JPH1113749A - Dynamic pressure plane bearing - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enable a dynamic pressure plane bearing to be used for the use rotating both directions of normal rotation and reverse rotation by forming dynamic pressure generating parts of which each combines a pair slopes to be in right and left symmetric slope directions against rotating direction with a horizontal plane on either the underside of an upper cylindrical ring or the upper face of the bottom part of an annular oil tank opposite to each other. SOLUTION: In a dynamic pressure plane bearing used for the place rotating in a horizontal plane and supporting vertical load such as the rotary surface plate of a surface lapping machine, slopes on the underside of a cylindrical ring 7 are symmetrically provided in the lowering directions from both ends of horizontal planes 12. A slitting 13 for working the slope is provided on the lower end of the slope 11, and beyond it the lower end part of the next slope 11 is arranged. By arranging a plurality of, for example, the six horizontal planes 12 and the respective six pairs of slopes 11 alternately slanting in the opposite directions in this way, even in the case of rotating normally or reversely, flow of lubricating oil is squeezed by the slopes 11, and hence maximum dynamic pressure can be generated in the horizontal planes 12.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a dynamic pressure bearing used in a place for supporting a vertical load rotating in a horizontal plane, such as a rotary platen of a flat lapping machine.

[0002]

2. Description of the Related Art Conventionally, a dynamic pressure plane bearing used for a plane lapping machine is constructed as shown in FIGS.
That is, an oil tank 3 having an annular groove is provided on the upper surface of the bearing base 1 (base) of the machine. The oil tank 3 contains a lubricating oil 4 (a viscous fluid). The groove bottom 5 in the oil tank is formed in a horizontal plane. A cylindrical ring 7 is used as a thrust bearing for supporting a lower lap disk receiver 6 of a flat lapping machine. The cylindrical ring 7 has a width slightly smaller than the groove width of the oil tank 3, is inserted into the oil tank 3, floats on the lubricating oil 4, and is configured to be able to freely rotate horizontally in the oil tank 3. ing. The lower wrap disk receiver 6 is placed on the upper surface of the cylindrical ring 7 and is integrally connected to each other by, for example, mounting screws. Next, on the lower surface 10 of the cylindrical ring 7, for example, 6
Six slopes 11 equally divided and having a certain direction to each other
Is provided. Note that these slopes 11 are inclined with respect to the horizontal plane, the rotation direction a of the lower lap disk receiver 6 is higher than the groove bottom 5, and the opposite side to the rotation direction a is relative to the groove bottom 5. It has a slope that decreases. By the way, this slope 11 has a cylindrical ring 7 indicated by an arrow a.
This is a very important factor for floating the cylindrical ring 7 from the groove bottom 5 when rotating in the direction, and is related to the rotational speed of the lower wrap disk receiver 6, the viscosity of the lubricating oil 4, and the like. It is usually designed with an inclination angle of 2 to 3 °. Reference numeral 12 denotes a horizontal plane provided at the lower end of the slope 11, and reference numeral 13 denotes a cut formed when processing each slope. According to the dynamic pressure plain bearing 14 configured as described above, when the lower lap disk receiver 6 is first stopped, as shown in FIG. Is in contact with the groove bottom 5. Next, as shown in FIG. 11, the lower wrap disk receiver 6 is driven to rotate in the direction of arrow a, and when the cylindrical ring 7 rotates integrally with the lower wrap disk receiver 6 in the same direction, it adheres to the inclined surface 11 of the rotated cylindrical ring 7. The lubricating oil 4 is drawn into the narrow wedge-shaped gap 16 formed between the slope 11 and the horizontal groove bottom 5 in the direction opposite to the direction of the arrow a, and at this time, hydraulic pressure is generated. Then, the cylindrical ring 7 is given a levitation force by the hydraulic pressure, maintains an appropriate gap 16 between the horizontal surface 12 and the groove bottom 5, and maintains a horizontal state.
Mechanically supported in a completely non-contact state. Then, the cylindrical ring 7 rotates extremely stably without generating vertical vibration or surface runout. The higher the rotation speed of the cylindrical ring 7 is, the higher the oil pressure is, the more the stability is increased, and the above-mentioned vibration and runout are further reduced. Therefore, similarly to the cylindrical ring 7, it is driven at extremely high speed and very stably without any vibration or runout. In addition, the dynamic pressure that acts as the bearing force is self-generated by rotation, so there is no need for a separate pressure source, such as a pump, unlike a bearing that uses static pressure. Low in nature.

[0003]

However, as described above, the bearing force of the present bearing is, as shown in FIG. 11, the hydraulic pressure generated by the hydraulic effect of the slope 11 cut into the lower surface 10 of the cylindrical ring 7. , But
Since the slope 11 is formed only in one direction, the hydraulic effect occurs only when the cylindrical ring 7 rotates in the direction of arrow a, but does not occur when the cylinder ring 7 rotates in the opposite direction. In this case, since the bearing cannot be rotated in the reverse direction, there is a possibility that the bearing cannot be used depending on the application of the machine. Therefore, an object of the present invention is to provide a dynamic pressure plane bearing that functions as a bearing without any trouble by generating dynamic pressure even when the bearing is reversed.

[0004]

In order to solve the above-mentioned problems, the invention of claim 1 is to provide a slope and a horizontal surface on one of the lower surface of the upper cylindrical ring and the upper surface of the bottom of the lower annular oil tank. In a dynamic pressure generating bearing in which the combined dynamic pressure generating portions are formed at appropriate intervals, a dynamic pressure generating portion is formed by combining a pair of slopes and a horizontal surface that are symmetrically inclined with respect to the rotation direction. Enable rotation.

[0005]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a bottom view of the cylindrical ring, and FIG. 2 is a view taken along the line AA in FIG. The cylindrical ring shown in FIG. 1 is obtained by modifying the bottom portion of the cylindrical ring in the conventional dynamic pressure bearing shown in FIGS. 3 to 11, and the entire dynamic pressure bearing is the same as the conventional one. Therefore, illustration and description of the entire bearing are omitted. Hereinafter, the cylindrical ring portion will be described. In this embodiment, as shown in FIGS. 1 and 2, the lower surface 10 of the cylindrical ring 7
The slope 11 is provided symmetrically in a direction lowering from both ends of the horizontal plane 12, a cut 13 is provided at the lower end of the slope 11 for slope processing, and the lower end of the slope 11 is separated from the notch 13. I have. With the configuration of the six horizontal surfaces 12 and the six inclined surfaces 11 alternately inclined in the opposite directions in this manner, the flow of the lubricating oil is narrowed down by the inclined surfaces 11 in both forward and reverse rotations. 12, a maximum dynamic pressure can be generated to give a levitation force.

In the above-described embodiment, the inclined surface and the horizontal surface are formed on the bottom surface of the cylindrical ring. However, the inclined surface and the horizontal surface are similarly formed alternately on the upper surface of the bottom portion of the lower annular oil tank. It is also possible.

[0007]

As described above, according to the first aspect of the present invention, a dynamic pressure generating portion is formed by a pair of inclined surfaces having symmetrical inclination directions, so that dynamic pressure is generated even in the case of reverse rotation. Because the load can be supported, it can be used in applications that rotate in both forward and reverse directions.

[Brief description of the drawings]

FIG. 1 is a bottom view showing a main part of an embodiment of the present invention.

FIG. 2 is a view as viewed in the direction of arrows AA in FIG. 1;

FIG. 3 is a longitudinal sectional view showing a conventional example.

FIG. 4 is a plan view showing a conventional example.

FIG. 5 is a perspective view showing a conventional example.

FIG. 6 is a perspective view showing a conventional example.

FIG. 7 is a bottom view showing a conventional example.

FIG. 8 is a sectional view showing a conventional example.

FIG. 9 is a plan view showing a conventional example.

FIG. 10 is a sectional view showing a conventional example.

FIG. 11 is a sectional view showing a conventional example.

[Explanation of symbols]

 7 Cylindrical ring 10 Lower surface 11 Slope 12 Horizontal surface 13 Notch

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Minoru Tsukui 5-5-15 Nishigotanda, Shinagawa-ku, Tokyo Inside Hamai Industry Co., Ltd.

Claims (1)

[Claims] 1. A dynamic pressure plane bearing in which a dynamic pressure generating portion formed by combining a slope and a horizontal surface is formed at an appropriate interval on one of an opposing lower surface of an upper cylindrical ring or an upper surface of a lower portion of a lower annular oil tank. A dynamic pressure generating portion formed by combining a pair of inclined surfaces having a symmetrical inclination direction with respect to the horizontal surface and a horizontal surface.