JP2014222958A - Laminate iron core for rotary electric machine - Google Patents

Abstract

[PROBLEMS] To effectively eliminate conduction between thin plate magnetic members through burrs and reduce eddy current loss without reducing a magnetic path cross-sectional area or deteriorating magnetic characteristics in a laminated iron core of a rotating electrical machine. . A stator core of a rotating electrical machine is formed by laminating a plurality of core members 12 formed by punching a thin plate-like magnetic member whose both surfaces are covered with an insulating layer, and protrudes in a radial direction. A plurality of teeth portions 16 are provided at a predetermined pitch in the circumferential direction. The teeth forming portion 22 of the iron core member 12 that forms the teeth portion 16 does not have a straight line passing through the rotation center D of the rotating electrical machine as the axis of symmetry, and the teeth portions 16 of the stator core are adjacent to the iron core member 12 at one or more points in the stacking direction. Since the side edge portions 22a and 22b facing the circumferential direction of the teeth forming portion 22 are stacked so as to be in different positions, the positions of the side edge portions 22a and 22b are shifted. [Selection] Figure 4

Description

  The present invention relates to a laminated iron core of a rotating electrical machine that is mainly used as a generator and a motor mounted on a hybrid vehicle, an electric vehicle, or the like.

  Conventionally, in a rotating electric machine, in order to reduce iron loss, a plurality of thin plate-like magnetic members, each having an insulating layer formed by coating or the like on both sides, formed into a predetermined shape by press punching are laminated to form a cylindrical shape. It is known to constitute a stator core. The stator core generally includes a substantially annular yoke portion and a plurality of tooth portions formed to protrude to the inner peripheral side of the yoke portion. A stator coil of a rotating electrical machine is configured by winding a stator coil around the teeth portion by a winding method such as concentrated winding or distributed winding. When the rotating electrical machine is a motor, a rotating magnetic field is formed inside the stator by applying, for example, a three-phase AC voltage as a driving voltage to the stator coil, thereby rotating the rotor disposed inside the stator. It is like that.

  In the thin plate-like magnetic member subjected to press punching as described above, burrs are often formed at the punched edge. Therefore, on the side surface along the axial direction of the stator core formed by laminating magnetic members, a portion conducting through burrs between a plurality of magnetic members adjacent in the axial direction is generated, and eddy current loss increases. It may be a factor that reduces motor efficiency.

  In relation to this, Japanese Patent Application Laid-Open No. 2003-61273 (Patent Document 1) discloses that only the tip of the protrusion of the thin plate-like magnetic member that constitutes the tooth portion serving as the magnetic pole of the stator core is formed thinner by pressing. In addition, it is described that when a gap is formed, a gap is formed between the tip portions of the protrusions, thereby eliminating the occurrence of a conductive portion between adjacent magnetic members.

JP 2003-61273 A

  As described in the above-mentioned Patent Document 1, the following problems (1) to (3) are caused by crushing and thinning the protrusions constituting the teeth part. (1) The magnetic path cross-sectional area at the tip of the tooth portion is reduced, and the motor torque is reduced. (2) Stress concentration occurs at the boundary of the crushed portion, and the magnetic characteristics deteriorate. (3) Since the conduction portion on the side surface of the tooth portion where the contribution of eddy current loss is large is not eliminated, the loss cannot be sufficiently reduced.

  It is an object of the present invention to effectively eliminate conduction between thin magnetic members through burrs and reduce eddy current loss without reducing magnetic path cross-sectional area or deteriorating magnetic properties. It is to provide a laminated core of an electric machine.

  The laminated iron core of the rotating electrical machine according to the present invention is configured by laminating a plurality of core members formed by punching a thin plate-like magnetic member whose both surfaces are covered with an insulating layer, and projects in the radial direction. A laminated iron core of a rotating electrical machine having a plurality of salient pole portions at a predetermined pitch in the circumferential direction, wherein at least one of salient pole forming portions of the iron core member forming the salient pole portion has a rotational center of the rotating electrical machine. A straight line passing through is not used as an axis of symmetry, and the salient pole portions of the laminated core are arranged at different positions in the circumferential direction of the salient pole forming portion of the adjacent iron core member at one or more points in the stacking direction. As a result of the lamination, the position of the side edge is shifted.

  In the laminated iron core of the rotating electrical machine according to the present invention, it is preferable that all laminated iron core materials are formed in the same shape.

  In the laminated core of the rotating electrical machine according to the present invention, the salient pole forming portion of the core material may be formed in an asymmetric shape with respect to a straight line extending in the radial direction through the rotation center of the rotating electrical machine.

  Moreover, in the laminated iron core of the rotating electrical machine according to the present invention, it is preferable that the shift amount of the side edge portion of the salient pole forming portion adjacent in the laminating direction is set to be equal to or greater than the plate thickness of the thin magnetic member.

  Moreover, in the laminated core of the rotating electrical machine according to the present invention, the core member has a surface on the side where burrs are formed by punching and a back surface on the opposite side, and the two core members adjacent in the axial direction. The positions of the side edge portions of the salient pole forming portions may be shifted by stacking the surfaces facing each other or the back surfaces.

  Furthermore, in the laminated iron core of the rotating electrical machine according to the present invention, the iron core member has a rotationally symmetric shape, and the other iron core member with respect to one iron core member is 360 ° with respect to the rotation center of the rotating electric machine. May be shifted by an integral multiple of an angle divided by the number of salient pole portions, and the position of the side edge portion of the salient pole forming portion may be shifted.

  According to the laminated iron core of the present invention, the salient pole forming portion of the iron core member that forms the salient pole portion is shifted by the positions of the side edge portions facing in the circumferential direction being adjacent to each other in the laminating direction. It is possible to suppress conduction between iron core members via burrs formed by punching on the circumferential side surface of the pole portion, and as a result, eddy current loss can be reduced.

It is a partial expansion perspective view of the stator core of the rotary electric machine which is 1st Embodiment of this invention. It is a fragmentary top view of the iron core member which comprises the stator core of FIG. It is a partial top view in the state where the iron core member which constitutes the stator core of Drawing 1 was turned upside down. It is a fragmentary top view which shows the state which accumulated and laminated | stacked the iron core member of FIG. 2 and FIG. It is EE sectional drawing in FIG. It is a partial top view in the front direction of the iron core member which comprises the stator core of the rotary electric machine which is 2nd Embodiment of this invention. It is a fragmentary top view in the state where the iron core member shown in Drawing 6 was rotated only a predetermined angle. FIG. 8 is a partial plan view showing a state in which the iron core members of FIGS. 6 and 7 are overlapped and stacked. It is a figure corresponding to FIG. 5 which shows the modification of the lamination | stacking state of a teeth part. It is a whole perspective view which shows the rotor core of the rotary electric machine which is another aspect of this invention. It is a partially expanded perspective view of the rotor core shown in FIG.

  Hereinafter, embodiments according to the present invention will be described in detail with reference to the accompanying drawings. In this description, specific shapes, materials, numerical values, directions, and the like are examples for facilitating the understanding of the present invention, and can be appropriately changed according to the application, purpose, specification, and the like. In addition, when a plurality of embodiments and modifications are included in the following, it is assumed from the beginning that these characteristic portions are used in appropriate combinations.

<First Embodiment>
FIG. 1 is a partially enlarged perspective view of a stator core (laminated iron core) 10 of the rotating electrical machine according to the first embodiment. The stator core 10 is configured by laminating a plurality of substantially annular iron core members 12 in the axial direction, which are formed by press punching a magnetic steel plate, which is a thin plate-like magnetic member, into a predetermined shape.

  In FIG. 1, the axial direction or the stacking direction of the stator core 10 is indicated by an arrow A. The radial direction orthogonal to the axial direction is indicated by an arrow B. Furthermore, a direction along the circumference with the radial center D (see FIG. 2 etc.) of the stator core 10 as a reference is referred to as a circumferential direction, and this circumferential direction is indicated by an arrow C in FIG.

  The stator core 10 is a substantially cylindrical magnetic body, and includes a yoke portion 14 that is a cylindrical portion that is annularly connected in the circumferential direction, and a teeth portion 16 that protrudes radially inward from the inner peripheral surface of the yoke portion 14. . Although not shown in FIG. 1, the stator core 10 is provided with a plurality of teeth portions 16 at equal pitches in the circumferential direction.

  A protruding portion 18 is formed at the distal end portion on the inner peripheral side of the tooth portion 16 so as to protrude on both sides in the circumferential direction. The overhang portion 18 has a function of preventing the coil winding wound around the tooth portion 16 from coming out radially inward.

  In the present embodiment, an example in which the stator core 10 is configured as an integral member will be described. However, the present invention is not limited to this, and a split core in which the yoke portion and the teeth portion are substantially T-shaped in a plan view. The stator cores may be configured by integrally fastening a large number of divided cores by arranging the ring-shaped members in a ring shape and externally fitting a cylindrical fixing sleeve.

  FIG. 2 is a partial plan view of the iron core member 12 constituting the stator core 10 of FIG. As shown in FIG. 2, the iron core member 12 includes a yoke forming portion 20 that is laminated in the axial direction to form the yoke portion 14, and a teeth forming portion (saliency pole forming portion that is laminated in the axial direction to form the tooth portion 16. ) 22.

  In this embodiment, all the iron core members 12 constituting the stator core 10 are formed in the same shape. Therefore, punching can be performed with one type of press die. By doing in this way, compared with the case where a stator core is constituted by combining a plurality of types of iron core members, manufacture and management of the iron core member 12 as a constituent element becomes easier, and as a result, the manufacturing cost of the stator core can be reduced. There is.

  The iron core member 12 has a front surface 12a that is an upper surface when punched and a rear surface 12b (see FIG. 3) that is the opposite surface. Burrs (not shown) that protrude to the surface 12a side are formed at the edges of the yoke forming portion 20 and the teeth forming portion 22.

  The total number N of teeth forming portions 22 in the iron core member 12 (N is an integer of 2 or more) matches the total number of teeth portions 16 in the stator core 10. The teeth forming portions 22 are provided at an equal pitch in the circumferential direction of the iron core member 12. More specifically, it is formed with a central angle pitch of an angle θ obtained by dividing 360 ° by the number N of teeth forming portions 22 with respect to the radial center D of the stator core 10 (that is, the iron core member 12). Here, the radial center D of the stator core 10 coincides with the rotation center of the rotating electrical machine including the stator core 10. In FIG. 2 (the same applies to FIGS. 3 and 4), the center pitch line 24 is indicated by a one-dot chain line.

  The teeth forming portion 22 is formed by extending in the radial direction with a constant width H except for the radially inner protrusions 18a and 18b. In the present embodiment, the teeth forming portion 22 is formed in a substantially rectangular shape having a short side direction width H, for example.

  The teeth forming portion 22 has an asymmetric shape with respect to a straight line passing through the radial center D of the stator core 10. In other words, the teeth forming portion 22 does not use a straight line extending in the radial direction through the rotation center of the rotating electrical machine as a symmetric axis. Specifically, the teeth forming portion 22 is parallel so that the equal dividing line 26 that bisects the short side width H is shifted by a distance s from the central pitch line 24 corresponding to the teeth forming portion 22. Is formed. Thus, with reference to the center pitch line 24, the width w1 to the one side edge 22a facing the circumferential direction of the teeth forming portion 22 and the width to the other side edge 22b facing the circumferential direction of the teeth forming portion 22 w2 is not equal. In this embodiment, the relationship is w1 <w2. In the present embodiment, the side edge portions 22 a and 22 b on both sides in the circumferential direction of the tooth forming portion 22 are formed in parallel to the center pitch line 24.

  Here, the interval s is preferably 1/2 or more of the plate thickness of the iron core member 12. This is because when the core member 12 is laminated to form the stator core 10 as will be described later, the shift amount of the side edge portions 22a and 22b of the teeth forming portion 22 is equal to or greater than the plate thickness of the core member 12. is there.

  Protrusions 18 a and 18 b that serve as the overhang portions 18 of the teeth portion 16 are formed at the distal end portion on the radially inner side of the teeth forming portion 22 by laminating the iron core member 12. The protruding portion 18a protruding from the one side edge 22a of the tooth forming portion 22 has a larger protruding dimension than the protruding portion 18b protruding from the other side edge 22b of the teeth forming portion 22.

  FIG. 3 is a partial plan view of the iron core member 12 constituting the stator core of FIG. 1 in an inverted state. In FIG. 3, the back surface 12b of the iron core member 12 is the front side of the paper.

  The iron core member 12 shown in FIG. 3 has the same configuration as that shown in FIG. However, here, the one side edge 22a of the teeth forming portion 22 whose width between the central pitch line 24 and the central pitch line 24 is shown on the right side of the central pitch line 24, and the width between the central pitch line 24 is w2. It should be noted that the other side edge 22 b of a certain tooth forming portion 22 is shown on the left side of the center pitch line 24.

  FIG. 4 is a partial plan view when the iron core member 12 of FIG. 2 and the iron core member 12 of FIG. 5 is a cross-sectional view taken along line EE in FIG. As described above, the core member 12 has the front surface 12a on the side where burrs are formed by punching and the back surface 12b on the opposite side, and in FIG. 5, any two core members 12 adjacent in the axial direction are provided. Are laminated with the front surfaces or the back surfaces 12b facing each other.

  When the iron core member 12 shown in FIG. 2 and the iron core member 12 shown in FIG. 3 are alternately laminated so that the center pitch lines 24 coincide with each other, as shown in FIG. 4 and FIG. The side edge portions 22a and 22b of the tooth forming portion 22 of the iron core member 12 and the side edge portions 22a and 22b of the tooth forming portion of the iron core member 12 which are turned upside down are stacked so as to be at different positions. Part 16 is configured.

  Here, as shown in FIG. 5, the side edges 22 a and 22 b of the teeth forming portion 22 of the iron core member 12 in the face-up state, and the side edges 22 a and 22 b of the teeth forming portion 22 of the iron core member 12 in the face-down state, Are offset from each other by a distance of 2 s. As described above, the shift width 2s is set to be equal to or greater than the plate thickness of the iron core member 12. Therefore, even if burrs generated by punching are formed at the edge of the iron core member 12, it is effective for the adjacent iron core members 12 to conduct through the burr on the side surface in the circumferential direction of the teeth portion 16 of the stator core 10. As a result, eddy current loss can be reduced.

  In the present embodiment, the protrusions 18a and 18b formed at the tip of the tooth forming portion 22 of the iron core member 12 have different projecting dimensions so that when the stator core 10 is configured, The overhang portion 18 is configured to be aligned in the axial direction. Thereby, even if it is the arrangement which side edge parts 22a and 22b shifted between iron core members 12 which adjoin in the peripheral direction side of teeth part 16, magnetic path sectional area of overhanging part 18 of teeth part 16 is reduced. Without this, it is possible to secure a magnetic path cross-sectional area through which the magnetic flux from the rotor (not shown) passes.

  In the present embodiment, the case in which the teeth forming portion 22 has a symmetrical shape with the equidistant line 26 as the axis of symmetry has been described. However, the present invention is not limited to this, and the teeth forming portion has such an axis of symmetry. The shape may not be used.

Second Embodiment
Next, with reference to FIG. 6 thru | or FIG. 8, the stator core 10A of the rotary electric machine which is 2nd Embodiment is demonstrated. In the present embodiment, the same components as those in the first embodiment described above are denoted by the same or similar reference numerals, and redundant description will be appropriately omitted.

  FIG. 6 is a partial plan view of the iron core member 12 </ b> A constituting the stator core 10 </ b> A of the rotating electrical machine according to the second embodiment facing the front. FIG. 7 is a partial plan view in a state where the core member 12A shown in FIG. 6 is rotated by a predetermined angle. FIG. 8 is a partial plan view showing a state in which the iron core members 12A of FIGS.

  Also in this embodiment, all the iron core members 12A constituting the stator core 10A are formed in the same shape. However, the present embodiment is different from the first embodiment in that the stator core 10A is configured by stacking the core member 12A by changing the circumferential position of the core member 12A, instead of alternately turning the core members 12A upside down and stacking them.

  The stator core 10 </ b> A of the present embodiment includes the teeth portions 16 whose total number is an even number. Further, as shown in FIG. 6, the iron core member 12A constituting the stator core 10A has a teeth forming portion 22A formed in an asymmetric shape with respect to a straight line extending in the radial direction through the radial center D of the stator core 10A, Teeth forming portions 22B formed symmetrically with respect to a straight line extending in the radial direction through the radial center D of the stator core 10A are alternately formed at equal pitches (center angle pitch θ) in the circumferential direction. . That is, the iron core member 12A has a rotationally symmetric shape, and has an n (= 180 / θ) -fold symmetric shape.

  More specifically, in the asymmetrical tooth forming portion 22A, the equipartition line 26 that divides the short-side direction width H into two is parallel to the center pitch line 24 corresponding to the tooth forming portion 22A by a distance t. It is formed to become. In other words, the teeth forming portion 22A does not use a straight line extending in the radial direction through the rotation center of the rotating electrical machine as a symmetry axis. Thus, with reference to the center pitch line 24, the width w1 to the one side edge 22a facing the circumferential direction of the teeth forming portion 22 and the width to the other side edge 22b facing the circumferential direction of the teeth forming portion 22 w2 is not equal. In this embodiment, the relationship is w1 <w2. In the present embodiment, the side edge portions 22 a and 22 b on both sides in the circumferential direction of the tooth forming portion 22 </ b> A are formed in parallel to the center pitch line 24. Here, the interval t is preferably equal to or greater than the thickness of the iron core member 12A. As will be described later, the amount of deviation between the side edge portions 22a and 22b of the tooth forming portion 22A and the side edge portions 22c and 22d of the tooth forming portion 22B when the stator core 10A is configured by stacking the iron core members 12A is the iron core. This is because the thickness is equal to or greater than the thickness of the member 12A.

  On the other hand, in the symmetrical tooth forming portion 22B, the equal dividing line that bisects the short side width H is coincident with the central pitch line 24, and the central pitch line 24 is the axis of symmetry. That is, the width from the center pitch line 24 to the side edge portions 22c and 22b on both sides in the circumferential direction is H / 2.

  The iron core member 12A shown in FIG. 7 is shown in a state where the iron core member 12A shown in FIG. 6 is rotated around the radial center D by an angle θ, and an asymmetrical tooth forming portion 22A and a symmetrical tooth forming portion 22B. Is a position shifted by one from the state shown in FIG.

  Stator core 10A as shown in FIG. 8 is formed by alternately stacking and stacking iron core member 12A shown in FIG. 6 and iron core member 12A shown in FIG. 7 so that center pitch lines 24 coincide. The cross section of the teeth portion 16 of the stator core 10A is substantially the same as that shown in FIG.

  In the teeth portion 16 of the stator core 10A of the present embodiment, the asymmetrical tooth forming portions 22A and the symmetrical tooth forming portions 22B are alternately stacked so that the side edge portions are at different positions. Therefore, the side edge portions 22a and 22b of the tooth forming portion 22A and the side edge portions 22c and 22d of the tooth forming portion 22B are shifted from each other by a distance t. As described above, the deviation width t is set to be equal to or greater than the thickness of the iron core member 12. Therefore, even if burrs generated by punching are formed at the edge of the iron core member 12, it is effective that the iron core members 12 </ b> A adjacent to each other on the circumferential side surface of the teeth portion 16 of the stator core 10 </ b> A conduct through the burr. As a result, eddy current loss can be reduced.

  In the present embodiment, the total number of the tooth portions 16 is an even number, and an example in which one type of asymmetrically shaped tooth forming portion 22A and one type of symmetrically shaped tooth forming portion 22B are alternately provided has been described. However, the present invention is not limited to this. For example, the number of asymmetrical teeth forming portions may be increased so as to be larger than that of the symmetrically shaped teeth forming portions. In that case, the symmetrically shaped teeth forming portions are not necessarily provided. Moreover, it is good also as a plurality of types of asymmetrical tooth formation parts, and the total number of teeth parts may become an odd number by combining a symmetrical tooth formation part with them.

  In the above description, the iron core member 12A shown in FIG. 6 and the iron core member 12A shown in FIG. 7 rotated by an angle θ in the circumferential direction are overlapped with each other. However, the iron core member 12A shown in FIG. The rotation angle may be an integral multiple of an angle θ obtained by dividing 360 ° by the total number N of the tooth portions 16.

  In the above description, the positions of the side edge portions of the tooth forming portions constituting the tooth portion 16 are alternately shifted in the stacking direction, but the present invention is not limited to this, and the side edge portions of adjacent iron core members are not limited thereto. As long as the positions of are different. For example, as shown in FIG. 9, the above-described symmetrical teeth forming portion 22B and two types of asymmetrically shaped teeth forming portions 22A, 22C are laminated in combination, and the teeth forming portions 22A, 22B, 22C side. You may make it shift the position of an edge.

  Further, in the first and second embodiments, the example in which the teeth forming portions 22, 22A, 22B constituting the teeth portions 16 of the stator cores 12, 12A are alternately shifted in the axial direction or the stacking direction has been described. However, the present invention is not limited to this, and the position of the side edge portions of the teeth forming portions 22, 22A, 22B may be shifted at least at one or more locations in the stacking direction in at least one tooth portion. Also by this, the effect which suppresses conduction | electrical_connection between adjacent iron core members and reduces eddy current loss can be anticipated.

  Further, in the first and second embodiments, the stator core formed by laminating thin plate-like magnetic members has been described. However, the invention according to the present invention is applied to a rotor core having salient pole portions such as a DC motor and a reluctance motor. Is also applicable. FIG. 10 is an overall perspective view of the rotor core 11 to which the present invention is applied, and FIG. 11 is a partially enlarged view of FIG. The rotor core 11 includes a cylindrical portion 30 located at the center, and a plurality of salient pole portions 32 protruding outward in the radial direction on the outer peripheral surface of the cylindrical portion 30. The side surfaces 32a and 32b facing the circumferential direction of the salient pole portion 32 are the ones in which the side edge portions of the salient pole forming portions of the iron core members constituting the rotor core 11 are adjacent in the axial direction, like the stator core 10 and the like described above. It is formed so as to be shifted.

  10, 10A Stator core (laminated core), 11 Rotor core (laminated core), 12, 12A Iron core member, 12a Front surface, 12b Back surface, 14 York portion, 16 Teeth portion, 18 Overhang portion, 18a, 18b Protrusion portion, 20 Yoke formation Part, 22, 22A, 22B, 22C Teeth forming part, 22a, 22b, 22c, 22d side edge part, 24 center pitch line, 26 equipartition line, 30 cylindrical part, 32 salient pole part, 32a, 32b side face, D Radial center or rotation center, H width or short side width, N number of teeth, s, t interval, distance or width, w1, w2 width, θ angle or center angle pitch.

Claims (1)

Constructed by laminating a plurality of core members formed by punching a thin plate-shaped magnetic member whose both surfaces are covered with an insulating layer in the axial direction, and a plurality of salient pole portions protruding in the radial direction at a predetermined pitch in the circumferential direction. A rotating iron core of a rotating electric machine having
At least one of the salient pole forming portions of the iron core member that forms the salient pole portion does not have a straight line passing through the rotation center of the rotating electrical machine as an axis of symmetry, and the salient pole portion of the laminated iron core is one in the stacking direction. Lamination of rotating electrical machines in which the position of the side edge portion is shifted by being laminated so that the side edge portions in the circumferential direction of the salient pole forming portions of the adjacent iron core members that are adjacent to each other are located at different positions. Iron core.

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