JPH08128367A - Air intake device - Google Patents

Abstract

PURPOSE: To reduce generation of an intake air abnormal sound by preventing a turbulent flow of an intake air flow by a groove part of a negative pressure passage. CONSTITUTION: An intake air device is provided with a throttle body 1 and an intake flange 2 connected to its downstream side end surface. A groove part 5 of a negative pressure passage to be communicated with an intake air passage 3 is arranged on a mating face with the intake flange 2 of the throttle body 1. An inclining groove part 5 which faces the groove part 5 and inclines toward a downstream side wall surface of the intake air passage 3 from the inmost end part of its groove part 5, is arranged on a mating face with the throttle body 1 of the intake flange 2. An intake air flow in the vicinity of the opening end of the groove part 5 of the negative pressure passage is smoothed by the inclining groove part 8 arranged on the mating face of the intake flange 2.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an intake device for introducing air into a cylinder of an engine.

[0002]

2. Description of the Related Art An example of a conventional intake device is shown in cross section in FIG. For convenience of explanation, the same reference numerals will be given to the parts that are considered to have the same or equivalent configurations as those of the embodiments described later. The intake device includes a throttle body 1 and an intake flange 2 connected to the downstream end surface thereof. A throttle valve 4 for opening and closing the intake passage 3 is rotatably supported on the throttle body 1 via a shaft 4a. A groove portion 5 of a negative pressure passage communicating with the intake passage 3 is provided on a mating surface of the throttle body 1 with the intake flange 2. The throttle body 1 of the intake flange 2 is provided at the opening of the groove portion 5 on the mating surface side.
The mating surface 2a with is facing. A device having substantially the same structure as the above-described intake device is disclosed in, for example, Japanese Patent Laid-Open No. 2-22751.
No. 8 publication.

[0003]

According to the above-mentioned conventional intake device, a part of the intake air flow strikes the portion of the mating surface 2a of the intake flange 2 with the throttle body 1 at the open end of the groove 5 of the negative pressure passage (see FIG. (Refer to the arrow A in the middle), turbulent flow due to the intake air flow, that is, entrainment occurs near the opening end of the groove portion 5, which causes a problem of abnormal intake noise called beep sound. The turbulent flow is particularly noticeable when the throttle valve 4 is open.

The technical problem to be solved by the present invention is as follows.
An object of the present invention is to provide an intake device capable of reducing the occurrence of intake noise by preventing turbulence of the intake flow due to the groove portion of the negative pressure passage.

[0005]

The invention according to claim 1 for solving the above-mentioned problems is provided with a throttle body and an intake flange connected to an end face on the downstream side thereof, and a mating surface with the intake flange of the throttle body is provided. In an intake device provided with a groove portion of a negative pressure passage communicating with an intake passage, a mating surface of the intake flange with a throttle body faces the groove portion and a wall surface on a downstream side of the intake passage from a deep end of the groove portion. The intake device is characterized in that an inclined groove portion that is inclined toward is provided. According to the invention of claim 2, when a plurality of groove portions of the negative pressure passage are provided,
The intake device according to claim 1, wherein the inclined groove portion is provided so as to face the plurality of groove portions.

[0006]

According to the intake device of the invention of claim 1, the inclined groove portion provided on the mating surface of the intake flange allows
The intake flow becomes smooth near the open end of the groove of the negative pressure passage. According to the intake device of the invention of claim 2, the intake flow becomes smoother in the vicinity of the open ends of the plurality of groove portions of the negative pressure passage, as compared with the case where the inclined groove portions are individually provided so as to face each groove portion.

[0007]

EXAMPLES Examples 1 to 3 of the present invention will be described in order. [Embodiment 1] An intake system of Embodiment 1 is shown in a sectional view in FIG. The intake system includes a throttle body 1 and an intake flange 2 connected to a downstream end surface of the throttle body 1 by a bolt or the like (not shown). The throttle body 1 and the intake flange 2 form a series of intake passages 3. Further, the intake passage 3 is provided in the throttle body 1.
A throttle valve 4 that opens and closes is rotatably supported via a shaft 4a. Although not shown, a surge tank is connected to the upstream end surface of the throttle body 1,
An engine head is connected to the downstream end surface of the intake flange 2.

A groove portion 5 of a negative pressure passage communicating with the intake passage 3 is provided on the mating surface of the throttle body 1 with the intake flange 2. In addition, a substantially L-shaped communication hole 6 that communicates the groove 5 with the outside of the body is formed at the rear end of the groove 5. A hose connecting tube 7 is attached to the open end of the communication hole 6. The mating surface of the intake flange 2 with the throttle body 1 is provided with an inclined groove portion 8 facing the groove portion 5. The bottom surface 8a of the inclined groove portion 8 is inclined from the rear end portion of the groove portion 5 toward the wall surface on the downstream side of the intake passage 3.

A sectional view taken along the line P--P of FIG. 1 is shown in FIG. 2, and an explanatory view of the throttle body is shown in FIG. FIG. 3A is a diagram showing a mating surface with the intake flange, and FIG. 3B is a sectional view. As is clear from these figures, the intake flange 2 of the throttle body 1
Two groove portions 5 are provided side by side on the mating surface 1a. The one groove portion 5 functions as a negative pressure port of a negative pressure passage leading to the throttle opener and the pressure regulator, and the other groove portion 5 functions as an outlet of a throttle bypass passage (negative pressure passage). Further, the inclined groove portion 8 of the intake flange 2 is individually provided so as to face each groove portion 5.

According to the intake system, the inclined groove portion 8 provided on the mating surface of the intake flange 2 makes the intake flow near the open end of the groove portion 5 of the negative pressure passage smoother than that of the conventional one (see FIG. 1). (Refer to the arrow in the middle), which can prevent the occurrence of turbulent flow, thereby reducing the occurrence of intake noise.

[Second Embodiment] A second embodiment will be described with reference to FIGS. 4 and 5. 4 is a sectional view of the intake device corresponding to the sectional view taken along the line P-P of FIG. 1, FIG. 5 (a) is a view showing a mating surface with the intake flange of the throttle body, and FIG. 4 (b) is a view of the throttle body. FIG. The parts that are considered to have the same or equivalent configurations to those in the first embodiment are designated by the same reference numerals, and duplicate description will be omitted. In addition, the same concept will be applied to the third embodiment, which will be described later. As is clear from the figure, the intake device of this example is the same as that of the first embodiment.
It is a modification of the intake flange 2 in
The inclined groove portion 81 (denoted by reference numeral 81) is formed by cutting out a portion between the two inclined groove portions 8 in the first embodiment.
Are provided so as to face over the two groove portions 5. The two groove portions 5 in this example are provided closer to each other than in the first embodiment. According to the intake device of this example, the plurality of groove portions 5 of the negative pressure passage are provided as compared with the case where the inclined groove portions are individually provided so as to face each groove portion 5 (see Embodiment 1).
The intake flow near the open end of becomes smoother,
This is effective in reducing the generation of abnormal noise.

[Third Embodiment] A third embodiment will be described with reference to FIGS. 6 and 7. 6 is a sectional view of the intake device corresponding to the sectional view taken along the line P-P of FIG. 1, FIG. 7A is a view showing a mating surface with the intake flange of the throttle body, and FIG. 7B is a sectional view of the throttle body. FIG. As is apparent from the figure, the intake device of this example is a modification of the throttle body 1 of the second embodiment, and a groove portion (reference numeral 5) obtained by cutting off a portion between the two groove portions 5 of the second embodiment.
1) and the groove portion 51 corresponding to the inclined groove portion 81 in the second embodiment.

[0013]

According to the intake device of the first aspect of the present invention, the intake air flow becomes smooth in the vicinity of the open end of the groove portion of the negative pressure passage, so that the occurrence of turbulence can be prevented and the occurrence of intake noise is reduced. be able to. According to the intake device of the second aspect of the present invention, when a plurality of groove portions of the negative pressure passage are provided, the intake flow becomes smoother than in the case where the inclined groove portions are individually provided so as to face each groove portion. Is effective in reducing the occurrence of.

[Brief description of drawings]

FIG. 1 is a cross-sectional view showing a first embodiment.

FIG. 2 is a sectional view taken along the line PP of FIG.

FIG. 3 is an explanatory diagram of a throttle body.

FIG. 4 is a sectional view showing a second embodiment.

FIG. 5 is an explanatory diagram of a throttle body.

FIG. 6 is a cross-sectional view showing a third embodiment.

FIG. 7 is an explanatory diagram of a throttle body.

FIG. 8 is an explanatory diagram showing a conventional example.

[Explanation of symbols]

 1 Throttle body 2 Intake flange 3 Intake passage 5,51 Negative pressure passage groove 8, 81 Inclined groove

Claims (2)

[Claims] 1. An intake system comprising a throttle body and an intake flange connected to a downstream end surface of the throttle body, and a groove portion of a negative pressure passage communicating with the intake passage is provided on a mating surface with the intake flange of the throttle body. An intake groove is provided on a mating surface of the intake flange with the throttle body, the inclined groove facing the groove and inclined from a rear end of the groove toward a wall surface on a downstream side of the intake passage. apparatus. 2. The intake device according to claim 1, wherein, when a plurality of groove portions of the negative pressure passage are provided, the inclined groove portion is provided so as to face over the plurality of groove portions.