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US 11,622,420 B2Granted
Electric grill with current protection circuitry
AssigneeWeber-Stephen Products LLC
InventorsEric Knappenberger, Julio C. Zuleta, Matthew Lerch, Jeffery C. Emmerich
Life of this patent
Estimating the term…
Abstract
Provided is an apparatus and method for protecting against unsafe electric current conditions. A protections circuit may be used in a device, such as an electric grill, that has one or more electric loads, such as heating elements. The protection circuit may protect against various failure scenarios, including, without limitation, instances of ground fault, over current, driver failure, and failure of a microprocessor. In response to a failure, the protection circuit may trip a latch relay or disable a triac driver to stop current from flowing.
Claims16
An electric grill, comprising:
- a heating element connected to a voltage line through a triac, and further connected to a neutral line;
- a knob for selecting an operating mode of the heating element;
- a trip controller in communication with a latch, the latch being connected between the heating element and the voltage line;
- a current sensor for measuring current delivered to the heating element;
- a memory;
- a display to present the selected operating mode of the heating element;
- and
- a microprocessor in operable communication with the knob, the trip controller, and the current sensor, wherein the microprocessor is to:
- receive a current measurement from the current sensor;
- access the memory to receive an expected current associated with the selected operating mode;
- select a current threshold based on the expected current associated with the selected operating mode, the current threshold being less than the expected current;
- cause the trip controller to disable the latch in response to the current reading from the current sensor being less than the current threshold;
- and
- cause, in response to the disabling of the latch, the display to present an alert to indicate that the latch has been disabled.
11 more elements
An electric circuit for operating and protecting an electric grill, comprising:
- a heating element in communication with a user input device for selecting a high, medium, or low operating mode of the heating element;
- a display to display the selected operating mode;
- a latch to disable the flow of current to the heating element;
- a current sensor to measure a current delivered to the heating element;
- and
- a microprocessor connected to a triac, the triac connected between a voltage line and the heating element such that the microprocessor is to control the heating element by activating the triac;
- wherein the microprocessor is further to:
- receive the measured current from the current sensor;
- access the selected high, medium, or low operating mode from the user input device;
- retrieve an expected current associated with the selected high, medium, or low operating mode from a memory;
- select a current threshold based on the expected current associated with the selected high, medium, or low operating mode, the current threshold being less than the expected current;
- cause the latch to become disabled in response to the measured current being less than the current threshold;
- and
- cause, in response to the current being less than the current threshold, the display to present an alert to indicate that the heating element has been disabled.
11 more elements
An electric grill, comprising:
- a housing having one or more user inputs for selecting a high, medium, or low operating mode of a heating element, and a display to display the selected operating mode;
- an electric cord connected to a voltage line and a neutral line, the heating element being connected to a triac and further connected to the voltage line and neutral line;
- at least one latch relay connected between the heating element and the voltage line, the latch relay to selectively disable a flow of current to the heating element;
- a microprocessor connected to a triac driver, the triac driver being in communication with the triac, wherein the microprocessor is to activate the triac driver to deliver a current associated with the selected operating mode;
- and
- a current sensor to measure current passing through the triac, the current sensor to provide a measured current to the microprocessor;
- and
- wherein the microprocessor is further to:
- access the measured current from the current sensor;
- access a memory to retrieve an expected current threshold associated with the selected high, medium, or low operating mode of the heating element, the expected current threshold being less than an expected current associated with the selected high, medium, or low operating mode of the heating element;
- compare the measured current with the expected current threshold for the selected high, medium, or low operating mode;
- disable the flow of current to the heating element in response to a measured current that is less than the expected current threshold;
- and
- cause the display to present an alert, the alert to indicate that the flow of current has been disabled.
11 more elements
Dependencies are inferred from the claim text.