Rotor

Abstract

To provide a rotor that suppresses the occurrence of cracks in the resin on the end face of the magnet. [Solution] The rotor R of this disclosure comprises a rotor core 10 having a first magnet hole 11 for housing a first magnet MG1, a first rotor core sheet 20 having an opening 21 that contacts the axial end face of the first magnet MG1 and partially overlaps the arrangement region S1 of the first magnet hole 11 where the first magnet MG1 is placed, and a resin portion provided between the first magnet MG1 and the first magnet hole 11 and within the opening 21, wherein the opening 21 is not provided in a position that overlaps the side portion MS of the first magnet MG1 along the orientation direction of the first magnet MG1. Furthermore, the first magnet hole 11 has a first region S2 that does not house the first magnet MG1 and is provided adjacent to the arrangement region S1 where the first magnet MG1 is placed, and the opening 21 has a first overlapping portion 22 that overlaps the first region S2, and the first overlapping portion 22 is provided in the orientation direction of the first magnet MG1.

Description

[Technical Field]

[0001] The present disclosure relates to a rotor. [Background Art]

[0002] Patent Document 1 discloses a rotor including: a core body having a through hole opening to a surface formed therein; a magnet housed in the through hole, both end faces of the magnet arranged in the extending direction of the through hole being positioned closer to an inner side of the through hole than an opening of the through hole; and an insulating material filled into the through hole so as to cover both end faces of the magnet, wherein the core body includes a support portion formed on an inner surface of the core body defining the through hole and configured to support the magnet.

[0003] Specifically, the core body is formed by laminating a plurality of electromagnetic steel sheets, and an electromagnetic steel sheet positioned at an end on one side, the electromagnetic steel sheet having an opening formed with a protruding portion that supports an end face of the magnet, is used.

[0004] Then, with the core body arranged with one side facing downward, and the lower end face of the magnet housed in the through hole being supported by the protruding portion, a resin serving as an insulating material is poured into the through hole from an upper side of the core body, and the resin also flows into the opening where the protruding portion is formed, whereby the opening is blocked by the resin and the magnet is prevented from contacting the outside air. [Prior Art Documents] [Patent Documents]

[0005] [Patent Document 1] Japanese Unexamined Patent Publication No. 2008-109777 [Summary of the Invention] [Problem to be Solved by the Invention]

[0006] On the other hand, anisotropic magnets are often used for magnets used in motors and the like. For an anisotropic magnet, the orientation direction has a positive linear expansion coefficient, and a direction orthogonal to the orientation direction has a negative linear expansion coefficient.

[0007] Furthermore, in Patent Document 1, an opening formed in an electromagnetic steel sheet located at one end of the core body, which supports the end face of a magnet, straddles the end of the magnet (hereinafter also simply referred to as the end of the magnet) in a direction perpendicular to the orientation direction.

[0008] Therefore, during the cooling process after the resin is poured, the magnet expands in a direction perpendicular to its orientation, while the resin inside the opening attempts to contract. However, as mentioned above, since the electromagnetic steel sheet containing the opening is located on the lower side, the resin inside the opening cannot flow in a way that follows the expansion of the magnet.

[0009] As a result, at the point where the magnet's edge crosses the opening, the magnet's edge expands, applying stress in the opposite direction to the shrinking resin within the opening, which may cause cracks to form in the resin.

[0010] This disclosure has been made in view of these circumstances, and one of its objectives is to provide a rotor that suppresses the occurrence of resin cracks on the end face of the magnet. [Means for solving the problem]

[0011] The rotor of this disclosure is A rotor core having a first magnet hole for housing a first magnet, A first rotor core sheet having an opening that contacts the axial end face of the first magnet and partially overlaps the arrangement area of ​​the first magnet hole where the first magnet is placed, The structure comprises the space between the first magnet and the first magnet hole, and a resin portion provided within the opening, The opening is not located in a position that overlaps with the side of the first magnet along the orientation direction of the first magnet. [Effects of the Invention]

[0012] According to this disclosure, a rotor is provided that suppresses the occurrence of cracks in the resin on the end face of the magnet. [Brief explanation of the drawing]

[0013] [Figure 1] It is a side view of the rotor according to the first embodiment of the present disclosure. [Figure 2] It is a front view of the rotor according to the first embodiment of the present disclosure viewed from one axial side. [Figure 3] It is a front view of the rotor core according to the first embodiment of the present disclosure viewed from one axial side. [Figure 4] It is a front view of the first rotor core sheet according to the first embodiment of the present disclosure viewed from one axial side. [Figure 5] It is a diagram for explaining the first magnet hole according to the first embodiment of the present disclosure, the positional relationship between the second magnet hole and the opening, and the like. [Figure 6] It is a diagram for explaining the first magnet hole according to the first embodiment of the present disclosure, the step of filling resin into the opening, and the cooling step. [Figure 7] It is an enlarged cross-sectional view enlarging the periphery of the first overlapping portion in FIG. 6. [Figure 8] It is a side view of the rotor according to the second embodiment of the present disclosure. [Figure 9] It is a cross-sectional view of the rotor core, the first rotor core sheet, and the second rotor core sheet according to the second embodiment of the present disclosure. DETAILED DESCRIPTION OF EMBODIMENTS

[0014] Hereinafter, modes for carrying out the present disclosure (hereinafter referred to as "embodiments") will be described in detail with reference to the accompanying drawings. Note that the same numbers or reference signs are assigned to the same elements throughout the entire description of the embodiments.

[0015] In addition, the dimensional ratios in the drawings differ from the actual dimensional ratios, and are merely drawn to facilitate understanding of the description, and do not guarantee that the same portions are drawn with the same dimensions between the drawings.

[0016] Furthermore, in the drawings, for the sake of visibility, reference signs may only be partially assigned to a plurality of portions having the same attribute.

[0017] <<First Embodiment>> A rotor R according to a first embodiment of the present disclosure will be described with reference to FIGS. 1 to 7.

[0018] FIG. 1 is a side view of the rotor R according to the first embodiment of the present disclosure, which is a view of the longitudinal direction (Z direction) of a rotor shaft S as viewed from the front.

[0019] FIG. 2 is a front view of the rotor R according to the first embodiment of the present disclosure as viewed from one axial side. Note that in FIG. 2, illustration of a first rotor core sheet 20 provided on one end face of a rotor core 10 is omitted.

[0020] FIG. 3 is a front view of the rotor core 10 of the rotor R according to the first embodiment of the present disclosure as viewed from one axial side.

[0021] FIG. 4 is a front view of the first rotor core sheet 20 according to the first embodiment of the present disclosure as viewed from one axial side. Note that in FIG. 4, the positions where a first magnet MG1 and a second magnet MG2 are arranged are also shown so that the positional relationship between the first magnet MG1 arranged on the back side (the other side) of the first rotor core sheet 20 and the second magnet MG2 can be understood.

[0022] Hereinafter, the longitudinal direction (Z direction) of the rotor shaft S serving as a rotation shaft is referred to as the axial direction, the direction along the rotation direction of the rotor shaft S is referred to as the circumferential direction, and the direction on a plane (XY plane) orthogonal to the axial direction is referred to as the radial direction.

[0023] In the radial direction, the side away from the rotor shaft S is referred to as a radially outer side, and conversely, the side close to the rotor shaft S is referred to as a radially inner side.

[0024] For example, the rotor R can be suitably used for motors (also referred to as rotating electric machines) used in hybrid vehicles, electric vehicles, and the like.

[0025] Specifically, the motor (not shown) comprises a rotor R of the first embodiment (see Figure 1), a stator (not shown) provided radially outside the rotor R and surrounding the rotor core RCP, and a case (not shown) that houses the rotor R and the stator, and also houses a refrigerant (for example, an oil such as ATF) for cooling the rotor R and the stator.

[0026] In other words, the rotor R of the first embodiment is a rotor R used in an inner rotor type motor (not shown).

[0027] As shown in Figure 1, the rotor R comprises a rotor shaft S and an annular rotor core RCP provided on the outer circumference of the rotor shaft S.

[0028] Furthermore, as shown in Figure 2, the rotor R is equipped with magnets (first magnet MG1 and second magnet MG2) provided for each magnetic pole (region between adjacent q axes).

[0029] [Rotor Shaft S] As shown in Figure 2, the rotor shaft S of the first embodiment is a hollow cylindrical member, and a refrigerant can be flowed through the rotor shaft S. However, the rotor shaft S may be a cylindrical member that is not hollow inside.

[0030] [Rotor core section RCP] As shown in Figure 1, the rotor core section RCP comprises a rotor core 10 and a pair of first rotor core seats 20 provided at both ends of the rotor core 10 in the axial direction (Z direction).

[0031] (Rotor Core 10) In the first embodiment, as shown in Figure 1, the rotor core 10 is formed by stacking a plurality of electromagnetic steel sheets in the axial direction (Z direction), but the rotor core 10 may also be a compacted core made by press-forming metal powder or the like.

[0032] As shown in Figure 3, the rotor core 10 is a cylindrical member having a circular through-hole SH in the center through which the rotor shaft S is positioned.

[0033] The rotor core 10 has a plurality of first magnet holes 11 for housing the first magnet MG1 (see Figure 2) and a plurality of second magnet holes 12 for housing the second magnet MG2 (see Figure 2).

[0034] In the first embodiment, four first magnet holes 11 are provided for each magnetic pole (the region between adjacent q axes).

[0035] Specifically, there are four first magnet holes 11, one for each magnetic pole (in the region between adjacent q axes): a pair of first outer magnet holes 11A arranged symmetrically on the radially outward side with the d axis in between to accommodate the first magnet MG1 (see Figure 2), and a pair of first inner magnet holes 11B arranged symmetrically on the radially inward side with the d axis in between to accommodate the first magnet MG1.

[0036] The first magnet hole 11 (first outer magnet hole 11A and first inner magnet hole 11B) has a placement area S1 in which the first magnet MG1 (see Figure 2) is placed, and a first area S2 adjacent to the placement area S1 that does not house the first magnet MG1.

[0037] The first region S2 is provided adjacent to the placement region S1, where the first magnet MG1 (see Figure 2) is placed, in a direction perpendicular to the orientation direction of the first magnet MG1.

[0038] In the first embodiment, the pair of first outer magnet holes 11A are arranged to form a V-shape in which the arrangement region S1 for arranging the first magnet MG1 (see Figure 2) opens radially outward.

[0039] However, the design is not limited to this, and the pair of first outer magnet holes 11A may also be arranged such that the arrangement region S1 for positioning the first magnet MG1 is provided in a straight line along a direction perpendicular to the d-axis.

[0040] Furthermore, in the first embodiment, the pair of first inner magnet holes 11B are arranged to form a V-shape in which the arrangement region S1 for arranging the first magnet MG1 (see Figure 2) opens radially inward.

[0041] However, the design is not limited to this, and the pair of first inner magnet holes 11B may also be arranged such that the arrangement region S1 for positioning the first magnet MG1 is provided in a straight line along a direction perpendicular to the d-axis.

[0042] Alternatively, either the pair of first outer magnet holes 11A or the pair of first inner magnet holes 11B may be omitted, and two first magnet holes 11 may be provided for each magnetic pole (in the region between adjacent q-axes).

[0043] On the other hand, in the first embodiment, two second magnet holes 12 are provided for each magnetic pole (the region between adjacent q axes).

[0044] Specifically, a pair of second magnet holes 12 are provided symmetrically across the d-axis, circumferentially outward from the first magnet hole 11, for each magnetic pole (in the region between adjacent q-axes).

[0045] The second magnet hole 12 has a placement area S3 for arranging the second magnet MG2 (see Figure 2), and a second area S4 adjacent to the placement area S3 that does not accommodate the second magnet MG2.

[0046] The second region S4 is provided adjacent to the placement region S3 where the second magnet MG2 (see Figure 2) is placed, in a direction perpendicular to the orientation direction of the second magnet MG2 to be placed.

[0047] Furthermore, in the first embodiment, the pair of second magnet holes 12 are arranged to form a V-shape in which the arrangement region S3 for arranging the second magnet MG2 (see Figure 2) opens radially outward.

[0048] (First rotor core sheet 20) The first rotor core sheet 20 is provided at both ends of the rotor core 10 in the axial direction, and the first rotor core sheet 20 provided at least on one side in the axial direction (Z direction) of the rotor core 10 is in contact with one axial end face of the first magnet MG1 and the second magnet MG2.

[0049] Alternatively, the first rotor core sheet 20 provided on one side of the rotor core 10 in the axial direction (Z direction) may contact one axial end face of the first magnet MG1 and the second magnet MG2, while the first rotor core sheet 20 provided on the other side of the rotor core 10 in the axial direction (Z direction) may contact the other axial end face of the first magnet MG1 and the second magnet MG2.

[0050] Furthermore, the first rotor core seat 20, which is provided on the other side of the rotor core 10 in the axial direction (Z direction), may be omitted.

[0051] As shown in Figure 4, the first rotor core sheet 20 is a disc-shaped member having a circular opening SO in the center through which the rotor shaft S passes. Furthermore, the first rotor core sheet 20 is made of electrical steel sheet or the like.

[0052] The first rotor core sheet 20 is provided corresponding to each first magnet hole 11 (see Figure 3) and has multiple openings 21 that partially overlap the corresponding first magnet MG1. In other words, the first rotor core sheet 20 is provided corresponding to the first magnet hole 11 and has an opening 21 that partially overlaps with the arrangement area S1 in which the first magnet MG1 of the first magnet hole 11 is placed.

[0053] As will be explained later, in the first embodiment, when viewed in a cross-section perpendicular to the longitudinal direction of the first magnet MG1, the short side direction is the orientation direction, and the long side direction is perpendicular to the orientation direction.

[0054] Therefore, as can be seen in Figure 4, the opening 21 is provided on the first rotor core sheet 20 so as not to overlap with the side MS of the first magnet MG1 (the short side of the axial end face of the first magnet MG1) on the side perpendicular to the orientation direction of the first magnet MG1.

[0055] In other words, the opening 21 is not located in a position that coincides with the side MS of the first magnet MG1 (in this example, the short side of the axial end face of the first magnet MG1) along the orientation direction of the first magnet MG1.

[0056] In the first embodiment, an opening 21 is provided corresponding to each of the first magnet holes 11 (see Figure 3) that house the first magnet MG1, and the first rotor core sheet 20 has four openings 21 for each magnetic pole (region between adjacent q axes).

[0057] Specifically, four openings 21 are provided for each magnetic pole (in the region between adjacent q axes): a pair of outer openings 21A corresponding to a pair of first outer magnetic holes 11A (see Figure 3) which are provided radially outward and symmetrically on the d axis, and a pair of inner openings 21B corresponding to a pair of first inner magnetic holes 11B (see Figure 3) which are provided radially inward and symmetrically on the d axis, and these four openings 21 are provided for each magnetic pole (in the region between adjacent q axes).

[0058] (First magnet MG1, and second magnet MG2) The first magnet MG1 and the second magnet MG2 both use the same magnet, and in the first embodiment, the first magnet MG1 and the second magnet MG2 are neodymium magnets (Nd magnets) with their crystal easy magnetization axes oriented in one direction.

[0059] Furthermore, anisotropic magnets other than neodymium magnets may be used for the first magnet MG1 and the second magnet MG2. Furthermore, the shapes of the first magnet MG1 and the second magnet MG2 may be different.

[0060] In the first embodiment, when viewed in a cross-section perpendicular to the longitudinal direction, the first magnet MG1 and the second magnet MG2 have their orientation direction in the short side direction and their orientation direction in the long side direction perpendicular to the orientation direction.

[0061] Therefore, during the cooling process after filling the first magnet hole 11 (see Figure 3) and the second magnet hole 12 (see Figure 3), which will be explained later, with resin, the first magnet MG1 and the second magnet MG2 contract in the direction of the shorter side, which is the orientation direction, and expand in the direction of the longer side, which is perpendicular to the orientation direction.

[0062] Depending on the design of the rotor R, a first magnet MG1 and a second magnet MG2 may be used, where the longer side is the orientation direction and the shorter side is perpendicular to the orientation direction.

[0063] Next, with reference to Figure 5, the positional relationship between the first magnet hole 11 (see Figure 3), the second magnet hole 12 (see Figure 3), and the opening 21 will be explained in detail.

[0064] Figure 5 is a diagram illustrating the positional relationship between the first magnet hole 11, the second magnet hole 12, and the opening 21 of the first embodiment of the present disclosure. It is an enlarged view of the area including the first magnet hole 11, the second magnet hole 12, and the opening 21, which are located within one magnetic pole (the region between adjacent q-axes) when the rotor core RCP is viewed from one side.

[0065] Note that the first magnet hole 11, the second magnet hole 12, and the magnets (first magnet MG1 and second magnet MG2) are located towards the back of the paper and are not normally visible, but in Figure 5 they are depicted in a way that makes their state clear.

[0066] As shown in Figure 5, the opening 21 of the first rotor core sheet 20 has a first overlapping portion 22 that overlaps the first region S2 of the first magnet hole 11 that does not contain the first magnet MG1.

[0067] Specifically, the opening 21, which has a portion that overlaps with the placement area S1 in which the first magnet MG1 of the first magnet hole 11 is placed, also includes a first overlapping portion 22 that overlaps with the first area S2 in which the first magnet MG1 of the first magnet hole 11 is not housed.

[0068] In other words, the opening 21 comprises a portion that overlaps with a part of the arrangement region S1 with respect to the corresponding first magnet hole 11, and a first overlapping portion 22 that overlaps with the first region S2.

[0069] The first overlapping portion 22 is provided in the orientation direction of the first magnet MG1 housed in the corresponding first magnet hole 11 (the first magnet hole 11 whose opening 21 overlaps the arrangement region S1).

[0070] More specifically, the first overlapping portion 22 is positioned further away from the first magnet MG1 in the orientation direction (the direction of the short side of the first magnet MG1) than the first magnet MG1 housed in the corresponding first magnet hole 11.

[0071] Furthermore, the position where the first overlapping portion 22 is provided is also a position away from the first magnet MG1 in a direction perpendicular to the orientation direction (the direction of the long side of the first magnet MG1) than the first magnet MG1 housed in the corresponding first magnet hole 11.

[0072] Figure 6 is a diagram illustrating the first magnet hole 11, the resin filling process into the opening 21, and the cooling process of the first embodiment according to the present disclosure. Figure 6 is a cross-sectional view of line AA in Figure 5, with the left side of Figure 6 being the A1 side and the right side being the A2 side.

[0073] As shown in Figure 6, before the other side's first rotor core sheet 20 is installed, the outer end face of one side's first rotor core sheet 20 is placed in close contact with the mounting section MP of the resin filling device, and resin is supplied to the first magnet hole 11 from the other side.

[0074] The supplied resin then flows into the opening 21 through the first overlapping section 22, filling the opening 21 with resin. This filled resin then solidifies during the cooling process, becoming the resin portion RP located between the first magnet MG1 and the first magnet hole 11, and within the opening 21.

[0075] Although the portion of the opening 21 that overlaps the first magnet MG1 appears not to be connected to the first overlapping portion 22 in the cross-sectional view shown in Figure 6, as shown in Figure 5, it is connected to the first overlapping portion 22 in a portion not shown in the cross-sectional view of Figure 6, and is filled with resin flowing into the opening 21 from the first overlapping portion 22.

[0076] Furthermore, the upper and lower edges of the first magnet MG1 shown in Figure 6 are the longer side of the longitudinal end face of the first magnet MG1 (the side perpendicular to the orientation direction of the first magnet MG1), and as explained earlier, they have a negative coefficient of linear expansion. On the other hand, resins have a positive coefficient of linear thermal expansion.

[0077] Therefore, during the cooling process after the filling process, the first magnet MG1 expands in the left-right direction in Figure 6, as indicated by the thick black arrows. On the other hand, the resin tends to shrink, as indicated by the dotted arrow.

[0078] As a result of this expansion and contraction, stress tends to concentrate in the portion P (the other side portion P1 and the one side portion P2) of the side MS (in this example, the short side of the longitudinal end face of the first magnet MG1) along the orientation direction of the first magnet MG1.

[0079] However, since the resin on the other side is in a free state, it flows in response to the stress that would otherwise concentrate on the other side portion P1, thus avoiding stress concentration and preventing the occurrence of cracks and the like.

[0080] On the other hand, the one-sided portion P2 does not have an opening 21 and is only in contact with the first rotor core seat 20, so there is no resin itself that can cause cracks, and therefore there is no risk of cracks occurring.

[0081] Furthermore, if the other side's first rotor core sheet 20 (not shown) is also in contact with the axial end face of the first magnet MG1, and resin is supplied to the opening 21 (not shown) of the other side's first rotor core sheet 20, and the resin is filled from the opening 21 of the other side's first rotor core sheet 20 into the first magnet hole 11 and the opening 21 of the first rotor core sheet 20 on one side, then the other side's first rotor core sheet 20 will be in the same condition as the first side's first rotor core sheet 20 shown in Figure 6, and therefore there is no risk of cracks occurring.

[0082] Thus, the rotor R of the first embodiment suppresses the occurrence of resin cracks on the end face of the first magnet MG1.

[0083] Furthermore, as explained earlier, the first overlapping portion 22 is provided in the orientation direction of the first magnet MG1 housed in the corresponding first magnet hole 11 (the first magnet hole 11 whose opening 21 overlaps the arrangement region S1), so it is not affected by the expansion of the first magnet MG1 during the cooling process, and there is no risk of cracks occurring.

[0084] By the way, in the first embodiment, as explained earlier, a portion of the opening 21 overlaps with the arrangement region S1 in which the first magnet MG1 of the first magnet hole 11 is placed. As shown in Figure 6, resin is provided on one axial end face of the first magnet MG1.

[0085] Therefore, the formation of magnetic paths is suppressed, and leakage flux is reduced, resulting in improved electromagnetic performance.

[0086] Figure 7 is an enlarged cross-sectional view showing the area around the first overlapping portion 22 in Figure 6. As shown in Figure 7, the first overlapping portion 22 has an opening area OS1 when viewed from the first region S2 side to the first overlapping portion 22 side, which is defined by the opening width W1 at the boundary between the first region S2 and the opening 21 and the depth width D1 along the first overlapping portion 22 (in the front-to-back direction of the paper in Figure 7).

[0087] Similarly, the first overlapping portion 22 has an opening area OS2 when viewed from the opening 21 side to the first overlapping portion 22 side, which is defined by the opening width W2 corresponding to the thickness of the opening 21 and the depth width D2 along the first overlapping portion 22 (in the front-to-back direction of the paper in Figure 7).

[0088] In the first embodiment, the opening area OS2 of the first overlapping portion 22 is larger when viewed from the opening 21 side to the first overlapping portion 22 side than when viewed from the first region S2 side to the first overlapping portion 22 side.

[0089] Thus, by making the opening area OS2 larger than the opening area OS1, the resin flowing from the first region S2 through the first overlapping portion 22 into the opening 21 will flow towards the side with the larger opening area. This suppresses obstruction of the resin flow and enables good resin filling into the opening 21.

[0090] Therefore, it is possible to thoroughly fill the resin up to the opening 21 and other locations on the first magnet MG1 shown in Figure 6, thereby suppressing the occurrence of areas that are not filled with resin and preventing the first magnet MG1 from being exposed to the outside air.

[0091] On the other hand, as shown in Figure 5, the opening 21 of the first rotor core sheet 20 has a second overlapping portion 23 that overlaps the second region S4 of the second magnet hole 12 that does not house the second magnet MG2.

[0092] Specifically, a pair of inner openings 21B corresponding to a pair of first inner magnet holes 11B among the openings 21 are provided with a second overlapping portion 23.

[0093] The second overlapping portion 23 is provided in the orientation direction of the second magnet MG2, which is housed in the corresponding second magnet hole 12 (the second magnet hole 12 in which the opening 21 overlaps with the second overlapping portion 23).

[0094] More specifically, the second overlapping portion 23 is positioned further away from the second magnet MG2 in the orientation direction (the direction of the short side of the second magnet MG2) than the second magnet MG2 housed in the corresponding second magnet hole 12.

[0095] Furthermore, the position where the second overlapping portion 23 is provided is also a position away from the second magnet MG2 in a direction perpendicular to the orientation direction (the direction of the long side of the second magnet MG2) than the second magnet MG2 housed in the corresponding second magnet hole 12.

[0096] Thus, the positional relationship of the second overlapping portion 23 with respect to the second magnet MG2 is the same as the positional relationship of the first magnet MG1 with respect to the first magnet MG1, as explained earlier. Since it is positioned in the orientation direction of the second magnet MG2 housed in the corresponding second magnet hole 12 (the second magnet hole 12 whose opening 21 overlaps with the second overlapping portion 23), it is not affected by the expansion of the second magnet MG2 during the cooling process, and there is no risk of cracks occurring.

[0097] By the way, in the first embodiment, the resin filling process is carried out by supplying resin to the first magnet hole 11 from the other side, as explained earlier.

[0098] As can be seen in Figure 5, the resin supplied to the first magnet hole 11 flows from the first magnet hole 11 through the first overlapping section 22 into the opening 21, and then the resin flows through the opening 21 toward the second overlapping section 23, and through the second overlapping section 23 into the second magnet hole 12, thereby filling it with resin. The resin, once filled in this manner, solidifies during the cooling process and becomes a resin portion RP (not shown) located between the second magnet MG2 and the second magnet hole 12.

[0099] However, the resin filling process does not need to be limited to supplying resin to the first magnet hole 11 from the other side; resin may also be supplied from the other side of the second magnet hole 12.

[0100] In such cases, it is preferable to improve the fluidity of the resin in the second overlapping portion 23 as well, similar to the first overlapping portion 22, by making the opening area of ​​the second overlapping portion 23 larger when viewed from the opening 21 side to the second overlapping portion 23 side than when viewed from the second region S4 side to the second overlapping portion 23 side.

[0101] <<Second Embodiment>> Next, the rotor R of the second embodiment of this disclosure will be described with reference to Figures 8 and 9.

[0102] The rotor R of the second embodiment has the same basic configuration as the rotor R of the first embodiment. Below, we will mainly describe the differences from the first embodiment, and may omit explanations of the similarities.

[0103] Figure 8 is a side view of the rotor R of the second embodiment according to this disclosure, and corresponds to Figure 1.

[0104] As shown in Figure 8, the rotor R of the second embodiment further comprises a rotor core RCP which includes a pair of second rotor core sheets 30 provided at the ends of the first rotor core sheet 20.

[0105] Furthermore, the second rotor core sheet 30 has the same structural substance as the first rotor core sheet 20. Therefore, to put it another way, the rotor R of the second embodiment can be said to be equipped with a plurality of first rotor core sheets 20, each provided at the axial (Z-direction) end of the rotor core 10.

[0106] Figure 9 is a cross-sectional view of the rotor core 10, the first rotor core sheet 20, and the second rotor core sheet 30 of the second embodiment according to this disclosure, and is a cross-sectional view at the position corresponding to line BB in Figure 6.

[0107] As explained earlier, the first rotor core sheet 20 and the second rotor core sheet 30 are of the same design, so the second rotor core sheet 30 has an opening 31 that has the same shape as the opening 21 of the first rotor core sheet 20.

[0108] On the other hand, the second rotor core sheet 30 is superimposed on the first rotor core sheet 20, slightly offset in the circumferential direction, such that the opening 31 of the second rotor core sheet 20 is slightly misaligned and overlaps with the opening 21 of the first rotor core sheet 20.

[0109] Furthermore, during the cooling process, the first magnet MG1 attempts to expand in its longitudinal direction (see Z direction). However, the stress during this expansion is borne not only by the resin in the opening 21 but also by the resin in the opening 31. As a result, the stress is distributed, and the occurrence of cracks in the resin in the opening 21 at the position overlapping with the first magnet MG1 is suppressed.

[0110] Although the above description has been based on specific embodiments, this disclosure is not limited to the embodiments described above. This disclosure also includes modifications and improvements to the embodiments, which will be clear to those skilled in the art from the claims. [Explanation of symbols]

[0111] 10...Rotor core, 11...First magnet hole, 12...Second magnet hole, 20...First rotor core sheet, 21...Opening, 22...First overlapping section, 23...Second overlapping section, MG1...First magnet, MG2...Second magnet, MS...Side section, OS1, OS2...Opening area, R...Rotor, RP...Resin section, S1, S3...Placement area, S2...First area, S4...Second area

Claims

1. It is a rotor, The rotor is A rotor core having a first magnet hole for housing a first magnet, A first rotor core sheet having an opening that contacts the axial end face of the first magnet and partially overlaps the arrangement area of ​​the first magnet hole where the first magnet is placed, The structure comprises the space between the first magnet and the first magnet hole, and a resin portion provided within the opening, A rotor in which the opening is not located in a position that overlaps with the side of the first magnet along the orientation direction of the first magnet.

2. The first magnet hole has a first area adjacent to the arrangement area where the first magnet is placed, which does not contain the first magnet. The opening includes a first overlapping portion that overlaps the first region, The rotor according to claim 1, wherein the first overlapping portion is provided in the orientation direction of the first magnet.

3. The rotor core has a second magnet hole for housing a second magnet, The rotor includes a resin portion provided between the second magnet and the second magnet hole, The second magnet hole has a second area adjacent to the area where the second magnet is placed, which does not contain the second magnet. The opening includes a second overlapping portion that overlaps the second region, The rotor according to claim 2, wherein the second overlapping portion is provided in the orientation direction of the second magnet.

4. The first overlapping portion has a larger opening area when viewed from the opening side towards the first overlapping portion than when viewed from the first region side towards the first overlapping portion. The rotor according to claim 3, wherein the second overlapping portion has a larger opening area when viewed from the opening side to the second overlapping portion than when viewed from the second region side to the second overlapping portion side.

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