FIELD

[0001] The field of the invention relates to systems and methods for monitoring cooktops. More specifically to systems and methods for detecting cooktop events, such as unsafe use of a cooktop.

INTRODUCTION

[0002] Cooktop safety systems for detecting unsafe use of a cooktop are known in the art. Further, cooktop safety systems which may trigger an alarm and/or activate the discharge of a fire retardant are known. However, the sensors used by known cooktop safety systems and the data collection and analysis methods implemented by these systems may incorrectly predict cooktop events which can lead to false alarms and/or unwanted discharge of fire retardant.

[0003] An example of a known cooktop safety system is described in U.S. Patent No. 8,530,842 to Has et al. (Has). Has describes a hob device that has a monitoring unit to monitor a cooking area of a hob. The monitoring unit includes a sensor array of multiple infrared sensors to record infrared light.

SUMMARY

In one aspect, a cooktop safety system is provided. The cooktop safety system includes a surface monitoring unit, which in turns includes: a controller; a sensor for monitoring a cooktop surface and providing image data; a controller coupled to the sensor to receive the image data and to identify a cooktop event by comparing the image data to previously recorded image data corresponding to cooktop events; and a cooktop event indication system coupled to the controller providing indication that a cooktop event has been identified.

[0004] In some embodiments, the sensor may be an infrared sensor array.

[0005] In some embodiments, the cooktop surface monitoring system may further comprise a microphone coupled to the controller to provide audio data and wherein the controller is configured to compare the audio data with previously recorded audio data to refine the identification of a cooktop event.

[0006] In some embodiments, the cooktop surface monitoring system may further comprise a microphone coupled to the controller to provide audio data and wherein the controller is configured to identify a user command in the audio data and to modify the operation of the cooktop surface monitoring system in response to the user command.

[0007] In some embodiments, the cooktop event identification system may be a visual indication system, an audible indication system, may transmit a notification to a user device or a combination thereof.

[0008] In some embodiments, the controller may be configured to give at least two levels of indications, including an intermediate level alert indication and a high level alert indication.

[0009] In some embodiments, the cooktop surface monitoring system may further include a switch coupled to the controller to provide a switch input and wherein the controller is configured to modify the operation of the cooktop surface monitoring system in response to a switch input.

[0010] In another aspect, a method of monitoring a cooktop for flames emanating from a food item in cookware heated by the cooktop is provided. The method includes: providing a cooktop safety device above a cooktop surface of the cooktop, the cooktop safety device having thermopile infrared sensor for collecting thermal data from a monitoring area which includes at least a portion of the cooktop surface; operating the thermopile infrared sensor to: collect infrared radiation emitted from within the monitoring area; and convert the infrared radiation emitted from within the monitoring area to temperature data; operating a processor to detect perturbations in the temperature data, where perturbations in the temperature data indicate the presence of flames; and performing a cooktop event response when the processor detects perturbations in the temperature data.

[0011] In some embodiments, the cooktop event response may be at least one of triggering a cooktop event alarm, activating a cooktop event prevention system, and logging the cooktop event in a cooktop event database.

[0012] In some embodiments, the monitoring area may include a region in front of the cooktop and the method may further include operating the processor to detect a presence of a human in the region in front of the cooktop. [0013] In some embodiments, the method may further include: performing a first cooktop event response when the processor detects perturbations in the temperature data and does not detect the presence of the human in the region in front of the cooktop; or performing a second cooktop event response when the processor detects perturbations in the temperature data and detects the presence of the human in the region in front of the cooktop; In some embodiments, the first cooktop event response may be different from the second cooktop event response.

[0014] In some embodiments, when the processor detects the presence of a human in the region in front of the cooktop, the method may further include determining if the human is an adult or a child.

[0015] In some embodiments, the second cooktop event may be a third cooktop event when the processor detects perturbations in the temperature data; the processor detects the presence of the human in the region in front of the cooktop; and the processor detects the human is an adult; or the second cooktop event may be a fourth cooktop event when the processor detects perturbations in the temperature data; the processor detects the presence of the human in the region in front of the cooktop; and the processor detects the human is a child.

[0016] In some embodiments, the third cooktop event may be different from the fourth cooktop event.

[0017] In some embodiments, the fourth cooktop event may be the same as the first cooktop event.

[0018] In another aspect, a method of monitoring a cooktop for flames emanating from a food item in cookware heated by the cooktop is provided. The method including: providing a cooktop safety device above a cooktop surface of the cooktop, the cooktop safety device having a camera for taking images of a monitoring area which includes at least a portion of the cooktop surface; operating a processor having image recognition software to detect flames in the images; and performing a cooktop event response when the processor detects flames in the images. [0019] In some embodiments, the cooktop event response may be at least one of triggering a cooktop event alarm, activating a cooktop event prevention system, and logging the cooktop event in a cooktop event database.

[0020] In some embodiments, the monitoring area may include a region in front of the cooktop and the method may further include operating the processor to detect a presence of a human in the region in front of the cooktop.

[0021 ] In some embodiments, the method may further include: performing a first cooktop event response when the processor detects flames in the images and does not detect the presence of the human in the region in front of the cooktop; or performing a second cooktop event response when the processor detects flames in the images and detects the presence of the human in the region in front of the cooktop. In some embodiments, the first cooktop event response may be different from the second cooktop event response.

[0022] In some embodiments, when the processor detects the presence of a human in the region in front of the cooktop, the method may further include determining if the human is an adult or a child.

[0023] In some embodiments, the second cooktop event may be a third cooktop event when the processor detects flames in the images; the processor detects the presence of the human in the region in front of the cooktop; and the processor detects the human is an adult; or the second cooktop event may be a fourth cooktop event when the processor detects flames in the images; the processor detects the presence of the human in the region in front of the cooktop; and the processor detects the human is a child.

[0024] In some embodiments, the third cooktop event may be different from the fourth cooktop event.

[0025] In some embodiments, the fourth cooktop event may be the same as the first cooktop event.

[0026] In another aspect, a method of classifying a cooktop user on a safety risk index is provided. The method including: collecting at least one safety risk index factor about the cooktop user; monitoring a cooktop associated with the cooktop user for at least one cooktop event; logging the at least one cooktop event in a cooktop event database for that cooktop user; providing a criteria weight to each of the collected safety risk index factors and each cooktop event of the at least one cooktop event logged in the cooktop event database calculating a safety risk index score based on the criteria weight provided; and classifying the cooktop user on the safety risk index based on the safety risk index score.

[0027] In some embodiments, the at least one safety risk index factor may be at least one of: (a) at least one of average date, time, and duration of cooktop operation; (b) building geographic location; (c) building type; (d) unit location within the building; (e) type of cooktop; and (f) age of cooktop.

[0028] In some embodiments, when the at least one cooktop event is at least two cooktop events, the at least one safety risk index factor may include a frequency of the cooktop events.

[0029] In another aspect, a method of monitoring a range having a cooktop and an oven for an oven event is provided. The method includes: operating a cooktop surface monitoring unit to collecting thermal data from a monitoring area which includes at least a portion of the cooktop surface; operating a range power monitoring unit to collect utility draw data to the range; and performing an oven event response when the range power monitoring unit detects utility draw to the range and the cooktop surface monitoring unit does not detect heating of the cooktop surface.

[0030] In some embodiments, the oven event response may be at least one of triggering an oven event alarm, activating an oven event prevention system, and logging the oven event in an oven event database.

[0031] In some embodiments, the monitoring area may include a region in front of the range and the method may further include operating a processor to detect a presence of a human in the region in front of the cooktop.

[0032] In some embodiments, the method may further include: performing a first oven event response when the range power monitoring unit detects utility draw to the range; the cooktop surface monitoring unit does not detect heating of the cooktop surface; and the processor does not detect the presence of the human in the region in front of the cooktop; or performing a second oven event response when the range power monitoring unit detects utility draw to the range; the cooktop surface monitoring unit does not detect heating of the cooktop surface; and the processor detects the presence of the human in the region in front of the cooktop.

[0033] In some embodiments, the first cooktop event response may be different from the second cooktop event response.

[0034] In some embodiments, the processor may detect the presence of a human in the region in front of the cooktop and the method may further include determining if the human is an adult or a child.

In some embodiments, the second cooktop event may be a third cooktop event when the range power monitoring unit detects utility draw to the range; the cooktop surface monitoring unit does not detect heating of the cooktop surface; the processor detects the presence of the human in the region in front of the cooktop; and the processor detects the human is an adult; or the second cooktop event may be a fourth cooktop event when the range power monitoring unit detects utility draw to the range; the cooktop surface monitoring unit does not detect heating of the cooktop surface; the processor detects the presence of the human in the region in front of the cooktop; and the processor detects the human is a child.

[0035] In some embodiments, the third cooktop event may be different from the fourth cooktop event.

[0036] In some embodiments, the fourth cooktop event may be the same as the first cooktop event.

[0037] In another aspect, a method of determining if the contents of cookware being heating on a cooktop is a volume of liquid and if that volume of liquid is a volume of oil or a volume of water is provided. The method including: heating the cookware and the contents on a cooktop; operating a thermopile infrared sensor over a period of time to: collect infrared radiation emitted from the cookware and the contents; and convert the infrared radiation emitted from the cookware and the contents to temperature data; operating a processor to: create a measured temperature vs. time curve with the temperature data; comparing the measured temperature vs. time curve to at least one predetermined temperature vs. times curve for liquids; and determine a maximum plateaued temperature in the temperature data wherein when the measured temperature vs. time curve matches a predetermined temperature vs. time curve of the at least one predetermined temperature vs. time curves for liquids and the maximum plateaued temperature in the temperature data is above 100 degrees Celsius the contents of the cookware is oil, when the measured temperature vs. time curve matches a predetermined temperature vs. time curve of the at least one predetermined temperature vs. time curves for liquids and the maximum plateaued temperature in the temperature data is below 100 degrees Celsius the contents of the cookware is water.

DRAWINGS

[0038] For a better understanding of the described embodiments and to show more clearly how they may be carried into effect, reference will now be made, by way of example, to the accompanying drawings in which:

[0039] FIG. 1A is a sideview of a cooktop and an example cooktop safety device;

[0040] FIG. 1 B is a front view of the cooktop and the cooktop safety device of FIG. 1A;

[0041] FIG. 2 is a sideview of an alternative embodiment of a cooktop and cooktop safety device;

[0042] FIG. 3 is a sideview of a range hood and a cooktop safety device;

[0043] FIG. 4 illustrates a cooktop surface monitoring unit;

[0044] FIGS. 5-8 illustrate another cooktop surface monitoring unit;

[0045] FIG 9 illustrates the cooktop surface monitoring unit of FIGS 5-8 mounted adjacent a cooktop in several positions; and

[0046] FIG. 10 is a graph showing temperature vs. time data of a food item as the food item is heated.

[0047] The drawings included herewith are for illustrating various examples of articles, methods, and apparatuses of the teaching of the present specification and are not intended to limit the scope of what is taught in any way. DESCRIPTION OF VARIOUS EMBODIMENTS

[0048] Numerous embodiments are described in this application and are presented for illustrative purposes only. The described embodiments are not intended to be limiting in any sense. The invention is widely applicable to numerous embodiments, as is readily apparent from the disclosure herein. Those skilled in the art will recognize that the present invention may be practiced with modification and alteration without departing from the teachings disclosed herein. Although particular features of the present invention may be described with reference to one or more particular embodiments or figures, it should be understood that such features are not limited to usage in the one or more particular embodiments or figures with reference to which they are described.

[0049] The terms "an embodiment," "embodiment," "embodiments," "the embodiment," "the embodiments," "one or more embodiments," "some embodiments," and "one embodiment" mean "one or more (but not all) embodiments of the present invention(s)," unless expressly specified otherwise.

[0050] The terms "including," "comprising" and variations thereof mean "including but not limited to," unless expressly specified otherwise. A listing of items does not imply that any or all of the items are mutually exclusive, unless expressly specified otherwise. The terms "a," "an" and "the" mean "one or more," unless expressly specified otherwise.

[0051] As used herein and in the claims, two or more parts are said to be "coupled", "connected", "attached", or "fastened" where the parts are joined or operate together either directly or indirectly (i.e., through one or more intermediate parts), so long as a link occurs. As used herein and in the claims, two or more parts are said to be "directly coupled", "directly connected", "directly attached", or "directly fastened" where the parts are connected in physical contact with each other. As used herein, two or more parts are said to be "rigidly coupled", "rigidly connected", "rigidly attached", or "rigidly fastened" where the parts are coupled so as to move as one while maintaining a constant orientation relative to each other. None of the terms "coupled", "connected", "attached", and "fastened" distinguish the manner in which two or more parts are joined together. [0052] As used herein and in the claims, a group of elements are said to “collectively” perform an act where that act is performed by any one of the elements in the group, or performed cooperatively by two or more (or all) elements in the group.

[0053] As used herein and in the claims, a first line or axis is said to be “perpendicular” to a second line or axis in three dimensional space when the second line or axis is parallel to or collinear with an imaginary line that intersects the first line at a 90 degree angle, or within an angle of about 5 degrees of parallel to or collinear with the imaginary line.

[0054] As used herein and in the claims, a first element is said to extend

“transverse” to a second element, where the first element extends within 45 degrees of perpendicular to the second element.

[0055] Some elements herein may be identified by a part number, which is composed of a base number followed by an alphabetical or subscript-numerical suffix (e.g., 112a, or 112i). Multiple elements herein may be identified by part numbers that share a base number in common and that differ by their suffixes (e.g., 112i, 1122, and 1123). All elements with a common base number may be referred to collectively or generically using the base number without a suffix (e.g., 112).

[0056] It should be noted that terms of degree such as "substantially", "about", and "approximately" as used herein mean a reasonable amount of deviation of the modified term such that the end result is not significantly changed. These terms of degree may also be construed as including a deviation of the modified term, such as by 1 %, 2%, 5% or 10%, for example, if this deviation does not negate the meaning of the term it modifies.

[0057] Furthermore, the recitation of numerical ranges by endpoints herein includes all numbers and fractions subsumed within that range (e.g., 1 to 5 includes 1 , 1.5, 2, 2.75, 3, 3.90, 4, and 5). It is also to be understood that all numbers and fractions thereof are presumed to be modified by the term "about" which means a variation of up to a certain amount of the number to which reference is being made if the end result is not significantly changed, such as 1 %, 2%, 5%, or 10%, for example. General Description of a Cooktop Safety Device

[0058] A cooktop safety device may monitor a cooktop and/or a surrounding area of the cooktop (e.g., the space in front of the cooktop) and may be operable to detect a cooktop event. As used herein, the term “cooktop event” means any detectable activity or inactivity on, near, or relating to the cooktop that may be generally understood as unsafe. Examples of cooktop events include, but are not limited to, unattended cooking, high temperature heating element(s), high temperature cookware and/or food contained by the cookware, burning food, undercooked food, heating element left on, child operating cooktop, and imminent unsafe cooking situations, etc.

[0059] The cooktop to be monitored may be any cooktop known in the art. For example, the cooktop may be a gas cooktop, an electric cooktop (radiant or coil), an induction cooktop, or any combination thereof. The cooktop may be a stand-alone unit or may be built into a range (i.e. , a single unit having an oven and a cooktop). The cooktop may have any number of heating elements. The heating elements may be of any shape and size suitable for heating cookware. The heating elements may or may not be the same shape and size as an adjacent heating element.

[0060] T o detect a cooktop event, the cooktop safety device may collect and process data. Any processor suitable for analyzing the data collected may be used. Optionally, the processor may include machine learning capabilities. Any sensor or combination of sensors suitable for collecting data relating to the operation of the cooktop may be used. The sensors may collect data by (a) monitoring inputs and/or outputs from the cooktop (e.g., utility draw (i.e., the amount of electricity or gas provided to the cooktop), cooktop surface temperature, etc.); (b) monitoring the environment surrounding the cooktop (e.g., presence of a user in an area in front of the cooktop); and/or (c) monitoring mechanical and/or electrical signals within the cooktop (i.e., the sensor(s) may be integrated into the cooktop).

[0061] In some examples, a user of the cooktop safety device may provide data relating to the cooktop, characteristics of the frequent users of the cooktop, and/or characteristics of the area surrounding the cooktop to the cooktop safety device. For example, a user of the cooktop safety device may provide the cooktop safety device with data such as cooktop type (e.g., gas, electric, or induction), cooktop make and/or model, permitted use of the cooktop by a child, etc. Optionally, this data may be provided to the cooktop safety device during a calibration/installation session.

[0062] It will be appreciated that the cooktop events detectable by the cooktop safety device may be dependent on (a) the type of sensor(s) include in the cooktop safety device; (b) the type of cooktop being monitored; and/or (c) the type of data provided to the cooktop safety device by the user. For example, in embodiments of the cooktop safety device that include only one sensor for measuring a utility draw by the cooktop, the cooktop safety device may not be able to detect if the cooktop is being operated by a child. As a second example, in embodiments of the cooktop safety device that include only one sensor for measuring the temperature of the cooktop surface, the cooktop safety device may not be able to detect if an induction cooktop has been left on without any cookware thereon (while not inherently dangerous, this may be a cooktop event because an operator may place cookware or other ferrous items onto the cooktop assuming that it is off).

[0063] The cooktop safety device may only collect data relating to cooktop safety when the cooktop is powered on. Alternatively, the cooktop safety device may collect data relating to cooktop safety when the cooktop is powered off and on. In any case, the cooktop safety device may periodically and/or continuously collect data. That is, for example, when the cooktop is powered on the cooktop safety device may periodically or continuously collect data relating to cooktop safety.

[0064] It will be appreciated that in embodiments where data relating to cooktop safety is only collected when the cooktop is powered on, it may be required to periodically collect at least one form of power status data to determine whether the cooktop is powered on.

[0065] If the cooktop safety device only collects cooktop safety data when the cooktop is powered on, the cooktop safety device may include any sensor known in the art suitable to determine when the cooktop is powered. For example, a sensor may detect a utility draw to the cooktop which may indicate that the cooktop is powered on. Alternatively, a thermal sensor may scan the cooktop surface periodically and may signal the cooktop safety device that the cooktop is powered on when an elevated temperature is detected. It has been found that a thermal sensor may scan the cooktop surface to determine a power state every one minute, two minutes, three minutes, four minutes, or five minutes and not reduce the effectiveness of the cooktop safety device as cooktop events typically do not occur within the first five minutes of using of the cooktop.

[0066] Optionally, the cooktop safety device may include an override feature to temporarily pause monitoring of the cooktop and/or surrounding area for a cooktop event. It may be desirable to pause monitoring for cooktop events if/when the user of the cooktop intends on intentionally operating the cooktop in a manner that may generally be understood to be unsafe. For example, a user may override the cooktop safety device if they intend on flambeing their food. When the user of the cooktop overrides the cooktop safety device, the cooktop safety device may (a) temporarily pause data collection; or (b) temporarily pause operations of the cooktop safety device that may occur following the detection of a cooktop event (described in more detail below). In some examples, the cooktop safety device may include an override button in the cooktop safety device housing. Alternatively, or in addition, the cooktop safety device may receive a wireless override signal from, for example, a mobile device.

[0067] The cooktop safety device may be an “aftermarket” device or may be built into the cooktop and/or range system by the cooktop manufacturer. It will be appreciated that when the cooktop safety device is built into the cooktop and/or range system, the cooktop safety device may receive data directly from sensors built into the cooktop. However, it is to be understood that in embodiments in which the cooktop safety device is an aftermarket device, the cooktop safety device may still receive data from sensors built into the cooktop. For example, the cooktop may be configured to transmit data to a smart home hub and/or a mobile device. Accordingly, this data may be transmitted to the cooktop safety device. As a second example, the cooktop safety device may be wiredly connectable to the cooktop to intercept and retransmit data signals (mechanical or electrical) within the cooktop (e.g., can be wired into the cooktop to receive data from sensors within the cooktop such as heating element temperature settings). [0068] When the cooktop safety device detects a cooktop event, the cooktop safety device may perform a cooktop event response. Examples of cooktop event responses include, but are not limited to, (a) giving an indication of a cooktop event, such as triggering a cooktop event alarm (e.g., setting off an audible alarm, sending a SMS message (to at least one frequent user of the cooktop and/or a landlord), sending an email, pushing a notification, etc.); (b) activating a cooktop event prevention system (e.g., cutting utility supply to the cooktop, discharging a fire retardant); and/or (c) logging the cooktop event in a cooktop event database.

[0069] Optionally, the cooktop safety device may be wiredly or wirelessly connectable with other systems within the building that houses the cooktop (e.g., home, office, restaurant, etc.). For example, the cooktop safety device may be wirelessly connectable with smoke detectors in a user’s home.

[0070] The cooktop safety device may be positionable at any location about the cooktop suitable for collecting data about the cooktop. In some examples, the cooktop safety device may comprise multiple units, each of which may be positioned at any location about the cooktop suitable for collecting data about the cooktop. When the cooktop safety device includes multiple units, the units may be in communication (wired or wireless) with each other or may be standalone units.

[0071] Referring now to FIG. 1A, an example of a cooktop safety device 100 is illustrated. In the example illustrated, the cooktop safety device 100 includes a cooktop surface monitoring unit 102 and a cooktop power monitoring unit 104. It will be appreciated that in other embodiments, the cooktop safety device 100 may include only a cooktop surface monitoring unit 102, only a cooktop power monitoring unit 104, or additional units (i.e., sensors) that are not shown.

[0072] As shown in FIGS. 1A and 1 B, the cooktop surface monitoring unit 102 may be positioned on a wall 106 behind the cooktop 108. The cooktop surface monitoring unit 102 may have any shape or size suitable to position sensor(s) in a location where they are able to collect data about the cooktop 108 and/or surrounding area. In the example illustrated, the cooktop surface monitoring unit 102 has a distal end 110 that extends away from the wall 106. It may be desirable for the cooktop surface monitoring unit 102 to have a distal end 110 that extends away from the wall 106 so that sensor(s) 112 can be positioned in the distal end 110. In some installations, the cooktop surface monitoring unit 102 may be positioned toward a central axis 114 of the cooktop surface 116. While it is not necessary, it has been found that the data collection capabilities of some sensors may be enhanced by positioning those sensors toward the central axis 114 of the cooktop surface (e.g., a thermopile infrared array for detecting temperatures across or above the cooktop surface or flames on or above the cooktop surface). The angle a at which the distal end 110 is rotated from the wall 106 may range from 0 degrees to 180 degrees. The distance D1 the distal end 110 of the cooktop surface monitoring unit 102 may extend away from the wall 106 may range from flush with the wall 106 up to a depth D2 of the cooktop 108.

[0073] The cooktop power monitoring unit 104 of the cooktop safety device 100 is positioned between a wall outlet 116 and a power cord 118 of the cooktop 108. Accordingly, the cooktop power monitoring unit 104 may monitor the amount of electric power being drawn by the cooktop 108 over time. It will be appreciated that a similar sensor could be positioned along a gas line which supplies gas to a gas cooktop.

[0074] Alternatively, or in addition to monitoring utility draw (i.e. either electric power draw or gas draw), the cooktop power monitoring unit 104 may be configured to receive a shut-off signal from the cooktop safety device processor and to cut utility supply to the cooktop. Optionally, the cooktop power monitoring unit 104 may be configured to receive a shut-off signal from a third-party device, such as, for example, a mobile device. In this example, a user may signal the cooktop power monitoring unit 104 to cut utility draw to the cooktop from a remote location. Optionally, the cooktop power monitoring unit 104 may include a transmitter for sending utility draw data to a third-party device, such as, for example, a mobile device. In some embodiments, the cooktop power monitoring unit 104 may transmit utility draw data to the cooktop surface monitoring unit 102, which may then transmit utility draw information to a user’s mobile device.

[0075] Referring now to FIG. 2, a second example of a cooktop safety device 100 is shown. In the example illustrated, the cooktop safety device is located on a range hood 120 positioned above the cooktop 108. It is to be understood that the cooktop safety device 100 may be positioned at any location on the range hood 120 and/or may comprise multiple units positioned at various locations on the range hood 120.

[0076] Referring now to FIG. 3, the cooktop safety device 100 may include a cleaning system 130 suitable for keeping at least one sensor 112 of the cooktop safety device 100 clean. It may be desirable for the cooktop safety device 100 to include a cleaning system 130 for keeping at least one sensor 112 clean because when cooking, grease-laden vapors may be produced which, depending on the type and location of the sensor 112, may coat the sensor 112 affecting its operation or potentially rendering it inoperable.

[0077] In the example illustrated in FIG. 3, the cleaning system 130 includes a fan 132. As shown, the fan 132 may blow air over the sensor 112a and may create an air-curtain 134 around the sensor 112a to reduce or prevent grease build up on the sensor 112a.

[0078] It will be appreciated that the fan 132 may also provide cooling to the sensor 112a by blowing air over the sensor 112a. It may be desirable to provide cooling to the sensor(s) 112 because as the sensor(s) 112 may be exposed to high levels of heat emitted by the cooktop 108.

[0079] While the drawings show examples of where the cooktop safety device may be positioned relative to the cooktop, it is to be understood that the cooktop safety device may be otherwise positioned. For example, on a ceiling, towards the center of a hood fan, on a countertop stand, on a wall, within a cavity in the wall, etc. Further, while the drawings show examples of a cooktop safety device having one or two sensors (i.e. , units), it is to be understood that the cooktop safety device may include any number of sensors.

[0080] Reference is next made to FIG. 4, which illustrates another example cooktop surface monitoring unit 402, which includes a controller 420. Cooktop surface monitoring unit 402 also includes a sensor 412, a microphone 424, a communications module 426, an indicator light 428, a speaker 430 and a switch 432, each of which is coupled to the controller 420. Cooktop surface monitoring unit 402 also includes a power source 434 that is coupled to each of elements of cooktop surface monitoring unit 402 that require electrical power (power couplings not shown). [0081] Controller 420 controls the operation of the cooktop surface monitoring unit 402. Controller 420 may be any type of control element such as a microcontroller, microcomputer, field programmable gate array (FPGA) or any other device capable to coupling with and controlling the operations of the system elements coupled to it. In some embodiments, the controller may be including multiple processing and control devices. In some embodiments, the controller may include local components and remote components accessible to the cooktop surface through the communications module 426.

[0082] In operation, cooktop surface monitoring unit 402 will typically be mounted adjacent a cooktop, as illustrated in Figures 1-3 with respect to cooktop surface monitoring unit 102.

[0083] Sensor 412 may be an array sensor such as a thermopile infrared sensor array that provides thermal information relating to the cooktop and to objects, such as cookware and food, above the cooktop. Sensor 412 generates a series of images of a cooktop and transmits image data corresponding to the images to the controller 420. Controller 420 analyzes the incoming image data to identify cooktop events. For example, the controller 420 may analyze the temperatures recorded at different parts of the cooktop, including portions of the cooktop corresponding to heating elements to identify patterns that may correspond to various cooktop events. As another example, the controller 420 may compare the incoming image data to recorded image data (which may include individual images or a time series of images) corresponding to cooktop events or to patterns corresponding to cooktop events to determine that a cooktop event may be underway. The controller may compare individual or a time series of image data to recorded image data to identify a cooktop event. Controller 420 may implement either of these approaches, ora combination of them, to identify cooktop events. In some embodiments, the controller may receive additional data and may also analyze that additional data to identify a cooktop event. For example, the controller may receive audio data as discussed below.

[0084] In some embodiments, the controller may compare incoming image data to a representation of previously obtained image data corresponding cooktop event using a machine learning module. For example, the previous image data may be used to train a machine learning model. Incoming image data may be compared to the machine learning model to identify image data that may correspond to a cooktop event.

[0085] Indicator light 428 may be any type of light emitting device. For example, indicator light be a light bulb, a light emitting diode (LED), a fluorescent lamp, a halogen lamp or any other type of light emitting device.

[0086] When controller 420 identifies a cooktop event, controller 420 may perform a cooktop event response, including indicating the cooktop event in one or more ways. Controller 428 may activate indicator light 428 to indicate that a cooktop event has been identified. In some embodiments, indicator light 428 may be in an unactivated state (i.e. an off or unlit state) when the controller is not indicating a cooktop event. To indicate a cooktop event, the controller may activate the indicator light (ie. put the indicator light in an on or lit state). In some embodiments, the controller may control the indicator lamp to indicate different types or degrees of cooktop events. Indicator lamp 428 may be capable of emitting multiple colors of light. For example, the indicator lamp may be capable of emitting green, yellow and red light to indicate different alert or severity levels. For example, when the controller has not identified a cooktop event, the controller may operate the indicator light to be green, corresponding to a low alert level. When the controller has identified a cooktop event that is imminent or of a relatively less dangerous nature, it may operate the indicator light to be yellow, corresponding to an intermediate alert level. When the controller has identified a cooktop event that is underway, the controller may operate the indicator light to be red corresponding to a high alert level.

[0087] In various embodiments, the indicator light may be an assembly of multiple light emitting devices. For example, the indicator light 428 may be a combination of red, yellow and green LEDs that may be independently activated to indicate different alert levels. In other embodiments the indicator light may include one or more multi-color or tri-color LEDs that may be activated to emit different colors of lights to indicate different alert levels.

[0088] Controller 420 may indicate a cooktop event by activating speaker 430 to emit a warning sound. The speaker may be an unactivated (or silent) state when the controller is not indicating a cooktop event. To indicate a cooktop event, the activate the speaker to make a warning sound. In some embodiments, the controller may activate the speaker to make different warning sounds different types or degrees of cooktop events. For example, the controller may activate the speaker to make a relatively less intrusive sound (such an intermittent sound or a relatively quieter sound) to indicate an intermediate alert level. The controller may activate the speaker to make a relative more intrusive sound (such as a continuous sound or a relatively louder sound) to indicate a high lever alert. In some embodiments, the controller may activate the speaker to enunciate words corresponding to a cooktop event, such as “Warning”, “Alert”, “Emergency”, “Flame Detected on the Cooktop”, “Cooktop is not attended”, etc.

[0089] Controller may indicate a cooktop event by transmitting or pushing a notification to a user’s device. The communication module 426 may include wired or wireless communication modules allowing the controller to transmit a notification to a user’s device 436 through a communication network 434. The communication module 426 may be capable of various types of communication according to various standards, including, for example, one or more of WiFi, Bluetooth Low Energy (BLE), Zigbee, Z-wave, Ethernet, etc. Controller may transmit a notification to the user’s device indicating a type and severity of a cooktop event. For example, an notification may indicate that a low severity event corresponding to a cooktop being unattended for a relatively short time. A notification may indicate a very high severity event corresponding to a flame being detected on the cooktop. A notification may cause one or more of a visual display, an audible sound or a haptic action such as causing a user’s device to vibrate to occur at the user’s device.

[0090] The controller 420 may indicate a cooktop event using one or more of the cooktop event indication systems: a visual indication (using the indicator light 428), an audible indication (using the speaker 430) or a notification transmitted to a user device (using the communication module 426).

[0091 ] Microphone 424 may be operable to monitor sounds in the vicinity of the cooktop surface monitoring unit 402 and transmit corresponding audio data to the controller 420. The controller 420 may use this information in several ways. [0092] For example, the controller 420 may use the audio data to identify a cooktop event. As described above, the controller analyzes image data from the sensor 412 to identify cooktop events. The controller may refine such analysis by analyzing the audio data received from the microphone 424. For example, the controller 420 may compare the audio data to audio signatures accessible to the controller 420. The controller 420 may have access to cooktop event audio signatures corresponding to cooktop events such as a cooktop fire, flames on a cooktop, and oil or milk boil over and other cooktop events. The controller may use the results of a comparison of the incoming audio data to such cooktop event audio signatures to refine an analysis of image data to identify a cooktop event. If the controller’s analysis of the image data indicates that a cooktop event is occurring, the controller may increase its confidence that an indication of a cooktop event should be made of an analysis of the audio data also indicates that a cooktop event is occurring. This may allow the controller to indicate a cooktop event more quickly than if the controller analyzed only image data from the sensor 412. The controller may also use an analysis of the audio data to reduce its confidence that a cooktop event is occurring. For example, the controller may have access to safe activity audio signatures, which correspond to cooking activities that are not considered dangerous. If a comparison of the incoming audio data corresponds to one or more safe activity audio signatures, then the controller may reduce its confidence that a cooktop event is occurring and may accordingly defer an indication of a cooktop event, even though an analysis of image data from the sensor 412 may, by itself, indicate a cooktop event. As with the image data, the controller 420 may compare incoming audio data to cooktop event audio signature or safe cooking activity audio signature using a machine learning approach. Previous audio data corresponding cooktop events or safe cooking activity (or both) may be used to a train a machine learning model. Incoming audio data may be compared to the machine learning model to refine the controller’s identification of cooktop events.

[0093] The controller may also use audio data to modify its operation in response to commands from a user. For example, the controller may identify commands such as “Quiet”, “Silence for 10 Minutes”. The controller may be configured to identify such commands if they are preceded by a wake or activation word such as “Cooktop”. For example, the controller may be configured to respond to an audio command such as “Cooktop, silence for 10 minutes” by not indicating a cooktop event for the next 10 minutes. This may allow a user to carry out a cooking task that might be identified by the controller as a cooktop event without receiving an indication of a cooktop event. For example, a cooking activity such as flambeing requires flames on a cooktop. The user may prefer to flambe their food without receiving a cooktop event indication. As another example, if the processor detects a command such as “Cooktop, Quiet”, the processor may terminate any ongoing indication of a cooktop event. The controller may confirm user commands by activating the speaker to indicate that the controller has detected the command and is taking the commanded action.

[0094] Switch 432 is coupled to controller 420 to allow a user to provide switch inputs. A user may press the switch 432 to provide a switch input. The controller may respond to switch inputs in various ways. For example, the controller may respond to a switch input by turning the cooktop surface monitoring device 402 on or off. As an other example, the controller may respond to a switch input by terminating any indication of an ongoing of a cooktop event.

[0095] Some of the elements illustrated in FIG. 4 are optional and may not be present in various embodiments. For example, some embodiments may not include a switch and may be powered on whenever the device is receiving power. In some embodiments, a microphone may not be present. In some embodiments, an indicator light may not present. In some embodiments, a speaker may not be present. In some embodiments, a communication module may not be present. In any particular embodiment of a cooktop surface monitoring unit 402, at least one method of indicating a cooktop event to a user will be provided.

[0096] As noted above, a cooktop surface monitoring unit 402 may be provided alone, with a cooktop power monitoring unit or with additional sensor units or with a combination of such units. When provided with a cooktop power monitoring unit, the cooktop surface monitoring may identify cooktop events using electrical power draw information from cooktop power monitoring unit. The controller 420 may also operate the cooktop power monitoring unit to cut power to the cooktop. [0097] Cooktop surface monitoring unit 402 is powered from power source 434. The power source provides power to each of the other elements of the cooktop surface monitoring unit 402 that require power. In various embodiments, the power source 434 may be a plug or port that is coupled to a battery, a power supply that is in turn connected to a utility electrical power supply or another power source. The power source may include a transformer or other power conversion or conditioning circuit to provide a power signal suitable for powering the components of the cooktop surface monitoring unit 402.

[0098] Reference is next made to FIGS. 5-8, which illustrates another example cooktop surface monitoring unit 502. Various elements of cooktop surface monitoring system 502 correspond in function to elements of cooktop surface monitoring system 402 and are generally identified with corresponding reference numerals. Cooktop surface monitoring unit 502 includes a housing 540 and an electronics assembly 546. Housing 540 includes a front cover 542 and a back cover 544. Electronics assembly 546 includes a circuit board 548 and a sensor 512, a controller 520, a microphone 524, a communications module 526, an indicator light 528 comprising a plurality of tri-color LEDs 528, a speaker 530, a pair of parallel push button switches 532 and a power source 534. Controller 520 is a microcontroller provided in the form of an integrated circuit, which also includes communications module 526. The other elements of cooktop surface monitoring unit 502 are mounted on a circuit board 550 and are coupled to one another as illustrated in relation to cooktop surface monitoring unit 402 in FIG. 4 through the circuit board. Speaker 530 is mounted to the circuit board at a pair of speaker mounting pads 529.

[0099] In this embodiment, power source 532 is a port compliant with a USB- C standard. The power input port may be used for both power input and for wired communication. Power may be supplied to the power port 534 from a power adapter coupled to a utility power supply. The wired communication functionality of the power input port is also part of the communications module 526.

[00100] The electronics assembly is mounted with the housing 540. The electronics assembly is mounted to a mounting plate 552 at a set of mounting bosses 553 which contains apertures 562, 564, 566 aligned with the sensor 522, microphone 524 and the speaker 530. The mounting plate is in turn mounted to the front cover, fixedly mounting the electronics assembly to the front cover 542. The front cover includes an aperture array 556 aligned respectively with the microphone 524 and speaker 530 to allow sound to pass into and out of the housing 540 to the microphone and speaker. The front cover also includes an IR pass- through element 571 aligned with the sensor which, in this example embodiment, is an I R thermal array sensor. When assembled, the IR pass-through element may be flush with the external front surface of the front cover 542, thereby allowing the front surface to be easily wiped down to keep the IR pass-through element clean and thereby reducing the effect of any grease buildup on the operation of the sensor 512.

[00101] Cooktop surface monitoring unit 502 also includes a light transmitter I push bar 558 mounted in the front cover 542 and aligned with the LEDs 528 and with the switches 532. The light transmitter I push bar 558 is formed of a light transmitting and diffusing material to diffuse light emitted by the LEDs such that indications of cooktop events indicated by light emitted from the LEDs is visible outside of the housing 540 through the light transmitter I push bar 558. The light transmitter/ push bar 558 is aligned with the switches 532 such that a user pressing the light transmitter I push bar 558 will press at least one of the parallel switches to provide a switch input to the controller 520. The combined light transmitter I push bar 558 provides a visible indicator of a cooktop event which a user may easily push from either the right or left side (to activate at least one of the switches 532) to provide a switch input. A user may thus easily silence an audible indication of a cooktop event by directly pressing the visual indicator of the cooktop event.

[00102] The front cover 542 and 544 are illustrated in expanded form in FIG. 8. In use, the front cover 542 and 544 will be assembled together to form the housing 540 of the cooktop surface monitoring unit 502. The cooktop surface monitoring unit 502 may be mounted on a wall 506 adjacent to a cooktop 508 by mounting the back cover on the wall. Optionally, an angled wall plate 572 may be used to tilt the cooktop surface monitoring unit 502 to align the field of view of the sensor 512 with the surface of the cooktop 508. In the illustrated example, the back cover may be attached to the wall plate using finger hooks 574 and screws 576. [00103] Referring to FIG. 9, the angled wall plate may be used to tilt the field of view of the sensor 512 outwards as illustrated at 580 or inwards as illustrated at 582. The allows the cooktop surface monitoring unit 502 to be mounted at various heights adjacent to a cooktop 508 with the field of view of the sensor 512 aligned with the surface of the cooktop 508, as illustrated by lines 584, 586.

[00104] In other installations, the cooktop surface monitoring unit 502 may be assembled in a different shaped housing and may be installed on a range hood as illustrated in FIG. 2 or in another position or manner such that the cooktop surface is within the field of view of the sensor 512. In some embodiments, the cooktop surfaced monitoring unit 502 may be integrated within the range hood.

[00105] In operation, cooktop surface monitoring unit 502 operates as described above in relation to cooktop monitoring unit 402 to monitor a cooktop and to provide indications of cooktop events. Cooktop surface monitoring unit 502 may be provided with or without a cooktop power monitoring unit.

[00106] Various examples of uses of cooktop safety devices and methods for detecting cooktop events are described below. It is to be understood that the examples that follow are not meant to be limiting and a cooktop safety device may have the sensor arrangements and data analysis techniques of one or more of the examples described below. Further, it is to be understood that the examples described below are not meant to be limiting of the types of cooktop events that may be detected using the type and arrangement of sensors described herein.

Flame Detection

[00107] The cooktop safety device may comprise a sensor for monitoring a cooktop surface for the presence of flames. It may be desirable to detect the presence of flames on the cooktop because a burning object (e.g., food) on the cooktop may be unsafe. If left unattended, the burning object could cause significant damage to the cooktop and/or the surrounding environment.

[00108] It has been determined that flame detection may be a useful indication that a cooktop event is occurring as an alternative to or in combination with high temperature heating element detection. There are many common cooking techniques that require heating elements to be set to high temperatures that may be performed safely. Accordingly, in many cases a high temperature heating element is not truly a cooktop event (i.e., not unsafe use of the cooktop). In contrast, there are few cooking techniques that intentionally produce flames. Therefore, flame detection may, in some situations, be a more accurate indication of a cooktop event.

[00109] In one embodiment, a cooktop surface monitoring unit may comprise a camera for taking images of the cooktop surface, in addition or as an alternative to the sensors described above in relation to units 402 and 502. The camera may be any camera known in the art suitable for taking an image of a cooktop surface. The camera may continuously take images of the cooktop surface or may periodically take images of the cooktop surface.

[00110] The images of the cooktop surface captured by the camera may be analyzed by the cooktop surface monitoring unit controller. Using image recognition software, the processor may determine whether flames are present in the image or not. If flames are detected in the image, the processor may register the occurrence of a cooktop event and perform a cooktop event response.

[00111] Optionally, the camera may have a field of view which includes the cooktop and at least a portion of the space in front of the cooktop. Using image recognition software, the processor may determine whether an operator is within the space in front of the cooktop. If the image recognition software recognizes the presence of flames and an operator in the image taken by the camera, the a cooktop surface monitoring unit may not identify a cooktop event as the presence of the operator may indicate that the cooktop is being used safely. It will be appreciated that multiple images over a period of time may be captured. If the image recognition software detects the presence of flames and an operator in successive images over a predetermined period of time, regardless of the presence of the operator, the cooktop safety device may identify a cooktop event and may perform a cooktop event response.

[00112] In other embodiments, the cooktop safety device may comprise a thermopile infrared array, as described above in relation to units 402 and 502. It will be appreciated that the thermopile infrared array may detect the intensity of narrowband infrared emissions from liquid or solid objects that radiate heat. Using a blackbody radiation model, the approximate temperature of the liquid or solid object may be estimated. The approximate temperature of the liquid or solid object may be used to detect the temperature of the heating element, cookware, and/or food item. The temperature of the heating element, cookware, and/or food item may indicate that a cooktop event is occurring, depending on the cooking process underway.

[00113] It will be appreciated that because flames are not solid nor liquid, thermopile infrared arrays cannot detect the presence of a flame directly. However, it has been determined that if the thermopile infrared array is positioned to be aligned with at least a portion of the burning object and the flames being emitted by the burning object in view, the thermopile infrared array can infer the presence of flames by the presence of perturbations in the temperature estimates of the burning object in a series of temperature estimates. More specifically, it has been determined that flames produced by a burning object may create fluctuating pressure and/or density fields in the air near the flame. When the thermopile infrared array is positioned such that infrared radiation received by the thermopile infrared array passes through the air near the flame having fluctuating pressure and/or density fields therein, the output (i.e., data) from the thermopile infrared array may exhibit temporal perturbations.

[00114] FIG. 10 shows an example of a temperature vs. time output from a thermopile infrared array positioned to be aligned with a burning object and the flames to be produced by the burning object. In the graph, it can be seen that at time t = -5 seconds, the cooktop is turned on. From time t = -5 seconds to time t = ~45 seconds there is a relatively constant rise in temperature as the cooktop, cookware, and food object heat up. As shown, there are little temporal perturbations in this heating phase. At time t = ~45 seconds, the food item catches fire. From time t = ~45 second to time t = -135 seconds the temperature continues to rise, but in a detectable fluctuating manner. As described above, these variations (i.e., perturbations) in the temperature vs. time data are caused by fluctuating pressure and/or density fields produced by the flame in the air that interfere with the infrared radiation received by the thermopile infrared array. [00115] The cooktop safety device processor may be configured to recognize temporal perturbations in temperature vs. time data collected by the thermopile infrared array. When the processor detects temporal perturbations in temperature vs. time data collected by the thermopile infrared array it may predict the presence of flames and may identify the situation as a cooktop event.

[00116] Optionally, the thermopile infrared array may have a field of view which includes the cooktop and at least a portion of the space in front of the cooktop. In this embodiment, the processor may be configured to recognize the presence of an operator in the space in front of the cooktop. If the processor recognizes the presence of flames and an operator in the data collected by the thermopile infrared array, the cooktop safety device may not register the occurrence of a cooktop event as the presence of the operator may indicate that the cooktop is being used safely. It will be appreciated that multiple “thermal images” over a period of time may be captured of the cooktop and the space in front of the cooktop. If the processor detects the presence of flames and an operator in successive thermal images over a period of time, regardless of the presence of the operator, the cooktop safety device may register the occurrence of a cooktop event.

Cooktop Heating Element Temperature Detection

[00117] As described above, while the temperature of a cooktop heating element may not always be an accurate representation of whether a cooktop event is occurring, an estimate of the heating element temperature may still be valuable when monitoring for cooktop events. For example, overly high heating element temperatures may be indicative of an uncovered heating element that has been left on. As a second example, raising heating element temperatures may be a warning that an object may catch on fire. Accordingly, a cooktop safety device may have flame detection sensors that only collect data when a heating element temperature is above a predetermined threshold and/or the processor may only analyze the data for the presence of flames when a heating element temperature is above the predetermined threshold.

[00118] Any sensor suitable for detecting the temperature of a heating element may be used. For example, a thermopile infrared array may be used to estimate heating element temperature. As another example, a cooktop power monitoring unit may be used to estimate the temperature of an electric cooktop heating element.

[00119] Supply of current to a heating element may typically be regulated by an on-off duty cycle of applied voltage controlled by a thermally-responsive switch. That is, for example, if the cooktop heating element is set to “medium”, the thermally-response switch may stop current flow to the heating element once the heating element reaches, for example, 120 degrees Celsius, and reinitiate current flow to the heating element if the heating element drops below 110 degrees Celsius. Accordingly, the heating element may be kept at an average of 115 degrees Celsius. It will be appreciated that the switching setpoint of the thermally- responsive switch may be controlled by, for example, a user of the cooktop turning a knob.

[00120] It has been determined that a measurement of the current supplied to a cooktop heating element may be used to estimate the temperature of that heating element. Specifically, it has been determined that the conducting material typically used in cooktop heating elements may exhibit a temperature-dependent resistance characteristic such that increasing temperature results in increased resistance. Therefore, fora fixed voltage supply, a heating element starting at room temperature may draw more current than the same heating element after being raised to an elevated operating temperature. Accordingly, measurements of the current to the heating element may be used to estimate the temperature of that heating element.

Cooktop Heating Element Coverage Detection

[00121] It will be appreciated that cooking heating elements may have a greater surface area than the cookware placed thereon. Accordingly, a portion of the heating element may be exposed during regular, safe, cooking activities. When monitoring temperatures of the cooktop, a thermal sensor may detect a relatively high temperature at the uncovered portion of the heating element and a relatively low temperature at the covered portion (this is a consequence of normal thermodynamic heat flow from a heating element to environment vs. the cookware). It has been found that known cooktop safety devices do not recognize that a heating element may be partially covered and can trigger an unsafe cooking alarm due to measuring the relatively high temperature of the exposed portion of the heating element even though this is not an unsafe cooking event. Further, it has been found that the relatively high temperature of the exposed portion of the heating element may skew the data collected when monitoring cooktop temperatures when predicting fire risk.

[00122] Accordingly, the cooktop safety device processor may be configured to recognize a partially exposed heating element and to not identify the situation as a cooktop event, and therefore not perform a cooktop event response in view of data collected from the partially exposed heating element.

[00123] In a first example, a camera may take images of the cooktop and using image recognition software, the processor may determine whether a heating element is partially exposed.

[00124] In a second example, the processor may recognize a partially exposed cooktop heating element based on temperature data collected by a thermal sensor. More specifically, a thermopile infrared array may generate a heat map of the of the cooktop. Based on a geometric analysis of the heat map, it may be determined that a heating element is partially uncovered. For example, if the heat map shows a relatively high temperature crescent partially surrounding a relatively low temperature oval/circle, it may be determined that a heating element is partially uncovered.

[00125] Alternatively, or in addition, a temperature vs. time analysis of portions of the cooktop may be performed. It has been found that uncovered portions of a heating element will display a temporal waveform on a temperature vs. time graph that is different than that of a covered portion of a heating element. Specifically, an uncovered heating element and/or portion of a heating element can be recognized by sharp rises and falls in temperature whereas a covered heating element and/or portion of a heating element will have a relatively gentle increase and/or decrease in temperature.

[00126] Alternatively, or in addition, the processor may use known locations of the heating elements on the cooktop when determining whether a heating element is partially or fully covered. The location of the heating elements may be determined by the processor during a calibration session (e.g., once the cooktop safety device is installed, the user may turn on all heating elements for a period of time while uncovered so the cooktop safety device can generate a layout of the cooktop). Alternatively, data relating to the make and model of the cooktop may be uploaded to the cooktop safety device by a user during an installation session.

Unattended Cooktop Detection

[00127] It will be appreciated that leaving a cooktop that is powered on unattended for a period of time may be considered a cooktop event (i.e., may be considered unsafe). Accordingly, the a cooktop surface monitoring unit may be configured to recognize when the powered on cooktop has been left unattended.

[00128] In a first example, a cooktop surface monitoring unit may include a motion sensor for detecting movement in the area directly in front of the cooktop. Motion in the area in front of the cooktop may be indicative of a person monitoring the cooktop.

[00129] In a second example, a cooktop surface monitoring unit may include a thermopile infrared array with a field of vision that includes the cooktop and the area in front of the cooktop. If a heat source is detected in the area in front of the cooktop, it may be indicative of a person monitoring the cooktop. In some examples the thermopile infrared array may produce a thermal image of the cooktop and the area in front of the cooktop with a resolution great enough for the processor to identify whether an adult, child, or animal is in the area in front of the cooktop. It will be appreciated that if the processor determines that a child is in front of the cooktop, a cooktop event may still be identified, even though a human is present.

[00130] Optionally, the cooktop safety device will measure the amount of time that has passed since the cooktop has last been attended. If the amount of time exceeds a predetermined threshold, a cooktop event is identified and the cooktop safety device may perform a cooktop event response. The cooktop event response may be pushing a notification on a mobile device to remind the user to attend to the cooktop. In some embodiments, the cooktop safety device may activate an indicator light (such as indicator light 428) to indicate that the threshold time period has elapsed without the cooktop being attended. In some embodiments, if a relatively shorter time threshold has elapsed with an unattended cooktop, the controller may activate a yellow light or an intermediate alert sound, or transmit a notification to a mobile device indicating an intermediate alert level.

[00131] In some examples, the cooktop safety device may be able to distinguish between two or more frequent users of the cooktop. In this example, the notification may be pushed to the mobile device of the last user detected to have used the cooktop. Any means suitable for distinguishing one frequent user from another may be used. For example, the cooktop safety device may distinguish frequent users of the cooktop from each other by predetermined thermal images of those users captured during a calibration session or based on voices identified in audio data from a microphone in a cooktop surface monitoring unit.

Child Detection

[00132] As described above, the cooktop safety device may be configured to detect the presence of a child in front of the cooktop using a thermopile infrared array. In some examples, when the cooktop safety device detects (a) the presence of a child in front of the cooktop and (b) a change in temperature at the surface of the cooktop, it may be inferred from this data that the child has turned on a heating element or has turned up the heating element. In this scenario, the cooktop safety device may identify a cooktop event and perform a cooktop event response as a child turning on the cooktop or turning up the temperature of a heating element may be unsafe.

Unattended Oven Detection

[00133] It will be appreciated that cooktops may often be part of a range which includes the cooktop and an oven. When a cooktop safety device is monitoring the cooktop of a range, characteristics of the oven may be inferred from data collected by the cooktop safety device.

[00134] For example, the cooktop safety device may include a cooktop surface monitoring unit for detecting temperatures of the cooktop surface and a range power monitoring unit (it will be appreciated that power from a single wall outlet may be provided to the cooktop and the oven). When the range power monitoring unit detects a power draw and the cooktop surface monitoring unit does not detect heating of a heating element, it may be inferred that the power is being supplied to the oven.

[00135] An approximate oven temperature may be determined by measuring the current being supplied to the range as a correlation between oven temperature and supplied current has been determined.

[00136] Further, it has been determined that there is a correlation between cooking temperature and cooking time. That is, food items cooked at a relatively low temperature may typically be in the oven for a relatively long period of time whereas a food items cooked at a relatively high temperature may typically be in the oven for a relatively short period of time. Accordingly, if the cooktop surface monitoring unit detects a high oven temperature for a long period of time, the cooktop safety device may identify a cooktop event and perform a cooktop event response (i.e. , an oven event response which may include pushing a notification to a mobile device, sounding an alarm, cutting power to the range, etc.).

Oil vs. Water Detection

[00137] It will be appreciated that fire suppression techniques for overheating cookware and/or cookware having burning food items therein may vary if the cookware contains a volume of water versus a volume of oil. Accordingly, it may be desirable for the cooktop safety device to be able to distinguish between cookware containing a volume of water and cookware containing a volume of oil.

[00138] It has been determined that water has a characteristic temperature vs. time curve when the heating element heating the cookware is supplied with a constant power input. More specifically, it has been determined that water has a characteristic temperature vs. time curve that plateaus once the water has reached 100 degrees Celsius. Oil, on the other hand, has been found to have a characteristic temperature vs. time curve which continues to increase well beyond 100 degrees Celsius.

[00139] Accordingly, when provided with temperature data of cookware holding a volume of liquid, the cooktop safety device may be able to recognize whether the cookware is holding a volume of liquid or if the cookware is holding a volume of oil. More specifically, the processor may recognize that the cookware contains a volume of water or oil (as opposed to a food item such as chicken) based matching received temperature data over time to the characteristic temperature vs. time curves for water and oil. The processor may then distinguish between water and oil based on whether the temperature continues to rise above 100 degrees Celsius or not.

[00140] It will be appreciated that any sensor suitable for estimating the temperature of the cookware and its contents may be used. For example, a thermopile infrared array may be used.

Safety Risk Indexing

[00141] As discussed above, monitoring a cooktop and/or the surrounding area for cooktop events requires the collection and analysis of a large amount of data. In some embodiments, this data may be used to classify the individual associated with the cooktop safety device on a safety risk index (it is understood that multiple individuals may frequently use a cooktop and accordingly they may share a safety risk index classification). The safety risk index may classify a user as very likely to cause a cooktop event, very unlikely to cause a cooktop event, or somewhere therebetween.

[00142] To classify a user on the safety risk index the following factors, optionally among others, may be used: (a) average date, time, and/or duration of cooktop operation; (b) building geographic location (e.g., distance from firehall); (c) building type (single family home, multi-dwelling unit, restaurant, etc.) (d) if applicable, unit location within the building; (e) type of cooktop (e.g., gas, electric, induction); (f) age of cooktop; (g) frequency of detected cooktop events; and/or (h) type of cooktop event.

[00143] An individual’s safety risk index classification may be updated continuously or periodically (e.g., based on monthly trailing averages to provide trending information).

[00144] An individual’s safety risk index classification may be provided to (a) the individual; (b) if applicable, a landlord of the individual; and/or (c) and insurance provider of the individual. Along with the individual’s safety risk index classification, an individual may be provided with recommendations on how to improve their classification on the safety risk index.

Smart Home Integration

[00145] The cooktop safety device described herein may integrate into a preexisting smart home system (i.e. , may connect to a smart home hub) and/or may be configured as a smart home hub.

[00146] As a component with a smart home system, the cooktop safety device may communicate with components of the smart home system to improve the functionality of the cooktop safety device.

[00147] For example, a smart home system may include fire alarms and the cooktop safety device. In this example, when a cooktop event is detected, the cooktop safety device may signal the fire alarms to sound.

[00148] Optionally, to classify a user on the safety risk index, as described above, data collected by other components in the smart home system may be used. For example, any one of, but not limited to, the following events may be detectable by a smart home system component, and the detection and/or frequency of such an event may impact the user’s classification on the safety risk index: (a) smoke alarm event; (b) electrical ground faults and circuit breaker events; (c) supply plumbing leak events; (d) drain plumbing leak events; (e) intrusion alarm events; and (f) glass-break events.

[00149] It is to be understood that a smart home system may include components that are within different units within a multiple dwelling complex. Accordingly, the events detected in a first unit may be used to classify a user on the safety risk index of a second unit. For example, a first user’s classification on their safety risk index may be affected if a second user in a neighboring unit is prone to generating unsafe events. Neighboring units may share a wall, share a floor, be on an adjacent floor, or may be in the same multiple dwelling complex.

[00150] The safety risk index classification of tenants in a multiple dwelling complex may be provided to the multiple dwelling complex property owner, the multiple dwelling complex property manager, and/or to an insurer to allow them to assess risks associated with the occupants. Optionally, a classification on the safety risk index may be provided for the multiple dwelling complex as a whole (i.e. , an average of the individual safety risk index classifications of occupants).

While the above description provides examples of various embodiments, it will be appreciated that some features and/or functions of the described embodiments are susceptible to modification without departing from the spirit and principles of operation of the described embodiments. Accordingly, what has been described above has been intended to be illustrative of the invention and non-limiting and it will be understood by persons skilled in the art that other variants and modifications may be made without departing from the scope of the invention as defined in the claims appended hereto.