JPS6233405B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an internal combustion engine for a motorcycle, in particular an engine block mounted on a body frame, which includes a cylinder head having an intake system and an exhaust system connected to one side and the other side, respectively, and The present invention relates to a cooling device for a cross-flow type water-cooled internal combustion engine, which is comprised of a cylinder block having a head superimposed on the upper surface thereof via a gasket.

In the above type of internal combustion engine, the cooling water passage in the engine block is generally connected to the cylinder block.
A cylinder side water jacket provided to surround a cylinder hole formed therein and a head side water jacket formed to surround a combustion chamber formed therein are communicated via a gasket to the cylinder head. Cooling water from the radiator is introduced into the head side water jacket from the cylinder side water jacket through the inlet port drilled in the cylinder block to cool the cylinder block and cylinder head, and after cooling them, the cooling water is introduced into the cylinder head. The air is configured to flow back to the radiator through a drilled outflow port. However, in a cross-flow type internal combustion engine, even if the above-mentioned water cooling structure is adopted, there is still a problem in that the half of the cylinder head on the exhaust system side is easily heated by the exhaust gas and reaches a particularly high temperature.

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, it is an object of the present invention to provide a device capable of extremely effectively cooling the exhaust system side half of the cylinder head.

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment in which the present invention is applied to a water-cooled multi-cylinder V-type four-stroke internal combustion engine for a motorcycle will be described below with reference to the drawings.

The cross-flow type internal combustion engine E is mounted horizontally on the body frame F of a motorcycle (with its crankshaft 1 perpendicular to the longitudinal direction of the body frame F). The first engine block B ₁ tilts forward.
, a second engine block B ₂ tilting toward the rear of the vehicle body frame F, and both engine blocks
It is connected to the lower part of B ₁ and B ₂ and has a common crankcase 2, and a V-shaped space C is formed between the first and second engine blocks B ₁ and B ₂ when viewed from the side. Ru. First and second engine blocks B ₁ ,
_B2 is constructed by integrally connecting a cylinder head 4 onto a cylinder block 3 via a gasket 5 as usual. An intake system In and an exhaust system Ex are connected to one side and the other side of each cylinder head 4 in the longitudinal direction of the vehicle, respectively, and the intake systems In of each head 4 are collectively arranged in the V-shaped space C.

A crankshaft 1 is provided on one side of the crankcase 2.
A cooling water pump 8, which is also driven by the crankshaft 1, is disposed behind the generator 7, which is driven by the crankshaft 1. In addition, a radiator 9 is supported on the down tube 6 of the vehicle body frame F.
The radiator 9 and the cooling water pump 8 are connected through a cooling water channel which will be described in detail below.

Next, to explain the configuration of this cooling water passage, a suction pipe 12 and a discharge pipe 13 are connected to the suction port 10 and discharge port 11 of the cooling water pump 8, respectively. The opening end thereof extends forward along the down tube 6 of the rear vehicle body frame F and is connected to the outlet 14 of the radiator 9, and after the discharge tube 13 also wraps around the outer periphery of the lower surface of the generator 7, the first, 2nd engine block
It faces the valley of the V-shaped space C between B ₁ and B ₂ ,
Its open end is connected to the intake system In of each cylinder block 3.
Cooling water inflow port 1 opened at the bottom of the outer surface of the side
6 and 16 (Fig. 2).

Cooling water outflow ports ₁₇ , 17 ( _second
Figure) shows water conduit pipes 18, 18 and flexible hose 1.
It communicates with the inlet 15 of the radiator 9 via 9 and 19.

Cooling water passages W, W through which cooling water circulates are formed in the first and second engine blocks B ₁ and B ₂ . Next, the structure of the cooling water passage W will be explained in detail.

As shown in Fig. 3, each engine block B ₁ ,
The cylinder block 3 of B ₂ has two cylinder holes 2 parallel to each other along the axial direction of the crankshaft 1.
0, 20 are formed, and a cylindrical cylinder side water jacket 21 surrounds each cylinder hole 20.
Further, the inflow port 16 communicating with the cylinder side water jacket 21 is bored in the lower part of the cylinder block 3 on the side of the V-shaped space C. The cylinder side water jacket 21 is open on the upper surface of the cylinder block 3.

Further, a head-side water jacket 23 is formed in the cylinder head 4 of each engine block B ₁ , B ₂ so as to surround a combustion chamber 22 formed therein, and the outflow port 17 is further connected to the water jacket 23 . is open on the side facing the V-shaped space C, that is, on the outer surface of the intake system In side.

The head side water jacket 23 is branched into a plurality of branch waterways 23a to 23f toward the lower surface within the cylinder head 4, and these are approximately half of the exhaust system Ex side as shown in FIG. That is, in approximately half of the side away from the cooling water inlet port 16 and outlet port 17, the cylinder head 4
These branch waterways 23a to 23f are opened approximately concentrically on the lower surface of the cylinder, and these branch waterways 23a to 23f are communicated with the cylinder side water jacket 21 when the cylinder head 4 is connected to the cylinder block 3 via the gasket 5. . Each head side water jacket 23 surrounds the left and right combustion chambers 22, 22 of the cylinder head 4.
The branch waterways 23a to 23f, 23a to 23f are
It is opened symmetrically with respect to the longitudinal center line L ₁ - L ₁ perpendicular to the crankshaft 1 of the engine block 3, and 2
two branch waterways 23c and 23d, and 23b and 23
e refers to two branch water channels that pass through the center of the cylinder hole 20 and are opened symmetrically with respect to the cylinder center line L ₂ - L ₂ parallel to the longitudinal center line L ₁ - L ₁ but close to the outflow port 17. 23a and 23f are opened offset from each other by a displacement amount e in the direction of the cylinder center line L ₂ -L ₂ .

As shown in FIG. 4, a gasket 5 interposed between the cylinder block 3 and cylinder head 4 includes:
A through hole 25 having approximately the same diameter as the cylinder hole 20 is bored to communicate the cylinder hole 20 and the combustion chamber 22, and the cylinder side water jacket 21 and the head side water jacket 23 are connected to each other on the outer periphery thereof. A plurality of water passages 26a to 26f are bored, and these water passage holes 26a to 26f are aligned with the vertical center line L ₁ -
It is symmetrical about L ₁ . Also, water holes 26c and 2
6d, 26b and 26e, and 26a and 26f are all symmetrical with respect to the cylinder center line L ₂ -L ₂ . If this gasket 5 is interposed between the cylinder head 4 and cylinder block 3, the branch waterway 23f closest to the cooling water outflow port 17 can be opened.
The other water holes 26 except for the water hole 26f corresponding to
a to 26e all coincide with the branch waterways 23a to 23e, and the cylinder side water jacket 21 and the head side water jacket 23 are communicated with each other, but the branch waterway 23f closest to the outflow port 17 and the corresponding water passage hole 26f are Some of them are polymerized, or they are disturbed so that they are not polymerized at all, and the branched water channel 23f is constricted or blocked by the gasket 5. The above-mentioned relationship is between the branch waterways 23a to 23f and the water holes 26a to 26.
Due to the above-described arrangement of f, there is no change even if the gasket 5 is reversed and inserted between the cylinder head 4 and the cylinder block 3, and there is no fear that the gasket 5 will be incorrectly assembled.

Note that 27 and 28 in the figure are sand removal holes formed in the cylinder head 4.

Next, the operation of the embodiment of the present invention will be explained.

When the cooling water pump 8 is driven by the operation of the internal combustion engine E, the pressurized cooling water from the pump 8 is distributed and flows into the cylinder side water jackets 21, 21 from the discharge pipe 13 through the inflow ports 16, 16. After flowing through the water jackets 21, 21, the water passes through the water holes 26a to 26f of the gasket 5 and the branch waterways 23a to 23f of the cylinder head 4, flows to the head side water jacket 23, and flows into the first and second water jackets. After cooling the engine blocks B ₁ and B ₂ , the outflow port 17,
17, water conduit pipes 18, 18, and hoses 19, 19 to flow into the radiator 9. The cooling water cooled by the radiator 9 is sucked into the cooling water pump 8 through the suction pipe 12.

By the way, in the cooling process of each engine block B ₁ and B ₂ , the cylinder side water jacket 21 and the head side water jacket 23 are
Approximately half of B ₁ and B ₂ on the exhaust system Ex side, that is, approximately the half on the side away from the inflow port 16 and the outflow port 17, are communicated via the water holes 26a to 26f and the branch waterways 23a to 23f. Therefore, the cooling water in the cylinder side water jacket 21 flows evenly into the water jacket 21 to effectively cool the cylinder block 3, and then flows into the exhaust system Ex side half of the head side water jacket 23. The exhaust gas flows into the exhaust system Ex side of the cylinder head 4, which is easily heated by exhaust gas and reaches the highest temperature among the engine blocks B ₁ and B ₂ . can be cooled extremely efficiently and reliably, and the cooling water will not flow from the inflow port 16 to the outflow port 17 due to a short circuit.

Further, the branch waterway 23f closest to the inflow port 16 and the outflow port 17 is confused with the corresponding water passage hole 26f of the gasket 5, and the branch waterway 23f is constricted or blocked. The amount of cooling water flowing into the branch channel 23f can be reduced or blocked, thereby preventing the cooling water passing through the branch waterway 23f from flowing directly to the outflow port 17.

Note that the branch waterway 23f is necessary as a sand removal hole during casting of the cylinder head 4, and cannot be omitted.

As described above, according to the present invention, the vehicle body frame F
Engine blocks B ₁ and B ₂ installed in
The cylinder block 3 is provided with a cylinder side water jacket 21 that surrounds a cylinder hole 20 formed therein, and a cooling pipe that communicates with the cylinder block 3. A water inflow port 16 is bored, and the cylinder head 4 is provided with a head side water jacket 23 that surrounds the combustion chamber 22 formed therein and communicates with the cylinder side water jacket 21. In a cooling device for a cross-flow type water-cooled internal combustion engine for a motorcycle, which is provided with a cooling water outflow port 17,
The cooling water inflow port 16 and the cooling water outflow port 17 are respectively opened on the outer surfaces of the cylinder block 3 and the cylinder head 4 on the intake system In side, and the cylinder side water jacket 21 and the head side water jacket 23 are connected to the engine block. Exhaust system for B ₁ and B ₂
Since they are connected to each other approximately in half on the Ex side, the exhaust system Ex from the cylinder side water jacket 21 to the head side water jacket 23 is connected through that communication part.
The cooling water flowing into the side half of the exhaust system of the cylinder head 4, which tends to reach the highest temperature among the engine blocks B ₁ and B ₂ and is farthest from the inlet and outlet ports 16 and 17, is extremely efficiently heated. In addition, it can be reliably cooled and is effective in preventing overheating of the Ex side half of the exhaust system.
Output ports 16 and 17 are both engine block
B ₁ and B ₂ are open on the outer surfaces of the intake system In side, and the inflow and outlet ports 16 and 16 are opened on the outer surfaces of the exhaust system Ex side.
Since there is no need for the piping to be connected to 17 to be close to each other, there is no risk that the piping will impair the air cooling effect of the running wind on the outer surface of the exhaust system Ex side of engine blocks B ₁ and B ₂ , and the cylinder head 4 This is more effective in preventing overheating of the Ex side half of the exhaust system of the cylinder head 4, and the same piping is connected to the exhaust system of the cylinder head 4.
There is no risk of deterioration due to radiant heat from the Ex side half or the exhaust system Ex itself.

Further, according to the second invention, a plurality of branch waterways 23a to 2 branch from the head side water jacket 23.
The cylinder side water jacket 21 and the head side water jacket 23 are connected to the engine block via 3f.
B ₁ and B ₂ are biased toward approximately half of the exhaust system Ex side and communicate with each other, and furthermore, the branch waterway 23f located closest to the outflow port 17 is narrowed or blocked by the gasket 5. Therefore, the cooling water flows from the inflow port 16 to the outflow port 17 via the branch waterway 23f closest to the outflow port 17.
This effectively prevents a short circuit to the side, and further enhances the above-mentioned overheating prevention effect on the exhaust system Ex side half of the cylinder head 4.

[Brief explanation of the drawing]

Fig. 1 is a side view of a motorcycle equipped with a water-cooled internal combustion engine equipped with the device of the present invention, Fig. 2 is an enlarged vertical sectional side view of the engine block of the internal combustion engine, and Fig. 3 is a side view of a motorcycle equipped with a water-cooled internal combustion engine equipped with the device of the present invention. 4 is a view taken along the line in FIG. 2. B ₁ , B ₂ ... Engine block, Ex ... Exhaust system, F ... Body frame, In ... Intake system, 3 ...
Cylinder block, 4... Cylinder head, 5...
... Gasket, 16 ... Inflow port, 17 ... Outflow port, 20 ... Cylinder hole, 21 ... Cylinder side water jacket, 22 ... Combustion chamber, 23 ... Head side water jacket, 23a to 23f ... Branch waterway .

Claims (1)

[Scope of Claims] 1. Engine blocks B ₁ and B ₂ mounted on a vehicle body frame F are provided with an intake system In and an exhaust system on one side and the other side.
It consists of a cylinder head 4 to which each Ex is connected, and a cylinder block 3 to which the cylinder head 4 is polymerized and connected to the upper surface via a gasket 5,
The cylinder block 3 is provided with a cylinder-side water jacket 21 surrounding a cylinder hole 20 formed therein, and a cooling water inlet port 16 communicating therewith is bored, and the cylinder head 4 is provided with a cooling water inlet port 16 therein. surrounding the combustion chamber 22 formed;
In the cooling device for a cross-flow type water-cooled internal combustion engine for a motorcycle, the head-side water jacket 23 is provided to communicate with the cylinder-side water jacket 21, and a cooling water outflow port 17 is formed to communicate with the head-side water jacket 23. A water inflow port 16 and an outflow port 17 are opened on the outer surface of each intake system In side of the cylinder block 3 and cylinder head 4, respectively, and the cylinder side water jacket 21 and the head side water jacket 23 are connected to the engine block _B1 . , B ₂ A cooling device for a cross-flow water-cooled internal combustion engine for a motorcycle, which is formed by connecting approximately half of the exhaust system Ex side of the exhaust systems to each other. 2 Engine blocks B ₁ and B ₂ mounted on the vehicle body frame F are connected to the intake system In and the exhaust system on one side and the other side.
It consists of a cylinder head 4 to which each Ex is connected, and a cylinder block 3 to which the cylinder head 4 is polymerized and connected to the upper surface via a gasket 5,
The cylinder block 3 is provided with a cylinder-side water jacket 21 surrounding a cylinder hole 20 formed therein, and a cooling water inlet port 16 communicating therewith is bored, and the cylinder head 4 is provided with a cooling water inlet port 16 therein. surrounding the combustion chamber 22 formed;
In the cooling device for a cross-flow type water-cooled internal combustion engine for a motorcycle, the head-side water jacket 23 is provided to communicate with the cylinder-side water jacket 21, and a cooling water outflow port 17 is formed to communicate with the head-side water jacket 23. A water inflow port 16 and an outflow port 17 are opened on the outer surface of each intake system In side of the cylinder block 3 and cylinder head 4, respectively, to form a plurality of branch waterways 23a to 23f branched from the head side water jacket 23. The cylinder side water jacket 21 and the head side water jacket 23 are communicated with each other through the cylinder side water jacket 21 and the head side water jacket 23, which are biased toward approximately half of the exhaust system Ex side of the engine blocks B ₁ and B ₂ .
Furthermore, a cooling device for a cross-flow type water-cooled internal combustion engine for a motorcycle, in which a branch waterway 23f located closest to the outflow port 17 is narrowed or blocked by the gasket 5.