JP5690537B2 - Channel open / close valve - Google Patents

Description

  The present invention relates to a flow path opening / closing valve that switches a flow state of a fluid by opening and closing a flow path through which the fluid flows.

  2. Description of the Related Art Conventionally, for example, a channel opening / closing valve that is connected to a fluid flow channel and controls the fluid flow state by switching the communication state of the flow channel is known. In such a channel opening / closing valve, a ball valve is provided inside the valve body, and a shaft connected to an upper portion of the ball valve rotates to form a through hole of the ball valve in the valve body. A pair of passages (gas inlet and gas outlet) communicate with each other. In addition, a fixed seat and a movable seat are provided on the gas inlet side and the gas outlet side of the ball valve so as to sandwich the ball valve, and the movable seat is urged toward the ball valve side by a spring member. The ball valve is held. With this configuration, since the ball valve is always in contact with the fixed seat and the movable seat, sealing performance is ensured (see, for example, Patent Document 1).

JP-A-57-114068

  In the above-described prior art, since the ball valve is always in contact with and sliding with the movable seat and the fixed seat, friction is always generated between these components, and there is a problem of wear and durability of each component. is there. Further, since the ball valve is pressed by the spring member, the pressing load directly affects the vibration resistance.

  In order to cope with such a problem, it can be considered that the fixed seat is omitted and the ball valve is seated on the movable seat only when the valve is closed. Further, in such a configuration, in order to ensure the sealing performance between the movable seat and the ball valve, the movable seat is configured to be displaceable in a direction orthogonal to the axial direction, and the movable seat has an alignment function. It is possible to have it.

  On the other hand, in the case of a flow path opening / closing valve (for example, an EGR valve) that opens and closes a flow path for flowing a gas containing unnecessary materials (for example, combustion products), unnecessary materials are accumulated around the sliding portion of the movable sheet, There is a concern that the slidability is lowered, and as a result, the above-described alignment function of the movable sheet is lowered, so that it is difficult to ensure the sealing performance.

  The present invention has been made in consideration of such circumstances, can reduce wear due to friction between the valve body and the seat, can improve vibration resistance, and further, the valve body and the seat. It is an object of the present invention to provide a flow path opening / closing valve capable of effectively ensuring the sealing performance between the two.

In order to achieve the above object, a flow path opening / closing valve according to the present invention includes a valve body rotatably provided via a shaft, a body main body having a valve chamber that houses the valve body, and the valve body. A movable seat having a seat surface on which the valve seats, wherein the valve body has a spherical shape portion that contacts the seat surface in a valve-closed state, and the shaft has an axis that is the center of curvature of the spherical shape portion A seat-facing portion that faces the movable seat is provided on the opposite side of the valve body from the movable seat with respect to the movable seat . , the sheet first annular side projection with projecting toward the opposite side abuts against the seat face portion is provided, wherein the sheet facing portion, when projecting toward the movable sheet side Tomo Sliding contact second annular side projection is provided to the first annular side protrusion of the movable seat, the sliding portion between the second annular side projection and said first annular side projection, the valve It is located outside the contact portion between the body and the seat surface.

According to said structure, since there is no constant contact with a valve body and a movable sheet | seat, while being able to reduce wear of a valve body and a movable sheet | seat, the influence on vibration resistance can be made small. In addition, the movable sheet and the sheet facing portion are in sliding contact with each other at the end surfaces of the first and second annular side protrusions, and since the sliding area is small, the movable sheet is displaced in a direction perpendicular to the axis. The sliding resistance at the sliding portion can be reduced, and the centering function of the movable sheet can be suitably exhibited. Therefore, it is possible to effectively prevent the occurrence of leak. Furthermore, since the sliding portion between the movable seat and the seat facing portion is outside the contact portion between the valve body and the movable seat in the valve closed state, the movable seat is stably supported by the seat facing portion, and the valve When the body sits on the movable seat, the movable seat does not tilt, and it is possible to effectively prevent the occurrence of leakage.

In the above-described flow path opening / closing valve, the movable sheet side or the sheet facing is disposed at a position inside the first annular side protrusion or the second annular side protrusion and on one of the sheet facing part and the movable sheet. An annular wall portion that protrudes toward the portion side and is close to the other may be provided.

  According to said structure, since an annular wall part functions as a barrier, the gas which flowed in through the gas inflow port cannot reach the inner peripheral side of the said sliding part easily. Therefore, since unnecessary substances contained in the gas are less likely to accumulate on the inner peripheral side of the sliding portion between the movable sheet and the sheet facing portion, the slidability at the sliding portion is more suitably secured.

In the above flow channel opening and closing valve, the outer peripheral portion of the movable sheet may annular outer peripheral projection together when projecting outwardly proximate the inner circumferential surface of the valve chamber is provided.

  According to said structure, since a cyclic | annular outer periphery protrusion functions as a barrier, the gas from the valve body side cannot reach the outer peripheral side of the said sliding part easily. Accordingly, unnecessary substances contained in the gas are less likely to accumulate on the outer peripheral side of the sliding portion between the movable sheet and the sheet facing portion, so that the slidability at the sliding portion is more suitably secured.

In the above flow path opening / closing valve, an inner annular space may be formed between the first annular side protrusion or the second annular side protrusion and the annular wall portion.

  According to the above configuration, the inner labyrinth structure constituted by the inner annular space and the annular wall portion makes it difficult for the gas containing unnecessary materials to reach the inner peripheral side of the sliding portion. It is possible to more effectively suppress the accumulation of unnecessary materials on the inner peripheral side of the.

In the above-described flow path opening / closing valve, it is preferable that an outer annular space is formed between the annular outer peripheral protrusion and the seat facing portion and outside the first annular side protrusion.

  According to the above configuration, the outer labyrinth structure constituted by the outer annular space and the annular outer peripheral projection makes it difficult for the gas containing unnecessary materials to reach the outer peripheral side of the sliding portion. Accumulation of unnecessary substances on the outer peripheral side is more effectively suppressed.

  According to the flow path opening / closing valve according to the present invention, wear due to friction between the valve body and the seat can be reduced, vibration resistance can be improved, and the seal between the valve body and the seat can be improved. The sex can be effectively secured.

It is a partial cross section perspective view of the channel on-off valve concerning one embodiment of the present invention. 2A is a cross-sectional view taken along the line IIA-IIA in FIG. 1, and FIG. 2B is a cross-sectional view showing the ball valve and its peripheral portion in the valve open state. FIG. 3A is a partially omitted enlarged cross-sectional view showing the movable sheet and the sheet facing portion and the peripheral portion thereof in a state where the axes of each other coincide with each other, and FIG. FIG. FIG. 4A is a partially omitted enlarged sectional view showing a first modification of the movable sheet and the sheet facing portion, and FIG. 4B is a partially omitted enlarged sectional view showing a second modified example of the movable sheet and the sheet facing portion. FIG. 4C is a partially omitted enlarged sectional view showing a third modification of the movable sheet and the sheet facing portion, and FIG. 4D is a partially omitted enlarged section showing a fourth modified example of the movable sheet and the sheet facing portion. FIG.

  Hereinafter, preferred embodiments of a flow path opening / closing valve according to the present invention will be described with reference to the accompanying drawings.

  FIG. 1 is a partial cross-sectional perspective view of a flow path opening / closing valve 10 according to an embodiment of the present invention. The flow path opening / closing valve 10 includes a body main body 12, a valve body 14 that is rotatably provided inside the body main body 12, a movable sheet 16 that contacts the valve body 14, and an elastic body that biases the movable sheet 16. 18 and a driving force transmission mechanism 20 that is provided on the upper portion of the body main body 12 and applies a rotational driving force to the valve body 14.

  The flow path opening / closing valve 10 according to the present embodiment is configured as an exhaust gas circulation valve (EGR valve) 10A, and a gas inlet through which exhaust gas containing vaporized fuel is supplied to the lower portion of the body main body 12. 22 is provided, and on the opposite side of the gas inlet 22 with the valve body 14 therebetween, a gas outlet 24 for leading exhaust gas and circulating it to an internal combustion engine (not shown) is provided.

  In the body main body 12, the gas inlet 22 and the gas outlet 24 are provided on a substantially straight line. In the body main body 12, a valve chamber 26 is formed between the gas inlet 22 and the gas outlet 24, and the spherical valve body 14 is rotatably disposed in the valve chamber 26. In the valve body 14, the upper part and the lower part are formed in a planar shape, and the outer peripheral surface of the part excluding the upper part and the lower part is configured as a spherical shape part 30, and the valve body 14 is a part of the spherical shape part 30 ( It contacts the movable sheet 16 at the sealing surface.

  The valve body 14 may not be spherical as a whole as long as the portion (seal surface) that contacts the movable sheet 16 is formed into a spherical surface. For example, the valve body 14 is on the side facing the movable sheet 16. The opposite side may be cut in a flat shape, or may be configured as a disc-shaped valve body having a seal surface in contact with the movable sheet 16 on the outer periphery.

  The upper end portion of the first shaft 32 is connected and fixed to the lower portion of the valve body 14, and the lower end portion of the second shaft 34 is connected and fixed to the upper portion of the valve body 14. The first shaft 32 is supported by a bearing 36 attached and fixed to the lower portion of the body body 12 so as to be rotatable about the axis A1. The second shaft 34 is supported by a bearing 38 attached and fixed to the upper part of the body main body 12 so as to be rotatable about the axis A1. That is, the first shaft 32 and the second shaft 34 rotate around the same axis A1. The axis A1 is parallel to a straight line orthogonal to the axis C of the movable sheet 16.

  Here, in FIG. 1, the axis C of the movable sheet 16 is a straight line that passes through the center of the gas inlet 22 and the center of the gas outlet 24. The arrow X direction is a direction along the axis C, and the arrow Z direction is a direction orthogonal to the X direction and along the axis A1 of the first shaft 32 and the second shaft 34 (the vertical direction in FIG. 1). The arrow Y direction is a direction orthogonal to the X direction and the Z direction.

  The position of the axis A1 of the first shaft 32 and the second shaft 34 is decentered from the axis A2 that is parallel to the axis A1 and passes through the center of curvature of the spherical shape portion 30 (in the case of the substantially spherical valve body 14). Set to position. That is, the axis A1 is set apart from the axis A2 of the valve body 14 by a predetermined distance. Therefore, the valve body 14 is installed in the valve chamber 26 so as to rotate (swing) about the axis A1 set at a position eccentric from the axis A2.

  The driving force transmission mechanism 20 is connected to the above-described second shaft 34, the rotary yoke 40 connected to the upper end portion of the second shaft 34, and the upper portion of the body body 12, and the second shaft 34 via the rotary yoke 40. And a drive source 42 for rotationally driving the motor.

  The upper end portion of the second shaft 34 is inserted through the substantially central portion of the rotary yoke 40 and is fixed by tightening the nut 44. The drive source 42 is composed of, for example, a stepping motor or a rotary actuator that is rotationally driven under an energization action, and the rotational driving force is transmitted to the second shaft 34 via the rotary yoke 40, whereby The connected valve body 14 rotates around the axis A1. In this case, the first shaft 32 connected to the lower portion of the valve body 14 rotates integrally with the valve body 14 under the support action of the bearing 36.

  2A is a cross-sectional view taken along line IIA-IIA in FIG. As shown in FIGS. 1 and 2A, a sheet storage portion 46 constituting a part of the valve chamber 26 is formed between the valve body 14 and the gas inlet 22, and the seat storage portion 46 has a ring. A movable sheet 16 is disposed, a stopper 56 for supporting the elastic body 18 is disposed on the X1 direction side of the movable sheet 16, and a sheet facing portion 58 on which the movable sheet 16 is seated is disposed on the X2 direction side of the movable sheet 16. Has been.

  The movable sheet 16 can be displaced within a range restricted in the direction of the axis C, and is urged by the elastic body 18 to the opposite side (X2 direction side) from the valve body 14. A clearance 47 is provided between the outermost peripheral portion of the movable sheet 16 and the inner peripheral surface of the sheet storage portion 46. Thereby, the movable sheet | seat 16 is arrange | positioned in the body main body 12 so that a displacement in the direction orthogonal to the axis C direction is possible. That is, the movable sheet 16 can be displaced in the YZ plane. By such a displacement function of the movable sheet 16, an alignment function described later is exhibited.

  The movable seat 16 has a communication hole 17 penetrating in the direction of the axis C at the center thereof, and a seat surface 48 on which the valve body 14 is seated is formed on the X1 direction side of the communication hole 17. The seat surface 48 is an annular surface extending about the axis C of the movable sheet 16 and is inclined with respect to the axis C by a predetermined angle. That is, the seat surface 48 is formed so that the inner diameter linearly increases as it goes toward the X1 direction.

  On the outer peripheral portion of the movable sheet 16, an annular outer peripheral protrusion 50 is provided that protrudes outward in the radial direction and extends in the circumferential direction. The outer diameter of the annular outer peripheral projection 50 is set to be smaller than the inner diameter of the sheet storage portion 46, whereby the clearance 47 described above is formed. Further, an outer annular space 49 surrounded by the movable sheet 16, the sheet facing portion 58 and the sheet storage portion 46 is formed on the X2 direction side of the annular outer peripheral protrusion 50.

  A clearance 47 formed between the annular outer peripheral protrusion 50 and the sheet storage portion 46 is a gap extending in an annular shape. When the clearance 47 is set to a small gap that can suppress the inflow of gas from the valve body 14 side to the outer annular space 49 as much as possible within a range in which a movable range for exhibiting the alignment function of the movable sheet 16 can be secured. Good.

  A first annular side protrusion (annular side protrusion) that protrudes in the axis C direction and extends in the circumferential direction on the side surface (X2 direction side) opposite to the side on which the seat surface 48 is provided of the movable sheet 16. 52 is provided. The inner diameter D 2 of the first annular side protrusion 52 is larger than the inner diameter of the communication hole 17, and the outer diameter of the first annular side protrusion 52 is smaller than the outer diameter of the annular outer peripheral protrusion 50. The end surface of the first annular side protrusion 52 is a plane perpendicular to the axis C.

  The stopper 56 in the illustrated example is a ring-shaped member that is fixedly attached to a stopper attachment portion 57 formed on the X1 direction side of the sheet storage portion 46, and an end face on the X2 side on the X1 direction side of the elastic body 18. By abutting against the end portion, the displacement of the elastic body 18 in the direction of the axis C is regulated. The stopper 56 is not limited to the ring shape, and may be configured by a plurality of stopper pieces arranged at intervals in the circumferential direction of the stopper mounting portion 57.

  The elastic body 18 is in contact with the X2 direction side surface of the stopper 56 at the end portion on the X1 direction side, and is in contact with the X1 direction side surface of the annular outer peripheral protrusion 50 of the movable sheet 16 at the X2 direction side end portion. The sheet 16 is elastically biased toward the X2 direction. The elastic body 18 according to the configuration example illustrated in FIG. 1 and the like is configured as a wave washer. This wave washer is a ring-shaped component formed so that the phase in the axial direction differs depending on the position in the circumferential direction, and functions as a spring. The elastic body 18 is not limited to the wave washer, and may be another spring material such as a coil spring, or may be made of a rubber elastic body having a function of urging the movable seat 16 to the side opposite to the valve body 14. Good.

  The sheet facing portion 58 is mounted and fixed to a sheet mounting portion 60 formed on the X2 direction side of the sheet storage portion 46. The sheet facing portion 58 according to one configuration example has a ring shape, and a communication hole 62 penetrating in the axial direction is provided at the center thereof. The communication hole 62 communicates with the communication hole 17 of the movable sheet 16 and constitutes a gas flow path together with the communication hole 17. In the illustrated example, the inner diameter of the communication hole 62 is set to be substantially the same as the inner diameter of the communication hole 17 of the movable sheet 16.

  A second annular side protrusion (annular side protrusion) 64 that protrudes in the axial direction and extends in the circumferential direction is provided on the side of the sheet facing portion 58 on the movable sheet 16 side (X1 direction side). . The inner diameter D3 of the second annular side protrusion 64 is larger than the inner diameter of the communication hole 62, and is substantially the same as the inner diameter D2 of the first annular side protrusion 52 in the illustrated example. The end surface of the second annular side protrusion 64 is a plane perpendicular to the axis C.

  As shown in FIG. 2A, the elastic sheet 18 biases the movable sheet 16 toward the sheet facing portion 58, so that the end surface of the first annular side protrusion 52 contacts the end surface of the second annular side protrusion 64. It touches. As described above, since the predetermined clearance 47 is formed between the outer peripheral portion (annular outer peripheral protrusion 50) of the movable sheet 16 and the sheet storage portion 46, the movable sheet 16 is YZ orthogonal to the axis C. In the plane, the sheet can be displaced while sliding with respect to the second annular side protrusion 64 of the sheet facing portion 58.

  Further, as described above, both the first annular side protrusion 52 and the second annular side protrusion 64 are formed in an annular shape extending in the circumferential direction, and the end surface of the first annular side protrusion 52 and the second annular side are formed. Both end faces of the protrusions 64 are surfaces perpendicular to the axis C. For this reason, the end surfaces are in close contact with each other over the entire circumference in the circumferential direction, whereby a seal is formed between the movable sheet 16 and the sheet facing portion 58.

  As shown in FIG. 2A, an inner diameter D2 of the first annular side protrusion 52 and an inner diameter D3 of the second annular side protrusion 64 are circles drawn by the contact portion 51 between the valve body 14 and the movable seat 16 in the valve closed state ( It is set larger than the diameter D1 of the contact line). Accordingly, the sliding portion 70 between the movable seat 16 and the seat facing portion 58 is outside (radially outward) from the contact portion 51 between the valve body 14 and the movable seat 16 in the valve closed state.

  The sheet facing portion 58 is further provided with an annular wall portion 66 projecting toward the movable sheet 16 and extending in the circumferential direction on the radially inner side of the second annular side protrusion 64 and extending in the circumferential direction. An inner annular space 67 is formed between the side protrusion 64 and the annular wall portion 66. The inner diameter of the annular wall 66 is the same as the inner diameter of the communication hole 62. The outer diameter of the annular wall portion 66 is set smaller than the inner diameters D2 and D3 of the first annular side protrusion 52 and the second annular side protrusion 64.

  The length of the annular wall 66 is such that the position of the end of the annular wall 66 is located closer to the movable sheet 16 (X1 direction side) than the second annular side protrusion 64 and the end of the annular wall 66 is An annular clearance 68 is formed between the movable sheet 16 and the movable sheet 16.

  The clearance 68 is an annularly extending gap. In the illustrated example, the clearance 68 is closer to the valve body 14 side than the sliding portion (contact portion) 70 between the first annular side projection 52 and the second annular side projection 64 (see FIG. X1 direction side). The clearance 68 may be set small enough to suppress the inflow of gas to the inner annular space 67 side as much as possible.

  In the illustrated example, the seat facing portion 58 and the body main body 12 are configured as separate components. However, a shape portion corresponding to the seat facing portion 58 may be integrally formed inside the body main body 12.

  The flow path opening / closing valve 10 according to the present embodiment is basically configured as described above. Next, the operation and effects thereof will be described. Here, as shown in FIG. 1 and FIG. 2A, the valve closed state in which the flow path between the gas inlet 22 and the gas outlet 24 is blocked by the valve body 14 will be described as an initial position.

  As shown in FIG. 2A, the spherical portion 30 provided on the side surface of the valve body 14 is in contact with the seat surface 48 provided on the movable seat 16 at the initial position. That is, the valve body 14 is seated on the movable seat 16 and the communication hole 17 of the movable seat 16 is closed. As described above, the movable seat 16 can be displaced in a direction perpendicular to the direction of the axis C. Therefore, when the valve body 14 is seated on the movable seat 16, there is a deviation caused by a manufacturing error or an assembly error. Even between the valve body 14 and the movable sheet 16, the position of the movable sheet 16 is automatically adjusted. That is, the movable sheet 16 is automatically aligned, and the spherical surface portion 30 and the sheet surface 48 are in close contact with each other in the circumferential direction, so that the sealing performance between them is ensured.

  In addition, the movable sheet 16 is urged toward the sheet facing portion 58 by the elastic body 18, thereby sealing between the movable sheet 16 and the sheet facing portion 58. In this manner, the flow path between the gas inlet 22 and the gas outlet 24 is formed by sealing between the valve body 14 and the movable sheet 16 and between the movable sheet 16 and the sheet facing portion 58. Blocked. Therefore, although a gas (not shown) is supplied to the gas inlet 22, the gas does not flow downstream from the movable sheet 16.

  When the drive source 42 shown in FIG. 1 is driven from such a valve closed state, the rotational driving force of the drive source 42 is transmitted to the second shaft 34 via the rotary yoke 40 and is connected to the second shaft 34. The valve body 14 rotates about the axis A1 set at a position eccentric from the axis A2, and the state shown in FIG. 2B is obtained. Thus, when the valve body 14 rotates around the eccentric axis A1, the valve body 14 is displaced in the direction of retreating with respect to the movable seat 16 (X1 direction).

  In this case, since the movable sheet 16 is urged toward the sheet facing portion 58 by the elastic body 18, the followability of the movable sheet 16 to the valve body 14 is forcibly cut off, and the valve body 14 is moved to the X1 direction side. It moves away from the movable sheet 16 in accordance with the displacement to. As a result, a gap is formed between the movable seat 16 and the valve body 14, and the valve is opened. In such a valve open state, the gas (not shown) supplied to the gas inlet 22 flows through the gap formed between the movable seat 16 and the valve body 14, flows out from the gas outlet 24, and is not shown. Introduced into the institution.

  As described above, according to the flow path opening / closing valve 10 (EGR valve 10A) according to the present embodiment, the valve element 14 rotates (swings) about the eccentric rotation axis, and the valve element 14 is movable. The valve is closed when seated on the seat 16, and the valve is opened when the valve element 14 is separated from the movable seat 16. In such a configuration, the conventional fixed seat is unnecessary, and the valve body 14 is in contact with the movable seat 16 only when the valve seated on the movable seat 16 is in the closed state. Since there is no constant contact between the movable body 16 and the movable seat 16, wear of the valve body 14 and the movable seat 16 can be reduced, and an increase in rotational torque can be prevented.

  Further, when the valve body 14 in the valve-closed state swings away from the movable seat 16, the followability of the movable seat 16 to the valve body 14 is such that the elastic body 18 in the direction opposite to the valve body 14. In particular, when the valve element 14 is separated from the movable sheet 16 without being followed by the movable sheet 16, the wear between the valve element 14 and the movable sheet 16 can be reduced. Furthermore, since the vibration from the movable sheet 16 is not transmitted to the valve body 14 while the valve body 14 is separated from the movable sheet 16, the influence on the vibration resistance can be reduced.

  Furthermore, since the movable seat 16 is disposed so as to be displaceable in a direction perpendicular to the direction of the axis C, when the valve body 14 is seated on the movable seat 16, a deviation caused by a manufacturing error or an assembly error is caused by the valve. Even between the body 14 and the movable sheet 16, the movable sheet 16 can follow the surface of the valve body 14 (spherical shape portion 30) and move in a direction perpendicular to the axis line. Is automatically adjusted. That is, the error can be allowed by the function of aligning the movable sheet 16 being exhibited. For this reason, in the valve closed state, the valve body 14 and the movable sheet | seat 16 contact | adhere reliably, and it can ensure favorable sealing performance.

  By the way, the exhaust gas flowing through the EGR valve 10A contains combustion products (for example, carbon fine particles). When such a combustion product accumulates on the sliding portion 70 between the movable sheet 16 and the sheet facing portion 58, the slidability decreases, and as a result, the alignment function of the movable sheet 16 described above decreases. There is a concern that it is difficult to ensure sealing performance.

  Therefore, in this embodiment, the labyrinth structure is provided on each of the inner peripheral side and the outer peripheral side of the sliding part 70 between the movable sheet 16 and the sheet facing part 58, thereby suppressing gas inflow to the sliding part 70 side. . Thereby, as shown in FIG. 3A, the combustion product 72 is prevented or suppressed from being deposited around the sliding portion 70.

  Specifically, an inner annular space 67 is formed on the inner peripheral side of the sliding portion 70, and an inner wall labyrinth structure 66 is formed on the inner annular space 67. Thus, the gas flow is reduced. The gas G that has flowed in through the inlet accumulates on the inner peripheral surface of the annular wall portion 66, while the annular wall portion 66 prevents or suppresses the inflow to the inner annular space 67 side. Hard to reach the side.

  Further, an outer annular space 49 is formed on the outer peripheral side of the sliding portion 70, and an annular outer peripheral protrusion 50 is provided between the outer annular space 49 and the space on the valve body 14 side, so that an outer labyrinth structure is formed. Therefore, the gas G from the valve body 14 side accumulates on the side surface on the X1 side of the annular outer circumferential protrusion 50, while the annular outer circumferential protrusion 50 prevents or suppresses the flow into the outer annular space 49. It is difficult to reach the outer peripheral portion of the sliding portion 70.

  As described above, since the gas G hardly reaches the inner peripheral side and the outer peripheral side of the sliding portion 70, the combustion products 72 contained in the gas G accumulate on the inner peripheral side and the outer peripheral side of the sliding portion 70. It becomes difficult. Thereby, the sliding property in the sliding part 70 is ensured and the smooth alignment function of the movable sheet | seat 16 is exhibited suitably.

  The movable sheet 16 and the sheet facing portion 58 are not slidably contacted with each other on the entire end surfaces, but are slidably contacted with each other between the end surfaces of the first annular side projection 52 and the second annular side projection 64. The contact area of the sheet facing portion 58 is small. For this reason, the sliding resistance at the sliding portion 70 when the movable sheet 16 is displaced in the direction orthogonal to the axis C (see FIG. 2A, etc.) can be reduced, and the centering function of the movable sheet 16 can be reduced. It can be made to exhibit more suitably.

  In the present embodiment, the clearance 68 formed between the movable sheet 16 and the annular wall portion 66 is located downstream of the sliding portion 70 in the gas G flow direction (valve element 14 side). Therefore, even if the gas G flows into the inner annular space 67 through the clearance 68, the gas G does not flow to the sliding portion 70 side unless the flow direction is reversed. For this reason, it is difficult for the gas G to reach the sliding portion 70 side, and the accumulation of the combustion product 72 is effectively suppressed.

  As described above, since the movable sheet 16 is provided with the first annular side protrusion 52 and the sheet facing portion 58 is provided with the second annular side protrusion 64, the first and second annular side protrusions are provided. Even if the combustion product 72 is accumulated on the outer peripheral side and the inner peripheral side of 52, 64, as shown in FIG. 3B, the first annular side protrusion 52 and the second annular side protrusion 52 each time the movable sheet 16 is displaced. The combustion products 72 can be sheared by sliding the 64 against each other. Therefore, it is possible to effectively prevent the combustion product 72 from being fixed, and as a result, the alignment function of the movable sheet 16 is more suitably exhibited.

  When the first annular side projection 52 and the second annular side projection 64 are provided, depending on the positions of the movable seat 16 and the seat facing portion 58, when the valve body 14 is seated on the movable seat 16, the entire movable seat 16 is inclined. Thus, there is a concern that the sealing performance in the valve closed state is difficult to be secured. Therefore, as shown in FIG. 2A, in the present embodiment, the sliding portion 70 between the movable sheet 16 and the seat facing portion 58 is outside the contact portion 51 between the valve body 14 and the movable seat 16 in the valve closed state. (Radially outward).

  With this configuration, the movable sheet 16 is stably supported by the sheet facing portion 58, and when the valve body 14 is seated on the movable sheet 16, the movable sheet 16 maintains a state in contact with the sheet facing portion 58. 16 does not tilt. Accordingly, the sealing performance between the valve body 14 and the movable seat 16 in the valve closed state is preferably ensured, and the occurrence of leak can be effectively prevented.

  Next, some modified examples of the movable sheet 16 and the sheet facing portion 58 in the above-described flow path opening / closing valve 10 will be described.

  In the flow path opening / closing valve 10, the movable sheet 16 a and the sheet facing portion 58 a shown in FIG. 4A may be employed instead of the movable sheet 16 and the sheet facing portion 58. The movable sheet 16a has a configuration in which the first annular side protrusion 52 in the movable sheet 16 shown in FIG. 2A and the like is replaced with an annular side protrusion 52a that is longer in the axial direction. The sheet facing portion 58a has a configuration in which the second annular side protrusion 64 in the sheet facing portion 58 is eliminated.

  When the configuration shown in FIG. 4A is adopted, the shearing action of the combustion products (see FIG. 3B) cannot be obtained, but the combustion products are slid into the sliding portion 70 in the same manner as the flow path opening / closing valve 10 shown in FIG. The effect of preventing or suppressing the deposition around the periphery of the substrate is obtained. In the configuration shown in FIG. 4A as well, the position of the sliding portion 70 is outside the contact portion 51. Therefore, when the valve body 14 is seated on the movable seat 16a, the movable seat 16a is not inclined and leaks. Can be effectively prevented.

  Further, in the flow path opening / closing valve 10, instead of the movable sheet 16 and the sheet facing portion 58, a movable sheet 16b and a sheet facing portion 58b shown in FIG. 4B may be employed. The movable sheet 16b has a configuration in which the first annular side protrusion 52 in the movable sheet 16 shown in FIG. The sheet facing portion 58b has a configuration in which the second annular side protrusion 64 in the sheet facing portion 58 is replaced with an annular side protrusion 64a that is longer in the axial direction.

  When the configuration shown in FIG. 4B is adopted, the shearing action of the combustion products cannot be obtained, but the combustion products accumulate around the sliding portion 70 as in the flow path opening / closing valve 10 shown in FIG. The effect of preventing or suppressing this is obtained. In the configuration shown in FIG. 4B as well, since the position of the sliding portion 70 is outside the contact portion 51, when the valve body 14 is seated on the movable seat 16b, the movable seat 16b is not tilted and leaks. Can be effectively prevented.

  Further, instead of the movable sheet 16 and the sheet facing portion 58 in the flow path opening / closing valve 10, a movable sheet 16c and a sheet facing portion 58c shown in FIG. 4C may be employed. The movable sheet 16c has a configuration in which an annular wall portion 66a protruding toward the sheet facing portion 58c is added to the movable sheet 16 shown in FIG. 2A and the like. The sheet facing portion 58c has a configuration in which the annular wall portion 66 in the sheet facing portion 58 is eliminated. That is, the configuration shown in FIG. 4C is a configuration in which the annular wall portion 66 is rearranged from the seat facing portion 58 side to the movable seat 16 side in the configuration shown in FIG. 2A and the like.

  Even when the configuration shown in FIG. 4C is adopted, substantially the same operational effects as those of the flow path opening / closing valve 10 shown in FIG. 2A and the like can be obtained. 4C, since the position of the sliding portion 70 is outside the contact portion 51, the movable seat 16c is not tilted when the valve body 14 is seated on the movable seat 16c, and the leakage is prevented. Can be effectively prevented. In the configuration shown in FIG. 4A or 4B, the annular wall portion 66 provided on the sheet facing portion 58a, 58b side may be rearranged on the movable sheet 16 side.

  Moreover, it may replace with the sheet | seat opposing part 58 in the flow-path on-off valve 10, and may employ | adopt the sheet | seat opposing part 58d shown to FIG. 4D. The sheet facing portion 58d has a configuration in which the annular wall portion 66 in the sheet facing portion 58 shown in FIG. The movable sheet 16 in contact with the sheet facing portion 58d is the same as the movable sheet 16 shown in FIG.

  When the configuration shown in FIG. 4D is adopted, the annular wall portion 66 is not provided, so that combustion products are likely to accumulate on the inner peripheral side of the sliding portion 70. However, the combustion products are generated by the above-described shearing action (see FIG. 3B). Since it can be sheared, sticking of combustion products can be effectively prevented. 4D, the position of the sliding portion 70 is outside the contact portion 51. Therefore, when the valve body 14 is seated on the movable seat 16, the movable seat 16 does not tilt and leaks. Can be effectively prevented.

  The present invention is not limited to the EGR valve, and can be applied to other flow path opening / closing valves that open and close a flow path for flowing a gas containing unnecessary substances such as combustion products.

  In the above description, the present invention has been described with reference to preferred embodiments. However, the present invention is not limited to the above-described embodiments, and various modifications can be made without departing from the scope of the present invention. Needless to say.

DESCRIPTION OF SYMBOLS 10 ... Flow path on-off valve 10A ... EGR valve 12 ... Body main body 14 ... Valve body 16, 16a, 16b, 16c ... Movable seat 17 ... Communication hole 22 ... Gas inlet 24 ... Gas outlet 26 ... Valve chamber 30 ... Spherical shape 48: sheet surface 52, 52a ... first annular side protrusion 58, 58a-58d ... sheet facing part 64, 64a ... second annular side protrusion 66, 66a ... annular wall

Claims (5)

A valve body rotatably provided via a shaft;
A body body having a valve chamber for accommodating the valve body;
A movable seat having a seat surface on which the valve body is seated,
The valve body has a spherical shape portion that comes into contact with the seat surface in a valve closed state,
The shaft is attached to the valve body at a position where the axis thereof deviates from the center of curvature of the spherical shape portion,
In the body body, on the side opposite to the valve body with respect to the movable sheet, a sheet facing portion facing the movable sheet is provided,
Wherein the movable sheet, the first annular side projection to abut against the seat facing portion with projecting toward the seat face portion side is provided,
The sheet facing portion is provided with a second annular side protrusion that protrudes toward the movable sheet side and slidably contacts the first annular side protrusion of the movable sheet,
The sliding portion between the first annular side protrusion and the second annular side protrusion is located outside the contact portion between the valve body and the seat surface.
A flow path opening / closing valve characterized by that. The flow path opening / closing valve according to claim 1,
Projecting toward one of the sheet facing portion and the movable sheet toward the movable sheet side or the sheet facing portion side at a position inside the first annular side projection or the second annular side projection. An annular wall adjacent to the other is provided,
A flow path opening / closing valve characterized by that. In the flow path on-off valve according to claim 1 or 2,
The outer periphery of the movable seat, annular outer peripheral projection together when projecting outwardly proximate the inner circumferential surface of the valve chamber is provided,
A flow path opening / closing valve characterized by that. In claim 2 Symbol placement of flow channel opening and closing valve,
An inner annular space is formed between the first annular side protrusion or the second annular side protrusion and the annular wall.
A flow path opening / closing valve characterized by that. In claim 3 Symbol placement of flow channel opening and closing valve,
An outer annular space is formed between the annular outer peripheral projection and the sheet facing portion and outside the first annular side projection,
A flow path opening / closing valve characterized by that.

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