US Patent 7378617 Heating systems and methods for a cooking appliance

A heating system for a cooking appliance includes a first upper heating element and a second upper heating element positioned within a cooking cavity defined by a cabinet of the cooking appliance. The cooking cavity is configured to support a food item therein during a cooking process. Each of the first upper heating element and the second upper heating element is positioned with respect to an upper portion of the food item. A lower heating element is positioned within the cooking cavity. The lower heating element is positioned with respect to a bottom portion of the food item. A controller is operatively coupled to the lower heating element and the first and second upper heating elements. The controller is configured to asynchronously energize the first upper heating element and the second upper heating element to heat the upper portion of the food item.