Rotor, rotating electrical machine, and drive device

Abstract

A rotor according to one embodiment of the present invention is provided with: a rotor core extending along a central axis; and a pair of fans which are respectively mounted on the end surfaces of the rotor core facing the two sides in the axial direction. With respect to the fan, the direction in which the end surface of the rotor core to which the fan is mounted faces is set to one side in the axial direction, and the opposite direction is set to the other side in the axial direction. The fan is provided with: a plate-shaped main body part having a first surface facing one side in the axial direction and a second surface facing the other side in the axial direction; and a first rib and a second rib which extend in the circumferential direction in the main body part. The main body part is provided with a first through hole and a second through hole arranged side by side in the circumferential direction, and the first through hole and the second through hole are respectively connected with the first surface and the second surface. The first surface is provided with a first opening that opens the first through-hole and a second opening that opens the second through-hole. The first rib is located at the radially outer edge of the first opening and protrudes toward one side in the axial direction. The second rib is located at the radially inner edge of the second opening and protrudes radially outward.

Description

Technical Field

[0001] The invention relates to a rotor, a rotating electrical machine and a driving device.

[0002] This application claims priority based on Japanese Patent Application No. 2022-157747 filed in Japan on September 30, 2022, the contents of which are cited here. Background Art

[0003] As interest in electric vehicles has increased in recent years, various methods for cooling rotating electrical machines have been developed. For example, a method is known in which a fan disposed at an axial end of a rotor blows air from inside the rotor toward the coil to cool the rotor and the coil (Patent Document 1).

[0004] Prior art literature

[0005] Patent Literature

[0006] Patent Document 1: Japanese Patent Application Publication No. 2011-211862 Summary of the invention

[0007] Problems to be solved by the invention

[0008] In the conventional fan, a wind path for air to flow radially outward is provided between the end surface of the rotor and the fan. Therefore, it is difficult to ensure a large contact area between the fan and the end surface of the rotor, and there is a problem that the fan is difficult to be stably fixed to the rotor.

[0009] In view of the above circumstances, one object of the present invention is to provide a rotor having a fan that can be stably fixed to a rotor core, a rotating electrical machine, and a driving device.

[0010] Means for solving problems

[0011] A rotor according to one embodiment of the present invention comprises: a rotor core extending along a central axis; and a pair of fans, which are respectively mounted on the end faces of the rotor core facing both axial sides. With respect to the fan, the direction in which the end face of the rotor core on which the fan is mounted faces is set as one axial side, and the opposite direction is set as the other axial side. The fan comprises: a main body, which is plate-shaped and has a first face facing one axial side and a second face facing the other axial side; and a first rib and a second rib, which extend circumferentially in the main body. The main body is provided with a first through hole and a second through hole arranged in a circumferential direction, and the first through hole and the second through hole connect the first face and the second face, respectively. The first face is provided with a first opening portion where the first through hole opens and a second opening portion where the second through hole opens. The first rib is located at the radially outer edge of the first opening portion and protrudes to one axial side. The second rib is located at a radially inner edge of the second opening and protrudes radially outward.

[0012] A rotating electrical machine according to one aspect of the present invention includes: the above-mentioned rotor; and a stator located radially outside the rotor.

[0013] A driving device according to one aspect of the present invention includes: the above-described rotating electrical machine; and a power transmission unit that transmits power of the rotating electrical machine.

[0014] Effects of the Invention

[0015] According to one aspect of the present invention, it is possible to provide a rotor having a fan that can be stably fixed to a rotor core, a rotating electrical machine, and a drive device. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 This is a conceptual diagram of the driving device according to the first embodiment.

[0017] Figure 2 It is a perspective view of the fan and the anti-dropping member according to the first embodiment.

[0018] Figure 3 It is a perspective view of the fan according to the first embodiment.

[0019] Figure 4 It is a cross-sectional view of the fan according to the first embodiment.

[0020] Figure 5 It is a cross-sectional view of the fan according to the first embodiment.

[0021] Figure 6 It is a front view showing a method of fixing a fan according to a modified example.

[0022] Figure 7 It is a perspective view showing a fan according to a second embodiment. DETAILED DESCRIPTION

[0023] In the following description, the gravity direction is defined and described based on the positional relationship when the drive device 1 is mounted on a vehicle located on a horizontal road surface.

[0024] In the following description, unless otherwise specified, the direction parallel to the central axis J1 of the rotary electric machine 2 (Y-axis direction) is referred to as the "axial direction", the radial direction centered on the central axis J1 is referred to as the "radial direction", and the circumferential direction centered on the central axis J1, that is, the direction around the central axis J1 is referred to as the "circumferential direction". However, the above-mentioned "parallel direction" also includes a substantially parallel direction.

[0025] <First embodiment>

[0026] <Drive device>

[0027] Figure 1 This is a conceptual diagram of the driving device 1 according to the first embodiment.

[0028] The drive device 1 of the present embodiment is mounted on a vehicle having a rotating electric machine as a power source, such as a hybrid electric vehicle (HEV), a plug-in hybrid electric vehicle (PHV), or an electric vehicle (EV), and is used as the power source thereof.

[0029] The drive device 1 includes a rotating electrical machine 2, a power transmission unit 50, and a housing 6 that accommodates the rotating electrical machine 2 and the power transmission unit 50. The drive device 1 may further include an inverter (not shown) that controls the rotating electrical machine 2.

[0030] <Power transmission unit>

[0031] The power transmission unit 50 is connected to the rotor 20, transmits the power of the rotary electric machine 2 and outputs it to the output shaft 57. The power transmission unit 50 has a first shaft 54, a second shaft 55, a first gear 51, a second gear 52, a third gear 53 and a differential device 56. The differential device 56 has a ring gear 56g and a pair of output shafts 57. Wheels are respectively mounted at the front ends of the pair of output shafts 57.

[0032] The first shaft 54 ​​extends in the axial direction with the center axis J1 as the center. The first shaft 54 ​​is connected to the rotor 20 of the rotary electric machine 2 and rotates together with the rotor 20. The first gear 51 is provided on the outer peripheral surface of the first shaft 54. The second shaft 55 rotates with the intermediate axis J2 parallel to the center axis J1 as the center. The second gear 52 and the third gear 53 are provided on the outer peripheral surface of the second shaft 55. The second gear 52 meshes with the first gear 51. The third gear 53 meshes with the ring gear 56g of the differential device 56. When the vehicle turns, the differential device 56 absorbs the speed difference between the left and right wheels while transmitting the torque transmitted from the third gear 53 to the output shaft 57. The torque output from the rotary electric machine 2 is transmitted to the ring gear 56g of the differential device 56 via the first shaft 54, the first gear 51, the second gear 52, the second shaft 55 and the third gear 53, and is output to the pair of output shafts 57 via the differential mechanism of the differential device 56.

[0033] <Rotary electric machines>

[0034] The rotating electric machine 2 of this embodiment is an inner rotor type three-phase AC motor. The rotating electric machine 2 has both the function of outputting power as a motor and the function of generating electricity as a generator. The rotating electric machine 2 can be used as either a motor or a generator. In addition, the structure of the rotating electric machine 2 is not limited to this embodiment, and for example, it can also be an AC motor with four or more phases.

[0035] The rotating electric machine 2 includes a rotor 20 rotatable about a central axis J1 extending in the horizontal direction, the rotor 20 , and a stator 30 located radially outside the rotor. The rotating electric machine 2 of the present embodiment has the rotor 20 disposed inside the stator 30 .

[0036] <Stator>

[0037] The stator 30 is held by the housing 6. The stator 30 surrounds the rotor 20 from the radially outer side. The stator 30 includes an annular stator core 32 centered on the central axis J1, a coil 31 attached to the stator core 32, and an insulator (not shown) interposed between the stator core 32 and the coil 31.

[0038] The stator core 32 has an annular core back and a plurality of teeth extending radially inward from the core back. The plurality of teeth are arranged circumferentially. Coil wires are arranged between the teeth arranged circumferentially. The coil wires between adjacent teeth constitute the coil 31.

[0039] The coil 31 has a pair of coil ends 31a protruding in the axial direction from the end surfaces on both axial sides of the stator core 32. The coil ends 31a are formed by bundling a part of the coil wire connecting the slots of the stator core 32.

[0040] <Rotor>

[0041] The rotor 20 includes a rotor shaft 21 , a rotor core 24 fixed to the outer peripheral surface of the rotor shaft 21 , a plurality of magnets 25 fixed to the rotor core 24 , a pair of fans 4 , and a pair of retaining members 5 .

[0042] The rotor shaft 21 extends along the central axis J1. The rotor shaft 21 is rotatable about the central axis J1. The rotor shaft 21 is press-fitted into the rotor core 24 and the pair of retaining members 5.

[0043] The rotor core 24 is in a columnar shape extending along the central axis J1. The rotor core 24 has a pair of end faces 24f facing both sides in the axial direction. In addition, the rotor core 24 is provided with a central hole 24c, a plurality of vent holes 24a, 24b, and a plurality of retaining holes 24h. The central hole 24c, the vent holes 24a, 24b, and the retaining holes 24h extend in the axial direction and penetrate the rotor core 24 in the axial direction. The central hole 24c, the vent holes 24a, 24b, and the retaining holes 24h are open on both sides in the axial direction on the pair of end faces 24f.

[0044] The center hole 24c extends in the axial direction with the center axis J1 as the center. In the present embodiment, the center hole 24c is substantially circular when viewed from the axial direction. The rotor shaft 21 is press-fitted into the center hole 24c. The shape of the center hole 24c is not limited to the present embodiment.

[0045] The plurality of vent holes 24a, 24b include the first vent hole 24a and the second vent hole 24b. That is, the rotor core 24 is provided with the first vent hole 24a and the second vent hole 24b. In the present embodiment, the first vent hole 24a and the second vent hole 24b are alternately arranged along the circumferential direction (see Figure 3 ). In the rotor 20 of the present embodiment, four first vent holes 24a and four second vent holes 24b are provided. The cross-sectional shapes of the first vent holes 24a and the second vent holes 24b of the present embodiment are equal to each other. The flow directions of the air flowing inside the first vent holes 24a and the second vent holes 24b are different from each other.

[0046] A plurality of retaining holes 24h are arranged along the circumferential direction. Magnets 25 are respectively accommodated in the retaining holes 24h. The magnets 25 are fixed to the inner side surfaces of the retaining holes 24h by adhesive. In addition, the magnets 25 can also be fixed in the retaining holes 24h by fixing methods such as caulking or pressing. The openings on both axial sides of the retaining holes 24h are respectively covered by the fan 4. Thus, even if a part of the magnet 25 is missing, it is possible to prevent the fragments of the magnet 25 from detaching from the rotor 20.

[0047] <Fan>

[0048] A pair of fans 4 are respectively mounted on the end faces 24f of the rotor core 24 facing both axial sides. The pair of fans 4 rotates around the central axis J1 together with the rotor core 24. The pair of fans 4 are respectively located radially inside the coil end 31a. In the present embodiment, the pair of fans 4 are of the same shape. The installation angles of the pair of fans 4 around the central axis J1 relative to the rotor core 24 are different from each other.

[0049] The fan 4 of this embodiment is made of aluminum alloy and is formed by aluminum die casting. In addition, the fan 4 may be made of a resin material or other metal material.

[0050] Figure 2 and Figure 3 Each of them is a perspective view of the fan 4 .

[0051] In the following description, one of the pair of fans 4 located on the +Y side of the rotor core 24 (the first fan 4A) is described based on the Y axis, but the other fan 4 located on the -Y side of the rotor core 24 (the second fan 4B) also has the same structure. In the following description of the fan 4, the direction in which the end face 24f of the mounted rotor core 24 faces is set as one axial side (the +Y side), and the opposite direction is set as the other axial side (the -Y side).

[0052] like Figure 2 As shown, the fan 4 includes a main body 40 , a first rib 41 , a plurality of (four in this embodiment) second ribs 42 , and a plurality of (eight in this embodiment) third ribs 43 .

[0053] The main body 40 is in the shape of a plate extending perpendicularly to the axial direction. When viewed from the axial direction, the main body 40 is roughly circular with the central axis J1 as the center. That is, when viewed from the axial direction, the main body 40 is roughly in the shape of a circular plate. The main body 40 has a first surface 40a facing one axial side (+Y side) and a second surface 40b facing the other axial side (-Y side).

[0054] The main body 40 is provided with a shaft insertion hole 40h, a plurality of (four in this embodiment) first through holes 45, and a plurality of (four in this embodiment) second through holes 46. The shaft insertion hole 40h, the first through holes 45, and the second through holes 46 penetrate the main body 40 in the axial direction.

[0055] Figure 4 and Figure 5 The diagrams are cross-sectional views of the fan 4 at the first through hole 45 and the second through hole 46. The shaft insertion hole 40h, the first through hole 45, and the second through hole 46 connect the first surface 40a and the second surface 40b, respectively.

[0056] like Figure 2As shown, the shaft insertion hole 40h is a substantially circular shape centered on the central axis. The rotor shaft 21 is inserted into the shaft insertion hole 40h. The inner diameter of the shaft insertion hole 40h is larger than the outer diameter of the rotor shaft 21. The method of fixing the fan 4 to the rotor shaft 21 will be described later.

[0057] like Figure 3 As shown, the first through hole 45 and the second through hole 46 are alternately arranged in the circumferential direction. When viewed from the axial direction, the opening shapes of the first through hole 45 and the second through hole 46 on the second surface 40b are the same shape. The openings of the first through hole 45 and the second through hole 46 on the second surface 40b extend in a substantially arc shape along the circumferential direction.

[0058] When the first fan 4A is observed from the axial direction, the opening of the first through hole 45 on the second surface 40b overlaps with the second ventilation hole 24b, and the opening of the second through hole 46 on the second surface 40b overlaps with the first ventilation hole 24a. On the other hand, although the illustration is omitted, when the second fan 4B is observed from the axial direction, the opening of the first through hole 45 on the second surface 40b overlaps with the first ventilation hole 24a, and the opening of the second through hole 46 on the second surface 40b overlaps with the second ventilation hole 24b.

[0059] Therefore, if Figure 1 As shown, the first ventilation hole 24a is connected to the first through hole 45 of the second fan 4B at the opening on the -Y side, and is connected to the second through hole 46 of the first fan 4A at the opening on the +Y side. In addition, the second ventilation hole 24b is connected to the second through hole 46 of the second fan 4B at the opening on the -Y side, and is connected to the first through hole 45 of the first fan 4A at the opening on the +Y side. That is, the first ventilation hole 24a is connected to the first through hole 45 of one of the pair of fans 4 and the aforementioned second through hole 46 of the other. In addition, the second ventilation hole 24b is connected to the second through hole 46 of one of the pair of fans 4 and the first through hole 45 of the other.

[0060] As described later, the air inside is blown out radially outward from the second through hole 46 by the centrifugal force accompanying the rotation of the fan 4 around the central axis J1. When the rotor 20 rotates, air is blown out from the second through hole 46, thereby generating negative pressure inside the vent holes 24a and 24b connected to the second through hole 46. As a result, air flows from the first through hole 45 into the inside of the vent holes 24a and 24b. In this way, the first through hole 45 functions as an air intake hole for sucking air, and a flow of air along the axial direction is formed in the first vent hole 24a.

[0061] According to the present embodiment, the air in the vent holes 24a and 24b flows from the opening connected to the first through hole 45 toward the opening connected to the second through hole 46. Thus, the inside of the rotor 20 can be cooled by air. In addition, according to the present embodiment, the air flows in different directions in the first vent hole 24a and the second vent hole 24b. Therefore, the reaction force of the air resistance applied to the inner side surface of the first vent hole 24a and the reaction force of the air resistance applied to the inner side surface of the second vent hole 24b cancel each other out. It is possible to suppress the force applied to the rotor 20 in an arbitrary position in the axial direction due to the reaction force of the air resistance.

[0062] like Figure 2 As shown in the figure, the first through hole 45 and the second through hole 46 are opened on the first surface 40a of the main body 40. Here, the opening of the first through hole 45 is referred to as the first opening 45a, and the opening of the second through hole 46 is referred to as the second opening 46a. That is, the first opening 45a where the first through hole 45 is opened and the second opening 46a where the second through hole 46 is opened are provided on the first surface 40a of the main body 40.

[0063] The first opening 45a functions as an air intake port for sucking air into the first through hole 45. The first opening 45a extends in a substantially arc shape along the circumferential direction. The radially outer edge of the first opening 45a is set as the first outer edge 45b, and the radially inner edge is set as the first inner edge 45c. The first outer edge 45b and the first inner edge 45c are opposite to each other in the radial direction. When viewed from the axial direction, the first outer edge 45b and the first inner edge 45c are in a concentric arc shape centered on the central axis J1.

[0064] The second opening 46a functions as a blow-out port for blowing out the air in the second through hole 46. The second opening 46a extends in a substantially arc shape along the circumferential direction. The radially outer edge of the second opening 46a is set as the second outer edge 46b, and the radially inner edge is set as the second inner edge 46c. The second outer edge 46b and the second inner edge 46c are opposite to each other in the radial direction. When viewed from the axial direction, the second outer edge 46b and the second inner edge 46c are in a concentric arc shape centered on the central axis J1.

[0065] The first outer edge portion 45b and the second outer edge portion 46b are arranged on the same virtual circle centered on the central axis J1. That is, the radial positions of the first outer edge portion 45b and the second outer edge portion 46b coincide with each other.

[0066] The second inner edge portion 46c is arranged at a position closer to the radial outside than the first inner edge portion 45c. That is, the radially inner edge of the second opening portion 46a is located closer to the radial outside than the radially inner edge of the first opening portion 45a. Thus, the second opening portion 46a can be arranged closer to the radial outside and close to the coil end portion 31a, so that the air blown out from the second opening portion 46a can effectively contact the coil end portion 31a.

[0067] The second inner edge portion 46c is arranged at a position radially outward from the first inner edge portion 45c, so that the opening area of ​​the second opening portion 46a is smaller than the opening area of ​​the first opening portion 45a. According to the present embodiment, by reducing the opening area of ​​the second opening portion 46a compared to the first opening portion 45a, the air suction efficiency of the first opening portion 45a can be improved, and the flow rate of the air blown out from the second opening portion 46a can be increased. Thus, the flow rate of the air in contact with the coil end portion 31a can be increased to improve the cooling efficiency of the coil end portion 31a.

[0068] The first rib 41 extends in the circumferential direction in the main body 40. The first rib 41 has a substantially annular shape centered on the central axis J1. The first rib 41 protrudes from the first surface 40a of the main body 40 toward one side (+Y side) in the axial direction.

[0069] The first rib 41 is located at the radially outer edge (first outer edge 45b) of the first opening 45a. The first rib 41 guides the flow of air sucked from the first opening 45a. In addition, the fan 4 of the present embodiment is provided with only one first rib 41 extending in a roughly annular shape along the circumferential direction. However, the first rib only needs to be arranged at the radially outer edge of the first opening 45a, and may also be in a form interrupted between the first openings 45a. In addition, the first rib 41 does not necessarily need to be annular, for example, it may also be a polygonal extension surrounding the center axis J when viewed from the axial direction.

[0070] According to the present embodiment, the first rib 41 is also arranged radially outside the second opening 46a, so that a part of the air blown out from the second opening 46a can contact the first rib 41, and the air can be widely scattered in the axial direction. Thus, the air blown out from the second opening 46a can contact a wide range in the axial direction of the coil end 31a.

[0071] According to the present embodiment, the first rib 41 is substantially annular centered on the central axis J1, and thus the rotation stability of the fan 4 can be improved compared to a case where a plurality of first ribs are discretely provided in the circumferential direction. In addition, the substantially annular first rib 41 can be used as a cutting allowance for balance adjustment. That is, in the balance correction process after assembling the rotor 20, by cutting a portion of the circumferential direction of the first rib 41, the imbalance of the rotor 20 can be adjusted. As a cutting method for the first rib 41, for example, drilling is considered to be performed on the radially outward surface of the first rib 41.

[0072] The second rib 42 extends in the main body 40 along the circumferential direction. The second rib 42 is arranged radially inside the first rib 41. That is, the second rib 42 and the first rib 41 are radially opposite. Four second ribs 42 are provided on the fan 4 of this embodiment. The four second ribs 42 are arranged along the circumferential direction. When viewed from the axial direction, the four second ribs 42 are arranged on the same imaginary circle centered on the central axis J1. The second rib 42 is arranged only radially inside the second opening 46a and is interrupted at a portion located radially inside the first opening 45a.

[0073] The second rib 42 is located at the radially inner edge (second inner edge 46c) of the second opening 46a. In addition, the second rib 42 protrudes radially outward. The second rib 42 covers a portion of the radially inner area of ​​the second opening 46a. The second rib 42 guides the air flowing into the second through hole 46 from the vent holes 24a, 24b along the axial direction to the radially outer side.

[0074] According to the fan 4 of the present embodiment, the second rib 42 protruding radially outward is provided at the radially inner edge of the second opening 46a. Therefore, the opening direction of the second opening 46a can be directed radially outward, and the air in the second through hole 46 can be blown radially outward by centrifugal force. In addition, according to the fan 4 of the present embodiment, the first rib 41 protruding axially to one side (+Y side) is provided at the radially outer edge of the first opening 45a. The first rib 41 can guide the air on the axial side (+Y side) of the fan 4 into the first through hole 45 along the axial direction.

[0075] For example, in order to make the blowing direction of the fan face radially outward, it is considered to provide a flow path for blowing between the fan and the end face of the rotor core. In this case, it is difficult to fully ensure the contact area between the fan and the end face of the rotor core. According to the fan 4 of this embodiment, the first through hole 45 that functions as an air intake hole and the second through hole 46 that functions as a blowing hole are both open on both sides of the main body 40. That is, according to the fan 4 of this embodiment, the first through hole 45 and the second through hole 46 both connect the first surface 40a and the second surface 40b of the main body 40. Therefore, there is no need to provide a flow path for blowing on the side of the second surface 40b, and the contact area between the second surface 40b and the rotor core 24 can be ensured to be larger, so that the fan 4 can be stably supported on the rotor core 24. In addition, as Figure 3 As shown, according to this embodiment, by ensuring that the second surface 40b is large, the plurality of holding holes 24h of the rotor core 24 can be covered by the fan 4, and the magnets 25 can be prevented from being separated from the holding holes 24h. That is, according to this embodiment, it is not necessary to provide other components such as a plate for covering the holding holes 24h between the fan 4 and the rotor core 24, and the number of components can be reduced and the rotor 20 can be manufactured at a low cost.

[0076] In the present embodiment, at least a portion of the first through hole 45 and the second through hole 46 penetrates the main body 40 in the axial direction. That is, an observer observing the fan 4 from the axial direction can face the opposite side of the fan 4 via the first through hole 45 and the second through hole 46. In the case where the fan 4 is formed by casting or resin molding as described above, the fan 4 is molded by a mold structure in which a male mold and a female mold are arranged on both sides of the axial direction relative to the cavity filled with the base material. In the case where the first through hole 45 and the second through hole 46 penetrate the main body 40 in the axial direction, the first through hole 45 and the second through hole 46 of the fan 4 can be molded without using a complex mold such as a sliding mold or without performing additional processing. Therefore, the fan 4 can be manufactured inexpensively.

[0077] like Figure 4 and Figure 5 As shown, the second rib 42 is located at a position closer to the axial side (+Y side) than the first opening 45a. According to the present embodiment, the axial positions of the first opening 45a and the second opening 46a can be arranged to be staggered from each other. Thus, the flow of air sucked into the first opening 45a and the flow of air blown out from the second opening 46a can be suppressed from interfering with each other, and the air supply efficiency of the fan 4 can be improved. In addition, by arranging the second opening 46a closer to the axial side (+Y side), the air blown out from the second opening 46a can easily pass over the first rib 41. Thus, the air blown out from the second opening 46a can effectively contact the coil end 31a.

[0078] like Figure 5As shown, the second rib 42 has a first guide surface 42g facing the other axial side (-Y side). The first guide surface 42g is axially opposed to the openings of the vent holes 24a, 24b of the rotor core 24. The first guide surface 42g constitutes the inner wall of the flow path of the air passing through the second through hole 46. The first guide surface 42g is inclined toward one axial side (+Y side) as it moves toward the radial outside. According to the present embodiment, the second rib can smoothly guide the air that flows from the vent holes 24a, 24b in the axial direction and flows into the second through hole 46 to the radial outside in the first guide surface 42g.

[0079] like Figure 2 As shown, the third rib 43 protrudes toward one axial side (+Y side) relative to the main body 40. The third rib 43 extends radially in the main body 40. Eight third ribs 43 are provided on the fan 4 of this embodiment. The eight third ribs 43 are respectively arranged between the first opening 45a and the second opening 46a.

[0080] The third rib 43 of the present embodiment is arranged between the first opening 45a and the second opening 46a to prevent the flow of air sucked into the first opening 45a from interfering with the flow of air blown out from the second opening 46a. According to the fan 4 of the present embodiment, the efficiency of suction and blowing can be improved, and the cooling efficiency of the fan 4 on the coil end 31a can be improved.

[0081] like Figure 3 As shown, the second surface 40b of the main body 40 is in the shape of a plane perpendicular to the axial direction. The main body 40 is opposite to and in contact with the end surface 24f of the rotor core 24 at the second surface 40b. A plurality of (eight in this embodiment) weight-reducing recesses 49 are provided on the second surface 40b. The plurality of weight-reducing recesses 49 extend in a substantially arc shape with the central axis J1 as the center. The weight-reducing recesses 49 are arranged at equal intervals along the circumferential direction. As shown in FIG. Figure 4 As shown, the weight-reducing recess 49 overlaps the first rib 4 when viewed from the axial direction. That is, the weight-reducing recess 49 is formed so as to hollow out the inside of the first rib 41 on the back side of the first rib 41.

[0082] The fan 4 of the present embodiment is a die-cast component. Therefore, the fan 4 is prone to generate pores in the local thick-walled portion. According to the fan 4 of the present embodiment, by providing a weight-reducing recess 49 on the back side of the first rib 41, it is possible to suppress the provision of a local thick-walled portion in the main body 40. Thus, the generation of pores inside the main body 40 can be suppressed, and the dimensional stability of the fan 4 can be improved. In addition, by providing the weight-reducing recess 49 in the main body 40, the fan 4 can be made lighter.

[0083] The opening of the lightening recess 49 on the second surface 40b overlaps with the holding hole 24h of the rotor core 24. Therefore, the internal space of the lightening recess 49 is connected to the internal space of the holding hole 24h. According to the present embodiment, when a part of the magnet 25 disposed in the holding hole 24h is broken, the fragments of the magnet 25 can be left in the lightening recess 49.

[0084] (How to fix the fan)

[0085] The method of fixing the fan 4 to the rotor shaft 21 will be described. The fan 4 is located between the rotor core 24 and the retaining member 5. The fan 4 is sandwiched between the rotor core 24 and the retaining member 5 in the axial direction in a state of being in contact with the rotor core 24 and the retaining member 5, respectively.

[0086] The anti-dropout member 5 is provided to fix the rotor core 24 to the rotor shaft 21. The anti-dropout member 5 is in an annular shape centered on the central axis J1. The anti-dropout member 5 is located on the outer peripheral surface of the rotor shaft.

[0087] In addition, in this specification, "annular" is not limited to being circular, as long as it has a structure that can surround the central axis J1. "Annular" does not necessarily need to be a closed loop, and may be a C-shaped shape that can be regarded as annular as a whole even if there are partially disconnected parts. That is, the anti-drop component 5 only needs to be annular and surround the rotor shaft 21 from the radial outside, and does not need to be a circular ring or a closed loop.

[0088] The rotor core 24, the fan 4, and the anti-slip component 5 are sequentially mounted on the rotor shaft 21. The rotor shaft 21 is fixed to the rotor core 24 by being pressed in. Similarly, the rotor shaft 24 is fixed to the anti-slip component 5 by being pressed in. On the other hand, since the fan 4 is made of a relatively low strength material such as an aluminum alloy, in order to ensure strength when being pressed in relative to the rotor shaft 21, the fan 4 is easily enlarged. In order to be miniaturized, the fan 4 of this embodiment inserts the rotor shaft 21 into the shaft insertion hole 40h in an interlocking state that allows relative movement such as a clearance fit. The fan 4 is sandwiched between the rotor core 24 and the anti-slip component 5 in the axial direction, so that the relative movement in the axial direction is restricted.

[0089] A pair of protrusions 40d protruding axially to one side (+Y side) are provided on the first surface 40a of the fan 4 in the region in contact with the retaining member 5. In addition, a pair of recesses 5e recessed radially inward are provided on the outer peripheral surface of the retaining member 5.

[0090] When the fan 4 and the anti-drop component 5 are assembled to the rotor shaft 21, the convex portion 40d is inserted into the concave portion 5e. As a result, the circumferentially facing surface of the convex portion 40d and the inner surface of the concave portion 5e are circumferentially opposed to each other, and the relative movement of the fan 4 with respect to the anti-drop component 5 in the circumferential direction is restricted. As a result, the fan 4 is restrained from rotating with respect to the rotor shaft 21.

[0091] In addition, in the present embodiment, the case where the convex portion 40d is provided on the main body 40 of the fan 4 and the concave portion 5e is provided on the anti-detachment member 5 is described, but the convex portion and the concave portion may be provided on opposite parts. That is, as long as the convex portion 40d protruding toward the other side is provided on one of the main body 40 and the anti-detachment member 5, and the concave portion 5e into which the convex portion 40d is inserted is provided on the other side.

[0092] In addition, in the present embodiment, the case where the anti-slip component 5 is used to suppress the relative rotation between the fan 4 and the rotor shaft 21 is described. However, the following structure may be adopted: a convex portion and a concave portion are directly provided on the fan 4 and the rotor shaft 21, respectively, thereby suppressing their relative rotation. That is, the following structure may be adopted: a convex portion protruding toward the other side is provided on one of the inner circumferential surface of the shaft insertion hole 40h of the fan 4 and the outer circumferential surface of the rotor shaft 21, and a concave portion for inserting the convex portion is provided on the other side. The following structure may also be adopted: opposing concave portions (keyways) are provided on the inner circumferential surface of the shaft insertion hole 40h and the outer circumferential surface of the rotor shaft 21, and other components (keys) are inserted into the space where the concave portions are connected to each other.

[0093] (Variation of the method for fixing the fan)

[0094] Figure 6 This is a front view of a fan 104 showing a modified example of the fixing method of the fan 104 that can be adopted in the above embodiment. The fixing method of this modified example restricts the relative movement of the fan 104 in the circumferential direction with respect to the anti-detachment member 105 in the same manner as in the above embodiment, but the structure related to the restriction is different.

[0095] In the description of this modification, the same reference numerals are given to the same components as those of the already described embodiment, and the description thereof will be omitted.

[0096] The anti-drop member 105 is fixed to the rotor shaft 21 by press-fitting the rotor shaft 21 as in the above embodiment. On the other hand, the fan 104 is inserted with the rotor shaft 21 in a state where relative rotational movement around the central axis J1 is allowed with respect to the rotor shaft 21.

[0097] The anti-detachment member 105 is annular centered on the central axis J1. A plurality of grooves 105g are provided on the outer peripheral surface of the anti-detachment member 105. The grooves 105g of this embodiment are substantially semicircular when viewed from the axial direction, but the shape is not limited.

[0098] The fan 104 has a surrounding wall portion 148 extending circumferentially with the central axis J1 as the center. The surrounding wall portion 148 has an end surface 148b facing one axial side (+Y side) and an inner side surface 148a facing radially inward. The inner side surface 148a of the surrounding wall portion 148 is radially opposite to the groove portion 105g provided on the outer peripheral surface of the anti-detachment component 105.

[0099] The surrounding wall portion 148 has a plurality of caulking portions 147. The caulking portions 147 are located radially outside the groove portion 105g of the anti-slip component 105. A plurality of caulking portions 147 are provided on the end face 148b of the surrounding wall portion 148. The caulking portions 147 are arranged along the radially inner end of the end face 148b of the surrounding wall portion 148. The caulking portions 147 are formed by applying pressure to the end face 148b using a caulking jig to cause the end face 148b to undergo plastic deformation. The caulking portions 147 are recessed toward the other axial side (-Y side) and protrude radially inwardly due to plastic deformation in the forming stage. The caulking portions 147 are arranged inside the groove portion 105g at the portion protruding radially inwardly. According to the present embodiment, a portion of the caulking portion 147 is circumferentially opposed to the inner side surface of the groove portion 105g that faces the circumferential direction. As a result, the relative movement of the fan 104 in the circumferential direction with respect to the retaining member 105 is restricted, and the rotation of the fan 104 with respect to the rotor shaft 21 is further suppressed.

[0100] <Second embodiment>

[0101] Figure 7 It is a perspective view showing the fan 204 according to the second embodiment.

[0102] The fan 204 of the second embodiment can be adopted in the rotor 20, the rotary electric machine 2, and the drive device 1 of the above-described embodiment. Components having the same form as those of the above-described embodiment are denoted by the same reference numerals, and their description is omitted.

[0103] Similar to the above-mentioned embodiment, the fan 204 has: a plate-shaped main body 240; a first rib 241 and a second rib 242, which extend in the circumferential direction in the main body 240; and a third rib 243, which extends in the radial direction in the main body 240. The main body 240 has a first surface 240a facing one axial side (+Y side) and a second surface 240b facing the other axial side. The main body 240 is provided with a first through hole 245 and a second through hole 246 arranged in the circumferential direction, and the first through hole 245 and the second through hole 246 connect the first surface 240a and the second surface 240b, respectively. In addition, a first opening 245a where the first through hole 245 opens and a second opening 246a where the second through hole 246 opens are provided on the first surface 240a. The first rib 241 is located at the radially outer edge of the first opening 245a and protrudes to one axial side (+Y side). The second rib 242 is located at the radially inner edge of the second opening 246a and protrudes to the radially outer side. The third rib 243 is arranged between the first opening 245a and the second opening 246a in the circumferential direction and protrudes to one axial side.

[0104] In this embodiment, four first ribs 241 are provided on the fan 204. The four first ribs 241 are discretely arranged along the circumferential direction and are respectively located at radially outer edges of different first openings 245a. Therefore, the first rib 241 is interrupted at a portion located radially outer of the second opening 246a.

[0105] The first surface 240a of the main body 240 has a second guide surface 240c extending radially outward from the radially outer edge of the second opening 246a. The second guide surface 240c is located between the plurality of first ribs 241 arranged in the circumferential direction. The second guide surface 240c extends along a plane perpendicular to the axial direction.

[0106] According to the present embodiment, by providing the second guide surface 240c in the main body 240, the air blown out from the second opening 246a passes along the second guide surface 240c between the first ribs 241. Therefore, the flow of the air blown out from the second opening 246a can contact the coil end 31a without being weakened by the first rib 241, so the cooling efficiency of the coil end 31a can be improved.

[0107] In addition, you can also Figure 7As shown by the double-dotted line in the figure, at least one fin 240f extending in the radial direction is provided on the second guide surface 240c. In this case, the air flowing along the second guide surface 240c can be rectified by the fin 240f, and the turbulence of the air toward the coil end 31a can be suppressed. According to this structure, the flow of air toward the coil end 31a can be made to contact the coil end 31a without diffusion, and the cooling efficiency of the coil end 31a can be further improved.

[0108] The third rib 243 of the present embodiment has a side wall surface 243a facing the second opening portion 246a side in the circumferential direction. The side wall surface 243a is inclined toward the opposite side of the second opening portion 246a in the circumferential direction as it moves toward the radially outer side. The side wall surface 243a is arranged on both sides of the circumferential direction relative to the second opening portion 246a. Therefore, the path of the air blown out from the second opening portion 246a to the radially outer side expands toward both sides of the circumferential direction as it moves toward the radially outer side. According to the present embodiment, the pressure loss of the air blown out from the second opening portion 246a becomes smaller, and strong wind can be widely transported to the coil end portion 31a along the circumferential direction.

[0109] The fan 204 of this embodiment is fixed to the rotor shaft 21 in the same manner as in the above-mentioned embodiment. Figure 4 In FIG. 1 , the illustration of the protrusion for preventing rotation provided in the shaft insertion hole 240h of the fan 204 is omitted.

[0110] The various embodiments and modifications of the present invention have been described above, but each structure and combination thereof in each embodiment and modification is an example, and addition, omission, substitution and other changes of the structure can be made within the scope of the gist of the present invention. In addition, the present invention is not limited by the embodiments.

[0111] For example, in the above embodiment, the coil is a bendable wire mounted on the stator, and the lead wire extending from the coil has a structure obtained by bundling a plurality of wires using a crimping terminal. However, the coil may also be a segmented coil composed of a highly rigid flat wire, and the lead wire extending from the coil is also a single flat wire.

[0112] In addition, the present technology can adopt the following structures.

[0113] (1) A rotor, comprising: a rotor core extending along a central axis; and a pair of fans, the pair of fans being mounted on end surfaces of the rotor core facing both axial sides, respectively. With respect to the fans, the direction in which the end surfaces of the rotor core facing the fans are facing is set as one axial side, and the opposite direction is set as the other axial side. The fans comprise: a main body portion in a plate shape, having a first surface facing one axial side and a second surface facing the other axial side; and a first rib and a second rib, the first rib and the second rib extending in the circumferential direction in the main body portion, a first through hole and a second through hole arranged in the circumferential direction are provided in the main body portion, the first through hole and the second through hole respectively connecting the first surface and the second surface, a first opening portion in which the first through hole opens and a second opening portion in which the second through hole opens are provided on the first surface, the first rib is located at an edge portion on the radially outer side of the first opening portion and protrudes toward one axial side, and the second rib is located at an edge portion on the radially inner side of the second opening portion and protrudes toward the radially outer side.

[0114] (2) The rotor according to (1), wherein the radially inner edge of the second opening is located radially outward of the radially inner edge of the first opening.

[0115] (3) The rotor according to (1) or (2), wherein the second rib is located axially closer to one side than the first opening.

[0116] (4) The rotor according to any one of (1) to (3), wherein the second rib has a first guide surface facing the other axial side, and the first guide surface is inclined toward the axial one side as it goes toward the radially outer side.

[0117] (5) A rotor according to any one of (1) to (4), wherein the fan has a third rib extending radially in the main body, the third rib being circumferentially arranged between the first opening and the second opening, and the third rib protruding axially to one side.

[0118] (6) The rotor according to (5), wherein the third rib has a side wall surface facing the second opening in the circumferential direction, and the side wall surface is inclined toward the opposite side of the second opening in the circumferential direction as it goes toward the radially outer side.

[0119] (7) The rotor according to any one of (1) to (6), wherein at least a portion of the first through hole and the second through hole penetrates the main body in the axial direction.

[0120] (8) The rotor according to any one of (1) to (7), wherein the first rib has an annular shape centered on the central axis.

[0121] (9) A rotor according to any one of (1) to (8), wherein the first surface has a second guide surface extending radially outward from a radially outer edge of the second opening, and the second guide surface is located between a plurality of the first ribs arranged in the circumferential direction.

[0122] (10) The rotor according to (9), wherein at least one fin extending in the radial direction is provided on the second guide surface.

[0123] (11) A rotor according to any one of (1) to (10), wherein a first ventilation hole and a second ventilation hole extending axially therethrough are provided on the rotor core, the first ventilation hole being connected to the first through hole of one of a pair of fans and the second through hole of the other, and the second ventilation hole being connected to the second through hole of one of a pair of fans and the first through hole of the other.

[0124] (12) A rotor according to any one of (1) to (11), wherein the rotor has a plurality of magnets, a plurality of retaining holes extending axially therethrough are provided on the rotor core, the magnets are accommodated in the retaining holes, and the openings of the retaining holes are covered by the fan.

[0125] (13) A rotor according to any one of (1) to (12), wherein the rotor comprises: a rotor shaft extending along a central axis; and an annular anti-slip component located on an outer peripheral surface of the rotor shaft, wherein the main body of the fan is provided with an axis insertion hole for inserting the rotor shaft, the fan is located between the rotor core and the anti-slip component, and a convex portion protruding toward the other side is provided on one of the main body and the anti-slip component, and a concave portion for inserting the convex portion is provided on the other side.

[0126] (14) A rotating electrical machine comprising: a rotor as described in any one of (1) to (13); and a stator located radially outside the rotor.

[0127] (15) A drive device comprising: the rotating electrical machine described in (14); and a power transmission unit that transmits power from the motor.

[0128] Description of symbols

[0129] 1: drive device; 2: rotating motor; 4, 104, 204: fan; 5, 105: anti-dropping component; 5e: recess; 20: rotor; 21: rotor shaft; 24: rotor core; 24a: first vent hole; 24b: second vent hole; 24f: end surface; 24h: holding hole; 25: magnet; 30: stator; 40, 240: main body; 40a, 240a: first surface; 40b, 240b: second surface; 40d: convex portion ; 40h: shaft insertion hole; 41, 241: 1st rib; 42, 242: 2nd rib; 42g: 1st guide surface; 43, 243: 3rd rib; 45, 245: 1st through hole; 45a, 245a: 1st opening; 46, 246: 2nd through hole; 46a, 246a: 2nd opening; 50: power transmission part; 240c: 2nd guide surface; 240f: fin; 243a: side wall surface; J1: center axis.

Claims

1. A rotor comprising: a rotor core extending along a central axis; and A pair of fans, the pair of fans are respectively mounted on the end surfaces of the rotor core facing both sides of the axial direction, Regarding the fan, the direction in which the end face of the rotor core on which the fan is installed faces is set as one axial side, and the opposite direction is set as the other axial side. The fan has: a main body portion, which is plate-shaped and has a first surface facing one axial side and a second surface facing the other axial side; and a first rib and a second rib, the first rib and the second rib extending in the circumferential direction in the main body, The main body is provided with a first through hole and a second through hole arranged in a circumferential direction, the first through hole and the second through hole connecting the first surface and the second surface respectively. The first surface is provided with a first opening portion where the first through hole is opened and a second opening portion where the second through hole is opened, The first rib is located at the radially outer edge of the first opening and protrudes toward one side in the axial direction. The second rib is located at a radially inner edge of the second opening and protrudes radially outward.

2. The rotor according to claim 1, wherein: The radially inner edge of the second opening is located radially outward of the radially inner edge of the first opening.

3. The rotor according to claim 1, wherein: The second rib is located axially closer to one side than the first opening.

4. The rotor according to claim 1, wherein: The second rib has a first guide surface facing the other axial side. The first guide surface is inclined toward one side in the axial direction as it goes toward the radially outer side.

5. The rotor according to claim 1, wherein: The fan has a third rib extending in the radial direction in the main body. The third rib is disposed between the first opening and the second opening in the circumferential direction, and the third rib protrudes to one side in the axial direction.

6. The rotor according to claim 5, wherein: The third rib has a side wall surface facing the second opening in the circumferential direction. The side wall surface is inclined toward the opposite side of the second opening in the circumferential direction as it goes toward the radially outer side.

7. The rotor according to claim 1, wherein: At least a portion of the first through hole and the second through hole penetrates the main body in the axial direction.

8. The rotor according to claim 1, wherein: The first rib is in a circular ring shape centered on the central axis.

9. The rotor according to claim 1, wherein: The first surface has a second guide surface extending radially outward from a radially outer edge of the second opening. The second guide surface is located between the plurality of first ribs arranged in the circumferential direction.

10. The rotor according to claim 9, wherein: The second guide surface is provided with at least one fin extending in the radial direction.

11. The rotor according to claim 1, wherein: The rotor core is provided with a first vent hole and a second vent hole which penetrate in the axial direction. The first ventilation hole is connected to the first through hole of one of the pair of fans and the second through hole of the other fan. The second ventilation hole is connected to the second through hole of one of the pair of fans and the first through hole of the other fan.

12. The rotor according to claim 1, wherein: The rotor has a plurality of magnets. The rotor core is provided with a plurality of retaining holes penetrating in the axial direction. The magnet is received in the holding hole. The opening of the holding hole is covered by the fan.

13. The rotor according to claim 1, wherein: The rotor has: a rotor shaft extending along a central axis; and The anti-dropping component is annular and located on the outer peripheral surface of the rotor shaft. The main body of the fan is provided with a shaft insertion hole for inserting the rotor shaft. The fan is located between the rotor core and the anti-dropping component. One of the main body and the anti-detachment member is provided with a convex portion protruding toward the other side, and the other is provided with a concave portion into which the convex portion is inserted.

14. A rotating electrical machine, comprising: A rotor as claimed in any one of claims 1 to 13; and The stator is located radially outside the rotor.

15. A driving device, comprising: The rotating electrical machine according to claim 14; and A power transmission unit transmits power of the rotating electric machine.

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