JPH0443845A - Cylinder block for internal combustion engine - Google Patents

Abstract

PURPOSE:To obtain a small sized light weight engine and improve cooling efficiency and strength between cylinder bores by providing a cooling water passage of a cooling water supply system independent of a water jacket at the constricted part of a siamese part of adjacent cylinders. CONSTITUTION:Cooling water passages 9 along the cylinder 4 axis are provided at constricted parts 14, and siamese part 7 is forcedly cooled, as a result of this, cooling efficiency between cylinders 4 is improved. The cooling water passage 9 is connected to a water gallery formed in relatively low temperature part and separated from a water jacket, therefore, cooling water of lower temperature than that of the water jacket and higher flow speed can be supplied. As the temperature of cylinder 4 on the water jacket side is lower than the temperature of siamese part 7, cooling water capacity and flow of the water jacket 5 can be reduced. Further, by providing a passage forming part 9A at the constricted part 14 of the siamese part 7, the passage forming part functions as a reinforcing rib.

Description

[Detailed Description of the Invention] <Industrial Application Field> The present invention relates to a cylinder block for an internal combustion engine, and in particular, to a cylinder block for an internal combustion engine.
Regarding the structure of the cooling water supply system.

<Prior Art> Conventionally, the structure of the cylinder block of an internal combustion engine (hereinafter referred to as engine) is the full jacket type cylinder block shown in Japanese Utility Model Application No. 59-168554 and Japanese Utility Model Application No. 63-L38419, etc. Kaisho 60-18
Siamese type cylinder blocks shown in Japanese Unexamined Utility Model Publication No. 240, Japanese Unexamined Utility Model Publication No. 55-170437, Japanese Unexamined Utility Model Publication No. 58-2342, Japanese Unexamined Utility Model No. 63-193724, and Japanese Unexamined Utility Model Publication No. 57-52654 are known. ing.

<Problems to be Solved by the Invention> For example, a full jacket type cylinder block 20 as shown in FIG. There is a problem in that it increases the overall length.

On the other hand, in the Siamese type cylinder block 23 as shown in FIG. 9, adjacent cylinders 24 are connected to each other, and there is no cooling water passage between the cylinders 24,
4. Is it possible to make the engine smaller and lighter by shortening the interval? As shown in the figure, the cooling water flowing inside the water jacket 26 at the constricted part 25 of the joint part between the cylinders 24 (hereinafter referred to as the Siamese part). There is a problem in that the heat generated between the cylinders 24 cannot be sufficiently absorbed, and the temperature between the cylinders 24 increases, causing the engine to seize or the like.

In addition, the Siamese type cylinder block 27 shown in FIG. 10 is one in which the Siamese portions 29 between the cylinders 28 are machined to provide cooling water passages 30, or the cooling water passages 30 are small. In addition, due to stagnation of cooling water, sufficient cooling effect could not be obtained, and cylinder 2
Since the machining is performed between the cylinders 28, the strength between the cylinders 28 is reduced, causing abnormal deformation of the cylinder bores.

Furthermore, the cylinder blocks shown in FIGS. 9 and 10 have the problem that the cooling water flow rate increases because the cooling water is supplied to the constricted portions of the Siamese portions between the cylinders, that is, to the stagnation portions. There is.

Therefore, in view of the above-mentioned conventional problems, the present invention provides a cooling water passage of a cooling water supply system independent of the water jacket at the constriction of the Siamese portion between the cylinders in a Siamese type cylinder block. The objective is to improve cooling efficiency between cylinder bores and improve strength while making the engine smaller and lighter.

<Means for Solving the Problems> For this reason, the present invention provides a Siamese-shaped cylinder block in which adjacent cylinders are connected to each other and a constricted portion is provided at this joint, in which a cylinder is attached to the constricted portion. Separately from the water jacket that cools the cooling water, a passage forming part is integrally formed with a cooling water passage along the cylinder center axis direction, and a passage forming part is formed independently in the direction of the cylinder row and below the water jacket to cool the cooling water. A water gear rally communicating with the passage is provided, and the cooling water passage and the water gear rally form a cooling water supply system independent of the water jacket.

<Function> In the conventional Siamese type cylinder block, there is a constricted part in the Siamese part, which causes cooling water to stagnate in this part, resulting in poor cooling efficiency of the Siamese part.

In the present invention, a cooling water passage along the cylinder center axis is provided in this constricted portion to forcibly cool the Siamese portion, thereby improving the cooling efficiency between the cylinders.

The cooling water in this cooling water passage is connected to a water gear rally formed in a relatively low-temperature part, and is separated from the water jacket, so the cooling water is cooled at a lower temperature and has a faster flow rate than the cooling water in the water jacket. Can you supply water?

Furthermore, since the temperature on the water jacket side of the cylinder is lower than the temperature at the Siamese portion, the cooling water capacity and flow rate of the water jacket can be reduced.

Further, by providing a passage forming portion at the constriction of the Siamese portion, the passage forming portion functions as a reinforcing rib, so that the strength of the Siamese portion can be improved.

<Example> Embodiments of the present invention will be described below with reference to the drawings.

1 to 4, a cylinder block 1 is formed from a cylinder portion 2 and a crankcase portion 3. As shown in FIGS.

The cylinder portion 2 is formed of a cylinder 4 on which a piston slides, a water jacket 5 serving as a cooling water passage for cooling the cylinder 4, and an outer wall 6 of the water jacket.

Adjacent cylinders 4 are connected to each other to form a Siamese portion 7. This Siamese portion 7 has a constricted portion J4.

Here, a passage forming part 9A is integrally formed in the constricted part 14, in which a cooling water passage 9 along the central axis direction of the cylinder 4 is provided separately from the water jacket 5 that cools the cylinder 4. The water passage 9 communicates with a water gear rally IO that is formed independently below the water jacket 5 in the cylinder row direction.

A cooling water supply system independent of the water jacket 5 is formed by the cooling water passage 9 and the water gear rally 10.

Cooling water is supplied from the cooling water port 11 to the water jacket 5 and from the cooling water port 12 to the cooling water passage 9.

Next, the functions and effects of this configuration will be explained.

In conventional Siamese-type cylinder blocks, there is a constricted part in the Siamese part, which causes cooling water to stagnate in this part, and as mentioned above, the cooling efficiency of the Siamese part is poor.

In the above embodiment, the cooling water passage 9 is provided along the central axis of the cylinder 4 in this constricted portion to forcibly cool the Siamese portion 7, thereby improving the cooling efficiency between the cylinders 4.

The cooling water in this cooling water passage 9 is connected to a water gear rally 10 formed in a relatively low temperature section, and is separated from the water jacket 5, so that the cooling water is at a lower temperature than the cooling water in the water jacket 5. It is possible to supply cooling water with a high flow rate.

Further, since the temperature on the water jacket 5 side of the cylinder 4 is lower than the temperature of the Siamese portion 7, the cooling water capacity and flow rate of the water jacket 5 can be reduced.

Further, by providing the passage forming portion 9A in the constricted portion 14 of the Siamese portion 7, the passage forming portion 9A functions as a reinforcing rib, which has the advantage of improving the strength of the Siamese portion 7.

In this embodiment, the cooling water flows from the cylinder block 1 to the cylinder head (the fourth
(see figure), there is no problem with a configuration in which the flow flows from the cylinder head to the cylinder block 1.

Next, another embodiment of the present invention will be described with reference to FIGS. 5 to 7.

In the embodiment shown in FIGS. 5 and 6, cooling water is not forcibly supplied to the water jacket 5, and a so-called boiling cooling method is used.

That is, since the temperature of the portion of the cylinder 4 other than the Siamese portion 7 is lower than that of the Siamese portion 7, this portion can be cooled by boiling.

Thereby, the capacity and flow rate of cooling water supplied into the engine can be reduced.

In this embodiment as well, the cooling water is configured to flow from the cylinder block 1 to the cylinder head (6th
(see figure), there is no problem with a configuration in which the flow flows from the cylinder head to the cylinder block 1.

In the embodiment shown in FIG. 7, an orifice 16 is provided in the cooling water volume 1 of the water jacket 5.

According to this configuration, the flow rate of cooling water to the water jacket 5 can be reduced and the flow rate to the water gear rally 10 can be increased, thereby improving the cooling efficiency between the cylinders 4.

Note that the configuration of the above embodiment does not indicate any structural limitations of the present invention, and the point is that the cylinder block is a Siamese-shaped cylinder block in which adjacent cylinders are connected to each other and a constricted portion is formed at this joint. In addition to integrally molding a passage forming part in which a cooling water passage is provided along the direction of the central axis of the cylinder separately from the water jacket for cooling the cylinder in the constricted part, and independently in the direction of the cylinder row and below the water jacket. A water gear rally may be formed and communicated with the cooling water passage.

<Effects of the Invention> As explained above, according to the cylinder block for an internal combustion engine according to the present invention, the joints between adjacent cylinders (
What is an overjacket that consists of a cooling water passage provided in a passage forming part integrally molded in the constriction of the Siamese part) and a water gear rally formed independently below the water jacket in the direction of the cylinder row? Since an independent cooling water supply system is formed, it is possible to prevent temperature rise between cylinders, reduce the size and weight by shortening the distance between cylinders, improve the strength between cylinders, and reduce the flow rate of cooling water. The usefulness that can be achieved is great.

[Brief explanation of the drawing]

FIG. 1 is a perspective view showing an embodiment of a cylinder block for an internal combustion engine according to the present invention, FIG. 2 is a longitudinal sectional view of the same embodiment,
FIG. 3 is a plan view of the same embodiment, FIG. 4 is a schematic diagram of the cooling water passage in the above embodiment, FIG. 5 is a plan view of another embodiment, and FIG. 6 is a schematic diagram of the cooling water passage in the same embodiment. A schematic diagram, FIG. 7 is a schematic diagram of a cooling water passage in another embodiment, FIG. 8 is a plan sectional view of one conventional example, FIG. 9 is a plan view of another conventional example, and FIG. 1θ (a) 10 is a longitudinal sectional view of yet another conventional example, and FIG. 10(b) is a plan view of the same embodiment. l...Cylinder Pro 5...Water Shake 9...Cooling water passage Water gear rally

Claims (1)

[Claims] Adjacent cylinders of an internal combustion engine are connected to each other,
In a Siamese-shaped cylinder block having a constricted portion at the joint, a passage forming portion in which a cooling water passage along the cylinder center axis direction is provided is integrally formed in the constricted portion, in addition to the water jacket for cooling the cylinder. At the same time, a water gallery is formed independently below the water jacket in the cylinder row direction and communicates with the cooling water passage, and the cooling water passage and the water gallery provide cooling that is independent of the water jacket. A cylinder block for an internal combustion engine, characterized in that it forms a water supply system.