JP6172066B2 - In-wheel motor for vehicle - Google Patents

Description

  The present invention relates to an in-wheel motor assembled to a wheel.

  Conventionally, a vehicle that travels by an in-wheel motor assembled to a wheel has been developed. As a type of in-wheel motor, an inner rotor type and an outer rotor type are known. The inner rotor type is configured by arranging a stator around which a coil is wound on the outside and housing a rotor provided with a permanent magnet inside the stator. On the other hand, the outer rotor type, on the other hand, is configured by disposing a rotor provided with a permanent magnet on the outside and housing a stator on which a coil is wound inside the rotor.

  The heat generated in the coil is released through the motor housing in the inner rotor type in-wheel motor, but in the outer rotor type in-wheel motor, the stator around which the coil is wound is arranged inside the rotor. So it is easy to get inside. In particular, direct drive type outer rotor type in-wheel motors that do not require a reduction gear require high torque, so the amount of heat generated by the coil is large, and a technique that releases heat accumulated in the stator well is required. ing.

  Patent Document 1 proposes a technique for improving the heat dissipation of an outer rotor type in-wheel motor. The in-wheel motor proposed in Patent Document 1 fills the gap between the rotor and the stator with cooling oil to make the heat distribution inside the motor uniform. In addition, a reservoir tank that stores cooling oil is provided outside the in-wheel motor, and the reservoir tank and the gap are connected by a pipe. This reservoir tank is open to the atmosphere, and even if the volume of the cooling oil in the in-wheel motor changes due to a temperature change, the volume of the cooling oil can be received or supplied.

JP-A-2005-333706

  However, the technique proposed in Patent Document 1 requires a special device (referred to as an external device) such as a reservoir tank outside the in-wheel motor and a pipe connecting the in-wheel motor and the reservoir tank. For this reason, it is necessary to provide an extra space for arranging the external device. Accordingly, the degree of freedom in designing around the wheel is reduced. Moreover, it is necessary to newly take measures to prevent the cooling oil from leaking from the external device by providing the external device.

  An object of the present invention is to cope with the above problem, and is to cool a coil winding portion in an outer rotor type in-wheel motor without providing an external device.

In order to achieve the above object, the features of the present invention are:
A stator (50) having a coil winding portion (55) in which a coil is wound around an iron core;
An outer rotor (10) having a permanent magnet (14) disposed so as to cover the periphery of the stator and facing the coil winding portion, and the stator is connected to the vehicle body side member (100) In the in-wheel motor of the vehicle in which the outer rotor is connected to the wheel side member (200),
The cooling oil stored in the storage portion (21) in the lower portion of the outer rotor where the cooling oil is stored by its own weight is moved upward along the inner peripheral surface of the outer rotor by the rotating force of the outer rotor. And a cooling mechanism (30, 35, 38, 39, 40, 41, 43, 45) for releasing into the space area in the outer rotor and contacting with the coil winding portion.

  An in-wheel motor for a vehicle according to the present invention includes an outer including a stator having a coil winding portion, and an outer rotor having a permanent magnet provided so as to cover the periphery of the stator and facing the coil winding portion. It is a rotor type in-wheel motor. In this in-wheel motor, the stator is coupled to the vehicle body side member, and the outer rotor is coupled to the wheel side member.

  The vehicle in-wheel motor of the present invention includes a cooling mechanism. The cooling mechanism is a lower part in the outer rotor, and the cooling oil stored in the storage part in which the cooling oil is stored by its own weight is raised upward along the inner peripheral surface of the outer rotor by the rotating force of the outer rotor. After that, it is discharged into a space area in the outer rotor and brought into contact with the coil winding portion. Thereby, a coil winding part is cooled with cooling oil. In this case, since the space region is provided in the outer rotor, it is not necessary to provide an external device that absorbs the thermal expansion of the cooling oil. Therefore, according to the present invention, the coil winding portion can be cooled without providing an external cooling device outside the in-wheel motor.

  A feature of one aspect of the present invention is that the cooling mechanism is formed on the inner circumferential surface of the outer rotor at predetermined intervals in the circumferential direction, and the cooling oil that is accumulated in the storage portion by the rotation of the outer rotor is scraped up. It is in having a part (30, 38, 40, 43).

  The cooling mechanism according to one aspect of the present invention includes a fried portion. The raking part is formed on the inner peripheral surface of the outer rotor at a predetermined circumferential interval, and ravels the cooling oil accumulated in the accumulating part by the rotation of the outer rotor. As a result, the cooling oil accumulated in the reservoir can be well raised along the inner peripheral surface of the outer rotor. Therefore, the coil winding part can be cooled satisfactorily. In this case, the hoisting portion may be provided, for example, on both sides in the width direction of the permanent magnet and between the width direction end surface of the permanent magnet and the width direction side wall inner surface of the outer rotor.

  A feature of one aspect of the present invention is that the hoisting portion is provided with an inclined plate (30, 30) that is erected from an inner circumferential surface of the outer rotor with an inclination angle (θ) that is an acute angle with respect to a motor rotation direction when the vehicle advances. 38).

  The cooling mechanism according to one aspect of the present invention includes an inclined plate as the fried portion. The inclined plate is erected from the inner peripheral surface of the outer rotor at an inclination angle that is an acute angle with respect to the motor rotation direction when the vehicle moves forward. That is, the inclined plate is erected from the inner peripheral surface of the outer rotor, and is provided such that an angle formed with a tangent line extending from the erected position toward the motor rotation direction when the vehicle moves forward is an acute angle. When the vehicle moves forward, the outer rotor rotates and turns in the direction in which the inclined plate is inclined in accordance with this rotation. Thereby, sufficient cooling oil required for cooling a coil winding part can be stirred up. Further, the cooled cooling oil can be dropped so as to be in good contact with the coil winding portion. Therefore, the coil winding part can be cooled satisfactorily.

  One aspect of the present invention is that the inclined plate is configured such that the inclination angle (θ) increases as the rotational speed of the outer rotor in the vehicle forward direction increases.

  In one aspect of the present invention, the inclination angle of the inclined plate increases as the rotational speed of the outer rotor in the vehicle forward direction increases. Since the inclined plate turns around the motor shaft by the rotation of the outer rotor, the inclined plate is urged in the direction opposite to the turning direction by the turning force. Therefore, for example, by using this urging force, the inclination angle of the inclined plate can be increased.

  The greater the tilt angle of the tilt plate, that is, the closer the tilt angle of the tilt plate is to a right angle, the easier the cooling oil pumped up by the tilt plate falls. On the other hand, the higher the rotational speed of the outer rotor in the vehicle forward direction, the more difficult the cooling oil falls due to centrifugal force. In one aspect of the present invention, by these two actions, the cooling oil can be discharged well into the space region in the outer rotor, regardless of whether the outer rotor rotates in the forward direction of the vehicle. Can be contacted. Therefore, the coil winding part can be cooled satisfactorily.

  A feature of one aspect of the present invention is that the lifting portion is a protrusion (40, 43) protruding inward from the inner peripheral surface of the outer rotor.

  The cooling mechanism in one side of the present invention is provided with a projection as a raking part. The protrusion is provided so as to protrude inward from the inner peripheral surface of the outer rotor. When the outer rotor rotates, the protrusion turns around the motor shaft in accordance with the rotation. As a result, the cooling oil accumulated in the reservoir can be satisfactorily scooped up by the protrusion. Therefore, the coil winding part can be cooled satisfactorily.

  A feature of one aspect of the present invention is that the cooling mechanism is fixed to the stator, and a protrusion contact member that drops the cooling oil pumped up by the protrusion by contacting the tip of the protrusion. (41).

  The cooling mechanism in one side of the present invention is provided with the projection contact member. When the outer rotor rotates, the cooling oil accumulated in the reservoir is lifted upward by the protrusion. The protrusion contact member comes into contact with the tip of the protrusion and drops the cooling oil pumped up by the protrusion. Thereby, cooling oil can be favorably discharged into the space region in the outer rotor and brought into contact with the coil winding portion. Therefore, the coil winding part can be cooled satisfactorily. For example, the tip of the protrusion may be formed in a smooth curved surface.

  A feature of one aspect of the present invention is that the cooling mechanism is fixed to the stator, and is cooled upward along the inner peripheral surface of the outer rotor and attached to the inner peripheral surface. It is provided with a guide passage member (45) that is introduced by centrifugal force acting on the cooling oil and led to the coil winding portion.

  The cooling mechanism according to one aspect of the present invention includes a guide passage member. The guide path member is fixed to the stator, and is introduced by cooling force that is raised upward along the inner peripheral surface of the outer rotor and adhered to the inner peripheral surface by centrifugal force acting on the cooling oil. Lead to the turning part. For example, when the rotation speed of the outer rotor is high, there is a possibility that the cooling oil may be returned to the storage portion while being attached to the inner peripheral surface of the outer rotor due to centrifugal force. Oil is introduced into the guide path member by centrifugal force and guided to the coil winding portion. Therefore, the coil winding part can be cooled satisfactorily.

  A feature of one aspect of the present invention is that the cooling mechanism is fixed to the stator and is raised upward along the inner peripheral surface of the outer rotor and contacts the cooling oil attached to the inner peripheral surface. Thus, a cooling oil contact member (35, 39, 41) for dropping the cooling oil from the inner peripheral surface is provided.

  The cooling mechanism according to one aspect of the present invention includes a cooling oil contact member. The cooling oil contact member is fixed to the stator, and is raised upward along the inner peripheral surface of the outer rotor and comes into contact with the cooling oil attached to the inner peripheral surface, and the cooling oil drops from the inner peripheral surface. Let When the rotation speed of the outer rotor is high, there is a possibility that the cooling oil may be returned to the storage portion while being attached to the inner peripheral surface of the outer rotor by centrifugal force. Since the member contacts the cooling oil adhering to the inner peripheral surface, the cooling oil can be surely dropped into the space region in the outer rotor and brought into contact with the coil winding portion. Therefore, the coil winding part can be cooled satisfactorily.

  In the above description, in order to help the understanding of the invention, the reference numerals used in the embodiments are attached to the configuration of the invention corresponding to the embodiment in parentheses, but each constituent element of the invention is the reference numeral. It is not limited to the embodiment defined by.

It is an internal structure figure which represented roughly the wheel with which the in-wheel motor was assembled | attached, seeing from the vehicle front-back direction. It is sectional drawing showing the internal structure of the in-wheel motor provided with the cooling mechanism concerning Embodiment 1, Comprising: (a) is the schematic seen from the vehicle front-back direction, (b) is seen from the vehicle width direction. FIG. It is a figure explaining the inclination-angle variable operation | movement of the fraying board concerning the modification of Embodiment 1. FIG. It is sectional drawing showing the internal structure of the in-wheel motor provided with the cooling mechanism concerning Embodiment 2, Comprising: (a) is the schematic seen from the vehicle front-back direction, (b) is seen from the vehicle width direction. FIG. It is sectional drawing showing the internal structure of the in-wheel motor provided with the cooling mechanism concerning Embodiment 3, Comprising: (a) is the schematic seen from the vehicle front-back direction, (b) was seen from the vehicle width direction. FIG. It is sectional drawing showing the internal structure of the in-wheel motor provided with the cooling mechanism concerning Embodiment 4, Comprising: (a) is the schematic seen from the vehicle front-back direction, (b) was seen from the vehicle width direction. FIG. It is sectional drawing showing the internal structure of the in-wheel motor provided with the cooling mechanism concerning Embodiment 5, Comprising: (a) is the schematic seen from the vehicle front-back direction, (b) is seen from the vehicle width direction. FIG. It is explanatory drawing showing the induction | guidance | derivation principle of the cooling oil by the cooling oil induction tube concerning Embodiment 5. FIG.

  Hereinafter, an in-wheel motor according to an embodiment of the present invention will be described. FIG. 1 is an internal structure diagram schematically showing a wheel W assembled with an in-wheel motor 1 as viewed from the front-rear direction of the vehicle. In FIG. 1, the left side is the outside in the vehicle width direction. In the in-wheel motor 1 shown in FIG. 1, description of the cooling mechanism described later is omitted. As for the cooling mechanism, five embodiments will be described with reference to FIGS.

  The in-wheel motor 1 includes an outer rotor 10 and a stator 50. The outer rotor 10 has a main body composed of a cylindrical portion 11 that forms a yoke and opposing side plate portions 12 and 13 that close both ends in the width direction (both ends in the axial direction) of the cylindrical portion 11. On the inner peripheral surface 11a of the cylindrical portion 11 (hereinafter referred to as the cylindrical inner peripheral surface 11a), a magnet 14 (permanent magnet) magnetized alternately with N and S poles along the circumferential direction at the center in the width direction. It is arranged in an annular shape. On both sides in the width direction of the magnet 14, ring-shaped depressions 20 surrounded by the end surface 14 a of the magnet 14, the inner wall surfaces 12 a and 13 a of the side plates 12 and 13, and the cylindrical inner peripheral surface 11 a of the cylindrical portion 11 are formed. Has been. The outer rotor 10 is rotatably supported on the stator 50 by bearings 15 and 16 provided on the side plate portions 12 and 13 facing each other. The width direction means the direction in which the center axis of the in-wheel motor 1 faces and is the same as the wheel width direction when the in-wheel motor 1 is assembled to the wheel W.

  The stator 50 includes a shaft portion 51 that rotatably supports the outer rotor 10 via bearings 15 and 16, and an iron core portion 52 provided at the center of the shaft portion 51. The iron core portion 52 has a cylindrical shape that is coaxial with the shaft portion 51, and a coil 54 is wound around a plurality of grooves 53 formed on the outer peripheral side. The entire outer peripheral side of the iron core portion 52 around which the coil 54 is wound is referred to as a coil winding portion 55. The coil winding portion 55 is annularly disposed so as to face the magnet 14 of the outer rotor 10 with an air gap having a predetermined length therebetween. The shaft portion 51 and the iron core portion 52 may be integrally formed, or may be configured by connecting separate parts.

  The in-wheel motor 1 is connected to the vehicle body side member 100 at the shaft portion 51 of the stator 50. For example, the shaft portion 51 of the stator 50 extends to the inner side in the vehicle width direction than the outer rotor 10, and a connecting portion 60 is provided at the tip thereof. This connection part 60 is connected with the vehicle body side member 100 (for example, carrier) by the connection metal fitting which is not illustrated. The vehicle body side member 100 is connected to the vehicle body B via a suspension device 80 (suspension arm, suspension spring, shock absorber, etc.).

  The in-wheel motor 1 is connected to the metal wheel 200 (wheel side member) on which the tire 300 is mounted in the side plate portion 12 of the outer rotor 10. For example, the stud bolt 17 is fixed to the side plate portion 12, and the nut 18 is tightened from the tip of the stud bolt 17 in a state where the stud bolt 17 is inserted into the bolt insertion hole 201 of the metal wheel 200. Fastened to the rotor 10.

  Next, a cooling mechanism for cooling the coil winding portion 55 will be described. The in-wheel motor 1 of this embodiment is an outer rotor type in-wheel motor. For this reason, since the coil winding part 55 is arrange | positioned inside the outer rotor 10, the heat | fever generate | occur | produced with the coil 54 tends to be confined inside. Further, since the direct drive system does not require a reduction gear, it is necessary to generate a high torque, and the amount of heat generated by the coil 54 is large. Therefore, in the in-wheel motor 1 of the present embodiment, a cooling mechanism for cooling the coil winding portion 55 is provided. Hereinafter, five embodiments regarding the cooling mechanism will be described.

<First Embodiment>
2A and 2B are cross-sectional views showing the internal structure of the in-wheel motor 1 provided with the cooling mechanism according to the first embodiment. FIG. 2A is a schematic view viewed from the front-rear direction of the vehicle, and FIG. It is the schematic seen from the vehicle width direction. Cooling oil O is injected into the outer rotor 10. The cooling oil O accumulates in the recessed portions 20 provided on the left and right sides of the magnet 14. The cooling oil O is set to an amount such that the oil level is lower (in the direction of gravity) than the lowest position on the inner peripheral surface of the magnet 14 in a state where the cooling oil O is accumulated below the depression 20. Hereinafter, the lower part of the hollow part 20, that is, a region where the cooling oil O accumulates due to gravity is referred to as a storage part 21. About the structure of the storage part 21, and the quantity of the cooling oil O, it is the structure similar to 1st Embodiment also about other embodiment (2nd Embodiment-5th Embodiment) mentioned later.

  The cooling mechanism raises the cooling oil O accumulated in the reservoir 21 upward along the cylindrical inner peripheral surface 11a of the outer rotor 10 (the inner peripheral surface of the recess 20) by the rotating force of the outer rotor 10. After that, it is discharged into a space region in the outer rotor 10 and brought into contact with the coil winding portion 55.

  In the hollow portion 20 of the outer rotor 10, a frying plate 30 is provided as a cooling mechanism at a predetermined interval along the circumferential direction. The scraper plate 30 is formed on the cylindrical inner peripheral surface 11a of the outer rotor 10 so as to extend to the full width direction of the recess 20 so as to partition the recess 20 at equal intervals in the circumferential direction. The scraper plate 30 is integrally formed from a fixed portion 31 fixed to the cylindrical inner peripheral surface 11 a of the outer rotor 10 and an inclined plate portion 32 extending from the fixed portion 31 toward the inner side of the outer rotor 10. The extending direction of the inclined plate portion 32 is inclined in the motor rotation direction (meaning the direction in which the outer rotor 10 rotates when the vehicle travels forward) rather than the direction toward the rotation center of the outer rotor 10. In other words, the inclined plate portion 32 is a flat plate standing from the cylindrical inner peripheral surface 11a of the outer rotor 10, and an inclination angle formed with a tangent extending from the standing position to the motor rotation direction side when the vehicle moves forward. It is provided so that θ is an acute angle. In this example, a plurality of lifting plates 30 are fixedly provided in the recessed portions 20. For example, a ring-shaped plate in which a plurality of inclined plate portions 32 are formed at equal intervals is used as a cylinder of the outer rotor 10. You may make it fix to the internal peripheral surface 11a.

  Next, the operation of this cooling mechanism (kakiage plate 30) will be described. When the coil 54 is energized, the outer rotor 10 rotates. The rotation direction indicated by the arrow in FIG. 2B represents the rotation direction of the outer rotor 10 when the vehicle moves forward. Due to the rotation of the outer rotor 10, the filing plate 30 turns around the motor shaft. When the vehicle travels forward, the lifting plate 30 turns to the inclined side of the inclined plate portion 32. Thereby, the cooling oil O collected in the storage unit 21 is scooped up by the scooping plate 30. In this case, since the inclination angle θ of the inclined plate portion 32 is an acute angle, the cooling oil O is supplied to the cylindrical inner peripheral surface 11 a of the outer rotor 10, the inclined plate portion 32, the end surface 14 a of the magnet 14, and the outer rotor 10. The side plates 12 and 13 are fried up in a state where they are accumulated in the region surrounded by the inner wall surfaces 12a and 13a. Accordingly, the cooling oil O is raised upward along the cylindrical inner peripheral surface 11a of the outer rotor 10 as the outer rotor 10 rotates.

  As the inclined plate portion 32 moves upward with the rotation of the outer rotor 10, its direction (direction from the proximal end toward the distal end) changes, approaches the horizontal from the front from the uppermost position, and moves downward further when moving further upward. Change. Due to such a change in the direction of the inclined plate portion 32, the cooling oil O that has been scooped up by the scooping plate 30 is discharged into a space region in the outer rotor 10 as shown by a thick arrow in FIG. Thereby, the cooling oil O is dripped at the coil winding part 55 and cools the coil winding part 55.

According to the in-wheel motor 1 provided with the cooling mechanism of 1st Embodiment demonstrated above, there exist the following effects.
1. The cooling oil O accumulated in the reservoir 21 is lifted upward along the cylindrical inner peripheral surface 11 a of the outer rotor 10 by the rotating force of the outer rotor 10, and then discharged to the space region in the outer rotor 10. Then, the coil winding portion 55 is brought into contact. Thereby, the coil winding part 55 is favorably cooled by the cooling oil O. As a result, even an outer rotor type in-wheel motor that tends to accumulate heat inside can release heat to the outside via the cooling oil.

  2. Since the space region is provided in the outer rotor 10, there is no need to provide an external device that absorbs the thermal expansion of the cooling oil O as in the conventional device (Patent Document 1). Therefore, the in-wheel motor 1 can be radiated well without providing an external cooling device. Further, it is not necessary to take a separate measure to prevent the cooling oil O from leaking from the external cooling device. For this reason, a cooling mechanism can be comprised at low cost. Further, it is not necessary to provide a space for arranging the cooling external device, and the degree of freedom in designing around the wheel W is improved.

  3. Since a pump for pumping the cooling oil O and a pump pipe are not required, the cooling mechanism can be configured at low cost.

  4). The cooling oil O is set to an amount such that the oil level is lower (lower in the direction of gravity) than the lowest position on the inner peripheral surface of the magnet 14 in a state where the cooling oil O is accumulated in the reservoir 21. By reducing the amount of the cooling oil O in this way, the resistance to rotation of the outer rotor 10 can be reduced. Therefore, power consumption can be suppressed.

  5. Since the cooling oil O is lifted by the scraping plate 30 formed on the cylindrical inner peripheral surface 11a of the outer rotor 10 (the inner peripheral surface of the hollow portion 20), sufficient cooling oil necessary for cooling the coil winding portion 55 is supplied to the outer rotor. It is possible to scoop along 10 cylindrical inner peripheral surfaces 11a. Further, the chilled cooling oil can be dropped so as to make good contact with the coil winding portion 55. Therefore, the coil winding part 55 can be favorably cooled.

<Modification of First Embodiment>
In the first embodiment, the inclination angle θ of the inclined plate portion 32 is constant, but the inclination angle θ may be configured to vary according to the rotational speed of the outer rotor 10. For example, it can be implemented by giving the kakiage plate 30 spring properties. Since the scraper plate 30 turns around the motor shaft by the rotation of the outer rotor 10, the inclined plate portion 32 is urged in the direction opposite to the turning direction by the turning force. Accordingly, as shown in FIG. 3, the frying plate 30 is deformed so that the inclination angle θ increases as the rotation speed of the outer rotor 10 increases, and the inclination angle θ increases to the initial angle as the rotation speed of the outer rotor 10 decreases. The deformation returns so as to approach θo (inclination angle when the outer rotor 10 is not rotating).

  The larger the inclination angle θ of the inclined plate portion 32, that is, the closer the inclination angle θ is to a right angle, the more easily the cooled cooling oil O falls. On the other hand, the faster the outer rotor 10 rotates, the more difficult it is for the cooling oil O to fall due to centrifugal force. That is, the cooling oil O stays in a region sandwiched between the inclined plate portion 32 and the cylindrical inner peripheral surface 11a of the outer rotor 10 and is difficult to fall. Therefore, according to this modification, the cooling oil O can be discharged well into the space region in the outer rotor 10 and brought into contact with the coil winding portion 55 regardless of whether the rotation speed of the outer rotor 10 is high or low. it can. As a result, the heat release of the in-wheel motor 1 can be performed more satisfactorily.

  In addition, in this modification, although the spring property of the fried board 30 itself is utilized, it is not restricted to it. For example, the inclined plate portion 32 is pivotally supported on the cylindrical inner peripheral surface 11a of the outer rotor 10 so that the inclination angle can be changed, and a spring member (not shown) is interposed between the inclined plate portion 32 and the cylindrical inner peripheral surface 11a of the outer rotor 10. It is also possible to employ a configuration in which the inclination angle θ is variable according to the rotational speed of the outer rotor 10 by interposing it and deforming the spring member.

Second Embodiment
4A and 4B are cross-sectional views showing the internal structure of the in-wheel motor 2 provided with the cooling mechanism according to the second embodiment. FIG. 4A is a schematic view seen from the vehicle front-rear direction, and FIG. It is the schematic seen from the vehicle width direction. In the space area in the outer rotor 10, scraping plates 35 are respectively provided at the uppermost positions of the left and right recesses 20. Each scraping plate 35 is a member constituting a cooling mechanism, and is fixed to the stator 50 via a support arm 36. The scraping plate 35 is a square metal flat plate, the plate surface of which is directed vertically and in the width direction, and the upper end surface 35a is slightly spaced from the cylindrical inner peripheral surface 11a at the uppermost position of the outer rotor 10. Arranged so as to face each other. The scraper plate 35 is set to have a width dimension slightly smaller than the width of the recessed portion 20, and its left and right end surfaces are connected to the end surface 14 a of the magnet 14 and the inner wall surfaces 12 a and 13 a of the side plate portions 12 and 13. It is designed not to touch.

  Next, the operation of this cooling mechanism will be described. When the coil 54 is energized, the outer rotor 10 rotates. Since the cooling oil O stored in the storage part 21 has viscosity, a part of the cooling oil O adheres to the cylindrical inner peripheral surface 11 a of the outer rotor 10, that is, the inner peripheral surface of the recessed part 20, and Swirl along with the rotation. If the cooling oil O adhering to the cylindrical inner peripheral surface 11 a of the outer rotor 10 falls due to its own weight at a position where it is lifted upward, the cooling oil O can be brought into contact with the coil winding portion 55. However, when the rotation speed of the outer rotor 10 is high, the centrifugal force acting on the cooling oil O becomes large, so that the cooling oil O may not fall while adhering to the cylindrical inner peripheral surface 11a. Therefore, in the second embodiment, the cooling oil O adhering to the cylindrical inner peripheral surface 11a is scraped and dropped by the scraping plate 35.

  The scraping plate 35 has an upper end surface 35a provided close to the inner circumferential surface 11a of the cylinder at the uppermost position of the outer rotor 10, so that the path of the cooling oil O adhering to the inner circumferential surface 11a is obstructed. Contact cooling oil O. Thereby, the cooling oil O can be scraped off from the cylindrical inner peripheral surface 11a at the uppermost position in a non-contact manner. The scraped cooling oil O is discharged into a space region in the outer rotor 10 as indicated by a thick arrow in FIG. Thereby, the cooling oil O is dripped at the coil winding part 55 and cools the coil winding part 55.

According to the in-wheel motor 2 provided with the cooling mechanism of the second embodiment described above, the following effect 6 is obtained in addition to the effects 1 to 4 in the first embodiment.
6). Since the scraping plate 35 scrapes the cooling oil O adhering to the cylindrical inner peripheral surface 11 a of the outer rotor 10 at the uppermost position, the cooling oil O can be reliably dropped onto the coil winding portion 55. Therefore, the coil winding part 55 can be favorably cooled. Further, since the scraping plate 35 is provided so as not to come into contact with the cylindrical inner peripheral surface 11a, an increase in the rotational resistance of the outer rotor 10 can be minimized, and also due to contact with the cylindrical inner peripheral surface 11a. There is no noise.

<Modification of Second Embodiment>
In the second embodiment, the scraping plate 35 is provided in a non-contact manner with respect to the cylindrical inner peripheral surface 11a. For example, a brush (not shown) is provided instead of the scraping plate 35, and the brush The structure which makes the front-end | tip contact the cylinder inner peripheral surface 11a may be sufficient. According to this modification, the cooling oil O adhering to the cylindrical inner peripheral surface 11a can be more reliably scraped off. Moreover, since the brush is used, an increase in the rotational resistance of the outer rotor 10 and an increase in noise due to contact can be suppressed.

<Third Embodiment>
5A and 5B are cross-sectional views showing the internal structure of the in-wheel motor 3 provided with the cooling mechanism according to the third embodiment, wherein FIG. 5A is a schematic view seen from the vehicle front-rear direction, and FIG. It is the schematic seen from the vehicle width direction. The cooling mechanism according to the third embodiment is a cooling mechanism according to the first embodiment and the cooling mechanism according to the second embodiment. As in the first and second embodiments, the in-wheel motor 3 includes a reservoir 21 in which the cooling oil O accumulates below the ring-shaped recesses 20 provided on the left and right sides of the magnet 14. Here, the recess 20 is divided into two in the width direction, and the side close to the magnet 14 is called a first recess 201 and the side close to the side plates 12 and 13 is called a second recess 202. On the cylindrical inner peripheral surface 11a of the outer rotor 10 forming the first hollow portion 201, a scraping plate 38 is provided at a predetermined interval along the circumferential direction. On the other hand, the scraping plate 38 is not provided in the second hollow portion 202, and instead, the scraping plate 39 is provided at the uppermost position. The scraping plate 39 is fixed to the stator 50 via the support arm 36.

  The frying plate 38 provided in the first hollow portion 201 is obtained by halving the width dimension of the frying plate 35 of the first embodiment, that is, by cutting out the outer half in the width direction. Accordingly, the scooping plate 38 includes portions corresponding to the fixed portion 31 and the inclined plate portion 32 in the scooping plate 35 of the first embodiment, but the description thereof is omitted here in order to avoid redundant description.

  The scraping plate 39 provided in the second hollow portion 202 is obtained by halving the width dimension of the scraping plate 35 of the second embodiment, that is, by cutting the inner half in the width direction. The scraper plate 39 is disposed so as to avoid the path of the scraper plate 38 and the upper end surface 39a faces the cylindrical inner peripheral surface 11a at the uppermost position of the outer rotor 10 with a slight separation.

  Next, the operation of this cooling mechanism will be described. When the coil 54 is energized, the outer rotor 10 rotates. When the outer rotor 10 rotates at a low speed, the cooling oil O that has been scooped up by the scooping plate 38 is discharged into a space region in the outer rotor 10. Thereby, the cooling oil O is dripped at the coil winding part 55 and cools the coil winding part 55.

  When the outer rotor 10 rotates at a high speed, the cooling oil O that has been scooped up by the scooping plate 38 remains in a region sandwiched between the scooping plate 38 and the cylindrical inner peripheral surface 11a of the outer rotor 10 by centrifugal force. A case in which it is difficult to release into the space region in the outer rotor 10 is conceivable. Even in such a case, the scraping plate 39 scrapes the cooling oil O adhering to the cylindrical inner peripheral surface 11a of the second recess 202 of the outer rotor 10 at the uppermost position. Thereby, the cooling oil O is dripped at the coil winding part 55 and cools the coil winding part 55.

  According to the in-wheel motor 3 provided with the cooling mechanism of 3rd Embodiment demonstrated above, there exists the effect 1-6 in 1st Embodiment and 2nd Embodiment.

<Modification of Third Embodiment>
In the said 3rd Embodiment, although the cooling mechanism of 1st Embodiment and the cooling mechanism of 2nd Embodiment are arranged in parallel, for example, the modification of 1st Embodiment, or 2nd Embodiment. Modifications can be combined as appropriate.

<Fourth embodiment>
6A and 6B are cross-sectional views showing the internal structure of the in-wheel motor 4 provided with the cooling mechanism according to the fourth embodiment, wherein FIG. 6A is a schematic view seen from the vehicle front-rear direction, and FIG. It is the schematic seen from the vehicle width direction. In the left and right hollow portions 20 of the outer rotor 10, the lifting ridges 40, which are members constituting the cooling mechanism, are provided at predetermined intervals along the circumferential direction. Each lifting ridge 40 is a ridge that has a substantially semicircular cross section protruding in the direction of the rotation center of the outer rotor 10 and extends in the width direction of the recess 20. Therefore, the hoisting ridge 40 has a smooth curved surface at the tip. In the present embodiment, the hoisting ridge 40 is a component fixed to the cylindrical inner peripheral surface 11a of the outer rotor 10, but may be integrally formed on the cylindrical inner peripheral surface 11a. As shown in FIG. 6 (b), the height of the hoisting ridge 40 from the cylindrical inner peripheral surface 11 a is set lower than the liquid level of the coolant accumulated in the reservoir 21 (the liquid level at the deepest portion). ing. Therefore, the hoisting ridge 40 is configured to turn with the rotation of the outer rotor 10, and to be immersed in the cooling liquid that is entirely accumulated in the storage unit 21 during the turning.

  In the space area in the outer rotor 10, scraping plates 41 are respectively provided at the uppermost positions of the left and right recesses 20. Each scraping plate 41 is a member constituting a cooling mechanism, and is fixed to the stator 50 via the support arm 36. The scraping plate 41 is a square rubber flat plate, the plate surface of which is directed in the vertical direction and the vehicle width direction, and the upper end surface 41a is in contact with the tip of the scraping ridge 40 (the tip in the protruding direction). Be placed. Further, the scraper plate 41 is set to have a width dimension slightly smaller than the width of the recessed portion 20, and the left and right end surfaces thereof are the end surface 14 a of the magnet 14 and the inner wall surfaces 12 a of the side plate portions 12 and 13. It does not come into contact with 13a.

  Next, the operation of this cooling mechanism will be described. When the coil 54 is energized, the outer rotor 10 rotates. Due to the rotation of the outer rotor 10, the hoisting ridge 40 turns around the motor shaft. Thereby, the cooling oil O collected in the storage part 21 is scooped up along the cylindrical inner peripheral surface 11a by the scooping protrusion 40. A part of the cooling oil O that has been lifted up by the hoisting ridge 40 is discharged into the space region in the outer rotor 10 and falls onto the coil winding portion 55 before reaching the uppermost position. Further, a part of the cooling oil O that has reached the uppermost position without being discharged into the space region in the outer rotor 10 is scraped off by the scraping plate 41 coming into contact with the tip of the scooping ridge 40, and the outer rotor 10. Is released into the inner space area. Thereby, the cooling oil O is dripped at the coil winding part 55 and cools the coil winding part 55.

According to the in-wheel motor 4 provided with the cooling mechanism of the fourth embodiment described above, in addition to the operational effects 1 to 4 in the first embodiment, the following operational effect 7 is achieved.
7). Since the cooling oil O is scraped upward using the scraping ridge 40 and the scraping plate 41 is brought into contact with the tip of the scraping ridge 40 at the uppermost position, the cooling oil O is scraped off, so that the amount is larger than that in the second embodiment. The cooling oil O can be efficiently dropped onto the coil winding portion 55. Therefore, the coil winding part 55 can be favorably cooled.

<Modification of Fourth Embodiment>
In the said 4th Embodiment, although the rubber flat plate is used as the scraping board 41, the member which contacts the scraping protrusion 40 in the uppermost position is not restricted to a rubber flat plate, The inner peripheral surface of the outer rotor 10 Even if it contacts, the rotation resistance of the outer rotor 10 and the member which can suppress the increase in the noise by contact should just be suppressed. For example, a brush may be used.

<Fifth Embodiment>
FIG. 7 is a cross-sectional view showing the internal structure of the in-wheel motor 5 provided with the cooling mechanism according to the fifth embodiment, where (a) is a schematic view seen from the vehicle front-rear direction, and (b) is a schematic view. It is the schematic seen from the vehicle width direction. The in-wheel motor 5 includes a storage portion 21 in which the cooling oil O accumulates below the ring-shaped recess portions 20 provided on the left and right sides of the magnet 14 as in the above-described embodiment. Here, similarly to the third embodiment, the hollow portion 20 is divided into two in the width direction, the side close to the magnet 14 is called the first hollow portion 201, and the side close to the side plate portions 12, 13 is the second hollow portion 202. Call it. On the cylindrical inner peripheral surface 11a of the outer rotor 10 forming the first hollow portion 201, the lifting ridges 43 are provided at predetermined intervals along the circumferential direction. On the other hand, the scooping ridge 43 is not provided in the second depression 202, and a cooling oil guide tube 45 is provided at the uppermost position instead. The cooling oil guide tube 45 is fixed to the stator 50 via the support arm 46. The cooling mechanism is composed of a raking ridge 43 and a cooling oil guide tube 45.

  The lifting ridge 43 provided in the first recess 201 is obtained by halving the width dimension of the lifting ridge 40 of the fourth embodiment, that is, by cutting the outer half in the width direction. As shown in FIG. 8, the cooling oil guide tube 45 provided at the uppermost position of the second hollow portion 202 is close to the cylindrical inner peripheral surface 11 a of the outer rotor 10 in the second hollow portion 202 and extends in the horizontal direction. A pipe 45a, a vertical pipe 45b that is bent downward from the outer side in the width direction of the upper horizontal pipe 45a and extends in the vertical direction, and is bent inward in the width direction from the lower end of the vertical pipe 45b and extends in the horizontal direction. The lower horizontal pipe portion 45c is integrally formed. A cooling oil inlet 45d that opens toward the first recess 201 is formed in the upper horizontal pipe portion 45a. Further, a cooling oil outlet 45e that opens toward the first recess 201 is formed in the lower horizontal pipe portion 45c.

  Next, the operation of this cooling mechanism will be described. When the coil 54 is energized, the outer rotor 10 rotates. By the rotation of the outer rotor 10, the hoisting ridge 43 turns around the motor shaft. Thereby, the cooling oil O collected in the storage unit 21 is scooped up by the scooping ridge 43. When the rotational speed of the outer rotor 10 is slow, the cooling oil O lifted up by the lifting ridge 43 drops at an upper position and is dropped onto the coil winding portion 55. Further, when the rotation speed of the outer rotor 10 is high, the cooling oil O is applied to the cylindrical inner peripheral surface 11a of the outer rotor 10 (the inner peripheral surface of the first recess 201 between the lifting ridges 43) by centrifugal force. It becomes sticky. Further, the cooling oil O is pressurized by centrifugal force and pushed out to the outside in the width direction of the cylindrical inner peripheral surface 11 a of the outer rotor 10. At this time, since the pressure in the cooling oil guide tube 45 is maintained substantially equal to the atmospheric pressure, the cooling oil O flows into the cooling oil guide tube 45 from the cooling oil inlet 45d. In this way, the cooling oil O is discharged from the cooling oil outlet 45 e of the cooling oil guide tube 45 to the coil winding portion 55 to cool the coil winding portion 55.

According to the in-wheel motor 5 provided with the cooling mechanism of the fifth embodiment described above, the following operational effects 8 are provided in addition to the operational effects 1 to 4 of the first embodiment.
8). Since the cooling oil O is lifted upward using the raking ridge 43 and the cooling oil O is guided into the cooling oil guide tube 45 using the centrifugal force acting on the cooling oil O, the rotation speed of the outer rotor 10 is high. Even in this case, the cooling oil O can be discharged to the coil winding portion 55 satisfactorily. Therefore, the coil winding part 55 can be favorably cooled.

<Modification of Fifth Embodiment>
In the fifth embodiment, as a guide path member for guiding the cooling oil O to the coil winding portion 55, the cooling having a shape integrally formed by the upper horizontal tube portion 45a, the vertical tube portion 45b, and the lower horizontal tube portion 45c. Although the oil guide tube 45 is used, the guide path member is not limited to such a shape, and for example, a tube formed in an arc shape or the like may be employed.

  As mentioned above, although embodiment and the modification which concern on the in-wheel motor of the vehicle of this invention were described, this invention is not limited to the said embodiment and modification, Various unless it deviates from the objective of this invention. It can be changed.

  For example, in the third embodiment, instead of the scooping plate 38, a scooping ridge 43 (see FIG. 7) is provided so that the scooping ridge 43 and the scraping plate 39 are arranged in the width direction in the recess portion 20. The configuration can also be adopted. Further, in the configuration, a scraping plate (a plate in which the width dimension of the scraping plate 41 in FIG. 6 is halved) that contacts the tip of the scooping protrusion 43 can be provided.

  Further, for example, in the fifth embodiment, instead of the scooping ridge 43, a scooping plate 38 (see FIG. 5) is provided so that the scooping plate 38 and the cooling oil guiding tube 45 are arranged in the width direction in the recess portion 20. A configuration provided side by side can also be employed.

  1, 2, 3, 4, 5 ... in-wheel motor, 10 ... outer rotor, 11 ... cylindrical portion, 11a ... cylindrical inner peripheral surface, 12, 13 ... side plate portion, 14 ... magnet, 20 ... recessed portion, 21 ... reserved 30, 38... Kaki plate, 31... Fixed portion, 32. Inclined plate portion, 35, 39, 41... Scraper plate, 40, 43. DESCRIPTION OF SYMBOLS ... Shaft part, 52 ... Iron core part, 54 ... Coil, 55 ... Coil winding part, 60 ... Connection part, 80 ... Suspension apparatus, 100 ... Car body side member, 200 ... Metal wheel, 300 ... Tire, W ... Wheel, (theta) ... tilt angle, O ... cooling oil.

Claims (7)

A stator having a coil winding portion in which a coil is wound around an iron core;
An outer rotor having a permanent magnet provided so as to cover the periphery of the stator and arranged to face the coil winding portion, the stator being connected to a vehicle body side member, and the outer rotor being a wheel side member In-wheel motor of a vehicle connected to
The cooling oil stored in the storage portion where the cooling oil is stored by its own weight in the lower portion of the outer rotor is lifted upward along the inner peripheral surface of the outer rotor by the rotating force of the outer rotor. from Bei example the cooling mechanism into contact with the coil winding part and releases the space area in the outer rotor,
The cooling mechanism is
An in-wheel motor for a vehicle, comprising a scooping portion that is formed on an inner peripheral surface of the outer rotor at a predetermined circumferential interval and that scoops up cooling oil that has accumulated in the storage portion by rotation of the outer rotor . The in-wheel motor for a vehicle according to claim 1,
The hoisting portion is an in-wheel motor for a vehicle, which is an inclined plate that is erected from an inner peripheral surface of the outer rotor with an inclination angle that is an acute angle with respect to a motor rotation direction when the vehicle moves forward . The in-wheel motor for a vehicle according to claim 2,
The inclining plate is a vehicle in-wheel motor configured such that the inclination angle increases as the rotational speed of the outer rotor in the vehicle forward direction increases . The in-wheel motor for a vehicle according to claim 1 ,
The said hoisting part is an in-wheel motor of a vehicle which is a protrusion which protrudes inward from the internal peripheral surface of the said outer rotor . The in-wheel motor for a vehicle according to claim 4 ,
The cooling mechanism is
An in-wheel motor for a vehicle , comprising: a protrusion contact member that is fixed to the stator and contacts the tip of the protrusion to drop the cooling oil pumped up by the protrusion . A stator having a coil winding portion in which a coil is wound around an iron core;
An outer rotor having a permanent magnet provided so as to cover the periphery of the stator and arranged to face the coil winding portion;
In an in-wheel motor of a vehicle in which the stator is connected to a vehicle body side member and the outer rotor is connected to a wheel side member,
The cooling oil stored in the storage portion where the cooling oil is stored by its own weight in the lower portion of the outer rotor is lifted upward along the inner peripheral surface of the outer rotor by the rotating force of the outer rotor. From the cooling mechanism to be released to the space region in the outer rotor and contact the coil winding portion,
The cooling mechanism is
Cooling oil that is fixed to the stator and is raised along the inner peripheral surface of the outer rotor and adhered to the inner peripheral surface is introduced by centrifugal force acting on the cooling oil, and the coil winding is performed. An in-wheel motor for a vehicle including a guide passage member that leads to a section . A stator having a coil winding portion in which a coil is wound around an iron core;
An outer rotor having a permanent magnet provided so as to cover the periphery of the stator and arranged to face the coil winding portion;
In an in-wheel motor of a vehicle in which the stator is connected to a vehicle body side member and the outer rotor is connected to a wheel side member,
The cooling oil stored in the storage portion where the cooling oil is stored by its own weight in the lower portion of the outer rotor is lifted upward along the inner peripheral surface of the outer rotor by the rotating force of the outer rotor. From the cooling mechanism to be released to the space region in the outer rotor and contact the coil winding portion,
The cooling mechanism is
The cooling oil is dropped from the inner peripheral surface by being fixed to the stator and being lifted upward along the inner peripheral surface of the outer rotor and contacting the cooling oil adhering to the inner peripheral surface. An in-wheel motor for a vehicle, comprising a cooling oil contact member to be moved.

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