Motor and ceiling fan

Abstract

The present disclosure addresses the problem of inhibiting reduction in magnetic detection accuracy. A motor (M1) comprises: a stator (S1); and a first rotor that can rotate relative to the stator (S1). The first rotor has a permanent magnet in which different magnetic poles are alternately arranged along the rotation direction, and a support member that supports the permanent magnet. The stator (S1) has a plurality of electromagnets (1) arranged along the rotation direction of the first rotor, an attachment member (2) to which the electromagnets (1) are attached, and a magnetic detection unit (3) that detects magnetism of the permanent magnet. The electromagnets (1) each have a stator core (10) and a coil wound on the stator core (10). The magnetic detection unit (3) has Hall ICs (30) and a support substrate (31) that supports the Hall ICs (30). The Hall ICs (30) are disposed outside the stator cores (10) relative to the rotation center of the rotor.

Description

Motors and ceiling fans

[0001] The present disclosure relates to a motor and a ceiling fan, and more particularly to a so-called axial gap type motor and a ceiling fan powered by such a motor.

[0002] An example of a conventional example is an axial gap type rotating electric machine (motor) described in Patent Document 1. The axial gap type rotating electric machine described in Patent Document 1 (hereinafter referred to as the conventional example) includes a stator and a pair of rotors.

[0003] The stator includes a plurality of stator cores and a plurality of coils formed by winding conductive wires around each stator core. The plurality of stator cores are arranged at equal intervals around the circumferential direction of the rotating shaft.

[0004] The pair of rotors are attached to the rotating shaft so as to sandwich the stator in the axial direction of the rotating shaft. Each rotor includes a disk-shaped back yoke and a plurality of permanent magnets arranged on the back yoke's surface facing the stator. The permanent magnets are fixed to the back yoke so as to be arranged at equal intervals around the circumferential direction of the rotating shaft.

[0005] In the conventional example, when a magnetic field is generated by an electromagnet consisting of a stator core and a coil, this magnetic field influences the magnetic field generated by the permanent magnet, which generates attractive and repulsive forces between the electromagnet and the permanent magnet, causing the rotor to rotate.

[0006] Conventional brushless motors typically use Hall elements to detect the magnetic field (magnetic flux) of permanent magnets in order to determine the timing for passing excitation current through multiple electromagnets (coils). The Hall elements (or Hall ICs, which integrate Hall elements and signal processing circuits) are mounted on a printed wiring board and positioned so that they can detect the magnetism (magnetic flux) of the permanent magnets.

[0007] However, if the printed wiring board on which the Hall element is mounted bends due to the magnetic attraction force of the permanent magnet, the distance between the Hall element and the permanent magnet changes, which may reduce the accuracy of the Hall element's detection of magnetism (magnetic flux).

[0008] Japanese Patent Application Laid-Open No. 2017-175755

[0009] An object of the present disclosure is to provide a motor and a ceiling fan that can suppress a decrease in accuracy of magnetic detection.

[0010] A motor according to one aspect of the present disclosure includes a stator and a rotor rotatable relative to the stator. The rotor includes permanent magnets with different magnetic poles arranged alternately along the direction of rotation and a support member supporting the permanent magnets. The stator includes a plurality of electromagnets arranged along the direction of rotation of the rotor, a mounting member to which the electromagnets are attached, and a magnetic detection unit that detects the magnetism of the permanent magnets. Each of the electromagnets includes a stator core and a coil wound around the stator core. The magnetic detection unit includes a Hall element or a Hall IC and a support substrate that supports the Hall element or the Hall IC. The Hall element or the Hall IC is disposed outside the stator core with respect to the center of rotation of the rotor.

[0011] A ceiling fan according to one aspect of the present disclosure includes the motor and one or more blades that are driven to rotate by the motor.

[0012] FIG. 1 is an exploded perspective view of a motor according to an embodiment of the present disclosure. FIG. 2 is a perspective view of the motor, omitting the motor connector. FIG. 3 is a side view of the motor, omitting the motor connector. FIG. 4 is a perspective view of the motor, omitting the motor connector and second rotor. FIG. 5 is a perspective view of the motor, omitting the motor connector, second rotor, and mounting plate. FIG. 6 is a plan view of the motor, omitting the motor connector and support member. FIG. 7 is a plan view of the motor, omitting the motor connector, support member, and permanent magnet. FIG. 8 is a plan view of the main parts of the motor, omitting the motor connector, support member, and permanent magnet. FIG. 9 is an explanatory diagram for explaining the operation of the motor. FIG. 10 is an explanatory diagram for explaining the operation of the motor. FIG. 11 is a perspective view of a ceiling fan according to an embodiment of the present disclosure.

[0013] A motor and a ceiling fan according to an embodiment of the present disclosure will be described in detail below with reference to the drawings. However, the drawings described in the following embodiments are schematic diagrams, and the ratios of the sizes and thicknesses of the components do not necessarily reflect the actual dimensional ratios. Note that the configurations described in the following embodiments are merely examples of the present disclosure. The present disclosure is not limited to the following embodiments, and various modifications are possible depending on the design, etc., as long as the effects of the present disclosure can be achieved.

[0014] (1) Overview A motor M1 according to an embodiment of the present disclosure includes a stator S1 and a rotor (first rotor R1) that is rotatable relative to the stator S1 (see FIGS. 1 to 3). The first rotor R1 has permanent magnets 4 with different magnetic poles (magnetic pole portions 40) arranged alternately along the direction of rotation, and a support member 5 that supports the permanent magnets 4.

[0015] The stator S1 has a plurality of electromagnets 1 arranged along the rotation direction of the first rotor R1, a mounting member 2 to which the plurality of electromagnets 1 are attached, and a magnetic detection unit 3 that detects the magnetism of the permanent magnet 4.

[0016] Each of the electromagnets 1 has a stator core 10 and a coil 11 wound around the stator core 10. The magnetic detection unit 3 has a Hall element or Hall IC 30 and a support substrate 31 that supports the Hall IC 30. The Hall IC 30 is disposed outside the stator core 10 with respect to the center of rotation of the first rotor R1 (the center of the shaft 6) (see FIG. 7 ).

[0017] As will be described later, if the Hall element or Hall IC 30 is arranged inside the stator core 10 with respect to the center of rotation of the first rotor R1, the gap between the Hall element or Hall IC 30 and the permanent magnet 4 may widen due to deflection of the support substrate 31 supporting the Hall element or Hall IC 30, which may result in a decrease in the accuracy of magnetic detection by the magnetic detection unit 3.

[0018] In contrast, in the motor M1 according to this embodiment, the Hall elements or Hall ICs 30 are arranged outside the stator core 10 with respect to the center of rotation of the first rotor R1 (the center of the shaft 6). Therefore, the motor M1 according to this embodiment can suppress a decrease in accuracy of magnetic detection due to deflection of the support substrate 31, compared to when the Hall elements or Hall ICs 30 are arranged inside the stator core 10 with respect to the center of rotation of the first rotor R1.

[0019] Moreover, the ceiling fan CF1 according to the embodiment of the present disclosure includes a motor M1 according to the embodiment of the present disclosure and one or more blades 81 that are driven to rotate by the motor M1.

[0020] Therefore, since the ceiling fan CF1 according to the embodiment is equipped with the motor M1 according to the embodiment of the present disclosure, it is possible to suppress a decrease in accuracy of magnetic detection.

[0021] (2) Details of the Motor According to the Embodiment The motor M1 according to the embodiment (hereinafter referred to as motor M1) includes a rotor block and a stator S1. The motor M1 further includes a shaft 6 that rotatably supports the rotor block (see FIGS. 1 to 3). The shaft 6 is made of a metal material and has a hollow cylindrical shape.

[0022] (2-1) Rotor Block The rotor block has a first rotor R1, a second rotor R2, and a connector W1 that connects the first rotor R1 and the second rotor R2 (see FIG. 1).

[0023] (2-1-1) First Rotor The first rotor R1 has a permanent magnet 4 and a support member 5 that supports the permanent magnet 4. The permanent magnet 4 is, for example, a ring-shaped, double-sided, multi-pole neodymium magnet. That is, the permanent magnet 4 has multiple magnetic pole portions 40 that are magnetized with opposite poles (north and south poles) in the thickness direction. These multiple magnetic pole portions 40 have the same shape and dimensions and are arranged so that the opposite poles alternate along the circumferential direction of the permanent magnet 4 (see FIG. 1). Note that, although the number of magnetic pole portions 40 in the embodiment is 18, this is not limited thereto and may be 2 to 17 or 19 or more. Furthermore, the permanent magnet 4 may be a magnet other than a neodymium magnet, such as a ferrite magnet or a samarium-cobalt magnet.

[0024] The support member 5 has a bottom wall 50, a peripheral wall 51, a flange 52, and a housing portion 53 (see FIGS. 1 to 5). The bottom wall 50, the peripheral wall 51, the flange 52, and the housing portion 53 are preferably integrally formed from a soft magnetic material such as stainless steel.

[0025] The bottom wall 50 is formed in a disk shape. The peripheral wall 51 is formed in a cylindrical shape and protrudes from the periphery of the bottom wall 50 in the thickness direction of the bottom wall 50. The flange 52 is formed in a ring shape and protrudes outward from the tip of the peripheral wall 51. The accommodation portion 53 is formed in a cylindrical shape with a bottom. The accommodation portion 53 protrudes from the center of the bottom wall 50 along the thickness direction of the bottom wall 50 in the opposite direction to the peripheral wall 51 (downward in FIG. 1 ). A circular hole 530 penetrates the bottom of the accommodation portion 53 (see FIG. 1 ). Although not shown, a bearing is accommodated in the accommodation portion 53. The support member 5 (first rotor R1) is rotatably supported on the shaft 6 via a bearing accommodated in the accommodation portion 53.

[0026] The permanent magnet 4 is fixed to the bottom wall 50 by an appropriate method such as adhesive, welding, caulking, or screwing. In other words, the permanent magnet 4 is housed in a space surrounded by the bottom wall 50 and the peripheral wall 51 (see FIG. 2).

[0027] (2-1-2) Second Rotor The second rotor R2 has a top plate 70, a side plate 71, a flange 72, and a housing portion 73. The top plate 70, the side plate 71, the flange 72, and the housing portion 73 are preferably integrally formed from a soft magnetic material such as stainless steel.

[0028] The top plate 70 is formed in a disk shape. The side plate 71 is formed in a cylindrical shape and protrudes from the periphery of the top plate 70 in the thickness direction of the top plate 70. The flange 72 is formed in a ring shape and protrudes outward from the tip of the side plate 71. The accommodation portion 73 is formed in a cylindrical shape with a bottom. The accommodation portion 73 protrudes from the center of the top plate 70 along the thickness direction of the top plate 70 in the opposite direction to the side plate 71 (upward in FIG. 1 ). A circular hole 730 penetrates the bottom of the accommodation portion 73. Although not shown, a bearing is accommodated in the accommodation portion 73. The second rotor R2 is rotatably supported on the shaft 6 via a bearing accommodated in the accommodation portion 73.

[0029] (2-1-3) Connecting Body The connecting body W1 is cylindrical and made of a soft magnetic material such as stainless steel. A flange 52 of the support member 5 of the first rotor R1 is screwed (or riveted) to a first end face (the lower end face in FIG. 1 ) of the connecting body W1. Meanwhile, a flange 72 of the second rotor R2 is screwed (or riveted) to a second end face (the upper end face in FIG. 1 ) of the connecting body W1. In other words, the first rotor R1 (support member 5) and the second rotor R2 are connected by the connecting body W1 and can rotate integrally.

[0030] (2-2) Stator The stator S1 has a plurality of electromagnets 1 arranged along the rotation direction of the rotor block, a mounting member 2 to which the plurality of electromagnets 1 are attached, and a magnetic detection unit 3 that detects the magnetism of the permanent magnets 4.

[0031] (2-2-1) Electromagnets The multiple electromagnets 1 all have the same configuration. The number of the multiple electromagnets 1 is the same as the number of the multiple magnetic pole portions 40 of the permanent magnet 4 (18 pieces). However, the number of the electromagnets 1 does not have to be the same as the number of the magnetic pole portions 40.

[0032] The electromagnet 1 includes a stator core 10 , a coil 11 , and a bobbin 12 .

[0033] The stator core 10 has a first flange 101, a second flange 102, a fixed portion 103, and a body portion (see FIG. 5 ). The first flange 101 and the second flange 102 are each formed in a rectangular flat plate shape. The body portion is formed in a prismatic shape and connects the first flange 101 and the second flange 102. The fixed portion 103 is formed in a rectangular flat plate shape. The fixed portion 103 is joined to the second flange 102 such that a portion of the fixed portion 103 overlaps a portion of the second flange 102 in the thickness direction (see FIG. 5 ). Two protrusions 105 are provided on the surface of the fixed portion 103. These two protrusions 105 are formed in a quadrangular prism shape and protrude from the surface of the fixed portion 103 so as to be aligned parallel to each other. It is preferable that the first flange 101, the second flange 102, the fixed portion 103 and the body portion are integrally formed by stacking a plurality of laminated steel plates made of soft magnetic material such as electromagnetic steel plates in one direction.

[0034] The bobbin 12 has a cylindrical winding drum portion through which the drum portion of the stator core 10 is inserted, and a pair of flange portions 121 provided on both axial ends of the winding drum portion. The pair of flange portions 121 are formed in an oval shape and protrude outward, one from each axial end of the winding drum portion. The winding drum portion and the pair of flange portions 121 are preferably formed integrally from an electrically insulating material such as synthetic resin. However, the bobbin 12 is preferably composed of two parts in consideration of ease of assembly.

[0035] The coil 11 is formed by winding a wire made of aluminum or an aluminum alloy from the winding body of the bobbin 12 onto the body of the stator core 10 .

[0036] (2-2-2) Mounting Member The mounting member 2 has a mounting plate 20 , a plurality of fixing members 21 , and a reinforcing member 22 .

[0037] The mounting plate 20 is formed in a disk shape from a soft magnetic material such as stainless steel. A D-shaped insertion hole 200 penetrates the center of the mounting plate 20. The shaft 6 is inserted through this insertion hole 200. The mounting plate 20 also has a plurality of first mounting holes 201, a plurality of second mounting holes 202, and a plurality of third mounting holes 203 (see FIG. 1 ). The first mounting holes 201 are each circular and are arranged at equal intervals along the circumferential direction of the mounting plate 20 at both radial ends of the mounting plate 20. The second mounting holes 202 are each rectangular and are arranged at both radial ends of the mounting plate 20, inside the first mounting holes 201, along the circumferential direction of the mounting plate 20. The third mounting holes 203 are each circular and are arranged at equal intervals along the circumferential direction of the mounting plate 20, inside the second mounting holes 202, at both radial ends of the mounting plate 20.

[0038] The plurality of fixing members 21 all have the same configuration. The number of fixing members 21 is the same as the number of electromagnets 1 (18). However, the number of fixing members 21 does not have to be the same as the number of electromagnets 1.

[0039] The fixing member 21 is formed in a wedge shape from a non-magnetic material such as synthetic resin. A recess 210 is formed in a first surface (the surface facing the mounting plate 20) of the fixing member 21. Furthermore, at both ends of the longitudinal direction of the fixing member 21, one through-hole 211 is provided, and one through-hole 212 is provided at each end of the fixing member 21, penetrating the fixing member 21 in the height direction (see FIG. 5 ).

[0040] The reinforcing member 22 has a cylindrical main body 220, a tubular portion 221, and a plurality of rectangular pillar-shaped protrusions 222 (see FIGS. 1 and 5). The main body 220, the tubular portion 221, and the plurality of protrusions 222 are preferably integrally formed from a non-magnetic material such as synthetic resin or aluminum.

[0041] A D-shaped insertion hole penetrates the center of main body 220. Tube portion 221 protrudes from the periphery of the insertion hole in the first surface (the bottom surface in FIG. 1 ) of main body 220 in the normal direction of the first surface (the downward direction in FIG. 1 ). Note that tube portion 221 is formed in a cylindrical shape such that the cross section parallel to the first surface has the same shape as the insertion hole.

[0042] Each of the plurality of protrusions 222 protrudes from the first surface of the main body 220 in the same direction as the cylindrical portion 221. The plurality of protrusions 222 are arranged at equal intervals in the circumferential direction on both radial ends of the main body 220. Furthermore, a through-hole 224 is provided at the outer end of each of the protrusions 222, penetrating the protrusion 222 in the height direction (the up-and-down direction in FIG. 1 ) (see FIG. 5 ). The number of the plurality of protrusions 222 is the same as that of the electromagnet 1 (18 pieces), but it does not have to be the same number as that of the electromagnet 1.

[0043] Here, a plurality of grooves 223 are provided in the main body portion 220. The plurality of grooves 223 are arranged at equal intervals along the circumferential direction of the main body portion 220, straddling the second surface (the upper surface in FIG. 1 ) of the main body portion 220 and the side surface of the main body portion 220. Note that the tip portions of the plurality of fixing members 21 are fitted into each of the plurality of grooves 223 (see FIG. 5 ). In other words, the number of grooves 223 is the same as the number of fixing members 21 (18).

[0044] (2-2-3) Magnetic Detection Unit The magnetic detection unit 3 has a plurality of Hall ICs 30, a support substrate 31, and a holder 32 (see FIG. 1).

[0045] Each of the multiple (three in the illustrated example) Hall ICs 30 is configured by housing a Hall element for magnetic detection and a signal processing circuit in a single package. The signal processing circuit processes the output of the Hall element and outputs a detection signal. The detection signal output from the signal processing circuit (Hall IC 30) indicates the timing when the direction of the magnetic field (magnetic flux) of the permanent magnet 4 reverses as the rotor block rotates.

[0046] The support substrate 31 has a mounting portion 313, a protrusion 314, and a base portion 315. The mounting portion 313 is formed in the shape of a flat plate curved in an arc. The three Hall ICs 30 are mounted on a first surface 311 (the lower surface in FIG. 1 ) of the mounting portion 313 and are arranged at equal intervals along the circumferential direction (see FIG. 7 ).

[0047] The protruding portion 314 is formed in a narrow rectangular shape, and the tip of the protruding portion 314 is connected to the mounting portion 313.

[0048] The base portion 315 is formed in a rectangular shape that is much wider than the protruding portion 314. The base portion 315 is connected to the rear end of the protruding portion 314. A connector is mounted on the surface (top surface in FIG. 1 ) of the base portion 315. The connector is electrically connected to each Hall IC 30 via conductors (printed wiring) formed on the mounting portion 313, the protruding portion 314, and the base portion 315. In other words, a detection signal output from each Hall IC 30 is output to an external driving device (driver circuit) via the connector.

[0049] The holder 32 has a first support portion 321 that supports the mounting portion 313, a second support portion 322 that supports the protruding portion 314, a third support portion 323 that supports the base portion 315, and an attachment portion 324. The first support portion 321, the second support portion 322, the third support portion 323, and the attachment portion 324 are integrally formed from a non-magnetic material such as synthetic resin (see FIGS. 1, 5, and 7).

[0050] The first support portion 321 is formed in the shape of an arc-shaped frame, and supports the periphery of the mounting portion 313 of the support substrate 31 (see FIG. 5).

[0051] The second support portion 322 is formed in a long box shape. The tip of the second support portion 322 is connected to the first support portion 321. The second support portion 322 accommodates and supports the protrusion 314 of the support substrate 31 (see FIG. 5).

[0052] The third support portion 323 is formed in a rectangular box shape and is connected to the rear end of the second support portion 322. The third support portion 323 accommodates and supports the base portion 315 of the support substrate 31 (see FIG. 1).

[0053] The attachment portion 324 is formed in a disk shape with a circular hole 325 at the center thereof, and is connected to the rear end of the third support portion 323 (see FIGS. 1 and 7).

[0054] (2-3) Motor Assembly Procedure The assembly procedure for the above-mentioned motor M1 will be described. However, the assembly procedure described below is only an example, and the order of some steps may be changed, or other steps may be added.

[0055] (2-3-1) Assembling the Stator The worker first assembles the stator S1. The worker attaches the multiple electromagnets 1 to the mounting plate 20 by fitting the protrusions 105 of the stator core 10 one by one into the second mounting holes 202 of the mounting plate 20.

[0056] Next, the worker places the fixing members 21 one by one between the multiple electromagnets 1 attached to the mounting plate 20. At this time, parts of the stator cores 10 of two adjacent electromagnets 1 (part of the second flange portion 102 and part of the fixing portion 103) are housed in the recesses 210 of the fixing members 21 (see FIG. 5 ). Then, the worker inserts one rivet or screw into each of the two through holes 211, 212 of the fixing member 21 that overlaps with the first mounting hole 201 of the mounting plate 20, and fixes the multiple fixing members 21 to the mounting plate 20 with these rivets or screws.

[0057] Next, the worker places the reinforcing member 22 in the space surrounded by the multiple electromagnets 1 attached to the mounting plate 20. At this time, the worker fits the tip portions of the multiple fixing members 21 one by one into the multiple grooves 223 of the reinforcing member 22 (see FIG. 5 ). The worker then inserts one rivet or screw into each of the through holes 224 of the multiple protrusions 222 and the through holes 211 of each fixing member 21 that overlaps with each through hole 224, and fixes the reinforcing member 22 to the mounting plate 20 with the rivets or screws.

[0058] Next, the worker inserts the shaft 6 into the cylindrical portion 221 of the reinforcing member 22 and the insertion hole 200 of the mounting plate 20. Then, the worker fixes the reinforcing member 22 to the shaft 6 by screwing the cylindrical portion 221 and the shaft 6 together.

[0059] Next, the worker inserts the shaft 6 into the hole 325 of the attachment portion 324 in a direction such that the first support portion 321 of the holder 32 faces the electromagnet 1. Then, the worker fixes the attachment portion 324 of the holder 32 to the tip of the tubular portion 221 of the reinforcing member 22 by an appropriate method such as adhesive. As a result, the magnetic detection unit 3 is attached to the reinforcing member 22, and the assembly work of the stator S1 is completed.

[0060] (2-3-2) Assembling the Stator and Rotor Block Next, the worker rotatably attaches the first rotor R1 to the shaft 6 via the bearing housed in the housing portion 53 of the support member 5.

[0061] Next, the worker attaches the connecting body W1 to the flange 52 of the support member 5. Then, the worker rotatably attaches the second rotor R2 to the shaft 6 via the bearing housed in the housing portion 73.

[0062] Finally, the worker fixes the connector W1 to the flange 72 of the second rotor R2 and assembles the stator S1 to the rotor block, completing the assembly of the motor M1.

[0063] (2-4) Motor Operation The 18 electromagnets 1 are divided into three groups of six electromagnets 1. The electromagnets 1 belonging to different groups are arranged in order along the circumferential direction of the mounting member 2. The coils 11 of the six electromagnets 1 belonging to the same group are electrically connected in series, and the coils 11 of each group are three-phase star-connected. In other words, the three groups of electromagnets 1 are supplied with AC voltages (AC currents) of U-phase, V-phase, and W-phase, which are shifted in phase by 120 degrees each.

[0064] Based on the detection signal from the magnetic detection unit 3, the drive device controls the inverters connected to the three sets of electromagnets 1, and rotates the rotor block (first rotor R1) by switching the polarity of the electromagnets 1 belonging to each set.

[0065] (2-5) Advantages of the embodiment The holder 32 of the magnetic detection unit 3 supports the support substrate 31 in a cantilever manner. Therefore, the magnetic attraction force of the permanent magnet 4 acts on the Hall IC 30 mounted on the free end (mounting portion 313) of the support substrate 31, causing the magnetic detection unit 3 to bend.

[0066] 9 shows the position coordinates of the Hall IC 30 in a Cartesian coordinate system in which the axis of the shaft 6 is the origin O, the direction perpendicular to the axis is the X axis, and the direction of the axis is the Z axis. The X coordinate of the Hall IC 30 when no deflection occurs in the magnetic detection unit 3 (when the Z coordinate of the Hall IC 30 is 0) is set to X1. When deflection occurs in the magnetic detection unit 3 due to magnetic attraction (when the Z coordinate of the Hall IC 30 becomes greater than 0), the X coordinate of the Hall IC 30 changes from X1 to X2 (<X1). As a result, the Hall IC 30 is displaced in a direction approaching the axis of the shaft 6 (origin O).

[0067] Here, assume that the Hall IC 30 is disposed inside the electromagnet 1 (stator core 10) (closer to the shaft 6 than the electromagnet 1 in the radial direction of the mounting member 2). In this case, the Hall IC 30 is displaced in a direction approaching the axis of the shaft 6, which increases the distance between the Hall IC 30 and the permanent magnet 4 in a direction perpendicular to the axis (radial direction of the mounting member 2). The solid line α1 in Figure 10 shows the change in the magnetic field (magnetic flux density) that intersects with the Hall IC when there is no deflection in the magnetic detection unit 3. As the magnetic pole portion 40 of the permanent magnet 4 attached to the first rotor R1 moves in the circumferential direction, the magnetic flux density that intersects with the Hall IC changes monotonically (see solid line α1).

[0068] On the other hand, the solid line α2 in Fig. 10 shows the change in magnetic flux density when bending occurs in the magnetic detection unit 3, indicating that the magnetic flux density crossing the Hall IC does not change monotonically but repeatedly increases and decreases. Note that the symbol "Th" in Fig. 10 indicates the threshold value used by the Hall IC to determine switching of the magnetic field (magnetic flux density). In other words, as shown by the solid line α2 in Fig. 10, when bending occurs in the magnetic detection unit 3, the detection accuracy of the magnetic detection unit 3 decreases.

[0069] However, in the motor M1, the Hall IC 30 is disposed outside the stator core 10 with respect to the center of rotation of the first rotor R1 (the axis of the shaft 6). Therefore, when the magnetic detection unit 3 is deflected and the Hall IC 30 is displaced in a direction approaching the axis of the shaft 6, the distance between the Hall IC 30 and the permanent magnet 4 in the direction perpendicular to the axis becomes shorter. Therefore, in the motor M1, the magnetic field (magnetic flux density) detected by the Hall IC 30 of the magnetic detection unit 3 changes monotonically, and it is possible to suppress a decrease in the accuracy of magnetic detection due to deflection of the magnetic detection unit 3.

[0070] Furthermore, in the magnetic detection unit 3, the Hall IC 30 is mounted on the first surface 311 of the support substrate 31, i.e., the surface facing the permanent magnet 4 attached to the first rotor R1 (see FIG. 3 ). Therefore, in the motor M1, the distance between the Hall IC 30 and the permanent magnet 4 is smaller when the magnetic detection unit 3 is bent, compared to when the Hall IC 30 is mounted on the second surface 312 of the support substrate 31. As a result, the motor M1 can further suppress a decrease in magnetic detection accuracy.

[0071] Furthermore, in the magnetic detection unit 3, the support substrate 31 has a mounting portion 313 on which the Hall IC 30 is mounted and a protrusion 314 that protrudes from the mounting portion 313 toward the center of rotation. That is, in the motor M1, the support substrate 31 can be attached to the stator S1 via the protrusion 314 that protrudes from the mounting portion 313, rather than via the mounting portion 313 on which the Hall IC 30 is mounted. Therefore, in the motor M1, the support substrate 31 can be accommodated within the height of the stator core 10, and the stator S1 can be made low-profile (flattened).

[0072] Here, the protrusion 314 of the support substrate 31 is formed with wiring (conductors) for electrically connecting the Hall IC 30 and the drive device. If the current flowing through the wiring of the protrusion 314 is affected by the magnetic field of the electromagnet 1, this could result in a decrease in the detection accuracy of the magnetic detection unit 3. In contrast, the motor M1 has the protrusion 314 disposed between two adjacent electromagnets 1 in the rotation direction among the multiple electromagnets 1, and the width d1 of the protrusion 314 is set to be equal to or smaller than the distance d2 between the stator cores 10 of the two electromagnets 1 (see FIG. 8 ). This allows the support substrate 31 of the motor M1 to be contained within the height of the stator core 10, thereby enabling the stator S1 to be further reduced in height (flattened).

[0073] Furthermore, the distance r2 from the center of rotation (the axis of the shaft 6) to the outermost periphery of the support substrate 31 is equal to or less than the distance r1 from the center of rotation to the inner periphery of the rotors (the first rotor R1 and the second rotor R2) (see FIG. 7 ). That is, the motor M1 does not allow the support substrate 31 to protrude outside the mounting plate 20 of the first rotor R1, thereby reducing the risk of contact between the support substrate 31 and the first rotor R1 and preventing a decrease in detection accuracy due to the Hall IC 30 being too far away from the permanent magnet 4.

[0074] Furthermore, the motor M1 is a so-called double-rotor axial gap motor with a single-sided magnet, which includes a second rotor R2 that faces the first rotor R1 across the stator S1 and is connected to the first rotor R1. Double-rotor axial gap motors are generally double-sided magnet motors, with permanent magnets mounted on each of the two rotors. However, the motor M1 has a permanent magnet 4 only on the first rotor R1, and no permanent magnet on the second rotor R2.

[0075] Therefore, since the motor M1 has a permanent magnet 4 on only one rotor (the first rotor R1), manufacturing costs can be reduced compared to when permanent magnets are provided on both rotors. Furthermore, because the motor M1 is a double-rotor type, it has the advantage of being able to suppress wobbling when rotating an object (such as the blades 81 of the ceiling fan CF1) compared to a single-rotor type.

[0076] (3) Details of the ceiling fan according to the embodiment The ceiling fan CF1 according to the embodiment (hereinafter referred to as ceiling fan CF1) comprises, as shown in FIG. 11, a main body 80 incorporating a motor M1, and multiple (four in the illustrated example) blades 81 that are rotated by the motor M1.

[0077] The main body 80 is formed into a cylindrical shape from metal or synthetic resin. The main body 80 is mechanically and electrically detachably attached to, for example, a ceiling hook body installed on a room's ceiling. The main body 80 houses the motor M1 so that the axis of the shaft 6 is perpendicular to the ceiling surface.

[0078] Each of the four blades 81 is made of synthetic resin and has the same shape and dimensions. The base of each blade 81 is fixed to, for example, the connector W1 of the motor M1. In other words, when the rotor block of the motor M1 rotates, the four blades 81 fixed to the rotor block (connector W1) also rotate.

[0079] Therefore, the ceiling fan CF1 rotates the blades 81 using the motor M1 according to the embodiment, and thus, like the motor M1, it is possible to suppress a decrease in the detection accuracy of the magnetic detection unit 3.

[0080] (4) Summary A motor (M1) according to a first aspect of the present disclosure includes a stator (S1) and a rotor (first rotor R1) rotatable relative to the stator (S1). The rotor includes permanent magnets (4) with different magnetic poles arranged alternately along the direction of rotation, and a support member (5) supporting the permanent magnets (4). The stator (S1) includes a plurality of electromagnets (1) arranged along the direction of rotation of the rotor, a mounting member (2) to which the plurality of electromagnets (1) are attached, and a magnetic detection unit (3) that detects the magnetism of the permanent magnets (4). Each of the plurality of electromagnets (1) includes a stator core (10) and a coil (11) wound around the stator core (10). The magnetic detection unit (3) includes a Hall element or Hall IC (30) and a support substrate (31) that supports the Hall element or Hall IC (30). The Hall element or Hall IC (30) is arranged outside the stator core (10) with respect to the center of rotation of the rotor.

[0081] In the motor (M1) according to the first aspect, even if the support substrate (31) is bent, the distance between the Hall element or Hall IC (30) and the permanent magnet (4) is unlikely to increase, so that it is possible to suppress a decrease in the accuracy of magnetic detection due to bending of the support substrate (31).

[0082] A motor (M1) according to a second aspect of the present disclosure can be realized by combining it with the first aspect. In the motor (M1) according to the second aspect, the support substrate (31) preferably has a first surface (311) facing the rotor and a second surface (312) facing the mounting member (2). The Hall element or Hall IC (30) is preferably supported on the first surface (311) of the support substrate (31).

[0083] The motor (M1) according to the second aspect can further suppress the decrease in accuracy of magnetic detection.

[0084] A motor (M1) according to a third aspect of the present disclosure can be realized by combining it with the first or second aspect. In the motor (M1) according to the third aspect, the support substrate (31) preferably has a mounting portion (313) on which the Hall element or Hall IC (30) is mounted, and a protruding portion (314) protruding from the mounting portion (313) toward the center of rotation.

[0085] In the motor (M1) according to the third aspect, the stator (S1) can be made low-profile (flat).

[0086] A motor (M1) according to a fourth aspect of the present disclosure can be realized in combination with the third aspect. In the motor (M1) according to the fourth aspect, the protrusion (314) is preferably disposed between two adjacent electromagnets (1) in the rotation direction among the plurality of electromagnets (1). The width (d1) of the protrusion (314) is preferably equal to or less than the distance (d2) between the stator cores (10) of the two electromagnets (1).

[0087] In the motor (M1) according to the fourth aspect, the stator (S1) can be made even lower in height (flatter).

[0088] A motor (M1) according to a fifth aspect of the present disclosure can be realized by combining it with any one of aspects 1 to 4. In the motor (M1) according to the fifth aspect, it is preferable that the distance (r2) from the center of rotation to the outermost periphery of the support substrate (31) is equal to or less than the distance (r1) from the center of rotation to the inner periphery of the rotor.

[0089] In the motor (M1) according to the fifth aspect, the support substrate (31) does not protrude outside the rotor, thereby reducing the risk of contact between the support substrate (31) and the rotor, and preventing the Hall element or Hall IC (30) from being too far away from the permanent magnet (4), resulting in a decrease in detection accuracy.

[0090] A motor (M1) according to a sixth aspect of the present disclosure can be realized by combining it with any of the first to fifth aspects. In the motor (M1) according to the sixth aspect, it is preferable that the rotor is a first rotor (R1). It is preferable that the motor (M1) according to the sixth aspect further includes a second rotor (R2) that faces the first rotor (R1) across the stator (S1) and is connected to the first rotor (R1). It is preferable that the second rotor (R2) does not have a permanent magnet.

[0091] The motor (M1) according to the sixth aspect can reduce manufacturing costs.

[0092] A ceiling fan (CF1) according to a seventh aspect of the present disclosure comprises a motor (M1) according to any one of the first to sixth aspects and one or more blades (81) that are driven to rotate by the motor (M1).

[0093] The ceiling fan (CF1) according to the seventh aspect is equipped with the motor (M1) according to any one of the first to sixth aspects, and therefore is able to suppress a decrease in accuracy of magnetic detection.

[0094] M1 Motor CF1 Ceiling fan S1 Stator R1 First rotor (rotor) R2 Second rotor 1 Electromagnet 2 Mounting member 3 Magnetic detection unit 4 Permanent magnet 5 Support member 10 Stator core 11 Coil 30 Hall IC 31 Support substrate 80 Main body 81 Blade 311 First surface 312 Second surface 313 Mounting portion 314 Protrusion

Claims

1. A stator; a rotor rotatable relative to the stator; Equipped with The rotor is A permanent magnet with different magnetic poles arranged alternately along the direction of rotation; A support member for supporting the permanent magnet; having The stator includes: A plurality of electromagnets arranged along the rotation direction of the rotor; a mounting member to which the plurality of electromagnets are attached; A magnetic detection unit that detects the magnetism of the permanent magnet; having Each of the plurality of electromagnets comprises: A stator core; A coil wound around the stator core; having The magnetic detection unit includes: A Hall element or a Hall IC; a support substrate supporting the Hall element or the Hall IC; having the Hall element or the Hall IC is disposed outside the stator core with respect to the center of rotation of the rotor; Motor.

2. the support substrate has a first surface facing the rotor and a second surface facing the mounting member, The Hall element or the Hall IC is supported on the first surface of the supporting substrate. The motor according to claim 1.

3. The supporting substrate has a mounting portion on which the Hall element or the Hall IC is mounted, and a protruding portion protruding from the mounting portion toward the rotation center.

3. The motor according to claim 1 or 2.

4. the protrusion is disposed between two electromagnets adjacent to each other along the rotation direction among the plurality of electromagnets, The width of the protrusion is equal to or smaller than the distance between the stator cores of the two electromagnets. The motor according to claim 3.

5. a distance from the rotation center to an outermost periphery of the support substrate is equal to or less than a distance from the rotation center to an inner periphery of the rotor; 3. The motor according to claim 1 or 2.

6. The rotor is a first rotor, a second rotor that faces the first rotor across the stator and is connected to the first rotor, the second rotor does not have a permanent magnet; 3. The motor according to claim 1 or 2.

7. A motor according to claim 1 or 2; one or more blades that are driven to rotate by the motor; Equipped with Ceiling fan.