Abstract:
A system for brewing a beverage from a liquid. The system preferably has a device for steeping brewing ingredients in a liquid. The liquid is delivered to the steeping device through a contaminant removing device, such as a filter. The contaminant removing device is alternatively disposed, by way of a positioning device, either between the liquid supply and the steeping device or in a position wherein the contaminant removing device can be dried, cleaned, or replaced. A method of using such a system is also provided.

Description:
FIELD OF THE INVENTION 
     The present invention relates to a system capable of removing contaminants in a liquid and a method for using such a system. More particularly, this invention relates to a brewed beverage making system capable of removing contaminants from a liquid used to brew beverages. 
     BACKGROUND OF THE INVENTION 
     Devices of various configurations for removing contaminants from liquids are employed daily in households. The term removing as used herein encompasses separating, absorbing, adsorbing, capturing, binding, altering, transforming, rendering inert, and destroying. 
     In most households, coffee, tea, and other brewed beverages are typically made in an automatic drip-type beverage maker. 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. 
     Water and other liquids used in these drip-type beverage making systems 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. 
     The typical brewing basket found in most beverage makers has an inverted frustoconical shape and supports a fluted or pleated bowl-shaped paper filter or metal, open-mesh screen that generally conforms to the inverted frustoconical shape of the brewing basket. The principal function of the paper or open-mesh filter is to support the brewing ingredients and prevent them from passing into the underlying beverage collector. Thus, the paper or metal filter that is held in the brewing basket generally does not remove liquid-borne contaminants. 
     A contaminant remover must be employed to remove, or otherwise render inert, any contaminants in the liquid, ideally, before the liquid contacts the brewing ingredients. Yet, if a user finds the contaminant remover inconvenient to use, the user is likely to discontinue using, cleaning, or changing it. Moreover, if the contaminant remover is not integrated with the brewed beverage maker, the contaminant remover is likely to be lost or damaged. 
     U.S. Pat. No. 3,405,630 (R. L. Weber III) discloses a water filter disposed in the path of flow between an independently claimed water-heating vessel and a coffee infusion chamber. The specification of the Weber &#39;630 patent provides that the coffee maker is configured to receive the water filter by means of a threaded retaining ring. Since the water filter is threaded into the coffee maker, access thereto is not very convenient for the user. Also, after the water filter is installed, it is hidden within the coffee maker. Thus, there is a great likelihood that the filter will be either forgotten or not replaced regularly by the user. 
     U.S. Pat. No. 3,804,635 (Weber) provides a system having filtering material, such as activated carbon, located between the heating chamber and the coffee basket. However, the Weber &#39;635 patent does not provide that the filter material can be changed or cleaned by the user. More appropriately, this patent also discloses a coffee maker having a water filter at the inlet to the heating chamber. While only partially explained by the specification, changing the water filter element appears to require unscrewing a guide shaft, inserting the filter element, turning the element to securely lock it to the coffee maker, and then re-attaching the shaft. Clearly, this is not a convenient system and, moreover, the filter element is not integrated with the coffee maker. Thus, the user is likely not to install, clean, or change the filter element, and the filter element is likely to be lost or damaged. 
     U.S. Pat. Nos. 5,393,548 and 5,505,120 provide similar methods and devices for increasing the convenience of water filters for coffee makers. First, U.S. Pat. No. 5,393,548 (Heiligman) discloses a method wherein a water filtration device is positioned between the hot water drip outlet and the ground coffee beans. The specification provides a water filtration device having support feet. In use, the water filtration device is inserted into the brewing basket such that the support feet rest on the ground coffee beans. Second, U.S. Pat. No. 5,505,120 (Albertson) discloses a system for brewing coffee having a basket for accommodating coffee grounds and a filter means located in the basket. Like the Heiligman patent, the Albertson patent provides that the filter means is placed on top of the coffee grounds. 
     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. Moreover, because the prior art designs dispose the water filter between the water reservoir and the brewing basket, but not connected to either, each time coffee is made, the filter must be removed and repositioned. In some household or work environments, several batches of coffee are made each day and the removal, cleaning and repositioning of the filter can become a major inconvenience. 
     The prior art illustrates that, although many different beverage brewing systems presently exist, there is still a need for a beverage brewing system with a contaminant remover that is convenient to install, use, clean, and replace. In addition, a need exists for a beverage brewing system with a contaminant remover that will not be lost or damaged. 
     SUMMARY OF THE INVENTION 
     There is provided a system for removing contaminants from liquids. This system is preferably used for brewing beverages. The system employs a contaminant remover to remove impurities in a liquid prior to mixing the liquid with brewing ingredients contained in a brewing basket. The contaminant remover is convenient to install, use, clean, or replace because it is independently accessible relative to the brewing basket. A method for using the system is also provided. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a side projection view of a preferred embodiment of a beverage brewing system incorporating the unique contaminant remover of the present invention; 
     FIG. 2A is a top plan view of the beverage brewing system of FIG. 1 illustrating the operative position for a preferred embodiment of the supporting device for the contaminant remover; 
     FIG. 2B is a top plan view of the beverage brewing system of FIG. 1 illustrating the inoperative position of the supporting device of FIG. 2A; 
     FIG. 3A is a top plan view of the beverage brewing system of FIG. 1 illustrating the inoperative position for another preferred embodiment of the supporting device; 
     FIG. 3B is a top plan view of the beverage brewing system of FIG. 1 illustrating the operative position for the supporting device of FIG. 3A; 
     FIG. 3C is a front view of the supporting device of FIG. 3A; 
     FIG. 3D is a front, perspective, exploded view of the supporting device of FIG. 3A and a preferred embodiment of a contaminant remover for use therewith; 
     FIG. 3E is a front, perspective, view of the supporting device of FIG. 3A; 
     FIG. 4A is a partial cross-sectional view of a means for connecting the contaminant remover to the supporting device; 
     FIG. 4B is a partial cross-sectional view of another means for connecting the contaminant remover to the supporting device; 
     FIG. 5A is a top plan view of the beverage brewing system of FIG. 1 illustrating the inoperative position for a third embodiment of the supporting device; 
     FIG. 5B is a side plan view of the supporting device of FIG. 5A; 
     FIG. 5C is a top plan view of FIG. 1 illustrating the operative position for the supporting device of FIG. 5A; 
     FIG. 5D is a side plan view of FIG. 5C; 
     FIG. 6A is a perspective view of a preferred contaminant remover according to the present invention; 
     FIG. 6B is a cross-sectional view of the contaminant remover of FIG. 6A; 
     FIG. 7A is a magnified cross-sectional view of a preferred embodiment of the contaminant remover according to the present invention; and 
     FIG. 7B is a magnified cross-sectional view of another preferred embodiment of the contaminant remover according to the present invention. 
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     FIG. 1 illustrates an embodiment for a beverage brewing system  10  according to the present invention. Beverage brewing system  10  is generally formed by a housing  12 . Housing  12  has a reservoir  14  disposed therein for holding liquids, such as water. Reservoir  14  is connected to a heater  16  by a conduit  18 , while heater  16  is connected to an outlet  20  by a conduit  22 . However, other means for supplying hot water through outlet  20  may be provided instead of reservoir  14 , heater  16 , and conduits  18  and  22 . For example, outlet  20  may be connected directly to a hot water faucet. Outlet  20  is positioned above a contaminant remover  33  (not shown), e.g. a filtration medium. A supporting device  24  supports contaminant remover  33 . 
     Preferably, supporting device  24  is an annular structure (see FIG. 3D) having an outer wall  46  and an inner wall  48 . A ledge  50  extending inwardly from inner wall  48  is adapted to receive contaminant remover  33 . Inwardly-extending supports (not shown) may span the opening of annular structure  46  to underpin contaminant remover  33 . Such inwardly-extending supports may be disposed in any suitable pattern, such as a lattice. 
     Ledge  50  of supporting device  24  also preferably has a groove  56  adapted to receive frame  54 . Grove  56  and frame  54  may be designed so as to tightly mate and, thus, create a watertight seal. A watertight seal will ensure that all liquid directed to contaminant remover  33  will indeed pass therethrough. Likewise, since liquid may exit outlet  20  more quickly than it can pass through contaminant remover  33 , a reservoir, or reserve space, may be created above contaminant remover  33 . The capacity of the reservoir is defined by a distance d (see FIG.  3 E), which is between a top rim  51  of annular structure  46  and receiving ledge  50  (see FIG. 3D or  3 E), multiplied by the area of annular structure  46 . The areas of annular structure  46  and contaminant remover  33  should be made as large as reasonably possible within the practical constraints of the brewed beverage maker, while distance d should be configured to provide enough reserve capacity to prevent the overflow of liquid. Distance d will depend on the flow rate of water through contaminant removing medium  52  and the flow rate of liquid from outlet  20 . 
     Supporting device  24  is attached to housing  12  by an assembly, shown generally as  26 , which allows supporting device  24  to be disposed alternatively in an operative or inoperative position relative to outlet  20 . Preferably, supporting device  24  is removably attached to housing  12 . In the operative position, assembly  26  disposes supporting device  24  below outlet  20 . In the inoperative position, supporting device  24  may be accessed for the purpose of installing, cleaning, or replacing contaminant remover  33 . Preferred embodiments of assembly  26  are described below. 
     Furthermore, when supporting device  24  is in the operative position, a brew basket  28  may be positioned below supporting device  24 . Brew basket  28  may hold one or more brewing ingredients, such as coffee grounds, tea leaves, and/or spices. Preferably, brew basket  28  is removably attached to housing  12 . A collector  30 , typically a carafe, may be positioned below brew basket  28 . Like most commercially available beverage brewers, beverage brewing system  10  may be provided with a heating surface  32  upon which collector  30  may rest and whereby the collected beverage may be kept warm. 
     Referring to FIGS. 2A and 2B, supporting device  24  is illustrated with a first preferred embodiment of assembly  26 , hereinafter referred to generally as  26   a . Support assembly  26   a  is a hinge device having a first panel  27   a  connected to housing  12 , a second panel  27   b  connected to supporting device  24 , and a pivoting pin  27   c  joining the two panels  27   a ,  27   b  together. Assembly  26   a  permits supporting device  24  to be pivoted about pivoting pin  27   c  between the operative position, illustrated in FIG. 2A, which places contaminant remover  33  under outlet  20  and over brew basket  28  (as shown in FIG.  1 ), and the inoperative position, illustrated in FIG. 2B, which allows access to supporting device  24  and contaminant remover  33 . Since the various components of commercial beverage brewers are usually made from molded thermoplastic materials, panels  27   a ,  27   b  may be made integral to beverage brewing system  10 . Those skilled in the art will also appreciate that variations can be made to the materials and construction of the hinge components without deviating from the spirit of the invention. 
     FIGS. 3A through 3E illustrate a second preferred embodiment of assembly  26 , hereinafter referred to generally as  26   b . Assembly  26   b  is formed, in part, by a panel  34  having a near end  36  and a remote end  38 . Supporting device  24  is attached to remote end  38 . Panel  34  is slidingly supported in housing  12  by bearing surfaces  40   a ,  40   b , which are affixed to housing  12 . Alternatively, panel  34  may be releasably, slidingly received within said housing in a manner (not shown) resembling the way a cartridge in releasably, slidingly fastened within a base. A spring-like device (not shown) could be adapted to housing  12  for the purpose of ejecting panel  34  from housing  12 . Bearings  42   a ,  42   b  (see FIG. 3C) may be positioned between bearing surfaces  40   a ,  40   b  and near end  36  to reduce the sliding friction. Optionally, bearing surfaces  40   a ,  40   b  may be lubricated or made from a material which has a low coefficient of friction compared to the material forming panel  34 . Optionally, near end  36  has a large notch  44  provided therein so that panel  34  will not obstruct access to reservoir  14  or the flow of hot water in conduit  22  when panel  34  is in the operative position, as shown in FIG.  3 B. Supporting device  24  and panel  34  may be made as a single piece of molded thermoplastic. Alternatively, supporting device  24  and panel  34  may be constructed by other suitable methods, using other suitable materials known to the art, such as metal. 
     FIGS. 5A through 5D show a third embodiment of support assembly  26 , hereinafter referred to generally as  26   c . In this embodiment, support assembly  26   c  is a pair of telescoping arms  58   a ,  58   b  that permit supporting device  24  to slide between the inoperative position, illustrated in FIGS. 5A and 5B, and the operative position as illustrated in FIGS. 5C and 5D. Telescoping arms  58   a  and  58   b  each comprise four segments, shown respectively as  60   a - 60   d  and  62   a - 62   d . Of course, a greater or lesser number of arm segments can be used. First end segments  60   a  and  62   a  are connected to housing  12 , and second end segments  60   d  and  62   d  are connected to supporting device  24 . The remaining segments  60   b ,  60   c  and  62   b ,  62   c  are connected telescopically between their respective end segments. First end segments  60   a ,  62   a  and second end segments  60   d ,  62   d  can be integrally molded with housing  12  and supporting device  24 , respectively. 
     Referring to FIGS. 3D and 6A, there is illustrated a contaminant remover  33  for use with supporting device  24 . Contaminant remover  33  is preferably configured as a frame  54  supporting a filter medium  52  (see also FIG.  6 A). 
     Frame  54  is preferably injection molded around filter medium  52 . Consequently, frame  54  may be molded in numerous configurations. FIGS. 3D and 6A illustrate preferred configurations for frame  54 . As shown, frame  54  is an annular, peripheral rim with a plurality of inwardly extending members. These configurations resemble spoke and wheel arrangements with filter medium  52  held securely within. 
     Injection molding frame  54  around filter medium  52  involves, first, forming filter medium  52  as described below. Second, the periphery of filter medium  52  is hot stamped, which seals the edges of filter medium  52 . Filter medium  52  is then cut to shape and inserted into an injection molding machine. A thermoplastic material is then injected around filter medium  52 . Preferably, the thermoplastic material is polyethylene. It has been discovered that polyethylene offers a preferred balance between strength and flexibility. However, any thermoplastic material may be used. Hot stamping and cutting filter medium  52  may be accomplished in one integrated step, rather than two separate steps. 
     As stated above, filter frame  54  is adapted to rest upon receiving ledge  50  (see FIGS. 3D and 4A) when contaminant remover  33  is placed within supporting device  24 . Alternatively, filter frame  54  may be adapted to rest within a receiving notch, as illustrated in FIG.  4 B. Referring to FIG. 6B, frame  54  may also be provided with a downwardly-extending protrusion  53  designed to fit within a complementary groove (not shown) in receiving ledge  50 . Moreover, frame  54  may have an upwardly extending protrusion  59  adapted to mate with complementary groove  58  in another frame  54 . Thus, multiple frames may be stacked for packaging and display purposes. 
     Filter medium  52  is shown in FIG.  6 A. Filter medium  52  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. Preferably, filter medium  52  provides suitably high flow and minimal pressure drop, when liquid in passed therethrough. 
     As shown is FIG. 7A, filter medium  52  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 . 
     Filtration medium  52 , as illustrated in FIG. 7A, 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. 
     Materials such as iodinated resin, activated carbon, activated alumina, alumina-silicates, ion-exchange resins, and manganese or iron oxides can be used as adsorbent particles  74 . 
     Materials forming binder particles  76  typically include thermoplastics such polypropylene, linear low-density polyethylene, low density polyethylene and ethylene-vinyl acetate copolymer. 
     Referring to the embodiment in FIG. 7B, filter medium  52  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 . 
     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. 
     During the operation of beverage brewing system  10 , a liquid from liquid reservoir  14  flows through conduit  18  to heater  16 . The liquid is heated and then passes through conduit  22  to outlet  20 . After exiting outlet  20 , the heated liquid passes through contaminant remover  33 . Contaminant remover  33  removes contaminants, thereby creating a substantially pure, heated liquid. The substantially pure, heated liquid enters brew basket  28 . Therein, the substantially pure, heated liquid mixes with the brewing ingredients. The resulting brewed beverage exits brew basket  28 , enters collector  30 , and is optionally kept warm by heating surface  32 . 
     As can be seen from the foregoing detailed description and drawings, the present invention provides a beverage brewing system  10  that is adapted to hold contaminant remover  33  conveniently between outlet  20  and brew basket  28  permitting independent access to both contaminant remover  33 , which is contained within separate supporting device  24 , and brew basket  28 . Such access is made possible via support assembly  26 , which allows alternative movement between an operative position and an inoperative position. The user has convenient access to contaminant remover  33  when supporting device  24  is in the inoperative position. Thus, a user of beverage brewing system  10  may conveniently change contaminant remover  33  without interference from, or involvement with, brew basket  28 . In addition, contaminant remover  33  is less likely to be lost or damaged because, once installed, it becomes an integrated part of beverage brewing system  10 . Moreover, since contaminant remover  33  is not located within brew basket  28 , it is unlikely to be contaminated with brewing ingredients. 
     Although beverage brewing system  10  has been described with respect to one or more particular embodiments, it will be understood that other embodiments of the present invention may be employed without departing from the spirit and scope of the present invention. Hence, the present invention is deemed limited only by the appended claims and the reasonable interpretation thereof.