JP2005130692A - Axial-type permanent-magnet motor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an axial-type permanent-magnet motor capable of easily being set to suppress generation of cogging torque, while preventing decrease in the torque of the motor. <P>SOLUTION: In this axial-type permanent-magnet motor, contours 24a, 20a of a coil 24 and a permanent magnet 20 are in such a direction that the direction crosses a rotor rotational direction are set to be approximately a straight-line shape, and the contour 24a of the coil 24 and the contour 20a of the permanent magnet 20 are set so as to contact/separate from each other in a rotor rotating direction in an non-parallel condition, when the rotor rotates. Therefore, when a magnetic pole by the permanent magnet 20 passes through a magnetic pole by the stator coil 24 during the rotation of the rotor, fluctuations in the flux gradually change with the rotational speed of the rotator, so that rapid torque fluctuations are suppressed, and cogging torque is relieved. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to an axial permanent magnet motor in which a magnetic pole of a stator and a permanent magnet of a rotor are arranged to face each other in a direction parallel to the rotation axis, and in particular, an improvement of an axial permanent magnet motor capable of reducing cogging torque generated during motor rotation. About.

  2. Description of the Related Art Conventionally, an axial type permanent magnet motor in which a magnetic pole of a stator and a permanent magnet of a rotor are arranged to face each other in a direction parallel to a rotation axis is known. In the rotor of this axial type permanent magnet motor, for example, as shown in Patent Document 1 and Patent Document 2, a plurality of permanent magnets are arranged in an annular shape on the surface of a rotor core made of soft iron or the like. The magnetic poles of the permanent magnets are alternately arranged so as to be different from the adjacent permanent magnets. Then, by generating a rotating magnetic field in the stator side coil, the magnetization state of the stator teeth sequentially rotates, and magnetic attraction and repulsion occur between the teeth and each permanent magnet. As a result, torque is generated and the rotor is rotated.

  By the way, in the motor, cogging torque, that is, torque fluctuation generated in the motor and periodic fluctuation in speed are generated by the magnetic flux changing when the magnetic pole by the permanent magnet of the rotor passes the magnetic pole by the coil of the stator. This cogging torque appears more prominently as the magnetic flux changes more rapidly.

  Therefore, for example, in the axial type permanent magnet motor described in Patent Document 1, the corners of the permanent magnets arranged on the rotor are shaved in the thickness direction (axial direction), the axial cross section is made substantially trapezoidal, and the magnetic flux rapidly changes. And the occurrence of cogging torque is reduced.

  Further, in the axial type permanent magnet motor described in Patent Document 2, a permanent magnet having a substantially circular cross-section in the rotor rotation direction is used as the rotor magnet, thereby suppressing rapid fluctuations in magnetic flux during rotor rotation and cogging. Occurrence is reduced.

Japanese Patent Laid-Open No. 2001-57753 JP-A-9-191623

  However, in the motor of Patent Document 1 described above, a part of the permanent magnet becomes thin, which causes a direct decrease in the motor torque and requires processing of the permanent magnet, which increases the manufacturing cost. I was invited.

  Further, in the case of the motor of Patent Document 2, since a permanent magnet having a substantially circular cross-sectional shape in the rotor rotation direction is used, the ratio of the area of the permanent magnet on the rotor surface is small, which causes a reduction in motor torque. It was. In addition, the efficient use of the rotor surface has hindered miniaturization of the motor.

  As described above, it is very difficult to set a balance between suppression of cogging torque and securing of motor torque. Therefore, a structure that can easily balance the two has been desired.

  Accordingly, an object of the present invention is to provide an easy-to-set axial permanent magnet motor capable of suppressing the generation of cogging torque while preventing a reduction in motor torque in an axial permanent magnet motor. .

  In the axial type permanent magnet motor according to the present invention, the outline of the coil and the direction intersecting the rotor rotation direction of the magnet has a substantially linear shape, and the outline of the coil and the outline of the magnet at the time of rotation of the rotor are: They are set so as to be close to and away from each other in the rotor rotation direction in a non-parallel state.

  As described above, by forming a contact / separation relationship between the outline of the coil and the outline of the magnet at the time of rotation, the fluctuation of the magnetic flux when the magnetic pole by the permanent magnet of the rotor passes the magnetic pole by the coil of the stator is It gradually changes as the rotor rotates. As a result, rapid torque fluctuation is suppressed and the cogging torque is reduced. Note that the contour line in the direction intersecting the rotor rotation direction of the coil and magnet is substantially straight, does not mean a strict straight line, but may be regarded as a substantial straight line as a whole, It may be curved to some extent, or may include a partially bent portion or a curved portion. Thus, by making the outline of a coil and a magnet into a substantially linear shape, the effective area of a coil and the effective area of a magnet can be increased easily, and it can contribute to torque ensuring.

  At this time, as a method for setting the coil contour line and the magnet contour line so as to be close to and away from each other in the rotor rotation direction in a non-parallel state, for example, the contour lines of the magnets arranged adjacent to each other in the rotor This can be done by setting non-parallel.

  Moreover, it can also be realized by setting the contour lines of adjacently arranged coils in the stator to be non-parallel.

  Further, by making the width in the direction intersecting the rotor rotation direction of the magnet in the rotor and the width in the direction intersecting the rotor rotation direction of the coil in the stator mismatch, the coil contour line and the magnet contour line are obtained. , And can be set so as to be close to and away from each other in the rotor rotation direction in a non-parallel state.

  As described above, when the coil contour line and the magnet contour line are not parallel to each other, the contour line in the direction intersecting the rotor rotation direction of the magnet in the rotor and the rotor rotation direction of the coil in the stator It is desirable to determine the crossing angle of the contour line in the direction intersecting with the balance between the change in the output torque of the motor and the change in the cogging torque. When the crossing angle is increased, the fluctuation time of the magnetic flux becomes longer, so that cogging is further relaxed. On the other hand, if the crossing angle is increased, the amount of magnetic flux linkage that contributes to the generation of the magnet torque is reduced, so that the cogging torque can be suppressed, but the overall magnet torque is slightly reduced. Therefore, it is desirable to determine the crossing angle of each contour line according to the application of the axial permanent magnet motor.

  In the configuration for suppressing the cogging torque as described above, a reluctance torque is generated between the magnetic body of the rotor and the magnetic pole on the stator side by disposing a magnetic body between adjacent magnets in the rotor. Can be generated. As a result, the total torque of the axial permanent magnet motor can be improved while suppressing the cogging torque.

  In addition, the contour line of the rotor magnet is substantially fan-shaped, the gap between adjacent rotor magnets is rectangular, the contour line of the stator coil is substantially fan-shaped, and the gap between adjacent stator coils is The ratio of the circumferential gap between the rotor magnets to the circumferential gap between the stator coils is preferably 2.4 to 3.2.

  In addition, the contour line of the rotor magnet is substantially fan-shaped, the gap between adjacent rotor magnets is rectangular, the contour line of the stator coil is substantially fan-shaped, and the gap between adjacent stator coils is The ratio of the circumferential gap between the rotor magnets to the circumferential gap between the stator coils is preferably 2.2 to 3.4.

  In addition, the contour line of the stator coil and the rotor magnet is substantially fan-shaped, the angle α with respect to a straight line perpendicular to the radial direction of the rotor with respect to the contour line in the direction intersecting the rotor rotation direction of the rotor magnet, and the stator coil It is preferable that the ratio α / θ of the contour line in the direction intersecting with the rotor rotation direction to the angle θ with respect to the straight line in the radial direction of the rotor is in the range of 0.86 to 0.89.

  By making the shape and arrangement of the stator coil and the rotor magnet as described above, the cogging torque can be reduced while maintaining the output torque (number of flux linkages) of the motor.

  Hereinafter, embodiments of the present invention (hereinafter referred to as embodiments) will be described with reference to the drawings.

  FIG. 1 is a schematic configuration diagram showing the whole of the axial permanent magnet motor 10 of the present embodiment, FIG. 2 shows only the stator 12 of the axial permanent magnet motor 10, and FIG. 3 shows only the rotor 14. Is illustrated. As shown in FIG. 1, the axial permanent magnet motor 10 has a rotor 14 fixed to a rotating shaft 18 that is rotatably supported by a casing 16. As shown in FIG. 3, the rotor 14 has a substantially disk shape, and the permanent magnets 20 are concentrically arranged in the circumferential direction. The permanent magnet 20 may be completely embedded in the rotor 14, or may be arranged so that the surface is a part of the surface of the rotor 14. At this time, the adjacent permanent magnets 20 are arranged so that “S pole” and “N pole” are alternately arranged on the same plane.

  On the other hand, a substantially annular stator 12 is arranged inside the casing 16 so as to sandwich it from the front and back of the disk-shaped rotor 14. The stator 12 is configured around a stator core 12a as shown in FIG. 2A, and a plurality of teeth 22 project from a surface facing the rotor. As shown in FIG. 2B, a conductive wire is wound around each tooth 22 to form a coil 24, and a magnetic pole is formed by flowing current therethrough. That is, the stator 12 is formed by the stator core 12 a and the coil 24. Thus, the axial permanent magnet motor 10 is arranged such that the magnetic poles of the stator 12 and the permanent magnet 20 of the rotor 14 face each other in a direction parallel to the rotating shaft 18 that is the rotating shaft of the motor.

  Then, the teeth 22 are sequentially magnetized by sequentially passing current through the coil 24, and a rotating magnetic field is formed. Then, the permanent magnet 20 of the rotor 14 interacts with the rotating magnetic field to cause attraction and repulsion, and the rotor 14 rotates to obtain magnet torque. The basic configuration of the axial permanent magnet motor 10 described above is common to the embodiments described below.

  In the present embodiment, the contour lines in the direction intersecting the rotor rotation direction of the coil 24 of the stator 12 and the permanent magnet 20 of the rotor 14 are substantially linear as shown in FIG. Sometimes, the outline 24a of the coil 24 and the outline 20a of the permanent magnet 20 are set so as to be in contact with and away from each other in the rotor rotation direction in a non-parallel state. In the case of FIG. 4, the outlines 24a of the adjacent coils 24 are arranged in parallel, and the outlines 20a of the adjacent permanent magnets 20 are arranged non-parallel. In the case of FIG. 4, only the outline of the permanent magnet 20 is shown in order to clarify the positional relationship with the coil 24. By making the outlines 24a and 20a of the coil 24 and the permanent magnet 20 substantially linear, the effective area of the coil 24 and the effective area of the permanent magnet 20 can be easily increased. In other words, it is easy to increase the chance of crossing the magnetic flux, which can contribute to securing the torque. It should be noted that the outlines 20a and 24a being substantially straight does not mean a strict straight line, but may be regarded as a substantially straight line as a whole, and may be curved to some extent, partially bent, A curved portion may be included.

  In a state where the positional relationship between the coil 24 and the permanent magnet 20 is formed, as described above, the rotor 14 is rotated by passing a current sequentially through the coil 24. At this time, as apparent from FIG. 4, when the rotor 14 rotates in the direction of arrow A, the contour 24 a of the coil 24 and the contour 20 a of the permanent magnet 20 always intersect with each other while having a predetermined angle. Become. That is, the fluctuation of the magnetic flux when the magnetic pole by the permanent magnet 20 of the rotor 14 passes the magnetic pole by the coil 24 of the stator 12 gradually changes as the rotor 14 rotates.

  If the outline 24a of the coil 24 and the outline 20a of the permanent magnet 20 pass in a parallel state, as shown in FIG. 5A, the number of magnetic flux intersections reaches a certain rotation angle. It increases rapidly from the state of “0”. That is, the fluctuation of the magnetic flux suddenly occurs and the cogging torque appears remarkably. On the other hand, as shown in FIG. 4, when the rotor 14 rotates in the direction of arrow A, the contour 24a of the coil 24 and the contour 20a of the permanent magnet 20 always intersect with each other while having a predetermined angle. By setting the relationship, the coil 24 and the permanent magnet 20 gradually intersect, and as shown in FIG. 5B, the number of magnetic flux linkages gradually increases as the rotor 14 rotates, and reaches the maximum. Then gradually decrease again. As a result, the cogging torque generated due to the rapid fluctuation of the magnetic flux is suppressed. In each phase, the axial permanent magnet motor 10 can be smoothly rotated by suppressing the cogging torque.

  FIG. 6 shows an example of setting each contour line for intersecting the contour line 24a of the coil 24 and the contour line 20a of the permanent magnet 20 while always having a predetermined angle.

  For example, in the case of FIG. 6A, the setting shown in FIG. 4 is shown for the entire circumference. In other words, the outer shape of the permanent magnet 20 is set so that the contour line 20 a of the adjacent permanent magnet 20 (shown by a thick line) is non-parallel, and the permanent magnet 20 is arranged in the circumferential direction of the rotor 14. On the other hand, the outer shape of the coil 24 is set and arranged in the circumferential direction of the stator 12 so that the outline 24a of the adjacent coil 24 (illustrated by a thin line) is parallel. As apparent from FIG. 6A, when the rotor 14 supporting the permanent magnet 20 rotates, the contour lines 20a and 24a always come in contact with and separate from the oblique direction.

  In the case of FIG. 6B, the outer shape of the permanent magnet 20 is set and arranged so that the contour line 20a of the adjacent permanent magnet 20 (shown by a bold line) is non-parallel. Further, the outer shape of the coil 24 is set and arranged so that the contour line 24a of the adjacent coil 24 (illustrated by a thin line) is also non-parallel. Also in this case, when the rotor 14 rotates, the contour lines 20a and 24a always come in and out of the oblique direction. In the case of FIG. 6C, the outer shape of the permanent magnet 20 is set and arranged so that the contour line 20a of the adjacent permanent magnet 20 (thick line) is parallel. On the other hand, the outer shape of the coil 24 is set and arranged so that the outline 24a of the adjacent coil 24 (thin line) is non-parallel. Also in this case, when the rotor 14 rotates, the contour lines 20a and 24a always come in and out of the oblique direction.

  In the case of FIG. 6D, the outer shape of the permanent magnet 20 is set and arranged so that the contour line 20a of the adjacent permanent magnet 20 (thick line) is parallel. Further, the outer shape of the coil 24 is set and arranged so that the contour line 24a of the adjacent coil 24 (illustrated by a thin line) is also parallel. In this case, however, the width of the rotor 14 in the direction intersecting with the rotor rotation direction of the permanent magnet 20 (for example, the outermost width) and the width of the coil 24 in the stator 12 in the direction intersecting with the rotor rotation direction (for example, the outermost contour). Width) is set to be inconsistent (in the case of FIG. 6D, the width of the permanent magnet 20 is wider). In this case, as is clear from FIG. 7 showing the relative position change during the rotation of the rotor 14, the contour lines 20a and 24a are always contacted and separated from the oblique direction.

  Thus, by making the adjacent outlines 24a of the coils 24 of the stator 12 or the adjacent outlines 20a of the permanent magnet 20 of the rotor 14 non-parallel, the outline 20a and the outline 24a are When the rotor 14 rotates, the rotor 14 comes in contact with and away from the rotor in the non-parallel state, and the above-described cogging torque suppression effect is generated.

  In the examples shown in FIGS. 6A to 6C, it is desirable to appropriately select the intersection angle between the contour line 20 a and the contour line 24 a according to the performance required for the axial permanent magnet motor 10. In other words, if the crossing angle is set to be large, the fluctuation of the magnetic flux gradually occurs, so that the generation of cogging torque is suppressed satisfactorily. However, in order to increase the crossing angle, the planar shape of the permanent magnet 20 and the coil 24 is an acute angle part. It will move to a shape that includes. That is, as a result, the area of at least one of the permanent magnet 20 or the coil 24 is reduced, and the overall motor torque is reduced. On the other hand, if the crossing angle is set small, the change in the area of the permanent magnet 20 and the coil 24 can be reduced, so that the motor torque decreases slightly. However, compared to the case where the crossing angle is set large, the magnetic flux is reduced. Since the fluctuation becomes large, the cogging torque suppressing force is reduced. In the case of motors, depending on the application, there are cases where importance is placed on securing motor torque, and there are cases where importance is placed on smoothness of rotation, so it is suitable for the application by selecting the appropriate crossing angle according to the intended use of the motor. Further, the axial type permanent magnet motor 10 can be obtained.

  Incidentally, in the case of the present embodiment, as is apparent from FIG. 6 and the like, the permanent magnets 20 arranged concentrically in the rotor 14 are arranged at a predetermined interval. Of course, when the contour line 20a of the adjacent permanent magnet 20 is set to be non-parallel, an interval is necessarily required. Therefore, in the present embodiment, as shown in FIG. 8, the magnetic body 26 is disposed in at least a space formed between the permanent magnets 20. By disposing the magnetic body 26 between the permanent magnets 20, the magnetic body 26 is attracted to the magnetic poles sequentially formed on the stator 12 to rotate the rotor 14. That is, it can contribute to generation of reluctance torque. Therefore, the resultant force of the magnet torque and the reluctance torque can be used as the motor torque of the axial permanent magnet motor 10.

  As a result, for example, as shown in FIGS. 6A and 6B, when the contour lines 20a of the adjacent permanent magnets 20 are set so as to be non-parallel to each other, the substantial area of the permanent magnet 20 is reduced. Although the magnetic torque decreases and the magnet torque decreases, the decrease can be compensated by the reluctance torque generated by the magnetic body 26 interposed between the permanent magnets 20, or can be increased beyond the decrease. As a result, it is possible to maintain and improve the motor torque while suppressing the cogging torque. Of course, the magnetic material may be disposed not only between the permanent magnets 20 but also on the surface of the permanent magnet 20 (for example, coating of the magnetic material).

  In the case of the axial permanent magnet motor 10, the magnetic flux is directed in a direction parallel to the rotating shaft 18, but when the magnetic body 26 exists between the adjacent permanent magnets 20 as described above, a vortex is generated in the magnetic body 26. An electric current will be generated. The generation of eddy current causes energy loss such as heat generation. Therefore, in order to suppress the generation of eddy current, it is desirable to set the electric resistance of the magnetic body 26 in the plane orthogonal to the magnetic flux high. As a method of setting the electric resistance high, for example, a thin silicon steel plate can be stacked along the radial direction of the rotor 14, that is, along the plane orthogonal to the magnetic flux to form the core of the rotor 14. . In this case, the permanent magnet 20 is formed by slicing a circular core formed by winding a silicon steel plate, forming a recess for housing the permanent magnet 20 therein, and re-slicing the sliced core by welding or the like. As a result, the permanent magnet 20 can be disposed on the rotor 14 and the magnetic body 26 can be substantially disposed.

  As another method, for example, there is a method of forming a rotor core from a powder magnetic core material obtained by compacting a powder coated with a film that does not conduct electricity on the surface of a ferromagnetic fine particle such as iron. The rotor core formed of the dust core material allows magnetic flux to pass in a three-dimensional direction, but hardly passes current, and therefore does not flow eddy current even when receiving a magnetic field generated by the stator 12. On the other hand, like the rotor core formed by stacking silicon steel plates, eddy current can be suppressed satisfactorily. In this case, since the permanent magnet 20 can be embedded when the powder magnetic core material is pressed and hardened, the permanent magnet 20 and the magnetic body 26 can be easily arranged in the rotor 14. In addition, when forming a core using a silicon steel plate or a powder magnetic core material, it is desirable to perform reinforcement for maintaining the rigidity of the core as necessary.

  The configuration shown in the present embodiment is an example, and the outlines 24a and 20a in the direction intersecting the rotor rotation direction of the coil 24 and the permanent magnet 20 are substantially linear, and further, when the rotor 14 is rotated, they are not mutually non-rotating. The effect similar to that of the present embodiment can be obtained as long as it is set so as to contact and separate in the rotor rotation direction in a parallel state.

  Furthermore, the influence of the shape of the gap between the coils 24 (slot opening) in the stator 12 and the gap (saliency pole) between the permanent magnets 20 of the rotor 14 on the cogging torque and the number of magnet linkages was investigated.

  FIG. 9 shows a schematic diagram of the stator 12 and the rotor 14. In the stator 12, substantially fan-shaped coils 24 are arranged at equal intervals on the circumference. A gap (slot opening) in the circumferential direction between the coils 24 is rectangular, and the width in the circumferential direction is constant. In addition, the rotor 14 is provided with substantially fan-shaped permanent magnets 20 arranged at equal intervals on the circumference, and the circumferential gaps (saliency poles) between the permanent magnets 20 are also rectangular. The width of is constant.

  Using the stator 12 and the rotor 14 as described above, the ratio of the salient pole width to the slot opening portion (the salient pole width / slot opening width) was changed, and the results of obtaining the cogging torque and the number of magnet linkages are shown in FIGS. Shown in Here, the cogging torque and the number of magnet linkages are both normalized values, and the number of magnet linkages is the number of linkage fluxes for the magnetic flux of the permanent magnet 14.

  From FIG. 10, it can be seen that the cogging torque when the salient pole width / slot width is changed takes a minimum value near 2.8. In particular, when the salient pole width / slot width is in the range of 2.2 to 3.4, the cogging torque can be suppressed to a very small value, which is preferable. More preferably, it is 2.4-3.2.

  Further, as shown in FIG. 11, when the salient pole width / slot width is increased, the number of interlinkage of magnets slightly decreases. However, within the above range of salient pole width / slot width of 2.2 to 3.4. The decrease range is small, and it can be seen that the cogging torque can be greatly reduced while suppressing the decrease in the output torque within this range. More preferably, it is 2.4-3.2.

  FIG. 12 shows the stator tilt angle and the rotor tilt angle. The stator inclination angle θ is an angle with respect to a line orthogonal to the radius of the left and right sides of the coil 24 of the stator 12. Further, the rotor inclination angle α is an angle with respect to a line orthogonal to the radius of the left and right sides of the contour of the permanent magnet coil 24 of the rotor 14.

  FIG. 13 shows the relationship between α / θ and the standard value of the number of magnet chain intersections and the standard value of cogging torque. Thus, by increasing α / θ, the number of magnet linkages and the cogging torque increase. However, the increase in cogging torque with respect to the increase in α / θ is relatively slow in the increase in the number of magnet linkages. That is, as α / θ is increased, the number of magnet linkages starts to rise immediately, but the number of magnet linkages does not rise much at first. Therefore, when α / θ is in the range of 0.86 to 0.89, the cogging torque can be suppressed to a relatively small value while maintaining the number of magnet linkages at a relatively large value. Note that when α / θ is made not more than the above range, only the number of magnet linkages is decreased, and the cogging torque is not decreased. Further, if α / θ is set to the above range or more, the cogging torque becomes considerably large, while the increase in the number of magnet linkages is small. Therefore, as described above, in order to increase the number of magnet linkages and suppress the cogging torque to be small, α / θ is preferably in the range of 0.86 to 0.89.

  FIG. 13 shows the results of an experiment conducted with the slot width / saliency pole width = 0.3 viewed from the inner diameter of the permanent magnet 24 and the average radius of the outer shape.

It is explanatory drawing explaining the structure of the axial type permanent magnet motor of this embodiment. It is explanatory drawing explaining the state which mounted | wore the shape of the stator core of the axial type permanent magnet motor of this embodiment, and the coil. It is explanatory drawing explaining the structure of the rotor of the axial type permanent magnet motor of this embodiment. It is explanatory drawing explaining the intersection state of the contour line of the permanent magnet of the rotor of the axial type permanent magnet motor of this embodiment, and the contour line of the coil of a stator. It is the comparison figure which compared the relationship between the rotation of a rotor and the number of magnetic flux linkages in an axial type permanent magnet motor with the conventional structure and this embodiment. In the axial type permanent magnet motor of this embodiment, it is explanatory drawing explaining the variation which sets so that the outline of a coil and the outline of a permanent magnet may be contacted / separated in a rotor rotation direction in a non-parallel state at the time of rotation of a rotor. is there. In the axial type permanent magnet motor of the present embodiment, the contour lines of the adjacent coils and the contour lines of the adjacent permanent magnets are arranged in parallel, and the contact lines of the respective contour lines when the coil width and the permanent magnet width are not matched. It is explanatory drawing explaining a separation state. It is explanatory drawing explaining the example which has arrange | positioned the magnetic body between the adjacent permanent magnets in the axial type permanent magnet motor of this embodiment. It is explanatory drawing of the slot width | variety and salient pole width | variety in the axial type permanent magnet motor of this embodiment. In the axial type permanent magnet motor of this embodiment, it is a figure which shows the relationship of cogging torque with respect to slot width / salient pole width. In the axial type permanent magnet motor of this embodiment, it is a figure which shows the relationship of the number of magnet linkages with respect to slot width / salient pole width. It is explanatory drawing of stator inclination | tilt (theta) and rotor inclination | tilt (alpha) in the axial type permanent magnet motor of this embodiment. In the axial type permanent magnet motor of this embodiment, it is a figure which shows the relationship between the number of magnet linkages and cogging torque with respect to (alpha) / (theta).

Explanation of symbols

  DESCRIPTION OF SYMBOLS 10 Axial type permanent magnet motor, 12 stator, 12a stator core, 14 rotor, 16 casing, 18 rotating shaft, 20 permanent magnet, 20a outline, 22 teeth, 24 coil, 24a outline, 26 Magnetic body.

Claims (9)

An axial type permanent magnet motor in which a magnetic pole formed by a coil mounted on a stator and a permanent magnet of a rotor are arranged to face each other with a predetermined interval in a direction parallel to a rotation axis,
The outline of the coil and magnet in the direction intersecting the rotor rotation direction is substantially linear, and the coil outline and the magnet outline are not parallel to each other in the rotor rotation direction when the rotor rotates. An axial type permanent magnet motor characterized by being set to The motor according to claim 1, wherein
By setting the contour lines of the magnets arranged adjacent to each other in the rotor to be non-parallel, the contour line of the coil and the contour line of the magnet are contacted and separated in the rotor rotation direction in a non-parallel state when the rotor rotates. Axial type permanent magnet motor characterized by the above. The motor according to claim 1 or 2,
By setting the contour lines of adjacent coils in the stator to be non-parallel to each other, the coil contour line and the magnet contour line are in contact with or separated from each other in the rotor rotation direction in a non-parallel state when the rotor rotates. Axial type permanent magnet motor characterized by the above. The motor according to claim 1, wherein
By making the width in the direction intersecting the rotor rotation direction of the magnet in the rotor and the width in the direction intersecting the rotor rotation direction of the coil in the stator inconsistent with each other, An axial permanent magnet motor characterized in that the contour lines are not parallel to each other and are contacted and separated in the rotor rotation direction. In the motor according to any one of claims 1 to 4,
The intersecting angle between the contour line in the direction intersecting the rotor rotation direction of the magnet in the rotor and the contour line in the direction intersecting the rotor rotation direction of the coil in the stator is the change in the output torque of the motor and the cogging torque. An axial permanent magnet motor characterized by being determined according to a balance with change. In the motor according to any one of claims 1 to 5,
An axial type permanent magnet motor, wherein a magnetic material is disposed between adjacent magnets in the rotor. The motor according to any one of claims 1 to 6,
The outline of the rotor magnet is substantially fan-shaped, and the gap between adjacent rotor magnets is rectangular.
The outline of the stator coil is substantially fan-shaped, and the gap between adjacent stator coils is rectangular.
A ratio of the circumferential gap between the rotor magnets to the circumferential gap between the stator coils is 2.4 to 3.2. The motor according to any one of claims 1 to 6,
The outline of the rotor magnet is substantially fan-shaped, and the gap between adjacent rotor magnets is rectangular.
The outline of the stator coil is substantially fan-shaped, and the gap between adjacent stator coils is rectangular.
The axial permanent magnet motor, wherein a ratio of a circumferential gap between the rotor magnets to a circumferential gap between the stator coils is 2.2 to 3.4. The motor according to any one of claims 1 to 6,
An outline α of the stator coil and the rotor magnet is substantially fan-shaped, and an angle α with respect to a straight line perpendicular to the radial direction of the rotor with respect to the outline intersecting the rotor rotation direction of the rotor magnet, and the rotor of the stator coil An axial permanent magnet having a ratio α / θ of an angle θ with respect to a straight line in the radial direction of the rotor with respect to a contour line in a direction intersecting the rotational direction within a range of 0.86 to 0.89 motor.

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