KR20100018868A - Water jacket structure of gasoline direct injection engine for cooling injector - Google Patents

Abstract

PURPOSE: A water jacket structure for cooling an injector of a gasoline direct injection engine is provided to prevent an injector from being overheated due to heat generated by the combustion of a mixer by letting cooling water flow through a water jacket formed near the injector. CONSTITUTION: A water jacket structure for cooling an injector of a gasoline direct injection engine comprises a water jacket. The water jacket is formed near the upper part of an injector mounting part(110) of a cylinder head used in a gasoline direct injection engine. The water jacket is formed to move cooling water along the longitudinal direction of the cylinder head.

Description

Water jacket structure of Gasoline Direct Injection engine for cooling injector}

The present invention relates to a structure of a water jacket formed inside a cylinder head, and more particularly, to a structure of a water jacket for effectively injector cooling of a gasoline direct injection (GDI) engine.

In general, the main goal we are pursuing for all engines, not just gasoline engines, is to reduce operating costs and reduce harmful emissions while still getting maximum output at the same displacement.

As a technique for realizing ultra-lean combustion for the purpose of reducing fuel, a method of pursuing lean combustion by directly injecting into a cylinder and stratifying the mixer by forming an appropriate cylinder flow (forming a partially enriched mixer) There is a direct injection gasoline (GDI) engine.

The GDI engine is an engine for preventing environmental pollution, and there is a big difference between the MPI (Multi Point Injection) engine and the injection method that are currently used the most. The MPI engine injects fuel from an injector at each port of the inlet port, so that a mixture of air and fuel enters the cylinder. However, the GDI engine overcomes this limitation by allowing gasoline to be injected directly into the cylinder's combustion chamber through the cylinder head, just like a diesel engine, and can precisely adjust the timing of fuel injection.

On the other hand, the cylinder head is provided with an intake / exhaust port and forms a combustion chamber exposed to high temperature combustion gas of 2000 ° C. or higher to prevent deterioration and squeeze of intake / exhaust valves for opening and closing the intake / exhaust port of the cylinder head. In order to cool the cylinder head, a water jacket is formed.

In addition, a water jacket is formed at the lower side of the intake port for cooling the intake port side that receives relatively less thermal load, and water is heated up and down the exhaust port for cooling the exhaust port side receiving high temperature exhaust gas heat. I form a jacket.

In addition, since the 2-valve head structure is insufficient for the regulation of the exhaust gas emissions, a 4-valve head method is adopted to increase the intake filling efficiency and the combustion efficiency to achieve high output and reduce the exhaust gas emission amount.

However, since the GDI Injector mounted on the conventional GDI engine is injected directly into the combustion chamber, the GDI injector directly receives heat generated from the combustion chamber and thus does not effectively remove the thermal load.

That is, the interest in the cooling of the cylinder head so far has been mainly the cooling of the exhaust port portion and the combustion chamber peripheral, since the heat source generation point in the cylinder head was mainly the combustion chamber and the exhaust port. However, the cooling structure in the injector mounted on the GDI engine does not yet have. As a result, when the engine is overheated due to a local temperature rise, a phenomenon such as deformation of parts, breakdown of lubricant film, lack of lubricating oil, and decrease of engine output occurs, and when the engine is overcooled, output decreases and fuel consumption rate. Increases, oil dilution and abrasion of bearing parts occur. This results in a decrease in the density of the air, which leads to a decrease in combustion performance, which results in a decrease in output performance in relation to the engine output.

Accordingly, the present invention has been made to solve the problems as described above, and an object of the present invention is to inject the cooling of the injector of the GDI engine that can cool the heat biased to the injector of the GDI engine by the heat of combustion in the combustion chamber of the cylinder. It is to provide a water jacket structure for.

The water jacket structure for cooling the injector of the GDI engine according to the embodiment of the present invention for achieving this object is formed in close proximity to the upper side of the injector mounting portion of the cylinder head used for the gasoline direct injection (GDI) engine In the water jacket formed to move the coolant along the longitudinal direction of the cylinder head, the cross section of the water jacket may be formed to have an inclination corresponding to the inclined angle of the injector.

The water jacket may further include a narrow portion that is narrower in cross section as the water jacket approaches the injector.

The water jacket may have a slope of 0 degrees to 45 degrees.

At least one coolant fin may be further included on both sides of the injector mounting unit with respect to the injector.

As described above, according to the water jacket structure for injector cooling of the GDI engine according to the present invention, the coolant flows through a water jacket formed in close proximity to the injector of the GDI engine, thereby overheating the injector due to heat generated by combustion of the mixer. You can prevent it.

In addition, since the operation of the injector is smoothly prevented due to overheating of the injector, there is an effect of preventing premature ignition, improving filling efficiency, preventing deformation and cracking, and smoothing of lubrication.

Furthermore, it has the effect of lowering the tip temperature of the injector, thereby increasing the efficiency of the injector.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

1 is a plan view illustrating a water jacket according to an embodiment of the present invention, FIG. 2 is a cross-sectional view taken along line II-II of FIG. 1, and FIG. 3 is a line taken along line III-III of FIG. 1. 4 is a cross-sectional view showing the inside of the cylinder head formed with a water jacket according to an embodiment of the present invention, Figure 5 is a front view showing the shape of the water jacket according to another embodiment of the present invention, FIG. 6 is a side cross-sectional view taken along line VI-VI of FIG. 5.

1 to 4, the water jacket 200 for cooling the injector of the GDI engine according to an embodiment of the present invention is a cylinder in close proximity to the upper side of the injector mounting portion 110 formed on one side of the cylinder head 100 It is formed to flow in the longitudinal direction of the head 100.

When the injector 120 is mounted on the injector mounting unit 110, the water jacket 200 may be formed such that its cross section gradually decreases as it approaches the injector 120.

In addition, in order to increase the cooling effect of the injector 120, the cross section of the water jacket 200 may be formed in the longitudinal direction of the injector 120. That is, the cross section of the water jacket 200 may be formed to form an inclination corresponding to the inclined angle of the injector 120. In this case, since the contact area between the water jacket 200 and the injector 120 is widened, the injector 120 is cooled effectively.

Here, as shown in FIG. 2, the area of the water jacket 200 on the upper side of the injector 120 is gradually reduced to eventually form a narrow portion 210 having a minimum cross-sectional area when reaching the vertical direction of the injector 120. If the cross-sectional area is increased toward both sides with the narrow portion 210 as the center, the heat load of the injector 120 can be effectively reduced by inducing the cooling water flow rate enhancement and the heat transfer promotion around the injector 120. . 2 and 3, the water jacket inclination angle (R) is designed according to the injector inclination angle (IR), such a water jacket inclination angle (R) is formed from 0 degrees to 45 degrees in consideration of the operating conditions It is preferable.

That is, the piston head forming the upper part of the injector inclination angle IR and the piston (not shown) disposed inside the cylinder block in consideration of the injection delivery distance and the injection angle of the fuel by the injector 120 when designing the GDI engine ( Since the fuel flows around the spark plug only when the swirl flow is properly generated by the combination of the shapes, the optimum water jacket inclination angle R is determined according to the inclination angle of the injector 120 calculated accordingly. It must be done.

As shown in FIG. 4, when the cylinder head 100 is mounted on the upper side of the cylinder block (not shown) having the water jacket 200, and the head bolt (not shown) is fastened and assembled, the water jacket 200 is assembled. Since the injector 120 is formed in close proximity to the portion mounted in the combustion chamber C, the injector 120 is mounted directly in the combustion chamber C to directly receive the heat of combustion generated in the combustion chamber C. Minimize your concentration. Therefore, not only the power loss is reduced, but also unnecessary combustion of the engine oil is prevented, and the consumption of the engine oil is reduced.

Meanwhile, FIGS. 5 and 6 illustrate another embodiment of the present invention, wherein a plurality of cooling fins 300 toward the injector mounting unit 110 are further formed around the injector mounting unit 110 to cool the water. As the heat exchange is circulated inside the jacket 200 and the heat exchange is performed at the same time, the heat exchange area is widened by the cooling fins 300, thereby rapidly increasing the heat exchange, thereby further increasing the cooling effect.

Although the preferred embodiments of the present invention have been described above, the present invention is not limited to the above embodiments, and easily changed and equalized by those skilled in the art from the embodiments of the present invention. It includes all changes to the extent deemed acceptable.

1 is a plan view of a water jacket according to an embodiment of the present invention.

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

3 is a cross-sectional view taken along the line III-III of FIG.

Figure 4 is a cross-sectional view showing the inside of the cylinder head implemented a water jacket according to an embodiment of the present invention.

5 is a front view showing the shape of the water jacket according to another embodiment of the present invention.

6 is a cross-sectional view taken along the line VI-VI of FIG. 5.

* Explanation of Signs of Major Parts Used in Drawings *

R: Water Jacket Tilt Angle IR: Injector Tilt Angle

C: combustion chamber 100: cylinder head

110: injector mounting portion 120: injector

200: water jacket 210: narrow part

300: cooling fin

Claims (4)

In the water jacket which is formed in close proximity to the upper side of the injector mounting portion of the cylinder head used for the gasoline direct injection (GDI) engine, the cooling water is moved along the longitudinal direction of the cylinder head, The water jacket structure for injector cooling of the GDI engine, characterized in that the cross section of the water jacket is formed to form a slope corresponding to the inclined angle of the injector. The method of claim 1, The water jacket structure of the water jacket for injector cooling of the GDI engine, characterized in that it further comprises a narrow portion that narrows the cross section closer to the injector. The method of claim 1, The water jacket structure of the water jacket for injector cooling of the GDI engine, characterized in that the inclination of the cross section is made from 0 degrees to 45 degrees. The method of claim 1, Water jacket structure for injector cooling of the GDI engine, characterized in that it further comprises at least one coolant fin mounted around the injector mounting portion.

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