JPS60165306A - Preparation of cam shaft - Google Patents

Abstract

PURPOSE:To obtain a cam shaft wherein assembling parts and a stem are strongly bonded, by a method wherein the assembling parts having an engagement hole comprising a copper-carbon-ferrous solid phase sintered material containing a specific amount of Cu is engaged and assembled with the stem and the obtained assembly is sintered in a furnace. CONSTITUTION:Assembling parts 1 having an engagement hole comprising a copper-carbon-ferrous solid phase sintered material containing 17-35wt% of Cu and 0.6-1.5wt% of carbon is engaged and assembled with a stem 2 and the resulting assembly is subsequently sintered at about 1,100-1,200 deg.C for about 30- 150min in a furnace. By this method, Cu in the solid phase sintered material is melted and exuded, and penetrated into the gap of the assembling parts 1 and the stem to cement and bond both of them. In this case, the void ratio of the sintered 10-40%. As a result, a cam shaft having excellent processability is prepared simply.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for manufacturing a cam shirt 1-, and in detail, a cam shirt 1-. A, 7-st tv* (7) Assembling parts i, using a solid phase sintered material containing a predetermined amount of copper and having a fitting hole, the assembling parts are made of hollow or solid steel. After fitting into the specified position of the stem made of aluminum, it is sintered in a furnace, and the copper eluted from the assembled parts solidifies and solidifies the assembled parts and the stem, making it simple and easy to work. This invention relates to a method for manufacturing a camshaft.

Various camshafts have been proposed by assembling parts such as cam lobes and journals into a stem, especially a hollow pipe, and are lighter and lighter than conventional integral camshafts made by casting. The number of high-performance products is increasing.

Casting,
There are welding, brazing, etc., but these methods have their own problems such as the need for special techniques, the occurrence of deformation, distortion, and insufficient adhesion, and they also require a lot of man-hours such as operating the welding machine and placing the brazing metal. It cannot be said that it is an easy method.

Another method is to assemble parts made of liquid-phase sintered material to the stem of a hollow steel pipe, etc., and then use the shrinkage of the liquid-phase sintered material to fix it to the stem of the hollow pipe, etc. -C has excellent wear resistance. However, since this camshaft has high hardness and high wear resistance, there is a processing problem in that it is difficult to grind the sliding surface to finish the dimensions.

The present invention provides a method for manufacturing a camshaft r) which allows easy attachment of assembly parts such as journals and cam lobes to the stem, has excellent adhesive strength between the stem and the assembly parts, and has excellent workability. The purpose is to provide.

As a result of intensive research in line with this objective, the present inventors used solid-phase sintered material as assembly parts for journals, etc., and by incorporating a specific amount of copper into this solid-phase sintered material, After the assembled parts are fitted to the stem, when they are sintered in a furnace, the copper in the in-phase sintered material melts and leaches out, enters the gap between the assembled parts and the stem, and solidifies and bonds the two. I found out that
The present invention was achieved by discovering that this method satisfies the above objectives.

That is, the present invention is made of a copper-carbon-iron solid phase sintered material containing 17 to 35% by weight of Cu, and after fitting and assembling an assembly part having a fitting hole to a stem, it is placed in a furnace. A method of manufacturing a cam shirt L- is characterized by sintering the cam shirt.

In the present invention, C uses a copper-carbon-iron solid phase sintered material containing 17 to 35% by weight of copper as an assembly part. In addition,
Copper is contained in the solid phase sintering agent in the form of pure copper or copper alloy, but in any case, the copper content must be within the above range, and the copper content in the solid phase sintering agent must be within the above range. If the amount is less than 17% by weight, the bonding between the assembly parts and the stem will be insufficient, and if it exceeds 35% by weight, it will not contribute much to the bonding between the assembly components and the stem, and the cost will increase, which is economically disadvantageous. It is. In addition, the in-phase sintered material used in the present invention contains carbon as an essential component, and the preferable content is 0.6 to 0.
It is 1.5% by weight. If the carbon content is less than 0.6% by weight, the amount of carbides decreases, resulting in a decrease in wear resistance,
If the content exceeds % by weight, carbides will be excessive, impairing workability. In addition, elements such as Mn, St, Ni, MO, etc. are appropriately contained as optional components in this solid phase sintered material, and properties such as strength and wear resistance can be adjusted, and the content thereof is usually 0. It is in the range of .2 to 4.0% by weight. Further, it goes without saying that this sintered material contains a trace amount of accompanying impurities. In the present invention, it is necessary to appropriately determine the porosity of the sintered material because copper diffuses and moves by sintering the solid-phase sintered material after fitting it into the stem. The ratio is preferably in the range of 10-40%.

In addition, this solid phase sintered material is used as assembly parts,
Examples of parts include a cam lobe and a journal, and the present invention is particularly suitable for attaching a journal to a stem. This assembly part has a fitting hole to fit into the stem. It is important that the inner diameter of the hole is approximately the same as the outer diameter of the stem, and that it is dimensioned to fit closely against the stem.

In the present invention, the assembly part is fitted into a desired portion of a stem made of steel or the like. The stem may be either hollow or solid. A preferable stem is, for example, C defined in JIS STKM13: '0.1
7% by weight, 3i: 0.14 Mm%, Mn: 0
, 54% by weight, P: 0,013% by weight, S2 0.004
A steel pipe consisting of % by weight and balance iron is exemplified.

In the present invention, after the assembled parts are fitted into desired portions of the stem in this way, they are sintered in a furnace. The sintering conditions must be appropriately selected so that the copper in the solid phase sintered material is sufficiently melted and leached out.
Perform sintering for 50 minutes.

By sintering in this manner, copper melts and leaches from the in-phase sintered material, enters the gap between the assembled parts and the stem, and solidifies and bonds to tightly bond the two.

Hereinafter, the present invention will be explained in detail based on the drawings.

FIG. 1 is a longitudinal sectional front view showing one embodiment of a camshield 1- obtained according to the present invention, and FIG. 2 is a longitudinal sectional side view taken along the line AA' in FIG. 1.

A journal 1 having a fitting hole made of a copper-carbon-iron solid phase sintered material consisting of a heavy stitch of Ca2O, 1.0% by weight of C, and the balance Fe is fitted and assembled into a predetermined position of a hollow steel stem 2. After that, it was sintered in a furnace. The copper melted and leached from the journal 1 entered the gap between the journal 1 and the stem 2, the gap was filled with copper without any problem, and the journal 1 and the stem 2 were joined by solidifying the copper.

The present invention as described above has the following effects.

■2) Unlike liquid-phase sintered materials, which generally have high hardness due to the formation of phosphorus-containing eutectic (Sutetai!), the use of low-hardness in-phase sintered materials has good workability (cutting ability). became. Since the solid phase sintered material contains carbon, a certain degree of wear resistance is guaranteed due to diffusion bonding between particles, formation of carbides, etc.

■: It is a simple method that does not require the operation of a welding machine or the placement of brazing metal.

■: Copper is dissolved in solid phase sintered v5+, i to approximately 2% ■,
Contributes to improvements in strength, wear resistance, etc.

[Brief explanation of the drawing]

FIG. 1 is a longitudinal sectional front view showing one embodiment of the camshaft 1171 obtained by the present invention, and FIG. 2 is a vertical sectional view taken along line A-A' in FIG. 11 views. 1... Journal (assembly parts), 2... Stem. Patent applicant Nippon Piston Ring Co., Ltd. Agent Ben
Attorney Tatsuo Ito, Physician, Tetsuya Ito, Patent Attorney (Article 1 Proceedings, amendments, voluntarily written) April 12, 1980 Commissioner of the Japan Patent Office Kazuo Wakasugi 1, Indication of the case 1988 Patent application No. 19400M2, name of invention Method for manufacturing camshaft 3, relationship with the case of the person making the amendment Patent application residence 4-2-6 Kudankita, Chiyoda-ku, Tokyo Name
Nippon Pist Schilling Co., Ltd. Representative Yasuhisa Ishida 4, Agent 105 Address 2-8-1-5 Toranomon, Minato-ku, Tokyo In the specification subject to amendment, [Detailed description of the invention column] 6. Amendment Content 1: ``Because carbides are reduced'' in the first line of page 5 of the specification.
Corrected to ``Because the amount of ferrite increases.''

Claims (1)

[Claims] 1. An assembly part made of a copper-carbon-iron solid phase sintered material containing 17 to 35% Cu by weight and having a fitting hole is fitted to the stem (=J 1. A method for manufacturing a cam shirt, characterized in that the stem is sintered in a furnace. 2. A method for manufacturing a patented shaft, characterized in that the assembly part is a V-nal. 3. The stem is sintered in a furnace. A method for manufacturing a camshaft according to claim 1 or 2, wherein the camshaft is made of steel.