JP2001186715A - Flat dc motor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve a vibrating force of a flat vibration motor and reduce the thickness and size of the motor. SOLUTION: A plurality of permanent magnets 103, which are fixed to a lower case 106 and have thicknesses, increased from their outer circumference sides toward their inner circumference sides, are made to face an armature 100, which has an armature supporting table 109, which is fixed to a rotary shaft 101, supported rotatably by an upper case 105 and the lower case 106, and on which a plurality of armature coils 102, which are thinner in their inner circumference sides than in their outer circumference sides, are mounted, with conical gaps between.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a flat type vibration motor used for portable equipment, and more particularly to a permanent magnet and an armature coil which are components of a vibration motor which can be reduced in size and thickness. It is related to the configuration of

[0002]

2. Description of the Related Art Conventionally, portable devices such as a PHS and a mobile phone are received by vibration of a vibration motor without depending on sound being received so as not to disturb a quiet environment at the time of reception, such as a concert hall or a hospital. In many cases, a vibration motor that allows a user of a portable device to sense is provided. The vibration motor described above is required to be further improved in order to reduce the size and weight, to reduce the power consumption, to increase the exciting force, and to reduce the cost. To this end, various simplified configurations of the vibration motor have been tried. For example, as a configuration example of a flat DC motor for vibration by an eccentric rotor using a plurality of armature coils (three), see JP-A-6-205565 (Document A) and an armature coil (one). Examples of the configuration of a flat DC motor for vibration by an eccentric rotor using
Japanese Patent Application No. Hei 9-136733 (Document B) is known.

[0003] Document A shows the main configuration of a flat DC motor using three armature coils as shown in Figs. FIG. 3 shows a main sectional view, and FIG. 4 shows an arrangement of three armature coils. Hereinafter, Document A will be described with reference to the drawings.

As shown in FIGS. 3 and 4, a flat DC motor 300 for generating vibration includes a disk-shaped permanent magnet 303 magnetized to four poles in a thickness direction fixed to the bottom of a casing 302. An electric machine in which three fan-shaped coils 306a, 306b, 306c facing each other via a gap are arranged in substantially the same plane, and fixed together with a commutator 308 having a plurality of segments on a rotor shaft 305. And a pair of brushes 309 contacting the commutator 308. When a DC power supply is connected to the pair of brushes 309, three fan-shaped coils 306a, 306b, 306c
Rectified current flows through the armature 304 and the armature 304 rotates in a predetermined direction. To use as a vibration generation motor,
By making the armature 304 largely eccentric, the armature 3
When a large centrifugal force is generated at 04 and it rotates, strong vibration is generated in the whole apparatus.

[0005] Document A discloses that the armature 304 is rotated by the eccentricity of the armature 304 to generate a large centrifugal force and generate a strong vibration in the entire apparatus. No reference is made to the structure of a flat DC motor that can be made thin.

Further, as shown in FIG. 5 in the document B, in order to eliminate the start-up dead center, the magnetic body 2 which determines the stop position of the armature 210 having one armature coil of a fan shape is mounted.
00 is embedded in the armature 210,
00 is eccentric. And the armature 2
Although it is shown that a large centrifugal force is generated by rotation of 00 and strong vibration is generated in the entire apparatus, a structure of a flat DC motor for improving the excitation force is disclosed. Absent.

[0007] Further, in Documents A and B, although there is a difference in the configuration in which three or two armature coils are mounted, a coil having a constant thickness is mounted on the rotor shaft 305. It is composed of an armature 304 and a permanent magnet 303 having a constant thickness. As a result, the armature 304
Is not disclosed in which the center of gravity is disposed on the outer peripheral side of the armature 304. The present invention can arrange the center of gravity of an armature coil on the outer peripheral side of an armature irrespective of the number of armature coils for the purpose of improving the exciting force of the armature of a flat DC motor. The present invention relates to a configuration of an armature coil and a permanent magnet.

[0008]

According to a first aspect of the present invention, there is provided a flat DC motor, wherein a plurality of poles are magnetized in a thickness direction to face a magnetic pole surface of a disk-shaped permanent magnet. In the magnetic field formed by the cup-shaped case, a plurality of fan-shaped coils are disposed in substantially the same plane via the magnetic pole surface of the permanent magnet and a gap, and the rotating shaft is formed of a plurality of segments. In a vibration motor including an armature fixed together with a commutator and a pair of brushes that come into contact with the commutator, an inner peripheral side of the plurality of permanent magnets facing each other via an axial gap with respect to the armature center. Is formed thicker than the outer circumferential side of the permanent magnet, and the inner circumferential side of the armature coil, which is opposed through a gap, is formed to be thinner than the outer circumferential side of the armature coil. The center of gravity of the coil is It is characterized in that located on the outer peripheral side of the.

According to a second aspect of the present invention, there is provided a flat DC motor, wherein the plurality of permanent magnets are disposed above, below, or on one of the armature coils. Is what you do.

According to a third aspect of the present invention, there is provided a flat type DC motor, wherein the configuration of the armature coil is one or two and the armature coil is eccentric with respect to the armature center. It is characterized by having.

[0011]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a normal sectional view of a flat DC motor showing a first embodiment of the present invention. FIG. 2 is a common sectional view of a flat DC motor according to a second embodiment of the present invention. In FIG. 1, a plurality of permanent magnets 103 whose inner peripheral sides are thicker than outer peripheral sides are fixed to a lower case 106. In the armature 100, a plurality of armature coils 102 having a smaller inner thickness than an outer thickness are mounted on an armature support 109 fixed to the rotor shaft 101,
On the back surface of the armature support 109, a flat commutator 107 to which a brush 108 makes contact and conduct electricity is fixed. The rotor shaft 101 is rotatably supported at the center of the upper case 105 and the lower case 106. The armature coil 102 has a conical gap 11 with the permanent magnet 103.
0. As can be seen from FIG.
The center of gravity of 00 is configured to move from the position X of the center of gravity corresponding to the plate-shaped armature coil to the Y side toward the outer peripheral side.

When the armature 100 rotates, a large centrifugal force is generated because the center of gravity of the armature coil 102 is on the outer peripheral side of the armature 100, as described above, whereby the exciting force is improved and the vibration motor is increased. Performance is improved.

In FIG. 2, focusing on the differences from FIG. 1, a plurality of permanent magnets 103 whose inner peripheral side is thicker than the outer peripheral side are provided in the lower case 106 and a plurality of inner peripheral side The permanent magnet 104 whose thickness is larger than the thickness on the outer peripheral side is fixed to the upper case 105. In the armature 100, a plurality of armature coils 112 each having a substantially triangular cross section are mounted on an armature support base 109 fixed to a rotor shaft 101, the inner thickness being smaller than the outer thickness. Child support 1
A flat commutator 107 to which a brush 108 contacts and conducts electricity is fixed to the rear surface of the motor 09. The rotor shaft 1
Reference numeral 01 is rotatably supported at the center of the upper case 105 and the lower case 106. The armature coil 112 has a conical space 110 with the permanent magnet 103,
04 with a conical space 111 interposed therebetween. As can be seen from FIG. 2, the center of gravity of the armature 100 moves from the position X of the center of gravity corresponding to the plate-shaped armature coil to Y to the outer peripheral side.

When the armature 100 rotates, a large centrifugal force is generated because the center of gravity of the armature coil 112 is located on the outer peripheral side of the armature 100 as described above, thereby increasing the excitation force and increasing the vibration motor. Performance is improved.

[0015]

According to the present invention, the vibration force of the vibration motor can be improved with a simple structure, and a vibration motor having a small number of parts and excellent cost / performance can be realized.

Further, according to the present invention, since the permanent magnet and the armature are effectively disposed in the thickness direction, the thickness of the vibration motor can be easily reduced.

[Brief description of the drawings]

FIG. 1 is a diagram showing a first embodiment of a flat DC motor according to the present invention.

FIG. 2 is a diagram showing a flat DC motor according to a second embodiment of the present invention.

FIG. 3 is an explanatory view of a main section of Document A of a conventional example.

FIG. 4 is an explanatory diagram showing the arrangement of three armature coils of Document A of a conventional example.

FIG. 5 is an explanatory diagram of a plan view of Document B of a conventional example.

FIG. 6 is an explanatory diagram of a cross-sectional view of a conventional example.

[Explanation of symbols]

 REFERENCE SIGNS LIST 100 armature 101 rotor shaft 102, 112 armature coil 103, 104 permanent magnet 105 upper case 106 lower case 107 commutator 108 brush 109 armature support 110, 111 gap

Claims (3)

[Claims] In a magnetic field formed by a disk-shaped permanent magnet having a plurality of poles magnetized in a thickness direction and a cup-shaped case opposed to the disk-shaped permanent magnet, a plurality of magnetic poles are provided through a gap between the magnetic pole surface of the permanent magnet and a gap. A vibrating motor comprising: an armature having a plurality of fan-shaped coils disposed substantially in the same plane and fixed to a rotor shaft together with a commutator comprising a plurality of segments; and a pair of brushes contacting the commutator. The thickness of the plurality of permanent magnets facing each other via an air gap in the axial direction with respect to the center of the armature is formed to be thicker than the thickness of the outer periphery of the permanent magnets, and the motor facing the armature via a gap is provided. A flat DC motor, wherein an inner peripheral side thickness of the armature coil is formed smaller than an outer peripheral side thickness of the armature coil, and a center of gravity of the armature coil is located on an outer peripheral side of the armature. 2. The flat DC motor according to claim 1, wherein the plurality of permanent magnets are arranged above, below, or one of the armature coils. 3. The structure of the armature coil is one or two.
The flat DC motor according to claim 1 or 2, wherein the motor is eccentric with respect to the armature center.