JPS597525Y2 - Valve guide for internal combustion engines - Google Patents

Description

[Detailed Description of the Invention] This invention relates to a valve guide for an internal combustion engine for sliding intake valves and exhaust valves.

As shown in FIG. 1, a valve guide 1 is press-fitted into an aluminum cylinder head 2, and an intake or exhaust valve 5 is slid on the inner peripheral surface of the valve guide 1 to communicate or disconnect an intake or exhaust port 3 and a combustion chamber 4. It's moving.

In addition, 6 is the valve seat for seating the valve 5, and 7 is the valve seat for the valve 5.
8 is a valve stem oil seal, and 9 is a valve spring seat.

By the way, when this valve guide 1 falls off from the cylinder head 2, it collides with the valve 5, causing it to break and pieces to fall into the combustion chamber 4.
In severe cases, the valve may remain open and become unable to close, causing various problems.

Since the valve guide 1 has such problems, in order to prevent it from falling off, a ring 1 is attached to the outer circumferential surface of the valve guide 1 as shown in Fig. 2, or a ring 1 is attached to the outer circumferential surface of the valve guide 1 as shown in Fig. 3. A retaining flange 12 is formed on the outer circumferential surface of 1.

However, even if these measures prevent the valve guide 1 from falling off, the valve 5 becomes a heat point when carbon in the exhaust gas adheres to the exhaust side when the inhalant overlaps or blows back. The oil film of the lubricating oil interposed between the inner circumferential surface of the valve guide 1 and the outer circumferential surface of the stem 10 of the valve 5 is cut, and the stem 10 is exposed to the inner surface of the valve guide 1. , scuffing, wear, and other problems have not been resolved.
It was not possible to provide a high quality valve guide 1.

Therefore, this invention is designed to prevent the valve guide 1 from falling off and to actively dissipate the heat transferred from the valve 5.

The structure of this invention will be explained below based on an embodiment shown in the drawings.

As shown in FIG. 4 and FIG.
3 is carved, and the size of the serrations 13 is changed as necessary.

The press-fit hole 14 of the cylinder head 2 into which the valve guide 1 is press-fitted may be set to a slightly smaller diameter than the outer diameter of the valve guide 1 at normal temperature, taking into account the press-fitting allowance, and if necessary, it may be serrated by broaching. good.

Then, such a valve guide 1 is attached to the cylinder head 2.
In order to attach the valve guide 1 to the valve guide 1, the valve guide 1 may be press-fitted or cold-fitted after being cooled.

This invention is a valve guide for internal combustion engines that is press-fitted into the cylinder head and allows the valve to slide.Since serrations are carved on the outer circumferential surface, the valve guide is firmly fixed to the cylinder head due to the presence of the serrations. It will no longer fall off, and no trouble will occur due to falling off.

In addition, since serrations are carved on the outer circumferential surface of the valve guide, the area for dissipating heat from the valve guide is large, improving heat dissipation efficiency. No more cutting, staking, scuffing, or wear.

Furthermore, the simple structure of carving serrations on the outer peripheral surface of the valve guide has both the functions of preventing falling off and promoting heat dissipation.

[Brief explanation of drawings]

Figure 1 is a vertical sectional view illustrating the outline of the valve guide for internal combustion engines of the present invention, Figures 2 and 3 are longitudinal sectional views showing how a conventional valve guide is attached to a cylinder head, and Figure 4 is a longitudinal sectional view of the valve guide of the present invention. FIG. 5 is a longitudinal cross-sectional view of a valve guide for an internal combustion engine, and FIG. 2... Cylinder head, 5... Valve, 1... Valve guide, 13... Serration.

Claims (1)

[Scope of utility model registration request] 1. A valve guide for an internal combustion engine that is press-fitted into a cylinder head and for sliding a valve, characterized in that serrations are carved on the outer peripheral surface of the valve guide.