JPS5852331Y2 - Intake port of direct injection internal combustion engine - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an improvement of a helical intake port for a two-valve direct injection internal combustion engine.

Conventionally, in order to speed up combustion and increase air utilization by creating a vortex in the air inside the cylinder of a direct injection internal combustion engine, air swirling around the cylinder axis, or so-called swirl, is created. In the case where a helical intake port is provided as a method for increasing the intake speed, there is a problem in that if an excessive air swirling speed is applied, the intake efficiency decreases and the engine performance may be deteriorated.

Therefore, there is a need for an intake port that has optimal high swirl characteristics during certain combustion conditions and can provide a high intake amount.

Therefore, in order to solve the above-mentioned problems, the present invention aims to provide a helical suction boat that can obtain a high suction amount and high swirl characteristics.

That is, the present invention provides a two-valve direct injection internal combustion engine in which the spiral shape of the intake port connected to the intake hole 4 provided off the center of the cylinder is formed so as to wind toward the center of the cylinder and toward the exhaust valve side. In the helical intake port of the engine, a substantially horizontal protrusion 5 for deflecting the intake air flow is provided on the side wall surface between the intake and exhaust valves in the intake hole 4 directly above the valve seat 6, and its edge is approximately It is constructed by protruding in a straight line.

Embodiments of the present invention will be described below with reference to the drawings.

The embodiments of the present invention shown in FIGS. 1, 2, and 3 are as follows:
There is a helical intake port 2 formed in the cylinder head 1 of a valve-type direct injection internal combustion engine, and the intake port 2 is located on the side wall surface between the intake and exhaust valves directly above the valve seat 6 in the intake hole 4 that houses the intake valve 3. A substantially horizontal protrusion 5 that diverts the flow B is attached to the cylinder head 1.
It is formed integrally with the

The protrusion 5 is provided approximately parallel to the combustion surface of the cylinder head 1, and has a lower surface forming an angle α of 00 to 45 degrees on the upper part of the valve seat 6, and a protrusion position at a height H2 from the lower surface of the valve seat. Located in
Its upper surface has a curvature R3 that connects to the intake port wall curvature R2.
It is formed by a concave surface of the air intake hole 4, and its height Hl is the same as that of the air intake hole 4.
Letting the inner hole diameter of D be D, it is set within the range of.

Next, to explain the function of the intake port 2 of the present invention having the above-mentioned protrusion 5, the upper intake air flow flowing at the inlet of the intake port 2 is roughly divided into B and the lower intake flow A. The flow A passes through the intake hole 4 and the valve seat 6 along the lower surface of the intake port 2, and flows out into the cylinder 7 all at once as an intake flow A' shown in FIG.

On the other hand, the upper intake air flow B moves downward along the spiral-shaped portion of the intake port 2 while going around the center S of the intake hole 4.

Therefore, in a conventional spiral intake port (not shown), this intake air flow B flows out toward the center O of the cylinder 7, which is located at a distance l□ and 12 from the center S of the intake child L4 in FIG. , the remaining part flowed out in the direction shown by B' in FIG. , a downward flow like the intake air flow B1 is diverted,
After the intake flow B is accumulated at the protrusion 5, it again moves downward near the valve seat 6, like the intake flow B2, and becomes the intake flow B' shown in FIG.

In this case, the direction of the intake air flow B is slightly changed in the horizontal direction by the approximately horizontal protrusion 5 provided on a part of the periphery of the inner wall of the intake hole 4, and the swirling energy of the intake air is dissipated. There are almost no

Therefore, the intake air flow B' is strengthened by the sum of the air flow A' which is flowing all at once, and flows out into the cylinder 7 as the air intake air C as if the air flow B' passes under the air intake air A'. In addition, intake air with high swirl characteristics can be obtained.

In addition, as shown in FIG. 3, since the protrusion 5 is provided between the intake and exhaust valves of the cylinder head 1 and the part where the fuel valve is installed,
Since that part is thick, there is enough space to provide the cooling water hole 8 there.

Further, a cooling water chamber may be formed in place of the perforation 8.

According to the present invention, a substantially horizontal protrusion 5 is provided on the side wall surface between the intake and exhaust valves directly above the valve seat 6 in the intake hole 4 to deflect the intake air flow.
Since the edge is protruded so that it is almost straight,
The protrusion 5 allows the intake airflow generated around the center of the intake hole 4 to be diverted without dissipating its swirling energy, and allows this intake airflow to flow into the cylinder all at once. It can be strengthened by combining with the intake air flow and flowed into the cylinder.

Therefore, it is possible to obtain intake air with a high flow rate and high swirl characteristics, which speeds up the combustion of the engine and increases the air utilization rate, which is extremely useful for improving the combustion performance of the engine. Beneficial.

Further, since the protrusion 5 is a substantially horizontal protrusion, the direction of the intake air flow is only slightly changed in the horizontal direction, and the swirling energy is hardly dissipated, so that the above-mentioned young fruit can be obtained.

Furthermore, since the protrusion 5 only needs to be provided on a portion of the periphery of the inner wall of the intake hole 4, it is easy to form and the resistance to intake hardly increases.

In addition, in the intake port of the present invention, the protrusion 5 is formed on the inner wall surface between the intake and exhaust valves, so that the cooling water chamber or cut-out hole is formed between the intake and exhaust valves, where the temperature is high even in the middle stage of engine operation, and between the fuel valves, etc. There is an advantage that it can be formed on the back surface of the protrusion 5.

Note that the present invention can be effectively applied to a helical intake port of a direct injection internal combustion engine.

[Brief explanation of the drawing]

Fig. 1 is a plan sectional view of the main part of the intake port according to the embodiment of the present invention, Fig. 2 is a side sectional view of the main part of the intake port of Fig. 1, and Fig. 3 is a line I-I of Fig. 1. FIG. 1... Cylinder head, 2... Intake port, 3... Intake valve, 4... Intake hole,
5...Protrusion, 6...Valve seat, A, B, C
...Inspiratory flow.

Claims (1)

[Scope of utility model registration request] A spiral intake port of a two-valve direct injection internal combustion engine, in which the spiral shape of the intake port connected to the intake hole 4 provided off the center of the cylinder is formed so as to wrap around the center of the cylinder and toward the exhaust valve side. , a substantially horizontal protrusion 5 for deflecting the intake air flow is provided on the side wall surface between the intake and exhaust valves directly above the valve seat 6 in the intake hole 4 so that its edge is substantially straight. The intake port of a direct injection internal combustion engine.