JPH089458Y2 - Sintered oil-impregnated bearing surrounding support structure - Google Patents

Description

[Detailed Description of the Invention] [Field of Use of the Invention] The present invention relates to a heat generation prevention structure for a bearing of a device such as an orbital sander that generates dust.

[Background of the invention]

Figure 1 shows the appearance of a typical orbital sander.
FIG. 3 shows the internal structure of a conventional orbital sander.
The conventional technique will be described with reference to FIGS. 1 and 3. 1 is a rotor of a motor, and the rotor 1 is an upper sintered oil-impregnated bearing 2
It is rotatably supported by an outer frame 4 made of a resin material via a ball bearing 3 on the lower side. Rotor shaft 5
A polishing plate 6 is attached to the lower end of the so that it can slide in the horizontal direction by the high speed rotation of the rotor 1. In this type of orbital sander, sandpaper 7 can be attached to the lower surface of the polishing plate 6, and the sliding motion of the polishing plate 6 can polish a work material such as wood.

By the way, a fan 8 is attached to the rotor 1 so as to suck the atmosphere from the intake window of the outer frame 4 and blow it out from the exhaust window 10 to cool the motor and burn a part of the intake air. The sintered oil-impregnated tray 2 is cooled by being applied to the lower end surface of the oil-impregnated bearing 2. Further, the bearing chamber 12 of the outer frame 4 has an outer periphery in order to prevent the impregnated oil from flowing out from the outer surface of the sintered oil-impregnated bearing 2.
Although it surrounds 13 and the upper end surface 14, the lower end surface 11 side has an opening 15 for cooling the sintered oil-impregnated bearing 2.

In this structure, since the open portion 15 is provided in the bearing chamber 12 on the lower end surface 11 side of the sintered oil-impregnated bearing 2, the atmosphere containing dust generated when polishing wood or the like is sucked into the inside of the machine body, By hitting the lower end surface 11 of the sintered oil-impregnated bearing 2 partially,
Dust will gradually adhere to the lower end surface 11 of the sintered oil-impregnated bearing 2. When dust adheres to the lower end surface 11 of the sintered oil-impregnated bearing 2,
The impregnated oil of the sintered oil-impregnated bearing 2 is rapidly absorbed by dust, and the sintered oil-impregnated bearing 2 is in a non-supply state, so that the sintered oil-impregnated bearing 2 rapidly generates heat and melts the bearing chamber 12 of the outer frame 4. As described above, there is a drawback that the machine body is damaged before the predetermined life of the sintered oil-impregnated bearing is reached. Further, in order to avoid this drawback, the use of a ball bearing with a seal or the like is inevitable, and there is a drawback that the machine body becomes expensive.

[Purpose of device]

The object of the present invention is to eliminate the above-mentioned drawbacks of the prior art,
The object of the present invention is to extend the service life of devices that generate this type of dust and to provide low-priced devices.

[Outline of device]

The present invention encloses the outer surface of the sintered oil-impregnated bearing with a material having good thermal conductivity and is not porous, so that the heat dissipation of the sintered oil-impregnated bearing is not lost and the impregnated oil flows out from the outer surface of the sintered oil-impregnated bearing. In order to prevent impregnated oil from effectively flowing out from the inner peripheral surface of the sintered oil-impregnated bearing when the rotor rotates, the relationship between the sintered oil-impregnated bearing, the bearing chamber, and the washer is devised.

[Example of device]

Figure 1 shows the appearance of a typical orbital sander.
FIG. 2 shows the internal structure of an orbital sander to which the sintered oil-impregnated bearing surrounding support structure of the present invention is applied. This will be described with reference to FIGS. 1 and 2.

Rotor 1, which is each part as an orbital sander,
Regarding the structure and function of the sintered oil-impregnated bearing 2, the ball bearing 3, the outer frame 4, the rotor shaft 5, the polishing plate 6, the sandpaper 7, the fan 8, the intake window 9, and the exhaust window 10, see “3. It is the same content. Further, the point that the bearing chamber 12 surrounds the outer circumference 13 and the upper end surface 14 of the sintered oil-impregnated bearing 2 in order to prevent the impregnated oil from flowing out is also the same as in 3. Prior Art. However, between the lower end surface 11 of the sintered oil-impregnated bearing 2 and the open portion 15 of the bearing chamber 12, the same shape as that of the lower end surface 11 of the sintered oil-impregnated bearing 2 is used, such as a metal plate of a welded material. A washer 16 having good conductivity and made of a non-porous material is inserted in close contact with the lower end surface 11 of the sintered oil-impregnated bearing 2.

In the above configuration, the fan 8 can be used to blow the atmosphere containing dust.
Is sucked through the intake window 9 by high speed rotation, and a part of the suction is applied to the lower surface 17 of the washer 16 to cool the washer 16. Since the washer 16 is a material with good thermal conductivity, the washer 16
As a result, the sintered oil-impregnated bearing can be cooled in the same manner. Dust gradually adheres to the lower surface of the washer 16, but since the washer 16 is not a porous material, the impregnated oil of the sintered oil-impregnated bearing 2 does not pass through it, but is rapidly absorbed by the dust adhered to the lower surface 17 of the washer 16. It will not be done.

[Effect of device]

According to the present invention, the sintered oil-impregnated bearing is provided with the washer made of a non-porous material on the open surface of the sintered oil-impregnated bearing, so that the sintered oil-impregnated bearing can be cooled and the impregnated oil can be absorbed by the dust. Therefore, the life of the sintered oil-impregnated bearing can be extended at a low cost.

[Brief description of drawings]

FIG. 1 is a perspective view showing the appearance of a general orbital sander, FIG. 2 is a vertical sectional view of an orbital sander to which a sintered oil-impregnated bearing surrounding support structure according to the present invention is applied, and FIG. 3 is a conventional orbital sander. FIG. In the figure, 1 is a rotor, 2 is a sintered oil-impregnated bearing, 3 is a ball bearing, 4 is an outer frame, 5 is a rotor shaft, 6 is a polishing plate,
7 is sandpaper, 8 is a fan, 9 is an intake window, 10 is an exhaust window, 11 is a lower end surface, 11 is a lower end surface, 12 is a bearing chamber, 13 is an outer periphery, 14 is an upper end surface, 15 is an open portion, 16 is a washer, 17 is a lower surface. Is.

Claims (1)

[Scope of utility model registration request] 1. An outer surface of a sintered oil-impregnated bearing is surrounded and supported by a resin material, and the resin material is opened at least at one end surface side of the sintered oil-impregnated bearing, and a slight wind blows on the open surface of the sintered oil-impregnated bearing. In the structure for cooling the sintered oil-impregnated bearing by applying the above, a washer made of a non-porous material having the same shape as that of the open surface of the sintered oil-impregnated bearing and having good thermal conductivity is attached to the open surface. Sintered oil-impregnated bearing surrounding support structure characterized by: