JPH05321662A - Cooling device of internal combustion engine - Google Patents

Abstract

PURPOSE:To improve the antiknock property by positively cooling the suction port side while securing the combustibility. CONSTITUTION:A cooling water introducing part 9 is provided to a suction port 6 side of a in-block cooling water passage 8, and a cooling water discharging part 11 is provided to an exhaust port 7 side respectively. A cooling water introducing part 13 which is communicated with a block side cooling water discharging part 11 is provided to the exhaust port 7 side of an in-head cooling water passage 12, and a cooling water discharging part 15 is provided to the suction port 6 side. A first cooling route is formed so that the cooling water may enter the in-head cooling water passage 12 and be discharged from the suction port 6 side after the water introduced in the in-block cooling water passage 8 flows from the suction port 6 side to the exhaust port 7 side. A partitioning wall 19 is provided to the in-head cooling water passage 12 along the wall surface of a combustion chamber 5, and at the same time, a cooling water pipe 20 is opened inside of the partitioning wall 19, and a second cooling route is formed so that the combustion chamber wall on the suction port 6 may positively be cooled.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cooling device for an internal combustion engine for vehicles.

[0002]

2. Description of the Related Art In an internal combustion engine, a cylinder block and a cylinder head are kept at a high temperature as a whole to improve combustibility, while locally enhancing cooling efficiency to prevent knocking or to improve charging efficiency. There is a need. Therefore, conventionally, for example, actual development Sho 62-156
As described in Japanese Patent No. 126, the cooling water is introduced from the cooling water inlet provided on the intake port side into the cooling water passage in the cylinder head, flows around the plug and flows to the exhaust port side, and at the exhaust port side, The two branches into two flows, one of which flows around the exhaust port to the outside from the head side cooling water outlet, and the other of which flows into the cylinder block cooling water passage through the communication passage, and the cylinder block cooling water passage A configuration is proposed in which the flow is directed toward the intake port side in a direction orthogonal to the cylinder arrangement direction.

[0003]

By the way, as one direction for increasing the output of the internal combustion engine, the stroke is increased with respect to the cylinder bore diameter, and supercharging is performed to increase the air filling amount. However, in the case of an internal combustion engine that achieves high output in this way, there is a problem that knocking is more likely to occur due to the large air charge amount. Therefore, in order to prevent knocking, it is necessary to actively cool the intake port side where heat points are likely to occur, particularly the combustion port wall of the intake port side of the cylinder head. However, in the device disclosed in the above publication, for example, Since low-temperature cooling water flows through the entire cooling water passage in the cylinder head, if the cooling efficiency on the intake port side is attempted to be increased, the overall temperature will drop and the combustibility will deteriorate.

The present invention has been made in view of the above problems, and provides a cooling device for an internal combustion engine capable of improving the knock resistance by positively cooling the intake port side while ensuring combustibility. The purpose is to get.

[0005]

A cooling device for an internal combustion engine according to the present invention is provided with a cooling water passage around a bore of a cylinder block, a block side cooling water introducing portion is provided at a portion on the intake port side thereof, and an exhaust gas is also provided. Block-side cooling water outlets are provided at the port-side portions so that the block-side cooling water outlets communicate with the cooling-water passages inside the cylinder head. A side cooling water outlet is provided, and the block side cooling water inlet, the cooling water passage around the bore, the block side cooling water outlet, the cooling water passage in the cylinder head, and the head side cooling water outlet lead the first cooling path. And a second cooling path for locally introducing cooling water toward the intake port side combustion chamber wall is provided in the cylinder head.

Further, in order to more efficiently cool the wall portion of the combustion chamber on the intake port side of the cylinder head, in the above structure, the flow velocity of the cooling water introduced into the second cooling path is the cooling water introduced into the first cooling path. It is possible to provide a means for increasing the flow velocity of the cooling water introduced into the second cooling passage, and a means for lowering the set temperature of the cooling water introduced into the second cooling passage below the set temperature of the cooling water introduced into the first cooling passage. .. that time,
The means for increasing the flow velocity of the cooling water introduced into the second cooling path shall be a series arrangement of the first water pump installed in the first cooling path and the second water pump installed in the second cooling path. As a means for lowering the set temperature of the cooling water introduced into the first cooling path, the heater section of the vehicle interior temperature control system can be used.

In order to cool the intake port side of the cylinder block more efficiently, it is necessary to direct the block side cooling water introducing portion opening to the cooling water passage around the bore toward the top deck portion of the cylinder block. Good.

Further, in order to cool each cylinder efficiently, it is preferable that the cooling water passage around the bore be independent for each cylinder.

Further, in order to make the heat distribution in the bore of the cylinder block uniform and prevent thermal deformation, and in order to cool the intake port side more efficiently, the cooling water passage around the bore is provided in a portion near the cylinder head. The capacity should be larger than the others.

Further, in the case of having a plurality of intake ports, in order to efficiently cool the combustion chamber wall between the intake ports where the heat point is most likely to occur, the second cooling path has the combustion chamber between the plurality of intake ports. The cooling water may be formed to flow along the wall.

[0011]

According to the structure of the present invention, the cooling water flowing through the first cooling passage enters the cooling water passage around the bore from the block side cooling water introduction portion provided at the intake port side portion of the cylinder block, and the cooling water flows around the bore. While flowing into the cooling water passage in the cylinder head from the block side cooling water outlet on the exhaust port side. Then, the cooling water flows from the exhaust port side to the intake port side while cooling the combustion chamber wall in the cooling water passage in the cylinder head, and is discharged from the head side cooling water lead-out portion provided on the intake port side. Separately from this, the cooling water is locally introduced from the second cooling path provided in the cylinder head toward the intake port side combustion chamber wall, and the intake port side combustion is performed by the cooling water in the second cooling path. The chamber wall is actively cooled.

The flow velocity of the cooling water introduced into the second cooling path is the first due to the series arrangement of the first water pump installed in the first cooling path and the second water pump installed in the second cooling path. By making the flow velocity of the cooling water introduced into the cooling passage larger than that of the cooling water, the set temperature of the cooling water introduced into the second cooling passage is set to the first cooling by the means utilizing the heater part of the vehicle interior temperature control system. By making the temperature of the cooling water introduced into the passage lower than the set temperature, the intake port side combustion chamber wall portion of the cylinder head is cooled more efficiently.

Further, since the block side cooling water introducing portion opening to the cooling water passage around the bore is directed toward the top deck portion of the cylinder block, the intake port side of the cylinder block is cooled more efficiently.

Further, since the cooling water passage around the bore is independent for each cylinder, each cylinder is efficiently cooled without unevenness, and the capacity around the bore is close to the cylinder head. By making it large, the heat distribution in the longitudinal direction of the cylinder block is made uniform, and thermal deformation is prevented.

Further, in the internal combustion engine having a plurality of intake ports, the second cooling path is formed so as to allow the cooling water to flow along the combustion chamber wall between the plurality of intake ports, so that the most heat point occurs. The combustion chamber wall between the intake ports is cooled efficiently.

[0016]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a partial sectional view of an internal combustion engine showing an embodiment of the present invention, FIG. 2 is a sectional view taken along the line AA of FIG. 1, and FIG. 3 is a partial plan view of the internal combustion engine seen from above a cylinder head. is there.
In this embodiment, the internal combustion engine 1 has three in-line cylinders,
A dry liner 3 is fitted to the inner circumference of the bore 2a of each cylinder in the cylinder block 2, and a cylinder head 4 is mounted on the top of the cylinder block 2. Then, a piston (not shown) slides along the liner 3 in the cylinder block 2. A combustion chamber 5 for each cylinder is formed in the cylinder head 4, and two intake ports 6 and two exhaust ports 7 are provided so as to open in each combustion chamber 5.

Each cylinder block 2 has a bore portion 2
Independent block cooling water passages 8 are provided around a. The in-block cooling water passage 8 is formed in an annular shape so as to surround the upper half of the bore portion 2a, and the upper half thereof has a large capacity with a cross section enlarged relative to the lower half. Then, on the intake port 6 side of the in-block cooling water passage 8, a block-side cooling water introducing portion that is directed toward the top deck portion 2b of the cylinder block 2 at approximately the vertical center of the in-block cooling water passage 8. 9
Further, on the exhaust port 7 side of the in-block cooling water passage 8, a block-side cooling water lead-out portion 11 is provided for each cylinder so as to open to the head mating surface 10.

Further, in the cylinder head 4, an in-head cooling water passage 12 is formed along the wall surface of the combustion chamber 5 of each cylinder. A head-side cooling water introducing portion 13 is provided at a position communicating with each block-side cooling water outlet portion 11 on the exhaust port 7 side of the in-head cooling water passage 12, and a block mating surface 14 is provided on the intake port 6 side. A head-side cooling water lead-out portion 15 is provided at a position that opens at. The head mating surface 10 of the cylinder block 2 is provided with a cooling water discharge part 16 at a position communicating with each head side cooling water lead-out part 15.

In each head cooling water passage 12 of the cylinder head 4, a passage portion which rises between the two intake ports 6 of each cylinder from the block mating surface and goes to the head side cooling water outlet 15 side. A partition wall 19 for partitioning a passage portion 18 along the wall surface of the combustion chamber 5 from 17 is provided, and the lower end of the passage portion 18 inside the partition wall 19 is opened to the block mating surface 14. Then, a cooling water pipe 20 is horizontally inserted into the cylinder head 4 at a position close to the block mating surface 14 from the intake port 6 side, and the cooling water pipe 20 penetrates the partition wall 19 and the tip thereof is the partition wall. It is opened inside the wall 19. Further, the cylinder block 2 is provided with a communication passage 21 which opens to the head mating surface 10 and communicates with the lower end opening of the passage portion 18 inside the partition wall 19.

The block side cooling water introducing portion 9 has a first
Cooling water is supplied from the water pump 32 through the cooling water introducing passage 22. In addition, the cooling water pipe 20 has
Cooling water is supplied from a second water pump 33 arranged in series with the first water pump 32. The cooling water flowing through the second water pump 33 passes through the heater section 34 of the vehicle interior temperature control system on the way. In addition, in FIG.
Is a radiator, and 36 is a thermosensor.

Then, the cooling water supplied to the block side cooling water introducing portion 9 enters the block cooling water passage 8 from the block side cooling water introducing portion 9 and cools the periphery of the bore portion 2a while the exhaust port 7 is being cooled. And flows into the in-head cooling water passage 12 from the block side cooling water outlet 11. Then, the cooling water flows through the in-head cooling water passage 12 toward the intake port 6 side while cooling the combustion chamber wall, and from the head side cooling water outlet 15 provided on the intake port 6 side to the cooling water discharger 16
Is discharged to. Further, the cooling water supplied to the cooling water pipe 20 is jetted to the passage portion 18 inside the partition wall.
Then, the cooling water ejected from the cooling water pipe locally cools the combustion chamber wall on the intake port 6 side. The cooling water introduced into the cooling water pipe 20 has a high flow velocity by being pressurized by the two water pumps 32 and 33 arranged in series, and has a low temperature due to heat exchange by the heater portion 34. Therefore, efficient cooling of the intake port 6 side is thereby achieved. Also,
The cooling water introduced from the block-side cooling water introducing portion 9 flows around the bore portion 2a from the intake port 6 side to the exhaust port 7 side, so that the intake port 6 side is further cooled, and especially the introduction direction is the top deck portion. By being directed to the 2b side, the high temperature side of the bore portion 2a is efficiently cooled and the heat distribution is made uniform.

Next, in connection with the above embodiment, another example of the structure for locally cooling the combustion chamber head wall will be described with reference to FIGS.
Explained by.

FIG. 4 and FIG. 5 (showing the BB cross section of FIG. 4) are an example thereof. In this case, the inside is divided into a large number of horizontally aligned openings 23 and the tip is cut obliquely. The local cooling pipe 24 is horizontally inserted into the cylinder head 4 from the intake port 6 side at a position close to the block mating surface 14, and its upper end is fixed so as to form a local cooling jacket 25 below.

6 and 7 (showing the C-C cross section in FIG. 6) are other examples, and in this case, in the portion from the intake port 6 side inside the cylinder head 4 to the gas end zone 26. A local cooling jacket 27 is formed, and a flat local cooling pipe 29, which is divided into a large number of horizontally arranged openings 28, is inserted into the local cooling jacket 27 so as to open at the gas end zone 26 side of the local cooling jacket 27. There is.

Further, FIGS. 8 and 9 (showing the D-D cross section of FIG. 8) are other examples. In this case, the cylinder head 4 is exposed to the inner surface side and surrounds the gas end zone 26. As described above, the local cooling ring 30 made of Cu or the like is arranged, and the Ag coating layer 31 is provided on the wall surface on the gas end zone 26 side including the local cooling ring 30 by plating or thermal spraying.

[0027]

Since the present invention is constructed as described above, it is possible to improve the knock resistance by positively cooling the intake port side while ensuring the combustibility.

[Brief description of drawings]

FIG. 1 is a partial sectional view of an internal combustion engine showing an embodiment of the present invention.

FIG. 2 is a sectional view taken along line AA of FIG.

FIG. 3 is a partial plan view of an internal combustion engine according to an embodiment of the present invention as seen from above a cylinder head.

FIG. 4 is a structural diagram showing a structural example for locally cooling the combustion chamber head wall in relation to the above-described embodiment.

5 is a sectional view taken along line BB of FIG.

FIG. 6 is a structural diagram showing another structural example for locally cooling the combustion chamber head wall in relation to the above embodiment.

7 is a sectional view taken along line CC of FIG.

FIG. 8 is a structural diagram showing still another structural example for locally cooling the combustion chamber head wall in relation to the above embodiment.

9 is a sectional view taken along line DD of FIG.

[Explanation of symbols]

 1 Internal Combustion Engine 2 Cylinder Block 4 Cylinder Head 5 Combustion Chamber 6 Intake Port 7 Exhaust Port 8 Cooling Water Passage in Block 9 Block Side Cooling Water Introducing Section 11 Block Side Cooling Water Deriving Section 12 Head Cooling Water Passage 13 Head Side Cooling Water Introduction Part 15 Head side cooling water lead-out part 19 Partition wall 20 Cooling water pipe 32 First water pump 33 Second water pump 34 Heater part

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁵ Identification code Office reference number FI Technical display location F02F 1/36 C 8503-3G 1/40 B 8503-3G

Claims (9)

[Claims] 1. A cooling water passage is provided around a bore of a cylinder block, a block side cooling water introducing portion is provided at a portion on the intake port side thereof, and a block side cooling water outlet portion is provided at a portion on the exhaust port side thereof. , The block side cooling water outlet is communicated with a cooling water passage in the cylinder head, and a head side cooling water outlet is provided in a portion of the cylinder head on the intake port side of the cooling water passage for cooling the block side. A first cooling path is formed by the water introducing portion, the cooling water passage around the bore, the block side cooling water outlet portion, the cooling water passage in the cylinder head and the head side cooling water outlet portion, and an intake port in the cylinder head. A cooling device for an internal combustion engine, comprising a second cooling path for locally introducing cooling water toward a side combustion chamber wall. 2. The cooling device for an internal combustion engine according to claim 1, further comprising means for increasing the flow rate of the cooling water introduced into the second cooling path to be higher than the flow rate of the cooling water introduced into the first cooling path. 3. The cooling device for an internal combustion engine according to claim 2, wherein the means is a series arrangement of a first water pump installed in the first cooling path and a second water pump installed in the second cooling path. .. 4. The cooling device for an internal combustion engine according to claim 1, further comprising means for lowering the set temperature of the cooling water introduced into the second cooling path below the set temperature of the cooling water introduced into the first cooling path. 5. The cooling device for an internal combustion engine according to claim 4, wherein the means is a heater section of a vehicle interior temperature control system. 6. The cooling device for an internal combustion engine according to claim 1, wherein the block-side cooling water introduction portion opening to the cooling water passage around the bore is oriented toward the top deck portion of the cylinder block. 7. The cooling device for an internal combustion engine according to claim 1, wherein the cooling water passage around the bore is independent for each cylinder. 8. The cooling device for an internal combustion engine according to claim 1, 6 or 7, wherein the cooling water passage around the bore has a larger capacity in a portion close to the cylinder head than the other portions. 9. The second cooling passage is formed so that cooling water flows along the combustion chamber wall between the plurality of intake ports.
Or a cooling device for an internal combustion engine according to item 4.