JP2018127946A - Exhaust gas recirculation valve - Google Patents

Abstract

PROBLEM TO BE SOLVED: To increase a flow rate of exhaust gas circulating in valve opening, in an exhaust gas recirculation valve.SOLUTION: In a body 12 constituting an exhaust gas recirculation valve 10, at a lower center, an inlet port 26 to which exhaust gas is supplied is opened, and into the inlet port 26 an annular valve seat 38 is inserted. Then, a sheet part 40 of the valve seat 38 is fixed in a state of being locked to a stage part 48 in the inlet port 26. Also, the valve seat 38 has a leg part 42 on an opening part side of the inlet port 26 with respect to the sheet part 40, and a valve hole 44 on an inner peripheral side of the leg part is formed so as to make its diameter larger than that on the sheet part 40 side and substantially constant.SELECTED DRAWING: Figure 2

Description

  The present invention relates to an exhaust gas recirculation valve, and more particularly to an exhaust gas recirculation valve capable of switching a flow path for recirculating exhaust gas from an exhaust system of an internal combustion engine to an intake system.

  The present applicant uses an exhaust gas recirculation system capable of reducing harmful components such as NOx contained in the exhaust gas by recirculating the exhaust gas discharged from the internal combustion engine to the intake system. An exhaust gas recirculation valve for switching the supply state of the exhaust gas to the intake system has been proposed (see Patent Document 1).

  The exhaust gas recirculation valve connects the body, a guide member for guiding displacement along the axial direction of the valve body in the body, a drive unit that drives the valve body, and the valve body and the drive unit. And a coupling mechanism. The body has an inlet port to which exhaust gas is supplied and an outlet port from which the exhaust gas is discharged. The inlet port is provided with an annular valve seat, and the valve body is seated on the seat surface. Thus, the valve is in a closed state in which the flow of exhaust gas is blocked.

JP 2004-301086 A

  The present invention has been made in connection with the above proposal, and an object thereof is to provide an exhaust gas recirculation valve capable of increasing the flow rate of exhaust gas flowing when the valve is opened.

In order to achieve the above object, the present invention provides a body having a passage and a valve seat through which exhaust gas flows, a housing connected to the body, and an axial direction under an energizing action provided inside the housing. And a movable valve member that is connected to the movable member and opens and closes the passage by being separated from and seated on the valve seat, and the exhaust gas is reopened when the valve body is displaced in a direction away from the body. In the circulation valve,
The valve seat is provided in the inflow port of the body formed in an annular shape and supplied with exhaust gas,
A valve hole formed in the center and penetrating along the axial direction;
A seat part formed on one end side along the axial direction and seated by the valve body;
A rectifying portion formed on the other end side along the axial direction and extending toward the opening side of the inflow port with respect to the sheet portion;
It is characterized by providing.

  According to the present invention, the valve seat is provided at the inlet of the body constituting the exhaust gas recirculation valve, and the valve seat is formed with a seat portion on which the valve body is seated on one end side along the axial direction, On the other end side along the axial direction, a rectifying portion extending toward the opening side of the inlet is formed with respect to the seat portion, and a valve hole penetrates in the center along the axial direction. .

  Therefore, when the valve body is opened away from the seat portion of the valve seat, the clearance between the valve body is suitably controlled by the rectifying portion extending toward the inlet side into which the exhaust gas flows, The exhaust gas flowing between them is preferably rectified. As a result, the flow rate of the exhaust gas flowing from the inlet to the passage can be increased as compared with a conventional exhaust gas recirculation valve that does not have a rectifying part in the valve seat.

  Moreover, it is good to form a rectification | straightening part along the axial direction, and to make the inner peripheral diameter larger than both the inner peripheral diameter of the seating site | part of the valve body in a seat part, and the largest outer periphery diameter of a valve body.

  Further, the upstream end of the rectifying unit has a clearance with the outer peripheral surface of the valve body that is substantially the same as the clearance between the seating site and the outer peripheral surface when the valve body is fully opened. It is good to form.

  Furthermore, the valve body includes a shaft portion connected to the movable member, and a valve portion formed at an end portion of the shaft portion and seatable on the valve seat, and the valve portion is separated from the shaft portion. It is good to form in the taper shape which diameter expands gradually toward it.

  Still further, the valve seat may be fixed in a state in which movement of the valve body is restricted in the displacement direction when the valve body is closed with respect to the inflow port.

  According to the present invention, the following effects can be obtained.

  That is, the valve seat provided at the inflow port of the body is formed on one end side along the axial direction and seated on the valve body, and on the other end side along the axial direction. A rectifying portion extending toward the opening side of the inlet, and when the valve body is opened from the seat portion of the valve seat, the rectifying portion extends toward the inlet side into which the exhaust gas flows. The clearance between the valve body is suitably controlled, and the exhaust gas flowing between the two is suitably rectified. As a result, it is possible to increase the flow rate of the exhaust gas flowing from the inlet to the passage as compared with a conventional exhaust gas recirculation valve that does not have a rectifying part in the valve seat.

1 is an overall cross-sectional view of an exhaust gas recirculation valve according to an embodiment of the present invention. FIG. 2 is an enlarged sectional view showing the vicinity of a valve portion of a valve body in the exhaust gas recirculation valve of FIG. 1. FIG. 3 is an enlarged sectional view showing a valve open state in the exhaust gas recirculation valve of FIG. 2. It is a characteristic curve figure which shows the relationship between the valve opening degree of the valve body in an exhaust gas recirculation valve, and the flow volume of the exhaust gas which distribute | circulates.

  A preferred embodiment of an exhaust gas recirculation valve according to the present invention will be described below and described in detail with reference to the accompanying drawings. In FIG. 1, reference numeral 10 indicates an exhaust gas recirculation valve according to an embodiment of the present invention.

  As shown in FIG. 1, the exhaust gas recirculation valve 10 includes a body 12, a guide portion 16 that is connected to the body 12 and guides the displacement of the valve body 14, and the valve body 14 is pivoted under an energizing action. A drive unit 18 that moves along a direction (arrow A, B direction), a coupling mechanism 22 that connects the plunger (movable member) 20 of the drive unit 18 and the valve body 14, and the axial direction of the valve body 14 And a sensor unit 24 for detecting the opening along the line.

  An inlet port (inlet) 26 that opens at the center of the body 12 and is connected to an exhaust system of an internal combustion engine (not shown) is connected to an intake system of the internal combustion engine that opens away from the inlet port 26. Outlet port 28 is formed. A communication chamber 30 is formed above the inlet port 26 (in the direction of arrow A), and the inlet port 26 and the outlet port are connected via a curved circulation passage (passage) 32 connected to the side of the communication chamber 30. 28 communicates. The communication chamber 30 is formed so as to open from the upper part of the inlet port 26 to the upper surface of the body 12.

  As shown in FIGS. 1 to 3, the inlet port 26 includes a first hole portion 34 formed most below the body 12 (in the direction of arrow B), and above the first hole portion 34 (in the direction of arrow A). The second hole 36 is formed with a reduced diameter, and the second hole 36 is connected to the communication chamber 30. That is, the inlet port 26 is formed in a stepped shape that gradually decreases in diameter toward the communication chamber 30 side (arrow A direction). An annular valve seat 38 is attached to the second hole 36 of the inlet port 26.

  The valve seat 38 is formed in, for example, an annular shape, formed on one end side (in the direction of arrow A) and seated on the valve portion 54 of the valve body 14, and on the other end side of the seat portion 40 ( And a valve hole 44 penetrating along the axial direction (arrows A and B directions) at the center of the seat part 40 and the leg part 42. It is formed.

  The seat portion 40 is formed with a substantially constant outer peripheral diameter, and a valve hole 44 formed on the inner peripheral side is gradually reduced in diameter from one end portion toward the leg portion 42 side (arrow B direction). In other words, the seat portion 40 is formed such that the amount of bulging from the one end portion toward the valve hole 44 side (radially inner side) gradually increases from the other end portion (arrow B direction).

  And the seat surface 46 which the valve part 54 of the valve body 14 mentioned later contact | abuts is formed in the other end part of the sheet | seat part 40 protruded to the innermost radial direction. The sheet surface 46 is formed with the smallest inner peripheral diameter D1 (see FIG. 3) in the sheet portion 40.

  The leg portion 42 is formed with a substantially same outer diameter as that of the seat portion 40, and the inner peripheral diameter D <b> 2 of the valve hole 44 is formed with a constant diameter larger than the valve hole 44 of the seat portion 40. It is formed with a predetermined length along the direction. That is, the valve hole 44 has an inner circumference on the leg portion 42 side (arrow B direction) which is the opening side of the inlet port 26 with respect to the inner circumference diameter D1 of the seat surface 46 which is the seat portion 40 side (arrow A direction). The diameter D2 is formed larger (D1 <D2).

  Further, when the valve element 14 shown in FIG. 3 is fully opened when the valve element 14 shown in FIG. 3 is separated from the seat part 40 and moves most downward (in the direction of arrow B), the leg part 42 and the leg part 42 of the valve element 14 described later are provided. The clearance C2 between the lower end 42a and the clearance C1 between the valve portion 54 and the seat surface 46 is set to be substantially the same length (C1≈C2). That is, the position of the lower end 42 a in the leg portion 42 is appropriately set according to the clearance when the valve body 14 is fully opened.

  The valve seat 38 is inserted so that the outer peripheral surface of the seat portion 40 comes into sliding contact with the inner peripheral surface of the second hole portion 36 from the first hole portion 34 side of the inlet port 26, and one end portion of the seat portion 40 is The second hole 36 and the communication chamber 30 are fixed by welding or the like in a state where the second hole 36 and the communication chamber 30 are engaged with each other. As a result, the valve seat 38 is positioned in the axial direction (arrow A direction) at the inlet port 26.

  Further, the leg portion 42 is accommodated in the first hole portion 34 in the inlet port 26, and an annular space portion 50 is formed between the outer peripheral surface and the first hole portion 34. For example, when the exhaust gas recirculation valve 10 is assembled in the space portion 50, an assembly jig E (refer to a two-dot chain line shape in FIG. 2) is inserted into the space portion 50 along the axial direction. This is used as an inlay hole for positioning. The valve seat 38 is housed in the inlet port 26 and does not protrude in the axial direction (direction of arrow B).

  As shown in FIGS. 1 to 3, the valve body 14 includes, for example, an elongated shaft portion 52, and a valve portion 54 formed at the lower end of the shaft portion 52 and having a diameter increased radially outward. The shaft portion 52 is accommodated so as to extend in the vertical direction (arrow A, B direction) along the center of the body 12, the guide portion 16, and the drive portion 18. In addition, the opening degree of the said valve body 14 is detected by connecting the upper end part of the valve body 14 to the sensor part 24 mentioned later.

  Further, in the middle of the shaft portion 52 along the axial direction, a cutout portion 56 having a diameter reduced radially inward is formed, and a first retainer 92 of the coupling mechanism 22 described later is mounted.

  The valve portion 54 is formed in a triangular section having a diameter that gradually expands radially outward from the lower end portion of the shaft portion 52 (in the direction of arrow B), and has a tapered outer peripheral surface 54a. As shown in FIG. 3, the outer peripheral diameter D3 at the lower end, which is the maximum diameter in the valve portion 54, is larger than the inner peripheral diameter D1 of the seat surface 46 in the valve hole 44 and more than the inner peripheral diameter D2 of the leg portion 42. It is formed small (D1 <D3 <D2). The valve body 14 has the shaft portion 52 and the valve portion 54 inserted through the valve hole 44 of the valve seat 38, and the outer peripheral surface 54 a of the valve portion 54 is seated on or below the seat surface 46 of the seat portion 40. The inlet port 26 is opened and closed by separating. Further, the lower end of the valve portion 54 is disposed so as to face the leg portion 42 of the valve seat 38 in the valve closed state seated on the seat portion 40.

  On the other hand, as shown in FIG. 1, a bottomed housing 58 made of, for example, a metal material is provided on the upper portion of the body 12 and is connected by a bolt 60. The housing 58 is formed, for example, in a cylindrical shape, in which the coupling mechanism 22 and the drive unit 18 are housed, and a holder 64 of the guide unit 16 is formed through a hole 58a opened in the center of the bottom wall. Provided.

  The guide portion 16 is provided between the body 12 and the housing 58, for example, and is provided so as to surround the cylindrical guide body 62 that holds the shaft portion 52 of the valve body 14 and the outer peripheral side of the guide body 62. And a thin plate-like cover 66 sandwiched between the lower surface of the holder 64 and the body 12. The lower end portion of the holder 64 is fixed by being sandwiched between the body 12 and the housing 58.

  A shaft portion 52 of the valve body 14 is inserted in a substantially central portion of the guide body 62 so as to be displaceable, and a cover 66 is formed in a cup shape that bulges downward. Is sandwiched between.

  The drive unit 18 is disposed inside the housing 58 and is provided between the first and second support members 68 and 70 having a substantially cylindrical inner hole, and between the first support member 68 and the second support member 70. It includes a bobbin 74 around which a coil 72 is wound, a sleeve 76 covering the inner peripheral side of the first and second support members 68 and 70, and a plunger 20 provided movably along the inside of the sleeve 76. .

  The first support member 68 extends so as to be substantially orthogonal to the axis of the valve body 14, and extends along the valve body 14, and a first peripheral edge 78 whose end is fixed to the upper portion of the housing 58. It consists of an existing cylindrical first bulging portion 80.

  On the other hand, the second support member 70 extends so as to be substantially orthogonal to the axis of the valve body 14, and has a second peripheral edge 82 whose end is fixed to the lower portion of the housing 58, and along the valve body 14. And a cylindrical second bulging portion 84 facing the first bulging portion 80 of the first support member 68.

  A coil 72 for driving the valve body 14 is disposed in a space surrounded by the first support member 68 and the second support member 70. The coil 72 is electrically connected to a terminal 106, which will be described later, and is wound around a bobbin 74 made of a resin material. The bobbin 74 is held between the first support member 68 and the second support member 70.

  Further, a sleeve 76 formed in a cup shape with a nonmagnetic material is provided on the inner peripheral side of the first support member 68 and the second support member 70, and the shaft portion 52 of the valve body 14 is inserted in the center of the lower end thereof. An insertion hole 86 is formed.

  A cylindrical plunger 20 made of a magnetic material is slidably provided inside the sleeve 76, and the inner peripheral side of the plunger 20 is in the vicinity of the center along the axial direction (directions of arrows A and B). A flange portion 88 projecting inward in the radial direction is formed, and the shaft portion 52 of the valve body 14 is inserted into the flange portion 88.

  A connecting mechanism 22 that connects the plunger 20 and the valve body 14 is provided between the flange portion 88 of the plunger 20 and the cutout portion 56 of the valve body 14.

  The coupling mechanism 22 includes, for example, an annular first spring holder 90 disposed on the upper surface side of the flange portion 88, a first retainer 92 disposed on the lower surface side of the flange portion 88, and the valve body 14. The second retainer 94 is provided below the first retainer 92 in FIG.

  The first spring holder 90 is disposed on the upper surface side of the flange portion 88, and an inner peripheral end and an outer peripheral end thereof are bent upward. A first spring 98 is interposed between the first spring holder 90 and a second spring holder 96 provided in the sensor unit 24. The first spring 98 biases the plunger 20 in a direction in which the plunger 20 is pressed downward (arrow B direction).

  The first retainer 92 is formed in a substantially disk shape having a diameter smaller than that of the plunger 20, and is attached to the notch portion 56 of the valve body 14 through an engagement hole formed in a substantially central portion thereof. A second spring 100 is interposed between the lower surface of the first retainer 92 and the sleeve 76. A third spring 102 is interposed between the second spring 100 and the second retainer 94. Has been. That is, the flange portion 88 of the plunger 20 is clamped under the action of the downward elastic force of the first spring 98 and the upward elastic force of the second spring 100.

  The sensor unit 24 has a sensor case 104 mounted on the upper part of the housing 58, and a sensor unit (not shown) capable of detecting the valve opening degree along the axial direction of the valve body 14 is housed therein. ing. Further, a connector portion 108 that protrudes by a predetermined length and accommodates a terminal 106 is formed on the side of the sensor case 104, and the terminal 106 is connected to the coil 72 through a lead wire (not shown). A coupler connected to a power source (not shown) is connected to the connector unit 108 so that a current from the power source is supplied to the coil 72.

  Further, the valve opening degree of the valve body 14 detected by the sensor unit 24 is converted into a detection signal and output to a controller (not shown) via the terminal 106 of the connector unit 108.

  The exhaust gas recirculation valve 10 according to the embodiment of the present invention is basically configured as described above. Next, the operation and effect of the exhaust gas recirculation valve 10 will be described. In the following description, the valve closed state where the valve portion 54 of the valve body 14 shown in FIG. 1 is seated on the seat portion 40 of the valve seat 38 and the communication between the inlet port 26 and the outlet port 28 is blocked is initially set. This will be described as a state.

  In such a valve closed state shown in FIG. 1, a current is supplied to the coil 72 of the drive unit 18 through the connector unit 108 connected to a power source (not shown), thereby generating a magnetic field under the exciting action of the coil 72 and the plunger. 20 moves downward (in the direction of arrow B) along the inner peripheral surface of the sleeve 76.

  The plunger 20 presses the first retainer 92 through the flange portion 88, whereby the plunger 20 is displaced downward (in the direction of arrow B) while resisting the elastic force of the second spring 100. At that time, the shaft portion 52 of the valve body 14 connected to the first retainer 92 is displaced downward (in the direction of arrow B) under the guide action of the guide portion 16, and as shown in FIG. When the fourteen valve portions 54 are separated from the seat portion 40 of the valve seat 38, the valve is in an open state in which the inlet port 26 and the outlet port 28 are communicated with each other.

  Further, the plunger 20 stops at a position where the downward pressing force generated under the exciting action of the coil 72 balances the elastic force of the second spring 100. That is, the opening / closing amount (valve opening degree) of the valve unit 54 is determined by the amount of current supplied to the coil 72.

  As a result, the exhaust gas supplied from the exhaust system of the internal combustion engine flows from the inlet port 26 to the outlet port 28 through the valve hole 44 of the valve seat 38, the communication chamber 30, and the circulation passage 32, and enters the intake system of the internal combustion engine. Supplied. At this time, as shown in FIG. 3, the exhaust gas suitably flows to the valve hole 44 of the valve seat 38 by flowing along the outer peripheral surface 54 a of the valve portion 54 in the tapered valve body 14. In addition, it has a leg portion 42 extending to the other end side (in the direction of arrow B) with respect to the seat portion 40 of the valve seat 38, and the outer peripheral surface 54a of the valve portion 54 and the seat surface 46 when the valve is opened. Since the clearance C1 between the outer peripheral surface 54a and the clearance C2 between the lower end 42a of the leg portion 42 is substantially the same, the seat portion 40 side passes between the valve hole 44 and the valve portion 54 of the leg portion 42. Is preferably guided to. The clearance C2 described above is between the leg portion 42 and the lower end 42a at which the distance from the valve portion 54 is minimized.

  As a result, as understood from the characteristic curve diagram of FIG. 4 showing the relationship between the valve opening degree of the valve portion 54 with respect to the valve seat 38 and the flow rate of the exhaust gas, the leg portion functioning as the rectifying portion is not provided. First, the characteristic curve L of the present invention is compared with the characteristic curve L ′ (see the broken line in the figure) of the exhaust gas recirculation valve according to the prior art in which the clearance between the valve body and the valve seat becomes large when the valve is opened. In the drawing (see the solid line in the figure), the flow rate of the exhaust gas flowing from the inlet port 26 to the outlet port 28 can be increased by smoothly guiding the exhaust gas to the inlet port 26. In other words, the leg portion 42 is provided on the upstream side of the valve seat 38, and the clearances C1 and C2 between the valve body 14 and the outer peripheral surface 54a are controlled to rectify the exhaust gas flowing between the two, Since it can be led to the port 26, the flow rate can be increased.

  Further, it can be seen that the flow rate of the exhaust gas increases as the valve opening degree of the valve element 14 with respect to the valve seat 38, that is, the downward separation distance increases.

  Next, when the supply of current from the power source (not shown) to the coil 72 is stopped, the plunger 20 is lifted by the elastic force of the second spring 100, and accordingly, the valve body 14 is under the guide action of the guide portion 16. Move upward (arrow A direction). Then, the valve portion 54 of the valve body 14 is seated on the seat portion 40 of the valve seat 38, and the valve is closed with the inlet port 26 closed. When the valve portion 54 is seated on the seat portion 40 of the valve seat 38, a pressing force is applied to the valve seat 38 toward the communication chamber 30 (in the direction of arrow A). Since the movement to the communication chamber 30 side is restricted by the stepped portion 48, the valve seat 38 does not come out of the body 12 and is reliably maintained at a predetermined position of the inlet port 26. Is done. That is, the step portion 48 functions as a stopper for the valve seat 38.

  As described above, in the present embodiment, the valve seat 38 is attached to the inlet port 26 opened in the lower portion of the body 12, and the seat portion 40 on which the valve portion 54 of the valve body 14 is seated is provided. 40 is provided with leg portions 42 extending toward the opening side of the inlet port 26 (in the direction of arrow B). By adopting such a configuration, the valve formed in a tapered shape when the valve portion 54 of the valve body 14 is spaced downward from the seat portion 40 of the valve seat 38 under the drive action of the drive portion 18 is opened. Since the clearances C1 and C2 between the outer peripheral surface 54a of the portion 54 and the seat surface 46 and the lower end 42a of the leg portion 42 can be made substantially the same, the exhaust gas flowing between the two is suitably rectified, Compared with a conventional exhaust gas recirculation valve that does not have, the flow rate of the exhaust gas flowing from the inlet port 26 to the outlet port 28 can be increased.

  In addition, at the inlet port 26, the valve seat 38 is locked by a step portion 48 provided at the boundary between the second hole 36 and the communication chamber 30, and the movement to the communication chamber 30 side (arrow A direction) is restricted. Therefore, even when the valve portion 54 of the valve body 14 is seated from below on the valve seat 38 and an upward pressing force (in the direction of arrow A) is applied, the step portion 48 causes the valve seat 38 to Removal from the inlet port 26 is reliably prevented.

  Further, the inlet port 26 is provided with a space 50 between the inner peripheral surface of the first hole 34 that opens to the lowermost side and the outer peripheral surface 54 a of the valve seat 38. For example, when the housing 58 including the drive unit 18 and the body 12 are assembled, the assembly jig E (see FIG. 2) is inserted into the space 50 and engaged with the inner peripheral surface of the first hole 34. Thus, positioning can be performed reliably, and the assembly jig E can be prevented from coming into contact with the valve seat 38.

  Furthermore, the valve seat 38 is not limited to the case where the seat portion 40 and the leg portion 42 are integrally formed as described above, and the seat portion 40 and the leg portion 42 are separated from each other. You may comprise.

  Furthermore, the seat portion 40 in the valve seat 38 may be formed so that the inner peripheral diameter of the valve hole 44 is constant along the axial direction.

  The exhaust gas recirculation valve according to the present invention is not limited to the above-described embodiment, and can of course have various configurations without departing from the gist of the present invention.

DESCRIPTION OF SYMBOLS 10 ... Exhaust gas recirculation valve 12 ... Body 14 ... Valve body 16 ... Guide part 26 ... Inlet port 30 ... Communication chamber 34 ... 1st hole part 36 ... 2nd hole part 38 ... Valve seat 40 ... Seat part 42 ... Leg part 44 ... Valve hole 48 ... Step part 50 ... Space part 54 ... Valve part 54a ... Outer peripheral surface 58 ... Housing 72 ... Coil

Claims (5)

A body having a passage and a valve seat through which exhaust gas flows, a housing connected to the body, a movable member provided in the housing and moving in the axial direction under energization, and the movable member An exhaust gas recirculation valve that is connected and separated from and seated on the valve seat to open and close the passage, and that opens when the valve body is displaced in a direction away from the body;
The valve seat is provided in an inflow port of the body formed in an annular shape and supplied with the exhaust gas,
A valve hole formed in the center and penetrating along the axial direction;
A seat portion formed on one end side along the axial direction and seated by the valve body;
A rectifying portion formed on the other end side along the axial direction and extending toward the opening side of the inlet with respect to the sheet portion;
An exhaust gas recirculation valve comprising: The exhaust gas recirculation valve according to claim 1,
The rectifying portion extends along the axial direction, and an inner peripheral diameter thereof is formed larger than any of an inner peripheral diameter of a seating portion of the valve body in the seat portion and a maximum outer peripheral diameter of the valve body. An exhaust gas recirculation valve characterized by that. The exhaust gas recirculation valve according to claim 2,
In the fully open state where the valve body is most opened, the clearance between the seating part and the outer peripheral surface is substantially the same as the clearance between the seating portion and the outer peripheral surface. An exhaust gas recirculation valve formed so as to become The exhaust gas recirculation valve according to any one of claims 1 to 3,
The valve body includes a shaft connected to the movable member,
A valve portion that is formed at an end of the shaft portion and is seatable on the valve seat;
Have
The said valve part is an exhaust-gas recirculation valve formed in the taper shape gradually diameter-expanded toward the direction away from the said shaft part. The exhaust gas recirculation valve according to any one of claims 1 to 4,
The exhaust gas recirculation valve, wherein the valve seat is fixed in a state in which movement in a displacement direction when the valve body is closed with respect to the inlet is restricted.

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