JP2010041799A - Field coil type rotary electric machine - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a field coil type rotary electric machine having a Lundell type rotor core, capable of increasing a torque and reducing iron loss, torque ripple and magnetic vibration. <P>SOLUTION: From among magnetic pole surfaces 44 of claw pole parts 43A, 43B of the Lundell type rotor core, the axially front parts thereof are deviated and provided on one side in the circumferential direction with respect to the axially rear parts. As a result, the effect can be exerted. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a field coil type rotating electrical machine used for, for example, a vehicle AC generator, and more particularly to an improvement of a field coil type rotating electrical machine having a Landel type rotor core.

  A Landel rotor core of a vehicle alternator having a so-called claw pole structure is composed of a pair of pole cores that are axially adjacent to each other and fitted to a rotating shaft. Each pole core has a boss portion in which a field coil is wound and a field magnetic flux flows in the axial direction, and protrudes radially outward at a predetermined circumferential pitch from the axial outer end portion of the boss portion. It is comprised by the some nail | claw pole part extended in the coil surrounding direction. The stator core is made of laminated steel plates and has a large number of teeth arranged in the circumferential direction at a constant tooth pitch. The outer end surface in the radial direction of each claw pole part is formed smaller in diameter than the inner peripheral surface of the stator core formed by connecting the radial inner end surfaces of the teeth by a predetermined small gap (electromagnetic gap) in the radial direction. Make up surface.

  As a result, the field flux that enters the teeth from the pole pole surface of one pole core flows through the back yoke of the stator core by an electrical angle π in the circumferential direction, and then flows from the teeth to the pole pole surface of the other pole core. Then, it returns to the original position through the boss part.

Generally, the claw pole has a tapered shape from the axial base end side toward the axial front end side, whereby the claw pole magnetic pole surface has a substantially trapezoidal circumferentially developed shape. This is to improve the anti-centrifugal force performance of the claw pole and smooth the rate of change of the field magnetic flux interlinked with the stator coil. On the other hand, the taper rate from the axial base end side to the axial tip side of the claw pole, that is, the circumferential width reduction rate is reduced, and the circumferentially developed shape of the claw pole magnetic pole surface is made more square than before. This is proposed in Patent Document 1. Thereby, since the area of one nail pole magnetic pole surface can be increased, the output can be increased.
JP 2007-209198 A

  However, it is known that the conventional Landell type rotor core described above has torque ripple and vibration caused by a change in the circumferential direction of the magnetic resistance due to the teeth pitch of the stator core. The torque ripple and vibration caused by the tooth pitch become prominent by adopting the rectangular claw pole magnetic pole surface as in Patent Document 1 described above. In other words, although the output can be increased by making the claw pole magnetic pole surface square, the reduction of torque ripple and vibration has prevented its wide practical use.

  On the other hand, the trapezoidal claw pole magnetic pole surface described above is more advantageous than the rectangular claw pole magnetic pole face in terms of torque ripple and vibration, but the component of the field flux that flows in the axial direction in the stator core (axis Since the eddy current increases, there is a problem that the iron loss is large.

  In order to reduce torque ripple and vibration caused by teeth pitch, it is a well-known technique to skew the teeth of the stator, but the manufacturing process of the stator core is complicated and the length of the stator coil conductor increases. Is derived.

  The present invention has been made in view of the above problems, and provides a field coil type rotating electric machine having a Landel type rotor core capable of improving output while suppressing an increase in loss, torque ripple (particularly, tooth torque ripple) and vibration. Its purpose is to provide.

  In order to solve the above-mentioned problems, two independent inventions will be described below with respect to the shape or spatial arrangement of the claw pole portion of the field coil type rotating electrical machine. These two independent inventions have a common invention subject, in particular, reduction of torque ripple and magnetic vibration caused by the arrangement of teeth, and a synergistic teeth torque ripple reduction effect can be achieved by simultaneous implementation. Will be written together.

  The field coil type rotating electrical machine of these two inventions includes a boss portion in which a field coil is wound and a field magnetic flux flows in the axial direction, and a radially outer side at a predetermined circumferential pitch from the axial outer end portion of the boss portion. A plurality of claw pole portions extending in the direction of the axial field coil surroundings, and having a pair of pole cores fitted to the rotating shaft adjacent to each other in the axial direction, And a stator core made of a laminated steel plate having a large number of teeth arranged in the circumferential direction at a constant tooth pitch, and the radially outer end surface of each claw pole portion is formed by connecting the radially inner end surfaces of the teeth. The present invention is applied to a field coil type rotating electrical machine that constitutes a claw pole magnetic pole surface formed with a small diameter by a predetermined small gap with respect to the inner peripheral surface of the stator core. This type of field coil type rotating electrical machine is widely used as a vehicular AC generator and is well known, and thus the description thereof is omitted.

  The field coil type rotating electrical machine according to the first aspect of the present invention is the odd-numbered magnetic pole between the magnetic pole center of the even-numbered claw pole magnetic pole surface and the magnetic pole center of the odd-numbered claw-pole magnetic pole face adjacent to one side in the circumferential direction. The center pitch (P1) is the even-numbered pole center pitch (P2) between the magnetic pole center of the even-numbered claw pole magnetic pole surface and the magnetic pole center of the odd-numbered claw pole magnetic pole face adjacent to the other circumferential side. It is characterized by being displaced by a predetermined width 2τ. In addition, the magnetic pole center said here says a magnetic center.

  Thus, it was found that torque ripple and magnetic vibration characteristics can be greatly reduced. More specifically, since the teeth are arranged in the circumferential direction at the tooth pitch (Pt), the magnetoresistance change Rx between the teeth and the nail pole part from the odd-numbered nail pole part to the next even-numbered nail pole part and The torque ripple and the magnetic vibration are generated by the magnetic resistance change Ry between the teeth and the claw pole part from the even-numbered claw pole part to the next odd-numbered claw pole part. Since the circumferential widths of Rx and Ry are different, eventually the torque ripple and magnetic vibration are the sum of a plurality of frequency components. For this reason, the average value of this sum is reduced compared with the case where the nail pole part pitch between each nail pole part is equal. This was proved by simulation and experiment.

  In a preferred aspect, the predetermined width 2τ is set to 0.8 to 1.2 times the teeth pitch (Pt). Thereby, it turned out that the torque ripple and magnetic vibration resulting from arrangement | positioning of the circumferential direction constant pitch of teeth are reduced favorably.

  In a more preferred aspect, the predetermined width 2τ is set to 0.9 to 1.1 times the teeth pitch (Pt). As a result, it has been found that torque ripple and magnetic vibration caused by the constant circumferential pitch arrangement of the teeth are further reduced.

  In the field coil-type rotating electrical machine according to the second aspect of the invention, the center of one axial half of each claw pole magnetic pole surface is circumferentially the same as the center of the other axial half of each claw pole magnetic pole face. The feature is that the direction is deviated by a predetermined circumferential width. That is, the field coil type rotating electrical machine having the Landel type rotor core according to the present invention is such that the axial one end side half of each claw pole magnetic pole surface is offset in the same direction in the circumferential direction than the axial other end side half. There is the feature. It should be noted that when the claw pole protrudes from one axial end side (hereinafter also referred to as the front end side) to the other axial end side (hereinafter also referred to as the rear end side), the axial one end side half The part means the half part on the proximal end side of the nail pole part (also referred to as the nail pole), and the half part on the other end side in the axial direction means the half part on the tip side of the nail pole part (also called the nail pole). Conversely, when the claw pole protrudes from the other axial end side (rear end side) to one axial end side (front end side), the first axial end half is the tip of the claw pole part (also referred to as the claw pole). The other half in the axial direction means the half on the base end side of the claw pole (also referred to as claw pole).

  In other words, when the claw pole part of the pole core on one end side in the axial direction is called the front claw pole and the claw pole part of the pole core on the other end side in the axial direction is called the rear claw pole, the front half of the front claw pole is the base end. The first half of the rear claw pole is displaced to the other half in the circumferential direction with respect to the second half. As a result, each claw pole portion is skewed, so that the change in the linkage amount of the stator coil with respect to the field flux of one claw pole portion becomes slow, and torque ripple and magnetic vibration can be reduced. Moreover, the tooth torque ripple resulting from the circumferential arrangement of the teeth and slots can be reduced. Note that the present invention is essentially the same as skewing the teeth made of laminated steel sheets, but the stator assembly process is simplified while the skew is imparted to the teeth. The advantage is that the coil conductor length does not increase. In general, since the claw pole portion of the rotor core is forged integrally with the boss portion, the increase in the process due to the above shape can be almost ignored.

  Further, due to the effect of reducing the torque ripple, the circumferentially developed shape of the claw pole magnetic pole surface of each claw pole part of the present invention can be made into a rectangular shape with one side extending in the axial direction. The magnetic pole surface area of the part can be increased. As a result, output can be increased. Furthermore, since it is not necessary to trapezoidally form the claw pole portion for reducing torque ripple as in the prior art, an increase in eddy current due to a component flowing in the axial direction in the stator core (also referred to as an axial component) can be reduced, Iron loss can also be reduced.

  In a preferred aspect, the center of the half end of each claw pole magnetic pole surface in the axial direction is substantially the same as the center of the teeth pitch in the same circumferential direction than the center of the half end of the claw pole magnetic pole surface in the other axial direction. It is displaced by a circumferential width equal to half (more specifically, 0.4 to 0.6 times the teeth pitch (Pt)). Thereby, since the first half part and the second half part of the claw pole part are substantially in reverse phase, torque ripple and vibration caused by the tooth pitch can be greatly reduced.

  In a preferred aspect, the axial one end side half of each claw pole is located at one end side in the circumferential direction and is recessed radially inward from the claw pole magnetic pole surface by a predetermined depth. The other end half in the direction is located on the other end side in the circumferential direction and is recessed radially inward by a predetermined depth from the claw pole magnetic pole surface. As a result, the radially inner portion of each claw pole portion does not cause the axial front half portion of the claw pole portion to be displaced in the circumferential direction with respect to the axial rear half portion. The cross-sectional area perpendicular to the magnetic path at the boundary between the two portions is not reduced, and the flow of field flux is not hindered. Moreover, since the said recessed part can be easily implemented by a normal forging process, the increase in a manufacturing process can also be avoided.

  In a preferred aspect, each of the claw poles has a substantially rectangular circumferential development shape that is long in the axial direction. As a result, as described above, the field flux generation amount per nail pole portion can be increased, and the torque and output can be increased.

  In a preferred aspect, at least the radially outer portions of the claw poles are arranged in parallel to each other, and are inclined with respect to the circumferential direction and the axial direction, respectively. In short, the circumferentially developed shape of the magnetic pole surface (claw pole magnetic pole surface) of the claw pole portion (claw pole) of this aspect is a parallelogram shape. Thereby, like the above, torque ripple can be reduced while increasing the amount of field flux generated per nail pole.

  In a preferred aspect, the teeth of the stator core are obliquely arranged in the circumferential direction opposite to the oblique direction of the claw pole. In this way, even if the circumferentially inclined angle (skew angle) of the teeth and the circumferentially inclined angle (skew angle) of the claw poles are not increased, the relative angle between the teeth and the claw poles can be increased. Since the skew angle can be increased, the torque ripple and the magnetic vibration can be reduced while facilitating the manufacture and suppressing the decrease in the anti-centrifugal performance of the claw pole.

  In a preferred aspect of the second invention, the odd-numbered magnetic pole center pitch between the magnetic pole center of the even-numbered claw pole magnetic pole surface and the magnetic pole center of the odd-numbered claw-pole magnetic pole face adjacent to one side in the circumferential direction ( P1) is greater than the even-numbered magnetic pole center pitch (P2) between the magnetic pole center of the even-numbered claw pole magnetic pole surface and the magnetic pole center of the odd-numbered claw-pole magnetic pole face adjacent to the other circumferential side. It is displaced by a width 2τ. That is, the first invention and the second invention are carried out simultaneously. In this way, the effects of both the inventions can be achieved simultaneously, and the predetermined frequency component of the torque ripple remaining after the implementation of the first invention and the predetermined frequency component of the torque ripple remaining after the implementation of the second invention are in an opposite phase relationship. It was found that torque ripple can be further reduced because of the effect of canceling out. That is, by simultaneously carrying out the first invention and the second invention, a difference occurs in the change in the linkage amount of the stator coil with respect to the field magnetic flux of the adjacent claw pole portions, and the torque ripple and magnetic vibration are satisfactorily reduced. I found out that I could do it.

  In a preferred aspect of the second invention, the predetermined width 2τ is set to 0.8 to 1.2 times the teeth pitch (Pt). As a result, the field flux ripple due to the teeth pitch is substantially opposite in phase between the adjacent nail poles, and it has been found that the torque ripple can be reduced satisfactorily.

  In a further preferred aspect of the second invention, the predetermined width 2τ is set to 0.9 to 1.1 times the teeth pitch (Pt). As a result, it was found that the torque ripple can be further reduced.

(Other aspects)
In addition, as in the prior art, permanent magnets may be inserted in the circumferential gaps between the claw pole portions, and a protective cover for holding the permanent magnets may be provided on the rotor core.

  Hereinafter, a preferred embodiment of a field coil type rotating electrical machine of the present invention will be specifically described with reference to the drawings. However, the present invention is not limited to the following embodiments, and the technical idea of the present invention may be realized by combining other known techniques or other techniques having necessary functions equivalent thereto.

Example 1
(Overall structure)
A vehicular AC generator that employs the Landell rotor core according to the first embodiment will be described with reference to FIG. FIG. 1 is a half sectional view in the axial direction of a main part of the AC generator for a vehicle.

  In FIG. 1, 1 is a rotor, 2 is a stator, 3 is a motor frame, 4 is a rotor core, 5 is a field coil, 6 is a rotating shaft, 7 is a stator core, and 8 is a stator coil. The rotor 1 is formed by winding a field coil 5 around a rotor core 4. The rotor 1 is fitted on the rotary shaft 6. The stator 2 is formed by winding a stator coil 8 around a stator core 7 made of a laminated steel plate, and the stator 2 is fixed to the inner peripheral surface of the peripheral wall portion of the motor frame 3. The rotor 1 is disposed on the radially inner side of the stator 2 and has a so-called inner rotor structure. The rotating shaft 6 is rotatably supported by end wall portions on both sides of the motor frame 3 via unillustrated bearings.

  The rotor core 4 has a so-called Landel type rotor core structure. That is, the rotor core 4 is fitted to the rotating shaft 6 with the pole cores 4A and 4B made of mild steel being adjacent to each other in the axial direction. The pole core 4A is composed of one cylindrical boss portion 41A, N (N is a natural number of 2 or more) disk portion 42A, and N (N is a natural number of 2 or more) claw pole portion 43A. . However, in the description so far, the disk portion 42A and the claw pole portion 43A are defined as “claw pole portions”. Similarly, the pole core 4B is composed of one cylindrical boss portion 41B, N (N is a natural number of 2 or more) disk portion 42B, and N (N is a natural number of 2 or more) claw pole portion 43B. ing. However, in the description so far, the disk portion 42B and the claw pole portion 43B are defined as “claw pole portions”.

  The disk portions 42A and 42 protrude from the outer ends in the axial direction of the boss portions 41A and 41B outward in the radial direction at a constant pitch in the circumferential direction. The claw pole portions 43A and 43B extend from the radially outer ends of the disk portions 42A and 42B toward the axial field coil enclosure. Of the radially outer end surfaces of the claw pole portions 43A and 43B, a region existing on the radially inner side of the stator core 7 is called a claw pole magnetic pole surface, and exchanges magnetic flux with unillustrated teeth of the stator core 7. That is, the area | region which overlaps with the axial direction length L of the stator core 7 comprises the claw pole magnetic pole surface among claw pole parts 43A and 43B. As is well known, the claw pole part 43A of the pole core 4A and the claw pole part 43B of the pole core 4B are approximately half the circumferential pitch of the claw pole part, preferably 0.4 to the circumferential pitch of the claw pole part. The displacement is 0.6 times more preferably 0.45 to 0.55 times in the circumferential direction. When a direct current is applied to the field coil 5, a field flux that reverses for each pitch of the claw pole portions is applied to the stator core 7, and the stator coil 8 is linked to this field flux. Since the structure described above is well known as a field coil type rotating electrical machine having a Landel rotor structure, further description is omitted.

(Detailed shape of the nail pole portions 43A and 43B)
Next, the shape of the claw pole portions 43A and 43B that characterize this embodiment will be described in detail with reference to FIGS. FIG. 2 is a schematic circumferential development view of the claw pole magnetic pole surface, and FIG. 3 is a circumferential development radial cross-sectional view of the claw pole portion. That is, (A-A) is a cross-sectional view taken along line AA in FIG. 2, and FIG. 3 (B-B) is a cross-sectional view taken along line BB in FIG. However, FIG. 2 shows only the region of the claw pole portions 43A and 43B that can face the inner peripheral surface of the stator core 7 (that is, the claw pole magnetic pole surface referred to in the present invention) developed in the circumferential direction.

  In FIG. 2, the claw pole portion 43A and the claw pole portion 43B are arranged in the circumferential direction (PH). P1 is the odd-numbered magnetic pole center pitch (P1), and P2 is the even-numbered magnetic pole center pitch. The magnetic pole center here refers to the magnetic center of the magnetic pole surface of the claw pole portion, particularly in the circumferential direction.

  In this embodiment, a recess 45 is formed in the front half of the claw pole magnetic pole surface 44, and a recess 46 is formed in the rear half of the claw pole magnetic pole surface 44. It should be noted that the recess 45 is formed on the proximal end side of the claw pole portion 43A and is formed on the distal end side of the claw pole portion 43B. Similarly, the recess 46 is formed on the distal end side of the claw pole portion 43A and is formed on the proximal end side of the claw pole portion 43B. The concave portion 45 is formed so as to drop a corner portion on one side in the circumferential direction among the front half portions of the claw pole portions 43A and 43B. Similarly, the recessed part 46 is formed so that the corner | angular part of the circumferential direction other side may be dropped among the latter half parts of the nail | claw pole part 43A, 43B. In this embodiment, the circumferential widths of the recesses 45 and 46 are formed to be about 1/3 of the circumferential width of the claw pole magnetic pole surfaces 44 of the claw pole parts 43A and 43B that are formed in a rectangular shape and extend in the axial direction. ing. Of course, the circumferential width of the recesses 45 and 46 can be set as appropriate. The radial depths of the recesses 45 and 46 are set to be 10 times or more the radial width of the electromagnetic gap between the claw pole magnetic pole surface 44 and the radial inner peripheral surface of the stator core 7, but can be set as appropriate. is there.

  By setting the positions of the pole cores 4A and 4B, the center n2 of the claw pole portion 43B in the circumferential direction of the claw pole magnetic pole surface is the center n1 of the claw pole portion 43A in the circumferential direction of the claw pole magnetic pole surface and the claw pole of the claw pole portion 43A. It is shifted from the original center Q in the circumferential direction of the magnetic pole surface by a width τ corresponding to half the teeth pitch (Pt) in the circumferential direction.

  Thereby, torque ripple (and magnetic vibration) components generated by the claw pole portions 43A and 43B out of the torque ripple (magnetic flux ripple) due to the tooth pitch cancel each other.

  Further, by setting the recesses 45 and 46, the center m1 of the front half of the claw pole magnetic pole surface 44 of the claw pole portions 43A and 43B is relative to the center m2 of the rear half of the claw pole magnetic pole surface 44 of the claw pole portions 43A and 43B. Therefore, it is shifted in the circumferential direction by half the teeth pitch.

  Thereby, of the torque ripple (magnetic flux ripple) caused by the tooth pitch, the torque ripple (and magnetic vibration) component generated by the rotation of the first half of the claw pole portions 43A and 43B and the rotation of the second half of the claw pole portions 43A and 43B. The torque ripple (and magnetic vibration) components generated by the above are out of phase and cancel each other out.

  The simulation result will be described with reference to FIG.

  In this simulation, the torque ripple when the pitch and shape of the claw pole part are changed by simulation is obtained by using each claw pole part magnetic pole face whose circumferentially developed shape is rectangular and without teeth skew. It is.

  2, the circumferential center n2 of the claw pole portion 43B in FIG. 2 coincides with the Q point, and the circumferential center m1 of the front half of each claw pole portion and the circumferential direction of the rear half of the axial direction. The teeth torque ripple waveform in the case where the center m2 is equal to the circumferential direction, that is, the conventional claw pole part structure is shown.

  In FIG. 2, τ is set to half of the teeth pitch (Pt) in FIG. 2, and the circumferential center m1 of the first axial half of each claw pole portion and the circumferential center m2 of the second axial half are circumferential. The teeth torque ripple waveform in the case where the position is equal to the direction is shown.

  In FIG. 2, τ is set to half of the teeth pitch (Pt) in FIG. 2, and the circumferential center m1 of the first axial half and the circumferential center m2 of the second axial half of each claw pole portion are circumferential. The tooth torque ripple waveform is shown in the case of deviation by τ.

  From FIG. 9, it was found that torque ripple can be greatly reduced by setting τ to half of the teeth pitch (Pt). Furthermore, τ is set to half of the teeth pitch (Pt), and the circumferential center m1 of the axial front half of each claw pole and the circumferential center m2 of the axial rear half are shifted in the circumferential direction by τ. It has been found that the torque ripple can be further reduced by making it.

  FIG. 9 shows an example of the simulation result, and τ is set to 0.4 to 0.6 times, more preferably 0.45 to 0.55 times the teeth pitch (Pt). It has been found that the above-described torque ripple reduction effect and magnetic vibration reduction effect can be obtained.

  More specifically, when the odd-numbered nail pole pitch and the even-numbered nail pole pitch are changed among the nail pole pitches, which are circumferential intervals between two adjacent nail poles, As described above, the Nth (N is a natural number) nail pole pitch, the (N + 1) th nail pole pitch, and the (N + 2) th nail pole pitch may be different. Further, the N (N is a natural number) nail pole pitch, the (N + 1) th nail pole pitch, the (N + 2) nail pole pitch, and the (N + 3) nail pole pitch may be different.

  The reason why the torque ripple can be reduced when the odd-numbered nail pole portion pitch and the even-numbered nail pole portion pitch are changed will be further described below by taking, for example, the power generation action as an example. Let P be the generated power. The torque T is equal to P / ω, and P can be regarded as equal to V · V / r. V is a generated voltage and r is a load resistance. V is a generated voltage and is proportional to a change in the coil linkage magnetic flux φ. Here, it is assumed that the magnetic flux φ is a transfer magnetic flux between the claw pole portion and one tooth. If the magnetic flux between each odd-numbered tooth and the claw pole portion is φ1, and the magnetic flux between each even-numbered tooth and the claw pole portion is φ2, changes in φ1 and φ2 having different phases (d (φ1 + φ2 Therefore, the torque acting on one tooth is proportional to the square of the amount of change in teeth magnetic flux (d (φ1 + φ2) / dt), that is, φ1, If φ2 is a function of a sine wave, the square value of (d (φ1 + φ2) / dt) can be increased by changing the odd-numbered nail pole pitch and the even-numbered nail pole pitch. It is expected that torque ripple is reduced as a whole by canceling out each harmonic component including several components.

  In addition, in this embodiment, since the claw pole portions 43A and 43B extend in the axial direction and the claw pole magnetic pole surface 44 has a rectangular shape, the field flux generated by one claw pole magnetic pole surface 44 is increased. Can do. As a result, the motor output can be improved. Further, in this embodiment, the circumferential widths of the claw pole portion 43A and the claw pole portion 43B are substantially equal in each axial portion. For this reason, for example, the field magnetic flux that has entered one steel plate of the stator core 7 from the claw pole portion 43A can flow in the steel plate in the circumferential direction and the radial direction, and can flow to the claw pole portion 43B. That is, the field magnetic flux component flowing in the axial direction through the stator core 7 made of laminated steel sheets can be greatly reduced. As a result, the iron loss of the stator core 7 can be greatly reduced. On the other hand, in the conventional tapered claw pole magnetic pole surface 440 shown in FIG. 8, the circumferential width L2 of the claw pole portion 43A facing one steel plate 700 of the stator core and the circumferential width of the claw pole portion 43A. Since it is significantly different from L1, in principle, the axial component of the field flux flowing in the axial direction inside the stator core 7 is large. For this reason, a big iron loss generate | occur | produces. In FIG. 8, Wd is the axial width of the disk portion. 3 is a radial cross-sectional view of the claw pole portions 43A and 43B of FIG. 2, (A-A) is a cross-sectional view taken along the line AA of FIG. 2, and (B-B) is a BB line of FIG. FIG. A partial perspective view of one nail pole portion 43A is shown in FIG.

(Embodiment 2)
The nail | claw pole part 43A, 43B of Embodiment 2 is demonstrated with reference to FIG. FIG. 6 is a schematic circumferential development of the claw pole magnetic pole surface. In FIG. 6, Wd is the axial width of the disk portions 42A and 42B, and L is the axial width of the claw pole magnetic pole surface 44 facing the stator core 7 of the claw pole portions 43A and 43B.

  In this embodiment, the claw pole portions 43A and 43B are obliquely provided on one side in the circumferential direction from the front end side toward the rear end side. As a result, the center of the front half of the claw pole magnetic pole surface 44 of the claw pole portions 43A, 43B is shifted by a predetermined width in the circumferential direction with respect to the center of the rear half of the claw pole magnetic pole surface 44 of the claw pole portions 43A, 43B. become. Thereby, the same effect as Embodiment 1 can be produced. Furthermore, according to this embodiment, since the shape of the claw pole portions 43A and 43B is simple, the manufacture of the rotor core 4 is facilitated, and the centrifuge resistance performance of the claw pole portions 43A and 43B is higher than that of the first embodiment. The effect that it can improve can also be show | played.

  In this embodiment as well, the torque ripple reduction effect can be increased by setting τ to, for example, half of the teeth pitch (Pt).

(Embodiment 3)
The nail | claw pole part 43A, 43B of Embodiment 3 is demonstrated with reference to FIG. FIG. 7 is a schematic circumferential development of the claw pole magnetic pole surface. In FIG. 7, Wd is the axial width of the disk portions 42A and 42B, and L is the axial width of the claw pole magnetic pole surface 44 facing the stator core 7 of the claw pole portions 43A and 43B. Reference numeral 100 denotes an imaginary line that indicates the circumferential oblique direction of the teeth of the stator core.

  In other words, in this embodiment, the claw pole portions 43A and 43B are obliquely arranged on one side in the circumferential direction from the front end side toward the rear end side. Further, the teeth of the stator core are obliquely provided on the other side in the circumferential direction from the front end side toward the rear end side. In this way, even if the circumferentially inclined angle (skew angle) of the teeth and the circumferentially inclined angle (skew angle) of the claw pole are not increased, the relative angle between the teeth and the claw pole is increased. Since the skew angle can be increased, the torque ripple and the magnetic vibration can be reduced while facilitating the manufacture and suppressing the decrease in the anti-centrifugal performance of the claw pole.

  In this embodiment as well, the torque ripple reduction effect can be increased by setting τ to, for example, half of the teeth pitch (Pt).

  Preferably, the circumferentially inclined angle (skew angle) of the teeth and the circumferentially inclined angle (skew angle) of the claw pole are approximately equal. Preferably, the positional relationship between the axial rear end of the teeth and the axial rear end of the claw pole is 0.5 to 1 teeth relative to the positional relationship between the axial front end of the teeth and the axial front end of the claw pole. The pitch is off. Thereby, the torque ripple including the tooth torque ripple and the magnetic vibration can be reduced satisfactorily.

1 is a half sectional view in the axial direction of a main part of a vehicular AC generator that employs a Landell rotor core according to Embodiment 1. FIG. It is a model circumferential direction expanded view of the nail | claw pole part of FIG. It is the circumferential direction expansion | deployment radial direction sectional drawing of a nail | claw pole part, (A-A) is the sectional view on the AA line of FIG. 2, (B-B) is a sectional view on the BB line of FIG. It is a fragmentary perspective view of the nail pole part of Drawing 2 and Drawing 3. It is a fragmentary perspective view which shows the deformation | transformation aspect which chamfered the corner | angular part of the nail | claw pole part of FIG. It is a model circumferential direction expanded view of the nail | claw pole part of Embodiment 2. It is a model circumferential direction expanded view of the nail | claw pole part of Embodiment 3. It is a model circumferential direction expanded view of the conventional typical nail pole part. 6 is a torque ripple waveform diagram showing a simulation result showing the torque ripple reduction effect of Example 1. FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Rotor 2 Stator 3 Motor frame 4A Pole core 4B Pole core 4 Rotor core 5 Field coil 6 Rotating shaft 7 Stator core 8 Stator coil 41A Boss part 41B Boss part 42A Disc part 42B Disc part 43A Claw pole part 43B Claw pole part 44 Claw pole pole face 45 recess 46 recess

Claims (12)

A boss portion in which a field coil is wound so that a field magnetic flux flows in the axial direction, and protrudes radially outward at a predetermined circumferential pitch from the axial outer end portion of the boss portion, and then toward the axial field coil surrounding. A Landel rotor having a plurality of claw pole portions each extending, and having a pair of pole cores that are axially adjacent to each other and fitted to the rotating shaft, and a large number arranged in the circumferential direction at a constant tooth pitch A stator core made of a laminated steel sheet having a plurality of teeth, and a radially outer end surface of each claw pole portion has a predetermined small gap with respect to an inner peripheral surface of the stator core formed by connecting a radially inner end surface of the teeth. In the field coil type rotary electric machine that constitutes the claw pole magnetic pole surface formed with a small diameter only,
The odd-numbered magnetic pole center pitch (P1) between the magnetic pole center of the even-numbered claw pole magnetic pole surface and the magnetic pole center of the odd-numbered claw-pole magnetic pole face adjacent to one side in the circumferential direction is the even-numbered claw. Deviation by a predetermined width 2τ from the even-numbered magnetic pole center pitch (P2) between the magnetic pole center of the pole magnetic pole face and the magnetic pole center of the odd-numbered claw pole magnetic pole face adjacent to the other circumferential side. Field coil type rotating electrical machine characterized by In the field coil type rotating electrical machine according to claim 1,
The predetermined width 2τ is a field coil type rotating electrical machine set to 0.8 to 1.2 times the teeth pitch (Pt). In the field coil type rotating electrical machine according to claim 1,
The predetermined width 2τ is a field coil type rotating electrical machine set to 0.9 to 1.1 times the teeth pitch (Pt). A boss portion in which a field coil is wound and the field magnetic flux flows in the axial direction, and protrudes radially outward at a predetermined circumferential pitch from the axial outer end portion of the boss portion, and then toward the axial field coil surrounding. A Landel rotor having a plurality of claw pole portions each extending, and having a pair of pole cores that are axially adjacent to each other and fitted to the rotating shaft, and a large number arranged in the circumferential direction at a constant tooth pitch A stator core made of a laminated steel sheet having a plurality of teeth, and a radially outer end surface of each claw pole portion has a predetermined small gap with respect to an inner peripheral surface of the stator core formed by connecting a radially inner end surface of the teeth. In the field coil type rotary electric machine that constitutes the claw pole magnetic pole surface formed with a small diameter only,
The center of one half of each claw pole magnetic pole surface in the axial direction is deviated by a predetermined circumferential width in the same circumferential direction from the center of the other half of the claw pole magnetic pole surface in the axial direction. A field coil type rotating electrical machine characterized by that. In the field coil type rotating electrical machine according to claim 4,
The center of one half of each claw pole magnetic pole surface in the axial direction is 0.4 in the teeth pitch (Pt) in the same circumferential direction than the center of the other half of the claw pole magnetic pole face in the axial direction. A field coil type rotating electrical machine that is deviated by a circumferential width equal to ˜0.6 times. In the field coil type rotating electrical machine according to claim 4,
One half of each claw pole in the axial direction is located at one end in the circumferential direction and is recessed radially inward by a predetermined depth from the claw pole magnetic pole surface, and the other half in the axial direction of each claw pole. The field coil type rotating electrical machine is located on the other end side in the circumferential direction and is recessed radially inward by a predetermined depth from the claw pole magnetic pole surface. In the field coil type rotating electrical machine according to claim 6,
Each said claw pole is a field coil type rotary electric machine which has the substantially rectangular circumferential direction expansion | deployment shape long in an axial direction. In the field coil type rotating electrical machine according to claim 4,
A field coil type rotating electrical machine in which at least the radially outer portions of the claw poles are arranged in parallel to each other and are obliquely arranged with respect to the circumferential direction and the axial direction, respectively. The field coil type rotating electrical machine according to claim 8,
The field coil type rotating electrical machine in which the teeth of the stator core are obliquely arranged in the circumferential direction opposite to the oblique direction of the claw pole. In the field coil type rotating electrical machine according to claim 4,
The odd-numbered magnetic pole center pitch (P1) between the magnetic pole center of the even-numbered claw pole magnetic pole surface and the magnetic pole center of the odd-numbered claw-pole magnetic pole face adjacent to one side in the circumferential direction is the even-numbered claw. Deviation by a predetermined width 2τ from the even-numbered magnetic pole center pitch (P2) between the magnetic pole center of the pole magnetic pole face and the magnetic pole center of the odd-numbered claw pole magnetic pole face adjacent to the other circumferential side. Field coil type rotating electrical machine characterized by In the field coil type rotating electrical machine according to claim 10,
The predetermined width 2τ is a field coil type rotating electrical machine set to 0.8 to 1.2 times the teeth pitch (Pt). In the field coil type rotating electrical machine according to claim 10,
The predetermined width 2τ is a field coil type rotating electrical machine set to 0.9 to 1.1 times the teeth pitch (Pt).

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