JPH10299566A - Cylinder block for internal combustion engine and manufacture of cylinder block - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce costs sufficiently and provide strength by enclosing a cylinder liner formed in such a way that an aluminum material and a plate shaped raw material of an abrasion resistance material are formed in a cylindrical shape so as to expose the aluminum material to an outside and expose the abrasion resistance material to an inside, by a cylinder block of an aluminum casting material. SOLUTION: First flat plate 1 made of aluminum alloy and a second flat plate 2 made of an abrasion resistance material are laminated with each other, and are brought into press contact with each other so as to form a double layered plate raw material 3. The plate raw material 3 is cylindrically bent so as to set the first flat plate 1 to an outside and set the second flat plate 2 to an inside. Those matching surfaces are joined with each other by means of high frequency resistance welding or mechanical joining so as to form a cylindrical cylinder liner 3. The productivity of the cylinder liner 3 formed by bending is improved, and the costs of a cylinder block is sufficiently reduced. Since a part which is brought into contact with the cylinder block main body of the aluminum cast material of the cylinder liner 3 is made of an aluminum material, the cylinder block having sufficient strength is provided.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a cylinder block for an internal combustion engine and a method for manufacturing the cylinder block.

[0002]

2. Description of the Related Art A cylinder block of an internal combustion engine is generally formed by casting. At this time, it is necessary to cast a cylinder liner for forming a cylinder bore into a predetermined position. Such a cylinder liner is usually formed by casting or the like, but is disclosed in Japanese Patent Application No. 7-28975.
No. 9 proposes forming a cylinder liner by bending a plate-like material into a cylindrical shape in order to improve the productivity.

In recent years, it has been strongly desired to reduce the weight of an internal combustion engine in order to reduce the fuel consumption rate, and cylinder blocks made of aluminum casting have been put to practical use.

[0004]

When an aluminum-based material is selected as the plate material in the case of using the above-described plate material cylinder liner according to the prior art for such a cylinder block made of an aluminum casting, wear resistance is reduced. Therefore, a wear-resistant layer must be formed inside the cylindrical cylinder liner. This wear-resistant layer
It is formed by a coating process such as thermal spraying or overlaying. However, this process takes a very long time and lowers the productivity of the cylinder liner, so that a sufficient cost reduction of the cylinder block cannot be realized. In addition, after casting such a cylinder liner, it is necessary to finish the inner peripheral surface of the cylinder bore by honing, etc., but it is difficult to control the conditions for forming a uniform wear-resistant layer, which also increases the cost of the cylinder block. Let it.

[0005] When a wear-resistant material is selected as the plate-shaped material, the adhesion between the aluminum-based casting and the cylinder block body deteriorates due to the difference in linear expansion coefficient between the different materials when the cylinder liner is cast. A strong cylinder block cannot be formed.

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a cylinder block of an internal combustion engine which is formed from an aluminum-based casting, and which can realize a sufficient cost reduction and a sufficient strength, and a method for manufacturing the cylinder block. is there.

[0007]

According to a first aspect of the present invention, there is provided a cylinder block for an internal combustion engine, wherein at least two layers of a plate-like material of an aluminum-based material and a wear-resistant material are exposed to the outside. A cylinder liner formed by bending the cylinder into a cylindrical shape so that the wear-resistant material is exposed to the inside is surrounded by a cylinder block body made of an aluminum-based casting.

According to a second aspect of the present invention, in the method of manufacturing a cylinder block, the aluminum-based material exposes at least two layers of an aluminum-based material and a wear-resistant material to the outside, and the wear-resistant material is exposed. Forming a cylinder liner by bending the cylinder liner into a cylindrical shape so that the cylinder liner is exposed to the inside, and forming a cylinder block by casting the cylinder liner with an aluminum-based molten material to be a cylinder block body. I do.

According to a third aspect of the present invention, there is provided a method of manufacturing a cylinder block according to the second aspect, wherein the plate-shaped material is made of an aluminum-based material and a wear-resistant material. Is characterized by using a plate-shaped material that is pressed against the substrate.

According to a fourth aspect of the present invention, in the method of manufacturing a cylinder block according to the fourth aspect, the aluminum-based material exposes at least two layers of an aluminum-based material and a wear-resistant material to the outside, and the wear-resistant material is exposed. Forming a cylinder liner by bending it into a cylindrical shape such that is exposed inside, forming an intermediate liner having an internal passage closed at both ends, and forming the internal passage between two adjacent cylinder liners. A step of forming a connecting cylinder liner by connecting the plurality of cylinder liners with the intermediate liner interposed so as to cross, and a step of casting the connecting cylinder liner with an aluminum-based molten material that becomes a cylinder block main body; A water pipe that opens both ends of the internal passage of the intermediate liner and extends on both sides of the connecting cylinder liner Step of communicating each other packet by said internal passage, characterized by having a city.

According to a fifth aspect of the present invention, in the cylinder block according to the first aspect, the thickness of the wear-resistant material in the two-layer plate-like material is equal to the thickness of the aluminum-based material. １ ／ or less.

[0012]

FIG. 1 is a perspective view showing a manufacturing process of a cylinder liner used for a cylinder block of an internal combustion engine according to the present invention. This will be described below. First,
First plate 1 of aluminum alloy and thickness t of first plate 1
A second flat plate 2 of a wear-resistant material having a thickness t2 of 1/5 or less with respect to 1 is superimposed, and for example, by applying a pressure of several tons at room temperature, the two are pressed against each other to form a two-layer plate material 3. Form. The material of the first flat plate 1 is the same material or the same material as the cylinder block body made of aluminum casting. on the other hand,
It is preferable that the material of the second flat plate 2 includes a hard material and a lubricant so as to have excellent wear resistance when sliding with the piston and the piston ring. As a hard material, Fe
Alternatively, Cu or the like can be used, and as the lubricant, primary crystal silicon particles, SiC particles, SiC fibers, and glass fibers can be used. Thus, as a material of the second flat plate 2, for example, F
An e-C-Si system or a Cu-Ni-B-Si system can be used.

Next, the plate material 3 formed as described above is bent into a cylindrical shape such that the first flat plate 1 is on the outside and the second flat plate is on the inside. Next, the mating surfaces are joined by high-frequency resistance welding or mechanical joining by a clinch mechanism or the like, thereby forming a cylindrical cylinder liner 3 '. D is the outer diameter of the cylinder liner 3 ', and H is the height of the cylinder liner 3'.

FIG. 2 is a perspective view showing a manufacturing process of the intermediate liner used in the cylinder block of the internal combustion engine according to the present invention. This will be described below. First, for example, a plurality of internal passages 4 a penetrating both side end surfaces are formed in an extruded aluminum alloy plate material 4. The height h of the plate member 4 is smaller than the height H of the cylinder liner, and the width w is larger than the outer diameter D of the cylinder liner. Next, the intermediate liner 4 'is formed by crushing both side end surfaces and closing both ends of the internal passage 4a. The material of the plate material 4 is the same material or the same material as the aluminum-based cast cylinder block body.

FIG. 3 is a perspective view showing the connected cylinder liner. Each cylinder liner 3 'is linearly arranged at a predetermined cylinder bore interval L, and an intermediate liner 4' is interposed between two adjacent cylinder liners 3 'so that the internal passage 4a crosses. At this time, the intermediate liner 4 '
Is the same height as the upper surface of the cylinder liner 3 '. The adjacent cylinder liner 3 ′ and the intermediate liner 4 ′ are joined by welding or the like to form a connection cylinder liner 5. The outer diameter D of the cylinder liner 3 'and the plate thickness t3 of the intermediate liner 4' are selected such that the sum of both (D + t3) matches the predetermined cylinder bore interval L (see FIG. 4).

The connecting cylinder liner 5 is set at a predetermined position in a molding die (not shown), and a molten metal of an aluminum alloy is supplied to cast the connecting cylinder liner 5 into a cylinder block 6 as shown in FIG. Form. When the connecting cylinder liner 5 is installed in the molding die, a projection for a cylinder bore is provided in the molding die in order to prevent the molten metal from entering the inside of each cylinder liner 3 ′. 'May be fitted.

As shown in FIG. 4 and FIG. 5, which is a cross-sectional view taken along the line AA, the molten metal solidifies around the connecting cylinder liner 5 and is cast. Since the outside of the cylinder liner 3 'and the intermediate liner 4' are of the same or the same material as the molten metal,
In such a cast-in case, the adhesion is good, the fixing of the connecting cylinder liner 5 and the connection between each cylinder liner 3 ′ and the intermediate liner 4 ′ are strong, and provide sufficient strength of the cylinder head. can do.

The upper portion of the connecting cylinder liner 5 corresponds to the upper portion of the combustion chamber of each cylinder, and has a very high temperature, so that a water jacket 6a through which cooling water passes is formed therearound. The water jacket 6a can be easily formed by forming the protrusion for the water jacket on the molding die. Since the molten metal penetrates into the gap between the water jacket projection and the crushed side end surface of each intermediate liner 4 ', the periphery of the side end surface is also cast. At this time, both sides of the internal passage 4a are closed as described above so that the molten metal does not enter the internal passage 4a of the intermediate liner 4 '.

Next, as shown in FIG. 6, the cylinder block 6 thus formed is formed with substantially vertical through holes 6b at both ends of each intermediate liner 4 'projecting into the water jacket 6a. The internal passages 4a in each intermediate liner 4 'communicate with each other and open to the upper surface. Cooling water enters into the internal passages 4a of the intermediate liners 4 'thus opened through the cylinder head side water jacket facing the water jacket 6a. In this way, the water jackets extending on both sides of the connecting cylinder liner 5 are communicated by the internal passages 4a of each intermediate liner 4 ', and the cylinder block in this embodiment realizes good cooling for each cylinder. be able to.

Generally, a groove is formed on the upper surface of the cylinder head so that the water jackets extending on both sides of the row of cylinder bores communicate with each other between the cylinder bores. However, when such a groove is formed, if the seal width of each cylinder bore is secured when the cylinder head is mounted, the distance between the cylinder bores becomes longer than necessary. According to the present embodiment, such a problem does not occur.

Since the inside of each cylinder liner 3 'is formed of a wear-resistant material having a predetermined thickness t2, the inner peripheral surface of the cylinder bore is finished by machining or the like. For example, a uniform wear-resistant layer having a desired thickness can be easily formed. As described above, the productivity of the cylinder liner is considerably improved as compared with the case where the wear-resistant layer is formed by coating after forming the cylinder liner from the aluminum alloy plate material.

In the cylinder liner 3 'of this embodiment, the thickness t2 of the inner wear-resistant material is sufficiently smaller than the thickness t1 of the outer aluminum-based material, and further processed by machining or the like. Therefore, the wear-resistant layer in use becomes very thin, and the heat in the combustion chamber can be transferred well to the water jacket in the cylinder block.

In this embodiment, the cylinder liner 3 '
The plate-like material 3 for forming the aluminum alloy has a two-layer structure of an aluminum-based material and an abrasion-resistant material, but this does not limit the present invention, and the abrasion-resistant material and the aluminium-based material are entirely exposed. If so, a structure of three or more layers with other materials interposed may be used. In addition, in forming the plate-shaped material 3,
Although cold pressure welding was used, other methods such as welding can be used.

[0024]

As described above, according to the cylinder block of the internal combustion engine according to the first aspect of the present invention, the aluminum-based material exposes at least two layers of the plate-shaped material of the aluminum-based material and the wear-resistant material to the outside, Since the cylinder liner formed by bending into a cylindrical shape so that the wear-resistant material is exposed to the inside is used, the productivity of the cylinder liner formed only by bending is high, and the cost of the cylinder block can be sufficiently reduced. In addition, since the portion of the cylinder liner that comes into contact with the cylinder block body of the aluminum casting is made of an aluminum-based material, the cylinder liner has good adhesion to the cylinder block body and can provide sufficient strength of the cylinder block.

Further, according to the method for manufacturing a cylinder block according to the second aspect of the present invention, it is possible to manufacture the cylinder block according to the first aspect, which realizes sufficient cost reduction and sufficient strength.

According to a third aspect of the present invention, there is provided a method of manufacturing a cylinder block according to the second aspect, wherein:
Since a plate material in which a plate material of an aluminum-based material and a plate material of a wear-resistant material are pressed against each other is used, the two-layer plate material is manufactured at low cost, and the cost of the cylinder block is further reduced.

According to the method of manufacturing a cylinder block according to a fourth aspect of the present invention, an intermediate liner having an internal passage closed at both ends is formed by using a cylinder liner similar to the first aspect, An aluminum-based connecting cylinder liner is formed by connecting a plurality of cylinder liners with an intermediate liner interposed therebetween so that an internal passage crosses between two adjacent cylinder liners. The cylinder according to claim 2, wherein water jackets extending on both sides of the connecting cylinder liner are communicated with each other by the internal passage of the intermediate liner to open both ends of the internal passage of the intermediate liner after being cast with the molten material. In addition to the same effects as the block manufacturing method, the cylinder bore It is possible to realize a good cooling in each cylinder to ensure Lumpur area.

According to a fifth aspect of the present invention, in the cylinder block according to the first aspect, the thickness of the wear-resistant material in the two-layer plate-like material is one of the thickness of the aluminum-based material. / 5 or less, in addition to the same effect as the cylinder block according to claim 1, the thickness of the wear-resistant material is sufficiently small, and the thickness of the wear-resistant material is further reduced by machining the inner peripheral surface of the cylinder bore. Are uniform and fairly thin so that the heat of the combustion chamber can be transferred well to the water jacket in the cylinder block.

[Brief description of the drawings]

FIG. 1 is a perspective view showing a manufacturing process of a cylinder liner used for a cylinder block of an internal combustion engine according to the present invention.

FIG. 2 is a perspective view showing a manufacturing process of an intermediate liner used for a cylinder block of an internal combustion engine according to the present invention.

FIG. 3 is a perspective view showing a connecting cylinder liner used in a cylinder block according to the present invention.

FIG. 4 is a plan view of the cylinder block immediately after casting a connecting cylinder liner.

FIG. 5 is a sectional view taken along line AA of FIG. 4;

FIG. 6 is an enlarged plan view of a cylinder block in which a through hole has been machined.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... 1st flat plate 2 ... 2nd flat plate 3 ... Plate material 3 '... Cylinder liner 4 ... Plate material 4a ... Internal passage 4' ... Intermediate liner 5 '... Connection cylinder liner 6 ... Cylinder block 6a ... Water jacket 6b ... Through-hole

Claims (5)

[Claims] A cylinder formed by bending at least two layers of an aluminum-based material and a wear-resistant material into a cylindrical shape such that the aluminum-based material is exposed to the outside and the wear-resistant material is exposed to the inside. A cylinder block in which a liner is surrounded by an aluminum-based cylinder block body. 2. A cylinder liner formed by bending at least two layers of an aluminum-based material and a wear-resistant material into a cylindrical shape such that the aluminum-based material is exposed to the outside and the wear-resistant material is exposed to the inside. And forming the cylinder block by casting the cylinder liner with an aluminum-based molten material to be a cylinder block body to form a cylinder block. 3. The method for manufacturing a cylinder block according to claim 2, wherein the plate-shaped material is a plate-shaped material in which an aluminum-based material and a wear-resistant material are pressed against each other. 4. A cylinder liner formed by bending at least two layers of an aluminum-based material and an abrasion-resistant material into a cylindrical shape so that the aluminum-based material is exposed to the outside and the abrasion-resistant material is exposed to the inside. And forming an intermediate liner having an internal passage closed at both ends,
Forming a connecting cylinder liner by connecting the plurality of cylinder liners with the intermediate liner interposed so that the internal passage traverses between two adjacent cylinder liners; and A step of casting with an aluminum-based molten material to be a block main body, and a step of opening both ends of the internal passage of the intermediate liner, and allowing water jackets extending on both sides of the connecting cylinder liner to communicate with each other through the internal passage. A method for manufacturing a cylinder block, comprising: 5. The cylinder block according to claim 1, wherein the thickness of the wear-resistant material in the two-layer plate-shaped material is not more than ５ of the thickness of the aluminum-based material.