JP2008223505A - Fluid control valve - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To prevent trouble of disengagement of first and second abutment ends 11, 12 at one or both ends of a seal ring 9 from a seal ring groove 5 of a valve 3 and coming out. <P>SOLUTION: A flat surface part 71 engaged with end surfaces of first and second engagement projection parts 51, 52 of the seal ring 9 is provided on a part in a valve circumferential direction of a groove bottom surface formation part 7 of the valve 3. The flat surface part 71 is abutted on end surfaces of first and second fitting projection parts 51, 52 of the seal ring 9 to rotation-stop the seal ring 9. Thereby, even if opening/closing action of the valve 3 is performed, the seal ring 9 is not deviated in the valve circumferential direction. Accordingly, since the state that the both first and second abutment ends 11, 12 of the seal ring 9 are restricted between a nozzle 2 and the groove bottom surface formation part 7 of the valve 3 can be maintained for a long period of time, the trouble in which one or both of first and second abutment ends 11, 12 of the seal ring 9 disengage from the seal ring groove 5 of the valve 3 and come out can be certainly prevented. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a fluid control valve that controls fluid flowing through a fluid passage of a housing, and more particularly to an exhaust gas control valve that controls exhaust gas of an internal combustion engine.

[Conventional technology]
Conventionally, for the purpose of reducing harmful substances (for example, nitrogen oxides: NOx, etc.) contained in the exhaust gas of an internal combustion engine such as a diesel engine, EGR gas that is part of the exhaust gas of the internal combustion engine is exhausted. An exhaust gas recirculation device having an exhaust gas recirculation pipe for recirculation from a passage to an intake passage is known.
This exhaust gas recirculation device incorporates an exhaust gas flow rate control valve (EGR gas flow rate control valve: hereinafter referred to as EGRV) that variably controls the flow rate of EGR gas flowing through the exhaust gas recirculation pipe.

  As shown in FIGS. 6 and 7, the EGRV is housed in a housing 101 forming a part of an exhaust gas recirculation pipe and a cylindrical portion (hereinafter referred to as a nozzle) 102 of the housing 101 so as to be freely opened and closed. A disk-shaped valve 103, a shaft 104 that supports and fixes the valve 103, and an actuator that drives the valve 103 via the shaft 104 are provided. An annular seal ring groove 105 extending in the valve circumferential direction is formed on the entire outer peripheral end surface of the valve 103. The seal ring groove 105 is provided on the outer diameter side in the valve radial direction of the groove bottom surface forming portion having a circular cross section in the valve 103. A C-shaped seal ring 109 is fitted in the seal ring groove 105 of the valve 103.

  The seal ring 109 is fitted and held in the seal ring groove 105 so that the seal ring 109 can move in the valve ring radial direction, the valve center axis direction, and the valve circumferential direction in the valve 103. The seal ring 109 is stretched against the inner diameter surface (passage wall surface) of the nozzle 102 by the tension in the diameter increasing direction of the seal ring itself when the valve is fully closed, and a gap between the inner diameter surface of the nozzle 102 and the outer peripheral end surface of the valve 103. By closing the valve, the amount of EGR gas leakage when the valve is fully closed is reduced (see, for example, Patent Documents 1 and 2).

  Further, the seal ring 109 has a notch gap 113 between both the abutting end portions 111 and 112 in the ring circumferential direction of the seal ring 109 in consideration of the assembly property of the valve 103 to the seal ring groove 105. In addition, the EGRV is configured so that the shaft 103 in the axial direction of the shaft 104 is prevented from being directly exposed to the EGR gas when the shaft bearing 114 is slidably supported in the rotational direction via the bearing member when the valve is fully closed. The shaft 104 is held and fixed at the tip end portion (valve mounting portion) in the axial direction of the shaft 104 in a state inclined by a predetermined inclination angle.

[Conventional technical problems]
Here, in the conventionally known EGRV, the position where the inner diameter surface of the nozzle 102 and the sliding surface of the seal ring 109 are always in contact with each other regardless of the change in the operating state of the engine, that is, the difference in the valve opening of the EGRV, It is provided at intervals of 180 ° in the valve circumferential direction.
Then, the nozzle 102 and the seal ring 109 are always in contact with each other, that is, pass through the valve center (O) of the valve 103, and are inclined straightly by a predetermined inclination angle with respect to the rotation axis (A) of the shaft 104. When the seal ring 109 is assembled in the seal ring groove 105 of the valve 103 so that both the joint ends 111 and 112 of the seal ring 109 are arranged on the extending axis (axis in the radial direction of the valve: B). Since both the abutment ends 111 and 112 of the seal ring 109 are restrained by the nozzle 102, one or both of the abutment ends 111 and 112 of the seal ring 109 is not greatly disengaged from the seal ring groove 105 of the valve 103. Absent.

However, in the conventionally known EGRV, the seal ring 109 is displaced in the valve circumferential direction by repeatedly opening and closing the valve 103.
The cause of this is that by repeating the opening and closing operation of the valve 103, a portion that does not contact the inner diameter surface of the nozzle 102 is generated in the seal ring 109, and the seal ring itself rotates due to the tension of the seal ring 109. This is because the joint end portions 111 and 112 are displaced in the valve circumferential direction from the position where they are initially assembled.

Specifically, the seal ring 109 has a tension to suppress an increase in the amount of EGR gas leakage when the valve is fully closed due to the occurrence of a gap with the inner diameter surface of the nozzle 102. When the abutment end 111 (or 112) is out of the position restrained by fitting with the nozzle 102, the tension of the seal ring 109 becomes free and protrudes in the outer peripheral direction, and the restraining force by the nozzle 102 is increased. Opened, the abutment end portion 111 (or 112) is largely pushed out toward the radially outer diameter side of the valve 103.
Thereby, the overlap margin with the seal ring groove 105 is reduced, and one abutting end portion 111 (or 112) of the seal ring 109 is easily detached from the seal ring groove 105. When an external force such as exhaust pulsation pressure acts on the seal ring 109, one abutment end portion 111 (or 112) of the seal ring 109 is completely detached from the seal ring groove 105 and jumps out.

In this case, even if an attempt is made to return the valve 103 from the open state to the valve fully closed position, the one end portion 111 (or 112) of the seal ring 109 is formed in the seal ring groove 105 along the inner diameter surface of the nozzle 102. It cannot be stored, and one abutment end portion 111 (or 112) of the seal ring 109 is sandwiched between the outer peripheral end surface of the valve 103 and the inner diameter surface of the nozzle 102.
Therefore, the seal ring 109 interferes with the inner diameter surface of the nozzle 102, and the valve 103 is in front of the valve fully closed position, so that a further valve closing operation becomes impossible (valve stick) or becomes defective.
Japanese Patent Laying-Open No. 2005-113872 (page 1-18, FIGS. 1-11) JP 2005-233063 A (page 1-15, FIGS. 1-6)

  An object of the present invention is to provide a fluid control valve that can prevent a problem that one or both abutment end portions of a seal ring come off from the outer periphery of the valve and jump out. It is another object of the present invention to provide a fluid control valve that can prevent the valve from being closed or defective.

According to the first aspect of the present invention, the predetermined notch gap is formed between the joint end portions (the end faces) of both (both ends) in the ring circumferential direction of the seal ring.
The valve is provided with a ring detent for restricting the movement of the seal ring in the circumferential direction of the valve so that both the joint ends of the seal ring are constrained by the housing. Even if the opening / closing operation is performed or the opening / closing operation of the valve is repeated a plurality of times, the seal ring does not shift in the valve circumferential direction.

  As a result, the state in which both the joint ends of the seal ring are restrained by the housing is maintained, so that one or both joint ends of the seal ring can be prevented from coming off from the outer periphery of the valve. . Thus, when the valve is closed, one or both abutment end portions of the seal ring are not sandwiched between the outer peripheral end surface of the valve and the passage wall surface of the housing. Therefore, it is possible to prevent the valve from being closed or poorly closed, so that the reliability and durability of the quality of the fluid control valve can be improved.

According to the second aspect of the present invention, the valve is held on the shaft while being tilted by a predetermined inclination angle with respect to the axial direction of the shaft housed in the housing (for example, the shaft housing hole of the shaft bearing portion). It is fixed. As a result, when the valve is fully closed, the inside of the housing (for example, the shaft bearing portion) is not directly exposed to the fluid (for example, high temperature fluid), and the functions of the functional components incorporated in the shaft bearing portion are deteriorated. Absent.
According to the third aspect of the present invention, the ring rotation preventing portion of the valve abuts (or engages or fits) with the end surface of the seal ring, and the seal ring is prevented from rotating. There is no deviation. Thereby, the state where both the joint ends of the seal ring are restrained by the housing can be maintained for a long time.

  According to the fourth aspect of the present invention, the annular circumferential groove extending in the valve circumferential direction is provided on the outer periphery of the valve. The seal ring is fitted in the circumferential groove of the valve. Thus, even if an external force such as exhaust pulsation pressure acts on the seal ring, it is possible to prevent a problem that one or both abutment end portions of the seal ring jump out of the circumferential groove of the valve. Thus, when the valve is closed, one or both abutment ends of the seal ring can be stored in the circumferential groove along the passage wall surface of the housing, so that one or both abutment ends of the seal ring Is not sandwiched between the outer peripheral end surface of the valve and the passage wall surface of the housing. Therefore, it is possible to prevent the valve from being closed or defective.

According to the fifth aspect of the present invention, a flat portion provided in a part of the valve bottom surface forming portion of the groove bottom surface forming portion that forms the groove bottom surface of the valve circumferential groove is employed as the ring detent portion of the valve. ing. The flat surface portion of the groove bottom surface forming portion of the valve abuts (or engages or fits) with the end surface of the opposing portion of the seal ring, and the seal ring is prevented from rotating, whereby the seal ring is displaced in the valve circumferential direction. There is no. Thereby, the state where both the joint ends of the seal ring are restrained by the housing can be maintained for a long time.
According to the sixth aspect of the present invention, a fitting groove provided in a part of the groove bottom surface forming portion in the valve circumferential direction that forms the groove bottom surface of the circumferential groove of the valve is adopted as the ring detent portion of the valve. is doing. The fitting portion of the seal ring is engaged (or fitted) with the fitting groove of the groove bottom surface forming portion of the valve, and the seal ring is prevented from rotating, so that the seal ring is not displaced in the valve circumferential direction. Thereby, the state where both the joint ends of the seal ring are restrained by the housing can be maintained for a long time.

According to the invention of claim 7, as the ring detent portion of the valve, a protrusion provided on a part of the valve bottom surface forming portion of the groove bottom surface forming portion that forms the groove bottom surface of the valve circumferential groove is employed. ing. Then, the protrusion of the groove bottom surface forming portion of the valve abuts (or engages or fits) with the end surface of the fitting portion of the seal ring, and prevents the seal ring from rotating so that the seal ring is displaced in the circumferential direction of the valve. There is nothing. Thereby, the state where both the joint ends of the seal ring are restrained by the housing can be maintained for a long time.
According to an eighth aspect of the present invention, the protrusion is formed integrally with the valve (the groove bottom surface forming portion).

According to the ninth aspect of the present invention, the ring detent portion of the valve is provided with a fitting groove provided in a part of the groove bottom surface forming portion of the groove bottom surface forming portion forming the groove bottom surface of the valve circumferential groove, and A non-rotating pin is press-fitted and fixed in the fitting groove. Then, the rotation prevention pin press-fitted into the fitting groove of the groove bottom surface forming portion of the valve abuts (or engages or fits) with the end surface of the fitting portion of the seal ring, thereby preventing the seal ring from rotating. The seal ring will not be displaced in the valve circumferential direction. Thereby, the state where both the joint ends of the seal ring are restrained by the housing can be maintained for a long time.
According to the invention described in claim 10, the detent pin is formed (manufactured) as a separate body (separate part) from the valve.

According to the eleventh aspect of the invention, the ring detent portion of the valve is provided with a flat portion provided in a part of the valve bottom direction of the groove bottom surface forming portion that forms the groove bottom surface of the circumferential groove of the valve, and this It is comprised by the intermediate member installed between the plane part and the seal ring. Then, the intermediate member installed between the flat portion of the groove bottom surface forming portion of the valve and the seal ring comes into contact with the end surface of the fitting portion of the seal ring to prevent the seal ring from rotating. There is no deviation in the direction. Thereby, the state where both the joint ends of the seal ring are restrained by the housing can be maintained for a long time.
According to the invention described in claim 12, the intermediate member is formed (manufactured) as a separate body (separate part) from the valve. Further, the intermediate member is provided with a detent pin portion that comes into contact with the end surface of the fitting portion of the seal ring.

  The best mode for carrying out the present invention is to prevent a problem that one or both abutment ends of the seal ring come off from the outer periphery of the valve, and prevent the valve from being closed or defective. This is achieved by providing a ring detent for restricting the movement of the seal ring in the valve circumferential direction so that the joint ends of both seal rings are constrained by the housing.

[Configuration of Example 1]
FIGS. 1 to 3 show Embodiment 1 of the present invention. FIGS. 1 and 2 (a) show the entire structure of an exhaust gas flow rate control valve (EGRV), and FIG. FIG. 3 is a view showing a main structure of the EGRV, and FIG. 3 is a view showing a ring detent portion of the EGRV.

  An exhaust gas recirculation device (EGR system) for an internal combustion engine according to the present embodiment is a part of exhaust gas (hereinafter referred to as EGR gas) of an internal combustion engine (hereinafter referred to as engine) such as a diesel engine mounted on a vehicle such as an automobile. ) Is recirculated from the exhaust passage to the intake passage, and an exhaust gas control valve (EGR gas control valve) installed in the middle of the EGR pipe is provided. The EGR gas control valve is an exhaust gas flow rate control valve (EGR gas flow rate control valve: hereinafter referred to as EGRV) that controls the flow rate of exhaust gas flowing through the EGR pipe (the recirculation amount of EGR gas).

The EGRV of the present embodiment corresponds to the fluid control valve of the present invention, and is provided inside a housing 1 hermetically connected in the middle of the EGR pipe and a cylindrical portion (hereinafter referred to as a nozzle) 2 of the housing 1. A disk-shaped valve (EGRV valve body) 3 accommodated in a freely openable / closable manner, a shaft (EGRV valve shaft) 4 for supporting and fixing the valve 3, and an actuator for driving the valve 3 via the shaft 4 ( Valve drive device).
A seal ring groove 5 extending in the valve circumferential direction is formed on the entire outer peripheral end surface of the valve 3. Further, the valve 3 includes a pair of groove side surface forming portions (maximum outer diameter portion having a circular cross section) 6 that forms a seal ring groove side surface (hereinafter abbreviated as a groove side surface) of the seal ring groove 5, and a seal of the seal ring groove 5. A groove bottom surface forming portion 7 having a non-circular cross section for forming a ring groove bottom surface (hereinafter abbreviated as a groove bottom surface) is provided.

  A C-shaped seal ring 9 that can be brought into close contact with the inner diameter surface of the nozzle 2 is fitted in the seal ring groove 5 of the valve 3. The seal ring 9 is fitted into the seal ring groove 5 of the valve 3 so as to surround the periphery of the groove bottom surface forming portion 7 of the valve 3 in the valve circumferential direction. As shown in FIGS. 2B and 3A and 3B, the seal ring 9 expands and contracts due to the difference in thermal expansion coefficient between the nozzle 2 and the seal ring 9. A predetermined notch gap 13 is provided between the abutment end surfaces (abutment) of the first and second abutment end portions 11 and 12 on both sides (both ends) of the seal ring 9 in preparation. That is, the seal ring 9 is cut at one place in the ring circumferential direction.

In the EGRV, exhaust gas passages (fluid passages: hereinafter referred to as EGR gas passages) 14 to 16 that lead EGR gas from the exhaust passage to the intake passage are formed. A bent portion 17 that changes the EGR gas flow direction is provided between the EGR gas passages 15 and 16. The bent portion 17 may not be provided. For example, the EGRV extends straight from the inlet portion (EGR gas introduction port) of the EGR gas passage 14 toward the outlet portion (EGR gas outlet port) of the EGR gas passage 14 along the central axis (C) direction of the nozzle 2. An EGR gas passage may be provided.
Here, the EGRV of the present embodiment changes the EGR gas flow opening area inside the nozzle 2 (EGR gas passage 15) or inside the housing 1 (EGR gas passages 14 and 16), so that the EGR gas is brought into the intake air. An exhaust gas flow rate control valve (fluid flow rate control valve) that variably controls the recirculation amount to be mixed (EGR amount: EGR rate with respect to the new intake air amount) is configured.

  Further, the EGRV is in the state where the valve 3 is closed at the valve fully closed position (when the valve is fully closed), that is, in the central axis (C) direction of the EGR gas passage 15 (or EGR gas passage 14) (EGR gas). When the valve radial axis (B) passing through the valve center (O) of the valve 3 is set on an axis perpendicular to the average flow axial direction of the EGR gas flowing through the passage 15, the seal ring The gap between the passage wall surface of the housing 1 (inner diameter surface of the nozzle 2) and the outer peripheral end surface of the valve 3 is hermetically sealed by using tension in the ring radial direction (diameter expansion direction) orthogonal to the axial direction of 9. It is configured to (seal).

Further, in the EGRV of the present embodiment, the position where the inner diameter surface of the nozzle 2 and the sliding surface of the seal ring 9 are always in contact with each other regardless of the change in the operating state of the engine, that is, the difference in the valve opening of the EGRV, The valves 3 are provided at intervals of 180 ° in the valve circumferential direction.
Further, a coil spring (valve urging means) 18 that urges the valve 3 in the valve closing direction or the valve opening direction is incorporated in the EGRV. The EGRV is equipped with a sensor cover 19 for closing the opening of the outer wall of the housing 1.

The EGRV actuator of this embodiment includes an electric motor that generates a driving force upon receiving electric power, and a power transmission mechanism (this book) for transmitting the rotational movement of the motor shaft (output shaft) of the electric motor to the shaft 4. In the example, a gear reduction mechanism) is provided.
As the electric motor, a direct current (DC) motor such as a brushless DC motor or a brushed DC motor is employed. An alternating current (AC) motor such as a three-phase induction motor may be used.

  The gear reduction mechanism reduces the rotational speed of the motor shaft of the electric motor by two stages so as to achieve a predetermined reduction ratio, and a power transmission mechanism that transmits the motor output shaft torque (driving force) of the electric motor to the shaft 4. Constitute. The gear reduction mechanism includes a pinion gear (motor gear) fixed to the outer periphery of the motor shaft of the electric motor, an intermediate reduction gear that rotates in mesh with the pinion gear, and a final reduction gear (valve gear) 20 that rotates in mesh with the intermediate reduction gear. Etc. are constituted.

A plurality of convex teeth (gear portions) 21 that mesh with the intermediate reduction gear are integrally formed on the outer peripheral surface of the final reduction gear 20. A rotor 22 made of a non-metallic material (resin material) is integrally formed on the inner peripheral portion of the final reduction gear 20. A valve gear plate 23 made of a metal material is insert-molded inside the rotor 22.
Here, the actuator, particularly the electric motor, is configured to be energized and controlled by an engine control unit (hereinafter referred to as ECU).

  The ECU includes functions such as a CPU for performing control processing and arithmetic processing, a storage device (memory such as ROM and RAM) for storing various programs and various data, an input circuit (input unit), an output circuit (output unit), and the like. There is provided a microcomputer having a well-known structure. The microcomputer is connected to a crank angle sensor, an accelerator opening sensor, an air flow meter, a cooling water temperature sensor, an EGR amount sensor 24, and the like. The sensor signals from the various sensors are A / D converted by an A / D converter and then input to a microcomputer built in the ECU.

  When the ignition switch (not shown) is turned on (IG / ON), the ECU detects that the valve opening detected by the EGR amount sensor is based on the control program stored in the memory of the microcomputer. The power supply to the electric motor is feedback-controlled so as to substantially match the control target value set correspondingly. The ECU is configured to forcibly terminate the above control based on the control program stored in the memory when the ignition switch is turned off (IG / OFF).

  The EGR amount sensor 24 is held and fixed to a sensor holding portion provided inside the sensor cover 19. The EGR amount sensor 24 includes a magnet 25 held by the rotor 22 and a Hall IC disposed so as to face the inner peripheral surface of the yoke 26, and how much EGR gas is in the intake air flowing through the intake passage. It detects whether it is mixed, that is, how much the EGR amount to the intake passage is, and outputs it to the ECU. Here, the Hall IC is an IC (integrated circuit) in which a Hall element (non-contact type magnetic detection element) and an amplifier circuit are integrated, and a voltage signal corresponding to a magnetic flux density interlinked with the Hall IC itself. Is output to the ECU. As a non-contact type magnetic detecting element, a Hall element alone or a magnetoresistive element may be used instead of the Hall IC.

The EGRV housing 1 is made of, for example, an aluminum alloy (Al-Cu-Si alloy), a heat-resistant aluminum alloy die-casting or an aluminum alloy-based casting, or a heat-resistant material having excellent high-temperature heat resistance (for example, iron-based casting or cast iron). It is formed in a predetermined shape. The housing 1 is a device (valve housing) that holds the valve 3 in the EGR gas passages 14 to 16 so that the valve 3 can be freely opened and closed (rotated) in the rotational direction from the valve fully closed position to the valve fully open position. Both EGR pipes (or exhaust pipes or intake pipes) arranged at the front and rear are fastened and fixed using fastening bolts.
The housing 1 has an EGR pipe portion in which EGR gas passages 14 to 16 having a circular cross section are formed. The housing 1 has a shaft insertion hole 27 in the vicinity of the bent portion 17 of the EGR pipe portion.

  Then, on the upstream side of the bent portion 17 of the housing 1 and the shaft insertion hole 27 in the EGR gas flow direction, it is attached to an EGR pipe on the exhaust passage side (or a branch portion of the exhaust pipe of the engine, particularly a branch portion of the exhaust manifold). An EGR pipe portion (first cylindrical portion) 31 having a first coupling surface is provided. A cylindrical nozzle fitting portion for fitting and holding the nozzle 2 for protecting the housing 1 from the heat of the EGR gas is provided in a part of the EGR pipe portion 31 (near the valve fully closed position of the valve 3 or front and rear). Is provided. And on the 1st joint surface of the EGR pipe part 31, the inlet side port for introducing EGR gas into the EGR gas passages 14-16 from an exhaust passage is opening.

  Further, on the downstream side of the bent portion 17 of the housing 1 and the shaft insertion hole 27 in the EGR gas flow direction, it is attached to the EGR pipe on the intake passage side (or the merge portion of the intake pipe of the engine, particularly the merge portion of the intake manifold). An EGR pipe portion (second cylindrical portion) 32 having a second coupling surface is provided. In addition, on the second coupling surface of the EGR pipe portion 32, an outlet side port for deriving EGR gas from the EGR gas passages 14 to 16 into the intake passage is opened. That is, the housing 1 of the present embodiment includes an EGR pipe portion 31 in which EGR gas passages 14 and 15 are formed, and an EGR pipe portion 32 in which an EGR gas passage 16 is formed.

A shaft bearing portion 33 that supports the shaft 4 so as to be slidable in the rotation direction is provided inside the housing 1. A shaft housing hole 34 having a circular cross section is provided inside the shaft bearing portion 33 of the housing 1. The shaft accommodation hole 34 communicates with the EGR gas passages 14 to 16 (particularly, the EGR gas passage 15) via the shaft insertion hole 27.
A bearing member (bushing 35, oil seal 36, ball bearing 37, etc.) is fitted and held between the hole wall surface of the shaft housing hole 34 of the housing 1 and the outer periphery of the shaft outer diameter portion of the shaft 4. .

  Then, on the nozzle side of the shaft bearing portion 33, impurities (for example, combustion residues and fine particles such as carbon) contained in the EGR gas that has entered the shaft housing hole 34, for example, EGR using the intake pipe negative pressure. A communication passage 39 is formed for feeding into the exhaust gas recirculation passage in the pipe. The communication passage 39 opens on the second coupling surface disposed opposite to the coupling surface of the intake passage EGR pipe, and is hermetically connected to the intake passage EGR pipe. Further, a motor housing portion 41 that forms a motor housing chamber for holding and fixing the electric motor therein is connected to the shaft bearing portion 33 via a connecting block 40.

  A coil spring 18 and a gear reduction mechanism (pinion gear, intermediate reduction gear, final reduction gear 20, etc.) are provided between the sensor block 19 and the upper side of the connecting block 40 of the housing 1 (the outer wall portion of the housing 1). A gear housing portion 42 forming a gear housing chamber for housing the housing is integrally formed. Further, inside the shaft bearing portion 33 and the connecting block 40, there is provided a cooling water passage 43 through which engine cooling water is circulated and supplied to prevent temperature rise of the housing itself and temperature rise of the electric motor and the bearing member. ing. A plug 44 that closes an opening that is opened when the cooling water passage 43 is formed is connected to a side portion (outer wall portion) of the connecting block 40 of the housing 1.

  The EGRV nozzle 2 forms a part of the EGR pipe and is a cylindrical portion that can open and close the valve 3 and is formed in a circular tube shape by stainless steel or heat resistant steel having excellent high temperature heat resistance. . The nozzle 2 is fitted and held on the inner periphery of the EGR pipe portion 31 of the housing 1 by press fitting or the like. An EGR gas passage 15 that communicates with the combustion chamber for each cylinder of the engine and communicates with the EGR gas passage 14 and the EGR gas passage 16 is formed inside the nozzle 2. Further, a seal ring seat surface to which the seal ring 9 can be in close contact with the valve 3 when the valve 3 is fully closed is provided on the inner diameter surface of the nozzle 2 (the passage wall surface of the housing 1).

  The EGRV of the present embodiment passes through the valve center (O) of the EGRV to prevent the shaft bearing portion 33 and the bearing member of the housing 1 from being directly exposed to EGR gas when the valve is fully closed. One end side of the shaft 4 in the direction of the rotational axis of the shaft 4 using welding means in a state where it is tilted by a predetermined inclination angle with respect to an axis extending straight in the direction (the central axis of the shaft 4, the rotational axis of the shaft 4: A) It uses a swash plate-like valve that is held and fixed to.

  The EGRV valve 3 is formed in a disk shape from a heat-resistant material (for example, stainless steel or heat-resistant steel) having excellent high-temperature heat resistance. The valve 3 is a butterfly valve (rotary valve) that rotates relative to the housing 1 (nozzle 2) to open and close the EGR gas passage 15 (or EGR gas passages 14 and 16). Further, the valve 3 is rotated in the operating range from the valve fully closed position to the valve fully open position based on a control signal from the ECU during engine operation, so that the opening area (exhaust gas) of the EGR gas passage 15 is increased. This is a valve body that variably controls the EGR amount by changing the gas distribution area.

Here, the valve fully closed position is a position where the gap between the passage wall surface of the housing 1 (inner diameter surface of the nozzle 2) and the outer peripheral end surface of the valve 3 is minimum, and the inside of the EGR gas passages 14-16. This is the valve opening (θ = 0 °) at which the EGR amount (EGR gas leakage amount) of the flowing EGR gas is minimized.
The valve fully open position is a position where the gap between the passage wall surface of the housing 1 (inner diameter surface of the nozzle 2) and the outer peripheral end surface of the valve 3 is maximized, and the EGR flows in the EGR gas passages 14-16. This is the valve opening (θ = 70 to 90 °) at which the gas EGR amount is maximized. Details of the valve 3 will be described later.

  The shaft 4 is formed of a heat-resistant material (for example, stainless steel or heat-resistant steel) having excellent high-temperature heat resistance, and is rotatable or slidable inside a shaft receiving hole 34 provided in the shaft bearing portion 33 of the housing 1. It is freely housed. The shaft 4 is a cylindrical metal member that has a circular cross section and is formed straight from the one end side to the other end side in the rotation axis direction. The shaft 4 passes through the shaft insertion hole 27 from the shaft bearing portion 33 of the housing 1 and is inserted into the EGR gas passage 15 (or EGR gas passage 16).

  Further, the shaft 4 has a valve mounting portion 45 for holding and fixing the valve 3 using welding means on one end side in the rotation axis direction. Further, the shaft 4 is integrally provided with a caulking fixing portion 46 for fixing the valve gear plate 23 insert-molded on the inner peripheral portion of the final reduction gear 20 by a fixing means such as caulking on the other end side in the rotation axis direction. Is formed. That is, the final reduction gear 20 is assembled to the other end side of the shaft 4 in the rotation axis direction.

The seal ring 9 is formed in a partial annular shape (C-shape) from a heat-resistant material (for example, stainless steel or heat-resistant steel) having excellent high-temperature heat resistance. The seal ring 9 has a C-shaped circumferential portion 10 extending in the circumferential direction of the ring.
On the radially inner diameter side of the circumferential portion 10 of the seal ring 9, there is provided an inner diameter side end portion that is movably fitted in a seal ring groove 5 formed on the outer circumferential end surface of the valve 3. Further, on the outer diameter side in the radial direction of the circumferential portion 10 of the seal ring 9, there is an outer diameter side end portion protruding to the outer diameter side in the radial direction of the valve 3 from the outer peripheral end surface (valve outer peripheral surface) of the valve 3. Is provided. In other words, the circumferential portion 10 of the seal ring 9 can be moved in the radial direction and the axial direction of the valve in the seal ring groove 5 with the outer diameter side end projecting from the valve outer peripheral end surface. The seal ring groove 5 is fitted and held.

  A pair of seal ring side surfaces are provided on both sides of the circumferential portion 10 of the seal ring 9 in the axial direction (plate thickness direction). In addition, a sliding surface that can be brought into close contact with the inner diameter surface of the nozzle 2 is provided on the end surface on the outer diameter side in the radial direction of the circumferential portion 10 of the seal ring 9 (outer circumferential surface of the seal ring 9). . Further, the end face on the radially inner side of the circumferential portion 10 of the seal ring 9 (inner peripheral surface of the seal ring 9) is at least in contact with the groove bottom surface of the seal ring groove 5 of the valve 3 when the valve 3 is fully closed. A seal ring inner diameter surface is provided opposite to each other with a predetermined groove clearance therebetween.

  Then, one end of the circumferential portion 10 of the seal ring 9 is opposed to the end surface (second opposed surface) of the second joint end portion 12 with a predetermined notch gap (ring circumferential direction distance) 13 therebetween. A first abutment end portion 11 having an end surface (first opposing surface) is provided. A first fitting convex portion (first protrusion) 51 is formed integrally with the first joint end portion 11. The first fitting convex portion 51 is formed from the reference inner diameter surface (the inner diameter surface of the circumferential portion 10 of the seal ring 9 when the valve is fully closed) passing through the inner diameter surface of the circumferential portion 10 of the seal ring 9. It protrudes by a predetermined protrusion amount toward the groove bottom surface side of the groove 5.

  In addition, the other end of the circumferential portion 10 of the seal ring 9 in the ring circumferential direction has a second facing surface that faces the first facing surface of the first joint end portion 11 with a predetermined notch gap 13 therebetween. Two abutment ends 12 are provided. A second fitting protrusion (second protrusion) 52 is formed integrally with the second joint end 12. The second fitting protrusion 52 protrudes from the reference inner diameter surface of the seal ring 9 described above toward the groove bottom surface side of the seal ring groove 5 of the valve 3 by a predetermined protrusion amount.

That is, the first and second fitting convex portions 51 that protrude toward the inner diameter side in the radial direction of the seal ring are formed on both the first and second joint end portions 11 and 12 of the seal ring 9 of the present embodiment. 52 are provided. The first and second fitting convex portions 51 and 52 constitute a facing portion that faces a ring detent portion of the valve 3 described later with a predetermined gap (valve radial direction distance, clearance) therebetween, and the valve 3 With the opening / closing operation, the end surfaces (opposing surfaces) of the two first and second fitting convex portions 51 and 52 come into contact with the ring rotation preventing portion of the valve 3.
Thereby, the seal ring 9 of the present embodiment is restricted from moving in the valve circumferential direction with respect to the valve 3. That is, the seal ring 9 includes two first and second fitting convex portions 51 and 52 provided on the inner peripheral side (near the vicinity) of both the first and second joint end portions 11 and 12 and the ring of the valve 3. The rotation stopper is formed by engaging (or fitting) with the rotation stopper.

  The joint shape of the seal ring 9 may be any of a pad / joint shape, a taper joint shape, and a lap joint shape. Further, a pair of edge portions in the axial direction of the outer surface of the seal ring may be chamfered with a taper shape or an R shape so that the valve 3 can be easily opened and closed. Further, the bent portions (51, 52) are provided by bending the tip portions of the first and second joint end portions 11, 12 of the seal ring 9 substantially at right angles to the groove bottom surface side of the seal ring groove 5. Also good.

Next, details of the valve 3 of this embodiment will be described with reference to FIGS.
As described above, the valve 3 is inclined by a predetermined inclination angle with respect to the rotation axis (A) of the shaft 4 passing through the valve center (O) of the EGRV inside the housing 1. It is a disk-shaped swash plate fixed by welding to the mounting portion 45, and has a disk-shaped portion extending in the valve radial direction from the valve center (O).
An annular outer peripheral edge is integrally provided on the outer diameter side of the disc-shaped portion of the valve 3 in the valve radial direction. In addition, a circular thick portion 61 having a thickness greater than that of the outer peripheral edge is provided on the upstream end face of the disc-like portion. The thick portion 61 is provided in the vicinity of the center of the valve located on the inner diameter side in the valve radial direction from the outer peripheral edge. In addition, a shaft fitting groove 62 is formed on the downstream end face of the disk-like portion to be fitted to one end portion (valve mounting portion 45) of the shaft 4 in the axial direction.

An annular seal ring groove (circumferential groove, annular groove) 5 extending in the circumferential direction of the valve is formed on the entire outer peripheral end surface (entire circumference) of the outer peripheral edge of the valve 3. That is, the seal ring groove 5 is formed continuously in the valve circumferential direction on the entire outer peripheral end surface of the valve 3. A circumferential portion 10 of one seal ring 9 is fitted into the seal ring groove 5.
A pair of groove side surface forming portions 6 that form the groove side surface of the seal ring groove 5 is provided at the outer peripheral edge of the valve 3. The pair of groove side surface forming portions 6 are formed in a disk shape, constitute the maximum outer diameter portion of the valve 3, and are smaller than the outer diameter of the circumferential portion 10 of the seal ring 9.
The disk-shaped portion of the valve 3 is provided with a groove bottom surface forming portion 7 that forms the groove bottom surface of the seal ring groove 5. Most of the outer peripheral surface (groove bottom surface) of the groove bottom surface forming portion 7 is disposed on the reference circumference (the distance from the center point of the disk-shaped portion of the bulb 3 (reference circle radius) is equal). Has been.

  Here, the reference circumference is for the purpose of preventing the seal ring 9 from popping out of the seal ring groove 5, and the valve 3 is opened and the seal ring 9 is displaced to the limit in the diameter expansion direction of itself. Even when the ring center point of the seal ring 9 is greatly decentered with respect to the valve center point of the disc-shaped portion of the valve 3, the inner diameter position of the circumferential portion 10 of the seal ring 9 can be positioned, that is, the seal ring In order to be able to lock the inner diameter surface of the circumferential portion 10 of 9, the position of the groove bottom surface of the seal ring groove 5, that is, the design reference circumference for defining the groove depth of the seal ring groove 5 Thus, it has a predetermined reference circle radius centered on the valve center point of the disc-shaped portion of the valve 3.

The sliding of the inner diameter surface of the nozzle 2 and the seal ring 9 irrespective of a change in the valve circumferential direction of the groove bottom surface forming portion 7 of the valve 3, particularly a change in the operating state of the engine, that is, a difference in the valve opening of the EGRV. A ring detent portion that prevents the seal ring 9 from rotating is provided in the vicinity or front and rear of the position where the surface always contacts.
The ring detent portion of the valve 3 is constituted by a plane portion 71 provided by connecting two adjacent first and second edge portions (ridge lines) 63 and 64 in a straight line with a plane (flat surface). Has been. The flat surface portion 71 is formed on a part of the groove bottom surface forming portion 7 in the valve circumferential direction by a processing technique (for example, cutting) that facilitates processing on the valve side. That is, the flat surface portion 71 is one of the outer peripheral surfaces of the groove bottom surface forming portion 7 (the groove bottom surface of the seal ring groove 5) so as to be lowered by a predetermined depth from the reference circumference of the groove bottom surface forming portion 7. It is provided by cutting a portion (a predetermined arc-shaped range).
The flat portion 71 abuts against the end surfaces of the two first and second fitting convex portions 51 and 52 of the seal ring 9 to prevent the seal ring 9 from rotating. Thus, both the first and second joint end portions 11 and 12 of the seal ring 9 are connected to the inner diameter surface (passage wall surface) of the nozzle 2 of the housing 1 and the outer peripheral surface (seal ring groove) of the groove bottom surface forming portion 7 of the valve 3. The movement of the seal ring 9 in the valve circumferential direction is restricted so as to maintain the state of being restrained with the bottom surface of the groove 5).

Here, maintaining both the first and second joint end portions 11 and 12 of the seal ring 9 between the nozzle 2 of the housing 1 and the groove bottom surface forming portion 7 of the valve 3 means that the engine Regardless of the change in the operating state of the EGRV, that is, the valve opening of the EGRV, the sliding surface of the seal ring 9 is always in contact with the inner diameter surface of the nozzle 2 and the nozzle 2 of the housing 1 This is to maintain the state where the first and second joint end portions 11 and 12 are restrained.
That is, on an axis that extends straight and inclines by a predetermined inclination angle with respect to the rotational axis (A) of the shaft 4 that passes through the valve center (O) of the EGRV (axis B that extends straight in the radial direction of the valve 3). In addition, the first and second joint end portions 11 and 12 of the seal ring 9 are both maintained.
In the seal ring 9 of this embodiment, both the first and second joint end portions 11 and 12 of the seal ring 9 are constrained by the nozzle 2 of the housing 1 in the initial stage of assembly in the seal ring groove 5 of the valve 3. It is assembled at the position.

[Operation of Example 1]
Next, the operation of the exhaust gas recirculation device of this embodiment will be briefly described with reference to FIGS.

When the ignition switch is turned on (IG / ON), the ECU determines that the valve opening (actual EGR amount, actual opening) detected by the EGR amount sensor 24 is the engine operating state, except when the engine is cold started. Feedback control is performed on the power supplied to the electric motor so as to substantially match the control target value (target EGR amount, target opening degree) set corresponding to.
When electric power is supplied to the electric motor, the motor shaft of the electric motor rotates. As a result, the driving force (motor output shaft torque) of the electric motor is transmitted to the pinion gear, the intermediate reduction gear, and the final reduction gear 20. As the final reduction gear 20 rotates, the shaft 4 rotates by a predetermined rotation angle, and the EGRV valve 3 is driven to open from the fully closed position in the valve opening operation direction.

  Therefore, the valve 3 is controlled to open to a valve opening corresponding to the control target value against the urging force of the coil spring 18. As a result, a part of the exhaust gas flowing out from the combustion chamber of each cylinder of the engine (for example, high temperature EGR gas of 500 ° C. or more) is formed in the EGR pipe on the exhaust passage side from the exhaust passage formed in the exhaust pipe. The exhaust gas recirculation passage, the EGR gas passages 14 to 16 formed in the EGRV, and the exhaust gas recirculation passage formed in the EGR pipe on the intake passage side are recirculated to the intake passage formed in the intake pipe. .

On the other hand, when the valve 3 is fully closed, the supply of electric power to the electric motor is stopped or the supply of electric power to the electric motor is restricted. Therefore, the valve 3 is returned to the valve fully closed position by the biasing force (spring load) of the coil spring 18.
As a result, the sliding surface of the seal ring 9 attached to the outer peripheral end surface of the valve 3 sticks to the inner diameter surface of the nozzle 2 due to the tension in the diameter increasing direction of the seal ring itself. It adheres closely to the inner diameter surface.
Therefore, the gap between the outer peripheral end face of the valve 3 and the inner diameter face of the nozzle 2 is completely sealed. As a result, when the valve 3 is held and fixed at the valve fully closed position (when the valve is fully closed), the leakage of EGR gas is reliably suppressed, so that the EGR gas does not enter the intake air.

[Effect of Example 1]
As described above, in the EGRV used in the exhaust gas recirculation apparatus of the present embodiment, the inner diameter surface of the nozzle 2 and the seal ring 9 are not affected by a change in the operating state of the engine, that is, a difference in the valve opening of the EGRV. The positions where the sliding surface always contacts are provided at intervals of 180 ° in the valve circumferential direction of the valve 3.
Then, both seal rings 9 are arranged so as to pass through the valve center (O) and be arranged on an axis (B) extending straight and inclined by a predetermined inclination angle with respect to the rotation axis (A) of the shaft 4. When the first and second joint end portions 11 and 12 are assembled, both the first and second joint end portions 11 and 12 of the seal ring 9 are installed at the position where the nozzle 2 and the seal ring 9 are always in contact with each other. Is done. In this case, since both the first and second joint end portions 11 and 12 of the seal ring 9 are restrained between the nozzle 2 of the housing 1 and the groove bottom surface forming portion 7 of the valve 3, the seal ring 9 One or both of the first and second joint end portions 11 and 12 do not protrude greatly from the seal ring groove 5 of the valve 3.

  Further, in the EGRV valve 3 of this embodiment, both the first and second joint end portions 11 and 12 of the seal ring 9 are restrained between the nozzle 2 of the housing 1 and the groove bottom surface forming portion 7 of the valve 3. In order to maintain this state, a ring detent portion (planar portion 71) that prevents the seal ring 9 from rotating is provided. The flat surface portion 71 of the groove bottom surface forming portion 7 of the valve 3 is one of the circumferential directions of the groove bottom surface forming portion 7 of the valve 3 as shown in FIGS. 2 (a), 3 (a), and 3 (b). Part, especially the position where the inner diameter surface of the nozzle 2 and the sliding surface of the seal ring 9 are always in contact with each other.

  Then, when the valve 3 is opened and closed, the ring rotation preventing portion (flat portion 71) of the valve 3 comes into contact with the front end surfaces of the two first and second fitting convex portions 51 and 52 of the seal ring 9, Even if the valve 3 is opened / closed or the valve 3 is opened / closed a plurality of times by preventing the rotation of the seal ring 9, the seal ring 9 moves against the seal ring groove 5 of the valve 3. There is no deviation in the direction. Therefore, both the first and second joint end portions 11 and 12 of the seal ring 9 are restrained by the nozzle 2 of the housing 1, that is, between the nozzle 2 of the housing 1 and the groove bottom surface forming portion 7 of the valve 3. It is possible to maintain the state restrained by

As a result, even if an external force such as exhaust pulsation pressure acts on the seal ring 9 of the EGRV, one or both of the first and second joint end portions 11 and 12 of the seal ring 9 are connected to the seal ring of the valve 3. It is possible to reliably prevent a problem that it is greatly disengaged from the groove 5 and jumps out. Accordingly, when the valve 3 is operated to be closed, the first and second joint end portions 11 and 12 of one or both of the seal rings are stored in the seal ring groove 5 of the valve 3 along the inner diameter surface of the nozzle 2. Therefore, one or both of the first and second joint end portions 11 and 12 of the seal ring 9 are not sandwiched between the outer peripheral end surface of the valve 3 and the inner diameter surface of the nozzle 2.
Therefore, it is possible to prevent the EGRV valve 3 from being closed (valve stick) or poorly closed, thereby improving the reliability and durability of the EGRV quality (for example, valve operating characteristics with respect to the electric power supplied to the electric motor). can do.

  FIG. 4 shows a second embodiment of the present invention, and is a view showing a ring detent portion of EGRV.

  In the EGRV valve 3 of this embodiment, both the first and second joint end portions 11 and 12 of the seal ring 9 are restrained between the nozzle 2 of the housing 1 and the groove bottom surface forming portion 7 of the valve 3. A ring detent portion for preventing the seal ring 9 from rotating is provided so as to maintain the above state. As shown in FIG. 4A, the ring detent portion of the valve 3 slides between a part of the groove bottom surface forming portion 7 of the valve 3 in the valve circumferential direction, in particular, the inner diameter surface of the nozzle 2 and the seal ring 9. It is the plane part 71 provided in the vicinity or front and back of the position which always contacts a surface. Similar to the first embodiment, the flat portion 71 can be formed on a part of the groove bottom surface forming portion 7 in the valve circumferential direction by a processing technique that facilitates processing on the valve side (for example, cutting).

  Further, as shown in FIG. 4A, the seal ring 9 has a valve 3 in the vicinity of both the first and second joint end portions 11 and 12 and the first and second joint end portions 11 and 12. There are two first and second opposing portions 53 and 54 that face each other with a predetermined gap (valve radial direction distance, clearance) in the ring rotation preventing portion (plane portion 71). These first and second facing portions 53 and 54 have the thickness of the first and second joint end portions 11 and 12 of both the seal rings 9 larger than the circumferential portions 10 of the other seal rings 9. Thick part. The two first and second opposing portions 53 and 54 are directed from the inner diameter surface of the seal ring 9 toward the groove bottom surface side (the inner diameter side in the seal ring radial direction) of the groove bottom surface forming portion 7 of the seal ring groove 5 of the valve 3. It swells to stick out.

  As shown in FIG. 4A, the EGRV of the present embodiment is such that the ring detent portion (the flat portion 71 of the groove bottom surface forming portion 7) of the valve 3 is sealed with the opening / closing operation of the valve 3. 9, the seal ring 9 is displaced in the valve circumferential direction with respect to the seal ring groove 5 of the valve 3 by abutting against the end surfaces of the two first and second opposed portions 53, 54 of 9 and preventing the seal ring 9 from rotating. There is no. As a result, it is possible to maintain a state in which both the first and second joint end portions 11 and 12 of the seal ring 9 are restrained between the nozzle 2 of the housing 1 and the groove bottom surface forming portion 7 of the valve 3 for a long time. Thus, it is possible to reliably prevent a problem that the valve 3 is greatly disengaged from the seal ring groove 5 and jumps out. Further, it is possible to prevent the EGRV valve 3 from being closed (valve stick) or from being poorly closed.

  As shown in FIG. 4 (b), the ring detent portion of the valve 3 of the present embodiment is a part of the groove bottom surface forming portion 7 of the valve 3 in the valve circumferential direction, particularly the inner diameter surface of the nozzle 2 and the seal ring 9. It is the fitting groove 72 provided in the vicinity or front and back of the position which always contacts with the sliding surface. The fitting groove 72 has an outer peripheral surface (groove bottom surface of the seal ring groove 5) of the groove bottom surface forming portion 7 so as to be lowered by a predetermined depth from the reference circumference of the groove bottom surface forming portion 7 of the valve 3. It is provided by drilling or cutting a part of. In the present embodiment, the groove bottom surface of the fitting groove 72 is provided at a position facing the inner diameter surface (inner peripheral surface) of one of the first joint end portions 11 of the seal ring 9. Further, the fitting groove 72 can be formed in a part of the groove bottom surface forming portion 7 in the valve circumferential direction by a processing technique (for example, cutting or the like) that facilitates processing on the valve side.

  Further, as shown in FIG. 4 (b), the seal ring 9 has a fitting portion 55 inserted into the ring detent portion (fitting groove 72) of the valve 3 at one first joint end portion 11 thereof. Have. The fitting portion 55 is formed from the reference inner diameter surface (the inner diameter surface of the circumferential portion 10 of the seal ring 9 when the valve is fully closed) passing through the inner diameter surface of the circumferential portion 10 of the seal ring 9. It protrudes by a predetermined protrusion amount toward the groove bottom side (inner diameter side in the valve radial direction). Further, the bent portion (55) may be provided by bending the distal end portion of the first first end portion 11 of the seal ring 9 substantially at right angles to the groove bottom surface side of the fitting groove 72 of the valve 3.

  In the EGRV of this embodiment, as shown in FIG. 4B, the groove side surface of the ring detent portion (the fitting groove 72 of the groove bottom surface forming portion 7) of the valve 3 is used to open and close the valve 3. Accordingly, the seal ring 9 abuts (engages) the end surface (side surface) of the fitting portion 55 of the seal ring 9 and prevents the seal ring 9 from rotating. There is no deviation in the direction. As a result, it is possible to maintain a state in which the first and second joint end portions 11 and 12 of the seal ring 9 are restrained between the nozzle 2 of the housing 1 and the groove bottom surface forming portion 7 of the valve 3 for a long time. Thus, it is possible to reliably prevent a problem that the valve 3 is greatly disengaged from the seal ring groove 5 and jumps out. In addition, it is possible to prevent the EGRV valve 3 from being closed (valve stick) or from being poorly closed.

As shown in FIG. 4 (c), the ring detent portion of the valve 3 of this embodiment is a part of the groove bottom surface forming portion 7 of the valve 3 in the valve circumferential direction, particularly the inner diameter surface of the nozzle 2 and the seal ring 9. This is a projection (rotation pin part) 73 provided in the vicinity or front and back of the position where the sliding surface of the contact is always in contact. This protrusion 73 is formed on the outer peripheral surface of the groove bottom surface forming portion 7 of the valve 3 (the groove bottom surface of the seal ring groove 5), and the joint end surfaces of the first and second joint end portions 11 and 12 on both (both ends) of the seal ring 9. It protrudes by a predetermined protrusion amount toward the inside, that is, the inside of the notch gap 13 (the outer diameter side in the valve radial direction). Further, the protrusion 73 can be formed on a part of the groove bottom surface forming portion 7 in the valve circumferential direction by a processing technique that facilitates processing on the valve side (for example, cutting).
Moreover, the seal ring 9 of the present embodiment has a notch gap (fitting portion) 13 that is fitted into the ring detent portion (projecting portion 73) of the valve 3, as shown in FIG. .

In the EGRV of this embodiment, as shown in FIG. 4C, the side surface of the ring detent portion of the valve 3 (protrusion portion 73 of the groove bottom surface forming portion 7) is accompanied by the opening / closing operation of the valve 3. The seal ring 9 comes into contact (engagement) with the end face of the notch gap 13 of the seal ring 9, that is, the end face of the first or second joint end portion 11, 12, and prevents the seal ring 9 from rotating. There is no deviation in the valve circumferential direction with respect to the seal ring groove 5 of the valve 3. As a result, it is possible to maintain a state in which the first and second joint end portions 11 and 12 of the seal ring 9 are restrained between the nozzle 2 of the housing 1 and the groove bottom surface forming portion 7 of the valve 3 for a long time. Thus, it is possible to reliably prevent a problem that the valve 3 is greatly disengaged from the seal ring groove 5 and jumps out. In addition, it is possible to prevent the EGRV valve 3 from being closed (valve stick) or from being poorly closed. Further, as shown in FIG. 4C, the seal ring 9 of the present embodiment does not involve a shape change with respect to the conventionally known seal ring 109. Cost reduction.
Further, in this embodiment, as shown in FIGS. 4A to 4C, the ring detent portion (the flat portion 71, the fitting groove 72, and the protruding portion 73) is the groove bottom surface forming portion 7 of the valve 3. Since it is integrally formed, the number of parts is not increased and the cost is reduced.

  FIG. 5 shows a third embodiment of the present invention, and is a view showing a ring detent portion of EGRV.

  In the EGRV valve 3 of this embodiment, both the first and second joint end portions 11 and 12 of the seal ring 9 are restrained between the nozzle 2 of the housing 1 and the groove bottom surface forming portion 7 of the valve 3. A ring detent portion for preventing the seal ring 9 from rotating is provided so as to maintain the above state. As shown in FIG. 5 (a), the ring detent portion of the valve 3 slides between the seal ring 9 and a part of the groove bottom surface forming portion 7 of the valve 3 in the circumferential direction of the valve, particularly the inner diameter surface of the nozzle 2. It has a fitting groove 74 provided in the vicinity or front and back of the position where the surface is always in contact, and a detent pin 75 press-fitted and fixed in the fitting groove 74.

  The fitting groove 74 is formed on the outer peripheral surface of the groove bottom surface forming portion 7 (the groove bottom surface of the seal ring groove 5) so as to be lowered by a predetermined depth from the reference circumference of the groove bottom surface forming portion 7 of the valve 3. It is provided by drilling or cutting a part. In the present embodiment, the groove bottom surface of the fitting groove 74 is provided between the joint end surfaces of the first and second joint end portions 11 and 12 of both (both ends) of the seal ring 9, that is, at a position facing the notch gap 13. ing.

The anti-rotation pin 75 is separated from the groove bottom surface forming portion 7 of the valve 3 so as to have a cylindrical shape (or square shape) by a heat resistant material (for example, stainless steel or heat resistant steel) having excellent high temperature heat resistance. Formed (manufactured). The anti-rotation pin 75 is press-fitted (tightened) or the like into the fitting groove 74 of the valve 3 in a state in which the tip portion protrudes from the outer peripheral surface of the groove bottom surface forming portion 7 of the valve 3 to the outer radial side. Is held by fitting. The rotation prevention pin 75 is connected to the first and second joint end portions 11 and 12 of both (both ends) of the seal ring 9 from the outer peripheral surface of the groove bottom surface forming portion 7 of the valve 3 (the groove bottom surface of the seal ring groove 5). It protrudes by a predetermined amount of protrusion toward the end face of the joint, that is, toward the inside of the notch gap 13 (outer diameter side in the valve radial direction).
Further, as shown in FIG. 5A, the seal ring 9 of the present embodiment has a notch gap (fitting portion) 13 that is fitted into the ring rotation prevention portion (rotation prevention pin 75) of the valve 3. Yes.

  As shown in FIG. 5A, the EGRV of the present embodiment is such that the side surface of the ring detent portion (the detent pin 75) of the valve 3 is notched in the seal ring 9 as the valve 3 opens and closes. The seal ring 9 comes into contact (engagement) with the end face of the gap 13, that is, one of the first and second joint end portions 11 and 12, and prevents the seal ring 9 from rotating. There is no deviation in the circumferential direction of the valve with respect to the groove 5. As a result, it is possible to maintain a state in which the first and second joint end portions 11 and 12 of the seal ring 9 are restrained between the nozzle 2 of the housing 1 and the groove bottom surface forming portion 7 of the valve 3 for a long time. Thus, it is possible to reliably prevent a problem that the valve 3 is greatly disengaged from the seal ring groove 5 and jumps out. In addition, it is possible to prevent the EGRV valve 3 from being closed (valve stick) or from being poorly closed.

  As shown in FIG. 5 (b), the ring detent portion of the valve 3 of this embodiment is a part of the groove bottom surface forming portion 7 of the valve 3 in the valve circumferential direction, particularly the inner diameter surface of the nozzle 2 and the seal ring 9. A flat portion 71 provided in the vicinity or front and back of the position where the sliding surface always contacts, and an intermediate member 76 disposed between the flat portion 71 and the inner diameter surface of the seal ring 9.

The intermediate member 76 is formed as a separate body (separate part) with respect to the groove bottom surface forming portion 7 of the valve 3 so as to have a partial circular shape with a heat resistant material (for example, stainless steel or heat resistant steel) excellent in high temperature heat resistance. (Production). The intermediate member 76 has a detent pin portion (projection portion) 77 that abuts against the end surface of the fitting portion of the seal ring 9. And the rotation prevention pin part 77 is between the joint end surfaces of the 1st, 2nd joint end parts 11 and 12 of both (both ends) of the seal ring 9 from the outer peripheral surface (groove bottom face of the seal ring groove 5) of the intermediate member 76, That is, it protrudes by a predetermined protrusion amount toward the inside of the notch gap 13 (the outer diameter side in the valve radial direction).
Further, as shown in FIG. 5B, the seal ring 9 of the present embodiment has a notch gap (fitting portion) 13 that is fitted into the ring detent portion (rotation pin portion 77) of the valve 3. ing.

  In the EGRV of this embodiment, as shown in FIG. 5B, the side surface of the ring detent portion of the valve 3 (the detent pin portion 77 of the intermediate member 76) is accompanied by the opening / closing operation of the valve 3. The seal ring 9 comes into contact (engagement) with the end face of the notch gap 13 of the seal ring 9, that is, the end face of the first or second joint end portion 11, 12, and prevents the seal ring 9 from rotating. There is no deviation in the valve circumferential direction with respect to the seal ring groove 5 of the valve 3. As a result, the first and second joint end portions 11 and 12 of the seal ring 9 can be maintained for a long time in a state where they are restrained between the nozzle 2 and the intermediate member 76 (or the groove bottom surface forming portion 7). Thus, it is possible to reliably prevent a problem that the valve 3 is greatly disengaged from the seal ring groove 5 and jumps out. In addition, it is possible to prevent the EGRV valve 3 from being closed (valve stick) or from being poorly closed. Further, in this embodiment, by providing the non-rotating pin 75 or the intermediate member 76, the processing on the valve side and the manufacturing on the seal ring side can be handled with an easy processing technique, so the cost is reduced.

[Modification]
In the present embodiment, the actuator (valve driving device) that drives the valve 3 via the shaft 6 is configured by an electric actuator including an electric motor and a power transmission mechanism (for example, a gear reduction mechanism). The actuator that drives the valve via the negative pressure actuator may include a negative pressure actuated actuator including an electromagnetic or electric negative pressure control valve, or an electromagnetic actuator including an electromagnet including a coil.

  In this embodiment, the fluid control valve of the present invention is applied to EGRV that controls the flow rate of exhaust gas (EGR gas, fluid), but the fluid control valve of the present invention is an exhaust that controls the temperature of the exhaust gas. You may apply to a gas control valve. Further, the fluid control valve of the present invention includes an air amount control valve such as a throttle valve that controls the amount of intake air sucked into the engine combustion chamber, and an exhaust gas that controls the flow rate of exhaust gas discharged from the engine combustion chamber. The present invention may be applied to an air flow rate control valve such as a flow rate control valve or an idle rotation speed control valve that controls an intake air amount that bypasses the throttle valve.

  In this embodiment, the fluid control valve of the present invention is applied to a fluid flow control valve such as EGRV. However, the present invention is not limited to such a fluid flow control valve. You may apply to a switching valve and a fluid pressure control valve. Further, the fluid control valve of the present invention may be applied to an intake flow control valve such as a tumble flow control valve or a swirl flow control valve, an intake variable valve that changes the passage length or passage cross-sectional area of the intake passage, and the like. Further, as an internal combustion engine (for example, a traveling engine) mounted on a vehicle such as an automobile, not only a diesel engine but also a gasoline engine may be used.

In the present embodiment, the EGRV is installed in the middle of the EGR pipe, but the exhaust gas (EGR gas) of the internal combustion engine is cooled in the middle of the EGR pipe, for example, upstream or downstream in the EGR gas flow direction from the EGRV. An EGR cooler may be installed.
In this embodiment, the nozzle 2 is fitted and held on the inner periphery of the EGR pipe portion 31 of the housing 1, and the valve 3 is accommodated in the nozzle 2 so as to be opened and closed. The valve 3 may be accommodated directly in the accommodating portion so as to be freely opened and closed. In this case, the nozzle 2 is not necessary, and the number of parts and assembly man-hours can be reduced.

Further, it is not necessary to install the coil spring 18 that urges the EGRV valve 3 in the valve closing direction or the valve opening direction. In this case, the number of parts and assembly man-hours can be reduced. Further, in this embodiment, the housing in which the fluid passage is formed is constituted by the housing 1 connected in the middle of the EGR pipe, but the housing constitutes a part of the intake pipe or a part of the exhaust pipe. You may comprise by a housing.
Further, in this embodiment, the ring detent portion (the flat portion 71, the fitting groove 72, the protrusion 73, and the fitting groove 74) of the valve 3 is formed integrally with the groove bottom surface forming portion 7 of the valve 3. However, the ring anti-rotation portion (the flat portion 71, the fitting groove 72, the protrusion 73, and the fitting groove 74) of the valve 3 is formed as at least one groove side surface of the pair of groove side surface forming portions 6 of the valve 3. It may be formed integrally with the portion 6. In this case as well, it is desirable that the nozzle 2 be provided near or before and after the position where the inner diameter surface of the nozzle 2 and the sliding surface of the seal ring 9 are in constant contact.

  In this embodiment, the ring detent portion of the valve 3 is abutted (or locked, engaged, or fitted) to the first and second joint end portions 11, 12 of both (both ends) of the seal ring 9 or the vicinity thereof. As shown in the figure, a part of the groove bottom surface forming portion 7 of the valve 3 in the circumferential direction of the valve, particularly in the vicinity of the front or back of the position where the inner diameter surface of the nozzle 2 and the sliding surface of the seal ring 9 are always in contact. The ring detent portion of the valve 3 is a portion of the circumferential portion 10 that is shifted by 180 ° in the circumferential direction from the center of the notch gap 13 between the first and second joint end portions 11 and 12 of both (both ends) of the seal ring 9. It may be provided near the position or before and after the position. Also in this case, the ring detent portion of the valve 3 is located at a position where a part of the groove bottom surface forming portion 7 of the valve 3 in the circumferential direction of the valve, particularly the inner diameter surface of the nozzle 2 and the sliding surface of the seal ring 9 are always in contact. It is provided in the vicinity or front and back.

It is sectional drawing which showed the whole structure of EGRV (Example 1). (A) is the fragmentary sectional view which showed the whole structure of EGRV, (b) is the fragmentary sectional view which showed the main structure of EGRV (Example 1). (A) is sectional drawing which showed the ring detent | locking part of EGRV, (b) is an enlarged view of (a) (Example 1). (A)-(c) is sectional drawing which showed the ring detent | locking part of EGRV (Example 2). (A), (b) is sectional drawing which showed the ring detent | locking part of EGRV (Example 3). (A) is sectional drawing which showed the main structure of EGRV, (b) is the fragmentary sectional view which showed the main structure of EGRV (prior art). (A) is explanatory drawing which showed the state in which both the abutment ends of the seal ring were restrained by the inner diameter surface of the nozzle, and (b) one of the abutment ends of the seal ring jumped out of the seal ring groove. It is explanatory drawing which showed the state (prior art).

Explanation of symbols

1 Housing 2 Nozzle (cylindrical part of housing)
3 Valve (EGRV valve body)
4 Shaft (EGRV valve shaft)
5 Seal ring groove (circumferential groove)
6 groove side surface forming portion 7 groove bottom surface forming portion 9 seal ring 11 first abutment end portion of seal ring 12 second abutment end portion of seal ring 13 notch clearance (fitting portion) of seal ring
14 EGR gas passage (fluid passage, exhaust gas passage)
51 1st fitting convex part (opposing part) of seal ring
52 Second fitting convex part (opposite part) of seal ring
53 1st opposing part of a seal ring 54 2nd opposing part of a seal ring 55 Fitting part of a seal ring 71 Flat part (ring detent part) of a groove bottom face forming part
72 Fitting groove (ring detent part) of groove bottom surface forming part
73 Projection of groove bottom surface forming part (ring detent part)
74 Fitting groove (ring detent part) of groove bottom surface forming part
75 Non-rotating pin (ring detent part)
76 Intermediate member 77 Anti-rotation pin part of intermediate member

Claims (12)

(A) a housing having a fluid passage formed therein;
(B) a valve housed in the fluid passage so as to be openable and closable;
(C) In a fluid control valve provided with a seal ring mounted on the outer periphery of the valve and sealing a gap between the passage wall surface of the housing and the outer peripheral end surface of the valve,
The seal ring has a notch gap between both end portions in the circumferential direction of the ring,
The valve has a ring detent portion that restricts movement of the seal ring in the valve circumferential direction so that both joint ends of the seal ring are maintained in a state of being restrained by the housing. A fluid control valve characterized by. The fluid control valve according to claim 1,
A shaft housed inside the housing;
The fluid control valve according to claim 1, wherein the valve is held and fixed to the shaft while being inclined by a predetermined inclination angle with respect to the axial direction of the shaft. The fluid control valve according to claim 1 or 2,
The fluid control valve according to claim 1, wherein the ring detent portion abuts on an end surface of the seal ring to prevent the seal ring from rotating. In the fluid control valve according to any one of claims 1 to 3,
The valve has an annular circumferential groove extending in the circumferential direction of the valve on its outer periphery,
The fluid control valve according to claim 1, wherein the seal ring is fitted in the circumferential groove. The fluid control valve according to claim 4.
The valve has a groove bottom surface forming portion that forms a groove bottom surface of the circumferential groove,
The ring detent portion is a flat portion provided in a part of the groove bottom surface forming portion in the valve circumferential direction,
The seal ring has a facing portion that faces the planar portion,
The fluid control valve according to claim 1, wherein the flat portion abuts against an end surface of an opposing portion of the seal ring to prevent the seal ring from rotating. The fluid control valve according to claim 4.
The valve has a groove bottom surface forming portion that forms a groove bottom surface of the circumferential groove,
The ring detent portion is a fitting groove provided in a part of the groove bottom surface forming portion in the valve circumferential direction,
The seal ring has a fitting portion to be inserted into the fitting groove,
The fluid control valve according to claim 1, wherein the fitting groove engages with a fitting portion of the seal ring to prevent the seal ring from rotating. The fluid control valve according to claim 4.
The valve has a groove bottom surface forming portion that forms a groove bottom surface of the circumferential groove,
The ring detent portion is a protrusion provided on a part of the groove bottom surface forming portion in the valve circumferential direction,
The seal ring has a fitting portion fitted into the protrusion,
The fluid control valve according to claim 1, wherein the protrusion is in contact with an end surface of the fitting portion of the seal ring to prevent the seal ring from rotating. The fluid control valve according to claim 7,
The fluid control valve according to claim 1, wherein the protrusion is formed integrally with the valve. The fluid control valve according to claim 4.
The valve has a groove bottom surface forming portion that forms a groove bottom surface of the circumferential groove,
The ring detent portion has a fitting groove provided in a part of the groove bottom surface forming portion in the valve circumferential direction, and a detent pin fixedly press-fitted into the fitting groove,
The seal ring has a fitting portion to be fitted into the detent pin,
The anti-rotation pin is in contact with an end surface of a fitting portion of the seal ring to prevent the seal ring from rotating. The fluid control valve according to claim 9,
The fluid control valve according to claim 1, wherein the detent pin is formed separately from the valve. The fluid control valve according to claim 4.
The valve has a groove bottom surface forming portion that forms a groove bottom surface of the circumferential groove,
The ring detent portion includes a flat portion provided in a part of the groove bottom surface forming portion in the valve circumferential direction, and an intermediate member installed between the flat portion and the seal ring,
The seal ring has a fitting portion fitted into the intermediate member,
The fluid control valve according to claim 1, wherein the intermediate member abuts against an end surface of a fitting portion of the seal ring to prevent the seal ring from rotating. The fluid control valve according to claim 11.
The fluid control valve according to claim 1, wherein the intermediate member is formed separately from the valve, and has a detent pin portion that comes into contact with an end surface of the fitting portion of the seal ring.

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