JP2010115095A - Stator core and rotary electric machine - Google Patents

Abstract

Provided are a stator core and a rotating electrical machine in which iron loss and saturation of magnetic flux are suppressed by suppressing deviation of magnetic flux density.
A stator core 200 has a plurality of slits 131 formed at intervals in the circumferential direction, and an inner peripheral side connection formed at a portion located on the radially inner side of the stator core 200 with respect to the slit 131. Portion 214 and an outer peripheral side connection portion 213 formed in a portion located on the outer side in the radial direction with respect to the slit 131, and a cross section of the inner peripheral side connection portion 214 along the radial direction of the stator core 200. The cross-sectional area S3 is smaller than the cross-sectional area of the cross section of the outer peripheral side connecting portion 213 along the radial direction.
[Selection] Figure 13

Description

  The present invention relates to a stator core and a rotating electrical machine.

Conventionally, various types of rotating electric machines with various ideas have been proposed.
For example, Japanese Patent Laid-Open No. 7-255158 proposes a rotating electrical machine in which cogging torque is reduced. The rotating electrical machine described in JP-A-7-255158 includes a rotor extending in the axial direction and a stator core. The stator core is divided for each salient pole part. A pole piece is formed on each salient pole part. A first extension portion extending in the circumferential direction by the half wavelength of the cogging wave is formed on one end side of the piece pole. And the 2nd extension part extended in the opposite direction to a 1st extension part is formed in the other edge part side of a piece pole.

  Japanese Patent Application Laid-Open No. 2007-129835 proposes a rotating electrical machine and a stator core that are capable of suppressing motor noise and vibration.

  The stator core is composed of a plurality of divided cores. Each divided core is formed such that a portion located in the vicinity of the rotor in the divided surface that comes into contact with another adjacent divided core is preferentially in contact.

  Japanese Patent Laid-Open No. 2007-37317 proposes an armature core and a motor in which a reduction in cogging torque is achieved while suppressing a decrease in the output torque of the motor.

  The armature core is divided into a plurality of core pieces. Each core piece includes a tooth and a substantially arc portion protruding left and right symmetrically about the tooth. A gap is formed in all of the joint portions between the core pieces. Each gap is open to the inside of the cylindrical yoke and has a V shape extending to a middle portion in the radial direction of the cylindrical yoke.

  Japanese Patent Application Laid-Open No. 2000-245081 proposes a stator for a DC motor in which the copper loss of a winding supported by a slot is reduced without particularly increasing the number of processing steps and assembly steps of a steel plate for a stator. .

  This stator for a DC motor is formed into a cylindrical shape by laminating and laminating strip steel plates in a plurality of stages. A plurality of slots for supporting the windings are defined inside the stator. Each slot is formed such that the entrance is narrow and widens behind. A wedge-shaped cut extending in the radial direction of the stator is formed at the back of each slot.

Japanese Patent Laid-Open No. 2006-121818 describes a motor including a stator formed by combining a plurality of cores. Each core has a connecting portion and a salient pole portion having a predetermined width in the radial direction, and each core is formed to have a substantially T-shaped cross section. When a stator having a ring shape formed by combining a plurality of cores is housed in the motor housing, each core is in contact with the inner diameter portion of the connecting portion and is not in contact with the outer diameter portion.
JP-A-7-255158 JP 2007-129835 A JP 2007-37317 A JP 2000-245081 A JP 2006-121818 A

  A concave groove is formed in the radial center of the split surface of the stator core of the rotating electrical machine described in JP-A-7-255158. A connecting rod straddling the concave grooves adjacent in the circumferential direction is inserted.

  Here, in the split surface of the stator core, the first protrusion is formed in a portion adjacent to the concave portion on the radially inner side, and the portion adjacent to the concave portion on the radially outer side is formed. The second protrusion is formed. And between the laminated plates adjacent in the circumferential direction, the first contact portions and the second contact portions are in contact with each other. The contact area of the first protrusion and the contact area of the second protrusion are equal to each other.

  For this reason, the magnetic resistance when the magnetic flux passes through the first protrusion and the magnetic resistance when the magnetic flux passes through the second protrusion are substantially equal. On the other hand, the path length of the magnetic flux path passing through the first protrusion is shorter than the path length of the magnetic flux path passing through the second protrusion. For this reason, the magnetic flux from the magnet mainly passes through the first protrusion, and the magnetic flux density in the first protrusion increases.

  Thus, when the part with a high magnetic flux density arises, while a core loss becomes large, the problem that a magnetic flux becomes easy to saturate arises.

  In the stator core described in Japanese Patent Application Laid-Open No. 2007-129835, the magnetic flux flowing in the stator core passes through the inner peripheral side where the divided surface is in contact and hardly passes through the outer peripheral side where the divided surface is separated.

  For this reason, in the part located in the inner peripheral side of the stator core, the magnetic flux is likely to be saturated, and further, the magnetic flux density is increased, resulting in a problem that the iron loss is increased.

  Also in the armature core described in Japanese Patent Application Laid-Open No. 2007-37317, the gap formed between the core pieces opens toward the inside in the radial direction. And if the width | variety of this space | gap part is large, magnetic flux will not pass this space | gap part. Accordingly, the magnetic flux flowing in the armature core mainly passes through a portion of the armature core that is located on the radially outer side with respect to the gap.

  For this reason, in the armature core, the magnetic flux density in the radially outward portion is increased, and the iron loss is increased. In addition, the magnetic flux may be saturated in a portion of the armature core that is located on the radially outer side.

  A wedge-shaped cut is formed in the stator for a DC motor described in Japanese Patent Application Laid-Open No. 2000-245081. And when the width | variety of a notch | incision is large, magnetic flux will mainly flow through the outer peripheral side rather than a notch | incision among the stators for DC motors.

  For this reason, also in this stator for DC motors, there is a possibility that an increase in iron loss and saturation of magnetic flux may occur.

  In the motor described in Japanese Patent Laid-Open No. 2006-121818, the inner peripheral surface of each core is in contact and is not in contact with the outer peripheral side, so that the magnetic flux from the permanent magnet is the inner peripheral side of the stator core. The magnetic flux may be saturated.

  The present invention has been made in view of the above-described problems, and an object of the present invention is to provide a stator core and a rotating electrical machine in which iron loss and saturation of magnetic flux are suppressed by suppressing bias in magnetic flux density. Is to provide.

  The stator core according to the present invention is a stator core formed in an annular shape, and the stator core is formed with a plurality of slit portions at intervals in the circumferential direction of the stator core. A first connection portion is formed at a portion located on the inner side in the radial direction, and a second connection portion is formed at a portion located on the outer side in the radial direction with respect to the slit portion. And the cross-sectional area of the cross section of the 1st connection part along the radial direction of a stator core is smaller than the cross-sectional area of the cross section of the 2nd connection part along a radial direction.

  Preferably, the circumferential width of the slit portion decreases from the radially outer side of the stator core toward the radially inner side.

  Preferably, the stator core includes a plurality of split stator cores arranged in an annular shape, and the split stator core includes a split yoke portion extending in the circumferential direction. And the recessed part is formed in the side surface arranged in the circumferential direction among the surrounding surfaces of the said division | segmentation yoke part. And the said slit part is formed when the recessed part formed in the division | segmentation stator core adjacent to the circumferential direction arranges in the circumferential direction. The first connecting portion is formed by abutting inner circumferential side protruding portions formed on the divided stator cores adjacent in the circumferential direction. The second connection part is formed by the outer peripheral side protruding parts formed on the divided stator cores adjacent in the circumferential direction contacting each other. Preferably, a rotating electric machine including the stator core.

  A rotating electric machine according to the present invention includes an annular stator including a stator core and a coil attached to the stator core, a rotor core inserted into the stator and rotatably supported, and a rotor including a magnet provided on the rotor core. .

  The stator core includes a yoke portion extending in the circumferential direction of the stator, and a stator tooth extending from the yoke portion toward the radially inner side of the stator. The yoke portion is formed with a plurality of slit portions formed at intervals in the circumferential direction and extending in the radial direction. The magnetic flux radiated from the magnet reaches the stator from the rotor, passes through the stator, and passes through a magnetic circuit reaching the rotor from the stator. Furthermore, the total width in the circumferential direction of the slit portions located in the magnetic circuit is smaller than the gap between the rotor and the stator teeth.

  Preferably, a plurality of stator teeth are formed at intervals in the circumferential direction, and a slot portion capable of accommodating a coil is formed between the stator teeth. The slit portion reaches the slot portion.

  Preferably, a plurality of the stator teeth are formed at intervals in the circumferential direction, a slot portion capable of accommodating a coil is formed between the stator teeth, and the slit portion is radially outward with respect to the slot portion. Located on the side.

  Preferably, among the slit portions, the distance between the radially outer end portion of the slit portions and the outer peripheral surface of the stator core is a portion located at the radially inner end portion, and the slot portion. Longer than the distance to the portion located at the outer end in the radial direction. Preferably, the circumferential width of the slit portion decreases from the radially inner side of the stator core toward the radially outer side.

  According to the stator core and the rotating electric machine according to the present invention, it is possible to suppress the deviation of the magnetic flux density and to suppress the iron loss and the saturation of the magnetic flux.

  A stator core according to the present embodiment and a rotating electrical machine including the stator core will be described with reference to FIGS. 1 to 13.

  Note that in the embodiments described below, when referring to the number, amount, and the like, the scope of the present invention is not necessarily limited to the number, amount, and the like unless otherwise specified. In the following embodiments, each component is not necessarily essential for the present invention unless otherwise specified. In addition, when there are a plurality of embodiments below, it is planned from the beginning to appropriately combine the features of each embodiment unless otherwise specified.

(Embodiment 1)
FIG. 1 is a side sectional view of a rotating electrical machine according to Embodiment 1 of the present invention. As shown in FIG. 1, the rotating electrical machine 100 includes a rotor 120 fixed to a rotating shaft 110 that is rotatably provided around a rotation center axis O, and an annular stator provided around the rotor 120. 130.

  The rotor 120 is provided to be rotatable about the rotation center axis O. The rotor 120 includes a rotor core 121 formed in an annular shape and a plurality of permanent magnets 122 provided on the rotor core 121. A permanent magnet insertion hole 126 extending in the direction of the rotation center axis O is formed on the outer peripheral edge side of the rotor core 121. The permanent magnet 122 is inserted into the permanent magnet insertion hole 126.

  The permanent magnet 122 is fixed in the permanent magnet insertion hole 126 by a resin 124 filled in the permanent magnet insertion hole 126. A magnet pair is formed by the two permanent magnets 122 that are close to each other in the circumferential direction. The directions of the magnetic poles of the permanent magnet 122 constituting the magnet pair are the same. The directions of the magnetic poles of the magnet pairs adjacent in the circumferential direction are opposite to each other.

  The stator 130 includes a stator core 200 formed in an annular shape and a coil 132 attached to the stator core 200. Coil 132 is, for example, a three-phase coil including a U-phase coil, a V-phase coil, and a W-phase coil. Each coil is supplied with an alternating current having a different phase.

  2 is a cross-sectional view taken along line II-II in FIG. In FIG. 2, the coil 132 is omitted.

  As shown in FIG. 2, the stator core 200 is formed in an annular shape, and includes a yoke portion 211 extending in the circumferential direction of the stator 130 and a plurality of stator teeth 210 formed on the inner peripheral surface of the yoke portion 211. I have.

  Stator teeth 210 are formed so as to protrude from the inner peripheral surface of yoke portion 211 toward the radially inner side of stator 130. A plurality of stator teeth 210 are formed at intervals in the circumferential direction of the stator 130. Between the stator teeth 210, a slot portion 220 that accommodates the coil 132 is formed. A plurality of slits 131 are formed in the stator core 200 at intervals in the circumferential direction of the stator 130.

  FIG. 3 is a cross-sectional view showing in detail the permanent magnet 122 and a portion located around the permanent magnet 122. As shown in FIG. 3, the slit 131 is formed so as to communicate with the slot portion 220. And the slot part 220 in which the slit 131 was provided continuously, and the slot part 220 in which the slit 131 is not formed are alternately provided in the circumferential direction of the stator 130.

  The slit 131 is connected to an end portion located radially outward of the slot portion 220 and extends in the radial direction of the stator 130.

  Of the slit 131, the end portion on the radially outer side of the stator 130 does not reach the outer peripheral surface of the stator 130, and is positioned on the radially inner side with respect to the outer peripheral surface of the stator 130.

  Therefore, an outer peripheral side connection portion 213 is formed on the radially outer side with respect to the slit 131.

  Here, the circumferential width T2 of the stator 130 in the slit 131 is larger than the radial distance T1 of the stator 130 between the end face located on the radially inner side of the stator tooth 210 and the outer circumferential surface of the rotor 120. It is formed to be smaller. For example, the width T2 is formed to be about T1 / 10 to T1 / 5. The slit 131 extends in the central axis direction of the stator core 200 and extends so as to reach both end surfaces of the stator core 200 in the axial direction.

  FIG. 3 shows a magnetic flux circuit K1 defined by the magnetic fluxes MF1 and MF2 radiated from the permanent magnet 122A and a magnetic flux circuit K2 defined by the magnetic fluxes MF1 and MF2 radiated from the permanent magnet 122A. .

  Of the side surfaces of the permanent magnet 122A arranged in the radial direction of the rotor 120, the side surface located on the outer peripheral surface side of the rotor 120 is an N pole, and the side surface on the radially inner side is an S pole. ing.

  Here, the stator teeth 210E, 210D, 210C, 210B, and 210A are located on the radially outer side with respect to the permanent magnet 122A, and are sequentially arranged in the rotation direction P, respectively.

  The stator teeth 210E are located on the rear side in the rotational direction P with respect to the permanent magnets 122A, and the stator teeth 210D are located on the rear side in the rotational direction P with respect to the end portions on the rear side in the rotational direction P of the permanent magnets 122A. is doing. Furthermore, the stator teeth 210C are located on the front side in the rotational direction P with respect to the end portion on the rear side in the rotational direction P of the permanent magnet 122A. The stator teeth 210B are located on the front side in the rotational direction P rather than the end portion located on the front side in the rotational direction P of the permanent magnet 122A.

  At the timing shown in FIG. 3, some of the magnetic fluxes MF1 and MF2 out of the magnetic fluxes MF1 to MF4 radiated from the permanent magnet 122A pass through the magnetic flux circuit K1. The magnetic flux circuit K1 passes through the air gap GP from the surface of the rotor 120 and reaches the end face of the stator teeth 210B. Thereafter, the magnetic flux circuit K1 travels radially outward in the stator teeth 210B, reaches the yoke portion 211, and travels backward in the rotation direction P in the yoke portion 211. Further, the magnetic flux circuit K1 reaches the stator teeth 210E and advances in the stator teeth 210E radially inward. Thereafter, the magnetic flux circuit K1 reaches the surface of the rotor 120 from the end surface on the radially inner side of the stator teeth 210E over the air gap GP, and returns to the permanent magnet 122A.

  In the state shown in FIG. 3, stator teeth 210B are located in front of rotation direction P with respect to permanent magnet 122A. For this reason, in the process in which the magnetic flux MF1 and the magnetic flux MF2 pass through the magnetic flux circuit K1, the magnetic flux MF1 and the magnetic flux MF2 are inclined toward the front side in the rotational direction P from the surface of the rotor 120 toward the end face of the stator teeth 210B.

  Further, since the side surface of the permanent magnet 122A on the radially outer side is an N pole, when the magnetic flux MF1 and the magnetic flux MF2 enter the surface of the rotor 120 from the stator teeth 210E, the permanent magnet 122A is inclined rearward in the rotational direction P.

  For this reason, stress is applied to the rotor 120 so that the path length of the magnetic flux circuit K1 is shortened, and the rotor 120 rotates in the rotation direction P.

  When the magnetic flux MF2 flows in the magnetic flux circuit K1, the magnetic flux MF2 is divided into the slit 131B positioned between the stator teeth 210B and the stator teeth 210C, and the slit 131C positioned between the stator teeth 210D and the stator teeth 210E. To reach stator teeth 210E. Thereafter, the magnetic flux MF2 passes through the stator teeth 210E, the air gap GP, and the rotor 120, and returns to the permanent magnet 122A.

The magnetic flux MF1 passes through the radially outer side of the stator 130 with respect to the magnetic flux MF2, and the magnetic flux MF1.
Passes through the outer peripheral side connecting portion 213 located on the radially outer side with respect to the slit 131B and the slit 131C. Magnetic flux MF1 reaches stator teeth 210E, and then passes through stator teeth 210E, air gap GP and rotor 120, and returns to permanent magnet 122A.

  Here, the path length of the magnetic circuit through which the magnetic flux MF1 passes is longer than the path length of the magnetic circuit through which the magnetic flux MF2 passes. On the other hand, the magnetic flux MF1 does not pass through the slits 131B and 131C having a higher magnetic resistance than the outer peripheral side connection portion 213.

  For this reason, the resistance of the magnetic circuit through which the magnetic flux MF1 passes is substantially equal to the resistance of the magnetic circuit through which the magnetic flux MF2 passes.

  In the yoke part 211, the path length of each magnetic flux differs greatly between the magnetic flux passing through the radially inner side and the magnetic flux passing through the radially outer side. On the other hand, the magnetic flux passing through the radially outer side of the yoke portion 211 passes through the outer peripheral side connecting portion 213, while the magnetic flux passing through the radially inner side passes through the slit 131. For this reason, it can suppress that a big difference arises in the resistance of the magnetic circuit of the magnetic flux which passes a radial inner side, and the resistance of the magnetic circuit of the magnetic flux which passes a radial outer side.

  As a result, the magnetic flux that has entered the stator teeth 210 </ b> B is distributed substantially uniformly in the radial direction of the stator 130 in the yoke portion 211. Thereby, it can suppress that the part where magnetic flux density becomes high can be suppressed, and generation | occurrence | production of magnetic saturation can be suppressed.

  A slit 131B and a slit 131C are located in the magnetic flux circuit K1. Here, the total width of the width in the circumferential direction of the slit 131B and the width in the circumferential direction of the slit 131C is smaller than the width T1 of the air gap GP.

  As described above, since the widths of the slits 131B and 131C are narrowed, the formation of the slits 131B and 131C suppresses an increase in the resistance of the magnetic flux circuit K1, thereby reducing the flow of magnetic flux in the magnetic flux circuit K1. Can be secured.

  Among the magnetic fluxes radiated from the permanent magnet 122A, some of the magnetic fluxes MF3 and MF4 pass through the magnetic flux circuit K2.

  Here, the magnetic flux circuit K2 passes through the air gap GP from the surface of the rotor 120, reaches the end face of the stator teeth 210C, and advances the stator teeth 210C in the radial direction. Further, the magnetic flux circuit K2 reaches the yoke portion 211, proceeds in the yoke portion 211 toward the rear side in the rotation direction P, and reaches the stator teeth 210E. Thereafter, the magnetic flux circuit K2 proceeds radially inward in the stator teeth 210E, passes through the air gap GP, reaches the rotor 120, and returns to the permanent magnet 122A.

  When the magnetic fluxes MF3 and MF4 flow through the magnetic flux circuit K2, the magnetic flux MF4 passes through a portion of the stator core 200 that is located radially inward with respect to the magnetic flux MF3.

  On the other hand, both the magnetic flux MF3 and the magnetic flux MF4 pass radially inward with respect to the magnetic flux MF1 and the magnetic flux MF2. As a result, the magnetic fluxes MF3 and MF4 pass through a portion located on the radially inward side with respect to the radial central portion of the slit 131 and the vicinity thereof. For this reason, there is no significant difference between the path length of the magnetic circuit through which the magnetic flux MF3 passes and the path length of the magnetic circuit through which the magnetic flux MF4 passes.

  Since both the magnetic flux MF3 and the magnetic flux MF4 pass through the slit 131C, a large difference between the resistance of the magnetic circuit through which the magnetic flux MF3 passes and the resistance of the magnetic circuit through which the magnetic flux MF4 passes is suppressed.

  As a result, the magnetic flux entering from the stator teeth 210 </ b> C is also distributed substantially uniformly in the radial direction within the yoke portion 211.

  As described above, the magnetic fluxes MF1 to MF4 from the permanent magnet 122A are distributed substantially uniformly in the radial direction in the yoke portion 211. Thereby, in stator core 200, it can control that the field where magnetic flux density becomes high arises, and generation of magnetic saturation can be controlled.

  Here, in the example shown in FIG. 2 and FIG. 3, the width of the slit 131 is substantially constant from the radially inner end to the radially outer end. However, it is not limited to this.

  FIG. 4 is a cross-sectional view showing a modification of rotating electric machine 100 according to the first embodiment. In the example shown in FIG. 4, the slit 131 is formed so that the width T2 becomes smaller from the radially inner side toward the radially outer side.

  Here, the path length of the magnetic circuit passing through the slit 131 gradually increases from the radially inner side toward the radially outer side.

  Therefore, by increasing the width of the slit 131 from the radially outer side toward the radially inner side, the slit 131 extends from the radially outer end to the radially inner end of the slit 131. The magnetic resistance of the magnetic circuit passing through 131 can be made uniform.

(Embodiment 2)
A rotating electrical machine 100 according to Embodiment 2 of the present invention will be described with reference to FIGS. 5 and 6. Of the configurations shown in FIG. 5 and FIG. 6, the same or corresponding components as those shown in FIG. 1 to FIG. . FIG. 5 is a cross-sectional view of the rotating electrical machine 100 according to Embodiment 2, and FIG. 6 is an enlarged cross-sectional view of a part of the rotating electrical machine 100 shown in FIG.

  As shown in FIGS. 5 and 6, the stator core 200 includes a plurality of divided stator cores 250 arranged in an annular shape, and a cylindrical fixing member 146 attached to the outer peripheral side of the divided stator core 250.

  The fixing member 146 is press-fitted or shrink-fitted to the outer peripheral side of the divided stator core 250 arranged in an annular shape. The fixing member 146 fixes the divided stator cores 250 in an annular arrangement by pressing the outer peripheral surface of each divided stator core 250 toward the radially inner side.

  The divided stator core 250 includes a divided yoke portion 251 that extends in the circumferential direction of the stator 130, and a stator tooth 210 that is formed on the inner circumferential surface of the divided yoke portion 251 and projects radially inward. .

  Each divided stator core 250 is formed with two (a plurality of) stator teeth 210 at intervals in the circumferential direction of the stator 130, and a slot portion 220 is formed between the stator teeth 210. Slot portions 220 are also formed between the stator teeth 210 of the divided stator cores 250 adjacent in the circumferential direction.

  Here, of the peripheral surfaces of each divided stator core 250, concave portions 149 are formed on the side surfaces arranged in the circumferential direction of the stator 130. The recessed portion 149 extends from the radially inner end of the side surface of the divided yoke portion 251 toward the radially outer side.

  The recess 149 does not reach the outer peripheral surface located on the radially outer side of the divided stator core 250, but is located on the radially inner side with respect to the outer peripheral surface. Thus, an outer peripheral side protruding portion 147 that protrudes in the circumferential direction of the stator 130 is formed in a portion of the side surface of the divided stator core 250 that is located on the radially outer side with respect to the concave portion 149.

  The outer peripheral protrusion 147 of the split stator core 250 is in contact with the outer peripheral protrusion 147 of another split stator core 250 adjacent in the circumferential direction.

  And the outer peripheral side connection part 213 is formed because the end surfaces of the outer peripheral side protrusion part 147 of the division | segmentation stator core 250 adjacent to the circumferential direction contact | abut.

  On the other hand, the recess 149 of the split stator core 250 forms a slit 131 in cooperation with the recess 149 of another split stator core 250 adjacent in the circumferential direction. In other words, the slit 131 is formed by the recesses 149 facing each other. Thus, in the rotary electric machine 100 according to the second embodiment, the slits 131 are formed by forming the recesses 149 on the side surfaces of the respective divided stator cores 250 and arranging the recesses 149 in the circumferential direction. The slit 131 is also connected to the end portion on the radially outer side of the slot portion 220 in the same manner as the rotary electric machine 100 according to the first embodiment.

  As described above, in the rotating electrical machine 100 according to the second embodiment, similarly to the rotating electrical machine 100 according to the first embodiment, the magnetic flux radiated from the permanent magnet 122 and entering the stator core 200 is substantially reduced in the radial direction. It is possible to distribute evenly and suppress the occurrence of magnetic saturation.

  FIG. 7 is a cross-sectional view showing a part of a rotating electrical machine of a comparative example. Also in the configuration of the rotating electrical machine according to the comparative example shown in FIG. 7, the same or corresponding components as those shown in FIGS. 1 to 6 are designated by the same reference numerals and the description thereof is omitted. There is a case.

  The stator core 200 of the rotating electrical machine shown in FIG. 7 is also formed by arranging a plurality of divided stator cores 250 in an annular shape. A concave portion 149 is formed on the side surface of each divided stator core 250. The recess 149 extends radially inward from the outer peripheral surface of the divided stator core 250, and protrudes toward the circumferential direction of the stator 130 at a portion adjacent to the recess 149 on the radially inner side. An inner peripheral protrusion 148 is formed.

  The slits 131 are formed by arranging the concave portions 149 of the two adjacent divided stator cores 250 in the circumferential direction, and the inner peripheral protrusions 148 formed in the two adjacent divided stator cores 250 are in contact with each other. An inner peripheral side connection portion 214 is formed.

  Thus, in the rotating electrical machine according to the comparative example, the inner peripheral side connection portion 214 is formed on the inner peripheral side of the stator core 200, and the slit is formed on the radially outer side with respect to the inner peripheral side connection portion 214. 131 is formed.

  The magnetic circuit that passes through the inner peripheral side of the stator core and passes through the inner peripheral side connection portion 214 has a shorter path length than the magnetic circuit that passes through the outer peripheral side of the stator core and passes through the slit 131. The inner peripheral side connection portion 214 has a smaller magnetic resistance than the slit 131. For this reason, the resistance of the magnetic circuit passing through the inner peripheral side connection portion 214 is much smaller than that of the magnetic circuit passing through the slit 131.

  Thereby, in the rotating electrical machine according to the comparative example, the magnetic fluxes MF1 and MF2 that enter the stator core 200 from the stator teeth 210B and the magnetic fluxes MF3 and MF4 that enter the stator core 200 from the stator teeth 210C are both connected on the inner circumference side. Pass through section 214. For this reason, the magnetic flux density in the inner periphery side connection part 214 becomes high.

  On the other hand, in the present embodiment shown in FIG. 6 described above, the magnetic fluxes MF1 to MF4 that have entered the stator core 200 are distributed substantially evenly in the radial direction of the stator core 200, and the magnetic flux density is increased at specific portions. It is suppressed.

  FIG. 8 is a graph showing the iron loss of the rotating electrical machine 100 according to the second embodiment and the iron loss of the rotating electrical machine according to the comparative example. As shown in FIG. 8, it can be seen that the iron loss of the rotating electrical machine according to the second embodiment is lower than the iron loss of the rotating electrical machine of the comparative example.

  In the rotating electrical machine according to the comparative example, the outer circumferential surface on the radially outer side of each divided stator core 250 is fixed by a fixing member 146, and the side surface on the radially inner side of each divided stator core 250 is the inner side. They are fixed to each other by the circumferential protrusion 148.

  On the other hand, in the rotating electrical machine 100 according to the second embodiment, each stator core 200 has an outer circumferential surface on the radially outer side fixed by a fixing member 146, while the stator core 200 has a radially inner side. The side surfaces are separated from each other.

  For this reason, the rigidity of the stator core 200 of the rotating electrical machine 100 according to Embodiment 2 is smaller than the rigidity of the stator core 200 of the rotating electrical machine according to the comparative example.

  Here, as for the rotating electrical machine according to the comparative example and the rotating electrical machine according to the second embodiment, as a result of investigating the transmission of vibrations to the stator core outer peripheral surface when hammering the stator core inner peripheral surface, It has been found that the rotating electrical machine of the second embodiment is less likely to resonate.

  FIG. 9 shows the results of investigating the transmission of vibrations to the outer peripheral surface of the stator core when hammering the inner peripheral surface of the stator core in the rotating electrical machine according to the comparative example. In FIG. 9, the horizontal axis represents the vibration frequency, and the vertical axis represents vibration acceleration generated in the radial direction of the stator.

  FIG. 10 shows a result of investigating transmission of vibration to the stator core outer peripheral surface when hammering the inner peripheral surface of the stator core in the rotating electrical machine according to the second embodiment. In FIG. 10, the horizontal axis represents the vibration frequency, and the vertical axis represents the vibration acceleration generated in the radial direction of the stator.

  As shown in FIGS. 9 and 10, it can be seen that the number of resonance points generated in the stator of the rotating electrical machine 100 according to the second embodiment is smaller than the number of resonance points generated in the stator of the rotating electrical machine according to the comparative example. . Furthermore, it can be seen that the peak generated in the stator of the rotating electrical machine 100 according to the second embodiment is smaller than the peak generated in the stator of the rotating electrical machine according to the comparative example.

  That is, it can be seen that the rotating electrical machine according to the second embodiment can reduce noise due to resonance more than the rotating electrical machine according to the comparative example.

  That is, it can be seen that the vibration generated in the rotating electrical machine according to the second embodiment is reduced more than the vibration generated in the rotating electrical machine according to the comparative example, and noise can be reduced.

(Embodiment 3)
A rotating electrical machine 100 according to Embodiment 3 of the present invention will be described with reference to FIGS. 11 to 13. Of the configurations shown in FIGS. 11 to 13, the same or corresponding components as those shown in FIGS. 1 to 10 are denoted by the same reference numerals and description thereof may be omitted. is there.

  FIG. 11 is a cross-sectional view of the rotating electrical machine 100 according to the third embodiment, and FIG. 12 is a cross-sectional view in which a part of the rotating electrical machine shown in FIG. 11 is enlarged.

  As shown in FIGS. 11 and 12, the stator core 200 includes a plurality of divided stator cores 250 arranged in an annular shape.

  Each divided stator core 250 includes a divided yoke portion 251 that extends in the circumferential direction of the stator core 200 and a stator tooth 210 that protrudes radially inward from the inner peripheral surface of the divided yoke portion 251.

  Out of the surface of the divided yoke portion 251, an outer peripheral side protruding portion 147 that protrudes toward the circumferential direction of the stator core 200 and an inner peripheral side protruding portion 148 are formed on the side surface arranged in the circumferential direction of the stator core 200. ing.

  The outer peripheral side protruding portion 147 is formed on a side portion of the side surface of the divided yoke portion 251 that is located on the radially outer side of the stator core 200. The inner peripheral side protruding portion 148 is formed on a side portion of the side surface of the divided yoke portion 251 that is located on the radially inner side of the stator core 200.

  On the other hand, a concave portion 149 is formed in the radial center portion of the side surface of the split stator core 250. The concave portion 149 is located between the outer peripheral side protruding portion 147 and the inner peripheral side protruding portion 148.

  In other words, the outer peripheral protrusion 147 is located on the radially outer side with respect to the recess 149, and the inner peripheral protrusion 148 is located on the radially inner side with respect to the recess 149. .

  And the outer peripheral side protrusion part 147 formed in the division | segmentation stator core 250 adjacent to the circumferential direction of the stator core 200 contact | abuts, and the outer peripheral side connection part 213 is formed. Furthermore, the inner peripheral side protrusions 148 are in contact with each other to form an inner peripheral side connection portion 214.

  Further, the slits 131 are formed by arranging the concave portions 149 of the adjacent divided stator cores 250 in the circumferential direction of the stator core 200.

  Thus, the stator core 200 of the rotating electrical machine 100 according to the third embodiment is formed with a plurality of slits 131 spaced in the circumferential direction.

  Here, the width T3 of the inner peripheral side protruding portion 148 (inner peripheral side connecting portion 214) in the radial direction of the stator core 200 is formed to be narrower than the width T4 of the outer peripheral side protruding portion 147 (outer peripheral side connecting portion 213). Has been. Both the inner peripheral protrusion 148 and the outer peripheral protrusion 147 extend in the central axis direction of the stator core 200. And both the inner peripheral side protrusion part 148 and the outer peripheral side protrusion part 147 are extended so that the axial direction both end surfaces of the stator core 200 may be reached.

  For this reason, the cross-sectional area of the cross section along the radial direction of the inner peripheral side connection portion 214 is smaller than the cross sectional area S4 of the outer peripheral side connection portion 213 along the radial direction of the stator core 200. Accordingly, the resistance when the magnetic flux passes through the outer peripheral side connection portion 213 is smaller than the resistance when the magnetic flux passes through the inner peripheral side connection portion 214.

  Here, the magnetic flux MF1 entering the stator core 200 from the stator teeth 210B passes through, for example, the outer peripheral side connecting portion 213 and returns from the stator teeth 210E to the rotor 120. The magnetic flux MF2 passes on the radially inner side of the stator core 200 with respect to the magnetic flux MF1. The magnetic flux MF2 passes through the slit 131, reaches the stator teeth 210E, and returns to the rotor 120 from the end face of the stator teeth 210E.

  Here, the path length of the magnetic circuit through which the magnetic flux MF1 passes is longer than the magnetic circuit through which the magnetic flux MF2 passes. On the other hand, while passing through the slit 131 in the magnetic circuit through which the magnetic flux MF2 passes, the outer peripheral side connection part 213 having a resistance smaller than that of the slit 131 is located in the magnetic circuit through which the magnetic flux MF1 passes.

  For this reason, as a result, the resistance is substantially equal between the magnetic circuit through which the magnetic flux MF1 passes and the magnetic circuit through which the magnetic flux MF2 passes.

  Here, the inner peripheral side connection portion 214 is formed so as to be narrower than the outer peripheral side connection portion 213. On the other hand, the path length of the magnetic circuit passing through the inner peripheral side connection portion 214 is shorter than the path length of the magnetic path passing through the outer peripheral side connection portion 213.

  For this reason, the resistance of the magnetic path passing through the inner peripheral side connection portion 214 and the magnetic path passing through the outer peripheral side connection portion 213 are substantially equal.

  Thus, the resistance of the magnetic circuit passing through the inner peripheral side connection portion 214, the resistance of the magnetic circuit 131 passing through the outer peripheral side connection portion 213, and the resistance of the magnetic circuit passing through the slit 131 are all equal or approximate. is doing.

  For this reason, the magnetic flux entering from the stator teeth 210 is distributed substantially uniformly in the radial direction in the stator core 200. Thereby, in the stator core 200, it can suppress that magnetic flux concentrates and magnetic saturation arises.

  Here, for example, the magnetic flux path MF2 enters the stator core 200 from the stator teeth 210B and passes through the plurality of slits 131 until it enters the rotor 120 from the stator teeth 210E.

  The total width of the slits 131 through which the magnetic flux path MF2 passes is smaller than the width of the air gap GP. For this reason, the resistance by the slit 131 is kept small, and the magnetic flux can flow satisfactorily.

  In the third embodiment, the stator core 200 constituted by the divided stator core 250 has been described. However, the stator core 200 is not limited to this, and may be a stator core integrally formed in the circumferential direction as shown in FIG. .

  In the stator core 200 shown in FIG. 13, the cross-sectional area S4 of the outer peripheral side connection portion 213 is formed to be larger than the cross-sectional area S3 of the inner peripheral side connection portion 214. Therefore, also in the example shown in FIG. 13, the magnetic flux extending in the circumferential direction in the yoke portion 211 of the stator core 200 is distributed in the radial direction in the radial direction of the stator core 200, and saturation of the magnetic flux can be suppressed. .

  FIG. 14 is a cross-sectional view showing a second modification of rotating electrical machine 100 according to the third embodiment. As shown in FIG. 14, the width of the slit 131 is formed so as to increase from the radially outer side of the stator core 200 toward the radially inner side.

  Here, for example, a magnetic circuit passing through the radially inner side of the slit 131 has a short path length, but passes through a wide portion of the slit 131.

  On the other hand, the magnetic circuit passing through the outer side in the radial direction of the slit 131 has a long path length, but passes through a portion where the width of the slit 131 is narrow. For this reason, the resistance of the magnetic circuit passing through the slit 131 can be made substantially uniform from the radially inner end of the slit 131 to the radially outer end.

  As a result, the magnetic flux density in the stator core 200 can be made uniform, and the occurrence of magnetic flux saturation can be suppressed.

  Although the embodiment of the present invention has been described above, it should be considered that the embodiment disclosed this time is illustrative and not restrictive in all respects. 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. Furthermore, the above numerical values are examples, and are not limited to the above numerical values and ranges.

  The present invention is suitable for a stator core and a rotating electric machine.

It is a sectional side view of the rotary electric machine which concerns on Embodiment 1 of this invention. It is sectional drawing in the II-II line of FIG. It is sectional drawing which shows a permanent magnet and the part located in the circumference | surroundings in detail. It is sectional drawing which shows the modification of the rotary electric machine which concerns on this Embodiment 1. FIG. It is sectional drawing of the rotary electric machine which concerns on this Embodiment 2. FIG. FIG. 6 is an enlarged cross-sectional view of a part of the rotating electrical machine shown in FIG. 5. It is sectional drawing which shows a part of rotary electric machine of a comparative example. It is a graph which shows the iron loss of the rotary electric machine which concerns on this Embodiment 2, and the iron loss of the rotary electric machine which concerns on a comparative example. It is a graph which shows the vibration which arises in the stator of the rotary electric machine which concerns on the said comparative example. 6 is a graph showing vibrations generated in the rotating electrical machine stator according to Embodiment 2. It is sectional drawing of the rotary electric machine which concerns on this Embodiment 3. FIG. FIG. 12 is an enlarged cross-sectional view of a part of the rotating electrical machine illustrated in FIG. 11. It is sectional drawing which shows the modification of the rotary electric machine which concerns on this Embodiment 3. FIG. It is sectional drawing which shows the 2nd modification of the rotary electric machine which concerns on this Embodiment 3. FIG.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 100 Rotating electrical machine, 110 Rotating shaft, 120 Rotor, 121 Rotor core, 122 Permanent magnet, 124 Resin, 126 Permanent magnet insertion hole, 130 Stator, 131 Slit, 132 Coil, 146 Fixing member, 147 Outer peripheral side protrusion, 148 Inner peripheral side Protruding part, 149 recessed part, 200 stator core, MF1, MF2 magnetic flux.

Claims (9)

A stator core formed in an annular shape,
A plurality of slit portions are formed in the stator core at intervals in the circumferential direction of the stator core,
A first connecting portion formed in a portion located on the radially inner side of the stator core with respect to the slit portion;
A second connecting portion formed on a portion located on the outer side of the radial direction with respect to the slit portion;
The stator core, wherein a cross-sectional area of a cross section of the first connection portion along a radial direction of the stator core is smaller than a cross-sectional area of a cross section of the second connection portion along the radial direction.   2. The stator core according to claim 1, wherein a width of the slit portion in the circumferential direction decreases from a radially inner side of the stator core toward a radially outer side. The stator core includes a plurality of divided stator cores arranged in an annular shape,
The split stator core includes a split yoke portion extending in the circumferential direction,
Of the peripheral surfaces of the divided yoke portions, concave portions are formed on the side surfaces arranged in the circumferential direction,
Of the side surface of the divided yoke portion, an inner peripheral side protruding portion that protrudes in the circumferential direction of the stator core is formed in a portion adjacent to the concave portion on the radially inner side of the stator core,
Of the side surface of the divided yoke portion, an outer peripheral side protruding portion that protrudes in the circumferential direction of the stator core is formed in a portion adjacent to the concave portion on the radially outer side of the stator core,
The slit portion is formed by arranging the concave portions formed in the divided stator cores adjacent to each other in the circumferential direction in the circumferential direction.
The first connection portion is formed by the inner peripheral protrusions formed on the split stator cores adjacent in the circumferential direction abutting each other,
3. The stator core according to claim 1, wherein the second connection portion is formed by the outer peripheral side protruding portions formed on the divided stator cores adjacent in the circumferential direction contacting each other.   The rotary electric machine provided with the stator core in any one of Claims 1-3. An annular stator including a stator core and a coil attached to the stator core;
A rotor core inserted into the stator and rotatably supported, and a rotor including a magnet provided on the rotor core;
With
The stator core is provided with a plurality of slit portions provided at intervals in the circumferential direction and extending in the radial direction,
Magnetic flux radiated from the magnet reaches the stator from the rotor, passes through the stator, passes through a magnetic circuit reaching the rotor from the stator,
A rotating electrical machine in which a total width of the circumferential widths of the slit portions located in the magnetic circuit is smaller than a gap between the rotor and the stator teeth. The stator core includes a yoke portion extending in the circumferential direction of the stator, and a stator tooth extending from the yoke portion toward the radially inner side of the stator,
A plurality of the stator teeth are formed at intervals in the circumferential direction, and a slot portion capable of accommodating the coil is formed between the stator teeth.
The rotating electrical machine according to claim 5, wherein the slit portion reaches the slot portion. The stator core includes a yoke portion extending in the circumferential direction of the stator, and a stator tooth extending from the yoke portion toward the radially inner side of the stator,
A plurality of the stator teeth are formed at intervals in the circumferential direction, and a slot portion capable of accommodating the coil is formed between the stator teeth.
The rotating electrical machine according to claim 5, wherein the slit portion is located on an outer side in the radial direction with respect to the slot portion.   Among the slit portions, the distance between the radially outer end portion and the outer peripheral surface of the stator core is a portion located at the radially inner end portion and the radial direction of the slot portion. The rotating electrical machine according to claim 7, wherein the rotating electrical machine is longer than a distance from a portion located at an outer side end portion of the rotating electrical machine.   9. The rotating electrical machine according to claim 5, wherein a width of the slit portion in the circumferential direction decreases from a radially inner side to a radially outer side of the stator core.

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