Patent ID: 6360956
Filing Date: 2002-03-26
Classification: G05D,Y10T

Abstract:
A temperature-actuated mixing valve for controlling outlet temperature in a fluid flow system including a valve housing having first and second fluid supply inlets for introducing first and second respective supply fluids and a fluid outlet for dispensing a fluid at a predetermined outflow temperature, said mixing valve including a shuttle assembly positioned in said housing, said shuttle assembly comprising:(a) a valve member mounted for movement within said housing responsive to the temperature of the supply fluids to vary the mixture ratio of the first and second supply fluids as required to dispense fluid at the predetermined outflow temperature; (b) a shuttle member positioned within said valve member and moveable as a unit therewith within a predetermined range of motion responsive to supply fluid temperature variation, said shuttle member including an elongate grip pad for permitting the shuttle member to be manually removed from the valve housing without the need for tools; (c) a thermal actuator of the type which converts thermal energy into mechanical movement by movement of a piston, a first end of said thermal element engaging said movable shuttle member and an opposing second end engaging a stationary portion of said housing whereby movement of the piston of the thermal actuator produces corresponding movement of the valve member; and (d) an overtravel spring captured in a compressed condition between said valve member and said shuttle member for maintaining the shuttle member and the valve member in a stationary condition relative to each other within the predetermined range of motion of the valve member and for permitting movement of the shuttle member relative to the valve member sufficient to accommodate movement of the piston of the thermal actuator when the valve member has reached its limit of travel without accommodating the full extent of movement of the piston of the thermal actuator.