JPS63152721A - Bearing - Google Patents

Abstract

PURPOSE:To prevent the seizure of a bearing, by fixing a ceramic support plate between the two-divided surfaces of an oil impregnated sintered body, and bringing the oil existing between them into action in a liquid lubricating condition soon after the rotation of a turning shaft. CONSTITUTION:On both sides of an oil impregnated sintered body 1 in the same direction as a turning shaft 2, cutouts are provided, and further the body 1 is divided into two parts at its center so as to be perpendicular to the turning shaft 2. Between the two surfaces divided into two parts, a ring-shaped support plate 6 whose material is ceramics is insertedly fixed. When the turning shaft 2 starts to rotate, while it is lubricated by the oil between the turning shaft 2 and a support part 7, due to the temperature rise caused by the rotational friction at the support part 7, the oil in the oil impregnated sintered body 1 moves to the support part 7 of the support plate 6. Accordingly, soon after the rotation of the shaft, oil is absorbed into the interior of the oil impregnated sintered body 1 from oil reserving parts 3, and further it is drawn out into the support plate 6, thus the seizure of the bearing can be prevented.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a compact, light-load, sintered, oil-impregnated bearing.

BACKGROUND OF THE INVENTION Conventionally, this type of bearing has generally been constructed as shown in FIGS. 3 and 4. That is, the spherical sintered oil-impregnated body 11
A cylindrical support part 13 provided inside the rotating shaft 12 to support the shaft 12, an end surface 14 formed by cutting parallel to both sides of the sintered oil-impregnated body 11, and an outer surface other than this end surface 14. The spherical surface 16 constituted a bearing. When the rotating shaft 12 rotates, the rotating shaft 12 and the supporting part 13 are in metal contact, and the temperature of the supporting part 13 rises due to frictional heat due to the rotation, and the oil contained in the sintered oil-impregnated body 11 is transferred to the supporting part 13. An oil film is formed between the support portion 13 and the rotating shaft 12, resulting in a state of fluid lubrication. The oil drawn out from the sintered oil-impregnated body 11 is transferred to the support part 13
The oil flows from the oil to the end surface 14, is sucked into the interior of the sintered oil-impregnated body 11 from the end surface 14 and the spherical surface 16, and is further drawn out to the support portion 13, where it is repeatedly circulated for lubrication. and rotation axis 1
When the rotation of the sintered oil-impregnated body 11 stops, the temperature of the sintered oil-impregnated body 11 decreases and the oil returns to the sintered oil-impregnated body 11 to return to its initial state.

Problems to be Solved by the Invention In such a conventional configuration, the oil drawn out from the inside of the sintered oil-impregnated body 11 to the support part 13 flows between the support part 13 and the rotating shaft 12.
The oil flows out to the end face 14 while maintaining a state of fluid lubrication with the end face 14 and is sucked into the sintered oil-impregnated body 11 from the end face 14 and the spherical surface 16. If the amount of oil exceeds the amount of oil sucked from the spherical surface 16, the oil will flow out of the sintered oil-impregnated body 11 and cannot return to the sintered oil-impregnated body 11.
of oil will decrease. If this phenomenon continues, the oil contained in the sintered oil-impregnated body 11 will be extremely reduced, and the metal-to-metal contact state will continue in the support part 3, leading to a seizing state of the bearing and a serious problem. Ta.

The present invention solves these problems by maintaining a good fluid lubrication state without reducing the oil contained in the sintered oil-impregnated body, thereby eliminating seizure of the bearing and preventing serious failure. The object of the present invention is to provide a bearing that can prevent this from occurring.

Means for solving the problem In order to solve this problem, the present invention has a cylindrical hole with a diameter 150 to 300 μm larger than the outer diameter of the rotating shaft,
A spherical sintered oil-impregnated body with planar notches on both sides in the direction of the rotation axis is divided into two perpendicularly to the rotation axis, and a ceramic support plate that contacts and supports the rotation shaft is attached to the sintered oil-impregnated body. It is configured by being fixed between two divided planes.

Effect: With this configuration, the oil present between the ceramic support plate and the rotating shaft is absorbed by the rotation of the rotating shaft, and fluid lubrication is immediately created between the rotating shaft and the support part of the support plate that supports this rotating shaft. Also, since the area between the rotating shaft and the supporting part of the support plate is small, the amount of oil drawn out from the supporting part is reduced, and this drawn oil is distributed between the inner surface of the sintered oil-impregnated body and the rotating shaft. It is retained by capillary action, is sucked into the sintered oil-impregnated body, and drawn out again to the ceramic support, where it is repeatedly circulated and lubricated. Therefore, almost no oil leaks to the end face, and even a small amount of oil that leaks to the end face is sucked into the interior from the end face and the spherical surface, thereby eliminating oil leakage to the outside of the sintered oil-impregnated body.

EXAMPLE An example of the present invention will be described below with reference to FIGS. 1 and 2.

A cylindrical hole with a diameter 160 to 300 μm larger than the outer diameter of the rotating shaft 2 is provided in the inner part of the sintered oil-impregnated body 1 having a spherical outer shape, so that the space between it and the rotating shaft 2 is formed as an oil retaining portion 3. On both sides of the sintered oil-impregnated body 1 in the same direction as the rotation axis 2, a cutout of a planar end face 5 perpendicular to the rotation axis 2 is provided, and the body is further divided into two parts perpendicular to the rotation axis 2 at the center. . An annular support plate 6 made of ceramic is sandwiched and fixed between the two divided surfaces, and the inner diameter of this support plate 6 has a diameter that makes contact with the rotating shaft 2 and supports the rotating shaft 2. The shaft 2 slides on the supporting portion 7.

In the above configuration, since the support plate 6 is not made of a sintered oil-impregnated material, it does not absorb oil, and oil is present between the support portion 7 and the rotating shaft 2 even when the rotating shaft 2 is stopped.

When the rotating shaft 2 starts to rotate in this state, the oil contained in the sintered oil-impregnated body 1 is lubricated by the oil between the rotating shaft 2 and the support part 7, and the temperature rises due to rotational friction in the support part 7. The oil is drawn near the support plate 6 and moves to the support part 7 of the support plate 6. However, since the area of the support portion 7 is narrowed, the amount of oil drawn out is reduced compared to the conventional case. Even if the amount of oil decreases, since the area of the support portion 7 is narrowed, the rotary shaft 2 will rotate in the support portion 7 in a state of fluid lubrication. The oil flowing out from the support part 7 moves to the oil retaining part 3, but since this oil retaining part 3 is a space formed between the rotating shaft 2 and the inner surface of the sintered oil-impregnated body 1, the oil flows through the capillary phenomenon. hold. Then, oil is sucked into the sintered oil-impregnated body 1 from the oil retaining portion 3, and is further drawn out to the support plate 6. This cycle is repeated to provide lubrication. Therefore, almost no oil leaks from the oil retaining part 3 to the end surface 6, but a very small amount of oil still flows out to the end surface 6 and the spherical surface 6.
The oil is sufficiently sucked into the interior of the sintered oil-impregnated body 1, and the oil does not leak out to the outside of the bearing.

As described above, according to this embodiment, since oil exists between the rotating shaft 2 and the support portion 7 even when the rotating shaft 2 is stopped, a fluid lubrication state is established from the beginning of rotation. And the rotating shaft 2 and the support part 7
Since the contact area of the sintered oil-impregnated body 1 is small, the amount of oil drawn out from the sintered oil-impregnated body 1 is reduced.
Since the oil is sucked into the sintered oil-impregnated body 1 from the oil retaining portion 3, almost no oil flows out to the end face 6, and the oil does not decrease.

Effects of the InventionAs is clear from the description of the embodiments above, according to the present invention, even when the rotating shaft is stopped, oil is present between the shaft and the support part,
A state of fluid lubrication occurs from the beginning of rotation, the amount of oil drawn out from the sintered oil-impregnated body is reduced, oil is retained in the oil-retaining part, oil is sucked into the sintered oil-impregnated body, and oil flows to the end face. This eliminates the risk of bearing seizure due to lack of oil, which eliminates problems that could lead to serious failures.

[Brief explanation of the drawing]

FIG. 1 is a side sectional view showing a bearing according to an embodiment of the present invention;
2 is a sectional view taken along the line AA in FIG. 1, FIG. 3 is a side sectional view of the conventional bearing, and FIG. 4 is a front view thereof. 1... Sintered oil-impregnated body, 2... Rotating shaft, 6
・・・・・・Support plate. Name of agent: Patent attorney Toshio Nakatashi and one other person f.-
Figure 2: 1 first surplus, almost 4 books

Claims (1)

[Claims] A spherical sintered oil-impregnated body having a cylindrical hole with a diameter 150 to 300 μm larger than the outer diameter of the rotating shaft inside and having planar notches on both sides in the direction of the rotating shaft is divided into two perpendicularly to the rotating shaft,
A bearing configured by fixing a ceramic support plate that contacts and supports the rotating shaft between two divided surfaces of the sintered oil-impregnated body.