Abstract:
There is provided a beverage maker having a device that removes contaminants from a liquid, which is removably supported within a compartment for ingredients. The device is preferably a filter that is surrounded by a supporting member, which supports the device within the compartment. The supporting member around the device may have a plurality of outwardly-protruding extensions that support the device by fitting against the sidewall of the compartment. A method and a system for such a device are also provided.

Description:
[0001]    This application claims priority from U.S. Provisional Patent Application Ser. No. 60/177,188, filed on Jan. 15, 2000. 
     
    
     
       FIELD OF THE INVENTION  
         [0002]    The present invention relates to a device capable of removing contaminants in a liquid and a method and system for such a device. More particularly, this invention relates to a device used in a brewed beverage maker for removing contaminants in a liquid and a method and system such a device.  
         BACKGROUND OF THE INVENTION  
         [0003]    Devices of various configurations for removing contaminants from liquids are employed daily in households. The term removing as used herein encompasses actions against a contaminant, such as separating, absorbing, adsorbing, capturing, binding, altering, transforming, rendering inert, and destroying.  
           [0004]    In most households, coffee, tea, and other brewed beverages are typically made in automatic drip-type beverage makers. Such beverage makers typically have a reservoir of liquid, such as water, and heat the liquid with a thermo-siphon heater. The heated liquid is delivered to a brewing basket that contains the brewing ingredients, wherein the heated liquid steeps in the brewing ingredients. The resulting brewed beverage passes through the brewing basket into a beverage collector, or carafe, positioned below. The beverage collector is typically kept warm by a heating element.  
           [0005]    Water and other liquids used in these drip-type beverage makers can contain contaminants. These contaminants include particulates, chemicals, and germs (i.e., viruses, bacteria, mold, pollen, oocysts, and protozoa). Common liquid-borne particulate contaminants are dirt, rust, silt, and heavy metals. Lead, a heavy metal, is particularly common because it is found in water fixtures, pipes, and pipe solder. Chemical contaminants may consist of chlorinated hydrocarbons, free chlorine, pesticides, petroleum-based chemicals, and synthetic organic chemicals. Germs that commonly contaminate water include protozoan cysts, such as Cryptosporidium Parvum and Giardia, and bacteria, such as  E. coli  and Cholera. Thus, not only will contaminants noticeably and adversely affect the aroma, taste, and other qualities of the brewed beverage, contaminants are also potentially dangerous to the brewed beverage drinker.  
           [0006]    The typical brewing basket found in most beverage makers is roughly shaped as an inverted cone, conoid, or pyramid. The brewing basket supports a fluted or pleated bowl-shaped paper filter that generally conforms to the shape of the brewing basket. The principal function of the paper filter is to support the brewing ingredients and prevent them from passing into the underlying beverage collector. Thus, the paper filter that is held in the brewing basket generally does not remove liquid-borne contaminants.  
           [0007]    A contaminant remover must be employed to remove or otherwise render inert contaminants in the liquid, ideally, before the liquid contacts the brewing ingredients. Yet, typical beverage makers cannot fit a contaminant remover between the liquid reservoir and the brewing ingredients. Reasons for this include the fact that beverage makers for home use must be compact. Also, retrofitting a contaminant remover is often not possible.  
           [0008]    U.S. Pat. Nos. 5,318,703, 5,393,548, and 5,505,120 provide similar methods and devices for retrofitting a contaminant remover into a coffee maker. First, U.S. Pat. No. 5,318,703 provides a water filter module that includes a plurality of support feet. In operation, the water filter module is placed with its support feet on top of a mound of ground coffee. Second, U.S. Pat. No. 5,393,548 provides a method wherein a water filtration device is positioned between the hot water drip outlet and the ground coffee beans. In use, the water filtration device is inserted into the brewing basket such that the device rests on the ground coffee beans. Third, U.S. Pat. No. 5,505,120 provides an apparatus for brewing coffee having a basket for accommodating coffee grounds and a filter means located in the basket. The filter means is placed on top of the coffee grounds.  
           [0009]    These designs suffer from several drawbacks. First, the filter device, or contaminant remover is positioned in very close proximity to the coffee grounds. Accordingly, the contaminant remover can become tainted with wet coffee grounds, thus, requiring that the contaminant remover be cleaned after each use, which is clearly inconvenient. Furthermore, the filter device is not in contact with the sidewalls of the brew basket, which results in the filter device being stabilized only by the loose brewing ingredients upon which it is placed.  
           [0010]    The prior art illustrates that, although many different devices presently exist that remove contaminants in liquid used to brew beverages, there is still a need for a device that can be used in existing beverage makers to remove liquid-borne contaminants, is convenient to use, clean, and replace, and has a low resistance to flow. Ideally, such a contaminant remover will not come in contact with the brewing ingredients.  
         SUMMARY OF THE INVENTION  
         [0011]    There is provided a beverage maker having a device that removes contaminants from a liquid, which is removably supported within a compartment for ingredients. The device is preferably a filter that is surrounded by a supporting member, which supports the device within the compartment. The supporting member around the device may have a plurality of outwardly-protruding extensions that support the device by fitting against the sidewall of the compartment. A method and a system for such a device are also provided. 
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0012]    [0012]FIG. 1 is a perspective view of a device according to the present invention;  
         [0013]    [0013]FIG. 2 a top view of the device of FIG. 1;  
         [0014]    [0014]FIG. 3 is a cross-sectional view of the device of FIG. 1 along line a-a;  
         [0015]    [0015]FIG. 4 is a cross-sectional view of a brewing basket having the filter of FIG. 1 positioned therein;  
         [0016]    [0016]FIG. 5 is a cross-sectional view of a preferred embodiment of the filter media for the filter of FIG. 1; and  
         [0017]    [0017]FIG. 6 is a cross-sectional view of an alternate preferred embodiment of the filter media for the filter of FIG. 1.  
         [0018]    [0018]FIGS. 7 through 11 is a device according to the present invention having filter medium supports adapted for use as an integrated handle.  
     
    
     DETAILED DESCRIPTION OF THE INVENTION  
       [0019]    [0019]FIG. 1 illustrates a contaminant removing device embodying the present invention, referred to generally as  10 , which is adapted to remove contaminants from a liquid used to brew beverages. Device  10  preferably has a filter medium  20  and a surrounding wall or frame  12 . Device  10  is ideally intended for use in brew basket  50  (see FIG. 4) of a typical brewed beverage maker and the area and height of device  10  are preferably dimensioned so that device  10  will fit completely therein, yet remain separated from any brewing ingredients  55  contained in brew basket  50 .  
         [0020]    Wall or frame  12  surrounds filter medium  20  and is adapted to support filter medium  20  during the use of device  10 . Wall  12  may be formed of any suitable material and, preferably, is formed of a thermoplastic material, such as polyethylene.  
         [0021]    A reserve capacity is preferably created by extending wall  12  above filter medium  20  since liquid may enter device  10  more quickly than it can pass therethrough. The reserve capacity is defined by a distance d (see FIG. 3), which is between a top rim  14  of wall  12  and filter medium  20 , multiplied by the area of filter medium  20 . The area of filter medium  20  should be made as large as reasonably possible, while distance d should be configured to provide enough reserve capacity to prevent the overflow of liquid. The preferred distance d will depend on the flow rate of liquid through filter medium  20  and the size of brew basket  50 .  
         [0022]    Although wall  12  is preferably an annular sidewall surrounding a circular-shaped filter medium  20 , wall  12  may take any form dictated by the application environment. A circular shape is useful for a brew basket that is generally shaped as an inverted cone or conoid. Also, wall  12  may be provided with features that are appropriate for the application environment, such as an inwardly projecting semicircular indentation  15  or a tapered bottom rim  13  (not shown).  
         [0023]    Wall  12  may be releasably or permanently attached to filter medium  20  using any technique know to the art. For example, in a preferred embodiment of device  10 , filter medium  20  is heat sealed to wall  12 . Wall  12  may alternatively be insert molded around filter medium  20 . A further alternative would be adapting wall  12  to releasably receive filter medium  20  so that filter medium  20  could be replaced when necessary. If filter medium  20  was releasably attached to wall  12 , it would be preferable that filter medium  20  have a rigid or semi-rigid rim disposed thereabout, which is adapted to be snap-fit onto wall  12 .  
         [0024]    Wall  12  is preferably provided with a plurality of outwardly protruding extensions  18 . Although, extensions  18  may extend from top rim  14  of wall  12  or at substantially any position between top rim  14  and a bottom rim  13 , extensions  18  are preferably disposed in close proximity to bottom rim  13 . Extensions  18  protrude outwardly a sufficient length to enable contact with brew basket  50  (see FIG. 4). It is preferable that extensions  18  are flexibly attached to wall  12  so that extensions  18  may move relative to wall  12 . By flexibly connecting extensions  18  to wall  12 , exentions  18  may pivot relative to wall  12  until to top of device  10  sits below the top rim  61  of beverage brewing basket  50 , while remaining above the brewing ingredients. The flexing area of extensions  18  are preferably designed to allow for maximum flexing with minimum force, without fracturing. Extensions  18  may be initially set perpendicular or at an angle relative to wall  12 . Extensions  18  are preferably formed of the same or similar material as wall  12 . Furthermore, extensions  18  are preferably integrally formed with wall  12 .  
         [0025]    Supports  16  may be attached to wall  12  and project inwardly so as to reinforce filter medium  20 . A set of supports  16  may be positioned both on top and below filter medium  20 . Supports  16  may also be configured as inwardly projecting fins (see FIG. 3), which extend in parallel with wall  12 , as well as project inwardly therefrom. If supports  16  are configured as fins, supports  16  may be adapted for a user to grip device  10  therewith. Like extensions  18 , it is preferable that supports  16  be formed of the same or similar material as wall  12 . It is also preferable that supports  16  are integrally formed with wall  12 .  
         [0026]    Device  10  may include a pair of opposing inwardly projecting ridges  17   a  and  17   b  (see FIG. 3) disposed in close proximity to the top rim  14 . Ridges  17   a,    17   b  are intended to releasably engage a pair of grooves  72   a,    72   b  located at flared opposite ends of an elongated handle  70 . To facilitate the attachment of handle  70  to wall  12 , the opposing inwardly projecting ridges  17   a,    17   b  may be positioned at a remote end of a pair of opposing resilient cantilevered latching members  78   a,    78   b.  Cantilevered latching members  78   a,    78   b  may be made slightly shorter than top rim  14  so as to provide notched regions for receiving flared handle ends  74   a,    74   b  and for permitting handle  70  to sit substantially flush with top rim  14 , thusly providing a compact assembly. Alternatively, handle  70  may be integrally attached to wall  12 .  
         [0027]    Filter medium  20  may be of any type including separating mediums and adsorbing mediums. For example, metallic mesh screens, spun-bonded or melt-blown polymeric non-woven materials, glass fibers, porous membranes, and paper may be used as separating mediums. Adsorbing mediums include iodinated resin, activated carbon, activated alumina, alumina-silicates, ion-exchange resins, manganese or iron oxides, and other materials having well-defined pore structures due to a high degree of crystallinity, such as zeolites. Filter medium  20  should provide suitably high flow and minimal pressure drop because the reserve capacity may be limited due to practical height constraints placed on the brewed beverage maker, particularly if designed for domestic use.  
         [0028]    As shown is FIG. 5, filter medium  20  is most preferably a composite structure formed by an adsorbent supporting web substrate  70  having a surface  72  fused to a mixture of adsorbent particles  74  and binder particles  76 . Adsorbent particles  74  are coalesced or fused together by binder particles  76 , which are interposed therebetween. Also, some of the binder particles are fused to surface  72 . The composite structure is preferably obtained according to the method described in U.S. Pat. No. 5,792,513, issued on Aug. 11, 1998, which is incorporated in its entirety herein by reference. As described therein, a mixture of adsorbent particles  74  and binder particles  76  is applied to part or all of surface  72 , thereby producing a loose powder coating on surface  72 . The loose powder coating is heated to at least the Vicat softening temperature of binder particles  76 , but below the melting temperature of adsorbent supporting substrate  70  and adsorbent particles  74 . Pressure is applied to web substrate  70  to cause the softened binder particles to coalesce, or fuse together, adsorbent particles  74 , as well as adhere adsorbent particles  74  to adsorbent supporting web substrate  70 .  
         [0029]    Filtration medium  20  comprises an adsorbent supporting web substrate  70  that may be formed preferably using non-woven fibrous materials, such as the spun-bonded polyesters and polyolefins. Woven substrates may also be used. Furthermore, adsorbent supporting web substrate  70  may optionally be formed using cellulosic materials, such as paper, or a combination of cellulosic and thermoplastic fibers.  
         [0030]    Materials forming binder particles  76  typically include thermoplastics such polypropylene, linear low-density polyethylene, low density polyethylene and ethylene-vinyl acetate copolymer.  
         [0031]    Referring to FIG. 6, filter medium  20  can be modified to include an overlying web substrate  78 , which could be formed of materials similar to supporting web substrate  70 . Overlying web substrate  78  has a surface  80  facing coated surface  72  of adsorbent supporting web substrate  70 . Adsorbent particles  74  may also be adhered to surface  80  of overlying web substrate  78  by binder particles  76 . The fusing of adsorbent particles  74 , supporting substrate  70 , and overlying web substrate  78  can be accomplished according to the disclosure in U.S. Pat. No. 5,792,513. Essentially, after applying the mixture of adsorbent and binder particles to the surface of adsorbent supporting web substrate  70  to produce a powder coating covering at least a portion thereof, as described above, overlying web substrate  78  is applied over both adsorbent supporting web substrate  70  and the powder coating thereon. Heat and pressure is applied to adsorbent supporting web substrate  70  and overlying web substrate  78  to soften binder particles  76 . The softened binder particles coalesce, or fuse together, adsorbent particles  74 , as well as adhere adsorbent particles  74  to web substrates  70 ,  78 .  
         [0032]    Both the adsorbent supporting web substrate  70  and the overlying web substrate  78  may provide supplemental particulate filtration. For example, filter medium  52  can reduce certain waterborne oocysts when web substrate  70  and overlying web substrate  78  are composed of a fine hydrophilic particulate filter medium, potentially combined with adsorbents such as activated carbon and heavy metal adsorbing zeolites. Co-pending U.S. patent application Ser. No. 09/140,924, filed Aug. 27, 1998, and assigned to the assignee hereof describes a low flow resistance composite filter medium for capturing at least 99.95 percent of particulates of a size in the 3 to 4 micron range, such as oocysts, and dissolved chemical contaminants from a fluid that can be used as a high flow rate filter medium in the present invention. The subject matter of that application is incorporated herein by reference in its entirety.  
         [0033]    In use, as illustrated in FIG. 4, a liquid permeable holder for brewing ingredients, such as paper coffee grounds filter  53 , is placed within brew basket  50  and brewing ingredients are placed thereupon. Optionally, brewing ingredients can simply be placed within brew basket  50 . Device  10  is then fitted within brew basket  50 . Extensions  18  engage brew basket  50 . Thereby, brew basket  50  supports device  10  between top rim  51  and brewing ingredients  55 . In addition, brew basket  50  may be provided with indentations  57   a,    57   b  to better facilitate the fitting of device  10 . Liquid is then passed through device  10 . Contaminants in the liquid are removed, killed, or rendered inert by device  10  before the liquid mixes with brewing ingredients  55 .  
         [0034]    During use, device  10  is in direct contact with the liquid being passed therethrough. When hot liquid (about 185° F.) is used, the material forming device  10  is heated, which reduces the stresses incurred at the hinge areas of extensions  18 . Reducing the stress at the hinge areas results in extensions  18  taking on a permanent set for future use.  
         [0035]    There are two primary benefits of fitting device  10  distal to top rim  51  and separated from brewing ingredients  55 . First, device  10  may be retrofitted into virtually any beverage brewer. Second, device  10  will not become contaminated with wet brewing ingredients.  
         [0036]    The present invention having been thus described with particular reference to the preferred form thereof, it will be obvious that various changes and modifications may be made therein without departing from the spirit and scope of the invention as defined in the appended claims.