JPH0510738U - Engine cooling system - Google Patents

Abstract

(57) [Abstract] [Purpose] To enable spot cooling between exhaust valves in a cylinder head by using a heat pipe. A hollow pipe portion 9 is integrally formed in the cylinder head 1 so as to extend from an area between the exhaust valves 5a and 5b around the combustion chamber 2 through the water jacket 3 to an oil chamber 7. The working fluid was enclosed in 9 to form a peat pipe 10.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a cooling system for an engine which is water-cooled and has two or more exhaust valves.

[0002]

[Prior Art]

 2. Description of the Related Art In recent years, in automobile engines, in order to reduce inertial weight and increase intake / exhaust efficiency to improve output and the like, one-cylinder, four-valve, etc. valves have been increasingly used.

In such a multi-valve engine as well, when cooling the cylinder head, as shown in FIGS. 3 and 4, engine cooling water is provided in a water jacket 3 provided around the combustion chamber 2 of the cylinder head 1. It was done by circulating it. In the figure, 4a and 4b are exhaust ports, 5a and 5b are exhaust valves, 6 is a spark plug threaded portion, and 7 is an oil chamber.

[0004]

[Problems to be solved by the device]

 In the cylinder head 1 of the multi-valve engine as described above, the water jacket 3 between the exhaust valves 5a and 5b, which has the highest temperature around the combustion chamber 2, is narrow, and the flow of engine cooling water is poor. However, there is a problem in that it is not possible to obtain a proper cooling effect, which adversely affects knock resistance and engine durability.

Therefore, an object of the present invention is to enable spot cooling of the portion between exhaust valves in a cylinder jacket using a heat pipe.

[0006]

[Means for Solving the Problems]

 In order to achieve the above object, the structure of the present invention is a water-cooled engine having two or more exhaust valves, and the oil is penetrated into the cylinder head from the exhaust valve around the combustion chamber through the water jacket. A hollow pipe portion extending to the chamber is integrally formed, and a working liquid is enclosed in the hollow pipe portion to form a heat pipe.

[0007]

[Action]

 According to the above configuration, the heat between the exhaust valves is positively heat-exchanged with the engine cooling water by the heat pipe and locally cooled.

[0008]

【Example】

 An embodiment of the present invention will be described below with reference to the accompanying drawings. FIG. 1 is a half sectional view of a cylinder head of a four-valve engine provided with two intake and exhaust valves, and FIG. 2 is a sectional view taken along line II-II of FIG. 1 and 2, the same members and parts as those in the conventional technique shown in FIGS. 3 and 4 are designated by the same reference numerals, and detailed description thereof will be omitted.

As shown in FIGS. 1 and 2, inside the cylinder head 1, a hollow pipe portion extending from the exhaust valve 5 a, 5 b portion around the combustion chamber 2 through the water jacket 3 to the oil chamber 7. 9 is integrally formed when the cylinder head is manufactured.

Then, a working liquid (not shown) is enclosed in the hollow pipe portion 9 to form a heat pipe 10. In this heat pipe 10, the working fluid in the hollow pipe portion 9 evaporates on the high temperature side and moves to the low temperature side in the hollow pipe portion 9, where heat is deprived and liquefied, and is appropriately provided in the hollow pipe portion 9. The inside of the fiber (not shown) is continuously returned by capillarity to achieve a normal function.

Other configurations are the same as those in FIGS. 3 and 4.

With this structure, the cylinder head 1 receives the heat of combustion in the combustion chamber 2 and becomes high in temperature. The heat between the exhaust valves 5a and 5b is sent by the heat pipe 10 into the water jacket 3 on the other end side of the heat pipe 10 where the engine cooling water flows well and is exchanged with the engine cooling water. In this way, in the cylinder head 1, the portion between the exhaust valves 5a and 5b, which has the highest temperature, is locally cooled, and a sufficient cooling action is obtained.

Further, since the hollow pipe portion 9 for forming the heat pipe 10 is integrally formed at the time of manufacturing the cylinder head 1, compared with the case where a commercially available heat pipe is assembled into the cylinder head 1 by screwing or casting. , Easy to manufacture.

[0014]

[Effect of the device]

 As described above, according to the present invention, the heat pipe locally cools the portion between the exhaust valves, which has the highest temperature in the cylinder head, so that a sufficient cooling action can be obtained, thus improving the knock resistance. At the same time, the engine durability is improved. Also, since the heat pipe is formed integrally with the cylinder head when manufacturing the cylinder head, it is effective in manufacturing.

[Brief description of drawings]

FIG. 1 is a half sectional view of a cylinder head showing an embodiment of the present invention.

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

FIG. 3 is a half sectional view of a conventional cylinder head.

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

[Explanation of symbols]

 1 Cylinder Head 2 Combustion Chamber 3 Water Jacket 5a, 5b Exhaust Valve 9 Hollow Pipe Part 10 Heat Pipe

Claims (1)

[Claims for utility model registration] 1. In a water-cooled engine having two or more exhaust valves, the oil chamber is penetrated from the exhaust valve around the combustion chamber to the inside of the water jacket in the cylinder head. A cooling device for an engine, characterized in that a hollow pipe portion extending to the inside is integrally formed, and a working liquid is enclosed in the hollow pipe portion to form a heat pipe.