JP2000038933A - Throttle valve device of internal combustion engine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To increase the degree of freedom of the design for forming an opening in a simple structure, as well as to reduce the air flow speed near the opening to reduce the generation of a suction sound. SOLUTION: A projection 5 is provided near the part separated the most in the peripheral direction from a valve shaft 12, in the inner wall of a throttle body 1 between an opening 17 and a throttle valve 11. As a result, even though the opening 17 is formed near the part most distant in the peripheral direction from the valve shaft 11, the air flow speed near the opening 17 is reduced securely, so as to prevent pressure flactuation from generating resonance in an auxiliary air passage 7. Consequently, the generation of intake sound can be reduced. Furthermore, by a relatively simple structure of providing a projection 5, the air flow speed near the opening 17 can be reduced to reduce the generation of the intake sound, resulting in enhancing the designing freedom degree to form the opening 17 as well as reducing the manufacturing cost.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an internal combustion engine (hereinafter referred to as "internal combustion engine").
"The internal combustion engine" is referred to as an engine).

[0002]

2. Description of the Related Art Conventionally, a throttle body is provided in an intake passage of an engine, and the amount of intake of the engine is controlled by a throttle valve. A bypass passage is formed in the throttle body so as to bypass the upstream and downstream sides of the throttle valve installation portion. The bypass passage constitutes a gas passage for air and blow-by gas, bypassing the throttle valve.
The outlet side passage leading to the throttle valve downstream of the bypass passage is formed so as to open substantially perpendicularly to a throttle main passage as an intake passage.

[0003]

For this reason, conventionally, when the throttle valve is opened by depressing the accelerator, the air flowing through the throttle main passage is separated at each part of the bypass outlet side passage opening, and the pressure fluctuation is caused by the bypass. There is a problem in that resonance occurs in the passage, causing the generation of intake noise.

In the throttle valve device disclosed in Japanese Patent Application Laid-Open No. 59-49342, the bypass outlet side passage and the throttle main passage are connected to each other with a curved surface or a tapered shape, thereby forming the bypass outlet side passage opening. In this case, the air separation phenomenon is reduced, the pressure fluctuation is reduced, and the generation of intake noise is reduced.

However, in the throttle valve device disclosed in Japanese Patent Application Laid-Open No. 59-49342, the vicinity of the portion of the inner wall of the throttle body that is farthest from the valve shaft of the throttle valve in the circumferential direction, that is, the center of the bypass outlet side passage opening. When the above-mentioned opening is formed at a position where the imaginary line connecting the portion and the center of the throttle valve is substantially orthogonal to the valve axis, when the throttle is opened by stepping on the accelerator, the most circumferentially extending from the valve shaft on the inner wall of the throttle body. Since the air flow velocity after passing through the throttle valve in the vicinity of the distant portion is relatively high, it is difficult to reduce the air separation phenomenon at each portion of the opening, and it is difficult to reduce the generation of intake noise. there were.

The present invention has been made to solve such a problem, and provides an engine throttle valve device capable of reducing the air flow velocity near the opening and reducing the generation of intake noise. The purpose is to do. Another object of the present invention is to provide an engine throttle valve device capable of increasing the degree of freedom in designing an opening by a simple configuration.

[0007]

According to the throttle valve device for an engine according to the first aspect of the present invention, the gas passage opening downstream of the throttle valve on the intake side is formed in the throttle body, and the air flow near the opening is disturbed. Since the turbulent flow generating means for generating the flow is provided on the upstream side of the intake of the gas passage, when the accelerator is depressed and the throttle valve is opened, a turbulent flow is generated in the intake air near the opening. For this reason, the air flow velocity near the opening can be reduced, and the pressure fluctuation can be prevented from resonating in the gas passage. Therefore, generation of intake noise can be reduced.

According to the throttle valve device for an engine according to the second aspect of the present invention, the turbulent flow generating means is provided on the inner wall of the throttle body between the opening and the throttle valve, so that the air flow velocity near the opening is ensured. And the occurrence of intake noise can be reliably reduced.

According to the throttle valve device for an engine according to the third aspect of the present invention, a virtual connection between the turbulence generating means and the center of the throttle valve is provided near the portion of the inner wall of the throttle body which is farthest from the valve shaft in the circumferential direction. Turbulence generating means is provided at a position where the line is substantially perpendicular to the valve shaft. For this reason, even if the opening is formed in the vicinity of the portion of the inner wall of the throttle body that is farthest from the valve shaft in the circumferential direction, the air flow velocity near the opening can be reduced, and the generation of intake noise can be reduced. Therefore, the degree of freedom in designing the opening can be increased.

According to the throttle valve device for an engine according to the fourth aspect of the present invention, since the turbulent flow generating means is provided near the outer periphery of the valve body, the air flow velocity near the opening is reliably reduced, and the generation of intake noise is generated. Can be reliably reduced.

According to the throttle valve device for an engine according to the fifth aspect of the present invention, the turbulent flow generating means is provided near the outer periphery farthest from the valve shaft in the circumferential direction. Even if the opening is formed in the vicinity of the farthest part, the air flow velocity in the vicinity of the opening can be reduced, and the generation of intake noise can be reduced. Therefore, the degree of freedom in designing the opening can be increased.

According to the throttle valve device for an engine according to the sixth aspect of the present invention, since the turbulent flow generating means has an uneven shape, a turbulent flow is generated in the intake air near the opening with a simple configuration to reduce the air flow velocity. Thus, the generation of the intake noise can be reduced. Therefore, the manufacturing cost can be reduced, and the degree of freedom in designing the opening can be increased.

[0013]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a block diagram showing a first embodiment of the present invention; (First Embodiment) FIGS. 1 and 2 show an engine throttle valve device according to a first embodiment of the present invention. As shown in FIG.
A throttle main passage 10 as a cylindrical intake passage is formed by the inner wall 1a of the throttle body 1, and a rotatable throttle valve 11 for adjusting the opening area of the throttle main passage 10 is provided in the middle of the throttle main passage 10. The throttle valve 11 is
Valve shaft 12 rotatably supported by throttle body 1
And a valve body 13 that rotates together with the valve shaft 12 to adjust the amount of intake air flowing through the throttle main passage 10. The valve shaft 12 is rotated via a drive lever (not shown) by depressing an accelerator pedal (not shown). In the state shown in FIG. 2, the throttle valve 11 is in a fully closed state.

When the throttle body 1 is mounted on a vehicle, the downstream side of the intake is airtightly connected to a surge tank (not shown), and the upstream side of the airtight is airtightly connected to an intake duct (not shown). An end face 3 on the downstream side of the intake of the throttle body 1 has a pressure introduction path 6 for pressure detection as a pressure detection introduction path and an idle speed control valve (described later) of the auxiliary air control device 8 bypassing the throttle valve 11. Less than,
The “idle speed control valve” is referred to as an ISCV.) By opening the valve 18, the auxiliary air passage 7 as a gas passage that can communicate with the intake upstream side of the throttle main passage 10.
Opening 17 is formed.

As shown in FIG. 1, the ISCV 18 is provided in the auxiliary air passage 7 that bypasses the throttle valve 11. The inlet side of the auxiliary air passage 7 opens substantially perpendicularly to the inner wall 1a of the throttle body 1 forming the throttle main passage 10 on the upstream side of the intake air of the throttle valve 11. The outlet side of the auxiliary air passage 7 is connected to the throttle body 1 which forms the throttle main passage 10 on the downstream side of the intake air of the throttle valve 11.
The opening 17 is formed substantially perpendicularly to the inner wall 1a of the opening.

As shown in FIG. 2, the opening 17 is formed at a position where an imaginary line connecting the center of the opening 17 and the center of the throttle valve 11 is substantially orthogonal to the valve shaft 12. That is,
An opening 17 is formed in the inner wall 1a of the throttle body 1 in the vicinity of the portion farthest from the valve shaft 12 in the circumferential direction.

As shown in FIG. 1 and FIG.
A projection 5 as a turbulence generating means is provided on an inner wall 1a of the throttle body 1 between the throttle valve 11 and the throttle valve 11. The circumferential distance from one end 5 a to the other end 5 b of the projection 5 is formed larger than the circumferential distance of the opening 17. The angle θ formed by an imaginary line connecting one end 5a of the projection 5 and the center of the throttle valve 11 with the valve shaft 12 is approximately 40 °.
Angle. Therefore, the projection 5 is provided at a position where an imaginary line connecting the projection 5 and the center of the throttle valve 11 is substantially orthogonal to the valve shaft 12. That is, the protrusion 5 is provided in the vicinity of a portion of the inner wall 1a of the throttle body 1 that is farthest from the valve shaft 12 in the circumferential direction. The radial distance, ie, height, of the projection 5 is approximately 0.3 mm, and the distance, ie, the width, of the projection 5 in the direction of intake air flow is approximately 0.1 mm. However, the above numerical values differ depending on the type of engine, displacement, and the like. The projections 5 are formed by cutting the inner wall 1a of the throttle body 1, or by using a molybdenum disulfide coating film or the like. In FIG. 1, the rotation direction of the throttle valve 11 may be either clockwise or counterclockwise.

Next, a comparative example in which the projection 5 of the first embodiment shown in FIG. 1 is not provided will be described with reference to FIG. First
The same reference numerals are given to the same components as those in the embodiment. In the comparative example, as shown in FIG. 6, no protrusion is provided on the inner wall 1a of the throttle body 1 between the opening 17 and the throttle valve 11. For this reason, when the accelerator is depressed and the throttle valve 11 is opened, the air flow velocity after passing through the throttle valve 11 near the portion of the inner wall 1a of the throttle body 1 that is farthest from the valve shaft 12 in the circumferential direction becomes relatively high. Therefore, the opening 1
There is a problem that a separation phenomenon occurs in each part of the air passage 7, and the pressure fluctuation resonates in the auxiliary air passage 7, causing the generation of an intake noise.

On the other hand, in the first embodiment, the opening 17
Since the protrusion 5 is provided on the inner wall 1a of the throttle body 1 between the throttle valve 11 and the throttle valve 11, when the throttle valve 11 is opened by depressing the accelerator, a turbulent flow is generated in the intake air near the protrusion 5. For this reason, a turbulent flow is generated in the intake air in the vicinity of the opening 17 to reduce the air flow velocity, and it is possible to prevent the pressure fluctuation from resonating in the auxiliary air passage 7. Therefore, generation of intake noise can be reduced.

Further, in the first embodiment, the imaginary line connecting the projection 5 and the center of the throttle valve 11 is substantially perpendicular to the valve shaft 12, ie, from the valve shaft 12 on the inner wall 1a of the throttle body 1 in the circumferential direction. The projection 5 is provided in the vicinity of the part farthest from the valve shaft 11, so that the opening 17 is formed in the vicinity of the part farthest from the valve shaft 11 on the inner wall 1 a of the throttle body 1 in the circumferential direction. The air flow velocity in the vicinity of the section 17 can be reliably reduced, and the generation of intake noise can be reliably reduced. Therefore, the degree of freedom in designing the opening 17 can be increased.

Furthermore, in the first embodiment, the air flow velocity near the opening 17 can be reduced with a relatively simple structure in which the projections 5 are provided, and the generation of intake noise can be reduced. Therefore, the manufacturing cost can be reduced.

(Second Embodiment) A second embodiment in which a recess is formed instead of the projection 5 of the first embodiment shown in FIG. 1 will be described with reference to FIG. The same components as those in the first embodiment are denoted by the same reference numerals.

As shown in FIG. 3, the opening 17 and the throttle valve 1
A recess 15 as a turbulent flow generating means is formed in the inner wall 1a of the throttle body between the first and second throttle bodies. The recess 15 is provided in the vicinity of a portion of the throttle body inner wall 1a that is farthest from the valve shaft 12 in the circumferential direction. The recess 15 is formed by cutting the inner wall 1a of the throttle body. Note that, in FIG. 3, an arrow 20 indicates a rotation direction of the throttle valve 11.

In the second embodiment, the depression 15 is formed in the inner wall 1a of the throttle body between the opening 17 and the throttle valve 11. Therefore, when the accelerator is depressed and the throttle valve 11 is opened, the vicinity of the depression 15 is formed. A turbulence is generated in the intake air. Therefore, a turbulent flow is generated in the intake air near the opening 17 to reduce the air flow velocity near the opening 17, and it is possible to prevent the pressure fluctuation from resonating in the auxiliary air passage 7. Therefore, generation of intake noise can be reduced.

Further, in the second embodiment, since the recess 15 is formed in the vicinity of the portion of the throttle body inner wall 1a that is farthest from the valve shaft 12 in the circumferential direction, the recess 15 is formed in the circumferential direction from the valve shaft 11 of the throttle body inner wall 1a. Although the opening 17 is formed in the vicinity of the farthest part, the air flow velocity in the vicinity of the opening 17 can be surely reduced, and the generation of intake noise can be surely reduced. Therefore, the degree of freedom in designing the opening 17 can be increased.

Furthermore, in the second embodiment, the air flow velocity near the opening 17 can be reduced with a relatively simple configuration in which the recess 15 is formed, and the generation of intake noise can be reduced. Therefore, the manufacturing cost can be reduced.

In the first or second embodiment described above, one projection or one recess is formed on the inner wall 1a of the throttle body between the opening 17 and the throttle valve 11, but in the present invention, the opening is A plurality of projections, a plurality of depressions, both of the projections and the depressions, a repetition of the projections and the depressions, or a rough surface may be formed on the inner wall of the throttle body between the portion and the throttle valve.

(Third Embodiment) A third embodiment in which a projection is provided on the valve body 13 instead of the recess 15 of the second embodiment shown in FIG. 2 will be described with reference to FIG. The same components as those of the second embodiment are denoted by the same reference numerals.

As shown in FIG. 4, the throttle valve 21 has a valve shaft 22.
And a valve body 23. A projection 25 as a turbulent flow generating means is provided on the surface of the valve body 23 on the upstream side of the intake and near the outer periphery on the opening 17 side farthest in the circumferential direction from the valve shaft 22 of the valve body 23. . The protrusion 25 is formed by cutting the valve body 23 or by using a molybdenum disulfide coating film or the like. In FIG. 4, an arrow 30 indicates a rotation direction of the throttle valve 21.

In the third embodiment, the valve shaft 2 of the valve body 23
Since the projection 25 is provided in the vicinity of the outer periphery farthest from the second in the circumferential direction, when the accelerator is depressed and the throttle valve 21 is opened, a turbulent flow is generated in the intake air near the projection 25. Therefore, although the opening 17 is formed in the vicinity of the portion of the throttle body inner wall 1a that is farthest from the valve shaft 21 in the circumferential direction, turbulence is generated in the intake air near the opening 17 and the opening 17 is formed. The air flow velocity in the vicinity can be reliably reduced, and the generation of intake noise can be reliably reduced. Therefore, the degree of freedom in designing the opening 17 can be increased.

Further, in the third embodiment, the projection 25
The air flow velocity near the opening 17 can be reduced with a relatively simple structure of providing the intake air, and the generation of intake noise can be reduced. Therefore, the manufacturing cost can be reduced.

(Fourth Embodiment) FIG. 5 shows a fourth embodiment in which a recess is formed instead of the projection 25 of the third embodiment shown in FIG.
This will be described with reference to FIG. The same components as those in the third embodiment are denoted by the same reference numerals.

As shown in FIG. 5, the throttle valve 31 is provided with a valve shaft 32.
And the valve body 33. A recess 35 as a turbulent flow generating means is provided on the surface of the valve body 33 on the upstream side of the intake air, near the outer periphery on the opening 17 side farthest in the circumferential direction from the valve shaft 32 of the valve body 33. . The recess 35 is formed by cutting the valve body 33 or the like. Note that, in FIG. 5, an arrow 40 indicates a rotation direction of the throttle valve 31.

In the fourth embodiment, the valve shaft 3 of the valve body 33
Since the depression 35 is formed in the vicinity of the outer periphery farthest from the second in the circumferential direction, when the accelerator is depressed and the throttle valve 31 is opened, a turbulent flow is generated in the intake air near the depression 35. For this reason, despite the fact that the opening 17 is formed near the portion of the throttle body inner wall 1a in the circumferential direction that is farthest from the valve shaft 31, turbulence is generated in the intake air near the opening 17 and the opening 17 is formed. The air flow velocity in the vicinity can be reliably reduced, and the generation of intake noise can be reliably reduced. Therefore, the degree of freedom in designing the opening 17 can be increased.

Further, in the fourth embodiment, the recess 35
The air flow near the opening 17 can be reduced with a relatively simple configuration of forming the air flow, and the generation of intake noise can be reduced. Therefore, the manufacturing cost can be reduced.

In the third or fourth embodiment described above, one projection or one recess is formed near the outer periphery of the valve body. However, in the present invention, a plurality of projections, A plurality of depressions, both projections and depressions, repetition of projections and depressions, or a rough surface may be formed.

In the embodiments described above, the present invention is applied to the throttle valve device of the engine provided with the auxiliary air passage 7 for the ISCV. However, in the present invention, the PCV passage for recirculating blow-by gas, The present invention can be applied to an engine throttle valve device having an EGR passage or another gas passage.

[Brief description of the drawings]

FIG. 1 is a sectional view of a throttle valve device for an engine according to a first embodiment of the present invention, taken along line II of FIG. 2;

FIG. 2 is a front view showing the throttle valve device for the engine according to the first embodiment of the present invention.

FIG. 3 is a sectional view showing an engine throttle valve device according to a second embodiment of the present invention.

FIG. 4 is a sectional view showing a throttle valve device for an engine according to a third embodiment of the present invention.

FIG. 5 is a sectional view showing an engine throttle valve device according to a fourth embodiment of the present invention.

FIG. 6 is a cross-sectional view illustrating a throttle valve device of an engine according to a comparative example.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Throttle body 1a Inner wall 5 Projection (turbulence generating means) 7 Auxiliary air passage (gas passage) 8 Auxiliary air control device 10 Throttle main passage (intake passage) 11 Throttle valve 12 Valve shaft 13 Valve body 15 Depression (turbulent flow generating means) 17) Opening 18 ISCV 21 Throttle valve 22 Valve shaft 23 Valve 25 Projection (turbulence generating means) 31 Throttle valve 32 Valve shaft 33 Valve 35 Depression (turbulence generating means)

Claims (6)

[Claims] 1. A throttle body forming an intake passage of an internal combustion engine, a valve shaft rotatably supported by the throttle body, and an amount of intake air that rotates together with the valve shaft and flows through the intake passage. A throttle valve having a valve element; a gas passage formed in the throttle body, which opens to a downstream side of the intake of the throttle valve; and a suction passage provided upstream of the opening of the gas passage upstream of the opening; A throttle valve device for an internal combustion engine, comprising: turbulence generating means for generating turbulence in the internal combustion engine. 2. The throttle valve device for an internal combustion engine according to claim 1, wherein the turbulent flow generating means is provided on an inner wall of the throttle body between the opening and the throttle valve. 3. The throttle valve device for an internal combustion engine according to claim 2, wherein said turbulent flow generating means is provided near a portion of said inner wall which is circumferentially farthest from said valve shaft. 4. The throttle valve device for an internal combustion engine according to claim 1, wherein said turbulent flow generating means is provided near an outer periphery of said valve body. 5. The throttle valve device for an internal combustion engine according to claim 1, wherein said turbulent flow generating means is provided in the vicinity of an outer periphery of said valve element which is farthest from said valve shaft in a circumferential direction. 6. The throttle valve device for an internal combustion engine according to claim 1, wherein said turbulent flow generating means has an uneven shape.