JP2011069310A - Ejector device for fuel cell - Google Patents

Abstract

To stably and accurately hold a position where an opening area between a nozzle hole and a needle is maximized.
SOLUTION: A nozzle 62 having a nozzle hole 62a for discharging hydrogen supplied through an inlet port 32a, and hydrogen discharged from the nozzle hole 62a and discharged from the fuel cell 12 through a circulation passage 24. A diffuser 78 that mixes the generated hydrogen off-gas, a stator 56 that is fixed to the ejector body 22a, a needle 58 that is fixed to the stator 56 and extends along the axial direction into the hollow portion of the nozzle 62, and a nozzle A ring 48 that is provided in a holder 48 that is integrally displaced with 62 and abuts against the stator 56 to maintain the opening area in the gap 68 between the nozzle hole 62a and the outer peripheral surface of the tip of the needle 58 at the maximum position. And a flange portion 48d.
[Selection] Figure 2

Description

  The present invention relates to an ejector device for a fuel cell that is incorporated in a fuel cell system and mixes and recirculates a fuel off-gas discharged from the fuel cell with a newly supplied fuel gas.

  For example, in a fuel cell system, in order to improve the power generation efficiency of the fuel cell, the fuel off gas (hydrogen off gas) discharged from the fuel cell is mixed with the newly supplied fuel gas (hydrogen gas) and recirculated. Is used.

  With regard to this type of ejector, for example, Patent Document 1 discloses a needle that is displaceable along a nozzle hole of a nozzle, and a fluid that is provided inside the nozzle and to which fuel gas is supplied via a fuel supply pipe. A passage, a first diaphragm fixed to the proximal end portion of the needle and closing the upstream end of the fluid passage, and a second diaphragm fixed to the proximal end portion of the needle and disposed opposite to the first diaphragm are provided. The pressure of the fuel gas supplied to the fluid passage, the first fluid pressure supplied to the chamber between the first diaphragm and the second diaphragm, and the chamber between the second diaphragm and the housing. A variable flow ejector is disclosed that mechanically controls the flow rate of fluid discharged from the nozzle by the second fluid pressure supplied to the nozzle.

JP 2002-227799 A

  However, in the variable flow rate ejector disclosed in Patent Document 1, the needle and the first diaphragm are easily affected by the supply pressure of the fuel gas supplied through the fuel supply pipe, and the nozzle hole and the outer peripheral surface of the needle There is a possibility that it is difficult to hold the needle accurately at the maximum position of the opening area in the gap.

  The present invention has been made in view of the above points, and provides an ejector device for a fuel cell that can stably and accurately hold a position where the opening area between the nozzle hole and the needle is maximized. The purpose is to provide.

  To achieve the above object, the present invention is connected to an inlet port to which fuel gas is supplied from the fuel gas supply means, an outlet port connected to a fuel gas supply passage communicating with the fuel cell, and a circulation passage. An ejector body provided with a suction port through which fuel off-gas discharged and returned from the fuel cell is sucked, a nozzle having a nozzle hole for discharging fuel gas supplied through the inlet port, and the nozzle hole A diffuser for mixing the fuel gas discharged from the fuel gas and the fuel off-gas discharged from the fuel cell through the circulation passage, a stator fixed to the ejector body, a stator fixed to the stator and the nozzle A needle extending along the axial direction in the hollow portion; and a displacement mechanism for displacing the nozzle along the axial direction of the needle; Maximum position holding means for holding the opening area in the gap between the nozzle hole of the nozzle and the outer peripheral surface of the tip of the needle at a maximum position, and the maximum position holding means is a holder that is displaced integrally with the nozzle. It consists of a flange part which is provided in and contacts the stator.

  According to the present invention, the flange portion provided on the holder abuts (sits) on the stator fixed to the ejector body, so that the opening area in the gap between the nozzle hole and the needle is stably at a position where the opening area is maximized. In addition, it can be held with high accuracy. As a result, in the present invention, stable flow rate control characteristics of the fuel gas discharged from the nozzle hole of the nozzle can be obtained.

  In other words, in the present invention, when the nozzle and the holder are integrally displaced and then returned to the initial state, the fuel gas (hydrogen) is discharged only by the flange portion of the holder coming into contact with the stator fixed to the ejector body. The gap to be formed can be easily set to the maximum opening area. Therefore, in the present invention, for example, it is not necessary to set the maximum opening area by relatively displacing the nozzle and the needle by electrical control of an electromagnetic valve or the like. As a result, according to the present invention, it is possible to suppress power consumption without requiring electrical control, and it can be easily manufactured with a simple mechanical structure.

  Further, according to the present invention, the holder is provided with a guide portion that slides along the outer diameter surface of the stator and guides the holder along the axial direction, thereby ensuring concentricity between the nozzle and the needle. However, the holder and the nozzle can be displaced smoothly and integrally.

  Furthermore, according to the present invention, the guide portion extends in a direction substantially orthogonal to the flange portion and is provided in close proximity to the flange portion, thereby reducing the number of parts and reducing the manufacturing cost. In addition, when the flange portion of the holder comes into contact with the stator while being guided by the guide portion, vibration at the time of contact is propagated to the guide portion side and generation of vibration is suppressed. Therefore, it is possible to suppress the vibration generated at the time of contact from being transmitted to the interior of the fuel cell vehicle (not shown).

  According to the present invention, it is possible to obtain a fuel cell ejector device capable of stably and accurately maintaining a position where the opening area between the nozzle hole and the needle is maximized.

1 is a block configuration diagram of a fuel cell system incorporating an ejector according to an embodiment of the present invention. It is a longitudinal cross-sectional view along the axial direction of the ejector. It is a schematic explanatory drawing of the nozzle and holder which comprise the said ejector. 3 is a longitudinal sectional view showing a state in which the nozzle and the holder are integrally displaced and the opening area of the nozzle hole is changed in the ejector of FIG.

  Next, embodiments of the present invention will be described in detail with reference to the drawings as appropriate. FIG. 1 is a block diagram of a fuel cell system incorporating an ejector according to an embodiment of the present invention.

  As shown in FIG. 1, a fuel cell system 10 includes a fuel cell 12 and a hydrogen tank (fuel gas supply) that is filled with high-pressure hydrogen gas and supplies the hydrogen gas as fuel gas to the fuel cell 12. Means) 14, an air compressor 16 for supplying compressed air containing oxidant gas (oxygen) to the fuel cell 12, unreacted hydrogen discharged from the fuel cell 12 as gas (hydrogen) and liquid ( And a gas-liquid separation and dilution unit 18 for diluting the separated hydrogen with unreacted air discharged from the fuel cell 12.

  The fuel cell 12 is composed of, for example, a solid polymer electrolyte fuel cell (PEFC), and is mounted on a vehicle such as a fuel cell vehicle (not shown). The fuel cell 12 has a stack body (not shown) formed by stacking a plurality of single cells (not shown), an anode to which hydrogen is supplied as a fuel gas, and oxygen as an oxidant gas, for example. And a cathode supplied with air.

  A hydrogen supply passage (fuel gas supply passage) 20 is provided between the hydrogen tank 14 and the fuel cell 12, and an ejector 22 that functions as a fuel cell ejector device is disposed in the hydrogen supply passage 20. Established. This ejector 22 is connected to a circulation passage 24 that feeds back unreacted hydrogen (hereinafter referred to as hydrogen offgas) that is fuel offgas discharged from the fuel cell 12, and hydrogen and fuel cell that are newly supplied from the hydrogen tank 14. The hydrogen off-gas fed back from 12 is mixed and re-supplied (recirculated) to the fuel cell 12.

  A regulator or the like that introduces air from the air compressor 16 as a pilot pressure signal between the hydrogen tank 14 and the ejector 22 to regulate the pressure of hydrogen supplied to the fuel cell 12 to a predetermined pressure. A hydrogen pressure regulating unit (not shown) including is provided.

  An air supply passage 26 is provided between the air compressor 16 and the fuel cell 12, and a humidifier 28 that humidifies the dry air supplied from the air compressor 16 is disposed in the air supply passage 26. Is done. The air humidified by the humidifier 28 is introduced to the cathode side of the fuel cell 12 through the air supply passage 26.

  A branch passage 30 that branches from the air supply passage 26 is provided between the air compressor 16 and the humidifier 28. A downstream side of the branch passage 30 is connected to an ejector 22, and air (compressed air) supplied via the branch passage 30 is introduced to the ejector 22 as an air signal pressure.

  In the gas-liquid separation and dilution unit 18, for example, water accumulated in the anode of the fuel cell 12 or fuel gas containing nitrogen gas that has permeated the electrolyte membrane from the cathode and mixed into the anode is purged to a diluter (not shown). A hydrogen purge valve (not shown), a catch tank (not shown) that separates hydrogen gas containing water discharged from the fuel cell 12 into hydrogen and water, and a pipe line for discharging drain accumulated in the catch tank are opened and closed. A drain valve or the like (not shown) is provided.

Next, the ejector 22 will be described. FIG. 2 is a longitudinal sectional view along the axial direction of the ejector, and FIG. 3 is a schematic explanatory view of a nozzle and a holder constituting the ejector.
As shown in FIG. 2, the ejector 22 has an ejector body 22a, and the ejector body 22a is configured by integrally connecting a plurality of block bodies as will be described later.

  The ejector body 22a is connected to a hydrogen supply passage 20 through a filter (not shown) and connected to an inlet port 32a to which relatively high-pressure hydrogen is supplied from the hydrogen tank 14, and a hydrogen supply passage 20 communicating with the fuel cell 12. And an outlet port 32b through which a mixed gas obtained by mixing hydrogen supplied from the hydrogen tank 14 and hydrogen off-gas is discharged.

  The ejector body 22 a is connected to the circulation passage 24 and drawn out from the air compressor 16 through the branch passage 30 connected to the suction port 32 c through which the hydrogen off-gas is sucked through the circulation passage 24 and the branch passage 30. The air supply port 32d is supplied with air and the breathing port 32e communicates with the atmosphere.

  The ejector body 22a includes a first block body 34a provided with an air supply port 32d, a second block body 34b provided with a breathing port 32e, a third block body 34c, and a first block body provided with an inlet port 32a. It has a four block body 34d and a fifth block body 34e provided with an outlet port 32b and a suction port 32c. The first to third block bodies 34a to 34c are integrally fastened by a plurality of first fixing bolts 36 separated by a predetermined angle along the circumferential direction, and the third to fifth block bodies 34c to 34e are The bolts are fastened together by a plurality of second fixing bolts 38 spaced apart by a predetermined angle along the circumferential direction.

  A first diaphragm 40 having a relatively large diameter is disposed between the first block body 34a and the second block body 34b, and an outer peripheral edge portion of the first diaphragm 40 is disposed between the first block body 34a and the second block body. It is clamped by the body 34b. A second diaphragm 42 having a relatively small diameter is disposed between the third block body 34c and the fourth block body 34d so as to face the first diaphragm 40, and an outer peripheral edge portion of the second diaphragm 42 is provided. It is sandwiched between the third block body 34c and the fourth block body 34d. Further, a third diaphragm 44 having a relatively small diameter is disposed between the fourth block body 34d and the fifth block body 34e so as to face the second diaphragm 42, and an outer peripheral edge portion of the third diaphragm 44 is provided. It is sandwiched between the fourth block body 34d and the fifth block body 34e. In this case, the pressure receiving areas of the second diaphragm 42 and the third diaphragm 44 are set to be substantially the same.

  In addition, the first holding member 46a and the second holding member 46b provided with a disk portion 55a for holding the first diaphragm 40 on both the front and back surfaces, and the second diaphragm 42 are held on the front and back surfaces inside the ejector body 22a. The first and third holding members 46a to 46c penetrate through the center of the first to third holding members 46a to 46c, and the second holding member 46b and the third holding member 46c provided with the circular plate portion 55a. Are fixed to the fourth block body 34d of the ejector body 22a by a plurality of bolts 52, a nut member 50 that is fastened to a threaded portion of the holder 48 via a washer, and a plurality of bolts 52. A stator 56 having an annular recess 54 facing one end is provided.

  Further, a base end portion is fixed to the hole portion of the stator 56 inside the ejector body 22a, and a needle 58 extending in the axial direction into a hollow portion of a nozzle 62 described later, and a through hole of the stator 56 A connecting bolt 64 that is inserted through 60 and connects the holder 48 and the nozzle 62, and a nozzle hole 62a that is connected to the holder 48 via the connecting bolt 64 and that faces the tip 58a of the needle 58. 62 and a bearing member 66 fixed to the inner wall of the nozzle 62 and displaced integrally with the nozzle 62 and having a sliding hole 66a that slides along the needle 58 and a flow hole 66b through which fluid flows. Provided. In this case, the first to third holding members 46 a to 46 c are integrally fastened between the step portion 48 b of the holder 48 and the nut member 50.

  In the present embodiment, the needle 58 is held by the stator 56 fixed to the ejector body 22a to be a fixed side, the nozzle 62 is connected to the holder 48 via the connecting bolt 64, and the holder 48 and the nozzle 62 are integrated. In contrast to the above, the nozzle 62 may be provided on the fixed side and the needle 58 on the movable side so that the nozzle 62 and the needle 58 are relatively displaced.

  The first to third diaphragms 40, 42, 44, the first to third holding members 46 a to 46 c, the holder 48, and the connecting bolt 64 are displacement mechanisms that displace the nozzle 62 along the axial direction of the needle 58. It functions.

  As shown in FIG. 3, the holder 48 has a rod portion 48a extending a predetermined length along the axial direction, and extends slightly outward in the radial direction from the outer peripheral surface of the rod portion 48a. An annular stepped portion 48b having a diameter, a guide portion 48c formed in a sleeve shape continuously to the stepped portion 48b, and an annular flange portion 48d projecting from the outer peripheral surface of the guide portion 48c in a radially outward direction by a predetermined length. And have.

  In this case, the annular flange portion 48d of the holder 48 functions as a maximum position holding means (flange portion), and the annular flange portion 48d abuts on the disc portion 56a of the stator 56 to restrict the displacement thereof. Thus, the opening area in the gap 68 between the nozzle hole 62a of the nozzle 62 and the outer peripheral surface of the tip portion 58a of the needle 58 can be held (set) at the maximum position. The portion of the holder 48 that contacts the disc portion 56a of the stator 56 is not limited to the annular flange portion 48d, but may be a non-annular flange portion.

  The guide portion 48c of the holder 48 guides the holder 48 along the axial direction by sliding along the outer diameter surface 56b of the stator 56 when the holder 48 is displaced integrally with the nozzle 62. The function to perform. The guide portion 48c extends in a direction substantially orthogonal to the annular flange portion 48d, and is provided in close proximity to the annular flange portion 48d.

  Returning to FIG. 2, a first chamber 70a is formed by being partitioned by the inner wall of the first block body 34a and the first diaphragm 40, and the first chamber 70a is provided to communicate with the air supply port 32d. Further, a second chamber 70b is formed by being divided into a first diaphragm 40 and a second diaphragm 42, and the second chamber 70b is provided so as to communicate with the breathing port 32e. Furthermore, a third chamber 70c is formed by being partitioned by the second diaphragm 42 and the third diaphragm 44, and the third chamber 70c is provided so as to communicate with the inlet port 32a. Furthermore, a fourth chamber 70d is formed by being partitioned by the inner wall of the fourth block body 34d and the third diaphragm 44, and the fourth chamber 70d is provided so as to communicate with the suction port 32c.

  The first chamber 70a is provided with a first spring member 72a having one end engaged with the end cap 71 and the other end engaged with the first holding member 46a. The first spring member 72a has a spring force. Thus, the first to third holding members 46a to 46c and the holder 48 are provided to be pressed (biased) toward the nozzle 62 side. The fourth chamber 70d is provided with a second spring member 72b having one end engaged with the retainer 74 and the other end engaged with the seating surface 76 of the inner wall of the fourth block body 34d. The second spring member 72b is provided so as to press (bias) the nozzle 62 toward the holder 48 side by a spring force.

  In this case, the spring force of the first spring member 72a is set larger than the spring force of the second spring member 72b, and when no pressure fluid is supplied into the first chamber 70a and the fourth chamber 70d, the first spring Due to the difference in spring force between the member 72 a and the second spring member 72 b, the annular flange portion 48 d of the holder 48 abuts on the disc portion 56 a of the stator 56, and the outer peripheral surfaces of the nozzle hole 62 a of the nozzle 62 and the tip end portion 58 a of the needle 58. In the initial state, the opening area in the gap 68 is maintained at the maximum position.

  Further, the fourth block body 34 d of the ejector body 22 a has a diffuser 78 disposed on one end side along the axial direction of the nozzle 62 and provided coaxially with the nozzle 62.

  As shown in FIG. 3, the needle 58 faces the nozzle hole 62a and includes a tip portion 58a including a sharp pointed apex, a small diameter portion 58b extending from the tip portion 58a, and extending from the small diameter portion 58b. The taper portion 58c gradually increases in diameter, and the outer diameter portion 58d extends from the taper portion 58c and has an outer diameter set substantially constant along the axial direction.

  Returning to FIG. 2, the diffuser 78 includes a trumpet-shaped enlarged diameter portion 78a surrounding a part of the nozzle 62 having the nozzle hole 62a, and a cylindrical body continuous to the enlarged diameter portion 78a, and is directed toward the outlet port 32b. And a throat portion 78b having a linear passage that gradually increases in diameter.

  In this case, the nozzle 62, the needle 58, and the diffuser 78 are disposed so as to be coaxial (the three axes coincide). A suction chamber 80 is formed between the nozzle 62 and the diffuser 78, and the suction chamber 80 is provided so as to communicate with the suction port 32c.

  Due to the relationship between the air signal pressure introduced into the first chamber 70a and the pressure of the hydrogen off-gas introduced into the fourth chamber 70d, the first to third diaphragms 40, 42, 44 bend to cause the holder 48 to bend. The nozzle 62 is integrally displaced in the direction of the arrow X1, and the opening area in the gap 68 between the nozzle hole 62a through which hydrogen is injected toward the diffuser 48 and the tip 58a of the needle 58 can be changed.

  The fuel cell system 10 in which the ejector 22 according to the present embodiment is incorporated is basically configured as described above. Next, the function and effect will be described.

  First, when the power generation of the fuel cell 12 is stopped, the supply of hydrogen from the hydrogen tank 14 is shut off by a shut-off valve (not shown), and the supply of hydrogen to the inlet port 32a of the ejector 22 is stopped. At the same time, the driving of the air compressor 16 is stopped, and the supply of compressed air to the air supply port 32d of the ejector 22 is stopped.

  In this case, since the spring force of the first spring member 72a is set larger than the spring force of the second spring member 72b, the holder 48 depends on the difference in spring force between the first spring member 72a and the second spring member 72b. The annular flange portion 48d contacts the disc portion 56a of the stator 56, and the opening area in the gap 68 between the nozzle hole 62a of the nozzle 62 and the outer peripheral surface of the tip end portion 58a of the needle 58 is maintained at the maximum position. Yes (see FIG. 2).

  In this initial state, as shown by the solid line in FIG. 3, the tip 58a of the needle 58 slightly protrudes outward from the nozzle hole 62a. Therefore, the opening area (gap 68) of the nozzle hole 62a through which hydrogen is discharged is obtained by subtracting the outer diameter area of the tip 58a of the needle 58 from the inner diameter area of the nozzle hole 62a.

  On the other hand, at the time of power generation of the fuel cell 12, a shut-off valve (not shown) is opened so that hydrogen is supplied from the hydrogen tank 14 to the anode of the fuel cell 12 through the hydrogen supply passage 20, and an air compressor 16 is driven, and the air humidified by the humidifier 28 is supplied to the cathode of the fuel cell 12 through the air supply passage 26.

  In the ejector 22, relatively high-pressure hydrogen from the hydrogen tank 14 is supplied through the inlet port 32a, and is supplied to the third chamber 70c partitioned by the second diaphragm 42 and the third diaphragm 44 in the ejector body 22a. At the same time, the compressed air from the air compressor 16 is supplied into the first chamber 70a partitioned by the first diaphragm 40 through the branch passage 30 and the air supply port 32d.

  At this time, when the pressure of the hydrogen off-gas introduced into the fourth chamber 70d is equal to or lower than the pressure of compressed air (air signal pressure) in the first chamber 70a, the annular flange portion 48d of the holder 48 as in the initial state. Is brought into contact with the disk portion 56a of the stator 56, and the opening area in the gap 68 between the nozzle hole 62a of the nozzle 62 and the outer peripheral surface of the distal end portion 58a of the needle 58 is kept in the maximum position.

  The hydrogen introduced into the third chamber 70c of the ejector 22 is further introduced into the hollow portion of the nozzle 62 through the flow hole 66b of the bearing member 66 fitted in the nozzle 62, and then the nozzle hole 62a and the needle The liquid is discharged toward the diffuser 78 through a gap 68 (maximum opening area) of the front end portion 58a of 58. The hydrogen whose flow rate is reduced by the nozzle hole 62a is accelerated and flows along the throat portion 78b of the diffuser 78, and is supplied to the fuel cell 12 from the outlet port 32b along the hydrogen supply passage 20.

  At the same time, when hydrogen is injected (discharged) from the tip of the nozzle hole 62a of the nozzle 62 toward the diffuser 78, a negative pressure is generated at a portion between the nozzle 62 and the enlarged diameter portion 78a of the diffuser 78 by a so-called jet pump effect. Action occurs. Due to this negative pressure action, the hydrogen off-gas in the suction chamber 80 is sucked, and the hydrogen discharged from the nozzle 62 and the hydrogen off-gas sucked through the suction port 32c are mixed by the diffuser 78, and the hydrogen is supplied from the outlet port 32b to the hydrogen supply passage 20. Derived.

4 is a longitudinal sectional view showing a state where the nozzle and the holder are integrally displaced and the opening area of the nozzle hole is changed in the ejector of FIG.
In the operating state of the fuel cell 12, the pressure of compressed air (air signal pressure) introduced into the first chamber 70a via the branch passage 30 and the air supply port 32d was introduced via the suction port 32c. When the pressure of the hydrogen off gas in the fourth chamber 70d becomes high, the pressing force by the hydrogen off gas overcomes the spring force of the first spring member 72a to bend the first to third diaphragms 40, 42, 44, and the holder Under the guiding action of the 48 guide portions 48c, the holder 48 and the nozzle 62 are integrally displaced along the direction of the arrow X1 (see FIG. 4).

  Therefore, as indicated by a two-dot chain line in FIG. 3, the tip 58 a, the small diameter 58 b and the taper 58 c of the needle 58 are in a state of being exposed to the outside from the tip of the nozzle hole 62 a of the nozzle 62. As a result, since the hydrogen introduced into the hollow portion of the nozzle 62 is discharged toward the diffuser 78 through the minute gap 68 of the nozzle hole 62a, a relatively small flow rate of hydrogen is supplied to the fuel cell 12. Can do. In this manner, the supply of a relatively large flow rate of hydrogen can be switched to the supply of a relatively small flow rate of hydrogen by the displacement of the holder 48 and the nozzle 62.

  In the present embodiment, an annular flange portion 48 d that abuts on the disk portion 56 a of the stator 56 and restricts the displacement of the holder 48 is provided at a portion that is formed to protrude outward in the radial direction of the holder 48. In the present embodiment, by providing the holder 48 with the annular flange portion 48d, the holder 48 and the nozzle 62 are integrally displaced in the direction of the arrow X1 due to the pressure relationship between the first chamber 70a and the fourth chamber 70d. When the first spring member 72a is displaced in the direction of the arrow X2 by the spring force of the first spring member 72a and returns to the initial state again, the annular flange portion 48d provided in the holder 48 contacts (seats) the disc portion 56a of the stator 56. By doing so, the opening area in the gap 68 between the nozzle hole 62a and the needle 58 can be stably and accurately held at a position where the opening area is maximized. As a result, in this embodiment, a stable flow rate control characteristic of hydrogen discharged from the nozzle hole 62a of the nozzle 62 can be obtained.

  In other words, in this embodiment, when the annular flange portion 48d of the holder 48 that is displaced together with the nozzle 62 returns to the initial state, the annular flange portion 48d of the holder 48 is fixed to the ejector body 22a. The gap 68 from which hydrogen is discharged can be easily set to the maximum opening area simply by contacting the nozzle 62 and the nozzle 62 and the needle 58 are relatively displaced by electrical control such as a solenoid valve. Therefore, it becomes unnecessary to set the maximum opening area. As a result, in this embodiment, electric control is not required and power consumption can be suppressed, and manufacturing can be easily performed with a simple mechanical structure.

  In the present embodiment, the first to third diaphragms 40, 42, 44 are bent by the compressed air supplied via the branch passage 30 and the air supply port 32d, and the first to third diaphragms 40, 42, By displacing the holder 48 and the nozzle 62 in conjunction with 44, electrical control is unnecessary and power consumption can be further suppressed.

  Further, in the present embodiment, the holder 48 is provided with a guide portion 48c that slides along the outer diameter surface 56b of the stator 56 and guides the holder 48 along the axial direction. The holder 48 and the nozzle 62 can be smoothly displaced while ensuring concentricity. In this case, the guide portion 48c of the holder 48 is provided so as to be able to enter the annular recess 54 of the stator 56, thereby extending the length of the guide portion 48c that slides on the outer diameter surface 56b of the stator 56, thereby providing a guide function. Can be increased.

  Furthermore, in the present embodiment, the guide portion 48c extends in a direction substantially orthogonal to the annular flange portion 48d and is provided in close proximity to the annular flange portion 48d, thereby reducing the number of parts and manufacturing costs. When the annular flange portion 48d of the holder 48 abuts on the disk portion 56a of the stator 56 while being guided by the guide portion 48c, vibration at the time of contact propagates to the guide portion 48c side. Generation of vibration is suppressed. Therefore, it is possible to suppress the vibration generated at the time of contact from being transmitted to the interior of the fuel cell vehicle (not shown).

DESCRIPTION OF SYMBOLS 10 Fuel cell system 12 Fuel cell 14 Hydrogen tank (fuel gas supply means)
20 Hydrogen supply passage (fuel gas supply passage
22 Ejector (Ejector device for fuel cell) 22a Ejector body 24 Circulating passage 32a Inlet port 32b Outlet port 32c Suction port 40, 42, 44 Diaphragm (displacement mechanism)
48 holder 48c guide portion 48d annular flange portion (maximum position holding means) 56 stator 56b outer diameter surface 58 needle 58a tip portion 62 nozzle 62a nozzle hole 68 gap 78 diffuser

Claims (3)

An inlet port to which fuel gas is supplied from the fuel gas supply means, an outlet port connected to a fuel gas supply passage communicating with the fuel cell, and a fuel off-gas exhausted from the fuel cell and returned to the circulation passage. An ejector body provided with a suction port,
A nozzle having a nozzle hole for discharging the fuel gas supplied through the inlet port;
A diffuser that mixes the fuel gas discharged from the nozzle hole and the fuel off-gas discharged and returned from the fuel cell through the circulation passage;
A stator fixed to the ejector body;
A needle fixed to the stator and extending along the axial direction in the hollow portion of the nozzle;
A displacement mechanism for displacing the nozzle along the axial direction of the needle;
Maximum position holding means for holding the opening area in the gap between the nozzle hole of the nozzle and the outer peripheral surface of the tip of the needle at the maximum position;
With
The ejector device for a fuel cell, wherein the maximum position holding means includes a flange portion that is provided on a holder that is integrally displaced with the nozzle and contacts the stator. The ejector device for a fuel cell according to claim 1,
An ejector device for a fuel cell, wherein the holder is provided with a guide portion that slides along an outer diameter surface of the stator and guides the holder along an axial direction. The ejector device for a fuel cell according to claim 2,
The fuel cell ejector device, wherein the guide portion extends in a direction substantially orthogonal to the flange portion and is provided integrally with the flange portion.

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