Patent Publication Number: US-6217924-B1

Title: Breadmaking machine and method with automated dispenser and pause function

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
     This application is a Divisional of U.S. patent application Ser. No. 09/304,215, filed May 3, 1999, now U.S. Pat. No. 6,095,034, which is a Divisional of U.S. patent application Ser. No. 08/711,130, filed Sep. 9, 1996, now U.S. Pat. No. 5,947,005. 
    
    
     TECHNICAL BACKGROUND 
     This invention relates generally to electrical appliances used in food preparation, and more particularly, to automatic bread making appliances. 
     BACKGROUND OF THE INVENTION 
     In recent years, automatic bread making machines have become increasingly prominent in the marketplace. These machines make bread without requiring a user to expend the time and effort associated with the mixing, repeated kneading, and baking. Bread making machines allow the user to pour the bread making ingredients into the machine, to press a few selected control buttons, and to leave the machine to do the work. 
     Developments in bread making machine technology have increasingly automated the entire bread making process, thereby requiring less and less user intervention. However, certain types of breads require different sets of ingredients to be combined at different times. Today&#39;s bread making machines provide for this by issuing audible signals indicating to the user that a next set of ingredients must be added to the bread making machine. At best, this is inconvenient. At worst, the bread may be ruined if the user does not add the ingredients at the proper time. 
     A related problem is that once a bread making cycle has begun, currently available bread making machines cannot be stopped without them being restarted at the beginning of the cycle. Therefore, it can be difficult to add previously forgotten ingredients. Also, a user cannot choose to extend the bread dough rising time beyond that of the preprogrammed bread making cycle. 
     It can be appreciated that there is a need for improved automation of bread making machines. It can also be appreciated that there is a need to allow user intervention in the bread making cycle, without then requiring the bread making machine to be restated at the beginning of the cycle. The present invention provides these and other advantages, as will be apparent from the following detailed description and accompanying figures. 
     SUMMARY OF THE INVENTION 
     According to the present invention, a bread making machine having an automated dispenser is provided to significantly improve the convenience of preparing certain times of breads. Ingredients such as fruit and/or nuts, which are typically added only near completion of bread dough kneading, are placed in a dispenser unit separate from a bread making chamber, in which the other bread making ingredients are contained. The automated dispenser includes a dispenser case for holding the fruit and/or nuts and a dispenser door separating the dispenser case from the bread making chamber of the bread machine. The dispenser door is held closed by a door latch, which responds to an electric signal to open the dispenser door, thereby emptying the fruit and/or nuts into the bread making chamber. 
     An automatic bread making machine, according to the present invention, includes a bread making chamber having a top opening for receiving a first set of bread making ingredients. A dispenser unit holds a second set of bread making ingredients and empties these ingredients into the bread making chamber in response to an electric signal produced by electronic control circuitry. A motor is provided for mixing ingredients within the bread making chamber, and a heater is provided for baking the ingredients within the chamber. The electronic control circuitry controls the operation of the motor and the heater. Also provided is a user interface panel including a keyboard and a visual display. The keyboard provides a means for the user to enter certain bread making instructions, and the visual display provides bread making status information to the user. 
     Also in accordance with the present invention, the operation of the bread making machine may be temporarily suspended at any time during the bread making process, by receipt of a pause instruction from the user. One advantage of this feature is that the bread making process can be stopped temporarily to add ingredients or for observation, without having to restart the entire bread making cycle over again. The user interface panel keyboard includes a pause key which is actuated by the user to transmit the pause instruction to the electronic control circuitry. The electronic control circuitry includes a microcomputer which executes a bread making program. The microcomputer responds to the pause instruction by suspending execution of the bread making program for a selected time interval, and resuming execution of the bread making program after the selected time interval has elapsed. The selected time interval be determined either by the user or automatically by the electronic control circuitry. 
    
    
     BRIEF DESCRIPTION OF THE FIGURES 
     FIG. 1 depicts a bread making machine according to the present invention. 
     FIG. 2 is functional block diagram depicting the electronic control and other circuitry contained within the bread making machine of FIG.  1 . 
     FIG. 3 is an exploited view of an automated dispenser unit and a chamber lid according to the present invention. 
     FIG. 4 is an underside view of the automated dispenser integrated within the chamber lid. 
     FIG. 5 is a cross-sectional view of the automated dispenser. 
     FIG. 6 is a software flowchart diagram depicting the electronic control circuitry operation of the automated dispenser unit. 
     FIG. 7 is a software flowchart diagram depicting the electronic control circuitry operation of a pause function of the bread making machine of FIG.  1  . 
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     FIG. 1 shows a bread making machine  10  in accordance with the present invention. The bread making machine  10  includes a chamber lid  12  which covers a bread making chamber in which the various bread making ingredients are mixed and baked. The lid  12  is pivotally mounted on hinge  14  and includes a handle  15  to provide user access to the bread making chamber within the bread making machine  10 . The bread making machine  10  includes a user interface panel, such as control panel  16 . The control panel  16  includes a display unit  18  for displaying bread making selections made by the user, as well as displaying the status of bread making operations. The control panel  16  also includes a keyboard  20  with which the user is able to select certain bread making instructions. The lid  12  also includes a window  22  through which a user can observe the bread making procedure. 
     Integrated within the lid  12  is an automated dispenser unit  24 . The dispenser unit  24  includes a pivotally mounted dispenser lid  26 . An aperture  30  within the lid  12  conveniently allows a user to lift open the dispenser lid  26 , thereby providing access to the interior of dispenser unit  24 , described in detail below. The dispenser unit  24  receives a set of bread making ingredients, such as nuts and/or fruit, which is added to the bread making chamber only after significant processing of other bread making ingredients contained within the bread making chamber. 
     FIG. 2 is a functional block diagram which depicts the basic electronic circuit components contained within the bread making machine  10  of FIG.  1 . Electronic control circuitry includes a microcomputer  32  which controls the functioning of an electric motor  34 , a solenoid coil  36 , and a heat unit  38  via respective electronic drive circuits  34 A- 38 A. The microcomputer  32  is powered by a power supply circuit  40 , which also powers the motor drive circuit  34 A, coil drive circuit  36 A, and heat drive circuit  38 A. The power supply circuit  40  is preferably connected to an external AC electrical source  42 , such as a 120 V, 50-60 Hz source. The power supply  40  provides both DC power to the microcomputer  32  and AC power to the drive circuits  34 A- 38 A. The AC power output of the power supply circuit  40  is monitored by a zero crossing detector  44  coupled with the microcomputer  32 , thereby allowing the microcomputer to adjust the speed of the motor  34  in a well-known manner. 
     The microcomputer  32  includes software instruction processing means, such as a microprocessor, for executing a series of preprogrammed bread making instructions which are stored in a data/instruction storage means, such as a computer register or memory. Before beginning execution of the bread making instructions, the microcomputer  32  is placed in an initialized state by a reset circuit  45  in conventional fashion. The microcomputer  32  receives a clock signal input from a clock circuit  46 , receives user instructions from the keyboard  20  (see FIG. 1) via a keyboard circuit  48 , and displays bread making status information on the display unit  18  (see FIG. 1) via a display circuit  50 . The microcomputer  32  also receives one or more signals from a temperature sample circuit  52  and adjusts the operation of the heat unit  38  accordingly. The microcomputer  32  can communicate status information audibly, such as an end-of-cycle tone, via a buzz circuit  53 . 
     Each of the circuits whose function and interconnection is described in connection with FIG. 2 is of a type known in the art, and one skilled in the art would be able to use such circuits in the described combination to practice the present invention. The internal details of these particular circuits are not part of, nor critical to, the invention. Therefore, a detailed description of the internal circuit operation is not required. Instead, those skilled in the art will appreciate that significant advantages are achieved by, for example, providing the solenoid coil  36  and drive circuitry  36   a  under control of the microcomputer  32 , together with associated software instruction execution by the microcomputer. 
     FIG. 3 is an exploded view drawing showing the dispenser unit  24  positioned between an outer lid portion  54  and an inner lid portion  56  of the chamber lid  12 . The dispenser lid  26  is shown in an open position and reveals an upper opening  58  of a dispenser case  60 . The dispenser  24  also includes a disperser door  62 , shown in the open position. The dispenser door  62  is pivotally mounted to the dispenser case  60  by hinge pins  61  held by retainer clips  67 . The dispenser door  62 , when closed, covers a lower opening  63  in the dispenser case  60 . When the dispenser door is in the closed position, a latch hook  64  engages a door latch assembly  65  (see FIGS,  4  and  5 ), a portion of which protrudes from a latch assembly housing  66  of the dispenser unit  24 . As will be described in detail below, the door latch assembly is actuated by a wedge  68 , which is linked to, and mechanically actuated by, a push rod  69 . 
     FIG. 4 shows an underside view of the dispenser unit  24  integrated within the chamber lid  12 , and also shows an underside view of the control panel  16 . A portion of the inner lid  56  and the latch assembly housing  66  has been omitted to provide a view of the latch assembly  65  and its interaction with the wedge  68 . The latch assembly  65  includes a latch slide  70  and a latch spring  72 . As also seen in the cross-sectional view shown in FIG. 5, the latch spring  72  biases the latch slide  70  into engagement with the latch hook  64  to maintain the dispenser door  62  in a closed position over the lower opening  63  of the dispenser case  60 . The latch slide  70  has a tapered groove  74  which receives the wedge  68 . 
     Referring to FIG. 4, a printed circuit board (PCB) shield  75  supports the microcomputer  32  and other electronic control circuitry (see FIG. 2) within the control panel  16 . Adjacent to the PCB shield  75  is a solenoid  76 , including the solenoid coil  36  and a movable core or plunger  80 . A plunger spring  82  biases the plunger  80  in a direction away from the push rod  69 . Upon electrically energizing the solenoid coil  36 , the plunger  80  is moved in a direction opposite to the bias of the plunger spring  82  and a first-plunger head  84  on the plunger pushingly engages a second plunger head  86  attached to the other end of the push rod  69 . The first and second plunger heads  84 ,  86  are not physically connected, thereby allowing pivotal rotation of the chamber lid  12  relative to the control panel  16  (see FIG.  1 ). Energizing the solenoid coil  36  causes the push rod  69  to move the wedge  68  further within the tapered groove  74  of the latch slide  70 , which in turn causes the latch slide  70  to move in a direction opposite the bias of the latch spring  72 , thereby releasing the latch hook  64  of the dispenser door  62  (see FIG.  5 ). The dispenser door  62  then swings open and any bread making ingredients contained within the dispenser case  60  are emptied in to the bread making chamber. 
     The automated dispenser unit  24  of the bread making machine  10  according to the present invention affords numerous advantages over prior art bread making machines. Previously, any breads containing, for example, fruit and/or nuts required the bread making machine to issue an audible signal indicating to the user the appropriate time it which to add the fruit and/or nuts during a bread dough kneading cycle. Thus, the present invention provides superior automated bread making by allowing the user to insert ingredients, such as fruit and/or nuts, into the automated dispenser unit  24  at any convenient time prior to the appropriate time during the kneading cycle. The ingredients are then automatically added to the contents of the bread making chamber under control of the microcomputer  32  of FIG. 2, and no further user intervention is required. 
     Referring again to FIG. 2, the microcomputer  32  executes a series of preprogrammed bread making instructions and correspondingly controls the operation of units such as the motor  34 , solenoid coil  36 , heat unit  38 , display unit  13  (see FIG.  1 ), etc. One set of such bread making instructions includes operation of the automated dispenser unit  24 , and is depicted in FIG. 6. A user may select any of a variety of bread making cycles by using the keyboard  20  (see FIG.  1 ). The key circuit  48  communicates the selection to the microcomputer  32  where the selection is registered therein in step  90 . In step  92 , the microcomputer  32  then inquiries whether a start key has been actuated by the user. In the preferred embodiment of the present invention, a multifunction key for both start and pause functions is employed. The pause function is described below in connection with FIG.  7 . 
     If the start key is actuated, the bread making operation commences in step  94 . In a conditional branch step  96 , the microcomputer  32  determines whether one of a plurality of bread types has been selected which may require use of the dispenser unit  24 . If not, the selected bread making operation continues with steps  98  and  100  until the end of the bread making operation at step  102 . If a selected bread type may require use of the dispenser unit  24 , the microcomputer  32  proceeds to a conditional branch step  104 , in which it is determined whether the automated function of the dispenser unit  24  has been expressly selected/deselected. In the preferred embodiment of the present invention, selection of a bread type which may require use of the dispenser unit  24  results in a default selection of the dispenser unit function. The user may then deselect the automated function of the dispenser unit  24 , or toggle between selected and deselected states, by actuating a dispenser select key included in the keyboard  20  (see FIG.  1 ). Since the selection/deselection can be made at any time prior to a dispensing time during the kneading cycle, the test of step  104  is repeated until that dispensing time. If the automated function of the dispensing unit  24  has not been selected, the conditional test of step  106  returns to step  104  until the dispensing time has passed. In the event the automated function of the dispenser unit  24  has been selected, a conditional test of step  108  also returns to step  104  since the automated function of the dispenser unit may be deselected at any time prior to the dispensing time. If the automated function of the dispenser unit  24  has been selected, the microcomputer  32 , in step  109 , causes the coil drive circuitry  36 A to energize the solenoid coil  36  (see FIGS.  2  and  4 ), thereby emptying the contents of the dispenser unit  24  into the bread making chamber. The bread making operation then continues with steps  98 - 102  as described above. 
     The bread making machine  10  according to the present invention also incorporates a novel pause function, allowing a user to temporarily suspend the bread making operation at any time, and to resume the bread making operation at a later time. Prior art bread making machines do not incorporate such a feature, and do not allow temporary interruption of bread making operation to, for example, add previously forgotten ingredients. Once bread making operations have begun in prior art bread making machines, they must continue to the end or be started again from the beginning. It will be appreciated that the pause function provided by the present invention affords significant advantages over the prior art. 
     FIG. 7 depicts a sequence of operations performed by the microcomputer  32  of FIG. 2 to provide the pause function. A conditional branch test of whether the user has actuated a pause key of the keyboard  20  (see FIG. 1) is performed in step  110 . If not, the bread making operation is allowed to continue in step  111 . If the user has actuated the pause function, preferably for a minimum time interval such as 0.5 seconds, the operation of the microcomputer  32  is paused in step  112 . The program state of the microprocessor within the microcomputer  32  is saved, for example, by saving the values of instruction pointer and flag registers within the microcomputer. A pause subrouting  114  is then executed by the microcomputer  32 , in which the timing of bread making operations is suspended, the motor  34  and/or heater  38  is stopped, and the display unit  18  conveys the paused state of the bread making machine to the user. A program loop comprising steps  116  and  118  then determines whether a predetermined time delay has occurred or the pause key has again been actuated by the user, respectively. If either of these events occurs, the bread making program state of microcomputer  32  is restored at step  110  and the bread making operation resumes in step  111 . 
     It will be appreciated that although an embodiment of the invention has been described above for purposes of illustration, various modifications may be made without deviating from the spirit and scope of the invention. Those skilled in the art will appreciate that a number of different automated disperser mechanisms could be employed according to the present invention. For example, a dispenser unit with discrete compartments for different sets of ingredients to be added to the bread at different times is well within the contemplation of the present invention. Also, the dispenser unit may have a different mechanical structure from that described above, while still providing the function of the present invention—namely, automatically dispensing certain bread making ingredients into the bread making chamber only after significant processing of other ingredients in the bread making chamber has occurred. For example, a rotating dispenser unit could be employed. Such a unit would include a compartment with an opening facing away from the bread making chamber prior to the dispensing time, and then rotating the compartment into a position where the opening faces toward the bread making chamber at the dispensing time. Indeed, numerous variations are well within the scope of this invention. 
     It will also be appreciated that the automated dispenser of the present invention can be included in any of numerous electrical kitchen appliances which mix together various ingredients at different times. Some examples include pasta makers, ice cream makers, yogurt makers, electronic stand mixers, food processors, bagel makers, and dough makers. 
     Similarly, the pause function of the present invention can be incorporated into any of a wide variety of electrical kitchen appliances, including those examples identified above. As another example, a bread toaster having the pause function would allow a user to check the process of the bread toasting without effecting the total time for which the bread is toasted. Indeed, the pause function may be advantageously employed any time a user wishes to check the status of kitchen appliance operations without interfering with the overall timing and sequence of these operations. 
     It will be appreciated that, although FIGS. 6 and 7 depict a continuous computer program execution, an interrupt driven protocol may be advantageously employed. In particular, the pause function execution depicted in FIG. 7 may be provided by performing a first interrupt service request (ISR) routine open upon receipt of the first actuation of the pause key, and executing a second ISR routine upon receipt of the second actuation of the pause key or expiration of a timer. As with the automated dispenser unit, the pause function according to the present invention may be achieved by numerous variations within the scope of this invention. Accordingly, the invention is not limited except as by the appended claims.