JP2019004606A - Method for manufacturing magnet material and method for manufacturing motor - Google Patents

Abstract

To easily form a magnet which is used for a motor.SOLUTION: An admixture 30 containing magnet powder 31 and a binder 32 is filled in a metal mold 42 of a magnetic field molding apparatus 40, and an orientation magnetic field is applied to the admixture 30 by orientation devices 43, 46 to orientate the magnetic powder 31. Then, an orientation sheet magnet 50 having flexibility is generated by the admixture 30. Thus, at a molding stage of the orientation sheet magnet 50 having flexibility, the orientation sheet magnet 50 is orientated. The orientation sheet magnet 50 is attached to an inner peripheral surface of a cylindrical yoke 11, and magnetization processing is performed to be made into a cylindrical magnet 12.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a magnet material manufacturing method and a motor manufacturing method.

  Conventionally, motors such as a brush motor and a brushless motor have a driving magnet. For example, a rotor (rotor) included in a motor is formed by magnetizing an anisotropic magnet after orientation treatment (see, for example, Patent Document 1).

JP-A-63-36508

  Incidentally, the stator included in the motor includes a cylindrical magnet attached to the inner peripheral surface of the yoke or the case housing. It may be difficult to apply a sufficient orientation magnetic field to such a cylindrical anisotropic magnet. For this reason, it is required to easily generate a magnet for use in a motor by applying a sufficient orientation magnetic field.

  The present invention has been made to solve the above problems, and an object of the present invention is to provide a magnet manufacturing method and a motor manufacturing method capable of easily forming a magnet for use in a motor.

  A method of manufacturing a magnet material that solves the above-described problem is a method of manufacturing a magnet included in a motor, in which a mixed material containing anisotropic magnet powder and a flexible binder is filled in a mold, and the mold is used. The method includes forming the mixed material into a sheet shape and applying a magnetic field to the mixed material in the mold to orient the anisotropic magnet powder to generate a flexible oriented sheet magnet.

  According to this configuration, since the anisotropic magnet powder is oriented at the stage of molding the sheet-like magnet, a sufficient orientation magnetic field can be applied compared to the case of orienting the annular magnet, and the highly oriented magnet Is obtained. And a magnet of a motor can be easily formed by attaching an orientation sheet magnet having flexibility to a peripheral surface of a member of a rotor or a stator, for example, a cylindrical yoke. Also, cylindrical magnets with various orientations such as radial orientation and polar orientation orientation are controlled by controlling the orientation magnetic field at the stage of molding a mixed material containing anisotropic magnet powder and flexible binder into a sheet shape. Is easily obtained.

  In the method for producing a magnet material, the step of generating the oriented sheet magnet by performing the step of generating the oriented sheet magnet multiple times by controlling the magnetic field to be applied, and the step of producing the oriented sheet magnet, It is preferable to have the process of producing | generating the several orientation sheet magnet from which the orientation of one orientation sheet magnet differs from the orientation of another orientation sheet magnet, and laminating | stacking these orientation sheet magnets.

  According to this configuration, a plurality of orientation sheet magnets having different orientation directions from each other are stacked and formed into a cylindrical shape, thereby obtaining magnets with various orientations that cannot be obtained with one orientation sheet magnet. It is done.

  In the above method for producing a magnet material, the anisotropic magnet powder is oriented to produce the oriented sheet magnet in which N poles and S poles are alternately arranged along one direction. It is preferable to cut along the arrangement direction of the magnetic poles to generate an oriented sheet magnet for one round of the circumferential surface of the rotor or stator member of the motor.

According to this configuration, in the cylindrical magnet obtained by attaching the oriented sheet magnet to the circumferential surface of the rotor or stator member, a cylindrical magnet having magnetic poles along the axial direction can be obtained.
In the above method for producing a magnet material, the anisotropic magnet powder is oriented to produce the oriented sheet magnet in which N poles and S poles are alternately arranged along one direction. It is preferable that an oriented sheet magnet for one round of the circumferential surface of the rotor or stator member of the motor is generated by cutting obliquely with respect to the arrangement direction of the magnetic poles.

  According to this configuration, in the cylindrical magnet obtained by attaching the oriented sheet magnet to the circumferential surface of the rotor or stator member, each magnet has a skew in which each magnetic pole is inclined in the circumferential direction with respect to the axial direction. Is easily obtained.

  A method of manufacturing a motor that solves the above problem is a method of manufacturing a motor having a cylindrical magnet, in which a mixed material containing anisotropic magnet powder and a flexible binder is filled in a mold, Forming the mixed material into a sheet and applying a magnetic field to the mixed material in the mold to orient the anisotropic magnet powder to produce a flexible oriented sheet magnet; and the orientation A step of attaching a sheet magnet to a peripheral surface of a rotor or stator member, and a step of magnetizing the oriented sheet magnet to form the cylindrical magnet.

  According to this configuration, since the anisotropic magnet powder is oriented at the stage of molding the sheet-like magnet, a sufficient orientation magnetic field can be applied compared to the case of orienting the annular magnet, and the highly oriented magnet Is obtained. And a magnet of a motor can be easily formed by attaching an orientation sheet magnet having flexibility to a peripheral surface of a member of a rotor or a stator, for example, a cylindrical yoke. Also, cylindrical magnets with various orientations such as radial orientation and polar orientation orientation are controlled by controlling the orientation magnetic field at the stage of molding a mixed material containing anisotropic magnet powder and flexible binder into a sheet shape. Is easily obtained.

  In the motor manufacturing method, the step of generating the orientation sheet magnet by controlling the magnetic field to be applied a plurality of times to generate a plurality of orientation sheet magnets, and the step of generating the orientation sheet magnet includes at least 1 A plurality of orientation sheet magnets, wherein the orientation sheet magnets have different orientations from the orientation of other orientation sheet magnets, and the plurality of orientation sheet magnets are laminated. It is preferable that the cylindrical magnet is obtained by attaching to the circumferential surface of a rotor or stator member and magnetizing the plurality of oriented sheet magnets.

  According to this configuration, a plurality of orientation sheet magnets having different orientation directions from each other are stacked and formed into a cylindrical shape, thereby including magnets of various orientations that cannot be obtained with one orientation sheet magnet. A motor is obtained.

  In the motor manufacturing method described above, the oriented sheet magnet is cut to generate an oriented sheet magnet for one round of the circumferential surface of the rotor or the stator member, and the oriented sheet magnet for the one round is used as the member. It is preferable that the cylindrical magnet is made by attaching the oriented sheet magnet for one round to the circumferential surface.

  According to this configuration, a cylindrical magnet obtained by attaching the oriented sheet magnet to the circumferential surface of the rotor or stator member can be easily obtained.

  According to the method for manufacturing a magnet material and the method for manufacturing a motor of the present invention, a magnet used for a motor can be easily formed.

BRIEF DESCRIPTION OF THE DRAWINGS Schematic explanatory drawing of the motor of 1st Embodiment. (A)-(d) is a schematic explanatory drawing of the manufacturing process of the stator using the oriented sheet magnet and the oriented sheet magnet. (A)-(c) is explanatory drawing which shows the orientation state of an orientation sheet magnet. (A) is explanatory drawing of the oriented sheet magnet to cut, (b) is explanatory drawing of the oriented sheet magnet after cutting, (c) is explanatory drawing of a cylindrical magnet. (A) is explanatory drawing of the oriented sheet magnet to cut, (b) is explanatory drawing of the oriented sheet magnet after cutting, (c) is explanatory drawing of a cylindrical magnet. (A) is schematic explanatory drawing of the motor of 2nd Embodiment, (b) is explanatory drawing which expand | deploys and shows the cylindrical magnet of 2nd Embodiment. (A) is explanatory drawing of the orientation sheet magnet to laminate | stack, (b) is explanatory drawing of the orientation sheet magnet laminated | stacked. Explanatory drawing which shows the polar anisotropic orientation with respect to a cylindrical magnet. (A) (b) is explanatory drawing which shows the polar anisotropic orientation with respect to a cylindrical magnet.

Hereinafter, each embodiment will be described.
In the accompanying drawings, components may be shown in an enlarged manner for easy understanding. The dimensional ratios of the components may be different from the actual ones or in other drawings. Further, in the cross-sectional view, some components may not be hatched for easy understanding.

(First embodiment)
Hereinafter, the first embodiment will be described.
As shown in FIG. 1, the motor 1 of this embodiment includes a stator 10 and a rotor 20. The stator 10 includes a cylindrical yoke 11 and a cylindrical magnet 12 attached to the inner peripheral surface of the yoke 11. In FIG. 1, the cylindrical magnet 12 is radially oriented and magnetized so that N poles and S poles are alternately arranged in the circumferential direction on the inner peripheral surface. The cylindrical magnet 12 is composed of an oriented sheet magnet as a flexible magnet material. The oriented sheet magnet has flexibility and is formed in a substantially flat plate shape. The oriented sheet magnet has a desired orientation in a substantially flat state. This oriented sheet magnet is disposed along the inner peripheral surface 11 a of the yoke 11. Thereafter, a magnetizing process is performed to form a cylindrical magnet 12.

The manufacturing process of this orientation sheet magnet and the manufacturing process of the cylindrical magnet 12 using the orientation sheet magnet are demonstrated.
As shown in FIG. 2A, a mixed material 30 including magnet powder 31 and a binder 32 is generated. The magnet powder 31 is, for example, anisotropic magnet powder. As anisotropic magnet powder, neodymium (Nd-Fe-B) magnet, ferrite magnet, samarium iron nitrogen (Sm-Fe-N) magnet, samarium cobalt (Sm-Co) magnet, etc. . The binder 32 is a flexible binding material, and for example, rubber or the like can be used. In FIG. 2A, a liquid binder is shown as the binder 32, but a solid binder can also be used. Note that an additive 33 may be added to the mixed material 30. The additive 33 is, for example, a coupling material, a lubricant, or the like.

  As shown in FIG. 2B, the mixed material 30 is stored in the tank 41 of the magnetic field forming device 40. Then, the mixed material 30 is filled from the tank 41 into the mold 42. In the tank 41, the magnet powder 31 contained in the mixed material 30 is uniformly dispersed. In addition, in FIG.2 (b), the arrow shown to each magnet powder 31 shows the orientation direction of each magnet powder 31. FIG.

  The mold 42 is for molding the mixed material 30 into a sheet shape. The mold 42 is a non-magnetic material that passes a magnetic field. Orientation devices 43 and 46 are provided above and below the mold 42. The orientation devices 43 and 46 apply a magnetic field to the mixed material 30 in the mold 42. In the present embodiment, the orientation device 43 includes a core 44 and coils 45 a and 45 b wound around the core 44. The orientation device 43 is disposed with the magnetic poles 44 a and 44 b of the core 44 facing the mold 42. Similarly, the orientation device 46 includes a core 47 and coils 48 a and 48 b wound around the core 47. The orientation device 46 is disposed with the magnetic poles 47 a and 47 b of the core 47 facing the mold 42.

  The orientation devices 43 and 46 generate a magnetic field according to the direction of the applied current of the coils 45a, 45b, 48a, and 48b, the magnitude of the applied current, and the like. By this magnetic field, the magnet powder 31 contained in the mixed material 30 in the mold 42 is oriented. The position of the magnetic poles 44a, 44b, 47a, 47b of the cores 44, 47 around which the coils 45a, 45b, 48a, 48b are wound, the direction of the applied current of the coils 45a, 45b, 48a, 48b, and the magnitude of the applied current are appropriately determined. By setting, the orientation of the magnet powder 31 contained in the mixed material 30 can be controlled. In FIG.2 (b), the orientation apparatus 43 is controlled and the magnetic powder 31 of the mixed material 30 is in the anisotropic orientation (the orientation in which the magnetic pole is generated on one surface and the magnetic pole is not generated on the other surface). It is shown. Note that the entrance of the mold 42 may be a ferromagnetic material to control the magnetic flux.

  Further, the magnetic field shaping device 40 includes a processing machine 49. The processor 49 applies energy necessary for solidification of the mixed material 30 (for example, crosslinking of the binder 32) to the mixed material 30. As energy, high frequency, electron beam, heat, etc. can be used. With this magnetic field shaping device 40, an oriented sheet magnet 50 shown in FIG.

  The oriented sheet magnet 50 shown in FIG. 2C has a rectangular plate shape, and for example, N poles and S poles are alternately oriented along the long side on the upper surface. In the magnetic pole arrangement direction, the sizes (magnetic pole widths) of the N pole and the S pole are set by the positions (intervals) of the magnetic poles 44a, 44b, 47a, 47b of the orientation devices 43, 46. That is, by setting the number (pole number) and interval (pole pitch) of the magnetic poles 44a, 44b, 47a, 47b of the orientation devices 43, 46, the oriented sheet magnet 50 having an arbitrary magnetic pole width can be obtained. Further, by setting the direction and magnitude of the applied current of the coils 45a, 45b, 48a, 48b of the orientation device 43 shown in FIG. 2B, the orientation sheet magnet 50 having an arbitrary orientation can be obtained.

  2B schematically shows an apparatus for applying an orientation magnetic field to the mixed material 30 in the mold 42, that is, the orientation sheet magnet 50 molded by the mold 42. The shape, the number of magnetic poles, etc. are not limited to this. In addition, at least one of the orientation devices 43 and 46 may be embedded in the mold 42. Further, permanent magnets can be used as the orientation devices 43 and 46. As the permanent magnet, for example, a sintered magnet (for example, a rare earth sintered magnet) can be used.

  As shown in FIG. 2 (d), the oriented sheet magnet 50 is attached to the inner peripheral surface of the yoke 11. Then, the orientation sheet magnet 50 is magnetized by a magnetizing device (not shown). Thereby, the desired cylindrical magnet 12 is obtained.

  Fig.3 (a)-FIG.3 (c) show the example of orientation in an orientation sheet magnet. The orientation of the oriented sheet magnet 51 shown in FIG. 3A is a radial orientation in which magnetic poles appear on both main surfaces and oriented in the thickness direction.

The orientation of the oriented sheet magnet 52 shown in FIG. 3B is a polar anisotropic orientation in which the magnetic pole appears only on one main surface (the upper surface in FIG. 3B).
The orientation of the orientation sheet magnet 53 shown in FIG. 3C is a Halbach orientation that includes magnetic poles appearing on both principal surfaces and including an orientation along the principal surface between the magnetic poles.

  In the case of the radially oriented oriented sheet magnet 51 shown in FIG. 3A, the oriented sheet magnet 51 is moved to the yoke with the upper surface or the lower surface of the oriented sheet magnet 51 facing the inner peripheral surface of the yoke 11 shown in FIG. 11 is attached to the inner peripheral surface. Thereby, the stator 10 (refer FIG. 1) which has the cylindrical magnet 12 and the yoke 11 by the orientation sheet magnet 51 is obtained.

  In the case of the orientation sheet magnet 52 having the anisotropic orientation shown in FIG. 3B, the orientation sheet magnet 52 is placed on the yoke with the lower surface of the orientation sheet magnet 52 facing the inner peripheral surface of the yoke 11 shown in FIG. 11 is attached to the inner peripheral surface. Note that in the case of the polar anisotropic oriented sheet magnet 52, the member to be attached may be a non-magnetic material. For example, the stator can be obtained by attaching the oriented sheet magnet 52 to the inner peripheral surface of the nonmagnetic case housing.

  In the case of the orientation sheet magnet 53 of Halbach orientation shown in FIG. 3C, the orientation sheet magnet 53 is moved to the yoke with the upper surface or the lower surface of the orientation sheet magnet 53 facing the inner peripheral surface of the yoke 11 shown in FIG. 11 is attached to the inner peripheral surface. When the orientation sheet magnet 53 of Halbach orientation is used, the magnetic flux density distribution in the circumferential direction of the stator can be made substantially sinusoidal.

The oriented sheet magnet 50 (51-53) is preferably cut according to the size of the member to be attached.
As shown in FIG. 4A, the oriented sheet magnet 51 is cut along the arrangement direction of the magnetic poles (N pole, S pole) (direction indicated by the two-dot chain line), and shown in FIG. 4B. A rectangular oriented sheet magnet 51a is obtained. The longitudinal direction (the left-right direction in FIG. 4B) of the orientation sheet magnet 51a is the circumferential direction, and the direction orthogonal to the circumferential direction (the up-down direction in FIG. 4B) is the width direction. The length in the circumferential direction is one round of the inner circumferential surface of the yoke 11 shown in FIG. As shown in FIG. 4C, the oriented sheet magnet 51a is a rounded cylindrical magnet. Thereby, the orientation sheet magnet 51a is attached to the inner peripheral surface of the yoke 11 shown in FIG.

  As shown in FIG. 5 (a), the orientation sheet magnet 50 is cut in a direction (indicated by a two-dot chain line) inclined with respect to the arrangement direction of the magnetic poles (N pole, S pole). The parallelogram-shaped oriented sheet magnet 51b shown in FIG. The length of the side of the oriented sheet magnet 51b (the length of the side in the left-right direction in FIG. 5B) is one round of the inner peripheral surface of the yoke 11 shown in FIG. As shown in FIG. 5C, the oriented sheet magnet 51b is a rounded cylindrical magnet.

  Thereby, the orientation sheet magnet 51b is attached to the inner peripheral surface of the yoke 11 shown in FIG. The cylindrical magnet (orientation sheet magnet 51b) is skewed with an inclination in the circumferential direction with respect to the axial direction (width direction in FIG. 5B). And in the motor which has this cylindrical magnet 12, the change of the magnetic flux at the time of pole switching becomes smooth by the skew of a magnetic pole (N pole, S pole). Therefore, an increase in cogging torque in the motor can be suppressed.

  In addition, in FIG.5 (b), the parallelogram-shaped orientation sheet magnet 51b was produced | generated, However, The shape of the orientation sheet magnet obtained by a cutting process is good also as a rectangular shape. Even in this case, on the main surface of the orientation sheet magnet, the orientation sheet magnet is rounded so that the direction perpendicular to the cut side is the axial direction, thereby generating a cylindrical magnet. Even in the cylindrical magnet thus generated, a skew-oriented cylindrical magnet having an inclination in the circumferential direction with respect to the axial direction can be obtained. And in the motor which has this cylindrical magnet, the change of the magnetic flux at the time of pole switching becomes smooth by skew orientation. For this reason, an increase in cogging torque in the motor can be suppressed.

  Note that when the oriented sheet magnet 50 is cut, the oriented sheet magnet 50 is preferably demagnetized. By the demagnetization process, it is possible to suppress attachment of tools, chips, and the like that cut the oriented sheet magnet 51 to the oriented sheet magnet 51. Then, the oriented sheet magnets 51a and 51b after cutting (see FIGS. 4B and 5B) are attached to the inner peripheral surface of the yoke 11 shown in FIG. Then, the orientation sheet magnets 51 a and 51 b are magnetized by a magnetizing device (not shown) to form the cylindrical magnet 12. And after this, the cylindrical magnet 12 can be obtained more easily than in the case where the cylindrical magnet material is magnetized after the orientation treatment.

  4 (a) to 4 (b) and FIGS. 5 (a) to 5 (c) show examples in which the radially oriented oriented sheet magnet 51 is cut. The polar anisotropic orientation sheet magnet 52 shown in FIG. 3B and the Halbach orientation orientation sheet magnet 53 shown in FIG. 3C can be similarly cut.

(Function)
First, an alignment method of a comparative example will be described. Here, a case where a polar anisotropic cylindrical magnet is obtained will be described.

  FIG. 8 shows a case where the magnetic poles are oriented in the polar anisotropic orientation (outer peripheral polar anisotropic orientation) in which the magnetic pole appears only on the outer peripheral surface of the annular magnet 61. The orientation device 71 includes a plurality of cores 71a disposed on the outer side in the radial direction of the annular magnet 61, and coils 71b wound around the cores 71a. An orientation magnetic field 71c is generated by current supplied to the plurality of cores 71a, and the annular magnet 61 is oriented.

  FIG. 9A and FIG. 9B show a case where the magnetic poles are oriented in the polar anisotropic orientation (inner circumferential polar anisotropic orientation) in which the magnetic pole appears only on the inner peripheral surface of the annular magnet 62. The orientation device 72 shown in FIG. 9A includes a core 72a disposed inside the annular magnet 62 and a plurality of coils 72b wound around the core 72a. A current is supplied to each coil 72b, and the annular magnet 62 is oriented by the generated orientation magnetic field 72c. The orientation device 73 shown in FIG. 9B orients the annular magnet 62 with a permanent magnet.

  As shown in FIGS. 9A and 9B, when the inner circumferential pole is anisotropically oriented, it is necessary to arrange the orientation devices 72 and 73 inside the annular magnet 62. However, when orienting the annular magnet 62 having a small inner diameter, the orientation devices 72 and 73 become small and a sufficient orientation magnetic field cannot be applied to the annular magnet 62.

  In the case of this embodiment, as described above, the orientation sheet magnet 50 (51-53) is oriented in the molding stage of the flexible orientation sheet magnet 50 (51-53). For this reason, a sufficient orientation magnetic field can be applied to the orientation sheet magnet 50 (51 to 53). And by using the oriented sheet magnet 50 (51-53) oriented in this way, for example, a magnet with an anisotropic orientation on the inner circumference can be easily formed. Similarly, when the oriented sheet magnet 51 is cut to obtain the oriented sheet magnets 51a and 51b, a sufficient orientation magnetic field can be applied by orienting at the stage of the flat plate shape after the cutting process.

  Moreover, in the alignment method of the above-described comparative example, different alignment devices 71 to 73 are required for the outer peripheral polar anisotropic alignment and the inner peripheral polar anisotropic alignment. On the other hand, in this embodiment, the orientation sheet magnet 50 is oriented in the molding stage of the orientation sheet magnet 50 having flexibility. For example, by using the oriented sheet magnet 52 that is polar-oriented, and forming the oriented sheet magnet 52 so that the magnetic poles are on the inner circumference side, a cylindrical magnet having the inner-polar orientation is obtained. Further, by forming the oriented sheet magnet 52 so that the magnetic poles are on the outer peripheral side, a cylindrical magnet with an outer peripheral polar anisotropic orientation can be obtained. That is, the flexible orientation sheet magnet 52 makes it possible to obtain an inner circumferentially anisotropic cylindrical magnet and an outer circumferentially anisotropic cylindrical magnet.

  In addition, the magnet of an outer periphery polar anisotropic orientation can be used for a rotor. For example, the oriented sheet magnet 50 (51-53) is attached to the outer peripheral surface of the member (for example, rotor core) included in the rotor. For example, when using the polar anisotropic orientation sheet magnet 52 shown in FIG. 3B, a non-magnetic material can be used for a member (for example, a rotor core) included in the rotor. In FIG.3 (b), the lower surface of the orientation sheet magnet 52 is turned to the outer peripheral surface of the member of a rotor, and the orientation sheet magnet 52 is attached to the member.

As described above, according to the present embodiment, the following effects can be obtained.
(1-1) The mixed material 30 including the magnet powder 31 and the binder 32 is filled in the mold 42 of the magnetic field forming device 40, and an orientation magnetic field is applied to the mixed material 30 by the aligning devices 43 and 46, so Orient. And the orientation sheet magnet 50 which has flexibility with the mixed material 30 is produced | generated. Thus, the orientation sheet magnet 50 (51-53) is orientated in the shaping | molding step of the orientation sheet magnet 50 (51-53) which has flexibility. For this reason, a sufficient orientation magnetic field can be applied to the orientation sheet magnet 50 (51 to 53).

  (1-2) By using the oriented sheet magnet 50 (51-53) that has been oriented, for example, an inner circumferentially anisotropic magnet can be easily formed. Similarly, when the oriented sheet magnet 51 is cut to obtain the oriented sheet magnets 51a and 51b, a sufficient orientation magnetic field can be applied by orienting at the stage of the flat plate shape after the cutting process.

  (1-3) In the forming stage of the flexible oriented sheet magnet 50, the oriented sheet magnet 50 is oriented. For example, by using the oriented sheet magnet 52 that is polar-oriented, and forming the oriented sheet magnet 52 so that the magnetic poles are on the inner circumference side, a cylindrical magnet having the inner-polar orientation is obtained. Further, by forming the oriented sheet magnet 52 so that the magnetic poles are on the outer peripheral side, a cylindrical magnet with an outer peripheral polar anisotropic orientation can be obtained. That is, the flexible orientation sheet magnet 52 provides a cylindrical magnet with an inner peripheral polar anisotropic orientation and a cylindrical magnet with an outer peripheral polar anisotropic orientation.

  (1-4) The oriented sheet magnet 51 is cut along the arrangement direction of the magnetic poles (N pole, S pole) to obtain a rectangular oriented sheet magnet 51a. The longitudinal direction of the orientation sheet magnet 51 a is the circumferential direction, and the length in the circumferential direction is one round of the inner circumferential surface of the yoke 11. Thereby, the orientation sheet magnet 51a can be attached to the inner peripheral surface of the yoke 11 without excess or deficiency.

  (1-5) The oriented sheet magnet 51 is cut in a direction inclined with respect to the arrangement direction of the magnetic poles (N pole, S pole) to obtain a parallelogram shaped oriented sheet magnet 51b. The length of the side of the oriented sheet magnet 51 b is one round of the inner peripheral surface of the yoke 11. Thereby, the cylindrical magnet (orientation sheet magnet 51b) attached to the inner peripheral surface of the yoke 11 is skewed in the circumferential direction with respect to the axial direction. And in the motor which has this cylindrical magnet 12, the change of the magnetic flux at the time of pole switching becomes smooth by the skew of a magnetic pole (N pole, S pole). Therefore, an increase in cogging torque in the motor can be suppressed.

(Second Embodiment)
The second embodiment will be described below.
In addition, in this embodiment, the same code | symbol is attached | subjected about the same structural member as the said embodiment, and the description is abbreviate | omitted.

  As shown in FIG. 6A, the motor 101 of this embodiment has a stator 110 and a rotor 20. The stator 110 includes a cylindrical yoke 11 and a cylindrical magnet 120 attached to the inner peripheral surface of the yoke 11. In FIG. 6A, the cylindrical magnet 120 is composed of a plurality (three in the present embodiment) of oriented sheet magnets 121, 122, 123 that are stacked in the radial direction. FIG. 6B shows a state in which the cylindrical magnet 120 is expanded, and shows the orientation state of each orientation sheet magnet 121, 122, 123.

In FIG. 6A, the first oriented sheet magnet 121, the second oriented sheet magnet 122, and the third oriented sheet magnet 123 are sequentially formed from the inside toward the outside.
As shown in FIG. 7A, the first oriented sheet magnet 121 is radially oriented. In other words, the first oriented sheet magnet 121 is oriented such that magnetic poles appear on the inner peripheral surface and the outer peripheral surface, and N poles and S poles are alternately arranged in the circumferential direction on the inner peripheral surface. Similar to the first orientation sheet magnet 121, the second orientation sheet magnet 122 is radially oriented. The third oriented sheet magnet 123 is polar-oriented. That is, the third oriented sheet magnet 123 is oriented such that magnetic poles appear on the inner peripheral surface, and N poles and S poles are alternately arranged in the circumferential direction on the inner peripheral surface. In the first to third oriented sheet magnets 121 to 123, the arrangement pitch of the magnetic poles is equal to each other. Therefore, as shown in FIG. 7B, the cylindrical magnet 120 obtained by laminating the first to third oriented sheet magnets 121 to 123 has a magnetic pole appearing on the inner peripheral surface, and a long magnetic path (high permeance). This is a cylindrical magnet having an anisotropic orientation. Thus, by laminating a plurality of oriented sheet magnets, a long magnetic path (high permeance) can be achieved.

  In addition, you may shape | mold the orientation sheet magnet obtained by laminating | stacking the 1st-3rd orientation sheet magnet 121-123 so that the 1st orientation sheet magnet 121 may be made into the outer peripheral side. In this case, a magnetic pole appears on the outer peripheral surface, and a cylindrical magnet having a long magnetic path (high permeance) and anisotropic orientation is obtained.

  Moreover, you may cut | disconnect each orientation sheet magnet 121-123 similarly to above-mentioned FIG. 4 (a) and FIG.4 (b) or FIG.5 (a) and FIG.5 (b). For example, you may cut | disconnect the orientation sheet magnet (refer FIG.7 (b)) obtained by laminating | stacking the 1st-3rd orientation sheet magnet 121-123. Moreover, each orientation sheet magnet 121-123 may be cut individually, and the orientation sheet magnet after a process may be laminated | stacked.

  A cylindrical magnet skewed by a long magnetic path (high permeance) is obtained by cutting in the same manner as in FIGS. 5 (a) and 5 (b). A motor using this magnet has a high magnetic flux and can suppress an increase in cogging torque.

  When the orientation sheet magnets 121 to 123 are cut, the orientation sheet magnets 121 to 123 are preferably demagnetized. By demagnetizing treatment, it is possible to suppress the tools, chips, and the like that cut the oriented sheet magnets 121 to 123 from adhering to the oriented sheet magnets 121 to 123. Then, the oriented sheet magnets 121 to 123 after cutting are attached to the inner peripheral surface of the yoke 11 shown in FIG. And the orientation sheet magnets 121-123 are magnetized using the magnetizing apparatus which is not illustrated. Thereby, the cylindrical magnet 120 is easily obtained compared with the case where the cylindrical magnet material is magnetized after the orientation treatment.

As described above, according to the present embodiment, the following effects can be obtained.
(2-1) A plurality of oriented sheet magnets 121 to 123 oriented in a desired orientation are generated. The orientation sheet magnets 121 to 123 are obtained by controlling the magnetic field to be applied in the magnetic field forming apparatus 40. These oriented sheet magnets 121 to 123 are laminated, and the laminated oriented sheet magnets 121 to 123 are attached to the inner peripheral surface of the yoke 11 to form a cylindrical magnet 120. Thereby, the cylindrical magnet 120 of various orientations which cannot be obtained with one oriented sheet magnet is obtained.

  (2-2) The radially oriented oriented sheet magnets 121 and 122 and the polar anisotropic oriented oriented sheet magnet 123 were laminated to form a cylindrical magnet 120. The cylindrical magnet 120 is a cylindrical magnet having magnetic poles appearing on the inner peripheral surface and having a long magnetic path (high permeance) and an anisotropic orientation. Thus, by laminating a plurality of oriented sheet magnets, a long magnetic path (high permeance) can be achieved.

  (2-3) The oriented sheet magnets 121 to 123 are cut obliquely with respect to the magnetic pole arrangement direction, and the processed oriented sheet magnet is attached to the inner peripheral surface of the yoke 11. Thereby, the cylindrical magnet skewed by the long magnetic path (high permeance) is obtained. A motor using this magnet has a high magnetic flux and can suppress an increase in cogging torque.

(Modification)
In addition, you may implement each said embodiment in the following aspects.
-You may comprise the rotor which has a magnet with respect to said each embodiment. For example, the oriented sheet magnet 50 (51-53) is attached to the outer peripheral surface of the member (for example, rotor core) included in the rotor. For example, when using the polar anisotropic orientation sheet magnet 52 shown in FIG. 3B, a non-magnetic material can be used for a member (for example, a rotor core) included in the rotor. In FIG.3 (b), the lower surface of the orientation sheet magnet 52 is turned to the outer peripheral surface of the member of a rotor, and the orientation sheet magnet 52 is attached to the member. Similarly, as in the second embodiment, a rotor having a plurality of stacked oriented sheet magnets may be used.

  -In the said 2nd Embodiment, the orientation sheet magnet 121,122 of radial orientation and the orientation sheet magnet 123 of polar anisotropic orientation were laminated | stacked, and it was set as the one orientation sheet magnet. On the other hand, the orientation sheet magnet 53 of Halbach orientation shown in FIG. 3C may be laminated in combination with another orientation sheet magnet. Thus, by laminating oriented sheet magnets having different orientations, a magnet having a complicated orientation that cannot be obtained with a single oriented sheet magnet can be obtained.

  In the second embodiment, the three oriented sheet magnets 121 to 123 are laminated, but two or four or more oriented sheet magnets may be laminated.

DESCRIPTION OF SYMBOLS 10,110 ... Stator, 11 ... Yoke, 12, 120 ... Cylindrical magnet, 20 ... Rotor, 31 ... Magnet powder, 32 ... Binder, 40 ... Magnetic field shaping | molding apparatus, 42 ... Mold, 43, 46 ... Orientation apparatus, 50 , 51-53, 121-123 ... oriented sheet magnets.

Claims (7)

A method of manufacturing a magnet material included in a motor,
A mixed material containing anisotropic magnet powder and a flexible binder is filled in a mold, the mixed material is molded into a sheet shape by the mold, and a magnetic field is applied to the mixed material in the mold. The manufacturing method of a magnet material which has the process of orientating the said anisotropic magnet powder and producing | generating the oriented sheet magnet which has flexibility. A plurality of orientation sheet magnets are generated by performing a step of generating the orientation sheet magnet a plurality of times by controlling a magnetic field to be applied,
In the step of generating the orientation sheet magnet, the orientation of at least one orientation sheet magnet generates a plurality of orientation sheet magnets different from the orientation of other orientation sheet magnets,
Having a step of laminating the plurality of oriented sheet magnets;
The method for producing a magnet material according to claim 1. The anisotropic magnet powder is oriented to produce the oriented sheet magnet in which N poles and S poles are alternately arranged along one direction,
Cutting the oriented sheet magnet along the arrangement direction of the magnetic poles to generate an oriented sheet magnet for one round of the circumferential surface of the rotor or stator member of the motor;
The manufacturing method of the magnet material of Claim 1 or 2 characterized by these. The anisotropic magnet powder is oriented to produce the oriented sheet magnet in which N poles and S poles are alternately arranged along one direction,
Cutting the orientation sheet magnet obliquely with respect to the arrangement direction of the magnetic poles to generate an orientation sheet magnet for one turn of the peripheral surface of the rotor or stator member of the motor;
The manufacturing method of the magnet material of Claim 1 or 2 characterized by these. A method of manufacturing a motor having a cylindrical magnet,
A mixed material containing anisotropic magnet powder and a flexible binder is filled in a mold, the mixed material is molded into a sheet shape by the mold, and a magnetic field is applied to the mixed material in the mold. Producing an oriented sheet magnet having flexibility by orienting the anisotropic magnet powder;
Attaching the oriented sheet magnet to the circumferential surface of a rotor or stator member;
A step of magnetizing the oriented sheet magnet to form the cylindrical magnet;
The manufacturing method of the motor which has this. A plurality of orientation sheet magnets are generated by performing a step of generating the orientation sheet magnet a plurality of times by controlling a magnetic field to be applied,
In the step of generating the orientation sheet magnet, the orientation of at least one orientation sheet magnet generates a plurality of orientation sheet magnets different from the orientation of other orientation sheet magnets,
Laminating the plurality of oriented sheet magnets,
Attaching the plurality of laminated orientation sheet magnets to a peripheral surface of a rotor or stator member, and magnetizing the orientation sheet magnets to form the cylindrical magnet;
The method of manufacturing a motor according to claim 5. Cutting the orientation sheet magnet to produce an orientation sheet magnet for one circumference of the rotor or stator member; attaching the one orientation sheet magnet to the circumference of the member; The method of manufacturing a motor according to claim 5, wherein the one-round oriented sheet magnet is magnetized to form the cylindrical magnet.