ROTOR, METHOD OF PRODUCING THE ROTOR, AND MOTOR

Abstract

A plurality of plate-like magnets are partially bonded at a predetermined interval to an inner circumferential surface of a rotor yoke with a first adhesive via a positioning member for positioning in a radial direction and in an axial direction, and a second adhesive is heat-cured in a state where the positioning member is removed, thus bonding and fixing the plurality of plate-like magnets at a predetermined interval and spaced apart from each other in a circumferential direction.

Claims

1. A rotor comprising a plurality of plate-like magnets divided in a circumferential direction at a predetermined interval at a circumferential surface of a rotor yoke, wherein the plate-like magnet is a flat plate-like magnet, and a first bonding part coated with a first adhesive curing in a predetermined time and a second bonding part coated with a thermosetting second adhesive taking a longer curing time than the first adhesive but having a higher bonding strength are formed next to each other or partially overlapping each other at a bonding surface of the magnet, using a plurality of adhesives having different curing conditions, and an adhesive layer is formed, using a void formed between a curved surface of the rotor yoke and a flat surface of the plate-like magnet as an adhesive reservoir of the first adhesive and the second adhesive, and the plurality of plate-like magnets are positioned in a radial direction and in an axial direction at the circumferential surface of the rotor yoke and partially bonded to the first bonding part by the curing of the first adhesive, and the plurality of plate-like magnets are bonded and fixed to each other via a predetermined gap in the circumferential direction at all of the first bonding part and the second bonding part by the thermosetting of the second adhesive.

2. The rotor according to claim 1, wherein the plate-like magnet is a rare earth magnet with a rust-proofed surface, and the first adhesive and the second adhesive are provided in a gap between the rotor yoke and the plate-like magnet.

3. The rotor according to claim 1, wherein with respect to an area of the first bonding part coated with the first adhesive and the second bonding part coated with the second adhesive at the bonding surface of the plate-like magnet, the second bonding part has an area equivalent to or greater than the area of the first bonding part.

4. The rotor according to claim 1, wherein at least one of an ultraviolet-curing or anaerobic-curing adhesive and a quick-setting adhesive is used as the first adhesive.

5. (canceled)

6. The rotor according to claim 1, wherein the rotor is a rotor of an outer-rotor motor in which the plurality of plate-like magnets divided in a circumferential direction are fixed at a predetermined interval to an inner circumferential surface of the rotor yoke formed in a cup-like shape.

7. The rotor according to claim 1, wherein the rotor is a rotor of an inner-rotor motor in which the plurality of plate-like magnets divided in a circumferential direction are fixed at a predetermined interval to an outer circumferential surface of the rotor yoke formed in a columnar shape.

8. A motor comprising the rotor according to claim 1 and a stator having a stator pole tooth opposite the plate-like magnet of the rotor.

9. A method of producing a rotor, comprising: a step of coating a bonding surface of each of a plurality of divided flat plate-shaped plate-like magnets with a first adhesive curing in a predetermined time, using a void formed between a curved surface of a rotor yoke and a flat surface of the plate-like magnet as an adhesive reservoir; a step of coating the bonding surface of each of the plate-like magnets with a thermosetting second adhesive taking a longer curing time than the first adhesive but having a higher bonding strength, using the void formed between the curved surface of the rotor yoke and the flat surface of the plate-like magnet as the adhesive reservoir; a step of attaching a positioning member having pectinate partition members coupled in an annular form for positioning the plate-like magnets in a radial direction and an axial direction, to a circumferential surface of the rotor yoke; a step of positioning the plate-like magnets between the partition members of the rotor yoke with the positioning member attached, and arranging the plate-like magnets at a predetermined interval at the circumferential surface of the rotor yoke via the first adhesive and the second adhesive; a step of curing the first adhesive coating the plate-like magnets, and thus positioning the plate-like magnets in the radial direction and the axial direction and partially bonding the plate-like magnets to the rotor yoke at a first bonding part; a step of extracting the positioning member from the rotor yoke; and a step of thermosetting the second adhesive and thus bonding and fixing the plate-like magnets to the rotor yoke at all of the first bonding part and a second bonding part.

10. The method of producing the rotor of an outer-rotor motor according to claim 9, comprising: a step of attaching a positioning member having pectinate partition members coupled to an annular coupling part for positioning the plate-like magnets in the radial direction and the axial direction, to an inner circumferential surface of a cylindrical rotor yoke; a step of inserting each of the plurality of the plate-like magnets between the partition members and positioning and arranging the plate-like magnets at a predetermined interval at the inner circumferential surface of the rotor yoke via the first adhesive and the second adhesive; and a step of assembling a rotor hub and a rotor shaft to the rotor yoke in a unified manner

11. The method of producing the rotor of an inner-rotor motor according to claim 9, comprising: a step of attaching a positioning member having pectinate partition members coupled to an annular coupling part for positioning the plate-like magnets in the radial direction and the axial direction, to an outer circumferential surface of a rotor yoke having a rotor shaft at its center; and a step of inserting each of the plurality of the plate-like magnets between the partition members and positioning and arranging the plate-like magnets at a predetermined interval at the outer circumferential surface of the rotor yoke via the first adhesive and the second adhesive.

12. The method of producing the rotor according to claim 9, wherein the plate-like magnets are partially bonded to the rotor yoke, using at least one of an ultraviolet-curing or anaerobic-curing adhesive and a quick-setting adhesive as the first adhesive.

13. The method of producing the rotor according to claim 9, wherein the plurality of plate-like magnets are magnetized before being bonded inside the rotor yoke or are magnetized after being bonded inside the rotor yoke.

Description

BRIEF DESCRIPTION OF DRAWINGS

[0041] FIGS. 1A to 1E are explanatory views showing a process of producing a rotor of an outer-rotor motor.

[0042] FIGS. 2A to 2D are explanatory views showing the process of producing the outer-rotor motor, continued from FIGS. 1A to 1E.

[0043] FIGS. 3A1 to 3B3 are explanatory views showing forms of plate-like magnets bonded and fixed to a rotor yoke.

[0044] FIGS. 4A to 4C are explanatory views showing a process of producing a rotor of an inner-rotor motor.

[0045] FIGS. 5A and 5B are explanatory views showing a bonding area of a first bonding part and a second bonding part of a plate-like magnet.

[0046] FIGS. 6A to 6D are process charts showing a method of producing a rotor of an outer-rotor motor according to the related art.

[0047] FIGS. 7A and 7B are process charts showing a method of producing a rotor of an inner-rotor motor according to the related art.

[0048] FIGS. 8A and 8B are explanatory views showing a required configuration of a rotor yoke and a rotor hub.

DESCRIPTION OF EMBODIMENTS

[0049] An embodiment of a rotor, a method of producing the rotor, and a motor according to the present invention will now be described with reference to the accompanying drawings. First, a schematic configuration of the motor is described with reference to FIGS. 1A to 1E. In this embodiment, a brushless DC motor of an outer-rotor type, or an inner-rotor type, described later, is used as an example of the motor.

[0050] As shown in FIGS. 2C and 2D, an outer-rotor motor M having a rotor 1 and a stator 2 is used as the brushless DC motor. A rotor hub 4 linked to a rotor shaft 3 is fitted in to close an opening at one end of a cylindrical rotor yoke 5 (magnetic material such as iron or stainless steel), thus forming the rotor 1 in a cup-like shape. To an inner circumferential surface 5a of the rotor yoke 5 (see FIG. 2A), a plurality of divided plate-like magnets 6 (rotor magnets) magnetized to alternately have an N pole and an S pole in the circumferential direction are bonded and fixed (see FIG. 2B). Each plate-like magnet 6 is arranged opposite a stator pole tooth 7b of a stator core 7, described later. The plate-like magnet 6, as a term, is not limited to a flat plate shape (see FIG. 3B1) but includes various forms such as a curved plate (see FIG. 3A1), provided that it is a magnetic plate member having a predetermined thickness.

[0051] As shown in FIG. 2C, in the stator 2, the stator core 7 is assembled to the outer circumference of a bearing housing 2a. In the stator core 7, a plurality of stator pole teeth 7b are provided, protruding outward in the radial direction from an annular core back part 7a. The stator core 7 may be a laminated core formed by lamination-pressing electromagnetic steel sheets or may be a block core made of a magnetic metal block. In the stator core 7, the peripheries of the stator pole teeth 7b are covered with an insulator (insulation bobbin) 7c, and a coil 7d is wound on the periphery of each insulator 7c. The rotor 1 is rotatably assembled by having the rotor shaft 3 inserted in the bearing housing 2a of the stator 2 and having the plate-like magnets 6 arranged opposite the stator pole teeth 7b of the stator core 7 (see FIG. 2D).

[0052] The configuration of the rotor 1 will now be described in detail.

[0053] As shown in FIG. 3A3 and FIG. 3B3, the plurality of plate-like magnets 6 divided in the circumferential direction are provided at a predetermined interval and spaced apart from each other at the inner circumferential surface 5a of the cylindrical rotor yoke 5. As the plate-like magnets 6, a rear earth magnet (for example, a neodymium magnet) having a rust-proofed surface is used, and the plate-like magnets 6 are bonded with a first adhesive 8a and a second adhesive 8b provided in the gap between the rotor yoke 5 and the flat plate-shaped plate-like magnets 6. Thus, the high-output plate-like magnets 6 can be bonded and fixed to the rotor yoke 5 without misalignment, using different types of adhesives, as will be described later.

[0054] At a bonding surface 6c of each plate-like magnet 6, a first bonding part 6a coated with the first adhesive 8a curing in a predetermined time and a second bonding part 6b coated with the second adhesive 8b for bonding and fixation that takes a longer curing time than the first adhesive 8a but has a higher bonding strength, are formed next to each other, as shown in FIGS. 5A and 5B. As the first adhesive 8a, for example, at least one of an ultraviolet-curing or anaerobic-curing adhesive and a quick-setting adhesive is used, and as the second adhesive 8b, for example, a thermosetting epoxy resin-based adhesive is used. Thus, casting ultraviolet rays onto the first adhesive 8a provided between the plate-like magnets 6 and the rotor yoke 5, creating an anaerobic state, bringing into contact with the bonding surface 6c, or combining these measures, cures the first adhesive 8a and therefore enables the plate-like magnet 6 to be easily partially bonded to the rotor yoke 5 in a relatively short time. FIG. 3B3 shows the state where the plate-like magnets 6 are bonded to the inner circumferential surface 5a of the rotor yoke 5. The application of the first adhesive 8a coating the first bonding part 6a of the plate-like magnets 6 and the second adhesive 8b coating the second bonding part 6b includes both a case where these adhesives are directly applied to the bonding surface 6c and a case where these adhesives are supplied in advance to a surface to be bonded (the inner circumferential surface 5a of the rotor yoke 5) and are then indirectly applied.

[0055] The plate-like magnet 6 is flat plate-shaped and an adhesive reservoir of the first adhesive 8a and the second adhesive 8b is formed in a void 9 formed between the curved inner circumferential surface 5a of the rotor yoke 5 and the bonding surface 6c of the flat plate-shaped plate-like magnet 6, as shown in FIG. 3B2. In this case, since no particular processing is needed for the plate-like magnet 6, the production cost can be reduced and the void 9 formed with the inner circumferential surface 5a (curved surface), which is the bonding surface of the rotor yoke 5, can be used as the adhesive reservoir of the first adhesive 8a and the second adhesive 8b and therefore the strength of partial bonding and fixed bonding can be maintained. Particularly if ultraviolet rays are cast at the time of partial bonding, a sufficient space for casting ultraviolet rays from the gap between the inner circumferential surface 5a (curved surface) and the end surface of the flat plate-shaped plate-like magnet 6 can be secured.

[0056] As shown in FIGS. 5A and 5B, it is preferable that, with respect to the bonding area formed at the bonding surface 6c of the plate-like magnet 6, the second bonding part 6b has an area equivalent to the area of the first bonding part 6a (see FIG. 5A) or greater (the second bonding part 6b>the first bonding part 6a) (see FIG. 5B). Thus, the bonding strength of the plate-like magnet 6 to the rotor yoke 5 can be maintained.

[0057] As described above, at least one of an ultraviolet-curing or anaerobic-curing adhesive and a quick-setting adhesive is used as the first adhesive 8a and a thermosetting epoxy resin-based adhesive is used as the second adhesive 8b. Thus, casting ultraviolet rays onto the first adhesive 8a provided between the plate-like magnet 6 and the rotor yoke 5, creating an anaerobic state, bringing these into contact with each other via a quick-setting adhesive, or combining these measures, cures the first adhesive 8a and therefore enables the plate-like magnet 6 to be easily partially bonded to the rotor yoke 5. Also, when the second adhesive 8b is heat-cured, the plate-like magnet 6 has been partially bonded to the rotor yoke 5 with the first adhesive 8a and therefore the plate-like magnet 6 does not become misaligned even if the viscosity of the second adhesive 8b temporarily drops in the heat-curing process.

[0058] While the case where the plate-like magnet 6 is a flat plate-shaped has been described, the plate-like magnet 6 may be in the shape of a curved plate with the bonding surface 6c having the same curvature as the rotor yoke 5, as shown in FIG. 3A1. In this case, the adhesive layer formed between the curved inner circumferential surface 5a of the rotor yoke 5 and the bonding surface 6c of the plate-like magnet 6 is formed uniformly in the circumferential direction of the bonding surface 6c, as shown in FIG. 3A2.

[0059] This case is similar to the case of the flat plate-like magnet in that the first bonding part 6a coated with the first adhesive 8a for partial bonding and the second bonding part 6b coated with the second adhesive 8b for bonding and fixation that is heat-cured are formed next to each other at the bonding surface 6c of the plate-like magnet 6, as shown in FIGS. 5A and 5B. FIG. 3A3 shows the state where the plate-like magnets 6 are bonded to the inner circumferential surface 5a of the rotor yoke 5.

[0060] Also, as shown in FIGS. 1C and 1C′, a positioning member 10 made of a resin for positioning, bonding, and fixing the plurality of plate-like magnets 6 to the inner circumferential surface 5a of the rotor yoke 5 is used. A resin-molded member is used as the positioning member 10, and the positioning member 10 has an annular coupling part 10a coupled in an annular shape and a plurality of partition members 10b that are formed, standing up in a pectinate shape from the annular coupling part 10a. The interval between the partition members 10b is approximately equivalent to or broader than the width dimension of the plate-like magnet 6. Also, at the annular coupling part 10a, a flange part 10c for positioning by coming into contact with an opening end of the rotor yoke 5 is provided, extending outward in the radial direction.

[0061] As shown in FIG. 1D, the positioning member 10 (partition members 10b) is inserted to the inner circumferential surface 5a from an opening at one end of the rotor yoke 5, and the plate-like magnets 6 are inserted between the partition members 10b from an opening at the other end and thus positioned in the radial direction and the axial direction to the inner circumferential surface 5a.

[0062] At this point, since the plate-like magnets 6 are coated with the first adhesive 8a at the first bonding part 6a, the plate-like magnets 6 can be positioned in the radial direction and the axial direction to the rotor yoke 5 and partially bonded by curing the first adhesive 8a (for example, by casting ultraviolet rays).

[0063] Also, in the state where the plate-like magnets 6 have been partially bonded to the inner circumferential surface 5a of the rotor yoke 5, the positioning member 10, which is no longer necessary, can be extracted and removed from the rotor yoke 5, as shown in FIG. 1E. After the positioning member 10 is removed from the rotor yoke 5, the epoxy resin-based second adhesive 8b is heat-cured, for example, at 100° C. to 180° C., thus bonding and fixing the plate-like magnets 6 at the second bonding part 6b. Although the viscosity of the second adhesive 8b temporarily drops in the heat curing process, the plate-like magnets 6 have been partially bonded with the first adhesive 8a and therefore do not become misaligned.

[0064] This can reduce the positioning member 10, which is originally unnecessary, reduce the production cost, and achieve a lighter weight of the rotor 1.

[0065] Also, since the plurality of plate-like magnets 6 are bonded and fixed at a predetermined interval to the rotor yoke 5, using the positioning member 10, cost reduction can be achieved, compared with an annular magnet, and the plate-like magnets 6 can be assembled to the rotor yoke 5 with high position accuracy in the radial direction and the axial direction and without misalignment.

[0066] In this way, the rotor 1 of the outer-rotor motor, in which the plurality of plate-like magnets 6 divided in the circumferential direction are fixed at a predetermined interval to the inner circumferential surface 5a of the rotor yoke 5, may be formed.

[0067] Meanwhile, as shown in FIGS. 4A and 4A′, the positioning member 10 may be used for positioning, bonding, and fixing the plurality of plate-like magnets 6 (curved plates) to an outer circumferential surface 5b of the rotor yoke 5 of an inner-rotor motor. The positioning member 10 is made of a resin-molded member and has the annular coupling part 10a coupled in an annular shape and the plurality of partition members 10b that are formed, standing up in a pectinate shape from the annular coupling part 10a. The flange part 10c may be not provided.

[0068] As shown in FIGS. 4A and 4A′, the partition members 10b of the positioning member 10 are fitted with the outer circumferential surface 5b from one end side in the axial direction of the rotor yoke 5 and the annular coupling part 10a is brought into contact with and attached to one end surface of the rotor yoke 5. The plurality of plate-like magnets 6 are each inserted between the partition members 10b from the other end surface side of the rotor yoke 5 and thus positioned in the radial direction and the axial direction.

[0069] At this point, since the plate-like magnets 6 are coated with the first adhesive 8a at the bonding surface 6c, the plate-like magnets 6 can be positioned to the rotor yoke 5 and partially bonded by curing the first adhesive 8a (for example, by casting ultraviolet rays).

[0070] In the state where the plate-like magnets 6 have been partially bonded, the positioning member 10, which is no longer necessary, can be extracted and removed from the rotor yoke 5. After the positioning member 10 is removed from the rotor yoke 5, the second adhesive 8b is heat-cured, for example, at 100° C. to 180° C., thus bonding and fixing the plate-like magnets 6 at the second bonding part 6b. Although the viscosity of the second adhesive 8b temporarily drops in the heat curing process, the plate-like magnets 6 have been partially bonded with the first adhesive 8a and therefore do not become misaligned.

[0071] In this way, the rotor 1 of the inner-rotor motor, in which the plurality of plate-like magnets 6 divided in the circumferential direction are fixed at a predetermined interval to the outer circumferential surface 5b of the rotor yoke 5 formed in a columnar shape, is provided, as shown in FIG. 4B.

[0072] The foregoing configurations of the rotor 1 achieve cost reduction and lighter weight, compared with an annular magnet, and enables the plate-like magnets 6 to be assembled with high position accuracy in the radial direction and the axial direction to the rotor yoke 5 regardless of whether it is an outer-rotor type or an inner-rotor type.

[0073] Also, the motor M has one of the foregoing rotors 1, and the stator 2 having the stator pole teeth 7b opposite the plate-like magnets 6 of the rotor 1, and thus can provide an outer-rotor motor or an inner-rotor motor that is inexpensive and light weight, has high assemblability, and can maintain motor characteristics.

[0074] The process of producing the rotor 1 of the outer-rotor motor will now be described with reference to FIGS. 1A to 1E and FIGS. 2A to 2D. In FIG. 1A, the rotor shaft 3 is fitted in a center part of the rotor hub 4 and assembled in a unified manner. As shown in FIG. 1B, the first bonding part 6a of the plurality of divided plate-like magnets 6 is each coated with the first adhesive 8a curing in a predetermined time. As the first adhesive 8a, for example, at least one of an ultraviolet-curing or anaerobic-curing adhesive and a quick-setting adhesive is used. Also, the second bonding part 6b next to the first bonding part 6a of the plate-like magnets 6 is each coated with the second adhesive 8b taking a longer curing time than the first adhesive 8a but having a higher bonding strength. As the second adhesive 8b, for example, a thermosetting epoxy resin-based adhesive is used.

[0075] Also, the process of applying the first and second adhesives 8a, 8b is not limited to the case where these adhesives are directly applied to the bonding surface 6c of the plate-like magnets 6, as shown in FIG. 1B, but also includes a case where at least one of the adhesives is indirectly applied to the surface to be bonded (the inner circumferential surface 5a) of the rotor yoke 5. That is, in FIG. 1B′, the first adhesive 8a may be applied in a circular manner to the inner circumferential surface corresponding to the first bonding part 6a from the side of the opening at one end of the rotor yoke 5, and the second adhesive 8b may be applied to the second bonding part 6b of the plate-like magnets 6.

[0076] Next, as shown in FIGS. 1C and 1C′, the positioning member 10 having the pectinate partition members 10b coupled to the annular coupling part 10a for positioning the plate-like magnets 6 in the radial direction and the axial direction is attached to the inner circumferential surface 5a of the rotor yoke 5. The partition members 10b are inserted from the side of the opening at the other end of the rotor yoke 5 and inserted until the flange part 10c comes into contact with the opening end.

[0077] Next, the plate-like magnets 6 are each inserted between the partition members 10b of the rotor yoke 5 with the positioning member 10 attached, from the side of the opening at the one end, and are arranged at a predetermined interval at the inner circumferential surface 5a of the rotor yoke 5 via the first adhesive 8a and the second adhesive 8b. FIG. 1D shows the state where the plate-like magnets 6 have been bonded to the rotor yoke 5.

[0078] In the state shown in FIG. 1D, the first adhesive 8a coating the plate-like magnets 6 is cured, thus partially bonding the plate-like magnets 6 at the first bonding part 6a to the rotor yoke 5. Specifically, ultraviolet rays are cast onto the first adhesive 8a in the case of an ultraviolet-curing adhesive, the adhesive is shut off from the outside air in the case of an anaerobic-curing adhesive, and the adhesive is brought into contact with the plate-like magnets 6 and then cured in the case of a quick-setting adhesive, thus partially bonding the plate-like magnets 6 to the rotor yoke 5.

[0079] At least one of an ultraviolet-curing or anaerobic-curing adhesive and a quick-setting adhesive may be used as the first adhesive 8a, and for example, a mixture of an ultraviolet-curing adhesive and an anaerobic-curing adhesive may be used. In this case, as the adhesive at the end surface of the plate-like magnets 6 is cured by ultraviolet irradiation and thus becomes shut off from the outside air, and therefore the adhesive inside (inside the void 9, see FIG. 3B2) is put in an anaerobic state and cured.

[0080] Next, as shown in FIG. 1E, the unnecessary positioning member 10 is extracted from the rotor yoke 5 with the plate-like magnets 6 partially bonded, via the opening at the other end.

[0081] Next, as shown in FIG. 2A, the rotor hub 4 and the rotor shaft 3 assembled together as shown in FIG. 1A are fitted in the opening at the one end of the rotor yoke 5 and assembled in a unified manner, thus assembling the rotor 1. FIG. 2B shows the assembled state of the rotor 1.

[0082] Next, the epoxy resin-based second adhesive 8b is heat-cured at a predetermined temperature within a range of 100° C. to 180° C., thus bonding and fixing the plate-like magnets 6 at the second bonding part 6b to the inner circumferential surface of the rotor yoke 5.

[0083] The plurality of plate-like magnets 6 may be magnetized before being bonded inside the rotor yoke 5 or may be magnetized after being bonded inside the rotor yoke 5.

[0084] While the plate-like magnets 6, if magnetized in advance, may attract each other and stick to each other when inserted in the rotor yoke 5, using the positioning member 10 eliminates the occurrence of such an inconvenience. Also, if the plate-like magnets 6 are magnetized after being bonded to the inner circumferential surface 5a of the rotor yoke 5, the work of assembling the plate-like magnets 6 is easier and is less susceptible to the influence of thermal demagnetization.

[0085] In this way, the rotor 1 is produced and assembled to the stator 2 and the motor M is thus produced. Specifically, as shown in FIG. 2C, the rotor 1 has the rotor shaft 3 inserted in the bearing housing 2a of the stator 2 and is rotatably supported by a bearing, not illustrated. The plate-like magnets 6 of the rotor yoke 5 are arranged opposite the stator pole teeth 7b of the stator core 7 and are rotatably assembled. FIG. 2D shows the motor M having the rotor 1 assembled to the stator 2.

[0086] In the case of the rotor 1 of the inner-rotor motor, the rotor 1 can be produced by a similar process that differs only in the method of applying the first and second adhesives 8a, 8b, as shown in FIGS. 4A and 4A′.

[0087] That is, the positioning member 10 having the pectinate partition members 10b coupled to the annular coupling part 10a for positioning the plate-like magnets 6 in the radial direction and the axial direction is attached to the outer circumferential surface 5b of the rotor yoke 5 assembled in a columnar shape having the rotor shaft 3 at its center, as shown in FIGS. 4A and 4A′. As shown in FIG. 4A, the first adhesive 8a may be applied in a circular manner to the outer circumferential surface 5b corresponding to the first bonding part 6a of the rotor yoke 5, and the second adhesive 8b may be applied to the bonding surface 6c corresponding to the second bonding part 6b of the plate-like magnets 6. Alternatively, as shown in FIG. 4A′, the first adhesive 8a for partial bonding may be applied to the bonding surface 6c of each plate-like magnet 6 and the second adhesive 8b may be applied to the second bonding part 6b of each plate-like magnet 6.

[0088] Next, as shown in FIGS. 4A and 4A′, the positioning member 10 having the pectinate partition members 10b coupled to the annular coupling part 10a for positioning the plate-like magnets 6 in the radial direction and the axial direction is attached to the outer circumferential surface 5b of the rotor yoke 5. The partition members 10b are fitted along the outer circumferential surface 5b of the rotor yoke 5 and are fitted until the annular coupling part 10a comes into contact with the end surface of the rotor yoke 5.

[0089] Next, the plate-like magnets 6 are each inserted between the partition members 10b of the rotor yoke 5 with the positioning member 10 attached, and are positioned and arranged at a predetermined interval at the outer circumferential surface 5b of the rotor yoke 5 via the first adhesive 8a and the second adhesive 8b. FIG. 4B shows the state where the plate-like magnets 6 have been bonded to the rotor yoke 5.

[0090] In the state shown in FIG. 4B, the first adhesive 8a coating the plate-like magnets 6 is cured, thus partially bonding the plate-like magnets 6 at the first bonding part 6a to the rotor yoke 5. Specifically, ultraviolet rays are cast onto the first adhesive 8a in the case of an ultraviolet-curing adhesive, the adhesive is shut off from the outside air in the case of an anaerobic-curing adhesive, and the adhesive is brought into contact with the plate-like magnets 6 and then cured in the case of a quick-setting adhesive, thus partially bonding the plate-like magnets 6 to the rotor yoke 5.

[0091] Next, as shown in FIG. 4C, the unnecessary positioning member 10 is extracted from the rotor yoke 5 with the plate-like magnets 6 partially bonded, via the opening at the other end, thus assembling the rotor 1.

[0092] Finally, the epoxy resin-based second adhesive 8b is heat-cured at a predetermined temperature within a range of 100° C. to 180° C., thus bonding and fixing the plate-like magnets 6 at the second bonding part 6b to the outer circumferential surface 5b of the rotor yoke 5. In this way, the rotor 1 of the inner-rotor motor is produced.

[0093] The plurality of plate-like magnets 6 may be magnetized before being bonded to the rotor yoke 5 or may be magnetized after being bonded inside the rotor yoke 5.

[0094] According to the foregoing method of producing the rotor 1, attaching the positioning member 10 having the pectinate partition members 10b coupled to the annular coupling part 10a for positioning in the radial direction and the axial direction, to the rotor yoke 5, enables the positioning and arrangement of the plate-like magnets 6 in the radial direction and the axial direction between the partition members 10b.

[0095] Also, the positioning member 10 can be extracted from the rotor yoke 5 after the plate-like magnets 6 are partially bonded to the rotor yoke 5 at the first bonding part 6a by curing the first adhesive 8a coating the plate-like magnets 6, and therefore a reduction in the number of components, a reduction in the production cost, and a lighter weight of the rotor 1 can be achieved by omitting the positioning member 10, which is originally unnecessary.

[0096] Also, since the plate-like magnets 6 are bonded and fixed to the rotor yoke 5 by heat-curing the second adhesive 8b coating the plate-like magnets 6 after the positioning member 10 is removed from the rotor yoke 5, the plate-like magnets 6 can be bonded and fixed with high position accuracy.

[0097] As described above, the rotor 1 that achieves a reduction in the number of components, a reduction in the production cost, and a lighter weight, can be provided. Also, a method of producing a rotor that enables the plurality of plate-like magnets 6 to be positioned in the radial direction and the axial direction and bonded and fixed to the rotor yoke 5 with high position accuracy and thus achieves high assemblability, can be provided.

[0098] Also, the motor M that is inexpensive, has high assemblability, and can maintain motor characteristics, by using the rotor 1, can be provided.