JPH11294199A - Intake air flow control valve - Google Patents

Abstract

PROBLEM TO BE SOLVED: To eliminate the generation of an edge tone which is transmitted to the upstream of a throttle valve element and amplified like self-excited vibration by making an air stream flowing through a raised edge part of the throttle valve element into a discontinuous stream. SOLUTION: This valve includes a throttle valve shaft 4 which intersects perpendicularly to the axial direction of an air passage 1 and is rotatable, and a butterfly-like throttle valve element 5 journalled to the throttle valve shaft 4. The throttle valve element 5 is turned or returned in such a direction that the outer peripheral part of the throttle valve element and a part of the spherical surface of a raised form 6 or a curved surface 6a in its vicinity separate from the wall part 2, thereby opening and closing an air passage. An edge part 6b shaped like a raised form 6 is provided with plural groove parts 8 shaped to be wavy. The groove parts 8 disturb an air stream 7 flowing in two dimensions and continuously in the axial direction on the edge part 6b to be made three-dimensional, thereby producing a discontinuous air steam. Thus, the generation of edge tone can be eliminated.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a flow control valve for an internal combustion engine using a butterfly valve (butterfly valve), and more particularly to a flow control valve suitable for a throttle valve (throttle valve) of an internal combustion engine for an automobile.

[0002]

2. Description of the Related Art Conventionally, butterfly valves have been mainly used as throttle valves for automobiles. As a conventional example using a butterfly valve, an apparatus disclosed in Japanese Patent Publication No. 61-54936 is known. In the valve body rotatably supported as shown in FIG. 6, a part of a spherical surface or a curved shape close to the spherical surface for maintaining a small gap with the bore inner wall of the throttle body in a low opening range is provided on the bore inner wall. ing.

Further, in the device described in Japanese Patent Publication No. 3-74530, a gap between an inner wall of a throttle body and a bore of a throttle body is kept small in a low opening region by a valve body rotatably supported as shown in FIG. A protruding shape of a part of the spherical surface or a curved surface close to the spherical surface is provided on the valve body.

In these publications, as shown by a broken line 9 in FIG. 6, the rate of change of the opening area with respect to the valve opening in the low opening range is reduced, and particularly, the rate of change of the opening area in the low opening range is large. It discloses that a device capable of improving drivability (drivability) in a throttle body having a diameter can be provided.

[0005]

In the prior art shown in FIG. 4, the throttle valve 5 in the air passage has a wing shape. The air flow 7 continuously flows through the edge portion 6a of the corresponding raised shape 6, and becomes a sound wave generated by the continuous vortex emission, which propagates to the upstream side of the throttle valve body and is amplified by self-excited vibration to be amplified by the edge tone. Generates a loud sound called.

An object of the present invention is to eliminate the generation of the edge tone.

[0007]

The structure is such that the air flow 7 flowing through the edge 6a of the raised shape 6 of the throttle valve 5 has a discontinuous flow.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An intake air control valve according to the present invention will be described below with reference to the embodiments shown in FIGS.

FIG. 2 shows an embodiment of the present invention. 1 is a cylindrical air passage for passing air from an upstream side to a downstream side, 2 is a wall of the air passage 1, and 3 is a wall 2. , A throttle valve shaft that is rotatable at right angles to the axial direction of the air passage 1, 5 is a butterfly-shaped throttle valve that is axially supported by the throttle valve 4, and 6 is a throttle valve 5. The throttle element 5 has a curved shape close to or part of the spherical surface of the throttle body outer periphery and the raised shape 6 due to the rotation of the throttle valve 4. The opening and closing of the air flow path is performed by turning or returning the 6a away from the wall 2.

In FIG. 3, which is an enlarged view of FIG. 2, an air flow 7 flows from the upstream side to the downstream side between the wall portion 2 and the edge portion 6b in the raised shape 6.

Therefore, the configuration so far is the same as that of the conventional example shown in FIG. 5, and is intended to improve drivability.

In the embodiment shown in FIG. 1, a plurality of groove portions 8 having a wave shape as shown in FIG.

The groove 8 disturbs the two-dimensionally and continuously flowing air flow 7 in the axial direction on the edge portion 6b, thereby making the air flow 7 three-dimensional and a discontinuous air flow.

The sound wave emitted from the two-dimensional and continuous vortex propagates to the upstream side of the throttle body, is amplified by self-excited vibration, and generates noise called edge tone. According to the operation of the present invention, eddy emission is made three-dimensional, so that generation of edge tones can be eliminated.

[0015]

According to the present invention, the rate of change of the opening area with respect to the valve opening in the low opening range is reduced, and particularly in a large-diameter throttle body having a large opening area change rate in the low opening range. Ensuring drivability is improved,
It is possible to meet the needs of throttle bodies of various diameters, to reduce noise due to edge tones, and to provide inexpensively.

[Brief description of the drawings]

FIG. 1 is a perspective view showing one embodiment of a throttle valve according to the present invention.

FIG. 2 is a sectional view showing an embodiment of a throttle valve according to the present invention.

FIG. 3 is an enlarged sectional view showing one embodiment of a throttle valve according to the present invention.

FIG. 4 is a perspective view showing a conventional example of a throttle body.

FIG. 5 is a cross-sectional view showing a conventional example of a throttle body.

FIG. 6 is a characteristic diagram showing a relationship between an opening degree of a throttle body and a vent opening area.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Air passage, 2 ... Wall part, 3 ... Main body, 4 ... Throttle valve shaft, 5 ...
Throttle valve element, 6: raised shape, 6a: curved surface, 6b: edge portion,
7 ... air flow, 8 ... groove.

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Akihiko Miyata 2520 Ojitakaba, Hitachinaka City, Ibaraki Prefecture Inside the Automotive Equipment Division, Hitachi, Ltd. (72) Inventor (72) Inventor: Meiji Iida, Meiji Laboratory, Katsumachi, Tsuchiura-shi, Ibaraki Pref.

Claims (4)

[Claims] 1. A main body forming an air passage for supplying air to an internal combustion engine, a valve body rotatably supported in the air passage at right angles to an axial direction of the air passage, and the valve body. A valve body having at least one raised shape near the outer peripheral edge of the valve body, wherein at least one groove is formed in the axial direction of the air passage on the upper surface of the edge of the raised shape. 2. The flow control valve according to claim 1, wherein at least one projection is provided on an upper surface of the raised edge in the axial direction of the air passage. 3. The flow control valve according to claim 1, wherein at least one groove is formed on an upper surface of the raised edge in a direction perpendicular to the air passage. 4. The flow control valve according to claim 1, wherein at least one projection is provided on an upper surface of the raised edge in a direction orthogonal to the air passage.