Fan, motor and oil sealing structure thereof

An oil sealing structure of a motor includes a cover and at least one sealing element. The motor has a shaft, a fluid bearing and a bushing. The fluid bearing mounts to the shaft and is accommodated in the bushing. The cover is disposed around the shaft and is connected with an opening of the bushing. The sealing element is disposed around the shaft and between the fluid bearing and the cover. A fan and a motor including the above-mentioned oil sealing structure are also disclosed.

CROSS REFERENCE TO RELATED APPLICATIONS

This Non-provisional application claims priority under 35 U.S.C. §119(a) on Patent Application No(s). 0961141531, filed in Taiwan, Republic of China on Nov. 2, 2007, the entire contents of which are hereby incorporated by reference.

BACKGROUND OF THE INVENTION

1. Field of Invention

The present invention relates to an oil sealing structure and in particular to an oil sealing structure applied to a fan and a motor.

2. Related Art

The motor is the heart of a fan. In order to keep a motor in smooth and steady as rotating in high speed, a sleeve bearing is employed to support the shaft of the motor in the prior art. The shaft passes through the sleeve bearing. In addition, an oil seal structure is disposed above the sleeve bearing and around the shaft, so that the lubricant can be contained in the sleeve bearing.

However, the oil seal structure is disposed around the shaft, so that the space for containing the lubricant cannot be air-tightly sealed. Therefore, when the motor runs under high speed for a long time, the lubricant will easily leak from the gap between the sleeve bearing and the shaft. If the motor is turned over and still rotates, the lubricant will leak much faster because of the gravity. This will decrease the lubrication between the shaft and the sleeve bearing, Thereby reduce the reliability and lifetime of the motor and the efficiency of the fan.

SUMMARY OF THE INVENTION

In view of the foregoing, the present invention is to provide a fan, a motor and an oil sealing structure that have a sealing element for sealing the lubricant in the fluid bearing to decrease the consumption of the lubricant. In addition, the lubricant absorbed by the sealing element can be released in the fluid bearing to keep the lubrication of the shaft of the motor so as to increase the reliability and the lifetime of the fan and the motor thereof.

To achieve the above, the present invention discloses an oil sealing structure of a motor. The motor has a shaft, a fluid bearing and a bushing. The fluid bearing mounts to the shaft and is accommodated in the bushing. The oil sealing structure includes a cover and at least one sealing element. The cover is disposed around the shaft and connects to one end of the bushing. The sealing element is disposed around the shaft and between the fluid bearing and the cover.

To achieve the above, the present invention also discloses a motor which includes a bushing, a shaft, a fluid bearing and an oil sealing structure. The shaft passes through the bushing, and the fluid bearing is mounted to the shaft and is accommodated in the bushing. The oil sealing structure includes a cover and at least one sealing element. The cover is disposed around the shaft and is connected to one end of the bushing. The sealing element is disposed around the shaft and between the fluid bearing and the cover.

In addition, the present invention further discloses a fan including a motor and an impeller. The motor includes a bushing, a shaft, a fluid bearing and an oil sealing structure. The shaft passes through the bushing, and the fluid bearing is mounted to the shaft and is accommodated in the bushing. The oil sealing structure includes a cover and at least one sealing element. The cover is disposed around the shaft and is connected to one end of the bushing. The sealing element is disposed around the shaft and between the fluid bearing and the cover. The impeller is connected to the shaft, so that the motor can drive the impeller to rotate.

As mentioned above, the fan, motor and oil sealing structure of the present invention utilize a sealing element and a buffer element to form the oil sealing structure of the fluid bearing. The sealing element is disposed between the cover and the fluid bearing of the motor, and the buffer element is disposed between the impeller of the fan and cover. Compared with conventional oil seal structures, the sealing element of the present invention is, for example, made of sponge-like material, so that it can absorb or release lubricant to keep the lubrication state of the shaft. In addition, the buffer element is, for example, made of rubber material to seal the opening of the bushing, so that the leakage of lubricant can be prevented. This can form a secondary protection to keep the lubricant within the fluid bearing efficiently, thereby decreasing the consumption of the lubricant and increasing the reliability and lifetime of the fan and the motor thereof.

DETAILED DESCRIPTION OF THE INVENTION

FIG. 1is a schematic diagram of a fan and a motor thereof according to the preferred embodiment of the present invention.FIG. 2is an enlarged diagram of an oil sealing structure as the portion A ofFIG. 1. Referring toFIG. 1andFIG. 2, a fan1according to the embodiment of the present invention includes an impeller16and a motor10, which drives the impeller16. The motor10includes a bushing11, a shaft13, a fluid bearing14and an oil sealing structure15. The fan1can be an axial-flow fan or a centrifugal fan, and the motor10can be an inner-rotor type motor or an outer-rotor type motor. In this embodiment, the motor10is, for example but not limited to, an outer-rotor type motor of an axial-flow fan.

The motor10has a shaft13passing through the bushing11. A washer17is disposed at the bottom of the bushing11, and the washer17urges against the shaft13for positioning the shaft13. The shaft13passes through the fluid bearing14, and the fluid bearing14is accommodated in the bushing11. In the embodiment, the fluid bearing14can be a sleeve bearing to supply lubrication for the rotating shaft13.

Referring toFIG. 2, the oil sealing structure15has a cover151and at least one sealing element152. The cover151has a ring-shaped trench151aand a ring-shaped flange151b. Herein, the ring-shaped trench151aand ring-shaped flange151bare disposed at opposite sides of the cover151. The cover151can be, for example but not limited to, a lid or a partition. In the embodiment, the cover151is disposed around the shaft13and covers an opening111of the bushing11. The sealing element152is disposed in a space formed by the ring-shaped trench151aand the sealing element152is made of a material capable of absorbing fluids, such as a sponge. In this embodiment, the sealing element152is disposed around the shaft13and located between the fluid bearing14and the cover151. Preferably, the sealing element152urges against one end of the fluid bearing14.

When the fan1and the motor10are turned over, the fluid bearing14can still provide the lubrication for the rotating shaft13. Although the lubricant of the fluid bearing14flows toward the sealing element152due to the gravity, the lubricant is not leaked from the fluid bearing14due to that the sealing element152urges against the end of the fluid bearing14and the wall of the cover151, and that the atmospheric pressure is higher than the inner pressure of the fluid bearing14. In addition, since the sealing element152is made of a sponge-like material, it can absorb the lubricant and the absorbed lubricant can be provided back again to the fluid bearing14, as the arrow shown inFIG. 2.

Referring both toFIG. 1andFIG. 2again, the impeller16has a hub161and a plurality of blades162connected around the hub161. It should be noted that the fan1can further include a buffer element12disposed between the hub161and cover151. For example, the buffer element12is a rubber, and is preferably a ring-shaped rubber disposed at a groove “C” of the inner side of the hub161. The ring-shaped flange151bof the cover151urges against the buffer element12, so that the cover151can be fixed.

When the fan1and the motor10are turned over, the buffer element12, which is disposed at the groove “C” of the inner side of the hub161, can buffer the fan1. In addition, the buffer element12is disposed corresponding to the ring-shaped flange151bof the cover151so as to form the secondary isolation of the lubricant, so that the oil sealing structure15can prevent the lubricant from leaking from the fluid bearing14.

In summary, the fan, motor and oil sealing structure of the present invention utilize a sealing element and a buffer element to form the oil sealing structure of the fluid bearing. The sealing element is disposed between the cover and the fluid bearing of the motor, and the buffer element is disposed between the impeller of the fan and cover. Compared with the related art, the sealing element of the present invention is, for example, made of sponge-like material, so that it can absorb or release lubricant to keep the lubrication state of the shaft. In addition, the buffer element is, for example, made of rubber material to seal the opening of the bushing, so that the leakage of lubricant can be prevented. This can form a secondary protection to keep the lubricant within the fluid bearing efficiently, thereby decreasing the consumption of the lubricant and increasing the reliability and lifetime of the fan and the motor thereof.