Patent Abstract:
A beverage brewer ( 20 ) with a programmable dispenser cycle dispenser valve controller ( 36 ) for controlling a dispenser valve ( 34 ) to intermittently open and close during a plurality of control periods of an intermittent dispense period ( 88 ) to selectively control the quantity of hot water that is dispensed without changing the overall duration of the dispense period ( 88 ). Each of the control periods (CP 1 -CP 20 ) has a duty portion during which the dispenser valve is open that is selectively varied to brew either greater or lesser amounts of beverage without varying the overall dispense period ( 88 ). Alternatively, the number of control periods is selectively changed to change the overall dispense period ( 88 ) without changing the quantity of beverage by appropriate changes to the duty portion. The quality of the resulting beverage is thereby optimized by controlling both the time of contact of the hot water with the beverage ingredient ( 70 ) and the amount of hot water that is mixed with a given amount of ingredient ( 70 ). Uniform contact of the hot water with the beverage ingredient ( 70 ) is enhanced by a uniform ingredient holder ( 24 ) That holds the ingredient in a tubular configuration beneath a uniform flow dispenser head ( 38 ) that pulses the top of the tubular configuration with a uniform spray.

Full Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
     This application is a division of application Ser. No. 09/131,992 filed Aug. 11, 1998, now U.S. Pat. No. 6,148,717 issued Nov. 21, 2000 to the present inventor, and claims the benefit of the earlier filing date of this application under 35U.S.C. 120. 
    
    
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     This invention generally relates to beverage brewers, and methods of brewing and, more particularly, to beverage brewers and methods of brewing in which the quantity of brewing liquid that is delivered to the brewing ingredient and the time period during which the brewing liquid is dispensed into a brewing ingredient holder is automatically controlled, and to beverage ingredient filters in which the ingredient is contained during brewing. 
     2. Discussion of the Relevant Prior Art 
     The inventor has determined that there is a common problem associated with all commercial beverage brewers of the drip-type in which the brew liquid is passed through brewing ingredient. The brewing ingredient is ground coffee, ground tea, tea leaves and other like dry beverage ingredients. The beverage brewing liquid is generally plain hot water. The brew ingredients have a residue or structure that contains the essential dry beverage components. When the beverage brewing liquid that is passed through a layer of the dry beverage ingredient during the dispensing period of the brewing cycle and the post-dispense drip period, the dry beverage ingredients are dissolved and released into the beverage brewing liquid upon contact. The brewing ingredient is generally contained within a removable filter that is supported within a brew basket that is movably mounted beneath a brewing liquid dispenser, or dispenser, to receive the hot brewing water. The filter is manually loaded with beverage ingredient and then placed in a filter holder within the brew basket. Each of the brew basket and the filter holder has a generally truncated conical shape with sides that slope inwardly from the open top of the brew basket to the beverage dispenser outlet that is located at the bottom of the brew basket. 
     The problem with this arrangement is that it is not possible to obtain a uniform contact of the hot brewing water with the ingredient within the brew basket during the dispensing period while the hot water is being dispensed and the subsequent post-dispensing drip period of the brew cycle. In the case of ground coffee, when hot water first makes contact with the coffee gases are generated that causes the coffee grounds to foam upwardly and also to float layers of hot water that have not yet seeped through the upper surface of the layer of hot coffee. 
     The inventor believes that for this reason and because of the generally conical shape of the layer of beverage ingredient, and despite continuous spraying of the hot brewing water across the upper surface of the beverage ingredient, some of the ingredient, generally nearer the side walls of the brew basket, does not receive sufficient contact with the hot water to strip off all the beverage ingredient component to be dissolved into the water that is being held by the beverage ingredient. The beverage ingredient is therefore wasted. Likewise, other portions of the beverage ingredient, generally closer to the central portion of the brew basket receive too much contact with the hot water, ie. more contact with the water than needed to dissolve all the beverage ingredient components, and other undesirable ingredient components are dissolved into the brewed beverage. Consequently, optimum brewing of the beverage ingredient is not obtained and the brewing ingredient component that does not dissolve into the hot water because of insufficient hot water contact with the associated brewing ingredient is wasted. 
     Both the time of contact of the hot water with the beverage ingredient and the amount of hot water that is mixed with a given amount of beverage are critical to optimizing the quality of the resulting brewed beverage. Different types of beverage ingredient, such as different types of coffee, and different forms of a given beverage ingredient, such as a given ground coffee of different degrees of coarseness require different amounts of hot water for optimum brewing of the resulting beverage. Unfortunately, there is another problem of known beverage brewers which exacerbates the nonuniform ingredient saturation problem noted above. The problem is the inability to easily adjust the quantity of hot water that is dispensed without changing the duration of the dispensing time period, and the inability to easily adjust the duration of the dispense period without changing the quantity of hot water that is to be dispensed. 
     The truncated conical shape of know beverage ingredient filters precludes them from being easily stacked or packaged and accordingly in all known commercial drip-type brewers the conical filters are manually loaded with ingredient at the coffee brewing site. 
     Reference should be made to U.S. Pat. No. 5,000,082 entitled “Beverage Maker And Method Of Making Beverage” issued Mar. 19, 1991 and U.S. Pat. No. 5,331,885 entitled “Semiautomatic Beverage Maker And Method” issued Jul. 26, 1994 of the present inventor and the patents cited therein, all of which are incorporated herein by reference, for structural, mechanical and other details of the conventional components of coffee brewers and the like, with reference to the features noted above, and in general with reference to the embodiments described below to the extent conventional elements are disclosed in functional block form only and such details are desired. 
     In U.S. Pat. No. 5,375,508 issued to Knepler et al ofn Dec. 27, 1994 for a “Digital Brewer Control” mechanisms are shown that enable intermittent dispensing of the hot water Into the brew basket. However, this is done solely to slow down the average rate of dispensing, or infusion, of the water into the brew basket to prevent overflowing the brew basket. Such overflowing occurs during continuous dispensing under the special circumstances of decaffeinated coffee and soft water that reduces the rate of outflow from the brew basket. However, there is nothing to suggest using such intermittent flow for purposes of obtaining uniform extraction when dealing with different amounts or different types of coffee. 
     SUMMARY OF THE INVENTION 
     Accordingly, it is the primary object of the present invention to provide a beverage brewer and a method of brewing in which the aforementioned problems of known beverage brewers and brewing methods are overcome. 
     This objective is achieved in part by providing a beverage brewer with a beverage ingredient holder; and a dispenser assembly with means for automatically, intermittently, delivering brewing liquid into the beverage ingredient holder during a dispensing period of a brewing cycle. Preferably the the dispenser assembly includes a dispenser valve, and a dispenser valve controller to control the valve for automatically, intermittently, delivering the brewing liquid into the beverage ingredient holder during the dispensing period of the brewing cycle. 
     Preferably, the dispenser valve controller includes means for dividing the dispersing period into a plurality of dispensing control periods, means for establishing a duty portion for at least some of the plurality of dispensing control periods, and means for actuating the dispensing valve to pass the brewing liquid to the beverage ingredient holder only during the preselected duty portion of each of the plurality of dispensing control periods. 
     The duty portion establishing means includes means for selectively controlling the duration of the duty portion the plurality of dispensing control periods. Different duty portions for different dispensing control periods of the same dispensing period are established to selectively vary the average flow rate at different segments of the dispensing period. The duty portion controlling means includes means for increasing the duty portion of each successive dispensing control period occurring during the dispensing period. The duty portion controlling means also preferably includes means for decreasing the duty period of each successive dispensing control period occurring during the dispensing period. Preferably, the dispenser assembly includes a computer that is programmed to control intermittent delivery of the brewing liquid to the beverage ingredient holder. 
     In keeping with another aspect of the present invention, the beverage ingredient holder has a brewing liquid receiving opening, and the dispenser includes a dispenser head assembly with a field of substantially uniformly spaced apart dispensing holes of substantially the same size located in coextensive overlying relationship with respect to the brewing liquid receiving inlet opening of the beverage ingredient holder and the beverage ingredient holder has a portion for supporting all of the ingredient in a substantially straight tubular configuration with spaced parallel upper and lower surfaces substantially entirely overlain by the field of dispensing holes. Preferably, the ingredient support surface is circular and the straight tubular configuration of the ingredient portion of the beverage ingredient holder is substantially cylindrical. 
     In accordance with another feature of the beverage brewer of the invention, the beverage brewer has a dispenser head assembly with a substantially closed body with a field of dispenser holes defining a bottom of the body and a top wall spaced oppositely from the field of dispenser holes supporting a brewing liquid inlet. A stream deflector is mounted in a blocking position between the brewing liquid inlet and the field of dispenser holes to reduce any uneven pressurization of the field of holes. A dispenser valve is periodically opened to intermittently fill the dispenser head body with brewing liquid and to uniformly force the brewing liquid out of all the dispenser holes under a uniform pressure. 
     Another advantageous feature of the invention is that the dispenser valve controller includes means for preselecting a length of time for the dispensing period, and means for selectively varying the total amount of brewing liquid delivered to the ingredient holder during the dispensing period of preselected length by varying the duration the intermittent periods of delivery during the dispensing period of the brewing cycle. Preferably, the intermittently delivering means includes means for dividing the dispensing period into a plurality of control periods each having a duration on the order of fifteen seconds, and means for delivering brewing liquid during a portion of each of the control periods during the dispensing cycle. Preferably, the valve controller is a computer. 
     In accordance with another aspect of the invention, a beverage ingredient assembly is provided having a tubular mass of beverage ingredient configured into a tube having parallel side walls joined at opposite ends to a continuous planer top and a continuous planer bottom that are parallel to each other and substantially perpendicular to and continuously spanning the parallel side walls and a disposable water and beverage permeable filter envelope snugly enclosing the tubular mass. Preferably, the tubular mass is configured as a solid cylinder, and the permeable filter envelope is made of filter paper. The proper tubular shape of the beverage ingredient is thereby maintained while the loading of the filters is capable of being performed on an automated basis and then the beverage ingredient assemblies packaged in a vacuum container in a stacked relationship which is not easily done with truncated conical shapes of the known brewers. 
     In accordance with one aspect of the brewing method of the present invention independent control of the dispense period and the total brewing liquid dispensed by preselecting a dispense time period of a brewing cycle during which brewing liquid is dispensed onto a top of a beverage ingredient layer and automatically selecting a number of control periods during which beverage liquid is capable of being dispensed onto a top surface of the beverage ingredient layer in accordance with the dispense time period that has been selected and dispensing the brewing liquid onto the top surface during at least some of the number of control periods that have been selected. The duty portion of at least some of the control periods during which the brewing liquid is dispensed onto the top of the beverage ingredient layer is changed in indirect relationship to any change in the number of control periods selected to substantially fix a preselected total amount of brewing liquid dispensed during different preselected dispense time periods. 
     Likewise, the method includes the steps o preselecting a total amount to be dispensed during a dispense period composed of a plurality of control periods of a brewing cycle during which brewing liquid is capable of being dispensed onto a top of a beverage ingredient layer, automatically selecting a duty portion of at least some of the plurality of control periods during which the brewing liquid is capable of being dispensed onto a top surface of the beverage ingredient layer of at least some of the control periods in accordance with the total amount to be dispensed that has been preselected, and dispensing the brewing liquid onto the top surface during the duty portions of the control periods that have been selected. The duty portion of at least some of the control periods during which the brewing liquid is dispensed onto the top of the beverage ingredient layer is directly controlled in indirect relationship to any change in the number of control periods selected to substantially maintain the preselected total amount of brewing liquid to be dispensed. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The foregoing advantageous features of the invention will be described in greater detail and other advantageous features of the invention will be made apparent from the following detailed description of the preferred embodiment of the beverage brewer of the present invention that is given with reference to the several figures of the drawing, in which: 
     FIG. 1 is a functional block diagram of the beverage brewer constructed in accordance with the present invention; 
     FIG. 2 is a functional block diagram of the preferred form of the dispenser valve controller shown as a single functional block diagram in FIG. 1; 
     FIG. 3A is a side view, partially in cross section, of the uniform flow dispenser head of the dispenser valve assembly shown in functional block form of FIG. 1 in operative relationship with the open top of a preferred form of the tubular ingredient holder shown in FIGS. 3A and 3B; 
     FIG. 3B is a plan view of the uniform flow dispenser head of FIG. 3A; 
     FIG. 4A is a side view, partially in cross section, of the preferred form of the tubular ingredient holder of FIG. 1 containing a layer of brewing ingredient in operative relationship with the uniform flow dispenser head of FIGS. 3A and 3B; 
     FIG. 4B is a plan view of the tubular ingredient holder of FIG. 4A; 
     FIG. 4C is a side elevational view, partially in section, of a cylindrical embodiment of the beverage ingredient assembly constructed in accordance with the present invention; 
     FIG. 4D is a cross sectional, side elevational view of a vacuum container of a plurality of substantially identical beverage ingredient assemblies like that of FIG. 4C packaged for shipping and storage. 
     FIGS. 5A and 5B are time charts with broken time lines illustrating the preferred brew cycle of the brewing method of the invention with an intermittent dispense period, and the dispenser valve control periods, respectively; 
     FIGS. 6A,  6 B and  6 C are time charts with broken lines illustrating three different modes of intermittent operation of the dispenser valve in which the on portion, or duty portion, of each of the successive control periods during the dispense period remain the same 50%, increase over time from 20% to 80% and decrease over time from 100% to 20%, respectively; 
     FIGS. 7A and 7B form a composite general logic flow chart of a computer program stored in the program memory of the dispenser valve controller of FIG. 2 for operating the beverage brewer of FIG. 1 to achieve the operation shown in FIGS. 5A,  5 B,  6 A,  6 B and  6 C and otherwise to perform operations of the beverage brewer in accordance with the brewing method of the invention; 
     FIG. 8 is a logic flowchart of the user program mode subroutine of FIG. 7 that enables the user to selectively program the brewer to operate in accordance with different user selectable brewing parameters; 
     FIG. 9 is a logic flow chart of the brew cycle dispenser valve control subroutine of FIG. 7 that controls the dispenser valve of FIG. 1 to achieve intermittent dispensing in accordance with the user inputs entered pursuant to the user program mode subroutine as well as in accordance with programmable default presets. 
    
    
     DETAILED DESCRIPTION 
     Referring to FIG. 1, the preferred embodiment of the programmable uniform flow beverage brewer  20  includes a programmable uniform flow dispenser assembly  22  that dispenses brewing liquid, generally hot water without any additives and therefore sometimes referred to simply as the hot water, uniformly across a quantity of beverage ingredient, generally ground coffee, ground tea, tea leaves and the like, contained in an opened top uniform flow ingredient holder  24  via a plurality of pulsed, or intermittent, streams  26  of hot water. The hot water makes uniform contact with the beverage ingredient within the uniform flow ingredient holder and then passes into a brewed beverage container  28 , such as a movable insulated serving urn. The programmable uniform flow dispenser assembly  22  includes a brewing liquid supply  30  containing a quantity of hot water sufficient for several brew cycles for the maximum quantity of beverage per brew cycle capable of being brewed by the brewer  10 . The brewing liquid supply  30  has an open outlet  32  to a dispenser valve  34  that is controlled by a programmable dispenser cycle-dispenser valve controller, or dispenser valve controller,  36  to intermittently deliver the hot water from the outlet  32  to a uniform flow dispenser head  38 . The dispenser valve  34  operates in accordance with a dispenser valve control signal generated on an output  37  of the dispenser valve controller  36  and applied to a control input  33  of the dispenser valve  34 . The uniform flow dispenser head  38 , in turn, delivers the intermittent streams  26  of hot water uniformly across the portion of an open top  40  of the uniform ingredient holder  24  vertically aligned with the entire top surface of the beverage ingredient contained within the uniform flow ingredient holder  24 . 
     The uniform flow ingredient holder  24  holds the ingredient in a laterally uniform cross-sectional, tubular form, preferably a cylindrical form, in order to obtain a uniform contact of the hot water with the beverage ingredient laterally across the surface of the beverage ingredient and most importantly across ensuing layers of the beverage ingredient through to the lowest layer of beverage ingredient at the bottom of the beverage ingredient layer. 
     The uniform contact is achieved primarily by virtue of the tubular layer of the beverage ingredient that is shaped into the tubular configuration by the uniform flow ingredient holder  24 . On the other hand, control of the dispenser cycle is primarily achieved by virtue of the controlled intermittent passage of the hot water to the uniform flow dispenser head  38 . 
     The fact that the passage of hot water is only intermittent enables the rate of flow of the dispensing holes of the uniform flow dispenser head to be controlled independently of the size of the holes. In accordance with the present invention optimum sized dispensing holes are used that are sufficiently large to avoid clogging due to calcification and the like while being sufficiently small to enable uniform flow across the surface of the Ingredient layer. 
     Referring now to FIG. 2, the dispenser valve controller  36  preferably includes a microprocessor  42  which generates a valve control signal on an output terminal  44  that is applied to a dispenser valve interface circuit  46 . The dispenser valve interface circuit amplifies the valve control signal to produce the dispenser valve control signal produced on the output terminal  37  and applied to the control input  33  of the dispenser valve  34 , FIG.  1 . The microprocessor  42  generates the valve control signal in accordance with a software program stored in a program memory  48 , described in detail below with respect to FIG. 7, and presets and other parameters stored in a data memory  50 . The microprocessor  42  also receives inputs through a manual input interface  52  from a keyboard  54  and input switches  56 . The microprocessor  42  also provides input control signals to various status indicators (not shown) through a status indicator interface  58 . 
     Referring to FIGS. 3A and 3B, the preferred form of the uniform flow dispenser head  38  is a closed cylindrical cavity  59  defined by a cylindrical side wall  60  extending between a closed top  62  that carries the central inlet  32  for receipt of the hot water from the brewing liquid supply  30  and a perforated bottom  64 . The perforated bottom has a field, preferably a uniform matrix, of dispenser holes  65  for uniform dispensing of the hot water onto the top surface of the layer of ingredient within the uniform flow ingredient holder  24 . Located between an opening  66  of the inlet  32  and the perforated bottom  64  is a conical deflector  68  to block the initial incoming rush of hot water from impinging directly upon and thereby unevenly pressurizing the dispenser holes  65  located directly opposite the inlet opening  66 . 
     In accordance with the preferred method of operation of the brewer  20 , the inrush of hot water under the force of the head pressure of the hot water contained within the brewing liquid supply  30 , rapidly fills the cavity  59  and thereafter the hot water is dispensed through the plurality of dispenser holes  65  at a uniform head pressure for the remainder of the open portion of the control period. The volume of the cavity  59  is of course only a small portion of the total volume of beverage to be brewed and of the volume of the brewed beverage container  28 . 
     Preferably, in the case of making several gallons of brewed beverage per brew cycle, the uniform flow dispenser head has a diameter and the cylindrical side wall  60  has a height to provide the a volume of only a fraction of a gallon. The inlet opening  66  and the head pressure provides an initial flow rate into the uniform dispenser head  38  to fill the cavity  59  within less than a second at the start of each control period. Thereafter, once the cavity  59  is filled, back pressure is encountered, and the flow rate is determined by the number and size of the plurality of dispenser holes  65 . The greater the number of and the smaller the size of the dispenser holes, the more uniform will be the flow across the top surface of the ingredient layer. However, the inventor has determined that in order to minimize clogging problems the dispenser holes  65  should not be too small. On the other hand, the inventor has determined in order to obtain optimum control over the flow rate by virtue of the intermittent dispensing of the hot water during a significant portion of each of the control periods, the dispensing holes should not be too big. 
     Referring to FIGS. 4A and 4B, the uniform ingredient holder  24  holds a tubular layer of ingredient  70  beneath the perforated bottom  64  of the uniform ingredient holder  38  for uniform receipt across its top surface  72  of the hot water being dispensed. Preferably, the uniform ingredient holder  24  has an open top  73  that is coextensive with both the perforated bottom  64  and the top surface  72  of the layer of ingredient  70 . Preferably, a bottom  74  of the layer of ingredient  70  is uniformly supported by an ingredient support screen  76  that supports the ingredient while allowing the free flow of brewed beverage downwardly into an inwardly tapered drainage section  78  located beneath the ingredient support screen  76 . The bottom of the tapered drainage section terminates with a central brewed beverage drain opening  80 . Preferably, the uniform flow ingredient holder  24  has a cylindrical side wall  82  extending between the open top  73  and the inwardly tapered drainage section  78 . In such case the tapered section has a conical wall that extends between the cylindrical wall  82  and the drain opening  80 , and the layer of ingredient  70  is supported in a cylindrical shape by the portion of the cylindrical adjacent and above the ingredient support screen  76 . 
     Referring now to FIG. 4C, an embodiment of a beverage ingredient assembly  81  of the present invention is seen in which the mass of beverage of the ingredient layer  70  is maintained in a tubular configuration, preferably a solid cylindrical configuration, having a cylindrical side wall  83 . The cylindrical side wall is joined at opposite ends to a continuous, planer circular top  87  and a continuous planer circular bottom  89  that are parallel to each other and substantially perpendicular to and continuously spanning the cylindrical side wall  83 . The ingredient layer  70  is supported in the cylindrical configuration by means of a disposable water and beverage permeable filter envelope  91  having a conforming cylindrical shape and snugly enclosing the tubular mass  70 . The filter envelope is preferably flexible, permeable filter paper that is disposable. The enveloped tubular mass of ingredient  70  is preferably one of ground coffee, or tea, preferably ground coffee. The filter envelope  91  has a top  93  and a bottom  101 , also made of filter paper, in which case the envelope is closed to prevent loss by spillage of any of the beverage ingredient  70 . Alternatively, the envelope top  93  is absent, as is explained with reference to FIG. 4D, below, either before or after shipping. With the top  93  present, the brewing liquid passes through the permeable top  93  to reach the top  87  of the mass of ingredient  70 . 
     Referring to FIG. 4D, an embodiment of a beverage ingredient assembly shipping and storage container  95  is shown in which a plurality of beverage ingredient assemblies  70 A,  70 B and  70 C, that are substantially identical to the beverage ingredient assembly  91 , are vacuum packed in stacked relationship in a snugly conforming vacuum container  97 . Preferably, the vacuum container  97  is a metal or air impervious plastic, cylindrical container with a removable top  99 . In such a container  95 , spillage is capable of being prevented by having the bottom  101  of an upper one of the ingredient assemblies  70 A and  70 B serve to close the top of a lower one of the ingredient assemblies  70 B and  70 C, respectively, during shipping. In this way the filter material otherwise needed for the top  93  is eliminated and the cost of the filter material saved without the problem of spillage during shipment, for the snug relationship between the vacuum container  95  and the stacked assemblies  70 A,  70 B and  70 C holds all of the ingredient assemblies together. Preassembly of the ingredient  70  within the filter envelope substantially reduces the manual labor required in known brewers in which the filter cones are manually filled with the beverage ingredient. 
     Referring now to FIG. 5A, in accordance with the brewing method of the present invention, the brew cycle  84  is divided into three distinct time periods. First, a pre-dispense period, or pre-wetting period,  86  of approximately fifteen seconds occurs during which time the top surface  72  of the ingredient layer  70  is wetted. In the case of ground coffee, this prewetting allows the gasses that are generated from the initial wetting of the coffee to be released so as not to subsequently interfere with the uniform contact of the hot water with the coffee grounds during the subsequent intermittent dispense period that begins at time t 1 . Next, the intermittent dispense period  88  begins at time t 1  and continues until a time selectable between time t 2 ′ and time t 2 , which are preferably four minutes and five minutes after time t 1 , respectively. At time t 2 , or an earlier time between time t 2 ′ and time t 2 , the intermittent dispensing of hot water is terminated and the post-dispense period  90  begins and then continues until time t 3 . During the post-dispense period, or drip period,  90  the last of the hot water that was dispensed into the ingredient holder during the intermittent dispense period  88  is allowed to seep through the layer of ingredient  70  and drain out through the brewed beverage outlet  80  into the brewed beverage container  28 . 
     Referring to FIG. 5B, in accordance with the brewing method of the invention the intermittent dispense period  88  is divided into a plurality of control periods, preferably sixteen to twenty, each of which is preferably fifteen seconds in duration. Thus, when a maximum intermittent dispense period of five minutes occurring between times t 1  and t 2 , there are twenty control periods, CP 1  through CP 20 . When the minimum duration of the dispense period  88  occurring between t 1  and t 2 ′ is selected then there are only sixteen control periods CP 1  through CP 16 . If the intermittent period  88  is selected to end between times t 2 ′ and t 2 , then appropriate ones of the control periods CP 17 , C 18  and C 19  eliminated to achieve dispense period durations of 4.25, 4.5 and 4.75 minutes. 
     Referring now to FIGS. 6A, and  6 B and  6 C, in accordance with the beverage brewing method of the present invention, during a preselected portion each of the control periods that constitute the dispense period  88 , such as control periods CP 1  through CP 20 , only CP 1 , CP 5 , CP 9 , CP 13  and CP 17  being shown, a cortrol signal  92  is generated. A shown in FIG. 6A, in one mode of operation, the percentage of each control period during which the control signal is generated, or duty portion of each control period, such as 50%, remains the same throughout the dispense period. In such case, the dispense flow rate remains the same throughout the dispense period  88 . If it is desired to increase the total flow rate without changing the duration of the dispense period  88  and without changing the uniform flow throughout the dispense period  88 , then the duty portion of all the control periods is increased proportionately by the same amount. For instance, presuming the duty portion is 50%, as shown if FIG. 6A, then to increase the total quantity of hot water dispensed during the dispense period by ten per cent, the duty portion of each of the control periods is increased from 50% to 55%. Likewise, in order to decrease the total amount of hot water dispensed by 20%, for instance, then the duty portion of each of the control periods is decreased from 50% to 40% . 
     Referring to FIG. 6A, the duty portions do not have to be selected to be the same throughout the dispense period  88 . In FIG. 6A, the duty portions of successive control periods has been selected to increase from approximately 20% duty portion of control period CP 1  to approximately 80% for CP 17 . In such case, the flow rate is not uniform over time but increases during the dispense period  88 . 
     Referring to FIG. 6C, the duty portions of successive control period has been selected to decrease from approximately 100% at control period CP 1  to approximately 20% at control period CP 17 . In such case, the flow rate is not uniform over time but decreases over time during the dispense period in order to reduce the duration of the post dispense period. 
     In accordance with the present invention, the duty portion of each of the control periods is individually selectable, and is not limited to any particular flow rate profile. 
     In order to decrease and increase the total time of the dispense period  88  without changing the total amount that is dispensed, the duty portion of all the control periods is selectively, proportionately increased and decreased. For instance, if the dispense period is increased from four minutes to 4.5 minutes, a reduction of 12.5%, then the duty portion of each of the control periods is increased by 12.5%. 
     Preferably, a beverage brewer operating computer program stored in the program memory  48  operates in accordance with the composite logic flow chart of FIGS. 7A and 7B. After the program. starts at step  94 , in step  96  a determination is made as to whether full AC brewer power is on. If so, then in step  98  the microprocessor  42  runs a self-diagnostic sub-routine to determine if the brewer is ready to operate. For instance, a determination is made as to whether there is sufficient hot water in the brewing liquid supply  30  and whether the hot water is at a preselected temperature. If everything is not correct for operation, then in step  100  a determination is made to proceed to step  102  at which an error message is displayed. If everything is ready for operation, then the program moves to step  104  at which ready indicators are actuated and the program advances to step  106 . In step  106  a determination is made as to whether a user program mode has been selected in which the total time duration of the dispense period  88  is selected and the duty portion of each of the control periods of the dispense period is specified. If the user program mode has been selected, in order for the user to program the dispense period, then in step  108  a user program subroutine is entered that is examined below with respect to FIG. 8 Upon completion of user programming, the program proceeds to junction A and continues to FIG.  7 B. Likewise, if the user program mode has not been selected, the program proceeds to junction A and FIG.  7 B. 
     Turning to FIG. 7B, after junction A, the program proceeds to step  110  where a determination is made whether a start brew switch has been actuated. If the start brew switch has been actuated, the program proceeds to step  112  at which step a brew cycle dispenser valve controller sub-routine of FIG. 9 is entered and the dispenser valve is controlled accordingly. After a determination is made in step  114  that the brew cycle has ended, in step  116  the program returns to the start  94  of FIG.  7 A. 
     Turning to FIG. 8, the user program mode subroutine begins at start  118 , and then proceeds to step  120  at which the current contents of a dispenser valve control register in the data memory  50  is displayed to provide a visual indication of the number of control periods that have been selected for the dispenser period  88  and the duty portion of each of the selected control period. in step  122 , a prompt is provided to either enter the dispenser flow profile that is displayed or to change the dispenser flow profile. In step  124 , if the user selects enter, then in step  126  the program returns to junction A of FIG.  7 A. If not, then in step  125  the program waits for the next command. If there is a next command, in step  126  the program prompts the user for selection of the time duration of the dispense period. The user is provided with a prompt to select the one of four dispenser period durations of 4, 4.25, 4.5 and 5.0 minutes. In step  128 , a determination is made as to whether the dispenser period duration has been selected. 
     If a new dispenser period duration has been selected, then in step  129  the duty portions are automatically changed proportionately, indirectly to maintain the selected total quantity of brewing liquid to be dispensed during the entire dispense period. Then in step  130  a prompt is provided to the user to select a dispenser period flow rate profile. This is done by simply selecting one of a plurality of preselected flow rate profiles stored in the data memory  50 . Alternatively, the user creates a new flow rate profile by selecting the duty portion of each of control periods that compose the dispense period  88 . In step  132 , a determination is made as to whether the flow rate profile has been selected. 
     After the profile has been selected, then in step  133  a prompt is provided to select a dispense quantity. If a new total dispense quantity is selected in step  135 , then in step  137 , the duty portions are proportionately directly changed to achieve the new total quantity within the same dispense time period that has been selected. Once the selection is made, the program returns to  120  to display the newly selected flow rate profile and the user is again prompted in step  122  to either enter the new selection or to change the profile. 
     While no time-out steps have been shown, it should be appreciated that in the event action is not taken by the user at any of the decision steps, then after a preselected time out-time period has passed, the program proceeds to the next step, and the setting associated with the decision step remains the same. Also, although not shown, in the absence of the user selecting any of the control parameters, the program reverts to a default setting. 
     Referring to FIG. 9, the brew cycle dispenser valve control program, begins with a start step  138  and then proceeds to step  140  at which the brew cycle is commenced with the opening of the dispense valve for the pre-dispense wetting period  86 . Simultaneously, in step  142 , a brew cycle clock is started. After the pre-wetting period  86  has ended, in step  144 , the dispenser valve control signal is generated in accordance with the dispense flow rate profile that has been selected in accordance with the subroutine of FIG.  8 . After the dispense period has ended, in step  148  the program proceeds in step  146  back to start  138 . 
     While a particular embodiment has been disclosed, it should be appreciated that many variations may be made thereto without departing from the scope of the invention as defined in the appended claims. For instance, while it is preferred to keep the control periods fixed and change the number of control periods to change the total dispense period duration, it is also contemplated to change the total length of the dispense period by keeping the number of control periods the same and changing the length of all of the control periods by the same amount. Likewise, while it is preferred to change the duty portion of each of the control periods by changing the time duration of the on portion during control periods of fixed duration, the duty portion is also changeable by changing the duration of the control period while maintaining a fixed duration of the on time during each control period. Also, while it is preferred that a microprocessor be used to control the dispenser valve, it should be appreciated that the same functions are capable of being implemented in an application specific integrated circuit, discrete circuit, mechanical analogs and the like. While it preferred that the intermittent dispensing be employed with the uniform flow dispenser head, it should be appreciated that the brewing method of the invention that enables controlling flow rate, total amount dispensed and the dispense period duration independently, is capable of being advantageously employed with conventional dispenser heads and ingredient holders. Likewise, the advantages of uniform flow obtained by virtue of the uniform flow dispenser head and the uniform flow ingredient holder remain extant even in the absence of intermittent dispensing, although intermittent dispensing is preferably used in conjunction with the uniform flow dispenser head and ingredient holder.

Technology Classification (CPC): 0