a wet multi-plate clutch, is rotatably attached to the motor cover 12 via a bearing 12a. Moreover, the clutch outer 22 of the clutch apparatus 2 is rotatably supported by the motor case 11 by the bearing 11a. The configuration including the motor case 11 and the motor cover 12 corresponds to a housing. Hereinafter, the configuration is referred to as a motor housing HU.

  A crankshaft of a vehicle engine (not shown) is connected in front of the clutch inner 21. The clutch outer 22 is spline-fitted to the input shaft 3 of a vehicle transmission (not shown) at the inner peripheral end. The clutch device 2 is a normally closed type clutch device that normally connects the engine and the electric motor 1 by connecting a clutch inner 21 and a clutch outer 22. When hydraulic pressure is supplied to the clutch device 2, the connection between the clutch inner 21 and the clutch outer 22 is released, and torque transmission between the engine and the electric motor 1 is interrupted.

  As shown in FIG. 1, an oil supply hole 11b passes through the upper end of the motor case 11, and oil CL as cooling oil is injected into the motor housing HU from the oil supply hole 11b, and into the motor housing HU. Stored (shown in FIG. 4). A sealing plug 11c is screwed into the oil supply hole 11b to shut off the motor housing HU from the outside. The oil CL in the motor housing HU is supplied to the clutch device 2 by a hydraulic pump (not shown), and is also used as hydraulic oil for separating the clutch inner 21 and the clutch outer 22.

  A stator 13 of the electric motor 1 is attached to the inner peripheral portion of the motor case 11 with a screw 13f. The stator 13 is formed by press-fitting a plurality of cores 13 b (corresponding to a stator core) on the inner peripheral surface of a stator ring 13 a fixed to the motor case 11. A coil 13d for generating a rotating magnetic field is wound around each core 13b via an insulator 13c. The plurality of coils 13d arranged circumferentially are respectively connected to an inverter (not shown) of the vehicle via a bus ring 13e. The inverter connects each coil 13d to a vehicle battery (not shown).

  Further, a rotor 14 of the electric motor 1 is disposed inward in the radial direction of the stator 13. The rotor 14 is provided to face the stator 13 while maintaining a predetermined gap. The rotor 14 includes a rotor core 14a formed by laminating a plurality of laminated steel plates 14a1 (corresponding to core plates) in the rotation axis direction. In the rotor core 14a, a first holding plate 14b and a second holding plate 14c (each corresponding to an end plate) are arranged on both end faces in the stacking direction. Hereinafter, the first holding plate 14b and the second holding plate 14c are collectively referred to as holding plates 14b and 14c. The rotor core 14a is clamped by the holding plates 14b and 14c by caulking the end portions of the fastening pins 14d penetrating the rotor core 14a and the holding plates 14b and 14c with the holding plates 14b and 14c in contact with the rotor core 14a. Is done.

  The inner peripheral end of the second holding plate 14c extends radially inward compared to the inner peripheral end of the first holding plate 14b, and a connection hole 14c2 is formed in the inner peripheral edge of the second holding plate 14c. Has been. A connecting bolt 23 is inserted into the connecting hole 14c2, and the second holding plate 14c and the clutch outer 22 are connected by tightening the connecting bolt 23 to the clutch outer 22 described above. Thereby, the rotor 14 is rotatably attached to the motor case 11. Further, as shown in FIG. 1, the rotor 14 has a plurality of field pole magnets 14e arranged on the circumference.

  A plurality of first oil catchers 14b1 and second oil catchers 14c1 (corresponding to oil scooping portions) project in the direction of the rotation axis on the end surfaces of the respective holding plates 14b, 14c that are not in contact with the rotor core 14a. ing. Hereinafter, the first oil catcher 14b1 and the second oil catcher 14c1 are collectively referred to as oil catchers 14b1 and 14c1. Note that a plurality of second oil catchers 14c1, connection holes 14c2, and fastening pins 14d are formed on the circumference, but in FIG. 2 to FIG.

  As shown in FIGS. 2 and 3, the plurality of second oil catchers 14c1 are equally arranged on the second holding plate 14c so as to avoid the fastening pins 14d and the connection holes 14c2. . Each second oil catcher 14c1 extends linearly in the radial direction from the vicinity of the inner peripheral end of the second holding plate 14c to the vicinity of the outer peripheral end. Similarly to the second oil catcher 14c1, the first oil catcher 14b1 also extends linearly in the radial direction from the vicinity of the inner peripheral end to the vicinity of the outer peripheral end on the first holding plate 14b. Therefore, the second oil catcher 14c1 is formed longer in the radial direction than the first oil catcher 14b1.

All of the oil catchers 14b1 and 14c1 have a substantially L shape in which a cross-sectional shape perpendicular to the length direction faces the same direction. As a result, when the rotor 14 rotates, the oil catchers 14b1 and 14c1 can hold the oil CL in the motor housing HU and repel in the rotational direction of the rotor 14. The oil CL repelled by the oil catchers 14b1 and 14c1 is supplied to the stator 13 exposed from the oil surface of the oil CL by the centrifugal force to cool the coil 13d.
In this embodiment, the oil catchers 14b1 and 14c1 are formed by pressing the holding plates 14b and 14c in the thickness direction. However, the method of forming the oil catchers 14b1 and 14c1 is not limited to this, and the oil catchers 14b1 and 14c1 may be formed by a forging method or a method of cutting the end surfaces of the holding plates 14b and 14c.

  In the electric motor 1 having the above-described configuration, for example, a three-phase alternating current is supplied to the coil 13d from the vehicle battery via the inverter. Thereby, a rotating magnetic field is generated in the stator 13, and the rotor 14 is rotated with respect to the stator 13 by an attractive force or a repulsive force caused by the rotating magnetic field. Moreover, the electric power generated by the electric motor 1 is charged into the vehicle battery via the inverter.

  As shown in FIG. 1, an oil guide 12 b (corresponding to a repellent portion) is integrally formed on the inner peripheral surface of the motor cover 12. The oil guide 12 b protrudes rearward in the rotation axis direction from the inner peripheral surface of the motor cover 12 toward the end surface of the rotor 14. As shown in FIG. 4, the oil guide 12 b is formed in an arc shape with the rotation axis as the center, and the lower part is open. As a result, when the rotor 14 rotates and the first oil catcher 14b1 repels the oil CL, even if the oil CL scatters outward (to the left in FIG. 1) in the rotation axis direction, the oil guide 12b repels it. It is. The rebounded oil CL is directly supplied to the coil 13d of the stator 13 or held by the first oil catcher 14b1, and then rebounded toward the coil 13d again.

  According to the present embodiment, in the holding plates 14b and 14c, the oil catchers 14b1 and 14c1 that protrude in the direction of the rotation axis and can repel the oil CL by the rotation of the rotor 14 are provided on the end surfaces of the holding plates 14b and 14c that are not in contact with the rotor core 14a. When the rotor 14 is driven by being formed to extend in the radial direction, the oil CL stored in the motor housing HU is repelled by the oil catchers 14b1 and 14c1. The repelled oil CL scatters radially outward due to centrifugal force and is supplied to the stator 13 exposed on the oil CL in the motor housing HU, so that the stator 13 is efficiently cooled by the oil CL. be able to. Therefore, only by making the oil catchers 14b1 and 14c1 project on the holding plates 14b and 14c, it is not necessary to process each member in a complicated manner, and the electric motor 1 can be easily manufactured.

In particular, the electric motor 1 often has a space in the rotational axis direction as compared to the radial direction of the rotor 14, and the oil catcher 14b1 is formed on the end surfaces of the holding plates 14b and 14c without increasing the size of the electric motor 1. , 14c1 can be easily formed.
In addition, according to the electric motor 1 according to the present embodiment, a pump, piping and the like for cooling the stator 13 are unnecessary, and the electric motor 1 can be made small and low in cost.
Further, since the oil catchers 14b1 and 14c1 are formed by pressing the holding plates 14b and 14c in the thickness direction, the oil catchers 14b1 and 14c1 are formed on the holding plates 14b and 14c in a short time in the manufacturing process. Can do.

  Further, an oil guide 12b is formed on the inner peripheral surface of the motor cover 12 so as to have an arc shape around the rotation axis and project in the direction of the rotation axis toward the end surface of the rotor 14, whereby the first oil catcher 14b1 is formed. The oil CL splashed up and scattered in the direction of the motor cover 12 is repelled on the first holding plate 14b by the oil guide 12b. Accordingly, since the repelled oil CL is repelled again by the first oil catcher 14b1 and supplied to the stator 13, the cooling performance of the stator 13 can be further improved.

<Embodiment 2>
Next, the rotor 14A according to the second embodiment will be described with reference to FIG. In the rotor 14A according to the present embodiment, a plurality of radiation grooves 14b2 and 14c3 are formed on end surfaces of the holding plates 14b and 14c that are not in contact with the rotor core 14a. The radial grooves 14b2 and 14c3 are equally arranged on the holding plates 14b and 14c, respectively, and extend linearly in the radial direction. As a result, on each holding plate 14b, 14c, the first oil catcher 14b3 and the second oil catcher 14c4 (corresponding to the oil scavengers) protruding in the direction of the rotation axis, hereinafter collectively referred to as oil catchers 14b3, 14c4. ) Is formed between the radiation grooves 14b2 and 14c3. The radial grooves 14b2 and 14c3 are formed on the holding plates 14b and 14c by pressing, forging, or cutting. A plurality of radiation grooves 14b2 and 14c3 and oil catchers 14b3 and 14c4 are formed on the circumference, but only one is denoted by a reference numeral in FIG.

  Similar to the oil catchers 14b1 and 14c1 according to the first embodiment, the oil catchers 14b3 and 14c4 according to the present embodiment hold the oil CL by the rotation of the rotor 14A and repel it in the rotation direction of the rotor 14A. Since the other configuration and function of the rotor 14A according to the present embodiment are the same as those of the rotor 14 according to the first embodiment, further description thereof is omitted.

<Embodiment 3>
Next, the rotor 14B according to the third embodiment will be described with reference to FIG. In the rotor 14B according to the present embodiment, a plurality of oil catchers 14c5 (only those formed on the second holding plate 14c in FIG. 6 are shown on the holding plates 14b and 14c, but on the first holding plate 14b. (The same is formed), but protrudes outward in the rotational axis direction. Similar to the oil catchers 14b1 and 14c1 according to the first embodiment, the oil catchers 14c5 (corresponding to the oil lifting unit) are equally arranged circumferentially so as to avoid the fastening pins 14d and the connection holes 14c2. Although a plurality of oil catchers 14c5 are formed on the circumference, only one is denoted by a reference numeral in FIG.

  Each of the oil catchers 14c5 extends in the radial direction of the holding plate 14c, and a cross-sectional shape perpendicular to the length direction thereof is substantially L-shaped. The oil catcher 14c5 draws a curve so as to move in the rotation direction of the rotor 14B (indicated by an arrow on the outer peripheral side of the second holding plate 14c in FIG. 6) as it goes outward in the radial direction of the rotor 14B. Is curved. Since the other configuration and function of the rotor 14B according to the present embodiment are the same as those of the rotor 14 according to the first embodiment, further description thereof is omitted.

  According to the present embodiment, the oil catcher 14c5 is formed in a curved line so as to move in the rotation direction of the rotor 14B as it goes outward in the radial direction. 14c5 easily scoops up and holds the oil CL. Therefore, the oil catcher 14c5 can easily repel the oil CL stored in the lower portion of the motor housing HU, and the cooling performance of the stator 13 by the oil CL can be further improved.

<Embodiment 4>
Next, the rotor 14D according to the fourth embodiment will be described with reference to FIG. In the rotor 14D according to the present embodiment, similarly to the rotor 14 according to the first embodiment, a plurality of oil catchers 14c6 (only those formed on the second holding plate 14c in FIG. 7 are shown on the holding plates 14b and 14c. However, the same is formed on the first holding plate 14b), but protrudes outward in the rotation axis direction. Although a plurality of oil catchers 14c6 are formed on the circumference, only one is denoted by a reference numeral in FIG.

  Each of the oil catchers 14c6 extends in the radial direction of the holding plate 14c, and a cross-sectional shape perpendicular to the length direction is substantially L-shaped. As shown in FIG. 7, the oil catcher 14c6 is formed only radially outward on the rotor 14D. Similar to the oil catchers 14b1 and 14c1 according to the first embodiment, the rotation of the rotor 14D allows the oil catcher 14c6 to hold the oil CL without hindrance and repel it in the rotation direction of the rotor 14D. Since the other configuration and function of the rotor 14D according to the present embodiment are the same as those of the rotor 14 according to the first embodiment, further description thereof is omitted.

<Other embodiments>
The present invention is not limited to the above-described embodiments, and can be modified or expanded as follows.
The oil catchers 14b1 and 14c1 described above may be formed only on one holding plate 14b and 14c.
The oil guide 12 b may be formed on the inner peripheral surface of both the motor cover 12 and the motor case 11 toward the end surface of the rotor 14, or may be formed only on the inner peripheral surface of the motor case 11.

Further, the oil guide 12 b may protrude from the inner peripheral surface of the motor cover 12 or the motor case 11 toward the end surface of the stator 13 in the rotation axis direction. That is, the oil guide 12b may be provided radially outward on the motor cover 12 or the motor case 11 as compared with that shown in FIG.
The electric motor 1 according to the present invention is applicable to a synchronous motor, an induction motor, a DC motor, or any other rotating electric machine.
Moreover, the electric motor 1 according to the present invention may be used only as an electric motor or only as a generator.

  In the drawings, 1 is an electric motor (rotary electric machine), 12b is an oil guide (repelling part), 13 is a stator, 13b is a core (stator core), 13d is a coil, 14, 14A, 14B and 14D are rotors, and 14a is a rotor core. , 14a1 is a laminated steel plate (core plate), 14b is a first holding plate (end plate), 14b1 and 14b3 are first oil catchers (raising portions), 14c is a second holding plate (end plate), and 14c1 and 14c4 are The second oil catcher (raising part), 14c5 and 14c6 are oil catchers (raising part), and HU is a motor housing (housing).

Claims (4)

A housing in which cooling oil is stored;
A stator fixed to the housing and wound around the stator core so that a plurality of coils are arranged on a circumference;
A rotor rotatably mounted within the housing and facing radially inward relative to the stator;
With
The rotor is
A rotor core formed by laminating a plurality of core plates in the rotation axis direction;
A pair of end plates that sandwich both end surfaces of the rotor core in the stacking direction;
It has
In at least one of the end plates, an end surface of the end plate that is not in contact with the rotor core protrudes in the direction of the rotation axis, and an oil lifting portion that can repel the cooling oil by rotation of the rotor extends in the radial direction. Rotating electric machine formed like this.   2. The rotating electrical machine according to claim 1, wherein the oil lifting unit is formed in a curved line so as to move in the rotation direction of the rotor as it goes radially outward.   3. The rotating electrical machine according to claim 1, wherein the oil scraping portion is formed by pressing the end plate in a thickness direction.   4. The repellent portion having an arcuate shape around the rotation shaft and projecting in the direction of the rotation shaft toward the end surface of the rotor or the stator is formed on the inner peripheral surface of the housing. The rotary electric machine as described in any one of them.

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