JP2018137968A - Rotary electric machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a rotary electric machine 1 that hinders a magnetic force decrease of a permanent magnet 31 due to eddy current.SOLUTION: In a rotary electric machine 1 of radial gap type, comprising a rotor 3 and a stator 4, the rotor 3 comprises: a plurality of permanent magnets 31 having magnet arcuate faces 31c opposite the stator 4; and a rotor core 32 holding the plurality of permanent magnets 31. The magnet arcuate face 31c of each permanent magnet 31 is formed in an arcuate shape in cross-section so as to have a radius r smaller than a radius R of a virtual circle VC along an outer peripheral surface of the rotor 3 in a cross-section along a radial direction of the rotor 3. The rotor core 32 comprises: a flat portion 321a abutting on a magnet flat surface 31b of each permanent magnet 31 disposed on the virtual circle VC such that the tops of magnet arcuate faces 31c substantially coincide; and a plurality of locking parts 322 projecting radially outside from between circumferentially adjacent flat portions 321a and the respective peripheral surfaces 322a of which form an outer peripheral surface of the rotor core 32.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a rotary electric machine of a radial gap type in which, for example, a rotor and a stator are opposed to each other in the radial direction of a rotating shaft, and used as a motor, a generator, or a motor / generator.

As a rotating electric machine such as a motor, a generator, or a motor / generator, there is a radial gap type rotating electric machine in which a rotor and a stator are arranged to face each other via an air gap in a radial direction of a rotating shaft (Patent Document 1). reference).
In such a radial gap type rotating electrical machine, as the permanent magnet is brought closer to the stator, the performance thereof, in particular, the axial torque generated in the rotating shaft can be improved.

  For example, in the rotor (rotor) described in Patent Document 1, a magnet insertion hole into which a permanent magnet is inserted is formed in the vicinity of the outer periphery of the rotor core (rotor core). Thereby, since patent document 1 can make a permanent magnet adjoin to a stator, it is supposed that the performance of a rotary electric machine can be improved.

  By the way, in order to facilitate positioning in the magnet insertion hole, the permanent magnet of Patent Document 1 is formed in a substantially cross-sectional shape that is curved so that a facing surface facing the stator protrudes radially outward.

  In such a rotating electrical machine having a substantially saddle-shaped permanent magnet, when the rotor starts to rotate, an application is made that an eddy current E is generated in the vicinity of the top of the facing surface 61 of the permanent magnet 60 as shown in FIG. Has been confirmed by people.

  When such an eddy current is generated, the vicinity of the top portion of the facing surface of the permanent magnet generates heat due to the eddy current, and the temperature becomes higher than other portions of the permanent magnet. For this reason, when the rotor rotates, the magnetic force of the permanent magnet decreases due to heat generated by the eddy current, and the desired shaft torque may not be obtained.

JP 2007-49803 A

  In view of the above problems, an object of the present invention is to provide a rotating electrical machine that can suppress a decrease in magnetic force of a permanent magnet due to eddy current.

  The present invention provides a radial gap that is provided integrally with a rotating shaft, and that includes a rotor having a substantially circular outer circumferential shape when viewed from the axial direction of the rotating shaft, and a stator that is supported so as not to rotate. A rotary electric machine of the type, wherein the rotor includes a plurality of permanent magnets having opposing surfaces facing the stator, and a rotor core holding the plurality of permanent magnets arranged along a circumferential direction of the rotor. The opposing surface of the permanent magnet is formed in a cross-sectional arc shape having a radius smaller than the radius of a virtual circle along the outer peripheral surface of the rotor in a cross-section along the radial direction of the rotor; The abutment surface that contacts the radially inner surface of the permanent magnet disposed substantially coincident with the top of the opposing surface on the virtual circle, and the contact surface that is adjacent in the circumferential direction is between the contact surface. Radially outside Both projecting towards, characterized in that a plurality of protrusions the distal end surface forms the outer peripheral surface of the rotor core.

The rotating electrical machine may be a motor, a generator, or a motor / generator.
According to the present invention, it is possible to suppress a decrease in the magnetic force of the permanent magnet due to the eddy current.
Specifically, since the top of the permanent magnet substantially coincides with the virtual circle along the outer peripheral surface of the rotor, that is, the virtual circle along the tip surface of the protrusion in the rotor core, the gap between the stator and the rotor The air gap is minimum at the protrusion of the rotor core and the top of the permanent magnet.

  Furthermore, since the opposing surface of the permanent magnet is formed with a radius smaller than the radius of the virtual circle, the air gap between the stator and the permanent magnet gradually increases from the top of the permanent magnet to the end of the permanent magnet in the circumferential direction. It becomes larger and becomes the maximum at the end of the permanent magnet in the circumferential direction.

For this reason, in the rotating electrical machine, portions where the air gap is minimum and portions where the air gap is larger than the portion where the air gap is minimum are alternately formed in the circumferential direction.
In the rotating electrical machine having such an air gap, when the rotor starts to rotate, the air in the air gap starts to flow due to the shearing force due to the rotation of the rotor.

  At this time, in the air gap, between the virtual circle and the stator, in the range surrounded by the air flow flowing in the rotation direction of the rotor, the virtual circle, the opposed surface of the permanent magnet, and the protrusion of the rotor core And a flow of air flowing in a swirling manner.

  For this reason, the flow of air between the virtual circle and the stator is a flow that is relatively faster than the flow velocity of the air flowing in the range surrounded by the virtual circle, the opposing surface of the permanent magnet, and the protrusion of the rotor core. .

  Furthermore, since the air in the range surrounded by the virtual circle, the opposing surface of the permanent magnet, and the protrusion of the rotor core is in contact with the vicinity of the end of the permanent magnet in the circumferential direction, the temperature is unlikely to be high. For this reason, the rotating electrical machine can join relatively low-temperature air to the air flow flowing between the virtual circle and the stator.

  As a result, the rotating electrical machine can increase the flow rate of the air flowing through the gap between the top of the permanent magnet and the stator and lower the temperature compared to the rotating electrical machine having a uniform air gap.

For this reason, the rotating electrical machine can efficiently air-cool the vicinity of the top of the opposing surface of the permanent magnet, and can suppress the temperature in the vicinity of the top of the permanent magnet from rising due to the eddy current.
Therefore, the rotating electrical machine can suppress a decrease in the magnetic force of the permanent magnet due to the eddy current.

  As an aspect of the present invention, the projecting portion of the rotor core extends from the radially outer end portion toward the circumferential direction, near the end portion of the facing surface in the circumferential direction, and the radial direction The contact part which contact | abuts is provided.

According to the present invention, the rotating electrical machine can reliably hold the permanent magnet having a part of the opposed surface exposed to the air gap with the rotor core.
Thereby, when the rotor starts to rotate, the rotating electrical machine can restrict the movement of the permanent magnet to the outside in the radial direction due to the centrifugal force, and can secure a stable air gap.

For this reason, the rotating electrical machine can flow air with a stable flow rate in the gap between the top of the permanent magnet and the stator.
Therefore, the rotating electrical machine can reliably hold the permanent magnet disposed close to the stator and can suppress a decrease in magnetic force of the permanent magnet.

  According to the present invention, it is possible to provide a rotating electrical machine that can suppress a decrease in magnetic force of a permanent magnet due to an eddy current.

The front view which shows the rotary electric machine in an axial view. The front view which shows the structure per pole in a rotary electric machine. Sectional drawing which shows the cross-sectional shape of the rotor per pole in a radial direction cross section. Sectional drawing which shows the cross-sectional shape of the permanent magnet in a radial direction cross section. Sectional drawing which shows the cross-sectional shape of the rotor core in a radial direction cross section. Explanatory drawing explaining the flow of the air in the air gap in a comparative example. Explanatory drawing explaining the flow of the air in the air gap in this embodiment. Explanatory drawing explaining the surface temperature of the permanent magnet in this embodiment. Explanatory drawing explaining the surface temperature of the permanent magnet from which the magnitude | size of a magnet circular arc surface differs. The perspective view which shows the flow of the eddy current in the permanent magnet of cross-sectional substantially saddle shape.

An embodiment of the present invention will be described below with reference to the drawings.
1 shows a front view of the rotating electrical machine 1 as viewed in the axial direction, FIG. 2 shows a front view per pole in the rotating electrical machine 1, and FIG. 3 is a cross-sectional view of the rotor 3 per pole in the radial section. 4 shows a cross-sectional view of the permanent magnet 31 in the radial cross section, and FIG. 5 shows a cross-sectional view of the rotor core 32 in the radial cross section.
Further, in FIG. 1, the housing 5 is shown in a cross section for clarity of illustration.

As shown in FIG. 1, the rotating electrical machine 1 according to the present embodiment is a radial gap type motor having, for example, 16 poles and 24 slots, and is provided integrally with the rotating shaft 2 and the rotating shaft 2. The outer peripheral shape seen from the axial direction is comprised of a substantially circular rotor 3, a substantially annular stator 4 disposed on the radially outer side of the rotor 3, and a substantially cylindrical housing 5 that accommodates and holds them. Yes.
As shown in FIG. 1, the rotating electrical machine 1 includes a rotating shaft 2, a rotor 3, a stator 4, and a housing 5 that are coaxially arranged when viewed from the axial direction of the rotating shaft 2.

  As shown in FIG. 1, the rotating shaft 2 has a substantially cylindrical shape extending in a predetermined direction, and is rotatably supported by the housing 5 via a bearing (not shown). The rotating shaft 2 is provided with a flange portion 2 a that restricts the movement of the rotor 3 in the axial direction of the rotating shaft 2.

As shown in FIGS. 1 and 2, the rotor 3 is composed of 16 permanent magnets 31 and a rotor core 32 in which the permanent magnets 31 are arranged in the vicinity of the outer periphery, and a part of the permanent magnets 31 serves as an air gap. Exposed inset rotor.
In addition, since the structure per pole in the rotor 3 will be described in detail later, it will be briefly described here.

  In the 16 permanent magnets 31, in the radial direction of the rotor 3, a permanent magnet whose radially outer polarity is an S pole and a permanent magnet whose radially outer polarity is an N pole are arranged in the circumferential direction of the rotor core 32. Alternatingly arranged along.

  As shown in FIGS. 1 and 2, the rotor core 32 has 16 magnet mounting portions on which a permanent magnet 31 is fitted and mounted on a substantially circular columnar body as viewed in the axial direction, along the circumferential direction. An opening is formed at a position in the vicinity of the outer periphery that is spaced apart. In addition, the rotor core 32 is comprised by the laminated body which laminated | stacked the thin plate material made from an electromagnetic steel plate in which the opening used as a magnet mounting part was formed previously in the axial direction.

The stator 4 includes a stator core 41 and a winding 42 wound around the stator core 41 as shown in FIGS.
As shown in FIG. 2, the stator core 41 is a laminated body in which thin sheets made of electromagnetic steel plates are laminated in the axial direction. The stator core 41 has a substantially annular back yoke portion 41 a as viewed in the axial direction, and 24 protruding from the back yoke portion 41 a. The teeth portions 41b are integrally formed.

The back yoke portion 41a is formed in an axial view annular shape having an outer diameter that forms the outer peripheral surface of the stator 4 when viewed in the axial direction.
The teeth portion 41 b is formed to protrude from the inner peripheral surface of the back yoke portion 41 a by a predetermined length toward the axial center of the stator 4 with a predetermined interval in the circumferential direction of the back yoke portion 41 a.

  The winding 42 is a conductive copper wire or the like, and is wound around the teeth portion 41 b of the stator core 41 with a predetermined number of turns. The end of the winding 42 is electrically connected to a terminal (not shown) that receives external power supply.

  Further, as shown in FIG. 1, the housing 5 is a housing body having a substantially cylindrical main body larger in diameter than the stator 4, and holds the stator 4 in a non-rotatable manner and allows the rotating shaft 2 to rotate freely. It is comprised so that it may support.

In such a rotating electrical machine 1, the configuration of the rotor 3 per pole will be specifically described.
As shown in FIGS. 2 and 3, the configuration of the rotor 3 per pole is composed of one permanent magnet 31 and one magnet mounting portion to which the permanent magnet 31 is fixed via an adhesive (not shown). It is configured.

  The permanent magnet 31 is a magnet that has been surface treated by grain boundary diffusion to prevent demagnetization. As shown in FIGS. 3 and 4, the permanent magnet 31 has a cross-sectional shape that is substantially saddle-shaped in cross section along the radial direction, and has a substantially cross-sectional shape that extends a predetermined length in the axial direction of the rotary shaft 2. It is formed in the shape.

  More specifically, as shown in FIG. 3 and FIG. 4, the permanent magnet 31 has a substantially arc-shaped surface on the radially outer side of a substantially rectangular cross section that is long in the orthogonal direction perpendicular to the radial direction. The cross section is formed in a substantially bowl shape.

  In the cross section along the radial direction, the surfaces of the permanent magnets 31 facing in the orthogonal direction are a pair of magnet side surfaces 31a, and the surface along the orthogonal direction connecting the magnet side surfaces 31a on the radial inner side is a magnet plane 31b. A substantially arc-shaped surface facing the magnet flat surface 31b on the radially outer side and facing the stator 4 is a magnet arc surface 31c, and the boundary between the magnet arc surface 31c and the magnet side surface 31a is chamfered with a predetermined radius. The portion is a chamfered portion 31d.

  Then, a virtual circle having a radius R as a linear distance from the center in the radial direction of the rotor core 32 to the outer peripheral surface of the rotor core 32 (an outer peripheral surface 322a of a locking portion 322 described later) is defined as a virtual circle VC. In this case, the magnet arc surface 31c of the permanent magnet 31 has a circular arc shape with a radius r smaller than the radius R of the virtual circle VC and a position different from the center of the virtual circle VC as shown in FIG. Is formed. In other words, the radius r of the magnet arc surface 31c is set to a value within a predetermined range in which the ratio of the virtual circle VC to the radius R is less than “1.0”.

  On the other hand, as shown in FIGS. 3 and 5, the rotor core 32 protrudes radially outward from the core base portion 321 with which the magnet plane 31 b of the permanent magnet 31 contacts, and the permanent magnet 31 is locked. The sixteen locking portions 322 are integrally formed.

  As shown in FIG. 5, the core base portion 321 has 16 plane portions 321 a having a length in the orthogonal direction substantially the same as the magnet plane 31 b of the permanent magnet 31 in the cross section along the radial direction, and from the virtual circle VC. Are formed in a polygonal shape in the axial direction inscribed in a circle with a small radius.

The planar portion 321a of the core base 321 has a radial length H1 from the intersection of a virtual line and a virtual circle VC along the radial direction substantially in the center in the orthogonal direction in a cross section along the radial direction. 31 is formed at a position substantially equal to the length H2 (see FIG. 4) from the top of the magnet arc surface 31c to the magnet plane 31b.
That is, the planar portion 321a of the core base 321 is formed such that when the permanent magnet 31 is mounted, the top of the permanent magnet 31 on the magnet arc surface 31c is positioned on the virtual circle VC.

  As shown in FIGS. 3 and 5, the locking portion 322 has a cross section extending substantially radially outward from between the planar portions 321 a of the core base portion 321 adjacent in the circumferential direction in the cross section along the radial direction. It is formed in a T shape.

  As shown in FIG. 5, the engaging portion 322 has an arcuate shape with a radius R in which the outer peripheral surface 322 a facing the stator 4 on the outer side in the radial direction becomes a surface along the virtual circle VC in the cross section along the radial direction. Is formed.

  More specifically, as shown in FIGS. 3 and 5, the locking portion 322 includes a circumferential restriction portion 323 that restricts the movement of the permanent magnet 31 in the circumferential direction and a radial direction in a cross section along the radial direction. The permanent magnet 31 is formed in a substantially T-shaped cross section by a radial direction regulating portion 324 that regulates the movement of the permanent magnet 31 with the core base 321.

  As shown in FIG. 5, the circumferentially restricting portion 323 extends in the radial direction in a cross section along the radial direction from between the plane portions 231 a adjacent in the circumferential direction to the radially outer side, and the radially inner side has a short side. The cross section is formed in a substantially trapezoidal shape. The circumferential direction restricting portion 323 is formed such that an inner wall surface 323a that is a surface facing a locking portion 322 adjacent in the circumferential direction is in contact with the magnet side surface 31a of the permanent magnet 31 in the circumferential direction.

  As shown in FIG. 5, the radial restricting portion 324 has a predetermined length from the radially outer end of the circumferential restricting portion 323 toward the locking portion 322 adjacent in the circumferential direction in a cross section along the radial direction. It is extended.

  Further, in the cross section along the radial direction of the radial direction restricting portion 324, an inner facing surface 324a that is a surface facing the permanent magnet 31 on the radial inner side becomes a surface along the magnet arc surface 31c of the permanent magnet 31. It is formed in an arc shape with a radius r.

  In other words, since the outer peripheral surface 322a of the engaging portion 322 facing the stator 4 is formed with the same diameter as the virtual circle VC, the radial restriction portion 324 has a cross-sectional shape along the radial direction from the inner wall surface 323a to the tip. It is formed in the cross-sectional shape which tapers gradually.

Note that the boundary portion between the inner facing surface 324a of the radial direction restricting portion 324 and the inner wall surface 323a of the circumferential direction restricting portion 323 is, as shown in FIGS. 3 and 5, in the permanent magnet 31 in a cross section along the radial direction. A chamfered portion 322b chamfered with a radius smaller than the radius of the chamfered portion 31d is formed.
The locking portion 322 having such a configuration is configured by a locking portion 322 adjacent in the circumferential direction and a flat portion 321a of the core base portion 321 as a magnet mounting portion to which one permanent magnet 31 is fitted and mounted. Yes.

In the rotating electrical machine 1, the rotor 3 having the above-described configuration is formed such that the air gap between the stator 4 and the rotor 3 has a small air gap and a large air gap in the circumferential direction.
More specifically, as shown in FIG. 3, the air gap of the rotating electrical machine 1 is the smallest at the locking portion 322 of the rotor core 32 and the top of the permanent magnet 31 in the cross section along the radial direction.

Furthermore, as shown in FIG. 3, the air gap of the rotating electrical machine 1 gradually increases from the top of the permanent magnet 31 to the end in the circumferential direction, and becomes the largest at the end in the circumferential direction of the permanent magnet 31.
Thus, the rotary electric machine 1 is configured such that the size of the air gap varies depending on the position in the circumferential direction.

Next, in the rotary electric machine 1 having the above-described configuration, the flow of air flowing in the air gap and the surface temperature of the permanent magnet 31 when the rotor 3 starts to rotate will be described in detail with reference to FIGS. .
6 shows an explanatory view for explaining the flow of air in the air gap in the comparative example, FIG. 7 shows an explanatory view for explaining the flow of air in the air gap in the present embodiment, and FIG. 8 shows the present embodiment. The explanatory view explaining the surface temperature of permanent magnet 31 in a form is shown, and Drawing 9 shows the explanatory view explaining the surface temperature of permanent magnet 31 from which the size of magnet circular arc surface 31c differs.

6 and 7, the inner peripheral surface of the stator 4 is indicated by a two-dot chain line for clarity of illustration.
8 and 9, for the sake of clarity, only the permanent magnet 31 among the components of the rotating electrical machine 1 is illustrated, and the air layer in the air gap is three-dimensionally and the rotor 3 It is shown in a transparent manner so that the outer peripheral surface becomes clear.

  First, as a comparative example, the flow of air flowing in an air gap, which is a gap between the stator 52 and the rotor 53, is simple in the rotating electric machine 50 in which the magnet arc surface 51a of the permanent magnet 51 is different from the above-described embodiment. Explained.

  As shown in FIG. 6, the magnet arc surface 51 a of the permanent magnet 51 in the comparative example is formed to have the same diameter as the outer radius of the rotor core 54, that is, the radius R of the virtual circle. The permanent magnet 51 is attached to the rotor core 54 so that the top of the magnet arc surface 51a is positioned on the virtual circle. For this reason, the air gap in the rotating electrical machine 50 has a uniform size as shown in FIG.

  In the case of such a rotating electric machine 50, when the rotor 53 starts to rotate in the rotational direction D that is clockwise as viewed in the axial direction, the air in the air gap is rotated in the rotational direction D by the shearing force of the rotor 53 as shown in FIG. Begins to flow toward. Since the air gap in the rotating electrical machine 50 is a uniform size, the air in the air gap becomes a flow F having a uniform flow velocity.

On the other hand, in the case of the rotating electrical machine 1 in the present embodiment, when the rotor 3 starts to rotate in the rotation direction D, as shown in FIG. 7, a virtual circle along the outer peripheral surface 322a of the locking portion 322 in the rotor core 32 ( In the gap between the stator 4 and the stator 4, an air flow F1 having a uniform flow velocity is generated.
On the other hand, in the gap between the virtual circle and the magnet arc surface 31 c of the permanent magnet 31, a vortex flow F <b> 2 that is relatively slower than the air flow F <b> 1 between the virtual circle and the stator 4 is generated.

  More specifically, after flowing in a space between the virtual circle and the magnet arc surface 31c of the permanent magnet 31 so as to spiral along the surface of the magnet arc surface 31c of the permanent magnet 31, as shown in FIG. A vortex F2 that joins the air flow F1 flowing between the virtual circle and the stator 4 is generated.

  Thus, when the rotor 3 starts to rotate, an air flow F1 and a vortex flow F2 having different flow directions and flow speeds are generated in the air gap of the rotating electrical machine 1. Then, in the gap between the stator 4 and the top of the permanent magnet 31, the air in which the vortex F <b> 2 joins the air flow F <b> 1 flowing between the virtual circle and the stator 4 flows.

  At this time, when the surface temperature of the magnet arc surface 31c of the permanent magnet 31 is viewed, as shown in FIG. 8, the black portion indicating the low temperature region is near the end in the circumferential direction of the magnet arc surface 31c and the magnet arc surface. It can be confirmed that this occurs near the top of 31c. That is, it can be confirmed that the vicinity of the top of the permanent magnet 31, which is likely to be hotter than other portions due to eddy current, is air-cooled by the air flowing through the top of the permanent magnet 31.

  Further, for example, when the magnet arc surface 31c of the permanent magnet 31 is formed with a radius r closer to the radius R of the virtual circle VC, as shown in FIG. 9, it is lower in the vicinity of the top of the magnet arc surface 31c than in FIG. Although the black part which shows a temperature range reduces, it can confirm that the top part vicinity of the permanent magnet 31 is air-cooled with the air which flows through the top part of the permanent magnet 31. FIG.

  For this reason, even when the magnet arc surface 31c of the permanent magnet 31 is formed with a radius r closer to the radius R of the virtual circle VC, a constant air cooling effect is obtained by the flow of air flowing through the top of the permanent magnet 31. It was confirmed that

  In other words, as the radius r of the magnet arc surface 31c in the permanent magnet 31 is closer to the radius R of the virtual circle VC, the air-cooling effect due to the flow of air flowing through the top of the permanent magnet 31 is reduced, and as shown in FIG. If the radius r of the magnet arc surface 31c in the magnet 31 substantially matches the radius R of the virtual circle VC, it can be said that it is difficult to obtain an air cooling effect due to the flow of air flowing through the top of the permanent magnet 31.

The rotating electrical machine 1 that realizes the air flow as described above can suppress a decrease in the magnetic force of the permanent magnet 31 due to the eddy current.
Specifically, since the top of the permanent magnet 31 is substantially coincided with the virtual circle VC along the outer circumferential surface of the rotor 3, that is, the virtual circle VC along the outer circumferential surface 322a of the locking portion 322 in the rotor core 32, An air gap, which is a gap between the stator 4 and the rotor 3, is minimized at the locking portion 322 of the rotor core 32 and the top of the permanent magnet 31.

  Furthermore, since the magnet arc surface 31c of the permanent magnet 31 is formed with a radius r smaller than the radius R of the virtual circle VC, the gap between the stator 4 and the permanent magnet 31 is circumferential from the top of the permanent magnet 31. Gradually increases toward the end of the permanent magnet 31 and becomes the maximum at the end of the permanent magnet 31 in the circumferential direction.

For this reason, in the rotating electrical machine 1, portions where the air gap is minimum and portions where the air gap is larger than the portion where the air gap is minimum are alternately formed in the circumferential direction.
In the rotating electrical machine 1 having such an air gap, when the rotor 3 starts to rotate, the air in the air gap starts to flow due to the shearing force generated by the rotation of the rotor 3.

  At this time, in the air gap, between the virtual circle VC and the stator 4, the air flow F <b> 1 flowing in the rotation direction of the rotor 3, the virtual circle VC, the magnet arc surface 31 c of the permanent magnet 31, and the rotor core 32. In the range surrounded by the locking portion 322, a vortex flow F2 that flows in a spiral manner is generated.

  Therefore, the air flow F1 between the virtual circle VC and the stator 4 is a vortex flow F2 that flows in a range surrounded by the virtual circle VC, the magnet arc surface 31c of the permanent magnet 31, and the engaging portion 322 of the rotor core 32. The flow rate is relatively faster than the flow velocity.

  Furthermore, since the air in the range surrounded by the virtual circle VC, the magnet arc surface 31c of the permanent magnet 31 and the engaging portion 322 of the rotor core 32 is in contact with the vicinity of the end of the permanent magnet 31 in the circumferential direction, the temperature is high. It is hard to become. For this reason, the rotary electric machine 1 can merge the relatively low-temperature vortex F2 with the air flow F1 flowing between the virtual circle VC and the stator 4.

  As a result, the rotating electrical machine 1 increases the flow of air flowing through the gap between the top of the permanent magnet 31 and the stator 4 and lowers the temperature thereof, compared to a rotating electrical machine having a uniform air gap. Can do.

For this reason, the rotary electric machine 1 can efficiently air-cool the vicinity of the top of the magnet arc surface 31c in the permanent magnet 31, and can suppress the temperature in the vicinity of the top of the permanent magnet 31 from rising due to eddy current.
Therefore, the rotating electrical machine 1 can suppress a decrease in the magnetic force of the permanent magnet 31 due to the eddy current.

  Further, the locking portion 322 of the rotor core 32 extends from the outer end in the radial direction in the circumferential direction, and the radial restricting portion abuts in the radial direction with the vicinity of the end of the magnet arc surface 31c in the circumferential direction. By providing 324, the rotating electrical machine 1 can reliably hold the permanent magnet 31 with a part of the arcuate surface 31c of the magnet exposed in the air gap by the rotor core 32.

Thereby, when the rotor 3 starts to rotate, the rotating electrical machine 1 can restrict the movement of the permanent magnet 31 to the outside in the radial direction due to the centrifugal force, and can secure a stable air gap.
For this reason, the rotating electrical machine 1 can flow air with a stable flow rate in the gap between the top of the permanent magnet 31 and the stator 4.
Therefore, the rotating electrical machine 1 can reliably hold the permanent magnet 31 disposed close to the stator 4 and can suppress a decrease in the magnetic force of the permanent magnet 31.

In correspondence between the configuration of the present invention and the above-described embodiment,
The facing surface of the present invention corresponds to the magnet arc surface 31c of the embodiment,
Similarly,
The radius of the virtual circle corresponds to the radius R of the virtual circle VC,
A radius smaller than the radius of the virtual circle corresponds to a radius r smaller than the radius R of the virtual circle VC,
The radially inner surface of the permanent magnet corresponds to the magnet plane 31b of the permanent magnet 31,
The contact surface corresponds to the planar portion 321a of the core base 321,
The front end surface corresponds to the outer peripheral surface 322a of the locking portion 322,
The protruding portion corresponds to the locking portion 322,
The contact portion corresponds to the radial direction restriction portion 324 of the locking portion 322,
The present invention is not limited only to the configuration of the above-described embodiment, and many embodiments can be obtained.

For example, the rotary electric machine 1 has 16 poles and 24 slots. However, the present invention is not limited to this, and the number of poles and the number of slots may be appropriate numbers according to the size of the rotary electric machine and a desired shaft torque.
Moreover, although it was set as the permanent magnet 31 fitted and attached to the magnet mounting part comprised by the core base part 321 and the latching | locking part 322, it is not limited to this, When laminating | stacking the thin plate material made from an electromagnetic steel plate, a thin plate material In consideration of misalignment between them, a permanent magnet having a slightly smaller outer shape than the magnet mounting portion may be used.

  INDUSTRIAL APPLICABILITY The present invention can be applied to a drive motor in various apparatuses and automobiles, a generator that outputs electric power, or a rotating electric machine used as a motor / generator, and more preferably to a rotating electric machine in which high output is desired. can do.

DESCRIPTION OF SYMBOLS 1 ... Rotary electric machine 2 ... Rotating shaft 3 ... Rotor 4 ... Stator 31 ... Permanent magnet 31b ... Magnet plane 31c ... Magnet circular surface 32 ... Rotor core 321a ... Plane part 322 ... Locking part 322a ... Outer peripheral surface 324 ... Radial direction control part R ... radius r ... radius VC ... virtual circle

Claims (2)

A radial gap type rotating electrical machine that is provided integrally with a rotating shaft and includes a rotor having a substantially circular outer peripheral shape when viewed from the axial direction of the rotating shaft, and a stator that is supported so as not to rotate. Because
The rotor is
A plurality of permanent magnets having opposing surfaces facing the stator;
A rotor core that holds the plurality of permanent magnets disposed along the circumferential direction of the rotor;
The facing surface of the permanent magnet is
In the cross section along the radial direction of the rotor, it is formed in a cross-section arc shape with a radius smaller than the radius of the virtual circle along the outer peripheral surface of the rotor,
The rotor core is
An abutting surface that abuts on a radially inner surface of the permanent magnet disposed on the imaginary circle with the tops of the opposing surfaces substantially coincided with each other;
A rotating electrical machine including a plurality of projecting portions that project outwardly in the radial direction from between the contact surfaces adjacent to each other in the circumferential direction and whose tip surfaces form the outer circumferential surface of the rotor core. The protrusion of the rotor core is
2. The apparatus according to claim 1, further comprising an abutting portion that extends from the outer end portion in the radial direction toward the circumferential direction, and abuts near the end portion of the facing surface in the circumferential direction and in the radial direction. Rotating electric machine.

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