JP2003184643A - Cooling water passage structure for cylinder head - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a cooling water passage structure for a cylinder head in which stagnation does not occur. <P>SOLUTION: An upper cooling water passage 24 and a lower cooling water passage 25 are formed with a compartment wall 23 interpolated between an upper wall 21 and a lower wall 22. A rib 41 opposing cooling water flows A1, A2 which flow from respective adjacent cylinder sides while corresponding to positions among the cylinders is provided at the lower cooling water passage 25. In addition, communicating passages 51a, 51b for communicating the lower cooling water passage 25 with the upper cooling water passage 24 are provided on the respective cylinder sides adjacently to the rib 41. Thus, since the respective cooling water flows of the adjacent cylinders are prevented from intervening in each other not to cause stagnation, the cylinder head with excellent cooling efficiency can be achieved. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cooling water passage structure for a cylinder head, and more particularly to a cooling water passage structure for a cylinder head in which cooling water flows from adjacent cylinders do not interfere with each other.

[0002]

2. Description of the Related Art Conventionally, a cooling water passage structure formed in a cylinder head is provided with a plurality of systems of cooling water passages, for example, an upper cooling water passage and a lower cooling water passage are provided in upper and lower two systems. Cooling water passage structures are well known. Above and below 2
An example of the cooling water passage structure having a system configuration is shown in FIG.
The cooling water passage structure shown in FIG. 9 and the cooling water passage structure shown in FIGS. 10 and 11 can be mentioned.

The cylinder head 100 shown in FIGS. 6-9.
In this cooling water passage structure, an upper cooling water passage 104 and a lower cooling water passage 105 are formed between an upper wall 101 and a lower wall 102 with a partition wall 103 interposed therebetween. The upper cooling water passage 104 and the lower cooling water passage 105 are formed in the partition wall 103 so as to correspond to the positions between the cylinders.
I am communicating with 6. In each drawing, 107 is a head bolt through hole, 108 and 109 are intake ports,
110 and 111 are exhaust ports, and 112 is a mounting portion of the fuel injection nozzle.

The cooling water passage structure of the cylinder head 200 shown in FIGS. 10 and 11 has an upper cooling water passage 204 and a lower cooling water passage with a partition wall 203 sandwiched between an upper wall 201 and a lower wall 202. 205 is formed.
In this example, the upper wall 201 corresponds to the position between the cylinders.
The ribs 206 extending from to the lower wall 202 are provided to strengthen the rigidity of the lower wall 202. The upper cooling water passage 204 and the lower cooling water passage 205 are connected to the rib 20.
6, the communication passage 2 formed in the partition wall 203
I am communicating with 07. In the figure, reference numeral 208 is a head bolt through hole, 209 and 210 are intake ports, 211 and 212 are exhaust ports, and 213 is a mounting portion of a fuel injection nozzle.

[0005]

Needless to say, in such a cooling water passage structure of a plurality of systems, it is ideal from the viewpoint of cooling efficiency that the cooling water flow in each cylinder portion flows in an orderly manner without stagnation. As an example, the cooling water passage structure shown in FIGS. 6 to 9 will be described. As shown in FIGS. 7 and 8, each cylinder is effectively cooled between the ports of the lower cooling water passage 105. As indicated by arrows a1 and a2
When the cooling water flows like the above, that is, when the adjacent cylinders flow in the directions opposite to each other, the cooling water flowing out from between the ports equally passes through the communication passage 106 formed at the position between the cylinders and joins. And then to the upper cooling water passage 104, the arrow b
It is ideal to go up like this.

However, in this cooling water passage structure,
The cooling water flow flowing out between the ports on one cylinder side and the cooling water flow flowing out between the ports on the other cylinder side directly collide with each other, and as shown by arrows c and d in FIG. However, it may be pushed by the strong water flow d, and the cooling water flow may stagnant between the ports of the cylinder having the weaker water flow as indicated by e.

In this respect, in the cooling water passage structure illustrated in FIGS. 10 and 11, since the cooling water flows f1 and f2 flowing out between the ports of the respective cylinders hit the ribs 206 provided between the cylinders, they directly collide with each other. It is configured so that they do not match, and the respective water streams merge and pass through the communication passage 207. However, the strong water flow f2 impinges on the rib 206 and then rushes to the opposite side of the rib 206,
Further, it may flow into the water flow side where the momentum is weak, and as shown by h in FIG. 11, the cooling water flow may stagnant on the side of the cylinder that is also weak.

The present invention has been made in view of the above circumstances, and reliably prevents the stagnation of the cooling water flow in the cooling water passage to smooth the cooling water flow and improve the cooling efficiency of the cylinder head. An object of the present invention is to provide a cooling water passage structure for a cylinder head.

[0009]

A cooling water passage structure for a cylinder head according to the present invention which achieves the above object,
The invention described above is a cylinder head for covering a cylinder block in which a plurality of cylinders are formed in parallel, and a cooling water passage structure for a cylinder head in which at least two systems of cooling water passages are formed, Among the cooling water passages, at least one system cooling water passage is provided with a rib between the cylinders, the rib facing the cooling water flow flowing from each cylinder side through the cooling water passage, and the cooling water passage. A communication passage that communicates the passage with another cooling water passage is provided on each cylinder side in close proximity to the rib.

The invention according to claim 2 is characterized in that, in the invention according to claim 1, the rib is installed so as to face a cooling water flow flowing between the ports of the respective cylinders.

According to a third aspect of the present invention, in the first or second aspect of the invention, the ribs are installed across the head bolt through hole walls provided corresponding to the positions between the cylinders. It is characterized by

A fourth aspect of the invention is characterized in that, in the third aspect of the invention, the ribs are installed on the wall of the head bolt through hole without a gap.

The invention according to claim 5 is the same as claim 1.
In any of the above aspects, the at least two systems of cooling water passages include a lower cooling water passage formed on the lower wall side of the cylinder head and an upper cooling water passage formed on the upper wall side of the cylinder head. A passage is provided, and the rib is installed between the cylinders of the lower cooling water passage so as to connect the lower wall and the upper wall.

Further, the invention according to claim 6 is the same as claim 5.
In the invention described in (1), the rib has a surface facing the cooling water flow formed as a concave surface in a transverse direction of the water flow.

The invention according to claim 7 is the invention according to claim 5 or 6, wherein the communication passage is provided with a width shorter than the width of the rib in a direction traversing the cooling water flow. It is characterized by

The invention according to claim 8 is further defined by claim 1
The invention according to any one of claims 7 to 7 is characterized in that the communication passages provided near the ribs and on the respective cylinder sides are provided so that the effective communication cross-sectional areas are different from each other.

[0017]

That is, according to the invention of claim 1, ribs are provided which face the cooling water flow coming from each cylinder side,
Since the communication passages are provided close to the ribs on the respective cylinder sides, that is, on both sides of the ribs, the cooling water flows flowing from the respective cylinder sides hit the ribs without interfering with each other. , Can be guided to another cooling water passage through a communication passage provided near the rib. Therefore, it is possible to prevent the water flow from wrapping around to the opposite side of the ribs as much as possible and prevent the cooling water flow from stagnation. As a result, even in the flow of cooling water that can effectively cool each cylinder (as a result, the flow of cooling water to the adjacent cylinder becomes a counterflow), the cooling water smoothly flows through the cooling water passage, The cooling efficiency of the cylinder head is further improved.

According to the invention of claim 2, the rib is
Since it is installed so as to face the cooling water flow flowing between the ports of each cylinder, the stagnation does not occur in the cooling water flow flowing between the ports, and the port wall, especially the wall of the exhaust port that becomes hot Cooling can be promoted.

According to the third aspect of the present invention, since the ribs are installed between the walls of the head bolt through holes, it is possible to effectively prevent the cooling water flow from flowing around the ribs and flowing into the adjacent cylinder side, and the stagnation occurs. The occurrence of can be prevented more reliably.

According to the fourth aspect of the present invention, since the ribs are installed without gaps between the head bolt through hole walls, it is possible to reliably prevent the cooling water flow from flowing around the ribs.

According to the fifth aspect of the present invention, it is possible to construct a cylinder head having a cooling water passage structure of two upper and lower stages. In addition, since it is possible to reliably prevent stagnation in the lower cooling water passage, it is possible to configure a cylinder head that can efficiently cool the high temperature side.

According to the sixth aspect of the present invention, since the surface of the rib facing the cooling water flow is formed into a concave surface, it is possible to prevent the water flow from wrapping around both sides of the rib and to flow toward the rib. Without disturbing the incoming cooling water flow, it can be guided toward the center of the rib and guided to the upper communication path, and a steady cooling water flow can be formed.

According to the seventh aspect of the present invention, since the communication passage is provided with a width shorter than the width of the rib, the cooling water flow that hits the rib is guided to the communication passage side without exhaustion, and stagnation is prevented. be able to.

According to the invention described in claim 8, since the effective communication cross-sectional areas of the communication passages respectively provided on the respective cylinder sides are different from each other, water flows having different momentum (for example, cooling water passages). The water flow velocity can be adjusted by changing the water flow resistance to the upstream side water flow and the downstream side water flow, which are considered as a whole, and the cooling efficiency can be improved.

[0025]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the accompanying drawings. Cylinder head 20 of the embodiment
Are configured as shown in FIGS. A diesel engine is configured by installing a plurality of cylinders so as to cover an upper portion of a cylinder block (not shown) provided in parallel. FIG. 1 is a partial vertical cross-sectional view of a cylinder head 20 at an intermediate position between adjacent cylinders, which is shown along the line I-I in FIG. 2 is a partial cross-sectional view of the cylinder head 20 and is shown along the line II-II in FIG. Although a diesel engine will be described as the internal combustion engine in this embodiment, the present invention is of course applicable to other internal combustion engines such as a gasoline engine.

The cylinder head 20 has an upper wall 21 and a lower wall 22, and an upper cooling water passage 24 is formed between the upper wall 21 and the lower wall 22 with a partition wall 23 interposed therebetween.
The lower cooling water passage 25 is formed on the lower side, and the upper and lower two stages (2
System) of the cooling water passage structure.

As shown in FIG. 2, head bolt through holes 3 are formed on both sides of the cylinder head 20 so as to penetrate the cylinder head 20 in correspondence with the intermediate positions of the adjacent cylinders.
1, 31 are provided. Further, two intake ports 32, 33 and two exhaust ports 34, 35 are provided at radial positions with respect to the center of the cylinder in correspondence with the position of each cylinder. A mounting portion 36 of the fuel injection nozzle is provided corresponding to the above.

A rib 41 is provided so as to cross the upper cooling water passage 24 and the lower cooling water passage 25 at a position between the cylinders where the head bolt through holes 31, 31 are provided. The upper end of the rib 41 is continuous with the upper wall 21, and the lower end of the rib 41 is continuous with the lower wall 22. The deformation stress of the lower wall 22 is transmitted to the upper wall 21 through the rib 41 so as to be opposed to each other. The rigidity of the wall 22 is enhanced.

The ribs 41 have the head bolt through holes 3 on both sides.
Installed at an intermediate position on the line connecting 1 and 31, corresponding to the cylinder 42 on one side (left side) and the gap 42 between the intake port 33 and the exhaust port 35, and corresponding to the cylinder on the other side (right side) The gap 43 between the intake port 32 and the exhaust port 34 is provided so as to face each other, and the width is set wider than the gaps 42 and 43.

In addition to the ribs 41 thus installed, communication passages 51a and 51b are formed in the partition wall 23 at positions on both sides of the ribs 41, and the upper cooling water passage 24 and the lower cooling water passage 25 are formed. Communicate with each other through the communication passage 51. The communication passages 51 a and 51 b are formed in a long and narrow elongated hole shape along the width direction of the rib 41, and the length thereof is the rib 41.
The width is shorter than the width. The effective communication cross-sectional area of the communication passage 51b is larger than that of the communication passage 51a.

In the cooling water passage structure of the embodiment configured as described above, the cooling water in each cylinder in the lower cooling water passage 25 has the gap 4 as indicated by arrows A1 and A2.
2 and 43 are made to flow toward the rib 41, the cooling water flow passing through the gaps 42 and 43 between the ports becomes
After hitting 1, the communicating passages 51a and 51b formed at the upper portions on both sides of the rib 41 are passed through, and the upper cooling water passage 24 is kept as it is.
It can be ideally led to as indicated by arrows B1 and B2. Considering the entire cylinder head, the left side in FIG. 2 is the upstream side, and the right side is the downstream side. The flow of cooling water A1, A
Although there is a difference in momentum between the two, in the above configuration, the cooling water flows flowing between the ports of the respective cylinders are guided to the upper cooling water passage 24 without interfering with each other, and as a result, the cooling water flows flowing between the ports. You can prevent stagnation. Therefore, it is possible to efficiently cool the lower wall 22 side of the cylinder head 20, which has a relatively high temperature, and also efficiently cool between the ports and around the fuel injection nozzle.

As in the embodiment, when the length of the communication passages 51a and 51b is made shorter than the length of the ribs 41 in the width direction, the cooling water flow that hits the ribs 41 and is guided to the communication passages 51a and 51b diverges. Instead, they can be concentrated on the communication passages 51a and 51b. Therefore, it is possible to reduce the flow passing around the outside of the rib 41 and flowing around to the adjacent cylinder side, and it is possible to substantially completely eliminate the mutual interference of the cooling water flows of the respective cylinders. As for the flow of the cooling water flows A1 and A2, the flow of A1 toward the downstream side is stronger, and the flow of A2 toward the upstream side is weaker.
The communication passages 5 are made different by differentiating the effective communication cross-sectional areas of 1a and 51b.
Since 1b is made larger, the cooling water flow A2 becomes easier to flow, and the difference in momentum between the two can be reduced. This action is obtained because the water streams flowing through the communication passages 51a and 51b are independent of each other.

Although the ribs 41 are provided continuously to the upper wall 21 and the lower wall 22, respectively, the rigidity of the lower wall 22 can be strengthened by other means, or the lower wall 22 itself. When the rib 44 has sufficient rigidity, the rib 44 may have a height substantially equal to the height at which the partition wall 23 is installed, as shown in FIG. Even in this case, the cooling water flow that flows between the ports in each cylinder as indicated by arrows A1 and A2 can strike the ribs 44 to eliminate mutual interference, as in the case described above. Then, the cooling water flow hitting the ribs 44 is directly passed through the communication passages 51a and 51b as indicated by arrows B1 and B2, and the upper cooling water passage 24
To prevent stagnation in the cooling water flow.

Further, as shown in FIG. 4, the ribs 45 may be installed without gaps between the hole walls of the head bolt through holes 31, 31 which are installed corresponding to the positions between the cylinders. With this configuration, the flow of the cooling water that flows around the rib 45 and flows into the adjacent cylinder side can be reliably prevented, and the cause of the stagnation can be eliminated.

Further, ribs 46 as shown in FIG. 5 may be used. The rib 46 has a concave surface 47 facing the cooling water flow flowing from each cylinder. In the case of the rib 46, the cooling water flow flowing toward the rib 46 is directed toward the center of the rib 46, that is,
It is possible to guide the concave surface 47 in the most concave direction, it is possible to further suppress the cooling water flow from flowing to both ends of the rib 46, and it is possible to prevent turbulent flow from occurring in the portion where the water flow hits the rib 46. Then, the cooling water flow can be reliably guided to the communication passage 51. In this way, it is possible to form a steady and stable flow of cooling water.

The embodiment of the cooling water passage structure having the two-stage structure of the upper cooling water passage 24 and the lower cooling water passage 25 has been described above, but the present invention is not limited to this, and still another embodiment. It may have a cooling water passage. The cylinder head 2 is not limited to these configurations.
The present invention can be equally applied to the case where a plurality of systems of cooling water passages are formed in 0. That is,
When there is a cooling water flow that interferes with each other in at least one system cooling water passage, a rib and a communication passage in the vicinity thereof may be provided so as to be guided to another cooling water passage.

[0037]

As described above, according to the cooling water passage structure of the cylinder head of the present invention, of the cooling water passages,
At least one system cooling water passage is provided with ribs between the cylinders, the ribs facing the cooling water flow flowing from each cylinder side through the cooling water passage, and the cooling water passage and other cooling water. Since the communication passages for communicating the passages are provided close to the ribs on the respective cylinder sides, it is possible to prevent the cooling water flows of the adjacent cylinders from interfering with each other and prevent stagnation. Excellent cylinder head cooling efficiency can be obtained.

[Brief description of drawings]

FIG. 1 is a vertical cross-sectional view showing a part of a cylinder head of an embodiment of the present invention at a position between cylinders, which is taken along a line I-I in FIG.

FIG. 2 is likewise a cross-sectional view showing a part of the embodiment, which is taken along line II-II in FIG.

FIG. 3 is a partial vertical sectional view showing another embodiment in which the rib of the present invention is changed.

FIG. 4 is a partial cross-sectional view of the same.

FIG. 5 is a partial cross-sectional view of another embodiment in which the rib of the present invention is another rib.

6 is a partial vertical cross-sectional view showing a conventional cylinder head, which is taken along line VI-VI in FIG. 7.

7 is a partial cross-sectional view showing a conventional cylinder head, which is taken along the line VII-VII in FIG.

FIG. 8 is a partial vertical cross-sectional view showing a conventional cylinder head, which is taken along the line VIII-VIII in FIG.

9 is a cross-sectional view taken along the line IX-IX in FIG. 6 similar to FIG. 7, and is a diagram for explaining the occurrence of stagnation.

FIG. 10 is a partial vertical cross-sectional view of another conventional cylinder head at a position between cylinders, which is taken along line XX in FIG.

FIG. 11 is a partial transverse cross-sectional view showing another cylinder head of the same, taken along the line XI-XI in FIG.

[Explanation of symbols]

20 cylinder head 21 Upper wall 22 Lower wall 23 partition walls 24 Upper cooling water passage 25 Lower cooling water passage 31 Head bolt through hole 32 intake ports 33 Intake port 34 Exhaust port 35 exhaust port 36 Attachment 41 rib 42 Gap 43 Gap 44 ribs 45 ribs 46 ribs 47 concave 51a communication passage 51b communication passage

Claims (8)

[Claims] 1. A cooling water passage structure for a cylinder head, comprising: a cylinder block formed of a plurality of cylinders arranged in parallel, wherein at least two systems of cooling water passages are formed therein. Among the cooling water passages, at least one system cooling water passage is provided with a rib between the cylinders, the rib facing the cooling water flow flowing from each cylinder side through the cooling water passage, and the cooling water passage. A cooling water passage structure for a cylinder head, characterized in that communication passages for communicating the passage with other cooling water passages are provided on the respective cylinder sides in close proximity to the ribs. 2. The cooling water passage structure for a cylinder head according to claim 1, wherein the rib is installed so as to face a cooling water flow flowing between the ports of each cylinder. 3. The cooling water passage of the cylinder head according to claim 1, wherein the rib is provided between head bolt through hole walls provided so as to correspond to positions between the cylinders. Construction. 4. The cooling water passage structure for a cylinder head according to claim 3, wherein the ribs are provided on the wall of the head bolt through hole without any gap. 5. The cooling water passage of at least two systems,
A lower cooling water passage formed on the lower wall side of the cylinder head and an upper cooling water passage formed on the upper wall side of the cylinder head, wherein the rib is between the cylinders of the lower cooling water passage,
The cooling water passage structure for a cylinder head according to claim 1, wherein the cooling water passage structure is installed so as to connect the lower wall and the upper wall. 6. The rib has a surface facing the cooling water flow,
The cooling water passage structure for a cylinder head according to claim 5, wherein the cooling water passage structure is formed in a concave surface in a transverse direction of the water flow. 7. The cooling water passage structure for a cylinder head according to claim 5, wherein the communication passage is provided with a width shorter than a width of the rib in the transverse direction of the cooling water flow. 8. The communication passages provided on the respective cylinder sides in the vicinity of the ribs are provided so that the effective communication cross-sectional areas are different from each other. A cooling water passage structure for a cylinder head according to any one of the above.