Detection of damaged IR sensor array
A cooktop appliance includes a cooking panel comprising a heating zone, an infrared (IR) sensor array positioned below the heating zone, the IR sensor array comprising a shielded IR sensor and an IR source, and a controller operatively coupled to the shielded IR sensor and the IR source. The controller is configured to receive a first signal from the shielded IR sensor, energize the IR source to illuminate a pan in the heating zone, receive a second signal from the shielded IR sensor, identify a fault in the IR sensor array based on a comparison between the first signal and the second signal, and generate a fault signal in response to identifying the fault in the IR sensor array.
1 . A cooktop appliance defining a vertical direction, a lateral direction, and a transverse direction, each of which is mutually perpendicular, the cooktop appliance comprising:
a cooking panel comprising a heating zone;
an infrared (IR) sensor array positioned below the heating zone, the IR sensor array comprising a shielded IR sensor and an IR source;
a heating element positioned between the cooking panel and the IR sensor array, wherein the shielded IR sensor and the IR source are aligned with a passage through the heating element and positioned with a field of view of the pan in the heating zone; and
a controller operatively coupled to the shielded IR sensor and the IR source, the controller configured to:
receive a first signal from the shielded IR sensor;
energize the IR source to illuminate a pan in the heating zone;
receive a second signal from the shielded IR sensor;
identify a fault in the IR sensor array based on a comparison between the first signal and the second signal; and
generate a fault signal in response to identifying the fault in the IR sensor array.
2 . The cooktop appliance of claim 1 , wherein identifying the fault in the IR sensor array based on the comparison between the first signal and the second signal comprises:
computing a signal difference between the first signal and the second signal; and
determining that the signal difference is greater than a predetermined value.
3 . The cooktop appliance of claim 2 , wherein the signal difference is an absolute value of a difference between the first signal and the second signal or a ratio of the first signal and the second signal.
4 . The cooktop appliance of claim 1 , wherein:
the first signal is a response to a temperature of the IR sensor array.
5 . The cooktop appliance of claim 1 , wherein the second signal is a response to IR emitted by the IR source that is reflected and a temperature of the IR sensor array.
6 . The cooktop appliance of claim 1 , wherein the shielded IR sensor is shielded from the IR source.
7 . The cooktop appliance of claim 1 , wherein the first signal and the second signal are received within a predetermined time period.
8 . The cooktop appliance of claim 1 , further comprising a closed-loop heating feature and a user interface, wherein the generated fault signal suspends the closed-loop heating feature.
9 . The cooktop appliance of claim 1 , further comprising a user interface, wherein the generated fault signal causes a display of an error signal on the user interface.
10 . The cooktop appliance of claim 9 , wherein the error signal indicates a damaged IR sensor array.
11 . A method of determining a damaged IR sensor array in a cooktop appliance, the cooktop appliance comprising a cooking panel comprising a heating zone, an IR sensor array comprising a shielded IR sensor, an IR source, and a heating element positioned between the cooking panel and the IR sensor array, wherein the shielded IR sensor and the IR source are aligned with a passage through the heating element and positioned with a field of view of the pan in the heating zone, the method comprising:
receiving a first signal from the shielded IR sensor;
activating the IR source to illuminate a pan in the heating zone;
receiving a second signal from the shielded IR sensor;
identifying a fault in the IR sensor array based on a comparison between the first signal and the second signal; and
generating a fault signal in response to identifying the fault in the IR sensor array.
12 . The method of claim 11 , wherein identifying the fault in the IR sensor array based on the comparison between the first signal and the second signal comprises:
computing a signal difference between the first signal and the second signal; and
determining that the signal difference is greater than a predetermined value.
13 . The method of claim 12 , wherein computing the signal difference comprises performing an absolute value function on a difference between the first signal and the second signal.
14 . The method of claim 11 , wherein the first signal is a difference in resistance across the shielded IR sensor.
15 . The method of claim 11 , wherein the second signal is a difference in resistance across the shielded IR sensor.
16 . The method of claim 11 , wherein the shielded IR sensor is shielded from direct IR emitted from the IR source.
17 . The method of claim 11 , wherein receiving the first signal and the second signal occurs within a predetermined time period.
18 . The method of claim 11 , wherein the cooktop appliance further comprises a closed-loop heating feature and a user interface and the method further comprises:
suspending the closed-loop heating feature; and
displaying an error message on the user interface, the error message corresponding to a damaged IR sensor array.