JPH0517194B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Application Field) The present invention relates to a bearing material using a ceramic composite material impregnated with metal or synthetic resin.

(Conventional technology and its problems) Originally, suitable materials for bearings are materials that are wear resistant, easily conform to the shaft, have pressure resistance, toughness to withstand impact vibrations, and have a small coefficient of friction. . It is also required to be lightweight and inexpensive, and it is also desirable to have good oil-impregnating properties and oil-holding properties as lubricating properties.

Therefore, the conventionally used copper alloys, tin alloys,
In addition to lead alloys, synthetic resins, etc., oil-impregnated bearings are now being used. Oil-impregnated bearings include those made by sintering copper powder and impregnated with lubricating oil, and those made of copper or Ni and synthetic resin as a base and impregnated with lubricating oil.

However, with the metal powder sintering method, there is a size limit due to the limitations of press molding, and independent pores are likely to occur in the sintered body, which cannot be impregnated with lubricating oil. It had poor oiliness and self-lubricating properties. In addition, alloy-based materials are bulky, and synthetic resin materials lack wear resistance and oil retention properties.

In view of these problems, it is an object of the present invention to provide an oil-impregnated bearing material that is lightweight, has excellent wear resistance, retains lubricating oil well, and is easy to manufacture even in large dimensions.

(Means for Solving the Problems) The oil-impregnated bearing material of the present invention, which was taken to achieve the above object, is characterized by having voids that communicate with each other between the three-dimensional network skeletons; A porous ceramic sintered body having oil reservoir holes formed inside the skeleton along the skeleton is used, and the voids are impregnated with a base material of metal or synthetic resin.

(Example) Hereinafter, the oil-impregnated bearing material of the present invention will be described in detail together with its manufacturing method.

FIG. 1 shows a first embodiment of a ceramic composite oil-impregnated bearing material impregnated with a metal or synthetic resin according to the present invention, and FIG. 2 is a partially enlarged schematic cross-sectional view thereof. Reference numeral 2 denotes a three-dimensional network skeleton formed of ceramics, and a base material 3 of metal or synthetic resin is impregnated between the skeletons 2 and connected to each other. Further, in the center of the skeleton 2, oil reservoir holes 4 are formed that communicate with each other along the direction of the skeleton and reach the inside of the bearing material, and the oil reservoir holes 4 are impregnated with lubricating oil. Before the three-dimensional network skeleton 2 is impregnated with the base material 3, it constitutes a porous ceramic sintered body 5 as shown in FIG. 3.

The porous ceramic sintered body 5 is manufactured using a three-dimensional mesh skeleton (hereinafter, typically referred to as polyurethane foam) formed of a synthetic resin foam material such as foamed polyurethane, and a ceramic slurry.

That is, a polyurethane foam 6 having a mesh-like skeleton as shown in FIG. 31 is formed using a synthetic resin foam material, and then, as shown in FIG. 32, a ceramic slurry 7 is adhered to this and dried and solidified. .
Specifically, polyurethane foam is immersed in a ceramic slurry, then excess slurry is poured out, and the slurry is attached to a synthetic resin skeleton. After drying and solidifying the slurry, when the slurry is fired at a temperature suitable for the composition of the ceramics, the skeleton of the synthetic resin is completely burned out, as shown in Figure 3, and a three-dimensional network of ceramics with oil reservoir holes 4 formed in the center is formed. A shaped skeleton 2 is formed, and voids 8 that communicate with each other are formed between the skeletons 2. In addition, if the polyurethane foam 6 with a thick resin skeleton is used, the oil reservoir hole 4 will also have a large diameter, and a large amount of oil can be retained. In addition, in FIG. 3, the three-dimensional network skeleton of the polyurethane foam 6 is depicted as a membrane for convenience, but in reality, the voids between the skeletons are in communication with each other, and therefore, as shown in FIG. The voids 8 in the porous ceramic sintered body 5 are also in communication with each other.

The ceramic is appropriately selected from wear-resistant materials such as oxides such as Al ₂ O ₃ , nitrides, silicides, borides, and carbides.

Further, the porosity of the porous ceramic sintered body 5 is preferably 50 to 90%. If it exceeds 90%, the strength of the molded product will be insufficient and it will be difficult to handle;
If it is less than %, the strength as a bearing material will be insufficient.

The shape of the porous ceramic sintered body 5 is appropriately formed into a cylindrical shape, a plate shape, etc. depending on the shape of the intended bearing.

Voids 8 in this porous ceramic sintered body 5
The base material 3 to be impregnated with is appropriately selected from cast iron materials containing graphite, copper alloys, tin alloys, lead alloys, plastics, etc., depending on the purpose of the bearing material, such as operating temperature, strength, compatibility with the shaft material, etc. do. For example, if light weight is required as a bearing material, plastic such as epoxy resin is used, and if strength is required, copper alloy is used. In addition, the material of the base material is selected in consideration of economic efficiency.

As a means for impregnating the base material 3 into the porous ceramic sintered compact 5, centrifugal force casting or static casting is used for alloys, and pressurized infiltration or impregnation using centrifugal force is used for plastics. be done.
Incidentally, when impregnating the base material, as shown in FIG. 3, the ends of the oil reservoir holes 4 in the mesh skeleton 2 of the porous ceramic sintered body 5 are closed by the sintered ceramic. , the base material 3 does not enter the oil sump hole 4 and is impregnated only into the void 8. After the base material 3 is impregnated, the surface layer of the composite material is removed along line A-A, so that the end of the oil reservoir hole 4 communicates with the outside, and only the oil reservoir hole 4 can be impregnated with lubricating oil.

In the bearing material of the present invention, the base material 3 of metal or plastic is impregnated between the three-dimensional mesh skeleton 2 of ceramics, so that the ceramic has various properties required for the bearing material without impairing wear resistance. can be easily applied through the substrate. In particular, when a relatively soft material is used as the base material, as shown in Figure 4, part of the base material part wears out on the shaft sliding surface, creating a dent 9, which acts as an oil reservoir and spreads over the entire surface. Good bearing characteristics can be obtained. Also,
Oil reservoir holes 4 are formed in the center of the framework 2 and communicate with each other to the inside of the bearing material, so it has excellent oil retention ability and allows oil to penetrate into the inside very easily. It will be done. For this reason,
The base material does not need to be self-lubricating, and any material can be selected from a wide range of materials depending on where the bearing material is used.

Although Fig. 1 shows a cylindrical bearing material that is relatively long in the axial direction, it may be cut in the axial direction to make a shorter bearing material, or it can be divided in the radial direction to have a semicircular cross section. It can also be used as Furthermore, it is natural that the surface of the bearing material on the side on which the shaft slides is smoothed by polishing or the like.

FIG. 5 shows a second embodiment of the present invention, which has a two-layer structure in which an outer layer 10 made of only a base material is integrally formed up to the outer peripheral surface of a ceramic composite oil-impregnated bearing part 11 impregnated with metal or synthetic resin. It is a bearing material and is suitable when the outer surface requires machining or when strength is required. Since ceramics have poor workability due to their high hardness, such a structure is advantageous. The two-layer structure is not limited to this embodiment, and it goes without saying that a layer consisting only of the base material may be formed on the inner peripheral surface of the ceramic composite oil-impregnated bearing part 11 impregnated with metal or synthetic resin. Can be used appropriately depending on the purpose.

Next, specific examples will be listed and explained.

Example 1 (1) Polyurethane foam with an outer diameter of 125 mm, an inner diameter of 115 mm, and a length of 150 mm, 50% Al ₂ O ₃ and cordierite.
1100 after uniformly applying 50% slurry and drying
C. to obtain a cylindrical porous ceramic sintered body having a three-dimensional ceramic network skeleton.

(2) The voids of this ceramic molded body are impregnated with molten copper alloy having the following composition (wt%), and then the surface layer of the composite material is removed and the end of the oil sump hole formed by burning out the polyurethane skeleton is communicated with the outside air. After that, the oil reservoir hole in the ceramic skeleton was impregnated with machine oil to obtain a composite bearing material.

Sn: 19.16% Fe: 0.13% Zn: 0.43% The remainder is essentially Cu (3) The oil-impregnated bearing of this example was lighter than a conventional copper alloy bearing of the same volume and had superior wear resistance. .

Example 2 (1) Using the same method as Example 1, the outer diameter was 250 mm and the inner diameter was
A porous ceramic sintered body made of alumina with a length of 230 mm and a length of 350 mm was manufactured, and epoxy resin was centrifugally cast into the void, and an outer layer made only of epoxy resin was integrally formed on the outer surface of the molded body. Thereafter, in the same manner as in Example 1, machine oil was infiltrated into the oil reservoir hole in the ceramic skeleton to obtain a composite bearing material.

(2) This composite oil-impregnated bearing material was easily compatible with the shaft, had good oil-retaining properties, was lightweight, and had excellent wear resistance, compared to conventional materials made only of resin or ceramics.

(Effects of the Invention) As explained above, the oil-impregnated bearing material of the present invention has a metal or plastic base material impregnated between the three-dimensional mesh structure of ceramics, which has excellent wear resistance. In addition to wear resistance, various properties required as a bearing material can be easily imparted. In addition, oil sump holes that communicate with each other are formed inside the framework, and since these communicate with the inside of the bearing material, there is almost no unimpregnated portion of the base material, resulting in excellent quality. As an impregnated bearing, it has excellent oil retention ability and can be impregnated with lubricating oil extremely easily. Therefore, the base material impregnated into the void does not need to have self-lubricating properties, and any material can be selected from a wide range of materials depending on the location where the bearing material is used. Furthermore,
The oil-impregnated bearing material of the present invention uses a ceramic sintered body composed of the above-mentioned skeleton, and the voids are impregnated with a base material, so there is no size restriction like that of sintered materials, and it can be used in large sizes. It can also be easily manufactured.

[Brief explanation of drawings]

Fig. 1 is a sectional view of a ceramic composite oil-impregnated bearing material impregnated with metal or synthetic resin according to an embodiment of the present invention, Fig. 2 is a schematic enlarged partial cross-sectional view of the same bearing material, and Fig. 3 1 to 4 are porous bearing materials. FIG. 2 is an enlarged partial cross-sectional schematic diagram showing the manufacturing process of a ceramic sintered compact;
1 shows the polyurethane foam, FIG. 2 shows the state of adhesion of ceramic slurry, and FIG.
Figure 4 shows a porous ceramic sintered body.
4 shows the same molded product after impregnating the base material, FIG. 4 is an enlarged partial cross-sectional schematic diagram showing the usage status of the composite oil-impregnated bearing material of the present invention, and FIG. 5 shows a composite oil-impregnated bearing according to another example. A cross-sectional view of the material is shown. 2... Three-dimensional mesh skeleton, 3... Base material, 4...
Oil sump hole, 5... Porous ceramic sintered body.

Claims (1)

[Claims] 1 Using a porous sintered ceramic molded body having voids that communicate with each other between the three-dimensional network skeletons and having oil reservoir holes formed inside the framework along the framework, the voids are filled with metal or A composite oil-impregnated bearing material characterized by being impregnated with a synthetic resin base material.