Patent ID: 8267111

Claim:
A pressure balance valve comprising a housing including a first peripheral wall, a first end wall, and a second end wall to define an internal chamber; the first peripheral wall including a cylinder cavity defined therein to form most part of the internal chamber, and the cavity including two annular first openings arranged on two ends thereof respectively; the first peripheral wall including a first inlet to flow cold water and a second inlet to flow hot water, both of which are in communication with the cavity so that the cold and the hot waters from the first and the second inlets respectively flow into the cavity, and including a first outlet to flow the cold water and a second outlet to flow the hot water, both of which communicate with the cavity so that the cold and the hot waters from the cavity flow out of the first and the second outlets individually; the first and the second end walls including a first and a second limiting elements to limit flowing amount disposed on inner surfaces thereof respectively; a valve core including a first loop, a second loop, and a pressure sensing cliff between the first and the second loops; the valve core including a cold-water pressure room defined between one side of the pressure sensing cliff and the first loop, and including a hot-water pressure room defined between another side of the pressure sensing cliff and the second loop; the valve core being slidably fitted to the cavity to slide axially; the valve core including at least one first pore to flow the cold water defined between the first loop and the pressure sensing cliff so as to communicate with the cold-water pressure room and the first inlet, and including at least one second pore to flow the hot water defined between the second loop and the pressure sensing cliff so as to communicate with the hot-water pressure room and the second inlet; the cavity including two annular first openings arranged on two ends thereof and defined by the first and the second loops respectively, and the first and the second limiting elements being placed in the first openings of the first and the second loops so that cross sectional areas of the first openings to flow the cold and the hot waters are decreased to be less than those of the first and the second inlets.