JPS61112818A - fluid bearing - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION [Scope of Application on Tumors] The present invention relates to a fluid bearing, and more particularly to a fluid bearing for improving the lubricity of a bearing contact surface.

[Prior art]

Conventional methods of forming a film on the bearing contact surface using fluororesin or U2M molybdenum include coating the bearing contact surface with fluororesin, but the surface to be coated should have a simple shape, and should not be coated on corners or edges. etc. with a radius of 5 mA
A certain degree of roundness is required, and the film thickness coated with fluororesin or the like varies by several tens of microns, making it impossible to achieve a film thickness with high precision on the order of several microns. Therefore, if precision is required, several grinding sub-processes are required in post-processing. In addition, there are disadvantages such as pinholes and poor adhesion in thin films coated with fluororesin, etc., as well as the process of increasing the surface roughness of the base metal using sand plus etc. to improve the adhesion of the coating.
, it is not optimal as a contact surface for hydrodynamic bearings.

≠ Another method is to anodize the porous nickel plating film and aluminium plating, heat the porous layer on the plating surface, create a crack structure on the plating surface, and use it as an anchor. There is a method of coating the material with 7Sat fat, molybdenum disulfide, etc., and firing it at around 400° C. to form a film of fluororesin, molybdenum disulfide, etc. These merely mechanically prevent thin films such as fluororesin and molybdenum disulfide from detaching from the base metal, and the resin falls off due to poor adhesion to the base metal.
The lifespan of fat is short.

In addition, in the case of impregnation with these resins, the resin layer is only about 5 to 10 microns from the surface, and the machining allowance for rear J machining (for example, grinding) is small, making processing difficult.

[Purpose of the invention]

The present invention eliminates the above-mentioned drawbacks of the conventional example, and at the same time improves the R5 corrosion resistance of the bearing contact surface and the life of the lubricating surface, prevents galling on the bearing contact surface, such as when starting and stopping a hydrodynamic bearing, and is inexpensive. This product provides high-performance hydrodynamic bearings.

〔Example〕

Embodiments of the present invention will be described with reference to the drawings.

The contact surface K between the shaft of the hydrodynamic bearing and the supporting member is coated with BN (boron) composite electroless nickel plating manufactured by Nippon Kanigen.
Apply to a thickness of 0 to 20μ. In this plating, BN must have a moderate particle size of 0.5 to 10 microns, have good dispersibility, and be non-catalytic, non-catalytic, and insoluble, and must be uniformly dispersed in the nickel plating solution. The standard amount of nickel in the plating solution is s, 97t, generally 11-5! ! The amount of powder contained in the electroless nickel plating film is about 20Vot%. Included. The characteristics of this plating are that after heating at 500℃ for 2 hours, the hardness is about 600HV, the friction coefficient is 0.08 at a load of 0.5kg/α2 (7-carbon resin 0.12 to 0.I A ), and the wear resistance is fluorine. It is about the same level as resin or molybdenum sulfide.

FIG. 1 is a diagram in which the aforementioned plating layer 4 is applied to a bearing member 3 on the contact surface of a radial dynamic pressure bearing to a thickness of 10 to 20'μ. In the figure, 1 is the shaft and 2 is the herringbone binding.

FIG. 2 is a diagram in which the aforementioned plating layer 14 is applied to a thickness of 10 to 20 μm on the support member 13 on the contact surface of a single spherical spiral group bearing. In the figure, 11 is a shaft, and 12 is a spherical spiral fermentation.

FIG. 3 is a diagram in which the above-mentioned plating layer 24 is applied in an amount of 10 to 20 .mu.m on the support member 23 on the contact surface of the conical spiral group bearing. In the figure, 21 is a shaft, and 22 is a conical spiral groove.

FIG. 4 is a diagram in which the above-mentioned plating layer 34 is applied to a thickness of 10 to 20 μm on the support member 33 on the contact surface of the planar spiral group bearing. In the figure, 31 is an axis, and 32 is a plane spiral.

〔Effect of the invention〕

As explained above, the following effects can be obtained by applying the above embodiment to the fluid bearing contact surface.

(When nickel plating is applied to 11BNg and nickel, BN and nickel are dispersed and co-deposited to create a plating film, which is different from conventional methods and has good closeness with the entire substrate (BN does not fall off and the lubricating surface has a long life. .

(2) Furthermore, since BN is dispersed and co-deposited, it has excellent frictional properties (Vickers hardness of 600HV to 700HV).

(3) Fluororesin (friction coefficient 0.12, load MO,
51qlZ-2) The friction coefficient is 0.1 (load 0.5
kg/crn2), and there is no galling when starting and stopping the fluid bearing.

(, i) Since the variation in the plating film thickness of BN-free nickel is as small as ±10% of the plating film thickness, I! Post-processing such as grinding after plating is facilitated on the contact surface of the fluid 1 oil receiver, which requires a high degree of hardness.

(5) Also, in the case of impregnation with fluorine, resin, etc., the depth is 5 to 1
0μ, but the thickness of the aforementioned plating layer is 5μ to 50μ and can be applied freely, and since the KBN and nickel are uniformly dispersed and eutectoid within the layer, there is sufficient machining allowance for post-processing (e.g., grinding). Post-processing becomes easier. (Finishing allowance for grinding 10
~5μ)

[Brief explanation of drawings]

FIG. 1 is a sectional view of a main part of one embodiment of a fluid bearing according to the present invention, and FIGS. 2 to 4 are sectional views of main parts of other embodiments. 1.11, 21.31... Shaft 2... Herringbone groove 5.15, 25.55... Bearing member A, 1A, 24, 54 Auto/BIJ electroless nickel plating layer 12... Spherical surface Spiral fermentation 22... Conical spiral groove 32... Planar spiral groove

Claims (1)

[Claims] (1) A fluid bearing comprising a groove for generating fluid pressure in the bearing, characterized in that the bearing contact surface has a BN composite electroless nickel plating layer as a lubricating part.