JP2019013115A - Rotor, motor, and method of manufacturing rotor - Google Patents

Abstract

To provide a rotor, a motor, and a method of manufacturing the rotor capable of suppressing or preventing deviation of a magnet in an axial direction.SOLUTION: A motor comprises a rotor that can rotate, and a stator that rotates and drives the rotor. The rotor comprises a rotor core 11, and a plurality of magnets 12 arranged in a circumferential direction. Each magnet 12 is provided on a rotor core inner lateral face 11a at the radial inside of the rotor core 11. The rotor core 11 has a projection 112 that protrudes radially inward from the inner lateral face at the radial inside of the rotor core 11, and includes an upper projection 1121 provided at an axial upper side of the magnet 12 and a lower projection 1122 provided at an axial lower side of the magnet 12. An interval between a projection opposed surface 112a axially opposed to an axial end surface 12b of the magnet 12 at least at one of the upper projection 1121 and the lower projection 1122, and the axial end surface 12b, becomes larger as it goes radially inward.SELECTED DRAWING: Figure 4A

Description

  The present invention relates to a rotor, a motor, and a method for manufacturing the rotor.

  2. Description of the Related Art Conventionally, as in Patent Document 1, for example, an outer rotor type motor in which a permanent magnet is fixed to a rotor core made of laminated electromagnetic steel sheets is known. In this patent document 1, in order to suppress the axial displacement of the permanent magnet, a triangular permanent magnet fixing portion is provided on the electromagnetic steel plate at the lowermost part of the laminated electromagnetic steel plate. A part of the permanent magnet fixing portion is shaped to protrude into the concave groove portion of the rotor core.

JP 2012-217320 A

  However, in Patent Document 1, since the permanent magnet fixing portion is provided only on the lower side in the axial direction of the laminated electrical steel sheet, the displacement of the permanent magnet cannot be suppressed on both the upper side in the axial direction and the lower side in the axial direction. Moreover, when fixing a permanent magnet to a rotor core, since a permanent magnet contacts a permanent magnet fixing | fixed part in radial direction, there exists a problem that it is difficult to attach a permanent magnet to the inner surface of a rotor core along a permanent magnet fixing | fixed part.

  An object of this invention is to provide the rotor, the motor, and the manufacturing method of a rotor which can suppress or prevent the shift | offset | difference in the axial direction of a magnet.

  An exemplary rotor of the present invention includes a rotor core that annularly surrounds a central axis extending in the vertical direction and is formed of laminated steel plates, and a plurality of magnets arranged in a circumferential direction, and the plurality of magnets have a diameter of the rotor core. The rotor core has a protruding portion that protrudes radially inward from an inner surface on the radially inner side of the rotor core, and the protruding portion is provided on an upper side in the axial direction of the magnet. A projecting portion and a lower projecting portion provided on the lower side in the axial direction of the magnet, and at least one of the upper projecting portion and the lower projecting portion is opposed to the axial end surface of the magnet in the axial direction. The distance between the projecting portion facing surface and the axial end surface of the magnet increases as it goes radially inward.

  An exemplary motor of the present invention includes the above-described rotor that is rotatable about the central axis, and a stator that rotationally drives the rotor.

  An exemplary rotor manufacturing method according to the present invention includes a step of annularly enclosing a central axis extending in the vertical direction and forming a rotor core made of laminated steel sheets, and a plurality of magnets provided on an inner side surface of the rotor core on a radially inner side. And the step of forming the rotor core includes a step in which a plurality of annular first steel plates are laminated in the axial direction, and a radial distance from an inner surface on the radially inner side to the central axis is A step in which a second steel plate and a third steel plate smaller than the first steel plate are formed; a step in which the second steel plate is laminated on the axially upper side of the first steel plate; and an axially lower side of the first steel plate. A step of laminating the third steel plate, and in the step of providing the magnet, each of the magnets is located radially inward of the second steel plate. In the step of forming the second steel plate and the third steel plate, the second steel plate and the third steel plate are provided between the end portion and the inner end portion on the radial inner side of the third steel plate. The inner end of the at least one steel plate in the radial direction is deformed by being pressed by a jig having an inclined surface, and a second surface is formed on the first surface facing the axial direction of the at least one steel plate. The second surface is a surface that faces in the axial direction toward the side opposite to the direction in which the first surface faces in the axial direction, the step of laminating the second steel plate, and the third steel plate. In at least one of the steps of laminating, the second surface is directed toward the first steel plate in the axial direction.

  According to the exemplary rotor, motor, and manufacturing method of the rotor of the present invention, the displacement of the magnet in the axial direction can be suppressed or prevented.

FIG. 1 is a perspective view illustrating a configuration example of a ceiling fan. FIG. 2 is a cross-sectional view showing a configuration example of the motor. FIG. 3 is a perspective view of the rotor core to which the magnet is fixed. FIG. 4A is a longitudinal sectional view of the rotor core viewed from the circumferential direction. FIG. 4B is a cross-sectional view of the rotor core viewed from the axial direction. FIG. 5 is an exploded perspective view illustrating a configuration example of a housing that accommodates the rotor core. FIG. 6 is an exploded perspective view showing another configuration example of the housing that houses the rotor core. FIG. 7A is a conceptual diagram for explaining a rotor core formation step. Drawing 7B is a key map for explaining the formation process of the 2nd steel plate and the 3rd steel plate laminated on the axial direction both sides of a plurality of 1st steel plates.

  Hereinafter, exemplary embodiments of the present invention will be described with reference to the drawings.

  In the present specification, in the motor 110 of the ceiling fan 100, a direction parallel to the central axis CA is referred to as an “axial direction”. Further, in the axial direction, a direction from the stator core 21 toward the bearing 3 is referred to as “upper axial direction”, and a direction from the bearing 3 toward the stator core 21 is referred to as “lower axial direction”. Also, on the surface of each component, the surface facing upward in the axial direction is referred to as “upper surface”, and the surface facing downward in the axial direction is referred to as “lower surface”.

  In addition, a direction orthogonal to the central axis CA is referred to as a “radial direction”, and a rotation direction around the central axis CA is referred to as a “circumferential direction”. Further, of the radial directions, a direction toward the central axis CA is referred to as “radial inner side”, and a direction away from the central axis CA is referred to as “radial outer side”. Further, of the side surfaces of each component, a side surface facing radially inward is referred to as an “inner surface”, a side surface facing radially outward is referred to as an “outer surface”, and a side surface facing in the circumferential direction is referred to as a “circumferential side surface”. Call.

  Note that the direction and surface designations described above do not indicate the positional relationship and direction when incorporated in an actual device.

<1. Embodiment>
<1-1. Configuration of ceiling fan>
FIG. 1 is a cross-sectional view illustrating a configuration example of the ceiling fan 100. The ceiling fan 100 is a blower device that includes a motor 110 and blades 120. The blade 120 is rotatable about the central axis CA and is attached to the motor 110. The motor 110 rotates the blade 120. The number of blades 120 is three in FIG. 1, but is not limited to this example, and may be one or a plurality other than three. The motor 110 is an outer rotor type brushless DC motor included in the ceiling fan 100 in the present embodiment.

<1-2. Motor configuration>
Next, the configuration of the motor 110 will be described. FIG. 2 is a cross-sectional view illustrating a configuration example of the motor 110. In FIG. 2, the motor 110 is cut along a cutting plane including the central axis CA.

  As shown in FIG. 2, the motor 110 includes a rotor 1 that can rotate around a central axis CA that extends in the vertical direction, a stator 2 that rotationally drives the rotor 1, and a bearing 3.

  As illustrated in FIG. 2, the rotor 1 includes a rotor core 11, a plurality of magnets 12, an adhesive member 13, and a housing 14. In addition, each component of the rotor 1 and the manufacturing method of the rotor 1 are demonstrated later.

  The stator 2 includes a stator core 21, an insulator 22, a coil portion 23, and a shaft 24. The stator core 21 is an iron core member made of, for example, electromagnetic steel plates laminated in the axial direction, and faces the magnet 12 of the rotor 1 in the radial direction. The insulator 22 is an insulating member using, for example, a resin material and covers at least a part of the stator core 21. The coil portion 23 is made of a conductive wire wound around the stator core 21 via the insulator 22. The shaft 24 is a cylindrical member extending in the axial direction. A stator core 21 is attached to the shaft 24.

  The bearing 3 is attached between the housing 14 of the rotor 1 and the shaft 24, and supports the rotor 1 rotatably with respect to the shaft 24.

<1-3. Each component of rotor>
<1-3-1. Rotor core, magnet, and adhesive member>
Next, the rotor core 11, the magnet 12, and the adhesive member 13 will be described. FIG. 3 is a perspective view of the rotor core 11 to which the magnet 12 is fixed. FIG. 4A is a longitudinal sectional view of the rotor core 11 as seen from the circumferential direction. FIG. 4B is a cross-sectional view of the rotor core 11 as viewed from the axial direction. 4A shows a cross section taken along line AA in FIG. 3, and FIG. 4B shows a cross section taken along line BB in FIG.

  The rotor core 11 surrounds a central axis CA extending in the vertical direction in an annular shape, and is composed of a laminated steel plate 15 to be described later on which electromagnetic steel plates and the like are laminated. The rotor core 11 includes an annular portion 111, a protruding portion 112, a convex portion 113, and a protruding portion 114.

  The annular portion 111 has an annular shape centered on the central axis CA. The inner side surface of the annular portion 111 of the rotor core 11 on the radially inner side includes a plurality of rotor core inner side surfaces 11a. The rotor core inner surface 11a is a region to which the magnets 12 are fixed, and is opposed to a magnet outer surface 12a (described later) facing the radial outer side of each magnet 12 in the radial direction. The rotor core inner surface 11a and the magnet outer surface 12a are parallel to each other. Since the magnet outer surface 12a and the rotor core inner surface 11a are parallel to each other, the counter electromotive force of the motor 110 when the rotor 1 is attached to the motor 110 can be improved. Moreover, the deterioration of the yield of the magnet 12 in a manufacturing process can be suppressed compared with the case where the magnet outer surface 12a and the rotor core inner surface 11a are curved surfaces. For example, if the inner surface 11a of the rotor core is a curved surface, it is necessary to process the magnet 12 so that the outer surface 12a of the magnet is a curved surface that conforms to the shape of the inner surface 11a of the rotor core. The yield of the magnet 12 in the manufacturing process is deteriorated.

  There are a plurality of protrusions 112, which protrude radially inward from the inner surface of the rotor core 11 on the radially inner side. More specifically, the protruding portion 112 protrudes radially inward from the annular portion 111. The protruding portion 112 includes an upper protruding portion 1121 and a lower protruding portion 1122. The upper protrusion 1121 is provided on the upper side in the axial direction of the magnet 12. The lower protrusion 1122 is provided on the lower side in the axial direction of the magnet 12. In this embodiment, the same number of upper protrusions 1121 as the magnets 12 and the same number of lower protrusions 1122 as the magnets 12 are arranged in the circumferential direction, but the configuration of the protrusions 112 is not limited to this example. For example, an annular shape in which the inner diameter of at least one of the upper protruding portion 1121 and the lower protruding portion 1122 is smaller than the inner diameter of the annular portion 111 may be used. Alternatively, the number of the projecting portions 12 of at least one of the upper projecting portion 1121 and the lower projecting portion 1122 may be smaller than the number of the magnets 12.

  Further, the protruding portion facing surface 112a facing the axial end surface 12b of the magnet 12 in the protruding portion 112 in the axial direction is an inclined surface. Therefore, the distance between the protruding portion facing surface 112a and the axial end surface 12b of the magnet 12 increases as it goes radially inward. In the present embodiment, the protruding portion facing surface 112a in both the upper protruding portion 1121 and the lower protruding portion 1122 is an inclined surface. More specifically, the lower surface of the upper projecting portion 1121 and the upper surface of the lower projecting portion 1122 are inclined surfaces in which the distance between the axial end surface 12b increases inward in the radial direction. However, the present invention is not limited to this example, and one protruding portion facing surface 112a of the upper protruding portion 1121 and the lower protruding portion 1122 may be an inclined surface.

  In other words, at least one of the upper protrusion 1121 and the lower protrusion 1122 has a gap between the axial end surface 12b and the axially opposite end surface 12b, which is opposed to the axial end surface 12b of the magnet 12 in the axial direction. It only needs to increase as it goes inward.

  By so doing, axial displacement of the magnet 12 can be suppressed or prevented by the upper protrusion 1121 provided on the upper side in the axial direction of the magnet 12 and the lower protrusion 1122 provided on the lower side in the axial direction of the magnet 12.

  Further, when the magnet 12 is fixed to the rotor core 11, the magnet 12 can be inserted between the protruding portions 112 along the protruding portion facing surface 112 a which is an inclined surface. Therefore, the magnet 12 can be easily inserted, and the positioning of the magnet 12 in the axial direction can be easily performed.

  In addition, the circumferential length of the upper protruding portion 1121 and the circumferential length of the lower protruding portion 1122 are equal to the circumferential length of the magnet 12 in this embodiment. However, the present invention is not limited to this example, and at least one of the circumferential length of the upper projection 1121 and the circumferential length of the lower projection 1122 is longer than or equal to the circumferential length of the magnet 12. If it is. This makes it easier to suppress or prevent the axial displacement of the magnet 12. As will be described later, when the adhesive member 13 is provided between the protruding portion facing surface 112 a and the magnet 12, the circumferential length of the protruding portion 112 having the protruding portion facing surface 112 a is the circumferential length of the magnet 12. If it is above, it can suppress or prevent that this adhesion member 13 protrudes outside the rotor core 11 beyond the protrusion part 112 in an axial direction. Further, in the protruding portion 112, the protruding portion facing surface 112a facing the axial end surface 12b of the magnet 12 in the axial direction is an inclined surface, and the protruding portion facing surface 112a and the axial end surface 12b of the magnet 12 are spaced apart at an angle. doing. Therefore, the adhesive member 13 is easily held by the surface tension.

  The protrusion 113 protrudes radially inward from the inner side surface of the annular portion 111 of the rotor core 11 between the adjacent magnets 12 on the radially inner side. In this way, the circumferential shift of the magnet 12 can be suppressed or prevented by the convex portions 113 provided on both sides of the magnet 12 in the circumferential direction.

  Moreover, the convex part opposing surface 113a which opposes the magnet 12 in the circumferential direction in the convex part 113 is an inclined surface. Therefore, the interval between the convex facing surface 113a and the circumferential end surface 12c facing the circumferential direction of the magnet 12 increases as it goes radially inward. In this way, when the magnet 12 is provided on the rotor core 11, the magnet 12 can be inserted between the convex portions 113 along the convex portion facing surface 113a of the convex portion 113 having the inclined surface as described above. Therefore, the positioning of the magnet 12 in the circumferential direction can be easily performed. In the present embodiment, both the convex facing surfaces 113a on both sides in the circumferential direction of the convex 113 are inclined surfaces as described above. However, the present invention is not limited to this example, and the convex facing surface 113a on at least one side in the circumferential direction of the convex 113 may be an inclined surface as described above.

  The convex 113 may be formed on a part of the rotor core 11 in the axial direction. In this embodiment, the convex part 113 is formed in the steel plate which comprises the rotor core 11 among the steel plates 15 which oppose the magnet 12 in radial direction. That is, at least one steel plate (for example, a second steel plate 152 described later) provided at the upper end portion on the upper side in the axial direction of the rotor core 11 and having the upper protruding portion 112a, and provided at the lower end portion on the lower side in the axial direction of the rotor core 11. The protrusion 113 is not formed on at least one steel plate having the lower protrusion 112b. The steel plate that faces the magnet 12 in the radial direction corresponds to, for example, a first steel plate 151 described later. At least one steel plate having the upper protrusion 112a corresponds to, for example, a second steel plate 152 described later. This corresponds to at least one steel plate having the lower protrusion 112b, for example, a third steel plate 153 described later.

  The protrusion 114 protrudes radially outward from the outer surface on the radially outer side of the annular portion 111 of the rotor core 11 and extends in the axial direction. In addition, although the number of the protrusion parts 114 is four in this embodiment, it is not limited to this illustration, A single number or multiple other than four may be sufficient.

  The plurality of magnets 12 are provided on the inner side surface on the radially inner side of the annular portion 111 of the rotor core 11, and are arranged in the circumferential direction on the inner side surface.

  The adhesive member 13 is provided between the annular portion 111 of the rotor core 11 and each magnet 12, and fixes the plurality of magnets 12 to the rotor core 11.

  More specifically, as shown in FIG. 4A, the adhesive member 13 is provided between the magnet outer surface 12a and the rotor core inner surface 11a of each magnet 12, and the plurality of magnets 12 are connected to the annular portion 111. Secure to.

  Further, as shown in FIG. 4A, the adhesive member 13 is further provided between the axial end surface 12b of each magnet 12 and the protruding portion facing surface 112a. The axial end surface 12b is an upper surface and a lower surface of each magnet 12, and faces the protruding portion facing surface 112a in the axial direction. By doing so, the gaps between the projecting portion facing surface 112 a that is inclined with respect to the magnet 12 and the axial end surface 12 b are used as a pool for the adhesive member 13, so that the plurality of magnets 12 are disposed in the projecting portion 112. Can be fixed.

  Further, as shown in FIG. 4B, the adhesive member 13 is further provided between the circumferential end surface 12c of each magnet 12 and the convex facing surface 113a. The circumferential end surface 12c is an end surface in the circumferential direction of each magnet 12, and faces the convex facing surface 113a in the circumferential direction. In this way, the gaps between the circumferential end face 12 c and the convex facing surface 113 a that is inclined with respect to the magnet 12 are used for the accumulation of the adhesive member 13, and the plurality of magnets 12 are arranged in the convex 113. Can be fixed. Further, the circumferential end surface 12c of each magnet 12 and the convex facing surface 113a are separated from each other with an angle, whereby the adhesive member 13 is easily held by surface tension.

<1-3-2. Housing>
Next, the housing 14 will be described. The housing 14 includes an upper housing part 14a, a cylindrical bearing holding part 14b, and a lower housing part 14c (see FIG. 2). FIG. 5 is an exploded perspective view illustrating a configuration example of the housing 14 that accommodates the rotor core 11. In FIG. 5, the lower housing portion 14 c is not shown for easy understanding of the configuration.

  The upper housing part 14a is annular when viewed from the lower side in the axial direction. The bearing holding portion 14b extends axially upward from the inner peripheral edge on the radially inner side of the upper housing portion 14a. The bearing 3 is provided inside the bearing holding portion 14b, and the shaft 24 is inserted therethrough. The lower housing part 14c is attached to the lower side in the axial direction of the upper housing part 14a, and covers the lower end part of the upper side of the upper housing part 14a in the axial direction.

  Further, the upper housing 14 a of the housing 14 has a concave portion 141 and a cylindrical cylindrical portion 142. The recessed portion 141 is recessed upward in the axial direction at the central portion of the upper housing portion 14a through which the central axis CA passes, and accommodates the rotor core 11 therein. An opening leading to the bearing holder 14 b is provided on the bottom surface of the recess 141.

  The cylindrical portion 142 extends downward in the axial direction from the bottom surface of the concave portion 141. In the recess 141, the rotor core 11 is accommodated in the cylindrical portion 142 and fixed. The cylindrical portion 142 has the same number (four in FIG. 5) of groove portions 143 as the protruding portions 114. The groove portion 143 is recessed from the inner side surface on the radially inner side of the cylindrical portion 142 to the radially outer side, and extends in the axial direction. More specifically, the groove portion 143 penetrates the cylindrical portion 142 in the radial direction in the present embodiment, and the lower end portion in the axial direction of the cylindrical portion 142 is opened.

  When the rotor core 11 is accommodated in the cylindrical portion 142, at least a part of the protruding portion 114 is inserted into the groove portion 143. By inserting the protrusion 114 of the rotor core 11 into the groove 143 of the cylindrical portion 142 of the housing 14, the position of the rotor core 11 with respect to the housing 14 can be prevented from shifting in the circumferential direction. Further, even if the concave portion 141 and the cylindrical portion 142 are provided in the housing 14 by cutting or the like, the groove portion 143 can be provided on the inner surface of the cylindrical portion 142 without hindering the cutting processing.

  In addition, the structure in which the rotor core 11 is accommodated in the cylinder part 142 is not limited to the illustration of FIG. FIG. 6 is an exploded perspective view showing another configuration example of the housing 14 that accommodates the rotor core 11. As shown in FIG. 6, the cylindrical portion 142 may have a protruding portion 144, and the rotor core 11 may have a groove portion 115. And when the rotor core 11 is accommodated in the cylinder part 142, at least one part of the projection part 144 may be inserted in the groove part 115. FIG. In FIG. 6, the protruding portion 144 is provided on the inner side surface of the cylindrical portion 142 on the radially inner side, and protrudes radially inward from the cylindrical portion 142. Moreover, the groove part 115 is provided in the outer surface in the radial direction outer side of the annular part 111 of the rotor core 11, is dented in the radial direction inner side, and extends in the axial direction. In this way, the protrusion 144 of the housing 14 is inserted into the groove 115 of the rotor core 11 so that the position of the rotor core 11 with respect to the housing 14 can be prevented from shifting in the circumferential direction.

<1-4. Manufacturing method of rotor>
Next, an example of a method for manufacturing the rotor 1 will be described. The method for manufacturing the rotor 1 includes a rotor core forming step, a magnet fixing step, and an attaching step.

<1-4-1. Rotor core formation process>
FIG. 7A is a conceptual diagram for explaining a rotor core formation step. FIG. 7B is a conceptual diagram for explaining a process of forming the second steel plate 152 and the third steel plate 153 that are laminated on both sides in the axial direction of the plurality of first steel plates 151. In the rotor core forming step, the rotor core 11 made of the laminated steel plate 15 is formed by surrounding the central axis CA extending in the vertical direction in an annular shape. The rotor core forming step has first to fourth steps.

  In the first step, as shown in FIG. 7A, an annular first steel plate 151 is formed and laminated in the axial direction. More specifically, the first process includes a punching process and a stacking process. In the punching step, a plurality of annular first steel plates 151 are formed, for example, by punching a magnetic steel plate. In addition, the convex part 15b which comprises the convex part 113 is formed in the inner periphery on the radial inside of the formed 1st steel plate 151. As shown in FIG. In addition, a protruding portion 15c constituting the protruding portion 114 is formed on the outer peripheral edge on the radially outer side of the formed first steel plate 151. In the laminating step, each first steel plate 151 is laminated in the axial direction. At this time, the circumferential positions of the convex portions 15b of the first steel plates 151 are aligned, and the circumferential positions of the protruding portions 15c are aligned. In other words, the convex portions 15b of the first steel plates 151 are arranged in the axial direction, and the protruding portions 15c are also arranged in the axial direction.

  In the second step, as shown in FIG. 7B, a second steel plate 152 and a third steel plate 153 are formed. More specifically, the second step includes a punching step and a surface punching step.

  In the punching step, the annular steel plate 150 is formed by, for example, punching a magnetic steel plate. A projecting portion 15 a constituting the projecting portion 112 is formed on the inner peripheral edge on the radially inner side of the steel plate 150. In addition, a protruding portion 15 c constituting the protruding portion 114 is formed on the outer peripheral edge on the radially outer side of the steel plate 150. Further, the radial distances D2 and D3 from the inner end portion on the radially inner side of the projecting portion 15a to the central axis CA are the central axis CA from the inner side surface 151a of the rotor core 11 between the adjacent convex portions 15b of the first steel plate 151. It is smaller than the radial distance D1 until. The inner side surface 151a constitutes the rotor core inner side surface 11a.

  In the beveling process, the protruding portion 15a of the steel plate 150 used as the second steel plate 152 and the third steel plate 153 is deformed by being pressed in the axial direction by a jig having an inclined surface. As a result, the second surface 150 b is formed on the first surface 150 a facing the axial direction of the steel plate 150. The second surface 150 b corresponds to the protruding portion facing surface 112 a that is an inclined surface in the protruding portion 112. The second surface 150b is an inclined surface that faces toward the opposite side to the direction in which the first surface 150a faces in the axial direction as it goes radially inward.

  In the present embodiment, since the plurality of protruding portions 112 of the rotor core 11 are arranged in the circumferential direction, a plurality of protruding portions 15a are formed on the inner peripheral edge of the steel plate 150 in the punching step of the second step. The However, when the protruding portion 112 of the rotor core 11 is annular, the protruding portion 15 a is not formed on the inner peripheral edge of the steel plate 150 used as the second steel plate 152 and the third steel plate 153.

  In the rotor forming step, the steel plate 150 provided with the second surface 150b is used for both the second steel plate 152 and the third steel plate 153 in this embodiment, but is not limited to this example. It may be used for one of the second steel plate 152 and the third steel plate 153. In this case, the steel plate formed by the punching process in the second step is used as it is for the other of the second steel plate 152 and the third steel plate 153.

  In the third step, as shown in FIG. 7A, the steel plate 150 is laminated as the second steel plate 152 on the upper side in the axial direction of the laminated first steel plates 151. At this time, the steel plate 150 is laminated with the second surface 150b formed on the protruding portion 15a facing downward in the axial direction. At this time, the circumferential position of the protruding portion 15 c of the steel plate 150 is aligned with the circumferential position of the protruding portion 15 c of the first steel plate 151. In other words, the protruding portion 15c of the first steel plate 151 and the protruding portion 15c of the steel plate 150 that becomes the second steel plate 152 are arranged in the axial direction.

  In the fourth step, as shown in FIG. 7A, a steel plate 150 is laminated as a third steel plate 153 on the lower side in the axial direction of the laminated first steel plates 151. At this time, the steel plate 150 is laminated with the second surface 150b formed on the protruding portion 15a facing upward in the axial direction. At this time, the circumferential position of the protruding portion 15 c of the steel plate 150 is aligned with the circumferential position of the protruding portion 15 c of the first steel plate 151. In other words, the protruding portion 15c of the first steel plate 151 and the protruding portion 15c of the steel plate 150 that becomes the third steel plate 153 are arranged in the axial direction.

<1-4-2. Magnet fixing process>
In the magnet fixing step, a plurality of magnets 12 are provided on the inner side surface on the radially inner side of the plurality of stacked first steel plates 151. At this time, each magnet 12 includes a second surface 150b of the second steel plate 152 stacked on the upper side in the axial direction of the first steel plate 151 and a second steel plate stacked on the lower side in the axial direction of the first steel plate 151. 152 between the second surface 150b and the second surface 150b.

<1-4-3. Installation process>
In the attaching process, the rotor core 11 is accommodated in the cylindrical portion 142 of the housing 14 (see FIG. 5). At this time, at least a part of the protrusion 114 is inserted into the groove 143.

<1-4-4. Summary>
As described above, the method for manufacturing the rotor 1 includes a step in which the rotor core 11 formed by surrounding the central axis CA extending in the vertical direction and annularly formed of the laminated steel plates 15 is formed on the inner side surface of the rotor core 11 on the radially inner side. A step of providing a plurality of magnets 12. The steps of forming the rotor core 11 include a step in which a plurality of annular first steel plates 151 are laminated in the axial direction, and distances D2 and D3 in the radial direction from the inner end portion on the radially inner side to the central axis CA are the first steel plates. A step in which a second steel plate 152 and a third steel plate 153 smaller than 151 are formed; a step in which the second steel plate 152 is laminated on the upper side in the axial direction of the first steel plate 151; and a lower side in the axial direction of the first steel plate 151. The third steel plate 153 is laminated. In the step of providing the magnets 12, each magnet 12 is provided between the inner end portion on the radially inner side of the second steel plate 152 and the inner end portion on the radially inner side of the third steel plate 153. In the step of forming the second steel plate 152 and the third steel plate 153, the inner end portion in the radial direction of at least one of the second steel plate 152 and the third steel plate 153 is pressed with a jig having an inclined surface. As a result, the second surface 150b is formed on the first surface 150a facing the axial direction of at least one of the steel plates. The second surface 150b is a surface that faces in the axial direction toward the opposite side to the direction in which the first surface 150a faces in the axial direction. In at least one of the step of laminating the second steel plate 152 and the step of laminating the third steel plate 153, the second surface 150b is directed to the first steel plate 151 side in the axial direction.

  The inner end on the radially inner side of at least one of the second steel plate 152 laminated on the upper side in the axial direction of the first steel plate 151 and the third steel plate 153 laminated on the lower side in the axial direction of the first steel plate 151. The part is subjected to a chamfering process. By this processing, the second surface 150b becomes an inclined surface. The second surface 150b faces the magnet 12 in the axial direction. That is, the distance between the protruding portion facing surface 112a and the axial end surface 12b of the magnet 12 can be increased toward the radially inner side. For this reason, in the step in which the magnet 12 is provided, the magnet 12 can be inserted between the projecting portions 112 along the projecting portion facing surface 112a which is an inclined surface. Therefore, the magnet 12 can be easily inserted, and the positioning of the magnet 12 in the axial direction can be easily performed. Note that the inner ends of the second steel plate 152 and the third steel plate 153 on the radially inner side correspond to the protruding portions 112.

<2. Other>
The embodiment of the present invention has been described above. The scope of the present invention is not limited to the above-described embodiment. The present invention can be implemented with various modifications without departing from the spirit of the invention. In addition, the items described in the above embodiments can be arbitrarily combined as long as no contradiction occurs.

  For example, in the above-described embodiment, the motor 110 is an outer rotor type brushless DC motor included in the ceiling fan 100 in the present embodiment. However, the present invention is not limited to these examples, and the motor 110 may be provided in a device other than the ceiling fan 100 or may be an inner rotor type. In addition, when the motor 110 is an inner rotor type | mold, the position in the radial direction of the component of the motor 110 may be reversed. For example, when the motor 110 is an inner rotor type, the plurality of magnets 12 are provided on the outer surface on the radially outer side of the rotor core 11, and the protruding portion 112 of the rotor core 11 protrudes radially outward from the outer surface of the annular portion 111. To do. And the space | interval between at least one protrusion part opposing surface 112a of the upper side protrusion part 1121 and the lower side protrusion part 1122 and the axial direction end surface 11b becomes large as it goes to radial direction outer side.

  The present invention is useful, for example, for a motor having a rotor in which a magnet is provided on a side surface in the radial direction of a rotor core, and a method for manufacturing the rotor.

DESCRIPTION OF SYMBOLS 100 ... Ceiling fan, 110 ... Motor, 120 ... Blade, 1 ... Rotor, 11 ... Rotor core, 11a ... Rotor core inner surface, 111 ... Ring part, 112 ...・ Projection part, 112a... Projection part facing surface, 1121... Upper projection part, 1122... Lower projection part, 113. Projection, 115 ... groove, 12 ... magnet, 12a ... magnet outer surface, 12b ... axial end surface, 12c ... circumferential end surface, 13 ... adhesive member, 14 ... Housing, 14a ... Upper housing, 14b ... Bearing holder, 14c ... Lower housing, 141 ... Recess, 142 ... Tube, 143 ... Groove, 144 ... Projection, 15 ... Laminated steel sheet, 15a ... Projection portion, 15b ... convex portion, 15c ... projection portion, 150 ... steel plate, 150a ... first surface, 150b ... second surface, 151 ... first steel plate, 151a ... -Inner side surface, 152 ... second steel plate, 153 ... third steel plate, 2 ... stator, 21 ... stator core, 22 ... insulator, 23 ... coil part, 24 ... shaft 3 ... Bearing, CA ... Center axis, D1-D3 ... Radial distance

Claims (10)

A rotor core that surrounds the central axis extending in the vertical direction and is formed of laminated steel sheets;
A plurality of magnets arranged in the circumferential direction,
The plurality of magnets are provided on an inner surface on the radially inner side of the rotor core,
The rotor core has a protruding portion that protrudes inward in the radial direction from the inner side surface in the radial direction of the rotor core;
The protrusion includes an upper protrusion provided on the upper side in the axial direction of the magnet, and a lower protrusion provided on the lower side in the axial direction of the magnet,
In at least one of the upper protruding portion and the lower protruding portion, a distance between a protruding portion facing surface facing the axial end surface of the magnet in the axial direction and the axial end surface of the magnet is a radial direction. A rotor that grows inward.   The rotor according to claim 1, further comprising an adhesive member between the protruding portion facing surface and the axial end surface.   3. At least one of the circumferential length of the upper protrusion and the circumferential length of the lower protrusion is longer than or equal to the circumferential length of the magnet. The rotor described in 1. The inner surface on the radially inner side of the rotor core includes a plurality of rotor core inner surfaces that are radially opposed to the magnet outer surface facing the radially outer side of each of the magnets,
The rotor according to any one of claims 1 to 3, wherein the magnet outer surface and the rotor core inner surface are planes parallel to each other.   The rotor according to any one of claims 1 to 4, wherein the rotor core further includes a convex portion protruding radially inward from an inner side surface on the radially inner side of the rotor core between the adjacent magnets.   6. The rotor according to claim 5, wherein an interval between a convex facing surface facing the magnet in the circumferential direction in the convex portion and a circumferential end surface facing the circumferential direction of the magnet increases as it goes radially inward. . A housing,
The housing is
A recess recessed in the axial direction to accommodate the rotor core;
In the recess, the rotor core is fixed, and has a cylindrical tube portion extending in the axial direction,
The cylindrical portion has a groove portion that is recessed radially outward and extends in the axial direction,
The rotor core further includes a protrusion that protrudes radially outward from an outer surface on the radially outer side,
The rotor according to any one of claims 1 to 6, wherein at least a part of the protrusion is inserted into the groove. A housing,
The housing is
A recess recessed in the axial direction to accommodate the rotor core;
In the recess, the rotor core is fixed, and has a cylindrical tube portion extending in the axial direction,
The cylindrical portion has a protruding portion that protrudes radially inward from an inner surface on the radially inner side,
The rotor core further has a groove that is recessed radially inward and extending in the axial direction on the outer surface on the radially outer side,
The rotor according to any one of claims 1 to 6, wherein at least a part of the protrusion is inserted into the groove. The rotor according to any one of claims 1 to 8, which is rotatable about the central axis;
And a stator that rotationally drives the rotor. A step in which a rotor core is formed by surrounding a central axis extending in the up-down direction in an annular shape and made of laminated steel;
A step of providing a plurality of magnets on the inner surface of the rotor core on the radially inner side,
The step of forming the rotor core includes:
A step in which a plurality of annular first steel plates are laminated in the axial direction;
Forming a second steel plate and a third steel plate having a radial distance from the inner end portion on the radially inner side to the central axis smaller than the first steel plate;
The second steel plate is laminated on the upper side in the axial direction of the first steel plate;
The third steel plate is laminated on the lower side in the axial direction of the first steel plate;
Have
In the step of providing the magnet, each of the magnets is provided between an inner end portion on the radially inner side of the second steel plate and an inner end portion on the radially inner side of the third steel plate,
In the step of forming the second steel plate and the third steel plate, the inner end portion in the radial direction of at least one of the second steel plate and the third steel plate is pressed by a jig having an inclined surface. The second surface is formed on the first surface facing the axial direction of the at least one steel plate, and the second surface faces the first surface in the axial direction as it goes radially inward. It is the surface that faces away from the direction,
The rotor manufacturing method in which the second surface is directed toward the first steel plate in the axial direction in at least one of the step of laminating the second steel plate and the step of laminating the third steel plate.

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