Eccentric valve

Abstract

An eccentric valve (181) comprising: a valve seat (13) with a valve opening (16) and a seat surface (17) formed at an edge of the valve opening (16); a valve element (14) formed with a sealing surface (18) on an outer circumference corresponding to the seat surface (17);a rotatable shaft (15) integrated with the valve element (14) for rotating the valve element (14), and the rotatable shaft (15) has a central axis extending parallel to a radial direction of the valve element (14), wherein the central axis of the rotatable shaft (15) is arranged eccentrically from a center of the valve opening (16) in another radial direction of the valve opening (16), and the sealing surface is arranged eccentrically from the central axis of the rotatable shaft (15) towards an extension direction of the central axis of the valve element (14), wherein the eccentric valve further comprises: a drive mechanism for generating a drive force to rotate the rotatable shaft (15) in a direction towards the opening of the valve; a drive force receiving part integrally integrated with the rotatable shaft (15) for receiving the drive force;a bearing arranged in a position between the valve element (14) and the drive force receiving part in the direction of the central axis of the rotatable shaft (15) for supporting the rotatable shaft (15);and a return spring (40) for generating a return spring force (Fs1) to rotate the rotatable shaft (15) in a direction to close the valve, wherein, during a non-operation of the actuating mechanism (32), the eccentric valve generates a force (Fs4) pushing in a separating direction, so that the rotatable shaft (15) tilts about the bearing (37) as pivot point and the valve element (14) is pushed in a direction away from the valve seat (13), wherein the force pushing in the separating direction is a force based on the return spring force (Fs1) and acts in a direction perpendicular to the central axis (Lj) of the bearing (37, 38), and either the valve element (14) or the valve seat (13) has a sealing element (21) to seal between the valve element (14) and the valve seat (13) during the non-operation of the actuating mechanism (32).

Description

Technical FieldThe present invention relates to an eccentric valve (a double eccentric valve) which is a valve for use as a flow control valve in which a valve element is disposed with its center of rotation (a rotatable shaft) positioned eccentrically from a center of a valve opening of a valve seat and a sealing surface of the valve element is positioned eccentrically from the rotatable shaft.Prior ArtFor a flow control valve, Patent Document 1 discloses a flow opening / closing valve configured to be brought into a valve closed position by rotating a valve element in contact with a movable seat and into a valve open position by rotating the valve element away from the movable seat. Patent Document 2 relates to a double-eccentric valve including a drive mechanism that generates a drive force to rotate a rotation shaft in such a direction as to open the valve, a drive force receiving unit that is integrally formed with the rotation shaft to receive the drive force, a bearing that is interposed between a valve assembly and the drive force receiving unit in the direction of the central axis of the rotation shaft to hold the rotation shaft, and a return spring that generates a return spring force to rotate the rotation shaft in such a direction as to close the valve. Patent Document 3 relates to a double eccentric valve including a valve seat having a seating surface on a valve hole, a valve body having a sealing surface, a flow path in which the valve seat and the valve body are disposed, and a rotation shaft rotating the valve body fixed to a fixing part of the rotation shaft.Related Art DocumentPatent DocumentsPatent Document 1: Japanese Unexamined Patent Application Publication No. 2012-72 793 APatent Document 2: DE 11 2015 003 071 T5Patent Document 3: U.S. Pat. No. 9,951,876 B2SUMMARY OF THE INVENTIONProblems to be Solved by the InventionHowever, in the flow opening / closing valve of Patent Document 1, the valve element is in contact with the movable seat only in the valve closed position where a drive source is not operated. Thereby, a sealing property between the valve element and the movable seat in the valve closed position cannot be improved (a sealing function cannot be satisfied).The present invention has been made to solve the above problems, and has an object to provide an eccentric valve capable of improving a sealing property in a valve closed position.Means for Solving the ProblemsTo achieve the above object, an aspect of the invention provides an eccentric valve, comprising: a valve seat having a valve hole and a seating surface formed at an edge of the valve hole; a valve element formed with a sealing surface on an outer periphery corresponding to the seating surface; a rotatable shaft installed with the valve element for rotating the valve element, and the rotatable shaft has a central axis extending parallel to a radial direction of the valve element, wherein the central axis of the rotatable shaft is arranged eccentrically from a center of the valve opening in another radial direction of the valve opening, and the sealing surface is arranged eccentrically from the central axis of the rotatable shaft toward an extending direction of the central axis of the valve element, wherein the eccentric valve further comprises: a driving mechanism for generating a driving force for rotating the rotatable shaft in a direction for opening the valve; a driving force receiving part installed integrally with the rotatable shaft for receiving the driving force; a bearing for supporting the rotatable shaft, the bearing being disposed at a position between the valve member and the driving force receiving part toward the central axis of the rotatable shaft; and a return spring for generating a return spring force to rotate the rotatable shaft in a direction for closing the valve, wherein, during non-operation of the drive mechanism, the eccentric valve generates a force urging in a separating direction such that the rotatable shaft inclines about the bearing as a fulcrum and the valve element is urged in a direction away from the valve seat, wherein the force urging in the separating direction is a force based on the return spring force and acting in a direction perpendicular to the central axis of the bearing, and either the valve element or the valve seat includes a sealing member to seal between the valve element and the valve seat during non-operation of the drive mechanism.According to this configuration, during non-operation of the drive mechanism, the sealing member seals between the valve seat and the valve element. As a result, a sealing property in the closed valve position can be improved.Preferably, the sealing member of the foregoing embodiment includes a deformable portion having a front end which comes into contact with the valve element or the valve seat during non-operation of the driving mechanism and which is deformed when compressed by the valve element or a valve seat during operation of the driving mechanism, and deformation of the deformable portion during operation of the driving mechanism is smaller than deformation of the deformable portion during plastic deformation.According to the above configuration, the deformable portion of the seal member is not excessively compressed by the valve member. Thus, abrasion and wear of the seal member can be reduced.Preferably, when the drive mechanism is to be switched from an operating state to a non-operating state, the drive mechanism of the aforementioned configuration is switched to the non-operating state after a pressure on the valve element on a side facing the valve seat reaches a predetermined negative pressure.According to the above embodiment, the drive mechanism is operated until the pressure applied to the valve element on the valve seat facing side (a valve seat side) reaches the predetermined negative pressure. After the pressure on the valve seat side applied to the valve element reaches the predetermined negative pressure, the drive mechanism is not operated and the valve element moves toward the valve seat by the negative pressure generated on the valve seat side opposite to the valve element. Thereby, a high sealing property between the valve seat and the valve element can be achieved.In the aforementioned configuration, the eccentric valve is preferably configured to execute a control mode during operation of the drive mechanism, the control mode including a pressure regulating mode for controlling an open area of the valve opening and a seal control mode for controlling rotation of the valve element near a fully closed position of the valve element.According to the above embodiment, the rotation of the valve element near a fully closed position of the valve element is executed only in the seal control mode. Thereby, the number of times the valve element and the seal element slide on each other can be reduced. Thus, abrasion and closing of the sealing member can be reduced.Preferably, a rotational speed of the valve element according to the aforementioned configuration in the seal control mode is slower than a rotational speed of the valve element in the pressure regulating mode.According to the above configuration, the amount of sliding of the valve element with respect to the seal element in the seal control mode can be reduced. This can reduce abrasion and wear of the sealing element.Preferably, in the aforementioned configuration, the valve element and the sealing element are not in contact with each other in the pressure regulating mode.According to the above configuration, in which the valve element and the seal element are not in contact with each other in the pressure regulating mode that is executed again and again, the number of times the valve element and the seal element slide against each other can be minimized. This allows abrasion and wear of the sealing element to be reduced.Preferably, in the above configuration, the eccentric valve includes a passage through which air flows into a fuel cell system, and when the fuel cell system drives an air pump for controlling the flow rate of the air in response to a request for a regenerative brake, an opening degree of the valve element is maintained at an opening degree within an opening degree range determined in the seal control mode.According to the above configuration, the frequency of sliding of the valve element and the seal element can be reduced. Therefore, excessive electric power generated at the time of request by a regenerative brake can be consumed for the operation of an air pump while suppressing abrasion of the seal member.Effects of the InventionAccording to an eccentric valve of the present invention, a sealing property in a valve closed position can be improved.Brief Description of the DrawingsFIG. 1 is a schematic configuration view of a fuel cell system; FIG. 2 is a front view of an integrated valve in an embodiment; FIG. 3 is a top view of the integrated valve in the embodiment; FIG. 4 is a partially cut-away perspective view of a valve unit in a valve closed position (a full closing position) in which a valve element is in contact with a valve seat; FIG. 5 is a partially cut-away perspective view of the valve unit in the fully opened position in which the valve element is separated furthest from the valve seat; FIG. 6 is a side view of the valve seat, the valve member, and a rotatable shaft in a fully closed position of a flow control valve; FIG. 7 is a cross-sectional view taken along line A-A in FIG. 6 ; FIG. 8 is a cross-sectional view taken along a line B in FIG. 2 ; FIG. 9 is a cross-sectional view taken along a line C-C in FIG. 2 ; FIG. 10 is a front view showing a state in which a terminal frame has been detached from a valve housing; FIG. 11 is an enlarged view (a partially cut view) of a main transmission, a return spring, and an intermediate transmission during non-operation of an engine; FIG. 12 is a schematic view showing forces acting on the main transmission during non-operation of the motor as viewed from a main transmission side direction toward a central axis of the rotatable shaft; FIG. 13 is a schematic view showing the valve seat, the valve element, the rotatable shaft, the bearings, and the main gear, which is a cross section taken along line D-D in FIG. 12 ; FIG. 14 is a schematic view showing forces acting on the main transmission during operation of the motor as viewed from a main transmission side direction toward a central axis of the rotatable shaft; FIG. 15 is a schematic view showing the valve seat, the valve element, the rotatable shaft, the bearings, and the main gear, which is a cross section taken along line E-E in FIG. 14 ; FIG. 16 is a diagram corresponding to FIG. 15 and illustrates a case where the driving force of the motor is set larger than that in FIG. 15 ; FIG. 17 is an enlarged view (a partially cut view) of the main transmission, the return spring, the intermediate transmission, and the surrounding parts at an opening degree α of the valve during operation of the engine; FIG. 18 is a diagram corresponding to FIG. 16, and illustrates a case where the driving force of the motor is set larger than that in FIG. 16 ; FIG. 19 is an enlarged view (a partially cut view) of the main transmission, the return spring, the intermediate transmission, and the surrounding parts at an opening degree β of the valve during operation of the engine; FIG. 20 is a graph showing a relationship between opening degree of the valve and open area; FIG. 21 is a view showing a rubber seat; FIG. 22 is a view showing a rubber seat in an altered example; FIG. 23 is a view showing a rubber seat in another modified example; FIG. 24 is a cross-sectional view of the valve seat and the valve element and the surrounding parts when the opening degree of the valve element is an angle A; FIG. 25 is a cross-sectional view of the valve seat and the valve element and the surrounding parts when the opening degree of the valve element is an angle B;FIG. 26 is a control flow diagram in a second embodiment; FIG. 27 is a timing chart in the second embodiment;FIG. 28 is a control flow chart in a third embodiment; FIG. 29 is a timing chart in the third embodiment;FIG. 30 is a control flow chart in a fourth embodiment; and FIG. 31 is a timing chart in the fourth embodiment.Embodiments for Carrying Out the Invention[First Embodiment]The present invention is applied to, for example, an integrated valve of an air system in a fuel cell system. Therefore, the fuel cell system will be described first, and then the integrated valve to which an eccentric valve of the invention is applied will be described later.< Of Fuel Cell System>A fuel cell system 101 is mounted in an electric vehicle and used to provide electric power to a drive motor (not shown) of the vehicle. As shown in FIG. 1, the fuel cell system 101 includes a fuel cell (FC stack) 111, a hydrogen system 112, and an air system 113.The fuel cell 111 generates power with the acquisition of supplied fuel gas and supplied oxidizing gas. In the present embodiment, the fuel gas is hydrogen gas and the oxidizing gas is air. Specifically, the fuel cell 111 generates power when drawing hydrogen gas supplied from the hydrogen system 112 and air supplied from the air system 113. The electric power generated in the fuel cell 111 is supplied to a drive motor (not shown) via an inverter (not shown).The hydrogen system 112 is provided on an anode side of the fuel cell 111. The hydrogen system 112 includes a hydrogen supply line 121, a hydrogen discharge line 122, and a filling line 123. The hydrogen supply line 121 is a flow passage for supplying hydrogen gas from a hydrogen tank 131 to the fuel cell 111. The hydrogen discharge line 122 is a flow passage for discharging hydrogen gas discharged from the fuel cell 111 (hereinafter, also referred to as "hydrogen off gas", respectively). The filling pipe 123 is for filling hydrogen gas into the hydrogen tank 131 via a filling port 151.The hydrogen system 112 includes, with respect to the hydrogen supply line 121, a main stop valve 132, a high-pressure regulator 133, an intermediate-pressure relief valve 134, a pressure sensor 135, an injector 136, a low-pressure relief valve 137, and a pressure sensor 138, which are arranged in this order from the hydrogen tank 131. The main stop valve 132 is a valve for switching between supply and supply shut-off of hydrogen gas from the hydrogen tank 131 to the hydrogen supply pipe 121. The high pressure regulator 133 is a pressure regulating valve for reducing the pressure of the hydrogen gas. The intermediate pressure relief valve 134 is a valve that can open when the pressure in the hydrogen supply line 121 between the high pressure regulator 133 and the injector 136 becomes equal to or higher than a predetermined pressure to regulate the pressure below the predetermined pressure. The pressure sensor 135 is a sensor for detecting the pressure in the hydrogen supply line 121 between the high-pressure regulator 133 and the injector 136. The injector 136 is a mechanism for regulating the flow rate of the hydrogen gas. The low-pressure relief valve 137 is a valve that can open when the pressure in the hydrogen supply line 121 between the injector 136 and the fuel cell 111 becomes equal to or higher than a predetermined pressure to regulate the pressure below the predetermined pressure. The pressure sensor 138 is a sensor for detecting the pressure in the hydrogen supply line 121 between the injector 136 and the fuel cell 111.The hydrogen system 112 also includes, with respect to the hydrogen discharge line 122, a gas-liquid separator 141 and a vent discharge valve 142 arranged in this order from the fuel cell 111. The gas-liquid separator 141 is a means for separating moisture from the hydrogen off-gas. The purge discharge valve 142 is a valve for switching between extraction and shut-off of the hydrogen off gas and the moisture from the gas-liquid separator 141 to a diluter 182 of the air system 113.The air system 113 is provided on a cathode side of the fuel cell 111. This air system 113 includes an air supply line 161, an air discharge line 162, and a bypass line 163. The air supply line 161 is a flow passage for supplying air outside the fuel cell system 101 into the fuel cell 111. The air discharge line 162 is a flow passage for discharging air discharged from the fuel cell 111 (hereinafter, also referred to as "air off gas", respectively). The bypass line 163 is a flow passage for allowing air to flow from the air supply line 161 to the air discharge line 162 without passing through the fuel cell 111.The air system 113 further includes, with respect to the air supply pipe 161, an air cleaner 171, an air pump 172, an intercooler 173, and a sealing valve 174 arranged in this order. The air cleaner 171 is a means for purifying the air taken out outside the fuel cell system 101 for this air. The air pump 172 is a device for regulating a flow rate of the air. The air charge cooler 173 is a means for cooling air. The seal valve 174 is a valve for switching between supply and shut-off of air to the fuel cell 111.With respect to the air discharge line 162, the air system 113 further includes an outlet integrated valve 181 and a diluter 182 arranged in this order from the fuel cell 111.The outlet integrated valve 181 is a valve (a valve having an air seal function) for switching between suction and shut off of air off gas from the fuel cell 111, and also a valve (a valve having a flow rate control function) for controlling the amount of discharged air off gas from the fuel cell 111. In the present embodiment, the eccentric valve of the present invention is provided for the integrated valve 181.The diluter 182 is a means for diluting the hydrogen off-gas exhausted from the hydrogen exhaust passage via the air off-gas and air flowing through the bypass line 163.The bypass line 163 of the air system 113 further includes a bypass valve 191. The bypass valve 191 is a valve for controlling the flow rate of air in the bypass line 163.The fuel cell system 101 further includes a controller 201 for controlling the system. Specifically, the controller 201 is configured to control each component or device of the fuel cell system 101. In addition, the fuel cell system 101 also includes a cooling system (not shown) for cooling the fuel cell 111. In the present embodiment, the controller 201 is, for example, an ECU.In the fuel cell system 101 configured as above, the hydrogen gas supplied via the hydrogen supply line 121 to the fuel cell 111 is consumed in the fuel cell 111 to generate electric power, and thereafter, exhausted to the outside of the fuel cell system 101 as hydrogen off-gas from the fuel cell 111 through the hydrogen discharge line 122 and the diluter 182. The air supplied from the air supply line 161 to the fuel cell 111 is consumed to generate electric power in the fuel cell 111, and thereafter, is exhausted to the outside of the fuel cell system 101 as air off gas from the fuel cell 111 through the hydrogen discharge line 122 and the diluter 182.< Of Integrated Valve>Next, the integrated valve 181 to which the eccentric valve of the present invention is applied will be described below.As shown in FIGS. 2 and 3, the integrated valve 181 includes a valve portion 2 and a drive mechanism portion 3. The valve portion 2 includes pipe portion 12 (see FIG. 8 ) having a passage 11 for allowing air (atmospheric air) to flow. In this passage 11 are disposed a valve seat 13, a valve element 14 and a rotatable shaft. The rotatable shaft 15 receives a driving force (torque) transmitted from the driving mechanism portion 3. The drive mechanism portion 3 includes a motor 32 and a speed reduction mechanism 33 (see FIGS. 8 and 9 ).As shown in FIGS. 4 and 5, the passage 11 is formed with a recess 10 in the form of a shoulder into which the valve seat 13 is fitted. The valve seat 13 has a round ring shape with a valve hole 16 formed in the center. The valve opening 16 is provided at its circumferential edge with an annular seating surface 17. the valve element 14 comprises a round disc-shaped region, the circumference of which has an annular sealing surface 18 which corresponds to the seating surface 17. The valve element 14 is formed integrally with the rotatable shaft 15 and rotatable together with the rotatable shaft 15.In the present embodiment, the valve seat 13 is provided with a rubber seat 21. The seat surface 17 is formed in this rubber seat 21. Details of the rubber seat 21 will be described later.In the present embodiment shown in FIGS. 4 and 5, the passage 11 formed on a side opposite to the valve element 14 and the rotatable shaft 15 with respect to the valve seat 13 is disposed on a side facing the fuel cell 111 (upstream of the air flow), while the passage 11 formed on a side closer to the valve element 14 and the rotatable shaft 15 with respect to the valve seat 13 is disposed on a side facing the diluter 182 (downstream of the air flow). In other words, according to the present embodiment, the air flows in the passage 11 from the valve seat 13 side to the valve element 14 side (the rotatable shaft 15).The central axis Ls of the rotatable shaft 15 extends, as shown in FIGS. 6 and 7, parallel to a radial direction of the valve element 14 (more specifically, the diameter of the disk-shaped portion of the valve element 14) and is disposed eccentrically from the central axis P 1 of the valve hole 16 to a radial direction side of the valve hole 16. The sealing surface 18 of the valve element 14 is disposed eccentrically from the central axis Ls of the rotatable shaft 15 to an extending direction of the central axis Lv of the valve element 14.By rotating the valve element 14 about the central axis Ls of the rotatable shaft 15, the valve element 14 is between a valve closed position in which the sealing surface 18 of the valve element 14 is in surface contact with the seat surface 17 and a fully open position in which the sealing surface 18 is furthest from the seat surface 17 (see FIG. 5 ).As shown in FIGS. 8 and 9, a valve housing 35 made of metal or plastic includes the passage 11 and the pipe portion 12. A closing frame 36 made of metal or plastic closes an open end of the valve housing 35. The rotatable shaft 15 includes a pin 15a at its distal end portion. Specifically, the pin 15 ais provided at an end of the rotatable shaft 15 in the direction of the central axis Ls (on the side near the valve element 14). The diameter of the pin 15a is smaller than the diameter of a portion of the rotatable shaft 15 not including the pin 15a. At the other end of the rotatable shaft 15 in the direction of the central axis Ls (on the side close to a main gear 41), a proximal end portion 15 bis provided.The distal end portion of the rotatable shaft 15 formed with the pin 15 ais a free distal end that is inserted and placed in the passage 11 of the pipe portion 12. The rotatable shaft 15 is supported in a cantilevered configuration by two spaced apart bearings, namely a first bearing 37 and a second bearing 38, such that the rotatable shaft 15 is rotatable with respect to the valve housing 35. The first bearing 37 and the second bearing 38 are each formed of a ball bearing. These first and second bearings 37 and 38 are disposed between the valve element 14 and the main gear 41 in the direction of the central axis Ls of the rotatable shaft 15 for rotatably supporting the rotatable shaft 15. In the present embodiment, the first bearing 37 is disposed at a position closer to the main transmission 41 relative to the second bearing. The valve element 14 is fixed by welding to the pin 15 ain the distal end portion of the rotatable shaft 15 and placed in the passage 11.The end frame 36 is secured to the valve housing by a plurality of clamps 39 (see FIGS. 2 and 3 ). As shown in FIGS. 8 and 9, the fan-shaped main gear 41 is fixed to the proximal end portion 15 bof the rotatable shaft 15. A return spring 40 that generates a return spring force Fs 1 (see FIG. 12 ) is provided between the valve housing 35 and the main transmission 41. The return spring force Fs 1 is a force for rotating the rotatable shaft 15 in a closing direction of the valve and urging the valve element 14 in a closing direction (i.e., toward a position where the valve opening degree θ, which will be described later, is "0").The return spring 40 is an elastic member made of a helically wound wire, and has a near-side hook 40 band a far-side hook 40 aat both ends. The far-side hook 40 aand the near-side hook 40 bare spaced apart from each other by a distance of about 180° in a circumferential direction of the return spring. The distal-side hook 40 ais disposed on a side of the valve housing 35 (on a distal side of the drawing sheet of FIG. 11 ) so as to contact a spring hook part 35 c(see FIG. 19 ) of the valve housing 35. In contrast, the near-side hook 40 bis disposed on a side of the main transmission 41 (on a near side of the drawing sheet of FIG. 11 ) so as to contact a spring hook part 41 cof the main gear 41.As shown in FIGS. 8, 9, 10 to 11, the main transmission 41 includes, among other things, a full close stopper portion 41 a, a gear portion 41 b, a spring hook part 41 c, and a spring guide portion 41 d. In the circumferential direction (counterclockwise in FIG. 11 ) of the main transmission 41, the stopper fully closed portion 41 a, the gear portion 41 b, and the spring hook part 41 care arranged in this order. The main transmission 41 is installed with the rotatable shaft 15 and configured to receive the driving force generated by the motor 32. The full closing stopper portion 41a is a portion abutting on the valve housing closing position stopper portion 35b when the valve opening degree θ is "0". The prime mover 41 is an example of "driving force receiving part" of the present invention.The valve opening degree θ is a rotation angle of the rotatable shaft 15 about the central axis Ls and corresponds to a rotation angle of the main gear 41 and an opening angle of the valve element 14.The gear portion 41b, as shown in FIG. 11, meshes with gear 42b of the small-diameter intermediate gear 42. The spring hook part is in contact with the near-side hook 40 bof the return spring 40, and receives the return spring force Fs 1 from the near-side hook 40 b(see FIG. 12 ).As shown in FIG. 9, the spring guide portion 41 dis disposed inside the coil return spring 40 for supporting the return spring 40. The spring guide portion 41 dis installed on the proximal end 15 bside of the rotatable shaft 15 with the rotatable shaft 15.The main transmission 41 includes, as shown in FIG. 9, a recess 41 ein which a substantially disk-shaped magnet 46 is mounted. Thereby, when the main gear 41 rotates together with the valve element 14 and the rotatable shaft 15, the magnet 46 is also rotated, thereby changing a magnetic field of the magnet 46. This magnetic field change of the magnet 46 is detected via a rotation angle sensor (not shown), so that the rotation angle of the main transmission 41 is detected as an opening degree of the valve element 14, that is, the opening degree of the main transmission 41.As shown in FIG. 8, the motor 32 is accommodated and fixed in a retaining recess 35a formed in the valve housing. The motor 32 generates a driving force for rotating the rotatable shaft 15 in a valve opening direction and a valve closing direction. The motor 32 is coupled to the rotatable shaft 15 via the speed reduction mechanism 33 for transmitting the driving force to open and close the valve element 14. Specifically, the output shaft 32 a(see FIG. 10 ) of the motor 32 is fixed to a motor gear 43. This motor gear 43 is connected to the main gear 41 through an intermediate gear 42 for transmitting the driving force.The intermediate gear 42 is a double gear having a large diameter gear 42a and the small diameter gear 42b, and is rotatably supported by the valve housing 35 via a shaft bolt 44. The diameter of the large-diameter gear 42 ais larger than the diameter of the small-diameter gear 42 b. The large diameter gear 42a is drivingly engaged with the motor 32, while the small diameter gear 42b is drivingly engaged with the main gear 41. In the present embodiment, the main transmission 41, the intermediate transmission 42, and the motor 32 constituting the speed reduction mechanism 33 are made of resin. As a result, weight savings are achieved in the present embodiment.The motor 32 is an example of a "drive mechanism" according to the present invention. The intermediate gear 42 (a drive transmission member) also transmits the driving force of the motor 32 to the rotatable shaft 15.In the integrated valve 181 in the above configuration, as will be mentioned in detail later, when the motor 32 is turned on, from a valve closed position (a position in which the entire circumference of the sealing surface 18 of the valve element 14 is in contact with the entire circumference of the seat surface 17 of the valve seat 13), as shown in FIG. 4, a force (the motor driving force Fm 1 (see FIG. 14 )) pressing the teeth of the gear is applied to the main gear, whereby the valve element 14 is moved toward the valve seat 13 in a lever-principle manner (see FIG. 15 ). Subsequently, when the driving voltage (current) for the motor 32 is gradually increased, the output shaft 32a and the motor gear 43 are rotated in a forward direction (i.e., a direction for opening the valve element 14), and this rotational speed is reduced by the intermediate gear 42 and transmitted to the main gear 41. Consequently, the valve element 14 is opened against the return spring force Fs 1 applied by the return spring 40 and urging the valve element 14 in a closing direction of the valve, so that the passage 11 is opened (see FIGS. 16 and 18 ). When the drive voltage supplied to the motor 32 is thereafter maintained at a constant level in the opening operation of the valve element 14, the motor drive force Fm 1 and the return spring force Fs 1 conform to an opening degree of the valve element 14 at this time, so that the valve element 14 is maintained at a predetermined opening degree.Further details of the operation of the integrated valve 181 of the present embodiment will be described below. During non-operation of the motor 32 that is not activated (i.e., because the motor 32 is stopped), the valve opening angle θ is "0", that is, the integrated valve 181 is in the valve closed position. At this time, as shown in FIG. 11, the full close stopper portion 41a of the main transmission 41 is in contact with the close position stopper portion 35b of the valve housing 35.In this connection, the ratio of forces in a circumferential direction of the rotatable shaft 15 or around the rotatable shaft 15 is considered as follows. As shown in FIG. 12, the spring hook part 41 cof the main transmission 41 receives the spring restoring force Fs 1 from the near-side hook 40 bof the restoring spring 40. In a rectangular or Cartesian coordinate system, as in FIG. 12, consisting of an origin represented by the central axis Ls of the rotatable shaft 15, an x-axis represented by a horizontal line, and a y-axis represented by a vertical line, a first quadrant is a portion defined by a positive x-axis and a positive y-axis, a second quadrant is a portion defined by a negative x-axis and a positive y-axis, a third quadrant is a portion defined by a negative x-axis and a negative y-axis, and a fourth quadrant is a portion defined by a positive x-axis and a negative y-axis. At this time, the far-side hook 40 aand the full-closing stopper portion 41 aare located at a position corresponding to the first quadrant, and the near-side hook 40 band the spring hook part 41 care located at a position corresponding to the third quadrant.Here, according to the principle of lever, a fulcrum is set in the full closing stopper portion 41a, a center of gravity (point of effort) is set in the spring hook part 41c, and a force application point is set in a middle portion between the full closing stopper portion 41a and the spring hook part 41c. Thus, the spring restoring force Fs 1 applied to the spring hook part 41 causes a force Fs 2 acting on the central portion between the full closing stopper portion 41 aand the spring hook part 41 c. This is expressed by: "force Fs2"=2 x "spring return force Fs1". In FIG. 12, the distance between the full closing stopper portion 41 aand the spring hook part 41 cis set to "2R".At this time, the ratio of forces in terms of a cross section of the rotatable shaft 15 along the central axis Ls is considered as follows. A +y direction component of the force Fs 2 is a force component Fs 3 as in FIG. 13. the +y direction set a direction perpendicular to a direction of a central axis Lj of the first bearing 37 and the second bearing 38 (the x direction) and a direction in which the valve seat 13 is disposed relative to the valve element 14 (an upward direction in the drawing sheet of FIGS. 12 and 13 ). This is expressed by: "force component Fs3"="force Fs2"x"sin θ1". The angle θ 1 is an angle that is disposed between the arrangement direction in the full closing stopper portion 41 aand the spring hook part 41 cand the x direction as illustrated in FIG. 12.The force component Fs 3 causes a force Fs 4 (a force urging in a separating direction) acting on the spring guide portion 41 din the +y direction. This is expressed by: "Force Fs4"="Force component Fs3"x Lb / La. Thereby, the force Fs 4 is a force caused by the spring return force Fs 1 and acts in a direction perpendicular to the central axis Lj of the first bearing 37 and the second bearing 38. The distance La is a distance from the location where the first bearing 37 is disposed to a location where the force Fs 4 acts in the x direction. The distance Lb is a distance from the location where the first bearing 37 is disposed to a location where the force Fs 3 acts in the x direction.When the force Fs 4 acts in the +y direction at the location of the spring guide portion 41 d, the rotatable shaft 15 assembled with the spring guide portion 41 dis rotated and inclines clockwise in FIG. 13 about the first bearing 37 serving as a fulcrum. According to the principle of lever, the main gear 41 provided at the proximal end 15 bof the rotatable shaft moves in the +y direction while the valve element 14 provided at the pin 15 aof the rotatable shaft 15 is moved in the -y direction. Thus, the valve element 14 is moved in a direction away from the valve seat 13 (a separating direction). In the above-described manner, during the time when the motor 32 is not operated and the integrated valve 181 is in a valve closed position, the valve element 14 is moved by a force Fs 4 in a direction to separate from the valve seat 13. At this time, the rotatable shaft 15 is stopped by the second bearing 38.In the present embodiment, at this time, the valve element 14 is in contact with the rubber seat 21 (a sealing member) provided in the valve seat 13, as shown in FIG. 13. More specifically, as shown in FIG. 21, the valve element 14 contacts the front end of a deformable portion 21 a(a bead portion) of the rubber seat 21, in which state the valve element 14 is in contact with the front end of the deformable portion 21 aover its entire circumference, and the deformable portion 21 ais only slightly deformed. Thereby, the integrated valve 181 can increase the sealing property with a simple structure because the rubber seat 21 seals between the valve seat 13 and the valve element 14. Here, the requirement of the integrated valve is a sealing function to prevent the suction of air into the fuel cell 111 during the stop of a vehicle in which the fuel cell system 101 is installed. In the present embodiment, the rubber seat 21 seals between the valve seat 13 and the valve element 14 for the required sealing function of the integrated valve 181.Moreover, at this time, the valve element 14 is located at a position represented by a point P 1 ain FIG. 20 which represents the relationship between the valve opening degree θ and the open area S. Here, the time "when the integrated valve 181 is in a valve closed position" corresponds to the time when the valve opening degree (the opening degree of the valve element 14) is "0", that is, the time when the rotation angle of the rotatable shaft 15 is an angle during the full closing (the smallest angle within the rotation range of the rotatable shaft 15).Thereafter, during the operation of the motor 32, namely, when the motor 32 is turned on, the motor driving force Fm 1 acts from the small-diameter gear 42 b(see FIG. 11 ) of the intermediate gear 42 on the gear portion 41 b(see FIG. 11 ) to rotate the main gear 41. with respect to the force ratio in a direction of a circumferential direction of the rotatable shaft 15 at this time, the motor driving force Fm 1 acts in the -y direction as illustrated in FIG. 14. This -y direction is a direction perpendicular to the direction of the central axis Lj (the x direction) of the first bearing 37 and the second bearing 38, and corresponds to a direction in which the valve element 14 is disposed relative to the valve seat 13 (a downward direction in the drawing sheets of FIGS. 12 and 13 ).The motor driving force Fm 1 causes a force Fm 2 acting in the -y direction at a position of the central axis Ls of the rotatable shaft 15. In addition, as for the force ratio in terms of the cross section of the rotatable shaft 15 along the central axis Ls, a force Fm 3 (seat direction urging force) acts in the negative y direction at a position of the spring guide portion 41 d, as shown in FIG. 15. This is expressed by: "Force Fm3"="Force Fm2"x Lb / La. During operation of the motor 32 in the above-described manner, the force Fm 3 is generated. This force Fm 3 is a force caused by the motor driving force Fm 1 and acting in a direction perpendicular to the central axis Lj of the first bearing 37 and the second bearing 38. The force Fm3 causes the rotatable shaft 15 to rotate and incline about the first bearing 37 serving as a fulcrum, thereby urging the valve element 14 toward the valve seat 13.As shown in FIG. 15, when the force Fm 3 becomes larger than the force Fs 4, the rotatable shaft 15 assembled with the spring guide portion 41 dof the main gear 41 is rotated and inclines counterclockwise in FIG. 14 about the first bearing 37 serving as the fulcrum. Thus, the valve element 14 is moved toward the valve seat 13 (a seating direction) by the force Fm 3.In the present embodiment, at this time, the deformable portion 21 aof the rubber seat 21 is compressed and deformed by the valve element 14. A deformation of the deformable portion 21a is smaller than in the case of a spatial deformation of the deformable portion 21a. Thus, the deformable portion 21a is elastically, but not plastically, deformed.The valve element 14 at this time is located at a position represented by a point P1b in FIG. 20 which represents the relationship between the valve opening degree θ and the open area S.Subsequently, when the driving voltage for the motor 32 increases and thus the motor driving force Fm 1 becomes large, the rotatable shaft 15 is further rotated and inclines further counterclockwise in FIG. 16 about the first bearing 37 serving as the fulcrum. At this time, the rotatable shaft 15 is rotated about the central axis Ls, so that the valve opening angle θ (the rotation angle of the rotatable shaft 15) becomes "α" (see FIG. 17 ) and the open area S increases. In this state, the full closing stopper portion 41a of the main transmission 41 separates from the closing position stopper portion 35b of the valve housing 35 as shown in FIG. 17. The rotatable shaft 15 is stopped by the second bearing 38 as shown in FIG. 16. The valve element 14 at this time is located at a position represented by a point P1c in FIG. 20 which represents the relationship between the valve opening degree θ and the open area S.Further, as the motor driving force Fm 1 continues to increase, the rotatable shaft 15 is further rotated about the central axis Ls. This causes the valve element 14 to separate from the valve seat 13, as shown in FIG. 18, thereby further enlarging the open area S. At this time, the valve opening degree θ becomes "β" (see FIG. 19 ). The valve element 14 at this time is in a position represented by a point P1d in FIG. 20 representing the relationship between the valve opening degree θ and the open area S. In the above-described manner, the valve opening operation of the integrated valve 181 is performed by the motor driving force Fm 1.In the present embodiment, the integrated valve 181 includes the two first and second bearings 37 and 38.As a conceivable modified example, a rubber seat 21 is used as shown in FIG. 22 or FIG. 23, the rubber seat 21 has a lip seal configuration in which the deformable portion 21 ais in a lip-like shape (a protruding shape that can be bent when pressed by the valve member 14). On the other hand, as shown in FIG. 23, the rubber seat 21 has a combined configuration of a lip seal and a bead in which the deformable portion 21 ais lip-like in shape and formed with a bead (a protrusion that can come into close contact with the valve element 14). The rubber seat may be provided in the valve element 14 instead of in the valve seat 13.In the present embodiment, the integrated valve 181 configured as above generates the force Fs 4 during non-operation of the motor 32. this force Fs 4 is a force that is caused by the spring restoring force Fs 1 and that acts in a direction perpendicular to the central axis Lj of the first bearing 37 and the second bearing 38. The force Fs4 causes the rotatable shaft 15 to incline about the first bearing 37 serving as the fulcrum, thereby urging the valve element 14 in the direction away from the valve seat 13. In addition, the rubber seat 21 is provided in either the valve element 14 or the valve seat 13 to seal between the valve element 14 and the valve seat 13 during non-operation of the motor 32.In the above manner, the rubber seat 21 closes or seals between the valve seat 13 and the valve element 14, and thus the integrated valve 181 can achieve an enhanced sealing property with a simple structure.In addition, in the present embodiment, rubber seat 21 includes a deformable portion 21 awith a front end that can come into contact with valve element 14 during non-operation of motor 32 and can be deformed when compressed by valve element 14 during operation of motor 32. Deformation of the deformable portion 21a during operation of the motor 32 is smaller than a plastic deformation of the deformable portion 21a. Accordingly, the deformable portion 21 aof the rubber seat 21 is not excessively compressed by the valve element 14, and thus abrasion of the rubber seat 21 can be reduced. In the case where the rubber seat 21 is provided in the valve element 14, the front end of the deformable portion 21 acontacts the valve seat 13 during non-operation of the motor 32 and is pressed and deformed against the valve seat 13 during operation of the motor 21.The eccentric valve according to the present invention is also applicable to seal the valve 174 and the bypass valve 191 in the air system 113 of the fuel cell system 101.[Second Embodiment]Next, a second embodiment will be described in which similar or identical components or parts to those of the first embodiment are assigned the same reference numerals as those of the first embodiment without repeating their explanation. The following description is directed to the difference from the first embodiment.In the present embodiment, after the power generation in the fuel cell 111 is stopped, the integrated valve 181 is closed, but the motor 32 is not immediately stopped. The motor 32 is further operated to press the valve element 14 against the rubber seat 21 for sealing between the valve element 14 and the rubber seat, and then the motor 32 is stopped to maintain the sealing.To this end, the controller 201 performs control based on the flowchart shown in FIG. 26 (fuel cell air integrated valve control). The controller first determines whether there is a fuel cell stack power generation stop request (step S 1). Here, a "fuel cell stack power generation stop request" is a request to stop power generation in the fuel cell 111. When the fuel cell stack power generation stop request is present (step S 1: YES), the controller 201 reads a stack pressure STP (step S 2), performs control for closing the sealing valve (step S 3), and rotates the sealing valve 174 to an OFF position, that is, stops or stops energization of the drive mechanism of the sealing valve 174 (step S 4) to perform the control for closing the integrated valve (step S 5). Here, the "stack pressure STP" is an internal pressure of the fuel cell 111. The "seal valve closing control" is a control for closing the seal valve 174. The "integrated valve closing control" is a control for closing the integrated valve 181.Subsequently, the controller 201 determines whether the stack pressure STP is equal to or less than a predetermined pressure a (a predetermined negative pressure) (step S 6). When the stack pressure STP is equal to or less than the predetermined pressure a (step S 6; YES), the controller 201 turns off energization of the motor 32 of the integrated valve 181, thereby switching the motor 32 from an operation state to a non-operation state (step S 7) and turns off energization of the ECU (ECU for sealing function control) (step S 8). Here, the predetermined pressure a is a negative pressure, i.e., lower than the atmospheric pressure.When the stack pressure STP decreases to be equal to or less than the predetermined pressure a, the controller 201 stops energization of the motor 32 of the integrated valve 181 to switch the motor 32 from an operating state to a non-operating state. Specifically, the engine is switched from an operating state to a non-operating state as follows. First, the excitation of the motor 32 while the internal pressure of the fuel cell 111 is higher than a predetermined pressure a is maintained to press the valve element 14 against the rubber seat 21 to provide a sealing state therebetween. Then, when the internal pressure of the fuel cell 111 becomes equal to or less than the predetermined pressure a, energization of the motor 32 is stopped so that the valve element 14 can contact the rubber seat 21 under the internal negative pressure of the fuel cell to form a sealing state between the valve element 14 and the rubber seat 21.In step S 6, when the stack pressure STP is higher than a predetermined pressure a (step S 6: NO), energization of the integrated valve 181 remains turned on, that is, the motor 32 of the integrated valve 181 continues to be energized and maintained in operation (step S 9), and energization of the ECU remains on (step S 10).In step S 1, when the fuel cell stack power generation stop request is not present (step S 1: YES), the controller performs control according to the power generation requests for the sealing valve 174, the integrated valve 181, and the bypass valve 191 (step S 11).When the control is executed based on the foregoing control flowchart, control is performed as in the control timing chart in Fig. 27. As shown in FIG. 27, energization of the motor 32 of the integrated valve 181 is stopped when the stack pressure STP becomes equal to or less than a predetermined pressure a at time T 2 after the fuel cell stack power generation stop request is made at time T 1.When the engine 32 according to the present embodiment is to be switched from an operating state to a non-operating state, the engine is switched to a non-operating state after the pressure on the valve element 14 on the side facing the valve seat 13, i.e., the stack pressure STP, reaches a predetermined pressure a. In this manner, the motor 32 is operated until the stack pressure STP reaches the predetermined pressure a, and after the stack pressure STP reaches the predetermined pressure a, the motor 32 is placed in a non-operating state that allows the valve element 14 to move toward the valve seat 13 by utilizing the negative pressure generated in the fuel cell 111. Even if the rubber seat 21 is worn, the sealing property or strength between the valve seat 13 and the valve element 14 during valve closing can be increased. In addition, during the interruption of power generation in the fuel cell 111, even when the motor 32 of the integrated valve 181 is switched to the non-operating state, the valve element can move toward the valve seat 13 by utilizing the negative pressure generated in the fuel cell 111. Thus, during non-operation of the engine 32, the sealing property between the valve seat 13 and the valve element 14 during valve closing can be increased.[Third Embodiment]Next, a third embodiment will be described below. Similar or identical components or parts to those of the first and second embodiments are assigned the same reference numerals as in these embodiments without repeating their explanation. The following description is directed to the difference of the first and second embodiments.In the present embodiment, during operation of the motor 32, control is executed in a seal control mode and a pressure regulation mode. Here, the seal control mode is a mode for controlling the rotation of the valve element 14 during an opening degree of the valve element 14 near a fully closed position. This sealing mode is executed, for example, during a stop of the vehicle in which the fuel cell system 101 is installed. The pressure regulation mode is a mode for controlling the open area S of the valve port 16 to regulate the flow rate of the air. In this pressure regulating mode, the opening degree of the valve element is controlled at an opening degree larger than that in the seal control mode. The pressure control mode is executed, for example, while the vehicle in which the fuel cell system 101 is mounted is running.For this, the controller 201 performs driving based on the control flowchart shown in FIG. 28 (fuel cell air integrated valve control). First, the controller 201 takes a stack air supply target amount (a target amount of air to be supplied to the fuel cell stack) TSTGa (step S 101), and controls a blowing amount of the air pump 172 up to an amount corresponding to the stack air supply target amount TSTGa (step S 102). The controller 201 further acquires a stack pressure STP (step S 103) and acquires a current integrated valve opening degree ata, that is, the current integrated valve valve opening degree of the valve element 14 (step S 104).Subsequently, the controller 201 determines whether or not there is a pressure regulation request for the integrated valve (step S 105). When the pressure regulation request for the integrated valve is present (step S 105: YES), it is determined whether or not an XACC flag is "0" (step S 106). The XACC flag is an angle A determination indicator.When the XACC flag is "0" (step S 106: YES), the controller 201 judges whether the current integrated valve opening degree ata is equal to or less than the angle A (step S 107). Here, the time when the actual integrated valve opening degree ata is the angle A corresponds to the time when the opening degree of the valve element 14 of the integrated valve 181, that is, the valve opening degree θ (the rotation angle of the rotatable shaft 15 and the rotation angle of the main transmission 41) is the angle A, as illustrated in FIG. 24. At this time, as shown in FIG. 24, the valve element 14 and the rubber seat 21 are not in contact with each other.When the actual integrated valve opening degree ata is equal to or greater than the angle A (step S 107: YES), that is, in the pressure regulating mode in which the valve element 14 and the rubber seat 21 are not in contact with each other, the XACC flag is switched to "1" (step S 108). Then, a target integrated valve opening degree tpcta and a target bypass valve opening degree tbta are determined to control a stack air supply amount STGa to the stack air supply target amount TSTGa. (Step S 109).The controller 201 then determines whether or not the integrated valve target opening degree tpcta is equal to or greater than the angle A (step S 110). When the target integrated valve opening degree tpcta is equal to or greater than the angle A (step S 110: YES), the controller 201 controls the opening degree of the valve element 114 of the integrated valve 181 to the target integrated valve opening degree tpcta with high responsiveness. Specifically, the controller 201 increases the rotational speed of the valve element 14 of the integrated valve 181 and adjusts the opening degree of the valve element 14 to the target integrated valve opening degree tpcta and controls the bypass valve 191 to the target high response bypass valve opening degree tbta (step S 111). The pressure regulating mode is thus executed when the valve element 14 and the rubber seat 21 are not in contact with each other.When the pressure regulation request for the integrated valve is not present in step S 105 (step S 105: NO), the controller 201 determines whether or not the XACC flag is "1" (step S 112). When the XACC flag is "1" (step S 112: YES), it is determined whether or not the current integrated valve opening degree ata is smaller than the angle A (step S 113). When the current integrated valve opening degree ata is smaller than the angle A (step S 113: YES), the controller 201 switches the XACC flag to "0" (step S 114), and controls that the integrated valve 181 is fully closed via an integrated valve slow closing drive (step S 115). Specifically, in the sealing control mode in which the actual integrated valve opening degree ata is smaller than the angle A (i.e., when the opening degree of the valve element 14 is near a fully closed position), the controller 201 causes the integrated valve 181 to be fully closed during a reduction in the rotational speed of the valve element 14. In this way, the rotational speed of the valve element 14 in the seal control mode is slower than the rotational speed of the valve element 14 in the pressure regulation mode.When the XACC flag is not "0" in step S 106 (STEP S 106: NO), the process in step S 109 is further executed.When the actual integrated valve opening degree ata is smaller than the angle A in step S 107 (step S 107: NO), the control for slowly opening the integrated valve is performed, that is, the valve opening control is performed by reducing the rotational speed of the valve element 14 (step S 116), and the process in step S 106 is performed. Specifically, in the sealing control mode in which the actual opening degree ata of the integrated valve is smaller than an angle A (i.e., when the opening degree of the valve element 14 is near a full closing position), the integrated valve 181 is opened during a reduction in the rotational speed of the valve element 14.When the target integrated valve opening degree tpcta is smaller than the angle A in step S 110 (step S 110: NO), the process of step S 111 is executed by assigning the target integrated valve opening degree tpcta to the angle A (step S 117).When the XACC flag is not "1" in step S 112 (step S 112: NO), the process in step S 115 is further executed.In step S 113, when the actual integrated valve opening degree ata is equal to or greater than the angle A (step S 113: NO), rapid closing control of the integrated valve, that is, valve closing control is performed by increasing the rotational speed of the valve element 14 (step S 118). As a result, the process in step S 112 is executed.When the control is executed based on the foregoing control flowchart, for example, control as shown in the control timing chart in FIG. 29 is performed. As shown in FIG. 29, slow seal change control is performed at a time T 11 and a time T 15. Specifically, the control for slowly opening the integrated valve is performed at time T 11 and the control for slowly closing the integrated valve is performed at time T 15. In addition, at time T 12 and time T 14, high-responsiveness pressure regulation control is executed. Specifically, the opening degree of the valve element 14 of the integrated valve 181 is controlled with high responsiveness. Further, at time T 11 and time T 14, high responsiveness bypass control, that is, the opening degree of the valve element of the high responsiveness bypass valve 191 is controlled.According to the present embodiment, the control mode to be executed during the operation of the engine 32 includes the pressure regulating mode and the seal control mode. In the pressure regulating mode, the valve element 14 and the rubber seat 21 are not in contact with each other. Since the valve element 14 and the rubber seat are not in contact with each other in the high frequency pressure regulating mode, the number of times the valve element 14 and the rubber seat slide on each other can be reduced, so that abrasion or wear of the rubber seat 21 can be reduced.The rotational speed of the valve element 14 in the seal control mode is slower than the rotational speed of the valve element in the pressure regulating mode. Accordingly, the sliding intensity of the valve element 14 with respect to the rubber seat 21 can be reduced in the seal control mode, thus enabling reduction in abrasion and wear of the rubber seat 21.[Fourth Embodiment]Next, a fourth embodiment will be described below in which similar or identical components or parts to those of the first to third embodiments are assigned the same reference numerals as those of the first to third embodiments without repeating their explanations. The following description is directed to the difference from the first to third embodiments.In the present embodiment, in a vehicle having the fuel cell system 101 mounted, when the regenerative brake is requested and the power generation of the fuel cell 111 is stopped, the surplus electric power generated in the fuel cell 111 by reaction between the hydrogen gas and the oxygen gas is consumed for driving the air pump 172 while a battery (not shown) is in a fully charged state. At this time, the integrated valve 181 is closed, but an air discharge amount of the integrated valve 181 does not need to be zero. Thus, in the presence of a regenerative brake braking request, the integrated valve 181 is not driven to fully close but is driven to bring the valve element 14 to a position where it starts to contact the rubber seat 21 (for example, a position as shown in FIG. 15 ) so that the valve element 14 is pressed against the rubber seat 21 with low pressure. Specifically, the opening degree of the valve element 14 is set to an angle B that is larger than the set full close angle and smaller than the angle A.To this end, the controller 201 performs control based on the control flowchart shown in FIG. 30 (fuel cell air control). When an ignition switch IG is turned "ON" (step S 201: YES), the controller 201 determines whether there is a power generation request (step S 202). When the power generation request is present (step S 202: YES), it is further determined whether the regenerative brake braking request is present (step S 203). When the regenerative brake braking request is present (step S 203: YES), the opening degree of the valve element 14 of the integrated valve 181 is set to the angle B (step S 204), the bypass valve 191 is driven to fully close (step S 205), the air pump 172 is driven to operate at a speed of a regenerative mode (step S 206), and an XEB flag is switched to "1" (step S 207).In this way, the opening degree of the valve element 14 is maintained at the angle B when the regenerative brake braking request is made and thus the air pump 172 is operated. This angle B is an opening degree at a point within the opening degree range in the seal control mode, and is larger than the full close set angle and smaller than the angle A. The XEB flag is a regenerative brake control flag which is set to "0" when the regenerative brake is not acting or which is set to 1 when the regenerative brake is operating.In step S 202, when there is no power generation request (step S 202: NO), the controller 201 stops the air pump 172 (step S 208), performs the control for fully closing the sealing valve, the integrated valve, and the bypass valve (steps S 209 to S 211), and switches the XEB flag to "0" (step S 212).When the regenerative brake braking request is not present (step S 202: NO), the control determines whether the XEB flag is 1 (step S 213) in step S 203. When the XEB flag is "1", that is, when there is a return request (step S 213: YES), the controller 201 promptly performs the full close drive of the bypass valve 191, the valve opening control, and the valve closing control (step S 214), switches the XEB flag to "0" (step S 215), and then, proceeds the process to step S 213.When the XEB flag is not "1" in step S 213, that is, when there is a current power generation request (a request for power generation during operation) (step S 213: NO), an output request is made (step S 216), and the full opening drive of the seal valve is executed (step S 217) to control the opening degree of the integrated valve, the opening degree of the bypass valve, and the number of rotations of the air pump according to the output request (step S 216).When the control according to the above control flowchart is executed, for example, control is performed as shown by a control timing chart in FIG. 31. As shown in FIG. 31, the regenerative control is performed at time T 25. Specifically, the opening degree of the valve element 14 of the integrated valve 181 is set to an angle B at time T 25.According to the present embodiment, the opening degree of the valve element 14 is maintained at the angle B when the air pump 172 is operated in response to a braking request of the regenerative brake. Thus, the control for fully closing the integrated valve 181 is not executed when the regenerative brake braking request is repeated, but only when a vehicle is fully stopped. This makes it possible to prevent the valve element 14 and the rubber seat 21 from sliding back and forth against each other. Thus, excessive electric power generated at the braking request of the regenerative brake will be consumed for the operation of the air pump 172 while inhibiting the wear of the rubber seat 21.The above embodiments are merely examples and do not limit the present invention. The present invention may be embodied in other specific forms without departing from the essential characteristics of this invention. For example, the rotatable shaft 15 may be supported at both ends by the first bearing 37 and another bearing (not shown) separately disposed on an opposite side of the valve element 14List of Reference Numerals2 Valve portion 3 Drive mechanism portion 11 Passage 13 Valve seat 14 Valve element 15 Rotatable shaft 15 aPin 15 b Proximal end portion 16 Valve hole 17 Seating surface 18 Sealing surface 21 Rubber seat 21 a Deformierbar portion 21 b Wulst 32 Motor 35 bLosure stopper portion 35 cSpring hook part 37 First bearing 38 Second bearing 40 Return spring 40 a Fern-side hook 40 b Nah-side hook 41 Main gear 41 a Stopper complete closing stopper portion 41 b Zahnrad portion 41 cSpring hook part 41 dSpring guide portion 101 Fuel cell system 111 Fuel cell 112 Hydrogen system 113 Air system 162 Air discharge line 174 Seal valve 181 Integrated valve 191 Bypass valve Ls Mittelachse axis (rotatable shaft) Lv Mittelachse axis (valve element) Lj Mittelachse axis (valve element) Bearing) Fs 1 Return spring force Fs 4 Force (in a separating direction urging force) Fm 1 Motor driving force Fm 3 Force (in the seating direction urging force) θ Valve opening degree

Claims

An eccentric valve (181) comprising: a valve seat (13) having a valve hole (16) and a seating surface (17) formed at an edge of the valve hole (16); a valve element (14) formed with a sealing surface (18) on an outer periphery corresponding to the seating surface (17); a rotatable shaft (15) installed with the valve element (14) for rotating the valve element (14), and the rotatable shaft (15) has a central axis extending parallel to a radial direction of the valve element (14), wherein the central axis of the rotatable shaft (15) is arranged eccentrically from a center of the valve opening (16) in another radial direction of the valve opening (16), and the sealing surface is arranged eccentrically from the central axis of the rotatable shaft (15) toward an extension direction of the central axis of the valve element (14), the eccentric valve further comprising: a drive mechanism for generating a drive force for rotating the rotatable shaft (15) in a direction for opening the valve; a drive force receiving part integrally installed with the rotatable shaft (15) for receiving the drive force; a bearing for supporting the rotatable shaft (15) disposed at a position between the valve element (14) and the driving force receiving part in a direction of the central axis of the rotatable shaft (15); and a return spring (40) for generating a return spring force (Fs1) to rotate the rotatable shaft (15) in a direction for closing the valve, wherein, during non-operation of the driving mechanism (32), the eccentric valve generates a separating direction urging force (Fs4) such that the rotatable shaft (15) inclines about the bearing (37) as a fulcrum and the valve element (14) is urged in a direction away from the valve seat (13), the separating direction urging force being a force, which is based on the restoring spring force (Fs1) and acts in a direction perpendicular to the central axis (Lj) of the bearing (37, 38), and either the valve element (14) or the valve seat (13) has a sealing member (21) to seal between the valve element (14) and the valve seat (13) during non-operation of the drive mechanism (32).The eccentric valve (181) according to claim 1, wherein the sealing member (21) includes a deformable portion (21a) having a front end which comes into contact with the valve element (14) or the valve seat (13) during non-operation of the driving mechanism (32) and which is deformed when compressed by the valve element (14) or a valve seat (13) during operation of the driving mechanism (32), and the deformation of the deformable portion (21a) during operation of the driving mechanism (32) is smaller than the deformation of the deformable portion (21a) during plastic deformation.The eccentric valve (181) according to claim 1 or 2, wherein when the driving mechanism (32) is to be switched from an operating state to a non-operating state, the driving mechanism is switched to the non-operating state after a pressure on the valve element (14) on a side facing the valve seat (13) reaches a predetermined negative pressure.The eccentric valve (181) according to any one of claims 1 to 3, wherein the eccentric valve is configured to execute a control mode during operation of the drive mechanism (32), the control mode comprising a pressure regulating mode for controlling an open area of the valve opening (16) and a seal control mode for controlling rotation of the valve element (14) near a fully closed position of the valve element (14).The eccentric valve (181) according to claim 4, wherein a rotational speed of the valve element (14) in the seal control mode is slower than a rotational speed of the valve element (14) in the pressure regulating mode.The eccentric valve (181) according to claim 4 or 5, wherein the valve element (14) and the sealing element (21) are not in contact with each other in the pressure regulating mode in the aforementioned configuration.The eccentric valve (181) according to any one of claims 4 to 6, wherein the eccentric valve has a passage through which air flows into a fuel cell system (101), and when the fuel cell system (101) drives an air pump (172) for controlling the flow rate of the air in response to a request for a regenerative brake, an opening degree (θ) of the valve element (14) is maintained at an opening degree within an opening degree range determined in the seal control mode.

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