Abstract:
The invention provides an hourglass shaped apparatus for cold brewing coffee, comprising a brew chamber, and extract chamber and a middle unit connecting the brew and extract chambers. The extract and brew chambers comprise two ends of the hourglass shaped middle unit. The brew chamber houses a free-standing self-contained filter containing coffee grounds inside a water-permeable barrier. Water is poured into the brew chamber to generate coffee extract through cold water infusion. After the brewing process, the apparatus is inverted, and the coffee travels into the extract chamber through the middle unit for dispensing. Coffee brewed in this manner is less acidic and more flavorful than the conventionally hot-brewed beverage. All the components of the apparatus, the filter, the brew chamber, the extract chamber, and the middle unit, are detachable.

Description:
CLAIM OF PRIORITY 
     Pursuant to 35 U.S.C. §120, this application is a continuation-in-part of U.S. application Ser. No. 11/406,742 filed on Apr. 18, 2006, published on Oct. 19, 2006 as United States Publication No. 2006/0230944 A1, and issued as U.S. Pat. No. 7,858,133 on Dec. 28, 2010. U.S. application Ser. No. 11/406,742 claimed the benefit of U.S. Provisional Application No. 60/672,591, filed on Apr. 18, 2005. 
    
    
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention generally relates to an improved apparatus for brewing coffee and more particularly to an improved apparatus that cold brews coffee to produce an infusion of coffee extract, and also stores and dispenses coffee. 
     2. Description of Related Art 
     Apparatuses for brewing coffee are well known in the art. In the known art, coffee is customarily drip-brewed using heated water. Water is heated in a vessel, and then poured over a container of ground coffee. As the water mingles with the grounds, a coffee extract is produced which drips through a filter into a coffee pot or cup. Improvements to the art have led to machines that automatically heat water and brew coffee in one self-contained device. 
     Although coffee is traditionally brewed in hot or boiling water, it is also possible to cold brew coffee. A preference for cold brewed coffee has developed, principally due to its flavor. Since many of the bitter oils and acids contained in coffee are soluble only at high temperature, coffee brewed with hot or boiling water can be characterized by a harsh acid taste. Cold brewed coffee avoids this problem. As the preference for cold brewed coffee has grown, several developments in the cold brew process have been made. 
     U.S. Pat. No. 4,051,264 to Sanderson discloses a process for obtaining a cold water extract from tea leaves. The process involves treating fresh green tea leaves with an enzyme additive to produce dry tea leaves which are cold water extractable. In addition, U.S. Pat. No. 6,761,918 to Pulikkottil discloses a method of processing green tea leaves to produce black tea particles that can be brewed in cold water. 
     U.S. Pat. No. 2,878,746 discloses a cold water coffee brewer comprising a large canister into which coffee grounds are placed and through which cold water is circulated. The &#39;746 device is designed to infuse cold water with coffee similar to the present invention. However, it is structurally distinct, and achieves the infusion through a drip mechanism by forcing the aqueous solution up through a pipe and onto a series of foraminous shelves rather than separating the aqueous solution from the coffee grounds by inverting the entire apparatus. U.S. Pat. No. 4,112,830 discloses a similar device using cold water to obtain an extraction. This device is also structurally distinct from the present invention, complex and difficult to clean. 
     The aforementioned cold brewing methods and devices are either meant for brewing substances other than coffee, or they are structurally different from the present invention, and are designed for a different type of process. Therefore, it is an object of the present invention to provide an improved apparatus for cold brewing coffee to produce a liquid extract or infusion that can brew, store and dispense coffee. 
     A further object of the present invention is to provide an improved cold brew coffee apparatus that is fully invertible wherein the apparatus is of hourglass shape/design to facilitate brewing and dispensing. 
     A further object of the present invention is to provide an improved cold brew coffee apparatus wherein a unique coffee filter system is free standing and integrates into the brew chamber easily and with no mess. 
     Finally, it is an objective of the present invention is to provide an improved cold brew coffee apparatus which is a fully enclosed system, whereby coffee grounds are brewed in cold water for extended period of time for better taste and flavor and the resulting extract can be stored in a refrigerator for up to two weeks. These and other objects of the present invention will become better understood with reference to the appended Summary, Description, and Claims. 
     SUMMARY OF THE INVENTION 
     The present invention relates to an improved apparatus for brewing coffee to produce a liquid extract/concentrate that can be brewed in cold water and which can be stored fresh in the refrigerator for up to two weeks. The apparatus solves the inherent problems of hot brew methods that produce a bitter, acidic coffee, and improves the art of cold brewing. 
     The cold brew coffee apparatus comprises a filter or a filter assembly (used interchangeably herein as “filter” unless otherwise specified), a middle unit, a brew chamber and an extract chamber. 
     When a filter assembly is used, the filter assembly comprises an outer cup, a hollow inner housing and a water-permeable barrier secured between the outer cup and inner housing. The water-permeable barrier is exposed between the side walls of the outer cup and inner housing. 
     When a middle unit is present, it is hollow and comprises two conical extremities connected by a narrow midsection. 
     The extract chamber is the same size as the brew chamber, and is mounted to the end of the middle unit, when present, opposite the brew chamber. 
     To brew coffee, the filter is securely placed on a flat surface on its base and filled with coffee grounds. The brew chamber is then inverted so that its open end fits over the filter. The brew chamber is securely pressed onto the rim of the filter forming a hermetic seal between the brew chamber and the filter. The brew chamber having the secured filter is again inverted and made to stand on its base so that the filter assembly is upside-down. 
     The brew chamber having the secured filter with coffee grounds is then filled with water thereby soaking the coffee grounds. Different amounts of water can be added to achieve either a more concentrated or less concentrated extract. 
     If using an embodiment with a middle unit, it is attached by engaging threading at the junction of the brew chamber and the middle unit. The extract chamber is then mounted to an opposite end of the middle unit. A gasket or an o-ring on the threading prevents leakage between the brew/extract chambers and the middle unit. Other embodiments include attaching a middle unit using a snapping mechanism or other leak-proof mechanism of joining the middle unit to the brew/extract chambers. 
     The apparatus is then left to brew, resting securely on the base of the brew chamber. After the proper level of infusion is reached, usually after twelve to twenty-four hours, the brew cycle is complete. The concentration of the coffee extract is time dependent (e.g. a longer brewing time results in a more concentrated extract). 
     The apparatus is then inverted, and the cold brewed coffee extract is filtered through the filter and into the extract chamber. Once the coffee has drained from the brew chamber, the brew chamber and filter are disassembled and the coffee grounds are disposed. Any cold brewed coffee extract that is not immediately used can be decanted from the extract chamber into a storage container. The storage container may be refrigerated for up to two weeks. The filter, the middle unit and brew and extract chambers can then be cleaned for re-use. 
     Cold brewed coffee is more concentrated and less acidic than conventionally brewed coffee. To approximate the characteristics of a typical cup of coffee, the cold brewed coffee extract can be diluted with hot water. According to preference, it may also be consumed at a higher concentration, used to prepare an iced beverage or for cooking. 
     In one preferred embodiment of the invention, the main structural components are composed of acrylic or polycarbonate. In addition, all of the parts of the apparatus are reusable. 
     These and other features and advantages of this invention are described in, or are apparent from, the following detailed description of various exemplary embodiments of the apparatus and methods according to this invention. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a perspective view of a cold brew coffee apparatus in accordance with the present invention. 
         FIG. 2  is perspective view of one embodiment of the filter comprising an extruded frame encasing a water-permeable barrier. 
         FIG. 3  is a perspective view of the filter of the cold brew coffee apparatus of the present invention. 
         FIGS. 4A ,  4 B and  4 C are different views of the outer cup of an embodiment of the filter comprising a filter assembly. 
         FIGS. 5A and 5B  are perspective views of the inner cup of an embodiment of the filter comprising a filter assembly. 
         FIG. 6  is a perspective view of an embodiment of the coffee filter comprising a filter assembly. 
         FIGS. 7A and 7B  are perspective views of brew/extract chamber. 
         FIG. 8  is a perspective view of the brew chamber with the filter. 
         FIGS. 9A and 9B  are perspective views of the bases with gripping pads. 
         FIGS. 10A and 10B  are perspective views of the middle unit. 
         FIG. 11  is a perspective view of the carafe assembly. 
         FIG. 12  is a front view of the cold brew coffee apparatus of the present invention, fully assembled and standing on the brew chamber. 
         FIG. 13  is a front view of the cold brew coffee apparatus of the present invention, fully assembled and standing on the extract chamber to collect the coffee. 
         FIG. 14  is a box diagram explaining how to use the apparatus. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     The novel features of the present invention will become apparent from the following description of the preferred embodiment, and as illustrated in  FIGS. 1 through 14 . One embodiment of the claimed invention is an hourglass-shaped cold brew coffee apparatus  10 , which comprises a filter  11 ,  41  a brew chamber  12 , and a carafe assembly  13 . The carafe assembly  13  is comprised of a middle unit  14  and an extract chamber  15 . The cold brew coffee apparatus may comprise other shapes and designs for the middle unit  14 , brew chamber  12  and extract chamber  15 . 
     Referring to  FIG. 2 , the filter may comprise an extruded frame  44  encasing a water-permeable barrier  43  having a gasket  42  attached to the rim to form a hermetic seal between the inner volume of the filter and the inner volume of the brew chamber. The extruded frame further comprises a substantially flat surface having four leg members  22  to form a base opposite the rim. The leg members  22  act as feet to form a base for the filter as ground coffee is placed into the inner volume of the filter. The extruded frame  44  may be comprised of plastic, aluminum or other non-corrosive material. The water-permeable barrier  43  may be comprised of a variety of materials including plastic, wire mesh or laser cut metal. 
     The interior of the bottom surface of the brew chamber  12  includes a cylindrical depression  32  that is adapted to receive the gasket  42  of the filter  41 . The gasket  42  achieves a hermetic seal between the filter and the brew chamber  12  when the filter is inverted, placed inside the brew chamber and pressure is applied to the flat surface  45  or legs  22  of the filter  41  pushing the filter into the cylindrical depression in the brew chamber  32 . 
     The filter may also comprise an assembly of parts. Referring to  FIGS. 3 through 6 , the filter assembly  11  includes an outer cup  16 , an inner housing  17  and a micro-fine wire mesh or other water-permeable barrier  18  that filters out coffee extract from the coffee grounds. The outer cup&#39;s structure comprises a substantially flat surface  19  and a rim  20  opposite and connected to the flat surface  19  by four connecting members  21 , which leave four large openings in its side walls. Four leg members  22  on the flat surface  19  of the outer cup  16  serve as feet to support the filter assembly  11  on any flat surface as the filter assembly is filled with coffee grounds. The inner housing&#39;s  17  structure comprises a first rim  23  and a second rim  24  connected to the first rim  23  by four connecting members  25 , which also leave four large openings in its side walls. The second rim  24  projects outwardly from the exterior of the inner housing  17 . The water-permeable barrier  18  is secured between the outer cup  16  and inner housing  17  so that it is exposed from between their connecting members  21  and  25 , thereby enabling the coffee extract to pass through. 
     The side walls of the outer cup  16  are slightly sloped towards the flat surface  19  and the side walls of the inner housing  17  are slightly sloped towards the first rim  23 , so that the inner housing is telescopically received in the outer cup. In addition, the external dimensions of the inner housing  17  are substantially equal to the internal dimensions of the outer cup  16 , leaving a small clearance between them to firmly accommodate the water-permeable barrier  18 . The outer cup  16  includes three holes  26  around the periphery of its flat surface  19  and a projecting section  27 , which radially projects downwards from the flat surface  19 . The projecting section  27  extends into one of the connecting members and forms a groove  28  on top of the flat surface  19 . The groove  28  channels water into the brew chamber to soak the grounds. The interior of the flat surface  19  includes a radially oriented groove (not shown) for receiving the first rim  23  of the inner housing  17 . The first rim  23  includes three projecting members  29  and a groove  30  on one of the connecting members. The projecting members  29  are suitably designed to snap into the holes  26  of the outer cup  16 . 
     In order to secure the inner housing  17  inside the outer cup  16 , the projecting section  27  is received in the groove  30  of the inner housing and the projecting members  29  are snapped into the holes  26  of the outer cup, by pushing the inner housing inside the outer cup. But, first the water-permeable barrier  18  is wrapped around the inner housing  17  before it is secured inside the outer cup  16 . A gasket  31  or an o-ring is placed between the rim  20  of the outer cup and the second rim  24  of the inner housing. The interior of the bottom surface of the brew chamber  12  includes a cylindrical depression  32  that is adapted to receive the second rim  24  of the inner housing  17 . The gasket  31  placed between the rim  20  of the outer cup and the second rim  24  of the inner housing helps in achieving a secure fit between the filter  11  and the brew chamber  12 . 
     Referring to  FIGS. 7 and 8 , the brew and extract chambers  12  and  15  are identical and constitute approximately one fourth the size of the whole apparatus  10 , representing the ends of the middle unit  14 . The interior of the bottom surface of the brew and extract chambers  12  and  15  includes a cylindrical depression  32  to receive the gasket  21 ,  42  of the filter forming a hermetic seal. 
     Referring to  FIGS. 9A and 9B , a first base  33 A is attached to the brew chamber  12 . The cylindrical depression  32  in the interior of the brew chamber leads to a cylindrical projection on its exterior bottom surface. The first base  33 A is adapted to be firmly attached over the cylindrical projection. A second base  33 B, similar to the first base  33 A, is attached to the bottom of the extract chamber  15 . Several designs and structures are possible for the bases, one of them being shown in  FIGS. 9A and 9B . The bases further include a plurality of gripping pads  34  made of rubber or other anti-slip materials. The center portion of the bases may include a removable disc  39 , which can be snapped into the indentation in the base  40 . Even the gripping pads can be snapped onto the bases. The removable disc  39  may be marked with a trademark, logo or other design. 
     Referring to  FIGS. 10A and 10B , the middle unit  14  is hollow to allow the passage of liquid. One example of the middle unit comprises two conical members  35 A and  35 B connected at their vertices. The middle unit  14  is approximately half the size of the apparatus  10 . The inner surface of the conical members includes pouring structures  38 . The brew and extract chambers include helical threaded indentation on the exterior of their mouths  36 , which are adapted to engage a complimentary set of threaded indentation on the inner surfaces of the two ends  37  of the middle unit  14 . A gasket is used to form a hermetic seal at the junction of the middle unit  14  and the brew/extract chambers. The middle unit  14 , along with the brew and extract chambers  12  and  15  mounted to its either ends, is designed to conform to an hourglass shape. Other shapes that allow the passage of liquid between the brew and extract chambers are also contemplated. 
     Referring to  FIG. 14 , in order to use the apparatus, first, obtain ground coffee beans either by purchasing pre-ground beans or grinding whole beans  200 . Detach the brew chamber  12  from the middle unit  14  and the filter  11 ,  41  is removed and set aside the extract chamber  15  still mounted to the opposite end of the middle unit  37 B. Approximately two cups of fresh coffee grounds are then placed in the filter which is stabilized and supported by the leg members  22  with the open end up exposing the inner volume  210 . The brew chamber  12  with its associated base  33 A is inverted  220  so that its open end is fitted over the filter  11 ,  41 , in a downward motion sealing in place the gasket  31 ,  42  using pressure to engage the gasket with the cylindrical depression in the brew chamber. The inner volume of the filter  11 ,  41  thereby encloses the coffee grounds and forming a hermetic seal between the gasket  31 ,  42  and the brew chamber  220 . The brew chamber  12 , now engaged with the filter  11 ,  41 , is then inverted again so the first base  33 A is down and the leg members  22  of the filter  11 ,  41  are facing up  230  exposing the open top of the brew chamber. Add cold water (room temperature or colder) or other brewing liquid to the open top of the brew chamber containing the filter with ground coffee  240 . Add sufficient liquid to cover the grounds without overflowing  240 . One of the ends  37 A of the middle unit is mounted to the brew chamber  250  secured to an inverted filter with coffee. The apparatus  10  now stands on the brew chamber  12 , particularly on the first base  33 A attached to the brew chamber  12 , as seen in  FIG. 12 . The gaskets between each base and the middle unit prevent leakage after the apparatus is assembled. Water soaks into the grounds and starts the cold brew infusion process. The brewing process takes approximately twelve to twenty-four hours at room temperature although brewing may occur at lower temperatures not to exceed freezing  260 . 
     After the brew cycle is complete, invert the brewing apparatus  10  to stand on the extract chamber  15 , allowing the soluble coffee extract to pass through the filter and middle unit and accumulate in the extract chamber  270 , as seen in  FIG. 13 . The cold brewed coffee extract then drains out of the filter  41  and the brew chamber  12 , and into the extract chamber  15  through the middle unit  14 ,  270 . The apparatus  10  takes approximately five minutes to complete this step. After all the extract has drained into the extract chamber  15 , the brew chamber  12  and filter  11 ,  41  are disconnected and the coffee grounds are disposed of. The coffee extract is then decanted from the extract chamber  15  using the pouring structures  38  located on the inner surface of the middle unit  280 . The coffee extract can be poured into a storage container and can be kept fresh under refrigeration for up to two weeks  300 . Once the coffee has been dispensed, the entire apparatus can be disassembled and cleaned. 
     Coffee brewed in the apparatus  10  is a deep rich extract coffee concentrate, and is far less acidic than conventionally brewed coffee. It can be diluted with hot water to a desired taste and strength  290 . To make a typical cup of coffee, two tablespoons of extract are added to 8 oz of hot water. More or less concentrate can be added for desired taste and strength. In one preferred embodiment of the invention, the brew chamber, the extract chamber, and the middle unit of the apparatus are made of acrylic or polycarbonate material. Other materials may be used, however, including glass, metal and other forms of plastic. 
     The features disclosed in this specification, including any accompanying claims, abstract, and drawings, may be replaced by alternative features serving the same, equivalent or similar purpose, unless expressly stated otherwise. Thus, unless expressly stated otherwise, each feature disclosed is one example only of a generic series of equivalent or similar features. 
     While specific apparatus has been disclosed in the preceding description, it should be understood that these specifics have been given for the purpose of disclosing the principles of the present invention and that many variations thereof will become apparent to those who are versed in the art. Therefore, the scope of the present invention is to be determined by the appended claims. 
     Any element in a claim that does not explicitly state “means for” performing a specified function, or “step for” performing a specific function, is not to be interpreted as a “means” or “step” clause as specified in 35 U.S.C. §112, paragraph 6. In particular, the use of “step of” in the claims herein is not intended to invoke the provisions of 35 U.S.C. §112, paragraph 6. 
     While this invention has been described in conjunction with the specific embodiments outlined above, it is evident that many alternatives, modifications and variations will be apparent to those skilled in the art. Accordingly, the preferred embodiments of the invention, as set forth above, are intended to be illustrative, not limiting. Various changes may be made without departing from the spirit and scope of this invention.