JP2015124813A - Valve assembly - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a valve assembly capable of reducing the number of components and the manufacturing costs.SOLUTION: A valve assembly includes: a housing 2 having a gas passage 200 and assembled to a mating member 9; and a cap member 4 integrally including a valve seat part 41 disposed at an upstream end or a downstream end of the gas passage 200 and on which the valve body 30 is seated, the valve seat part 41 from which the valve body 30 is separated, and a seal member 46 which seals a gap between the mating member 9 and the housing 2. The cap member 4 integrally includes the valve seat part 41 and the seal part 46 which are separately provided in a conventional valve assembly.

Description

  The present invention relates to a valve assembly used for adjusting the flow rate of exhaust gas flowing through, for example, an EGR (Exhaust Gas Recirculation) passage.

  Patent Document 1 discloses a valve assembly. The valve assembly is attached to the valve mounting hole of the engine block. The valve assembly includes a seal member, a valve seat, a valve, and a housing. The seal member is disposed at the exhaust gas inlet of the housing. The seal member is in pressure contact with the step portion of the valve mounting hole. The valve seat is disposed on the inner peripheral surface of the housing. The valve can be seated and separated from the valve seat.

International Publication No. WO99 / 57428 Pamphlet

  As described above, according to the conventional valve assembly, the seal member and the valve seat are arranged independently of each other. For this reason, the conventional valve assembly has many parts. Further, the conventional valve assembly has a high manufacturing cost. Therefore, an object of the present invention is to provide a valve assembly that can reduce the number of parts and the manufacturing cost.

  (1) In order to solve the above problems, a valve assembly of the present invention has a gas passage, a housing assembled to a counterpart member, and is disposed at an upstream end or a downstream end of the gas passage, and a valve body is seated. And a cap member integrally including a valve seat portion that separates and a seal portion that seals a gap between the counterpart member and the housing. Here, “integrally” means that the valve seat portion and the seal portion are arranged on a common member.

  The cap member of the valve assembly of the present invention is integrally provided with a valve seat portion and a seal portion which have been conventionally separated. For this reason, according to the valve assembly of the present invention, the number of parts can be reduced. Further, according to the valve assembly of the present invention, the manufacturing cost can be reduced.

  By the way, from the viewpoint of reducing the number of parts and manufacturing cost, it is conceivable to arrange the valve seat portion in the housing instead of the cap member. However, the housing has a volume that occupies most of the valve assembly. In order to reduce the weight of the valve assembly, the housing is often made of a lightweight material (eg, aluminum, aluminum alloy, etc.). In other words, the housing is often made of a soft material. On the other hand, the valve body repeatedly sits (collises) on the valve seat portion. For this reason, when the valve seat portion is disposed in the housing, the valve seat portion is easily worn.

  In this regard, according to the present configuration, the valve seat portion is disposed on the cap member. For this reason, by making the hardness of the material forming the cap member higher than the hardness of the material forming the housing, wear of the valve seat portion accompanying the seating of the valve body can be suppressed. In addition, by adopting a lightweight material as a material for forming the housing, it is possible to reduce the weight of the housing, and thus the valve assembly.

  (2) In the configuration of (1), the cap member has a fixed portion fixed to the housing, and the valve seat portion and the seal portion are arranged on both sides of the fixed portion, The valve seat portion is preferably not in contact with the housing.

  The sealing part of the cap member seals the gap between the counterpart member and the housing by being pressed against the counterpart member. However, when the seal portion is in pressure contact with the mating member, the seal portion, the vicinity of the seal portion, and the like are elastically deformed. For this reason, there exists a possibility that a valve seat part may also be elastically deformed by the influence of the said elastic deformation.

  In this regard, according to the present configuration, the fixed portion is interposed between the seal portion and the valve seat portion. The fixed part is fixed to the housing. Even if the seal portion or the vicinity of the seal portion is elastically deformed, the fixed portion is hardly elastically deformed. For this reason, the valve seat portion is not easily affected by elastic deformation of the seal portion and the vicinity of the seal portion. Therefore, according to this configuration, it is possible to improve the shut-off performance of the gas passage in the valve closed state (the state where the valve element is seated on the valve seat).

  Moreover, according to this structure, the clearance gap is divided between the valve seat part and the housing. That is, the valve seat part is floating from the housing. For this reason, the valve seat part can buffer the impact accompanying the seating of the valve body by elastically deforming itself. Therefore, the wear of the valve seat portion accompanying the seating of the valve body can be suppressed.

  Moreover, according to this structure, the valve seat part has floated from the housing. For this reason, the shape of the valve seat portion is not easily affected by the shape of the housing. Therefore, in the valve closed state, the shape of the valve seat portion can be easily deformed following the shape of the valve body. Therefore, the shut-off property of the gas passage in the valve closed state can be improved.

  (3) In the configuration of the above (1) or (2), it is preferable that the cap member has a spring portion disposed between the valve seat portion and the seal portion. According to this structure, the pressure-contact force of the seal part with respect to the other party member can be ensured by the spring part.

  (4) In any one of the constitutions (1) to (3), the cap member is preferably formed by pressing a plate material. According to this configuration, an integral cap member having both a valve seat portion and a seal portion can be easily produced.

  According to the present invention, it is possible to provide a valve assembly capable of reducing the number of parts and the manufacturing cost.

It is an up-down direction sectional view in the valve-closing state of the valve assembly of a first embodiment. It is an up-down direction sectional view in the valve opening state of the valve assembly. It is an enlarged view in the circle III of FIG. It is an up-down direction sectional view in the valve-closing state of the valve assembly of a second embodiment. It is an enlarged view in the circle V of FIG.

  Hereinafter, an embodiment in which the valve assembly of the present invention is embodied as a valve assembly for EGR will be described.

<First embodiment>
[Configuration of valve assembly]
First, the configuration of the valve assembly of this embodiment will be described. FIG. 1 is a vertical sectional view of the valve assembly of the present embodiment in a closed state. FIG. 2 is a vertical sectional view of the valve assembly in the valve open state. FIG. 3 shows an enlarged view in a circle III in FIG. As shown in FIGS. 1 to 3, the valve assembly 1 of this embodiment is assembled to an inlet manifold 9. The inlet manifold 9 is included in the concept of the “mating member” of the present invention. The valve assembly 1 according to the present embodiment includes a housing 2, a poppet valve 3, a cap member 4, a seal ring 50, an axial bearing 51, a coil spring 52, and a solenoid 53.

(Inlet manifold 9, housing 2, seal ring 50, axial bearing 51, solenoid 53)
An EGR passage 90 and a recess 91 are formed in the inlet manifold 9. The EGR passage 90 extends in an L shape. The exhaust gas flows through the EGR passage 90 from the lower side (upstream side) toward the right side (downstream side). The recess 91 is recessed on the upper surface of the inlet manifold 9. The recess 91 communicates with the L-shaped corner of the EGR passage 90. The inner diameter of the recess 91 is larger than the inner diameter of the EGR passage 90. For this reason, an annular step portion 910 is formed on the bottom surface of the recess 91.

  The housing 2 is made of an aluminum alloy, and is fixed to the upper surface of the inlet manifold 9 by bolts 99. The housing 2 includes a housing main body 20 and a flange portion 21.

  The housing body 20 is inserted into the recess 91. The housing body 20 is formed with an EGR passage 200, a recess 201, and a valve shaft insertion hole 202. The EGR passage 200 is included in the concept of the “gas passage” of the present invention. The EGR passage 200 is disposed at the L-shaped corner of the EGR passage 90. The EGR passage 200 extends in an L shape. The exhaust gas flows through the EGR passage 200 from the lower side (upstream side) to the right side (downstream side). An inflow port 200 a is arranged at the lower end (upstream end) of the EGR passage 200. The recess 201 is recessed in the upper surface of the housing body 20. A spring seat 201 a is disposed on the bottom surface of the recess 201. The valve shaft insertion hole 202 communicates the EGR passage 200 and the recess 201 in the vertical direction.

  The flange portion 21 extends in the horizontal direction (radial direction) from the upper end of the housing body 20. The flange portion 21 is in contact with the upper surface of the inlet manifold 9. A gap C <b> 1 is defined between the lower surface of the housing body 20 and the stepped portion 910 in a state where the flange portion 21 is in contact with the upper surface of the inlet manifold 9.

  The seal ring 50 is disposed between the lower surface of the flange portion 21 and the upper surface of the inlet manifold 9. The seal ring 50 is elastically deformed. The axial bearing 51 is disposed on the inner peripheral surface of the valve shaft insertion hole 202. The solenoid 53 covers the recess 201 from above. The solenoid 53 includes a plunger (not shown) and a plunger side shaft 530. The plunger and the plunger side shaft 530 are movable in the vertical direction.

(Poppet valve 3, coil spring 52)
The poppet valve 3 includes a valve body 30 and a valve shaft 31. The valve body 30 is made of stainless steel and has a disk shape extending in the horizontal direction (radial direction). The valve shaft 31 includes a shaft main body 310 and a flange portion 311. The shaft main body 310 is made of stainless steel and has a round bar shape extending in the vertical direction (axial direction). The shaft body 310 protrudes upward from the radial center of the valve body 30. The shaft main body 310 is inserted inside the axial bearing 51 in the radial direction. The upper end of the shaft main body 310 is in contact with the plunger side shaft 530. The flange portion 311 has a cup shape opening upward. The flange portion 311 is disposed at the upper end of the shaft main body 310. A spring seat 311 a is disposed on the outer peripheral edge of the flange portion 311.

  The coil spring 52 is disposed between the spring seat 311a and the spring seat 201a. The coil spring 52 urges the poppet valve 3 upward with respect to the housing 2.

(Cap member 4)
The cap member 4 is disposed on the lower surface of the housing body 20. The cap member 4 is made of stainless steel, and has a tapered annular shape whose diameter decreases from the lower side toward the upper side as a whole. The cap member 4 is produced by press-molding a stainless steel plate material.

  The cap member 4 includes a fixed portion 40, a valve seat portion 41, a radially extending portion 42, a chamfered portion 43, an axially extending portion 44, and a spring portion 45 from the upper side to the lower side. And the seal | sticker part 46 is arrange | positioned integrally.

  The fixing part 40 has a short cylindrical shape extending in the vertical direction (axial direction). The fixed portion 40 is press-fitted into the inflow port 200 a of the EGR passage 200. The cap member 4 is fixed to the housing 2 by the press fitting. The valve seat portion 41 has a tapered annular shape that decreases in diameter from the lower side toward the upper side. The valve seat 41 covers the mouth edge of the inflow port 200a. The valve body 30 can be seated and separated with respect to the valve seat portion 41. The radially extending portion 42 has an annular shape extending in the horizontal direction (radial direction). The radially extending portion 42 is in contact with the lower surface of the housing body 20. The chamfered portion 43 connects the radially extending portion 42 and an axially extending portion 44 described later while being curved. The axially extending portion 44 has a cylindrical shape extending in the vertical direction. The axially extending portion 44 protrudes below the housing body 20. The spring portion 45 connects the axially extending portion 44 and a seal portion 46 described later while being curved. The seal portion 46 has a tapered annular shape that decreases in diameter from the lower side toward the upper side. The seal portion 46 is in pressure contact with the step portion 910. The seal portion 46 seals the gap C <b> 1 between the lower surface of the housing body 20 and the step portion 910. That is, the seal portion 46 prevents the exhaust gas from leaking through the gap between the housing 2 and the recess 91 in the closed state shown in FIG.

  A dotted line in FIG. 3 shows the state of the seal portion 46 (no load state) before the housing 2 is assembled to the inlet manifold 9. The vertical distance L1 from the radially extending portion 42 to the seal portion 46 in the no-load state is larger than the gap C1. For this reason, by assembling the housing 2 to the inlet manifold 9, the spring portion 45 and the seal portion 46 are elastically deformed by the difference between the vertical distance L1 and the gap C1. That is, the diameter of the seal portion 46 is increased. Therefore, after the housing 2 is assembled to the inlet manifold 9, the urging force in the reduced diameter direction is accumulated in the seal portion 46. The seal portion 46 is in pressure contact with the step portion 910 by the urging force.

[Motion of valve assembly]
Next, the movement of the valve assembly of this embodiment will be briefly described. When the valve closing state shown in FIG. 1 is switched to the valve opening state shown in FIG. 2, the solenoid 53 is driven to lower the valve shaft 31 against the urging force of the coil spring 52. The valve body 30 is separated from the valve seat portion 41. On the other hand, when switching from the open state shown in FIG. 2 to the closed state shown in FIG. 1, the solenoid 53 is stopped and the valve shaft 31 is raised by the urging force of the coil spring 52. The valve body 30 is seated on the valve seat portion 41.

[Function and effect]
Next, the effects of the valve assembly of this embodiment will be briefly described. As shown in FIG. 3, the cap member 4 of the valve assembly 1 of the present embodiment is integrally provided with a valve seat portion 41 and a seal portion 46 that have been conventionally separated. For this reason, according to the valve assembly 1 of this embodiment, the number of parts can be reduced. Moreover, according to the valve assembly 1 of the present embodiment, the manufacturing cost can be reduced.

  Further, according to the valve assembly 1 of the present embodiment, the valve seat portion 41 is less likely to project inward in the radial direction of the EGR passage 200 as compared with a case where the valve seat portion 41 is a separate body. For this reason, it is easy to ensure a large seat diameter (inner diameter of the valve seat portion 41).

  By the way, from the viewpoint of reducing the number of parts and manufacturing cost, it is also conceivable to set the valve seat 41 to the housing 2 instead of the cap member 4. However, the housing 2 is made of a soft (low hardness) aluminum alloy. On the other hand, the valve body 30 is repeatedly seated (collised) on the valve seat portion 41. For this reason, when the valve seat 41 is set in the housing 2, the valve seat 41 is easily worn.

  In this regard, according to the valve assembly 1 of the present embodiment, the valve seat portion 41 is set to the stainless steel cap member 4. Stainless steel is harder than aluminum alloys. For this reason, according to the valve assembly 1 of the present embodiment, wear of the valve seat portion 41 accompanying the seating of the valve body 30 can be suppressed. In addition, since the housing 2 can be made of a lightweight aluminum alloy, the weight of the valve assembly 1 can be reduced.

  As shown in FIG. 3, the cap member 4 includes a spring portion 45. For this reason, the pressing force of the seal portion 46 against the stepped portion 910 can be ensured by the spring portion 45.

  Moreover, the cap member 4 is produced by press-molding a stainless steel plate material. For this reason, the integral cap member 4 having both the valve seat portion 41 and the seal portion 46 can be easily produced.

<Second embodiment>
The difference between the valve assembly of the present embodiment and the valve assembly of the first embodiment is that a fixing portion is disposed between the valve seat portion and the seal portion in the cap member. Further, the valve seat portion is not in contact with the housing. Here, only differences will be described.

  FIG. 4 is a vertical sectional view of the valve assembly according to the present embodiment in a closed state. In addition, about the site | part corresponding to FIG. 1, it shows with the same code | symbol. FIG. 5 shows an enlarged view in the circle V of FIG. In addition, about the site | part corresponding to FIG. 3, it shows with the same code | symbol.

  As shown in FIGS. 4 and 5, the EGR passage 200 of the housing 2 is formed with a large diameter portion 200b, a small diameter portion 200c, and a step portion 200d from the lower side to the upper side. An inlet 200a is disposed at the lower end of the large diameter portion 200b. The small diameter part 200c continues to the upper side of the large diameter part 200b via the step part 200d.

  The cap member 4 has an axially extending portion 44, a valve seat portion 41, a radially extending portion 42, a chamfered portion 43, a fixing portion 40, and a spring portion 45 from the upper side to the lower side. And the seal | sticker part 46 is arrange | positioned integrally.

  The axially extending portion 44 has a cylindrical shape extending in the vertical direction (axial direction). The axially extending portion 44 is disposed on the radially inner side of the small diameter portion 200c. The axially extending portion 44 is not in contact with the housing 2. The valve seat portion 41 has a tapered annular shape that decreases in diameter from the lower side toward the upper side. The valve seat 41 is not in contact with the housing 2. The valve body 30 can be seated and separated with respect to the valve seat portion 41. The radially extending portion 42 has an annular shape extending in the horizontal direction (radial direction). The radially extending portion 42 is in contact with the stepped portion 200d. The chamfered portion 43 connects the radially extending portion 42 and a fixing portion 40 described later while being curved. The fixed portion 40 has a short-axis cylindrical shape extending in the vertical direction. The fixed part 40 is press-fitted into the large diameter part 200b. The cap member 4 is fixed to the housing 2 by the press fitting. The spring portion 45 connects the fixing portion 40 and a seal portion 46 described later while being curved. The seal portion 46 seals the gap C <b> 1 between the lower surface of the housing body 20 and the step portion 910. That is, the seal portion 46 prevents the exhaust gas from leaking through the gap between the housing 2 and the recess 91 in the closed state shown in FIG.

  A dotted line in FIG. 5 shows the state of the seal portion 46 (no load state) before the housing 2 is assembled to the inlet manifold 9. The vertical distance L1 from the fixed portion 40 (only the portion protruding downward from the inlet 200a) to the seal portion 46 in the no-load state is larger than the gap C1. For this reason, by assembling the housing 2 to the inlet manifold 9, the spring portion 45 and the seal portion 46 are elastically deformed by the difference between the vertical distance L1 and the gap C1. That is, the diameter of the seal portion 46 is increased. Therefore, after the housing 2 is assembled to the inlet manifold 9, the urging force in the reduced diameter direction is accumulated in the seal portion 46. The seal portion 46 is in pressure contact with the step portion 910 by the urging force.

  The valve assembly according to the present embodiment and the valve assembly according to the first embodiment have the same operational effects with respect to the parts having the same configuration. Moreover, according to the valve assembly 1 of the present embodiment, the gap C <b> 1 is sealed by the seal portion 46 being pressed against the step portion 910. However, when the seal portion 46 is in pressure contact with the stepped portion 910, the seal portion 46, the spring portion 45, and the like are elastically deformed. For this reason, there exists a possibility that the valve seat part 41 may also be elastically deformed by the influence of the said elastic deformation.

  In this regard, according to the valve assembly 1 of the present embodiment, the fixing portion 40 is interposed between the seal portion 46 and the valve seat portion 41. The fixed part 40 is press-fitted into the large diameter part 200b. That is, the fixed portion 40 is fixed to the housing 2. Even if the seal portion 46, the spring portion 45, and the like are elastically deformed, the fixing portion 40 is hardly elastically deformed. For this reason, the valve seat 41 is not easily affected by the elastic deformation of the seal portion 46 and the spring portion 45. Therefore, according to the valve assembly 1 of the present embodiment, it is possible to improve the deadline of the EGR passage 200 when the valve is closed.

  Further, according to the valve assembly 1 of the present embodiment, a gap is defined between the valve seat portion 41 and the inner peripheral surface of the EGR passage 200. That is, the valve seat 41 is floating from the inner peripheral surface of the EGR passage 200. For this reason, the valve seat part 41 can buffer the impact accompanying the seating of the valve body 30 by elastically deforming itself. Therefore, wear of the valve seat portion 41 accompanying the seating of the valve body 30 can be suppressed.

  Further, according to the valve assembly 1 of the present embodiment, the valve seat portion 41 floats from the inner peripheral surface of the EGR passage 200. For this reason, the shape of the valve seat portion 41 is not easily affected by the inner peripheral surface of the EGR passage 200. In addition, the valve seat portion 41 is made of a thin plate material having a wall thickness of 1 mm or less (for example, 0.6 mm). Therefore, as emphasized in FIG. 5, even when the shape accuracy of the valve body 30 is low, the shape of the lower surface of the valve seat portion 41 follows the shape of the upper surface of the valve body 30 in the closed state. Can be deformed. Therefore, the deadline of the EGR passage 200 in the valve closed state can be improved.

<Others>
The embodiment of the valve assembly of the present invention has been described above. However, the embodiment is not particularly limited to the above embodiment. Various modifications and improvements that can be made by those skilled in the art are also possible.

  In the above embodiment, the valve assembly 1 is used for the EGR valve. However, the valve assembly 1 may be used as various valves such as an intake-side turbo bypass valve, a throttle valve, an exhaust brake valve, and an exhaust throttle valve.

  In the above embodiment, as shown in FIGS. 3 and 5, the fixing portion 40 is fixed to the housing 2 by press-fitting the fixing portion 40 into the EGR passage 200. However, the fixing portion 40 may be fixed to the housing 2 by means such as adhesion, engagement, screw fastening, and caulking. Moreover, the material of the housing 2 and the cap member 4 is not particularly limited. For example, it may be made of cast iron or resin.

  The structure of the spring portion 45 shown in FIGS. 3 and 5 is not particularly limited. What is necessary is just to be able to press-contact the step part 910, elastically deforming the seal part 46. For example, as the spring portion 45, a thin portion having a thickness smaller than that of the seal portion 46 may be disposed.

1: Valve assembly.
2: housing, 20: housing body, 200: EGR passage (gas passage), 200a: inlet, 200b: large diameter portion, 200c: small diameter portion, 200d: stepped portion, 201: recessed portion, 201a: spring seat, 202: Valve shaft insertion hole, 21: flange portion.
3: Poppet valve, 30: Valve body, 31: Valve shaft, 310: Shaft body, 311: Flange, 311a: Spring seat.
4: cap member, 40: fixing part, 41: valve seat part, 42: radially extending part, 43: chamfered part, 44: axially extending part, 45: spring part, 46: seal part.
50: Seal ring, 51: Axial bearing, 52: Coil spring, 53: Solenoid, 530: Plunger side shaft.
9: Inlet manifold (mating member), 90: EGR passage, 91: recessed portion, 910: stepped portion, 99: bolt.

Claims (4)

A housing having a gas passage and assembled to the mating member;
A valve seat portion that is disposed at an upstream end or a downstream end of the gas passage and on which a valve body is seated and separated and a seal portion that seals a gap between the counterpart member and the housing are integrally formed. A cap member having,
A valve assembly comprising: The cap member has a fixing portion fixed to the housing,
The valve seat part and the seal part are arranged on both sides with the fixed part interposed therebetween,
The valve assembly according to claim 1, wherein the valve seat portion is not in contact with the housing.   The valve assembly according to claim 1, wherein the cap member has a spring portion disposed between the valve seat portion and the seal portion.   The valve assembly according to any one of claims 1 to 3, wherein the cap member is formed by press-molding a plate material.

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