Rotor

Abstract

To provide a structure for cooling a coil with high efficiency by a simple configuration.SOLUTION: A rotor comprising: an annular rotor core having a plurality of teeth protruding radially outward and arranged in a circumferential direction, and a slot formed between the teeth in the circumferential direction; a field winding wound around the teeth; an insulating member disposed along a wall surface of the slot between the wall surface of the slot and the field winding; and a supply portion having a hole for supplying a coolant between the insulating member and the wall surface of the slot from a radially inner side of the rotor core.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a rotor. [Background technology]

[0002] Conventionally, there are known techniques for cooling coils in wound field rotors with a coolant. For example, Patent Document 1 discloses a technique for forming a passage (reference numeral 8 in FIG. 1) for circulating a coolant inside a member (reference numeral 6 in FIG. 1) that fills the circumferential gap formed between field windings wound around adjacent teeth. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] German Patent Application Publication No. 102023103931 Summary of the Invention [Problem to be solved by the invention]

[0004] In conventional technology, it is necessary to provide a passage for circulating the coolant inside the member that fills the gaps between the field windings, which tends to complicate the sealing structure and increase the number of parts.In addition, because the coolant is circulated inside the member that fills the gaps between the field windings, heat exchange occurs between the coolant and the coil through this member, making it difficult to cool the coil efficiently.

[0005] The present invention has been made in view of the above-mentioned problems, and aims to provide a technique that can provide a structure for cooling a coil with high efficiency using a simple configuration. [Means for solving the problem]

[0006] In one embodiment, the rotor comprises an annular rotor core having a plurality of teeth that protrude radially outward and are arranged circumferentially, and slots formed circumferentially between the teeth; a field winding wound around the teeth; an insulating member arranged along the wall surface of the slot between the wall surface of the slot and the field winding; and a supply portion having a hole that supplies coolant between the insulating member and the wall surface of the slot from the radial inside of the rotor core.

[0007] That is, coolant is supplied from the radially inner side of the rotor core through the holes between the insulating members and the wall surfaces of the slots. The insulating members are generally thinner than the wedge members that fill the gaps between the coils. Therefore, when coolant is supplied between the insulating members and the wall surfaces of the slots, the coolant can efficiently cool the coils. This allows for highly efficient cooling of the coils with a simpler configuration than a configuration in which coolant is circulated inside the wedge members. [Brief explanation of the drawings]

[0008] [Figure 1] FIG. [Figure 2] FIG. 2 is a perspective view of a rotor with some members omitted. [Figure 3] FIG. 3A is a cross-sectional view of the rotor, and FIG. 3B is an enlarged view of the cross-section of the rotor. [Figure 4] 4A and 4B are perspective views showing an end plate. [Figure 5] 2 is a cross-sectional view showing a rotor core cut along a plane parallel to the axial direction. FIG. [Figure 6] 6 is a cross-sectional view showing the end plate and the shaft cut along line AA shown in FIG. 5. FIG. [Figure 7] 7A and 7B are perspective views showing the rotor with its axial direction oriented vertically. DETAILED DESCRIPTION OF THE INVENTION

[0009] Here, the embodiments of the present invention will be described in the following order. (1) Rotor configuration: (2) Cooling configuration: (3) Other embodiments:

[0010] (1) Rotor configuration: 1 and 2 are perspective views of a rotor 1 according to this embodiment, and FIG. 3A is a cross-sectional view of the rotor 1 cut in a direction perpendicular to the axial direction at a certain cutting position Ct (see FIG. 1) in the axial direction. FIG. 2 is a view of the rotor 1 shown in FIG. 1 with the field winding 40 and wedge members 50 omitted. In addition, in the drawings in this specification, components may be omitted or simplified. For example, the shapes of the individual windings of the field winding 40 shown in FIGS. 1 and 3A are omitted, and the spaces occupied by the multiple windings are shown by white areas.

[0011] The rotor 1 according to this embodiment is a wound-field rotor. That is, the rotor 1 is attached to a shaft 2 and rotates around a rotation axis Ax, which is the central axis of the shaft 2. In this specification, the direction parallel to the rotation axis Ax is called the axial direction, the direction perpendicular to the rotation axis Ax is called the radial direction, and the direction of rotation around the rotation axis Ax is called the circumferential direction. In addition, in the radial direction, the direction away from the rotation axis Ax is called the radially outward direction, and the direction approaching the rotation axis Ax is called the radially inward direction.

[0012] The rotor 1 includes an annular rotor core 10. The rotor core 10 includes a plurality of teeth 20 that protrude radially outward. The plurality of teeth 20 are evenly arranged in the circumferential direction, and in this embodiment, there are a total of eight teeth 20. Slots 30 are formed between adjacent teeth 20. The slots 30 house the field winding 40 wound around the teeth 20. That is, a predetermined number of turns of the field winding 40 are wound around each tooth 20. A portion of the field winding 40 wound around the teeth 20 becomes a housing portion housed in the slots 30, and the remaining portion becomes a coil end portion that is positioned at both ends in the axial direction and sandwiches the teeth 20. In FIG. 1, the coil end portion of the field winding 40 is mainly visible, and the individual windings in the coil end portion are shown as white regions without distinction.

[0013] In this embodiment, an insulating member 70 is disposed between the wall surface of the slot 30 and the field winding 40. FIG. 3B is a diagram illustrating one slot 30 extracted from the cross section of the rotor core 10 shown in FIG. 3A, with the hatching of the teeth 20 and the wedge members 50 omitted, the field winding 40 hatched, and the insulating member 70 colored black. The insulating member 70 is an insulating member for preventing electrical conduction between the field winding 40 and the rotor core 10, and is a thin plate-like member made of paper, resin, or the like. The insulating member 70 is disposed along the wall surface 30 a of the slot 30. That is, the insulating member 70 is disposed over the entire surface of the wall surface 30 a of the slot 30 so as to be in contact with the wall surface 30 a of the slot 30.

[0014] In this embodiment, the insulating member 70 is a thin rectangular plate that is bent so that the largest surface of the rectangle is in contact with the wall surface 30a of the slot 30, thereby forming a shape that conforms to the wall surface 30a of the slot 30. Specifically, the teeth 20 have tooth-side protrusions 20a that protrude circumferentially from the outermost radial position. The spaces between the circumferentially adjacent teeth 20 that are radially inward of the tooth-side protrusions 20a are the slots 30. The slots 30 are regions in which the field winding 40 is housed.

[0015] The slots 30 have the same cross-sectional shape in a direction perpendicular to the axial direction over the entire axial length of the rotor core 10. That is, the shape formed by the wall surfaces 30a of the slots 30 formed between circumferentially adjacent teeth 20 in a cross section perpendicular to the axial direction is the same at all axial positions. In this embodiment, in a cross section perpendicular to the axial direction, the wall surfaces 30a of the slots 30 are wall surfaces that extend circumferentially at the radially innermost position, extend radially from the radially inner side to the radially outer side, and extend circumferentially again at the radially outer side. However, at the radially outer side, the wall surfaces 30a of the slots 30 are not connected.

[0016] The insulating member 70 is bent to have the same shape as the wall surface 30a so that it is positioned along each position of the wall surface 30a that changes from the inside to the outside in the radial direction. As a result, as shown in Fig. 3B, the insulating member 70 is present across the entire surface of the wall surface 30a, and the wall surface 30a and the insulating member 70 are in substantial contact with each other. However, the wall surface 30a and the insulating member 70 are not joined, and a gap may occur between them as shown in Fig. 3B.

[0017] 3B, when the field windings 40 are wound around adjacent teeth 20, gaps are formed between adjacent field windings 40 in the circumferential direction. In this embodiment, wedge members 50 are attached to fill these gaps. By filling the circumferential gaps formed between the field windings 40 with the wedge members 50, it is possible to prevent the field windings 40 from shifting or collapsing during use of the rotor 1.

[0018] The wedge member 50 has a wedge-member-side protrusion 50a that protrudes in the circumferential direction at its radially outermost position. The wedge member 50 is shaped to fill gaps between adjacent field windings 40. That is, in a cross section perpendicular to the axial direction as shown in FIG. 3B , the wedge member 50 is shaped to follow the outer shape of the field winding 40 so that no gap is formed (or almost no gap is formed) between the field winding 40 and the wedge member 50. Specifically, in a cross section perpendicular to the axial direction, from the radially innermost position toward the radially outer side, there is a portion where the circumferential width of the wedge member 50 is constant, and the circumferential width of the wedge member 50 gradually increases from a predetermined radial position toward the radially outer side. The wedge-member-side protrusion 50a that protrudes in the circumferential direction is formed at the radially outermost position.

[0019] The wedge member side protrusions 50a overlap with the tooth side protrusions 20a in the circumferential direction. That is, the circumferential tip of the wedge member side protrusions 50a is located radially inward of the circumferential tip of the tooth side protrusions 20a, and they partially overlap in the circumferential direction. In this embodiment, both circumferential ends of the insulating member 70 are sandwiched between the wedge member side protrusions 50a and the tooth side protrusions 20a. In FIG. 3B, the portion of the insulating member 70 sandwiched between the wedge member side protrusions 50a and the tooth side protrusions 20a is shown as portion P.

[0020] An end plate 60 is attached to each of the axial ends of the rotor core 10 (see FIG. 2). FIGS. 4A and 4B are perspective views showing the end plate 60. The end plate 60 is shaped to contact the end face of the rotor core 10 at both axial ends of the rotor core 10. Specifically, the end plate 60 has a protrusion 62 that protrudes radially outward from an annular portion 61. The annular portion 61 forms a ring with approximately the same diameter as the annular portion of the axial end face of the rotor core 10 excluding the teeth 20.

[0021] Protrusions 62 are formed from the annular portion 61 toward the radially outward direction so as to be positioned corresponding to the teeth 20. That is, the end faces of the protrusions 62 on the rotor core 10 side are in contact with the axial end faces of the teeth 20, and the circumferential and radial shapes of the end faces are substantially identical between the protrusions 62 and the teeth 20. That is, the protrusions 62 extend radially outward from the annular portion 61 and include protrusions 62a that protrude circumferentially at the outermost radial position. The shape of the protrusions 62a corresponds to the tooth-side protrusions 20a of the teeth 20, and the end faces where the tooth-side protrusions 20a and the protrusions 62a are in contact have substantially the same shape (in this example, the protrusions 62a are slightly smaller).

[0022] As described above, the end plate 60 includes the annular portion 61 and the protruding portion 62, and is configured to cover the axial end face of the rotor core 10. The protruding portion 62 is the portion around which the coil end portion of the field winding 40 is wound. The end plate 60 is made of an insulating material, such as resin, and the presence of the end plate 60 between the coil end portion of the field winding 40 and the teeth 20 of the rotor core 10 prevents electrical conduction between the field winding 40 and the rotor core 10.

[0023] (2) Cooling configuration: Current flows through the field winding 40 of the rotor 1 during use of the motor, generating heat. For this reason, the rotor 1 is equipped with a configuration for cooling the field winding 40 with a coolant. FIG. 5 is a cross-sectional view showing the rotor core 10 cut along a plane parallel to the axial direction. FIG. 6 is a cross-sectional view showing the end plate 60 as viewed from the rotor core 10 side, with the end plate 60 and shaft 2 cut along line AA shown in FIG. 5. Note that the field winding 40, wedge members 50, and insulating members 70 are omitted from FIG. 6. FIG. 5 is also a cross-sectional view showing the state cut along line BB shown in FIG. 5. That is, FIG. 5 shows multiple cross sections cut at different positions in a single view.

[0024] As shown in Figures 5 and 6, a shaft 2 is attached to the radially inner side of the rotor core 10. The shaft 2 has a cylindrical hollow portion 2a that includes the rotation axis Ax, and is configured so that a coolant is pressure-fed to the hollow portion 2a through a cylindrical portion 3 inserted into the hollow portion 2a. The shaft 2 is formed with coolant supply portions 2b, which are multiple holes extending in a direction parallel to the radial direction. In this embodiment, four coolant supply portions 2b are formed at positions corresponding to both axial ends of the rotor core 10. The coolant supply portions 2b are arranged evenly in the circumferential direction, and the angle between adjacent coolant supply portions 2b in the circumferential direction in the cross section shown in Figure 5 is 90 degrees, measured around the rotation axis Ax.

[0025] The coolant supply portion 2b is a through hole that penetrates between an opening that opens to the hollow portion 2a and an opening that opens to the radially outer side of the shaft 2. In this embodiment, the axial position at which the coolant supply portion 2b is formed is adjusted so that the radially outer opening of the coolant supply portion 2b opens to the axial end face where the end plate 60 and the rotor core 10 are in contact.

[0026] In this embodiment, grooves 61a are formed in the end plates 60 at the end faces where the end plates 60 and the rotor core 10 meet. Specifically, the axial end faces of the rotor core 10 are configured with planes perpendicular to the axial direction. The axial end faces of the end plates 60 also include planes perpendicular to the axial direction. When the rotor 1 is manufactured, the end plates 60 are arranged so that the planes that form the axial end faces of the rotor core 10 and the planes that form the axial end faces of the end plates 60 meet.

[0027] A groove 61a extending in a direction parallel to the radial direction is formed in a plane constituting the axial end face of the end plate 60. The groove 61a is formed between the protrusions 62 in the circumferential direction and opens to a central portion between the protrusions 62. In this embodiment, an annular cavity 63 is formed radially inside the groove 61a. That is, a cavity is formed radially inside the groove 61a over the entire circumferential direction (see FIGS. 4B and 6). In this embodiment, the annular cavity 63 is a two-stage cavity with different axial sizes. That is, a first cavity 63a having a larger axial size is formed radially inside, and a second cavity 63b having a smaller axial size is formed adjacent to the radially outside of the first cavity 63a.

[0028] The radially inner side of the groove 61a opens into the hollow portion 63. Therefore, the groove 61a is a groove that extends in a direction parallel to the radial direction. In this embodiment, the groove 61a is formed between adjacent protrusions 62. That is, eight grooves 61a are formed at the axial end of the end plate 60. The grooves 61a are also evenly arranged in the circumferential direction, and the angle between adjacent grooves 61a in the circumferential direction in the cross section shown in FIG. 5 is 45 degrees, measured around the rotation axis Ax.

[0029] In this embodiment, the direction in which the grooves 61a extend is different from the direction in which the coolant supply portions 2b extend. Specifically, the grooves 61a are formed between the protruding portions 62 in the circumferential direction, but the coolant supply portions 2b are configured so that an extension line of the coolant supply portions 2b points to the center of the protruding portions 62 in the circumferential direction.

[0030] When the end plate 60 and the rotor core 10 are in contact with each other, the rotor core 10 side of the groove 61a is blocked by the end face of the rotor core 10. Therefore, the inner wall of the groove 61a and the end face of the rotor core 10 form a hole that penetrates from the opening on the radially inner side of the rotor core 10 to the opening on the radially outer side of the rotor core 10. That is, a portion of the inner wall of the hole is formed by the groove 61a formed in the end plate 60, and the remaining portion of the inner wall of the hole is formed by the axial end face of the rotor core 10. With the above configuration, in this embodiment, a hole is formed at the contact surface between the end plate 60 and the rotor core 10.

[0031] In the above configuration, the coolant supply portion 2b is located radially inside the rotor core 10. Therefore, when the rotor 1 rotates, centrifugal force causes the coolant accumulated in the cavity portion 2a to pass through the coolant supply portion 2b and be supplied to the first cavity portion 63a. At the radially outward extension of the coolant supply portion 2b, there is no groove 61a but a protrusion 62. Therefore, the coolant supplied from the coolant supply portion 2b to the first cavity portion 63a by centrifugal force does not directly enter the hole formed by the groove 61a.

[0032] The coolant supplied from the coolant supply unit 2b to the first cavity 63a accumulates in the first cavity 63a and the second cavity 63b, but moves circumferentially within the first cavity 63a and the second cavity 63b as the rotor 1 rotates. As a result, the coolant supplied from the coolant supply units 2b formed at four locations in the cross section shown in Figure 6 is present throughout the entire circumferential area of ​​the cavity 63.

[0033] Furthermore, when centrifugal force acts on the coolant in the cavity 63 due to the rotation of the rotor 1, the coolant moves radially outward through the holes formed by the eight grooves 61a. As shown in Figures 4B and 6, the grooves 61a are formed in the centers between the circumferentially adjacent protrusions 62. Therefore, the radially outer openings of the holes formed by the grooves 61a are open toward the slots 30 of the rotor core 10.

[0034] In this embodiment, as described above, the insulating member 70 is disposed along the wall surface 30a of the slot 30. Furthermore, as shown in Fig. 5 , the insulating member 70 is axially longer than the rotor core 10, and the axial end of the insulating member 70 is located closer to the end plate 60 than the axial end of the rotor core 10.

[0035] 7A and 7B are perspective views showing the rotor 1 with the axial direction oriented vertically. The field winding 40 is omitted in FIGS. 7A and 7B. Also, FIG. 7A includes an insulating member 70, while FIG. 7B does not. As shown in FIG. 7A, when the insulating member 70 is present, the opening 61a1 of the hole formed by the groove 61a is not exposed. On the other hand, as shown in FIG. 7B, when the insulating member 70 is not present, the opening 61a1 is exposed.

[0036] Because the insulating member 70 is axially longer than the position where the opening 61a1 is located, when the insulating member 70 is present, the opening 61a1 is located radially inward of the insulating member 70, as shown in FIG. 7A. Therefore, on the radially outer side, the coolant discharged from the hole formed by the groove 61a is supplied between the insulating member 70 and the wall surface 30a of the slot 30. In this embodiment, the portion of the end plate 60 where the groove 61a is formed is called a supply portion 61b (see FIG. 4B).

[0037] According to the above configuration, the rotation of the rotor 1 causes the coolant to be supplied between the insulating member 70 and the wall surface 30a of the slot 30. In this embodiment, the insulating member 70 is disposed along the wall surface 30a of the slot 30, and therefore the coolant supplied between the insulating member 70 and the wall surface 30a of the slot 30 moves radially outward between the insulating member 70 and the wall surface 30a of the slot 30 due to centrifugal force generated by the rotation of the rotor 1. In FIG. 3B , the direction of movement of the coolant through the gap existing between the insulating member 70 and the wall surface 30a of the slot 30 is indicated by a dashed arrow near the wall surface 30a.

[0038] In this way, the coolant moves between the insulating member 70 and the wall surface 30a of the slot 30, and the coolant is supplied to the entire gap between the insulating member 70 and the wall surface 30a of the slot 30. Therefore, the coolant can cool a wide area of ​​the field winding 40 via the insulating member 70, and the coil can be cooled highly efficiently with a simple configuration.

[0039] Furthermore, the coolant between the insulating member 70 and the wall surface 30a of the slot 30 can also move in the axial direction. Figure 5 is a cross-sectional view of the rotor core 10 cut along a plane that passes through the circumferential center of the wedge member 50 and is parallel to the axial direction. Therefore, the radially outer surface of the rotor core 10 that appears in Figure 5 is the wall surface 30a of the slot 30. As shown in Figure 5, the radially inner surface of the wedge member 50 is located radially outward of the wall surface 30a. For this reason, a gap may exist between the wall surface 30a and the wedge member 50.

[0040] In this embodiment, an insulating member 70 is disposed in this gap. The insulating member 70 has a curved shape in the cross section shown in FIG. 5. Specifically, the axial ends of the insulating member 70 are in contact with the end plate 60, and the closer to the axial center, the farther the insulating member 70 is from the end plate 60 and the wall surface 30a. Therefore, the gap Gp between the wall surface 30a of the slot 30 and the insulating member 70 becomes larger from the axial ends toward the axial center.

[0041] In this embodiment, the grooves 61a are formed on the axial end surfaces where the end plates 60 and the rotor core 10 are in contact. Therefore, the gap Gp at the position of the openings 61a1 of the holes formed by the grooves 61a is narrower than the gap Gp at the axial center, and the gap Gp becomes wider as it approaches the axial center. Therefore, the coolant supplied to the gap Gp through the holes formed by the grooves 61a tends to flow toward the axial center along the insulating member 70 in the axial direction. With the above configuration, the coolant is supplied over the entire axial area. Therefore, the coolant can cool a wide area of ​​the field winding 40 via the insulating member 70, and the coil can be cooled highly efficiently with a simple configuration.

[0042] The gap Gp between the insulating member 70 and the wall surface 30a of the slot 30 may be adjusted so that the coolant supplied through the opening 61a1 can easily move to other positions in the axial direction. Therefore, it is sufficient that the gap Gp is ​​narrow near the opening 61a1 and wide at other positions in the axial direction. The configuration for adjusting the gap Gp is ​​not limited to adjustment by the shape of the insulating member 70 as shown in FIG. 5 . For example, a configuration such as providing a protrusion protruding radially may be used. In the example shown in FIG. 5 , a protrusion protruding radially inward may be provided at the axial end of the wedge member 50, and the end of the insulating member 70 may be sandwiched between the protrusion and the end plate 60. This configuration allows the insulating member 70 to be closer to the end plate 60 at the axial end and to be farther away from the wall surface 30a at the axial center, thereby relatively increasing the gap Gp.

[0043] Note that the radial size of the gap Gp is ​​exaggerated in Figure 5. Therefore, the radial size of the gap Gp may be smaller. Of course, the radial size of the gap Gp may be the length shown in Figure 5. In this case, the radial length of the wedge member 50 shown in Figure 3A will be shorter than the length shown in the figure.

[0044] Furthermore, in this embodiment, grooves 61a are formed in the axial end surfaces of the end plates 60, and holes that serve as coolant passages are formed by the grooves 61a and the flat surfaces that form the end surfaces of the rotor core 10. Therefore, the end surfaces of the rotor core 10 are formed as flat surfaces with simple shapes. For this reason, it is possible to supply coolant between the wall surfaces 30a of the slots 30 and the insulating members 70 with a simple configuration, without complicating the shape of the rotor core 10.

[0045] 3B , in this embodiment, both circumferential ends of the insulating member 70 are sandwiched between the wedge member-side protrusion 50a and the tooth-side protrusion 20a at portion P. Therefore, even if the coolant flows between the wall surface 30a of the slot 30 and the insulating member 70 as shown by the dashed arrow and reaches portion P, there is no gap between the wall surface 30a of the slot 30 and the insulating member 70 at portion P.

[0046] For this reason, the coolant is not discharged (or is hardly discharged) outside of the portion P in the circumferential and radial directions. Therefore, the only room for the coolant that reaches the portion P to move is in the axial direction, and the coolant is discharged outside the rotor 1 from both ends in the axial direction. Figure 1 shows two portions Pe from which the coolant can be discharged. The coolant is not discharged (or is hardly discharged) from the area sandwiched between the portions Pe at both ends in the axial direction. In Figure 1, an example of a portion from which the coolant is not discharged is shown as portion Pn.

[0047] In the axial direction, the coolant is not discharged from the area sandwiched between the end portions Pe, which prevents the drag resistance between the stator and the rotor core 10 from increasing. That is, the axial length of the stator and the axial length of the rotor core 10 are substantially the same, and the positions of both ends of the stator in the axial direction and the positions of both ends of the rotor core 10 in the axial direction are substantially the same. Therefore, for example, when the coolant is discharged from the portion Pn, the coolant comes into contact with both the stator and the rotor 1 located near the portion Pn, and drag resistance occurs when the rotor 1 rotates. The drag resistance increases as the amount of coolant present between the stator and the rotor 1 increases.

[0048] However, in this embodiment, the coolant is not discharged from the portion Pn but is discharged from the portion Pe, so there is no or very little drag resistance due to the coolant between the stator and the rotor 1. Therefore, the rotor 1 according to this embodiment can provide a high-torque motor.

[0049] (3) Other embodiments: The above embodiment is one example for carrying out the present invention, and various other embodiments are possible. For example, the shapes and numbers of the slots 30, field windings 40, wedge members 50, end plates 60, and insulating members 70 are not limited to those in the above embodiment, and various configurations are possible. A configuration in which the above-mentioned members are integrated, or a configuration in which they are separated into more members, may also be used. For example, a configuration in which the end plates 60 and insulating members 70 are integrated may also be used.

[0050] The rotor core may be an annular member having a plurality of teeth protruding radially outward and arranged circumferentially, and slots formed between the teeth in the circumferential direction. That is, the rotor core may have a plurality of teeth around which coils are wound, and may be configured so that the rotor core can rotate relative to the stator due to the interaction between the magnetic field generated by the coils and the magnetic field generated by the stator. The rotor core may have various configurations, such as the number of magnetic poles and the number of slots, and materials. Furthermore, the rotor core may be rotatable around the rotor shaft disposed radially inward, and the rotor shaft may also be configured with no restrictions on its shape, material, etc.

[0051] The rotor core may be annular as a whole. The shapes of the radially inner and outer surfaces of the ring formed by the rotor core are not limited. For example, the radially inner surface may be circular when viewed from the axial direction, or may have a polygonal shape. Teeth are formed on the radially outer surface, and slots are formed between the teeth. In the rotor core, the general shape including the teeth can be considered annular, and the portion excluding the teeth can also be considered annular.

[0052] The field windings may be either square or round wire as long as they are wound around the teeth, and there are no limitations on the shape of the wire itself, nor on the number of turns or winding method.

[0053] The insulating member may be disposed between the slot wall surface and the field winding so as to follow the slot wall surface. In other words, the insulating member may be disposed between the slot wall surface and the field winding over the entire surface of the slot wall surface, insulating the coil from the rotor core. The insulating member may be made of any material or thickness as long as it can insulate the coil from the rotor core. For example, the insulating member may be made of various types of paper or resin. The thickness is not limited, but in order to be disposed along the slot wall surface, it is preferable that the insulating member has a thickness that allows it to deform to conform to the shape of the wall surface. The thickness of such an insulating member is typically thinner than that of the wedge member.

[0054] The supply portion only needs to have a hole for supplying coolant between the insulating member and the wall surface of the slot from the radially inner side of the rotor core. In other words, the supply portion only needs to be able to supply coolant between the insulating member and the wall surface of the slot through the hole provided in the supply portion. When coolant is supplied between the insulating member and the wall surface of the slot, the coil in contact with the insulating member can be cooled by the coolant. Because the insulating member is arranged along the wall surface of the slot, the coolant can be supplied along the wall surface of the slot. Therefore, the entire wall surface of the slot functions as a surface capable of cooling the coil.

[0055] The holes are formed to supply coolant between the insulating members and the slots from the radially inner side of the rotor core. For example, the holes are configured as through-holes connecting the radially inner space of the rotor core with the wall surfaces of the slots. The holes may be configured so that coolant flows from the radially inner side to the radially outer side as the rotor rotates, and is supplied between the insulating members and the slots. For example, such holes may be holes that extend linearly in a direction parallel to the radial direction, but the direction and shape of the holes are not limited as long as the coolant can be supplied between the insulating members and the slots.

[0056] The hole only needs to be included in the supply portion, and the supply portion may be formed of one member or two or more members. The supply portion only needs to be a portion that forms a through-hole that moves the coolant present on the radially inner side of the rotor core radially and supplies the coolant between the insulating member and the wall surface of the slot. The hole included in the supply portion may be located at any axial position within the range in which the insulating member is present in the axial direction. Therefore, for example, the end plate 60 may constitute the supply portion, and a hole penetrating the end plate 60 may be formed. Alternatively, the supply portion may be part of the rotor core 10, and the hole may be formed by a groove formed in the rotor core 10 and the end surface of the end plate 60. Alternatively, the rotor core 10 may constitute the supply portion, and a hole penetrating the rotor core 10 may be formed. Furthermore, spacers or the like may be disposed between the electromagnetic steel sheets that constitute the rotor core 10, and holes may be formed between the spacers and the electromagnetic steel sheets by holes penetrating the spacers or grooves formed in the spacers.

[0057] The coolant may be supplied from the radially inner side of the rotor core through the holes between the insulating members and the wall surfaces of the slots, and various methods may be used to supply the coolant to the holes in the rotor core. In the above-described embodiment, a coolant passage is formed inside the shaft, and the coolant is supplied from the passage to the holes in the supply portion through holes extending to the radially inner surface of the rotor core, but this configuration is not limited to this. For example, the configuration for moving the coolant between the inside of the shaft and the holes in the supply portion is not limited to holes, and the coolant may be moved by a larger cavity or the like, or various other configurations may be used. [Explanation of symbols]

[0058] REFERENCE SIGNS LIST 1...rotor, 2...shaft, 2a...hollow portion, 2b...coolant supply portion, 3...cylindrical portion, 10...rotor core, 20...teeth, 20a...teeth-side protrusion, 30...slot, 30a...wall surface, 40...field winding, 50...wedge member, 50a...wedge-member-side protrusion, 60...end plate, 61...annular portion, 61a...groove, 61a1...opening, 61b...supply portion, 62...protrusion, 62a...protrusion, 63...hollow portion, 63a...first hollow portion, 63b...second hollow portion, 70...insulating member

Claims

1. an annular rotor core having a plurality of teeth that protrude radially outward and are arranged in a circumferential direction, and slots that are formed between the teeth in the circumferential direction; a field winding wound around the teeth; an insulating member disposed between the wall surface of the slot and the field winding so as to follow the wall surface of the slot; a supply portion having a hole for supplying a coolant between the insulating member and a wall surface of the slot from a radially inner side of the rotor core; A rotor comprising:

2. end plates contacting end faces of the rotor core at both axial ends, The supply unit includes: The holes are formed in the contact surfaces between the end plates and the rotor core, a gap between the wall surface of the slot and the insulating member becomes larger from the axial end portion toward the axial center; The rotor of claim 1 .

3. the supply portion is a part of the end plate, At least a portion of the hole is defined by the end plate. The rotor of claim 2 .

4. a wedge member that fills a circumferential gap formed between the field windings wound around adjacent teeth and has a wedge member-side protrusion that protrudes in the circumferential direction on a radially outer side, The teeth each include a tooth-side protrusion that protrudes in a circumferential direction from a radially outer side thereof, Both circumferential ends of the insulating member are sandwiched between the wedge member-side protruding portion and the tooth-side protruding portion. The rotor according to claim 1 or 2.

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