Pressure balanced mixing valve

A mixing valve comprising:

• a housing having a side wall and a bottom wall defining a cavity, said bottom wall having first and second supply ports and an outlet port;
• a housing cap removably mounted on said housing;
• a valve plate having a first outlet aperture and a second outlet aperture rotatably mounted in said housing cap;
• a cartridge non-rotatably disposed in said cavity intermediate said bottom wall and said valve plate;
• said cartridge having a second chamber therein, first inlet passageway upstream of said chamber in communication at its downstream end with said chamber and at its upstream end with said first supply port, second inlet passageway upstream of said chamber in communication at its downstream end with said chamber and at its upstream end with said second supply port, first outlet passageway downstream of said chamber in communication at its upstream end with said chamber and at its downstream end with said valve plate, and second outlet passageway downstream of said chamber in communication at its upstream end with said chamber and at its downstream end with said valve plate;
• third outlet passageway intermediate said valve plate and said outlet port in communication at its upstream end with said valve plate and at its downstream end with said outlet port;
• means to rotate said valve plate to align and misalign said first outlet aperture with said first outlet passageway and said second outlet aperture with said second outlet passageway to thereby open and close communication between said first and second outlet passageways and said third outlet passageway to vary at least the amount of fluid passing into said third outlet passageway;
• means for adjusting the maximum temperature of the fluid exiting from said outlet port including
• an axially extending stop flange on the exterior of said housing cap adjacent its top;
• an orienting stem ring having an opening having a rotational asymmetric shape to receive a complementary shaped stem at only one rotated orientation, and an annular shaped seat cavity;
• and
• a disc shaped stop member having a central opening to receive said stem, an axially protruding annular section complementary to said annular shaped seat cavity so that said stop member can be received in said seat cavity in a plurality of rotated positions, and a stop shoulder adapted to engage said stop flange to prevent further rotational movement of said stop member;
• and
• means within said chamber to even the pressures of the fluids from said first and second supply ports that are delivered to said outlet port.