KR20030039476A - Resonator apparatus - Google Patents

Abstract

PURPOSE: A resonator for offsetting intake noise of a surge tank is provided to change noise offset frequency depending on working state of an engine. CONSTITUTION: A resonator(4) is connected with a surge tank(1) through two neck parts(5,6). One of the neck parts is a low speed channel(8) with smaller sectional area(A1) and longer length(L1). The other of the neck parts is a high speed channel(9) with larger sectional area(A2) and shorter length(L2). A valve(10) rotates centering on a hinge axis(11) to selectively open and close the channels and rotated by an actuator. The lengths and sectional areas of the neck parts of the resonator are designed correspondingly with characteristic operation area of an engine, for example, low speed of 2000RPM and high speed of 3500RPM. An electronic control unit detects through an RPM sensor when the engine runs at low speed, and controls an actuator so that the valve cuts off the high speed channel and opens the low speed channel. The resonator and the surge tank are connected through the low speed channel thereby to damp noise frequency corresponding with the RPM. The electronic control unit controls the actuator when the engine runs at high speed so that the valve cuts off the low speed channel and opens the high speed channel. The resonator and the surge tank are connected through the high speed channel to damp noise frequency corresponding with the RPM.

Description

Resonator apparatus for reducing the intake noise of surge tank

The present invention relates to a resonator device for reducing the intake and noise of a surge tank.

When the engine is driven and intake negative pressure is generated, outside air is introduced through the intake system.

This intake air is supplied to each cylinder through the intake manifold 21 in the surge tank 20 as shown in FIG.

By the way, the air flowing into the surge tank 20 changes direction and intakes into the combustion chamber through the intake manifold 21 to impinge the intake noise in the process of forming an eddy current while hitting the inner wall surface of the surge tank 20. Done.

For this reason, as shown in order to reduce intake noise generated in the surge tank 20, the surge tank 20 is equipped with a resonator 22 having a certain volume to attenuate the noise.

The resonator 22 has a neck 23 having a constant cross-sectional area A and a length L as a resonator, and the noise attenuation frequency f can be obtained from these conditions.

Noise Reduction Frequency (f)

only,

A: cross-sectional area of the neck (cm 2)

V: Volume of Resonator (cm 3)

L: Neck length (cm)

C: sound speed

It is represented by the formula

On the other hand, four-cylinder engines have two explosions per engine revolution, so the engine frequency by rpm

Since the frequency of each engine rpm is given as shown in Table 1.

Table 1. Application Examples of Engine Frequency by RPM

For example, if the driving condition is 3000rpm

If the engine is designed to run at constant speed at 3000 rpm, the target noise attenuation frequency f is 100 Hz, the volume V of the resonator 22 and the cross-sectional area A and length L of the neck 23. Will be designed).

However, according to the conventional structure described above, by connecting the resonator 22 of a certain specification (V, A, L) to the surge tank 20 to induce a noise attenuation effect only at a specific rpm, the noise attenuation effect is high or low speed. There is a problem that it is difficult to attenuate a wide range of noise limited to the driving area.

In addition, in the related art, it is difficult to avoid a phenomenon in which the torque of the engine drops in a certain rpm section, because it is known that there is a limit in the synchronization with the tuning frequency by the regulator of a certain specification.

Accordingly, the present invention has been proposed in view of the above point, and its object is to have a specification in which the noise attenuation frequency is changed according to the operating conditions of the engine, and the intake noise of the surge tank which can prevent the engine torque drop at a specific rpm. The present invention provides a damping resonator device.

In order to achieve the above object, the present invention provides a resonator device having a predetermined volume which is connected to a surge tank into which air to be distributed to each cylinder is introduced through an intake manifold to reduce intake noise.

The resonator and the surge tank are connected through a low-speed and high-speed neck having different cross-sectional areas and neck lengths, and have a valve for selectively opening and closing the low-speed neck and the high-speed neck in response to operating conditions. It is characterized by.

1 is a view showing an operating state in a low speed operation of the resonator device for the intake noise reduction of the surge tank according to the present invention

2 is a view showing an operating state of the in-phase resonator device in high speed operation;

3 is a control block diagram of the present invention;

4 is a prior art

※ Explanation of codes for main parts of drawing

1: Surge tank 2: Intake manifold

3: inlet port 4: surge tank

5: neck for low speed 6: neck for high speed

8: low speed passage 9: high speed passage

10 valve 11 hinge shaft

12: actuator 13: electronic control device

14 rpm sensor A ₁ , A ₂ neck cross-sectional area

L ₁ , L ₂ : neck length

Hereinafter, the configuration of the present invention will be described with reference to the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a view showing an operating state during engine low speed operation of a resonator device for intake noise reduction of a surge tank according to the present invention, and Fig. 2 is a view showing an operating state during engine high speed operation of an in-phase resonator device. 3 is a control block diagram of the present invention.

In the drawing, reference numeral 1 denotes a surge tank, and reference numeral 2 denotes an intake manifold in which air introduced into the surge tank 1 from the throttle body side through the inlet port 3 changes direction and distributes air to each intake port of the cylinder head. .

The intake manifold 2 is formed in a curved tube as shown in the drawing, and a resonator 4 having a predetermined volume V is provided using a space formed inside the bent portion.

The resonator 4 is connected to communicate with the surge tank 1 through two necks 5 and 6, but the specifications of the two necks 5 and 6 are different.

Among the two necks 5 and 6, the neck 5 having a small cross-sectional area A ₁ and a long length L ₁ is a low-speed passage 8, a large cross-sectional area A ₂ , and a length L. ₂ ) The short neck 6 is a high speed passage 9, at which branching points of the low speed and high speed passages 8 and 9 are alternatively connected to the passages 8 and 9 by rotational operation. The valve 10 to be opened and closed is installed to rotate about the hinge shaft 11, and the valve 10 is rotated by an actuator 12 of a step motor type.

Hereinafter, the operation of the present invention will be described.

The cross-sectional area (A ₁ ) (A ₂ ) and length (L ₁ ) (L ₂ ) of the neck (5) and (6) of the resonator (4) are designed for the specific operating area of the engine, e.g. a low speed of 2000 rpm and a 3500 rpm It is designed for high speed operation.

Therefore, when the engine is driven at a low speed of about 2000 rpm, the electronic controller 13 detects this from the rpm sensor 14 and drives the actuator 12 so that the valve 10 blocks the high speed passage 9 and the low speed passage 8 ) To open.

Accordingly, the resonator 4 and the surge tank 1 communicate with each other through the low speed passage 8 to attenuate the noise frequency corresponding to the operation rpm.

On the other hand, when the engine enters the high speed operation (3500 rpm), the electronic control device 13 drives and controls the actuator 12 by the signal detected from the rpm sensor 14 so that the valve 10 opens the passage 8 for the low speed. It switches off to block and open the high speed passage 9.

Accordingly, the resonator 4 is communicated through the surge tank 1 and the high-speed passage 9 to attenuate the noise frequency under the rpm condition.

The present invention as described above is connected to the surge tank through the neck of the two high-speed and low-speed passages having a cross-sectional area and length in accordance with the different operating conditions to each operating condition, each passage is adapted to the operating conditions By installing an open valve at the branch connection point, it is possible to reduce the intake noise by tuning to two kinds of noisy operating conditions, and to improve the engine performance by reducing the torque drop at a specific rpm. This can greatly increase the utility of the resonator.

Claims (4)

A resonator device having a constant volume connected to a surge tank into which air to be decomposed into each cylinder through an intake manifold to attenuate intake noise, The resonator and the surge tank are connected through a low-speed and high-speed neck having different cross-sectional areas and neck lengths, and have a valve for selectively opening and closing the low-speed neck and the high-speed neck in response to operating conditions. Resonator device for reducing the intake noise of the surge tank, characterized in that. The method of claim 1, The valve is a resonator device for reducing the intake and noise of the surge tank, characterized in that the rotation opening and closing operation by an actuator that is a step motor. The method of claim 2, The electronic control device controls the valve to close the low speed passage during high speed operation of the engine based on the information detected from the rpm sensor, and controls the operation to close the high speed passage during low speed operation of the engine. Resonator device for reducing the intake noise of the surge tank, characterized in that. The method of claim 1, The resonator is a resonator device for reducing the intake noise of the surge tank, characterized in that formed using the empty space formed inside the bent intake manifold.