JPH0410341Y2 - - Google Patents

Description

[Detailed Description of the Invention] Industrial Application Field The present invention relates to a variable intake swirl type intake port device used in a twin intake port type internal combustion engine, and particularly to a Siyamese type intake port device.

BACKGROUND OF THE INVENTION A Siyamize-type intake port device for an internal combustion engine used in a vehicle such as an automobile includes a helical passage in which one of two intake ports is rotated around an axis relative to an open end of a combustion chamber by a partition wall; a bypass passage that is located closer to the other intake port than the helical passage and directly communicates with the end of the swirling part of the helical passage; An intake port device that is provided with an intake control valve that selectively blocks communication and closes the inlet portions of the other intake port and the bypass passage has already been proposed. This is shown in Publication No. 92733.

In addition, each cylinder has one intake inlet section, which branches into two intake ports in the middle, each of which opens toward the combustion chamber, and each of the two intake ports has a separate intake port. The intake port is configured to be opened and closed by a valve, and one of the two intake ports has a bulging wall portion that hangs down halfway in the intake port height direction from the upper wall of the port. A helical passage that is turned around the axis of the opening end relative to the combustion chamber by the bulging wall portion, and a straight line that is located on the side of the other intake port compared to the helical passage and directly communicates with the end of the turning part of the helical passage. and a bypass passage, and the bulging wall portion extends toward the intake inlet side, and extends into the bypass passage near the end on the intake inlet side and the other intake port side. A Siyamise type intake port device provided with an intake control valve which selectively closes a portion has been proposed in Japanese Patent Application No. 61-39550 by the same applicant as the present applicant.

In the above-mentioned intake port device, when the intake control valve is closed, most of the intake air flows into the combustion chamber of the internal combustion engine through the helical passage of the one intake port, thereby creating an intake swirl inside the combustion chamber. This increases the lean air-fuel ratio limit of the combustible mixture, whereas when the intake control valve is open, in addition to the helical passage, the other intake port, and also the bypass passage of the one intake port. Even after passing through the combustion chamber, the intake air flows into the combustion chamber, which allows intake air to be carried out with high charging efficiency.

Problems to be Solved by the Invention In the above-mentioned intake port device, the bulging wall is provided only halfway in the height direction of the intake port from the upper wall of the port. Compared to a continuous, complete partition, the intake resistance is lower and the charging efficiency is improved, but the degree of intake swirl is reduced and the lean burn limit is not extended.

In view of the above-mentioned problems, the present invention aims to provide an improved Siyamize-type intake port device that enables better lean burn operation than conventional ones and minimizes the decrease in charging efficiency. The purpose is

Means for Solving the Problems According to the present invention, each cylinder has one intake port, which branches into two intake ports midway, and each cylinder has one intake port. In a Saiyamise-type intake port device for an internal combustion engine, which opens toward a combustion chamber and is configured such that the two intake ports are opened and closed by individual intake valves,
One of the two intake ports has a bulging wall that hangs down halfway in the height direction of the intake port from the upper wall of the port, and the bulging wall provides a connection to the combustion chamber. The helical passage is divided into a helical passage that turns around the axis of the opening end, and a linear bypass passage that is located on the side of the other intake port compared to the helical passage and directly communicates with the end of the turning part of the helical passage, The bulging wall extends toward the intake inlet, and intake control selectively closes the bypass passage near the end on the intake inlet and the other intake port. In a Siyamize-type intake port device for an internal combustion engine that is provided with a valve, the bulging wall portion may be such that the side of the bypass passage hangs down more in the intake port height direction than the side of the helical passage. This is achieved by a Saiyamise-type intake port device featuring:

Effects and Effects of the Invention According to the above-described configuration, only the bypass passage side of the bulging wall part hangs down significantly, and as a result,
As the degree of occurrence of intake swirl increases, the flow resistance given by the helical passage to the flow of intake air is reduced or its increase is avoided, and the intake swirl is strengthened while minimizing the reduction in filling efficiency.

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

1 to 3 show one embodiment of a Siyamize-type intake port device for an internal combustion engine according to the present invention. In these figures, reference numeral 10 indicates a cylinder head of an internal combustion engine, in which a Siyamese-type intake port 14 is provided for each cylinder 12. The Saiyamise-type intake port 14 has one intake inlet portion 16 for each cylinder 12, and a partition wall 36 is provided to connect the port upper wall 32 and the port lower wall 34 to each other from the middle. It branches into ports 18 and 20, each of which opens toward a combustion chamber 22, and whose respective open ends 24 and 26 are opened and closed by separate intake valves 28 and 30, respectively. There is.

The intake port 18 has a bulging wall portion 3 that hangs down halfway in the intake port height direction from the port upper wall 32.
8 is provided, and this bulging wall portion 38 surrounds the stem guide 29 of the intake valve 28 at one end,
It extends from this point toward the intake inlet portion 16 in a tapered shape, divides the intake port 18 into two, is located on the opposite side from the intake port 20, and extends around the axis of the opening end 24 relative to the combustion chamber 22. In other words, the helical passage 40 that has turned around the stem guide 29 is located on the side of the intake port 20 compared to the helical passage 40, and is directly connected to the end of the turning part of the helical passage 40 from the branching part between the intake ports 18 and 20. It is divided into a linear bypass passage 42 that communicates with the passageway.

Unlike the partition wall 36, the bulging wall portion 38 is not connected to the port lower wall 34, and defines a gap 44 between the port lower wall 34 and the bypass passage 42 throughout. The side of the helical passage 40 hangs down more in the height direction of the intake port than the side of the helical passage 40. That is, the lower end of the bulging wall 38 is stepped, and the port lower wall 34 is located on the bypass passage 42 side.
It has an auxiliary bulging wall portion 41 that is closer to it.
The auxiliary bulging wall portion 41 is connected to the intake inlet portion 1 of the bulging wall portion 38.
The width becomes wider from the end 41a on the 6 side toward the stem guide 29, and at the end 41b on the stem guide 29 side, the outer circumference of the stem portion of the intake valve 28 on the helical passage 40 side becomes wider. It has spread to the corresponding position.

An intake control valve 46 is provided on the intake port 20 side of the bulging wall portion 38 . The intake control valve 46 is
When the plate-shaped valve element 48 is in the closed position as shown in FIGS. 1 and 2, the side of the bulging wall 38 facing the intake port 20, that is, the intake port 20 and the bypass passage The entrance portion of 42 is closed. The intake control valve 46 is opened and closed by a control device with a general structure (not shown), and is basically closed when the internal combustion engine is operating at a low load, and when the internal combustion engine is operated at a high load. The valves sometimes open.

According to the configuration described above, when the internal combustion engine is operated at a low load and the intake control valve 46 is closed, most of the intake air is guided by the bulging wall 38 and flows through the helical passage 40 into the combustion chamber 22. The air flows into the combustion chamber 22, creating an intake swirl around its axis. Furthermore, since the auxiliary bulging wall part 41 is provided, even if the intake air is guided by the auxiliary bulging wall part 41 in addition to the bulging wall part 38, it still flows into the combustion chamber 22 through the helical passage 40, and the intake air Reverse entrainment of intake air around the stem of valve 28 is reduced, which increases the likelihood of intake swirl.

A portion of the intake air is located below the bulging wall 38, that is, in the gap 4.
4 to the side of the bypass passage 42 and the intake port 20, so that even if the intake control valve 46 is closed, a portion of the intake air flows into the combustion chamber 22 from the bypass passage 42 and the intake port 20. This ensures that the spark plug 2 is located in the central region of the combustion chamber 22.
The air-fuel mixture with an average air-fuel ratio is now stably supplied to the part where No. 3 is installed, and the helical passage 40
Even if the fuel in the air-fuel mixture that has flowed into the combustion chamber 22 is pushed toward the side periphery of the combustion chamber 22 by the centrifugal action caused by the intake swirl in the combustion chamber 22, the spark plug 23 does not remain in the area where the spark plug 23 is disposed. The air-fuel mixture with the air-fuel ratio required for ignition is stably supplied, the ignition of the air-fuel mixture is reliably performed by the spark plug 23, and inter-cycle torque fluctuations due to ignition failure are reduced, and idle stability is improved. You will start to improve. When the air-fuel mixture is ignited by the spark plug 23, a helical passage 40 is formed in the combustion chamber 22.
Due to the relatively strong intake swirl caused by the mixed air-fuel mixture, the flame propagates along with the flow of intake air, which increases the apparent flame propagation speed and causes so-called rapid combustion. This allows for better operation with a lean mixture.

During high-load operation of the internal combustion engine, the intake control valve 46 is opened, so that intake air flows into the combustion chamber 22 from the helical passage 40, the intake port 20, and even the bypass passage 42. This allows intake to be carried out with high charging efficiency while taking advantage of the inherent advantages of the twin intake port type intake port, thereby improving output torque especially during full throttle operation.

Further, the bulging wall portion 38 that divides the intake port 18 into a helical passage 40 and a bypass passage 42 has a gap 44 between it and the port lower wall 34.
4, a helical passage 40 is formed in the lower port region.
The bypass passage 42 and the bypass passage 42 communicate with each other to provide a relatively wide passage, and furthermore, the auxiliary bulging wall portion 41 has the minimum width necessary to strengthen the intake swirl. The degree to which this reduces the filling efficiency is small, and deterioration of the filling efficiency is avoided.

Although the present invention has been described in detail with respect to specific embodiments above, the present invention is not limited thereto, and various embodiments are possible within the scope of the present invention. It will be clear to those skilled in the art.

[Brief explanation of the drawing]

FIG. 1 is a bottom cross-sectional view showing one embodiment of the Siyamiz-type intake port device for an internal combustion engine according to the present invention, and FIG. 2 is a Siyamiz-type intake port for the internal combustion engine according to the present invention shown in FIG. 1. A vertical cross-sectional view of the device, FIG. 3 is a cross-sectional view taken along the line - in FIG. 10...Cylinder head, 12...Cylinder, 14
...Siyamise type intake port, 16...Intake inlet portion, 18, 20...Intake port, 22...Combustion chamber, 23...Spark plug, 24, 26...Open end, 28...Intake valve, 29... ...Stem guide, 3
0... Intake valve, 32... Port upper wall, 34... Port lower wall, 36... Partition wall, 37... End, 38...
...Bulging wall portion, 40...Helical passage, 41...Auxiliary swelling wall portion, 42...Bypass passage, 44...Gap, 46...Intake control valve, 48...Valve element.

Claims (1)

[Scope of utility model registration request] Each cylinder has one intake inlet section, which branches into two intake ports midway, each of which opens toward the combustion chamber, and each of the two intake ports is operated by an individual intake valve. The intake port is configured to be opened and closed, and one of the two intake ports has a bulging wall portion that hangs down halfway in the height direction of the intake port from the upper wall of the port. a helical passage turned around the axis of an opening end relative to the combustion chamber by a protruding wall portion; and a linear bypass that is located on the side of the other intake port compared to the helical passage and directly communicates with the end of the turning part of the helical passage. The bulging wall portion extends toward the intake port side, and the bulging wall portion extends toward the side of the bypass passage and the other intake port near the end on the intake port side. In a Siyamese-type intake port device for an internal combustion engine that is provided with an intake control valve that selectively closes, the bulging wall portion has a side on the bypass passage that is closer to the height of the intake port than a side on the helical passage. A Saiyamise-type intake port device characterized by a large droop.