JPS6176757A - Air cleaner for vehicle engine - Google Patents

Abstract

PURPOSE:To reduce intake-air noise upon normal operation of an engine without lowering the engine performance in the high rotational speed range of the engine, by providing such an arrangement that the opening area of an air suction port is set to be large in the high rotational speed range of the engine while it is set to be small in the normal rotational speed range thereof. CONSTITUTION:A plate-like slide valve 9 incorporated in an air suction port 6 in an air-cleaner 4, is coupled to a movable member in a servo-motor 12 through an arm 11 rotatably supported to a fulcrum 10, and is moved laterally when the serve-motor 12 is driven, to change the opening area of the air suction port 6. The opening area of the port 6 is changed such that it becomes large in the high rotational speed range of the engine while it becomes small in the normal rotational speed range thereof.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to the structure of an air cleaner for an engine of a vehicle such as a motorcycle or an automobile, and particularly to the structure of an air intake port of the air cleaner.

[Prior art] In the engines of vehicles such as motorcycles and automobiles,
The air cleaner is configured to introduce air purified by an air cleaner into the combustion chamber through an intake hole as enodine supply air.

By the way, in conventional air cleaners of this type, the opening area of the air intake port is constant, and this opening area is mainly determined by the required air supply jlVc in the high rotation range, taking into account the entire engine output. At VC, intake noise is generated, but this noise is also influenced by the area of the air suction port of the air cleaner, and the larger the area, the louder the noise.

According to the inventor's test research, the causes of intake noise include: when the intake noise itself propagates to the outside, when the wall of the air cleaner resonates with the intake noise and generates chattering noise; 'Sound may pass through the walls of the air cleaner, producing transmitted sound, but the biggest factor is that the intake noise itself propagates to the outside, and this factor mainly affects the level of intake noise. found.

Therefore, as described above, by reducing the area of the air suction port, it is possible to suppress the propagation of intake noise to the outside and reduce intake noise.

However, in conventional air cleaners, the area of the air intake port is fixed, so this? If you try to reduce the total intake noise by setting it to a small value, there is a problem that the intake air is insufficient in the high rotation range and the engine performance deteriorates. The drawback is that it is impossible (or extremely difficult) to reduce the total intake noise at 3/4).

[Purpose of the invention]

An object of the present invention is to provide an air cleaner for a vehicle engine that can eliminate all of the drawbacks of the prior art and can completely reduce intake noise during regular operation without deteriorating engine performance in a high rotation range. [Structure of the invention] What is not invented is the opening area of the air suction port of the air cleaner? By making the LD variable, all of the above objectives are achieved.

That is, according to the present invention, the opening area of the air intake port is made variable from the engine speed 1/C so that it is sharp in the high engine speed range and relatively small in the normal engine speed range. An air cleaner for a vehicle engine is provided.

〔Example〕

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

1 and 2 show an air cleaner for a vehicle engine according to one embodiment.

In FIG. 1, a carburetor 3 is connected to an intake hole 2 of a cylinder 1 of a seven-cylinder head f ratio of a vehicle engine, and an air cleaner 4 is connected to an inlet of the carburetor 63.

The air cleaner 4 has an air suction port 6 and an air outlet lower T formed in a sealed case 5, an element (filtering member) 8 installed inside the case 5, and an air volume lower Tt formed in the carburetor 3 (or intake pipe). As shown by the arrow in FIG.

The air suction port 6Vc of the air cleaner 4 is provided with a plate-shaped slide valve 9 as shown in FIG.
is connected to the movable member of the servo motor 12,
By driving the servo motor 12, it can be moved left and right (in the direction of both arrows) and can be changed to the opening surface* of the air suction port 6.

The opening area of the air suction port 6 is set to vary depending on the engine speed so that it is large in the high speed range of the engine, and becomes relatively small in the normal speed range.

FIGS. 3 and 4 show all examples of this method of controlling the aperture area.

In FIGS. 3 and 4, the servo motor 12 is driven based on the operation of a tachometer 13. As shown in FIGS.

Therefore, in the case of an engine that achieves maximum cylinder output at approximately 550 ORPM, the full cut-off point is set at, for example, 3500 BPM, and the servo motor 12 is turned off as shown in Figure 3 in the normal use and low rotation ranges below the switching point. The opening area of the air suction port 6 is made small, and the servo motor 12t is turned on as shown in Fig. 4 in the high rotation range above the cutting point.
I control is performed to increase the opening area (in the illustrated example, the air intake hole 6 is fully opened).

In addition, the operation of the servo motor 12 is controlled by ON/OFF as described above.
In addition to the two-stage OFF switching, it is also possible to change the opening area to three or more stages depending on the engine speed, or to change the opening area continuously. Slide valve 9
Although 1r and 1r were conveniently used, this fL can also be structured to control the opening area using a slide valve that moves up and down.

Furthermore, in the illustrated structure, the rotation speed control @1 is performed by fully utilizing the tachometer, which directly corresponds to the engine rotation speed, but in some cases, the throttle opening or engine intake negative pressure, which approximately corresponds to the engine rotation speed, may be used. It is also possible to control the rotational speed by using the rotor and the like.

According to the embodiment described above, the opening area of the air suction port 6 of the air cleaner is controlled based on the engine speed, so that it is large in the high rotation range and small in the normal and low rotation range. Compared to a type with a constant opening area, it is possible to completely reduce the intake noise in the normal rotation range and low rotation range without causing a decrease in engine performance (output, etc.).

In addition, according to the noise regulations implemented in each country, the compliance of the engine is determined based on the noise level at a rotation speed (S rotation) that is a certain ratio (for example, 1/2) to the output rotation speed.
According to the above-described embodiment, it is possible to easily pass all noise regulations without causing any deterioration in engine performance, and therefore it is possible to easily provide a vehicle that does not generate noise pollution when driving on public roads or at night.

In conventional models with a fixed opening area, the air intake port was often designed to be smaller to prevent coughing noise, making concessions in terms of engine performance. According to the example, full engine performance can be extracted without the need for such concessions.

5 to 8 show main parts of an air cleaner for a vehicle engine according to another embodiment.

In this embodiment, the air suction hole 6 is entirely formed by a cylindrical portion 14 protruding from the airtight case 5 of the air cleaner, and a butterfly valve 15 is installed inside the cylindrical portion 14.
The opening degree of the yield butterfly valve 15 is controlled by a servo motor 12. The other structures are substantially the same as those shown in Figures 1 to 4, and in the low rotation range the state is as shown in Figures 5 and 6, and in the high rotation range as shown in Figures 7 and 8. become a state.

That is, in this embodiment, the entire butterfly valve 15 is used instead of the slide pulp 9 shown in FIGS. 1 to 4, so that the present embodiment has substantially the same light as the above-mentioned embodiment, and the other components are the same. works the same way. Although the illustrated butterfly valve 15 has a horizontal shaft arrangement, it may also have a vertical shaft or oblique arrangement.

Therefore, in this embodiment, the same operation and effect as in the case of the air cleaner explained with reference to FIGS. IJ f be able to do it immediately.

211: The air cleaner for a vehicle engine according to the invention can be widely applied regardless of the type or model of the engine, and can be applied to spark ignition, compression ignition, 2-cycle, 2-cycle, 4-cycle, or carburetor. First, it can be implemented in the same way in air cleaners for various types of (c) combustion engines.

In addition, a valve 9 that changes the entire opening area of the air suction port 6
．． As the drive device 15, not only the servo motor 12 as shown, but also other suitable drive devices can be conveniently used.

〔Effect of the invention〕

As is clear from the above explanation, according to the present invention, intake noise in the engine's normal rotation range can be reduced. Provided is an air cleaner for a vehicle engine that can easily and effectively reduce air pollution.

[Brief explanation of drawings]

FIG. 1 is a vertical cross-sectional view of an air cleaner for a vehicle engine according to a practical example VC of the present invention, and FIG. 2 is a line 1l-- in FIG. 1.
The front view as seen from II, FIGS. 3 and 4 illustrate the poor control of the opening area of the air suction port of the air cleaner shown in FIGS. FIG. 5 is a partial front view showing the state of the air suction port of an air cleaner according to another embodiment in a low rotation range;
Figure 6 is a vertical sectional view seen from Katsu - Vl in Figure 5, and Figure 7
The figure is a partial front view showing the state in the high rotation range of Figure 5, and Figure 8.
The figure is a vertical sectional view taken from tm-vm in FIG. 1... Vehicle engine, 4... Air cleaner, 6
...Air suction port, 9...Slide pulp, 12.
... Servo motor, 13... Tachometer, 15...
butterfly valve. Agent Patent Attorney Oon 1 Takeshi Figure 1 Figure 2 District: Lr) <D Weak Law District E To 0 Ambiguity

Claims (1)

[Claims] (1) An air cleaner for a vehicle engine, characterized in that the opening area of the air intake port is made variable depending on the engine speed so that it is large in the high engine speed range and relatively small in the normal engine speed range.