JPH07224716A - Cooling device for siamese type cylinder block - Google Patents

Abstract

PURPOSE:To improve the cooling efficiency of a common cylinder wall part without damaging the workability in a cooling water passage of a Siamese type cylinder block. CONSTITUTION:A cooling water jacket 10 of a cylinder block 1 is folded back in such a manner as to go round the periphery of the exhaust port side and the periphery of the intake port side in the cylinder wall column to be communicated with a cooling water jacket 13 of a cylinder head 3. A substantially Y- shaped cooling water passage 14 is bored in a part of a common cylinder wall 9 between cylinders in such a manner that one upper end part 14a is opened to an exhaust port side communicating path 15, the other upper end part 14b is opened to an intake port side communicating path 16, and the lower end part 14c is opened to a part on the exhaust port side. The exhaust port side communicating path 15 is blocked up by a gasket 5 between the cylinder block and the cylinder head, whereby the cooling efficiency for a part of the common cylinder wall 9 can be improved without damaging the workabillty of boring the substantially Y-shaped cooling water passage.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a multi-cylinder internal combustion engine in which a cylinder wall of each cylinder of a cylinder block is
The present invention relates to a so-called siamese type cylinder block configured so as to be partially integrated in a portion between adjacent cylinders, and relates to a cooling device for the siamese type cylinder block.

[0002]

2. Description of the Related Art If a cylinder block in a multi-cylinder internal combustion engine is constructed in a Siamese type, the interval between the cylinders can be narrowed, which has the advantage of reducing the size and weight of the internal combustion engine. In the Siamese type cylinder block, the cooling performance of the cylinder cylinder wall of each cylinder, which is integrated between the adjacent cylinders, of the common cylinder cylinder wall is significantly reduced. Of the lubricating oil increases, and not only the consumption of lubricating oil increases, but also seizure occurs due to poor lubrication.

[0003] Therefore, as a prior art, the actual development Sho 59-1
In Japanese Patent No. 27852, a common Y-shaped cylinder wall, which is integrated between adjacent cylinders of the cylinder cylinder wall in each cylinder, is shown in FIG. An exhaust port-side communication passage that connects the cooling water jacket of the cylinder block and the cooling water jacket of the cylinder head to the cooling water passage at one of the two upper ends of the Y-shaped cooling water passage on the exhaust port side. Of the cooling water jacket of the cylinder block, and the other upper end of the cooling water jacket of the cylinder block and the cooling water jacket of the cylinder head are opened at the intake port side, respectively. By piercing so as to open to the portion on the exhaust port side and flowing cooling water into this Y-shaped cooling water passage It proposes to actively cool the portion of the common cylinder tube wall.

[0004]

By the way, in the conventional Siamese type cylinder block, in order to improve the cooling property of the cylinder block, for example,
As described in Japanese Utility Model Laid-Open No. 63-147543, the cooling water jacket in the cylinder block is
After going around the exhaust port side of the cylinder cylinder wall row integrated with each other and then folding back around the intake port side of the cylinder cylinder wall row, it is connected to the cooling water jacket in the cylinder head. A U-turn type cooling water jacket is used.

When the above-mentioned prior art is applied to the cooling water jacket of the Siamese type cylinder block configured as the U-turn type cooling water jacket as described above, the following will be described. However, there is a problem in that it is not possible to achieve sufficient cooling of the portion of the common cylinder cylinder wall. That is, in the case where the cooling water jacket in the Siamese type cylinder block is configured as the U-turn type cooling water jacket as described above, the cooling water pressure distribution is such that the cooling water in the cylinder block is distributed along with the cooling water flow. It is the highest in the portion of the jacket on the exhaust port side, then the lowest in the portion of the cooling water jacket in the cylinder block on the intake port side, and the lowest in the portion of the cylinder head in the cooling water jacket. is there.

Therefore, in the above-mentioned prior art, the pressure difference between the communication passages connecting the cooling water jacket of the cylinder block and the cooling water jacket of the cylinder head across the exhaust port side communication passage is large. A large amount of cooling water flows in the communication passage on the exhaust port side, and as a result, one of the upper end portions of the substantially Y-shaped cooling water passage formed in the cylinder wall of the common cylinder is connected to the communication passage on the exhaust port side. Since the amount of cooling water flowing out from or inflowing from one of the upper ends that are open to the opposite side is small, there is a portion where the cooling water does not sufficiently flow in a part of the substantially Y-shaped cooling water passage. It was not possible to achieve sufficient cooling of the portion of the common cylinder cylinder wall by the substantially Y-shaped cooling water passage.

According to the present invention, when the cooling water jacket in the siamese type cylinder block is formed into a U-turn type cooling water jacket, sufficient cooling is performed in the portion of the common cylinder cylinder wall of the siamese type cylinder block. It is a technical subject to ensure that this can be achieved by the substantially Y-shaped cooling water passage provided.

[0008]

In order to achieve this technical object, the present invention discloses that "a cooling water jacket in a cylinder block having a cylinder head fastened to an upper surface thereof is integrated with each other on an exhaust port side in a cylinder cylinder wall row. A U-turn type cooling water jacket is provided which circulates around and then folds back around the intake port side of the cylinder cylinder wall row to communicate with the cooling water jacket in the cylinder head. A substantially Y-shaped cooling water passage is provided in a common cylinder cylinder wall between the cylinders, and one upper end of the two upper ends of the Y-shaped cooling water passage is exhausted from a cooling water jacket of the cylinder block. Place the other upper end in the exhaust port side communication passage that connects the port side part and the cylinder head cooling water jacket. Each of the cooling water jackets in the Linda block has an opening in a communication passage that connects the intake port side of the cylinder block with the cooling water jacket of the cylinder head. In the Siamese type cylinder block formed by opening so as to open in the portion of FIG. 3, the exhaust port side communication passage is closed with a gasket inserted between the cylinder block and the cylinder head. did.

[0009]

[Operation] In this configuration, as described above, the pressure distribution in the cooling water is highest in the portion of the cooling water jacket of the cylinder block on the exhaust port side with the flow of the cooling water, and then in the cylinder block. The cooling water jacket has a form in which it is low in the intake port side portion and is lowest in the cooling water jacket portion in the cylinder head.

Therefore, as described above, by closing the exhaust port side communication passage in which one upper end portion of the substantially Y-shaped cooling water passage is open, the portion from the exhaust port side of the cooling water jacket in the cylinder block is described above. The flow of the cooling water through the communication passage on the exhaust port side to the cooling water jacket in the cylinder head is stopped, and the cooling water having the highest pressure in the portion on the exhaust port side of the cooling water jacket in the cylinder block is substantially Y. After flowing into both of the upper end and the lower end of the substantially Y-shaped cooling water passage into the character-shaped cooling water passage, the cylinder block is introduced from the other upper end of the substantially Y-shaped cooling water passage. Of the cooling water jacket in the intake port side communicating with the intake port side where the pressure is low. From the whole of the substantially Y-shaped cooling water passage, it is possible to ensure a sufficient flow of cooling water.

Moreover, since the exhaust port side communication passage is closed by the gasket inserted between the cylinder block and the cylinder head, the exhaust port side communication passage is closed, so that the cylinder block of the cylinder block is closed. Drilling from the upper surface does not prevent the formation of the substantially Y-shaped cooling water passage.

[0012]

Therefore, the cooling performance for the portion of the common cylinder cylinder wall in the Siamese type cylinder block is improved.
There is an effect that it is possible to surely improve the workability of forming a substantially Y-shaped cooling water passage in the portion without impairing the workability.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT An embodiment of the present invention will be described below with reference to the drawings of FIGS. In this figure, reference numeral 1 designates a cast cylinder block having a plurality of cylinders 2 arranged in a line,
Reference numeral 3 indicates a cylinder head fastened to the upper surface of the cylinder block 1 by a plurality of head bolts 4,
The upper surface of the cylinder block 1 and the cylinder head 3
A gasket 5 for sealing is inserted between the lower surface and the lower surface.

Each of the cylinders 2 is attached to the cylinder head 3.
And an intake port 7 for each cylinder 2 is formed so as to open at the other side surface 3b. On the other hand, the cylinder block 1 is constructed in a Siamese type in which the cylinder cylinder wall 8 of each cylinder 2 is partially integrated at a portion between adjacent cylinders 2, and this portion is made into a common cylinder cylinder wall 9. Inside the cylinder block 1, a cooling water jacket 10 is formed so as to surround substantially the entire circumference of the cylinder cylinder wall 8 integrated with each other.
The cooling water jacket 10 travels from a cooling water inlet 11 from a radiator provided at one end of the cylinder block 1 around the exhaust port 6 side of the cylinder cylinder wall 8 row, and then the intake port in the cylinder cylinder wall 8 row. After being folded back so as to circulate around the 7 side, it is configured as a U-turn type cooling water jacket that is connected to the cooling water jacket 13 in the cylinder head 3 through the cooling water main outlet 12.

Further, a substantially Y-shaped cooling water passage 14 is provided in a portion of the common cylinder tubular wall 9 between the respective cylinders 2, and two upper end portions 14a, 14a of the Y-shaped cooling water passage 14 are provided.
One of the upper ends 14a of the cylinder blocks 14b is the cylinder block 1
Of the cooling water jacket 10 on the exhaust port 6 side and the cooling water jacket 13 of the cylinder head 3
An intake port in which the other upper end portion 14b communicates a portion 10b on the intake port 7 side of the cooling water jacket 10 in the cylinder block 1 and the cooling water jacket 13 of the cylinder head 3 with an exhaust port side communication passage 15 which communicates with the cooling water jacket 13. Each side communication passage 16 has an opening, and one lower end 14
c is a cooling water jacket 10 in the cylinder block 1.
It is formed so as to open in the portion 10a on the exhaust port 6 side. The substantially Y-shaped cooling water passage 14 is
After the cylinder block 1 is cast, the inside of the exhaust port side communication passage 15 and the intake port side communication passage 16
It is drilled by drilling.

The gasket 5 inserted between the cylinder block 1 and the cylinder head 3 is provided with a blind portion 5a at a portion corresponding to the exhaust port side communication passage 15, and this blind portion 5a is used. , The exhaust port side communication passage 1
5 is closed. In this configuration,
Most of the cooling water that has flowed into the cooling water jacket 10 in the cylinder block 1 from a radiator (not shown) through the cooling water inlet 11 flows through the portion of the cooling water jacket 10 on the exhaust port 10a side in the cylinder row direction. Next, the intake port 10 of the cooling water jacket 10
After returning to the portion on the b side and flowing through the portion on the intake port 10b side in the cylinder row direction, it flows out to the cooling water jacket 13 in the cylinder head 3 via the cooling water main outlet 12.

The pressure distribution of the cooling water thus flowing is highest in the portion 10a of the cooling water jacket 10 in the cylinder block 1 on the exhaust port 6 side, and then in the cooling water jacket 10 in the cylinder block 1.
Among them, the shape is such that it is low in the portion 10b on the intake port 7 side and is lowest in the portion of the cooling water jacket 13 in the cylinder head 3.

In this case, when the exhaust port side communication passage 15 is not blocked as in the above-mentioned prior art, the portion of the cooling water jacket 10 of the cylinder block 1 on the exhaust port 6 side and the cylinder. The pressure difference between the head 3 and the cooling water jacket 13 is large, and the exhaust port side communication passage 1 that communicates between them is provided.
Due to the pressure difference, a large amount of cooling water flows in the inside of 5, and as a result, both upper end portions 14 of the substantially Y-shaped cooling water passage 14 formed in the common cylinder cylinder wall 9 are formed.
Of the a and 14b, the amount of the cooling water that flows out or flows in from one upper end portion 14a that opens to the exhaust port side communication passage 15 becomes considerably small, so that a sufficient amount of the common cylinder tube wall 9 is provided. Cooling will not be achievable.

On the other hand, when the exhaust port side communication passage 15 is closed as in the present invention, from the portion 10a of the cooling water jacket 10 of the cylinder block 1 on the exhaust port 6 side to the exhaust port side. Cooling water jacket 13 in cylinder head 3 through communication passage 15
Flow of cooling water to the cylinder block 1 is stopped.
The cooling water having the highest pressure in the portion 10a on the exhaust port 6 side of the cooling water jacket 10 in FIG.
The substantially Y-shaped cooling water passage 14 is provided in the character-shaped cooling water passage 14.
Of the cooling water jacket 10 in the cylinder block 1 having a lower pressure than the other upper end 14b of the substantially Y-shaped cooling water passage 14 after flowing in from both the upper end 14a and the lower end 14c. Intake port-side communication passage 16 that communicates with the portion 10b on the port 7 side
Since it will flow out to the above, the substantially Y-shaped cooling water passage 1
It is possible to secure a sufficient flow of cooling water in the whole of No. 4.

Moreover, the communication passage 15 on the exhaust port side
Is configured to be closed by the blind portion 5a provided on the gasket 5 inserted between the cylinder block 1 and the cylinder head 3, whereby the exhaust port side communication passage 15
Therefore, it is possible to avoid obstructing the work of drilling the substantially Y-shaped cooling water passage 14 from the upper surface of the cylinder block 1 to block the above.

[Brief description of drawings]

FIG. 1 is a vertical sectional front view showing an embodiment of the present invention.

FIG. 2 is a plan view taken along line II-II of FIG.

3 is an enlarged sectional view taken along line III-III of FIG.

[Explanation of symbols]

1 Cylinder Block 2 Cylinder 3 Cylinder Block 5 Gasket 6 Exhaust Port 7 Intake Port 8 Cylinder Cylinder Wall 9 Common Cylinder Cylinder Wall 10 Cylinder Block Cooling Water Jacket 11 Cooling Water Inlet 12 Cooling Water Main Outlet 13 Cylinder Head Cooling Water Jacket 14 Y-shaped cooling water passage 15 Exhaust port side communication passage 16 Intake port side communication passage 5a Gasket blind part

Claims (1)

[Claims] 1. A cooling water jacket in a cylinder block having a cylinder head fastened to the upper surface is circulated around the exhaust port side in a cylinder cylinder wall row integrated with each other,
Next, after being folded back so as to circulate around the intake port side of the cylinder cylinder wall row, a cooling water jacket of a U-turn shape is formed so as to communicate with the cooling water jacket of the cylinder head, and between the cylinders. A substantially Y-shaped cooling water passage is provided in the common cylinder wall, and one of the two upper ends of the Y-shaped cooling water passage is connected to the exhaust port side of the cooling water jacket of the cylinder block. And the cooling water jacket of the cylinder head to the exhaust port side communication passage, the other end of the intake port side of the cooling water jacket of the cylinder block and the cooling water jacket of the cylinder head Open each of the communication passages and remove one lower end of the cooling water jacket in the cylinder block. In a Siamese type cylinder block formed so as to open in a port side portion, the exhaust port side communication passage is configured to be closed by a gasket inserted between the cylinder block and the cylinder head. A cooling device for a Siamese type cylinder block characterized by the above.