Patent Document

CROSS REFERENCE TO RELATED APPLICATION 
     This application claims the benefit of U.S. provisional application Ser. No. 60/284,728 filed Apr. 18, 2001, under 35 U.S.C. 119(e). 
    
    
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     This invention generally relates to electrical hot beverage brewers, such as coffee brewers, and more particularly to such beverage brewers that employ removably mounted brew baskets. 
     2. Discussion of the Prior Art 
     Electrical, commercial, beverage brewers of the type that have a controller that automatically controls a plurality of brewer elements are well known. These brewer elements include a hot water reservoir, a brew valve, or dispense valve, and a fill valve to initially fill the reservoir and to also add water after water is removed through a brew valve to pass over and through ingredient, such as ground coffee beans or ground tea or tea leaves, are well known. These elements are all contained within a housing to which is attached a removable brew basket mounting mechanism to which a brew basket is removably mounted during the brewing cycle. The brew basket has a filter holder for supporting a paper filter within which the ingredient is contained. The brew basket has an open top and inwardly tapers downwardly to a beverage outlet opening. 
     During a brew cycle, the brew valve is opened for a preselected time period corresponding to the desired quantity of beverage to be brewed to pass hot water from the reservoir to a spray head that sprays the hot water through the open top of the brew basket and onto the beverage ingredient. The beverage ingredient is contained within a disposable filter paper that in turn is supported within the brew basket by means of a wire filter holder. The hot water seeps through the ingredient and dissolves portions of the ingredient to make the hot beverage that passes through the filter paper supported by the filter holder, through the brew basket outlet opening and into an urn that is positioned beneath the brew basket outlet opening. 
     After the brew valve is closed at the end of a dispense period of the brew cycle, water remains in the brew basket that has not yet drained entirely through the ingredient. This period of the brew cycle is referred to as the drip period. After conclusion of the drip period, most of all the water that will pass through the ingredient and not be absorbed by the ingredient has passed through the ingredient and the dripping of the beverage out of the brew basket outlet opening substantially stops. The entire brew cycle then ends with the end of the drip period 
     At the end of the brew cycle, the brew basket may be slid out of supportive engagement with the brew basket mounting and away from its operative position beneath the brew valve to remove the depleted ingredient and the filter paper in which it is contained for disposal. A new filter paper is inserted and fresh ingredient added to the new filter paper. 
     It has been known for users of this type of brewer, because of being in a rush to quickly start a new brew cycle, or otherwise due to inattentiveness, to remove the brew basket before the end of the brew cycle. This can result in scalding beverage dripping onto the user or onto a counter or floor as well as hot water being dispensed directly onto and splashing onto the top of the urn and elsewhere. Such circumstance can cause injury due to burns or slipping on spilled water and in the least, alters the intended strength and thus taste of the brewed beverage by reducing the quantity of weaker beverage that passes from the ingredient at the end of the brew cycle. 
     SUMMARY OF THE INVENTION 
     In accordance with the present invention this disadvantage of known brewers is overcome by automatically selectively actuating a locking mechanism that locks the brew basket into the operative position beneath the brew valve at the start of the brew cycle when in the operative position. 
     This objective is achieved by providing in a beverage brewer having a water tank, a brew basket for holding beverage ingredient to be mixed with the water from the water tank, a housing, means for mounting the brew basket for removal from an operative position in which the brew basket safely funnels beverage to a container and an inoperative position removed from the brewer housing and a remote controlled brew valve that selectively passes water from the water tank to the brew basket, and a safety brew basket lock assembly composed of an automatic lock mechanism for selectively locking the brew basket to the housing in the operative position when the brew basket is in the operative position, and a controller responsive to actuation of the start switch to actuate the automatic lock mechanism to prevent removal of the brew basket from the housing during a preselected time period after actuation of the start switch 
     The objective is also obtained by providing in a beverage brewer having a water tank, a brew basket for holding beverage ingredient to be mixed with the water from the water tank, a housing, means for mounting the brew basket for removal from an operative position in which the brew basket funnels beverage to an urn and an inoperative position removed from the brewer housing and a remote controlled brew valve that selectively passes water from the water tank to the brew basket, a safety brew basket lock assembly having a sensor that senses when the brew basket is not in the operative position for making beverage and passing the beverage to a container, an automatic lock mechanism that locks the brew basket to the housing in the operative position when the brew basket is in the operative position and the lock mechanism is actuated, said lock mechanism blocking, if actuated, blocking placing the brew basket in the operative position, and a controller responsive to the sensor to disable the lock mechanism when the brew basket is removed from the operative position to enable placement of the brew basket into the operative position. 
     The objective is obtained also in part by providing in a beverage brewer having a water tank, a brew basket for holding beverage ingredient to be mixed with the water from the water tank, a housing, means for mounting the brew basket for removal from an operative position in which the brew basket safely funnels beverage to a container and an inoperative position removed from the brewer housing and a remote controlled brew valve that selectively passes water from the water tank to the brew basket in response to actuation of a brew start switch, a safety method of brewing by performing the steps of automatically selectively locking the brew basket to the housing in the operative position when the brew basket is in the operative position, and responding to actuation of the start switch to actuate the automatic lock mechanism to prevent removal of the brew basket from the housing during a preselected time period after actuation of the start switch 
     Also, the objective is achieved by providing in a beverage brewer having a water tank, a brew basket for holding beverage ingredient to be mixed with the water from the water tank, means for mounting the brew basket for removal from an operative position in which the brew basket funnels beverage to an urn and an inoperative position removed from the brewer housing and a remote controlled brew valve that selectively passes water from the water tank to the brew basket, a safety method performed by sensing when the brew basket is not in the operative position for making beverage and passing the beverage to a container, selectively locking the brew basket to the housing in the operative position with an automatic lock when the brew basket is in the operative position, controlling the lock mechanism in response to the sensor to disable the lock mechanism when the brew basket is removed from the operative position. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The foregoing advantageous features and objects of the present invention will be described in detail and others will be made apparent in the detailed description of the preferred embodiment of the safety brewer that is given with reference to the several figures of the drawing, in which: 
     FIG. 1 is a functional block diagram of the preferred embodiment of the safety brewer of the present invention; 
     FIG. 2 is a sectional side elevation view of the brew basket sensor assembly that senses when the brew basket has been placed into the operative position beneath the brew valve; 
     FIG. 3A is a sectional side view of an O-ring that is employed with the sensing plunger of the brew basket sensor assembly of FIG. 2; 
     FIG. 3B is a side view, partially in section, of the sensing plunger of the sensor assembly of FIG. 2; 
     FIG. 4 is a transparent, perspective view of the plunger housing of the sensor assembly of FIG. 2 within which is received the sensor plunger of FIG. 3B; 
     FIGS. 5A and 5B are plan and side elevation views of the sensor housing; 
     FIG. 6 is an exploded perspective view of the brew basket automatic lock assembly; 
     FIG. 7 is a perspective view of the automatic lock assembly of FIG. 6 when assembled; 
     FIG. 8 is a sectional side view showing the brew basket engaging the sensor mechanism and locked into the operative position; and 
     FIG. 9 is a flow chart of the portion of the computer program installed in the controller computer of FIG. 1 that controls the brew basket lock mechanism of FIGS. 6 and 7 in response to signals from the brew basket sensor assembly, a start brew switch actuation and the internal timing of the computer to measure the duration of a brew cycle, once initiated by actuation of a start brew switch. 
    
    
     DETAILED DESCRIPTION 
     Referring to FIG. 1, the preferred embodiment of the safety brewer  20  of the present invention is seen to include a number of generally conventional elements in addition to novel elements that enable the achievement of the objects of the invention. The conventional elements are the controller  14  with a microcomputer  16  and an interface  18 . The interface connects the computer  16  with a number of conventional elements: a message display unit  22 , a fill valve  24 , an operator control panel  26 , a temperature sensor  30  that senses the temperature of the hot water in a hot water reservoir  28 , a level sensor  32  that senses the level of the water in the reservoir  28 , a brew valve  34 , a dispense spray head  36  connected to the outlet side of the brew valve  34  and a housing  38  that contains all of the above elements. 
     Attached to an underside of the housing is a basket mount  38  that removeably mounts the removable brew basket  40  in a operative position beneath the dispense spray head  36  and above an urn  42  and an urn support  44 , if any. In some cases there is no urn support  44 , and the brew basket is supported over a counter top or table top  46  by a support for the housing that allows the urn to rest on the underlying surface counter top  48  or the like. 
     These conventional elements form no part of the present invention, and reference may be made to U.S. Pat. No. 5,000,082 issued to Lassota on Mar. 19, 1991 for “Beverage Maker and Method of Making Beverage”; U.S. Pat. No. 5,331,885 issued to Lassota on Jul. 26, 1994 for “Semiautomatic Beverage Maker and Method”; U.S. Pat. No. 5,943,944 issued to Lassota on Aug. 31, 1999, for “Brewing System with Hot Water Urn Flushing Apparatus”; U.S. Pat. No. 5,953,981 issued to Lassota on Sep. 21, 1999; and patents cited therein, hereby incorporated by reference, for further information concerning such standard features. 
     In accordance with the invention, when the brew basket  40  is loaded with ingredient and then moved from the inoperative position, shown in broken line  40 ′, to the operative position, shown in solid line, a brew basket sensor  48  detects the presence of the brew basket  40 . A detection signal is sent from the brew basket sensor  48  to the microcomputer  16  through the interface  18 . In response to this brew basket detection signal, the microcomputer  16 , through the interface  18 , sends a lock signal to a remote controlled brew basket lock  50 . The remote controlled brew basket lock is actuated by the lock signal to lock the brew basket  40  in the operative position, as shown in solid line and as described above. The microcomputer  16  keeps the brew basket locked into position until the end of the brew cycle, including the drip period. 
     Referring to FIG. 2, the brew basket sensor assembly  48  is preferably an electromechanical sensor that includes a plunger  52  that is mounted for sliding movement within a bore  53  in a sensor housing  55 . The top  56  of the brew basket  40  carries a sensor engagement member  58  that engages the plunger  52  when it is moved into operative position. The plunger  52  carries a beveled cam surface  53  that is laterally engaged by a convex surface  57  of the engagement member  58  when the brew basket is laterally slid along parallel, spaced rails of the brew basket mount  38  in the direction of horizontal arrow  61 . This lateral engagement cams the plunger  52  upwardly in the direction of arrow  59  against a resilient downward force provided by a spiral bias spring  60 . The upper end of the plunger  52  carries a switch engagement member  62  that is pushed against a switch actuator  64  of a switch  65  contained in an upper part  55 ′ of the sensor housing  55 . 
     As best seen in FIGS. 3A and 3B, the plunger  52  has an annular groove  66  within which is mounted an O-ring, annular seal  68 . The O-ring seal  68  resiliently presses against the interior cylindrical surface  54  of the bore  53  within which the plunger  52  slides up and down to create a moisture and steam impervious seal. This seal between the plunger  52  and the inside surface  54  of the bore  53  protects the upper part of the housing  55 ′ containing the switch actuator  64 , switch  65  and the controller  14  against moisture and steam coming off of the open top of the brew basket  40  during brewing. 
     The hemispherical switch engagement member  62  is mounted at the upper end of an elongate pin body  63 . The pin body  63  is received through a narrowed passageway  70  that is in open communication with an upper portion of the bore  53  located above the plunger  52 . The body of the elongate pin  63  is adjustably mounted within an internally threaded pinhole  72  of the plunger  52  by means of a mating external screw threads  75  on the distal end of the elongate pin  63 . The diameter of the switch engagement member  62  is larger than that of the body of the elongate pin  63  to form a shoulder  77 . This shoulder is wider than the diameter of the pin hole and engages the horizontal surface surrounding the top of the pinhole  70  to block the downward sliding removal of the pin  62 ′ and the plunger  52  from without the bore  54 . When the sensor engagement member  58  carried by the brew basket  40  is not engaged with the plunger  52 , the bias spring  60  that surrounds the pin  63  resiliently presses the top of the plunger  52  downwardly to the position shown in FIG.  2 . As seen, in this position the shoulder  77  at the bottom of the hemispherical engagement member  62  abuts the bottom of a bore  74  surrounding the opening to the pinhole, or passageway. When the sensor engagement member  58  slid to a position directly beneath the bottom of the plunger  52 , it supports the bottom of the plunger at the level  76 , and the sensor detection member  62  is elevated a like amount and thereby pushed against the switch actuator  64  of the switch  65 . When the brew basket is removed, then the spring  60  returns the plunger  52  from level  76  to the level shown in FIG. 2, and the switch engagement member  62  is moved downwardly to the position shown in FIG. 2 at which it is no longer engagsing the switch actuator  64 . 
     Referring to FIGS. 4,  5 A and  5 B, the upper part  55 ′ of the housing is seen to have a rectilinear slot  67  with an open top that is integrally molded together with the lower part of the housing  55 . The slot extends radially beyond the cylindrical lower housing  55  and protectively contains a box-like switch housing  80  of the switch  65 . As also seen, the lower housing  55  has a pair of radially opposed mounting tabs  82  and  84  with mounting holes located above the highest level that can be reached by the plunger  52 . Referring now to FIGS. 6 and 7, the preferred implementation of the remote controlled brew basket lock  50  is seen to comprise a solenoid coil  84  with a metal locking pin  86  mounted for sliding movement within a central air core about which the coil  84  is wrapped. The locking pin  86  is supported within the core by means of a threaded nut  88  that fastens to the top of the pin  86 . The threaded nut secures a spiral bias spring  90  that is wrapped around the body of the pin  86  outside of the core. A cylindrical grommet  89  is received within the core and, in turn, snugly receives the locking pin  86  within a central, cylindrical passageway. A retainer  91  is mounted into the core that also snugly fits around the pin  86  and which abuts an enlarged portion  86 ′ of the pin  86  at the locking end to prevent removal of the pin  86  upwardly out of the core. The coil spring acts  90  between the nut  88  and a bracket  93  overlying the core to spring bias the pin  86  toward an upward position in which the brew basket  40  is not locked. 
     The two ends of the coil  84  are attached to electrical connectors  92  and  94 . When electrical power is applied to the connectors by the computer  16  to lock the brewer  20 , the pin  86  is caused to move downwardly against the force of the bias spring until it is stopped from further downward movement by the head of nut  88  abutting against the top of the bracket  94 . The pin  86  remains in the downwardly extending locking position in which it blocks sliding removal of the brew basket from basket mount  38  until the coil  86  is de-energized. When the coil is de-energized the bias spring  90  is enabled to return the pin  86  to the elevated non-locking position. Preferably, the pin extends into the interior of the brew basket adjacent the top of the back inner side of the brew basket to prevent removal. Alternatively, when in the locking position, the bottom of the pin  86  extends into a mating hole in the top edge of the brew basket  40  to block sliding removal of the brew basket  40 . 
     Referring now to FIG. 8, it is seen how the brew basket engages the brew basket sensor  48  and the pin  86  locks the brew basket in the operative position by blocking its removal from the basket mount  38 . Preferably, the pin member  86  enters into the open brew basket and thereby blocks the back side against sliding removal from the mount  38  when the sensor  52  is pushed upwardly in the position shown by the back side of the upper edge of the brew basket  40 . 
     Referring now to FIG. 9, a flow chart of the portion of the computer program that is installed in the microcomputer  16  to control the locking and unlocking of the brew basket is shown. After start of the subroutine in step  100 , a determination is made in step  102  as to whether the brew basket  40  is detected as being mounted in the operative position. If the brew basket  40  is not detected, then in step  104 , the brew start switch  27  of the operator control panel  26  is disabled from starting a brew cycle even if actuated. If the brew basket is detected in step  102 , then in step  104 , the brew start switch  27  is enabled to initiate a new brew cycle. Then, in step  106 , a determination is made as to whether a brew start switch  27  has been actuated to start a new brew cycle. If not, then the program returns in step  108  to the start  100  and the program recycles. If a brew start switch  27  has been actuated, then in step  110 , the brew basket  40  is locked in place by the remote controlled brew basket lock  50 . Next, in step  112  a determination is made as to whether the brew cycle, including the drip period, as lapsed. The brew cycle has last a preselected time after actuation of the brew start switch  27 , and the determination of completion of the brew cycle is made by measuring the time until the preselected time period has lapsed. If the brew cycle time has lapsed, the brew basket remains locked. If the brew cycle has ended, then the brew basket is unlocked in step  114 . The program then returns to start  100  of this portion of the control. In addition, as an extra precaution, even if the brew cycle has lapsed, the status of the brew cycle is checked and even the brew cycle period has lapsed, if the brew valve is open for any reason, the brew basket will remain locked. 
     While a detailed disclosure has been made of the preferred manner of implementing the application, it should be appreciated that many variations of the details may be made without departing from the scope of the invention that is set forth in the appended claims. For instance, while the particular form of the locking mechanism and the basket sensor have obvious advantages, other locking mechanisms and detectors of greater or lesser complexity may be employed while still obtaining the safety features of the invention. Reference should therefore be made to the appended claims.

Technology Category: 1