Intake device of internal combustion engine

Abstract

An intake control valve of an intake device of an internal combustion engine comprises a given portion defined by an air intake passage that leads to a combustion chamber of the engine through an intake valve; a pivot shaft passing through the given portion; and a valve plate secured to the pivot shaft to pivot therewith within the given portion. The valve plate is pivotal between a close position to close the air intake passage and an open position to open the air intake passage. When the valve plate assumes the close position, the interior of the air intake passage downstream the valve plate is formed with mutually isolated first and second air flows that are separated and oriented to enhance a flow of air/fuel mixture in the combustion chamber.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

Other objects and advantages of the present invention will become apparent from the following description when taken in conjunction with the accompanying drawings, in which:

FIG. 1 is a diagrammatic system view of an internal combustion engine to which the present invention is practically applied;

FIG. 2A is a schematically illustrated intake device of a first embodiment of the present invention under a condition wherein an intake control valve is closed;

FIG. 2B is a schematic view taken from the direction of an arrow “Y” of FIG. 2A;

FIG. 2C is a sectional view taken along the line “Z-Z” of FIG. 2B, showing an arrangement of a pivot shaft to which a valve plate of the intake control valve is secured;

FIG. 2D is a view similar to FIG. 2C, but showing a modification of the arrangement of the pivot shaft;

FIG. 3 is a view similar to FIG. 1, but showing advantageous operation of the intake device of the first embodiment of the present invention;

FIGS. 4A to 4D are views similar to FIG. 2B, but showing first, second, third and fourth modifications of the intake device of the first embodiment of the present invention;

FIGS. 5A to 5E are views also similar to FIG. 2B, but showing fifth, sixth, seventh, eighth and ninth modifications of the intake device of the first embodiment of the present invention;

FIG. 6A is a view similar to FIG. 2A, but showing an intake device of a second embodiment of the present invention;

FIG. 6B is a view similar to FIG. 6A, but showing advantageous operation of the intake device of the second embodiment of the present invention; and

FIG. 7 is a view similar to FIG. 6A, but showing a modification of the intake device of the second embodiment.

Claims

1. An intake device of an internal combustion engine, comprising: an air intake passage leading to a combustion chamber of the engine through an intake valve;a fuel injection valve provided in the air intake passage to inject a fuel into the air intake passage; andan intake control valve arranged in the air intake passage at a position upstream of the fuel injection valve,wherein the intake control valve comprises:a given portion defined by the air intake passage;a pivot shaft passing through the given portion;a valve plate secured to the pivot shaft to pivot therewith within the given portion, the valve plate being pivotal between a close position to close the air intake passage and an open position to open the air intake passage; andan arrangement that provides, when the valve plate assumes the close position, the interior of the air intake passage downstream the valve plate with mutually isolated first and second air flows that are separated and oriented to enhance a flow of air/fuel mixture in the combustion chamber.

2. An intake device as claimed in claim 1, in which the arrangement comprises: an upper side open portion that is provided when the valve plate assumes the close position, the upper side open portion being a given cut formed in an upper right half portion of the valve plate; anda lower side open portion that is provided when the valve plate assumes the close position, the lower side open portion being an open portion provided at an opposite position of the given cut with respect to an axial center line of the air intake passage,wherein a flow passage sectional area of the lower side open portion is smaller than that of the upper side open portion.

3. An intake device as claimed in claim 2, in which the lower side open portion is a clearance defined between the pivot shaft and a bottom wall of the given portion of the air intake passage.

4. An intake device as claimed in claim 3, in which the clearance extends between a left end of the valve plate to a middle portion of the same.

5. An intake device as claimed in claim 2, in which the lower side open portion is a recess formed on a left wall of the given portion of the air intake passage.

6. An intake device as claimed in claim 5, in which the recess extends between a lower end of the valve plate to a vertically middle portion of the same.

7. An intake device as claimed in claim 2, in which the lower side open portion is a cut formed in a lower left portion of the valve plate.

8. An intake device as claimed in claim 2, in which the lower side open portion is an opening formed in a lower left portion of the valve plate.

9. An intake device as claimed in claim 2, in which the valve plate is secured at its lower end to the pivot shaft, and thus the intake control valve serves as a flap type valve.

10. An intake device as claimed in claim 2, in which the valve plate is secured at its middle portion to the pivot shaft, and thus the intake control valve serves as a butterfly type valve.

11. An intake device as claimed in claim 2, further comprising a partition wall that is provided in the air intake passage downstream the intake control valve to reinforce the separation between the first and second air flows.

12. An intake device as claimed in claim 11, in which the partition wall has opposed side ends respectively fixed to diametrically opposed portions of the air intake passage.

13. An intake device as claimed in claim 12, in which the partition wall has an axially extending middle portion that extends on and along the axial center line of the air intake passage.

14. An intake device as claimed in claim 13, in which the valve plate of the intake control valve is sized to close only the passage for the second air flow.

15. An intake device as claimed in claim 2, in which a lower part of the given portion of the air intake passage is formed with a recess into which the valve plate is neatly received when the valve plate assumes the open position.

16. An intake device as claimed in claim 2, in which the air flow passage sectional area of the lower side open portion is about 20 to 25% of that of the upper side open portion.

17. An intake device as claimed in claim 3, in which the bottom wall of the given portion of the intake passage is formed with a rounded groove that extends along the pivot shaft keeping a given clearance therebetween.

18. An intake device as claimed in claim 2, in which the given portion of the air intake passage has a rectangular cross section, and in which the valve plate is rectangular in shape.

19. An intake device of an internal combustion engine, comprising: an air intake passage leading to a combustion chamber of the engine through an intake valve;a fuel injection valve provided in the air intake passage to inject a fuel into the air intake passage;a throttle valve installed in the air intake passage upstream of the fuel injection valve to control the amount of air led to the combustion chamber;a control unit that controls operation of the fuel injection valve and the throttle valve in accordance with an operation condition of the engine; andan intake control valve arranged in the air intake passage between the throttle valve and the fuel injection valve,wherein the intake control valve comprises:a rectangular parallelepiped given portion defined by the air intake passage;a pivot shaft passing through the given portion, the pivot shaft being controlled by the control unit;a rectangular valve plate secured to the pivot shaft to pivot therewith within the given portion, the rectangular valve plate being pivotal between a close position to close the air intake passage and an open position to open the air intake passage; andan upper side open portion that is provided when the valve plate assumes the close position, the upper side open portion being a given cut formed in an upper right half portion of the valve plate; anda lower side open portion that is provided when the valve plate assumes the close position, the lower side open portion being an open portion provided at an opposite position of the given cut with respect to an axial center line of the air intake passage,wherein a flow passage sectional area of the lower side open portion is smaller than that of the upper side open portion.