JP2549357Y2 - Fixed yoke type flat brushless vibration motor - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION This invention relates to a flat brushless vibration motor used as a vibration source as a silent call means for portable radio communication equipment and a vibrator for fatigue recovery equipment.
Data improvement.

[0002]

2. Description of the Related Art Conventionally, as shown in Japanese Patent Application Laid-Open No. 2-21037 and Japanese Patent Application No. 1-138422 proposed by the present applicant, an eccentric weight is deleted and a rotor itself is unmounted. Balanced ones are known.

However, Japanese Unexamined Patent Publication (Kokai) No. 2211037 discloses a rotary yoke type in which the magnet is decentered as a means for obtaining imbalance, and as shown in FIG. It is sucked by the rotating yoke 2,
There is a disadvantage that the air gap is partially reduced and the stator winding 3 is hit, and there is a problem that it must be firmly fixed to the rotor holder 4 by bonding or the like. Therefore, there is a disadvantage that the motor itself becomes large in size. In the figure, 5 is a stay.
A reference numeral 6 denotes a shaft, and 7 denotes a bearing arranged on the stator 5 for receiving the shaft 6.

Japanese Patent Application No. 1-138 previously proposed by the present applicant.
Reference numeral 422 shows a fixed yoke type structure in which the magnet or the magnet holder is cut out from the inner diameter so that the magnet or the magnet holder is shaped like a bevel to drive the sensorless drive so as not to increase the size in the radial direction. That is, as shown in FIG. 4, two bearings, a ball bearing type 8 and an oil-impregnated metal type 7, are used as bearings for supporting the rotor R, and are provided on a magnetic substrate 9 made of an electromagnetic iron plate. A flat magnet 11 in the shape of a jewel is rotatably supported on a rotor support member 10 by a magnet case 12, a rotor holder 13, and a shaft 6 which hold the magnet 11.

[0005] By doing so, the flat magnet 11 in the shape of a magatama is firmly fixed to the rotor holder 13 by caulking means, and no inclination is produced by the upper and lower bearings 8 and 9, so that it is mounted on the magnetic substrate. The possibility that the surface of the magnet 11 abuts against the armature coil thus eliminated is eliminated.

The above-mentioned structure is popular for a brushless vibration motor having a thickness of 4 mm or more.
When a degree is required, a rotary yoke type cannot be constituted, and a fixed yoke type cannot be constituted by a twin bearing type, and a single bearing must be adopted.

[0007]

[Problem to be solved by the invention]
An extremely thin fixed-yoke type brushless vibration motor in which the magnetic flux generated from the magnet is made uniform while the rotor itself is eccentric and even if only one bearing is used, the inclination in the axial direction is prevented. It is intended to provide.

[0008]

According to the present invention, a flat magnet is formed in a disk shape for the above purpose, and a non-magnetic unbalance means is arranged on the flat magnet. The rotor may be supported, a thin return pass plate may be provided on the magnet, and the rotor may be supported by a single bearing to make it extremely thin.

[0009]

In this case, since the magnetic flux from the magnet reaches the magnetic substrate uniformly, the magnet itself does not tilt in the axial direction, so that it can be constituted by a single bearing.

[0010]

FIG. 1 is a sectional view of an essential part of an embodiment in which the structure of the present invention is applied to a fixed-yoke type flat brushless motor having a thickness of about 3 mm. A rotor support member 10 having a shaft 6 press-fitted at the center is fitted on a stator substrate made of the following silicon steel plate, and a plurality of armature coils formed of a thick-film fine pattern are formed above the stator support member. The stator 14 is fixed with an anaerobic adhesive or the like.

Reference numeral 15 denotes a thin annular disk-shaped magnet facing the stator, which is fixed to a brass magnet holder 16 cut out substantially in half.
Is rotatably fitted to the shaft 6 via a small ball bearing 8 which is weakly pressed into the center of the shaft.

In this case, since the magnet is disk-shaped and the magnet holder is non-magnetic, the magnetic flux generated from the surface becomes uniform and the rotor does not tilt.

FIG. 2 shows a disk-shaped magnet 14a having a half-thickness and a return plate 14b made of a magnetic plate instead. In addition, the figure
Although the bearing 8 is used, ordinary oil-impregnated metal may be used.

In this case, the cost of the magnet is advantageous.

[0015]

According to the present invention, the magnet is formed in a disk shape and the magnet holder is formed as a non-magnetic eccentric body as described above, so that even if a single bearing is used as a rotor, the generation of magnetic flux is uniform. Therefore, there is no possibility that the rotor is inclined. Therefore, there is no possibility that the rotor comes into contact with the stator, and an extremely thin brushless vibration motor can be provided.

[Brief description of the drawings]

FIG. 1 shows a fixed-yoke flat brushless vibration mode of the present invention.
FIG. 3 is a cross-sectional view of one embodiment of the present invention.

FIG. 2 is a sectional view of a main part of the second embodiment.

FIG. 3 is a sectional view of a conventional brushless vibration motor.

FIG. 4 is a sectional view of another conventional example.

[Explanation of symbols]

 6 Shaft 7 Oil-impregnated bearing 8 Ball bearing 10 Rotor bearing member 16 Disc-shaped magnet

Claims (4)

(57) [Scope of request for utility model registration] 1. A fixed yaw having a rotor bearing member disposed in the center.
A magnetic substrate, a stator having a plurality of armature coils disposed on the magnetic substrate, and a flat magnet facing the stator through a gap. Fixed yaw equipped with a rotatably supported rotor
A fixed-yoke flat brushless vibration motor in which a flat magnet is formed in a disk shape and a non-magnetic material imbalance means is arranged on the flat magnet. 2. The fixed-yoke flat brushless vibration motor according to claim 1, wherein the rotor is supported by non-magnetic material unbalance means. 3. A fixed-yoke type flat brushless vibration motor according to claim 1, wherein a thin return pass plate is additionally provided to the flat magnet. 4. The fixed-yoke flat brushless vibration motor according to claim 1, wherein the rotor is supported by one bearing.