Double eccentric valve

Abstract

A valve seat (13) provided in a flow path of this double eccentric valve includes a valve seat base part (21) made of a rigid material, and a seal member (22) made of an elastic material is provided inside the valve seat base part (21). A connection structure (51) for connecting the seal member (22) and the valve seat base part (21) is provided between the valve seat base part (21) and the seal member (22). The connection structure (51) includes a connection hole (52) provided in the valve seat base part (21), and a connection part (53) provided in the seal member (22) and connected to the connection hole (52). The connection hole (52) includes a first hole part (52a) extending in a circumferential direction (CD) of the valve seat base part (21), and a second hole part (52b) intersecting the first hole part (52a) and extending in an axial direction (AD) of the valve seat base part (21). The connection part (53) is configured to penetrate or engage with the first hole part (52a) and the second hole part (52b) while closing the first hole part (52a) and the second hole part (52b).

Description

Double eccentric valve

[0001] The technology disclosed in this specification relates to, for example, a double eccentric valve used in the flow path of a fuel cell system.

[0002] Conventionally, as this type of technology, for example, the technology "double eccentric valve" described in Patent Document 1 below is known. This double eccentric valve includes a housing including a flow path, a valve seat provided in the flow path, a valve body provided corresponding to the valve seat, a sealing member provided on the valve seat and interposed between the valve body and the valve seat when the valve body seats on the valve seat to seal between the valve body and the valve seat, and a rotating shaft for rotating the valve body. The valve seat has an annular metal valve seat base, and an annular rubber sealing member is provided on the inner peripheral side of the valve seat base. The outer peripheral side of the sealing member is joined along the multi-step outer shape on the inner peripheral side of the valve seat base.

[0003] Japanese Unexamined Patent Application Publication No. 2022-52262

[0004] By the way, in the double eccentric valve described in Patent Document 1, since only the outer peripheral side of the sealing member is joined along the multi-step outer shape on the inner peripheral side of the valve seat base, there is a concern that when a force of the valve body or fluid acts on the sealing member, the sealing member may peel off from the valve seat base and fall off. To prevent the peeling and falling off of the sealing member, it is conceivable to provide a connecting portion with the sealing member in the axial direction of the valve seat base. However, if a connecting portion is provided in the axial direction of the valve seat base, the valve hole of the valve seat has to be enlarged, and there is a possibility that the size of the valve seat will increase.

[0005] This disclosed technology has been made in view of the above circumstances, and its purpose is to prevent the sealing member provided on the valve seat of the double eccentric valve from peeling off from the valve seat base and falling off without increasing the size of the valve seat.

[0006] (1) In order to achieve the above objective, one aspect of the present disclosure includes a housing including a fluid passage, a valve seat provided in the passage and having a valve hole, a valve body provided corresponding to the valve seat and having a sealing surface formed on its outer circumference, the valve seat including a sealing member made of an elastic material that contacts the sealing surface of the valve body to seal the space between the valve body and the valve seat when the valve body is seated on the valve seat in a fully closed position, and a rotating shaft for rotating the valve body, the axis of the rotating shaft which is the rotation center of the valve body being positioned away from the sealing surface of the valve body in the direction in which the axis of the valve body extends, and away from the axis of the valve body in the radial direction of the valve body. In a double eccentric valve comprising the above, the valve seat includes a valve seat base made of a rigid material, a sealing member is provided inside the valve seat base, and a connecting structure is provided between the valve seat base and the sealing member for connecting the sealing member and the valve seat base, the connecting structure includes a connecting hole provided in the valve seat base and a connecting portion provided in the sealing member and connected to the connecting hole, the connecting hole includes a first hole extending in the circumferential direction of the valve seat base and a second hole intersecting the first hole and extending in the axial direction of the valve seat base, and the connecting portion is configured to penetrate or engage with the first hole and the second hole while closing them.

[0007] According to this embodiment, a sealing member provided inside the valve seat base is connected by a connecting structure provided between the two. The connecting structure includes a connecting hole provided in the valve seat base and a connecting portion provided in the sealing member and connected to the connecting hole. Here, the connecting hole includes a first hole extending in the circumferential direction of the valve seat base and a second hole intersecting the first hole and extending in the axial direction of the valve seat base. The connecting portion penetrates or engages with the first hole and the second hole, while closing them. Therefore, the connecting hole is formed within the outer shape of the valve seat base, and the connecting portion of the sealing member is connected to the connecting hole by penetrating or engaging with it. Furthermore, since the connecting hole includes a first hole extending in the circumferential direction of the valve seat base and a second hole extending in the axial direction of the valve seat base, the connecting hole and the connecting portion are positioned in both the circumferential and axial directions of the valve seat base.

[0008] The technology described in (2) is intended to be used in the manner of (1) for adjusting the air flow rate in a fuel cell system.

[0009] According to this embodiment, a double eccentric valve used for adjusting the air flow rate in a fuel cell system can be made to perform the same function as the technology described in (1) above.

[0010] According to the technology described in (1), the sealing member provided on the valve seat of a double eccentric valve can be fixed in the circumferential and axial directions of the base of the valve seat without increasing the size of the valve seat, and it is possible to prevent the sealing member from peeling off from the base of the valve seat and falling off.

[0011] According to the technology described in (2), the same effect as the technology described in (1) can be obtained as a double eccentric valve used for adjusting the air flow rate in a fuel cell system.

[0012] A schematic diagram showing a fuel cell system in which a double eccentric valve is used according to one embodiment. A perspective view showing a double eccentric valve according to one embodiment. A perspective view showing a part of the valve section in the fully closed state of a double eccentric valve according to one embodiment. A perspective view showing a part of the valve section in the fully open state of a double eccentric valve according to one embodiment. A side view showing the valve seat, valve body, and rotating shaft in the fully closed state of a double eccentric valve according to one embodiment. A cross-sectional view of the double eccentric valve along line A-A in Figure 5 according to one embodiment. A cross-sectional view showing the area around the valve seat and press-fit section according to one embodiment. A perspective view showing the valve seat according to one embodiment. A perspective view showing only the valve seat base that constitutes the valve seat according to one embodiment. A perspective view cut along line B-B in Figure 8 showing a part of the valve seat according to one embodiment. A perspective view showing one of the connecting holes in Figure 9 according to one embodiment.

[0013] Hereinafter, one embodiment of the double eccentric valve, specifically a double eccentric valve used in the flow path of a fuel cell system, will be described in detail with reference to the drawings.

[0014] [About the Fuel Cell System] A fuel cell system using a double eccentric valve will be described. Figure 1 shows a schematic configuration of the fuel cell system 101 of this embodiment. As shown in Figure 1, the fuel cell system 101 has a fuel cell (hereinafter referred to as "FC stack") 111, a hydrogen system 112, and an air system 113.

[0015] The FC stack 111 generates electricity by receiving a supply of fuel gas (hydrogen gas) and an oxidizer gas (air). Specifically, the FC stack 111 generates electricity by receiving hydrogen gas from the hydrogen system 112 and air from the air system 113. The electricity generated by the FC stack 111 is supplied to a drive motor (not shown) via, for example, an inverter (not shown).

[0016] The hydrogen system 112 includes a hydrogen supply passage 121 and a hydrogen discharge passage 122. The hydrogen supply passage 121 is a passage for supplying hydrogen gas from a hydrogen tank (not shown) to the FC stack 111. The hydrogen discharge passage 122 is a passage for discharging hydrogen gas (hydrogen off-gas) discharged from the FC stack 111.

[0017] The air system 113 includes an air supply passage 131, an air discharge passage 132, and a bypass passage 133. The air supply passage 131 is a passage for supplying air to the FC stack 111 from outside the fuel cell system 101. The air discharge passage 132 is a passage for discharging air (air-off gas) discharged from the FC stack 111. The bypass passage 133 is a passage for allowing air to flow from the air supply passage 131 to the air discharge passage 132 without passing through the FC stack 111.

[0018] The air system 113 includes an inlet sealing valve 141 in the air supply passage 131. The inlet sealing valve 141 is a valve that opens and closes the air supply passage 131 and switches between supplying and shutting off air to the FC stack 111. In this embodiment, a double eccentric valve 1, which will be described later, is used as the inlet sealing valve 141.

[0019] Furthermore, the air system 113 includes an outlet sealing valve 142 in the air discharge passage 132. The outlet sealing valve 142 is a valve that opens and closes the air discharge passage 132 and switches between discharging and shutting off the air-off gas from the FC stack 111. In this embodiment, a double eccentric valve 1, which will be described later, is used as the outlet sealing valve 142.

[0020] Furthermore, the air system 113 includes a bypass valve 143 in the bypass passage 133. The bypass valve 143 is a valve that controls the flow rate of air in the bypass passage 133. Note that a double eccentric valve 1, which will be described later, may be used as the bypass valve 143.

[0021] In the fuel cell system 101 described above, hydrogen gas supplied to the FC stack 111 from the hydrogen supply passage 121 is used for power generation in the FC stack 111. Hydrogen gas not used for power generation is discharged to the outside as hydrogen off-gas from the FC stack 111 via the hydrogen discharge passage 122. In addition, air supplied to the FC stack 111 from the air supply passage 131 is used for power generation in the FC stack 111. Air not used for power generation is discharged to the outside as air off-gas from the FC stack 111 via the air discharge passage 132.

[0022] [Regarding the double eccentric valve] Next, we will describe the double eccentric valve used as the inlet sealing valve 141, outlet sealing valve 142, and bypass valve 143 in the fuel cell system 101 described above.

[0023] Figure 2 shows a perspective view of the double eccentric valve 1 of this embodiment. As shown in Figure 2, the double eccentric valve 1 comprises a valve section 2, a motor section 3 containing a motor, and a reduction gear section 4 containing a plurality of gears. The valve section 2 includes a pipe section 12 having a flow path 11. A valve seat 13, a valve body 14, and a rotating shaft 15 are arranged in the flow path 11. The rotational force of the motor is transmitted to the rotating shaft 15 via a plurality of gears. In this embodiment, the pipe section 12 constitutes part of the housing 6. The motor of the motor section 3 and the plurality of gears of the reduction gear section 4 are covered by this housing 6. The housing 6 is made of a metal such as aluminum.

[0024] Figure 3 shows a perspective view of the double eccentric valve 1 with the valve section 2 in the fully closed state partially cut away. Figure 4 shows a perspective view of the double eccentric valve 1 with the valve section 2 in the fully open state partially cut away. As shown in Figures 3 and 4, a stepped press-fit section 10 is formed in the pipe section 12. In this embodiment, the valve seat 13 is assembled by press-fitting it into this press-fit section 10.

[0025] The valve seat 13 is annular in shape and has a circular or substantially circular valve bore 16 in the center. An annular seat surface 17 is formed on the edge of the valve bore 16. In this embodiment, the valve seat 13 includes a sealing member 22 for sealing the space between the valve seat 13 and the valve body 14. The seat surface 17 is formed on the sealing member 22. Details of the valve seat 13 will be described later.

[0026] The valve body 14 is disc-shaped, and an annular sealing surface 18 corresponding to the seat surface 17 is formed on its outer circumference. The valve body 14 is fixed to the rotating shaft 15 and rotates integrally with the rotating shaft 15 to contact and separate from the valve seat 13.

[0027] Figure 5 shows a side view of the double eccentric valve 1, including the valve seat 13, valve body 14, and rotating shaft 15 in the fully closed state. Figure 6 shows the double eccentric valve 1 in a cross-sectional view along line A-A in Figure 5. As shown in Figure 6, the axis L1 of the rotating shaft 15 extends parallel to the radial direction of the valve body 14 and valve bore 16, and is positioned eccentrically from the center P1 of the valve bore 16 in the radial direction of the valve bore 16. In conjunction with this, the sealing surface 18 of the valve body 14 is positioned eccentrically in the direction in which the axis L2 of the valve body 14 extends from the axis L1 of the rotating shaft 15.

[0028] As shown in Figures 5 and 6, the valve body 14 includes a fixing portion 14b that protrudes from its upper plate surface 14a and is fixed to the rotating shaft 15. The rotating shaft 15 has a pin 15a that protrudes from the tip of the rotating shaft 15 at a position offset radially from its axis L1. The fixing portion 14b is fixed to the rotating shaft 15 via the pin 15a. Also, as shown in Figure 6, the fixing portion 14b is positioned on the axis L2 of the valve body 14, and the valve body 14 including the fixing portion 14b has a symmetrical shape with respect to the axis L2 of the valve body 14.

[0029] In this configuration, the double eccentric valve 1 is displaced from a fully closed state (see Figure 3) where the sealing surface 18 of the valve body 14 abuts against the seat surface 17 of the valve seat 13, to a fully open state (see Figure 4) where the sealing surface 18 of the valve body 14 is separated from the seat surface 17 of the valve seat 13, by rotating the valve body 14 around the axis L1 of the rotation shaft 15.

[0030] [Regarding the valve seat] Figure 7 shows a cross-sectional view (a cross-sectional view of the valve seat 13 cut along its axial direction) of the valve seat 13 and the area around the press-fit portion 10. In Figure 7, for the sake of explanation, the valve body 14 and the rotating shaft 15 are omitted from the illustration.

[0031] As shown in Figure 7, the valve seat 13 includes a valve seat base 21 made of a rigid material and a sealing member 22 made of an elastic material, which is provided inside the valve seat base 21. Both the valve seat base 21 and the sealing member 22 are formed in an annular shape. The valve seat base 21 is made of a metal plate such as stainless steel and has a channel-shaped radial cross-section. That is, the valve seat base 21 includes an inner circumferential wall 21b, an outer circumferential wall 21c, and a bottom wall 21d connecting both circumferential walls 21b and 21c. The sealing member 22 is made of rubber and is formed in a substantially cylindrical shape. The sealing member 22 is integrally attached to the valve seat base 21 by means of baking or the like. A connecting structure 51 (see Figures 8 and 10) is provided between the valve seat base 21 and the sealing member 22 to connect them. Details of the connecting structure 51 will be described later.

[0032] As shown in Figure 7, the press-fit portion 10 is formed in a stepped shape on the lower inner wall of the flow path 11. The press-fit portion 10 comprises a first contact surface 31, a second contact surface 32, and a press-fit surface 33. The first contact surface 31 and the second contact surface 32 are formed so as to intersect (perpendicular to) the press-fit direction DP of the valve seat 13 into the press-fit portion 10. The first contact surface 31 and the second contact surface 32 are formed adjacent to each other in the radial direction, separated by a step in the press-fit direction DP. The first contact surface 31 and the second contact surface 32 form an annular shape in plan view. The first contact surface 31 is the surface to which one end (lower side) of the valve seat base 21 in the axial direction (up and down direction in Figure 7) abuts. The second contact surface 32 is the surface to which one end (lower side) of the seal member 22 in the axial direction (up and down direction in Figure 7) abuts. The second contact surface 32 is positioned at a location offset from the first contact surface 31 in the press-fit direction DP (downward in Figure 7).

[0033] The valve seat base 21 has a flat contact portion 21a at its end in the press-fitting direction DP that contacts the first contact surface 31. The sealing member 22 has a protrusion 22a at its end in the press-fitting direction DP that contacts the second contact surface 32. This protrusion 22a is formed continuously in an annular shape in the circumferential direction of the sealing member 22.

[0034] [Regarding the connection structure between the valve seat base and the sealing member] Figure 8 shows a perspective view of the valve seat 13. Figure 9 shows a perspective view of only the valve seat base 21 that constitutes the valve seat 13. Figure 10 shows a perspective view of a part of the valve seat 13 cut along the line B-B in Figure 8. As shown in Figures 8 to 8 and Figure 10, a connecting structure 51 is provided between the valve seat base 21 and the sealing member 22 to connect the sealing member 22 and the valve seat base 21. The connecting structure 51 includes a connecting hole 52 provided in the inner circumferential wall 21b of the valve seat base 21 and a connecting portion 53 provided in the sealing member 22 and connected to the connecting hole 52.

[0035] Figure 11 shows a perspective view of one of the connecting holes 52 in Figure 9. As shown in Figure 11, the connecting hole 52 includes a first hole portion 52a extending in the circumferential direction CD of the valve seat base 21, and a second hole portion 52b intersecting the first hole portion 52a and extending in the axial direction AD of the valve seat base 21. In other words, the connecting hole 52 is T-shaped. In this embodiment, the end of the second hole portion 52b is bent in an L-shape in the radial direction RD of the valve seat base 21.

[0036] As shown in Figure 10, the connecting portion 53 is configured to penetrate or engage with the first hole 52a and the second hole 52b while closing them.

[0037] [Operation and Effects of the Double Eccentric Valve] According to the configuration of the double eccentric valve 1 of this embodiment described above, the sealing member 22 provided on the inner circumference side of the valve seat base 21 is connected by a connecting structure 51 provided between the two 21 and 22. The connecting structure 51 includes a connecting hole 52 provided in the valve seat base 21 and a connecting portion 53 provided in the sealing member 22 and connected to the connecting hole 52. Here, the connecting hole 52 includes a first hole 52a extending in the circumferential direction CD of the valve seat base 21 and a second hole 52b intersecting the first hole 52a and extending in the axial direction AD and radial direction RD of the valve seat base 21. The connecting portion 53 penetrates or engages with the first hole 52a and the second hole 52b while blocking them. Therefore, the connecting hole 52 is formed within the outer shape of the valve seat base 21, and the connecting portion 53 of the sealing member 22 is connected by passing through or engaging with the connecting hole 52. Furthermore, since the connecting hole 52 includes a first hole portion 52a extending in the circumferential direction CD of the valve seat base 21 and a second hole portion 52b extending in the axial direction AD and radial direction RD of the valve seat base 21, the connecting hole 52 and the connecting portion 53 are positioned in the circumferential direction CD, axial direction AD and radial direction RD of the valve seat base 21. For this reason, the sealing member 22 provided on the valve seat 13 of the double eccentric valve 1 can be fixed in the circumferential direction CD, axial direction AD and radial direction RD of the valve seat base 21 without increasing the size of the valve seat 13, and the sealing member 22 can be prevented from peeling off and falling off from the valve seat base 21. Even if the sealing member 22 begins to peel off from the valve seat base 21, the anchoring function of the connecting portion 53 can reduce the extent of the peeling.

[0038] According to the configuration of this embodiment, the connecting hole 52 is formed in a T-shape with a first hole portion 52a and a second hole portion 52b, so the cross-sectional area of ​​the connecting hole 52 can be increased even in the narrow space of the valve seat base portion 21. Furthermore, since the end of the second hole portion 52b is bent in an L-shape radially RD toward the valve seat base portion 21, the cross-sectional area of ​​the second hole portion 52b can also be increased even in the narrow space. This increase in the cross-sectional area of ​​the connecting hole 52 leads to an improvement in the connecting function of the connecting structure 51.

[0039] According to the configuration of this embodiment, the valve seat base 21 is formed of a metal plate such as stainless steel, and has a channel-shaped cross section in the radial direction. Therefore, the weight of the valve seat base 21 can be reduced, and consequently, the weight of the valve seat 13 can be reduced.

[0040] According to the configuration of this embodiment, the double eccentric valve 1 described above is used as the inlet shut-off valve 141, the outlet shut-off valve 142, and the bypass valve 143 for adjusting the air flow rate in the FC stack 111 shown in FIG. 1. Therefore, as the double eccentric valve 1 used in the fuel cell system 101, the same operations and effects as described above can be obtained.

[0041] Note that the disclosed technology is not limited to the above embodiment, and a part of the configuration can be appropriately changed and implemented without departing from the spirit of the disclosed technology.

[0042] (1) In the above embodiment, the double eccentric valve 1 is embodied as the various valves 141 to 143 used in the flow path through which the air of the fuel cell system 101 flows. However, the embodiment of the double eccentric valve is not limited to the fuel cell system.

[0043] (2) In the above embodiment, the connecting hole 52 is composed of a first hole portion 52a extending in the circumferential direction CD of the valve seat base 21 and a second hole portion 52b extending in the axial direction AD and the radial direction RD of the valve seat base 21. However, the portion of the second hole portion 52b extending in the radial direction RD can also be omitted.

[0044] (3) In the above embodiment, the connecting hole 52 is formed in a T shape by the first hole portion 52a and the second hole portion 52b. However, the connecting hole can also be formed in a cross shape by the first hole portion and the second hole portion.

[0045] 1 Double eccentric valve 6 Housing 10 Press-fitting portion 11 Flow path 13 Valve seat 14 Valve body 15 Rotating shaft 16 Valve hole 21 Valve seat base 22 Sealing member 51 Connecting structure 52 Connecting hole 52a First hole portion 52b Second hole portion 53 Connecting portion 101 Fuel cell system 141 Inlet shut-off valve 142 Outlet shut-off valve 143 Bypass valve CD Circumferential direction AD Axial direction DP Press-fitting direction L1 Axis (of the rotating shaft) L2 Axis (of the valve body)

Claims

1. A double eccentric valve comprising: a housing including a fluid passage; a valve seat provided in the fluid passage and having a valve hole; a valve body having a sealing surface formed on its outer circumference and provided corresponding to the valve seat; the valve seat including a sealing member made of an elastic material for sealing the space between the valve body and the valve seat by contacting the sealing surface of the valve body when the valve body is seated on the valve seat in a fully closed position; a rotating shaft for rotating the valve body; the axis of the rotating shaft, which is the rotation center of the valve body, is positioned away from the sealing surface of the valve body in the direction in which the axis of the valve body extends, and is positioned away from the axis of the valve body in the radial direction of the valve body; wherein the valve seat includes a valve seat base made of a rigid material, the sealing member is provided inside the valve seat base, and a connecting structure is provided between the valve seat base and the sealing member for connecting the sealing member and the valve seat base; The connecting structure includes a connecting hole provided in the valve seat base and a connecting portion provided in the sealing member and connected to the connecting hole, wherein the connecting hole includes a first hole extending in the circumferential direction of the valve seat base and a second hole intersecting the first hole and extending in the axial direction of the valve seat base, and the connecting portion is configured to penetrate or engage with the first hole and the second hole while closing them.

2. A double eccentric valve according to claim 1, characterized in that it is used for adjusting the flow rate of air in a fuel cell system.

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