JP3014874B2 - Cooling device in 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 a cooling device for an internal combustion engine, which aims at improving the cooling performance of a cylinder head.

[0002]

2. Description of the Related Art In a recent internal combustion engine, in order to achieve a high compression ratio by suppressing knocking, a cooling water jacket in a cylinder head is provided with a first cooling water jacket extending in a direction of a cylinder row on an intake port side. The exhaust port side is divided into a second cooling water jacket extending in the direction of the cylinder row, and cooling water from a radiator is first introduced into one end of the first cooling water jacket. From the other end of the cooling water pump into the cooling water jacket in the cylinder block, and then from the cooling water jacket in the cylinder block to the second cooling water jacket in the cylinder head and then to the radiator. Yes (actual Kaihei 2
-63052).

[0003] This cooling device is so-called "advanced intake cooling system" because it cools the intake port side of the cylinder head in advance. By the way,
In this type of cooling device using an intake pre-cooling method, an outlet from the first cooling water jacket is opened on one longitudinal side surface of a cylinder head, and this outlet and a cooling water pump attached to a cylinder block are provided. The suction port is connected to the cylinder block and the cylinder head via pipes provided outside the cylinder block and the cylinder head separately.

[0004]

However, as described above,
An outlet of the first cooling water jacket is opened on one side surface in the longitudinal direction of the cylinder head, and between the outlet and a suction port of a cooling water pump attached to the cylinder block,
Connecting to the cylinder block and the cylinder head separately from the pipes arranged outside of the cylinder block and the cylinder head increases the number of parts and the number of assembling steps. Moreover, it is necessary to secure a space for disposing the pipe around the cylinder block and the cylinder head.
There is also a problem that the size and weight of the internal combustion engine are increased.

SUMMARY OF THE INVENTION It is an object of the present invention to solve the above-mentioned conventional problems in a cooling device of an intake pre-cooling system.

[0006]

In order to achieve the above technical object, the present invention provides a cooling water jacket of a cylinder head fastened to an upper surface of a cylinder block, and a first cooling water jacket extending in a direction of a cylinder row on an intake port side. A water jacket,
The exhaust port side is divided into a second cooling water jacket extending in the direction of the cylinder row, and a cooling water inlet from a radiator is provided at one end of the first cooling water jacket, while the other end of the first cooling water jacket is provided. A cooling water pump for sending cooling water from the first cooling water jacket to the cooling water jacket of the cylinder block between the cooling water outlet in the section and the cooling water jacket of the cylinder block; and the second cooling water jacket. A cooling water inlet port and a discharge port, wherein the cooling device has an outlet from a cooling water jacket of a cylinder block to a radiator of the cooling water flowing into the second cooling water jacket. The discharge port of the pump communicates with the cooling water jacket of the cylinder block with respect to the side surface of the cylinder block. While attached to cormorants, the portion exposed from the cylinder block of the cylinder head, and opening the cooling water outlet of the first cooling water jacket,
A suction port of the cooling water pump extends toward a cooling water outlet of the first cooling water jacket, and a peripheral surface of the suction port of the cooling water pump, and a peripheral surface of a cooling water outlet of the first cooling water jacket. When the cylinder head is fastened to the cylinder block or the cooling water pump is attached to the cylinder block, the sealing member is interposed therebetween and pressed against each other to cool the cooling water outlet in the first cooling water jacket and the suction port in the cooling water pump. And join. ".

[0007]

[Work] With this configuration, the suction port of the cooling water pump attached to the cylinder block is simultaneously connected with the fastening of the cylinder head to the cylinder block or the attachment of the cooling water pump to the cylinder block. Use fastening means such as bolts to the cooling water outlet of the first cooling water jacket.
Because it can be directly joined without using
As in the conventional case, the pipe connecting the cooling water outlet of the first cooling water jacket in the cylinder head and the suction port of the cooling water pump can be eliminated.

[0008]

Therefore, according to the present invention, in the cooling device of the pre-cooling type air intake system, the number of parts and the number of steps required for assembling can be reduced, and the cost can be greatly reduced.
In addition, there is an effect that the size and weight of the internal combustion engine can be reduced. According to the second aspect of the present invention, the thermostat valve case accommodating the thermostat valve in the cooling device can be integrated with the cylinder head, and the thermostat valve case accommodating the thermostat valve can be combined with the cylinder head. Since the number of parts and the number of assembling steps can be further reduced as compared with the case where it is attached to the cylinder head, the cost can be further reduced and the size and weight of the internal combustion engine can be further reduced. Has effects that can be achieved.

[0009]

Embodiments of the present invention will be described below with reference to the drawings. In the drawing, reference numeral 1 denotes a cylinder bore axis 3 of each cylinder when viewed from the direction of the crankshaft 2 and a horizontal plane 4.
Shows a slant type multi-cylinder internal combustion engine inclined at an appropriate angle θ with respect to the cylinder block 5.
And a cylinder head 6 fastened by a plurality of head bolts 7 arranged along both sides of the cylinder row with respect to the upper surface of the cylinder block 5. The output side of one end in the longitudinal direction of the internal combustion engine 1 is mounted to be inclined such that the output side is low and the front end side of the other end opposite to the one end is high.

In the cylinder head 6, an intake port 8 with an intake valve 9 for each of the cylinders is formed so as to open to one longitudinal side surface 6a of the cylinder head 6, and each of the cylinders 6 Exhaust valve 1 for
An exhaust port 10 with 1 is formed so as to open to the other longitudinal side surface 6 b of the cylinder head 6. Further, in the cylinder head 6, a portion outside the one head bolt 7 located on the intake port 8 side of the head bolt 7 is provided with a valve mechanism chamber 12 on an upper surface of the cylinder head 6 and a cylinder block 5. A blow-by gas passage 13 also serving as an oil drain for communicating with the inside of the crankcase is formed.

On one longitudinal side surface 6a of the cylinder head 6, an intake port 8 of each cylinder is provided.
Are connected by fastening a integrally formed flange portion 15 with a plurality of bolts 16 between the distal ends of the respective intake pipes 14. The cooling water jacket inside the cylinder head 6 is divided into a first cooling water jacket 18 extending in the direction of the cylinder row on the intake port 8 side by a partition plate 17 formed so as to connect the cylinders to each other, and an exhaust port 10. And a second cooling water jacket 19 extending in the direction of the cylinder row. In this case, the partition plate 17 is provided with a small-diameter air vent hole 20 for allowing air in the second cooling water jacket 19 to escape to the first cooling water jacket 18 from one longitudinal side surface 6 a of the cylinder head 6. It is drilled by drilling with a drill tool. Further, the second cooling water jacket 19 and the cooling water jacket 22 in the cylinder block 5 communicate with each other via a through hole 21 provided outside each cylinder.

A thermostat valve chamber 23 communicating with one end of the first cooling water jacket 18 is recessed at one end on the output side of the two longitudinal ends of the cylinder head 6 and the second cooling water is formed. A cooling water outlet pipe 25 from the jacket 19 to the radiator 24 is provided. The cooling water inlet pipe 26 from the radiator 24 is connected to the thermostat valve chamber 23. In the thermostat valve chamber 23, when the temperature of the cooling water is low, the second cooling water jacket 19 to the first cooling water jacket 18 are connected. When the temperature of the cooling water rises to a predetermined temperature, the bypass passage 27 is closed, while the bypass passage 27 is closed.
Thermostat valve 2 that operates so that all of the cooling water from radiator 24 flows into first cooling water jacket 18.
8 is provided.

Furthermore, a part of the other end on the front end side of the longitudinal end portions of the cylinder head 6 is
Projecting outward from the side of the cylinder block 5
The first cooling water jacket is provided on the lower surface of the projected portion.
A cooling water outlet 29 from the cooling water outlet 18 is opened, and a peripheral surface 29 a of the cooling water outlet 29 is formed flush with the lower surface of the cylinder head 6.

On the other hand, a cooling water pump 30 having a built-in impeller 30a which is rotationally driven by power transmission from the crankshaft 2 is provided on the side of the other end of the front end of the cylinder block 5 in the longitudinal direction. The cooling water pump 30 is attached by fastening with a plurality of bolts 31 so that the discharge port 30b of the cooling water pump 30 communicates with the cooling water jacket 32 of the cylinder block 5.

The suction port 30c of the cooling water pump 30 is extended toward the cooling water outlet 29 of the first cooling water jacket 18 of the cylinder head 6, and the peripheral surface 30c 'of the suction port 30c is 1 Peripheral surface 29 of cooling water outlet 29 in cooling water jacket 18
a at the same time as attaching the cylinder head 6 to the cylinder block 5 with the head bolts 7 and pressing a sealing material such as an O-ring 32 therebetween .
Thus, the suction port 30c and the cooling water outlet 29 are directly connected to each other.

An opening 18a for the first cooling water jacket 18 is formed in a portion of the one longitudinal side surface 6a of the cylinder head 6 corresponding to the blow-by gas passage 13, and the opening 18a is connected to the opening 18a. By closing with a lid 15a formed integrally with the connecting flange portion 15 in each intake pipe line 14, the passage cross-sectional area along the longitudinal direction of the first cooling water jacket 18 is reduced. Is configured not to be reduced at the point.

In this configuration, in a warm-up operation in which the temperature of the cooling water has not risen to the predetermined temperature, the thermostat valve 28 closes the passage from the radiator 24 and opens the bypass passage 27, so that the cylinder block 5
The cooling water in the cooling water jacket 22 at
After flowing out into the second cooling water jacket 19 in the cylinder head 6 through the first cooling water jacket 18, it flows into the first cooling water jacket 18 from the bypass passage 27.
Is carried out into the cooling water jacket 22.

When the temperature of the cooling water rises to a predetermined temperature, the thermostat valve 28 is turned on by the radiator 2.
The cooling water cooled by the radiator 24 first flows into the first cooling water jacket 18 of the cylinder head 6 by operating the bypass passage 27 to close the bypass passage 27 while opening the passage from the cylinder 4. After cooling the portion of the head 6 on the intake port 8 side, the cooling water pump 3
0, the water is fed into the cooling water jacket 22 in the cylinder block 5, and then flows from the cooling water jacket 22 in the cylinder block 5 into the second cooling water jacket 19 in the cylinder head 6 through the through hole 21, and then to the radiator 24. The cycle that leads to it.

As shown in FIG. 5, instead of opening the cooling water outlet 29 in the first cooling water jacket 18 on the lower surface of the cylinder head 6 as in the above embodiment, , The suction port 30c of the cooling water pump 30 is extended toward the cooling water outlet 29 on the side surface of the cylinder head 6, and the peripheral surface 30 of the suction port 30c is opened.
c ′ with respect to the peripheral surface 29 a of the cooling water outlet 29 in the first cooling water jacket 18.
The cooling water pump 30 may be attached to the cooling water pump 30 at the same time as the sealing member such as the O-ring 32 is sandwiched therebetween and pressed to join the suction port 30 c and the cooling water outlet 29. .

[Brief description of the drawings]

FIG. 1 is a vertical sectional front view showing an embodiment of the present invention.

FIG. 2 is a plan sectional view taken along line II-II of FIG.

FIG. 3 is an enlarged sectional view taken along line III-III of FIG. 2;

FIG. 4 is a sectional view taken along line IV-IV of FIG.

FIG. 5 is a sectional view showing another embodiment of the present invention.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Internal combustion engine 2 Crankshaft 3 Cylinder bore axis 5 Cylinder block 6 Cylinder head 7 Head bolt 8 Intake port 9 Intake valve 10 Exhaust port 11 Exhaust valve 18 First cooling water jacket in cylinder head 19 Second cooling water jacket in cylinder head 20 Air vent Hole 21 Through hole 22 Cooling water jacket in cylinder block 23 Thermostat valve chamber 24 Radiator 25 Cooling water outlet pipe 26 Cooling water inlet pipe 27 Bypass passage 28 Thermostat valve 29 Cooling water outlet 29a Peripheral surface of cooling water outlet 30 Cooling water pump 30b Cooling Water pump discharge port 30c Cooling water pump suction port 30c 'Peripheral surface of suction port 32 O-ring

Claims (2)

(57) [Claims] 1. A cooling water jacket in a cylinder head fastened to an upper surface of a cylinder block, a first cooling water jacket extending in a direction of a cylinder row on an intake port side, and a second cooling jacket extending in a direction of a cylinder row on an exhaust port side. A cooling water inlet from a radiator at one end of the first cooling water jacket, and a cooling water outlet at the other end of the first cooling water jacket and a cooling water jacket of a cylinder block. A cooling water pump for sending cooling water from the first cooling water jacket to the cooling water jacket of the cylinder block, and the second cooling water jacket is provided with the second cooling water from the cooling water jacket of the cylinder block. A cooling device for an internal combustion engine comprising an outlet to a radiator for cooling water flowing into a water jacket. The cooling water pump having a water suction port and a discharge port is attached to a side surface of the cylinder block so that the discharge port communicates with a cooling water jacket of the cylinder block, and the cylinder head of the cylinder head is A cooling water outlet of the first cooling water jacket is opened at a portion exposed from the block, and a suction port of the cooling water pump is extended toward a cooling water outlet of the first cooling water jacket. a suction port peripheral surface of the peripheral surface of the cooling water outlet of the first cooling water jacket, at the attachment of the cooling water pump for fastening or cylinder block of the cylinder head to the cylinder block, each other across a sealing material therebetween Press the cooling water outlet in the first cooling water jacket and the suction in the cooling water pump. Cooling device in an internal combustion engine, characterized in that bonding the write port. 2. A thermostat valve chamber communicating with a cooling water inlet to the first cooling water jacket is formed in the cylinder head, and a thermostat valve is provided in the thermostat valve chamber. 1) A cooling device for an internal combustion engine according to [1].