JPS5924851Y2 - Air supply path for internal combustion engines - Google Patents

Description

[Detailed explanation of the idea] The present invention relates to the structure of an air supply path for an internal combustion engine.

The cylinder of a reciprocating piston type internal combustion engine, especially a direct injection engine, is equipped with an air supply path for supplying combustion air, but this air supply path generates a strong swirling flow inside the cylinder and does not require sufficient charging efficiency. It is necessary to design the fuel in such a way that it can achieve maximum combustion efficiency.

The present invention relates to an improvement of a so-called spiral-type air supply path in which the air supply path winds around an intake valve shaft and flows into the cylinder via a swirling guide path section so as to generate a swirling air flow within the cylinder.

Various structures have been proposed for the spiral air supply passage, and one example is as shown in FIGS. A collision wall 4 on which the airflow collides is formed protruding from the side, and the inflowing airflow is rapidly directed downward toward the swirling guide path section 2, increasing the flow velocity of the air around the valve stem boss 5 to create a swirling airflow. Although the strength has been increased, it is still not sufficient and the filling efficiency is not high.

Therefore, the present inventors conducted intensive studies and completed the present invention.

That is, the present invention provides an air supply passage for an internal combustion engine configured to cause airflow flowing in from the entrance of the introduction passage to flow into the cylinder as a swirling airflow around a valve shaft through a swirling guide passage. is bent at a substantially right angle so as to join in the tangential direction of the turning guide path portion, and a convex guide ridge protruding downward toward the introduction path portion is provided on the earthen wall of the turning guide path portion, and The present invention is characterized in that a collision wall is provided extending from the bent portion of the introduction path portion to the boss portion of the valve shaft.

Hereinafter, one embodiment of the present invention will be described based on the drawings.

3 is a plan sectional view showing the configuration of the air supply path of the present invention, FIG. 4 is a side sectional view thereof, and FIG. 5 is a partial sectional view taken along the arrow line A--A in FIG. 3.

In the figure, 6 is an introduction passage, 7 is a turning guide passage, 8 is a valve shaft guide boss hanging down to an appropriate length from the ceiling wall of the turning guide passage 7, 9 is an intake valve, and 10 is a valve shaft. be.

As shown in FIG. 3, reference numeral 11 is a collision wall connected to the boss 8 from the bent side wall of the introduction passage 6 so that the incoming air collides with it and is directed toward the entrance of the turning guide step. 8, and is configured so that the air drawn in around the valve stem collides with the back surface of the valve stem and is directed downward toward the intake port 12.

Reference numeral 13 denotes a convex guide ridge provided on the earthen wall transitioning from the introduction path section 6 to the turning guide path section 7, which is smoothly raised with an appropriate radius of curvature R to throttle the incoming air downward and increase the flow velocity. It functions to direct the direction toward the turning guide path.

Note that in the figure, arrows indicate the inflow direction of airflow.

The air flowing into the introduction passage 6 changes its direction almost at right angles along the collision wall 11 at the bending part of the introduction passage 6, and then flows down along the convex guide ridge 13, and most of the air flows down along the convex guide ridge 13. flows into the cylinder from the intake port 12 while forming a first swirl, and the remaining air swirls along the swirling guide path 7 and rapidly flows down along the back surface of the collision wall 11 to form the first swirl. It passes under the first swirl and flows into the cylinder as a second swirl, and the combination of these two swirls creates a powerful swirl inside the cylinder, which significantly improves the filling efficiency. .

As described above, the air supply path for an internal combustion engine of the present invention has the introduction path section 6 bent at a substantially right angle so as to join in the tangential direction of the turning guide path section 7. Because the wall is provided with a convex guide protuberance 13 protruding downward near the introduction passage portion, and a collision wall 11 is provided extending from the bent portion of the introduction passage portion 6 to the boss portion 8 of the valve stem. A strong swirl is generated in the cylinder by the combination of the first and second swirls, and the filling efficiency is also significantly improved.

[Brief explanation of drawings]

Fig. 1 is a plan sectional view showing an example of a conventional air supply passage, Fig. 2 is a side sectional view thereof, Fig. 3 is a plan sectional view showing the configuration of the air supply passage of the present invention, and Fig. 4 is its side. 5 is a partial sectional view of the collision wall portion. DESCRIPTION OF SYMBOLS 1...Introduction path section, 2...Turning guide path section, 3...Top wall, 4...Collision wall, 5...
...Valve stem boss, 6...Introduction passage, 7...
...Swivel guide path section, 8...Valve stem guide boss, 9...Intake valve, 10...Valve stem, 11
...Collision wall, 12...Intake port, 13.
...Convex guide ridge.

Claims (1)

[Scope of utility model registration request] In an air supply passage for an internal combustion engine configured such that the airflow flowing in from the inlet of the introduction passage part 6 is made into a swirling airflow around the valve shaft by the swirling guide passage part 7 and flows into the cylinder, the introduction passage part 6 is A convex guide ridge 13 is provided on the soil wall of the turning guide path 7, which is bent at a substantially right angle so as to join in the connection direction of the turning guide path 7, and protrudes downward toward the introduction path 6. , and a collision wall 11 extending from the bending part of the introduction passage part 6 to the boss part 8 of the valve shaft is provided.