US Patent 7143777 Control valve having pressure balance effect

A control valve includes a housing, two sealing gaskets, a shaft, a protective jacket, a fixed plate, a movable plate, a sleeve, a pressure balance unit, and an urging screwing member. Thus, the movable plate is rotated by operation of the shaft without producing deviation or loose displacement so as to balance the water pressure and control the water output and temperature exactly. In addition, the movable plate is driven by the shaft to rotate relative to the fixed plate without producing friction and wear between the movable plate and the fixed plate, thereby enhancing the lifetime of the control valve.