Motors and ceiling fans

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

Technical Field

[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 using the motor as a power source.

Background Art

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

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

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

[0005] In the conventional example, when a magnetic field is formed by an electromagnet composed of a stator core and a coil, the magnetic field affects the magnetic field generated from the permanent magnet. As a result, in the conventional example, attractive and repulsive forces are generated between the electromagnet and the permanent magnet to rotate the rotor.

[0006] By the way, a brushless motor such as the conventional example usually uses a Hall element to detect the magnetic field (magnetic flux) of a permanent magnet in order to determine the timing of flowing an exciting current through a plurality of electromagnets (coils). The Hall element (or a Hall IC in which a Hall element and a circuit for signal processing are integrated) is mounted on a printed wiring board and arranged at a position where the magnetism (magnetic flux) of the permanent magnet can be detected.

[0007] However, if the printed circuit board on which the Hall element is mounted flexes due to the magnetic attraction 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). [Prior art documents] [Patent Documents]

[0008] [Patent Document 1] Japanese Patent Publication No. 2017-175755 [Overview of the project]

[0009] The purpose of this disclosure is to provide a motor and a ceiling fan that can suppress the decrease in accuracy of magnetic detection.

[0010] A motor according to one aspect of the present disclosure comprises a stator and a rotor rotatable relative to the stator. The rotor has permanent magnets with alternating magnetic poles along the direction of rotation and a support member for supporting the permanent magnets. The stator has a plurality of electromagnets arranged along the direction of rotation of the rotor, a mounting member to which the plurality of electromagnets are attached, and a magnetic detection unit for detecting the magnetism of the permanent magnets. Each of the plurality of electromagnets has a stator core and a coil wound around the stator core. The magnetic detection unit has a Hall element or Hall IC and a support substrate for supporting the Hall element or Hall IC. The Hall element or Hall IC is positioned outside the stator core with respect to the rotation center of the rotor. The support substrate has a mounting portion on which the Hall element or the Hall IC is mounted, and a projection that protrudes from the mounting portion toward the center of rotation. The projection is positioned between two adjacent electromagnets among the plurality of electromagnets along the direction of rotation. The width of the projection is less than or equal to the distance between the stator cores of the two electromagnets.

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

[0012] [Figure 1] Figure 1 is an exploded perspective view of a motor according to an embodiment of this disclosure. [Figure 2]Figure 2 is a perspective view of the same motor with the coupling assembly omitted. [Figure 3] Figure 3 is a side view of the motor shown above, with the coupling assembly omitted. [Figure 4] Figure 4 is a perspective view of the same motor, with the coupling and second rotor omitted. [Figure 5] Figure 5 is a perspective view of the motor shown above, with the coupling body, second rotor, and mounting plate omitted. [Figure 6] Figure 6 is a plan view of the motor shown above, with the connecting body and support members omitted. [Figure 7] Figure 7 is a plan view of the motor shown above, with the connecting body, support members, and permanent magnets omitted. [Figure 8] Figure 8 is a plan view of the main components of the motor shown above, with the connecting body, support members, and permanent magnets omitted. [Figure 9] Figure 9 is an explanatory diagram illustrating the operation of the motor shown above. [Figure 10] Figure 10 is an explanatory diagram illustrating the operation of the motor shown above. [Figure 11] Figure 11 is a perspective view of a ceiling fan according to an embodiment of this disclosure. [Modes for carrying out the invention]

[0013] Hereinafter, the motor and ceiling fan according to the embodiments of this disclosure will be described in detail with reference to the drawings. However, the figures described in the embodiments below are schematic diagrams, and the ratios of the size and thickness of each component do not necessarily reflect the actual dimensional ratios. Furthermore, the configurations described in the embodiments below are merely examples of this disclosure. This disclosure is not limited to the embodiments below, and various modifications are possible depending on the design, etc., as long as the effects of this disclosure can be achieved.

[0014] (1) Overview The motor M1 according to an embodiment of the present disclosure includes a stator S1 and a rotor (first rotor R1) rotatable with respect to the stator S1 (see FIGS. 1-3). The first rotor R1 has a permanent magnet 4 in which different magnetic poles (magnetic pole portions 40) are alternately arranged along the rotation direction, and a support member 5 that supports the permanent magnet 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 plurality of 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 rotation center of the first rotor R1 (center of the shaft 6) (see FIG. 7).

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

[0018] In contrast, the motor M1 according to the embodiment disposes the Hall element or Hall IC 30 outside the stator core 10 with respect to the rotation center of the first rotor R1 (center of the shaft 6). Therefore, the motor M1 according to the embodiment can suppress a decrease in the accuracy of magnetic detection due to the deflection of the support substrate 31 compared to the case where the Hall element or Hall IC 30 is disposed inside the stator core 10 with respect to the rotation center of the first rotor R1.

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

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

[0021] (2) Details of the motor according to the embodiment The motor M1 according to this embodiment (hereinafter referred to as motor M1) comprises a rotor block and a stator S1. The motor M1 further comprises a shaft 6 that rotatably supports the rotor block (see Figures 1-3). The shaft 6 is formed in a hollow cylindrical shape from a metal material.

[0022] (2-1) Rotor Block The rotor block comprises a first rotor R1, a second rotor R2, and a connecting body W1 that connects the first rotor R1 and the second rotor R2 (see Figure 1).

[0023] (2-1-1) First rotor The first rotor R1 includes 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 a plurality of magnetic pole portions 40 that are magnetized with opposite poles (N pole and S pole) in the thickness direction. These plurality of magnetic pole portions 40 are the same shape and the same dimensions, and are arranged so that the opposite poles are alternately arranged along the circumferential direction of the permanent magnet 4 (see Figure 1). In this embodiment, the number of magnetic pole portions 40 is 18, but is not limited to this, and may be 2 to 17 or 19 or more. Also, the permanent magnet 4 may be a magnet other than a neodymium magnet, for example, 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 Figures 1-5). Preferably, the bottom wall 50, peripheral wall 51, flange 52, and housing portion 53 are integrally formed from a soft magnetic material such as stainless steel.

[0025] The bottom wall 50 is formed in a disc 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 housing portion 53 is formed in a bottomed cylindrical shape. The housing portion 53 protrudes from the center of the bottom wall 50 in the opposite direction to the peripheral wall 51 (downward in Figure 1) along the thickness direction of the bottom wall 50. A circular hole 530 passes through the bottom of the housing portion 53 (see Figure 1). Although not shown, a bearing is housed in the housing portion 53. The support member 5 (first rotor R1) is rotatably supported on the shaft 6 via a bearing housed in the housing portion 53.

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

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

[0028] The top plate 70 is formed in a disc shape. The side plates 71 are formed in a cylindrical shape and protrude from the periphery of the top plate 70 in the direction of the thickness 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 housing portion 73 is formed in a bottomed cylindrical shape. The housing portion 73 protrudes from the center of the top plate 70 in the direction opposite to that of the side plates 71 (upward in Figure 1) along the direction of the thickness of the top plate 70. A circular hole 730 passes through the bottom of the housing portion 73. Although not shown in the illustration, a bearing is housed in the housing portion 73. The second rotor R2 is rotatably supported on the shaft 6 via a bearing housed in the housing portion 73.

[0029] (2-1-3) Concatenated body The connecting body W1 is formed in a cylindrical shape from a soft magnetic material such as stainless steel. The flange 52 of the support member 5 for the first rotor R1 is screwed (or riveted) to the first end face of the connecting body W1 (the lower end face in Figure 1). On the other hand, the flange 72 of the second rotor R2 is screwed (or riveted) to the second end face of the connecting body W1 (the upper end face in Figure 1). 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 as a single unit.

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

[0031] (2-2-1) Electromagnet All of the electromagnets 1 have the same configuration. The number of electromagnets 1 is the same as the number of magnetic poles 40 of the permanent magnet 4 (18). However, the number of electromagnets 1 does not have to be the same as the number of magnetic poles 40.

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

[0033] The stator core 10 has a first flange portion 101, a second flange portion 102, a fixing portion 103, and a body portion (see Figure 5). The first flange portion 101 and the second flange portion 102 are each formed in the shape of a rectangular flat plate. The body portion is formed in the shape of a rectangular prism and connects the first flange portion 101 and the second flange portion 102. The fixing portion 103 is formed in the shape of a rectangular flat plate. The fixing portion 103 is connected to the second flange portion 102 by overlapping a part of it with a part of the second flange portion 102 in the thickness direction (see Figure 5). Two protrusions 105 are provided on the surface of the fixing portion 103. These two protrusions 105 are formed in the shape of a rectangular prism and protrude from the surface of the fixing portion 103 so as to be parallel to each other. Furthermore, it is preferable that the first flange portion 101, the second flange portion 102, the fixing portion 103, and the body portion are integrally formed by laminating multiple laminated steel sheets made of a soft magnetic material such as electromagnetic steel sheets in one direction.

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

[0035] The coil 11 is constructed by winding an aluminum or aluminum alloy wire around the body of the stator core 10 from the winding drum of the bobbin 12.

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

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

[0038] All of the fixing members 21 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 on the first surface of the fixing member 21 (the surface facing the mounting plate 20). In addition, one through hole 211 and 212 are provided at each end of the fixing member 21 in the longitudinal direction, penetrating through the fixing member 21 in the height direction (see Figure 5).

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

[0041] A D-shaped through-hole penetrates the center of the main body portion 220. The cylindrical portion 221 protrudes from the periphery of the through-hole on the first surface (bottom surface in Figure 1) of the main body portion 220 in the direction normal to the first surface (downward in Figure 1). The cylindrical portion 221 is formed in a cylindrical shape with a cross-sectional shape parallel to the first surface that is the same as that of the through-hole.

[0042] Each of the multiple protrusions 222 projects from the first surface of the main body 220 in the same direction as the cylindrical portion 221. Furthermore, the multiple protrusions 222 are arranged at equal intervals in the circumferential direction at both radial ends of the main body 220. In addition, a through hole 224 is provided at the outer end of each protrusion 222, penetrating the protrusion 222 in the height direction (up and down direction in Figure 1) (see Figure 5). Note that the number of multiple protrusions 222 is the same as the number of electromagnets 1 (18), but the number does not have to be the same as the number of electromagnets 1.

[0043] Here, the main body portion 220 is provided with multiple grooves 223. The multiple grooves 223 span the second surface (top surface in Figure 1) and the side surface of the main body portion 220, and are arranged at equal intervals along the circumferential direction of the main body portion 220. One tip portion of the multiple fixing members 21 is fitted into each of the multiple grooves 223 (see Figure 5). In other words, the number of multiple 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 includes a plurality of Hall ICs 30, a support substrate 31, and a holder 32 (see Figure 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 to output 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 protruding portion 314, and a base portion 315. The mounting portion 313 is formed in the shape of a flat plate that is curved in an arc. Three Hole ICs 30 are mounted on the first surface 311 of the mounting portion 313 (the lower surface in Figure 1) at equal intervals along the circumferential direction (see Figure 7).

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

[0048] The base portion 315 is formed in a quadrangular shape that is sufficiently 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 of the base portion 315 (the top surface in Figure 1). The connector is electrically connected to each hole IC 30 via conductors (printed wiring) formed on the mounting portion 313, the protruding portion 314, and the base portion 315. In other words, the detection signals output from each hole IC 30 are output to an external drive device (driver circuit) via the connector.

[0049] The holder 32 includes 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 a mounting portion 324. The first support portion 321, the second support portion 322, the third support portion 323, and the mounting portion 324 are integrally formed from a non-magnetic material such as synthetic resin (see Figures 1, 5, and 7).

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

[0051] The second support portion 322 is formed in a long, box-like 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 protruding portion 314 of the support substrate 31 (see Figure 5).

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

[0053] The mounting portion 324 is formed in the shape of a disc with a circular hole 325 passing through its center. The mounting portion 324 is connected to the rear end of the third support portion 323 (see Figures 1 and 7).

[0054] (2-3) Motor assembly procedure The assembly procedure for the motor M1 described above is explained below. However, the assembly procedure described below is just one example, and you may change the order of some of the steps or add other steps.

[0055] (2-3-1) Stator assembly The worker first assembles the stator S1. The worker then attaches 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 one fixing member 21 between each of the multiple electromagnets 1 attached to the mounting plate 20. At this time, a portion of the stator core 10 of two adjacent electromagnets 1 (a portion of the second flange portion 102 and a portion of the fixing portion 103) is accommodated in the recess 210 of the fixing member 21 (see Figure 5). Then, the worker inserts one rivet or screw into each of the two through holes 211 and 212 of the fixing member 21, the through hole 212 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 into the space surrounded by the multiple electromagnets 1 attached to the mounting plate 20. At this time, the worker fits the tips of the multiple fixing members 21 one by one into the multiple grooves 223 of the reinforcing member 22 (see Figure 5). Then, the worker inserts one rivet or screw through each of the through holes 224 of the multiple protrusions 222 and through the through holes 211 of each fixing member 21 that overlap with each through hole 224, and fixes the reinforcing member 22 to the mounting plate 20 with these rivets or screws.

[0058] Next, the worker inserts the shaft 6 through 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 through the hole 325 of the mounting portion 324 with the first support portion 321 of the holder 32 facing the electromagnet 1. Then, the worker fixes the mounting portion 324 of the holder 32 and the tip of the cylindrical 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 of the stator S1 is completed.

[0060] (2-3-2) Assembly of 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 section 73.

[0062] Finally, the worker secures 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. The electromagnets 1 belonging to different groups are arranged sequentially 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 connected in a three-phase star configuration. In other words, the three groups of electromagnets 1 are each supplied with separate AC voltages (AC currents) of the U, V, and W phases, which are shifted in phase by 120 degrees.

[0064] The drive unit controls inverters connected to three sets of electromagnets 1 based on the detection signal from the magnetic detection unit 3, 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 cantilever-supports the support substrate 31. As a result, 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] FIG. 9 shows the position coordinates of the Hall IC 30 in a rectangular coordinate system with the axis of the shaft 6 as the origin O, the direction orthogonal to the axis as the X-axis, and the direction of the axis as the Z-axis. Let X1 be the X coordinate of the Hall IC 30 when there is no deflection in the magnetic detection unit 3 (when the Z coordinate of the Hall IC 30 is 0). When deflection occurs in the magnetic detection unit 3 due to the magnetic attraction force (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 a case where the Hall IC 30 is disposed inside the electromagnet 1 (on the side closer to the shaft 6 than the electromagnet 1 in the radial direction of the mounting member 2). In this case, when 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 increases in the direction orthogonal to the axis (radial direction of the mounting member 2). The solid line α1 in FIG. 10 shows the change in the magnetic field (magnetic flux density) intersecting 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 intersecting the Hall IC changes monotonically (see the solid line α1).

[0068] On the other hand, the solid line α2 in FIG. 10 shows the change in the magnetic flux density when there is deflection in the magnetic detection unit 3, indicating that the magnetic flux density intersecting the Hall IC does not change monotonically but repeats increases and decreases. The symbol “Th” in FIG. 10 indicates the threshold value for the Hall IC to determine the switching of the magnetic field (magnetic flux density). That is, as shown by the solid line α2 in FIG. 10, when deflection occurs in the magnetic detection unit 3, the detection accuracy of the magnetic detection unit 3 decreases.

[0069] However, in motor M1, the Hall IC 30 is positioned outside the stator core 10 with respect to the rotation center of the first rotor R1 (the axis of the shaft 6). Therefore, if the magnetic detection unit 3 deflects and the Hall IC 30 is displaced in a direction closer to the axis of the shaft 6, the distance between the Hall IC 30 and the permanent magnet 4 in a direction perpendicular to the axis becomes shorter. Consequently, in motor M1, the magnetic field (magnetic flux density) detected by the Hall IC 30 of the magnetic detection unit 3 changes monotonically, thus suppressing the decrease in magnetic detection accuracy 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, that is, the surface facing the permanent magnet 4 attached to the first rotor R1 (see Figure 3). Therefore, compared to the case where the Hall IC 30 is mounted on the second surface 312 of the support substrate 31, the distance between the Hall IC 30 and the permanent magnet 4 is smaller when the magnetic detection unit 3 is deflected. As a result, the motor M1 can further suppress the 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 protruding portion 314 that protrudes from the mounting portion 313 toward the center of rotation. In other words, the motor M1 can attach the support substrate 31 to the stator S1 not by the mounting portion 313 on which the Hall IC 30 is mounted, but by the protruding portion 314 that protrudes from the mounting portion 313. As a result, the motor M1 can fit the support substrate 31 within the height of the stator core 10, thereby enabling a lower profile (flatter design) of the stator S1.

[0072] Here, the protruding portion 314 of the support substrate 31 has wiring (conductors) formed on it for electrically connecting the Hall IC 30 and the drive unit. However, if the current flowing through the wiring of the protruding portion 314 is affected by the magnetic field of the electromagnet 1, it may lead to a decrease in the detection accuracy of the magnetic detection unit 3. In response to this, the motor M1 positions the protruding portion 314 between two electromagnets 1 that are adjacent to each other in the direction of rotation, and sets the width d1 of the protruding portion 314 to be less than or equal to the distance d2 between the stator cores 10 of the two electromagnets 1 (see Figure 8). As a result, the motor M1 can house the support substrate 31 within the height of the stator core 10, thus enabling further reduction in the height (flattening) of the stator S1.

[0073] Furthermore, the distance r2 from the center of rotation (the axis of the shaft 6) to the outermost circumference of the support substrate 31 is less than or equal to the distance r1 from the center of rotation to the inner circumference of the rotor (the first rotor R1 and the second rotor R2) (see Figure 7). In other words, 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 the Hall IC 30 from moving too far away from the permanent magnet 4, which would reduce the detection accuracy.

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

[0075] However, since motor M1 has permanent magnets 4 on only one rotor (first rotor R1), it is possible to reduce manufacturing costs compared to the case where permanent magnets are on both rotors. In addition, since motor M1 is a double-rotor type, it has advantages over single-rotor types such as being able to suppress wobbling when rotating an object (such as the blades 81 of ceiling fan CF1).

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

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

[0078] Each of the four blades 81 is formed from synthetic resin to have the same shape and dimensions. The base of each blade 81 is fixed, for example, to the connecting body W1 of the motor M1. In other words, as the rotor block of the motor M1 rotates, the four blades 81 fixed to the rotor block (connecting body W1) also rotate.

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

[0080] (4) Summary A motor (M1) according to a first aspect of the present disclosure comprises a stator (S1) and a rotor (first rotor R1) rotatable relative to the stator (S1). The rotor has permanent magnets (4) with different magnetic poles arranged alternately along the direction of rotation and a support member (5) that supports the permanent magnets (4). The stator (S1) has 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) 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 element or Hall IC (30). The Hall element or Hall IC (30) is positioned outside the stator core (10) with respect to the rotation center of the rotor.

[0081] In the motor (M1) according to the first embodiment, even if the support substrate (31) is deflected, the distance between the Hall element or Hall IC (30) and the permanent magnet (4) does not increase easily, thus suppressing a decrease in the accuracy of magnetic detection due to the deflection of the support substrate (31).

[0082] A motor (M1) according to a second aspect of this 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 embodiment can further suppress the decrease in accuracy of magnetic detection.

[0084] A motor (M1) according to a third aspect of this 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 a Hall element or Hall IC (30) is mounted, and a projection (314) that protrudes from the mounting portion (313) toward the center of rotation.

[0085] The motor (M1) according to the third embodiment allows for a lower profile (flattening) of the stator (S1).

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

[0087] The motor (M1) according to the fourth embodiment allows for further reduction in the height (flattening) of the stator (S1).

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

[0089] The motor (M1) according to the fifth embodiment does not allow the support substrate (31) to 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 moving too far away from the permanent magnet (4) and reducing the detection accuracy.

[0090] A motor (M1) according to a sixth aspect of this disclosure can be realized by combination 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). The motor (M1) according to the sixth aspect further preferably comprises a second rotor (R2) which faces the first rotor (R1) across a stator (S1) and is connected to the first rotor (R1). It is preferable that the second rotor (R2) does not have permanent magnets.

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

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

[0093] The ceiling fan (CF1) according to the seventh embodiment is equipped with a motor (M1) according to any of the first to sixth embodiments, so that a decrease in the accuracy of magnetic detection can be suppressed. [Explanation of Symbols]

[0094] M1 Motor CF1 Ceiling Fan S1 Stator R1 First rotor (rotor) R2 Second Rotor 1. Electromagnet 2. Mounting components 3. Magnetic detection unit 4 Permanent Magnets 5. Support Member 10 Stator Cores 11 coils 30 Hole IC 31 Support substrate 80 Main Unit 81 feathers 311 Page 1 312 2nd page 313 Implementation Section 314 Protrusion

Claims

1. stator and, A rotor rotatable relative to the stator, Equipped with, The rotor is A permanent magnet in which different magnetic poles are arranged alternately along the direction of rotation, A support member that supports the permanent magnet, It has, The stator is, Multiple electromagnets arranged along the rotational direction of the rotor, A mounting member to which the aforementioned multiple electromagnets are attached, A magnetic detection unit for detecting the magnetism of the permanent magnet, It has, Each of the aforementioned multiple electromagnets is, Stator core and The coil wound around the stator core, It has, The magnetic detection unit is Hall element or Hall IC, A support substrate for supporting the Hall element or the Hall IC, It has, The Hall element or Hall IC is positioned outside the stator core with respect to the rotation center of the rotor. The support substrate has a mounting portion on which the Hall element or the Hall IC is mounted, and a protruding portion that protrudes from the mounting portion toward the center of rotation, The aforementioned protrusion is positioned between two adjacent electromagnets among the plurality of electromagnets along the direction of rotation. The width of the protrusion is less than or equal to the distance between the stator cores of the two electromagnets. 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 support substrate. The motor according to claim 1.

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

4. The rotor is a first rotor, The system further comprises a second rotor that faces the first rotor across the stator and is connected to the first rotor, The second rotor described above does not have a permanent magnet. The motor according to claim 1 or 2.

5. A motor according to claim 1 or 2, One or more blades that rotate when driven by the motor, Equipped with, Ceiling fan.

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