JP2022152336A - motor - Google Patents

Abstract

To provide an oscillation motor which can be assembled better.SOLUTION: A motor 1 comprises: a rotor having a rotor body 82 rotatable around a central axis J; a pair of coils 32 that face the rotor body in an axial direction and are arranged at different positions in a circumferential direction around the central axis; a substrate having an attachment surface 21 to which the pair of coils are attached; and a magnetic sensor 5 attached on the attachment surface. On the attachment surface, a pair of connection parts 73 and 74 to which leading wires 421 and 422 drawn from the pair of coils are respectively connected are provided. The magnetic sensor and the pair of connection parts are arranged at different positions between the pair of coils in the circumferential direction around the central axis. Each coil is in a circular shape when viewed in the axial direction.SELECTED DRAWING: Figure 1

Description

The present invention relates to motors.

A vibration motor having a thin disc shape is known as a motor used for a silence notification function or the like in various devices. For example, Japanese Laid-Open Patent Publication No. 2002-100000 describes a motor that is radially miniaturized.

JP 2016-100945 A

Further miniaturization is demanded for the vibration motor as described above. If the size of the base portion is reduced in order to reduce the size of the motor, the arrangement of the components of the motor and the wiring space for the coils become narrower, making assembly difficult.

SUMMARY OF THE INVENTION In view of the above circumstances, it is an object of the present invention to provide a motor that can be easily assembled.

One aspect of the motor of the present invention includes a rotor having a rotor body rotatable about a central axis, and a pair of rotors that face the rotor body in the axial direction and are arranged at different positions in the circumferential direction around the central axis. a substrate having a mounting surface on which the pair of coils are mounted; and a magnetic sensor mounted on the mounting surface. The mounting surface is provided with a pair of connection portions to which lead wires drawn out from the pair of coils are connected. The magnetic sensor and the pair of connection portions are arranged at different positions between the pair of coils in the circumferential direction around the central axis. The coil is circular when viewed in the axial direction.

According to one aspect of the present invention, it is possible to improve the assemblability of the motor.

FIG. 1 is a schematic configuration diagram schematically showing the motor of the first embodiment. FIG. 2 is a sectional view taken along line II-II of FIG. FIG. 3 is a schematic configuration diagram schematically showing the motor of the second embodiment.

Hereinafter, motors according to embodiments of the present invention will be described with reference to the drawings. The scope of the present invention is not limited to the following embodiments, and can be arbitrarily changed within the scope of the technical idea of the present invention.

In the following description, unless otherwise specified, the direction parallel to the central axis J (the Z-axis direction) is simply referred to as the "axial direction", the -Z side is simply referred to as the one side in the axial direction, and the +Z side is simply referred to as the axial direction. called the other side. The circumferential direction around the central axis J is simply called "circumferential direction", and the radial direction with respect to the central axis J is simply called "radial direction".

(First embodiment)
FIG. 1 is a schematic configuration diagram schematically showing the driving device of the first embodiment. FIG. 2 is a sectional view taken along line II-II of FIG. The motor 1 of this embodiment is a vibration motor. Motor 1 is a brushless motor. Motor 1 is a single-phase motor. A motor 1 is mounted in an electronic device such as a smartphone, for example. The motor 1 generates vibration when driven, and exhibits, for example, a silent notification function of electronic equipment. In FIG. 1, in order to show the positions of the coils 31 and 32, the rotor body 82 and the magnets 83 are partially omitted.

The motor 1 includes a substrate 2 , a rotor 8 , a pair of coils 31 and 32 and a magnetic sensor 5 . Motor 1 further comprises a cover 6 .

The board 2 has a circuit board (not shown), a mounting surface 21 and a connection portion 7 . As shown in FIG. 1, the substrate 2 of this embodiment has a substantially circular shape when viewed from the axial direction. For example, the radial dimension of the substrate 2 is 8 mm or less. The mounting surface 21 is located on one side of the substrate 2 in the axial direction. A connecting portion 7 is provided on the mounting surface 21 . The connecting portion 7 is a contact that is electrically connected to the circuit board through the lead wire 4 . The connecting portion 7 is, for example, a land of a printed circuit board or a flexible printed wiring board.

The cover 6 is a substantially cylindrical container. The cover 6 covers the board 2 and various components of the motor 1 provided on the board 2 .

A rotor 8 is provided at the center of the substrate 2 . The rotor 8 includes a shaft 86 , a rotor body 82 , magnets 83 , bearing portions 81 , support portions 84 and spacers 85 . As shown in FIG. 2, the shaft 86 is provided so as to protrude from the mounting surface toward the other axial side -Z. Shaft 86 has a cylindrical shape. Both axial end portions 861 and 862 of the shaft 86 are fixed to the substrate 2 and the cover 6 . A first end 861 on one axial side -Z of the shaft 86 is fixed to the substrate 2 . A second end 862 on the other +Z side in the axial direction of the shaft 86 is fixed to the cover 6 . A support portion 84 is provided on the mounting surface 21 at the fixed location between the shaft 86 and the substrate 2 . The support portion 84 is an annular member having an axially penetrating hole. A first end 861 of the shaft 86 is disposed within the hole of the support portion 84 and fixed to the mounting surface 21 . The support portion 84 supports the shaft 86 with respect to the substrate 2 .

The bearing portion 81 is a substantially cylindrical member centered on the central axis J. As shown in FIG. A shaft 86 is inserted into the through hole 811 of the bearing portion 81 . The bearing portion 81 is arranged on the other side +Z in the axial direction of the support portion 84 .

The spacer 85 is provided between the bearing portion 81 and the support portion 84 in the axial direction. The spacer 85 is a disk-shaped member. The spacer 85 holds the axially spaced position between the bearing portion 81 and the coils 31 and 32 . Each axial surface of the spacer 85 contacts the bearing portion 81 and the support portion 84 . The spacer 85 is a member having a small coefficient of friction on the contact surface between the bearing portion 81 and the spacer 85 when the rotor body 82 rotates. The spacer 85 is in contact with the rotor body 82 without hindering its rotation. A lubricant may be provided between the spacer 85 and the bearing portion 81 .

The rotor main body 82 is a member that can rotate around the central axis J. As shown in FIG. The rotor body 82 is attached to the bearing portion 81 . The rotor body 82 is rotatably attached to the shaft 86 via the bearing portion 81 . The rotor main body 82 has an annular magnet mounting portion 822 along the radial direction and a cylindrical fixing portion 821 positioned at the center of the circle. As shown in FIG. 2 , the fixing portion 821 protrudes from the opening edge at the center of the magnet mounting portion 822 toward the other side +Z in the axial direction. The bearing portion 81 is inserted into the opening of the fixed portion 821 . A fixed portion 821 is fixed to the bearing portion 81 . The magnet mounting portion 822 is positioned on the other side +Z in the axial direction of the coils 31 and 32 .

Magnet 83 is an annular member. A magnet 83 is fixed to the surface of the magnet attachment portion 822 on the one axial side -Z. The magnet 83 is mounted so that the shaft 86 and the bearing portion 81 are inserted and the center is positioned on the central axis J. As shown in FIG. The magnet 83 faces the coils 31 and 32 in the axial direction. The magnet 83 faces the coils 31 and 32 at a position away from the other side +Z in the axial direction. A spacer 85 maintains the axial distance between the magnet 83 and the coils 31 and 32 .

The rotor 8 includes a bearing portion 81 , a rotor body 82 , and magnets 83 coaxially arranged on the center axis J. As shown in FIG. A magnet 83 is fixed to the rotor body 82 . The magnet 83 is fixed to the bearing portion 81 via the rotor body 82 . The bearing portion 81 is rotatably attached to the shaft 86 . Therefore, rotor body 82 and magnets 83 are rotatably mounted on shaft 86 .

A pair of coils 31 and 32 are attached to the attachment surface 21 of the substrate 2 . The pair of coils 31 and 32 are arranged radially outward of the shaft 86 . Each of the coils 31 and 32 is configured by winding a coil wire in a substantially cylindrical shape. Each coil 31, 32 has a circular shape when viewed in the axial direction. Each coil 31, 32 has a cylindrical shape. Center axes J31 and J32 of the coils 31 and 32 are arranged parallel to the center axis J. As shown in FIG. Lead wires 4 at both ends of each coil wire are connected to connecting portions 7 . Each of the coils 31 and 32 is supplied with current from the circuit board through the connecting portion 7 . A pair of coils 31 and 32 are arranged to face the magnet 83 in the axial direction.

The magnetic sensor 5 is attached to the attachment surface 21 . A magnetic sensor 5 detects the rotational position of the magnet 83 . The magnetic sensor 5 is, for example, a Hall element. The magnetic sensor 5 may be attached directly to the attachment surface 21 . Alternatively, the magnetic sensor 5 may be provided inside the drive circuit IC of the motor 1 .

Since the motor 1 of this embodiment is a vibration motor, the weight 9 is provided. As shown in FIG. 2, weight 9 is attached to rotor 8 . The weight 9 is provided in a partial region of the rotor body 82 in the circumferential direction. The weight 9 is arranged across the axial direction other side +Z of the magnet mounting portion 822 of the rotor body 82 , the radially outer side, and the radially outer side of the magnet 83 . The weight 9 is not an essential component of the motor according to the invention. For example, when applying the motor of the present invention to a motor other than a vibration motor, the weight 9 is not provided.

Next, the arrangement of each member in the motor 1 will be described. As shown in FIG. 1, in the motor 1, the shaft 86 is arranged at the center of the substrate 2, and the pair of coils 31 and 32, the connecting portion 7, and the magnetic sensor 5 are arranged radially outside the shaft 86. As shown in FIG. The pair of coils 31 and 32 are arranged on opposite sides of the center axis J in the radial direction. In this embodiment, a pair of coils 31 and 32 are arranged side by side in the radial direction with the center axis J interposed therebetween. The pair of coils 31 and 32 is not limited to being arranged on the diametrical line with the center axis J interposed therebetween. The pair of coils may be arranged radially outside of the shaft and spaced apart in the circumferential direction. The connecting portion 7 and the magnetic sensor 5 are arranged at different positions between the pair of coils 31 and 32 in the circumferential direction around the central axis.

The mounting surface 21 is provided with a first region 21a and a second region 21b. The first region 21a and the second region 21b are regions in which the mounting surface 21 is arranged in a circumferential direction around the central axis. The first region 21 a is located on one side in the circumferential direction of one of the pair of coils 31 and 32 and on the other side in the circumferential direction of the other coil 32 . The second region 21b is located on the other side in the circumferential direction of the one coil 31 and on the one side in the circumferential direction of the other coil 32 . On the mounting surface 21, two circumferential regions between the pair of coils 31 and 32 are a first region 21a and a second region 21b. The connecting portion 7 is provided in the first region 21a. A plurality of connection portions 7 are provided corresponding to each lead wire 4 of each coil 31 , 32 . Two connection portions 71 and 72 respectively connected to the two lead wires 411 and 412 of one coil 31 and two connection portions 73 and 74 respectively connected to the two lead wires 421 and 422 of the other coil 32 are the first. 1 region 21a. Each lead wire 4 is wired in a substantially straight line from each coil 31 , 32 . The magnetic sensor 5 is provided in the second area 21b.

In the motor 1 , torque is generated between the coils 31 , 32 and the magnet 83 when current is supplied from the connecting portion 7 to the coils 31 , 32 . The generated torque causes the bearing 81 , the rotor body 82 , and the magnets 83 to rotate about the central axis J with respect to the shaft 86 . Since the weight 9 is attached to the rotor 8, the weight 9 also rotates. The weight 9 eccentrically rotates the rotor 8 and generates vibration.

According to the motor 1 of this embodiment, since the coils 31 and 32 are circular when viewed from the axial direction, the ease of assembly can be improved. Specifically, it is sufficient that the coils 31 and 32 that face the rotor 8 in the axial direction are arranged parallel to the shaft 86 . Therefore, it is not necessary to align the coils 31 and 32, and the coils 31 and 32 can be easily installed.

A fan-shaped coil is used for the coil of a conventional motor in order to improve the magnetization efficiency of the magnet. The fan-shaped coil has a fan-shaped or substantially trapezoidal shape when viewed in the axial direction in accordance with the annular shape of the magnet. Specifically, it has an arcuate surface facing the shaft and is fan-shaped with the central axis J as the center. In the fan-shaped coil, both ends of the coil wire are pulled out from both ends of the circular arc shape in the circumferential direction. The lead wires of the fan-shaped coil are oriented in a certain direction. Therefore, in order to connect the fan-shaped coil to the connecting portion provided circumferentially apart, it was necessary to unwind the coil wire about halfway around and wire up to the connecting portion. In contrast, the coils 31 and 32 of this embodiment are circular when viewed in the axial direction. Therefore, it is not necessary to align the coils 31 and 32 in the radial direction by matching the circular arc surface to the radial direction of the shaft as in the case of the fan-shaped coil. In other words, the circular coils 31 and 32 need only have their central axes parallel to the central axis line J. As a result, each coil 31, 32 can be easily attached. Furthermore, as shown in FIG. 1 , in the case of circular coils 31 and 32 , lead wires 4 are drawn out to the sides of the coils 31 and 32 . Therefore, the circular coils 31 and 32 simplify the routing process of the terminals of the pair of lead wires 411, 412, 421 and 422, and the lead wires 4 can be wired easily. Since the coils 31 and 32 are circular, the lead wire processing can be simplified when the coils 31 and 32 are manufactured. Since the coils 31 and 32 are simple circles, the accuracy of the inner diameter guide jig used in the bonding process for fixing the coils 31 and 32 to the mounting surface 21 can be improved.

In the motor 1 of the present embodiment, the connecting portion 7 is provided in the first region 21a between the pair of coils 31 and 32, and the magnetic sensor 5 is provided in the second region 21b. Therefore, even when a plurality of connection portions 7 are provided in limited places on the mounting surface 21 of the substrate 2, the connection portions 7 are provided between the pair of coils 31 and 32 in accordance with the miniaturization. Easy. Since the magnetic sensor 5 is provided in the second region 21 b , the connection portion 7 and the magnetic sensor 5 do not interfere with each other, and the lead wire 4 can be easily connected to the connection portion 7 .

Since the motor 1 of this embodiment is easy to wire, it is useful in the case of a small single-phase motor. The motor 1 of this embodiment is particularly useful as a small motor having a radial dimension of the substrate 2 of 8 mm or less, for example. In the case of a small motor in which the substrate 2 has a diameter of 8 mm or less, even if the coils 31 and 32 are circular, the difference in performance from the conventional fan-shaped coil is small. Therefore, it is possible to provide the motor 1 in which the miniaturization and the performance of the motor are not at odds with each other and the performance is well-balanced. For the purpose of providing a motor with easy wiring and improved assembly, the motor may have a substrate 2 with a diameter larger than 8 mm.

(Second embodiment)
In the above embodiment, the pair of coils 31 and 32 are arranged on the diameter line across the central axis J, the connection portion 7 is provided in the first region 21a, and the magnetic sensor 5 is provided in the second region 21b. Although shown, the motor is not limited to this example. For example, it may be the motor 1A of the second embodiment shown in FIG. In the following description, the same reference numerals are given to the same components as those already described, and duplicate descriptions will be omitted.

FIG. 3 is a schematic configuration diagram schematically showing the motor 1A of the second embodiment. The motor 1A of this embodiment differs from that of the first embodiment in the positions of the pair of coils 31 and 32 and the connecting portion 7. As shown in FIG. The pair of coils 31 and 32 are arranged such that the central axes J31 and J32 of the respective coils 31 and 32 are arranged at positions where the angle between the radial lines r1 and r2 from the central axis J is 120 degrees. Therefore, the second region 21b is wider than the first region 21a. A pair of connection portions 73 and 74 for the other coil 32 are provided in the first region 21a. A pair of connection portions 71 and 72 for one coil 31 and the magnetic sensor 5 are provided in the second region 21b. The lead wires 421 and 422 of the other coil 32 are led out substantially linearly to the first region 21a and connected to the connecting portions 73 and 74, respectively. The lead wires 411 and 412 of one coil 31 are led out substantially linearly to the second region 21b and connected to the connecting portions 71 and 72, respectively.

According to the motor 1A of the present embodiment, as in the first embodiment, the ease of assembly can be improved. According to the motor 1A of this embodiment, since the circular coils 31 and 32 are used, wiring of the lead wires 4 is easy. Therefore, as in the motor 1A of the present embodiment, even if the connecting portion 71 of one coil 31 is provided in the second region 21b and the connecting portions 73 and 74 of the other coil 32 are provided in the first region 21a, the Wiring is possible. Since the wiring of the coils 31 and 32 of the motor 1A is easy, there is a high degree of freedom in designing the layout of the parts on the mounting surface 21 . In the motor 1A of this embodiment, the pair of coils 31 and 32 are arranged 120 degrees apart in the circumferential direction. can be set to

The embodiments and modifications of the present invention have been described above. can be changed. Moreover, the present invention is not limited by the embodiments.

DESCRIPTION OF SYMBOLS 1... Motor, 2... Substrate, 5... Magnetic sensor, 4, 411, 412, 421, 422... Lead line, 7, 71, 72, 73, 74,... Connection part, 8... Rotor, 21... Mounting surface 21a ...first area 21b...second area 31, 32...coils 82...rotor main body J...center axis

Claims (5)

a rotor having a rotor body rotatable about a central axis;
a pair of coils axially opposed to the rotor main body and arranged at different positions in the circumferential direction around the central axis;
a substrate having a mounting surface on which the pair of coils are mounted;
a magnetic sensor attached to the mounting surface;
with
The mounting surface is provided with a pair of connection portions to which lead wires drawn out from the pair of coils are connected, respectively;
The magnetic sensor and the pair of connection portions are arranged at different positions between the pair of coils in the circumferential direction around the central axis,
A motor in which the coil has a circular shape when viewed in the axial direction. The mounting surface has
a first region located on one side in the circumferential direction of one of the pair of coils and on the other side in the circumferential direction of the other coil;
a second region positioned on the other side in the circumferential direction of the one coil and on the one side in the circumferential direction of the other coil;
is provided,
The pair of connection portions are provided in the first region,
The motor according to claim 1, wherein the magnetic sensor is provided in the second area. 3. The motor according to claim 1, wherein the pair of coils are arranged on opposite sides across the central axis in a radial direction. 4. A motor according to any one of claims 1 to 3, which is a single-phase motor. The motor according to any one of claims 1 to 4, wherein the substrate has a radial dimension of 8 mm or less.

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