(19)
(11)EP 2 971 509 B1

(12)EUROPEAN PATENT SPECIFICATION

(45)Mention of the grant of the patent:
06.05.2020 Bulletin 2020/19

(21)Application number: 14769967.2

(22)Date of filing:  11.03.2014
(51)Int. Cl.: 
H01M 8/04089  (2016.01)
G05D 16/06  (2006.01)
(86)International application number:
PCT/US2014/023333
(87)International publication number:
WO 2014/150467 (25.09.2014 Gazette  2014/39)

(54)

FLUIDIC COMPONENTS SUITABLE FOR FUEL CELL SYSTEMS INCLUDING PRESSURE REGULATORS AND VALVES

FLUIDISCHE KOMPONENTEN FÜR BRENNSTOFFZELLENSYSTEME MIT DRUCKREGLERN UND VENTILEN

COMPOSANTS FLUIDIQUES APPROPRIÉS POUR DES SYSTÈMES DE PILE À COMBUSTIBLE COMPRENANT DES RÉGULATEURS DE PRESSION ET DES SOUPAPES


(84)Designated Contracting States:
AL AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HR HU IE IS IT LI LT LU LV MC MK MT NL NO PL PT RO RS SE SI SK SM TR

(30)Priority: 15.03.2013 US 201313832528

(43)Date of publication of application:
20.01.2016 Bulletin 2016/03

(73)Proprietor: Intelligent Energy Limited
Loughborough LE11 3GB (GB)

(72)Inventors:
  • CURELLO, Andrew, J.
    Hamden, CT 06518 (US)
  • SPAHR, Paul
    Durham, CT 06422 (US)
  • RATH, Kurt
    F-95220 Herblay (FR)

(74)Representative: Creation IP Ltd 
Hillington Park Innovation Centre 1 Ainslie Road
Glasgow G52 4RU
Glasgow G52 4RU (GB)


(56)References cited: : 
WO-A2-2008/097849
US-A- 1 132 424
US-A- 1 762 260
US-A- 3 056 280
US-A- 3 525 355
US-A- 593 091
US-A- 1 132 424
US-A- 1 762 260
US-A- 3 525 355
US-A- 5 345 963
  
      
    Note: Within nine months from the publication of the mention of the grant of the European patent, any person may give notice to the European Patent Office of opposition to the European patent granted. Notice of opposition shall be filed in a written reasoned statement. It shall not be deemed to have been filed until the opposition fee has been paid. (Art. 99(1) European Patent Convention).


    Description

    FIELD OF THE INVENTION



    [0001] This invention generally relates to fluidic components that connect fuel cartridges to various fuel cell systems and fuel refilling devices. Particularly, this invention relates to pressure regulators that take fuel at a relatively high pressure from the fuel cartridges and regulate the output pressure to levels that are acceptable to fuel cells and fuel refilling devices. More specifically, the present invention relates to adjustable pressure regulators and pressure regulators with an inlet restrictor or with a by-pass and semi-automatic valves, among others.

    BACKGROUND OF THE INVENTION



    [0002] Fuel cells are devices that directly convert chemical energy of reactants, i.e., fuel and oxidant, into direct current (DC) electricity. In general, fuel cell technology includes a variety of different fuel cells, such as alkali fuel cells, polymer electrolyte fuel cells, phosphoric acid fuel cells, molten carbonate fuel cells, solid oxide fuel cells and enzyme fuel cells. Fuel cells generally run on hydrogen (H2) fuel, and they can also consume non pure hydrogen fuel. Non pure hydrogen fuel cells include direct oxidation fuel cells, such as direct methanol fuel cells (DMFC), which use methanol, or solid oxide fuel cells (SOFC), which use hydrocarbon at high temperature. Hydrogen fuel can be stored in compressed form or within compounds such as alcohols or hydrocarbons or other hydrogen containing materials that can be reformed or converted into hydrogen fuel and byproducts. Hydrogen can also be stored in chemical hydrides, such as sodium borohydride (NaBH4), that react with water or an alcohol to produce hydrogen and byproducts. Hydrogen can also be adsorbed or absorbed in metal hydrides, such as lanthanum pentanickel (LaNi5) at a first pressure and temperature and released to fuel a fuel cell at a second pressure and temperature.

    [0003] Most hydrogen fuel cells have a proton exchange membrane or polymer electrolyte membrane (PEM), which allows the hydrogen's protons to pass through but forces the electrons to pass through an external circuit, which advantageously can be a cell phone, a personal digital assistant (PDA), a computer, a power tool or any device that uses electron flow or electrical current. The fuel cell reaction can be represented as follows:

    Half-reaction at the anode of the fuel cell:
    H2 → 2H+ + 2e-

    Half-reaction at the cathode of the fuel cell:
    2(2H+ + 2e-) + O2 → 2H2O



    [0004] Generally, the PEM is made from a polymer, such as Nafion® available from DuPont, which is a perfluorinated sulfonic acid polymer having a thickness in the range of about 0.05 mm to about 0.50 mm, or other suitable membranes. The anode is typically made from a Teflonized carbon paper support with a thin layer of catalyst, such as platinum-ruthenium, deposited thereon. The cathode is typically a gas diffusion electrode in which platinum particles are bonded to one side of the membrane.

    [0005] For DMFC, the chemical-electrical reaction at each electrode and the overall reaction for a direct methanol fuel cell are described as follows:

    Half-reaction at the anode:
    CH5OH + H2O → CO2 + 6H+ + 6e-

    Half-reaction at the cathode:
    1.5O2 + 6H+ + 6e- → 3H2O

    The overall fuel cell reaction:
    CH3OH + 1.5O2 → CO2 + 2H2O

    DMFCs are discussed in U.S. Patent Nos. 4,390,603 and 4,828,941.

    [0006] In a chemical metal hydride fuel cell, potassium or sodium borohydride is reformed and reacts as follows:
    NaBH4 + 2H2O → (heat and/or catalyst) → 4(H2) + (NaBO2) Suitable catalysts for this reaction include platinum and ruthenium, and other metals. The hydrogen fuel produced from reforming sodium borohydride is reacted in the fuel cell with an oxidant, such as O2, to create electricity (or a flow of electrons) and water by-product, illustrated above. Sodium borate (NaBO2) by-product is also produced by the reforming process. A sodium borohydride fuel cell is discussed in U.S. Patent No. 4,261,956.

    [0007] Pressure regulators and other fluidic flow control devices are needed to control or regulate the flow of fuel from fuel cartridges or fuel storages to fuel cell systems, fuel refilling devices and the devices that fuel cells powered. The known art discloses various pressure regulators and flow control devices. A need, however, exists for improved pressure regulators and flow control devices. To a certain extent, this need has been addressed by commonly owned U.S. patent no. 8,002,853 and its progenies, U.S. published patent application nos. 2010/0104481, 2011/0189574 and 2011/0212374. US 1762260 describes a constant ratio pressure reducing valve with a high pressure diaphragm and a low pressure diaphragm, which operates in response to the differential pressure on these diaphragms. A valve member is moved against and away from a seat by the diaphragms. The working areas of the diaphragms may be in any ratio desired to achieve a desired constant ratio pressure reduction. US 3525355 describes flow control apparatus having an external bleed path and an internal bleed path and wherein a main stream of flow is controlled in response to the pressure of the flow in the internal bleed path which flow is controlled in response to the pressure of the flow in the external bleed path. US 1132424 describes in a reducing valve, the combination of recessed rings fitting telescopically inside one another, lever supporting said rings, shoulders on said rings engaging the recesses in the adjacent rings, to lock said rings together when in the extreme downward position and prevent them from blowing out in case the supporting levers should break, and a valve spindle to which said levers are coupled. WO 2008/097849 A2 describes a hydrogen generator comprising a first fuel chamber containing a viscous fuel component, a second fuel chamber containing a metal hydride fuel component, wherein the viscous fuel component reacts with the metal hydride fuel component to produce hydrogen, wherein the hydrogen generator measures, transports or stores a single dose of the viscous fuel component when an internal hydrogen pressure of the hydrogen generator is higher than a first predetermined pressure, and transports said single dose to react with the metal hydride fuel component when said internal pressure is lower than a second predetermined pressure.

    SUMMARY OF THE INVENTION



    [0008] The invention provides a pressure regulator in accordance with the appended claims. The present disclosure describes adjustable pressure regulators comprising a movable shuttle disposed between a high pressure diaphragm and a low pressure diaphragm, a shuttle housing to house the shuttle, and a conduit connecting an inlet to an outlet. The high pressure diaphragm is located proximate to the inlet, and the low pressure diaphragm is located proximate to the outlet. The pressure regulator further comprises a movable member connected to the shuttle housing, wherein said movable member is movable to contact the low pressure diaphragm, to determine an area of the contacted diaphragm that can flex; or said movable member is movable to contact the high pressure diaphragm, to determine an area of the contacted diaphragm that can flex, the movable member has a shape of a circular ring. The movable member is adjustable to change an outlet pressure ofthe pressure regulator.

    [0009] The present disclosure also describes pressure regulators with an inlet restrictor that allows incoming fluid to enter the pressure regulators when the pressure ofthe incoming fluid is higher than a threshold level. The present disclosure also describes positioning the inlet restrictor at another location to prevent a partial vacuum from forming inside a pressure regulator.

    [0010] The present disclosure further describes a semi-automatic valve that is opened manually but closes automatically when fluid flowing through the valve is insufficient to keep the valve open. The semi-automatic valve can also be a semi-automatic electrical switch.

    [0011] The present disclosure further describes a pressure regulator with a by-pass valve, which directs the flow to bypass the pressure regulator, when the flow is slow or has low pressure.

    BRIEF DESCRIPTION OF THE DRAWINGS



    [0012] In the accompanying drawings, which form a part of the specification and are to be read in conjunction therewith and in which like reference numerals are used to indicate like parts in the various views:

    Figure 1A is a cross-sectional view and Figure 1B is an exploded view illustrating the operating principles of a conventional pressure regulator shown and described in US 2010/0104481;

    Figure 2A is a cross-sectional view and Figures 2b-2C are top views of an exemplary adjustable pressure regulator;

    Figures 3A-3B are cross-sectional view of an adjustable pressure regulator of the present invention;

    Figure 4 is a cross-sectional view of an adjustable piston or shuttle in another adjustable pressure regulator of the present invention;

    Figures 5A-5B are cross-sectional view of another adjustable pressure regulator of the present invention;

    Figures 6A-6B are cross-sectional view of another adjustable pressure regulator of the present invention;

    Figures 7A-7B are cross-sectional view of another exemplary adjustable pressure regulator;

    Figures 8A-8B are cross-sectional view of another adjustable pressure regulator of the present invention;

    Figures 9A-9B are cross-sectional view of pressure regulators with an inlet restrictor of the present invention;

    Figure 10A is cross-sectional view of a pressure regulator with an inlet restrictor of the present invention; Figure 10B is a cross-sectional view of another inlet restrictor;

    Figures 11A is a cross-sectional view of a pressure regulator with a vent to prevent partial vacuum of the present invention; Figure 11B is a cross-sectional view of another vent;

    Figures 12A-12B are cross-sectional views of a semi-automatic valve of the present invention;

    Figures 13A-13B are cross-sectional views of another semi-automatic valve of the present invention; Figures 13C-13D are cross-sectional views of the semi-automatic valve of Figures 13A and 13B operatively connected to an electrical switch;

    Figures 14A-14B are cross-sectional views of a pressure regulator with a by-pass valve of the present invention; and

    Figures 15A-15C illustrate a pressure regulator with a temperature shut-off component.


    DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS



    [0013] As illustrated in the accompanying drawings and discussed in detail below, the present invention is directed to fluidic components and fluid flow control components that are used in fuel cell systems with fuel cells, interface systems and fuel cartridges or fuel tanks/storages. These components can also be used in or with other technologies and industries and are not limited to fuel cell systems.

    [0014] Fuel cell fuels include any fuel that can be used with any fuel cells and can be solid, liquid and gaseous fuels or combinations thereof. Liquid fuels include methanol, water, methanol/water mixture, methanol/water mixtures of varying concentrations, pure methanol, and/or methyl clathrates, ethanol or other alcohols. Solid reactive fuel cell fuels include chemical metal hydrides, such as sodium borohydrides, potassium borohydrides and other metal hydrides that react with a liquid or gel to produce hydrogen. Solid fuels can also include metal hydrides that absorb and adsorb hydrogen within the hydride's matrix at a certain temperature and pressure and release hydrogen to fuel the fuel cells at another temperature and pressure. Suitable metal hydrides, including but not limited to lanthanum pentanickel (LaNi5) and the metal hydrides disclosed in U.S. Pat. Appl. Pub. No. US 2009/0060833.

    [0015] Fuels can further include hydrocarbon fuels, which include, but are not limited to, butane, kerosene, alcohol, and natural gas, as set forth in U.S. Pat. Appl. Pub. No. US 2003/0096 150, entitled "Liquid Hereto-Interface Fuel Cell Device," published on May 22, 2003. Fuels can also include liquid oxidants that react with fuels and liquid electrolyte. The present invention is therefore not limited to any type of fuels, activators, electrolytic solutions, oxidant solutions or liquids or solids contained in the supply or otherwise used by the fuel cell system. The term "fuel" as used herein includes all fuels that can be reacted in fuel cells or stored in the fuel supply, and includes, but is not limited to, all of the above suitable fuels, electrolytic solutions, oxidant solutions, gaseous, liquids, solids, and/or chemicals including additives and catalysts and mixtures thereof.

    [0016] Conventional fluidic control components such as conventional pressure regulators are described in a plurality of sources. One example of pressure regulators, discussed as Figures 18A-B in commonly owned US 2010/0104481, is illustrated in Figures 1A-1B to discuss the principles of operations of pressure regulators.

    [0017] One application for such a pressure regulator is to reduce the pressure of the hydrogen exiting a hydrogen storage or a hydrogen generator. Such a regulator can be positioned downstream or upstream of a shut-off valve of a hydrogen storage or generator, and can be positioned adjacent therewith. An exemplary pressure regulator 164 is illustrated in FIGS. 1A-1B. Regulator 164 comprises inlet housing 166, outlet housing 168 and retainer 170 disposed therebetween. Movably disposed within retainer or shuttle housing 170 is shuttle 172. A first diaphragm 174 is clamped between inlet housing 166 and shuttle housing 170 and a second diaphragm 176 is clamped between outlet housing 168 and shuttle housing 170. Inlet housing 166 defines inlet channel 178 and outlet housing 168 defines outlet channel 180. The interior of retainer or shuttle housing 170, where shuttle 172 is housed, can be and is preferably exposed to a reference pressure, which may be atmospheric pressure. An optional ball 182 can be provided below first diaphragm 174 directly below inlet channel 178 to help seal the inlet channel. Ball 182 can be used with any of the pressure regulators described herein. As shown, first diaphragm 174 is exposed to the inlet pressure and second diaphragm 176 is exposed to the outlet pressure. Shuttle housing 170 is preferably in fluid communication with a reference pressure, Pref, such as atmospheric pressure.

    [0018] Since the applied forces on shuttle 172 are the products of the applied pressure times the area exposed to that pressure, the forces acting on shuttle 172 can be summarized as follows:

    The inlet diaphragm forces are:

    The outlet diaphragm forces are:



    [0019] Since the force on the upper surface equals the force on the lower surface, the shuttle force is the same in both equations. Solving both equations for shuttle force and equating them:



    [0020] This equation can be rewritten to:



    [0021] For the case where the reference pressure is 0 psi relative or 1 atmosphere:



    [0022] For the case where the reference pressure is not 0 psi relative, both sides of the shuttle are influenced by the reference pressure relative to their respective areas. Before the outlet pressure rises enough to shut off the inlet, the inlet area is equal to the upper surface of the shuttle. After the outlet pressure rises enough to shut off the inlet the inlet area shrinks to the small inlet opening. After the inlet area decreases, it takes less pressure in the low pressure section to keep the inlet closed. This feature will reduce shuttle oscillation with slight outlet pressure drops.

    [0023] When the outlet force is less than the inlet force, the inlet hydrogen pressure forces first membrane downward to open a flow path from inlet channel 178 to inner circular channel 184, which is connected to top lateral channel 186, which is connected to outer circular channel 188 and to connecting channel 190, which is connected to lower lateral channel 192 and to outlet channel 180. Advantageously, outlet channel 180 is enlarged at 194 to allow the hydrogen gas to expand and to lose some additional pressure before exiting. Outlet channel 180 is also enlarged so that regulator 164 can be fitted to the other component(s) of the fuel cell system. Lateral channels 186 and 192 are sealed by a ball as shown in Figure 1A.

    [0024] While all the structural or functional features of pressure regulator 164 may not be utilized in the embodiments described below, the principles of pressure regulators are demonstrated.

    [0025] Disclosed herein is an ability to adjust the outlet pressure on demand or without having to disassemble the pressure regulator. Referring to Figure 2A-2C, pressure regulator 200 has adjustable piston or shuttle 202 that has a fixed, smaller high pressure head 204 connected by stem 206 to variable larger low pressure head 208. Low pressure head 208 comprises a center portion 210 and a plurality of concentric rings 212n. As shown in Figure 2A, concentric rings have a reverse Z-shape in cross-section and are positioned on the second or low pressure diaphragm 176. Within shuttle housing 170, which is preferably exposed to a reference pressure such as atmospheric pressure, at least one retractable adjustment arm 214 is positioned. Arm 214 is positioned directly above concentric rings 212 to prevent the rings from moving along with low pressure diaphragm 176. As specifically shown in Figure 2A, arms 214 would prevent all the rings from moving with low pressure diaphragm 176. As shown in Equation 5 above, the outlet pressure is proportional to the ratio of the area of the high pressure head 204 and the area of the center portion 208 of the low pressure head 208. Arms 214 can be linearly retractable, as shown in Figure 2B, pivotally retractable, as shown in Figure 2C. Arm 214 can be a shutter similar to those used in cameras.

    [0026] One of ordinary skill in the art would readily recognize that as arms 214 retract more concentric rings 214 become movable with the shuttle 202 to enlarge the effective area of the outlet to lower the outlet pressure. Moving arms 214 in the opposite direction, i.e., into the shuttle housing 170 would have the opposite effect. Moving arms 214 preferably partially extend outside of shuttle housing 170 so that a user has access to them to adjust the pressure regulator. The reverse Z-shape of concentric rings 214 is selected to ensure that center portion 208 and unobstructed ring(s) 214 can freely move, while ring(s) 214 that are obstructed by arms 214 are held relatively stationary between obstructing arms 214 and low pressure diaphragm 176. Other shapes, such as reverse S-shape, upside down truncated conical shape can be used.

    [0027] Figures 3A and 3B illustrate an embodiment of the inventive variable pressure regulator. In this embodiment, pressure regulator 200 has a variable low pressure diaphragm 176. As shown, this embodiment has fixed movable shuttle or piston 172 positioned between high pressure diaphragm 174 and low pressure diaphragm 176. Shuttle housing 170, illustrated in Figure 3A as being exposed to a Pref such as atmospheric pressure, also has movable arm 216, which can selectively come into contact with low pressure diaphragm 176. When arm 216 contacts low pressure diaphragm 176, it limits the surface area of diaphragm 176 that can flex due to the outlet pressure as shown in Figure 3B, thereby tending to raise the outlet pressure. Arm 216 can have any shape and in accordance with the invention has the shape of a circular ring mounted on the inside of shuttle housing 170 and is movable in the direction of the arrow 218 shown in Figure 3B to selectively come into contact with low pressure diaphragm 176.

    [0028] In another embodiment, movable shuttle or piston 176 is adjustable as best shown in Figure 4. Shuttle 176 has stem 220 that is re-movably attached to shuttle base 222, for example, stem 200 can be threaded or press-fitted to base 222, which has the larger outlet end of the shuttle. Stem 220 can also be fixedly attached to shuttle base 222 by adhesive after a total length of shuttle 176 has been determined. Adjusting the total length of the piston or shuttle has the effect of pre-stressing or preloading the diaphragms and the pressure regulator. In one example, when the preloading amount is higher than the outlet pressure at outlet 180 and lower than inlet 178, the outlet pressure of the pressure regulator would increase. In another example, when the preloading amount is higher than the inlet pressure, the pressure regulator would be in the shut-off position.

    [0029] In another embodiment, pressure regulator 200 is adjusted by adjusting connector or connecting conduit 190 that fluidly connects the high pressure diaphragm 174 or the high pressure side to the low pressure diaphragm 176 or the low pressure side of the pressure regulator. Referring to Figure 5A, a variable flow restrictor 224 is placed on connecting channel 190 to restrict the flow of fluid therethrough. By restricting or reducing flow through connecting channel 190, the outlet pressure would be lower, and increasing the flow through connecting channel 190 would increase the outlet pressure. Of course, when there is no or substantially no flow through pressure regulator 200, flow restrictor 224 would have no or minimal effect on the pressure regulator.

    [0030] In a variation of the embodiment in Figure 5A, the flow restrictor 224 is not located between the high pressure side and the low pressure side, but is between the outlet 180 or the low pressure side proximate to low pressure diaphragm 176 and fluid port 181 connecting the pressure regulator to a receiver or a fuel consumer such as a fuel cell, as shown in Figure 5B. Reducing the flow would slow the shutting off of pressure regulator 200 resulting in higher dynamic flow pressure at outlet 180.

    [0031] Restricting the flow reduces the speed that the shut-off pressure would reach the low pressure chamber 177 below the large low-pressure diaphragm 176. A volume of fluid or gas is present in chamber 177, and the shut-off pressure would need to propagate through chamber 177 before the entire chamber 177, as well as low-pressure diaphragm 176, reaches the necessary shut-off pressure. Reducing the flow into the chamber 177 increases the amount of time required to bring the volume of fluid or gas in the chamber to the shut-off pressure. Compared to a regulator without any flow restriction in channel 190, the pressure regulator shown in Figure 5A will come up to pressure more slowly because the flow to the low pressure chamber 177 and the low pressure outlet are restricted.

    [0032] Compared to a regulator without any flow restriction in channel 190, the pressure regulator shown in Figure 5B will come up to pressure more quickly, because the flow to the low pressure chamber 177 is restricted, but the low pressure outlet 181 is supplied without restriction. The flow would favor the unrestricted path of outlet 181. Depending on the conditions, the outlet pressure may even overshoot until the restricted chamber 177 reaches the shut-off pressure. The outlet 181 of Figure 5B would reach shut-off pressure faster than an unrestricted regulator that must use fluid flow to fill the low pressure chamber 177 before reaching outlet line 180. Reaching pressure quicker and overshooting the set pressure (if set up) will lead to a quicker start.

    [0033] The embodiment shown in Figures 6A and 6B illustrates another adjusting feature of the present invention. As shown, shuttle housing 170's length is adjustable. Shuttle housing 170 comprises inlet half 166 and outlet half 168 and telescopically connected to each other, such that the length of shuttle housing 170's length is adjustable. The two halves can be connected by matching threads or held together by screws or set screws. A longer length of the shuttle housing 170 can cause a higher outlet pressure. This embodiment is similar to the embodiment shown in Figure 4.

    [0034] The example shown in Figures 7A and 7B is similar to that shown in Figures 2A and 2B, except that the concentric rings 212n are disposed between the high pressure diaphragm 174 and retractable arms 214 to limit the amount of area of diaphragm 174 that is subject to be flexed by the high pressure from inlet 178. For example, more of diaphragm 174 shown in Figure 7B can flex than the diaphragm shown in Figure 7A, because fewer concentric rings 212 are available to obstruct diaphragm 174. The configuration of Figure 7A
    where less of the high pressure diaphragm 174 is exposed causes a lower output pressure than the configuration in Figure 7B where more of the high pressure diaphragm 174 is exposed.

    [0035] The embodiment ofFigures 8A and 8B is similar to that ofFigures 3A and 3B, except that movable arm 216 is selectively contacting high pressure diaphragm 174 to limit the amount of diaphragm 174 that can flex. Similarly, movable arm 216 is preferably a ring that is disposed within shuttle housing 170 and is movable in the direction 218. The effects of movable arm 216 on high pressure diaphragm 174 are similar to those described in connection with the example of Figures 7A and 7B.

    [0036] Another aspect ofthe present inventionrelates to a low pressure restrictive or cut-off device 236 for any pressure regulator 238, including pressure regulators 164 and 200 discussed herein or any known pressure regulator. Restrictive device 236 sets a minimum threshold pressure that pressure regulator 238 would function. When the inlet pressure of the incoming fluid at inlet 178 is less than this minimum threshold pressure, restrictive device 236 remains closed and the incoming fluid would not enter pressure regulator 238. When the inlet pressure is higher than the minimum threshold pressure, restrictive device 236 opens to allow the incoming fluid to enter pressure regulator 238.

    [0037] Referring to Figure 9A, restrictive device 236 comprises a cap 240 biased by spring 242 against high pressure membrane 174, such that high pressure membrane 174 would not flex to allow the incoming fluid to enter the pressure regulator, until the incoming fluid can overcome restrictive device 236. More specifically, cap 240 and spring 242 of restrictive device 236 exerts a limiting pressure (Plim) equals to the spring force exerted by spring 240 divided by the area of cap 240. This limiting pressure is applied to high pressure diaphragm 174 and inlet 178. Incoming fluid with a pressure higher than this limiting pressure would push cap 240 and spring 242 inward to enter pressure regulator 238. One advantage of the embodiment in Figure 9A is that spring 242 and cap 240 are isolated from the fuel cell fuels, such as hydrogen, which can corrode or otherwise negatively affect these components. Although, shuttle housing 170 can be exposed to a reference pressure, as shown in Figure 9A, shuttle housing 170 may be sealed. Any gas that is trapped in shuttle housing 170 acts like a gas spring resisting compression similar to spring 242.

    [0038] In another embodiment, restrictive device 236 comprises a pre-loaded or pre-stressed high pressure diaphragm 174' as shown in Figure 9B, such that an inlet pressure greater than Plim is necessary to open pressure regulator 238. Here, Plim is the amount of pre-loading on high pressure diaphragm 174. The pre-loading can be any protrusion 244 that stretches diaphragm 174'.

    [0039] Figures 10A and 10B illustrate another embodiment of restrictive device 236. In this embodiment, restrictive device 236 comprises a relief valve 246, or a valve 246 that opens after pressure reaches a threshold level or Plim. Shown in Figure 10A, valve 246 comprises an elastomeric disk 248, which is the sealing member that is biased against post 250. Post 250 is attached to base 252 that defines inlet(s) 178. Valve 246 is normally closed when the inlet pressure is below the threshold level or below Plim. Above Plim, sealing member 248 moves away from post 250 to allow incoming fluid to enter pressure regulator 238.

    [0040] Figure 10B shows another embodiment of valve 246. In this configuration, valve 246 comprises an elastomeric member 254 attached to base 252, which defines inlet(s) 178. Elastomeric member 254 has sealing end 256, stem 258 and anchor end 260. Anchor end 260 preferably protrudes from base 252 and has shoulder 262 to anchor member 254 to base 252. Stem 258 extends through base 252 and is connected to sealing member 256. Sealing member 256 covers inlet(s) 178 and seals against base 252 to prevent the transport of incoming fluid with pressure less than Plim. As shown, sealing member 256 has a concave shape. The shape and thickness of sealing member 256 determines the open threshold pressure or Plim. Alternatively, sealing member 256 can have a substantially flat shape. Valve 246 can be any valve that is designed to open at or above a threshold pressure or Plim. Another example of valve 246 is a ball valve or poppet valve shown in Figure 11A.

    [0041] Figure 11A illustrates another aspect of the present invention. Similar to Figures 10A and 10B, this embodiment comprises pressure regulator 238 and valve 246, which preferably is a relief valve. However, valve 246 is located downstream of high pressure diaphragm 174 and is in fluid communication with low pressure diaphragm 176 and low outlet pressure at outlet 180. Valve 246 also vents to atmosphere or another pressure source. In the event that the outlet pressure at outlet 180 or the pressure within the pressure regulator becomes a partial vacuum, i.e., having a pressure below atmospheric pressure, valve 246 opens to allow air to enter pressure regulator to break the partial vacuum. A partial vacuum may occur when a vacuum is used at inlet 178 to close the pressure regulator, and the outlet 180 is at a partial vacuum. As shown in Figure 11B, a different valve 246, such as the one shown in Figure 10A as well as the valve 246 shown in Figure 10B, can also be used.

    [0042] Additionally, pressure regulator 238 can resist the formation of a partial vacuum when shuttle 172 are fixedly attached to low pressure diaphragm 176 and to high pressure diaphragm 174, so that the flexibility or springiness property of both diaphragms and the mass of shuttle 172 are used to resist a partial vacuum on the low pressure side of pressure regulator 238. Shuttle 172 and diaphragms 174 and 176 move in unison, similar to those shown in Figures 13A-B albeit for a different fluidic device. Preferably, shuttle 172 and diaphragm 174 and 176 are permanently attached to each other or are made integral to each other.

    [0043] Pressure regulators can also be modified to be a valve that is opened manually but is shut-off automatically when the flow through the valve drops below a certain threshold. As shown in Figures 12A and 12B, semi-automatic valve 264 has shuttle 266 that traverses chamber 268 and connects to diaphragm 270 supported or biased by spring 272. Valve 264 has inlet 278 and outlet 280, and preferably the chamber that houses spring 272 is exposed to Pref, which can be atmospheric pressure. Shuttle 266 has a reduced central portion 274 and in the closed position seals chamber 268 by sealing members 276, 277, as shown in Figure 12A. In the closed position, incoming fluid cannot enter inlet 278 regardless of its pressure, because chamber 268 is sealed to shuttle 266, and the incoming fluid is not in fluid communication with diaphragm 270.

    [0044] To open valve 264, a user pushes shuttle 266 at its free end toward diaphragm 270 until the reduced central portion 274 is located opposed to inner sealing member 276 while shuttle 266 remains sealed to outer sealing member 277. This brings chamber 268 and inlet 278 into fluid communication with outlet 280 allowing incoming fluid to flow through valve 264, as shown in Figure 12B. As long as the flow though valve 264 remains high or above a preset or predetermined threshold level to overcome the biasing force of spring 272 and of diaphragm 270, the valve remains open. Hence, the force or pressure necessary to keep valve 264 open is determined by the biasing force of spring 272 and diaphragm 270 and the area of diaphragm 270. When the pressure of the flow through valve 264 drops below this threshold level, valve 264 automatically shuts-off due to the actions of spring 272 and diaphragm 270.

    [0045] Another version of semi-automatic valve 264 is shown in Figures 13A-13B. In this embodiment, spring 272 is omitted and the biasing force to keep valve 264 open is provided by diaphragm 270 and optionally by second diaphragm 282. Stem 266 is also simplified. It is sealed to the body of the valve by second diaphragm 282 and seals chamber 268 by an inner sealing seat 284, as shown in Figure 13A.

    [0046] This embodiment of valve 264 operates substantially the same way as that shown in Figures 12A-B. The user pushes stem 266 toward diaphragm 270 allowing chamber 268 and inlet 278 to be in fluid communication with outlet 280. As long as the flow though valve 264 remains high or above a preset or predetermined threshold level to overcome the biasing force of diaphragm 270, the valve remains open. In this embodiment this threshold level is determined by the flexibility or spring-constant and area of diaphragms 270 and 282.

    [0047] Valve 264 shown in Figures 13A-B can also be used as electrical switches that are manually turned on, but are automatically turned off as the flow through valve 264 decreases below the threshold level. Referring to Figures 13C-D, an electrical switch having terminals 286 and 288, one of which is positive and one is negative, positioned in proximity to valve 264 and more specifically to the distal end of stem 266. As shown in Figure 13C, when valve 264 is closed, terminals 286 and 288 are not connected and the electrical circuit connected to these terminals is open and not operational. As shown in Figure 13D, when valve 264 is open, terminals 286 and 288 are connected and the electrical circuit connected to these terminals is closed and operational. Terminals 286 and 288 can be used as a switch for a fuel cell circuit or for a circuit in an electronic device that the fuel cell powers, so that the fuel cell or the electronic device is turned off when the flow of fuel through valve 264 ceases. Terminals 286 and 288 can be biased apart by an insulated spring (not shown) or they may be cantilever beams.

    [0048] Pressure regulators, including but not limited to pressure regulator 238 which includes pressure regulators 164 and 200 discussed herein, can be used with a by-pass valve 290 as shown in Figures 14A and 14B. Incoming fluid enters regulator 238/by-pass valve 290 at inlet 178. When the pressure ofthe incoming fluid is below the "cracking" pressure of pressure regulator 238, i.e., the incoming fluid's pressure is too low to move the diaphragms and piston/shuttle ofthe pressure regulator to open the pressure regulator, the incoming fluid flows to by-pass conduit 292 and through by-pass valve 290 to by-pass outlet 294 and out through outlet 180, as shown in Figure 14A.

    [0049] On the other hand, when the incoming fluid's pressure is sufficiently high, such that the incoming fluid, e.g., fuel cell fuel, should be regulated to be acceptable to the fuel cell, the incoming fluid flows through regulator conduit 296 and pressure regulator 238 and exits through outlet 180. High pressure ofthe incoming fluid pushes diaphragm 298 which pulls valve stem 300 and valve seat 302 into a sealing position with sealing surface 304 of by-pass valve 290. By-pass valve 290 is normally open, and the threshold force that closes the valve and by-pass conduit 292 depends on the spring force and area of diaphragm 298. Countering this threshold force is the force which equals to the product of the incoming fluid's pressure times the effective bottom area ofvalve seat 302. When the force ofthe incoming fluid is less than this threshold force, valve 290 opens to allow the incoming fluid to by-pass pressure regulator 238.

    [0050] In another example, pressure regulator 238, which can by any pressure regulator as discussed above, can be rendered inoperative, e.g., shut-off, when the temperature ofthe fuel cell or the electronic device that the fuel cell powers reaches a certain level where it is desirable to shut the device or the fuel cell down. As a best shown in Figure 15A-C, a material that changes its shape at a certain temperature can be placed within the pressure regulator so that when expanded or changed the material arrests the movements of shuttle 172 or to push shuttle 172 towards inlet 178 or outlet 180 to seal the inlet/outlet. This material can be place in area 306 between outlet 180 and low pressure diaphragm 176, or in area 308 between inlet 178 and high pressure diaphragm 174 or in area 310 between shuttle 172 and shuttle housing 170. Suitable temperature sensitive materials include but are not limited to shape memory alloy (SMA) such as nitinol, as illustrated in Figure 15B. When relax or at lower temperature, SMA can be relatively flat, e.g., wire 312 or wire 314, and can change to a thicker wire, e.g., wire 314 or wire 316, respectively. One or more such SMA wires can be placed in areas 306, 308 or 310 to freeze or render pressure regulator 238 inoperative, at least temporarily until the temperature decreases again.

    [0051] Temperature sensitive material can be an elastomeric or flexible pouch or container storing a liquid that changes from liquid to gas at certain temperature. As illustrated in Figure 15C, container 318, which has a relatively smaller volume when containing a liquid, expands, when the temperature elevates above the boiling point of the liquid, to become larger container 320. An example of a suitable liquid is methanol which boils at about 65°C and water which boils at about 100°C at standard pressure. Other examples of suitable temperature expandable including wax are fully disclosed in US published patent application US 2006/0071088.

    [0052] While it is apparent that the illustrative embodiments of the invention disclosed herein fulfill the objectives stated above, it is appreciated that numerous modifications and other embodiments may be devised by those skilled in the art that fall within the scope of the appended claims.


    Claims

    1. A pressure regulator (164, 200) comprising:

    a movable shuttle (172) disposed between a high pressure diaphragm (174) and a low pressure diaphragm (176);

    a shuttle housing (170) to house the shuttle (172); and a conduit (190); wherein the conduit connects an inlet (178) to an outlet (180), the high pressure diaphragm (174) is located proximate to the inlet (178), and the low pressure diaphragm (176) is located proximate to the outlet (180);

    the pressure regulator further comprising a movable member (216) connected to the shuttle housing (170), characterized in that:

    said movable member (216) is movable to contact the low pressure diaphragm (176) to determine an area of said contacted diaphragm (176) that can flex; or,

    said movable member (216) is movable to contact the high pressure diaphragm (174), to determine an area of said contacted diaphragm (174) that can flex; and

    the movable member (216) has a shape of a circular ring and is adjustable to change an outlet pressure of the pressure regulator (164, 200).


     
    2. The pressure regulator of claim 1, wherein the shuttle (172) comprises a stem (220) and a low pressure base (222) and the stem (220) is movable relative to the low pressure base (222) to change a length of the shuttle (172).
     
    3. The pressure regulator of claim 1 further comprising a flow restrictor (224) connected to the conduit (190) connecting the inlet (178) to the outlet (180).
     
    4. The pressure regulator of claim 1 further comprising a flow restrictor (224) positioned between the outlet (180) of the pressure regulator and a fluid port (181) of a receiver of a fluid transporting through the pressure regulator.
     
    5. The pressure regulator of claim 1, wherein the shuttle housing (170) comprises a first and second half (166, 168) movable relative to each other to change a length of the shuttle housing (170).
     
    6. The pressure regulator (238) of claim 1, further comprising an inlet (178) and an outlet (180) and a flow restrictor (246) fluidly connected to the pressure regulator;
    wherein a fluid enters the inlet (178) at an inlet pressure and exits the outlet (180) at an outlet pressure;
    wherein the inlet pressure is higher than the outlet pressure; wherein the flow restrictor (246) allows said fluid or a second fluid to pass through when the fluid's pressure is higher than the flow restrictor's threshold pressure.
     
    7. The pressure regulator of claim 6, wherein the flow restrictor (246) comprises a relief valve fluidly connecting the outlet (180) of the pressure regulator to atmosphere and wherein the second fluid comprises air to allow air to pass through the flow restrictor (246) to the pressure regulator (238) to prevent a partial vacuum within the pressure regulator.
     
    8. The pressure regulator of claim 7, wherein the flow restrictor (246) is fluidly connected to the inlet (178) of the pressure regulator (238) to allow said fluid to enter the pressure regulator when said fluid's pressure exceeds the flow restrictor's threshold pressure.
     
    9. The pressure regulator (238) of claim 6, wherein the flow restrictor (246) comprises a bypass valve (290).
     
    10. The pressure regulator of claim 9, wherein the by-pass valve (290) is fluidly connected to the inlet (178) of the pressure regulator to allow said fluid to enter the pressure regulator (238) when said fluid's pressure exceeds the by-pass valve's threshold pressure and to allow said fluid to enter the by-pass valve (290) when said fluid's pressure is less than the by-pass valve's threshold pressure.
     
    11. The pressure regulator of claim 10, wherein the by-pass valve (290) comprises a diaphragm (298) connected to a valve seat (302) wherein the said fluid's pressure exceeds the by-pass valve's threshold pressure, the diaphragm (298) moves the valve seat (302) to a sealing position.
     
    12. The pressure regulator of claim 1 further comprising:
    a temperature sensitive component (312, 314, 316, 318, 320) disposed within the pressure regulator, so that when the temperature of the pressure regulator reaches a predetermined level, the temperature sensitive component (312, 314, 316, 318, 320) changes its shape to render the pressure regulator inoperative.
     


    Ansprüche

    1. Druckregler (164, 200), umfassend:

    ein bewegliches Schiffchen (172), das zwischen einer Hochdruckmembran (174) und einer Niederdruckmembran (176) angeordnet ist;

    ein Schiffchengehäuse (170), das das Schiffchen (172) beherbergt; und eine Leitung (190); wobei die Leitung einen Einlass (178) mit einem Auslass (180) verbindet, die Hochdruckmembran (174) nahe dem Einlass (178) liegt und die Niederdruckmembran (176) nahe dem Auslass (180) liegt;

    der Druckregler weiter ein bewegliches Element (216) umfasst, das mit dem Schiffchengehäuse (170) verbunden ist, dadurch gekennzeichnet, dass:

    das bewegliche Element (216) beweglich ist, um die Niederdruckmembran (176) zu berühren, um einen Bereich der berührten Membran (176) zu ermitteln, der sich biegen kann; oder

    das bewegliche Element (216) beweglich ist, um die Hochdruckmembran (174) zu berühren, um einen Bereich der berührten Membran (174) zu ermitteln, der sich biegen kann; und

    das bewegliche Element (216) eine Form eines kreisförmigen Rings aufweist und anpassbar ist, um einen Auslassdruck des Druckreglers (164, 200) zu ändern.


     
    2. Druckregler nach Anspruch 1, wobei das Schiffchen (172) einen Schaft (220) und eine Niederdruckbasis (222) umfasst und der Schaft (220) relativ zu der Niederdruckbasis (222) beweglich ist, um eine Länge des Schiffchens (172) zu ändern.
     
    3. Druckregler nach Anspruch 1, weiter umfassend einen Flussbegrenzer (224), der mit der Leitung (190) verbunden ist, die den Einlass (178) mit dem Auslass (180) verbindet.
     
    4. Druckregler nach Anspruch 1, weiter umfassend einen Flussbegrenzer (224), der zwischen dem Auslass (180) des Druckreglers und einem Fluidanschluss (181) eines Empfängers eines Fluids, das durch den Druckregler durchfließt, positioniert ist.
     
    5. Druckregler nach Anspruch 1, wobei das Schiffchengehäuse (170) eine erste und zweite Hälfte (166, 168) umfasst, die relativ zueinander beweglich sind, um eine Länge des Schiffchengehäuses (170) zu ändern.
     
    6. Druckregler (238) nach Anspruch 1, weiter umfassend einen Einlass (178) und einen Auslass (180) und einen Flussbegrenzer (246), der strömungstechnisch mit dem Druckregler verbunden ist;
    wobei ein Fluid in den Einlass (178) bei einem Einlassdruck eintritt und den Auslass (180) bei einem Auslassdruck verlässt;
    wobei der Einlassdruck höher als der Auslassdruck ist; wobei der Flussbegrenzer (246) dem Fluid oder einem zweiten Fluid erlaubt durchzugehen, wenn der Fluiddruck höher als der Schwellendruck des Flussbegrenzers ist.
     
    7. Druckregler nach Anspruch 6, wobei der Flussbegrenzer (246) ein Überdruckventil umfasst, das strömungstechnisch den Auslass (180) des Druckreglers mit Atmosphäre verbindet, und wobei das zweite Fluid Luft umfasst, um Luft zu erlauben, durch den Flussbegrenzer (246) zu dem Druckregler (238) zu gehen, um ein teilweises Vakuum innerhalb des Druckreglers zu verhindern.
     
    8. Druckregler nach Anspruch 7, wobei der Flussbegrenzer (246) strömungstechnisch mit dem Einlass (178) des Druckreglers (238) verbunden ist, um dem Fluid zu erlauben, in den Druckregler einzutreten, wenn der Fluiddruck den Schwellendruck des Flussbegrenzers übersteigt.
     
    9. Druckregler (238) nach Anspruch 6, wobei der Flussbegrenzer (246) ein Umgehungsventil (290) umfasst.
     
    10. Druckregler nach Anspruch 9, wobei das Umgehungsventil (290) strömungstechnisch mit dem Einlass (178) des Druckreglers verbunden ist, um dem Fluid zu erlauben, in den Druckregler (238) einzutreten, wenn der Fluiddruck den Schwellendruck des Umgebungsventils übersteigt, und dem Fluid zu erlauben, in das Umgehungsventil (290) einzutreten, wenn der Fluiddruck weniger als der Schwellendruck des Umgehungsventils ist.
     
    11. Druckregler nach Anspruch 10, wobei das Umgehungsventil (290) eine Membran (298) umfasst, die mit einem Ventilsitz (302) verbunden ist, wobei der Fluiddruck den Schwellendruck des Umgehungsventils übersteigt, die Membran (298) den Ventilsitz (302) zu einer Dichtungsposition bewegt.
     
    12. Druckregler nach Anspruch 1, weiter umfassend:
    eine temperaturempfindliche Komponente (312, 314, 316, 318, 320), die innerhalb des Druckreglers angeordnet ist, sodass, wenn die Temperatur des Druckreglers ein vorgegebenes Niveau erreicht, die temperaturempfindliche Komponente (312, 314, 316, 318, 320) ihre Form ändert, um den Druckregler stillzulegen.
     


    Revendications

    1. Régulateur de pression (164, 200) comprenant :

    une navette mobile (172) disposée entre une membrane à haute pression (174) et une membrane à basse pression (176) ;

    un logement de navette (170) pour loger la navette (172) ; et un conduit (190) ; dans lequel le conduit raccorde une entrée (178) à une sortie (180), la membrane à haute pression (174) est située à proximité de l'entrée (178), et la membrane à basse pression (176) est située à proximité de la sortie (180) ;

    le régulateur de pression comprenant en outre un élément mobile (216) raccordé au logement de navette (170), caractérisé en ce que :

    ledit élément mobile (216) est mobile pour entrer en contact avec la membrane à basse pression (176) pour déterminer une région de ladite membrane en contact (176) qui peut se plier ; ou,

    ledit élément mobile (216) est mobile pour entrer en contact avec la membrane à haute pression (174) pour déterminer une région de ladite membrane en contact (174) qui peut se plier ; et

    l'élément mobile (216) présente une forme d'un anneau circulaire et peut être ajusté pour modifier une pression de sortie du régulateur de pression (164, 200).


     
    2. Régulateur de pression selon la revendication 1, dans lequel la navette (172) comprend une tige (220) et une base à basse pression (222) et la tige (220) est mobile par rapport à la base à basse pression (222) pour modifier une longueur de la navette (172).
     
    3. Régulateur de pression selon la revendication 1, comprenant en outre un limiteur de débit (224) raccordé au conduit (190) raccordant l'entrée (178) à la sortie (180).
     
    4. Régulateur de pression selon la revendication 1, comprenant en outre un limiteur de débit (224) positionné entre la sortie (180) du régulateur de pression et un orifice de fluide (181) d'un récepteur d'un fluide transportant à travers le régulateur de pression.
     
    5. Régulateur de pression selon la revendication 1, dans lequel le logement de navette (170) comprend des première et seconde moitiés (166, 168) mobiles l'une par rapport à l'autre pour modifier une longueur du logement de navette (170).
     
    6. Régulateur de pression (238) selon la revendication 1, comprenant en outre une entrée (178) et une sortie (180) et un limiteur de débit (246) raccordé fluidiquement au régulateur de pression ;
    dans lequel un fluide entre dans l'entrée (178) à une pression d'entrée et sort de la sortie (180) à une pression de sortie ;
    dans lequel la pression d'entrée est supérieure à la pression de sortie ; dans lequel le limiteur de débit (246) permet audit fluide ou à un second fluide de traverser lorsque la pression du fluide est supérieure à la pression seuil du limiteur de débit.
     
    7. Régulateur de pression selon la revendication 6, dans lequel le limiteur de débit (246) comprend une soupape de surpression raccordant fluidiquement la sortie (180) du régulateur de pression à l'atmosphère et dans lequel le second fluide comprend de l'air pour permettre à l'air de traverser le limiteur de débit (246) vers le régulateur de pression (238) pour empêcher un vide partiel dans le régulateur de pression.
     
    8. Régulateur de pression selon la revendication 7, dans lequel le limiteur de débit (246) est raccordé fluidiquement à l'entrée (178) du régulateur de pression (238) pour permettre audit fluide d'entrer dans le régulateur de pression lorsque la pression dudit fluide dépasse la pression seuil du limiteur de débit.
     
    9. Régulateur de pression (238) selon la revendication 6, dans lequel le limiteur de débit (246) comprend une soupape de dérivation (290).
     
    10. Régulateur de pression selon la revendication 9, dans lequel la soupape de dérivation (290) est raccordée fluidiquement à l'entrée (178) du régulateur de pression pour permettre audit fluide d'entrer dans le régulateur de pression (238) lorsque la pression dudit fluide dépasse la pression seuil de la soupape de dérivation et pour permettre audit fluide d'entrer dans la soupape de dérivation (290) lorsque la pression dudit fluide est inférieure à la pression seuil de la soupape de dérivation.
     
    11. Régulateur de pression selon la revendication 10, dans lequel la soupape de dérivation (290) comprend une membrane (298) raccordée à un siège de soupape (302) dans lequel la pression dudit fluide dépasse la pression seuil de la soupape de dérivation, la membrane (298) déplace le siège de soupape (302) vers une position d'étanchéité.
     
    12. Régulateur de pression selon la revendication 1, comprenant en outre :

    un composant sensible à la température (312, 314, 316, 318, 320) disposé dans le régulateur de pression, de sorte que, lorsque la température du régulateur de pression atteint un niveau prédéterminé, le composant sensible à la température (312, 314, 316, 318, 320) modifie sa forme pour rendre le régulateur de pression inopérant.


     




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    REFERENCES CITED IN THE DESCRIPTION



    This list of references cited by the applicant is for the reader's convenience only. It does not form part of the European patent document. Even though great care has been taken in compiling the references, errors or omissions cannot be excluded and the EPO disclaims all liability in this regard.

    Patent documents cited in the description