JPS6126579Y2 - - Google Patents

Description

[Detailed Description of the Invention] This invention relates to a cooling device for a multi-cylinder engine.

In general, in multi-cylinder automobile engines, most of the engine cooling employs a water cooling method using cooling water that is forcibly circulated by a water pump.

For example, as shown in FIGS. 1 and 2, cooling water is transferred from the water jacket 2 of the cylinder block 1 to the water jacket 4 of the cylinder head 3 through the water holes 5 and 4, respectively.
6 and from there to the cylinder head 3.
The cooling water passes through the radiator 7 provided at the front of the engine through the cooling water outlet 3A of the engine, and is cooled by the cooling fan 8 arranged at the rear of the radiator 7 while passing through the radiator 7. The engine is cooled by circulating the water again to the water jacket 2 of the cylinder block 1 by the water pump 9 installed in the passage connecting it to the cooling water inlet 1A.
(See Publication No. 72239).

However, in such a conventional water cooling device, the cross-sectional area of the water passages of the water holes 5 and 6 communicating with the water jackets 2 and 4 of the cylinder block 1 and the cylinder head 3 is the same. ,
Considering the arrangement of these water holes 5 and 6, the cooling water from the radiator 7 provided at one end (usually in front of the engine) flows more rapidly and in larger amounts as it is closer to the water pump 9 of the cooling system. , Conversely, the farther away from the radiator 7 the flow is, the slower and smaller the amount.

For this reason, the parts of the engine that are close to the water pump 9 are well cooled, and the farther away they are, the less they are cooled, resulting in uneven cooling in various parts of the engine.
Such uneven cooling causes thermal deformation due to temperature differences in a multi-cylinder engine, shortening the life of the engine, and this phenomenon becomes more pronounced as the number of cylinders increases.

As a countermeasure to this problem, there is an idea to eliminate uneven cooling and keep the engine temperature constant by using a large-capacity water pump, but this would be very difficult from a structural, price, and weight standpoint. It will be disadvantageous. In addition, we changed the shape and size of the water holes 5 and 6 (which usually also serve as core supports) in the cylinder block 1 and cylinder head 3, which are absolutely necessary for casting, and partially adjusted the amount of cooling water depending on the temperature. However, it is difficult to reduce or eliminate these water holes 5 and 6 in terms of casting (core positioning, etc.) or processing (core sand removal work). , 6, etc. It is difficult to adjust the temperature by changing the size, etc.

On the other hand, as disclosed in Japanese Utility Model Publication No. 52-37729, by changing the area of the water passage hole formed in the gasket or shim inserted between the cylinder head and the cylinder block,
Some devices control the amount of water, but in these cases, gaskets and shims can become deformed or damaged by the pressure of the cooling water after long-term use, which poses a practical problem in terms of durability. There was.

Therefore, in this invention, the water holes are formed in a uniform size at least among the same members, while one of the water holes is shifted by a predetermined distance in the longitudinal direction of the engine with respect to the corresponding other water hole. The purpose of the present invention is to solve the above-mentioned problems by increasing the cross-sectional area of the water passage, which is determined by the total amount of corresponding water holes, as the distance from the water pump increases.

Hereinafter, embodiments of this invention will be described based on the drawings.

Figures 3 and 4 show this invention applied to a four-cylinder engine, where 1 is a cylinder block, 2 is a water jacket formed inside the cylinder block, and 2 is a water jacket formed inside the cylinder block.
3 is the cylinder head, 4 is the same water jacket, 7 is the radiator, 8 is the cooling fan, and 9 is the water pump, which are the same as in FIGS. 1 and 2.

Reference numerals 5 and 6 designate a plurality of elongated water holes formed in the joint surfaces of the cylinder block 1 and the cylinder head 3 to communicate the water jackets 2 and 4.

These water holes 5 and 6 are each formed to the same (unified) size necessary for casting (core sand removal work), and in this invention, the water holes 5 and 6 that correspond to each other are also formed to have the same size. It has size.

The water hole 5 on the cylinder block 1 side is
They are formed in advance by being shifted by a predetermined distance in the longitudinal direction of the engine (in front of the engine) with respect to the corresponding water holes 6 on the cylinder head 3 side, and when the engine is assembled, the combined amount of the corresponding water holes 5 and 6 is The determined cross-sectional area of the water passage increases as the distance from the water pump 9 increases, as shown in FIGS. 5A to 5D. Note that the hatched area in FIG. 5 is the combined amount of the water holes 5 and 6 (that is, the size of the cross-sectional area of the water passage).

The cross-sectional area of the water passage, in other words, the amount of displacement of the water holes 5 with respect to 6, is selected in consideration of the position of the cooling water outlet 3A of the cylinder head 3 and the temperature distribution of the entire engine, so that the amount of cooling water in each part is appropriate. Needless to say.

In the figure, 1A is a cooling water inlet of the cylinder block 1, and 10 is a cylinder head gasket having a water passage hole 10A of the same size as the water hole 6 of the cylinder head 3.

With this configuration, the engine cooling water cooled by the cooling fan 8 while passing through the radiator 7 is pumped by the water pump 9 to the water jacket 2 from the cooling water inlet 1A of the cylinder block 1, and then the water is The water flows into the water jacket 4 of the cylinder head 3 through the holes 5 and 6, and is then circulated back to the radiator 7 from the cooling water outlet 3A.

In this invention, the cross-sectional area of the water passage, which is determined by the combined amount of the water holes 5 and 6, is smaller in areas closer to the radiator 7 and water pump 9 and easier for water to flow, and conversely, in areas farther away and more difficult for water to flow. As the size of the engine increases, the amount of cooling water in each part of the engine can be properly controlled, allowing the cooling water to flow within the engine according to the temperature and uniformly cooling the entire engine.

In this way, the amount of cooling water is properly controlled, so
A large-capacity water pump 9 or the like is not required.

Further, since the water holes 5 and 6 do not need to be removed by changing their sizes, the ease of casting or machining of the cylinder block 1 and cylinder head 3 can be maintained as before.

As explained above, according to this invention, the entire engine can be cooled uniformly by simply changing the combined amount of the corresponding water holes, thereby preventing thermal deformation due to temperature differences in a multi-cylinder engine. This has the effect of improving durability.

In addition, since the gasket can have the same shape as either water hole, the pressure of the cooling water does not act directly on the gasket, so durability is not compromised and stable performance can be maintained over a long period of time. Can be done.

[Brief explanation of the drawing]

Figures 1 and 2 are front and partially omitted plan views of the conventional device, Figures 3 and 4 are front and partially omitted plan views of this invention, and Figures 5A to 5D are the total amount of water holes. FIG. 1... Cylinder block, 3... Cylinder head, 2, 4... Water jacket, 7... Radiator, 9... Water pump, 5, 6... Water hole.

Claims (1)

[Scope of utility model registration request] A water pump is installed in the cooling system consisting of water jackets formed on the cylinder block and cylinder head, and a radiator etc. connected to these water jackets, so that engine cooling water is forcedly circulated through the cooling system by this water pump. In a cooling system for a multi-cylinder engine, each of the water holes communicating between the cylinder block and the water jacket of the cylinder head is formed with a uniform size at least between the same members, while one of the water holes is made to correspond to each other. The water holes are formed to be shifted by a predetermined distance in the longitudinal direction of the engine with respect to the other water hole, and the cross-sectional area of the water passage, which is determined by the combined amount of the corresponding water holes, increases as the distance from the water pump increases. A cooling system for internal heat engines.