JP2009194985A - Rotating electrical machine - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To obtain a rotating electrical machine to stably hold a permanent magnet on a yoke portion side and reduce the leakage of magnetic flux generated by the permanent magnet. <P>SOLUTION: Magnet holders 30, 35 are fit and held in holding grooves 40, 41 formed in the opposite portions on the outer diameter side of the inner wall faces of valley portions 25, 26 and thus installed over the valley portions 25, 26. Permanent magnets 32, 37 are fit in fitting grooves formed in the magnet holders 30, 35 and held by the magnet holders 30, 35 so that the center of each of the permanent magnets 32, 37 is shifted from the axial center of the corresponding magnet holder 30, 35 toward a field coil 14. When seen from the outside in the radial direction, the permanent magnets 32, 37 are partially exposed from claw-like magnetic pole portions 20, 24 and the remaining parts are positioned at the inner radius portions of the claw-like magnetic pole portions 20, 24. The permanent magnets are magnetized and oriented so that extended lines passing through their centers in the direction 42 of magnetization are directed toward the inner circumferential surfaces of the tip parts of the claw-like magnetic pole portions 20, 24. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a rotating electrical machine such as a vehicular AC generator, and more particularly to a permanent magnet holding structure in a Landel rotor.

  Vehicle alternators using Landel rotors have been used in automobiles for decades. Due to environmental problems in recent years, the load of electrical components mounted on the vehicle has increased rapidly, and a further increase in the power generation amount of the Landel rotor has been demanded.

  Conventionally, in order to solve such a problem, a means for arranging a permanent magnet between claw-shaped magnetic pole portions facing in the circumferential direction of a Landel-type rotor has been taken (for example, see Patent Document 1).

US Pat. No. 4,959,577

  In conventional rotating electrical machines, since the permanent magnet is held between adjacent claw-shaped magnetic pole portions, relative displacement occurs between adjacent claw-shaped magnetic pole portions during high-speed rotation, and the permanent magnet cannot be stably held. There was a problem.

  In a Landel type rotor core, a core body with a claw-shaped magnetic pole part extending radially outward from the yoke is molded by cold forging, and then radially outward from the yoke. A claw-shaped magnetic pole portion is formed by bending a portion corresponding to the claw-shaped magnetic pole portion extending in a substantially right angle. And it is necessary to increase the yield in the step of bending the claw-shaped magnetic pole part, and it is a common practice to simultaneously form valleys in the part located between adjacent claw-shaped magnetic pole parts of the yoke part when molding the core body. It is.

  Here, it is conceivable to eliminate the influence of the displacement of the claw-shaped magnetic pole part during high-speed rotation on the magnet holding structure by holding the permanent magnet on the yoke part side. And when making a permanent magnet hold | maintain at the yoke part side of the rotor core which has a trough part in the site | part located between adjacent claw-shaped magnetic pole parts of a yoke part, a permanent magnet is attached so that a trough part may be embedded. In this case, since the weight of the permanent magnet becomes excessively large and an excessive centrifugal force acts on the permanent magnet, the permanent magnet cannot be stably held. It is also possible to hold a permanent magnet on a magnet holding member made of a magnetic material attached so as to bury the valley. In this case, the weight of the magnet holding member becomes excessively large, and an excessive centrifugal force acts on the magnet holding member, so that the magnet holding member cannot be stably held and the permanent magnet can be stably held. Disappear.

  Further, when the permanent magnet is held on the yoke part side, the permanent magnet is magnetically arranged so that the magnetic flux generated by the permanent magnet flows through a closed magnetic circuit in the rotor. It is necessary to reduce the leakage magnetic flux that flows through the stator core.

  The present invention has been made to solve such a problem, and provides a rotating electrical machine that can stably hold a permanent magnet on the yoke portion side and can reduce leakage of magnetic flux generated by the permanent magnet. For the purpose.

  The rotating electrical machine according to the present invention includes a boss portion, a pair of yoke portions extending radially outward from both axial end edges of the boss portion, and an axial direction alternately from each of the pair of yoke portions. Each of the yoke portions between the claw-shaped magnetic pole portions that have a plurality of claw-shaped magnetic pole portions that extend and mesh with each other and are arranged in the circumferential direction, and a trough that curves toward the inner diameter side is adjacent in the circumferential direction. In a space surrounded by a pole core fixed to a rotating shaft inserted through the axial center position of the boss portion, the boss portion, the pair of yoke portions, and the plurality of claw-shaped magnetic pole portions. A rotor having a housed field coil; and a stator disposed so as to surround an outer periphery of the rotor via a predetermined air gap. The claw-shaped magnetic pole part is manufactured so that the tip side thereof overlaps with the yoke part in the axial direction, and the holding groove is on the base side of the claw-shaped magnetic pole part of the pole core, and the outer diameter of the inner wall surface of the trough part A magnet holder made of a magnetic material is opened to each of the opposing parts on the side and recessed from the axially outer side of the yoke portion toward the field coil side with the groove direction as an axial direction. Fitted into and held in the holding groove and spanned in the trough, and the fitting groove opens in a direction positioned on the outer diameter side of the magnet holder fitted and held in the holding groove, and The groove holder is recessed in the magnet holder in the axial direction, and the permanent magnet is made to have a shorter axial length than the magnet holder, and is fitted into the fitting groove, and the center of the permanent magnet is The magnet holder is shifted from the axial center of the magnet holder to the field coil side. It is held. When viewed from the outside in the radial direction, the permanent magnet has a part of the permanent magnet exposed from the claw-shaped magnetic pole part, and the remaining part is located at the inner diameter part of the claw-shaped magnetic pole part, and further its center Is extended so that the extension line extending in the direction of magnetization passes toward the inner peripheral surface on the tip end side of the claw-shaped magnetic pole portion.

According to this invention, since the magnet holder is installed in the trough, it is not necessary to fill the trough with the magnet holder, and the volume of the magnet holder can be reduced. Therefore, during high-speed rotation, the centrifugal force acting on the magnet holder is reduced, and the magnet holder can be stably held on the pole core with a simple holding structure without being affected by the displacement of the claw-shaped magnetic pole portion. Further, since the permanent magnet is held by the magnet holder erected in the valley, the permanent magnet can be made to the minimum necessary size. Therefore, the centrifugal force acting on the permanent magnet is reduced, and the permanent magnet can be stably held on the magnet holder with a simple holding structure without being affected by the displacement of the claw-shaped magnetic pole portion.
In addition, the permanent magnet is held by the magnet holder with its center shifted from the axial center of the magnet holder to the field coil side, so that it faces the tip side inner peripheral surface of the claw-shaped magnetic pole part of the permanent magnet. Thus, the magnetic flux leakage generated by the permanent magnet can be reduced.
Further, the permanent magnet is magnetized and oriented so that the extension line in the magnetization direction passing through the center thereof is directed to the inner peripheral surface on the tip side of the claw-shaped magnetic pole portion, so that the leakage of magnetic flux generated by the permanent magnet is further reduced. Can be reduced. Thereby, the exposed part from the claw-shaped magnetic pole part can be increased, the amount of magnets can be increased, and the output can be increased.

Embodiment 1 FIG.
FIG. 1 is a sectional view schematically showing an automotive alternator according to Embodiment 1 of the present invention, and FIG. 2 shows a rotor applied to the automotive alternator according to Embodiment 1 of the present invention. FIG. 3 is a perspective view, FIG. 3 is a perspective view for explaining a method of mounting a permanent magnet on a magnet holder in the automotive alternator according to Embodiment 1 of the present invention, and FIGS. 4 and 5 are embodiments of the present invention. 1 is a cross-sectional view showing a main part of a rotor applied to an automotive alternator according to No. 1;

  1 to 5, the vehicle alternator 1 supports a case 4 formed of a substantially bowl-shaped aluminum front bracket 2 and a rear bracket 3, and a rotating shaft 16 supported by the case 4 via a bearing 5. The rotor 13 rotatably disposed in the case 4, the pulley 6 fixed to the end of the rotating shaft 16 extending to the front side of the case 4, and the axial direction of the rotor 13 (hereinafter referred to as the rotor 13). And the stator 10 having a fixed air gap 29 with respect to the rotor 13 and surrounding the outer periphery of the rotor 13 and fixed to the case 4. A pair of slip rings 8 fixed to the rear side of the rotary shaft 16 and supplying current to the rotor 13; and a pair of brushes 9 disposed in the case 4 so as to slide on the slip rings 8; It is equipped with. Although not shown, a rectifier that rectifies alternating current generated in the stator 10 into direct current, a voltage regulator that adjusts the magnitude of the alternating voltage generated in the stator 10, and the like are disposed in the case 4. .

  The stator 10 is wound around a cylindrical stator core 11 and the stator core 11, and an alternating current is generated by a change in magnetic flux from a field coil 14 (to be described later) as the rotor 13 rotates. And.

The rotor 13 includes a field coil 14 that generates a magnetic flux when an excitation current is passed, a pole core 15 that is provided so as to cover the field coil 14, and a magnetic pole is formed by the magnetic flux, and an axial center position of the pole core 15. And a rotating shaft 16 penetrating the shaft.
The pole core 15 is divided into first and second pole core bodies 17 and 21 made of a low carbon steel such as S10C by a cold forging method.

  The first pole core body 17 has a cylindrical outer peripheral surface, a first boss portion 18 formed with a rotation shaft insertion hole 18a penetrating the axial center position, and a radially outer side from one end edge of the first boss portion 18. A thick ring-shaped first yoke portion 19 extended to the first yoke portion 19 and a first claw-shaped magnetic pole portion 20 extended from the outer peripheral portion of the first yoke portion 19 to the other axial end side. Yes. The first claw-shaped magnetic pole portion 20 has a substantially trapezoidal outermost surface shape, the circumferential width gradually decreases toward the distal end side, and the radial thickness gradually decreases toward the distal end side. It is formed in a tapered shape, and eight, for example, are arranged on the outer peripheral portion of the first yoke portion 19 at an equiangular pitch in the circumferential direction. Further, the first trough portion 25 is recessed in a U-shape that is curved in a convex shape toward the inner diameter side at a position located between the adjacent first claw-shaped magnetic pole portions 20 of the first yoke portion 19. Yes. Furthermore, the first fold line 27 formed when the first claw-shaped magnetic pole part 20 is bent is formed so as to extend in the radial direction at the boundary between the first yoke part 19 and the first claw-shaped magnetic pole part 20. Has been.

  The second pole core body 21 has a cylindrical outer peripheral surface, a second boss portion 22 formed with a rotation shaft insertion hole 22a penetrating the axial center position, and a radial direction from the other end edge of the second boss portion 22. A thick ring-shaped second yoke portion 23 extending outward, and a second claw-shaped magnetic pole portion 24 extending from the outer periphery of the second yoke portion 23 to one end in the axial direction. Yes. The second claw-shaped magnetic pole portion 24 has a substantially trapezoidal outermost surface shape, its circumferential width gradually decreases toward the distal end side, and its radial thickness gradually decreases toward the distal end side. For example, eight taper shapes are arranged on the outer peripheral portion of the second yoke portion 23 at an equiangular pitch in the circumferential direction. Further, the second valley portion 26 is recessed in a U-shape that is convexly curved toward the inner diameter side at a portion located between the adjacent first claw-shaped magnetic pole portions 24 of the second yoke portion 23. Yes. Furthermore, the second fold line 28 formed when the second claw-shaped magnetic pole portion 24 is bent is formed so as to extend in the radial direction at the boundary between the second yoke portion 23 and the second claw-shaped magnetic pole portion 24. Has been.

  The first and second pole core bodies 17 and 21 configured as described above mesh with the first and second claw-shaped magnetic pole portions 20 and 24 alternately, and the other end surface of the first boss portion 18 is connected to the second boss. It abuts on one end surface of the portion 22 and is fixed to the rotary shaft 16 inserted through the rotary shaft insertion holes 18a, 22a. A field coil 14 wound around a bobbin (not shown) includes first and second boss portions 18 and 22, first and second yoke portions 19 and 23, and first and second claw-shaped magnetic poles. It is mounted in a space surrounded by the parts 20 and 24. Here, the first and second boss portions 18 and 22 and the first and second yoke portions 19 and 23 correspond to the boss portion of the pole core 15 and the pair of yoke portions, respectively. Further, in the axial direction, the distal end sides of the first and second claw-shaped magnetic pole portions 20 and 24 overlap the second and first yoke portions 23 and 19, respectively.

  The 1st magnet holder 30 is produced by the cross-sectional trapezoid which has predetermined thickness using magnetic materials, such as iron and an iron-type magnetic alloy. And the 1st fitting groove | channel 31 which makes a groove direction the thickness direction of the 1st magnet holder 30 is recessedly provided so that it may open in the upper surface of the 1st magnet holder 30. FIG. Here, the upper and lower surfaces of the first magnet holder 30 and the bottom surface of the first fitting groove 31 are flat surfaces parallel to each other. The first fitting groove 31 is formed in a wedge shape whose groove width gradually decreases toward the opening. The first permanent magnet 32 is manufactured to have an outer shape conforming to the inner shape of the first fitting groove 31, that is, a cross section in a plane orthogonal to the thickness direction, and a thickness smaller than that of the first magnet holder 30. The upper and lower surfaces are flat surfaces parallel to each other. And the 1st permanent magnet 32 makes the thickness direction correspond to the thickness direction of the 1st magnet holder 30, and makes the one end surface of the 1st permanent magnet 32, and the one end surface of the 1st magnet holder 30 the same surface position. These are fitted in the first fitting grooves 31, are coated with an adhesive as necessary, and are held by the first magnet holder 30. Then, the bottom surface of the first fitting groove 31 and the lower surface of the first permanent magnet 32 are in close contact with each other with a minute gap, and the first magnet holder 30 and the first permanent magnet 32 are magnetically connected. Has been.

  The second magnet holder 35 is made in the same shape using the same material as the first magnet holder 30. The second permanent magnet 37 is made in the same shape using the same material as the first permanent magnet 32. The second permanent magnet 37 has a thickness direction coinciding with the thickness direction of the second magnet holder 35, and one end face of the second permanent magnet 37 and one end face of the second magnet holder 35 are positioned on the same plane. 2 is fitted in the fitting groove 36, and an adhesive is applied as necessary, and is held by the second magnet holder 35. The bottom surface of the second fitting groove 36 and the bottom surface of the second permanent magnet 37 are in close contact with each other with a minute gap, and the second magnet holder 35 and the second permanent magnet 37 are magnetically connected. Has been.

  The first holding groove 40 opens to each of the opposing portions on the outer diameter side of the inner wall surface of each first trough portion 25 on the root side of each first claw-shaped magnetic pole portion 20 of the first pole core body 17; and The first yoke portion 19 is recessed so as to reach the first fold line 27 from one end of the first yoke portion 19 toward the other end side with the groove direction as the axial direction. Similarly, the second holding groove 41 is opened at each of the opposing portions on the outer diameter side of the inner wall surface of each second valley portion 26 on the root side of each second claw-shaped magnetic pole portion 24 of the second pole core body 21. And it is recessed so that it may reach | attain the 2nd bending line 28 toward the one end side from the other end of the 2nd yoke part 23 by making a groove direction into an axial direction. Here, the first and second holding grooves 40 and 41 are formed in a groove shape in which both side portions of the first and second magnet holders 30 and 35 are fitted by broaching or end milling.

  The first magnet holder 30 is press-fitted into the first holding groove 40 facing from the outside in the axial direction with the first permanent magnet 32 facing upward, and an adhesive is applied as necessary, and each first trough portion is applied. It is magnetically connected to the first pole core body 17 in a state where it is installed on the first pole core body 17. At this time, the thickness directions of the first magnet holder 30 and the first permanent magnet 32 coincide with the axial direction. Further, the first fitting groove 31 opens in a direction positioned on the outer diameter side of the first magnet holder 30 that is fitted and held in the first holding groove 40.

  The first permanent magnet 32 is shifted to the field coil 14 side with respect to the center in the thickness direction of the first magnet holder 30, that is, offset to the field coil 14 side in the axial direction. It is held by the holder 30. With respect to the axial direction, the field coil 14 side of the first permanent magnet 32 overlaps with the second claw-shaped magnetic pole portion 24, and the opposite side of the field coil 14 of the first permanent magnet 32 overlaps with the second claw-shaped magnetic pole portion 24. Absent. That is, when viewed from the outside in the radial direction, a part of the first permanent magnet 32 is exposed from the second claw-shaped magnetic pole part 24, the remaining part is located at the inner diameter part of the second claw-shaped magnetic pole part 24, and the upper surface thereof is the first. It faces the inner peripheral surface of the tip end side of the two-claw-shaped magnetic pole part 24 with a predetermined gap. Further, the bottom surface of the first fitting groove 31 and the lower surface of the first permanent magnet 32 are flat surfaces in contact with the cylindrical surface coaxial with the rotor 13. The cross section of the first permanent magnet 32 in a plane including the axis of the rotor 13 is rectangular. The center of the permanent magnet is a portion that is the center between the upper surface and the lower surface of the permanent magnet and the center in the thickness direction.

  The second magnet holder 35 is press-fitted into the second holding groove 41 facing from the outside in the axial direction with the second permanent magnet 37 facing upward, and an adhesive is applied as necessary, and each second valley portion 26 is applied. The second pole core body 21 is attached to the second pole core body 21 while being magnetically connected in a state of being erected on the upper side. At this time, the thickness directions of the second magnet holder 35 and the second permanent magnet 37 coincide with the axial direction. Further, the second fitting groove 36 opens in a direction positioned on the outer diameter side of the second magnet holder 35 that is fitted and held in the second holding groove 41.

  The second permanent magnet 37 has its center shifted to the field coil 14 side with respect to the center in the thickness direction of the second magnet holder 35, that is, offset to the field coil 14 side in the axial direction. It is held by the holder 35. With respect to the axial direction, the field coil 14 side of the second permanent magnet 37 overlaps the first claw-shaped magnetic pole part 20, and the opposite side of the field coil 14 of the second permanent magnet 37 overlaps the first claw-shaped magnetic pole part 20. Absent. That is, when viewed from the outside in the radial direction, a part of the second permanent magnet 37 is exposed from the first claw-shaped magnetic pole part 20, the remaining part is located at the inner diameter part of the first claw-shaped magnetic pole part 20, and the upper surface thereof is the first. The one claw-shaped magnetic pole part 20 faces the inner peripheral surface on the front end side with a predetermined gap. The bottom surface of the second fitting groove 36 and the bottom surface of the second permanent magnet 37 are flat surfaces that are in contact with the cylindrical surface coaxial with the rotor 13. The cross section of the second permanent magnet 37 in a plane including the axis of the rotor 13 is rectangular.

  Further, the first permanent magnet 32 includes the axis of the rotor 13 and passes through the center of the first permanent magnet 32 so that the magnetization direction 42 is inclined upward toward the field coil 14 side. It is magnetized and oriented so as to be inclined. An extension line in the magnetization direction 42 passing through the center of the first permanent magnet 32 is directed toward the inner peripheral surface on the distal end side of the second claw-shaped magnetic pole portion 24 that is opposed. Similarly, the second permanent magnet 37 includes the axis of the rotor 13 and passes through the center of the second permanent magnet 37, so that the magnetization direction 42 is an upward gradient toward the field coil 14 side. The magnets are oriented so as to be inclined. An extension line in the magnetization direction 42 passing through the center of the second permanent magnet 37 is directed toward the inner peripheral surface on the front end side of the first claw-shaped magnetic pole portion 20 facing each other. As shown in FIG. 1, when the field coil 14 is energized and the magnetic field 45 is generated in the direction of the arrow, the first and second permanent magnets 32 and 37 are magnetized in the opposite direction to the magnetic field 45. Is done. In the case of a design in which the direction of the magnetic field 45 generated by the field current flowing through the field coil 14 is reversed, the first and second permanent magnets 32 and 37 are also magnetized and oriented in opposite directions.

Next, the operation of the vehicular AC generator 1 configured as described above will be described.
First, a current is supplied from a battery (not shown) to the field coil 14 of the rotor 13 via the brush 9 and the slip ring 8, and a magnetic flux is generated. By this magnetic flux, the first claw-shaped magnetic pole part 20 of the first pole core body 17 is magnetized to the N pole, and the second claw-shaped magnetic pole part 24 of the second pole core body 21 is magnetized to the S pole.
On the other hand, the rotational torque of the engine is transmitted to the rotating shaft 16 via a belt (not shown) and the pulley 6 and the rotor 13 is rotated. Therefore, a rotating magnetic field is applied to the stator coil 12 of the stator 10, and an electromotive force is generated in the stator coil 12. This AC electromotive force is rectified into a DC current by a rectifier, and the battery is charged or supplied to an electric load.

Next, the operation of the magnetic flux will be described with reference to FIGS.
First, when the field coil 14 is energized, a magnetic flux 46 is generated. This magnetic flux 46 enters the teeth portion of the stator core 11 from the first claw-shaped magnetic pole portion 20 through the air gap 29. Then, the magnetic flux 46 moves in the circumferential direction from the tooth portion of the stator core 11 through the core back portion, and passes through the air gap 29 from the tooth portion facing the adjacent second claw-shaped magnetic pole portion 24 to the second. The claw-shaped magnetic pole part 24 is entered. Next, the magnetic flux 46 that has entered the second claw-shaped magnetic pole portion 24 passes through the second yoke portion 23, the second boss portion 22, the first boss portion 18, and the first yoke portion 19, and thus the first claw-shaped magnetic pole portion. 20 is reached. Here, in the conventional Landell type rotor, the first and second pole core bodies are designed to be limited, so that magnetic saturation occurs due to the magnetic field generated by the field coil, and the magnetic flux generated in the rotor decreases.

  In the first embodiment, the first and second permanent magnets 32 and 37 are magnetized and oriented so as to be opposite to the direction of the magnetic field 45 generated by the field coil 14. Therefore, the direction of the magnetic field generated by the first and second permanent magnets 32 and 37 is opposite to the magnetic field 45 generated by the field coil 14. In order for the magnetic flux 47 generated from the first and second permanent magnets 32 and 37 to interlink with the stator core 11, it is necessary to reciprocate through the air gap 29 having a large magnetic resistance. The first and second permanent magnets 32 and 37 are disposed on the inner diameter side of the second and first claw-shaped magnetic pole portions 24 and 20, and the first and second claw-shaped magnetic pole portions 20 and 24 It arrange | positions so that it may circulate with a shorter magnetic path length with respect to the surrounding surface side.

  In addition, a part of the first and second permanent magnets 32 and 37 is exposed from the second and first claw-shaped magnetic pole portions 24 and 20 when viewed from the outside in the radial direction. A part of the magnetic flux 47 generated from the magnetic flux 47 tends to flow from the exposed portion from the first claw-shaped magnetic pole portion 20 to the stator core 11. In the first embodiment, the extension line in the magnetization direction 42 passing through the center of the second permanent magnet 37 is directed toward the inner peripheral surface on the tip end side of the first claw-shaped magnetic pole portion 24 facing the first claw-shaped magnetic pole. Also in the exposed part from the part 20, the magnetic flux 47 flows toward the tip side inner peripheral surface of the first claw-shaped magnetic pole part 20, and the amount of magnetic flux flowing in the stator core 11 is reduced. Therefore, most of the magnetic flux 47 flows through the magnetic circuit closed inside the rotor 13 without detouring to the stator core 11.

That is, the magnetic flux 47 generated from the first permanent magnet 32 enters the first magnet holder 30. Here, below the 1st magnet holder 30, the 1st trough part 25, ie, a big space | gap exists. Therefore, the magnetic flux 47 that has entered the first magnet holder 30 flows in the first magnet holder 30 on both sides in the circumferential direction and enters the first yoke portion 19, and the first boss portion 18 and the second boss portion 22. Then, it passes through the second yoke portion 23 and the second claw-shaped magnetic pole portion 24, and returns to the first permanent magnet 37 through a gap. Further, the magnetic flux 47 generated from the second permanent magnet 37 enters the first claw-shaped magnetic pole part 20 through the air gap, passes through the first yoke part 19, the first boss part 18, and the second boss part 22, Enter the second yoke 23. The magnetic flux 47 that has entered the second yoke portion 23 flows radially outward on both sides of the second valley portion 26 of the second yoke portion 23, and the second magnet holder 35 from both ends of the second magnet holder 35. And returns to the second permanent magnet 37.
Therefore, the magnetic flux 47 generated by the first and second permanent magnets 32 and 37 is opposite to the magnetic flux 46 generated by the field coil 14, and the magnetic flux constituting the first and second pole core bodies 17 and 21. The density can be greatly reduced and magnetic saturation can be eliminated.

  Next, by using the vehicle alternator 1 configured as described above, the no-load stator linkage magnetic flux amount with respect to the field magnetomotive force (field ampere turn) and the power generation amount with respect to the rotational speed (DC current A). And the results are shown in FIGS. Further, for comparison, a conventional device in which the first and second permanent magnets 32 and 37 are omitted is manufactured, and the no-load stator linkage magnetic flux amount with respect to the field magnetomotive force and the power generation amount with respect to the rotational speed are measured. The results are shown in FIGS. 8 and 9, the solid line indicates the product of the present invention, and the dotted line indicates the conventional device.

  From FIG. 8, in the region where the field magnetomotive force is small, the difference between the vehicular AC generator 1 and the conventional device is small, and when the magnetic saturation starts, the difference between the vehicular AC generator 1 and the conventional device is You can see it grows. That is, it can be seen that the arrangement of the first and second permanent magnets 32 and 37 eliminates magnetic saturation and increases the amount of magnetic flux linked to the stator 10. Similarly, it can be seen from FIG. 9 that the vehicular AC generator 1 can obtain a larger amount of power generation than the conventional device, particularly in the low-speed rotation region.

  That is, in the conventional device, 30% or more of the magnetomotive force of the field is consumed by the magnetic circuit of the rotor due to magnetic saturation, and it is difficult to increase the amount of magnetic flux. On the other hand, in this Embodiment 1, since magnetic saturation is eliminated as described above, it is presumed that the magnetic flux interlinked with the stator 10 is increased and the amount of power generation is increased. In particular, it was confirmed that the amount of power generation in the low-speed idling region where magnetic saturation is remarkable can be greatly increased.

  In the first embodiment, since the first and second magnet holders 30 and 35 are installed on the first and second valley portions 25 and 26, the first and second magnet holders 30 and 35 are used. It is not necessary to fill the first and second valley portions 25 and 26, and the volume of the first and second magnet holders 30 and 35 can be reduced. Further, since the first and second permanent magnets 32 and 37 are held by the first and second magnet holders 30 and 35 installed on the first and second valley portions 25 and 26, The second permanent magnets 32 and 37 can be made as small as necessary. Therefore, during high-speed rotation, the centrifugal force acting on the first and second magnet holders 30 and 35 and the first and second permanent magnets 32 and 37 is reduced, and the first and second causes caused by the centrifugal force and thermal expansion are reduced. There is no influence of the displacement of the second claw-shaped magnetic pole portions 20 and 24. Thus, the first and second permanent magnets 32 and 37 can be stably held on the pole core 15 with a simple holding structure.

Further, since the first and second magnet holders 30 and 35 connect the inner wall surfaces on the outer diameter side of the first and second valley portions 25 and 26 in the circumferential direction, the occurrence of deformation of the pole core 15 is suppressed. it can.
In addition, since the first and second magnet holders 30 and 35 are manufactured as separate parts from the first and second pole core bodies 17 and 21, it is easy to ensure processing accuracy, and the first and second holding grooves 40, The fitting surface with 41 and the fitting surfaces with the first and second permanent magnets 32 and 37 can be produced with high accuracy. Therefore, a gap in the fitting portion between the first and second magnet holders 30, 35 and the first and second yoke parts 19, 23, and further, the first and second magnet holders 30, 35, The gap between the fitting portions with the second permanent magnets 32 and 37 can be reduced to a minimum, and the magnetic resistance at these fitting portions is reduced. Therefore, the amount of magnetic flux of the magnet is increased and the magnet can be used effectively. Can do.

  Further, since the first and second permanent magnets 32 and 37 are positioned radially inward with respect to the outermost peripheral surface of the rotor 13, the stator slot harmonics are the first and second claw-shaped magnetic pole portions. The first and second permanent magnets 32 and 37 remain on the outermost peripheral surface portions of 20 and 24 and do not act so as to be directly induction-heated. As a result, the first and second permanent magnets 32 and 37 are prevented from being heated and demagnetized.

  Further, the extension line in the magnetization direction 42 passing through the centers of the first and second permanent magnets 32 and 37 is directed toward the inner peripheral surfaces of the distal ends of the second and first claw-shaped magnetic pole portions 24 and 20 facing each other. Thereby, the magnetic circuit of the 1st and 2nd permanent magnets 32 and 37 turns into a magnetic circuit closed inside the rotor, and the magnetic flux component linked to the stator 10 is reduced. Therefore, generation of the induced voltage of the first and second permanent magnets 32 and 37 during no-load no-excitation is suppressed. Moreover, even if the exposure amount from the 2nd and 1st nail | claw-shaped magnetic pole parts 24 and 20 of the 1st and 2nd permanent magnets 32 and 37 increases seeing from radial direction outer side, it links with the stator 10. An increase in magnetic flux component can be suppressed. From these results, the magnet amounts of the first and second permanent magnets 32 and 37 can be increased.

Further, since the first and second permanent magnets 32 and 37 are held in the first and second magnet holders 30 and 35 while being offset in the axial direction, the second of the first and second permanent magnets 32 and 37 is held. And the site | part facing the front end side inner peripheral surface of the 1st nail | claw-shaped magnetic pole parts 24 and 20 can be enlarged. As a result, leakage of the magnetic flux 47 generated by the first and second permanent magnets 32 and 37 can be reduced.
Since the first and second magnet holders 30 and 35 are made thicker than the thicknesses of the first and second permanent magnets 32 and 37, the first and second magnet holders 30 and 35 and the first and second magnet holders 30 and 35 are formed. 2 The fitting area with the holding grooves 40 and 41 can be increased. As a result, the holding strength of the first and second magnet holders 30 and 35 by the first and second yoke portions 19 and 23 is increased, and the centrifugal force is increased between the first and second permanent magnets 32 and 37 and the first and second magnets 30 and 35. Even when acting on the second magnet holders 30 and 35, the first and second permanent magnets 32 and 37 can be stably held.

  Here, the first and second bent lines 27 and 28 are formed at the boundary between the first and second yoke portions 19 and 23 and the first and second claw-shaped magnetic pole portions 20 and 24. The circumferential widths of the first and second claw-shaped magnetic pole portions 20 and 24 are gradually reduced from the bending lines 27 and 28 toward the tip side. Therefore, when the first and second holding grooves 40, 41 are formed beyond the first and second bent lines 27, 28 from the outside in the axial direction, the first and second holding grooves 40, 41, The fitting area with the second magnet holders 30 and 35 becomes smaller as the bending lines 27 and 28 are exceeded. For this reason, it is preferable not to form the first and second holding grooves 40 and 41 beyond the first and second bent lines 27 and 28 from the outside in the axial direction. Alternatively, when the first and second holding grooves 40 and 41 are formed so as to penetrate in the axial direction, the first and second magnet holders 30 and 35 exceed the bending lines 27 and 28 and the field coil. The first and second holding grooves 40 and 41 are preferably fitted so as not to be positioned on the 14 side.

  As described above, the first and second magnet holders 30 and 35 include the intersection O between the first and second holding grooves 40 and 41 and the first and second folding lines 27 and 28, and the first and second joints. The first and second holding grooves 40 and 41 are preferably fitted and held so as to be located between the end portions of the iron portions 19 and 23 on the outer side in the axial direction.

Although the first and second permanent magnets 32 and 37 are formed in a trapezoidal cross section having a predetermined thickness, the first and second permanent magnets 32 and 37 are the first and second magnet holders 30 and 37, respectively. The cross-sectional shape is not particularly limited as long as it is fitted and held on 35. Similarly, the first and second magnet holders 30 and 35 are formed in a trapezoidal cross section having a predetermined thickness, but the first and second magnet holders 30 and 35 are the first and second holding grooves. If it fits and is hold | maintained at 40 and 41, about the cross-sectional shape, it will not specifically limit. In other words, the groove shapes of the fitting groove and the holding groove may be appropriately set according to the shapes of the fitting portions of the permanent magnet and the magnet holder.
In addition, the first and second permanent magnets 32 and 37 are assumed to have a rectangular cross section in a plane including the axis of the rotor 13, but the cross sectional shape may be set as appropriate.

Embodiment 2. FIG.
In the second embodiment, except that the fold line is formed at the boundary between the claw-shaped magnetic pole portion and the yoke portion so as to be inclined downward toward the field coil side, the above-described embodiment is performed. The configuration is the same as in the first mode. Since the first and second permanent magnets 32 and 37 are similarly held by the first and second pole core bodies 17 and 21, only the holding structure of the second permanent magnet 37 will be described here. Description of the holding structure of the first permanent magnet 32 is omitted.

FIG. 10 is a cross-sectional view showing a main part of a rotor applied to an automotive alternator according to Embodiment 2 of the present invention.
In FIG. 10, the second fold line 28a is formed at the boundary between the second claw-shaped magnetic pole portion 24 and the second yoke portion 23 so as to be inclined downward toward the field coil 14 side. The second holding groove 41 is open to each of the opposing portions on the outer diameter side of the inner wall surface of each second valley portion 26 on the root side of each second claw-shaped magnetic pole portion 24 of the second pole core body 21. And it is recessedly provided so that it may reach | attain the 2nd bending line 28a toward the one end side from the other end of the 2nd yoke part 23 by making a groove direction into an axial direction. The second magnet holder 35 is press-fitted into the second holding groove 41 facing from the outside in the axial direction with the second permanent magnet 37 facing upward, and an adhesive is applied as necessary, and each second valley portion 26 is applied. It is magnetically connected in a state of being erected on and attached to the second pole core body 21.

  Here, the thickness directions of the second magnet holder 35 and the second permanent magnet 37 coincide with the axial direction. The center of the second permanent magnet 37 is shifted to the field coil 14 side with respect to the center in the thickness direction of the second magnet holder 35, that is, offset to the field coil 14 side in the axial direction. It is held by the two magnet holder 35. With respect to the axial direction, the field coil 14 side of the second permanent magnet 37 overlaps the first claw-shaped magnetic pole part 20, and the opposite side of the field coil 14 of the second permanent magnet 37 overlaps the first claw-shaped magnetic pole part 20. Absent. That is, when viewed from the outside in the radial direction, a part of the second permanent magnet 37 is exposed from the first claw-shaped magnetic pole part 20, the remaining part is located at the inner diameter part of the first claw-shaped magnetic pole part 20, and the upper surface thereof is the first. The one claw-shaped magnetic pole part 20 faces the inner peripheral surface on the front end side with a predetermined gap.

  The second permanent magnet 37 includes the axis of the rotor 13 and passes through the center of the second permanent magnet 37 so that the magnetization direction 42 is inclined upward toward the field coil 14 side. It is magnetized and oriented so as to be inclined. An extension line in the magnetization direction 42 passing through the center of the second permanent magnet 37 is directed toward the inner peripheral surface on the front end side of the first claw-shaped magnetic pole portion 20 facing each other.

  Therefore, this second embodiment can provide the same effect as the first embodiment.

Here, when the second holding groove 41 is formed from the outside in the axial direction beyond the second bend line 28a, the fitting area between the second holding groove 41 and the second magnet holder 35 is the second bend line. It becomes smaller as it exceeds 28a. Therefore, it is preferable not to form the second holding groove 41 from the outside in the axial direction beyond the second fold line 28a. Alternatively, when the second holding groove 41 is formed so as to penetrate in the axial direction, the second holding is performed so that the second magnet holder 35 is not positioned on the field coil 14 side beyond the second bending line 28a. It is preferable to fit in the groove 41.
As described above, also in the second embodiment, the second magnet holder 35 includes the intersection O between the second holding groove 41 and the second fold line 28a, and the end face on the outer side in the axial direction of the second yoke portion 23. It is preferable to be fitted and held in the second holding groove 41 so as to be positioned between the two.

Embodiment 3 FIG.
The third embodiment is configured in the same manner as in the first embodiment except that a permanent magnet whose magnetization direction is orthogonal to the lower surface of the permanent magnet is used. Since the first and second permanent magnets 32 and 37 are similarly held by the first and second pole core bodies 17 and 21, only the holding structure of the second permanent magnet 37 will be described here. Description of the holding structure of the first permanent magnet 32 is omitted.

FIG. 11 is a cross-sectional view showing a main part of a rotor applied to an automotive alternator according to Embodiment 3 of the present invention.
In FIG. 11, the second magnet holder 35A is made into a trapezoidal cross section having a predetermined thickness using a magnetic material such as iron or an iron-based magnetic alloy. And the 2nd fitting groove 36A which makes the groove direction the thickness direction of 2nd magnet holder 35A is recessedly provided so that it may open in the upper surface of 35 A of 2nd magnet holders. Here, the upper and lower surfaces of the second magnet holder 35A are flat surfaces parallel to each other. Moreover, the bottom surface 36a of the area | region of the one end side of 2nd fitting groove 36A is formed in the inclined surface used as a downward slope toward the one end side of 2nd magnet holder 35A. The groove width of the second fitting groove 36A is formed in a wedge shape that gradually decreases toward the opening.

  The second permanent magnet 37 has the thickness direction aligned with the thickness direction of the second magnet holder 35A, and the one end edge of the bottom surface of the second permanent magnet 37 is the one end edge of the bottom surface 36a of the second fitting groove 36A. Are fitted in the second fitting groove 36A, applied with an adhesive if necessary, and held by the second magnet holder 35A. Then, the bottom surface 36a of the second fitting groove 36A and the lower surface of the second permanent magnet 37 are in close contact with each other with a minute gap, and the second magnet holder 35A and the second permanent magnet 37 are magnetically connected. It is connected. The magnetization direction 42 of the second permanent magnet 37 is perpendicular to the lower surface of the second permanent magnet 37.

  The second magnet holder 35 </ b> A is fitted into the second holding groove 41 with one end side facing the field coil 14. At this time, the bottom surface 36a of the second fitting groove 36A and the lower surface of the second permanent magnet 37 are flat surfaces in contact with the truncated conical surface coaxial with the rotor 13. This flat surface has a gradient inclined in the direction from the outer diameter outer side position to the inner diameter inner side with respect to the rotating shaft 16 with respect to the field coil 14 in the axial direction, that is, a downward gradient toward the field coil 14. It is an inclined surface. Since the magnetization direction 42 of the second permanent magnet 37 is perpendicular to the lower surface of the second permanent magnet 37, the first claw-shaped magnetic poles facing the extension line of the magnetization direction 42 passing through the center of the second permanent magnet 37. It faces the inner peripheral surface of the tip side of the portion 20. Further, one end edge portion of the upper surface of the second permanent magnet 37 coincides with the second fold line 28.

Therefore, this third embodiment can provide the same effects as the first embodiment.
According to the third embodiment, since the bottom surface 36a of the second fitting groove 36A is formed as a downwardly inclined surface toward the field coil 14, the magnetization direction 42 is the lower surface of the second permanent magnet 37. The extension line in the magnetizing direction 42 is directed to the inner peripheral surface on the tip side of the first claw-shaped magnetic pole portion 20 facing the first claw-shaped magnetic pole portion 20. Therefore, it is not necessary to incline the magnetization direction with respect to the lower surface of the second permanent magnet 37, and the second permanent magnet 37 can be easily magnetized. Moreover, the clearance gap between the 2nd permanent magnet 37 and the 1st nail | claw-shaped magnetic pole part 20 becomes narrow, the magnetic flux amount of the 2nd permanent magnet 37 increases, and an output increases.

Here, also in the third embodiment, the second magnet holder 35A includes the intersection O between the second holding groove 41 and the second fold line 28 and the axially outer end face of the second yoke portion 23. It is preferable to be fitted and held in the second holding groove 41 so as to be positioned therebetween. When the second magnet holder 35A is fitted in the second holding groove 41 so that one end thereof coincides with the intersection point O, the one end side of the second permanent magnet 37 exceeds the second bend line 28 and is first. Since it enters the inner diameter part of the claw-shaped magnetic pole part 20, the leakage amount of magnetic flux generated from the second permanent magnet 37 can be further reduced.
Moreover, although only the bottom face 36a of the area | region of the one end side of 2nd fitting groove 36A shall be made into an inclined surface, it is good also considering the bottom face of the whole fitting groove as an inclined surface.

  In each of the above embodiments, the vehicle alternator has been described. However, the present invention is not limited to the vehicle alternator, and is applied to rotating electric machines such as a vehicle motor and a vehicle generator motor. Produces the same effect.

  Further, in each of the above embodiments, the magnet holder is arranged in all the valleys, but the magnet holder may be arranged by selecting an arbitrary valley. In this case, it is desirable to arrange the magnet holder in a balanced manner in the circumferential direction. For example, a magnet holder is not provided in the first pole core body, but a magnet holder is provided in all valleys of the second pole core body, or each of the first and second pole core bodies has a circumferential direction. You may arrange | position a magnet holder to every other trough part. Such a configuration can reduce the number of parts and increase the output with an inexpensive configuration, although the output is slightly reduced as compared with the case where magnet holders are arranged in all the valleys.

1 is a cross-sectional view schematically showing an automotive alternator according to Embodiment 1 of the present invention. It is a perspective view which shows the rotor applied to the alternating current generator for vehicles which concerns on Embodiment 1 of this invention. It is a perspective view explaining the mounting method to the magnet holder of the permanent magnet in the alternating current generator for vehicles concerning Embodiment 1 of this invention. It is sectional drawing which shows the principal part of the rotor applied to the alternating current generator for vehicles which concerns on Embodiment 1 of this invention. It is sectional drawing which shows the principal part of the rotor applied to the alternating current generator for vehicles which concerns on Embodiment 1 of this invention. It is a schematic diagram for demonstrating the flow of the magnetic flux in the alternating current generator for vehicles which concerns on Embodiment 1 of this invention. It is a schematic diagram for demonstrating the flow of the magnetic flux in the alternating current generator for vehicles which concerns on Embodiment 1 of this invention. It is a figure showing the relationship between the field magnetomotive force and stator interlinkage magnetic flux amount in the alternating current generator for vehicles which concerns on Embodiment 1 of this invention. It is a figure which shows the electric power generation amount with respect to the rotation speed in the alternating current generator for vehicles which concerns on Embodiment 1 of this invention. It is sectional drawing which shows the principal part of the rotor applied to the alternating current generator for vehicles which concerns on Embodiment 2 of this invention. It is sectional drawing which shows the principal part of the rotor applied to the alternating current generator for vehicles which concerns on Embodiment 3 of this invention.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 10 Stator, 13 Rotor, 14 Field coil, 15 Pole core, 16 Rotating shaft, 17 1st pole core body, 18 1st boss | hub part, 19 1st yoke part, 20 1st claw-shaped magnetic pole part, 21 2nd Pole core body, 22 2nd boss part, 23 2nd yoke part, 24 2nd claw-shaped magnetic pole part, 25 1st valley part, 26 2nd valley part, 27 1st fold line, 28, 28a 2nd fold line Wire, 29 air gap, 30 first magnet holder, 31 first fitting groove, 32 first permanent magnet, 35, 35A second magnet holder, 36, 36A second fitting groove, 37 second permanent magnet, 42 Magnetization direction, 40 1st holding groove, 41 2nd holding groove.

Claims (3)

A boss portion, a pair of yoke portions extending radially outward from both end edges in the axial direction of the boss portion, and a pair of yoke portions alternately extending in the axial direction from each of the yoke portions, meshing with each other. A plurality of claw-shaped magnetic pole portions arranged in a direction, and a trough curved toward the inner diameter side is formed at each yoke portion between the claw-shaped magnetic pole portions adjacent in the circumferential direction, and the boss portion A pole core fixed to a rotary shaft inserted through the axial center position of the magnetic field coil, and a field coil housed in a space surrounded by the boss portion, the pair of yoke portions, and the plurality of claw-shaped magnetic pole portions; A rotor having
In a rotating electrical machine comprising: a stator disposed so as to surround an outer periphery of the rotor via a predetermined air gap;
The claw-shaped magnetic pole part is produced so that the tip side thereof overlaps the yoke part in the axial direction,
A holding groove opens on each of the opposed portions on the outer diameter side of the inner wall surface of the valley portion on the base side of the claw-shaped magnetic pole portion of the pole core, and the axis of the yoke portion with the groove direction as an axial direction. Recessed from the outside of the direction toward the field coil side,
A magnet holder made of a magnetic material is fitted and held in the holding grooves facing each other and is laid on the valley.
The fitting groove is open with respect to the direction positioned on the outer diameter side of the magnet holder fitted and held in the holding groove, and is recessed in the magnet holder with the groove direction as an axial direction.
A permanent magnet is produced with a shorter axial length than the magnet holder and is fitted in the fitting groove, and the center of the permanent magnet is shifted from the axial center of the magnet holder to the field coil side. Is held by the magnet holder,
The permanent magnet has a part of the permanent magnet exposed from the claw-shaped magnetic pole part and the remaining part located at the inner diameter part of the claw-shaped magnetic pole part as viewed from the outside in the radial direction, and further passes through the center thereof. A rotating electrical machine characterized by being magnetized and oriented so that an extension line in a magnetization direction is directed to a tip side inner peripheral surface of the claw-shaped magnetic pole portion.   At a position in the axial direction of the fitting groove, a groove having a gradient in which at least the field coil side region is inclined toward the field coil side in a direction from the outer diameter outer side position to the inner diameter inner side with respect to the rotation shaft. The rotating electrical machine according to claim 1, wherein the rotating magnet is formed in a shape, and the permanent magnet is fitted to a region of the fitting groove inclined at the gradient and is held by the magnet holder. In the pole core, a fold line is formed at the boundary between the claw-shaped magnetic pole part and the yoke part,
The magnet holder is fitted and held in the holding groove so as to be located between the intersection of the holding groove and the fold line and the axially outer end surface of the yoke portion. The rotating electrical machine according to claim 1, wherein the rotating electric machine is characterized.

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