SLOW COOKER APPLIANCE AND METHOD OF OPERATION

A slow cooker appliance and methods of operation are provided. The slow cooker appliance may include a casing, a heating element, a cooking utensil, and a sealed refrigeration system for circulating a refrigerant. The casing may define a utensil chamber. The heating element may be mounted within the casing proximate to the utensil chamber. The cooking utensil may be received within the utensil chamber. The sealed refrigeration system may include an evaporator and a compressor. The evaporator may be in conductive thermal engagement with the cooking utensil. The compressor may be positioned downstream from the evaporator to compress refrigerant from the evaporator.

FIELD OF THE INVENTION

The present subject matter relates generally to cooking appliances, and more particularly to slow cooker appliances.

BACKGROUND OF THE INVENTION

Slow cookers or slow cooking appliances generally include a heating element that is configured to slowing heat the contents (e.g., food items) within a ceramic pot. A lid may be positioned over the pot to trap heat and/or moisture, allowing food items within the ceramic pot to be slowly heated without becoming undesirably dry. Food items being heated within the pot often require little to no attention from a user. As a result, much of the preparation required may be performed well in advance of the time at which a user wishes to eat a given food item.

Although slow cooking appliances may reduce the amount of active time and effort that a user must expend, limitations still exist. For instance, although certain preparations may be done in advance of cooking or heating, most food items cannot be added until immediately before cooking operations begin. If added too soon, some food items, such as those that normally require refrigeration, may otherwise spoil. Moreover, once cooked, many food items will need to be quickly removed from the pot. From the pot, food items may be stored within a separate container and/or within a refrigerator. If left within the appliance or pot, some food items may overheat or spoil. Removal and/or storage of food items may be difficult, messy, and/or cumbersome. Although some pots are removable from the slow cooking appliance, a user's refrigerator may be unable to accommodate the pot. For instance, the pot may be too large, or the refrigerator may be otherwise full.

Accordingly, it would be advantageous to provide a slow cooker appliance that addressed the above concerns. In particular, it would be advantageous to provide a slow cooker appliance that included one or more features enabling food to be refrigerated or otherwise stored within the slow cooking appliance before and/or after cooking operations take place.

BRIEF DESCRIPTION OF THE INVENTION

In one aspect of the present disclosure, a slow cooker appliance is provided. The slow cooker appliance may include a casing, a heating element, a cooking utensil, and a sealed refrigeration system for circulating a refrigerant. The casing may define a utensil chamber. The heating element may be mounted within the casing proximate to the utensil chamber. The cooking utensil may be received within the utensil chamber. The sealed refrigeration system may include an evaporator and a compressor. The evaporator may be in conductive thermal engagement with the cooking utensil. The compressor may be positioned downstream from the evaporator to compress refrigerant from the evaporator.

In another aspect of the present disclosure, a method of operating a slow cooker appliance is provided. The slow cooker appliance may include a casing defining a utensil chamber, a heating element, a cooking utensil received within the utensil chamber, an evaporator in conductive thermal engagement with the cooking utensil, and a compressor positioned downstream from the evaporator. The method may include determining a heating condition for the cooking utensil, and activating the heating element to transmit heat to the utensil chamber in response to the determined heating condition. The method may further include determining a cooling condition for the cooking utensil, and activating the compressor to circulate refrigerant within the sealed refrigeration system in response to the determined cooling condition.

DETAILED DESCRIPTION

Generally, a slow cooker appliance is provided in exemplary embodiments of the present disclosure. The slow cooker appliance may include a casing that houses an electric heating element. The casing may be shaped to receive a cooking utensil, such as a ceramic or aluminum pot. The cooking utensil is generally configured to hold or contain food items to be cooked. An evaporator may be placed beneath the cooking utensil as part of a sealed cooling system. During use, the electric heating element and sealed cooling system may be alternately or alternatively activated to respectively heat and cool food items within the cooking utensil.

Turning now to the figures,FIGS. 1 and 2provide an exemplary embodiment of a slow cooker appliance10. As illustrated, slow cooker appliance10generally includes a casing12that defines a utensil chamber14. A cooking utensil16, such as a pot, may be positioned or received at least partially within casing12, e.g., at utensil chamber14. A heating element18and sealed cooling system20may be provided to selectively heat or cool cooking utensil16. A lid22may also be provided. During use, lid22may be selectively placed on or over cooking utensil16to restrict air and/or heat passage therethrough. As will be understood, certain items, such as food, can be placed into cooking utensil16. When cooking utensil16is disposed within casing12, appliance10may heat and/or cool the provided food items, as will be described below.

As shown, casing12includes one or more unique walls24,26,28. The walls24,26,28may define utensil chamber14. For instance, an inner wall26may define at least a portion of utensil chamber14, e.g., in a vertical direction V defined by casing12. An outer wall24is disposed radially outward from utensil chamber14and inner wall26(i.e., outward in a radial direction R defined by casing12). Inner wall26may be positioned radially between outer wall24and utensil chamber14. One or more of outer wall24or inner wall26may extend, e.g., substantially in the vertical direction V. In some embodiments, inner wall26at least partially defines utensil chamber14between a lower edge30and an upper edge32. An internal base wall28may extend across a bottom portion of utensil chamber14, defining utensil chamber14, e.g., as a lowermost vertical extreme. Bottom wall28may extend in the radial direction R and/or connect lower edge30of the inner wall26. Upper edge32of inner wall26may be positioned opposite of the lower edge30to define an opening34. As shown, opening34generally permits access to utensil chamber14. In certain embodiments, a top rim36extends radially outward from the upper edge32. Optionally, top rim36may join inner wall26to outer wall24. Additionally or alternatively, top rim36may support cooking utensil16, e.g., when cooking utensil16is received within utensil chamber14.

Between outer wall24and inner wall26, casing12may define an element chamber38. In some such embodiments, a heating element18may be mounted therein. For instance, heating element18may be mounted proximate to utensil chamber14to provide heat thereto. In certain embodiments, heating element18is mounted in fixed contact with inner wall26. Optionally, insulation (e.g., foam insulation) may be mounted within element chamber38. Additionally or alternatively, air may insulate the space between heating element18and outer wall24. Upon being mounted, heating element18may be radially spaced between inner wall26and outer wall24. Additionally or alternatively, heating element18may be disposed about utensil chamber14, e.g., such that heating element18substantially surrounds utensil chamber14. In some embodiments, heating element18is shaped as a single ring (either partially or fully surrounding utensil chamber14). In alternative embodiments, heating element18is shaped as a helical coil. However, other suitable shapes may also be provided in additional or alternative embodiments.

In the illustrated embodiments, heating element18is an electric resistive heating element18. Although a single coiled resistive heating element18is shown, multiple discrete heating elements18may be provided in alternative embodiments. As discussed in greater detail below, each heating element18may be operably connected (e.g., electrically coupled) to a user interface40and/or controller42configured to control one or more elements of appliance10.

In some embodiments, casing12defines an enclosed chamber43that houses all or some of sealed cooling system20. For instance, enclosed chamber43may be defined below internal base wall28. One or more vent apertures44may be defined through casing12, e.g., in fluid communication with enclosed chamber43, to permit air exchange between the ambient environment and enclosed chamber43.

As noted above, cooking utensil16may be received within utensil chamber14. Cooking utensil16generally defines a food cavity46to hold food within appliance10, e.g., during heating or cooling operations. Cooking utensil16may be formed from one or more suitable heat-resistant materials, such as aluminum, glass, ceramic, laminates, plastics, another metal, etc. In some embodiments, cooking utensil16is permanently mounted to casing12. In alternative embodiments, cooking utensil16removably rests on a portion of casing12. For instance, a radial band48of cooking utensil16may rest upon top rim36. In turn, cooking utensil16may be selectively removed, e.g., by lifting radial band48off of top rim36and drawing the remaining portion of cooking utensil16away from utensil chamber14.

A sealed cooling system20is provided to circulate a refrigerant fluid therein. As illustrated, exemplary embodiments of sealed cooling system20include a compressor50, a condenser52, a throttling device54, and an evaporator56. Evaporator56is generally provided in conductive thermal engagement with cooking utensil16(e.g., at a bottom portion of cooking utensil16). Compressor50is generally positioned downstream evaporator56to compress refrigerant from evaporator56.

As is generally understood, various conduits may be utilized to flow or direct refrigerant between the various components of the sealed system20. The compressor50, condenser52, throttling device54, and evaporator56may each be placed in fluid communication such that refrigerant generally flows downstream from the compressor50to the rest of the system before returning to the compressor50.

During operation, the compressor50motivates the refrigerant through the sealed cooling system20and acts to compress the refrigerant through the compressor50, increasing pressure and temperature of the refrigerant such that the refrigerant becomes a superheated vapor. As a superheated vapor, the refrigerant then passes to the condenser52, which may be positioned directly downstream from the compressor50. Within the condenser52, the refrigerant is cooled as heat is drawn therefrom. The refrigerant subsequently exits the condenser52as a saturated liquid and/or high quality liquid vapor mixture. Optionally, a fan58may be provided adjacent to the compressor50, in fluid isolation from the refrigerant. During operation, fan58may force and/or direct air (e.g., through vent apertures44) across condenser52and accelerate heat transfer between condenser52and the ambient environment.

From the condenser52, the saturated liquid and/or high quality liquid vapor mixture travels through the throttling device54, which is configured for regulating a flow rate of refrigerant therethrough. The throttling device54may generally expand the refrigerant, lowering the refrigerant's pressure and temperature. As a result, a cooled form of the refrigerant passes to the evaporator56. While passing through the evaporator56, the cooled refrigerant absorbs heat transferred to evaporator56from cooking utensil16and/or any items therein. Refrigerant may exit the evaporator56in a gasified vapor form before passing back to the compressor50. Additional elements, such as an accumulator (not pictured) may be provided in some embodiments and may be configured to maintain gasification of the fluid flow as the refrigerant passes from the evaporator56to the compressor50. Upon the refrigerant reaching the compressor50, the cycle repeats.

A user interface40and/or controller42are included in exemplary appliance embodiments. User interface40generally includes one or more interface elements, such as a button, switch, touch screen, or display to receive user inputs and/or provide information regarding the slow cooker appliance10. In optional embodiments, user interface40is mounted to casing12, e.g., at outer wall24. Controller42may be operably connected to user interface40and configured to control or regulate the heating element18and/or sealed cooling system20.

Controller42may include memory and one or more processing devices such as microprocessors, CPUs or the like, such as general or special purpose microprocessors operable to execute programming instructions or micro-control code associated with operation of the slow cooker appliance10. The memory can represent random access memory such as DRAM, or read only memory such as ROM or FLASH. The processor executes programming instructions stored in the memory. The memory can be a separate component from the processor or can be included onboard within the processor. Alternatively, controller42may be constructed without using a microprocessor, e.g., using a combination of discrete analog and/or digital logic circuitry (such as switches, amplifiers, integrators, comparators, flip-flops, AND gates, and the like) to perform control functionality instead of relying upon software.

In some embodiments, controller42is operably connected (e.g., electrically coupled) to heating element18and a portion of sealed cooling system20, such as the compressor50. Controller42is configured to selectively and/or separately activate heating element18and compressor50according to one or more input signals.

In certain embodiments, controller42is configured to determine a heating condition for cooking utensil16. Heating condition may generally correspond to a demand for heat to be generated at heating element18. In turn, controller42may activate heating element18in response to the determined heating condition. In optional embodiments, determination of a heating condition includes receiving a user-selected heating signal from user interface40. In additional or alternative embodiments, determination of a heating condition includes determining that a set timing condition has been met, e.g., according to a provided cook cycle. The timing condition for heating element18may be predetermined or prescribed according to a selected user input. For instance, the timing condition for heating element18may be a selected clock time or an elapsed time period. Heating element18may activate at the selected clock time or at the end of the elapsed time period. In still further additional or alternative embodiments, determination of a heating condition includes detecting a temperature threshold (e.g., temperature set point or range).

Upon being activated, heating element18may continue to operate. Operation may be subsequently ceased as dictated by controller42. For instance, controller42may determine a stop time has elapsed. The stop time of the heating element18may be a selected clock time or an elapsed time period. Heating element18may deactivate or cease to operate at the selected clock time or at the end of the elapsed time period. Additionally or alternatively, operation of heating element18may be ceased in response to controller42detecting a temperature threshold (e.g., temperature set point or range). Optionally, operation of heating element18may be ceased in response to determination of a cooling condition.

In some embodiments, controller42is configured to determine a cooling condition for cooking utensil16. Cooling condition may generally correspond to a demand to draw heat away from cooking utensil16, e.g., via evaporator56. Controller42may activate compressor50in response to the determined cooling condition. In optional embodiments, determination of a cooling condition includes receiving a user-selected refrigeration signal from user interface40. In additional or alternative embodiments, determination of a cooling condition includes determining that a set timing condition has been met, e.g., according to a provided cook cycle. The timing condition for compressor50may be predetermined or prescribed according to a selected user input. For instance, the timing condition for compressor50may be a selected clock time or an elapsed time period. Compressor50may activate at the selected clock time or at the end of the elapsed time period. In still further additional or alternative embodiments, determination of a cooling condition includes detecting a temperature threshold (e.g., temperature set point or range). For instance, compressor50may be activated periodically based on a set temperature threshold.

Upon being activated, compressor50may continue to operate. Operation may be subsequently ceased as dictated by controller42. For instance, controller42may determine a stop time has elapsed. The stop time of the compressor50may be a selected clock time or an elapsed time period. Compressor50may deactivate or cease to circulate refrigerant at the selected clock time or at the end of the elapsed time period. Additionally or alternatively, operation of compressor50may be ceased in response to controller42detecting a temperature threshold (e.g., temperature set point or range). Optionally, operation of compressor50may be ceased in response to determination of a heating condition.

Activation of compressor50may optionally occur before activation of heating element18. Additionally or alternatively, activation of compressor50may occur after activation of heating element18. In some embodiments, multiple unique cooking cycles are provided (e.g., within controller42) to activate heating element18and compressor50separately according to discrete patterns or cycles of operation. For instance, certain cooking cycles include activating compressor50to chill food items within the cooking utensil16. After a selected cooling time, compressor50is deactivated and heating element18is activated to heat the food items. Advantageously, food items may be placed within cooking utensil16far in advance of when the food needs to be cooked, while still being held in a reduced preservation temperature. In additional or alternative cooking cycles, activating heating element18is included to heat and cook food items within cooking utensil16. After food is adequately cooked (e.g., after a selected cooking time), heating element18is deactivated and compressor50is activated to chill the food items. Advantageously, cooked food items may be stored for extended periods of time within cooking utensil16, while still being held in a reduced preservation temperature.

Turning now toFIGS. 3 and 4, an exemplary evaporator56embodiment is illustrated. As shown, evaporator56includes a conduit segment60to direct refrigerant therethrough. In some embodiments, a rigid conductive plate70is provided. When assembled, rigid conductive plate70may be in thermal contact with at least a portion of conduit segment60. Optionally conduit segment60may be fixed to conductive plate70. For example, conduit segment60may extend through rigid conductive plate70between a top surface72of rigid conductive plate70and a bottom surface74of rigid conductive plate70. At least a portion of conduit segment60may be defined within rigid conductive plate70. Additionally or alternatively, conduit segment60may include an arcuate and/or serpentine shape. Several passes of conduit segment60may be disposed within rigid conductive plate70and provide a distributed contact surface with rigid conductive plate70.

As illustrated inFIG. 2, evaporator56, which optionally includes rigid conductive plate70, may be positioned away from heating element18. When cooking utensil16is disposed within utensil chamber14, evaporator56may be positioned between internal base wall28and cooking utensil16. Top surface72may face cooking utensil16(e.g., such that bottom surface74is in contact with the bottom portion of cooking utensil16). Bottom surface74may face away from cooking utensil16, e.g., toward internal base wall28. One or more conduit apertures62may be defined through base wall28to permit the passage of conduit to/from additional components of sealed cooling system20, e.g., compressor50within enclosed cavity. Advantageously, separation between heating element18and evaporator56may prevent damage to rigid conductive plate70and allow for lower heat tolerances in the sealed cooling system20.

Returning toFIGS. 3 and 4, conduit segment60and rigid conductive plate70may be formed from one or more suitable conductive materials. The materials of conduit segment60and rigid conductive plate70may be the same, or they may be discrete materials. For instance, conduit segment60may be formed from a first conductive material (e.g., copper, steel, or an alloy thereof) while rigid conductive plate70is formed from another conductive material (e.g., aluminum or an alloy thereof). In certain embodiments, rigid conductive plate70is formed from a suitable conductive material being poured in molten form over conduit segment60. Additionally or alternatively, rigid conductive plate70may be die cast with conduit segment60.

In some embodiments, a compressive substrate76at least partially supports evaporator56(see alsoFIG. 2). For instance, compressive substrate76may be disposed on internal base wall28, below rigid conductive plate70. Compressive substrate76may be positioned between internal base wall28and rigid conductive plate70. In some such embodiments, bottom surface74of rigid conductive plate70is disposed on top of compressive substrate76(e.g., in contact within compressive substrate76), while internal base wall28supports compressive substrate76below. When cooking utensil16is disposed within utensil chamber14, compressive substrate76may bias rigid conductive plate70toward the bottom portion of cooking utensil16, advantageously ensuring thermal contact between evaporator56and cooking utensil16. Compressive substrate76may include one or more suitable elastic structures, such as a foam rubber panel or compression spring, to resiliently deform and/or bias evaporator56toward cooking utensil16.

Turning now toFIGS. 5 and 6, another exemplary evaporator56is illustrated. As shown, evaporator56includes a conduit segment60to direct refrigerant therethrough. In some embodiments, a resilient bladder80is provided. At least a portion of the conduit segment60may extend within the resilient bladder80. For example, conduit segment60may extend within resilient bladder80between a top bladder surface82and a bottom bladder surface84.

In some embodiments, a flowable conductive material86may is disposed within resilient bladder80. The conductive material86may include one or more suitable liquid, fluid, or particulate (e.g., water, propylene glycol, or particulate aluminum). When assembled, the flowable conductive material86may surround at least a portion of the conduit segment60in fluid isolation from the refrigerant. For instance, in some embodiments the flowable conductive material86contacts conduit segment60in conductive thermal engagement. Refrigerant may flow through conduit segment60without contacting or intermingling with flowable conductive material86. Conduit segment60may include an arcuate and/or serpentine shape. Several passes of conduit segment60may be disposed within resilient bladder80and provide a distributed contact surface with flowable conductive material86.

In some embodiments, evaporator56, including resilient bladder80, may be positioned away from heating element18(seeFIG. 2). When cooking utensil16is disposed within utensil chamber14, evaporator56may be positioned between internal base wall28and cooking utensil16. Top bladder surface82may face cooking utensil16(e.g., such that bottom surface74is in contact with the bottom portion of cooking utensil16). Bottom bladder surface84may face away from cooking utensil16, e.g., toward internal base wall28. One or more conduit apertures62(seeFIG. 2) may be defined through base wall28to permit the passage of conduit to/from additional components of sealed cooling system20, e.g., compressor50within enclosed cavity. Advantageously, separation between heating element18and evaporator56may prevent damage to resilient bladder80and allow for lower heat tolerances in the sealed cooling system20.

Resilient bladder80may be formed from one or more suitable flexible materials, such as silicone rubber. Conduit segment60may be formed from one or more suitable conductive materials (e.g., aluminum, copper, steel, or an alloy thereof).

Turning now toFIG. 7, a method200for operating a slow cooker appliance according to an exemplary embodiment of the present disclosure is illustrated. Method200may be used to operate any suitable slow cooker appliance. As an example, method200may be used to operate slow cooker appliance10(seeFIG. 1). Controller42(seeFIG. 1) may be programmed to implement method200.

At210, method200includes determining a heating condition for a cooking utensil. As discussed above, the heating condition may correspond to a demand for heat to be generated and/or provided to cooking utensil. The heating condition may indicate a specific temperature, relative temperature, or a general demand for heat. Determination210may be made, for instance, in response to a user input signal. The user input may be made according to an immediate or a delayed desired for heat (e.g., according to a predetermined program). In additional or alternative embodiments,210includes determining that a set timing condition has been met, e.g., according to a provided cook cycle.

At220, method200includes activating the heating element to transmit heat to the utensil chamber in response to the determined heating condition at210. The heating element may be activated continuously, or according to a predetermined pattern (e.g., a periodic pattern). After the heating element has been activated, the method200may provide for deactivating the heating element, as described above.

At230, method200includes determining a cooling condition for the cooking utensil. The cooling condition may indicate a specific temperature, relative temperature, or a general demand for heat. Determination230may be made, for instance, in response to a user input signal. The user input may be made according to an immediate or a delayed desired for a reduction in heat (e.g., according to a predetermined program). In additional or alternative embodiments,230condition includes determining that a set timing condition has been met, e.g., according to a provided cook cycle.

At240, method200includes activating the compressor to circulate refrigerant within the sealed refrigeration system in response to the determined cooling condition at230. The compressor may be activated continuously, are according to a predetermined pattern (e.g., a periodic pattern). After the compressor has been activated, the method200may provide for deactivating the compressor, as described above.

It is understood that240may occur before or after220, depending on the desired heating or cooling demands, e.g., according to a provided cook cycle. Moreover, one or more of the method steps210,220,230,240may be repeated or reordered without departing from the envisioned method200. For example, multiple instances of step240may be optionally provided, including one instance of step240before step220, and another instance of step240after step240(e.g., according to a predetermined program).