JPH0870552A - Bearing device for vertical shaft type rotating machine - Google Patents

Abstract

(57) [Summary] [Purpose] The oil level is raised by the generation of bubbles in the oil tank,
Prevent oil leakage. [Structure] In the cylindrical bearing 1, pocket-shaped oil reservoirs 2 and 3 are provided at two locations on the upper and lower sides of the inner peripheral surface, and radially extend outward from the oil reservoirs 2 and 3 above and below. An oil drainage hole 4 and an oil supply hole 5 are provided, and an oil drainage adjustment pipe is provided at the outlet of the oil drainage hole 4 on the upper side. The oil drainage hole 2 on the upper side and the oil reservoir 3 on the lower side are connected to each other. Individual oil grooves 6 are provided.

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 vertical shaft type rotating machine.

[0002]

2. Description of the Related Art The structure of a conventional bearing device for a vertical shaft type rotating machine and the flow of lubricating oil will be described with reference to FIG. As shown in FIG. 5, the cylindrical bearing 1 has pocket-shaped oil reservoirs 2 and 3 in two places on the upper and lower sides of the inner peripheral surface, and drains radially extending outward from the oil reservoirs on the upper and lower sides. An oil hole 4 and an oil supply hole 5 are provided, and several oil grooves 6 are provided so as to connect the upper oil reservoir 2 and the lower oil reservoir 3. In this cylindrical bearing 1, the oil sump 3 and the oil supply hole 5 on the lower side are installed so as to be immersed in lubricating oil.

The flow of lubricating oil in the bearing having such a structure is
Due to the viscous pumping effect of the sliding surface of the cylindrical bearing 1 and the collar 7, the lubricating oil is sucked from the oil supply hole 5 and the oil groove 6 and the sliding surface of the bearing 1 and the collar 7 are lubricated via the oil sump 3. The oil is discharged from the oil drain hole 4 via the oil sump 2.

[0004]

In a bearing device for a vertical shaft type rotating machine having a conventional structure, air is introduced from a weir 8 above an upper oil sump 2 of a cylindrical bearing 1 when the rotation speed is high or the temperature of lubricating oil is high. It is sucked and mixed with the lubricating oil in the oil sump 2 and becomes a lubricating oil with many bubbles, which is discharged from the oil drain hole 4, gradually increasing the bubbles of the lubricating oil in the oil tank and raising the oil level 9 to exceed the oil cylinder 10 and the shaft. A large amount of oil leaks from the space between 11 and the oil barrel 10 to the lower side due to the siphon effect 13
Could occur.

The phenomenon of the mechanism of the suction of air into the lubricating oil will be described with reference to the drawings. Phenomenon 1) Pressure of bearing oil sump 2 Lubricating oil pushed up by the bearing viscous pump collects in the oil sump 2 and is discharged from several oil discharge holes 4 extending radially from the oil sump 2. As for the inside pressure distribution, as shown in FIG. 6, the pressure is higher as it is farther from the oil drain hole 4, and the pressure is lowest at the oil drain hole 4. The pressure in this oil sump 2 is
The higher the rotational speed of the collar 7, the higher the color. Since the portion of the oil drain hole 4 is a portion where the pressure is released, the pressure becomes higher as it goes farther to the oil drain hole 4.

Here, if the collar 7 is rotating without eccentricity, the pressure in the oil sump 2 is positive at any part, so that lubrication to the outside also occurs between the weir 8 and the collar 7 at the upper part of the bearing 1. The oil is discharged, air is not sucked from the weir 8, and no bubbles of lubricating oil are generated. Phenomenon 2) Pressure between weir 8 and collar 7 On the other hand, since the collar 7 is actually eccentric to the sliding surface of the bearing 1 to rotate (rotate), and the bearing load is small due to the vertical axis type,
It swings around the inner surface of the bearing. At this time, the pressure distribution between the weir 8 and the collar 7 is "A" as shown in FIGS.
In the portion, the pressure is high (positive pressure) in the compression portion, and in the portion "B", the compression is released and the pressure is low (negative pressure).

The pressure difference between the "A" portion and the "B" portion increases as the number of rotations of the collar 7 increases. Event 3) Mechanism of suction of air into oil sump 2 Event 2) shows the upper part of oil sump 2 of the pressure distribution described in event 1).
When the pressure distribution described in (4) moves around whirling of collar 7, when the low pressure "B" part of event 2) comes to the low oil drain hole 4 of event 1), that part becomes negative pressure. , Cough 8
Air is sucked in between the gap and the collar 7 to generate bubbles in the lubricating oil in the oil sump. Since the negative pressure in the "B" portion increases as the rotation speed increases, the amount of air taken in also increases and the bubbles in the lubricating oil also increase.

Further, when the temperature of the lubricating oil becomes high, the viscous pump effect in the event 1) is weakened and the overall positive pressure level is lowered, and the event 2) is obtained even when the rotation speed is not increased.
Due to the effect of, a negative pressure is partially generated and air is sucked.

Accordingly, it is an object of the present invention to provide a bearing device for a vertical shaft type rotating machine configured to prevent the formation of bubbles in an oil tank even at high speed rotation and when the temperature of lubricating oil is high. To do.

[0010]

In order to achieve the above object, the present invention relates to a cylindrical bearing of a vertical shaft type rotating machine, and an oil sump over the entire circumference at two places on the upper side and the lower side of the inner peripheral surface. Several holes radially extending from the oil sump are provided, and several oil grooves are provided in the longitudinal direction so as to connect the oil sumps provided on the inner peripheral surface, and the oil surface of the lubricating oil is the oil An oil drainage adjustment pipe is installed at the outer peripheral outlets of several holes arranged radially between the oil reservoirs provided on the upper side and radially extending from the oil reservoirs.

[0011]

In the present invention thus constructed, the area of the oil discharge port of the oil discharge adjusting pipe is changed to a small value and the flow rate of the oil discharge is reduced in accordance with the number of rotations of the rotating machine, whereby Increase the pressure in the oil drain hole of the and to even out the pressure in the oil sump. As a result, even if the negative pressure of the "B" portion of the above-mentioned event 2 is applied to the oil drain hole portion of the above-mentioned event 1, the pressure there can be maintained at a positive pressure, and the air into the oil sump can be maintained. It is possible to prevent the generation of bubbles of lubricating oil by eliminating the suction of oil.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. As shown in FIG. 1 to FIG. 3, the cylindrical bearing 1 has pocket-shaped oil reservoirs 2 and 3 and two upper and lower oil reservoirs over the entire circumference on the upper side and the lower side of the inner peripheral surface. 2, 3 are provided with oil drain holes 4 and oil filler holes 5 extending radially outward, and an oil drain adjusting pipe is provided at the outlet of the oil drain hole 4 on the upper side, and an oil sump 2 on the upper side. Several oil grooves 6 are provided so as to connect the oil reservoir 3 on the lower side.

In this cylindrical bearing 1, the oil sump 3 and the oil supply hole 5 on the lower side are installed so as to be immersed in lubricating oil. The lubricating oil of the bearing device thus configured is sucked from the oil supply hole 5 by the viscous pumping effect of the sliding surface of the cylindrical bearing 1 and the collar 7, and passes through the oil sump 3 to the oil groove 6 and the bearing 1 and the collar 7. The sliding surface of the oil is lubricated and is discharged from the oil drain hole 4 via the oil sump 2, but the oil drain port area of the oil drain adjustment pipe installed at the outlet of the oil drain hole 4 is changed slightly according to the number of revolutions. By reducing the amount of lubricating oil discharged, the pressure in the oil sump 2 can be increased and the pressure in the oil sump can be increased and averaged as shown in FIG.

According to the configuration of the embodiment described above, since the pressure in the oil sump 2 can be increased, the cough 8 is obtained even when the rotation speed is high and the temperature of the lubricating oil is high and the effect of the viscous pump is low. It is possible to prevent bubbles from being generated in the lubricating oil without sucking air from between the collar 7 and the collar 7.

FIG. 4 shows the results of measurement of the specific gravity of the lubricating oil in the oil tank when the discharge amount of the lubricating oil was reduced according to this embodiment and when the conventional structure was used. In the conventional case, the specific gravity of the lubricating oil continues to decrease with time, which means that the bubbles in the lubricating oil continue to increase.

According to this embodiment, when the discharge amount is narrowed down, it is 1
The specific gravity hardly changes with time. This means that air did not enter the lubricating oil and no bubbles were generated.

[0017]

As described above, according to the present invention, it is possible to prevent an oil leak in a bearing device of a vertical shaft type rotating machine used under any condition by raising bubbles in the oil tank due to generation of bubbles. It is possible to provide a highly reliable bearing device for a vertical shaft type rotating machine.

[Brief description of drawings]

FIG. 1 is a sectional view of a bearing device for a vertical shaft type rotating machine according to an embodiment of the present invention.

2 is a development view of a bearing sliding surface in the embodiment shown in FIG.

FIG. 3 is a pressure distribution diagram of the upper oil sump portion of the embodiment shown in FIG.

FIG. 4 is a graph showing the results of measuring the specific gravity of the lubricating oil in the oil tank in the bearing device according to the embodiment shown in FIG. 1 and the conventional bearing device.

FIG. 5 is a sectional view of a conventional bearing device for a vertical shaft type rotating machine.

6 is a pressure distribution diagram of an upper oil sump portion of the conventional bearing device shown in FIG.

FIG. 7 is a plan view and a pressure distribution diagram of a bearing upper weir of the conventional bearing device shown in FIG.

8 is a pressure distribution chart of the bearing upper weir of the conventional bearing device shown in FIG.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Cylindrical bearing, 2, 3 ... Oil sump, 4 ... Oil discharge hole, 5 ... Oil supply hole, 6 ... Oil groove, 12 ... Flow control device, 14 ... Oil discharge port.

Claims (1)

[Claims] 1. A cylindrical bearing of a vertical shaft type rotating machine is provided with an oil sump at two locations on the upper side and the lower side of the inner peripheral surface, and several holes radially extending outward from the oil sump, and A plurality of oil grooves are provided in the vertical direction so as to connect the oil reservoirs provided on the inner peripheral surface, the oil surface of the lubricating oil is disposed between the oil reservoirs, and the oil provided on the upper side A bearing device for a vertical shaft type rotating machine, wherein an oil drainage adjustment pipe is installed at the outer peripheral outlets of several holes radially extending from the pool.