JPH075239Y2 - Engine cylinder block - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial field of application) The present invention relates to improvement of a cylinder block of an engine.

(Prior Art) Conventionally, when a cylinder block, which is an engine component of a vehicle such as an automobile, is made of a light metal such as an Al alloy, a plurality of cast irons are disclosed, for example, as disclosed in JP-A-62-77149. It is common practice to ensure the sliding resistance of the cylinder bores by making the cylinder liners made of steel and adjoining each other and surrounding them. As a cylinder block formed by casting a cylinder liner in this manner, for example, as disclosed in Japanese Patent Laid-Open No. 61-155645, a plurality of annular projections formed on adjacent cylinder liners are confused with each other. It is known that the distance between the cylinder bores is narrowed by this, and thereby the length in the cylinder runner arrangement direction is shortened.

(Problems to be solved by the invention) However, when the space between the adjacent cylinder bores is narrowed in this way, when casting a cylinder block in which a cylinder liner is cast as described above, it is injected into the cavity of the mold. It tends to be difficult for molten metal melt to travel between adjacent cylinder liners. In particular, a cylinder liner of a type provided with a flange for forming a sealing surface with the gasket on the upper surface in order to secure sealing properties such as sealing area and sealing strength of the gasket interposed between the cylinder block and the cylinder head. In the case of using, the gap between the flanges of the adjacent cylinder liners becomes narrower than that at other places, and the hot water flow between the flanges becomes worse.
Then, when the hot water flow between the flanges of the adjacent cylinder liners becomes poor in this way, casting defects such as a molten metal boundary and blowholes easily occur, and the frequency of cracks caused by these casting defects is increased. There was the problem of becoming expensive.

On the other hand, for example, as disclosed in Japanese Patent Publication No. 56-23693, an annular protrusion is provided on the outer peripheral surface of the cylinder liner, and a plurality of grooves are formed in the annular protrusion, so that the gas generated during casting is It has been proposed to smoothly escape upward through each groove to prevent casting defects such as "blurring". Then, it is possible to apply this idea to the cylinder liner with a flange as described above. However, in this case, although the molten metal whirl in portions other than between the flanges of the adjacent cylinder liners is improved by forming the groove, the molten metal whirl performance between the flanges is still unsolved.

The present invention has been made in view of the above point, and an object of the present invention is to form a plurality of flanged cylinder liners adjacent to each other as described above and to circulate them. In this case, among the cylinder liners, By taking appropriate measures on the outer periphery of the adjacent portion of each flange of the adjacent cylinder liners, while ensuring the sealing property of the gasket interposed between the cylinder block and the cylinder head,
It is intended to improve the melt-flow property between the flanges of adjacent cylinder liners of the molten metal during casting.

(Means for Solving the Problem) In order to achieve the above-mentioned object, the solution means of the present invention is a plurality of cylinder liners having a flange for forming a sealing surface with a gasket on the upper surface to form a cylinder bore of an engine. Targeting light metal cylinder blocks that are cast adjacent to each other and in this case, in this case, a notch shape extending in the cylinder bore center line direction is formed on the outer periphery of the adjacent portion of each flange of the adjacent cylinder liners of the above cylinder liners. A plurality of grooves are formed in the circumferential direction.

(Operation) According to the present invention, according to the present invention, among the plurality of cylinder liners provided with the flanges that form the cylinder bores of the engine and are adjacent to each other and are surrounded by casting and that form a sealing surface with the gasket, Since a plurality of notched grooves extending in the cylinder bore center line direction are formed in the circumferential direction on the outer periphery of the adjacent portions of the respective flanges of the adjacent cylinder liners, they are adjacent to each other by the groove shape of the respective grooves. The spacing between the flanges of the cylinder liner is wide. As a result, the molten metal injected into the cavity of the mold is swiftly caused to flow into the respective grooves of the adjacent cylinder liners, and the deterioration of the molten metal is eliminated. The occurrence of casting defects such as blowholes is reduced, and the frequency of cracks is reduced. Further, each of the above-mentioned grooves is not formed over the entire circumference of the flange but is formed partially, and the flange projecting dimension between the grooves adjacent to each other at the groove forming location is the same as that of the other location. Therefore, the sealing property of the gasket interposed between the cylinder block and the cylinder head is ensured.

Embodiment An embodiment of the present invention will be described below with reference to the drawings.

FIG. 3 shows a cylinder block 1 according to an embodiment of the present invention of an engine for vehicles such as automobiles.
Includes a cylinder block body 2 made of a light metal such as an Al alloy. A plurality of (only three in FIG. 3) cast iron cylinder liners 3, 3, ... Are made adjacent to each other in the cylinder block body 2 and are cast around, and the cylinder liners 3 cause cylinder bores of the engine. 4 is formed.

In addition, one end of each cylinder liner 3 (upper end in FIG. 3)
On the upper surface, there is integrally formed a flange 5 extending outward in the radial direction of the cylinder bore which forms a sealing surface with a gasket 6 (shown in FIG. 1) interposed between the cylinder block 1 and a cylinder head (not shown). The flange 5 ensures the sealing property such as the sealing area and the sealing strength of the gasket 6.

Further, as a feature of the present invention, each of the above cylinder liners 3
Of the adjacent cylinder liners 3, 3 on the outer periphery of the adjacent portions of the respective flanges 5, 5, a triangular cutout extending in the direction of the cylinder bore center line is shown in enlarged detail in FIGS. 1 and 2. A plurality of grooves 7 are formed so as to face each other in the circumferential direction, and each of the grooves 7 forms a mountain-shaped projection portion 8, 8, ... Therefore, between the flanges 5 and 5 of the adjacent cylinder liners 3 and 3, the distance between the grooves 7 and 7 facing each other is about three times wider than that between the protrusions 8 and 8. . In addition, in FIG.
Reference numeral 9 is a water jacket formed on the outer circumference of each of the cylinder liners 3.

Thus, in the above embodiment, the plurality of cylinder liners 3,
3,… Flanges 5,5 of adjacent cylinder liners 3,3
Since a plurality of notched grooves 7 extending in the cylinder bore centerline direction are formed in the circumferential direction on the outer periphery of the adjacent portion, the flanges 5 of the cylinder liners 3, 3 adjacent to each other by the groove shape of each groove 7 are formed. It is possible to widen the interval between 5 and 5. Therefore, the molten metal injected into the mold cavity during casting,
It is possible to promptly flow into the respective grooves 7 of the adjacent cylinder liners 3, 3 to eliminate the deterioration of the molten metal, and thereby to prevent the occurrence of casting defects such as molten metal boundary and blow holes due to the deterioration of the molten metal. The number of cracks can be reduced to reduce the frequency of occurrence of cracks. Further, since the grooves 7 are not formed over the entire circumference of the flange 5 but are formed partially, and the projecting size of the projecting portion 8 is set to be the same size as other places, The sealability of the gasket 6 interposed between the cylinder block 1 and the cylinder head can be ensured.

In the above embodiment, the adjacent cylinder liners 3 and 3 are arranged so that the grooves 7 and 7 on the outer periphery of the flanges 5 and 5 adjacent to each other face each other, but the present invention is not limited to this and, for example, in FIG. As shown in detail in enlargement, it is also possible to adopt a configuration in which the grooves 7 and the protrusions 8 are arranged so as to be opposed to each other. And in this case, the interval between the grooves 7 and 7 facing each other is
It is about twice as wide as the case where each groove 7 is not formed. Further, although not shown, it is also possible to adopt forming each of the grooves 7 in a semicircular shape or a trapezoidal shape.

(Effects of the Invention) As described above, according to the present invention, a plurality of flanges are formed that are adjacent to each other to form a cylinder bore of an engine and are surrounded by a casting, and a flange that forms a sealing surface with a gasket on the upper surface. Among the cylinder liners, a plurality of notched grooves extending in the cylinder bore center line direction are formed in the circumferential direction on the outer periphery of the adjacent portions of the flanges of the adjacent cylinder liners. While ensuring the sealing property of the gasket to be mounted, it is possible to improve the melt-flow property between the flanges of the adjacent cylinder liners of the molten metal during casting.

[Brief description of drawings]

The drawings show an embodiment of the present invention. FIG. 1 is an enlarged front view of a longitudinal section of a cylinder block, FIG. FIG. FIG. 4 is a view corresponding to FIG. 2 showing a modified example. 1 …… Cylinder block 3 …… Cylinder liner 4 …… Cylinder bore 5 …… Flange 6 …… Gasket 7 …… Groove

Claims (1)

[Scope of utility model registration request] 1. A light metal cylinder block in which a plurality of cylinder liners each having a flange for forming a sealing surface with a gasket on an upper surface to form a cylinder bore of an engine are adjacent to each other and are cast around, respectively. A cylinder block for an engine, wherein a plurality of notched grooves extending in the cylinder bore center line direction are formed in the circumferential direction on the outer periphery of the adjacent portions of the respective flanges of the cylinder liners that are adjacent to each other.