JP2551104Y2 - Bearing device - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a bearing device for a rotating body, and more particularly to a bearing device for holding a bearing by press-fitting a housing.

[0002]

2. Description of the Related Art FIG. 5 is an exploded perspective view showing the structure of an example of a conventional bearing device for a rotating body, and FIG. 6 is an FD using the example of FIG.
It is sectional drawing which shows an example of the spindle motor for D.

As shown in FIG. 5, a conventional bearing device for a rotating body which presses a bearing into a housing to hold the bearing is provided with a rotating shaft 21 and a bearing 22 for supporting the rotating shaft 21.
And a main body 23 having a housing for holding the bearing 22
And a rotor 24 for giving a rotating motion to the rotating shaft 21, and a flat screw 25 for fixing the rotor 24 to the rotating shaft 21.

[0004] The bearing device configured as described above outputs the rotational motion of the rotor 24 to the rotating shaft 21. The bearing 22 is
The rotating shaft 21 is supported so as to rotate smoothly. Main unit 2
3 has a housing for holding the bearing 22, and is a basic part of the present apparatus. The rotor 24 is a motor that converts a force generated by the stator core and the magnet into a rotary motion, or a pulley that converts a force transmitted from an external power into a rotary motion. The flat screw 25 is connected to the rotating shaft 21 and the rotor 2.
4 and fixed.

[0005]

In the conventional bearing device as described above, when the external force A in the axial direction acts on the rotor 24, the rotor 24 comes into direct contact with the bearing 22, as shown in FIG. There is a possibility that the bearing 22 pressed and held in the housing of the main body 23 may move or come off,
For this reason, it is necessary to increase the press-fitting strength of the bearing 22.
If the press-fit allowance is increased to increase the press-fit strength, the bearing 2
2 has a problem that dimensional control of the bearing 22 is not easy because deformation and reduction of the inner diameter occur.

[0006]

SUMMARY OF THE INVENTION A bearing device according to the present invention includes a rotating shaft, a bearing for supporting the rotating shaft, a main body having a housing for holding the bearing, and a rotor for imparting a rotating motion to the rotating shaft. In the bearing device comprising: the diameter of the squeezed portion of the screw fastening portion of the rotor is larger than the diameter of the bearing, or between the squeezed portion of the screw fastening portion of the rotor and the housing of the main body portion. A washer having a diameter larger than the diameter of the bearing is provided.

[0007]

Next, an embodiment of the present invention will be described with reference to the drawings.

FIG. 1 is an exploded perspective view showing a configuration of a first example in which the present invention is applied to a spindle motor of a floppy disk drive (FDD), and FIG. 3 is a sectional view of the example of FIG.

In this embodiment, as shown in FIG. 1, a bearing 2 is press-fitted and held in a housing of a main body 3 having a built-in stator core, and a rotating shaft 1 having a hub, a force generated by the stator core and a magnet. And a rotor 4 for converting the rotational motion into a rotational motion are incorporated by a flat screw 5. Bearing 2
As shown in FIG. 3, the upper surface is press-fitted so as to coincide with the upper surface of the main body portion 3 or slightly lower than the upper surface of the main body portion 3. The portion (fastening portion) of the rotor 4 into which the flat screw 5 is inserted is squeezed so that the upper surface of the flat screw 5 does not protrude above the surface of the rotor 4. 3 is larger than the inner diameter of the press-fit portion of the bearing 2, that is, the outer diameter of the bearing 2.

In the FDD spindle motor configured as described above, the rotor 4 and the main body 3 do not come into contact with each other during normal rotation as shown in FIG.
When an external force A acts on the rotor 4 as shown in FIG. 2, the throttle portion of the rotor 4 comes into contact with the housing of the main body 3 and the external force A is transmitted to the main body 3. However, since the diameter of the lower surface of the throttle portion of the rotor 4 is larger than the outer diameter of the bearing 2, the external force A
Is not transmitted to the bearing 2, so that the bearing 2 does not move or come off.

FIG. 2 is an exploded perspective view showing the configuration of a second example in which the present invention is applied to a spindle motor of a floppy disk drive (FDD), and FIG. 4 is a sectional view of the example of FIG.

In this embodiment, as shown in FIG. 2, a bearing 12 is press-fitted and held in a housing of a main body 13 having a built-in stator core, and a rotary shaft 11 having a hub therein, a washer 16, a stator core and a magnet. And a rotor 14 for converting the force generated by the rotation into a rotary motion. As in the embodiment of FIG. 1, the bearing 12 is press-fitted so that its upper surface coincides with the upper surface of the main body 13 or slightly lower than the upper surface of the main body 13. The portion (fastening portion) of the rotor 14 into which the flat screw 15 is inserted is narrowed so that the upper surface of the flat screw 15 does not protrude above the surface of the rotor 14. 13 is smaller than the inner diameter of the press-fit portion of the bearing 12, that is, the outer diameter of the bearing 12,
The outer shape of the washer 16 provided between the body 4 and the body 13 is as follows.
It is larger than the outer diameter of the bearing 12.

In the FDD spindle motor thus configured, the rotor 14 and the main body 13 do not come into contact with each other during normal rotation as shown in FIG.
As shown in (b), when an external force A acts on the rotor 14, the throttle portion of the rotor 14 contacts the housing of the main body 13 via the washer 16 and transmits the external force A to the main body 3. However, since the outer diameter of the washer 16 is larger than the outer diameter of the bearing 12, the external force A is not transmitted to the bearing 12, and therefore, the bearing 12 does not move or slip off.

[0014]

As described above, in the bearing device of the present invention, when an external force acts on the rotor in the axial direction, the external force is transmitted from the throttle portion of the rotor to the main body and is not transmitted to the bearing. There is an effect that it can be prevented from moving or coming off.

[Brief description of the drawings]

FIG. 1 shows a floppy disk drive (FD)
It is an exploded perspective view showing the composition of the 1st example applied to the spindle motor of D).

FIG. 2 shows a floppy disk drive (FD)
It is an exploded perspective view showing the composition of the 2nd example applied to the spindle motor of D).

FIG. 3 is a cross-sectional view of the example of FIG.

FIG. 4 is a sectional view of the example of FIG. 2;

FIG. 5 is an exploded perspective view showing a configuration of an example of a conventional bearing device for a rotating body.

FIG. 6 is a cross-sectional view illustrating an example of an FDD spindle motor using the example of FIG. 5;

[Description of Signs] 1 Rotary shaft 2 Bearing 3 Main unit 4 Rotor 5 Flat screw 11 Rotary shaft 12 Bearing 13 Main unit 14 Rotor 15 Flat screw 16 Washer 21 Rotary shaft 22 Bearing 23 Main unit 24 Rotor 25 Flat screw

Claims (1)

(57) [Scope of request for utility model registration] A main body having a rotating shaft, a bearing for supporting the rotating shaft, and a housing for holding the bearing;
A bearing that includes a rotor that imparts rotational motion to the rotating shaft, wherein the bearing is press-fitted such that an upper surface thereof coincides with the upper surface of the main body or slightly lower than an upper surface of the main body. Wherein the diameter of the squeezed portion of the screw fastening portion is larger than the diameter of the bearing.