Patent Application
20130175254
The subject matter of the present disclosure relates to a cook top appliance that can determine whether a spill or boil-over event has occurred and, if so, undertakes one or more remedial responses.
Cook top appliances typically can include a variety of configurations for the heating sources located on the cook top surface. The number of heating sources or positions available for heating on the cook top can include e.g., four, six, or more depending upon the intended application and preferences of the buyer. These heating sources can vary in size and location along the surface of the cook top. Further, the types of heating sources available include, for example, gas burner, electric resistance (e.g., hot coil), electric radiant, and induction. For cook top appliances having a glass or ceramic surface for receipt of the cooking utensils, the heating sources can include e.g., include radiant, induction, and gas on glass. A variety of controls can be provided for such heating sources such as e.g., traditional rotatable knobs and/or electronic types that rely on sensitivity to a user's touch.
Cook tops have traditionally relied upon an operator/user to monitor cooking activity and temperatures during use. Attention to whether food is boiling, simmering, or otherwise at a certain temperature and/or for a certain period of time can be important for determining whether proper cooking has occurred. However, during the cooking process where a pot or other utensil is being heated by the cook top, a user of the cook top appliance may become distracted or otherwise pre-occupied and forgo timely monitoring of the food and/or liquid in the utensil. As a result, depending upon the amount of food and/or liquid present within the vessel, a boil-over may occur whereby the side of the utensil and/or and the cook top surface becomes soiled by the liquid food item. As used herein, “boil-over” refers to a condition where food, liquids, or both escape from a cooking utensil (such as e.g., a pot, pan, etc.) because of the application of too much heat—thereby causing the food and/or liquid to boil over, pop, bubble, splatter, or otherwise leave the utensil and travel onto the surface of a cook top. As used herein, “spill” refers to a condition where foods, liquids, or both are accidently deposited onto the cook top surface because of movement of cooking utensils or other cooking paraphernalia by the user. For example, while pouring a liquid ingredient into the cooking vessel, some of the liquid might splash out of the cooking utensil or the user might have misaligned the pouring device and the cooking vessel and directly deposited the liquid onto the cook top surface. As used herein, “food deposit” will refer to the placement of food (liquid and/or solid) onto the cook top surface from a spill, boil-over, or both. When an unwanted food deposit occurs on the cook top surface, if left untreated, it can cause damage to the cooking surface—particularly in the case of the electric radiant type wherein the surface is extremely hot underneath and in the immediate vicinity of the cooking utensil.
For a cook top appliance having a glass or ceramic surface, such events are particularly undesirable. Depending upon the amount of the contamination and the temperature of the surface, cleaning can be very difficult. For example, if the contamination is allowed to remain long enough under sufficient heat, the contaminant could eventually char onto the glass surface and will be extremely difficult to remove afterwards. While the user may be able to remove some of the char residue from the glass surface, permanent damage can occur, particularly in the case of sugar-based substances which can permanently etch the glass surface. The glass surface may remain stained or otherwise damaged even after thorough cleaning.
Accordingly, a cook top appliance that can determine whether a spill or boil-over has occurred onto the surface of the cook top would be useful. Such an appliance that can also undertake one or more remedial actions in response to the detection of a spill or boil-over would be particularly beneficial. The ability to provide such monitoring and response for cook tops with radiant, induction, or gas-on-glass heating sources would also be useful.
Aspects and advantages of the invention will be set forth in part in the following description, or may be obvious from the description, or may be learned through practice of the invention.
In one exemplary embodiment, the present invention provides a cook top appliance having a cooking surface. The appliance includes a heating source for applying a heat input to a cooking utensil placed upon the cooking surface. A sensor zone surrounds the heating source. The sensor zone includes at least one sensor for detecting a food deposit from the cooking utensil. A controller is in communication with the sensor zone. The controller is configured for detecting a signal from the sensor zone that is indicative of the food deposit from the utensil and altering the heat input provided by the heating source once a signal indicative of the food deposit is detected.
In still another exemplary aspect of the present invention, a method for operating a cook top appliance having a heating source surrounded by a sensor zone is provided. The sensor zone includes at least one sensor. The method includes the steps of providing heat to a substance in a utensil placed on the heating source; monitoring the sensor zone to detect a spill-over condition and, if a spill-over is detected, then adjusting the heating source so as reduce or terminate the heating of the substance in the utensil; and, optionally, providing a notification to a user of the appliance.
These and other features, aspects and advantages of the present invention will become better understood with reference to the following description and appended claims. The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and, together with the description, serve to explain the principles of the invention.
A full and enabling disclosure of the present invention, including the best mode thereof, directed to one of ordinary skill in the art, is set forth in the specification, which makes reference to the appended figures, in which:
Exemplary configurations for the positioning of sensors on the cook top appliance are illustrated in the cross-sectional views of
Exemplary configurations for the positioning of detection sensors within or below the material forming the cook top surface are illustrated in the cross-sectional views of
The present invention relates to a cook top appliance that can detect a food deposit from a boil-over or spill by which the food is deposited onto a cook top surface. A sensor zone that surrounds a heating source of the cook top is used to detect the food deposit. Based on the detection of the food deposit, the cook top appliance can take remedial action to e.g., notify the user and/or modify the operation of the heating source. A variety of configurations of the sensor zone are described.
Reference now will be made in detail to embodiments of the invention, one or more examples of which are illustrated in the drawings. Each example is provided by way of explanation of the invention, not limitation of the invention. In fact, it will be apparent to those skilled in the art that various modifications and variations can be made in the present invention without departing from the scope or spirit of the invention. For instance, features illustrated or described as part of one embodiment can be used with another embodiment to yield a still further embodiment. Thus, it is intended that the present invention covers such modifications and variations as come within the scope of the appended claims and their equivalents.
Heating sources 106, 108, and 110 can have a variety of constructions for the input of energy in the form of heat to the cooking utensils. For example, heating sources 106, 108, and 110 can be constructed as electric radiant, electric induction, or gas-on-glass heating sources. Mechanisms associated with each such type of heating source are positioned under cooking surface 104 and will be well understood of one of skill in the art using the teachings disclosed herein.
A user interface panel 112 is located within convenient reach of a user of the appliance 100. For this exemplary embodiment, panel 112 includes touch-type controls 114 that are each associated with one of heating sources 106, 108, and 110. Controls 114 allow the user to activate each heating source and determine the amount of heat input provided by each such element 106, 108, and 110 to a cooking utensil location thereon. Panel 112 may also be provided with one or more graphical display devices that deliver certain information to the user such as e.g., whether a particular heating source is activated and/or the level at which the element is set.
Operation of cooking appliance 100 can be regulated by a controller (not shown) that is operatively coupled i.e., in communication with, user interface panel 112 and heating sources 106, 108, and 110. For example, in response to user manipulation of the control 114 of user interface panel 112, the controller operates one of heating source 110 . The controller is also provided with other features as will be further described herein. By way of example, the controller may include a 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 appliance 100. The memory may represent random access memory such as DRAM, or read only memory such as ROM or FLASH. In one embodiment, the processor executes programming instructions stored in memory. The memory may be a separate component from the processor or may be included onboard within the processor.
The controller may be positioned in a variety of locations throughout appliance 100. In the illustrated embodiment, the controller may be located under or next to the user interface panel 112. In such an embodiment, input/output (“I/O”) signals are routed between the controller and various operational components of appliance 100 such heating sources 106, 108, and 110, controls 114, sensors, graphical displays, and/or one or more alarms as will be further described. In one embodiment, the user interface panel 112 may represent a general purpose I/O (“GPIO”) device or functional block.
Although shown with touch type controls 114, it should be understood that controls 114 and the configuration of appliance 100 shown in
Cooking surface 104 provides an appearance with aesthetics that attract certain consumers. During use, it is desirable to keep cooking surface 104 clean. As described above, however, if a food deposit from a spill or boil-over occurs during use, cooking surface 104 can become soiled. Depending upon e.g., the identity of the substance that spills over, the temperature of the heating source, and the time the substance is allowed to remain in place with the application of heat, the appearance of cooking surface 104 could be permanently stained or damaged.
Accordingly, heating sources 106, 108, and 110 can each be equipped with a sensor zone for detecting a spill-over from a utensil. Based on the detection of the food deposit, appliance 100 can take certain remedial actions. For example, using a controller that is in communication with the sensor zone, once a food deposit is detected, the controller can be configured for remedial action such as providing an audible and/or visual alert to the user of the appliance. This alert could be built-into the appliance, such as a buzzer and/or flashing light, or could be issued to a remote device, such as a text message to the user's cellular telephone or an e-mail to the user's home computer. Alternatively, or in addition thereto, the remedial action could include terminating the operation of the heating source where the spill-over occurred or reducing the heat input from such heating source.
For the exemplary embodiments of
However, if a food deposit occurs during use of cook top 100, the presence of liquid material on cooking surface 104 at a location above one of sensors 118 will change the reflection of the infrared light. For example, some of the infrared light may be absorbed by, or deflected into, the spill-over. As a result, the amount of infrared light detected by the detector of sensor 118 will change. Each sensor 118 is in communication with the controller. This change in the amount of infrared light detected provides a signal to the controller that is indicative of a food deposit from a utensil placed on heating source 109. Upon detecting this signal, the controller can initiate remedial action such as reducing or terminating the heat input from heating source 109, and/or providing an alarm to the user, which could be a visible indication, audible indication, or a combination thereof.
Other configurations of the rings may be used as well. In each case, the rings are positioned around the heating source 109 and preferably not directly over a heating source. Additionally, the rings are preferably located in a manner that places all, or at least a portion, of the rings just outside the diameter or foot print of a cooking utensil placed on heating source 109. In this way, when a food deposit occurs, food and/or liquid of the food deposit will be placed directly over and/or in contact with the rings so as to provide a signal that can be detected by the controller.
By way of example, the concentric rings in each of the sensor zones 120, 122, and 124, can be employed as capacitance-based, or resistance-based, sensors. One of leads e.g., lead 130 acts as one node (electrode) while the other lead 131 acts as the other node (electrode). An electrical signal is placed on e.g., one lead 130 while the other lead 131 acts as a ground. When a food and/or liquid from a spill-over covers at least two of the rings of a sensor zone 120, 122, or 124, the signal is diverted to ground which will, e.g., create a voltage change that can be detected by the controller as indicative of the spill-over. In the case of resistance (impedance, conductance) detection, there is direct flow of electricity from one electrode to the other, for instance, from lead 130, through the liquid, into lead 131. As such, an AC or DC signal may be used. This operation is similar to water detectors one might purchase at a home improvement store for monitoring the area under a sink or behind a refrigerator or washing machine for water leaks. In the case of capacitance detection, an AC (or pulsed DC) signal is used, The AC signal (or edges of a pulsed DC signal) is capacitively coupled from the first electrode to the liquid to be detected, and then capacitively coupled from the liquid to the second electrode. Detection schemes based on a resonance shift caused by a spill-over covering at least two rings can also be used. For detection schemes based as described on capacitance or resonance, the electrically-conductive rings can be placed on the top 100 or bottom 105 of the non-metallic material 102 and if located on the top surface the electrodes would normally be encased within material 102, or otherwise protected from direct contact with the cooking utensils by means of a high-temperature, scratch-resistant, non-electrically-conductive coating. For detection schemes based as described on resistance (conductivity), the electrically-conductive rings would be placed on the top 100 surface of the non-metallic material 102, and left exposed so as to be able to come in electrical communication with the fluid to be detected.
Other sensing schemes using a sensor zone that surrounds heating source 109 may be used well. For example,
A variety of techniques may be used to provide non-metallic material 102 with the electrically conductive, concentric rings described above. By way of example, rings could be applied by silk screening of the metal (in the form of a metallic ink) onto the cooking surface 104 and then heat-treating the surface so as to bond the metallic ink onto surface 104. Alternatively, the rings could be applied as a metal foil that is bonded to surface 104. Depending upon the sensing scheme, the concentric ring can rest completely on surface 104 or could be partially embedded within material 102 such that a portion of the ring remains exposed on top cooking surface 104.
In order to protect the concentric rings from damage during use, the present invention provides several protective configurations that may be used with the rings. For example, as shown in
In still other embodiments, the concentric rings could be completely encased within the non-metallic material forming cooking surface 104. Accordingly,
Still other configurations for applying conductive rings to the non-metallic material of the cook top appliance 100 may also be used. Also, the concentric rings shown in e.g.,
Accordingly, as set forth above, the present invention provides a variety of configurations of the sensor zone. As stated, a controller is placed in communication with the sensor zone. When a food deposit occurs onto the sensor zone, a signal is created that can be detected by the controller to indicate the present of the spill-over. The controller can then undertake one or more remedial actions. For example, the controller can terminate the operation of the heating source or reduce the amount of heat provided by the heating source. As an alternative, or additionally, the controller can also signal the user that a spill-over has occurred using a visual and/or audible alarm. The user can then take additional actions such as e.g., removing the utensil and/or cleaning the food deposit so as to prevent or minimize damage to the cooking surface 104.
Thus, this written description uses examples to disclose the invention, including the best mode, and also to enable any person skilled in the art to practice the invention, including making and using any devices or systems and performing any incorporated methods. The patentable scope of the invention is defined by the claims, and may include other examples that occur to those skilled in the art. Such other examples are intended to be within the scope of the claims if they include structural elements that do not differ from the literal language of the claims, or if they include equivalent structural elements with insubstantial differences from the literal languages of the claims.
