JPH10299570A - Cylinder head cooling structure - Google Patents

Abstract

(57) Abstract: Provided is a cylinder head cooling structure capable of more efficiently cooling a cylinder head of an internal combustion engine. A cylinder head has combustion chambers.
An intake / exhaust port jacket 12 extending in the arrangement direction of b, 2c and 2d is provided. Here, each combustion chamber 2
A concave portion 19 is provided at a position corresponding to a, 2b, 2c, 2d. The coolant flowing into the intake / exhaust port jacket 12 from the supply passage 15 flows through the interior of the intake / exhaust port jacket 12 in the lower portion of the recess 19 in the combustion chambers 2 a,
After flowing so as to be directed to the upper direction of 2b, 2c, 2d, it is discharged from the discharge port 20. In the cylinder head 1 according to the present embodiment, each of the combustion chambers 2a, 2
Three columns 21 are formed in a streamlined manner between b, 2c and 2d so as to guide the inside of the jacket 12 between the intake and exhaust ports downward.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a gasoline engine,
The present invention relates to a cooling structure of a cylinder head fixed to an upper part of a cylinder block of an internal combustion engine represented by a diesel engine or the like.

[0002]

2. Description of the Related Art Conventionally, as a cooling structure for a cylinder head of this type, for example, the one shown in FIG. 3 is known.

That is, the cylinder head 31 is fixedly joined to the upper side of a cylinder block (not shown in FIG. 3) provided with four combustion chambers 2a, 2b, 2c and 2d. In the cylinder head 31, a spark plug mounting hole 3 is formed at a position substantially corresponding to the center axis of each of the combustion chambers 2a, 2b, 2c, 2d. Is installed. Further, on the upper surface of the cylinder head 31, a total of five concave portions 39 are provided so as to sandwich the combustion chambers 2a, 2b, 2c, 2d in the arrangement direction of the combustion chambers 2a, 2b, 2c, 2d. . These recesses 39 are plug holes (sand holes) of the cylinder head 31.

On the other hand, in the cylinder head 31,
An intake port 4 is provided on each right side of the combustion chambers 2a, 2b, 2c, 2d in the drawing. The intake port 4 is open with two open ends 4a for each of the combustion chambers 2a, 2b, 2c, 2d. These open ends 4a are selectively opened and closed by intake valves (not shown).

Further, in the cylinder head 31,
An exhaust port 6 is provided on each left side of the combustion chambers 2a, 2b, 2c, 2d in the drawing. The exhaust port 6 is also opened with two open ends 6a for each of the combustion chambers 2a, 2b, 2c, 2d. These open ends 6a are selectively opened and closed by an exhaust valve (not shown).

Next, the cooling structure of the cylinder head 31 will be described. At a substantially central portion of the cylinder head 31, a jacket 33 between intake and exhaust ports is provided along the combustion chambers 2a, 2b, 2c and 2d, and a pair of exhaust port jackets extending parallel to the jacket 33 are provided on both sides thereof. 3
4 and an intake port jacket 35 are provided. The exhaust port jacket 34 is provided below the exhaust port 6, while the intake port jacket 35 is provided below the intake port 4. Cylinder head 31
In the lower part of the housing, supply passages 36, 37, 38 for opening cooling water from the water jacket of the cylinder block to the jackets 33, 34, 35, respectively, are opened upstream of the jackets 33, 34, 35, respectively. One is formed on each side (upper side in FIG. 3). Then, the jacket 3 passes through these supply passages 36, 37, 38.
Cooling water supplied to the jacket 3, 34, 35
By flowing through the insides 3, 34 and 35, the intake port 4, the exhaust port 6 of the cylinder head 31 and the periphery thereof are cooled. Then, after merging on the downstream side, it is discharged from the discharge port 40, guided to a radiator (not shown), and is again subjected to circulation.

[0007]

However, in such a cooling structure for a cylinder head, as described above, the recess 39 is formed in each of the combustion chambers 2a, 2b, 2c, 2d in the direction in which the combustion chambers 2a, 2b, 2c, 2d are arranged. , 2b, 2c, 2d, that is, between the cylinders,
The coolant flowing in the intake / exhaust port jacket 33 also flows downward between the cylinders provided with the concave portions 39 to be used for cooling the cylinder block 30 side. This will be further described with reference to FIG. FIG. 4 is a sectional view taken along line 4-4 in FIG.
Corresponds to a sectional view taken along line 3-3 in FIG.

As shown in FIG. 4, a concave portion 39 is provided in the jacket 33 between the intake and exhaust ports so as to protrude in a substantially U-shaped cross section (substantially cylindrical shape with a bottom). Therefore, the jacket 3 between the intake and exhaust ports is
The cooling fluid flowing into the jacket 33 follows the shape inside the jacket 33, that is, cools the upper surface of the cylinder block 30 in the lower portion 39 a of the concave portion 39.
It will be distributed inside.

On the other hand, the temperature which rises most with the operation of the internal combustion engine and requires cooling is the combustion chambers 2a, 2b, 2
It is near the position corresponding to c and 2d. However, in the above-described conventional cooling structure, the coolant flows downward in the cylinder head 31 between the cylinders, but in the vicinity of each of the combustion chambers 2a, 2b, 2c, and 2d, the combustion chambers 2a, 2c.
Since the gas flows in the upper part away from b, 2c and 2d, the same part could not be cooled effectively.

The coolant flowing near the upper portions of the combustion chambers 2a, 2b, 2c, and 2d collides with the inner wall 39b of the concave portion 39, and a part thereof becomes turbulent or stagnates. That is, the presence of the concave portion 39 also causes a reduction in the cooling effect.

The present invention has been made in view of such circumstances, and an object of the present invention is to provide a cylinder head cooling structure that can efficiently cool a cylinder head of an internal combustion engine.

[0012]

In order to achieve the above object, the invention according to claim 1 is arranged in a cylinder head of an internal combustion engine in which a plurality of cylinders are arranged in series and the arrangement of each of the cylinders is provided. A liquid passage for allowing the coolant to flow in a direction, and a concave portion provided on at least one cylinder of the cylinder head, for directing the flow direction of the coolant flowing through the liquid passage to the cylinder side. It is an abstract.

According to the first aspect of the present invention, the cooling fluid flowing through the liquid passage due to the concave portion has the highest temperature in the cylinder (combustion chamber) during operation of the internal combustion engine.
Since it is directed to the side, cooling can be performed more efficiently.

Further, the rigidity of the upper surface of the cylinder head can be improved by the concave portion provided on the upper surface of the cylinder head. According to a second aspect of the present invention, in the cooling structure for a cylinder head according to the first aspect, the concave portion has a mortar shape.

According to the second aspect of the invention, the collision of the cooling liquid flowing through the liquid passage with the lower surface of the concave portion is reduced,
Turbulence and stagnation can be suitably prevented. According to a third aspect of the present invention, in the cooling structure for a cylinder head according to the first or second aspect, the liquid passage is arranged between at least one cylinder of the cylinder head and flows in a flow direction of the cooling liquid. The gist of the invention is to provide a support having a linear shape and supporting the upper and lower portions of the passage.

According to the third aspect of the present invention, the coolant flowing through the liquid passage is rectified by the columns, and the coolant is suitably promoted to be directed toward the cylinder (combustion chamber) by the recess. be able to.

Further, since the upper and lower portions of the liquid passage are supported by the support columns, the rigidity of the cylinder head can be improved.

[0018]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment in which the present invention is embodied in a cooling structure for a cylinder head of a gasoline engine as an internal combustion engine will be described in detail with reference to FIGS.

FIG. 1 is a sectional view of a cylinder head 1 according to the present embodiment as viewed from above. The cylinder head 1 shown in FIG. 1 is provided above a cylinder block (not shown in FIG. 1) provided with a plurality (four in the present embodiment) of combustion chambers 2a, 2b, 2c and 2d. Bonded and fixed. In the cylinder head 1, the ignition plug mounting holes 3 are located at positions substantially corresponding to the center axes of the combustion chambers 2a, 2b, 2c, 2d.
And a spark plug 5 is mounted in each mounting hole 3. Furthermore, each of these combustion chambers 2 of the cylinder head 1
a, 2b, 2c, and 2d, four recesses 19 formed concentrically with the respective spark plug mounting holes 3
Is provided.

On the other hand, in the cylinder head 1, an intake port 4 is provided on each right side of each of the combustion chambers 2a, 2b, 2c, 2d in the drawing. The intake port 4 has two open ends 4 for each of the combustion chambers 2a, 2b, 2c, 2d.
It is open with a. These open ends 4a are selectively opened and closed by intake valves (not shown).

Further, in the cylinder head 1, an exhaust port 6 is provided on each left side of each of the combustion chambers 2a, 2b, 2c, 2d in the drawing. The exhaust port 6 also has two open ends 6 for each of the combustion chambers 2a, 2b, 2c, 2d.
It is open with a. These open ends 6a are selectively opened and closed by an exhaust valve (not shown).

Next, the cooling structure of the cylinder head 1 will be described. As shown in FIG. 1, the cylinder head 1 has a combustion chamber 2 mainly corresponding to each of the exhaust ports 6.
a, 2b, 2c, 2d as one of the liquid passages extending in the arrangement direction (vertical direction in FIG. 1).
1 is provided. Although the exhaust port jacket 11 is shown as a single passage in FIG. 1 for convenience, it is actually branched around the exhaust port 6 and communicates with each other while forming a complicated and complicated shape. It is provided as follows.

Similarly, in the cylinder head 1, the arrangement direction of the combustion chambers 2a, 2b, 2c, 2d (up and down in FIG. 1) is mainly provided between the exhaust ports 6 and the intake ports 4. The air inlet / exhaust port jacket 12 is provided as another liquid passage extending in the direction (i.e., direction). The intake / exhaust port jacket 12 is also shown as a single passage for convenience in FIG. 1, but is actually branched around the ignition plug mounting hole 3 and has a complicated and complicated shape. However, they are provided to communicate with each other.

Further, the cylinder head 1 has combustion chambers 2a, 2b, 2c,
An intake port jacket 13 is provided as yet another liquid passage extending in the 2d arrangement direction (the vertical direction in FIG. 1).

On the other hand, in the lower portion on the upstream side (upper side in FIG. 1) of the cylinder head 1, the cooling water from the water jacket of the cylinder block is opened to each of the jackets 11, 12, and 13, respectively. The supply passages 1415 and 16 for introducing into the 12 and 13 are formed one by one. The cooling water supplied to the exhaust port jacket 11, the intake / exhaust port jacket 12, and the intake port jacket 13 via these supply passages 14, 15, 16 flows through the respective jackets 11, 12, 13. After that, they are joined and led to the outlet 20, and the outlet 2
From 0, it is returned to a radiator not shown.

The above jackets 11, 12, 13
The cooling water flowing through the inside and guided to the radiator is cooled by the radiator and then supplied again to the water jacket of the cylinder block.

Next, the recess 19 will be described in detail with reference to FIG. FIG. 2 is a sectional view taken along line 2-2 in FIG. As described above, each of the combustion chambers 2a, 2b,
A concave portion 19 is provided at a position (FIG. 1) corresponding to 2c and 2d. As shown in FIG. 2, the concave portion 19 is provided so as to project from the upper surface side of the cylinder head 1 to the jacket 12 between the intake and exhaust ports in a substantially U-shaped (mortar shape) cross section. The coolant flowing from the supply passage 15 into the intake / exhaust port jacket 12 follows the inside of the intake / exhaust port jacket 12 along the shape of the jacket 12, that is, over the combustion chambers 2a, 2b, 2c, 2d. In the lower part of the concave portion 19 provided at a position corresponding to the above, the gas flows into the upper part of the combustion chambers 2a, 2b, 2c, 2d in a wavy shape so that the flow direction thereof is directed, and is then discharged from the discharge port 20. .

Further, in the cylinder head 1 according to the present embodiment, as shown in FIGS. 1 and 2, a streamline shape is formed between the combustion chambers 2a, 2b, 2c and 2d.
One support 21 is provided in such a manner that cooling water flowing in the jacket 12 between the intake and exhaust ports is rectified. Therefore, when the cooling water is rectified by the column 21, the flow of the cooling water is smoothly directed onto the combustion chambers 2a, 2b, 2c, and 2d. Further, as shown in FIG. 2, the column 21 also supports the upper surface 12a and the lower surface 12b of the jacket 12 between the intake and exhaust ports.

Next, the operation of the cooling structure for a cylinder head configured as described above will be described. As described above, the coolant flowing into the intake / exhaust port jacket 12 from the supply passage 15 flows through the intake / exhaust port jacket 12 along the shape of the jacket 12, that is, each of the combustion chambers 2a, 2b, 2c. , 2d, at the lower portion of the recess 19 provided at a position corresponding to the combustion chambers 2a, 2d.
It circulates in a wavy manner in the upper part of 2b, 2c, 2d so that the circulating direction is directed. Therefore, the upper portions of the combustion chambers 2a, 2b, 2c, 2d, which are likely to have high temperatures, are efficiently cooled.

When the cooling water is directed downward at the position of the concave portion 19, the cooling water collides with the upper surface 12a of the jacket 12 between the intake and exhaust ports. In the present embodiment, the upper surface 12a is a mortar. Due to the shape, such collisions are mitigated and associated turbulence and stagnation are prevented. Therefore, the cooling water flows smoothly. Further, a mortar-shaped recess 19 is provided in the cylinder head 1.
Is provided, the rigidity of the upper surface of the cylinder head 1 is improved.

On the other hand, the cooling water flowing through the jacket 12 between the intake and exhaust ports is rectified by the columns 21 between the combustion chambers 2a, 2b, 2c and 2d. By this rectification, the flow of the cooling water on the combustion chambers 2a, 2b, 2c, 2d is directed downward. Also,
The support 21 is provided on the upper surface 1 of the jacket 12 between the intake and exhaust ports.
Since the cylinder head 1 is provided so as to support between the lower surface 12a and the lower surface 12b, the overall rigidity of the cylinder head 1 is also improved.

As described in detail above, according to the present embodiment, the following effects can be obtained. The cylinder head 1 can be efficiently cooled by directing the flow of the cooling water downward on each of the combustion chambers 2a, 2b, 2c, 2d where the temperature tends to be high in the cylinder head 1.

· Jacket 12 between cooling water and intake / exhaust port
Of the cooling water can be mitigated, and the flow of cooling water can be smoothed. -Each combustion chamber 2a, 2b, 2
It can help to direct the flow on c, 2d downward.

The rigidity of the cylinder head 1 can be improved by the concave portions 19 and the columns 21. Note that the present embodiment is not limited to the above, and may be changed as follows.

In the above embodiment, each combustion chamber 2
Although four recesses 19 are provided corresponding to a, 2b, 2c, and 2d, they may be provided on any three or less of the combustion chambers 2a, 2b, 2c, and 2d.

In the above embodiment, the column 21 is provided in a streamline shape, but an appropriate guide may be provided on the column 21 to further promote the flow of the cooling water downward. .

In the above embodiment, three pillars 21 are provided at positions intermediate the combustion chambers 2a, 2b, 2c and 2d, but this position can be changed arbitrarily. The number may be four or more or two or less.

In the above embodiment, the cooling water flows in the jackets 11, 12, and 13 in the same direction. On the other hand, the flow direction of the cooling water may be arbitrary.

In the above embodiment, the three liquid passages are formed by the jackets 11, 12, and 13. However, the arrangement may be made by any number of liquid passages. -In the above-mentioned embodiment, each jacket 11, 1
Only one supply passage 14, 1 for each of 2, 13
5, 16 were provided. On the other hand, a plurality of supply passages may be provided for the jackets 11, 12, 13 along the flow direction of the cooling water.

In the above embodiment, two intake valves per cylinder (open end 4 of intake port 4)
a) and an exhaust valve (open end 6a of the exhaust port 6) is embodied in the cylinder head 1. However, any number of valves (open ends of each port) may be provided as long as one or more valves are provided. It may be.

In the above-described embodiment, the cooling structure according to the present invention is embodied in the cylinder head 1 of the in-line four-cylinder gasoline engine, but this is applied to the cooling of the cylinder head on at least one side of the V-type engine, for example. It may be embodied in a structure.

In the above embodiment, the cooling structure according to the present invention is embodied in the cylinder head 1 of the gasoline engine, but the cooling structure may be embodied in the cylinder head of the diesel engine.

[0043]

According to the first aspect of the present invention, the cooling fluid flowing through the liquid passage by the concave portion is directed to the cylinder (combustion chamber) side where the temperature tends to be the highest during operation of the internal combustion engine. The cooling can be performed more efficiently.

Further, the rigidity of the upper surface of the cylinder head can be improved by the concave portion provided on the upper surface of the cylinder head. According to the second aspect of the invention, the collision of the cooling liquid flowing through the liquid passage with the lower surface of the concave portion is mitigated, and turbulence and stagnation can be appropriately prevented.

According to the third aspect of the present invention, the coolant flowing through the liquid passage is rectified by the columns, and the coolant is favorably directed to the cylinder (combustion chamber) side by the recess. be able to.

Further, the support between the upper and lower portions of the liquid passage is supported by the support columns, so that the rigidity of the cylinder head can be improved.

[Brief description of the drawings]

FIG. 1 is a sectional view showing an embodiment of a cylinder head cooling structure according to the present invention.

FIG. 2 is a sectional view taken along the line 2-2 in FIG. 1;

FIG. 3 is a cross-sectional view showing an example of a conventional cylinder head cooling structure.

FIG. 4 is a sectional view taken along line 4-4 in FIG. 3;

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Cylinder head, 4 ... Intake port, 6 ... Exhaust port, 11 ... Exhaust port jacket, 12 ... Intake / exhaust port jacket, 12a ... Upper surface, 12b ... Lower surface, 13 ... Intake port jacket, 14, 15, 16 ... Supply Passage, 1
9 ... recess, 21 ... pillar.

Claims (3)

[Claims] 1. A liquid passage which is provided in a cylinder head of an internal combustion engine in which a plurality of cylinders are arranged in series and through which coolant flows in an arrangement direction of each of the cylinders, and on at least one cylinder of the cylinder head. And a recess for directing the flow direction of the coolant flowing through the liquid passage toward the cylinder. 2. The cooling structure for a cylinder head according to claim 1, wherein said recess has a mortar-like shape. 3. The cooling structure for a cylinder head according to claim 1, wherein the liquid passage is disposed between at least one cylinder of the cylinder head, and has a streamline shape in a flow direction of the cooling liquid. A cooling structure for a cylinder head, comprising: a supporting column for supporting a space between upper and lower portions of the passage.