JP2006280066A - Stator and rotary electric machine - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a stator in which the yield and magnetic characteristics are enhanced, and to provide a rotary electric machine equipped with that stator. <P>SOLUTION: The stator 100 comprises a teeth portion 110 composed of a dust core 130, and a yoke portion 120 provided radially outside of the teeth portion 110 wherein the yoke portion 120 has electromagnetic steel plates 140 wound continuously on the outer circumference of the dust core 130 and laminated in the axial direction (DR1 direction) of the stator 100. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a stator and a rotating electrical machine, and more particularly, to a stator manufactured using a dust core and an electromagnetic steel sheet, and a rotating electrical machine including the stator.

  Conventionally, a stator formed by combining an iron plate core and a powder core is known.

  For example, in Japanese Patent Application Laid-Open No. 2004-201483, a pair of powder cores is disposed at both axial end portions of a stator core, and a steel plate core formed by laminating steel plates is sandwiched between them. The stator comprised by this is disclosed.

  Japanese Patent Application Laid-Open No. 2003-143781 discloses a stator in which a tooth portion is formed of laminated steel plates and the outer periphery thereof is fixed with a magnetic powder compression molding.

  A stator formed by dividing a tooth portion in the circumferential direction has been conventionally known. Such a stator is described in, for example, Japanese Patent Application Publication No. 2003-244873, Japanese Patent Application Laid-Open No. 2000-278891, Japanese Patent Application Publication No. 2002-544753.

A stator in which a part of the axial end surface of the stator core is recessed or protruded in the axial direction is conventionally known. Such a stator is described in, for example, Japanese Patent Application Laid-Open Nos. 2004-40948, 2002-95191, 2003-32924, and 2001-25183.
JP 2004-201483 A JP 2003-143781 A JP 2003-244873 A JP 2000-278891 A Japanese translation of PCT publication No. 2002-544753 JP 2004-40948 A JP 2002-95191 A Japanese Patent Laid-Open No. 2003-32924 JP 2001-25183 A

  A yield may fall by forming the teeth part which has a comparatively complicated shape with a laminated steel plate.

  On the other hand, for example, Japanese Patent Application Laid-Open No. 2003-244873 discloses that the teeth portion of the stator is formed of a magnetic iron powder molded body and the magnetic steel sheet is wound around the outermost peripheral portion of the yoke portion. In order to improve the magnetic properties of the stator, the idea of continuously winding and laminating steel sheets on the outer periphery of a magnetic iron powder compact is disclosed. Not.

  The present invention has been made in view of the above problems, and an object of the present invention is to provide a stator with improved yield and magnetic characteristics, and a rotating electrical machine including the stator.

  A stator according to the present invention includes a tooth portion formed of a powder magnetic core and a yoke portion provided radially outward of the tooth portion, and the yoke portion is continuously wound around the outer periphery of the powder magnetic core. And a laminated steel plate part laminated.

  According to the above configuration, it is possible to improve the yield by configuring the teeth portion with a powder magnetic core, and improve the magnetic characteristics of the stator by continuously winding and laminating steel plates on the outer periphery of the powder magnetic core. it can.

  Here, “continuously winding and laminating a steel sheet on the outer periphery of the dust core” means that the steel sheet is laminated by winding the outer periphery of the dust core so as to make at least one round. . Further, “winding a steel plate on the outer periphery of the dust core” includes a case of “assembling the dust core on the inner periphery of the steel plate after winding the steel plate”.

  In the stator, the dust core includes a first portion constituting the teeth portion, a second portion provided on the outer periphery of the first portion, and projecting in the axial direction of the stator from the axial end surface of the first portion; The laminated steel plate part is preferably formed by being wound around a dust core so as to reach the axial end of the second part.

  Use the dead space near the coil end by winding the laminated steel sheet so that the outer periphery of the dust core protrudes axially from the axial end face and reaches the end (tip) of the protruding part. Thus, the effective cross-sectional area of the magnetic path can be ensured. Further, the shape of the dust core can be easily adjusted by changing the shape of the mold. Therefore, according to the above configuration, it is possible to easily obtain a stator having a reduced outer diameter, that is, a downsized stator.

  A rotating electrical machine according to the present invention includes the above-described stator. Thereby, the rotating electrical machine excellent in yield and magnetic characteristics is provided.

  According to the present invention, the yield and magnetic properties of the stator can be improved.

  Embodiments of a stator and a rotating electrical machine based on the present invention will be described below. Note that the same or corresponding portions are denoted by the same reference numerals, and the description thereof may not be repeated.

  FIG. 1 is an axial cross-sectional view showing a rotating electrical machine according to Embodiments 1 to 3 described later. Referring to FIG. 1, rotating electric machine 1 includes a ring-shaped stator 100 and a rotor 200 that is rotatably fixed inward in the radial direction of stator 100. In the following description, the DR1 direction in FIG. 1 may be referred to as “stator axial direction”, and the DR2 direction in FIG. 1 may be referred to as “stator circumferential direction”.

  Stator 100 and rotor 200 are formed in a housing (not shown in FIG. 1). Stator 100 has teeth portion 110 and yoke portion 120. A coil (not shown in FIG. 1) is wound around the tooth portion 110. The rotor 200 rotates in the circumferential direction of the stator (DR2 direction).

(Embodiment 1)
FIG. 2 is an axial sectional view showing the stator 100 included in the rotating electrical machine according to the first embodiment. FIG. 3 is a side sectional view of the stator 100 shown in FIG. 2 as viewed from the direction of arrow III.

  Referring to FIGS. 2 and 3, stator 100 according to the present embodiment includes a dust core 130 composed of a dust core formed by molding a powder containing magnetic powder such as iron, and a dust core 130. And a magnetic steel sheet 140 wound around the outer periphery. The dust core 130 mainly constitutes the tooth portion 110 of the stator 100, and the electromagnetic steel plate 140 constitutes a part of the yoke portion 120 of the stator 100.

  The powder core 130 is divided and formed in the circumferential direction. Thereby, for example, the concentrated winding coil can be easily assembled. The divided powder cores 130 are combined, and the magnetic steel sheet 140 is wound around the outer periphery thereof to form a stator core.

  The electromagnetic steel sheet 140 is made of a strip-shaped electromagnetic steel sheet (for example, width: about 2 to 5 mm, thickness: about 0.2 to 0.35 mm) that is a thin plate of soft magnetic material, and spirals along the outer peripheral surface of the dust core 130. It is wound into a shape. Thereby, the electromagnetic steel sheet 140 is laminated | stacked on the axial direction (arrow DR1 direction) of the stator 100. FIG. And the electromagnetic steel plate 140 fastens the powder core 130 divided | segmented into the circumferential direction (arrow DR2 direction) of the stator 100. FIG.

  Next, a manufacturing process of the stator 100 according to the present embodiment will be described.

  First, the raw material powder which comprises the compacting core 130 is prepared. As the raw material powder, for example, pure iron (Fe) and Fe—Si atomized powder mixed with about 0.3 wt% silicon resin, stirred and dried can be used.

Next, powder molding is performed at a predetermined surface pressure (for example, about 1176 MPa). As a molding method, for example, a method in which a mold lubrication molding method and a warm molding method are combined can be used. Next, the molded body is subjected to heat treatment (for example, 750 ° C. × 30 min, in an N ₂ atmosphere) (sintering step). By the above process, the dust core 130 as a divided core divided in the circumferential direction of the stator is formed.

  Further, the coil is assembled in a single state of the split core. Here, a coil (concentrated winding coil) is inserted into the tooth portion.

  And a division | segmentation core is aligned in the circumferential direction (arrow DR2 direction), a cylindrical core is formed, and the electromagnetic steel plate 140 is wound helically along the outer peripheral surface of a cylindrical core. Thereby, a split core is fastened.

  In addition, after winding the electromagnetic steel plate 140 in a spiral shape, the dust core 130 may be assembled to the inner periphery of the wound electromagnetic steel plate 140.

  As described above, the stator 100 according to the present embodiment includes the tooth portion 110 configured by the dust core 130 that is a dust core, and the yoke portion 120 provided radially outward of the teeth portion 110. The yoke portion 120 has a magnetic steel sheet 140 that is continuously wound around the outer periphery of the dust core 130 and stacked. The electromagnetic steel plate 140 constitutes a “laminated steel plate portion”.

  When the teeth portion of the stator is made of an electromagnetic steel plate, the yield may be reduced. On the other hand, a yield can be improved by comprising the teeth part 110 with a powder magnetic core. In the stator 100, the magnetic properties of the stator 100 can be improved by continuously winding the electromagnetic steel sheet 140 around the outer periphery of the dust core 130. Typically, for example, a directional electromagnetic steel sheet is used as the electromagnetic steel sheet 140 and is wound around the outer periphery of the dust core 130 with its easy magnetization direction coincident with the circumferential direction of the stator 100, so that the stator 100 in the yoke portion 120 is wound. The magnetic flux easily flows in the circumferential direction. Further, from a viewpoint different from the above, the strength of the stator 100 can be improved by disposing the relatively high strength electromagnetic steel sheet 140 on the outer periphery of the dust core 130.

  FIG. 7 is an axial cross-sectional view showing stator 100A compared with stator 100 according to the present embodiment. FIG. 8 is a side sectional view of the stator 100A shown in FIG. 7 as viewed from the direction of arrow VIII.

  7 and 8, in stator 100A having teeth portion 110A and yoke portion 120A, nonmagnetic ring 140A is attached on the outer periphery of dust core 130A divided in the circumferential direction, so that circumferential direction The compacted powder core 130A is fastened. The non-magnetic ring 140A does not contribute to the improvement of the magnetic characteristics of the stator 100A, and hinders the miniaturization of the stator 100A.

  On the other hand, in the stator 100, a magnetic steel sheet 140 wound continuously without a break is used as a fastening ring for the dust core 130, which is a split core. Thereby, since the fastening ring can be used as a magnetic path, the magnetic characteristics of the stator can be improved and the size can be reduced.

  Further, in the stator 100, the electromagnetic steel sheet 140 is spirally wound around the outer periphery of the dust core 130. As a result, the electromagnetic steel sheets 140 are laminated in the axial direction of the stator 100 outside the powder core 130 in the radial direction. Therefore, the eddy current loss when the magnetic flux flows from the dust core 130 to the electromagnetic steel plate 140 is suppressed.

  Furthermore, by winding the electromagnetic steel sheet 140 in a spiral shape, the yield is improved as compared with the case where the ring-shaped electromagnetic steel sheets are laminated.

  In the present embodiment, the case where the powder core 130 is formed as a divided core divided in the circumferential direction has been mainly described. However, as one modification, the powder core 130 is integrally formed in the circumferential direction. May be. Also in this case, the magnetic properties of the stator can be improved by winding and laminating electromagnetic steel sheets around the dust core 130.

(Embodiment 2)
FIG. 4 is an axial sectional view showing a stator 100 included in the rotating electrical machine according to the second embodiment. 5 is a side sectional view of the stator shown in FIG.

  Referring to FIGS. 4 and 5, stator 100 according to the present embodiment is a modification of the stator according to embodiment 1, and dust core 130 that is a dust core constitutes tooth portion 110. The first portion 1100 is provided on the outer periphery of the first portion 1100, and the second portion 1200 protrudes in the axial direction of the stator 100 from the axial end surface of the first portion 1100. The second portion 1200 constitutes a part of the yoke portion 120 of the stator 100. The first and second portions 1100 and 1200 are formed as an integral dust core.

  As shown in FIG. 5, the electromagnetic steel sheet 140 is typically provided so as to reach from one axial end portion of the second portion 1200 to the other axial end portion. The electromagnetic steel sheet 140 is formed by being spirally wound around the outer periphery of the dust core 130 as in the first embodiment. The electromagnetic steel sheet 140 constitutes a part of the yoke part 120 of the stator 100.

  In the rotating electrical machine according to the present embodiment, the position of the axial end surface of rotor 200 substantially matches the position of the axial end surface of first portion 1100 of dust core 130. That is, the second portion 1200 of the dust core 130 protrudes in the axial direction of the stator 100 from the axial end surface of the rotor 200.

  Next, a manufacturing process of the stator 100 according to the present embodiment will be described.

  First, the raw material powder which comprises the compacting core 130 is prepared. As the raw material powder, the same powder as in Embodiment 1 can be used.

  Next, powder molding and heat treatment are performed. In the present embodiment, the shape of the mold is different from that of the first embodiment. That is, a mold having a shape corresponding to the shape of the first and second portions 1100 and 1200 described above is prepared. Note that the methods of powder molding and heat treatment are the same as those in the first embodiment. Thereby, the dust core 130 which has a level | step difference in the radial direction of the stator 100 is formed.

  Thereafter, the coil is assembled and the split core is fastened. The coil assembly and core fastening methods are the same as those in the first embodiment.

  As described above, the effective cross-sectional area of the magnetic path can be increased by causing the yoke portion 120 formed of the second portion 1200 of the dust core 130 and the electromagnetic steel plate 140 to protrude in the axial direction of the stator 100. In other words, the outer diameter of the stator for forming a rotating electrical machine having the same output can be reduced. And the electromagnetic steel plate 140 has a function of fastening the split core.

  Here, the protruding height of the second portion 1200 is preferably about the height of the coil 150 (or less than the height of the coil 150) on the axial end surface of the tooth portion 110 (for example, about 5 mm). Thereby, the effective cross-sectional area of the magnetic path can be ensured by effectively utilizing the area that has conventionally been a dead space near the coil end.

  Note that the dust core 130 having a shape as shown in FIG. 4 can be easily manufactured by deforming the mold.

  FIG. 9 is an axial sectional view showing a stator 100B compared with the stator 100 according to the present embodiment. FIG. 10 is a side sectional view of the stator 100B shown in FIG.

  9 and 10, in stator 100B having teeth portion 110B and yoke portion 120B, steel plate core 130B in which electromagnetic steel plates are laminated is used as the stator core. In this case, in order to form a stepped structure in which the yoke portion 120B protrudes in the axial direction, it is necessary to provide a separate step. Further, even if the yoke portion 120B of the steel plate core 130B is protruded in the axial direction, the magnetic flux flowing through the core is not necessarily transmitted sufficiently to the tip of the protrusion.

  In contrast, in the stator 100, a step is provided in the dust core 130, which is a dust core. Since this step can be formed only by changing the shape of the mold, it is not necessary to provide a separate step for providing the step. Further, the magnetic flux flowing in the dust core 130 is sufficiently transmitted to the axial end portion of the second portion 1200 that is the protruding portion. Therefore, the portion formed so as to protrude in the axial direction of the stator sufficiently functions as a portion that improves the effective sectional area of the magnetic path. As a result, the outer diameter of the stator can be reduced (for example, φ190 (mm) in the structure shown in FIGS. 9 and 10 is φ183 (mm) in the structure shown in FIGS. 4 and 5. Can be.) That is, according to the configuration shown in FIGS. 4 and 5, the stator can be miniaturized.

  In the stator 100, the electromagnetic steel plate 140 is provided so as to reach from one axial end of the second portion 1200 to the other axial end. As a result, the electromagnetic steel sheet 140, which is a fastening ring, can be effectively utilized as a magnetic path, so that the magnetic characteristics of the stator can be improved and the size can be reduced.

  In the present embodiment, the case where the powder core 130 is formed as a divided core divided in the circumferential direction has been mainly described. However, as one modification, the powder core 130 is integrally formed in the circumferential direction. May be. Also in this case, by providing the above-described step in the dust core 130, the magnetic characteristics of the stator can be improved or the outer diameter of the stator can be reduced.

(Embodiment 3)
FIG. 6 is an axial cross-sectional view showing stator 100 included in the rotating electrical machine according to the third embodiment.

  Referring to FIG. 6, a stator 100 according to the present embodiment is a modification of the stator according to the first and second embodiments, and a dust core 130, which is a dust core, is connected to first core 131 and The two cores 132 are formed separately. The first core 131 has a concave portion on the joint surface with the second core 132, and the second core 132 has a convex portion that fits the concave portion on the joint surface with the first core 131. As a result, the first and second cores 131 and 132 are positioned. A magnetic steel sheet 140 is spirally wound around the outer periphery of the combined first and second cores 131 and 132.

  The first core 131 constitutes a tooth part 110 and a part of the yoke part 120 of the stator 100. On the other hand, the second core 132 and the electromagnetic steel plate 140 constitute a part of the yoke portion 120 of the stator 100.

  As shown in FIG. 6, the width of the portion included in the yoke portion 120 in the first core 131 is equal to or less than the width of the tooth portion 110. Therefore, it is possible to assemble the coil 150 in the direction of the arrow DR3 from the outer peripheral side of the first core 131.

  Next, a manufacturing process of the stator 100 according to the present embodiment will be described.

  First, the raw material powder which comprises the compacting core 130 is prepared. As the raw material powder, the same powder as in Embodiment 1 can be used.

  Next, powder molding and heat treatment are performed. In the present embodiment, the shape of the mold is different from that of the first embodiment. That is, two types of molds having shapes corresponding to the shapes of the first and second cores 131 and 132 described above are prepared. Note that the methods of powder molding and heat treatment are the same as those in the first embodiment.

  Thereafter, the coil is assembled and the split core is fastened. In the present embodiment, coil 150 is assembled in the direction of arrow DR3 from the yoke portion 120 side (outer peripheral side). The method for fastening the split core is the same as in the first embodiment.

  FIG. 11 is an axial cross-sectional view showing stator 100C compared with stator 100 according to the present embodiment.

  Referring to FIG. 11, in stator 100C having teeth portion 110C and yoke portion 120C, a stator core is formed by winding an electromagnetic steel plate around powder core 130C. Here, the width of the portion constituting the yoke portion 120C in the powder core 130C is larger than the width of the portion constituting the tooth portion 110C. Therefore, the coil 150C needs to be assembled in the direction of the arrow DR4 from the tooth part 110 side (inner peripheral side). In this case, the coil 150C is affected by the shape of the tooth tip 111C. Therefore, improvement of the coil space factor is limited. In other words, the shape of the tooth tip 111C is affected by the shape of the coil 150C. Therefore, the magnetic path control at the tooth tip 111C is limited.

  On the other hand, in the stator 100, the coil 150 can be assembled in the direction of the arrow DR3 from the outer peripheral side of the first core 131. Therefore, the shape of the coil 150 can be determined without being restricted by the shape of the tooth tip 111. In other words, the shape of the tooth tip 111 can be determined without being restricted by the shape of the coil 150. Therefore, according to the stator according to the present embodiment, it becomes easy to improve the space factor of coil 150 and to control the magnetic path at tooth tip 111.

  As mentioned above, although embodiment of this invention was described, combining the characteristic part of Embodiment 1-3 mentioned above suitably is planned from the beginning.

  In the first to third embodiments described above, the example in which the electromagnetic steel sheet 140 is spirally wound and laminated in the axial direction of the stator 100 has been mainly described. It is also conceivable to laminate the electromagnetic steel sheets 140 in the radial direction on the outer periphery.

  Thus, it should be thought that embodiment disclosed this time is an illustration and restrictive at no points. The scope of the present invention is defined by the terms of the claims, and is intended to include any modifications within the scope and meaning equivalent to the terms of the claims.

It is an axial sectional view showing a rotating electrical machine according to Embodiments 1 to 3 of the present invention. It is an axial sectional view showing a stator included in the rotary electric machine according to Embodiment 1 of the present invention. FIG. 3 is a side sectional view of the stator shown in FIG. 2 as viewed from the direction of arrow III. It is an axial sectional view showing a stator included in a rotary electric machine according to Embodiment 2 of the present invention. FIG. 5 is a side sectional view of the stator shown in FIG. 4 viewed from the direction of arrow V. It is an axial sectional view showing a stator included in a rotary electric machine according to Embodiment 3 of the present invention. FIG. 3 is an axial sectional view showing a stator to be compared with the stator shown in FIG. 2. It is the sectional side view which looked at the stator shown by FIG. 7 from the direction of arrow VIII. FIG. 5 is an axial sectional view showing a stator compared with the stator shown in FIG. 4. FIG. 10 is a side sectional view of the stator shown in FIG. 9 viewed from the direction of arrow X. FIG. 7 is an axial sectional view showing a stator to be compared with the stator shown in FIG. 6.

Explanation of symbols

  1 Rotating electrical machine, 100, 100A, 100B, 100C Stator, 110, 110A, 110B, 110C Teeth part, 111, 111C Teeth tip part, 120, 120A, 120B, 120C Yoke part, 130, 130A, 130C Powder core, 130B Steel plate core, 131 1st core, 132 2nd core, 140 electromagnetic steel plate, 140A non-magnetic ring, 150, 150B, 150C coil, 200 rotor, 1100 first part, 1200 second part.

Claims (3)

A teeth portion composed of a dust core;
A yoke portion provided radially outward of the teeth portion,
The yoke portion has a laminated steel plate portion that is continuously wound around and laminated on the outer periphery of the dust core. The dust core includes a first portion constituting a tooth portion and a second portion provided on an outer periphery of the first portion and projecting in an axial direction of the stator from an axial end surface of the first portion. Have
2. The stator according to claim 1, wherein the laminated steel plate portion is formed by being wound around the dust core so as to reach an axial end portion of the second portion.   A rotating electrical machine comprising the stator according to claim 1.

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