U.S. patent application number 12/223484 was filed with the patent office on 2009-01-15 for valve, valve controller, and fuel cell system.
This patent application is currently assigned to TOYOTA JIDOSHA KABUSHIKI KAISHA. Invention is credited to Tsukuo Ishitoya, Masahiro Takeshita.
Application Number | 20090014089 12/223484 |
Document ID | / |
Family ID | 38474739 |
Filed Date | 2009-01-15 |
United States Patent
Application |
20090014089 |
Kind Code |
A1 |
Takeshita; Masahiro ; et
al. |
January 15, 2009 |
Valve, Valve Controller, and Fuel Cell System
Abstract
Provided are a valve being able to adjust a flow rate of fluid
out of a tank with a high accuracy, a valve controller, and a fuel
cell system. The valve is configured to adjust the flow rate of
fluid to the secondary side. The valve is disposed on the tank so
that the secondary side is a discharge side for fluid from inside
the tank. The valve is configured to adjust the flow rate of fluid
from the tank by a duty control.
Inventors: |
Takeshita; Masahiro; (Aichi,
JP) ; Ishitoya; Tsukuo; (Aichi, JP) |
Correspondence
Address: |
KENYON & KENYON LLP
1500 K STREET N.W., SUITE 700
WASHINGTON
DC
20005
US
|
Assignee: |
TOYOTA JIDOSHA KABUSHIKI
KAISHA
Toyota-shi, Aichi-ken
JP
|
Family ID: |
38474739 |
Appl. No.: |
12/223484 |
Filed: |
February 6, 2007 |
PCT Filed: |
February 6, 2007 |
PCT NO: |
PCT/JP2007/052438 |
371 Date: |
July 31, 2008 |
Current U.S.
Class: |
141/192 |
Current CPC
Class: |
F17C 2205/0317 20130101;
F17C 2250/0626 20130101; H01M 8/04753 20130101; H01M 8/0432
20130101; F17C 2201/0109 20130101; F17C 2203/066 20130101; F16K
31/0648 20130101; F17C 2270/0763 20130101; Y02E 60/32 20130101;
F17C 2223/036 20130101; F17C 2250/0636 20130101; F16K 1/305
20130101; F17C 2260/018 20130101; F17C 2270/0518 20130101; H01M
8/04089 20130101; F17C 2270/0184 20130101; F17C 2203/0663 20130101;
F17C 2250/0439 20130101; H01M 8/04223 20130101; F17C 2203/0619
20130101; F17C 2223/0123 20130101; F17C 2221/012 20130101; F17C
2270/0168 20130101; F17C 2270/05 20130101; F17C 2250/032 20130101;
F17C 2260/015 20130101; F17C 2221/033 20130101; F17C 2201/056
20130101; H01M 8/0438 20130101; F17C 2227/0135 20130101; H01M
8/04097 20130101; Y02E 60/50 20130101; F17C 2225/036 20130101; F17C
2203/0604 20130101; F17C 2205/0391 20130101; F17C 2250/043
20130101; H01M 8/04201 20130101; H01M 8/04228 20160201; F17C
2205/0305 20130101; F17C 2270/0105 20130101; F17C 2205/0326
20130101; F17C 2205/0332 20130101; F17C 2205/0394 20130101; F16K
31/0644 20130101; F17C 2270/0173 20130101; F17C 13/04 20130101;
F17C 2205/0335 20130101; F17C 2205/0338 20130101; F17C 2225/0123
20130101; F17C 2227/0157 20130101 |
Class at
Publication: |
141/192 |
International
Class: |
B65B 3/00 20060101
B65B003/00 |
Foreign Application Data
Date |
Code |
Application Number |
Mar 6, 2006 |
JP |
2006-060128 |
Claims
1. An injector for adjusting a flow rate of hydrogen gas to a
secondary side, wherein the injector is disposed on a mouthpiece
portion of a tank so that the secondary side is a discharge side
for the hydrogen gas from inside the tank, and the flow rate of the
hydrogen gas from the tank to a fuel cell is configured to be
adjustable by a duty control, and wherein the axis line of the
injector is parallel to the axis line of the tank.
2. The injector according to claim 1, comprising a flow rate
adjusting mechanism for adjusting the flow rate by the duty
control, wherein the flow rate adjusting mechanism is configured to
block a discharge of the hydrogen gas from the tank.
3. The injector according to claim 2, wherein the flow rate
adjusting mechanism comprises a valve body, a valve seat that comes
into contact/breaks contact with the valve body, and a solenoid for
urging the valve body in directions in which the valve body comes
into contact/breaks contact with the valve seat.
4. The injector according to claim 3, wherein the valve seat has an
opening at a center thereof, and wherein an area of the opening is
changed depending on a position of the valve body.
5. The injector according to claim 3, wherein the duty control is
performed by changing a duty ratio of pulse-like excitation current
supplied to the solenoid.
6. The injector according to claim 3, wherein the flow rate
adjusting mechanism is configured to apply a pressure in the tank
to the valve body in a direction in which the valve body comes into
contact with the valve seat.
8. (canceled)
9. The injector according to claim 1, wherein a main stop valve
independent of the injector is disposed on the tank, and wherein
the main stop valve is located on a primary side of the
injector.
10. The injector according to claim 9, wherein the main stop valve
is located in the tank.
11. A valve controller for controlling the injector according to
claim 1 by the duty control.
12. A fuel cell system comprising: the injector according to claim
1; the tank; and a fuel cell supplied with oxidant gas and hydrogen
gas.
13. A fuel cell system comprising: the injector according to claim
1; a tank storing the hydrogen gas; a fuel cell supplied with the
hydrogen gas from the tank; and a main stop valve disposed on the
tank so that the main stop valve is located at a primary side of
the injector, wherein the main stop valve is closed at a time of
stopping of operation of the fuel cell system.
Description
TECHNICAL FIELD
[0001] The present invention relates to a valve which is able to
adjust a flow rate of fluid to a secondary side, a valve controller
for the valve, and a fuel cell system provided with the valve.
BACKGROUND ART
[0002] Hitherto, supply systems supplying fuel stored in a tank to
a fuel consuming apparatus are widely known. For example, in a
supply system described in Japanese Patent Publication No.
2005-42924, hydride fluid stored in a tank is supplied to
semiconductor manufacturing equipments. The tank is provided with a
mechanical type regulator valve for adjusting the pressure of the
hydride fluid supplied from the tank to the exterior.
DISCLOSURE OF THE INVENTION
[0003] However, it is not possible to precisely adjust the flow
rate of fuel from tank by the use of the regulator valve attached
to the tank. In addition, since the regulator valve is of a
mechanical type, the response property is relatively low.
[0004] An object of the invention is to provide a valve being able
to adjust a flow rate of fluid from a tank, a valve controller for
the valve, and a fuel cell system having the valve.
[0005] In order to accomplish the above object, a valve according
to the invention is configured to adjust a flow rate of fluid to a
secondary side and is disposed on a tank so that the secondary side
is a discharge side for fluid from inside the tank. The valve is
configured so that the flow rate of the fluid from the tank is
adjusted by a duty control.
[0006] According to the configuration, since the valve which is
able to adjust the flow rate of the fluid by the duty control is
disposed on the tank, it is possible to adjust the flow rate of the
fluid from the tank at high accuracy.
[0007] Here, the configuration in which the valve is disposed on
the tank can employ a configuration in which the valve is disposed
inside the tank, a configuration in which the valve is directly or
indirectly attached to an element of the tank and is disposed
outside the tank, or a configuration in which a part of the valve
is disposed inside the tank and the other of the valve is disposed
outside the tank. In arranging the valve, the valve may be attached
to a mouthpiece of the tank, or the valve and another valve may
form a valve assembly and the valve assembly may be screwed to be
engaged in the mouthpiece of the tank.
[0008] Preferably, the valve may further include a flow rate
adjusting mechanism to adjust the flow rate by the duty control.
The flow rate adjusting mechanism may be configured to block the
discharge of the fluid from the tank.
[0009] According to the configuration, the valve may be made to
serve as a shutoff valve.
[0010] Here, the flow rate adjusting mechanism may include a valve
body, a valve seat which the valve body comes into contact/breaks
contact with, and a solenoid for urging the valve body in
directions in which the valve body comes into contact/breaks
contact with the valve seat. In this configuration, an axial
direction of the valve is in coincidence with a direction in which
the valve body comes into contact/breaks contact with the valve
seat. It is preferable that the valve seat may be more elastic than
a base member of the valve or the valve body. Accordingly, it is
possible to improve the function of the valve as a shutoff valve.
It is preferable that the valve has such a configuration that the
valve body comes into contact with the valve seat with the pressure
(primary pressure) of the tank to block the discharge of the
fluid.
[0011] Preferably, the axis line of the valve and the axis line of
the tank may be substantially parallel to or coincident with each
other.
[0012] According to the configuration, the valve can be made to
have an easy self cleaning structure. For example, when the valve
has the above-mentioned configuration, the contamination such as
powdery abrasion dust generated at the time of movement of the
valve body may be discharged to the secondary side by the flow of
fluid from the primary side to the secondary side.
[0013] On the other hand, the valve generally tends to increase in
a length thereof in the axial direction as a whole. Accordingly,
when the axis line of the valve and the axis line of the tank are
coincident with each other, the total length of the valve and the
tank is apt to be elongated.
[0014] Accordingly, from a viewpoint of relatively reducing the
total length of the valve and the tank, the valve may be located
outside the body of the tank and the axis line of the valve and the
axis line of the tank may be substantially orthogonal to each
other.
[0015] According to the configuration, the installation space
occupied by installing of the valve and the tank cannot be
extremely large.
[0016] In a preferred embodiment of the present invention, the tank
may be provided with a main stop valve independent from the
above-said valve may be provided for the tank. The main stop valve
may be located at the primary side of the above-described
valve.
[0017] According to the configuration, it is possible to suppress
the fluid pressure acting on the valve by closing the main stop
valve. It is also possible to accomplish fail safe of the entire
system of the tank.
[0018] More preferably, the main stop valve may be located more
inside the tank than the mouthpiece portion of the tank and the
valve may be located outside the body of the tank.
[0019] In order to accomplish the above object, a valve controller
according to the invention accomplishes the duty control of the
above-mentioned valve of the invention.
[0020] With the configuration, it is possible to adequately
duty-control the valve and thus to minutely adjust the flow rate of
the fluid from the tank to the outside.
[0021] In order to achieve the afore-mentioned object, a fuel cell
system according to the invention includes the above-mentioned
valve; the tank; and a fuel cell supplied with oxidant gas and fuel
gas. The fluid in the tank is fuel gas.
[0022] With the configuration, it is possible to supply the fuel
gas, the flow rate of which has been adjusted by the valve, to the
fuel cell. Hence, it is possible to supply desired fuel gas from
the tank with a high response property in correspondence with the
amount of consumption of the fuel gas in the fuel cell.
[0023] According to another aspect of the present invention, there
is provided a fuel cell system including: the above-mentioned
valve; a tank capable of storing fuel gas; a fuel cell supplied
with the fuel gas from the tank; and a main stop valve disposed on
the tank so that the main stop valve is located at a primary side
of the valve. The main stop valve is closed at the time of stopping
of the operation of the fuel cell system.
BRIEF DESCRIPTION OF THE DRAWINGS
[0024] FIG. 1 is a diagram illustrating a configuration of a fuel
cell system according to a first embodiment of the invention.
[0025] FIG. 2 is a sectional view illustrating structures of a
valve and a tank according to the first embodiment of the
invention.
[0026] FIG. 3 is a sectional view illustrating structures of a
valve and a tank according to a second embodiment of the
invention.
BEST MODE FOR CARRYING OUT THE INVENTION
[0027] Hereinafter, a fuel cell system having a valve according to
embodiments of the invention will be described with reference to
the accompanying drawings. In the fuel cell system, a valve under
duty control is disposed on a tank to adjust a flow rate of fuel
gas from the tank. In the following description, an injector is
described as an example of the valve under duty control.
FIRST EMBODIMENT
[0028] As shown in FIG. 1, a fuel cell system 1 includes a fuel
cell 2, an oxidant gas piping system 3 supplying air (oxygen) as
oxidant gas to the fuel cell 2, a fuel gas piping system 4
supplying hydrogen gas as fuel gas to the fuel cell 2, and a
controller 7 generally controlling the entire system.
[0029] The fuel cell 2 is of, for example, a solid polymer
electrolyte type and has a stack structure in which plural unit
cells are stacked. The unit cell of the fuel cell 2 has an air
electrode on one surface of the electrolyte formed of an ion
exchange membrane and a fuel electrode on the other surface. The
unit cell has a pair of separators with the air electrode and the
fuel electrode interposed therebetween. The fuel gas is supplied to
a fuel gas flow channel of one separator and the oxidant gas is
supplied to an oxidant gas flow channel of the other separator. The
fuel cell 2 generates electric power with the gas supply.
[0030] The oxidant gas piping system 3 includes a supply passage 11
in which the oxidant gas supplied to the fuel cell 2 flows and a
discharge passage 12 in which oxidant-off gas discharged from the
fuel cell 2 flows. The supply passage 11 is provided with a
compressor 14 blowing in the oxidant gas through a filter 13 and a
humidifier 15 humidifying the oxidant gas pressurized and
transported by the compressor 14. The oxidant-off gas flowing in
the discharge passage 12 passes through a back-pressure control
valve 16, is exchanged in humidity by the humidifier 15, and then
is discharged as waste gas from the system to atmospheric air.
[0031] The fuel gas piping system 4 includes a hydrogen tank 21 as
a fuel source, a supply passage 22 in which the hydrogen gas
supplied from the hydrogen tank 21 to the fuel cell 2 flows, a
circulation passage 23 for returning hydrogen-off gas (fuel-off
gas) discharged from the fuel cell 2 to a merging point A of the
supply passage 22, a pump 24 feeding the hydrogen-off gas in the
circulation passage 23 under pressure to the supply passage 22, and
a discharge passage 25 branched from the circulation passage
23.
[0032] The hydrogen tank 21 is configured to store the hydrogen gas
of 35 MPa or 70 MPa. When a main stop valve 26 for the hydrogen
tank 21 is opened, the hydrogen gas flows in the supply-passage 22.
Thereafter, the hydrogen gas is adjusted in flow rate and pressure
by the injector 29, is reduced in pressure to, for example, 200 kPa
by a pressure reducing valve including a mechanical regulator valve
27, and is then supplied to the fuel cell 2. The main stop valve 26
and the injector 29 are fitted to a valve assembly 30 indicated by
a dotted frame line in FIG. 1 and the valve assembly 30 is
connected to the hydrogen tank 21 (details of which will be
described later).
[0033] A shutoff valve 28 is disposed upstream the merging point A
of the supply passage 22. A circulation system of the hydrogen gas
includes a downstream flow channel downstream the merging point A
of the supply passage 22, a fuel gas flow channel formed in the
separator of the fuel cell 2, and the circulation passage 23, which
sequentially communicate with each other. A purge valve 33 on the
discharge passage 25 is properly opened or closed during the
operation of the fuel cell system 1, whereby impurities in the
hydrogen-off gas is discharged to a hydrogen diluter not shown
along with the hydrogen-off gas. The impurity concentration of the
hydrogen-off gas in the circulation passage 23 is lowered with the
opening of the purge valve 33, and the hydrogen concentration of
the circulating hydrogen-off gas is enhanced.
[0034] The controller 7 is constituted as a micro computer having a
CPU, an ROM, and an RAM therein. The CPU performs desired
calculations in accordance with a control program to perform
various processes or control such as a flow rate control of the
injector 29. The ROM stores a control program or control data to be
processed by the CPU. The RAM is used as various operation areas
for the control process. The controller 7 receives detection
signals of various pressure sensors or temperature sensors used in
gas systems (3, 4) or a coolant system not shown and outputs
control signals to the elements. As described later, the controller
7 serves as a valve controller for controlling the injector 29 by a
duty control.
[0035] FIG. 2 is a sectional view illustrating the periphery of the
injector 29 disposed on the hydrogen tank 21.
[0036] First, the hydrogen tank 21 is described.
[0037] The hydrogen tank 21 includes a tank body 101 forming a body
of the hydrogen tank 21 and having a closed cylindrical shape and a
mouthpiece portion 102 located at an end in the longitudinal
direction of the tank body 101. The inside of the tank body 101
serves as a reservoir space 104 storing the hydrogen gas with a
high pressure. The tank body 2 has a two-layered structure of an
inside resin liner 107 having a gas barrier property and a shell
108 covering the outside of the resin liner 107. The shell 108 is
formed of FRP.
[0038] The mouthpiece portion 102 (mouth portion) is formed of
metal such as stainless and is disposed at the center of one
spherical end wall of the tank body 101. The valve assembly 30 can
be screwed into the mouthpiece portion 102 by the use of an
internal thread formed in the inner circumferential surface of the
mouthpiece portion 102.
[0039] The valve assembly 30 extends to the inside and the outside
of the hydrogen tank 21 and forms a gas discharge section of the
hydrogen tank 21. The valve assembly 30 has, for example, a single
housing 300, and the main stop valve 26 and the injector 29 are
fitted in series to the housing 300. In this embodiment, the main
stop valve 26 is disposed in a first area 301 of the housing 300
inserted into the hydrogen tank 21, and the injector 29 is disposed
in a second area 302 exposed from the hydrogen tank 21. The housing
300 is formed of metal such as SUS or aluminum.
[0040] Although the injector 29 and the main stop valve 26 as chief
elements of the invention are mainly shown in FIG. 2, other valves
such as a safety valve (a relief valve or a fusible plug valve) and
a check valve may be disposed in the housing 300 in addition to the
injector 29 and so on. A filling passage for the hydrogen gas not
shown is usually formed in the housing 300. The housing 300 may be
formed of a single member or a combination of plural members. The
housing 300 is also used as the bodies (bases) of the main stop
valve 26 and the injector 29, but the bodies of the main stop valve
26 and the injector 29 may be formed independently and then the
bodies may be fitted to the housing 300.
[0041] An in-valve flow channel 310 allowing the reservoir space
104 to communicate with the outside supply passage 22 is formed in
the housing 300. The in-valve flow channel 310 includes a first
flow channel 311, a second flow channel 312, and a third channel
313 sequentially from the reservoir space 104. The space between
the first flow channel 311 and the second flow channel 312 is
opened or closed by the main stop valve 26. The second flow channel
312 forms a primary flow channel of the injector 29. The third flow
channel 313 forms a secondary flow channel of the injector 29 and
is connected to the outside supply passage 22.
[0042] The main stop valve 26 (on-off valve) serves as a source
valve for the hydrogen tank 21 and blocks the flow of fluid
(hydrogen gas) from, the hydrogen tank 21 to the supply passage 22.
The main stop valve 26 is constituted as an electromagnetic shutoff
valve. The main stop valve 26 shuts off the in-valve flow channel
310, for example, when a valve rod 321 (mobile) goes in the axial
direction by the excitation of a solenoid and a valve body 322 at
an end of the valve rod 321 comes into contact with a valve seat
323. On the other hand, when the valve rod 321 goes back in the
axial direction by the demagnetization of the solenoid and the
valve body 322 breaks contact with the valve seat 323, the hydrogen
gas is allowed to flow out of the reservoir space 104. The axial
direction X-X of the valve rode 321 and the valve body 322 is equal
to the axial direction of the hydrogen tank 21. The axial direction
of the main stop valve 26 means the movement direction of the valve
body 322 and corresponds to the axial direction X-X of the valve
body 322 in this case.
[0043] The injector 29 is located outside the outer circumferential
surface of the tank body 101 and is electrically connected to the
controller 7. The injector 29 is an electromagnetic on-off valve
that can adjust the flow rate or the pressure of the hydrogen gas
by driving the valve body 401 at a predetermined driving period
using an electromagnetic driving power to move the valve body away
from the valve seat 402. The injector 29 can control the driving
period of the valve body 401 to a high-response region and thus has
higher response property than that of a mechanical pressure
regulating valve.
[0044] The injector 29 has a flow rate adjusting mechanism 290 that
can adjust the flow rate and the pressure of the hydrogen gas to
the secondary side. The flow rate adjusting mechanism 290 roughly
includes a main valve portion 410 and a solenoid portion 420. The
main valve portion 410 and the solenoid portion 420 are disposed in
the second area 302 of the housing 300 and adjust the flow rate of
the hydrogen gas from the hydrogen tank 21 by the duty control.
[0045] The main valve portion 410 includes the valve body 401 and
the valve seat 402. The valve body 401 is of a poppet type and is
formed of metal. The axial direction Y-Y of the valve body 401 is
perpendicular to the axial direction X-X of the hydrogen tank 21.
The axial direction of the injector 26 means the movement direction
of the valve body 401 and corresponds to the axial direction Y-Y of
the valve body 401 in this case.
[0046] The valve seat 402 is formed of an annular resin member
having a seal property and a pressure-resistant property and has an
elastic modulus higher than the housing 300 (base member). The
center of the valve seat 402 is opened and serves as a jet hole 404
jetting the hydrogen gas to the secondary side. The opening area of
the jet hole 404 changes depending on the position of the
valve-body 401 in the axial direction. When the valve body 401
comes into contact with the valve seat 402, the opening area of the
jet hole 404 is zero and the outflow of the hydrogen gas to the
secondary side is prevented. As described above, since the valve
seat 402 has an elastic property, the valve body 401 can be made to
come closely into contact with the valve seat 402, thereby
preventing the outflow of the hydrogen gas to the secondary side
with a high sealing property.
[0047] The solenoid portion 420 can have a variety of basic
structures such as an I plunger type and is for a so-called flat
panel type in this embodiment. Specifically, the solenoid portion
420 includes a coil 421, a core 422, and a plunger 423 having a
flat panel shape formed integrally with the valve body 401. A gap
exists between the core 422 and the plunger 423, and a spring 425
is disposed coaxial (in the Y-Y direction) with the valve body 401.
The spring 425 biases the valve body 401 to the valve seat 402.
[0048] In the injector 29, the coil 421 is electrified, and then
the core 422 is magnetized and attracts the plunger 423 and the
valve body 401. Accordingly, the valve body 401 moves in a
direction in which it gets apart from the valve seat 402 against
the spring 425. On the contrary, when the electrification of the
coil 421 is stopped; that is, when the solenoid portion 420 is
demagnetized, the valve body 401 moves by the spring force of the
spring 425 in a direction in which it gets contact with the valve
seat 402. The current supplied to the coil 421 is pulse-like
excitation current.
[0049] In this way, the injector 29 is configured to change the
opening time (ON time) or the opening area of the jet hole 404 by
two steps, by multiple steps, continuously (by no step), or
linearly, by turning on or off the pulse-like current supplied to
the coil 421. The gas jet time and timing of the jet hole 404 are
controlled by the control signals output from the controller 7,
whereby the injector 29 adjusts the flow rate and the pressure of
the hydrogen gas with high precision. The duty control method of
changing the duty ratio of the pulse-like excitation current is
used as the control method of the injector 29. Here, the duty ratio
is obtained by dividing the ON time of the pulse-like excitation
current by the switching period as the sum of the ON time and the
OFF time of the pulse-like excitation current. By changing the duty
ratio, the injector 29 can adjust a secondary pressure to any
pressure of 0 to a primary pressure (tank inside pressure).
[0050] As shown in FIG. 2, the injector 29 includes a handle
portion 430 adjacent to the solenoid portion 420. A part of the
handle portion 430 is located outside the outer surface of the
housing 300 so as to allow an operator to operate the handle
portion. The axial direction of the handle portion 430 is equal to
the axial direction Y-Y. An external thread 431 is formed in a part
of the outer circumferential surface of the handle portion 430 so
as to be screwed into the housing 300. By detaching the handle
portion 430 from the housing 300, the main valve portion 410 and
the solenoid portion 420 of the injector 29 can be adjusted.
[0051] According to the above-mentioned embodiment, the injector 29
is disposed on the hydrogen tank 21, and it is possible to adjust
the flow rate and the pressure of the hydrogen gas by the use of
the injector 29 when the hydrogen gas is supplied from the hydrogen
tank 21 to the supply passage 22. Accordingly, it is possible to
adjust the flow rate (supply flow rate) of the hydrogen gas from
the hydrogen tank 21 to the fuel cell 2 with higher precision than
that of the case where a mechanical pressure regulating valve is
disposed on the hydrogen tank 21. In addition, since the injector
29 has higher response property than the mechanical pressure
regulating valve, it is possible to supply the fuel cell 2 with the
hydrogen gas at a flow rate based on the electricity generated by
the fuel cell 2, the consumption of the hydrogen gas, or the
operation state.
[0052] The injector 29 can block the discharge of the hydrogen gas
to the secondary side and the injector 29 can be made to serves as
a tank source valve. Particularly, since the hydrogen gas pressure
(tank inside pressure) of the primary side acts on the surface of
the plunger 423 opposed to the core 422 at the time of blocking, a
force in the closing direction acts on the valve body 401 through
the plunger 423. Accordingly, it is possible to enhance the degree
of close contact between the valve body 401 and the valve seat 402
and thus to enhance the blocking property of the flow channel in
the injector 29.
[0053] On the other hand, in this embodiment, the main stop valve
26 as the tank source valve is disposed on the primary side of the
injector 29. Accordingly, by closing the main stop valve 26 when
stopping the fuel cell system 1 (at the time of stop of the
hydrogen gas supply), it is possible to prevent the tank inside
pressure from acting directly on the injector 29. Even when the
blocking property of the injector 29 is deteriorated, it is
possible to block the discharge of the hydrogen gas from the
hydrogen tank 21 by the use of the main stop valve 26, thereby
properly accomplishing fail safe.
[0054] In addition, the following advantages are obtained in view
of arrangement of the injector 29.
[0055] That is, since the injector 29 is disposed outside the
hydrogen tank 21, it is possible to enhance the treatment or repair
property of the injector 29. Since the heat exchange of the
injector 29 with external air is facilitated, it is possible to
suppress the influence of a decrease in temperature of the hydrogen
tank 21 at the time of discharging gas.
[0056] Moreover, since the axial direction Y-Y of the injector 29
is perpendicular to the axial direction X-X of the hydrogen tank
21, it is possible to relatively reduce the total length of the
structure in which the valve assembly 30 is disposed on the
hydrogen tank 21. Accordingly, it is possible to reduce the size as
a whole and to reduce the installation space for the hydrogen tank
21. In view of the limited installation space, the hydrogen tank 21
can be relatively enhanced in the longitudinal direction, thereby
enhancing the storage capacity of the hydrogen gas. The axial
direction Y-Y of the injector 29 may be made to cross the axial
direction X-X of the hydrogen tank 21.
SECOND EMBODIMENT
[0057] Next, an injector 29 (valve) according to a second
embodiment of the invention will be described with reference to
FIG. 3. The second embodiment is different from the first
embodiment, in that the injector 29 of the valve assembly 30 is
coaxial. The same elements as the first embodiment are denoted by
the same reference numerals as the first embodiment and detailed
description thereof is omitted.
[0058] The injector 29 includes a main valve portion 410, a
solenoid portion 420, and a handle portion 430. The portions 410,
420, and 430 are disposed on the first area 301 of the valve
assembly 30 sequentially along the axial direction X-X of the
hydrogen tank 21. That is, in this embodiment, the axial direction
of the injector 29 corresponding to the axial direction of the
valve body 401 is equal to the axial direction X-X of the hydrogen
tank 21.
[0059] An annular flow channel or plural flow channels 451 are
formed through the handle portion 430. The flow channel 451 extends
in the axial direction X-X and communicates with the flow channel
453 in the housing 300. The flow channel 451 extends in the axial
direction X-X so that the hydrogen gas flows in the outer
circumference of the solenoid portion 420, and communicates with a
flow channel 455 on the secondary side of the injector 29. The flow
channel 455 is formed in the housing 300 and communicates with the
supply passage 22. Accordingly, the hydrogen gas in the reservoir
space 104 flows sequentially through the flow channel 451, the flow
channel 453, the jet hole 404, and the flow channel 455 in the
injector 29 and then flows to the supply passage 22.
[0060] The second embodiment is more advantageous than the first
embodiment, in that the injector 29 can easily make itself clean
due to the injector 29 disposed coaxial with the hydrogen tank
21.
[0061] Specifically, contamination such as abrasion dust generated
at the time of movement of the valve body 401 in the axial
direction can be discharged to the flow channel 455 along with the
hydrogen gas flowing in the flow channel 453. Accordingly, the
contamination does not stay around the solenoid portion 420 of the
injector 29 and thus the injector 29 can make itself clean with a
simple structure. The self cleaning effect is advantageous
particularly when the outer circumferential surface of the plunger
423 or the outer circumferential surface of the valve body 401
slides on the inside wall of the housing 300. Note that FIG. 3 does
not show the state where the outer circumferential surface of the
plunger 423 or the outer circumferential surface of the valve body
401 slides.
[0062] In a modified example of this embodiment, the axial
direction of the injector 29 may not be matched with the axial
direction X-X of the hydrogen tank 21 and, for example, both
directions may be parallel to each other. In this case, the
above-mentioned advantages can be obtained. Note that although the
main stop valve 26 has been omitted from the valve assembly 30, the
main stop valve 26 may be disposed on the primary side of the
injector 29.
[0063] The injectors 29 described in the first and second
embodiments can be considered as a pressure regulating valve
(pressure reducing valve, regulator), since the gas pressure to the
secondary side can be adjusted.
INDUSTRIAL APPLICABILITY
[0064] The above-mentioned fuel cell system 1 according to the
invention can be mounted on a two-wheel or four-wheel vehicle, a
train, an air plane, a ship, a robot, and other mobile bodies. The
fuel cell system 1 may be stationary, or may be built in a
cogeneration system. In addition, the tank having the injector 29
disposed thereon may be a hydrogen storing alloy tank or may store
other hydrocarbon fuel gas. For example, the tank may store
compressed natural gas, for example, by 20 MPa, and the kind of the
stored fluid is not limited to gas or liquid.
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