JP2010168995A - Valve device for internal combustion engine - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a valve device for an internal combustion engine for restraining the intrusion of a fixation-causing substance into a clearance between a valve body and a valve support means. <P>SOLUTION: A valve shaft 14 includes a high pressure gas supply hole 14a in its axis and a pair of high pressure gas introduction holes 14b communicating with the high pressure gas supply hole 14a is arranged between adjacent valve bodies (shanks 13b) at angular interval of 180°. Intake air introduced into the high pressure gas supply hole 14a of the valve shaft 14 is injected into a bore 9 of a valve body 3 after being introduced from the high pressure gas introduction hole 14b into a clearance between a bearing 11a of a valve holder 11 and the shank 13b of the valve body 13. Thus, oil droplet and the fixation-causing substance are blocked by injecting intake air and unlikely to intrude to the clearance between the bearing 11a and the shank 13b. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a valve device of an internal combustion engine, and relates to a technique for suppressing the intrusion of a sticking factor substance into a gap between a valve body and a valve support means.

  A throttle valve, a swirl control valve, a butterfly valve such as an exhaust shutter is often mounted in an intake passage and an exhaust passage of an internal combustion engine. The butterfly valve includes a disk-shaped valve body, a valve shaft integrated with the valve body by fastening or press-fitting, an actuator connected to the valve shaft, and the like. The butterfly valve is rotatably held by a bearing (usually a sliding bearing) formed in the valve body. When driven by an actuator, the butterfly valve rotates in the bore (valve bore) of the valve body and The exhaust passage area is continuously changed.

  Among the butterfly valves described above, the throttle valve and the swirl control valve have a deposit made of non-volatile components, carbon, etc. (hereinafter referred to as a sticking factor substance) in the fuel due to blowback caused by valve overlap. May stick / deposit. If deposits accumulate on the outer periphery of the valve body, a clearance is generated between the valve body and the valve bore even in the fully closed position, which may increase fuel consumption during idle operation and deteriorate engine control accuracy. It was. Therefore, the outer peripheral end face of the valve body and the inner peripheral face of the valve bore facing the valve body are covered with a coating film in which an oleophilic component and an oil repellent component are dispersed, so that oil droplets that become deposit starting materials adhere to the valve body. And techniques for suppressing stagnation have been proposed (see Patent Documents 1 and 2).

JP 2008-38630 A JP 2008-38631 A

  According to the techniques of Patent Documents 1 and 2, deposit accumulation between the valve body and the valve bore can be suppressed, but it is possible to prevent oil droplets and sticking factor substances from entering the gap between the butterfly valve and the bearing. could not. In particular, since the swirl control valve is installed near the intake valve, the sticking factor substance often sticks / deposits gradually between the butterfly valve and the bearing. When the swirl control valves of a plurality of cylinders are connected in series and these swirl control valves share the valve shaft, the intake pipe pressure differs between adjacent cylinders due to the intake pulsation. Oil droplets and sticking factor substances are more likely to enter. For this reason, when such an internal combustion engine is operated for a long period of time, a malfunction of the swirl control valve (such as sticking when the valve body is closed) occurs, and smooth swirl control control cannot be performed, resulting in a reduction in fuel consumption. There is a possibility that an increase or a decrease in output is caused.

  The present invention has been made in view of such a background, and an object of the present invention is to provide a valve device for an internal combustion engine in which the sticking factor substance is prevented from entering the gap between the valve body and the valve support means.

  In order to solve the above-mentioned problems, a first invention is a valve device having a valve body provided in an intake passage or an exhaust passage of an internal combustion engine, and valve support means for rotatably supporting the valve body. And a high-pressure gas introduction means for introducing a high-pressure gas into a gap between the valve support means and the valve body.

  According to a second aspect of the invention, in the valve device for an internal combustion engine according to the first aspect of the invention, the valve main body rotates with the valve shaft as a rotation axis, and the high-pressure gas introduction means follows the axis of the valve shaft. And a high-pressure gas supply hole that communicates the high-pressure gas supply hole with the outer periphery of the valve shaft.

  According to a third aspect of the present invention, in the valve device for an internal combustion engine according to the first aspect, the high-pressure gas introduction means has a high-pressure gas supply recess formed on an outer periphery of the valve shaft. Item 6. A valve device for an internal combustion engine according to Item 1.

  According to a fourth aspect of the present invention, in the valve device for an internal combustion engine according to the first aspect of the invention, the high-pressure gas introduction means has a high-pressure gas supply hole that opens to an inner peripheral surface of the valve support means. .

  A fifth aspect of the invention is the valve device for an internal combustion engine according to the first to fourth aspects of the invention, wherein the internal combustion engine has an exhaust gas recirculation passage for circulating the exhaust gas from the exhaust passage to the intake passage. And the high-pressure gas introducing means has a high-pressure gas intake portion upstream of the opening portion of the exhaust gas recirculation passage in the intake passage.

  Further, a sixth aspect of the present invention is the internal combustion engine valve device according to the first to fourth aspects of the present invention, wherein the intake passage has an intake pressure increase portion where the intake pressure increases due to intake pulsation, The high-pressure gas introducing means has a high-pressure gas intake part at the intake pressure increasing portion.

  According to a seventh invention, in the valve device for an internal combustion engine according to the first to sixth inventions, the valve support means supports adjacent valve bodies, and the high-pressure gas introduction means is between the adjacent valve bodies. A high-pressure gas is introduced into the gap.

  The eighth invention is the valve device for an internal combustion engine according to the first to seventh inventions, wherein the high-pressure gas introduction means supplies high-pressure gas from a high-pressure gas supply source other than the intake passage and the exhaust passage. It is characterized by receiving.

  According to the first aspect of the present invention, even when the internal combustion engine is operated for a long period of time, it is difficult for oil droplets and sticking factor substances to enter between the valve support means and the valve body due to the high-pressure gas. Is effectively suppressed. In addition, according to the second invention, by using a steel pipe or the like, there is no need to make a high-pressure gas supply hole in the axial center of the valve shaft, and it is possible to realize cost reduction and man-hour reduction required for manufacturing. . In addition, according to the third aspect of the invention, a reliable operation of the valve device can be realized by forming a groove serving as a high-pressure gas supply recess on the outer periphery of a solid valve shaft having excellent strength and rigidity. . Further, according to the fourth invention, it is not necessary to provide a high-pressure gas supply hole or a high-pressure gas supply recess in the valve shaft, so that a more reliable operation of the valve device can be realized. Further, according to the fifth invention, since the EGR gas containing carbon or unburned fuel is hardly mixed in the high-pressure gas, the malfunction of the valve device is more effectively suppressed. According to the sixth aspect of the invention, even in a naturally aspirated engine, relatively high pressure intake air (high pressure gas) can be supplied to the valve device. Moreover, according to 7th invention, the structure of a high pressure gas introduction means can be simplified. Further, according to the eighth aspect of the invention, high-pressure gas can be supplied to the valve device even in a naturally aspirated engine in which there is no intake pressure increase portion in the intake passage.

It is a perspective view of the swirl control unit which concerns on 1st Embodiment. It is a disassembled perspective view of the swirl control unit which concerns on 1st Embodiment. FIG. 3 is an enlarged vertical sectional view of a part III in FIG. 1. It is IV-IV sectional drawing in FIG. It is a schematic diagram which shows the high pressure gas introduction path | route which concerns on 1st Embodiment. It is a schematic diagram which shows the effect | action of 1st Embodiment. It is a longitudinal cross-sectional view which shows the principal part of the swirl control unit which concerns on 2nd Embodiment. It is VIII-VIII sectional drawing in FIG. It is a schematic diagram which shows the effect | action of 2nd Embodiment. It is a longitudinal cross-sectional view which shows the principal part of the swirl control unit which concerns on 3rd Embodiment. It is a schematic diagram which shows the effect | action of 3rd Embodiment. It is a schematic diagram which shows the high pressure gas introduction path | route which concerns on 4th Embodiment. It is a schematic diagram which shows the high pressure gas introduction path | route which concerns on 5th Embodiment.

  Hereinafter, some embodiments in which the present invention is applied to a swirl control unit will be described in detail with reference to the drawings.

[First Embodiment]
FIG. 1 is a perspective view of the swirl control unit according to the first embodiment, FIG. 2 is an exploded perspective view of the swirl control unit according to the first embodiment, and FIG. 3 is an enlarged vertical sectional view of a portion III in FIG. 4 is a sectional view taken along the line IV-IV in FIG. 3, and FIG. 5 is a schematic diagram showing a high-pressure gas introduction path according to the first embodiment.

<< Configuration of First Embodiment >>
The swirl control unit 1 is installed in the center of a crankcase (between V banks) of a V-type 6-cylinder diesel engine (not shown), and as shown in FIG. 1, a valve body 2 for introducing intake air into one bank. And three valve bodies 3 for introducing the intake air into the other bank are alternately arranged. As shown in FIG. 2, the swirl control unit 1 opens and closes the valve assembly 7 by being driven by an upper housing 5, a lower housing 6, a valve assembly 7 sandwiched between the upper housing 5 and the lower housing 6, and an actuator (not shown). The drive link 8 is a main component. Reference numeral 9 in FIG. 1 indicates the bores of the valve bodies 2 and 3.

  As shown in FIGS. 2 to 4, the valve assembly 7 includes eight valve holders 11 held by the upper housing 5 and the lower housing 6, and six valve bodies rotatably supported by bearings 11 a of these valve holders 11. 13. A valve shaft 14 that passes through the rotational axis of each valve body 13 is provided. The valve body 13 includes a disc-shaped valve plate 13a, a shank 13b that protrudes from both ends of the valve plate 13a and is slidably fitted into the bearing 11a of the valve holder 11, and a through hole 13c into which the valve shaft 14 is press-fitted. And a predetermined gap S is provided between the shanks 13b of the adjacent valve bodies. The valve shaft 14 has a high-pressure gas supply hole 14a at its axis and a high-pressure gas introduction hole 14b communicating with the high-pressure gas supply hole 14a. The high-pressure gas introduction holes 14 b are formed in pairs for each valve holder 11 with an angular interval of 180 °, and are opened at positions corresponding to the gaps S between the shanks 13 b on the outer periphery of the valve shaft 14.

  As shown in FIG. 5, an air cleaner and a turbocharger (not shown) are installed upstream of the intake pipe 20 of the engine E, and a throttle valve 21 and a swirl control unit 1 are connected downstream of the turbocharger. Yes. Further, the exhaust pipe 22 and the intake pipe 20 are communicated with each other via an exhaust gas recirculation (hereinafter referred to as EGR) passage 23, and the EGR valve 24 installed in the EGR passage 23 is opened, thereby EGR gas is introduced from the pipe 22 into the intake pipe 20. In the case of this embodiment, a high-pressure gas intake unit 25 is installed on the upstream side of the EGR passage 23 in the intake pipe 20, and the intake air taken in from the high-pressure gas intake unit 25 passes through the high-pressure gas supply pipe 26. It introduce | transduces into the high pressure gas supply hole 14a of the valve shaft 14 mentioned above.

<< Operation of First Embodiment >>
When the engine E starts operation, the intake air pressurized by the turbocharger flows into the combustion chamber (not shown) via the intake pipe 20 as shown in FIG. After being combusted with the fuel injected from (not shown), it is discharged to the exhaust pipe 22. Further, in a predetermined operation region, when the EGR valve 24 is opened, a predetermined amount of EGR gas is introduced from the exhaust pipe 22 to the intake pipe 20.

  Downstream of the throttle valve 21, relatively high-pressure intake air (high-pressure gas) is taken from the high-pressure gas intake portion 25, and this intake air is introduced into the high-pressure gas supply hole 14 a of the valve shaft 14 via the high-pressure gas supply pipe 26. Is done. At this time, since the high-pressure gas intake 25 is provided upstream of the EGR introduction passage 23 in the intake pipe 20, the intake air introduced into the high-pressure gas supply hole 14a contains EGR gas containing carbon and unburned fuel. Is hardly mixed.

  The intake air introduced into the high-pressure gas supply hole 14a of the valve shaft 14 flows into the space S between the shanks 13b from the high-pressure gas introduction hole 14b as shown in the schematic diagram of FIG. After being introduced into the gap with the shank 13b, it is ejected into the bore 9 of the valve body 3. As a result, the oil droplets and the sticking factor substance are prevented from entering the gap between the bearing 11a and the shank 13b by being obstructed by the ejected intake air. As a result, there is almost no risk of malfunction of the swirl control valve (eg, sticking when the valve body is closed), and smooth swirl control control is possible even when the internal combustion engine is operated for a long period of time.

[Second Embodiment]
FIG. 7 is a longitudinal sectional view showing a main part of the swirl control unit according to the second embodiment, and FIG. 8 is a sectional view taken along line VIII-VIII in FIG.
As shown in FIGS. 7 and 8, the overall configuration of the second embodiment is the same as that of the first embodiment described above, but instead of the high-pressure gas introduction hole, a high-pressure gas introduction groove is formed on the outer periphery of the valve shaft 14. 14d (high pressure gas supply recessed part) is formed. As shown in the schematic diagram of FIG. 9, the second embodiment is the same in that the intake air is introduced into the gap between the bearing 11a of the valve holder 11 and the shank 13b of the valve main body 13, but the valve shaft 14 In addition, since a solid material having excellent strength and rigidity can be employed, the swirl control unit 1 can be operated more reliably.

[Third Embodiment]
FIG. 10 is a longitudinal sectional view showing a main part of the swirl control unit according to the third embodiment.
The overall configuration of the third embodiment is the same as that of the first embodiment described above, but a pair of upper and lower high-pressure gas supply holes 11b and a high-pressure gas introduction hole 11c are formed on the valve holder 11 side. As shown in the schematic diagram of FIG. 11, the third embodiment is the same in that the intake air is introduced into the gap between the bearing 11 a of the valve holder 11 and the shank 13 b of the valve body 13. In addition, since a solid cylindrical shape can be adopted, there is an advantage that the operation of the swirl control unit 1 becomes more reliable.

[Fourth Embodiment]
FIG. 12 is a schematic diagram showing a high-pressure gas introduction path according to the fourth embodiment.
The overall configuration of the fourth embodiment is the same as that of the first embodiment described above, but the intake pipe 20 is greatly curved between the throttle valve 21 and the swirl control unit 1, and the high-pressure gas intake 25 is It is installed in the curved part 20a. Since the curved portion 20a is an intake pressure increasing portion where the pressure of the intake air increases due to the intake pulsation, for example, even in a naturally aspirated engine, a relatively high pressure intake air (high pressure) is provided by providing the high pressure gas intake portion 25 in the portion. Gas) can be supplied to the swirl control unit 1.

[Fifth Embodiment]
FIG. 13 is a schematic view showing a high-pressure gas introduction path according to the fifth embodiment.
The overall configuration of the fifth embodiment is the same as that of the first embodiment described above, but the high-pressure gas supply pipe 26 is connected to an engine-driven or electric air pump 27, and the compressed air discharged from the air pump 27 is Supplied to the swirl control unit 1. In the present embodiment, by adopting such a configuration, high-pressure gas can be supplied to the swirl control unit 1 even in a naturally aspirated engine in which a curved portion does not exist in the intake pipe 20.

  Although the description of the specific embodiment is finished as described above, the present invention is not limited to the above-described embodiments and can be widely modified. For example, in the above-described embodiment, the present invention is applied to a swirl control unit in which a plurality of valve bodies are provided in series, but the present invention is applied to other types of valve devices such as a throttle valve and an exhaust shutter having a single valve body. Is of course applicable. In the above embodiment, the shank of the valve body is supported by the bearing of the valve holder. However, the valve shaft may be supported by the bearing of the valve body or the valve holder. In addition, the specific shape and number of high-pressure gas supply holes, high-pressure gas supply recesses, and high-pressure gas introduction holes can be changed as appropriate without departing from the spirit of the present invention.

1 Swirl control unit (valve device)
11 Valve holder (valve support means)
11a Bearing 11b High-pressure gas supply hole 11c High-pressure gas introduction hole 13 Valve body 13b Shank 14 Valve shaft 14a High-pressure gas supply hole 14b High-pressure gas introduction hole 14d High-pressure gas introduction groove (high-pressure gas supply recess)
20 Intake pipe (intake passage)
20a Curved part (Intake pressure rise part)
23 EGR passage (exhaust gas recirculation passage)
25 High-pressure gas intake 26 High-pressure gas supply pipe 27 Air pump (high-pressure gas supply source)
E engine (internal combustion engine)
S gap

Claims (8)

A valve device having a valve body provided in an intake passage or an exhaust passage of an internal combustion engine, and valve support means for rotatably supporting the valve body,
A valve device for an internal combustion engine, comprising high-pressure gas introduction means for introducing high-pressure gas into a gap between the valve support means and the valve body. The valve body rotates with the valve shaft as a rotation axis,
The high-pressure gas introduction means has a high-pressure gas supply hole formed along the axis of the valve shaft, and a high-pressure gas introduction hole that communicates the high-pressure gas supply hole with the outer periphery of the valve shaft. The valve device for an internal combustion engine according to claim 1.   2. The valve device for an internal combustion engine according to claim 1, wherein the high-pressure gas introduction unit has a high-pressure gas supply recess formed on an outer periphery of the valve shaft.   2. The valve device for an internal combustion engine according to claim 1, wherein the high-pressure gas introduction unit has a high-pressure gas supply hole that opens to an inner peripheral surface of the valve support unit. The internal combustion engine includes an exhaust gas recirculation passage for circulating exhaust gas from the exhaust passage to the intake passage,
The said high-pressure gas introduction means has a high-pressure gas intake part upstream from the opening part of the said exhaust gas recirculation passage in the said intake passage, The Claim 1 characterized by the above-mentioned. Valve device for an internal combustion engine. In the intake passage, there is an intake pressure increase portion where the intake pressure increases due to intake pulsation,
The valve device for an internal combustion engine according to any one of claims 1 to 4, wherein the high-pressure gas introduction means has a high-pressure gas intake portion at the intake pressure increase portion. The valve support means supports an adjacent valve body;
The valve device for an internal combustion engine according to any one of claims 1 to 6, wherein the high-pressure gas introduction unit introduces a high-pressure gas into a gap between the adjacent valve bodies.   8. The internal combustion engine according to claim 1, wherein the high-pressure gas introduction unit receives supply of high-pressure gas from a high-pressure gas supply source other than the intake passage and the exhaust passage. Engine valve device.

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