JPH07208185A - Swirl control valve of engine - Google Patents

Abstract

PURPOSE:To prevent the reduction of the engine output in the whole operation area, as well as to reduce an increase in the suction resistance at the full opening time of a swirl control valve when the swirl controllable scope is widen, by increasing the thickness of the valve plate part at the side not providing an opening for generating a swirl, at one side of a valve shaft. CONSTITUTION:A valve plate 1 is installed to a main shaft 8 at the position eccentric to the thick side from its center line, the valve plate part 4 at the thin side having an opening 5 is opened widely in the opening scope where the valve plate part 2 at the chick side blocks a conduct 11, so as to secure the suction air amount while generating a swirl, and the projected area of the valve plate 11 at the full opening condition is made smaller, so as to secure the suction air amount in the high load operation area.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention is installed in an intake passage of an engine and is closed in a low / medium speed range to generate swirl in a combustion chamber. It relates to a swirl control valve that works to ensure that.

[0002]

2. Description of the Related Art Combustion of a lean air-fuel mixture in an automobile engine is one of the effective means for fuel economy and exhaust emission control. It is a well-known technique that it is possible to burn the lean air-fuel mixture without causing misfire by generating it, and for that reason, it is possible to significantly increase the exhaust gas recirculation amount and improve the fuel economy. .

As is widely known, as a means for generating a swirl in the fuel chamber of an engine, each branch pipe of the intake manifold is divided into two, and a control valve is installed in one of the branch pipes, and the other is provided when the valve is closed. A swirl is generated by the flowing air, and a control valve is installed without dividing the branch pipe into two, and when the valve is closed, the swirl is generated by the air passing through the opening such as the cutout of the valve plate. There are some that were made to let you. Further, the control valve is normally a two-position control of fully closed and fully opened by a diaphragm which is displaced by the intake manifold negative pressure as represented by JP-A-54-99826. In some cases, stepping motors that operate in accordance with this may be used for stepless position control.

If the swirl generating means has a structure in which a control valve having an opening in a valve plate is driven by a diaphragm type actuator, there is an advantage that the structure is simple and can be provided at a low cost. .

However, since the control valve is a butterfly valve having a flat plate, the swirl sharply decreases when opening the valve when two-position control is performed by a diaphragm type actuator, and swirl control with respect to the intake air amount. The problem is that the possible range is extremely narrow. Therefore, as shown in FIG. 4, one valve plate portion 53 sandwiching the valve shaft 51 on the center line of the valve plate 52 is provided on the other valve plate portion 5 provided with the opening 57.
Those having a thickness greater than 5 are being developed.

That is, the outer peripheral edge 54, which is the maximum wall thickness portion of the valve wall portion 53 on the thick wall side, extends from the fully closed position to a certain opening degree.
8 is almost in contact with the pipe wall 59, while the outer peripheral edge 56 of the valve plate portion 55 on the thin wall side starts to open at the same time as the pipe wall 59.
By moving away from, the air is allowed to pass only through the gap and the opening 57 to expand the swirl controllable range.

However, if the wall thickness of the valve plate portion 53 on the thick wall side is increased in order to perform swirl control over a wide range of low / medium speed rotation range, the intake resistance at full opening increases and high load operation is performed. This causes the inconvenience that the engine output in the range decreases. In addition, since the valve shaft 51 is arranged on the center line of the valve plate 52, the valve plate portion 53 at the time of fully closing and at the side of the thick wall 53
There is a problem that the opening area difference from the time when the valve starts to separate from the pipe wall 59 is small, and therefore the intake air amount during this time does not increase in accordance with the rotation angle of the valve plate 52, and the engine output tends to be insufficient.

[0008]

The problem to be solved by the present invention is to widen the swirl controllable range by replacing the flat valve plate with the valve shaft sandwiching the valve shaft and thickening the valve plate opposite to the opening. The swirl control valve, which has been measured, increases the intake resistance when fully opened and decreases the engine output in the high load operation range.In addition to this, the engine output is increased until the valve plate part on the thick side begins to open. It is easy to run out.

[0009]

The present invention has a swirl control valve in which one valve plate portion sandwiching the valve shaft of the valve plate is thicker than the other valve plate portion provided with an opening. It is an object of the present invention to solve the above problems, reduce the increase in intake resistance at the time of full opening, and supply the required air amount of the engine from the beginning of opening to full opening. In order to achieve such an object, the present invention has a structure in which the valve plate is attached to the valve shaft at a location eccentric to the thicker side of the center line.

[0010]

When the air is fully closed, the air passes around the valve plate with the opening as the main passage, and swirls are generated in the combustion chamber. When valve opening is started, the valve plate part on the thin wall side separates from the pipe wall of the conduit to increase the amount of intake air, but the air flow is biased while the valve plate part on the thick wall side is in contact with the pipe wall. The swirl does not decrease sharply. In addition, since the valve shaft is eccentric to the thicker side than the center of the valve plate, even if the valve plate on the thicker side is thinned, it remains closed until it is fully opened from the fully closed position, while the thin side Since the valve plate portion is far away from the pipe wall, the swirl is continuously generated and the intake air amount is increased corresponding to the rotation angle of the valve plate. Further, since the maximum wall thickness can be made small, the increase in intake resistance at the time of full opening can be made small to supply the required air amount of the engine.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described with reference to the drawings. A valve plate 1 is substantially oval and is attached to a valve shaft 8 in its longitudinal direction. One valve plate portion 2 of the two valve plate portions 2 and 4 sandwiching the valve shaft 8 is formed to have a triangular shape in cross section which gradually becomes thicker toward the outer peripheral edge 3, and the other valve plate portion 2 is formed. 4 is formed in a thin plate shape having a uniform thickness.

The valve shaft 8 is eccentric toward the valve plate portion 2 on the thicker side than the longitudinal centerline of the valve plate 1, and therefore the two valve plate portions 2 and 4 have a short length in the thin meridian direction. The valve plate portion 4 on the side is larger. Further, an opening 5 formed by a notch is provided on one side of the thin valve plate portion 4.

In this embodiment having such a structure, as shown in FIG. 1, the center line of the valve plate 1 in the short meridian direction is the center line A- of the conduit 11.
The state at right angles to A is the fully closed position, and the valve plate portion 2 on the thick side is widened rearward in the valve opening rotation direction. At this time, the air has the opening 5 as a main passage and the valve plate 1
Swirl is generated in the combustion chamber as it passes around.

When the opening of the valve is started, as shown in (1) of FIG. 3, while the valve plate portion 2 on the thick wall side is rotated by an angle corresponding to the spread angle θ, the outer peripheral edge which is the maximum wall thickness portion. Since 3 is an arcuate surface centered on the center of rotation, it is in close contact with the pipe wall 12 and maintains a closed state. On the other hand, the valve plate portion 4 on the thin side
The outer peripheral edge 6 of the is largely separated from the pipe wall 12 at the same rotation angle as compared with the valve shaft 8 arranged at the center, and the intake air amount is increased corresponding to the rotation angle to secure the required air amount of the engine. However, since the valve plate portion 2 on the thick side is in contact with the pipe wall 12, the air flows unevenly in the direction in which the opening 5 is provided, and the swirl continues to be generated without being rapidly reduced.

When rotated from the fully closed position by an angle of θ or more, as shown in FIG.
As shown in (2), the outer peripheral edge 3 of the valve plate portion 2 on the thick wall side is separated from the pipe wall 12 so that air can freely flow from this gap, and the intake air amount further increases and the swirl It decreases and disappears.

FIG. 3 (3) shows the fully open position, and even if the maximum wall thickness of the valve plate portion 2 on the thick wall side is thinned, it starts to open, so that the rotation angle range for maintaining the closed state can be widened. While increasing the swirl controllable range, it is possible to reduce the projected area of the valve plate 1 at the time of full opening and suppress the increase in intake resistance to a low level to secure the required air amount in the high load operation range.

The valve plate 1 may have a triangular cross section as a whole, but it is advantageous in terms of material cost and weight to make the thick wall side triangular as shown in the figure. Needless to say, the opening 5 may be a hole instead of the notch.

[0018]

As is apparent from the above, according to the present invention in which the valve plate is attached to the valve shaft at a location eccentric to the thicker side than the center line, the swirl can be achieved even if the thicker valve plate portion is thinned. The controllable range can be widened and the intake air amount can be reduced by opening the valve plate part on the thin wall side largely without the inconvenience of rapidly reducing the swirl initially when the valve is opened. It can be increased corresponding to the rotation angle. Also, by making the valve plate part on the thick side thin,
When the engine is fully opened, the required air amount in the high load operation range is ensured and the output of the engine is not reduced. By these, the required air amount can be supplied over the entire operation range of the engine to obtain the required engine output.

[Brief description of drawings]

FIG. 1 is a side view showing an embodiment of the present invention.

FIG. 2 is a front view of FIG.

FIG. 3 is a side view for explaining the operation of the embodiment shown in FIG.

FIG. 4 is a side view of a conventional example.

[Explanation of symbols]

1 valve plate, 2, 4 valve plate part, 3 outer peripheral edge, 5 opening part, 8 valve shaft,

Claims (1)

[Claims] 1. A swirl control valve for an engine, wherein one valve plate portion sandwiching a valve shaft of the valve plate is thicker than the other valve plate portion having an opening, and the valve plate is the center of the swirl control valve. A swirl control valve characterized in that it is mounted on the valve shaft at an eccentric position on the thicker side than the line.