Patent Number: 6,305,610

Title: Automatic fluid temperature controller and washing machine incorporating same

Abstract: A water temperature control circuit for a washing machine includes window detector and dual water valve drivers to modulate the hot and cold water valves to maintain the water temperature at a desired level. A temperature selector switch provides hot, regulated hot, warm, regulated warm, and cold temperature settings for the washing machine. During regulated temperature operation the window detector modulates one of the water valves to maintain the water temperature within a narrow temperature band. The window comparator includes two comparators that receive a common temperature input from a temperature sensing element. As such, no shunt resistor is required for one or the other comparators, thus improving accuracy. The control circuit operates open loop with respect to the hot and cold water valves that it controls, utilizing instead only the temperature input for controlling the proper water valve when enabled.

Inventors: Estes; Bay E. (Palatine, IL)

Assignee: Ranco Incorporated of Delaware

International Classification: D06F 33/02 (20060101); G05D 23/13 (20060101); G05D 23/01 (20060101); D06F 033/00 (); G05D 023/12 ()

Expiration Date: 10/23/2018