JPH09100482A - Production of oil-impregnated sintered bearing - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a process for producing an oil-impregnated sintered bearing requiring a lubricating oil containing minimum kinds and amount of additives if necessary, thereby eliminating the useless consumption of the additive and reducing the cost while achieving the required effect of the additive. SOLUTION: A lubricating oil is impregnated in a sintered bearing 1 produced by sintering metal powder to a prescribed bearing form. A prescribed additive is dropped by a dispenser 4, etc., to the face 1a of the bearing 1 sliding with a shaft to enable the direct addition of the necessary additive to the requiring position. The additive has one or more functions selected from the improvement of abrasion resistance, improvement of oiliness, improvement of extreme-pressure lubricating property, rust-proofing effect and corrosion-proofing effect.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing a sintered oil-impregnated bearing which can be used as a bearing for a small motor, for example.

[0002]

2. Description of the Related Art For example, a sintered oil-impregnated bearing used as a bearing for a small motor is used by impregnating innumerable porous materials with lubricating oil. Various additives are added to the sintered oil-impregnated bearing lubricant as needed. Normally, as the lubricating oil used for sintered oil-impregnated bearings, commercially available lubricating oils that originally contain such additives are used, but the bearing life is improved, initial friction is reduced, and various other bearing performance improvements are made. Therefore, a lubricating oil containing a necessary additive or a dedicated lubricating oil may be used. Usually, in such a case, the type of additive is specified by the lubricating oil manufacturer and requested to be added, or the user adds the additive to the lubricating oil and uses it as the bearing impregnating oil.

[0003]

The commercially available lubricants for sintered oil-impregnated bearings have various versatility in addition to various additives in order to meet all required performances. However, there are types of additives that are unnecessary in terms of required performance, and there is a large amount of waste, which is a waste.
In addition, if a lubricant manufacturer is requested to add an additive, it becomes a custom-made product, which causes a problem that the cost of the lubricant increases.
Furthermore, if the user tries to add an additive to the lubricating oil, equipment for that purpose will be required, and management costs will increase, which also increases the cost.

The present invention has been made in view of such conventional problems, and when the lubricant used in the sintered oil-impregnated bearing further requires an additive, the necessary minimum type and amount. To provide a method for manufacturing a sintered oil-impregnated bearing, which can eliminate the waste of the additive, reduce the cost, and obtain the desired effect of the additive by adding the additive of The purpose is to do.

[0005]

In order to achieve the above object, the invention according to claim 1 impregnates a sintered bearing obtained by sintering metal powder into a desired bearing shape with lubricating oil. After that, a predetermined additive was dropped on the sliding surface with respect to the shaft, and the necessary additive was added directly to the required portion.

According to the invention of claim 2, an additive is added,
It has at least one of the functions of improved wear resistance, improved oiliness, improved extreme pressure, rust prevention, and corrosion protection.

According to the third aspect of the present invention, the additive is one selected from the group consisting of zinc dialkyldithiophosphate, Mo-dialkyldithiocarbite, Mo-dialkyldithiophosphate, and sulfur-adjacent extreme pressure additive. Two or more types are selected.

According to a fourth aspect of the invention, the lubricating oil comprises poly-α.
It contains an olefin copolymer hydride.

According to a fifth aspect of the present invention, when a sintered oil-impregnated bearing body impregnated with a lubricating oil is a single body, or when the sintered oil-impregnated bearing is assembled to a bearing holder, or the shaft is burned. It is dropped when it is inserted into the shaft hole of the oil-impregnated bearing or when the motor having the sintered oil-impregnated bearing is completed.

[0010]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of a method for manufacturing a sintered oil-impregnated bearing according to the present invention will be described below with reference to the drawings. Sintered bearings used for small motors and the like can be obtained by sintering metal powder into a desired bearing shape.When using this as bearings for motors, etc., the sintered bearings should be impregnated with lubricating oil. Use sintered oil-impregnated bearings. Generally, a commercially available sintered bearing is purchased and impregnated with commercially available lubricating oil, or a sintered oil-impregnated bearing impregnated with lubricating oil is purchased. In the present invention, the additive necessary for bearing oil supplementation during the motor assembly process is used by directly dropping it on the sintered oil-impregnated bearing.

The timing of adding the additive to the sintered oil-impregnated bearing is not particularly limited, but may be any of the following timings. As shown in FIG. 1, an additive is added to a unitary sintered oil-impregnated bearing 1 before assembling the bearing assembly, and then the sintered oil-impregnated bearing 1 is press-fitted into the bearing press-fitting portion 3 at the end of the bearing holder 2. A bearing set may be assembled, or an additive may be added to the sintered oil-impregnated bearing 1 after the sintered oil-impregnated bearing 1 is assembled by press-fitting to the bearing press-fitting portion 3 at the end of the bearing holder 2 to assemble the bearing set. Good. In addition, as shown in FIG.
When the shaft 5 is inserted into the central axial hole 1a of the sintered oil-impregnated bearing 1 of the bearing assembly formed by press-fitting the sintered oil-impregnated bearing 1 into the bearing assembly, or after the shaft 5 is incorporated, it is added to the sintered oil-impregnated bearing 1. Agents may be added. Further, an additive may be added to the sintered oil-impregnated bearing 1 when the motor having the sintered oil-impregnated bearing 1 is completed.

When an additive is added to the sintered oil-impregnated bearing 1,
The additive is dropped on the sliding surface with the shaft 5. Therefore, in the state where the shaft is not inserted as in the example shown in FIG. 1, the droplet is directly dropped on the surface of the shaft hole 1a of the sintered oil-impregnated bearing 1 and the shaft is attached to the sintered oil-impregnated bearing 1 as in the example shown in FIG. After 5 is inserted, the additive is dripped from between the inner peripheral edge of the sintered oil-impregnated bearing 1 and the shaft 5 so that the additive permeates the surface of the shaft hole 1 a of the sintered oil-impregnated bearing 1.

The method of dropping the additive is arbitrary, and in addition to the method using the dispenser 4 as shown in FIGS. 1 and 2, a method such as brush coating or spraying may be used.

A more specific example of the method of dropping the additive will be described below. Add an appropriate amount of additive to the sintered oil-impregnated bearing on the sub-table of the bearing holder press-fitting machine, and press-fit the sintered oil-impregnated bearing into the bearing holder with the bearing holder press-fitting machine. The dropping amount of the additive is about 1 μl to 2 μl. Target at least one of the above-mentioned locations for the drip. Further, as shown in FIG. 3, a diametrical V-shaped groove 6 may be formed on the end surface of the sintered oil-impregnated bearing 1, and an additive may be dropped into the groove 6. The additive dropped in the groove 6 permeates the bearing hole 1a from the groove 6 and spreads on the surface of the bearing hole 1a.

As for the additive amount, since the additive is dropped directly on the sliding surface of the bearing shaft, even if the additive amount is smaller than the usual amount, the same or desired effect can be obtained. be able to. For example, when 5 parts by weight is normally required for 100 parts by weight of lubricating oil, according to the present invention,
A sufficient effect can be obtained with an amount less than that.

Examples of the additive include zinc dialkyldithiophosphate, Mo-dialkyldithiocarbide and Mo.
-Dialkyldithiophosphate, and sulfur-adjacent extreme pressure additives such as extreme pressure additives, oil-based materials, and one or more selected from the additive group consisting of commercially available lubricating oil additives, and used It shall be. Then, as the additive, a stock solution may be used depending on the intended purpose, or a commercially available lubricating oil may be used as a diluting solution and diluted to an appropriate concentration, for example, about 10 percent.

By adding an additive to the sintered oil-impregnated bearing, depending on the kind of the additive, any one of the functions of improving wear resistance, improving oiliness, improving extreme pressure, rust prevention, corrosion prevention, etc. It can have more than one function. The oiliness is the adsorptivity to the metal surface, and the extreme pressure property is the property of causing a chemical reaction with the metal surface to adhere to the metal surface to reduce friction.

As the lubricating oil, for example, one containing a hydrogenated poly-α-olefin copolymer or a hydrogenated ethylene-α-olefin copolymer can be used.

According to the embodiment described above, a sintered bearing obtained by sintering metal powder into a desired bearing shape is impregnated with lubricating oil, and then a predetermined addition is made on the sliding surface with the shaft 5. Since the agent is added dropwise, it is possible to intensively supply the additive having a predetermined function to the necessary place, and it is sufficient to add the minimum type and amount of the additive as necessary. It is possible to reduce the cost by eliminating the waste of the agent and to obtain the desired effect of the additive. Further, since it suffices to add the additive to a required place, it is not necessary to add a new facility or process for adding the additive, and the cost can be reduced also from this point.

Further, since the additive can be directly applied to the sliding surface of the sintered oil-impregnated bearing with respect to the shaft, the effect of the additive is strong, and the desired effect can be obtained in a small amount in a short time. .

[0021]

According to the present invention, a sintered bearing obtained by sintering a metal powder into a desired bearing shape is impregnated with lubricating oil, and then a predetermined additive is dropped on the sliding surface with the shaft. Therefore, it is possible to intensively supply the additive having a predetermined function to a necessary place, and it is sufficient to add the minimum kind and the minimum amount of the additive as necessary. The cost can be reduced by omitting the above, and the desired effect of the additive can be obtained. In addition, since it is sufficient to add the additive to a necessary place, it is not necessary to add a new facility or process for adding the additive,
From this point as well, cost reduction can be achieved.

[Brief description of the drawings]

FIG. 1 is a sectional view showing an embodiment of a method for producing a sintered oil-containing product according to the present invention.

FIG. 2 is a perspective view showing another embodiment of the method for producing a sintered oil-containing product according to the present invention.

FIG. 3 is a perspective view showing still another embodiment of the method for producing a sintered oil-containing product according to the present invention.

[Explanation of symbols]

 1 Sintered oil-impregnated bearing 2 Bearing holder 5 Shaft 1a Shaft hole

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Claims (5)

[Claims] 1. A method for manufacturing a sintered oil-impregnated bearing in which a shaft is rotatably supported, wherein a sintered bearing obtained by sintering a metal powder into a desired bearing shape is impregnated with lubricating oil, and then the shaft is obtained. A method for producing a sintered oil-impregnated bearing, characterized in that a predetermined additive is dropped onto the sliding surface of. 2. The additive has a function of at least one of improvement of wear resistance, improvement of oiliness, improvement of extreme pressure property, rust prevention, and corrosion protection. A method for producing a sintered oil-impregnated bearing according to claim 1. 3. The additive is zinc dialkyldithiophosphate,
The one or more selected from the group consisting of Mo-dialkyldithiocarbite, Mo-dialkyldithiophosphate, and sulfur-adjacent extreme pressure additive, calcination according to claim 1. Manufacturing method of oil-impregnated bearing. 4. The method for producing a sintered oil-impregnated bearing according to claim 1, wherein the lubricating oil contains a hydrogenated poly-α-olefin copolymer. 5. The additive is used when the sintered oil-impregnated bearing body impregnated with lubricating oil is a single body, or when the sintered oil-impregnated bearing is assembled to a bearing holder, or the shaft is a shaft hole of the sintered oil-impregnated bearing. The method for producing a sintered oil-impregnated bearing according to claim 1, wherein the droplet is dropped when the motor is equipped with the sintered oil-impregnated bearing or when the motor is completed.