JPH037562Y2 - - Google Patents

Description

[Detailed Description of the Invention] A. Purpose of the Invention (1) Field of Industrial Application The present invention relates to a cooling device for a cylinder head that constitutes a part of the engine body of a multi-cylinder internal combustion engine.

(2) Prior Art A cylinder head of a water-cooled multi-cylinder internal combustion engine in which a water jacket is formed above a plurality of combustion chambers is already known, for example, as disclosed in Japanese Patent Application Laid-open No. 79141/1983. It is.

(3) Problems to be solved by the invention In recent years, there has been a strong demand for multi-cylinder internal combustion engines, especially those for automobiles, to be smaller and lighter, and one way to achieve this is to A cylinder with the gap as narrow as possible has appeared, as seen in the Siamese cylinder. However, if this is done, the spacing between the combustion chambers in the cylinder head will become narrower, increasing the heat load around the combustion chambers, and the rigidity of the cylinder head as a whole will decrease due to thinning of the cylinder head, especially between adjacent combustion chambers. There is a problem of inviting

The present invention has been developed in view of the above-mentioned circumstances, and is intended to improve the water cooling performance of light alloy cylinder heads, especially around the combustion chambers, as well as increase the rigidity of the cylinder heads in multi-cylinder internal combustion engines with a simple structure. The purpose is to provide a cooling device.

B. Structure of the invention (1) Means for solving the problems In order to achieve the above object, the invention includes a plurality of combustion chambers arranged on the bottom wall and a water jacket formed over the combustion chambers. In a cylinder head of a multi-cylinder internal combustion engine, the bottom surface of the water jacket between adjacent combustion chambers integrally connects the outer peripheral walls of adjacent intake valve seat portions of both combustion chambers. A first guide rib piece and a second guide rib piece connecting the outer circumferential walls of adjacent exhaust valve seat portions of both combustion chambers are integrally erected, and the bottom wall of the water jacket A first cooling water inlet facing the side surface of the first guide rib piece and a second cooling water inlet facing the side face of the second guide rib piece are opened. .

(2) Effect Cooling water flowing into the water jacket from the first cooling water inlet is guided by the first guide rib piece.
The cooling water that has flowed into the water jacket from the second cooling water inlet can be actively guided to the outer circumferential wall of the adjacent intake valve seat portions of both adjacent combustion chambers, and the cooling water that has flowed into the water jacket from the second cooling water inlet can be guided to the second guide rib piece. Accordingly, the exhaust gas can be positively guided to the outer circumferential walls of the adjacent exhaust valve seat portions of both combustion chambers. Therefore, the guide rib piece itself, which has each cooling water inlet facing toward the side surface and is relatively easily cooled, is in contact with the outer circumferential wall of the valve seat portion, and the thermal conductivity therebetween is good. It is possible to effectively cool the intake and exhaust valve seats, which tend to overheat.

Furthermore, by integrally connecting the relatively rigid outer circumferential walls of the adjacent valve seat portions of both combustion chambers through the guide rib pieces, the outer circumferential walls of the adjacent valve seat portions are mutually reinforced. With a matching shape, the water jacket itself can be effectively reinforced.

In particular, each guide rib piece connects the outer circumferential walls of the valve seat portions of valve ports of the same type with relatively similar temperature trends, and the cooling water inlets are directed separately to the side surfaces of each guide rib piece. Therefore, the direction and opening area of each cooling water inlet can be set in accordance with the temperature trend of the outer circumferential wall of the valve seat portion of the valve port of the same type.

(3) Examples Examples of the present invention will be described below with reference to the drawings.

An aluminum alloy cylinder head 1 constituting the head of the engine body of a four-valve, four-cylinder internal combustion engine is polymerized and bonded onto a cylinder block 2 via a gasket, as shown in FIG. A plurality of combustion chambers 3 are arranged on the bottom wall, and their open lower surfaces open into the cylinders 4 of the cylinder block 2.

The upper wall of each combustion chamber 3 has intake valve ports 6, 6 having a pair of valve seats ₆₁ , ₆₁ which are opened and closed by intake valves 5, 5, and intake valve ports 6, 6 which are opened and closed by exhaust valves 7, 7. Exhaust valve ports 8 and 8 having a pair of valve seats 8 ₁ and 8 ₁ are arranged opposite to each other, and a pair of intake valve ports 6 and 6 are communicated with a bifurcated intake port 9 formed in the cylinder head 1 . ,
Further, the pair of exhaust valve ports 8, 8 communicate with a bifurcated exhaust port 10 formed in the cylinder head 1.

A screw hole 11 is bored in the center of each combustion chamber 3, and a spark plug 12 is screwed into the screw hole 11. The lower half of the spark plug 12 is located above the upper wall of the combustion chamber 3. The plug is housed in an extending hollow cylindrical plug housing tube 13.

A water jacket 14 is formed in the cylinder head 1 along the direction in which the plurality of combustion chambers 3 are arranged. The outer circumferential wall and the outer circumferential walls of the plurality of plug accommodating cylinders 13 directly face each other.

As shown in Figures 3 to 5, adjacent combustion chambers 3, 3
In between, a pair of intake and exhaust side cooling water inlets 15i and 15e are bored in the bottom wall ₁₁ of the cylinder head 1, and the exhaust side inlet 15e is connected to the intake side inlet 15.
It has a larger diameter than i. These inlets 15i, 1
5e is perpendicular to the arrangement direction of the plurality of combustion chambers 3 and is inclined upwardly toward the center of the water jacket 14 to communicate with the water jacket 14, as shown in FIG. A portion of the cooling water flows into the water jacket 14 through the pair of inlets 15i and 15e. Between the adjacent combustion chambers 3, 3, on the bottom surface of the water jacket 14, a hole is provided on the bottom surface of the water jacket 14 along the arrangement direction of the plurality of combustion chambers 3, that is, approximately perpendicular to the inclination direction of the pair of cooling water inlets 15i, 15e. A pair of guide rib pieces 16i, 16e
is erected, and both ends of one guide rib piece 16i are
It is connected to the outer circumferential wall of the valve seat 6 ₁ , 6 ₁ portion of each intake port 9 , 9 of the adjacent combustion chambers 3 , 3 , is integrally connected to those outer circumferential walls, and is connected to the other guide rib piece 1 .
Both ends of 6e are connected to the outer circumferential walls of the valve seats 8 ₁ , 8 ₁ portions of the respective exhaust ports 10 , 10 of the adjacent combustion chambers 3 , 3 , and are integrally coupled to those outer circumferential walls. Further, the side surfaces of the pair of guide rib pieces 16i, 16e face the outlets of the pair of cooling water inlets 15i, 15e, and the cooling water flowing into the water jacket 14 from the inlets 15i, 15e is ,4
As shown by arrows in the figure, a pair of guide rib pieces 16i,
After colliding with the side surface of 16e, the flow is guided by the side surface and divided to the left and right, leading to intake and exhaust ports 9, 9;
It flows toward the outer peripheral wall of the valve seats 6 ₁ , 6 ₁ ; 8 ₁ , 8 ₁ of valve seats 0, 10.

Further, both ends of the pair of guide rib pieces 16i, 16e are integrally connected to the outer circumferential walls of the intake and exhaust ports 9, 9; 10, 10, and serve as reinforcing members for the water jacket 14.

An outlet 17 for the water jacket 14 is formed at one end of the cylinder head 1 (the right end in FIG. 4).

In the figure, 18 is a cooling water outlet opened on the top surface of the cylinder block 2, 19 is another water jacket formed in the cylinder head 1, and 20 is a cooling water outlet.
21 is a bolt hole, and 21 is a plug for closing the opening of the water jacket 14.

Next, the operation of this embodiment will be explained.

A part of the cooling water from the water jacket outlet 18 on the cylinder block 2 side passes through a pair of cooling water inlets 15i and 15e between the adjacent combustion chambers 3, and flows into the water jacket 1 on the cylinder head 1 side.
4. The cooling water that has flowed into the water jacket 14 hits the side surfaces of the guide rib pieces 16i and 16e as shown by the arrows in FIGS. The flow flows along the outer peripheral walls of the valve seats 6 ₁ , 6 ₁ ; 8 ₁ , 8 ₁ of the valve seats 6 1 , 6 1 ; 8 1 , 8 1 of the valve seats 9, 9; Valve seat 6
₁ , 6 ₁ ; 8 ₁ , 8 ₁ can be effectively cooled. Also, both ends of the guide rib pieces 16i and 16e are sucked,
By being integrally connected to the outer circumferential walls of the exhaust ports 9, 9; 10, 10, the rigidity of the jacket 14 is improved, and the jacket 14 can be made thinner.

In the above embodiment, the intake and exhaust ports 9,
10 constitutes a valve port in the present invention.

C. Effects of the invention As is clear from the above embodiments, according to the invention, in the cylinder head of a multi-cylinder internal combustion engine, the bottom surface of the water jacket between adjacent combustion chambers is provided with a , a first guide rib piece that integrally connects the outer circumferential walls of adjacent intake valve seat portions, and a second guide piece that also connects the outer circumferential walls of adjacent exhaust valve seat portions of both combustion chambers. The bottom wall of the water jacket has a first cooling water inlet oriented toward the side surface of the first guide rib piece, and a first cooling water inlet oriented toward the side surface of the second guide rib piece. Since the second cooling water inlet is opened, the cooling water flowing into the water jacket from the first cooling water inlet is directed to the adjacent intake air of both combustion chambers by the first guide rib piece. It can be actively guided to the outer peripheral wall of the valve seat part, and the second
The cooling water that has flowed into the water jacket from the cooling water inlet can be actively guided to the outer circumferential wall of the adjacent exhaust valve seat portion of both combustion chambers by the second guide rib piece. In addition, the guide rib piece itself, which has each cooling water inlet facing toward the side surface and is relatively easily cooled, is in contact with the outer circumferential wall of the valve seat portion and has good thermal conductivity therebetween, and this together with the fact that the combustion chamber This allows for effective cooling of the intake and exhaust valve seats, which are particularly susceptible to heating and can cause problems such as seizure, so even if the distance between adjacent combustion chambers is narrowed, cooling around the combustion chambers will be improved. This can greatly improve the performance and contribute to making the engine body lighter and smaller. Moreover, by integrally connecting the adjacent outer circumferential walls of the relatively rigid valve seat portions of both combustion chambers via the guide rib pieces,
The outer circumferential walls of the adjacent valve seat portions are mutually reinforcing, thereby effectively reinforcing the water jacket itself, which contributes to the thinning of the jacket, and also reduces the thickness of each guide. The rib pieces serve both as reinforcing ribs for the water jacket and as the cooling water guiding means as described above.
This makes it possible to simplify the internal structure of the cylinder head and contribute to cost reduction.

In particular, each of the guide rib pieces connects the outer circumferential walls of the valve seat portions of valve ports of the same type with relatively similar temperature trends, and the cooling water inlets are directed separately to the side surfaces of each of the guide rib pieces. Therefore, it is possible to set the direction and opening area of each cooling water inlet according to the temperature trend of the outer peripheral wall of the valve seat part of the same type of valve port, and therefore, it is possible to set the direction and opening area of each cooling water inlet in accordance with the temperature trend. This allows for efficient cooling.

[Brief explanation of the drawing]

The drawings show one embodiment of the present invention; FIG. 1 is a bottom view of a part of the cylinder head, and FIG. 2 is a partial bottom view of the cylinder head.
3 is a sectional view taken along the line in FIG. 1, and FIG. 4 is a sectional view taken along the line shown in FIG. 2. 3... Combustion chamber, 6 ₁ , 8 ₁ ... Valve seat, 9, 10...
... Suction and exhaust ports, 14... Water jacket, 15i, 15e... First and second cooling water inlets, 16i, 16e... First and second guide rib pieces.

Claims (1)

[Scope of utility model registration request] In a cylinder head of a multi-cylinder internal combustion engine in which a plurality of combustion chambers 3 are arranged on the bottom wall and a water jacket 14 is formed on the combustion chambers 3, the water jacket between adjacent combustion chambers 3 is provided. On the bottom surface of the butt 14, there is a first guide rib piece 16i that integrally connects the outer circumferential walls of the adjacent intake valve seats ₆₁ of both combustion chambers, and a first guide rib piece 16i that integrally connects the outer peripheral walls of the adjacent intake valve seats 61 of both combustion chambers 3. A second guide rib piece 16e connecting the outer peripheral walls of _one portion of the exhaust valve seat 8 is integrally provided, and a side surface of the first guide rib piece 16i is provided on the bottom wall of the water jacket 14. A cylinder head in a multi-cylinder internal combustion engine, characterized in that a first cooling water inlet 15i facing toward the cylinder head and a second cooling water inlet 15e facing the side surface of the second guide rib piece 16e are opened. Cooling system.