JP2020129893A - Dynamo-electric motor, vehicle power device having the dynamo-electric motor, dynamo-electric generator, and bearing for wheel with the dynamo-electric generator - Google Patents

Abstract

To provide a dynamo-electric motor that can suppress reduction in output while having a stator of a desired axial length, and can reduce assembly man hours and manufacturing costs, a vehicle power device having the dynamo-electric motor, a dynamo-electric generator, and a bearing for a wheel with the dynamo-electric generator.SOLUTION: A stator core 18a comprises: a circular component 21 formed from a lamination of a plurality of circular plate-like bodies 20, each having a plurality of first radial teeth plate parts 20a and a circular plate part 20b to which a base end part of each first teeth plate part 20a is connected; and a plurality of non-circular components 31 formed from a lamination of a plurality of partial plate-like bodies 22, each containing two second teeth plate parts 22a and 22a which are adjacent to each other in a circumferential direction and a coupling plate part 22b to which the base end parts of the second teeth plate parts 22a and 22a are coupled. The plurality of non-circular components 31 are annularly arranged side by side in the circumferential direction with respect to the circular component 21 so that each first teeth plate part 20a and each second teeth plate part 22a are of the same phase.SELECTED DRAWING: Figure 5

Description

The present invention relates to an electric motor installed in an automobile or the like, a power unit for a vehicle including the electric motor, a generator, and a wheel bearing with a generator including the generator.

With respect to in-vehicle motors, which are in increasing demand with the electrification of automobiles, many efforts have been made to facilitate connection of motor winding coils, save space, and reduce costs. For example, in Patent Documents 1 and 2, a bus bar is installed on an end surface of a motor stator to facilitate coil connection and save space.

However, an in-wheel motor that incorporates a motor inside the wheel, in particular, a running motor with a power generation function that can be stored in the wheel by replacing the existing wheel bearing without modifying the components around the wheel, as in Patent Document 3 In the vehicle power unit equipped with the motor, the space available for housing the motor is small, so that the axial length of the motor is limited, and it is difficult to house the motor even with this bus bar structure.

A general radial three-phase permanent magnet synchronous motor (hereinafter referred to as “BLDC motor”) has a stator structure in which teeth are equally arranged on an annular member. A coil is wound around the tooth, and the coil is configured by connecting a three-phase power line with a bus bar at the axial end of the motor (for example, Patent Documents 4 and 5).
Further, in a BLDC motor, if the number of magnetic poles of the rotor is N and the number of grooves between teeth in the stator is P, there is a fractional groove motor for a motor in which 2N/3P is not an integer (Patent Document 6).

JP, 2010-226832, A JP, 2014-138499, A Japanese Patent Application 2016-184295 Patent No. 5847543 Japanese Patent No. 6139723 JP, 2003-250254, A

A vehicle power plant equipped with a drive-assist motor with a power generation function has the advantage that it can be housed in the wheel and the components around the wheel can be used as is, but the motor output is large because the size of the motor is limited. It is not possible to assist the driving force and efficiently collect electric power during braking. In order to increase the motor output, it is necessary to extend the length of the motor stator core in the wheel axis direction and increase the motor magnetic pole area. However, the motor stator (motor stator core and coil ends) must be installed in a limited space. It becomes difficult to store.

Since the BLDC motor having the radial structure has a structure in which a winding is wound around a stator, a portion where the coil turns are overlapped with the axial end portion of the stator, and this portion is called a coil end. Further, in order to connect the coils, a coil connecting portion is formed in the motor axial direction. Due to the region formed by these coils, the axial dimension of the motor requires the axial dimension in addition to the opposing portions of the rotor core and the stator core that generate the motor torque. There is a method to reduce the dimension of the coil connection part by using a bus bar for the coil end connection of the motor winding coil, but the conventional method of installing the bus bar on the end surface of the coil end is the entire length of the motor stator, that is, the wheel of the motor stator. There is a limit to shortening the axial length.

The axial dimension of the motor core (the motor facing dimension) is proportional to the motor output, and this can be achieved by increasing the axial dimension of the motor core as a method of obtaining a large output. As shown in FIG. 16, the axial dimension of the radial motor is determined by the sum of the motor core dimension (1), the coil end dimension (2), and the coil connection portion dimension (3). In the case where the axial dimension for incorporating the motor is determined, if the place where the coil connecting portion is installed is set in the axial direction, the motor core width must be reduced, and the motor output is reduced.

The stator in a general motor is an annular structure that is uniform in the axial direction. The winding start and winding end of each stator coil cannot be taken out in the middle of the motor axial direction, and are located at the axial end of the stator core. For this reason, in the conventional motor, the coil connection portion is generally configured at the axial end portion of the motor.

Therefore, the applicant of the present application, as an electric motor capable of increasing the output without increasing the axial length of the stator, has a structure in which the stator core is divided in the circumferential direction, and the stator coil is arranged within the axial width of the stator core. A technique provided with a connection part is proposed (Japanese Patent Application No. 2018-97560).
However, in this technique, since the bridge portion and the teeth portion of the stator are separated from each other and there is no annular portion, it is possible that the teeth cannot be evenly arranged due to the processing accuracy or the assembly accuracy of the bridge portion. .. The fractional groove motor disperses the torque all over the circumference to generate a low cogging torque and a low torque ripple, but the positional deviation of the teeth assembly causes an excessive cogging torque or a torque ripple. Moreover, the number of assembly steps and the manufacturing cost of the stator fixing member are increased.

An object of the present invention is to provide an electric motor capable of suppressing a reduction in output with the stator having a desired axial length and reducing the number of assembly steps and manufacturing cost, and a vehicle power unit equipped with this electric motor. An object of the present invention is to provide a generator and a bearing for wheels with a generator including the generator.

An electric motor according to the present invention is an electric motor that includes a stator having a stator core and a stator coil wound around the stator core, and a rotor positioned to face the stator in a radial direction.
The stator core is
A ring-shaped component in which a plurality of ring-shaped plate-shaped bodies having a plurality of first tooth plate parts radially provided and a ring-shaped plate part to which the base end parts of these first tooth plate parts are connected are stacked,
A plurality of non-circular layers in which a plurality of partial plate-shaped bodies including at least two second tooth plate portions adjacent to each other in the circumferential direction and a connecting plate portion to which the base end portions of these second tooth plate portions are connected are stacked. And a ring part,
The plurality of tooth plates of the first annular plate member and the second tooth plates of the second partial plate member are in phase with each other so that the plurality of tooth plates are arranged in the same phase. The non-annular components are arranged in a circle in a circumferential direction.

According to this configuration, since a plurality of non-circular ring components are arranged in a ring shape in the circumferential direction with respect to the circular ring component, a space is formed on the inner diameter side or the outer diameter side of the stator core, and the axial width of the stator core is reduced. It becomes easy to provide the connection area of the stator coil in the. Therefore, it is possible to suppress the reduction of the electric motor output by setting the stator core to a desired axial length. In addition, since the stator core has a plurality of non-annular parts arranged in an annular shape in the circumferential direction with respect to the annular part, the manufactured stator can be handled as an integrated structure, and the maneuverability and assemblability are good. The dimensional accuracy of the stator as the motor assembly is better than that of a stator structure in which the stator core is simply divided in the circumferential direction. Therefore, the number of assembly steps and the manufacturing cost can be reduced.

The non-circular ring components that are adjacent to each other in any of the circumferential directions may be arranged so that a wiring gap is formed between them. In this case, by passing the stator coil through the gap between the non-ring parts adjacent to each other in the circumferential direction, the coil connection on the inner diameter side of the stator core is facilitated.

A vehicle power unit of the present invention has a fixed wheel and a rotating wheel rotatably supported by the fixed wheel via rolling elements, and a wheel of a vehicle is attached to a hub flange provided on the rotating wheel. Bearings and the electric motor according to any one of the inventions mounted on the wheel bearing, the stator is mounted on the fixed ring, and the rotor is mounted on the rotating wheel.

According to this configuration, by mounting the electric motor capable of making the stator core a desired axial length on the wheel bearing, the overall length of the vehicle power unit is shortened. As a result, the vehicle power unit can be replaced with the existing wheel bearing without modifying the undercarriage frame parts to the components around the wheels.

In the electric motor, teeth are formed by a plurality of teeth plate portions that overlap each other in the same phase, and the electric motor has N as the number of magnetic poles of the rotor and P as the number of grooves between teeth that are circumferentially adjacent to each other in the stator. In that case, a three-phase permanent magnet synchronous motor in which 2N/3P is not an integer may be used.
P and N are arbitrary natural numbers.
In this case, since a so-called fractional groove three-phase permanent magnet synchronous motor in which 2N/3P is not an integer is adopted, cogging torque can be reduced and torque density can be improved. Since the torque density can be improved, the motor output can be increased. The ratio of P and N is, for example, P:N=4:5.

The electric motor may be an outer rotor type in which the rotor is located radially outward of the stator, and the wire connecting portion of the stator coil is arranged radially inward of the stator core. In this case, the diameter of the radially extending teeth tip surface of the outer rotor side motor is larger than that of the inner rotor type motor of the same size, so the rotor and stator face each other more than the inner rotor type motor of the same size. The area to be used can be increased. This makes it possible to maximize the output torque in a limited space.

The non-annular component may be sandwiched and disposed between two annular components that are axially spaced apart. In this case, since the through hole can be provided in the central portion in the axial direction of the stator, the stator coil can be passed through the through hole to facilitate the connection of the stator coil.

Each of the first and second teeth plate portions may extend straight from the base end portion to the tip end portion, or may be provided with ribs protruding from the tip end portion in an arc shape on both sides in the circumferential direction.
When each of the first and second tooth plate portions extends straight from the base end portion to the tip end portion, winding on the stator core is facilitated, and the assemblability is improved.
When each of the first and second teeth plate portions is provided with ribs projecting from the tip portion to both sides in the circumferential direction in an arc shape, the flow of the magnetic flux is optimized, the output of the electric motor can be improved, and the cogging torque can be improved. Can be reduced. In addition, the ribs are provided at the tip portions of the first and second tooth plate portions, so that the stator coil does not easily come off.

A generator according to the present invention is a generator including a stator having a stator core and a stator coil wound around the stator core, and a rotor positioned to face the stator in a radial direction,
The stator core is
A ring-shaped component in which a plurality of ring-shaped plate-shaped bodies having a plurality of first tooth plate parts radially provided and a ring-shaped plate part to which the base end parts of these first tooth plate parts are connected are stacked,
A plurality of non-circular layers in which a plurality of partial plate-shaped bodies including at least two second tooth plate portions adjacent to each other in the circumferential direction and a connecting plate portion to which the base end portions of these second tooth plate portions are connected are stacked. And a ring part,
The plurality of tooth plates of the first annular plate member and the second tooth plates of the second partial plate member are in phase with each other so that the plurality of tooth plates are arranged in the same phase. The non-annular components are arranged in a circle in a circumferential direction.

According to this configuration, since a plurality of non-circular ring components are arranged in a ring shape in the circumferential direction with respect to the circular ring component, a space is formed on the inner diameter side or the outer diameter side of the stator core, and the axial width of the stator core is reduced. In addition, it becomes easy to configure the connection area of the stator coil. Therefore, it is possible to suppress the reduction of the generator output by setting the stator core to a desired axial length. In addition, since the stator core has a plurality of non-annular components arranged in a circle in the circumferential direction with respect to the circular component, the manufactured stator can be handled as an integrated structure, and is easy to handle and assemble. The dimensional accuracy of the stator as the generator assembly is better than that of a stator structure in which the stator core is simply divided in the circumferential direction. Therefore, the number of assembly steps and the manufacturing cost can be reduced.

The bearing device for a wheel with a generator of the present invention has a fixed wheel and a rotating wheel rotatably supported on the fixed wheel via rolling elements, and a vehicle wheel is mounted on a hub flange provided on the rotating wheel. A bearing for a wheel to be mounted, and the generator according to the invention mounted on the bearing for the wheel, the stator being mounted on the fixed wheel, and the rotor being mounted on the rotating wheel. ..

According to this structure, the total length of the generator-equipped wheel bearing device is shortened by mounting the generator capable of making the stator core a desired axial length on the wheel bearing. As a result, it becomes possible to replace the bearing device for a wheel with a generator with the existing bearing for a wheel without modifying the undercarriage frame component to the components around the wheel.

An electric motor according to the present invention is an electric motor that includes a stator having a stator core and a stator coil wound around the stator core, and a rotor positioned to face the stator in a radial direction. An annular component in which a plurality of annular plate-shaped bodies having a plurality of first tooth plate portions provided and an annular plate portion to which the base end portions of these first tooth plate portions are connected are laminated, and in the circumferential direction. A plurality of non-annular components in which a plurality of partial plate-shaped bodies including at least two adjacent second tooth plate portions and a connecting plate portion in which the base end portions of these second tooth plate portions are connected are stacked; And, so that the first tooth plate portion of the annular plate member and the second tooth plate portion of the partial plate member have the same phase, with respect to the annular component, Since the plurality of non-circular ring components are arranged in a circle in the circumferential direction, it is possible to suppress the reduction in output with the stator having a desired axial length and to reduce the number of assembly steps and the manufacturing cost. You can

A vehicle power unit of the present invention has a fixed wheel and a rotating wheel rotatably supported by the fixed wheel via rolling elements, and a wheel of a vehicle is attached to a hub flange provided on the rotating wheel. A bearing is provided for the wheel, and the electric motor according to any one of the above-described aspects is mounted on the bearing for the wheel. The stator is attached to the fixed ring and the rotor is attached to the rotating wheel. It is possible to suppress the reduction of the output as the axial length of, and it is possible to reduce the number of assembly steps and the manufacturing cost.

A generator according to the present invention is a generator including a stator having a stator core and a stator coil wound around the stator core, and a rotor positioned to face the stator in a radial direction, and the stator core includes: A circular ring component in which a plurality of circular plate members having a plurality of first tooth plate portions radially provided and a circular ring plate portion to which the base end portions of these first tooth plate portions are connected are laminated, and a circular circumference. A plurality of non-annular components in which a plurality of partial plate-shaped bodies including at least two second teeth plate portions adjacent to each other in the direction and a connection plate portion in which the base end portions of these second teeth plate portions are connected are stacked. And in the annular component such that the first tooth plates of the annular plate and the second tooth plates of the partial plate have the same phase. On the other hand, since the plurality of non-annular components are arranged side by side in the circumferential direction in an annular shape, it is possible to suppress the output reduction by setting the stator to a desired axial length and reduce the assembly man-hour and the manufacturing cost. Can be planned.

The bearing device for a wheel with a generator of the present invention has a fixed wheel and a rotating wheel rotatably supported on the fixed wheel via rolling elements, and a vehicle wheel is mounted on a hub flange provided on the rotating wheel. A wheel bearing to be mounted, and the generator according to the invention described above mounted to the wheel bearing, wherein the stator is mounted on the fixed wheel and the rotor is mounted on the rotating wheel. It is possible to suppress a reduction in output as a desired axial length, and it is possible to reduce the number of assembly steps and the manufacturing cost.

FIG. 1 is a sectional view of a vehicle power unit according to an embodiment of the present invention. It is the II-II sectional view taken on the line of FIG. FIG. 3 is a perspective view of an electric motor of the vehicle power unit. FIG. 4 is a sectional view taken along line IV-IV in FIG. 2. FIG. 3 is a perspective view showing a stator core, an annular plate member and a partial plate member of the electric motor. It is the front view which changed the same partial plate-shaped body and this partial plate-shaped body. It is a sectional view showing a T-shaped rotor composition example. It is a perspective view of the stator core of the electric motor which concerns on other embodiment of this invention. It is an exploded perspective view of the stator core. It is a sectional view of a power unit for vehicles provided with the electric motor. It is the XI-XI sectional view taken on the line of FIG. FIG. 9 is a perspective view showing a stator core, an annular plate member and a partial plate member of an electric motor according to still another embodiment of the present invention. FIG. 2 is a block diagram showing a conceptual configuration of a vehicle system of a vehicle including any of the vehicle power units. FIG. 3 is a power supply system diagram showing an example of a vehicle equipped with the vehicle system. It is a figure explaining the notional composition of the system for vehicles of other vehicles provided with the power unit for vehicles. It is sectional drawing of the conventional inner rotor type motor.

[First Embodiment]
A vehicle power unit according to an embodiment of the present invention will be described with reference to FIGS. 1 to 6.
As shown in FIG. 1, the vehicle power unit 1 includes a wheel bearing 2 and an electric motor 3 that is a generator that also serves as an electric motor. In the case of a generator that does not also serve as an electric motor, the generator-equipped wheel bearing device includes the generator 3 that does not also serve as an electric motor and the wheel bearing 2.

<Wheel bearing 2>
The wheel bearing 2 has an outer ring 4 which is a fixed wheel, a double row rolling element 6, and an inner ring 5 which is a rotating wheel. The bearing space between the outer ring 4 and the inner ring 5 is filled with grease. A vehicle body mounting flange 4a is provided on the outer peripheral surface of the outer ring 4 on the inboard side so as to project radially outward. The vehicle body mounting flange 4a is fixed to the knuckle 8 which is a suspension frame component.
The inner ring 5 has a hub ring 5a and a partial inner ring 5b fitted to the outer peripheral surface of the hub ring 5a on the inboard side. The hub wheel 5a has a hub flange 7 at a location that projects more toward the outboard side in the axial direction than the outer wheel 4.

A brake rotor 12 and a wheel rim (not shown) are attached to a side surface of the hub flange 7 on the outboard side by a hub bolt 13 in a state where the brake rotor 12 and a rim of a wheel (not shown) are axially overlapped. A tire (not shown) is attached to the outer periphery of the rim.
In this specification, the side closer to the outer side in the vehicle width direction of the vehicle when the vehicle power unit 1 is mounted on the vehicle is called the outboard side, and the side closer to the center in the vehicle width direction of the vehicle is the inboard side. Call it the board side.

<About brake 17>
The brake 17 is a friction brake including a disc-shaped brake rotor 12 and a brake caliper 16 (FIG. 13). The brake rotor 12 has a flat plate portion 12a and an outer peripheral portion 12b. The flat plate portion 12 a is an annular flat plate member that overlaps the hub flange 7. The outer peripheral portion 12b includes a cylindrical portion 12ba that extends cylindrically from the outer peripheral edge of the flat plate portion 12a toward the inboard side, and a flat plate portion 12bb that extends outward from the inboard side end of the cylindrical portion 12ba toward the outer diameter side. Have and.
The brake caliper 16 (FIG. 13) is attached to the knuckle 8 which is a suspension frame component in a vehicle, and has a friction pad (not shown) that sandwiches the flat plate portion 12bb. The brake caliper 16 (FIG. 13) may be either a hydraulic type or a mechanical type, and may be an electric motor type.

<About electric motor 3>
The electric motor 3 of this example is a motor-generator for traveling assistance that generates electric power by rotation of wheels and is capable of rotationally driving the wheels by power supply. The electric motor 3 includes a stator 18 and a rotor 19 that is positioned to face the stator 18 in the radial direction.
As shown in FIGS. 2 and 3, in this electric motor 3, the number of magnetic poles of the rotor 19 is N (N=5 in this example), and the number of grooves between the teeth Ts adjacent to each other in the circumferential direction in the stator 18 is set. When P (P=4 in this example), 2N/3P is a fractional groove three-phase permanent magnet synchronous motor (fractional groove BLDC motor) which is not an integer.

In the winding structure of the electric motor 3 which is the fractional groove BLDC motor, the stator coils 18b of the respective phases are wound around each tooth Ts by concentrated winding. A single-layer winding structure in which the stator coil 18b is wound every other tooth Ts (FIG. 7 described later) may be used.
As shown in FIG. 1, the electric motor 3 is an outer rotor type in which a rotor 19 is located radially outside the stator 18. Further, the electric motor 3 is of a direct drive type in which the rotor 19 is attached to the inner ring 5 which is the rotating wheel of the wheel bearing 2.

The electric motor 3 is installed radially inward of the inner diameter 12c of the brake rotor 12, and is installed in the axial range L1 between the hub flange 7 and the outboard side surface 8a of the knuckle 8. The electric motor 3 is, for example, a surface magnet type permanent magnet motor of an outer rotor type, that is, an SPM (Surface Permanent Magnet) synchronous motor (or noted as SPMSM (Surface Permanent Magnet Synchronous Motor)). The electric motor 3 may be an IPM (Interior Permanent Magnet) synchronous motor (or an IPMSM (Interior Permanent Magnet Synchronous Motor)). The electric motor 3 may be a switched reluctance motor.

As shown in FIGS. 1 and 2, the rotor 19 includes a cylindrical rotating case 15 attached to the outer peripheral edge of the hub flange 7, and a plurality of permanent magnets 14 provided on the inner peripheral surface of the rotating case 15. Equipped with. The rotating case 15 is made of, for example, a soft magnetic material and has a cylindrical shape concentric with the inner ring 5. The rotating case 15 may be manufactured by cutting or casting as an integral metal part, or after being manufactured with a plurality of divided structures, the divided structures are fixed by, for example, welding, bonding, or the like. Good. A plurality of recesses are formed on the inner peripheral surface of the rotating case 15 at regular intervals in the circumferential direction, and the permanent magnets 14 are fitted in the recesses and fixed by adhesion or the like.

<Torus parts and non-torus parts>
The stator 18 has a stator core 18a and a stator coil 18b wound around the stator core 18a.
As shown in FIG. 5(a), the stator core 18a includes an annular component 21 in which a plurality of annular plate members 20 (FIG. 5(b)) are laminated concentrically with the outer ring 4 (FIG. 1), and a partial plate. A plurality of non-circular ring components 31 in which a plurality of sheets 22 (FIG. 5C) are laminated are provided.

As shown in FIG. 5B, the annular plate member 20 includes a plurality of (12 in this example) first teeth plate portions 20a radially provided and base ends of the first teeth plate portions 20a. It has an annular plate portion 20b to which the parts are connected. The annular plate member 20 is made of, for example, an electromagnetic steel plate. As shown in FIG. 5C, in the partial plate-shaped body 22, the two second teeth plate portions 22a adjacent to each other in the circumferential direction and the base end portions of these second teeth plate portions 22a, 22a are arcuate. It is configured in a U-shape including the connecting plate portion 22b connected to. The partial plate-shaped body 22 is made of, for example, an electromagnetic steel plate. As shown in FIG. 5A, the teeth Ts are configured by the plurality of first and second tooth plate portions 20a and 22a overlapping in the same phase.

As shown in FIGS. 5(b), 5(c) and 6(a), the first and second tooth plate portions 20a, 22a extend straight from the base end portion to the tip end portion. In other words, the tip portions of the first and second tooth plate portions 20a, 22a are straight without ribs. In this case, winding on the stator core 18a (FIG. 5A) becomes easy, and the assembling property is improved.

As shown in FIG. 5A, in the stator core 18a, the first teeth plate portions 20a of the annular plate body 20 and the second teeth plate portions 22a of the partial plate body 22 have the same phase. As described above, a plurality (six in this example) of non-annular parts 31 are arranged in the annular part 21 side by side in the circumferential direction at equal intervals. The annular plate-shaped body 20 and the partial plate-shaped body 22 are punched by corresponding press dies (not shown), and are laminated by caulking or bonding in a progressive die (not shown). For this reason, the manufactured stator can be handled as an integrated structure, is easy to handle and assemble, and the dimensional accuracy of the stator as the motor assembly is better than that of a stator structure in which the stator core is simply divided in the circumferential direction. Good.

As shown in FIGS. 1 and 4, an annular member 24 is fixed to the outer peripheral surface of the outer ring 4 on the outboard side, and the inner peripheral surface of the annular member 21 in the stator core 18a is fixed to the outer peripheral surface of the annular member 24. It is fixed. The fixing method between the stator core 18a and the annular member 24 may be caulking, bonding, welding or the like.
The annular member 24, which is a stator fixing component, is made of a magnetic material. Therefore, the magnetic flux of the stator 18 passes through the annular member 24, and the output of the electric motor 3 is improved. The annular member 24 may be made of an insulating material. In this case, insulation between the annular member 24 and the peripheral components is ensured, and for example, it is possible to prevent a short-circuit current when the coil is short-circuited from being conducted to the peripheral components.

As shown in FIG. 4 and FIG. 5A, the non-annular components 31, 31 that are adjacent to each other in the circumferential direction are arranged so that a wiring gap δ1 is formed. As shown in FIG. 3 and FIG. 4, the stator coil 18b of each phase of the UVW is connected to each tooth Ts in which the first and second tooth plate portions 20a and 22a are laminated via an insulating material such as a bobbin (not shown). The stator coil 18b can be easily connected on the inner diameter side of the stator by passing the stator coil 18b through the gap δ1 that is wound and the ring is divided into the inner diameter side. Further, it becomes easy to form a space on the inner diameter side of the stator core 18a and form a coil connection area within the width dimension of the electric motor 3.

<About Bus Bar 25>
A bus bar 25 is connected to the connecting portion of the stator coil 18b. Further, a three-core motor wire is connected to the bus bar 25. The bus bar 25, which is a connection component, is provided within the axial width of the stator core 18a and on the inner diameter side of the stator core 18a on the inboard side of the annular member 24. The bus bar 25 of this example includes three bus bars of three phases (U phase, V phase, W phase) and one bus bar of a neutral point, and a coil end portion is provided on a circumference or an end portion of each bus bar 25. 18ba is fixed by welding, caulking, screwing or the like. A total of four bus bars 25 are arranged on the inner diameter side of the stator core 18a at predetermined intervals. Each bus bar 25 is fixed to the annular member 24 via, for example, a pin (not shown) made of an insulating material or an insulating-treated member.

<About the seal structure>
As shown in FIG. 1, between the inner peripheral surface of the rotating case 15 on the inboard side and the outer peripheral surface of the vehicle body mounting flange 4a, water and foreign matter are prevented from entering the inside of the electric motor 3 and the wheel bearing 2. A seal member 23 is arranged.

<About the rotation detector 27>
The vehicle power unit 1 is provided with a rotation detector 27. The rotation detector 27 detects the rotation angle or the rotation speed of the inner ring 5 with respect to the outer ring 4 in order to control the rotation of the electric motor 3 for traveling assistance. The rotation detector 27 has a detected part 27a attached to the detected part holding member and the like, and a sensor part 27b for detecting the detected part 27a. The sensor portion 27b is fixed to the inner peripheral surface of the outer ring 4 on the inboard side via a sensor fixing member 28. A resolver, for example, is applied as the rotation detector 27. It should be noted that the rotation detector 27 is not limited to a resolver, and may be, for example, an encoder, a pulsar ring, a hall sensor, or the like, and may be mounted in one or more or in combination.

<Cover 29 etc.>
At the end of the outer ring 4 on the inboard side, a cylindrical cover 29 that covers the end of the inboard side is attached. The motor wire of the electric motor 3 is supported on the cover 29 via, for example, a panel mount type power line connector (not shown). The cover 29 also supports a sensor connector (not shown), and a wire (not shown) extending from the sensor portion 27b is supported by the sensor connector.

<Effect>
According to the electric motor 3 described above, since the plurality of non-annular components 31 are annularly arranged side by side in the circumferential direction with respect to the annular component 21, a space is formed on the inner diameter side of the stator core 18a and the stator core 18a is It becomes easy to provide the connection area of the stator coil 18b within the axial width. Therefore, the stator core 18a can be made to have a desired axial length to suppress the reduction of the motor output. Since the wiring portion is on the inner diameter side of the stator core 18a, the width of the stator core can be increased and the torque can be increased within the same motor size. Further, since a part of the stator core 18a of the electric motor 3 has a divided shape, the output can be improved more than that of an electric motor having a divided shape.

Further, in the stator core 18a, since the plurality of non-annular components 31 are arranged in a ring shape with respect to the annular component 21, the stator 18 after manufacturing can be handled as an integrated structure, and handling and It is easy to assemble, and the dimensional accuracy of the stator 18 as the motor assembly is better than that of a stator structure in which the stator core is simply divided in the circumferential direction. Therefore, the number of assembly steps and the manufacturing cost can be reduced.

Since the non-annular components 31, 31 that are adjacent to each other in the circumferential direction are arranged so that a gap δ1 for wiring is formed, the gap δ1 between the non-annular components 31 and the non-annular component 31 that are circumferentially adjacent to each other. Through the stator coil 18b, the coil connection on the inner diameter side of the stator core 18a is facilitated.
In the usual electric motor structure, the coil end can be taken out only from the axial end of the stator core. However, according to the stator core 18a of this configuration, the non-ring part 31 and the non-ring part 31 that are circumferentially adjacent to each other are provided. Since there is a gap (notch) δ1 between the two, the coil end portion 18ba can be taken out from the axially intermediate portion of the stator core 18a. By taking out the coil end portion 18ba from the axially intermediate portion of the stator core 18a, the degree of freedom in arranging the stator coil 18b is improved. In the case of configuring the coil connection inside the electric motor in a normal electric motor, the coil needs to pass through the end of the electric motor and be routed inside the electric motor, the bending of the coil increases, insulation failure easily occurs, Manufacturing becomes difficult.

According to the vehicular power plant 1 including the electric motor 3, the total length of the vehicular power plant 1 is shortened by mounting the electric motor 3 capable of making the stator core 18a a desired axial length on the wheel bearing 2. Become. As a result, the vehicle power unit 1 can be replaced with the existing wheel bearing without modifying the knuckle 8 around the components around the wheel.

Since the three-phase permanent magnet synchronous motor having a fractional groove where 2N/3P is not an integer is adopted as the electric motor 3, the cogging torque can be reduced and the torque density can be improved. Since the torque density can be improved, the motor output can be increased. Although the positional deviation of the assembly of the teeth leads to the generation of excessive cogging torque or torque ripple, the stator core structure in which a plurality of non-circular ring components 31 are arranged in a circle in the circumferential direction with respect to the circular ring component 21. By so doing, it is possible to obtain the characteristics of low cogging torque and low torque ripple that are comparable to those obtained when the stator core is manufactured integrally.

Since the electric motor 3 is an outer rotor type in which the rotor 19 is located radially outward of the stator 18, it is possible to increase the area where the rotor 19 and the stator 18 face each other as compared with an inner rotor type electric motor of the same size. This makes it possible to maximize the output torque in a limited space.

<About other embodiments>
In the following description, the parts corresponding to the items previously described in the respective embodiments will be denoted by the same reference symbols, and redundant description will be omitted. When only a part of the configuration is described, the other parts of the configuration are the same as those described above unless otherwise specified. The same function and effect are obtained from the same configuration. Not only the combination of the parts specifically described in each of the embodiments, but also the embodiments may be partially combined with each other as long as the combination does not cause any trouble.

As shown in FIGS. 6B and 7, each of the second and first tooth plate portions 22a and 20a (FIG. 5B) has a rib Rb that protrudes in an arc shape from the tip portion to both sides in the circumferential direction. May be provided. The winding structure of FIG. 7 has a single-layer winding structure in which the stator coil 18b is wound every other tooth Ts. Since the ribs Rb are provided on the second and first teeth plate portions 22a, 20a (FIG. 5(b)), the facing area with the permanent magnet 14 can be increased, and the output of the electric motor 3 can be improved. In addition, the cogging torque can be reduced. Further, since the ribs Rb are provided at the tips of the second and first teeth plate portions 22a and 20a (FIG. 5B), the stator coil 18b has a structure that does not easily come off.

As shown in FIGS. 8 and 9, the first teeth plate portions 20a of the annular plate body 20 and the second teeth plate portions 22a of the partial plate body 22 have the same phase, A plurality (six in this example) of non-annular parts 31 are annularly arranged in a circumferentially equidistant manner between a pair of annular parts 21, 21 arranged at intervals in the axial direction. May be. In the configuration example in which the non-annular component 31 is sandwiched between the pair of annular components 21, 21 such as the stator core 18a, the through hole (gap) 32 can be provided at the central portion in the axial direction of the stator. As shown in FIGS. 10 and 11, the stator coil 18b can be passed through the through hole 32 (FIG. 8) to the inner diameter side of the stator core 18a to facilitate the connection of the stator coil 18b on the inner diameter side of the stator.

Since the stator coil 18b can be passed from the through hole 32 (FIG. 8) to the inner diameter side of the stator core 18a, the stator core 18a is provided with two annular members 24, 24 arranged at a predetermined interval in the axial direction. The stator coil 18b is fixed to the outer ring 4 and the connecting portion of the stator coil 18b is installed between the two annular members 24, 24.
With this structure, the rigidity for supporting the stator 18 is increased, and the vibration and sound generated when the electric motor 3 is driven is less likely to occur.

The partial plate-shaped body 22 is not limited to the U-shape. For example, as shown in FIG. 12C, the partial plate-shaped body 22 has a connecting plate portion 22b in which the base end portions of four second tooth plate portions 22a adjacent in the circumferential direction are connected in an arc shape. It may have a shape that includes it. As shown in FIG. 12( a ), the stator core 18 a includes first tooth plates 20 a of the annular plate body 20 (FIG. 12( b )) and second tooth plates of the partial plate body 22. A plurality (three in this example) of non-annular components 31 are arranged in an annular shape in the circumferential direction so as to be in phase with the plate portion 22a and are arranged in the circumferential direction at equal intervals. According to this configuration, the flow of the magnetic flux is optimized and the output of the electric motor is improved because the length of the connecting plate portion 22b is longer than that of the shape of FIG.

<Vehicle system>
FIG. 13 is a block diagram showing a conceptual configuration of a vehicle system using any one of the vehicle power units 1.
In this vehicle system, the vehicle power unit 1 is mounted on the driven wheel 10 _B in the vehicle 30 having the driven wheel 10 _B that is mechanically uncoupled from the main drive source. The wheel bearing 2 (FIG. 1) in the vehicle power unit 1 is a bearing that supports the driven wheel 10 _B.

The main drive source 35 is an internal combustion engine such as a gasoline engine or a diesel engine, a motor generator (electric motor), or a hybrid drive source in which both are combined. The "motor generator" is referred to as an electric motor capable of generating electric power by imparting rotation. In the illustrated example, the vehicle 30 is a front-wheel drive vehicle in which the front wheels are the drive wheels 10 _A and the rear wheels are the driven wheels 10 _B, and the main drive source 35 is an internal combustion engine 35 a and a drive-wheel-side motor generator 35 b. It is a hybrid car (hereinafter, may be referred to as "HEV") having a.

Specifically, it is a mild hybrid type in which the motor generator 35b on the drive wheel side is driven by a medium voltage such as 48V. Hybrids are roughly classified into strong hybrids and mild hybrids. A mild hybrid is a type in which the main drive source is an internal combustion engine, and a motor mainly assists running when starting or accelerating. In the (electric vehicle) mode, it is distinguished from the strong hybrid because it can not run for a long time even if it can run normally. Internal combustion engine 35a of the example of the figure, is connected to the drive shaft of the drive wheel 10 _A via the clutch 36 and speed reducer 37, the motor generator 35b of the driving wheel is connected to a reduction gear 37.

This vehicle system includes an electric motor 3 which is a drive-assisting motor generator for rotationally driving the driven wheels 10 _B , an individual control means 39 for controlling the electric motor 3, and an individual ECU provided in the host ECU 40. An individual motor/generator command means 45 for outputting a command to cause the means 39 to control driving and regeneration. The electric motor 3 is connected to the power storage means. A battery (storage battery), a capacitor, a capacitor, or the like can be used as the power storage unit, and its type and mounting position on the vehicle 30 are not limited, but in this embodiment, the low-voltage battery 50 mounted on the vehicle 30 and The medium voltage battery 49 is the medium voltage battery 49.

The electric motor 3 for the driven wheels is a direct drive motor that does not use a transmission. The electric motor 3 acts as an electric motor by supplying electric power, and also acts as a generator that converts the kinetic energy of the vehicle 30 into electric power.
In the electric motor 3, since the rotor 19 (FIG. 1) is attached to the inner ring 5 (FIG. 1) that is a hub wheel, when a current is applied to the electric motor 3, the inner ring 5 (FIG. 1) is rotationally driven, and conversely, power regeneration is performed. Regenerative power is sometimes obtained by loading an induced voltage.

<Regarding the control system of the vehicle 30>
The host ECU 40 is a unit that performs integrated control of the vehicle 30, and includes a torque command generation unit 43. The torque command generating means 43 generates a torque command according to signals of operation amounts input from an accelerator operating means 56 such as an accelerator pedal and a brake operating means 57 such as a brake pedal. The vehicle 30 includes a motor generator 35b of the internal combustion engine 35a and the drive wheel as the main drive source 35, and because with the two electric motors 3, 3 for driving two driven wheels ₁₀ B, 10 _B, respectively, wherein The host ECU 40 is provided with a torque command distribution unit 44 that distributes the torque command according to the rules set for the drive sources 35 a, 35 b, 3, 3.

The torque command for the internal combustion engine 35a is transmitted to the internal combustion engine control means 47 and is used by the internal combustion engine control means 47 for valve opening control and the like. The torque command to the drive wheel side generator/motor 35b is transmitted to the drive wheel side motor/generator control means 48 and executed. The torque command to the electric motors 3, 3 on the driven wheel side is transmitted to the individual control means 39, 39. A portion of the torque command distribution means 44 that outputs to the individual control means 39, 39 is referred to as an individual motor/generator command means 45. The individual motor generator commanding means 45 also has a function of giving a torque command to the individual control means 39, which is a command of a braking force for the braking of the electric motor 3 by regenerative braking, in response to the signal of the operation amount of the brake operating means 57. Prepare

The individual control means 39 is an inverter device, and includes an inverter 41 that converts the DC power of the medium voltage battery 49 into a three-phase AC voltage, and a control unit 42 that controls the output of the inverter 41 by PWM control or the like according to the torque command or the like. Have. The inverter 41 includes a bridge circuit (not shown) including semiconductor switching elements and the like, and a charging circuit (not shown) that charges the intermediate voltage battery 49 with the regenerative power of the electric motor 3. The individual control means 39 is provided separately for the two electric motors 3, 3, but may be housed in one housing and the control unit 42 may be shared by both the individual control means 39, 39. ..

FIG. 14 is a power supply system diagram showing an example of a vehicle equipped with the vehicle system shown in FIG. In the example of the figure, a low-voltage battery 50 and a medium-voltage battery 49 are provided as batteries, and both batteries 49, 50 are connected via a DC/DC converter 51. There are two electric motors 3, but only one is shown as a representative. Although not shown in FIG. 14, the motor generator 35b on the drive wheel side in FIG. 13 is connected to the medium power system in parallel with the motor 3 on the driven wheel side. A low voltage load 52 is connected to the low voltage system, and a medium voltage load 53 is connected to the medium voltage system. There are a plurality of low voltage loads 52 and a plurality of medium voltage loads 53, but one is representatively shown.

The low-voltage battery 50 is a battery generally used in various automobiles as a power source for a control system, and is set to, for example, 12V or 24V. The low-voltage load 52 includes basic components such as a starter motor of the internal combustion engine 35a, lights, the host ECU 40, and other ECUs (not shown). The low voltage battery 50 may be referred to as an auxiliary battery for electrical accessories, and the medium voltage battery 49 may be referred to as an auxiliary battery for an electric system.

The medium-voltage battery 49 has a higher voltage than the low-voltage battery 50 and is lower than a high-voltage battery (100 V or more, for example, about 200 to 400 V) used in a strong hybrid vehicle or the like, and an electric shock during work is not affected. A 48V battery, which has a voltage that does not cause a problem and is used for a mild hybrid in recent years, is preferable. The medium voltage battery 49 such as a 48V battery can be relatively easily installed in a vehicle equipped with a conventional internal combustion engine, and can reduce fuel consumption by power assist and regeneration by electric power as a mild hybrid.

The medium voltage load 53 of the 48V system is the accessory component, and is a power assist motor that is the electric motor 3 on the drive wheel side, an electric pump, an electric power steering, a supercharger, an air compressor, or the like. By configuring the load of accessories with a 48V system, the power assist output will be lower than with high voltage (such as strong hybrid vehicles of 100V or higher), but the risk of electric shock to passengers and maintenance workers can be reduced. it can. Since the insulating coating of the electric wire can be thinned, the weight and volume of the electric wire can be reduced. Moreover, since a large amount of electric power can be input and output with a current amount smaller than 12 V, the volume of the electric motor or generator can be reduced. From these things, it contributes to the fuel consumption reduction effect of the vehicle.

This vehicular system is suitable for accessory parts of such mild hybrid vehicles and is applied as power assist and power regeneration parts. Conventionally, in a mild hybrid vehicle, a CMG, a GMG, a belt drive type starter motor (neither is shown), etc. may be adopted, but these are all power assisted to an internal combustion engine or a power unit. Or, because it regenerates, it is affected by the efficiency of the transmission device and the speed reducer.

Since contrast to the vehicle system of this embodiment is mounted with respect to the driven wheels 10 _B, and the main drive source is disconnected such as an internal combustion engine 35a and the electric motor (not shown), the power regeneration In this case, the kinetic energy of the vehicle body can be directly used. Further, CMG, GMG, when mounting a belt driven starter motor, it is necessary to incorporate in consideration from the design stage of the vehicle 30, it is difficult be retrofitted, for this vehicle to fit in the driven wheel 10 in the _B The electric motor 3 of the system can be installed in a completed vehicle with the same man-hours as parts replacement, and a 48V system can be configured even for a completed vehicle having only the internal combustion engine 35a. A vehicle equipped with the vehicle system of this embodiment may be equipped with another auxiliary drive motor generator 35b as in the example of FIG. In that case, the amount of power assist and the amount of regenerative electric power for the vehicle 30 can be increased, which further contributes to reduction of fuel consumption.

FIG. 15 shows an example in which the vehicle power plant 1 according to any one of the embodiments is applied to the drive wheels 10 _A that are the front wheels and the driven wheels 10 _B that are the rear wheels. The drive wheel _10A is driven by a main drive source 35 composed of an internal combustion engine via a clutch 36 and a speed reducer 37. In this front-wheel drive vehicle, the support and the auxiliary drive of the drive wheels 10 _A and the driven wheels 10 _B, the power unit 1 is installed for a vehicle. In this way, the vehicle power plant 1 can be applied not only to the driven wheels 10 _B but also to the drive wheels 10 _A.

The vehicle system shown in FIG. 13 has a function of generating power, but may be a system that does not rotate and drive by power supply. This vehicle system is equipped with a generator-equipped wheel bearing device including a generator 3 that also does not serve as a motor and a wheel bearing 2. This generator-equipped wheel bearing device has the same configuration as the vehicle power plant of any of the embodiments except for the electric motor.

According to the vehicle system in which the bearing for the wheel with the generator is mounted, the braking force can be generated by storing the regenerative power generated by the generator 3 in the medium voltage battery 49. The braking performance can also be improved by using the mechanical brake operating means 57 in combination or properly. When limited to the function of generating power in this way, the individual control means 39 can be configured as an AC/DC converter device (not shown) instead of an inverter device. The AC/DC converter device has a function of charging the regenerative power of the generator 3 into the medium voltage battery 49 by converting a three-phase AC voltage into a DC voltage, and a control method is easy as compared with an inverter, Miniaturization is possible.

A vehicle power unit and a bearing for a wheel with a generator according to the present application include, as a rotating wheel, a hub wheel in which one partial inner ring is fitted, and an outer ring that is a fixed wheel, and a fitted body of the hub wheel and the partial inner ring. However, the present invention is not limited to this.
A structure including a hub having a hub flange and a member having a raceway surface of a rolling element is a rotating wheel in claims. For example, it may be a first generation structure that mainly includes an outer ring that is a fixed ring and an inner ring that is fitted to the outer peripheral surface of a hub having a hub flange. It may be a second generation structure of an inner ring rotating type that includes an outer ring that is a fixed ring and an inner ring that is fitted to the outer peripheral surface of a hub having a hub flange. In these examples, the combination of the hub and the inner ring corresponds to the "rotating ring" in the claims. It may be a second generation structure of an outer ring rotating type including an outer ring which is a rotating wheel having a hub flange and an inner ring which is a fixed ring.

The electric motor can also be applied to home electric motors, industrial motors, and the like. The generator can be applied to a wind power generator or a hydro power generator.
The ratio of the number N of magnetic poles of the rotor and the number P of grooves between teeth is not limited to P:N=4:5. For example, it may be P:N=8:10 or P:N=12:15.

Although the mode for carrying out the invention has been described based on the embodiment, the embodiment disclosed this time is an exemplification in all respects and is not restrictive. The scope of the present invention is shown not by the above description but by the claims, and is intended to include meanings equivalent to the claims and all modifications within the scope.

2... Wheel bearing, 3... Electric motor (generator), 4... Outer ring (fixed ring), 5... Inner ring (rotating ring), 6... Rolling element, 7... Hub flange, 18... Stator, 18a... Stator core, 18b... Stator coil, 19... Rotor, 20... Annular plate member, 20a... First tooth plate portion, 20b... Annular plate portion, 21... Annular component, 22... Partial plate member, 22a... Second tooth Plate part, 22b... Connecting plate part, 24... Annular member, 30... Vehicle, 31... Non-annular part, Rb... Rib, Ts... Teeth

Claims (9)

An electric motor comprising: a stator having a stator core and a stator coil wound around the stator core; and a rotor positioned to face the stator in a radial direction.
The stator core is
A ring-shaped component in which a plurality of ring-shaped plate-shaped bodies having a plurality of first tooth plate parts radially provided and a ring-shaped plate part to which the base end parts of these first tooth plate parts are connected are stacked,
A plurality of non-circular layers in which a plurality of partial plate-shaped bodies including at least two second tooth plate portions adjacent to each other in the circumferential direction and a connecting plate portion to which the base end portions of these second tooth plate portions are connected are stacked. And a ring part,
The plurality of tooth plates of the first annular plate member and the second tooth plates of the second partial plate member are in phase with each other so that the plurality of tooth plates are arranged in the same phase. An electric motor in which non-circular ring components are arranged in a circle in the circumferential direction. The electric motor according to claim 1, wherein the non-ring parts adjacent to each other in the circumferential direction are arranged such that a wiring gap is formed therebetween. A wheel bearing having a fixed wheel and a rotating wheel rotatably supported by the fixed wheel via rolling elements, and a wheel flange to which a vehicle wheel is attached to a hub flange provided on the rotating wheel, and a wheel bearing An electric motor according to claim 1 or 2, which is attached, wherein the stator is attached to the fixed wheel, and the rotor is attached to the rotating wheel. The vehicle power unit according to claim 3, wherein the teeth of the electric motor are constituted by a plurality of teeth plate portions overlapping in phase, and the electric motor has a number of magnetic poles of the rotor of N and a circumference of the stator. A power unit for a vehicle that is a three-phase permanent magnet synchronous motor in which 2N/3P is not an integer, where P is the number of grooves between teeth that are adjacent in the direction. The vehicle power plant according to claim 3 or 4, wherein the electric motor is an outer rotor type in which the rotor is located radially outward of the stator, and the stator coil is radially inward of the stator core. A power unit for a vehicle in which the wiring portion of the vehicle is arranged. The vehicle power plant according to any one of claims 3 to 5, wherein the non-circular ring component is sandwiched between two circular ring components that are axially spaced from each other. The vehicle power unit is arranged. The vehicle power plant according to any one of claims 3 to 6, wherein each of the first and second teeth plate portions extends straight from the base end portion to the tip end portion, or the tip end portion. A power unit for a vehicle, which is provided with ribs projecting in an arc shape from both sides in the circumferential direction. A generator including a stator having a stator core and a stator coil wound around the stator core, and a rotor positioned to face the stator in a radial direction,
The stator core is
A ring-shaped component in which a plurality of ring-shaped plate-shaped bodies having a plurality of first tooth plate parts radially provided and a ring-shaped plate part to which the base end parts of these first tooth plate parts are connected are stacked,
A plurality of non-circular layers in which a plurality of partial plate-shaped bodies including at least two second tooth plate portions adjacent to each other in the circumferential direction and a connecting plate portion to which the base end portions of these second tooth plate portions are connected are stacked. And a ring part,
The plurality of tooth plates of the first annular plate member and the second tooth plates of the second partial plate member are in phase with each other so that the plurality of tooth plates are arranged in the same phase. A generator in which non-annular components are arranged in a circle and lined up in the circumferential direction. A wheel bearing having a fixed wheel and a rotating wheel rotatably supported by the fixed wheel via rolling elements, and a wheel flange to which a vehicle wheel is attached to a hub flange provided on the rotating wheel, and a wheel bearing A generator according to claim 8, which is attached, wherein the stator is attached to the fixed wheel and the rotor is attached to the rotating wheel.

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