JPH04222897A - Slide bearing - Google Patents

Abstract

PURPOSE:To provide a slide bearing having improved abrasion resistance and capable of properly releasing electrostatic charge. CONSTITUTION:A carbon fiber 5 produced by the vapor-phase thermal decomposition of a hydrocarbon and grown by using ultrafine powder of a high-melting metal and/or its compound as a growth starting point is applied to a bearing made of a plastic to obtain the objective slide bearing 1.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sliding bearing used as a bearing for a rotating shaft of office equipment such as a printer or a facsimile machine.

0002

2. Description of the Related Art Hitherto, various types of printers and facsimile machines have been used as office equipment, for example, for carrying out operations such as conveying paper. The movable parts of this type of office equipment use small metal rotating shafts that perform rotational movements.
For example, a small sliding bearing is used as a bearing for this rotating shaft. As the material for the slide bearing, a synthetic resin material is used because it is desirable to have a small coefficient of friction, excellent wear resistance, and be lightweight.

0003

[Problem to be Solved by the Invention] However, in recent years, there has been a demand for high-speed printing using, for example, various printers, so the problem that conventional sliding bearings do not necessarily have sufficient durability such as wear resistance has arisen. there were.

[0004] Furthermore, in office equipment and the like that use resin sliding bearings, static electricity generated inside the equipment tends to accumulate, so there is a problem in that a large amount of static electricity suddenly flows and makes it difficult to use the equipment comfortably. . Furthermore, in some cases, static electricity can corrupt information stored or transmitted as electrical signals.

SUMMARY OF THE INVENTION An object of the present invention is to solve the above problems and provide a sliding bearing that is highly durable and capable of dissipating static electricity.

[0006]

[Means for Solving the Problems] That is, the present invention, which has been made to achieve the above object, is a sliding bearing equipped with a resin bearing portion that contacts a rotating shaft, which uses a gas phase method using thermal decomposition of hydrocarbons. The gist of the present invention is a sliding bearing characterized in that carbon fibers produced and grown using ultrafine powder of a high melting point metal and/or a compound of the metal as a growth starting part are added to the bearing part.

[0007] The resin bearing may be made of various materials with excellent wear resistance. For example, nylon, ABS resin, etc. Furthermore, unlike polyacrylonitrile-based carbon fibers or pitch-based carbon fibers, the carbon fibers are produced in the form of whiskers with a minute diameter approximately equal to the diameter of ultrafine powder of a high melting point metal and/or its compound.

Furthermore, the high melting point metal used in the present invention is a metal that does not vaporize at 950 to 1300° C., which is the temperature for thermal decomposition of carbon hydrogen, and is a metal that does not vaporize at 950 to 1300° C., which is the temperature for thermal decomposition of carbon hydrogen, and is a metal that does not vaporize at 950 to 1300° C. Group 5a such as Nb, Group 6a such as Cr and Mo
Group 7a elements, such as Mn, and Group 8 elements, such as Fe and Co, are suitable, and particularly desirable are Fe, Co, Ni, V, and Nb.
, Ta, Ti, and Zr. Compounds of such metals include their oxides, nitrides, and other salts.

[0009] Furthermore, the surface of the carbon fibers may be plated with tin or the like, and in this case it is preferable because the dispersibility of the carbon fibers is excellent.

0010

[Operation] The sliding bearing of the present invention has the above-mentioned carbon fiber added to a resin bearing portion. Since the carbon fiber has regular graphite crystal layers formed therein, it has excellent mechanical properties such as tensile strength, which is a characteristic unique to carbon fiber. Furthermore, since these fine carbon fibers have a good affinity for resin, the carbon fibers are dispersed and present in the resin bearing, significantly improving mechanical strength and preventing the occurrence of cracks. Furthermore, since the carbon fibers have excellent wear resistance, they are highly durable, and particularly in areas where the carbon fibers are exposed on the surface, the lubrication performance is improved. Furthermore, since the carbon fibers have appropriate conductivity, they can dissipate generated static electricity and prevent it from accumulating.

[0011]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 shows a sliding bearing 1 to which the present invention is applied.

As shown in FIG. 1, the slide bearing 1 is a cylindrical bearing with a thin wall, and a metal rotating shaft 3 is rotatably inserted into the through hole 2 of the slide bearing 1. There is. This sliding bearing 1 is made of a hard synthetic resin such as nylon, and this synthetic resin contains dispersed fine carbon fibers 5 as described below. Therefore, the carbon fibers 5 are exposed on the inner peripheral surface 6 of the through hole 2 of the slide bearing 1.

Further, as shown in FIG. 2, the slide bearing 1 is attached, for example, to a support wall 9 of office equipment via a housing 8, or directly to the support wall 9.

Next, a method of manufacturing this slide bearing 1 will be explained. First, benzene is thermally decomposed in a furnace at 950 to 1300°C using a gas phase method, with a particle size of 0.02 to 0.
Using iron powder with a diameter of 0.3 μm as a growth initiator,
．． The fine carbon fibers 5 used in this example are manufactured by growing carbon fibers of 5 μm and 0.1 to 1 mm in length.

On the other hand, a method for manufacturing the synthetic resin (for example, nylon, ABS resin, etc.) into which the carbon fibers 5 are mixed is as follows, for example. That is, synthetic resin pellets and carbon fibers 5 are dry-blended using a Henshall mixer, a super mixer, etc., and then the powder formed by the dry blending is processed using a single-screw or twin-screw extruder. The mixture is kneaded, then extruded as a strand with a round or square cross section, and then cut into appropriate lengths using a cutting machine.

Then, using the synthetic resin material produced by the method described above, that is, the synthetic resin material containing carbon fibers 5, it is formed into a predetermined shape of the sliding bearing 1 by well-known injection molding or the like. .

The slide bearing 1 formed in this way is
It has a structure in which carbon fibers 5 are contained inside and the carbon fibers 5 are exposed on the inner circumferential surface 6. Therefore, when the rotating shaft 3 is inserted into the through hole 2 of the sliding bearing 1 and used, the rotating shaft 3
Even when used while rotating at high speed, it has the advantage of being easy to rotate and hard to wear. In addition, this carbon fiber 5 has appropriate conductivity and can appropriately dissipate static electricity generated inside the device, so it can reduce discomfort caused by static electricity when using the device, and moreover, it can malfunction electronic devices due to static electricity. It has the effect of preventing

Although the embodiments of the present invention have been described above,
It goes without saying that the present invention is not limited to these embodiments in any way, and may be implemented in various forms without departing from the gist of the present invention.

For example, in order to expose a large amount of the carbon fibers 5 on the inner circumferential surface 6 of the through hole 2 of the plain bearing 1, centrifugal force is used to manufacture the bearing alloy part of the well-known metal plain bearing. It may be manufactured by

This method of utilizing centrifugal force involves, for example, rotating a cylindrical member corresponding to a backing metal, and injecting a molten synthetic resin containing carbon fibers 5 into the through hole from the center of the through hole of the cylindrical member. It is poured onto the inner circumferential surface of the tube and is applied so as to uniformly cover the surface of the inner circumferential surface.

In order to improve the property of dissipating static electricity, the surface of the carbon fiber 5 may be plated with Cu, Ag, etc. by electroplating, electroless plating, or the like.

[0022]

[Effects of the Invention] As detailed above, the sliding bearing of the present invention has improved lubrication performance and wear resistance because the carbon fiber produced as described above is added to the resin bearing part. Excellent, and also has great mechanical strength. In addition, carbon fiber has appropriate conductivity, so it can appropriately dissipate static electricity generated inside devices, reducing the discomfort caused by static electricity in devices, and preventing malfunctions of electronic devices. can.

[Brief explanation of the drawing]

FIG. 1 is a partially cutaway perspective view showing how a sliding bearing according to an embodiment of the present invention is used.

FIG. 2 is a sectional view showing a sliding bearing attached to a support wall.

[Explanation of symbols]

Claims (1)

[Claims] Claim 1: A sliding bearing equipped with a resin bearing part that comes into contact with a rotating shaft, which is produced by a gas phase method using thermal decomposition of hydrocarbons, and is made of ultrafine powder of a high melting point metal and/or a compound of the metal. 1. A sliding bearing characterized in that carbon fiber grown using a growth starting portion is added to the bearing portion.