JPS6252215A - Intermediate plate of spiral groove bearing - Google Patents

Abstract

PURPOSE:To avoid an error in work at the time of installing an intermediate plate by mirror-finishing the surface of a projecting portion similarly to a convex portion adjacent to a spiral groove to indicate a mark. CONSTITUTION:A spiral form is placed on the surface of an intermediate plate, and a photo mask is superposed at the central portion 2 thereof. Subsequently, a spiral groove 1 and a circular concave portion of the central portion is shaved off, with a mark portion left. Accordingly, the surface of the projecting portion of the central portion and the surface of the convex portion adjacent to the spiral groove keep smooth surfaces, so that the indication of a mark on the projecting portion can be clearly recognized to avoid an error in work at the time of installing the intermediate plate.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an intermediate plate of a spiral group bearing that utilizes the dynamic pressure effect of a fluid.

[Prior art] One of the two planes forming the sliding part is made smooth, and a groove is formed on the other surface, and the relative movement of these two planes causes the inside of the sliding part to flow. Snow bearings, which generate dynamic pressure in fluids, have been proposed for a long time.

In early spiral group bearings, spiral grooves were formed directly on either the surface of the rotating shaft end member or the fixed sliding member disposed opposite thereto.

However, the groove depth in the rotating shaft end member and fixed side sliding member is 3~3.
It was an extremely difficult technique to perform extremely precise processing of 50 μm.

The inventors of the present invention have filed Japanese Patent Application No. 58-154475
-2681a], a disk-shaped hard member with grooves formed on both planes is inserted between a plane perpendicular to the axis of the rotating shaft end member and a plane of the stationary side member opposite to this plane. We proposed a new spiral group bearing.

Spiral group bearings using this intermediate plate are
It was subsequently tested by Yamaban et al. and was reported to have excellent functionality despite its simple structure.

To give an overview of the spiral group bearing proposed by the present inventors, which uses a disk-shaped hard member with spiral grooves formed on both planes as an intermediate plate, the end face of the shaft end member of the rotating shaft is placed in a plane perpendicular to the rotating shaft. The end of the stationary member facing this plane is also a smooth plane, and a disk made of ceramics, hard sintered metal, etc. is interposed between them as an intermediate plate. Both sides of the plate have a mirror finish with a surface roughness of 0.Sμm or less, and a plurality of (for example, 15) spiral grooves are formed from the outer edge of the intermediate plate toward the center. A circular concave portion having a depth similar to that of the spiral groove (3 to 50 μm) is provided.

FIG. 9 is a diagram showing the state of the spiral groove 1 and the central part 2 of this intermediate plate, and shows the spiral groove 1 in the annular region of the curve between the inner peripheral edge 5 and the outer peripheral edge 4 of the spiral groove 1 and the adjacent spiral groove 1. In this example, the area ratio with the convex portion 5 is approximately 1:1. Further, in the central portion 2, a circular recessed portion having the same depth as the spiral groove is formed.

Furthermore, spiral grooves in the opposite direction to those shown in FIG. 9 are similarly formed on the surface opposite to that shown in FIG. 9, and the same is true for the central portion.

The spiral groove 1 and the central portion 2 are 6
~50μm deeper. When the rotating shaft is rotated in the direction of arrow A with the fluid being opposed to the plane of the end surface of the spiral groove material shown in FIG. Since a force is generated that flows along the axis toward the center part 2, a large dynamic pressure is generated between the end of the rotating shaft and the intermediate plate in which the spiral groove 1 is formed, and the rotating shaft resists the large thrust force. It can rotate with extremely little sliding resistance.

In this state, the surface of the intermediate plate opposite to the surface of the intermediate plate shown in FIG. 9 faces the plane of the fixed side member, and the fluid existing between them is pushed out from the center toward the outer periphery. Therefore, an adsorption force is generated, and as a result, the intermediate plate is fixed to the fixed side member.

In addition, when the rotation direction of the rotating shaft is reversed, the intermediate plate is fixed to the end of the rotating shaft end member for the same reason, and a sliding part is formed between the plane of the fixed side member and the intermediate plate. becomes. In this type of spiral group bearing, the intermediate plate is preferably made of a hard member such as ceramic or hard sintered gold ingot.

[Problem that the invention seeks to solve]

Spiral group bearings using an intermediate plate generally use ceramics (SIC, 81.N) as the intermediate plate.
4. Alumina, etc.), hard sintered metal (cemented carbide, etc.), graphite, etc. are used, and the surface is 0.3 μm.
A smooth mirror finish within 3 to 50 pm depth.
Since the process involves forming spiral grooves of approximately 100 degrees, the process is often different from the manufacturing process for other parts than the intermediate plate, such as rotating shafts, fixed side members, or mechanical parts connected thereto.

Therefore, the intermediate plate is a factory (process) that specializes in manufacturing intermediate plates.
When assembling the bearing part, the completed intermediate plate will be installed there.

Further, during periodic inspection of the bearing portion or when the intermediate plate is damaged, only the intermediate plate may be replaced.

As described above, when attaching the intermediate plate to the bearing part, it is difficult to confirm the dimensions and functions of the intermediate plate, which is extremely inconvenient for the user. At the same time, because the intermediate plate was made of the wrong material or had the specified thickness, the desired performance could not be achieved, or the life of the bearing or equipment could be shortened.

[Object of the Invention] The present invention provides a display that specifies the dimensions, functions, etc. of the intermediate plate of a spiral group bearing, thereby reducing the friction when installing the intermediate plate.

In addition, in the present invention, without providing any special process,
The intermediate plate can be marked with such markings, and the function of the spiral group bearing is not substantially deteriorated.

[Structure of the invention]

The intermediate spiral group bearing of the present invention has one or more sheets between a plane perpendicular to the axis of the rotating member provided at the end of the rotating shaft and a plane of the stationary member opposite to this plane. In an intermediate plate of a spiral group bearing including an intermediate plate made of a disk-shaped hard member with spiral grooves formed therebetween, a plurality of spiral grooves are formed in a plane of the intermediate plate from the outer peripheral edge toward the center, The central part of this plane is a circular recess having a depth substantially equal to that of the spiral groove, and a symbol specifying the function of the intermediate plate having a height equal to the surface of the protrusion adjacent to the spiral groove is placed in the recess. It is provided with a protrusion to be formed.

[Effect]

- In the intermediate plate of the present invention, a spiral groove that generates a dynamic pressure effect is formed on the outer peripheral edge of the intermediate plate, and a symbol specifying the function of the intermediate plate is formed in the center of the intermediate plate, so that the rotation axis When rotating, fluid dynamic pressure can be effectively generated on the outer peripheral edge side where the relative velocity is large.
In addition, the relative velocity between the opposing planes of the central protrusion, which does not directly contribute to the dynamic pressure effect, is smaller than that of the spiral groove, so it has little effect on the dynamic pressure effect of the entire surface of the intermediate plate. Become something.

Further, since the height of the central protrusion is the same as that of the protrusion adjacent to the spiral groove, there is no problem that only this protrusion directly contacts the opposing plane.

[Example 1] Fig. 1 shows an embodiment of the present invention, in which the outer diameter dimension 6, the plate thickness 7, and the rotation direction 8 of the intermediate plate are placed in the circular recess at the center of the intermediate plate shown in Fig. 9. is indicated by the protrusion (ts, 7.8
), and the concave portion at the center of this back surface is not indicated by the protrusions at the center portion 2.

In the embodiment shown in FIG. 1, it is sufficient to mount it with the illustrated surface facing the (b) end of the rolling shaft, and the amount of mounting Z is significantly reduced.

In addition, the processing of the protrusions 6, 7.8 on the central part 2 of the intermediate plate is as follows:
This was done at the same time as forming the spiral groove 1.

That is, the front and back surfaces of an intermediate plate made of, for example, 810 processed to a predetermined diameter and thickness are processed to a mirror finish of 0.3 μm or less, and a spiral shape is formed on the surface and a first
Seven otomasks with the symbol 6° 7.8 as shown in the figure are stacked one on top of the other, and then the spiral groove 1 and the circular concave portion of the central portion 2 are removed by about 6 to 50 μm, leaving the part marked with the symbol, using shot blasting. Then, when the photomask is removed, the surface of the protrusion in the center and Table 1ii of the protrusion adjacent to spiral #12 show that the smooth surface before shot blasting is preserved, and the symbols for the protrusion are Can be clearly identified.

The processing method using this photomask is described in Japanese Patent Application Laid-open No. 6
This was proposed by the present inventors as Publication No. 0-14615.

[Embodiment 2] Fig. 2 shows an example in which the present invention is applied to the conventional example shown in Fig. 9. In the embodiment shown in Fig. 2, the protrusion 8 formed in the central portion 2 is formed in the spiral groove of the intermediate plate. It is formed so as to be symmetrical with respect to the center point 9 of the plane on which it is formed.

In this embodiment, the only indication by the central protrusion 8 is an arrow 8 indicating the direction of the rotation axis, but in this case, the rotation center 9 of the intermediate plate coincides with the center point of the dynamic pressure effect, so the rotation of the rotation axis It is suitable when the speed is high and the intermediate plate is fixed (adsorbed) to the rotating shaft.

[Embodiment 3] FIGS. 3, 4, 5, 6, 7, and 8 are other embodiments of the present invention, in which two sheets of This is an embodiment of a spherical group bearing using an intermediate plate formed by combining discs 10 and 11 with small balls 12 therebetween.

FIG. 3 is a front view of the outer surface of the upper intermediate plate 10 facing the end surface of the rotating shaft. Part 2
An arrow t3.13' indicating the direction of rotation of the rotating shaft to be mounted symmetrically with the center point 9 is indicated by a protrusion.

FIG. 4 is a front view of the outer surface of the lower intermediate plate 11, which faces the end face of the fixed side member, and the lower intermediate plate 11 is attracted to the fixed side member by rotation of the rotating shaft. There is something out there.

△ Therefore, the upper intermediate plate 10 is attracted to the end face of the rotating shaft, and the lower intermediate plate 11 is attracted to the fixed side member, so the upper intermediate plate 1
0 and the lower intermediate plate 11, a sliding portion is formed.

As shown in FIG. 4, the central part 2 of the outer surface of the lower intermediate plate 11
The outer diameter dimension, thickness, and number of spiral grooves on the back surface are respectively "D 81←,"t 4■", and "(n==c1
5) Indicated by J and protrusion.

In the intermediate plate shown in FIGS. 5 to 8, since the upper intermediate plate 10 rotates together with the rotating shaft, the projections 15 formed on the four central parts 2 surrounded by the spiral grooves of the upper intermediate plate 10 .15' is designed to maintain balance even during high-speed rotation, and other necessary indications are displayed by providing protrusions on the outer surface of the lower intermediate plate 11.

Therefore, in this embodiment, small balls 12 are arranged in hemispherical recesses 15 and 14 provided at the center between the upper intermediate plate 10 and the lower intermediate plate 11, and lubricating oil or water is attached to the spheres 12. Upper and lower intermediate plates 10. Once the upper and lower intermediate plates were joined together, it was difficult to separate the upper and lower intermediate plates υ by normal means, and its internal structure was completely unknown, but the number of spiral grooves was indicated on the outer surface of the lower intermediate plate 11. This makes it easy to judge.

In addition, FIG. 5 shows the inner surface of the upper intermediate plate 10, FIG. 6 shows the inner surface of the lower intermediate plate, and FIG. 8 shows an enlarged cross-sectional view of FIG. 7.

〔Effect of the invention〕

Since the intermediate plate of the present invention has a spiral groove formed on the outer peripheral edge side of the intermediate plate as described above, the dynamic pressure generated by the rotation of the rotating shaft is extremely large, and the protrusion formed in the center Since the relative speed with the plane facing the disk is small, even if the shape of the protrusion, that is, the pattern, is asymmetrical with respect to the center of the disk, the overall balance will be lost in terms of the dynamic pressure effect. There isn't.

Furthermore, even when the intermediate plate rotates, the thickness of the intermediate plate is usually 1- or more, so the thickness of the central part is 3 to 50 μm.
Since the center of gravity moves very little due to the protrusions, vibrations do not become intense. Regarding the protrusion formed in the center of the intermediate plate, its surface is at the same height as the protrusion adjacent to the spiral groove, so that only the surface of the protrusion is in solid contact with the opposing plane. There are no problems, and since the dynamic pressure generated by the spiral groove is transmitted by fluid on the surface of the protrusion, the presence of the protrusion does not impede the dynamic pressure effect.

Furthermore, the surface of the protrusion has a mirror finish (0°5 μm or less) with the same surface roughness as the convex part in contact with the spiral groove fi:H, so it is significantly smoother than the surface roughness of the four parts.
The symbol display is clearly visible.

Further, if the functions such as the dimensions, material, groove shape, rotation direction, etc. of the intermediate plate are displayed in this way, errors in work when attaching the intermediate plate to the bearing portion can be eliminated.

[Brief explanation of the drawing]

1 and 2 are drawings for explaining different embodiments of the present invention, and FIGS. 5 to 8 are drawings for explaining further different embodiments of the present invention.
These drawings are for explaining the embodiment, and FIG. 9 is a drawing for explaining the conventional example. DESCRIPTION OF SYMBOLS 1...Spiral groove, 2...Central part, 3...Inner circumferential end of the spiral groove, 4...Outer circumferential end of the spiral groove, 5
...Protrusion, 6...Protrusion with outer diameter dimension indicated, 7.
・・・Protrusion showing plate thickness, 8...Protrusion showing rotation direction, 10...Upper intermediate plate, 11...Lower intermediate plate

Claims (1)

[Claims] 1. A disk-shaped hard material with one or more spiral grooves formed between a plane perpendicular to the axis of the rotating member provided at the end of the rotating shaft and a plane of the stationary member opposing this plane. In the intermediate plate of a spiral group bearing with an intermediate plate made of a member interposed therebetween, a plurality of spiral grooves are formed in the plane of the intermediate plate from the outer peripheral edge toward the center, and the central part of this plane is defined as the spiral groove. A circular concave portion having substantially the same depth, and a protrusion forming a symbol specifying the function of the intermediate plate having a height equal to the surface of the convex portion adjacent to the spiral groove is provided in the concave portion. Intermediate plate of spiral group bearings.