Patent ID: 7740711

Claim:
A parts washer, comprising: a reservoir for holding a cleaning fluid at a level; a receptacle connected on the reservoir; a drain defined in the receptacle for fluid communication between the receptacle and the reservoir; a frame connected to the reservoir; a guard connected to the frame including a front wall, a back wall, and a lower plate; a pump connected to the lower plate to thereby define a plenum volume between and among the pump, the front wall, the back wall, and the lower plate and to a control module; a pump inlet in direct communication with the plenum volume so that the pump when activated by the control module moves the cleaning liquid from the plenum volume to the receptacle at a flow rate; a heating element disposed within the reservoir and connected to the frame for adjusting a temperature of the cleaning fluid; a liquid level detector assembly disposed within the reservoir and having an upper end connected to the control module, a lower end disposed adjacent the pump, an intermediate junction disposed between the upper end and the lower end, a first sensor connected to the intermediate junction that generates a first signal representative of a first temperature of the cleaning fluid when the level of the cleaning fluid is at or above the first sensor and a second sensor connected to the lower end that generates a second signal representative of a second temperature of the cleaning fluid when the level of the cleaning fluid is at or above the second sensor; and the control module connected to the frame, the first sensor for receiving and monitoring the first signal generated by the first sensor and the second sensor for receiving and monitoring the second signal generated by the second sensor; wherein the control module includes a processing unit and a memory that stores programming instructions, that when read by the processing unit causes the control module to function to determine a position of the level by comparing the first signal to a first set point and the second signal to a second set point.