JPH04301174A - Intake device for engine - Google Patents

Abstract

PURPOSE:To secure the resonance work, and while restrict increase of the intake resistance and the peeling noise at the time of installation of a resonator through an opening part formed in an intake passage in the upstream of a throttle valve of an engine. CONSTITUTION:An opening port 23 for intake 20 communicated with a resonator 21 is provided near the upstream side of a throttle valve 15 in the direction crossing a throttle shaft 15a of that throttle valve 15 at a right angle at a position of the side where the throttle valve 15 is opened toward the upstream side in response to angle of the described throttle valve 15.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an engine intake system in which a resonator is provided in an intake passage to cause pressure waves or sound waves to resonate.

0002

[Prior Art] Conventionally, as an engine intake device,
For example, a technique in which a resonator having a predetermined volume is disposed in the intake passage in order to cause sound waves or pressure waves acting on the intake passage to resonate in order to muffle sound or increase torque is disclosed in Japanese Utility Model Application No. 1986- It is publicly known as seen in Japanese Patent No. 185056.

0003

[Problems to be Solved by the Invention] However, when a resonator is installed in the intake passage as described above, when trying to obtain a resonance effect with respect to pressure waves or sound waves generated downstream of the throttle valve. Normally, the above resonator is placed downstream of the throttle valve so that pressure waves etc. can directly act on it, but if it is placed downstream, the intake negative pressure will act on it, making the seal structure complicated and rigid. Furthermore, there are problems in that the intake resistance increases and the separation noise increases as the intake flow rate increases at the opening from the intake passage to the resonator.

[0004] Furthermore, when a resonator is disposed in the intake passage upstream of the throttle valve, pressure waves generated downstream of the throttle valve are effectively introduced to ensure a resonant effect. Even when it is disposed on the above side, there are similar problems in that the intake resistance increases and the peeling noise increases as the intake flow velocity increases at the opening.

[0005] In view of the above circumstances, the present invention provides an engine intake air intake system in which a resonator is disposed in the intake passage upstream of the throttle valve while ensuring a resonance effect, and an increase in intake resistance and separation noise is suppressed. The purpose is to provide a device.

[0006]

[Means for Solving the Problems] In order to achieve the above object, the intake device of the present invention communicates with a resonator having a predetermined volume through an opening formed in an intake passage. The opening of the intake passage is located near the upstream side of the throttle valve, in a direction perpendicular to the throttle shaft of the throttle valve, and on the side where the throttle valve opens upstream in response to rotation of the throttle valve. It is configured by being installed at a certain location.

[0007] Furthermore, the distance L between the center of the opening of the resonator and the throttle shaft is the bore diameter D of the throttle valve portion.
It is preferable to set it in the range of D/2≦L≦2D.

[0008]

[Operation and Effect] In the engine intake system as described above, by connecting the resonator to the intake passage upstream of the throttle valve, large intake negative pressure does not act, and the connection part from the intake passage to the resonator is The seal structure can be easily configured, and by opening near the upstream side of the throttle valve, pressure waves or sound waves on the downstream side are well introduced when the throttle valve opens, and a sufficient resonance effect is achieved. As a result, the desired torque increase or noise reduction effect can be ensured.

Furthermore, by forming the opening at the farthest position from the throttle shaft in the direction perpendicular to the throttle shaft of the throttle valve, when the throttle valve opens, the opening to the resonator is located at the part with the largest opening amount. In addition, the introduction of pressure waves downstream of the throttle valve is improved, and the resonance effect is increased. Moreover, since the throttle valve is rotated to open toward the upstream side, when the throttle valve is opened, the intake air flows intensively along the diagonal throttle valve in the part that opens downstream. While the intake flow velocity becomes high, the intake flow velocity near the opening on the opposite side becomes low, and it is possible to reduce the increase in intake resistance and the generation of separation noise due to the occurrence of intake air turbulence at this opening.

[0010] If the distance L between the center of the opening of the resonator and the throttle shaft is set in the range D/2≦L≦2D with respect to the bore diameter D of the throttle valve part, the opening will be connected to the throttle valve. When the throttle valve is closer than D/2, the pressure on the downstream side acting on the opening changes greatly in response to changes in the opening of the throttle valve, which is inappropriate. This is preferable in that an appropriate connection state can be achieved, since the introduction of side pressure waves and the like is reduced, making it impossible to obtain a sufficient resonance effect.

[0011]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Examples of the present invention will be described below with reference to the drawings. FIG. 1 shows a plan view of the overall configuration of an engine intake system according to this embodiment.

The air intake device 10 has an air introduction duct 11 at the upstream end, an air cleaner 12 is connected to the air introduction duct 11, an air intake passage 20 formed by an air pipe 14 is connected to the air cleaner 12, and the downstream end thereof is connected to an air cleaner 12. A throttle body 16 having a throttle valve 15 (see FIG. 2) installed therein is attached. The downstream side of this throttle body 16 is connected to an intake manifold 17, and a branch pipe 17a branches to each cylinder of the intake manifold 17.
is connected to the engine body 18 to supply intake air to each cylinder.

In the intake device 10 as described above, a resonator 2 is installed in the intake passage 20 of the air pipe 14 on the upstream side of the throttle valve 15 (throttle body 16).
1 is installed via a communication path 22. This resonator 2
1 has a predetermined volume, and is designed to resonate pressure waves acting from the intake port side of the engine downstream of the throttle valve 15 to obtain a supercharging effect at the synchronized rotation speed and increase torque.

The structure of the installation part of the resonator 21 is shown in FIGS. 2 and 3. An intake passage 20 formed through the inside of the throttle body 16 has a circular cross section, and a butterfly type throttle is installed in this intake passage 20. A valve 15 is rotatably arranged. The throttle valve 15 has a substantially disk shape, and its central portion is supported by a throttle shaft 15a.The throttle shaft 15a passes through the center of the intake passage 20 and is pivotally supported. Accordingly, the opening/closing operation is performed to a predetermined opening degree. As shown in solid lines in FIG.
0 is closed, and the throttle shaft 15a is closed as shown by the chain line.
The throttle shaft 15a rotates around the center to open the throttle shaft 15a.
The opening amount becomes larger in the portion away from 5a.

[0015] A connecting portion 1 is formed protrudingly in a pipe shape on the upstream side of the intake passage 20 of the throttle body 16.
The downstream connection end 14a of the air pipe 14 constituting the upstream intake passage 20 is fitted into the end 6a, and is tightened with a fastening band (not shown) or the like. A communication path 22 that communicates with the resonator 21 is branched near the downstream end of the air pipe 14, and a box-shaped resonator 21 is connected to the tip of the communication path 22. The communication path 22 is
The air pipe 14 is curved into a substantially U-shape from the opening 23 and extends in the direction opposite to the communication direction, and a resonator 21 is installed at the tip 22a of the air pipe 14.
A connecting portion 21b protruding from a box-shaped body 21a having a predetermined volume is fitted into the connecting portion 21b, and an introduction pipe 21c having a slightly curved inner end is disposed at the center of the connecting portion 21b. .

The opening 23 of the communication passage 22 with respect to the air pipe 14 is perpendicular to the throttle shaft 15a of the throttle valve 15 in a direction in which the opening amount increases, and moreover, the opening 23 of the communication passage 22 with respect to the air pipe 14 is arranged in a direction in which the opening amount becomes larger. 15 is a position that opens toward the upstream side, and is formed near the upstream side of the throttle valve 15. Note that the distance L in the intake flow direction between the center of the opening 23 and the throttle shaft 15a is set within the range of D/2≦L≦2D with respect to the bore diameter D of the intake passage 20 of the throttle body 16. In the illustrated case, it is set near 2D.

According to the above configuration, when the throttle valve 15 is in the fully closed state, the pressure wave downstream of the throttle valve 15 and the intake negative pressure do not act on the resonator 21, and the throttle valve 15 is opened to a low or medium opening degree, the intake air flowing to the engine side flows intensively through the part opened to the downstream side on the left side of FIG. On the right side where it opens to the side, the intake flow rate is low, and intake resistance and peeling noise due to the opening 23 are reduced. As the throttle valve 15 opens, the intake passage 20 downstream of the throttle valve 15 opens.
The pressure waves generated in
It resonates with characteristics depending on its volume and path shape.

In the above embodiment, the communication path 22 to the resonator 21 is curved into a substantially U-shape because of the relationship between the space in which the resonator 21 is installed and the position where the opening 23 is formed. This is done as a result of connecting the two, and the resonator 2 is placed on the extension of the opening 23.
1, the above curved shape is not required.

[Brief explanation of drawings]

FIG. 1 is a plan view showing the overall configuration of an engine intake system according to an embodiment of the present invention.

[Figure 2] Cross-sectional view of the main parts of the resonator installation part

[Figure 3] Cross-sectional view taken along line A-A in Figure 2

[Explanation of symbols]

10 Intake device 14 Air pipe 15 Throttle valve 15a Throttle shaft 16 Throttle body 20 Intake passage 21 Resonator 22 Communication path 23 Opening

Claims (2)

[Claims] 1. An intake system for an engine in which a resonator having a predetermined volume is connected in communication through an opening formed in an intake passage, wherein the opening of the intake passage communicating with the resonator is located on the upstream side of a throttle valve. An intake air intake for an engine, characterized in that the throttle valve is provided in the vicinity and in a direction perpendicular to the throttle shaft of the throttle valve, and at a position where the throttle valve opens upstream in response to rotation of the throttle valve. Device. 2. A distance L between the center of the opening of the resonator and the throttle shaft is set in a range of D/2≦L≦2D with respect to a bore diameter D of the throttle valve portion. An intake system for an engine according to claim 1.