JP2005189949A - Fuel cell power generation system and gas pressure reducing valve for the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a fuel battery power generation system and a gas pressure reducing valve for the fuel cell power generation system which is advantageous for adjusting the characteristics of the gas flow rate/pressure of gas containing active substances while increasing responsiveness. <P>SOLUTION: This fuel cell power generation system is provided with a gas pressure reducing valve 1, and the gas pressure reducing valve 1 is provided with a body 2 having a diaphragm chamber 20, a deformable diaphragm 3 for dividing the diaphragm chamber 20 into a first chamber 21 and a second chamber 22, a primary side passage 6 to which gas containing the active materials is supplied, a secondary side passage 71 connected through the first chamber 21 to the fuel cell, a diaphragm opening degree varying mechanism 4 installed between the primary side passage 6 and the secondary side passage 71 for supplying gas through the first chamber 21 to the secondary side passage 71 by reducing the gas flow rate of the primary side passage 6, an elastic member 7 for energizing the diaphragm 3 to a direction where the diaphragm opening degree of the diaphragm opening degree varying mechanism 4 is increased or decreased and an actuator 9 for adjusting the energizing force of the elastic member 7. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a fuel cell power generation system having a gas pressure reducing valve for a fuel cell power generation system for reducing the pressure of a fuel gas or an oxidant gas sent to a primary passage and supplying the pressure to a fuel electrode or an oxidant electrode of a fuel cell. The present invention also relates to a gas pressure reducing valve for a fuel cell power generation system.

  Conventionally, as a gas valve, a body having a diaphragm chamber, a deformable diaphragm that divides the diaphragm chamber of the body into a first chamber and a second chamber, and a high-pressure passage that is a primary-side passage to which gas is supplied, A throttle opening variable mechanism that has a low pressure passage that is a secondary side passage, a throttle hole provided between the high pressure passage and the low pressure passage, and that adjusts a throttle opening of the throttle hole; There has been known one provided with a coil spring that exerts an urging force for urging the diaphragm in the direction of increasing the opening (Patent Document 1). It is described that this gas valve can also be used for a gas flow path for a fuel cell. According to this gas valve, the gas in the high-pressure passage is restricted by the restriction hole and reaches the low-pressure passage. When the pressure in the low pressure passage increases, the diaphragm is deformed in a direction to decrease the throttle opening of the throttle hole, and an increase in the pressure in the low pressure passage is suppressed.

In addition, conventionally, as a pressure reducing valve having a diaphragm and a pressure setting spring for urging the diaphragm as an automatic setting pressure reducing valve, a motor for adjusting the elastic force of the pressure setting spring is attached, and the elasticity of the pressure setting spring is driven by driving the motor. What adjusts force is known (patent document 2). Note that this automatically set pressure reducing valve is not described for fuel cell power generation. According to this, the pressure of the high pressure passage which is the primary passage acts on the upper surface of the piston through the pilot valve body. Here, when the diaphragm is displaced downward, the pilot valve body is pushed down, the piston that is the main valve body is pushed down, and the throttle opening of the valve port increases. When the diaphragm is displaced upward, the pilot valve body is pushed up, the piston that is the main valve body is pushed up, and the throttle opening of the main valve port decreases.
JP 2002-372162 A JP 63-20603 A

  According to the gas valve according to Patent Document 1 described above, since the spring force of the coil spring that biases the diaphragm is fixed, the gas flow rate-pressure characteristics in the low-pressure passage that is the secondary passage are adjusted. There is a limit.

  Moreover, according to the automatic setting pressure reducing valve according to Patent Document 2 described above, since the pilot valve body is used, there is a limit in improving the responsiveness with respect to the throttle opening degree of the valve port.

  The present invention has been made in view of the above circumstances, and is a fuel that is advantageous for adjusting the characteristics of the gas flow rate-pressure in the secondary passage of the gas containing the active material supplied to the fuel cell while improving the response. It is an object of the present invention to provide a battery power generation system and a gas pressure reducing valve for a fuel cell power generation system.

A fuel cell power generation system according to a first aspect includes a fuel cell having a fuel electrode and an oxidant electrode, a gas supply passage for fuel that supplies fuel gas to the fuel electrode of the fuel cell, and an oxidant electrode that oxidizes the fuel cell. For a fuel cell power generation system provided upstream of a fuel cell in at least one of a gas supply passage for oxidant gas for supplying an oxidant gas, a gas supply passage for fuel, and a gas supply passage for oxidant gas In the fuel cell power generation system including the gas pressure reducing valve, the gas pressure reducing valve for the fuel cell power generation system is:
A diaphragm chamber; a deformable diaphragm that divides the diaphragm chamber into a first chamber and a second chamber; a primary passage to which a gas containing an active material used in a fuel cell is supplied; and a first chamber. The secondary side passage connected to the fuel electrode or the oxidant electrode of the fuel cell and the primary side passage are throttled by reducing the gas flow rate of the primary side passage. An aperture opening variable mechanism that supplies the secondary passage through the first chamber, an elastic member that exerts an urging force that biases the diaphragm in a direction to increase or decrease the aperture opening of the aperture opening variable mechanism, and elasticity And an actuator for adjusting the biasing force of the member.

  A gas pressure reducing valve for a fuel cell power generation system according to a second aspect is a gas pressure reducing valve used in a fuel cell power generation system connected to a fuel electrode or an oxidant electrode of a fuel cell, and includes a diaphragm chamber and a diaphragm chamber as a first one. A deformable diaphragm partitioned into a chamber and a second chamber, a primary passage to which a gas containing an active material used in the fuel cell is supplied, and a fuel electrode or an oxidant of the fuel cell through the first chamber A secondary passage that is connected to the pole, and is provided between the primary passage and the secondary passage, and the gas flow in the primary passage is reduced to allow the gas in the primary passage to pass through the first chamber. A throttle opening varying mechanism that supplies the diaphragm, an elastic member that exerts a biasing force that biases the diaphragm in a direction that increases or decreases the throttle opening of the throttle opening varying mechanism, and an actuator that adjusts the biasing force of the elastic member; Also characterized by comprising It is.

  According to the first aspect and the second aspect, the gas flow rate of the gas in the primary passage is throttled by the throttle opening of the throttle opening variable mechanism. Therefore, the secondary pressure of the gas in the secondary passage is reduced more than the primary pressure of the gas in the primary passage. Here, if the magnitude of the urging force by the elastic member is adjusted, the throttle opening of the variable throttle opening mechanism can be adjusted to increase or decrease. Therefore, if the urging force of the elastic member is adjusted by operating the actuator, the urging force for urging the diaphragm can be adjusted, so that the throttle opening of the variable aperture opening mechanism can be adjusted to increase or decrease. . This is advantageous in adjusting the gas flow rate-pressure characteristics of the gas containing the active material in the secondary passage connected to the fuel cell. Examples of the elastic member include a spring such as a coil spring and a plate spring, an organic material such as rubber and resin, a foam material, and a gas spring such as an air spring.

  The gas pressure reducing valve for the fuel cell power generation system according to the third aspect is characterized in that a driving force transmission mechanism is provided between the actuator and the diaphragm. In this case, the driving force of the actuator can be satisfactorily transmitted to the diaphragm by the driving force transmission mechanism. An example of the driving force transmission mechanism is a piston-like movable body.

  According to the gas pressure reducing valve for the fuel cell power generation system according to the fourth aspect, the actuator is a motor or a solenoid. The motor may be a rotating type or a direct acting type. Examples of the motor include a direct current motor, an alternating current motor, and an ultrasonic motor. The solenoid can be exemplified by a type driven based on a magnetic attractive force or a magnetic repulsive force.

  According to the gas pressure reducing valve for the fuel cell power generation system according to the fifth aspect, the throttle opening variable mechanism includes a throttle hole provided between the primary side passage and the secondary side passage, a valve chamber, and a valve. A movable valve provided in the chamber and facing the throttle hole, and a movable valve biasing member that biases the movable valve in a direction to close the throttle hole are provided. Examples of the urging member for the valve include a spring such as a coil spring and a leaf spring, an organic material such as rubber and resin, a foam material, and a gas spring such as an air spring.

  According to the present invention, the urging force of the elastic member can be adjusted by operating the actuator, and accordingly, the throttle opening of the variable throttle opening varying mechanism can be adjusted to increase or decrease. This is advantageous in setting the gas flow rate-pressure characteristics of the gas containing the active material supplied to the fuel cell to a plurality of forms. Furthermore, it is the actuator that adjusts the urging force of the elastic member, and the responsiveness can be improved since the pilot valve is not used for opening and closing the throttle hole.

(Embodiment 1)
Embodiment 1 according to the present invention will be described in detail with reference to FIGS. The gas pressure reducing valve 1 for the fuel cell power generation system according to the present embodiment is provided on the upstream side of the gas inlet 101 c of the fuel electrode 101 of the fuel cell 100. As shown in FIG. 1, the gas pressure reducing valve 1 includes a body 2 having a diaphragm chamber 20 and a valve chamber 23 partitioned by a wall portion below the diaphragm chamber 20, and the diaphragm chamber 20 of the body 2 as a first chamber. Deformable diaphragm 3 partitioned into 21 and second chamber 22, and high-pressure passage 61 which is a primary-side passage to which a gas (fuel gas) containing an active material used in fuel electrode 101 of fuel cell 100 is supplied. The diaphragm 3 has a low pressure passage 71 which is a secondary side passage connected to the fuel electrode 101 of the fuel electrode 101 of the fuel cell 100 and a throttle hole 40 provided between the high pressure passage 61 and the low pressure passage 71. Along with this, there is provided a throttle opening variable mechanism 4 that makes the throttle opening L of the throttle hole 40 variable.

  The high-pressure passage 61 is connected to a gas supply source 65 (for example, a gas tank). The high-pressure fuel gas from the gas supply source 65 is supplied to the high-pressure passage 61. As the fuel gas, pure hydrogen gas or hydrogen-containing gas can be used. The low pressure passage 71 is connected to the fuel electrode 101 of the fuel cell 100. Here, the high pressure and the low pressure mean the relative height of the fuel gas. Therefore, high pressure means higher pressure than the gas pressure in the low pressure passage 71. Low pressure means a pressure lower than the gas pressure in the high pressure passage 61. For example, the pressure PH of the gas in the high pressure passage 61 can be set to 1 to 3 MPa, and the pressure PL of the gas in the low pressure passage 71 can be set to 10 to 900 kPa and 100 to 400 kPa. However, it is not limited to these.

  The high pressure passage 61 is provided upstream of the throttle hole 40, and the low pressure passage 71 is provided downstream of the throttle hole 40. The throttle hole 40 limits the flow rate of the gas (fuel gas) in the high-pressure passage 61 containing the active material used in the fuel electrode 101 of the fuel cell 100 to reduce the pressure, and supplies it to the low-pressure passage 71.

  As shown in FIG. 1, the body 2 has a diaphragm chamber 20. The diaphragm 3 is formed in a film shape using an elastic material such as rubber or soft resin, or a metal as a base material, and the diaphragm chamber 20 of the body 2 has a first chamber 21 into which a fuel gas containing an active material flows, a fuel It partitions and divides into the 2nd chamber 22 into which gas does not flow in. The second chamber 22 communicates with the atmosphere via the atmosphere opening port 22m. Since the second chamber 22 is thus opened to the atmosphere, it does not enter a high pressure state.

  The outer peripheral portion 3p of the diaphragm 3 is held between the body 2 and held. The central area of the diaphragm 3 can be deformed in an arrow Y2 (upward direction) and an arrow Y1 direction (downward direction) according to the differential pressure between the first chamber 21 and the second chamber 22. The arrow Y2 direction means a direction in which the volume of the first chamber 21 is increased and a direction in which the throttle opening L of the throttle hole 40 is decreased. The arrow Y1 direction means a direction in which the volume of the first chamber 21 is decreased and a direction in which the throttle opening L of the throttle hole 40 is increased. As can be understood from FIG. 1, the pressure in the first chamber 21 (connected to the fuel cell 100 via the low pressure passage 71) located downstream of the throttle hole 40 acts on the surface 3 m as the lower surface of the diaphragm 3.

  As shown in FIG. 1, the throttle opening varying mechanism 4 includes a throttle hole 40 formed in the body 2 so as to limit the flow rate of a gas (fuel gas) containing an active material supplied to the fuel cell 100, and a throttle. It has a piston-like movable valve 41 that opens and closes the hole 40, and a first support portion 42 and a second support portion 43 that are provided so as to sandwich the central region of the diaphragm 3. The movable valve 41 has a pressure receiving surface 47 and a valve surface 44 that face each other. According to this embodiment, the pressure receiving surface 47 is the illustrated lower surface of the movable valve 41. The valve surface 44 is the upper surface of the movable valve 41 in the figure.

  The throttle hole 40 has a ring-shaped valve seat portion 49 that goes around the throttle hole 40 on one side, that is, the lower side. The shaft portion 48 of the second support portion 43 extends downward so as to move away from the second support portion 43, and is inserted through the throttle hole 40.

  The distal end portion (lower end portion) of the shaft portion 48 of the second support portion 43 comes into contact with the valve surface 44 of the movable valve 41 by the biasing force of the diaphragm spring 7 and the valve spring 8 described later. Here, a throttle opening L of the throttle hole 40 is set between the valve seat portion 49 and the valve surface 44 of the movable valve 41. Although the gap width of the throttle opening L is emphasized in FIG. 1, it is actually small. The valve surface 44 of the movable valve 41 faces the valve seat portion 49 so that it can be seated on the valve seat portion 49 of the throttle hole 40 when the throttle hole 40 is fully closed.

  As shown in FIG. 1, a movable valve 41 is fitted in the valve chamber 23 of the body 2 so as to be movable in the directions of arrows Y2 and Y1 (vertical direction). The movable valve 41 is disposed below the diaphragm 3 in the drawing, and the cross section of the movable valve 41 is a circular cylinder, but it may be a prism. Here, the diameter of the valve chamber 23 and the diameter of the movable valve 41 are set smaller than the diameter of the movable deformation portion of the diaphragm 3. The movable valve 41 is made of metal and substantially functions as a rigid body. The pressure receiving surface 47 of the movable valve 41 faces the wall surface 2 f of the body 2, and the valve surface 44 of the movable valve 41 faces the throttle hole 40.

  As shown in FIG. 1, in the second chamber 22 of the diaphragm chamber 20 of the body 2, a diaphragm spring 7 (elastic member) that can function as a biasing member formed of a coil spring is provided substantially coaxially. Yes. One end portion 7a of the diaphragm spring 7 is seated on the seating surface 42h of the first support portion 42 of the aperture opening varying mechanism 4, and the other end portion 7b of the diaphragm spring 7 is a ring-shaped seating surface 92h of the movable body 92 described later. Sit on. As a result, the diaphragm spring 7 urges the diaphragm 3 in the arrow Y1 direction (the downward direction in the figure), and thus urges the movable valve 41 away from the valve seat portion 49. That is, the diaphragm spring 7 urges the movable valve 41 in the direction in which the throttle opening L of the throttle hole 40 is increased.

  As shown in FIG. 1, between the movable valve 41 and the wall surface 2f of the body 2, the valve spring 8 which functions as an urging member for the movable valve formed of a coil spring is provided. The movable valve 41 is urged in the direction of the arrow Y2 by the valve spring 8, that is, urged in a direction in which the valve surface 44 of the movable valve 41 approaches the valve seat portion 49. That is, the valve spring 8 biases the movable valve 41 in a direction that decreases the throttle opening L of the throttle hole 40.

  The valve spring 8 and the diaphragm spring 7 exhibit urging forces that are opposite to each other. For this reason, the contact property between the valve surface 44 of the movable valve 41 and the distal end portion 48 a of the shaft portion 48 of the second support portion 43 is ensured. According to this embodiment, the spring load of the diaphragm spring 7 is set larger than the spring load of the valve spring 8. This is to keep the throttle hole 40 open when no gas is introduced.

  According to this embodiment, the body 9 is provided with the actuator 9 that adjusts the urging force of the diaphragm spring 7. The actuator 9 is a motor (for example, a DC motor), and has an actuator main body 90 and a rotatable drive shaft 91 protruding from the actuator main body 90. A male screw portion 91 c is formed on the outer peripheral portion of the drive shaft 91. A piston-like movable body 92 as a driving force transmission mechanism is provided between the actuator 9 and the diaphragm 3, that is, between the actuator 9 and the diaphragm spring 7. The movable body 92 has a large-diameter portion 92a having a seating surface 92h and a small-diameter portion 92c integrated with the large-diameter portion 92a.

  As shown in FIG. 2, an engaging portion 92m that engages with the engaged portion 2m of the body 2 is provided on the outer wall of the movable body 92, and the movable body 92 is in the directions of arrows Y1 and Y2 shown in FIG. Although it can move linearly (opening direction and closing direction of the throttle hole 40), it is set so that it cannot rotate in the circumferential direction (arrow R1 direction, R2 direction shown in FIG. 2) of the movable body 92. A female screw portion 93 c is formed on the inner peripheral portion of the hole 93 formed in the central region of the small diameter portion 92 c of the movable body 92. The female screw portion 93c and the male screw portion 91c are screwed together so as to be able to advance and retreat, and can function as a conversion mechanism that converts rotational motion into linear motion.

  When the actuator 9 is driven in one direction and the drive shaft 91 is rotated in one direction around the shaft core 91p, the movable body 92 moves in the direction of the arrow Y1 (the opening direction of the aperture hole 40). The length KA is reduced, and the urging force of the diaphragm spring 7 is increased. When the actuator 9 is driven in the other direction and the drive shaft 91 rotates in the other direction around its axis 91p, the movable body 92 moves in the direction of the arrow Y2 (the closing direction of the aperture hole 40), and the diaphragm spring The length KA of 7 is expanded, and the urging force of the diaphragm spring 7 is reduced.

  When the gas pressure reducing valve 1 according to this embodiment is used, a relatively high pressure fuel gas is supplied to the high pressure passage 61 from a gas supply source 65 loaded with a high pressure fuel gas. The flow rate of the high-pressure gas is limited by the throttle opening L of the throttle hole 40. For this reason, the pressure in the first chamber 21 located downstream of the throttle hole 40 is reduced more than the pressure in the high-pressure passage 61. The gas that has been reduced in pressure by the throttle opening L of the throttle hole 40 and reduced to the set pressure passes through the first chamber 21, reaches the low pressure passage 71 via the port 2 k, and further enters the fuel electrode 101 of the fuel cell 100. Supplied and used for power generation reaction.

  Based on the pressure difference between the pressure in the first chamber 21 and the pressure in the second chamber 22 decompressed by the throttle hole 40, the force applied to the diaphragm 3 in the arrow Y2 direction (upward, the closing direction of the throttle hole 40) is F1. And Further, the force by which the valve spring 8 urges the movable valve 41 in the arrow Y2 direction (upward, the closing direction of the throttle hole 40) is defined as F2. A force F3 (assumed to be upward) is a difference between the downward pressure of the valve surface 44 of the movable valve 41 in the direction of the arrow Y1 and the pressure of the pressure receiving surface 47 of the movable valve 41 received by the gas pressure of the valve chamber 23 upward. And Further, the diaphragm spring 7 moves the movable valve 41 in the direction of the arrow Y1 through the diaphragm 3, the first support portion 42, and the second support portion 43 by the spring load (biasing force) thereof (downward, opening the throttle hole 40). The force urging in the direction is F4.

  Basically, the position of the movable valve 41 is maintained when the sum of the upward force F1 + force F2 + force F3 in the direction of the arrow Y2 and the downward force F4 in the direction of the arrow Y1 are balanced. This balance basically determines the throttle opening L of the throttle hole 40. When the sum of the upward force F1 + force F2 + force F3 in the direction of the arrow Y2 and the magnitude of the downward force F4 in the direction of the arrow Y1 change, the position where the movable valve 4 is balanced changes. The degree L changes.

  Here, if the driving amount of the actuator 9 is adjusted, the moving position of the movable body 92 in the directions of the arrows Y1 and Y2 can be adjusted, so that the biasing force of the diaphragm spring 7 is increased or decreased. be able to. Thus, the force F4 for urging the movable valve 41 in the direction of the arrow Y1 (downward, opening direction of the throttle hole 40) via the diaphragm 3, the first support portion 42, and the second support portion 43 can be adjusted. The throttle opening L of the throttle hole 40 is adjusted accordingly.

  Here, FIG. 3 shows the relationship between the gas flow rate in the low pressure passage 71 and the secondary pressure P2 in the low pressure passage 71. A characteristic line A indicates a pressure characteristic when the one end portion 7a of the diaphragm spring 7 exists at a certain position. A characteristic line B indicates a pressure characteristic when the one end portion 7a of the diaphragm spring 7 is present at another certain position. According to the characteristic line A and the characteristic line B, as the gas flow rate increases, the secondary pressure P2 in the low pressure passage 71 gradually decreases.

  According to this embodiment, if the drive amount of the actuator 9 is adjusted as described above, the position of the movable body 92 can be adjusted, and consequently the urging force of the diaphragm spring 7 can be adjusted. L can be adjusted as appropriate. As a result, the characteristics of the flow rate of the fuel gas in the low pressure passage 71 and the set pressure (secondary pressure) can be changed. As a result, a plurality of forms can be realized with respect to the characteristics of the flow rate of the fuel gas in the low-pressure passage 71 and the set pressure (secondary pressure) as shown by the characteristic lines C and D shown in FIG.

  Further, regarding the characteristic of the flow rate of fuel gas in the low pressure passage 71-the set pressure (secondary pressure), as shown by the characteristic line E shown in FIG. 4, the secondary pressure P2 in the low pressure passage 71 is gradually increased as the gas flow rate increases. The secondary pressure P2 of the low-pressure passage 71 can be maintained in a certain range although the gas flow rate increases as shown by the characteristic line F shown in FIG.

  According to the fuel cell power generation system, the set pressure in the low pressure passage 71 tends to change frequently. In particular, according to the on-vehicle fuel cell power generation system, the set pressure (secondary pressure) in the low-pressure passage 71 tends to change frequently according to the vehicle load. In this respect, according to the present embodiment, the urging force of the diaphragm spring 7 is increased or decreased by driving the actuator 9, so that the responsiveness is good and the urging force of the diaphragm spring 7 can be increased or decreased at a high speed. Therefore, the throttle opening degree L of the throttle hole 40 can be adjusted quickly, and consequently the gas flow rate-set pressure characteristic of the low pressure passage 71 can be adjusted quickly. Therefore, it is suitable for an on-vehicle fuel cell power generation system. In particular, it is the actuator 9 that adjusts the urging force of the diaphragm spring 7 and does not involve a pilot valve, so that responsiveness can be improved.

(Embodiment 2)
FIG. 5 shows a second embodiment. This embodiment has basically the same configuration and function as the first embodiment. The parts having common functions are denoted by common reference numerals. In the following, different parts will be mainly described. According to the present embodiment, as shown in FIG. 5, the relationship between the drive position N (N _{1 to} N _n ) at the tip of the drive shaft 91 of the actuator 9 and the characteristics of the gas flow rate and the set pressure is previously mapped, The map is stored in a predetermined area of a storage medium such as a memory. When the gas flow rate signal is output from the control device of the fuel cell power generation system, the drive position of the drive shaft 91 of the actuator 9 is set so that the pressure of the low pressure passage 71 becomes the secondary pressure that can realize the gas flow rate. Control. As a result, the urging force of the diaphragm spring 7 is increased or decreased by driving the actuator 9. For this reason, the responsiveness is good, and the urging force of the diaphragm spring 7 can be increased or decreased at a high speed. Therefore, the throttle opening degree L of the throttle hole 40 can be adjusted quickly, and consequently the gas flow rate-set pressure characteristic of the low pressure passage 71 can be adjusted quickly. Therefore, it is suitable for an on-vehicle fuel cell power generation system. This can be expected to significantly improve the controllability and fuel consumption of the fuel cell power generation system. Note that the driving position N is generally grasped by detecting the value of the rotation or the position sensor, detecting the current value, or detecting the number of steps in the case of a stepping motor. .

(Embodiment 3)
FIG. 6 shows a third embodiment. This embodiment has basically the same configuration and function as the first embodiment. The parts having common functions are denoted by common reference numerals. In the following, different parts will be mainly described. According to the present embodiment, as shown in FIG. 6, a male screw portion 91 c is formed on the outer peripheral portion of the rotatable drive shaft 91 protruding from the actuator main body 90. Around the drive shaft 91, a movable body 92 is provided as a drive force transmission mechanism. In the cross section of the movable body 92, the outer wall surface 92p has an elliptical shape. The entire outer wall surface 92p of the movable body 92 is an engaging portion that engages with the engaged portion 2m of the body 2. As a result, the movable body 92 can move in the directions of arrows Y1, Y2 (opening direction and closing direction of the throttle hole 40) shown in FIG. 1, but in the circumferential direction (arrow R1 direction, arrow R2 direction) of the movable body 92. It is set so that it cannot move. A female screw portion 93 c is formed on the inner peripheral portion of the hole 93 formed in the central region of the movable body 92. The female screw portion 93c and the male screw portion 91c are screwed together so as to be able to advance and retract.

(Embodiment 4)
FIG. 7 shows a fourth embodiment. This embodiment has basically the same configuration and function as the first embodiment. The parts having common functions are denoted by common reference numerals. In the following, different parts will be mainly described. According to the present embodiment, as shown in FIG. 7, a movable body 92 as a driving force transmission mechanism is provided around the driving shaft 91. In the cross section of the movable body 92, the outer wall surface 92p has a quadrangular shape. The entire outer wall surface 92p of the movable body 92 is an engaging portion that engages with the engaged portion 2m of the body 2. As a result, the movable body 92 can move in the directions of arrows Y1 and Y2 (opening direction and closing direction of the throttle hole 40) shown in FIG. 1, but cannot be rotated in the circumferential direction (arrow R1 direction) of the movable body 92. Is set.

(Application form)
FIG. 8 shows an application form. According to this application mode, the fuel cell power generation system is for in-vehicle use or stationary use, and as shown in FIG. 8, the fuel cell 100 having the fuel electrode 101 and the oxidant electrode 102 and the fuel gas before power generation are used as fuel. Gas supply passage 5 for fuel supplied to the fuel electrode 101 of the battery 100 and gas supply for oxidant gas for supplying the oxidant gas (generally air) before power generation to the oxidant electrode 102 of the fuel cell 100 A passage 103, a gas discharge passage 105 for fuel off-gas through which the fuel off-gas after power generation passes through the valve 104, and a gas discharge passage 106 for oxidant off-gas through which the oxidant off-gas after power generation passes are provided. .

  The gas supply passage 5 is located upstream of the gas inlet of the fuel electrode 101 of the fuel cell 100. The gas supply passage 103 for the oxidant gas is provided with a compressor 107 which is a gas supply source for supplying the oxidant gas to the oxidant electrode 102 of the fuel cell 100. In the gas supply passage 5 for fuel, the pressure reducing valve 108 is provided on the gas supply source 55 side which is a high pressure fuel gas source, and the gas pressure reducing valve 1 described above is further provided downstream of the pressure reducing valve 108. Yes.

  According to this application mode, the relatively high-pressure fuel gas discharged from the gas supply source 55 is decompressed by the decompression valve 108, and further decompressed to a predetermined set pressure via the gas decompression valve 1. It is supplied to the fuel electrode 101 and used for power generation reaction. The oxidant gas (generally air) is supplied to the oxidant electrode 102 of the fuel cell 100 by driving the compressor 107 and used for the power generation reaction.

  As described above, according to this application mode, the urging force of the diaphragm spring 7 of the gas pressure reducing valve 1 is increased or decreased by driving the actuator 9. Therefore, the responsiveness is good, and the urging force of the diaphragm spring 7 can be increased or decreased at a high speed. Therefore, the throttle opening L of the throttle hole 40 of the gas pressure reducing valve 1 can be quickly adjusted, and the gas flow rate-set pressure characteristic of the low pressure passage 71 can be quickly adjusted. Therefore, it is suitable for an on-vehicle or stationary fuel cell power generation system.

(Other)
According to the above-described embodiment, the gas pressure reducing valve 1 is used as a pressure reducing valve for fuel gas sent to the fuel electrode 101 of the fuel cell 100. However, the present invention is not limited to this, and the oxidant electrode (air electrode) of the fuel cell 100 is used. ) It may be used as a pressure reducing valve for the oxidant gas sent to 102. According to the above-described embodiment, the diaphragm spring 7 and the valve spring 8 are coil springs. However, the present invention is not limited to this and may be other types of springs such as a leaf spring, or may be formed of rubber, soft resin, or the like. May be. In addition, the present invention is not limited to the embodiment described above and shown in the drawings, and can be implemented with appropriate modifications without departing from the scope of the invention.

  The present invention can be used for a fuel cell power generation system used for applications such as vehicles, stationary, and portable.

1 is a cross-sectional view of a gas pressure reducing valve according to Embodiment 1. FIG. It is sectional drawing of the drive shaft vicinity of an actuator. It is a graph which shows the relationship between a gas flow rate and a secondary pressure. It is a graph which shows the relationship (target) between a gas flow rate and a secondary pressure. FIG. 10 is a diagram in which a relationship between a drive position N (N1 to Nn) of a drive shaft of an actuator and a gas flow rate-set pressure characteristic is mapped according to the second embodiment. FIG. 10 is a cross-sectional view of a vicinity of a movable body according to a third embodiment and provided in a gas pressure reducing valve. FIG. 10 is a cross-sectional view of the vicinity of a movable body provided in a gas pressure reducing valve according to a fourth embodiment. It is a lineblock diagram showing typically a fuel cell power generation system.

Explanation of symbols

  In the figure, 1 is a gas pressure reducing valve, 20 diaphragm chamber, 23 is a valve chamber, 3 is a diaphragm, 61 is a high pressure passage (primary side passage), 71 is a low pressure passage (secondary side passage), and 4 is a throttle opening adjustment. Mechanism, 40 is a throttle hole, 41 is a movable valve, 6 is a high pressure passage (primary side passage), 7 is a diaphragm spring (elastic member), 8 is a valve spring (biasing member for the movable valve), 100 is a fuel cell, 101 Indicates a fuel electrode, and 102 indicates an oxidizer electrode.

Claims (5)

A fuel cell having a fuel electrode and an oxidant electrode;
A fuel gas supply passage for supplying fuel gas to the fuel electrode of the fuel cell;
A gas supply passage for an oxidant gas for supplying an oxidant gas to the oxidant electrode of the fuel cell;
A fuel cell power generation system comprising a gas pressure reducing valve for a fuel cell power generation system provided upstream of the fuel cell in at least one of the gas supply passage for fuel and the gas supply passage for oxidant gas;
The fuel cell power generation system gas pressure reducing valve is:
A diaphragm chamber,
A deformable diaphragm that divides the diaphragm chamber into a first chamber and a second chamber;
A primary passage to which a gas containing an active material used in the fuel cell is supplied;
A secondary side passage connected to the fuel electrode or the oxidant electrode of the fuel cell via the first chamber;
Provided between the primary passage and the secondary passage, the gas flow rate in the primary passage is reduced, and the gas in the primary passage is supplied to the secondary passage through the first chamber. A throttle opening variable mechanism;
An elastic member that exerts a biasing force that biases the diaphragm in a direction to increase or decrease the throttle opening of the throttle opening variable mechanism;
And an actuator for adjusting an urging force of the elastic member. A gas pressure reducing valve used in a fuel cell power generation system connected to a fuel electrode or an oxidant electrode of a fuel cell,
A diaphragm chamber,
A deformable diaphragm that divides the diaphragm chamber into a first chamber and a second chamber;
A primary passage to which a gas containing an active material used in a fuel cell is supplied;
A secondary passage connected to the fuel electrode or the oxidant electrode of the fuel cell via the first chamber;
Provided between the primary passage and the secondary passage, the gas flow rate in the primary passage is reduced, and the gas in the primary passage is supplied to the secondary passage through the first chamber. A throttle opening variable mechanism;
An elastic member that exerts a biasing force that biases the diaphragm in a direction to increase or decrease the throttle opening of the throttle opening variable mechanism;
A gas pressure reducing valve for a fuel cell power generation system, comprising an actuator for adjusting an urging force of the elastic member.   3. The gas pressure reducing valve for a fuel cell power generation system according to claim 2, wherein a driving force transmission mechanism is provided between the actuator and the diaphragm.   4. The gas pressure reducing valve for a fuel cell power generation system according to claim 2, wherein the actuator is a motor or a solenoid.   The throttle opening variable mechanism according to any one of claims 2 to 4, wherein the throttle opening varying mechanism includes a throttle hole provided between the primary side passage and the secondary side passage, a valve chamber, A gas for a fuel cell power generation system, comprising: a movable valve provided in the valve chamber and facing the throttle hole; and a movable valve biasing member that biases the movable valve in a direction to close the throttle hole. Pressure reducing valve.

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