JP4504495B2 - Brushless motor - Google Patents

Description

[0001]
[Industrial application fields]
The present invention consists sintered metal body obtained by compacting, of a medium-relief type oil bearing as a motor shaft was fitted into the housing, relates beginning with the improvement of the brushless motor the spindle motor, enables the exchange of the bearing Thus, it is an object to remarkably improve the durability of the motor.
[0002]
[Prior art]
The structure of a conventionally known spindle type motor has a large diameter portion formed at the center of the inner peripheral surface as a bearing unit, for example, in order to reduce the frictional resistance between the rotating shaft and the bearing and suppress the temperature rise during continuous rotation. A so-called “medium escape type” bearing, such as a bearing (Japanese Patent Laid-Open No. 11-294457) or a bearing formed with a relief that does not come into contact with the shaft member (Japanese Patent Publication No. 8-6124). The ones used are the mainstream.
[0003]
[Problems to be solved by the invention]
However, most of the spindle motors using these intermediate relief type bearings are designed to be used for high-precision and high-quality driving such as VTR, DVD-ROM or CD-ROM disk drive. When the bearings are worn out due to their intended use, it is necessary to replace the spindle motor each time, and an increase in cost is unavoidable in the maintenance and management of the high-quality equipment. In addition, discarding the motor itself not only raises the cost described above, but also places a heavy load on the environment. In this respect as well, it is desired to improve the maximum recycling rate.
[0004]
[Means for Solving the Problems]
Accordingly, the present invention solves the above-described problems in the prior art, and improves durability and reliability, and also reduces maintenance costs, particularly as a motor drive source with advanced functions such as AV and various information devices. At the same time, it has improved the recycling rate of substances and resources that have an impact on the environment, and contributed to ecology. Specifically, an oil-impregnated bearing made of a medium escape type sintered metal body was installed as a motor bearing. In the motor, a non-circular-shaped flange portion extending in a direction perpendicular to the axis and extending in the radial direction is formed at the non-output side end of the motor bearing, and the flange portion is formed on the non-output side on the housing holder side. Fits into a recess formed in the inner diameter near the opening edge, for example, a recess that is a non-circular shape by providing a protrusion on the inner edge of the housing holder opening edge. It was constructed removably motor bearings by not binding for a brushless motor according to claim.
[0008]
The present invention also relates to a brushless motor in which a housing holder is fixed to a base and a laminated core and a coil are provided on an outer peripheral surface. Further, according to the present invention, the housing holder is fixed to the base, the outer peripheral surface is provided with a laminated core and a coil, and the motor shaft held by the bearing press-fitted into the housing holder is provided outside the laminated core. Further, the present invention relates to a brushless motor in which a rotor yoke having a magnet on the inner peripheral side thereof is integrally attached.
[0009]
The present invention further relates to a brushless motor which is a spindle motor in which a turntable for attaching a rotating medium to one end of a motor shaft is integrally attached. Furthermore, the present invention relates to a brushless motor that is used as a fan motor by attaching a fan to one end of a motor shaft.
[0010]
In the above configuration, when the brushless motor bearing is worn or the impregnated oil is consumed, remove the cover that is detachably attached to the non-output side of the motor, and pull the motor bearing to the non-output side of the motor. If it is replaced with a new bearing and the bearing flange is fitted and connected to the housing holder side, the bearing is opened on the housing holder side by rotating the bearing around the shaft center by a certain angle in the circumferential direction. Release and remove the fitting from the edge, pull out the motor bearing to the non-output side of the motor, and replace with a new bearing.
[0011]
DETAILED DESCRIPTION OF THE INVENTION
In the following, the specific contents of the present invention are based on the first embodiment of the spindle motor of FIG. 1 in which a middle escape type bearing is used for the motor shaft and the bearing flange portion is fitted and coupled to the housing holder side. In the following description, 1 is a housing holder, 7 is a bearing, and 10 is a motor shaft. The housing holder 1 is composed of a cylindrical portion 2 and a flange 3 extending in an orthogonal outward radial direction from one longitudinal end of the cylindrical portion 2, and on the inner peripheral surface of the rising portion (base portion) of the flange 3, A concave portion 4 is formed at the opening end of the cylindrical hole of the cylindrical portion 2 while leaving the protruding portions 5 formed at symmetrical positions such as two or three on the left and right.
[0012]
Further, a laminated core 6 around which a coil 6 a is wound is applied to the outer peripheral surface of the cylindrical portion 2 in the housing holder 1. The bearing 7 is formed by compacting metal powder such as copper into a size that can be inserted into the housing holder 1 described above, then sintering the powder and impregnating it with oil, and in the middle of the shaft hole. The middle escape portion 9 is formed, and the motor shaft 10 is supported at both ends in the length direction. Further, a flange 8 directed to the outer radial direction perpendicular to the length direction is formed at one end thereof, Moreover, the flange 8 has a non-circular structure by forming a flat portion 8a so that symmetrical portions are parallel to each other (see FIG. 2).
[0013]
Further, the motor shaft 10 is made of a metal rod having an outer diameter that can be supported in the bearing 7, and the outer portion of the laminated core 6 and the coil 6 a is disposed on a portion near the tip located on the output side of the motor via a holding material 11. And a rotor yoke 12 provided with a magnet 13 is integrally attached at a position corresponding to the laminated core 6 on the inner circumference side, and further, a CD-ROM disk or the like is provided at the tip thereof. A turntable 14 for a disk drive on which the rotating medium M is placed is also integrally attached. In the figure, H represents a Hall element.
[0014]
FIG. 3 shows a second embodiment of the present invention. This is a brushless motor placed horizontally (with the motor shaft 10 oriented in the horizontal direction), for example, as a cooling fan motor. The basic configuration of the brushless motor is the same as that of the first embodiment described above. Similarly, a fan F is attached to the tip of the motor shaft 10 located on the output side of the motor, and an outer periphery is provided on the opposite motor shaft end located on the opposite side of the motor (the back side of the motor). A groove 15 having a certain depth opened in the direction is formed over the entire circumference, a washer 16 is interposed, and a retaining ring or a clip ring (C ring) 17 is fitted into the bearing 7 so as to be stably held. In addition, the laminated core 6 around which the coil 6a is wound and the portion of the rotor yoke 12 positioned on the outer peripheral side thereof are covered with an outer casing C. It has become.
[0015]
In the configuration of the first embodiment described above, the flange 3 of the housing holder 1 is attached to the base (PCB) B, and the bearing 7 is inserted into the cylindrical portion 2 of the housing holder 1 from the non-output side of the motor. 7 is inserted into the concave portion 4 of the cylindrical portion 2, and the spring S is interposed between the side wall of the concave portion 4 and the bearing 7 is rotated by a certain angle in the circumferential direction to make the non-circular shape of the bearing 7. The flange 8 thus engaged is engaged with the back side of the protruding portion 5 and held.
[0016]
Further, the motor shaft 10 to which the rotor yoke 12 and the turntable 14 are attached is inserted into the bearing 7 from the output side of the motor. In the case of the fan motor of the second embodiment, the thrust washer 16 is attached to the motor shaft 10 from the non-output side of the motor in the state shown in FIG. Then, a retaining ring or a clip ring (C ring) 17 is fitted into the groove 15 to constitute a fan motor.
[0017]
In the first and second embodiments described above, the motor bearing is detachable on the counter-output side of the motor, and on the counter-output side of the motor, the motor bearing end is in a direction perpendicular to the axis, A base or base is formed by forming a flange portion extending in the radial direction of the outer periphery and making the flange portion a non-circular shape, and fitting and coupling it into a non-circular concave portion formed at the opening edge on the housing holder side. In addition to this, for example, although not shown, a cover for receiving the motor bearing and the motor shaft end is attached to the non-output side of the motor, and the cover is configured to be removable. Also good.
[0018]
In the above configuration, if the bearing is worn, remove the cover that is detachably attached to the non-output side of the motor, then pull the bearing to the non-output side of the motor, or fit the bearing flange to the housing holder side. If they are coupled, the bearing is released from the opening edge on the housing holder side by rotating the bearing around the shaft center by a certain angle in the circumferential direction. Pull out and replace with a new bearing.
[0019]
【The invention's effect】
As described above, the present invention is a motor in which a middle escape type bearing is inserted as a motor bearing, and the cover for receiving the bearing and the motor shaft end is detachably attached on the opposite output side of the motor, or the flange portion is a housing holder. Since the above bearing is configured to be detachable by fitting and coupling to the side, etc., when the bearing wears over time due to the use of a brushless motor, or when the lubricating oil impregnated in the bearing is consumed, the non-output side of the motor The bearings can be easily pulled out and replaced. Especially, as a motor drive source with advanced functions such as AV and various information devices, durability and reliability can be improved and maintenance cost can be reduced.
[0020]
Further, by making it possible to easily replace only a bearing with a worn motor, not only the problem of maintenance cost but also the environment load is reduced, the recycling rate is increased, and the ecology is greatly contributed. Furthermore, as a structure for fixing and holding the flange portion of the bearing to the housing holder fixed to the base, the flange portion is made into a non-circular shape and fitted into a recess formed in the opening edge portion on the housing holder side. In the case of the structure to be coupled, the removal of the bearing is further simplified, and the bearing replacement operation can be speeded up and the maintainability can be further improved.
[Brief description of the drawings]
FIG. 1 is an enlarged cross-sectional view showing an attachment state of a brushless motor according to a first embodiment of the present invention to a base.
FIG. 2 is an enlarged perspective view of a bearing and an enlarged plan view seen from the flange side.
FIG. 3 is an enlarged cross-sectional view showing the structure of a fan motor according to a second embodiment of the present invention.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Housing holder 2 Cylindrical part 3 Flange 4 Recessed part 5 Protruding part 6 Laminated core 6a Coil 7 Bearing 8 Flange 8a Flat part 9 Middle escape part 10 Motor shaft 11 Holding material 12 Rotor yoke 13 Magnet 14 Turntable 15 Groove 16 Washer 17 Retaining ring or Clip ring M Rotating media F Fan C Casing S Spring H Hall element

Claims (6)

In a motor in which an oil-impregnated bearing made of a medium escape type sintered metal body is inserted as a motor bearing, a non-circular shape extending in the radial direction of the outer periphery of the motor bearing in the direction perpendicular to the axis and extending radially outward A brushless motor comprising a flange portion and a motor bearing that is detachable by fitting and coupling the flange portion into a recess formed in an inner diameter portion near the opening edge on the opposite side of the housing holder. . 2. The recess according to claim 1, wherein the concave portion formed in the inner diameter portion near the opening edge on the opposite side of the housing holder is a non-circular shape provided with a protrusion directed toward the inner circumferential direction on the opening edge side of the housing holder. Brushless motor. The brushless motor according to claim 1 or 2 , wherein the housing holder is fixed to the base and a laminated core and a coil are provided on the outer peripheral surface. The housing holder is fixed to the base, and the outer peripheral surface is provided with a laminated core and a coil, and the motor shaft held by the bearing press-fitted into the housing holder covers the outside of the laminated core, and The brushless motor according to any one of claims 1 to 3, wherein a rotor yoke having a magnet on an inner peripheral side is integrally attached. The brushless motor according to any one of claims 1 to 4, which is a spindle motor in which a turntable for attaching a rotating medium to one end of a motor shaft is integrally attached. The brushless motor according to any one of claims 1 to 4 , wherein a fan is attached to one end of the motor shaft and used as a fan motor.

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