JP2549642Y2 - Cylinder sleeve of internal combustion engine - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an improvement in a cylinder sleeve of an internal combustion engine in which an inner periphery is plated with wear resistance.

[0002]

2. Description of the Related Art In a cylinder of an internal combustion engine, an inner circumference of a cylinder block of a cylinder block cast with a light alloy or the like is sometimes used after being plated with wear resistance. However, in this case, in the case of a single cylinder, plating can be easily performed even if plating is performed directly on the cylinder block.However, in the case of a multi-cylinder cylinder block, the plating equipment becomes large and expensive, The work efficiency is poor, and the cost is greatly increased.

For this reason, in the case of a multi-cylinder cylinder block, as shown in FIG. 3, a cylinder sleeve B provided with a flange A on the upper end outer periphery is provided with a wear-resistant plating layer C on the inner periphery. The cylinder sleeve B is inserted and fixed in the hole E of the cylinder block D, and the plating is applied to the cylinder sleeve B as a single body so that plating equipment is small and workability is good. When the cylinder sleeve B is inserted and fixed in the cylinder block D, as shown by a two-dot chain line in FIG.
The upper surface of the cylinder sleeve B and the upper surface of the cylinder sleeve B can be irregular. Therefore, a slight allowance is provided, and a cutting process is performed to make the upper surface uniform. On this upper surface, it is necessary to fasten a cylinder head with a gasket therebetween and seal with a gasket, so that surface accuracy for maintaining the sealing performance is required.

However, when the upper surface is cut into a flat surface by cutting, a bite is also applied to the plating layer C, and fine peeling may occur at the upper end of the plating layer C, or surface precision of the processed surface may be poor. If it is formed, it spreads during use, and there is a disadvantage that the durability is remarkably reduced.
Further, the plating layer C is hard and has a problem of shortening the life of the cutting tool. The plating cylinder sleeve or plating cylinder is disclosed in Japanese Utility Model Publication No. Sho 56-1010,
Japanese Patent Application Laid-Open No. 23442/1990 and Japanese Patent Application Laid-Open No. 49-127016 are known.

[0005]

[Problem to be Solved by the Invention] This invention provides a cutting allowance in which a plating layer is not applied to the inner peripheral upper end of the cylinder sleeve.
An object of the present invention is to provide a cylinder sleeve of an internal combustion engine that can provide a cutting portion that eliminates inconvenience in cutting the upper surface and can increase productivity.

[0006]

SUMMARY OF THE INVENTION The present invention relates to a cylinder sleeve of an internal combustion engine in which a cylinder sleeve having a plated layer on an inner peripheral surface is inserted and fixed in a cylinder block.
The cylinder sleeve defines the inner diameter at which the piston operates.
Having an inner diameter and formed at the upper end of the cylinder sleeve
And after inserting it into the cylinder block,
It is a cutting allowance for finishing on the same plane as the block upper surface.
And a cutting portion between the inner diameter portion and the cutting portion.
While forming a curved surface part, the cutting part is parallel to the inner diameter part in cross section.
The object is achieved by a structure of a cylinder sleeve of an internal combustion engine characterized by being formed and being a non-plated region .

[0007]

According to the present invention , the upper surface of the cylinder sleeve is inserted into the cylinder block after the sleeve is inserted into the cylinder block.
It becomes a cutting allowance for finishing on the same surface as the block upper surface
Since a cutting part is provided and the cutting part is a non-plated area,
The peeling of the plating layer during cutting can be prevented.

[0008]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described below with reference to the drawings. As shown in FIGS. 1 and 2, the cylinder sleeve 1 is provided with a flange 2 on the outer periphery of the upper end, and is positioned axially with the hole 4 of the cylinder block 3. The cylinder sleeve 1 is provided with a plating layer 6
An inner diameter part 7 having an inner diameter where the ton operates, and a cylinder.
The cylinder formed at the upper end of the leave 1
After being inserted into the block 3, the upper surface is flush with the upper surface of the block 3.
And a cutting portion 8 serving as a cutting allowance for finishing the surface.
You. The inner diameter of the cutting portion 8 is slightly smaller than that of the inner diameter portion 7.
The enlarged diameter portion 5 is provided. Also, the inner circumference of the cutting part 8
The enlarged diameter portion 5 has an inner peripheral surface having a straight vertical section and an inner diameter portion 7.
Is formed in parallel with the section. The enlarged diameter part 5 on the inner circumference of the cutting part 8
May be about 1 mm in inner diameter and about 1 mm in depth. In addition, the lower end of the enlarged diameter portion 5 forms a curved surface portion 9 that continues between the inner diameter portion 7 of the cylinder sleeve 1 and the cutting portion 8 with a curved surface.
I do.

In the cylinder sleeve 1 thus constructed,
The inner peripheral diameter portion 7, and facilities the wear resistance of the plating layer 6, the cutting
The enlarged diameter portion 5 on the inner periphery of the portion 8 is a non-plated region. For the plating layer 6, hard chrome plating, composite plating containing ceramic particles, or the like is suitable. Since the enlarged diameter portion 5 is recessed radially outward from the inner periphery of the cylinder sleeve 1, the plating layer 6 hardly adheres. The curved portion (curved surface portion 9) at the lower end of the enlarged diameter portion 5 is finished so that the plating layer 6 gradually and thinly adheres toward the enlarged diameter portion 5.

In this way, the cylinder sleeve 1 provided with the plating layer 6 is inserted and fixed in the hole 4 of the cylinder block 3 by cold fitting or shrink fitting. After the insertion, the irregularities of the upper surface of the cylinder block 3 and the upper surface of the cylinder sleeve 1 are cut by cutting to finish them on the same plane. The cutting allowance may be set to about 0.5 mm.

The enlarged diameter portion 5 having a slightly larger inner diameter on the inner periphery of the upper end of the cylinder sleeve 1
When the plating layer 6 is formed on the inner diameter portion 7 of the cylinder sleeve 1 by plating, the plating layer 6 is hard to adhere to the inner peripheral surface of the cylinder sleeve 1 and almost no plating layer 6 is formed. For this reason, the irregularities of the upper surfaces of the cylinder sleeve 1 and the cylinder block 3 are changed by a two-dot chain line in FIGS.
As shown by, when cutting is performed by cutting to finish the same surface , the cut portion 8 which is a cutting allowance is a non-plated region.
Therefore, a bite does not enter the plating layer 6, the surface accuracy of the processed surface can be enhanced, and the plating layer 6 can be prevented from peeling off. It is also possible to use bytes. In this way, the processing accuracy is enhanced, and peeling of the plating layer 6 can be prevented. The enlarged diameter part 5 after cutting has a depth of 0.5
mm, and there is no piston ring, so there is no inconvenience in use. In addition, cylinder sleeve 1
The inner diameter is large, and a plating layer is also formed on the enlarged diameter part 5.
If there is a danger, only the cutting part 8 when plating
It is sufficient to mask it, but the cutting part 8 is
The mask is easy to use because it is formed in parallel and straight.
Also, no plating adheres.

[0012]

As has been described above devised], this invention is a cylinder sleeve plated layer on the inner peripheral surface At a thing to insert secured to the cylinder block, a cylinder Three
Cylinder sleeve after inserting the cylinder into the cylinder block.
Cutting to finish the upper surface flush with the block upper surface
It has a cutting part as a substitute, and the inner diameter part and the cutting part
A curved surface is formed between them, and the cutting part is
Cylinders because they are formed in rows and are non-plated areas
When cutting the irregularities on the upper surface of the leave with the cylinder block to finish it in a flat surface,
As a result, peeling of the plating layer can be prevented, the precision of the processed surface can be improved, and the productivity can be improved. And cutting of cutting tools
Tool life is also increased. Further, since the peeling of the plating layer during use does not spread, the durability of the plating layer is also improved.
In addition, when plating, the cutting part is masked,
Since the shaved part is formed in a straight line parallel to the cross section with the inner diameter part,
The screen is easy and no plating adheres.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view of one embodiment of the present invention.

FIG. 2 is an enlarged vertical sectional view of a main part of FIG.

FIG. 3 is a longitudinal sectional view showing a conventional example.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Cylinder sleeve 3 Cylinder block 5 Large diameter part 6 Plating layer 7 Inner diameter part 8 Folded part 9 Curved surface part

Claims (1)

(57) [Scope of request for utility model registration] 1. A cylinder sleeve of an internal combustion engine in which a cylinder sleeve having a plating layer formed on an inner peripheral surface thereof is inserted and fixed in a cylinder block, wherein the cylinder sleeve has an inner diameter at which a piston operates.
Having an inner diameter and formed at the upper end of the cylinder sleeve
And after inserting it into the cylinder block,
It is a cutting allowance for finishing on the same plane as the block upper surface.
That it has a cutting unit, to form a curved portion between the cutting portion and the inner diameter portion,
The cutting part is formed in parallel with the inner diameter part in cross section and the non-plated area
A cylinder sleeve for an internal combustion engine.