Bread making machine and method with automated dispenser and pause function

Abstract: A bread making machine having an automated dispenser unit and a pause function is described. The automated dispenser unit is integrated within a chamber lid covering a bread making chamber in which bread making ingredients are mixed, kneaded, and baked. The automated dispenser accepts certain ingredients, such as fruit and/or nuts, which are automatically added to the bread making chamber after significant processing of other ingredients in the bread making chamber has occurred. The automatic dispenser unit includes a dispenser door adjacent to the bread making chamber. The dispenser door is held in a closed position by a latch assembly. The latch assembly is mechanically linked to a solenoid core, which moves in response to a control signal issued by electronic control circuitry, causing the dispenser door to open. The bread making machine includes a pause function, which allows a user to temporarily suspend the bread making operation at any time, by pressing a pause key on a user interface keyboard. The bread making operation resumes after a selected time interval has elapsed. The selected time interval may be determined cither by the user or by the electronic control circuitry.

Description: The invention refers to an automatic bread making machine, comprising a bread making chamber for receiving bread making ingredients, a motor for mixing and kneading the ingredients within the chamber, a heater for baking the ingredients within the chamber, electronic control circuitry including a microcomputer for executing a bread making program controlling the operation of the motor and heater, a user interface panel for receiving bread making instructions from a user and for displaying bread making status information to the user, the user interface panel operable to receive a pause instruction, the microcomputer responding to the pause instruction to suspend execution of the bread making program for a time interval determined by the user or the microcomputer and to resume execution of the bread making program after the scheduled time interval has elapsed. A bread making machine of the above-described type is known from US patent 5 435 235. In said prior art machine, actuation of the pause instruction has the effect that the bread making sequence is interrupted always at the same point in time during the bread making sequence, namely at the end of a first bread making process t 1 . After the pause, the duration t 2 of which can be determined by the user by again actuating the pause function or by pre-programming, the bread baking sequence is resumed always at the same point in the sequence, namely at the beginning of a second bread making process t 3 . The purpose of the pause function of US patent 5 435 235 is to enable the user of the machine to take out a dough from the machine during the pause period and to make special arrangements for the dough by correcting the shape of the dough, brushing beaten egg over the surface thereof, or putting therein fillings such as cream and chocolate for buns. Afterwards, the dough is put back into the machine and the bread making process is continued. The pause function known from US 5 435 235 lacks user flexibility. From US 5 615 605 and from EP 241 993 A2 bread baking devices are known in which ingredients can be added to the dough at predetermined points in time of the baking sequence. There is no pause function. The problem underlying the present invention is to improve a bread baking machine of the type described above in such a way that the user has more flexibility in interrupting the bread making sequence in order to be able to add ingredients or influence the process at points in time which can be selected by the user with more freedom than in prior art machines. The solution of this problem by the invention is characterised in that the microcomputer is programmed such that upon actuation of the pause function by the user the operation of the microcomputer is paused in the following program step to suspend the execution of the bread making operation, while storing the current state of the bread making sequence, the current state of the bread making sequence being restored when the execution of the bread making sequence is resumed. According to the invention, actuation of the pause function causes the bread making operation to be suspended as soon as the microprocessor proceeds to the next processing step, i.e. practically immediately. When the bread making operation is suspended, the current state of the operation is saved. When the operation resumes at the end of the pause, the status is restored so that the operation is being resumed at exactly the phase which had been reached when the pause function was actuated. This does not confine the user's ability to interrupt the bread making operation only at a given stage during the bread making process, as in the prior art, but gives the user the possibility to interrupt the process at selectable stages of the process, thus increasing the operational flexibility offered to the user. The invention will hereinafter be explained in more detail with reference to an embodiment shown in the drawings, in which; Figure 1 depicts a bread making machine according to the present invention. Figure 2 is a functional block diagram depicting the electronic control and other circuitry contained within the bread making machine of Fig. 1. Figure 3 is an exploded view of an automated dispenser unit and a chamber lid according to the present invention. Figure 4 is an underside view of the automated dispenser integrated within the chamber lid. Figure 5 is a cross-sectional view of the automated dispenser. Figure 6 is a software flowchart diagram depicting the electronic control circuitry operation of the automated dispenser unit. Figure 7 is a software flowchart diagram depicting the electronic control circuitry operation of a pause function of the bread making machine of Figure 1. Detailed Description of the Invention Figure 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 at 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. Figure 2 is a functional block diagram which depicts the basic electronic circuit components contained within the bread making machine 10 of Figure 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 34A-38A. The microcomputer 32 is powered by a power supply circuit 40, which also powers the motor drive circuit 34A, coil drive circuit 36A, and heat drive circuit 38A. 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 driver circuits 34A-38A. 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 Figure 1) via a keyboard circuit 48, and displays bread making status information on the display unit 18 (see Figure 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 Figure 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 36a under control of the microcomputer 32, together with associated software instruction execution by the microcomputer. Figure 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 dispenser 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 Figures 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. Figure 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 Figure 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 Figure 4, a printed circuit board (PCB) shield 75 supports the microcomputer 32 and other electronic control circuitry (see Figure 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 Figure 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 Figure 5). The dispenser door 62 then swings open and any bread making ingredients contained within the dispenser case 60 are emptied into 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 at 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 Figure 2, and no further user intervention is required. Referring again to Figure 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 18 (see Figure 1), etc. One set of such bread making instructions includes operation of the automated dispenser unit 24, and is depicted in Figure 6. A user may select any of a variety of bread making cycles by using the keyboard 20 (see Figure 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 inquires 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 Figure 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 Figure 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 36A to energize the solenoid coil 36 (see Figures 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 selected time. Prior art bread making machines do not incorporate such a feature, and do not allow temporary interruption of bread making operations 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. Figure 7 depicts a sequence of operations performed by the microcomputer 32 of Figure 2 to provide the pause function. A conditional branch test of whether the user has actuated a pause key of the keyboard 20 (see Figure 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 subroutine 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 120 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 dispenser 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 making chamber 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 progress 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 those operations. It will be appreciated that, although Figures 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 Figure 7 may be provided by performing a first interrupt service request (ISR) routine 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.

Claims: Automatic bread making machine, comprising a bread making chamber for receiving bread making ingredients, a motor for mixing and kneading the ingredients within the chamber; a heater for baking the ingredients within the chamber; electronic control circuitry including a microcomputer for executing a bread making program controlling the operation of the motor and heater; a user interface panel for receiving bread making instructions from a user and for displaying bread making status information to the user, the user interface panel operable to receive a pause instruction, the microcomputer responding to the pause instruction to suspend execution of the bread making program for a time interval determined by the user or the microcomputer and to resume execution of the bread making program after the selected time interval has elapsed, characterised in that the microcomputer is programmed such that upon actuation of the pause function by the user the operation of the microcomputer is paused in the following program step to suspend the execution of the bread making operation, while storing the current state of the bread making program, the current state of the bread making program being restored when the execution of the bread making program is resumed.

Inventors: DREIMANN LEONARD, SIT MICHAEL, WESTFIELD BARBARA A, DREIMANN, LEONARD, SIT, MICHAEL, WESTFIELD, BARBARA A.
Applicants: SALTON
Application year: 1997
Main classification: A21B7
IPC codes: A21B7