JPS59212509A - Dynamic-pressure thrust bearing - Google Patents

Abstract

PURPOSE:To increase the damping action for an impact pressure and lower the temperature on a bearing surface by allowing the front surface and back surface of a bearing piece to communicate and leading the pressure generated on the bearing surface onto the back surface of the bearing, thus floating the bearing piece by a minute gap. CONSTITUTION:The fluid (l) which exists on the periphery of a thrust collar 1 is swallowed-up into a pocket 5 at the center through spiral grooves 7 on the surface of a bearing piece 2, by the revolution of the thrust collar 1, and a pressure is generated. A pressure dam 6 is formed between the back surface of the bearing piece 2 and a concaved part 8 on the surface of a bearing retainer 3. Said bearing piece 2 can be floated-up for the bearing retainer 3, keeping a minute gap 11, by selecting the area of the pressure dam 6 to a proper value. Therefore, the pressurized fluid flows into the pressure dam 6, passing through a communication passage 9 from the pocket 5, and then flows-out through the gap 11, and lowers the temperature on the bearing surface, and the impact is lightened by the throttle action of the gap 11.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a hydrodynamic thrust bearing. Conventional thrust bearings are weak against impact loads, especially when a brittle material such as ceramic is used as the bearing material, and it has been necessary to increase the damping effect of the bearing. Furthermore, when there is almost no oil flow on the bearing surface, there is a tendency for the temperature to rise significantly. In order to eliminate this defect, the present invention has developed a hydrodynamic thrust bearing in which the highest pressure on the bearing surface is guided to a pressure dam part on the back surface of the bearing, and the bearing piece is suspended in a minute gap. The temperature of the bearing surface is reduced by attenuating the impact applied to the bearing surface, and by letting some of the fluid at the highest pressure part of the bearing surface escape through the gap.

To explain the figures, FIG. 1 is a side sectional view of the first embodiment of the present invention, and FIG. 2 is a view taken along the line A-A in FIG.
10 is a vertical shaft, 1 is a thrust collar, 2 is a bearing piece, 3 is a bearing retainer, 4 is a pivot-shaped support that supports the bearing retainer, and 5 is the surface of the bearing piece 2 (that is, the surface facing the thrust collar 1). 7 is a spiral groove leading from the periphery of the bearing piece 2 to the pocket 5, 8 is a recess provided on the surface of the bearing retainer, and 9 is a communication path that communicates the pocket 5 on the bearing piece surface with the back surface of the bearing surface. , and R indicates the direction of rotation of the thrust collar.

Reference numeral 12 designates a bearing case, into which a bearing fluid t is placed.

As the thrust collar 1 rotates, the fluid t existing around it is drawn into the central pocket 5 through the spiral groove 7 on the surface of the bearing piece 2 and generates pressure.

Further, a pressure dam 6 is formed between the back surface of the bearing piece 2 and the recess 8 portion on the surface of the bearing retainer 3. By appropriately selecting the area of the pressure dam, the bearing piece 2 can be floated relative to the bearing retainer 3 with a minute gap (indicated by B in FIG. 1). Reference numeral 11 indicates a gap.

In conventional thrust bearings, the fluid drawn into the pocket 5 has no place to escape, so the temperature of the pocket rises, especially at high speeds and high loads. However, in the device of the present invention, the pressure fluid flows from the pocket 5 through the communication path 9 to reduce the pressure. It goes to the dam B, flows out through the minute gap B, and escapes to the outside, reducing the temperature of the bearing surface. Further, when an impact load or a dynamic load is applied to the thrust bearing surface, the pressure generated on the thrust bearing surface is attenuated by the throttling action in the gap 11, and a damper effect is generated to relieve the load.

Further, in this embodiment, the bearing retainer 3 is attached to a pivot-like support 4.
Since it is supported by and has a centering effect, it is possible to adjust the minute gap B, and the pressure distribution is improved.

FIG. 3 is a side sectional view of a second embodiment of the invention, and FIG. 4 is a view taken along the line C-a in FIG. 6, and FIG.

The same symbols as in FIG. 2 represent the same parts. In this example, unlike the first embodiment, the vertical shaft 10 passes through the bearing. In this example, a pocket 5 on the surface of the bearing piece 2 is provided in an annular shape on the periphery of the shaft 10 passing through the bearing piece 2, and a recess 8 (also formed in an annular shape) on the back surface of the bearing piece 2 and the surface of the bearing retainer 6 is provided. The pressure dam 6 and the pocket 5 are communicated with each other through a communication passage 9. Therefore, the bearing piece 2 has a small gap B
floats up from the bearing retainer 3. The effect is the first
This is exactly the same as the embodiment shown in FIGS.

The dynamic pressure thrust bearing of the present invention has such a configuration, and the front surface and the back surface of the bearing piece are communicated with each other, and the pressure generated on the bearing surface is guided to the back surface of the bearing, so that the bearing piece floats only in a minute gap. As a result, when impact pressure is applied to the bearing, the damping effect of the bearing can be enhanced and the temperature of the bearing surface can be reduced.

[Brief explanation of the drawing]

FIG. 1 is a side sectional view of the first embodiment of the present invention, FIG. 2 is a view taken along arrow 'A-A' in FIG. 1, FIG. 3 is a side sectional view of the second embodiment, and FIG. The a-a arrow view of FIG. 3 is shown, respectively. Explanation of symbols 1...Thrust collar 2...Bearing piece 3...Bearing retainer 4...Support 5...Pocket
6...Pressure dam 7...Spiral groove 8
... Recess 9 ... Communication path 1o ... Vertical shaft 11 ... Minute gap 12 ... Bearing box agent
Patent attorney (81a7) Kiyotaka Sasaki (and 3 others) 11F1 Figure 2 Figure 3 Figure 4WJ

Claims (1)

[Claims] A floating hydrodynamic thrust bearing characterized in that a pressure dam of a desired size is provided on the back surface of the bearing, and the highest pressure part of the bearing surface and the pressure dam on the back surface are connected through a communication path.