Abstract:
Disclosed herein are connecting valves with an interchangeability feature ( 18, 20 ) to ensure that the fuel cell fuel matches the fuel cell. Also disclosed are retainer mechanisms ( 28, 30, 32, 36 ) capable of releasably connecting the fuel supply to the fuel cell or to the electronic device equipped with a fuel cell. An improvement to the connecting valves to decrease the amount of residual fuel left in the fuel supply is also provided.

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
       [0001]    The present application is a continuation-in-part of commonly-owned, co-pending PCT international application serial number PCT/US05/04826, filed on Feb. 16, 2005, the disclosure of which is incorporated herein by reference in its entirety. This international application designates the United States of America among other member states. 
     
    
     FIELD OF THE INVENTION 
       [0002]    This invention relates to a valve for connecting a fuel supply to a fuel cell or to an electronic device equipped with a fuel cell. 
       BACKGROUND OF THE INVENTION 
       [0003]    Valves that connect a fuel supply or fuel cartridge to a fuel cell or an electronic device equipped with a fuel cell have been disclosed. Suitable connecting valves are disclosed in commonly-owned and/or co-pending U.S. Pat. Appl. Pub. No. US 2005/0022883 A1, entitled “Fuel Cartridge with Connecting Valve”; U.S. Pat. Appl. Pub. No. US 2005/0074643 A1, entitled “Fuel Cartridges for Fuel Cells and Methods for Making Same”; U.S. Pat. Appl. Pub. No. US 2005/0116190 A1, entitled “Fuel Cell Supply Having Fuel Compatible Materials”; and U.S. Pat. Appl. Pub. No. US 2005/0118468 A1, entitled “Fuel Cell Supply Including Information Storage Device And Control System.” Other suitable connecting valves include commonly owned and/or co-pending PCT Pub. No. 2006/050261 A1, entitled “Valves for Fuel Cartridges,” and U.S. Patent Appl. Pub. No. 2006/0071088 A1, entitled “Fuel Cartridge with an Environmentally Sensitive Valve.” 
         [0004]    These pending applications and publications are specifically incorporated by reference herein in their entireties. 
         [0005]    The present invention is directed to an improved connecting valve. 
       SUMMARY OF THE INVENTION 
       [0006]    The present invention is directed to connecting valves with an interchangeability feature to ensure that the fuel cell fuel matches the fuel cell. 
         [0007]    The present invention is also directed to a retainer mechanism capable of releasably connecting the fuel supply to the fuel cell or the electronic device equipped with a fuel cell. 
         [0008]    The present invention is also directed to an improvement to the connecting valve to decrease the amount of residual fuel left in the fuel supply. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS  
         [0009]    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: 
           [0010]      FIG. 1  is an exploded view of the two valve components of a connecting valve of the present invention showing an interchangeability feature; 
           [0011]      FIG. 2  is a sectional view of the valve components of  FIG. 1  with details omitted for clarity; 
           [0012]      FIGS. 3A-C  are top views of various embodiments of the interchangeability feature of  FIG. 1 ; 
           [0013]      FIG. 4  is a top view of another embodiment of the interchangeability feature of  FIG. 1 ; 
           [0014]      FIG. 5  is an exploded view of the two valve components of  FIG. 1  with a retaining mechanism; 
           [0015]      FIG. 6  is a sectional view of the valve components of  FIG. 5  in the connected position with details omitted for clarity; 
           [0016]      FIGS. 7 and 8  show another embodiment of the retaining mechanism of  FIG. 5 ; 
           [0017]      FIGS. 9A-C  are cross-sectional views showing other inventive combinations of the retaining mechanism and interchangeability feature; and 
           [0018]      FIG. 10  is a sectional, exploded view of the valve components showing a mechanism to maximize the amount of fuel extractable from the fuel supply and a cover for the valve component. 
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION  
       [0019]    As illustrated in the accompanying drawings and discussed in detail below, the present invention is directed to valves for fuel supplies, which store fuel cell fuels, such as methanol and water, methanol/water mixture, methanol/water mixtures of varying concentrations, pure methanol, and/or methyl clathrates described in U.S. Pat. Nos. 5,364,977 and 6,512,005 B2, which are incorporated by reference herein in their entirety. Methanol and other alcohols are usable in many types of fuel cells, e.g., DMFC, enzyme fuel cells and reformat fuel cells, among others. The fuel supply may contain other types of fuel cell fuels, such as ethanol or alcohols, metal hydrides, such as sodium borohydrides, other chemicals that can be reformatted into hydrogen, or other chemicals that may improve the performance or efficiency of fuel cells. Fuels also include potassium hydroxide (KOH) electrolyte, which is usable with metal fuel cells or alkali fuel cells, and can be stored in fuel supplies. For metal fuel cells, fuel is in the form of fluid-borne zinc particles immersed in a KOH electrolytic reaction solution, and the anodes within the cell cavities are particulate anodes formed of the zinc particles. KOH electrolytic solution is disclosed in U.S. Pat. Appl. Pub. No. US 2003/0077493 A1, entitled “Method of Using Fuel Cell System Configured to Provide Power to One or More Loads,” published on Apr. 24, 2003, which is incorporated by reference herein in its entirety. Fuels can also include a mixture of methanol, hydrogen peroxide and sulfuric acid, which flows past a catalyst formed on silicon chips to create a fuel cell reaction. Moreover, fuels include a blend or mixture of methanol, sodium borohydride, an electrolyte, and other compounds, such as those described in U.S. Pat. Nos. 6,554,877; 6,562,497; and 6,758,871, which are incorporated by reference herein in their entireties. Furthermore, fuels include those compositions that are partially dissolved in a solvent and partially suspended in a solvent, as described in U.S. Pat. No. 6,773,470 and those compositions that include both liquid fuel and solid fuels, described in U.S. Pat. Appl. Pub. No. US 2002/0076602 A1. Fuels also include formic acid. These references are also incorporated by reference in their entireties. 
         [0020]    Fuels can also include a metal hydride such as sodium borohydride (NaBH 4 ) and water, discussed above. 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 2003/0096150 A1, entitled “Liquid Hereto-Interface Fuel Cell Device,” published on May 22, 2003, which is incorporated by reference herein in its entirety. Fuels can also include liquid oxidants that react with fuels. Of course, fuels also include hydrogen, which can be compressed, stored in metal hydrides, or created from a reaction with a hydride, etc. 
         [0021]    The present invention is therefore not limited to any type of fuel, electrolytic solution, oxidant solution 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 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 and mixtures thereof. The fuel supply of the present invention can also be used to store fuels that are not used in fuel cells. These applications include, but are not limited to, storing hydrocarbons and hydrogen fuels for micro gas-turbine engines built on silicon chips, discussed in “Here Come the Microengines,” published in The Industrial Physicist (December 2001/January 2002), at pp. 20-25. For the purpose of the present application, “fuel cells” also include these micro-engines. Other applications include storing traditional fuels for internal combustion engines, hydrocarbons such as butane for pocket and utility lighters, and liquid propane. 
         [0022]    Due to the multiple types of fuel cell fuels, it is desirable that the fuel supplies can be distinguished from each other, so that a fuel supply containing one type of fuel would not be used with a fuel cell requiring a different type of fuel. Such mismatch can be minimized by incorporating interchangeability features to the fuel supplies, the valves and/or the electronic devices. Suitable interchangeability features for fuel supplies have been fully disclosed in commonly owned, co-pending U.S. patent application Ser. No. 10/773,481, entitled “Datum Based Interchangeable Fuel Cell Cartridges,” filed on Feb. 6, 2004, and published as U.S. Pat. Appl. Pub. No. 2005/0173022. This application is incorporated by reference herein in its entirety. 
         [0023]    In accordance with one aspect of the present invention, interchangeability for fuel supply valves is accomplished by keys or keying features, which allow a fuel supply to be connected to a fuel cell only when the keys on the valve of the fuel supply match with the keys on the valve connected to the fuel cell or to the device with a fuel cell. The keys can be protrusions on or recesses within the valve body or the keys can be located on an outer surface of the valve, be directly or indirectly connected to the valve, on the fuel supply, or on a movable sealing body within the valves. The keys can also be visual keys. Suitable keys have been disclosed in commonly owned parent International Patent Application No. PCT/US05/04826, entitled “Fuel Supply Systems Having Operational Resistance,” filed on Feb. 16, 2005. This parent international application is incorporated herein by reference in its entirety. 
         [0024]    Referring to  FIG. 1 , a connecting valve  10  is a two-component valve that includes valve components  12  and  14  with an interchangeability feature. Preferably, each valve component comprises an internal seal (such as a check valve, a duckbill valve or a solenoid valve), although internal seals are not always necessary. Two-component valves are fully disclosed in the patent references listed above, and particularly in US 2005/0022883 and WO 2006/050261. Valve component  12  or  14  can be attached to either the fuel supply or the device/fuel cell. As shown, valve component  12  has a rim  16 , which has at least one key  18  disposed thereon or dependent therefrom. Preferably, rim  16  has more than one key  18 . In this embodiment, key  18  is a rectangular protrusion or tooth, but in other embodiments key  18  can have any shape or size. Valve component  14  has a corresponding key  20 , which is a recess, sized and dimensioned to receive key  18 . Key  20  can be formed within a body of valve component  14  or within a rim  22 , as shown. Protruding key  18  can be located on the other valve component  14 , and corresponding recessed key  20  can be located on valve component  12 . Rim  16  and rim  22  are shown as circular; however, these rims can have any shape including oval, regular polygons, or irregular polygons. 
         [0025]    The distance or angle  24 ,  24 ′,  24 ″ between the corresponding reference points on adjacent keys  18  can vary, as shown in  FIGS. 3A-3C , to indicate the type of fuel contained in the fuel supply and unless corresponding keys  20  match keys  18 , the fuel supply will not be allowed to connect to the fuel cell. In other words, angles  24 ,  24 ′, and  24 ″ are different from each other and each angle represents a different type of fuel or different grade of fuel. Alternatively, angle  24  can be replaced by the complementary obtuse angle  26 , as shown in  FIG. 4 . Keys  18 ,  20  can have the same or different width, as long as one is receivable by the other one. Angles  24 ,  26  can be selected to be divisible by a common angle, such as 30° or 45°, or may be divisible by an uncommon angle, e.g., 13° or 27°, to produce unique keys. A distance  4  from a tip of key  18  to an end  19  of valve component  12  should be standardized to match a distance  5  between a bottom of corresponding key  20  and a mating surface  23  of valve component  14  to ensure proper engagement between the two valve components. Proper engagement of fuel supply to fuel cell (or devices equipped with fuel cell) can be accomplished by relation to an arbitrary datum, which is fully disclosed in the &#39;481 application, discussed above. 
         [0026]    Interchangeability of the valve components in accordance with the present invention also includes matching multiple types of fuel supplies to a single type of fuel cell. For example, a single direct methanol fuel cell may accept several different types of methanol fuels, such as methanol with or without additives, methanol with varying percentages of concentrations, or methanol with other alcohols added therein. Hence, so long as the valve components are interchangeable, the different types of fuel supplies can be used with a particular fuel cell. 
         [0027]    In accordance with another aspect of the present invention, a retaining device is added to valve  10 . As illustrated in  FIGS. 5 and 6 , an internally threaded sleeve  28  is attached to valve component  12  (or to valve component  14 ), such that sleeve  28  is rotatable relative to the valve component. A portion of the outer surface of corresponding valve component  14 , preferably rim  22 , is also threaded to engage threaded sleeve  28 . The engagement of valve component  12  to valve component  14  can be accomplished by the rotation of sleeve  28  to engage the threads  30 . Valve components  12  and  14  can be disengaged by counter-rotation of sleeve  28 . 
         [0028]    Another embodiment of the retention device is shown in  FIGS. 7 and 8 . Here, valve component  14  has at least one hook  32  disposed thereon. Preferably, hook  32  is located on rim  22 , but can be located elsewhere. Valve component  12  is equipped with a plate  34  having at least one catch, e.g., hole  36 , which is sized and dimensioned to receive hook  32 . As shown in  FIG. 8 , after hook  32  passes through catch or hole  36 , the enlarged head of hook  32  snaps over the top of plate  34  to secure valve components  12  and  14  to each other. Plate  34  also has release arm(s)  38  disposed thereon. Arms  38  are movable relative to plate  34  and can be pressed against the enlarged head of hook  32 , as shown by arrows  40 , to release hook  32 . After hook  32  is pressed in the direction of arrows  40 , valve components  12  and  14  can be disengaged from each other. Hook  32  can be located on either valve component. Additionally, hook(s)  32  and catch(es)  36  can also provide an interchangeability feature similar to keys  18  and  20  since hook(s)  32  have to be aligned with catch(es)  36  before valve components  12  and  14  can engage one another. Hence, unique locations of hook(s)  32  and catch(es)  36  can be dedicated to correspond to unique fuel. 
         [0029]    Release arms  38  can be omitted, if this retention feature is a snap fit that is separable by force or requires relative rotational movements between the two valve components to disengage the valve components from each other. Other suitable retention devices are disclosed in commonly owned U.S. provisional patent application Ser. No. 60/699,854, entitled “Separable Fuel Cartridge,” filed on Jul. 18, 2005, and is incorporated by reference herein in its entirety. 
         [0030]    As discussed above, the retaining device(s) can be used alone or with the interchangeability feature. The combination of interchangeability feature and retaining device may have other configurations, such as those shown in  FIGS. 9A-C . Here, key  18  can be positioned on the same valve component as hook  32 . Key  18  can have any height (a) or (a′) and width (b) or (b′), and can be located adjacent to a body portion of valve component  12 ,  14 . Keys  18  can also be located adjacent to hook  32 , or located spaced from the valve body portion and the hooks. Keys  18  can also have any profile, such as quadrilateral, triangular, circular (including half-circle shapes) or any arbitrary shape. Additionally, the enlarged head of hook  32  can be facing outward, as shown, or inward. Hook  32  can also be oriented sideway if the hook can flex to allow straight insertion, or the valve components can be rotated relative to each other to engage each other. Keys  18  can also be positioned angularly around rim  16  at different angles. 
         [0031]    Another improvement to valve  10  of the present invention is shown in  FIG. 10 . As shown, one of valve components ( 12 ,  14 ) is attached to a fuel supply  42 , which contains a fuel  44 , and the other valve component is connected to a fuel cell or a device equipped with a fuel cell. When the length of a valve component penetrates relatively deep into the fuel supply, more residual fuel can be trapped in the fuel supply not being used. More specifically, in conventional fuel supplies the residual fuel located between a top wall  46  of fuel supply  42  and a distal end  48  of valve component  12 ,  14  may become trapped. However, to maximize the amount of fuel retrievable from fuel supply  42 , aperture(s)  50  is cut out from a body of the valve component, and preferably aperture  50  is in fluid communication with residual fuel  44  and is positioned as flush with top wall  46  as possible. In another embodiment, aperture  50  can also be a U-shaped cut-out running toward distal end  48 . 
         [0032]    Another improvement of the present invention is an optional cover  52  that can be placed on one or both valve components  12  and  14 , as shown in  FIG. 10 , to provide support for the valve component. Cover  52  preferably includes an aperture and an absorbent material  54  disposed at an outer tip of valve component  12 ,  14  as shown. When valve components  12  and  14  are engaging each other or are being disengaged from each other, residual fuel within or between the valve components may be absorbed by absorbent material  54 . Absorbent material  54  can be any material that can absorb fuel, including sponges, foams or fillers. Suitable fillers include polymeric fibers, such as polyester, polyethylene, polyolefin, polyacetal, or polypropylene fibers, or plant-based fibers, such as hemp, cotton, or cellulose acetate. 
         [0033]    Additionally, an optional elastomeric disk  56  can be placed above absorbent material  54 . Disk  56  can be placed outside cover  52 , as shown, or inside cover  52 . Preferably, elastomeric disk  56  has an aperture or slit  58 , which is adapted to allow the other valve component, e.g., the top valve component in  FIG. 10 , to pass through. Aperture  58  acts as a wiper to keep residual fuel within cover  52  as the top valve component is being withdrawn. Preferably, aperture  58  forms a seal with the inserting or withdrawing valve component. Optionally, aperture  58  is a closed slit to form another seal outside of cover  52 . 
         [0034]    Additionally, a cap  60  can be placed on top of one or both valve components  12  and  14 . Cap  60  can protect the valve component or fuel supply if the cap is used with the fuel supply during shipping and handling. Cap  60  can be removed prior to use and can be replaced to protect the valve component when no longer in use. Cap  60  can be made from an elastomeric material, a plastic, etc., and can be placed or stretched over the cover  52 . If cap  60  is made of an elastomeric material, then it may have an aperture similar to aperture  58  described above and functions similar to aperture  58  and does not need to be removed. Cap  60  can also be made of a rigid material, such as plastic or metal. Additionally, multiple motions may be required to remove cap  60  from the valve component, e.g., cap  60  may be attached to the valve component via a bayonet mount or through an L-shaped channel and corresponding protrusion sliding in the channel. Such caps, including multiple-motion caps, are disclosed in International Patent Application No. PCT/US 05/04826, discussed above. 
         [0035]    Valve components  12  and  14  are illustrated in  FIG. 10  with relevant internal mechanism, and as shown each comprises a check valve. For clarity these internal mechanism are omitted from the valve components in the other Figures. However, it is understood that valve components  12  and  14  may include a check valve therein. Additionally, the interchangeability device and the retaining mechanism shown in  FIGS. 1-9  can be used with the valve components of  FIG. 10 . 
         [0036]    As used herein, the term “fuel supply” includes, but is not limited to, disposable cartridges, refillable/reusable cartridges, containers, cartridges that reside inside the electronic device, removable cartridges, cartridges that are outside of the electronic device, fuel tanks, fuel refilling tanks, other containers that store fuel and the tubes connected to the fuel tanks and containers. While a cartridge is described below in conjunction with the exemplary embodiments of the present invention, it is noted that these embodiments are also applicable to other fuel supplies and the present invention is not limited to any particular type of fuel supply. 
         [0037]    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. Therefore, it will be understood that the appended claims are intended to cover all such modifications and embodiments, which would come within the spirit and scope of the present invention.