Patent ID: 8025743

Claim:
A dishwashing appliance, comprising: a tub portion defining a forward access opening and having a lower end; a sump assembly disposed about the lower end of the tub portion for receiving the washing fluid therein; a door assembly pivotably engaged with the tub portion about the lower end, and movable between an open position and a closed position, the door assembly being configured to cooperate with the tub portion to cover the forward access opening in the closed position; a lower spray arm rotatable about an axis and disposed about the lower end of the tub portion, the lower spray arm being configured to spray washing fluid from the sump assembly toward the tub portion, wherein the lower spray arm includes a hub portion with at least one spoke portion extending therefrom, the hub portion being operably engaged with an axial member associated with the sump assembly and defining the axis; a control device configured to actuate the lower spray arm to spray the washing fluid; and a detection device in communication with the control device and configured to interact with the lower spray arm, the detection device being further configured to direct the control device to prevent actuation of the lower spray arm in response to the detection device detecting a force applied to the lower spray arm with respect to the axis, with the door assembly in the closed position prior to spraying washing fluid through the lower spray arm or initiating a wash cycle, wherein the detection device comprises a force-sensitive sensor operably engaged between the hub portion and the axial member, and wherein the force-sensitive sensor is configured to determine an axial force applied to the lower spray arm toward the sump assembly.