JPS593178Y2 - internal combustion engine cylinder - Google Patents

Description

[Detailed Description of the Invention] This invention relates to a cylinder component for an internal combustion engine in which the sleeve is cast in a light alloy barrel.

Small internal combustion engines use cylinders in which a sleeve made of cast iron or the like is enclosed in a light alloy barrel.

In that case, a circumferential protrusion may be provided on the outer periphery of the sleeve, or
As shown in FIG. 1, grid-like ribs B are provided on the outer periphery of the sleeve A in the vertical and horizontal directions in the circumferential and axial directions, and the sleeve A is cast into the barrel C made of light alloy when it is cast.

In this way, the sleeve A and the barrel C can be firmly fixed together by the rib B so that they do not move.

However, since the combustion chamber of an internal combustion engine is located at the upper end of sleeve A, when explosion pressure is applied, as shown in Figure 2,
Areas with horizontal ribs B have sufficient strength and can withstand pressure, while areas with only vertical ribs B have little withstand pressure.
weak.

For this reason, the inner diameter type also changes significantly, contact with the piston becomes uneven, piston seizure and piston ring gaps are likely to occur, and combustion gas sealing performance deteriorates, causing the output to drop by 4 degrees. Become.

This invention has been improved in view of these points, and an embodiment of the invention shown in FIGS. 3 and 4 will be described below.

Diagonal lattice-like ribs 2 are formed on the entire outer periphery of a sleeve 1 made of cast iron or the like.

When the sleeve 1 and the barrel 3 are cast from light alloy,
Shroud.

When casting the sleeve 1, the diagonal lattice-shaped ribs 2 can be easily formed by dividing the outer mold into three parts, and can also be formed by orienting the ribs 2 in the drawing direction even when the outer mold is divided into two parts.

The effect will be explained.

The inner upper end of the sleeve 1 becomes a combustion chamber and is subjected to combustion pressure.Since the sleeve 1 is provided with diagonal lattice-like ribs 2, the strength can be made uniform and the internal pressure can be adjusted according to the internal pressure as shown in Fig. 4. The internal pressure changes in a curve like this.

Therefore, the inner diameter type also has little variation, and the contact with the piston and piston ring is uniform, reducing the leakage of combustion gas.
It has low output loss and can be made into a high output engine.

As explained above, in this invention, diagonal lattice-like ribs are provided on the entire outer circumference of the sleeve, and the sleeve is cast in a light alloy barrel, so that the sleeve and barrel can be firmly fixed by the ribs, and Since the ribs are formed in a diagonal grid pattern, the strength of the sleeve can be made uniform.

For this reason, even when subjected to explosive pressure, the strain on the inner diameter can be made uniform.
Smooth contact with the piston and piston ring results in less leakage of explosive gas, less power loss, and higher output.

[Brief explanation of drawings]

Fig. 1 is a longitudinal sectional view with a part cut away showing a conventional example, Fig. 2 is a line diagram showing changes in the sleeve when subjected to internal pressure in the conventional example, etc. Fig. 3 shows an embodiment of the present invention. FIG. 4 is a longitudinal sectional view with a portion cut away, and is a diagram showing changes in the sleeve of the present invention due to internal pressure. 1... Sleeve, 2... Rib, 3... Barrel.

Claims (1)

[Scope of utility model registration request] A cylinder for an internal combustion engine, characterized in that a diagonal lattice-like rib is provided on the entire outer circumference of the sleeve, and the sleeve is cast in a light alloy barrel.