JP2001164929A - Engine exhaust valve device - Google Patents

Abstract

(57) Abstract: A valve shaft is rotatably supported via a bottomed cylindrical first sliding bearing and a cylindrical second sliding bearing on a valve body provided in the middle of an exhaust system of an engine. In an exhaust gas valve device for an engine in which an actuator is connected to the other end of a valve shaft protruding from the second slide bearing, almost all of the exhaust gas leakage over a long period of time is ensured while ensuring the operation reliability of the valve shaft with a simple structure. 0 ". An exhaust gas reservoir 77A for storing exhaust gas leaking from between a valve shaft 35 and a second slide bearing 49A is formed between the second slide bearing 49A and the valve shaft 35, and gas exhaust means 78A is provided in the exhaust gas reservoir 77A. The sealing means 5 is connected between the second sliding bearing 49A and the valve shaft 35 outside the exhaust gas reservoir 77A along the axial direction of the valve shaft 35.
7 are provided.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a valve body formed in an exhaust system of an engine by forming a flow passage for exhaust gas, a valve shaft crossing the flow passage, and mounted on the valve shaft in a valve body. A valve body, one end of the valve shaft is rotatably fitted, and a bottomed cylindrical first sliding bearing provided between the valve shaft and the valve body; and the other end of the valve shaft is rotatable. A cylindrical second sliding bearing provided between the valve shaft and the valve body so as to penetrate therethrough, and an actuator for rotating and driving the valve shaft is connected to the other end of the valve shaft protruding from the second sliding bearing. The present invention relates to an exhaust gas valve device for an engine.

[0002]

2. Description of the Related Art Conventionally, such an exhaust gas valve device is already known, for example, from Japanese Patent Laid-Open No. 11-166428.

[0003]

In such an exhaust gas valve device, one end of the valve shaft is supported by the valve body via a first sliding bearing having a bottomed cylindrical shape. Although there is no fear of exhaust gas leakage from between the 1 sliding bearings, there is a fear of exhaust gas leakage from between the valve shaft and the second sliding bearing because the other end of the valve shaft passes through the second sliding bearing.
In the prior art, a seal ring is provided between the valve shaft and the second sliding bearing to prevent the exhaust gas from leaking to the outside.

However, it is difficult to suppress the external leak to almost "0" for a long period of time by securing the reliability of the operation of the valve shaft, that is, the valve body, by the above-described countermeasures against the leak using the seal ring or the like. In particular, exhaust gas valve devices used in exhaust gas purification systems for vehicle engines must comply with increasingly strict exhaust gas regulations, for example, exhaust gas leakage is almost “0” regardless of long-term running of the vehicle at 120K or 150K miles. However, the above-mentioned conventional exhaust gas valve device cannot meet such a demand.

The present invention has been made in view of such circumstances, and has made it possible to suppress exhaust gas leakage to almost "0" for a long period of time while ensuring the operation reliability of a valve shaft with a simple structure. An object of the present invention is to provide an exhaust gas valve device for an engine.

[0006]

In order to achieve the above object, an invention according to claim 1 is characterized in that a valve body provided in the exhaust system of an engine by forming a flow passage for exhaust gas is provided.
A valve shaft traversing the flow passage, a valve body attached to the valve shaft in the valve body, and a bottomed cylindrical shape provided between the valve shaft and the valve body by rotatably fitting one end of the valve shaft. A first sliding bearing, and a cylindrical second sliding bearing provided rotatably penetrating the other end of the valve shaft and provided between the valve shaft and the valve body, wherein the second sliding bearing protrudes from the second sliding bearing. In an exhaust gas valve device for an engine in which an actuator that rotationally drives the valve shaft is connected to the other end of the valve shaft,
An exhaust gas reservoir for storing exhaust gas leaking from between the valve shaft and the second slide bearing is formed between the second slide bearing and the valve shaft or between the second slide bearing and the valve body, and a gas suction means is connected to the exhaust gas reservoir. A sealing means is provided between the valve shaft and the second sliding bearing or the valve body outside the exhaust gas reservoir along the axial direction of the valve shaft.

According to this structure, the exhaust gas leaking from the exhaust gas passage between the valve shaft and the second sliding bearing is temporarily stored in the exhaust gas reservoir, and is discharged from the exhaust gas reservoir by the gas suction means. Since the exhaust gas is sucked, the leakage of the exhaust gas to the outside is suppressed to almost “0”. As a result, the sealing means disposed outside the exhaust gas reservoir may have a function of suppressing suction of air from the outside into the exhaust gas reservoir,
Since it is not required to have a sealing property enough to affect the operation of the valve shaft, a simple structure may be used, and even if deterioration due to long-term use of the sealing means occurs, exhaust gas leaks to the outside. Never. Moreover, it is not necessary to set the inner diameter of the second sliding bearing strictly in consideration of the exhaust gas leakage. That is, a simple structure in which the gas suction means is simply connected to the exhaust gas reservoir formed between the second sliding bearing and the valve shaft or between the second sliding bearing and the valve body. Can be suppressed to almost “0” for a long period of time.

[0008] The invention according to claim 2 provides the above-mentioned claim 1.
In addition to the configuration of the invention described in the above, the gas suction means is characterized in that an intake system of an engine is connected to the exhaust gas reservoir, and according to such a configuration, the gas has leaked between the second sliding bearing and the valve shaft. The exhaust gas is returned to the intake system of the engine, and the number of components for constituting the gas suction means can be reduced.

According to a third aspect of the present invention, in addition to the configuration of the first or second aspect of the present invention, the first and second sliding bearings extend from the valve body while surrounding the outer peripheral surface of the valve shaft. According to this configuration, even if the rust generated on the inner surface of the valve body falls, the rust is formed on the first and second sliding bearings and the bulging cylinder portion that protrudes toward the flow passage. It is possible to prevent the rotation of the valve shaft from being adversely affected by being caught between the valve shafts, and to more reliably guarantee the operation of the valve shaft.

According to a fourth aspect of the present invention, in addition to the configuration of the second aspect, the actuator further comprises:
A negative pressure actuator that operates using a negative pressure generated in an intake system of the engine as a power source, wherein the exhaust gas reservoir is connected to a negative pressure conduit connecting the intake system and the negative pressure actuator, According to this, by sharing the negative pressure conduit of the negative pressure actuator arranged near the exhaust gas reservoir with the gas suction means, it is possible to further suppress the increase in the number of parts.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of the present invention will be described based on embodiments of the present invention shown in the accompanying drawings.

1 to 4 show a first embodiment of the present invention. FIG. 1 is a schematic diagram showing an intake system and an exhaust system of an engine, FIG. 2 is a longitudinal sectional view of an exhaust gas valve device, and FIG. 3 is a sectional view taken along line 3-3 in FIG. 2, and FIG. 4 is a view as seen in the direction of arrow 4 in FIG.

Referring to FIG. 1, an intake system 11 of a multi-cylinder engine E includes an intake pipe 12 having an upstream end connected to an air cleaner (not shown), a surge tank 13 connected to a downstream end of the intake pipe 12, and And an intake manifold 15 connecting between the intake port 14 of the cylinder and the surge tank 13.
A fuel injection valve 16 is mounted in the vicinity. In addition, intake pipe 1
2, a bypass pipe 18 is connected so as to bypass the throttle valve 17 provided in the intake pipe 12.
An air control valve 19 is provided in the bypass pipe 18.

An exhaust system 20 of the engine E includes an exhaust manifold 22 having an upstream end connected to an exhaust port 21 of each cylinder.
A first exhaust pipe 23 commonly connected to a downstream end of the exhaust manifold 22, a catalytic converter 24 connected to a downstream end of the first exhaust pipe 23, and a main exhaust gas capable of guiding exhaust gas passing through the catalytic converter 24. A second exhaust pipe 25 forming a passage 27 and a bypass exhaust gas passage 28 parallel to the main exhaust gas passage 27 are formed.
Exhaust gas case 26 that incorporates 9 and covers second exhaust pipe 25
And an exhaust gas valve device 30 </ b> A for selectively switching the exhaust gas from the catalytic converter 24 to the main exhaust gas passage 27 and the bypass exhaust gas passage 28, and the exhaust gas flowing through the main exhaust gas passage 27 and the bypass exhaust gas passage 28 is It is discharged to the outside via an exhaust muffler not shown.

The HC adsorbent 29 is disposed in the intermediate portion of the bypass exhaust gas passage 28 such that the inner and outer peripheries are supported by the outer surface of the intermediate portion of the second exhaust pipe 25 and the inner surface of the intermediate portion of the exhaust gas case 26. The exhaust gas introduced into the bypass exhaust gas passage 28 flows through the HC adsorbent 29. Further, the second side is located downstream of the position where the HC adsorbent 29 is disposed.
The exhaust pipe 25 is provided with a plurality of communication holes 31 communicating with the downstream end of the bypass exhaust gas passage 28.
Exhaust gas flowing through the adsorbent 29 flows into the communication holes 31, 31.
Through the downstream end of the main exhaust gas passage 27 to the exhaust muffler side.

The HC adsorbent 29 is, for example, a mixture of a crystalline aluminosilicate, more specifically, a mixture of ZSM # 5 zeolite and a catalyst element.
When it is in a low-temperature state, the unburned HC component in the exhaust gas is adsorbed, and the adsorbed unburned HC component is desorbed at 100 ° C to 250 ° C. Note that the adsorption and desorption temperatures of the unburned HC components differ depending on the HC components.

Unburned HC desorbed from the HC adsorbent 29 is provided between the bypass exhaust gas passage 28 upstream of the HC adsorbent 29 and downstream of the throttle valve 17 of the intake system 11.
A return line 32 for returning the components to the intake system 11 is provided. In the return line 32, the valve is opened when the temperature of the HC adsorbent 29 reaches a temperature at which the HC adsorbent 29 desorbs the unburned HC components after the engine E is started. A return control valve 33 is provided.

The exhaust gas valve device 30A keeps the catalytic converter 2 until the predetermined time elapses after the engine E is started.
In order to prevent the unburned HC component from being discharged to the outside due to the catalyst in the catalyst 4 not reaching the activation temperature, the exhaust gas from the catalytic converter 24 is guided to the bypass exhaust gas passage 28, After a lapse of time, the flow of the exhaust gas is switched so that the exhaust gas from the catalytic converter 24 is guided to the main exhaust gas passage 27.

In FIG. 2 to FIG.
0A is a valve body 34 made of cast iron material, a valve shaft 35 rotatably supported by the valve body 34, and valve bodies 36 and 37 mounted on the valve shaft 35 in the valve body 34.
And

The valve body 34 includes the catalytic converter 2
The main flow passage 3 has a downstream end passing through the upstream end and an upstream end of the main exhaust gas passage 27 passing through the downstream end.
8 and a bypass flow passage 39 branched from an intermediate portion of the main flow passage 38 and having a downstream end communicating with an upstream end of the bypass exhaust gas passage 28. The bypass flow passage 39 opens the upstream end of the main exhaust gas passage 38. Thus, the upstream flange portion 40 provided integrally with the valve body 34 is fastened to the catalytic converter 24, and the main exhaust gas passage 38
The downstream end of the bypass exhaust gas passage 39 is opened independently of each other, and the downstream flange portion 41 provided on the valve body 34 is fastened to the second exhaust pipe 25 and the exhaust gas case 26.

In the middle of the main flow passage 38 downstream of the branch position of the bypass flow passage 39, the valve body 34
Is provided with an annular valve seat 42 on the inner surface thereof.
The main flow passage 3 is formed by seating the peripheral portion on the valve seat 42.
8 is formed in a disk shape so as to block the same. An annular valve seat 43 is provided in the valve body 34 at an opening position of the upstream end of the bypass flow passage 39 to the main flow passage 38, and the valve body 37 is configured such that a peripheral portion is seated on the valve seat 43. The bypass flow passage 39 is formed in a disk shape so as to block it. In addition, the valve bodies 37 open the bypass flow path 39 when the main flow path 38 is blocked by the valve element 36, and the valve body 37 blocks the bypass flow path 39. In the state, the valve body 36 is in a state in which the main flow passage 38 is opened, and is connected to each other by the connecting member 44.

At the upstream end of the bypass flow passage 39, a recess 39a recessed toward the main flow passage 38 is formed, and the valve shaft 35 is disposed so as to cross the recess 39a of the bypass flow passage 39. The valve body 37 is fastened to the arm 45 fastened to 35. As a result, the two valve bodies 36 and 37 rotate around the axis of the valve shaft 35 in response to the rotation of the valve shaft 35, and the valve body 36 shuts off the main flow passage 38 and the valve body 37.
Is selectively switched between a state in which the bypass flow path 39 is opened and a state in which the bypass flow path 39 is blocked by the valve element 37 and the valve element 36 opens the main flow path 38.

At the portion corresponding to the valve shaft 35, the valve body 3
4, support holes 46 and 47 extending between the inside and the outside of the valve body 34 are provided coaxially with the valve shaft 35. The support holes 46 and 47 are provided with small-diameter holes 46a and 46a on the bypass flow passage 39 side. Large-diameter holes 46b and 47b are coaxially connected to each other at a step 47a.

A cylindrical bottomed first sliding bearing 48 having a closed outer end is fitted and fixed in the large-diameter hole portion 46b of the support hole 46.
A cylindrical second sliding bearing 49A is fitted and fixed to the large-diameter hole portion 47b of the support hole 47. One end of the valve shaft 35 is rotatably fitted to the first sliding bearing 48, and the other end of the valve shaft 35 rotatably passes through the second sliding bearing 49A. Moreover, the projecting cylinders projecting from the inner surface of the valve body 34 toward the bypass flow passage 39 through the small-diameter holes 46a, 47a of the support holes 46, 47 while surrounding the valve shaft 35 are provided on both the sliding bearings 48, 49A. Parts 50 and 51 are provided integrally.

The second sliding bearing 49A has a small-diameter hole 52, a medium-diameter hole 53 larger in diameter than the small-diameter hole 52, and a large-diameter hole 54 larger in diameter than the medium-diameter hole 53 in this order from the bypass flow passage 39 side. Are provided coaxially, and a flange portion 35a is provided at an intermediate portion of the bearing 35 that penetrates through the second sliding bearing 49A so that the outer peripheral surface faces the inner surface of the medium diameter hole 53.

The other end of the valve shaft 35 projects outward from the second sliding bearing 49A, and the other end of the valve shaft 35 projects radially outward from the outer peripheral surface of the valve shaft 35. A disk-shaped link plate 55 is fixed. A coil-shaped return spring 56 is provided between the link plate 55 and the valve body 34, and the return spring 56
Is seated on the valve seat 43 and the link plate 55 and the valve shaft 35 are rotationally biased in a direction in which the bypass flow passage 39 is shut off.

The second sliding bearing 49 is provided outside the flange 35a.
A sealing means 57 is provided between A and the valve shaft 35, and the sealing means 57 is in contact with the outer surface of the flange 35 a and is a ring-shaped sealing member 58 inserted into the medium diameter hole 53.
A pressing member 59 formed in a ring shape so as to sandwich the seal member 58 between the flange portion 35 a and inserted into the medium-diameter hole 53, and sliding on the outer surface of the valve shaft 35 outside the pressing member 59. A plurality of packings 60 in contact with each other, and a seal holder 85 that holds each packing 60 and is inserted into the large-diameter hole 54 are sandwiched between the link plate 55 and the flange 35a.

In this sealing means 57, the outer surface of the sealing member 58 compressed in the axial direction is in sliding contact with the inner surface of the medium diameter hole 53, and the packings 60 are in sliding contact with the outer surface of the valve shaft 35. The space between the shaft 35 and the second sliding bearing 49A is sealed.

Further, the link plate 55 is formed to have a sufficiently large diameter so as to cover the sealing means 57 from the outside, so that the valve shaft 35 and the sealing means 57 are formed by muddy water or dust scattered as the vehicle travels. Avoid contamination as much as possible,
The operation reliability of the valve shaft 35 can be ensured.

A connecting pin 61 is implanted in the link plate 55 at a position eccentric from the axis of the valve shaft 35, and a negative pressure actuator that rotates the valve shaft 35 against the spring force of the return spring 56. The 62 rod 63 is connected to the connecting pin 61.

The negative pressure actuator 62 includes a casing 64 and a diaphragm 67 whose periphery is sandwiched by the casing 64 so as to partition the inside of the casing 64 into a negative pressure chamber 65 and an atmospheric pressure chamber 66. In addition, a connection pipe 68 communicating with the negative pressure chamber 65 is provided in the casing 64, and a rod 63 connected to the connection pin 61 of the link plate 55 is connected to the center of the diaphragm 67 from the atmospheric pressure chamber 66 side.

Referring to FIG. 1, the connection pipe 68 and the intake system 1
1 is connected to the downstream side of the throttle valve 17 via a negative pressure conduit 69, and in the middle of the negative pressure conduit 69, a negative pressure control for closing the valve after a predetermined time has elapsed from the start of the engine E. A valve 70 is provided. Therefore, when the negative pressure control valve 70 is opened, the intake negative pressure is introduced into the negative pressure chamber 65,
When the diaphragm 67 is bent toward the negative pressure chamber 65, the rod 6
3 operates in the axial direction by rotating the link plate 55. That is, the negative pressure actuator 62
Operates by using a negative pressure generated in the intake system 11 of the engine E as a power source, and operates until a predetermined time elapses after the start of the engine E, thereby opening the bypass flow passage 39 and opening the main flow passage. The valve shaft 35 is rotationally driven to a position at which the valve 38 is shut off.

The casing 64 of the negative pressure actuator 62
Are supported by a support plate 71 fastened to the valve body 34. Moreover, the link plate 55 is provided on the support plate 71.
Are provided in a circular opening 72.

A support frame 73 is fastened to the support plate 71 so as to cover the link plate 55, and an opening sensor 74 is fixed to the support frame 73. The opening sensor 74 has a built-in detection plate 75 having a rotation axis coaxial with the valve shaft 35, and a detection shaft 76 provided on the link plate 55 at a position eccentric from the axis of the valve shaft 35. The detection plate 75 is engaged with a projection 75 a provided on the outer periphery of the detection plate 75. Accordingly, the detection plate 75 rotates in response to the rotation of the valve shaft 35, and the rotation position of the valve shaft 35 is detected by the opening degree sensor 74.

The support plate 71 is provided with a negative pressure actuator 62 and an opening sensor 74 in order to prevent pebbles and the like, which have rebounded as the vehicle travels, from colliding with the negative pressure actuator 62 and the opening sensor 74. A cover 84 that covers from below is fixed.

According to the present invention, an annular exhaust gas reservoir 77A for storing exhaust gas leaking from between the valve shaft 35 and the second slide bearing 49A has an annular recess formed in the inner surface of the intermediate portion of the small diameter hole 52 in the second slide bearing 49A. By providing it, it is formed between the second sliding bearing 49A and the valve shaft 35.

The gas accumulated in the exhaust gas reservoir 77A is sucked by gas suction means 78A. This gas suction means 78A
Is configured such that an exhaust gas reservoir 77A is connected to the intake system 11 downstream of the throttle valve 17, and a passage 79 provided in the second sliding bearing 49A through the exhaust gas reservoir 77A, and a passage 79 through the passage 79. A connection pipe 80 provided in the valve body 34, a portion of the negative pressure conduit 69 closer to the intake system 11 than the negative pressure control valve 70, and a conduit 81 connecting the connection pipes 80, and from the connection position of the conduit 81 to the intake system 11 The exhaust gas reservoir 77 </ b> A is connected to the intake system 11 via the negative pressure conduit 69. In addition, a throttle 82 is provided in the connection pipe 80, and a check valve 86 is provided in the conduit 81.
The check valve 86 is opened to allow only the flow to the intake system 11 when the intake negative pressure of the intake system 11 downstream of the throttle valve 17 is equal to or higher than a predetermined value.
1 to shut off the flow of air from the exhaust gas reservoir 77A to the exhaust gas reservoir 77A. This makes it possible to prevent the backflow of the intake air while eliminating the need for a particularly electrically controlled valve or the like, and exhaust gas leaking from between the valve shaft 35 and the second sliding bearing 49A only when the intake negative pressure is equal to or higher than a predetermined value. Can be effectively returned to the intake system 11.

Next, the operation of the first embodiment will be described. In the exhaust gas valve device 30A, an exhaust gas reservoir 77A for storing the exhaust gas leaking from between the valve shaft 35 and the second slide bearing 49A is formed by the second slide bearing 49A and the second slide bearing 49A. Valve shaft 3
A gas suction means 78A is connected to the exhaust gas reservoir 77A, and a sealing means 57 is provided between the valve shaft 35 and the valve body 34 outside the exhaust gas reservoir 77A along the axial direction of the valve shaft 35. Is provided.

Accordingly, the valve shaft 3 is
Exhaust gas that has leaked through the space between the fifth and second sliding bearings 49A is temporarily stored in the exhaust gas reservoir 77A, and the exhaust gas is sucked from the exhaust gas reservoir 77A by the gas suction means 78A. It can be suppressed to "0". Thus, the sealing means 57 disposed outside the exhaust gas reservoir 77A may have a function of suppressing the suction of air from the outside into the exhaust gas reservoir 77A, and requires a sealing property enough to affect the operation of the valve shaft 35. Since it is not necessary to use a simple structure, the sealing means 5
Even if deterioration occurs due to long-term use of 7, exhaust gas does not leak to the outside. Moreover, it is not necessary to set the inner diameter of the second sliding bearing 49A strictly in consideration of the exhaust gas leakage. That is, a simple structure in which the gas suction means 78A is connected to the exhaust gas reservoir 77A formed between the second sliding bearing 49A and the valve shaft 35, and the leakage of the exhaust gas is increased while ensuring the operation reliability of the valve shaft 35. It can be suppressed to almost “0” over the period.

Further, since the gas suction means 78A is formed by connecting the intake system 11 of the engine E to the exhaust gas reservoir 77A, the exhaust gas leaking between the second sliding bearing 79A and the valve shaft 35 is supplied to the intake system of the engine E. 11, the number of components for constituting the gas suction means 78A can be reduced.

The negative pressure actuator 62 operates using a negative pressure generated in the intake system 11 of the engine E as a power source.
Since the exhaust gas reservoir 77A is connected to the negative pressure conduit 69 connecting between them, the negative pressure conduit 69 of the negative pressure actuator 62 arranged at a position close to the exhaust gas reservoir 77A is shared with the gas suction means 78A, so that parts can be used. An increase in points can be further suppressed.

Further, the first and second sliding bearings 48, 49
A shows the valve body 3 surrounding the outer peripheral surface of the valve shaft 35.
4, a projecting tubular portion 50 projecting toward the bypass flow passage 39,
51 is provided integrally with the first and second sliding bearings 48 and 49A and the valve shaft 35 even if rust generated on the inner surface of the valve body 34 made of cast iron material falls.
Since the overhang is prevented by the overhanging cylindrical portions 50 and 51, the intrusion of rust is prevented from adversely affecting the rotation operation of the valve shaft 35, and the operation of the valve shaft 35 is more reliably guaranteed. can do.

FIG. 5 shows a second embodiment of the present invention, in which parts corresponding to those in the first embodiment are denoted by the same reference numerals.

In the exhaust gas valve device 30B, a cylindrical second sliding bearing 49B is fitted and fixed in the large-diameter hole portion 47b of the support hole 47 provided in the valve body 34, and penetrates through the second sliding bearing 49A. A link plate 55 is fixed to the other end of the bearing 35. Further, the valve shaft 35 is provided with a flange portion 35a for making the outer peripheral surface face the inner surface of the large-diameter hole portion 47b in the support hole 47, and the second sliding bearing 49B and the valve body are provided outside the flange portion 35a. Sealing means 57 is provided between the two.

An annular exhaust gas reservoir 7 for storing exhaust gas leaking from between the valve shaft 35 and the second sliding bearing 49B.
7B is formed between the second sliding bearing 49B and the valve body 34 by providing an annular concave portion on the outer surface of the intermediate portion of the second sliding bearing 49B, and is formed between the flange 35a of the valve shaft 35 and the exhaust gas reservoir 77B. Exhaust gas leaking toward the flange 35a through the space between the valve shaft 35 and the second slide bearing 49B is provided on the outer surface of the two-slide bearing 77B.
A plurality of communication grooves 83 leading to 7B are provided.

The gas collected in the exhaust gas reservoir 77B is sucked by gas suction means 78B. The gas suction means 78B is connected to a connection pipe 80 provided in the valve body 34 through the exhaust gas reservoir 77A, and a negative pressure conduit. 69 (FIG. 1)
A conduit 81 (see FIG. 1) connecting the portion closer to the intake system 11 than the negative pressure control valve 70 and the connection pipe 80, and a negative pressure conduit 69 from the connection position of the conduit 81 to the intake system 11
And the intake system 1 downstream of the throttle valve 17
1 is connected to an exhaust gas reservoir 77A.

According to the second embodiment, the same effects as in the first embodiment can be obtained.

Although the embodiments of the present invention have been described above, the present invention is not limited to the above embodiments, and various design changes can be made without departing from the present invention described in the appended claims. It is possible.

For example, in the above embodiment, the case where the present invention is applied to the exhaust gas purifying apparatus of the engine E has been described. However, the present invention is not limited to such an exhaust gas purifying apparatus. The present invention is widely applicable to valve devices provided in the exhaust system of E.

[0050]

As described above, according to the first aspect of the present invention, it is possible to suppress the leakage of exhaust gas to almost "0" for a long period of time while securing the operation reliability of the valve shaft.

According to the second aspect of the present invention, the number of parts for constituting the gas suction means can be reduced.

According to the third aspect of the present invention, it is possible to prevent rust from being caught between the first and second sliding bearings and the valve shaft and adversely affecting the rotation operation of the valve shaft. It can be guaranteed more reliably.

According to the fourth aspect of the present invention, the negative pressure conduit of the negative pressure actuator disposed near the exhaust gas reservoir is shared with the gas suction means, thereby further suppressing an increase in the number of parts. be able to.

[Brief description of the drawings]

FIG. 1 is a schematic diagram showing an intake system and an exhaust system of an engine.

FIG. 2 is a vertical sectional view of the exhaust gas valve device.

FIG. 3 is a sectional view taken along line 3-3 of FIG. 2;

FIG. 4 is a view taken in the direction of arrow 4 in FIG. 3;

FIG. 5 is a sectional view of the second embodiment corresponding to FIG.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 11 ... Intake system 20 ... Exhaust system 30A, 30B ... Exhaust gas valve device 34 ... Valve body 35 ... Valve shaft 36, 37 ... Valve body 39 ... Bypass flow passage 48 ... · First sliding bearing 49A, 49B ··· Second sliding bearing 50, 51 ··· Overhanging cylinder 57 ··· Sealing means 62 ··· Negative pressure actuator 69 ··· Negative pressure conduit 77A, 77B ··· Exhaust gas storage 78A, 78B: Gas suction means E: Engine

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Takeshi Haga 1-4-1, Chuo, Wako, Saitama Prefecture Inside Honda R & D Co., Ltd. (72) Inventor Tadashi Sato, 1-4-1, Chuo, Wako, Saitama Inside the Honda R & D Co., Ltd. (72) Kazuo Shibuya 1-10 Kiyohakucho, Kuki-shi, Saitama Sony Max Corporation (72) Inventor Junji Morimoto 1-10 Kiyohakucho, Kuki-shi, Saitama Sonymax Corporation F term (reference) 3G065 AA04 AA11 CA12 DA02 DA15 EA01 EA02 FA03 GA41 HA06 HA08 HA10 HA16 KA34 KA37 3G091 AA02 AA23 AA28 AB01 AB10 BA03 BA15 CA12 CA13 CA26 CB07 DA03 DB10 EA20 EA30 FA02 FA04 HA03 A07 FA07 BA21 BA25 BA35 CD03 EA01 EA16

Claims (4)

[Claims] 1. A valve body (34) provided in the exhaust system (20) of an engine (E) by forming a flow passage (39) for flowing exhaust gas, and a valve shaft (30) crossing the flow passage (39). 35), a valve body (36, 37) attached to the valve shaft (35) within the valve body (34), and one end of the valve shaft (35) rotatably fitted to the valve shaft (35). ) And a first cylindrical sliding bearing (48) with a bottom provided between the valve body (34) and the valve shaft (35).
And a second cylindrical sliding bearing (49A, 49B) provided between the valve shaft (35) and the valve body (34) by rotatably penetrating the other end of the second sliding bearing (49).
A, 49B), the other end of the valve shaft (35) protruding from the valve shaft (35) is connected to an actuator (62) for rotationally driving the valve shaft (35).
5) and an exhaust gas reservoir (77A, 77A) for storing exhaust gas leaking from between the second sliding bearings (49A, 49B).
B) is between the second sliding bearing (49A) and the valve shaft (35) or between the second sliding bearing (49B) and the valve body (3).
4) formed between the exhaust gas reservoirs (77A, 77B)
Gas suction means (78A, 78B) is connected to the exhaust gas reservoir (77) along the axial direction of the valve shaft (35).
An exhaust gas valve for an engine, wherein a sealing means (57) is provided outside the second sliding bearing (49A) or the valve body (34) and the valve shaft (35) outside of the second sliding bearing (49A, 77B). apparatus. 2. The gas suction means (78A, 78B).
The exhaust gas valve device for an engine according to claim 1, wherein an intake system (11) of the engine (E) is connected to the exhaust gas reservoir (77A, 77B). 3. The first and second slide bearings (48; 4).
9A, 49B) are provided integrally with projecting tubular portions (50, 51) projecting from the valve body (34) toward the flow passage (39) while surrounding the valve shaft (35). The exhaust gas valve device for an engine according to claim 1 or 2, wherein: 4. The actuator (62) is a negative pressure actuator that operates using a negative pressure generated in an intake system (11) of the engine (E) as a power source, and operates between the intake system (11) and the negative pressure actuator. The exhaust gas valve device according to claim 2, wherein the exhaust gas reservoir (77A, 77B) is connected to a negative pressure conduit (69) connecting the exhaust gas reservoir and the exhaust gas reservoir.