JPS5833249Y2 - Internal combustion engine cooling structure - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a cooling structure that uniformly and effectively cools the cylinders by substantially equalizing the distribution of cooling water around all the cylinders of an internal combustion engine.

In recent years, in many water-cooled internal combustion engines, in order to make the cylinder block more compact, no special water duct (cooling water passage) is provided on the side of the cylinder block, and the duct is replaced by a water jacket around the cylinder. I'm starting to let it happen.

That is, in this type of cylinder block 1 as shown in FIGS. 1 and 2, for example, cooling water is cooled by a radiator or the like (not shown) and pumped by a water pump to each cylinder 2 on the front wall 3 of the block. The inflow flows from the inlet 6 located approximately on a line connecting the axis of the cylinder, and after colliding with the first cylinder 21 that is particularly close to the population 6, it is divided into the a direction and the b direction along the wall surface of the cylinder 21, and then flows into the left and right cylinders. The water flows into the water jackets 5a and 5b, flows out to the rear, and cools each cylinder 2.

However, in such a case, the cylinder 21 close to the inlet 6 is extremely cooled because the cooling water cooled by the radiator etc. directly collides with the cylinder 21, resulting in a temperature difference with the other cylinders 2. .

Also, after that, the respective water jackets) 5a and 5
The cooling water divided into sections b sequentially cools a large number of cylinders 2, but whether the cooling water is sufficiently and evenly cooled to the last cylinder 22 farthest from the inlet 6 will affect the amount of cooling water that flows into the cylinder head 10 along the way. It is something that will be done.

That is, in the illustrated flock 1, there are drain holes 8 to the head 10 for each cylinder 2 provided in the upper wall 9 of the block.
The water jacket on the left side of the figure) is small on the Sa side,
Assuming that the water jacket 5b on the right side is larger than this, the cooling water gradually escapes to the head 10 through the small drain hole 8a on the water jacket 5a side, and more than enough cooling water reaches the last cylinder 22. A large amount of water from the water jacket 5b side escapes to the cylinder head 10 through the large drain hole 8b, and as it flows later, a large amount of water escapes in this way, so that the cooling water to cool the right side of the cylinder 2 gradually becomes insufficient and the large drain hole 8b is drained. Since the side of the water jacket 5b that is provided is not sufficiently cooled, temperature differences occur not only between cylinders but also between individual cylinders, which is undesirable.

In view of the above points, the present invention aims to provide a cooling structure that distributes the amount of cooling water so that the temperatures of all cylinders are approximately equal, avoiding overcooling and insufficient cooling of specific cylinders.

Hereinafter, the present invention will be explained with reference to an embodiment shown in FIGS. 1, 3, and 4.

Incidentally, parts that are the same as those of the conventional example will be given the same designation.

1 is a cylinder block, 2 is its cylinder, 3.4 is the front wall and side wall, and 5 is a water jacket formed by each wall on the outside of cylinder 2. A water jacket (5a) is provided on the left side in FIG. 3, and a water jacket (5b) is provided on the right side.

Reference numeral 8 denotes a drain hole for the cylinder head 10 provided in the block upper wall 9 for each cylinder 2, with a small hole 8a formed on the water jacket 5a side and a larger hole 8b formed on the water jacket 5b side. ing.

As a result, when cooling water flows through the water jacket 5, more of the cooling water flows into the cylinder head 10 from the large water drain hole 8b on the right side than from the small water drain hole 8a on the left side.

Reference numeral 7 denotes an introduction member installed so that its center is approximately located on the line 30 of the front wall of the block, and has a protrusion 71 in the center to allow cooling water to be cooled by a cooling device such as a radiator (not shown) and pumped by a water pump. The main flow of the cooling water is divided by the V-shaped deflection portion 71A having the main flow in the direction of the left and right water jackets 5a and 5b without colliding directly with the cylinder 21 adjacent to the introduction member 7.
Introductory lower A formed by deflecting portion 71A and outer peripheral portion 72
and 7B.

In addition, the introduction member 7 has a small introduction lower A directed toward the water jacket 5 which has a small amount of cooling water passing through to the cylinder head 10, that is, the water jacket 5a that communicates with the small water drain hole 8a. A water jacket 5 with a large amount of cooling water, that is, a water jacket 5b that communicates with a large drain hole 8b.
The introduction lower B facing the water jacket is made thicker so that less cooling water flows through the water jacket 5a and more cooling water flows through the water jacket 5b.

In the above configuration, the cooling water pumped by the water pump is diverted by the deflection part 71A, and from the introduction lowers A and 7B to the left and right water jackets 5a and 5.
It flows out towards b.

Therefore, the cooling water cooled by the radiator or the like does not directly collide with the cylinder 21 adjacent to the inlet, so that the cylinder 21 is prevented from being overcooled.

Also, the amount of cooling water that flows into the cylinder head 10 in the middle of the water jacket 5 is larger than that of the water jacket 5a on the left side because the water jacket 5b on the right side in the figure communicates with a larger drain hole 8b. Therefore, there is a concern that the amount of water reaching the rear part decreases, causing a difference in temperature distribution between the left and right sides of the cylinder 2. However, in the present invention, a large introduction lower B is installed in the water jacket 5b on the right side, which communicates with the large drain hole 8b. Than,
Also, since the cooling water is made to flow from the small introduction lower A to the water jacket 5a that communicates with the small water drain hole 8a, a lot of cooling water flows to the right water jacket 5b, and even to the cylinder 2 at the rear. Since a sufficient amount of cooling water reaches the cylinder 2, the imbalance in temperature distribution between the left and right sides of the cylinder 2 can be reduced.

As described above, in the present invention, the cooling water from the water pump is divided by the introduction member 7 attached to the cylinder block wall surface 3 and flows toward the water jacket 5.
In addition, the size of the inlet port through which cooling water flows into the water jacket 5 is changed to a larger inlet lower B toward the water jacket 5b, where a large amount of cooling water passes through to the cylinder head 10, and a smaller inlet lower A toward the water jacket 5a, where less water passes through. Therefore, the cylinder 21 near the inlet is not overcooled, and the unbalance in the temperature distribution around cylinder 2, which conventionally increases toward the rear cylinder, can be reduced, resulting in highly reliable cooling. It can provide structure.

In this embodiment, the introduction member 7 is positioned on a line connecting the axes of the cylinders 2 of the cylinder flock front wall 3, but the introduction member 7 is not limited to this. It can also be attached to.

In this case, the introduction member 7 is attached to the side wall 4 using the cylinder 20.
Needless to say, when the two cylinders are located between them, the cooling water from the water pump does not directly collide with both cylinders.

Furthermore, the introduction member 7 may be manufactured integrally with the cylinder block 1, and the number of introduction ports is not limited to two.

Furthermore, to direct the flow of cooling water toward the water jacket 5, a current transformation plate 74 made of metal or the like is attached to the rear surface 73A of the introduction member 7 at the rear of the protrusion 71 on the Niji cylinder 21 side, as shown in FIGS. 5 and 6. Alternatively, the T-shaped deflecting portion 71A may be formed.

In addition, although the present invention has been explained using a multi-cylinder engine, it goes without saying that the same effects as described above can be obtained even when applied to a single-cylinder engine.

[Brief explanation of drawings]

Figure 1 is a vertical sectional view of the cylinder block, Figures 2 and 3 are
The figure is a cross-sectional view of Figure 1, Figure 2 shows the conventional example, and Figure 3 shows the conventional example.
The figure shows one embodiment of the present invention, with the main parts enlarged, Fig. 4 is a view taken from the front arrow of Fig. 3, Fig. 5 shows another embodiment of the present invention, and Fig. 6 shows an enlarged view of the main parts. is a view taken in the direction of the arrow in FIG. 1 Niji cylinder block, 2 Niji cylinder, 3.4 Front wall and side wall of Niji cylinder block, 5: Water jacket, 7: Introduction member, 7A, 7A, 7B. 7B': Inlet, 71. 71': Protrusion, 73.73B
: Rear surface of introduction member, 8a, 8b: Drain hole.

Claims (1)

[Scope of utility model registration request] In a cylinder block in which a water jacket is provided around the cylinder and a drain hole is provided in the cylinder head that communicates with the water jacket, the cooling water from the water pump is prevented from colliding directly with the cylinder by the deflection part and is directed to the water jacket. An introduction member is provided on the wall surface of the cylinder block, and the introduction member is formed with an introduction port so as to divert the water toward the cylinder head. A cooling structure for an internal combustion engine, characterized in that the inlet facing the water jacket side communicating with the water jacket through a small drain hole is made small.