Abstract:
A digital frying pan provides temperature and/or food doneness information associated with food cooked within the pan. A thermal sensor coupled with the pan senses temperature and generates corresponding signals, and processing electronics coupled with the sensor convert the signals to data for display on a LCD. A warning buzzer or LED warns the user of completed cooking. The frying pan may be programmed to desired food types or personal temperatures or food doneness options. The invention also provides a remote sensing food doneness system for remotely viewing and then determining food temperature and/or food doneness. The remote system uses thermal imaging optics and thermal sensing techniques to remotely sense food temperature. Preferably a second optical element images the food onto a CCD to display an image of the food to a user. The system is mounted by a user who views the CCD to ensure appropriate placement in line of sight from the food. A warning is generated by the system to indicate food doneness or desired temperature.

Description:
RELATED APPLICATIONS  
       [0001]    This application claims priority to U.S. Provisional Application No. 60/197,756, filed Apr. 19, 2000; to U.S. Provisional Application No. 60/203,293, filed May 11, 2000; to U.S. Provisional Application No. 60/212,169, filed Jun. 16, 2000; and to U.S. Provisional No. 60/260,038, filed Jan. 5, 2001, each of which is expressly incorporated herein by reference. 
     
    
     
       BACKGROUND  
         [0002]    Cooking over stove and fire has been an age-old occurrence. Assistance in cooking is desirable, such as to assure food temperature and doneness. Cooking pans are used in cooking—but provide no assistance in monitoring food temperature or doneness. One object of the invention is to provide an electronic frying pan to overcome the deficiencies of the prior art. Other objects will be apparent in the description that follows.  
         SUMMARY OF THE INVENTION  
         [0003]    In one aspect, the invention provides an electronic frying pan with a thermally conductive pan for cooking food and a handle connected to the thermally conductive pan. The thermally conductive pan has one or more sensors attached therewith (e.g., inside or outside) to generate signals indicative of one or more characteristics (e.g., temperature) of the pan or food within the pan; the handle has electronics connected to the sensors for providing indications to a user of the frying pan regarding food cooked within the pan. Preferably, the handle electronics may be removed from the handle, and later replaced, so as to wash the pan without exposing the handle electronics to washing environments. The handle electronics preferably have a display to show desired information, e.g., food temperature, to the user. Preferably, a processor is included with the handle electronics to process signals from the sensors to provide food characteristics, e.g., doneness. Sensitive electronics are preferably included within the handle electronics, and the handle electronics are preferably thermally shielded from frying temperatures in the pan, so as to protect electronic components. User inputs to the processor (i.e., via the handle electronics) provide for selecting doneness (e.g., “well-done”) and food type (e.g., meat, poultry, eggs) options.  
           [0004]    In one aspect, the invention includes a digital frying pan, sensor electronics and a LCD display. The sensor electronics convert an analog sensor signal (for example, indicating pan temperature) into a digital signal for display at the LCD display of temperature in either Fahrenheit or Centigrade. A user of the digital frying pan preferably reads the display when facing the handle, and thus the display is preferentially oriented for this view. The information displayed preferably changes as pan or food temperature changes. In addition the display also preferably provides an analog representation of temperature, such as a bar graph. In one aspect, at least part of the sensor electronics are contained within removeable module, such that the module may be removed during washing of the digital frying pan so as not to damage sensitive electronics. In another aspect, the LCD display is also incorporated into the removeable module.  
           [0005]    In yet another aspect, the invention provides a remote food doneness system. The system couples with a wall or other surface and has a line of sight to cooking food such as within a frying pan. The system includes optics and one or more thermal sensing detectors; the optics image the cooking food to the thermal sensing detectors; and processing electronics within the remote food doneness system process signals from the detectors to determine food characteristics, e.g., temperature. In one embodiment, a processor and memory within the remote food doneness system stores information such as food items (e.g., eggs, chicken, beef) and corresponding food doneness and temperature settings. A user interface permits a user of the system to select food doneness options. The system preferably includes an audible or visual indicator to warn of programmed events, e.g., when food viewed by the system has reached desired temperatures or doneness. The system in one embodiment, for example, may thus “view” cooking eggs and warn a user desiring the eggs that the eggs are “over easy”.  
           [0006]    In one aspect, an electronic frying pan system is provided. The system includes a pan for cooking food and a handle connected to the pan for manipulating the pan. One or more temperature sensors connect with the pan to generate signals indicative of one or more characteristics of the pan, such as temperature. Indication electronics disposed with the handle connect with the sensors and disposed to provide at least one indication of the characteristics to a user of the pan.  
           [0007]    In one aspect, the indication electronics includes a liquid crystal display to display the one or more characteristics to the user. By way of example, pan temperature is relayed to the user. Pan temperature of one aspect is calibrated to a food temperature as the food is generally not directly adjacent to a temperature sensor.  
           [0008]    In one aspect, the indication electronics include a processor to process the signals to associate food characteristics corresponding to food cooking within the pan. Food characteristics can include food doneness.  
           [0009]    In another aspect, a user interface is included with the frying pan to provide for selecting one of several food types, such that the processor generates food characteristics as a function of food type. Similarly, food temperatures may be selected in another aspect.  
           [0010]    In a preferred aspect, the indication electronics are detachable and alternatively attachable with the handle, such that the pan may be washed without the indication electronics.  
           [0011]    In still another aspect, the indication electronics have voice synthesis electronics to speak at least the one indication to the user.  
           [0012]    Preferably, the indication electronics include a memory element for storing food doneness versus temperature settings for one or more food types.  
           [0013]    In yet another aspect, an audible alarm is coupled with the indication electronics to audibly inform a user of the pan system of one of temperature and food doneness of food within the pan.  
           [0014]    In one aspect, the indication electronics include a calibration memory to couple the indication electronics with a plurality of different size pans, such that the indication electronics provide calibrated information for the different size pans.  
           [0015]    The invention of another aspect provides a method of cooking food in a frying pan, including the steps of: sensing temperature of the frying pan, processing pan temperature to determine one or more of food doneness and food temperature, and informing a user of the pan of the food doneness and/or food temperature.  
           [0016]    The method can also include the steps of decoupling processing electronics from the frying pan prior to washing the pan and alternatively coupling the processing electronics with the frying pan prior to use.  
           [0017]    The method can also include the steps of decoupling processing electronics from the frying pan and coupling the processing electronics with a second pan having a different size from the frying pan, and selecting calibration data within the processing electronics to provide calibrated information for the different size second pan.  
           [0018]    In another aspect, the invention provides a method of remotely monitoring temperature of food, including the steps of: imaging the food onto a thermal sensor, processing signals from the thermal sensor to determine a temperature of the food, and informing the user of the temperature.  
           [0019]    The method of this aspect preferably includes the step of attaching a housing coupled with the sensor to a surface in line of sight from the food.  
           [0020]    In yet another aspect, the method includes the further step of imaging the food onto a CCD to display an image of the food to the user so as to physically arrange appropriate mounting of the housing to image the food onto the thermal sensor.  
           [0021]    The invention of one aspect calibrates a thermal sensor arranged to sense temperature at the side of the pan. Since the side of the pan generally has a different temperature than the center of the pan, where food cooks, the invention calibrates the temperature taken at the side of the pan to correlate to the center of the pan. Software with the electronics module provides smoothing of the data based on rate of change of temperature at the side of the pan. This provides an average rate of change usable to compensate for temperatures in the pan center.  
           [0022]    The invention is next described further in connection with preferred embodiments, and it will become apparent that various additions, subtractions, and modifications can be made by those skilled in the art without departing from the scope of the invention. 
       
    
    
     BRIEF DESCRIPTION OF ILLUSTRATED EMBODIMENTS  
       [0023]    A more complete understanding of the invention may be obtained by reference to the drawings, in which:  
         [0024]    [0024]FIG. 1 shows one electronic frying pan constructed according to the invention;  
         [0025]    [0025]FIG. 2 shows a partial cross-sectional view of the handle and pan of FIG. 1;  
         [0026]    [0026]FIG. 3 shows one block diagram of circuitry suitable for use with an electronic pan of FIG. 2;  
         [0027]    [0027]FIG. 4 shows one electronics handle of the invention; FIG. 4A shows an end view of the handle of FIG. 4; FIG. 4B shows a cross-sectional side view of the handle of FIG. 4;  
         [0028]    [0028]FIG. 5 shows one remote food doneness system constructed according to the invention; and  
         [0029]    [0029]FIG. 6 schematically shows an electronic block diagram of the system of FIG. 5. 
     
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT  
       [0030]    [0030]FIG. 1 shows an electronic frying pan  10  constructed according to the invention with (a) a thermally conductive pan  12  and (b) a handle  14 . One or more temperature sensors  11  coupled with pan  12  connect to an electronics module  16  in handle  14 . Electronics module  16  preferably includes display  18  to show a user of pan  10  characteristics associated with pan  12  or food (in the form of an egg)  20  within pan  12 . Electronics module  16  includes a processor such as a microprocessor and preferably includes memory to store food doneness options and user selections. A user interface  22  provides for user input to select various characteristics and functions of electronics module  16 . Display  18  may show digital temperature  18   a , a bar graph representation  18   b  of temperature or doneness, or other information. As described below, electronics module  16  preferably detaches from pan  10  so that pan  10  is washable without module  16  attached thereto. Teflon wires preferably seal the remaining portions of handle  14  to prevent liquids from entering electronics remaining after removal of module  16 .  
         [0031]    Temperature sensors  11  include, for example, a thermistor or thermocouple. Thermocouple  11  couples to electronics module  16  via electronic or thermal conductive path  24 ; path  24  is chosen as a matter of design choice as a medium to transfer data or signals from sensor  11  to module  16 . Preferably, stainless steel is used to provide contact between module  16 , path  24  and sensors  11 . FIG. 1 shows one temperature thermocouple  11  coupled with conductive pan  12 , though additional sensors  11  may be placed about pan  12  as a matter of design choice. For example, one or more additional temperature sensors may be placed at different locations  11   a ; sensors at locations  1   a  also connect to module  16  and may provide more representative temperature data for food  20 . Any temperature sensor  11  may be calibrated to correspond to a temperature profile experienced by food  20 , even though sensor  11  is not directly adjacent food  20 . Typical pan calibrations are for pans that are eight, ten or twelve inches in diameter.  
         [0032]    In operation, a user of pan  10  selects pre-programmed temperature settings or programs personal settings to cook food  20  in a desired manner. For example, such a user may select 300 degrees F. for eggs, 340 degrees F. for bacon, 360 degrees F. for burgers and pork chops, 380 degrees F. for pancakes, and 400-420 degrees F. for steak. Other options are of course available without departing from the scope of the invention. In the preferred embodiment, display  18  displays the temperature of pan  12  in Centigrade or Fahrenheit. Various cooking levels are preferably selectable at handle  14 . When a cooking level is selected, a microprocessor in module  16  provides a signal converted to display  18  that informs the user that the temperature is at his desired chosen cooking level.  
         [0033]    [0033]FIG. 2 shows a partial cross-sectional view of pan  10  of FIG. 1. Those skilled in the art should appreciate that the mechanical design of pan  10  is a matter of design choice and that other configurations may be functionally arranged without departing from the scope of the invention.  
         [0034]    [0034]FIG. 3 schematically illustrates circuitry  50  suitable for use with frying pan  10  of FIG. 1. An LCD display  52  may for example be used as display  18 ; an LCD controller  53  generally controls display  52  as known in the art. Dotted line  54  indicates one practical partitioning of components of circuitry  50  that may be conveniently contained within one package. A thermocouple or thermistor  56  may serve in function as one of the sensors  11  to generate signals concerning characteristics of the pan and/or food within pan  12 . A voltage amplifier  57  may be used to boost sensor signals, as desired or needed. An A-D converter  59  is generally used when sensor  56  drives an analog signal. In one embodiment, the handle electronics module can include voice synthesis electronics  58  used to capture human voice commands for pan or food characteristics made by a user of pan  10 . Normally, however, users input instructions to circuitry  50  via input buttons  60  (e.g., for user interface buttons  22 , FIG. 1) so as to select desired food or doneness characteristics. A microcontroller  64  provides for overall function and command intelligence of circuitry  50 ; for example microcontroller  64  adjusts cooking time based on surface temperature of pan  12 , FIG. 1. A crystal  66  provides for timing in circuitry  50 .  
         [0035]    [0035]FIGS. 4, 4A,  4 B show one handle  70  constructed according to the invention and suitable for use an electronic frying pan  71  (shown only partially, for purposes of illustratinon) such as pan  10 , FIG. 1. A display  72  shows food or pan characteristics. Preferably the handle electronics are in the form of a removable control module  74 , as shown; a module alignment nub  75 , ball shap  77 , and lip  79  may be used to facilitate removing from, and alternatively replacing module  74  within, handle  70 . A battery  76 , e.g., a 2450 Lithium battery, fits within handle  74 ; battery  76  may be removed from module  74  via access door  81 . User interface buttons  78   a ,  78   b  provide for “advance” and “set” menu options, respectively. A hang hole  80  permits hanging of handle  70  on a hook. A warning buzzer  82  provides an audible warning of programmed food doneness sensed by temperature sensors coupled with module  74  via communications lines  84 .  
         [0036]    The invention thus provides several advantages. By way of example, eggs are one food difficult to cook with certainty as to whether they are well done, over easy or medium. The invention provides for recalling temperature for desired egg doneness; and a user need not rely on stove temperature settings. The microcontroller of the preferred embodiment automatically signals the user (e.g., via buzzer  82 , FIG. 4) when the desired egg doneness is reached. Since the display can include an analog representation of doneness, e.g., via a bar graph or tachagraphic display, then the user may also watch food approach the desired doneness, so as not to be surprised. User selections at the user interface (e.g., by pressing button  22 , FIG. 1) provide for selecting doneness options (e.g., over easy) and food types (e.g., eggs); or a user can select custom temperatures. In a further advantage, the replaceable module (e.g., module  16 , FIG. 1) may be used in an array of pans of different size—but with a common electronics module. When the module is coupled with a certain pan size, the user preferably sets pan size through the same user interface so as to adjust any calibrations to temperature sensors with the particular pan.  
         [0037]    [0037]FIG. 5 shows a remote food doneness system  100  constructed according to the invention. System  100  is constructed and arranged to attach to surfaces  102  near to cooking food  104 , such as food on stove  106  and within frying pan  108 . By way of example, system  100  attaches to surface  102  via magnets  110  coupled with system  100 ; surfaces  102  are typically metallic surfaces that are part of stove  106 . In operation, system  100  views food  104  through a field of view  105 ; system  100  then monitors food doneness and/or temperature of food  104  to provide an indication  112  of doneness and/or temperature to a user. Typically, indication  112  is an audible sound or light made, respectively, from a speaker or LED  114 . System  100  thus provides operation similar to the digital frying pans of FIGS.  1 - 4 ; however system  100  functions remotely from food  104 .  
         [0038]    [0038]FIG. 6 shows a block schematic of system  100 ; those skilled in the art should appreciate that elements of system  100 , as shown in FIG. 6, may be arranged in different ways, or through different components, without departing from the scope of the invention. An infrared optically powered element (e.g., a mirror or Germanium lens)  122  images food  104  onto a thermal detector  124  (e.g., a bolometer), as shown by optical imaging lines  125 . A visible optically powered element (e.g., a quartz lens)  126  images food  104  onto a CCD array  128 , as shown by optical imaging lines  129 . A PCB and processing section  130  converts signals from CCD array  128  to data for LCD  130 ; PCB and processing section  130  converts signals from thermal detector  124  to temperature data indicating a temperature of food  104 ; a user may view LCD  132  to view what food  104  system  100  monitors; specifically, by reviewing LCD  132  a user may position system  100  appropriately on surface  102  so as to appropriately image food  104  to thermal detector  124 . A user interface provides for inputting selections for temperature and food doneness to system  100 ; preferably PCB and processing section  130  includes memory to store food doneness options and food types, similar to system described above in FIGS.  1 - 4 . Once a selected temperature or food doneness is reached, for food  104 , system  100  informs the user of this through indicator  114  (e.g., a buzzer or LED). In this way, a user of system  100  can monitor food doneness and temperature for a food remotely and conveniently. As those skilled in the art understand, determining temperature of food  104  via thermal detectors works best when a reference temperature is available; thus preferably thermal detector  124  includes at least two detectors, one to receive thermal energy from food  104  and one to receive thermal energy from a reference temperature such as the inside of system  100 , which is generally at room temperature. Data from the two detectors  124  may then be compared (in PCB and processing section  130 ) to determine temperature of food  104 . Other calibration techniques for determining absolute temperature may also be used.  
         [0039]    Those skilled in the art should appreciate that system  100  can utilize a single infrared CCD to provide both imaging for LCD display  130  and temperature monitoring of food  104 . In such an embodiment, separate lens  126  and CCD array  128  are not necessary.  
         [0040]    The invention thus attains the objects set forth above, among those apparent from the preceding description. Since certain changes may. be made in the above methods and systems without departing from the scope of the invention, it is intended that all matter contained in the above description or shown in the accompanying drawing be interpreted as illustrative and not in a limiting sense. It is also to be understood that the following claims are to cover all generic and specific features of the invention described herein, and all statements of the scope of the invention which, as a matter of language, might be said to fall there between.