JP3533706B2 - Cooling device for internal combustion engine - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an internal combustion engine capable of sending cooling water toward a portion of a cylinder head, even if a drill hole serving as a cooling water passage cannot be formed due to the layout of the valve. The present invention relates to an engine cooling device.

[0002]

2. Description of the Related Art Conventionally, cooling around a cylinder head of an internal combustion engine is carried out by circulating cooling water through a water jacket of the cylinder head by a water pump. However, the valve of the cylinder head 1 shown in FIGS. Between the two and around the fuel injection nozzle 3, since the heat load is particularly high, a cooling drill hole 4 is opened in the cylinder head 1 and cooling water is circulated there to cool the cylinder.

When forming the cooling drill hole 4 as described above, there is no problem if the valve 2 is arranged at a right angle to the cylinder head. However, due to the valve layout, as shown in FIG. When the arrangement direction of the valve 2 is twisted with respect to the cylinder head, it is often impossible to make the cooling drill hole 4. In that case,
Although the water jacket 5 is formed in the vicinity of the valve 2 and the fuel injection nozzle 3 by casting, the cooling water cannot be forcibly filled in the space between the valves 2 and the valve 2
The flow of the cooling water during that period becomes slow, and it is difficult to perform positive cooling by circulating the cooling water.

[0004]

Therefore, as shown in FIG. 9, a bent hole 6 is formed in the bent pipe 6 for guiding the cooling water at a position slightly separated from the valve 2 and the fuel injection nozzle 3.
As shown in FIG. 10, the bent pipe 6 is used to supply cooling water between the valves 2 and toward the fuel injection nozzle 3, or as shown in FIG. A drill hole 7 is opened in the head 1, and as shown in FIGS. 12 and 13, a sealing cup 10 having a cutout hole 9 is press-fitted into the cutout hole 7 so that the cooling water flows in the direction of the cutout hole 9. Instead, it is sent to a portion with a high heat load such as between the valves 2.

However, in the means for press-fitting the bent pipe 6 or the sealing cup 10, it is necessary to manufacture the bent pipe 6 or the sealing cup 10 separately from the cylinder head 1, and the work of assembling them by a method such as press-fitting is required. Since it is necessary, there is a problem that the number of steps increases and the cost increases. In view of the above problems, the present invention provides a cooling device for an internal combustion engine capable of positively supplying cooling water to a high heat load portion of a cylinder head without increasing man-hours in conventional equipment. The purpose is to do.

[0006]

The cooling device for an internal combustion engine according to the present invention for achieving the above object is formed integrally with a cylinder head having a boss projecting from a wall surface of the cylinder head into a water jacket. A cooling device for an internal combustion engine, wherein a drill hole penetrating the wall surface and notching a part of a boss is formed so as to communicate with a water jacket from a cooling water passage, and the top of the boss interferes with the drill hole. The contour of the drill hole and the contour of the boss intersect, and the opening formed in the boss by the drill hole is oriented so as to open toward the portion of the cylinder head where the heat load is high.

Further, the boss is preferably formed on a wall surface of the cylinder head facing the water jacket in a portion facing the cylinder block through at least a gasket, and the openings are formed at least between valves of the cylinder head and fuel injection. It is preferable to orient so as to open toward the nozzle.

[0008]

[Operation] The present invention has the above-described structure, and a perforation hole is opened from the outside on the wall surface of the portion where the boss is formed, and the contour of the perforation hole and the contour of the boss intersect in a plan view. However, a part of the drill hole is removed from the position of the boss to form an opening, and the top of the boss is left so as to interfere with the drill hole in a plan view. When the water passes through the drill hole and exits the opening, the direction of the outflow is changed, and the water flows from the opening toward the high heat load portion of the cylinder head. Therefore, the cooling can be performed efficiently.

Further, since it is no longer necessary to use a bent pipe or a sealing cup provided with a cutout hole in order to change the flow of cooling water in an arbitrary direction as described above, those parts are manufactured. There is no need or need for assembling, and the conventional equipment can be used as it is and can be easily implemented at low cost.

[0010]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a cooling device for an internal combustion engine according to the present invention will be described below with reference to the drawings. In the present embodiment, as shown in FIG. 1, the layout of the valves 11 is twisted with respect to the cylinder heads 12, and when the cooling drill holes cannot be formed in the cylinder heads 12 between the valves 11, this valve 11 A cooling water guide member 14 having an opening 13 is provided toward the side.

When the cooling water guide member 14 is formed, as shown in FIG. 2, the cooling water outflow side (cooling water passage) 15 is formed.
A boss 18 projecting toward the inflow side 16 is provided on the wall surface 17 of the cylinder head 12 that separates the inflow side (water jacket) 16 from the outflow side 15 toward the back surface of the boss 18. A drill hole 20 is opened at 19. At this time,
As shown in, the center line 20C of the drill hole 20 is offset with respect to the center line 18C of the boss 18, and the drill hole has a diameter smaller than the diameter of the boss 18 and does not penetrate the top 18a of the boss 18. 20. Note that the reference numeral 21 indicates a gasket, and the reference numeral 22 indicates a cylinder block.

Further, the offset amount L is such that a part of the drill hole 20 is disengaged from the boss 18 to the extent that it is opened in the direction in which the cooling water should flow out. This is because when the diameter of the drill hole 20 is sufficiently smaller than the diameter of the boss 18 and the offset amount L is also small, the opening 13 is not formed on the side surface of the boss 18 and the outflow direction of the cooling water is controlled. This is because the purpose of doing is not achieved.

Further, when the offset amount L is too large, most of the openings 13 are opened to the wall surface 17 of the cylinder head 12, and the flow direction of the cooling water cannot be changed to an appropriate direction. Make sure that the center line 20C of the drill hole 20 does not deviate from the contour of the boss 18. Also, drill holes 20
If it is too long, it will penetrate the top 18a of the boss 18 and it will not be possible to change the flow direction of the cooling water to an appropriate direction as described above, so the tip of the drill hole 20 must be greater than the height of the boss 18. Try to lower it.

Within the range satisfying the above conditions,
As shown in FIG. 4, even if the offset amount L is slightly increased, the flow of the cooling water is changed between the valves 11 and the direction of the fuel injection nozzle 23. The boss 18 having the drilled hole 20 is formed between the valves 11 having a high heat load and the opening 13 in the fuel injection nozzle 23.
By arranging toward, even if it is not possible to form a cooling drill hole for circulating the cooling water between the valves 11 due to the relationship of the valve layout, by changing the flow direction of the cooling water in the water jacket 16, Between valves 11 and fuel injection nozzle
It is possible to turn in 23 directions. Further, unlike the conventional case, it is not necessary to press fit a bent pipe or a sealing cup having a notched hole into a drill hole, and it can be performed simply by drilling, so that the cost is low and the number of steps is increased. Can be manufactured without.

[0015]

According to the cooling device for an internal combustion engine of the present invention, a boss projecting from the wall surface of the cylinder head into the water jacket is formed integrally with the cylinder head, and a part of the boss is penetrated through the wall surface. A cooling device for an internal combustion engine, wherein a cutout hole is formed so as to communicate with a water jacket from a cooling water passage, the top of the boss interferes with the hole, and the outline of the hole and the outline of the boss. Intersect, and the opening formed in the boss by the drill hole is oriented so as to open toward the portion of the cylinder head where the heat load is high, so that the flow direction of the cooling water supplied from the cooling water passage can be changed. Instead, it is possible to supply the heat from the opening formed in the boss by the drilled hole toward the portion of the cylinder head where the heat load is high. Even if it is not possible to form a drilled hole for the cooling water between the blanking, it can be cooled efficiently cylinder head.

Further, since it is no longer necessary to press fit the bent pipe and the sealing cup in order to change the flow of the cooling water in any direction as described above, it is necessary to manufacture these parts and also to assemble them. Therefore, the conventional equipment can be used as it is, and it can be easily implemented at low cost.

[Brief description of drawings]

FIG. 1 is a plan view of a cooling device for an internal combustion engine according to an embodiment of the present invention.

FIG. 2 is a cross-sectional view of an essential part of a cooling device for an internal combustion engine shown in FIG. 1 during drilling a boss portion.

FIG. 3 is a cross-sectional view of essential parts of a cooling water guide member of the cooling device for an internal combustion engine shown in FIG.

FIG. 4 is a cross-sectional view of essential parts of another cooling water guide member of the cooling device for the internal combustion engine shown in FIG. 1.

FIG. 5 is a sectional view of a main part of a conventional cooling device for an internal combustion engine.

FIG. 6 is a sectional view of a main part of a conventional cooling device for an internal combustion engine.

FIG. 7 is a sectional view of a main part of a conventional cooling device for an internal combustion engine.

FIG. 8 is a plan view of a main part of a conventional cooling device for an internal combustion engine.

FIG. 9 is a sectional view of a main part of a conventional cooling device for an internal combustion engine.

FIG. 10 is a plan view of a main part of a conventional cooling device for an internal combustion engine.

FIG. 11 is a cross-sectional view of essential parts in the process of manufacturing a conventional cooling device for an internal combustion engine.

FIG. 12 is a cross-sectional view of essential parts in the process of manufacturing a conventional cooling device for an internal combustion engine.

FIG. 13 is a cross-sectional view of a main part of a conventional cooling device for an internal combustion engine.

[Explanation of symbols]

11 Valve 12 Cylinder head 13 Opening 15 Cooling water passage 16 Water jacket 17 Wall surface 18 Boss 18a Top 20 Drill hole 21 Gasket 22 Cylinder block

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Claims (3)

(57) [Claims] 1. A boss projecting from a wall surface of a cylinder head into a water jacket is integrally formed with the cylinder head, and a drill hole penetrating the wall surface to cut out a part of the boss is formed from a cooling water passage. A cooling device for an internal combustion engine formed so as to communicate with the water jacket, wherein the top of the boss interferes with the drill hole, and the contour of the drill hole intersects the contour of the boss, and the drill hole forms a boss on the boss. The cooling device for an internal combustion engine, wherein the opening formed is oriented so as to open toward a portion of the cylinder head where the heat load is high. 2. The internal combustion engine according to claim 1, wherein the wall surface of the cylinder head having the boss is a wall surface facing the water jacket at least at a portion facing the cylinder block through the gasket. Cooling system. 3. The cooling device for an internal combustion engine according to claim 1, wherein the opening formed in the boss is oriented so as to open at least between the valves of the cylinder head.