JP2009299770A - Valve device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a valve device capable of smoothly opening and closing a valve element even in a low temperature environment by improving operability. <P>SOLUTION: This valve device has a body for arranging a primary chamber 110a for introducing fluid and a secondary chamber 120a for deriving the fluid, a shaft 140 extended to the primary chamber 110a side from the secondary chamber 120a side and displaced in the axial direction by a driving mechanism, and the valve element 130 for making the primary chamber 110a and the secondary chamber 120a communicative with each other, or disconnecting them according to the displacement of the shaft 140. The valve element 130 is arranged in the primary chamber 110a, and constituted so as to open a valve by being displaced toward a primary chamber 110a wall forming the primary chamber 110a. The valve element 130 is characterized in that at least its top 135 is formed of a curved projecting elastic member capable of elastically abutting on the wall. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a valve device.

  In recent years, a polymer electrolyte fuel cell (Polymer Electrolyte Fuel Cell) that generates electricity by supplying hydrogen (fuel gas, reactive gas) to the anode and oxygen-containing air (oxidant gas, reactive gas) to the cathode, respectively. The development of fuel cells such as PEFC is active. In a system using such a fuel cell, a valve device for permitting or shutting off the flow of a fluid such as air containing hydrogen or oxygen is used (see Patent Document 1).

  By the way, when the fuel cell as described above generates electric power, water vapor (water) is generated at the cathode, and part of the generated water permeates to the anode side through the electrolyte membrane (solid polymer membrane). Further, in order to maintain the wet state of the electrolyte membrane, hydrogen and air toward the fuel cell are humidified by a humidifier equipped with a hollow fiber membrane. Therefore, the fuel cell, the anode off-gas discharged from the anode, and the cathode off-gas discharged from the cathode are humid. Therefore, if the fuel cell is exposed to a low temperature environment (for example, less than 0 ° C.) after the power generation is stopped, the fuel cell or the accessory device may freeze.

  Therefore, when there is a risk of freezing, a technology is known in which a scavenging gas (non-humidified air, nitrogen, etc.) is pushed into the fuel cell and water such as water vapor or condensed water remaining in the fuel cell is pushed out to scavenge the fuel cell. It has been. And the scavenging gas discharged | emitted from the fuel cell with the water | moisture content is discharged | emitted via the scavenging gas discharge valve as a valve apparatus opened at the time of scavenging.

JP 2006-153177 A

  As described above, a valve device such as a scavenging gas discharge valve is used in an environment through which moisture such as water vapor or condensed water passes. For this reason, in a low-temperature environment (for example, less than 0 ° C.), moisture remaining inside the valve device may be frozen, and the operability of the valve body may be impaired by the frozen moisture. It was rare.

  Then, this invention makes it a subject to provide the valve apparatus which can improve an operativity and can open and close a valve body smoothly also in a low temperature environment.

  In order to solve the above problems, a valve device of the present invention includes a body provided with a primary chamber into which a fluid is introduced and a secondary chamber into which the fluid is led out, and from the secondary chamber side to the primary chamber side. A shaft that is extended and displaced in the axial direction by a drive mechanism; and a valve body that communicates or blocks between the primary chamber and the secondary chamber in accordance with the displacement of the shaft, The valve body is arranged so as to open by being displaced toward the wall of the primary chamber that forms the primary chamber, and the valve body has at least a top portion with respect to the wall. It is formed of a curved convex elastic member that can be elastically contacted.

  According to this valve device, at least the top of the valve body is formed of a curved convex elastic member that can elastically contact the upper wall. Even if moisture passes, it can be avoided that they remain on the top of the valve body. Thereby, it is possible to suitably prevent freezing and sticking of the valve body due to moisture retention.

  In addition, since the top portion is formed of a curved convex elastic member that can elastically contact the upper wall, for example, the adhesion to the upper wall is higher than when the top portion is formed flat. It is possible to suitably prevent the valve body from adhering to the upper wall due to the water freezing.

  In addition, since the top portion is formed of a curved convex elastic member that can elastically abut against the upper wall, the impact is mitigated when abutting against the upper wall, and the contact of the valve body is reduced. The contact sound is reduced, and quietness can be realized.

For example, when such a valve device is used as a scavenging gas discharge valve in a fuel cell system, the following advantages can be obtained.
In other words, even when anode off-gas containing water such as water vapor or condensed water passes, it can be avoided that these stay at the top of the valve body, and freezing and sticking of the valve body due to the retention of water is suitable. Can be prevented. Therefore, stable opening and closing of the valve body can be maintained over a long period of time, which contributes to the realization of a fuel cell system having excellent durability and excellent reliability.

The valve body may be configured such that the seating portion is formed of an elastic member integral with the top portion.
According to this valve device, the seat portion and the top portion are formed of an integral elastic member, so that the rigidity is increased and the number of parts can be reduced. Thereby, the part cost and the assembly cost are reduced, and the manufacturing cost can be reduced.

  The valve body is formed by attaching an elastic member to a concentric cylindrical base portion having a hollow portion, and the top side and the seating portion side are integrally provided through the hollow portion. It is good to have a configuration.

  According to this valve device, since the valve body has a concentric cylindrical shape having a hollow portion, the weight can be reduced. In addition, since the top portion side and the seating portion side are provided as an integral elastic member through the hollow portion, the elastic member is arranged in a balanced manner with respect to the valve body, and the operability of the valve body is improved.

  A diaphragm which is provided between the wall of the secondary chamber and the shaft and which is locked to the shaft and bends following the displacement operation of the shaft; and the diaphragm moves to the valve body side. A curved convex skirt portion that protrudes toward the drive mechanism, and is provided on the back surface side of the skirt portion so as to be inserted into a recess on the back surface side of the skirt portion. It has the projection part which controls that it will be in the state where it deformed toward the back side.

According to this valve device, a satisfactory displacement operation of the shaft can be ensured by the deflection of the diaphragm. Moreover, even if the skirt portion of the diaphragm is deformed toward the back side due to the fluid pressure at the time of valve opening or the like by providing the projection portion, the projection portion is in contact with the deformed portion from the back side. Thus, the deformation of the diaphragm can be suppressed. Therefore, the state in which the skirt portion of the diaphragm is raised toward the valve body side can be suitably maintained, and it is not necessary to ensure the rigidity of the diaphragm by forming the diaphragm thickly. That is, the diaphragm can be formed thin.
Therefore, it is possible to obtain a valve device that can secure the flow rate by increasing the stroke length of the shaft and can move the valve body smoothly with good response.

  In addition, the body on the secondary chamber side opens to the surface and a shaft side chamber formed on the side of the end of the shaft, and the shaft side chamber communicates with the outside of the body on the secondary chamber side. A breathable waterproof material that prevents air from entering and exiting while allowing air to enter and exit from the opening of the air passage formed in the surface of the body on the secondary chamber side. It is preferable to have a configuration in which a cap having the above is attached.

  According to this valve device, since the cap having the moisture permeable waterproof material is attached to the opening portion of the air passage that communicates the shaft side chamber with the outside of the body on the secondary chamber side. It is possible to prevent water and the like from entering while allowing the air to enter and exit. Therefore, a stable shaft displacement operation can be ensured, and the operability of the valve body is improved.

  ADVANTAGE OF THE INVENTION According to this invention, the operativity can be improved and the valve apparatus which can open and close a valve body smoothly also in a low temperature environment is obtained.

Hereinafter, embodiments of the present invention will be described with reference to the drawings as appropriate.
In the present embodiment, the valve device applied to the fuel cell system will be described, but the device to which the valve device is applied is not intended to be limited. Hereinafter, a case where the valve device is used in an anode system of a fuel cell system will be described as an example.

First, the configuration of a fuel cell system to which the valve device of the present embodiment is applied will be described, and the valve device will be described in the following description.
≪Configuration of fuel cell system≫
A fuel cell system 1 according to this embodiment shown in FIG. 1 is mounted on a fuel cell vehicle (moving body) (not shown). The fuel cell system 1 includes a fuel cell stack 10, an anode system that supplies and discharges hydrogen (fuel gas and reaction gas) to and from the anode of the fuel cell stack 10, and air that contains oxygen with respect to the cathode of the fuel cell stack 10. A cathode system for supplying and discharging (oxidant gas, reaction gas).

<Anode system>
The anode system includes a hydrogen tank 21 (fuel gas supply means), a normally closed shut-off valve 22, an ejector 23, a normally closed purge valve 24, and a normally closed scavenging gas discharge valve 100. Hydrogen is supplied to the inlet side of the anode flow path 11 of the fuel cell stack 10 through the shutoff valve 22 and the ejector 23. The outlet of the anode channel 11 is connected to the suction port of the ejector 23 via the circulation channel 23a. The anode off-gas returned to the ejector 23 is mixed with hydrogen from the hydrogen tank 21 and then re-supplied to the anode channel 11.

  A purge valve 24 and a scavenging gas discharge valve 100 are connected to the outlet of the anode channel 11. The purge valve 24 is a normally closed electromagnetic valve, and discharges (purifies) impurities (water vapor, nitrogen, etc.) contained in the anode off-gas (hydrogen) circulating through the circulation path 23a when the fuel cell stack 10 generates power. In this case, it is appropriately opened by an ECU (Electronic Control Unit). The anode off gas discharged through the purge valve 24 is diluted by a diluter 33 connected to the downstream side and then discharged to the outside.

The scavenging gas discharge valve 100 is a normally closed electromagnetic valve and is a valve that is opened when the fuel cell stack 10 is scavenged. Below, the example using the valve apparatus of this embodiment is demonstrated with respect to the scavenging gas exhaust valve 100 with which this fuel cell stack 10 is provided downstream.
Specifically, the scavenging gas discharge valve 100 is opened by a command from the ECU in a state where the compressor 31 is operated when scavenging the anode flow path 11 of the fuel cell stack 10. The scavenging gas discharge valve 100 is set to be opened together with a normally closed scavenging gas introduction valve (not shown) provided in a pipe (not shown) that guides the scavenging gas (non-humidified air) from the compressor 31 to the anode system. It has become.

As shown in FIG. 2, the scavenging gas discharge valve 100 forms a primary chamber 110 a and is provided with a primary chamber body 110 (body) provided with an introduction port 111 through which anode off-gas is introduced, and a lower portion of the primary chamber body 110. There is provided a secondary chamber body 120 (body) provided adjacent to form a secondary chamber 120a and provided with a lead-out port 121 through which the anode off-gas is led out. The scavenging gas discharge valve 100 communicates between the primary chamber 110a and the secondary chamber 120a by driving the valve body 130 by a solenoid 150 that constitutes a drive mechanism disposed on the lower side of the secondary chamber body 120. It is configured to switch states. That is, the scavenging gas discharge valve 100 opens during scavenging, and discharges the anode off-gas sent from the anode flow path 11 of the fuel cell stack 10 to the subsequent-stage diluter 33 as shown in FIG. It is designed to function as a valve.
In the present embodiment, the primary chamber body 110 on the side into which the high-pressure anode off gas is introduced is disposed on the upper side, and the secondary chamber body 120 on the side from which the anode off gas is led out is disposed on the lower side. The solenoid 150 for driving the valve body 130 is arranged below the secondary chamber body 120.

  Here, in the scavenging gas discharge valve 100, the anode off-gas sent from the anode flow path 11 (see FIG. 1, the same applies hereinafter) of the fuel cell stack 10 (see FIG. 1, the same applies hereinafter) flows. Since it is a valve, moisture such as water vapor or condensed water passes through the anode off gas. For this reason, in order to prevent freezing and sticking to the upper wall (wall) of the primary chamber body 110 of the valve body 130 due to moisture retention, the top portion 135 of the valve body 130 is elastic with respect to the upper wall of the primary chamber 110a. It is formed of an elastic member having a curved convex shape that can come into contact with each other.

Hereinafter, each part will be described in detail.
As described above, the primary chamber body 110 has the introduction port 111 that can be connected to the pipe from the anode flow path 11 of the fuel cell stack 10, and through this introduction port 111, the high-pressure from the fuel cell stack 10. An anode off gas is introduced into the primary chamber 110a.
The introduction port 111 is provided on the left side of the primary chamber body 110 and has an opening to which a pipe from the anode channel 11 is connected. In the present embodiment, the introduction port 111 is positioned above the derivation port 121. That is, the anode off gas containing moisture flows in a direction from the top to the bottom (gravity direction).

  A valve body 130 is disposed in the primary chamber 110a so as to be displaceable in the vertical direction (valve opening / closing direction). That is, the valve body 130 is configured to open by being displaced toward the upper wall (recess 112) of the primary chamber body 110 forming the primary chamber 110a. The valve is closed by sitting on the provided valve seat 116.

  As shown in FIGS. 3A to 3B, the valve body 130 includes a base portion 131, a buffer member 134 attached to the base portion 131, and a shaft holding member 138 inserted and held in the buffer member 134. I have. Hereinafter, an example in which the base 131, the buffer member 134, and the shaft holding member 138 are separately formed and the valve body 130 is obtained by sequentially assembling them will be described. By using the manufacturing method, the base 131 and the shaft holding member 138 are configured by a single member provided with a molding passage that communicates the upper surface and the lower surface, and the buffer member 134 is formed integrally, as in the prior art. Thus, the valve body 130 may be obtained.

As shown in FIG. 4, the base 131 is a metal member such as an aluminum alloy having a stepped cylindrical shape, and a buffer member 134 is inserted into the hollow portion 131a from below and attached. Yes. The base part 131 includes a body part 132 and a flange part 133 connected to the lower part of the body part 132, and has a substantially hat shape in a side view.
As shown in FIGS. 3 (a) and 3 (b), the outer peripheral edge 132a of the upper end of the body 132 is chamfered, and the top 135 of the buffer member 134, which will be described later, extends from the top edge 135 to the outer periphery 132a of the body 132. As shown in FIG.3 (b), it forms so that it may become a substantially continuous inclined surface. As a result, moisture adheres to the top portion 135 of the buffer member 134 due to the anode off gas flowing through the primary chamber 110a (see FIG. 2). Is suitably transmitted from the top portion 135 to the outer peripheral edge portion 132a and flows down.
Further, the inner peripheral surface 132b of the trunk portion 132 has a cylindrical surface shape, and the buffer portion 134 is mounted on the base portion 131, and the inner peripheral surface 132b has a connecting portion 136 described later on the buffer member 134. The outer peripheral surface 136a is in close contact.

The flange portion 133 protrudes laterally from the lower end of the body portion 132, and a spring 113 described later is interposed between the upper surface 133a and the recess 112 formed in the upper wall of the primary chamber 110a shown in FIG. Has been reduced. As a result, the valve body 130 is urged by the spring 113 toward the valve seat 116 provided below the valve body 130 when not energized, and is seated on the valve seat 116.
Further, as shown in FIG. 3B, the outer peripheral portion of the flange portion 133 extends downward, and the buffer member 134 is described later in a recess formed by the inner peripheral surface 133b and the bottom surface 133c. A part of the side surface 137a of the seating portion 137 and the upper surface 137b are fitted.

As shown in FIGS. 3B and 4, the buffer member 134 includes a top portion 135, a seating portion 137, and a connecting portion 136 that connects the top portion 135 and the seating portion 137. As the buffer member 134, an elastic member such as synthetic rubber having high strength and excellent weather resistance, for example, ethylene-propylene-diene rubber (EPDM) or the like can be used.
The top portion 135 has a substantially hemispherical shape (curved convex shape), and can elastically contact the concave portion 112 (see FIG. 2) on the upper wall when the valve is opened. Moreover, since it is made into a substantially hemispherical shape, the contact area with respect to the contact surface of the recessed part 112 is small compared with the case where the top part 135 is formed flat.
The top portion 135 has a lower outer diameter that is larger than the outer diameter of the connecting portion 136. With the buffer member 134 attached to the base portion 131, the lower end portion 135a of the lower portion is shown in FIG. As shown, it is arranged in a state of covering a part of the upper end portion of the body portion 132 on the base portion 131 side. Accordingly, as described above, a substantially continuous inclined surface is formed from the lower portion of the top portion 135 to the outer peripheral edge portion 132a of the upper end portion of the trunk portion 132.
Further, the top portion 135 has a substantially constant thickness at the top, and the shaft holding member 138 is disposed so as to be in close contact with the bottom surface 135b side.

The seat portion 137 has a circular ring shape in a bottom view (see FIG. 3C), has an outer diameter that fits into the concave portion of the flange portion 133, and a shaft holding member 138 at the center portion. An insertion port 137d for inserting the is opened.
In this embodiment, a portion facing a later-described valve seat portion 117 on which the valve body 130 is seated, that is, a lower peripheral portion 137c of the seat portion 137 is formed to be thicker than the other portions. ), The peripheral portion 137c protrudes downward from the lower end of the flange portion 133 in a state where the seat portion 137 is fitted in the concave portion of the flange portion 133. Thereby, the seating part 137 adheres to the valve seat part 117, and the sealing performance is improved. Moreover, since the part contact | abutted to the valve seat part 117 is thickened, durability also improves.
The insertion port 137d has an inner diameter set smaller than the inner diameter of the connecting portion 136, and engages with a small diameter portion 138b described later of the shaft holding member 138.

  The connecting portion 136 has a cylindrical shape, and integrally connects the top portion 135 and the seating portion 137 as described above. A shaft holding member 138 is inserted and held in a hollow portion surrounded by the inner peripheral surface 136b and the curved concave bottom surface 135b of the top portion 135.

  As shown in FIGS. 3B and 4, the shaft holding member 138 has a stepped columnar shape in which the upper part has a curved convex shape and the lower part has a small diameter, and the bottom surface will be described later. A bottomed insertion hole 138a into which the distal end portion of the shaft 140 is inserted is formed. As described above, the shaft holding member 138 is inserted into the hollow portion of the buffer member 134 from the insertion port 137d of the seating portion 137, and the insertion port 137d of the seating portion 137 is engaged with the small diameter portion 138b of the lower portion thereof. Thus, it is held in the hollow part so as not to fall off.

Again, a description will be given with reference to FIG.
The valve seat 116 disposed on the bottom surface side of the valve body 130 is provided integrally with a partition wall 115 that partitions the primary chamber 110a and the secondary chamber 120a, and the inner space of the primary chamber 110a extends from the bottom of the partition wall 115. Protrudes toward. The valve seat 116 has a cylindrical shape and is formed so as to be reduced in diameter toward the upper end. An annular valve seat portion 117 on which a seat portion 137 (peripheral portion 137a, hereinafter the same) of the valve body 130 is seated is provided at the distal end portion of the valve seat 116. The valve seat portion 117 is formed flat so as to be in close contact with the seat portion 137 of the valve body 130. Further, the valve seat portion 117 may be formed in a round shape, for example, in order to improve the adhesion.

A recess 112 is provided on the upper wall of the primary chamber body 110, and the upper end of the return spring 113 that biases the valve body 130 toward the valve seat 117 is held in the recess 112.
As described above, the return spring 113 is contracted between the upper surface of the flange portion 132 of the valve body 130 and the recess 112, and the valve body 130 is closed in a state in which the valve body 130 is closed as will be described later. The seating portion 137 is urged so as to seat on the valve seat portion 117 with good airtightness. Due to the biasing of the return spring 113, when the valve is closed, the primary chamber 110a and the secondary chamber 120a are blocked from being incapable of communicating (incapable of gas flow).
Further, when the valve body 130 described later is driven and displaced upward, the concavely convex top portion 135 of the valve body 130 comes into contact with the concave portion 112. That is, when the valve body 130 is displaced upward by the shaft 140 as will be described later, the top portion 135 comes into contact with the concave portion 112, and the shaft 140 moves upward with the contact of the top portion 135. Is configured to stop. The contact surface of the concave portion 112 with the top portion 135 is formed flat. However, the present invention is not limited to this, and the concave surface may be formed in a curved convex shape so that the contact area at the time of contact is small. It may be formed in a curved concave shape so as to improve the holdability.

  The secondary chamber body 120 is continuously provided in the lower part of the primary chamber body 110 via the partition wall 115, and a lead-out port to which piping leading to a diluter 33 (see FIG. 1, the same applies hereinafter) to be described later is connected. 121. That is, when the valve element 130 is driven to open and the anode off gas flows into the secondary chamber 120a from the primary chamber 110a via the valve element 130, the anode off gas flowing into the secondary chamber 120a is piped from the outlet port 121. To be sent to the diluter 33. In the present embodiment, the outlet port 121 is provided in the direction opposite to the introduction port 111 described above, that is, in the direction in which the piping leading to the diluter 33 can be connected.

In addition, a sealing member (not shown) is attached to the connection portion of each of the introduction port 111 and the outlet port 121 with each pipe, and the airtightness of the flowing anode off-gas is maintained.
Further, the inside of the primary chamber body 110 and the secondary chamber body 120 may be coated with fluorine. Since the fluorine coating has a water repellent effect of repelling moisture, it is difficult for moisture to stay inside the primary chamber body 110 and the secondary chamber body 120, and drainage can be improved.

  A shaft 140 that is driven by a solenoid 150 and whose tip is fixed to the insertion hole 138 a of the valve body 130 (shaft holding member 138) passes through the secondary chamber body 120. A diaphragm 160 made of an elastic member (for example, a material such as rubber) that is engaged with the shaft 140 and bends following the displacement operation of the shaft 140 is provided between the diaphragm 140 and the shaft 140.

  The diaphragm 160 is an annular member that surrounds the periphery of the shaft 140, and has an inner peripheral edge 161 attached to the flange portion 141 of the shaft 140, and a thin-walled shape that extends radially outward from the inner peripheral edge 161. The skirt portion 162 includes an outer peripheral edge portion 163 formed on the outer peripheral portion of the skirt portion 162.

The inner peripheral edge portion 161 is formed to be thicker than the skirt portion 162. The flange portion 141 and a stepped tip portion 143 provided on the bottomed cylindrical holding member 142 attached to the shaft 140. , The shaft 140 is locked.
The skirt portion 162 is formed in a thin shape as described above, and has a curved convex shape that protrudes toward the valve body 130 side. Such a skirt portion 162 can be flexed following the displacement operation of the shaft 140, and the stroke length of the shaft 140 is increased in combination with the diaphragm 160 having a large diameter as described above. Contributes to setting.

  The outer peripheral edge portion 163 is formed to be thicker than the skirt portion 162, and is attached to an upward annular groove 123 provided in the bottom wall 122 of the secondary chamber body 120. Is sandwiched between.

  By providing such a diaphragm 160, the space between the secondary chamber body 120 and the shaft 140 is sealed, and the airtightness inside the secondary chamber body 120 is suitably maintained.

  On the back surface side (solenoid 150 side) of the skirt portion 162, a projection portion 152 is provided that can be inserted into a recess on the back surface side of the skirt portion 162 and restricts deformation in which the unevenness of the skirt portion 162 is reversed. .

The projecting portion 152 is provided integrally with a fixed core 151 to be described later of the solenoid 150 and is formed in an annular shape below the skirt portion 162 so as to surround the shaft 140. The tip portion 153 of the protrusion 152 is formed in a round shape, and is formed in a semicircular cross section in this embodiment.
Note that a DLC film (Diamond Like Carbon) or the like may be formed on the protrusion 152 to reduce the frictional resistance with the skirt 162.

The solenoid 150 is formed by a fixed core 151 disposed so as to close the upper end portion of the casing 154, a bobbin 155 disposed inside the casing 154 and wound with a coil 155a, and an exciting action of the coil 155a. A cylindrical movable core 156 that is displaced in the axial direction of the shaft 140 and a spring 157 that is interposed between the movable core 156 and the lower portion of the casing 154 and biases the movable core 156 toward the fixed core 151. .
Further, a cap 159 provided with a moisture permeable waterproof material 158 is attached to the lower side of the casing 154.

The movable core 156 is a cylindrical member made of a magnetic metal material, and is disposed so as to be able to be inserted along the inner wall surface of the bobbin 155. The movable core 156 can be displaced in the axial direction of the shaft 140 by the exciting action of the coil 155a. . That is, the movable core 156 is attracted to the fixed core 151 when the coil 155a is excited, and is displaced upward against the urging force of the return spring 113 (see FIG. 2). Thereby, the valve body 130 is pushed upward.
A through hole 156a is formed in the substantially central portion of the movable core 156 along the axial direction, and the lower end 140a of the shaft 140 is inserted into and fixed to the through hole 156a.
The upper end portion of the movable core 156 is formed in a taper shape that tapers upward, and the lower end portion of the fixed core 151 that is opposed thereto is formed in a reverse taper shape corresponding thereto, By this interaction, a thrust is applied to the movable core 156 under the excitation action.

  A stepped portion 151a protruding upward is provided on the upper surface of the fixed core 151, and a projecting portion 152 is formed in an annular shape along the inner peripheral portion of the stepped portion 151a. Further, the stepped portion 151 a is configured to sandwich the outer peripheral edge portion 163 of the diaphragm 160 between the annular groove 123 of the bottom wall 122 of the secondary chamber body 120 as described above.

  The shaft 140 has a lower end 140 a side fitted into the hollow portion of the movable core 156 and fixed, and an upper end 140 b side inserted into the insertion hole 138 a of the valve body 130 and fixed. A flange portion 141 for fixing the inner peripheral edge portion 161 of the diaphragm 160 to the pressing member 142 is formed at a substantially central portion in the axial direction of the shaft 140.

  In addition, you may comprise so that the sliding resistance at the time of the shaft 140 being displaced may be reduced by giving a fluorine coating etc. to the outer peripheral surface of the shaft 140. By doing in this way, abrasion of the shaft 140 can be reduced and durability can be improved. At the same time, it is possible to suppress the generation of wear powder when the shaft 140 is displaced. Since the fluorine coating has a water repellent effect of repelling moisture, moisture does not adhere to the outer peripheral surface of the shaft 140, rusting of the shaft 140 can be prevented, and durability of the shaft 140 can be improved.

A ventilation path 154a is formed in the lower part of the casing 154, and a cap 159 is attached to the opening 154b of the ventilation path 154a. The air passage 154 a is a horizontal hole that opens to the surface of the casing 154 and the shaft side chamber 156 b that slideably holds the shaft 140, and serves to communicate the shaft side chamber 156 b with the outside of the casing 154.
In the present embodiment, the casing 154 has a shape undercut to the movable core 156 side below the bobbin 155, and the cap 159 is suitably fitted in this undercut region. Therefore, the cap 159 does not protrude to the side of the secondary chamber body 120, and space saving is achieved.

The cap 159 includes a lid portion 159a provided with a ventilation opening 159c on a side portion and a hook portion 159b provided on the lid portion 159a, and a moisture-permeable and waterproof material 158 is formed in a passage formed in the lid portion 159a. Is arranged. The moisture permeable and waterproof material 158 prevents entry / exit of water while allowing entry / exit of air. For example, a well-known Gore-Tex (registered trademark) can be used.
By disposing the cap 159 having such a moisture-permeable and waterproof material 158, air or dust is prevented from entering (intruding) into the solenoid 150, and air is introduced into the ventilation path 154a via the moisture-permeable and waterproof material 158. Thus, smooth sliding of the movable core 156 is realized.

<Cathode system>
Returning to FIG. 1, the description will be continued.
The cathode system includes a compressor 31 (oxidant gas supply means, scavenging means), a humidifier 32, and a diluter 33 (gas treatment device).

The compressor 31 is connected to the inlet of the cathode channel 12 via the humidifier 32. When operated according to a command from the ECU, the compressor 31 takes in oxygen-containing air and supplies the air to the cathode channel 12. The compressor 31 functions as a scavenging means for scavenging the fuel cell stack 10 when scavenging.
The compressor 31 operates using a fuel cell stack 10 and a high-voltage battery (not shown) that charges and discharges power generated by the fuel cell stack 10 as a power source.

  The humidifier 32 includes a hollow fiber membrane or the like that exchanges moisture between the air that travels from the compressor 31 toward the cathode flow path 12 and the air that travels toward the cathode flow path 12 and the humid cathode offgas.

  The outlet of the cathode channel 12 is connected to a diluter 33 so that the humid cathode off gas discharged from the cathode channel 12 (cathode) is supplied to the diluter 33.

  The diluter 33 is a container that mixes the anode off-gas introduced from the purge valve 24 and the cathode off-gas (dilution gas) from the compressor 31 and dilutes the hydrogen in the anode off-gas with the cathode off-gas. The mixed gas generated by the diluter 33 is discharged outside the vehicle.

Next, the operation of the scavenging gas discharge valve 100 to which the valve device of this embodiment is applied will be described.
When the ECU determines that the fuel cell stack 10 is likely to be frozen when the system is stopped, the compressor 31 is actuated by an ECU command, and the scavenging gas discharge valve 100 is opened together with a scavenging gas introduction valve (not shown). .

  Then, the scavenging gas (air) from the compressor 31 is pushed into the anode flow path 11 and the cathode flow path 12, thereby pushing out moisture (water vapor, condensed water, etc.) in the anode flow path 11 and the like, and the fuel cell stack. 10 is scavenged.

  The water pushed out from the anode flow path 11 is discharged out of the vehicle through the scavenging gas discharge valve 100 and the diluter 33 together with the scavenging gas. On the other hand, the water pushed out from the cathode channel 12 is discharged out of the vehicle through the diluter 33 together with the scavenging gas.

  During such scavenging, in the scavenging gas discharge valve 100, the movable core 156 is attracted to the fixed core 151 and moved upward by the coil 155a excited by a command from the ECU, and the shaft 140 moved accordingly. As a result, the valve body 130 is separated from the valve seat portion 117. At this time, the top portion 135 of the valve body 130 elastically contacts the concave portion 112 of the upper wall, and the upward movement of the valve body 130 is stopped by this contact and the valve body 130 is opened.

As a result, the high-pressure anode off-gas containing moisture pushed out from the anode channel 11 flows into the primary chamber 110a from the introduction port 111, and further flows into the secondary chamber 120a from the primary chamber 110a and discharges from the outlet port 121. Will come to be.
At this time, even if moisture such as water vapor or condensed water passes along with the anode off-gas, the valve body 130 has a substantially hemispherical shape at the top portion 135, so that these do not stay on the top portion 135, Freezing and sticking of the valve body 130 due to moisture retention (liquid accumulation) is preferably prevented.

  Further, when the valve is closed, the coil 155a is de-energized by the ECU, the top portion 135 of the valve body 130 is suitably separated from the recess 112 by the return spring 113, and then the valve body 130 is seated on the valve seat 116. Thereby, between the primary chamber 110a and the secondary chamber 120a is interrupted | blocked, scavenging is complete | finished.

  According to the valve device of the present embodiment described above, the valve body 130 is formed of a curved convex elastic member whose top portion 135 can be elastically brought into contact with the upper wall. Even if moisture such as water vapor or condensed water passes sometimes, it can be prevented that these remain on the top 135 of the valve body 131. As a result, freezing and sticking of the valve body 131 due to moisture retention can be suitably prevented. Therefore, stable opening and closing of the valve body can be maintained over a long period of time, which contributes to the realization of a fuel cell system having excellent durability and excellent reliability.

  In addition, since the top portion 135 is formed of a curved convex elastic member that can elastically abut against the upper wall, compared to the case where the top portion 135 is formed flat, adhesion to the upper wall is improved. It is possible to suitably prevent the valve body 131 from adhering to the upper wall due to the freezing of moisture.

  In addition, since the top portion 135 is formed of a curved convex elastic member that can elastically contact the upper wall, the impact is relieved when contacting the upper wall, and the valve body 131. The abutment noise is reduced, and silence can be realized.

  Further, since the seat portion 137 of the valve body 131 is formed of an elastic member integrated with the top portion 135, the rigidity is increased and the number of parts can be reduced. Thereby, the part cost and the assembly cost are reduced, and the manufacturing cost can be reduced.

  Moreover, the valve body 131 is formed in the cylindrical shape which has a hollow part, and can achieve weight reduction. Since the cushioning member 134 made of an elastic member is provided integrally with the top portion 135 side and the seating portion 137 side through the hollow portion, it is arranged in a well-balanced manner, and the operability of the valve body 131 is improved.

Further, by providing the protrusion 152, even if the skirt 162 of the diaphragm 160 is deformed toward the back side due to the pressure of the fluid at the time of valve opening or the like, the protrusion 152 is in the deformed portion on the back side. From this, deformation of the diaphragm 160 can be suppressed. Therefore, the state in which the skirt portion 162 of the diaphragm 160 is raised toward the valve body 130 can be suitably maintained, and it is not necessary to ensure the rigidity of the diaphragm 160 by forming the diaphragm 160 thickly. That is, the diaphragm 160 can be formed thin.
Therefore, the stroke length of the shaft 140 can be increased to ensure the flow rate, and the valve body 130 can be smoothly moved with good response.

  Further, since the cap 159 having the moisture permeable waterproof material 158 is attached to the opening 154b of the air passage 154a that communicates the shaft side chamber 156b with the outside of the secondary chamber body 120, the shaft side chamber 156b is thus moved to the shaft side chamber 156b. It is possible to prevent water and the like from entering while allowing the air to enter and exit. Therefore, a stable displacement operation of the shaft 140 can be ensured, and the operability of the valve body 131 is improved.

  In the above-described embodiment, the entire top portion 135 has a substantially hemispherical shape, but the present invention is not limited to this. For example, a portion of the top portion 135 that contacts the recess 112 on the upper wall of the primary chamber 110a. Only a curved convex shape may be formed.

  Further, although the buffer member 134 is formed by connecting the top portion 135 and the seating portion 137 by the connecting portion 136, the cushioning member 134 is not limited to this, but the top portion 135 and the seating portion 137 are formed separately and the base portion is formed. You may comprise so that 131 may be mounted | worn.

  In the above-described embodiment, an example in which the valve device is used for the scavenging gas discharge valve 100 has been described. However, the present invention is not limited to this, and the scavenging gas introduction valve may be used for the purge valve 24. You may use for etc.

  In addition, the solenoid 150 is exemplified as the drive mechanism, but the present invention is not limited to this, and other drive mechanisms, for example, a coil member is disposed between the magnetic pole surfaces of the permanent magnets that are spaced apart from each other and energized. Thus, it is possible to employ a voice coil type driving means that drives the shaft 140 in the axial direction using electromagnetic force.

  Furthermore, in the above-described embodiment, the case where the fuel cell system 1 is mounted on a fuel cell vehicle has been illustrated. However, for example, a fuel cell system mounted on a motorcycle, a train, or a ship may be used. Further, it may be a fuel cell system used for stores, offices and the like.

It is a figure which shows the function of the fuel cell system using the scavenging gas discharge valve as a valve apparatus which concerns on one Embodiment of this invention. It is sectional drawing of a scavenging gas discharge valve. (A) is a top view of a valve body, (b) is sectional drawing of a valve body, (c) is a bottom view. It is a disassembled perspective view of a valve body.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Fuel cell stack 100 Scavenging gas discharge valve 110 Primary chamber body 110a Primary chamber 116 Valve seat 117 Valve seat part 120 Secondary chamber body 120a Secondary chamber 130 Valve body 134 Elastic member 135 Top part 136 Connection part 137 Seating part 138 Shaft holding member 140 Shaft 150 Solenoid 154a Ventilation path 154b Opening 156b Shaft side chamber 158 Moisture permeable waterproof material 159 Cap

Claims (5)

A body provided with a primary chamber into which fluid is introduced and a secondary chamber into which fluid is derived;
A shaft extending from the secondary chamber side to the primary chamber side and displaced in the axial direction by a drive mechanism;
A valve body that communicates or blocks between the primary chamber and the secondary chamber in accordance with the displacement of the shaft;
The valve body is arranged in the primary chamber, and is configured to open by being displaced toward the wall of the primary chamber forming the primary chamber,
The valve device is characterized in that at least a top portion thereof is formed of a curved convex elastic member that can elastically contact the wall.   2. The valve device according to claim 1, wherein a seating portion of the valve body is formed of an elastic member integrated with the top portion.   The valve body is formed by attaching an elastic member to a concentric cylindrical base portion having a hollow portion, and the elastic member is provided integrally with the top portion side and the seating portion side through the hollow portion. The valve device according to claim 2, wherein A diaphragm that is provided between the wall of the secondary chamber and the shaft and is bent by the shaft and following the displacement operation of the shaft;
The diaphragm has a curved skirt that protrudes toward the valve body side,
A protrusion that is provided on the back surface side of the skirt portion, which is the drive mechanism side, so as to be insertable into a recess on the back surface side of the skirt portion, and restricts the skirt portion from being deformed toward the back surface side. The valve device according to any one of claims 1 to 3, further comprising a portion. The body on the side of the secondary chamber opens to a surface thereof and a shaft side chamber formed on the side of the end of the shaft, and vents communicate the shaft side chamber with the outside of the body on the side of the secondary chamber. A road is formed,
A cap having a moisture-permeable and waterproof material that prevents air from entering and exiting is attached to the opening of the air passage formed on the surface of the body on the secondary chamber side. The valve device according to any one of claims 1 to 4, wherein the valve device is characterized.

Images