A diverter valve comprises a housing having inlets, a first outlet, and a second outlet. The inlets are connected to hot and cold water supplies, and mixing of the hot and cold water occurs both inside the housing and inside a
mixing chamber external to the valve. The first outlet is connected to a spout, and the second outlet is connected to a spray unit. A valve element is mounted in the housing, movable between a closed position and an open position with respect to the first outlet. A
piston member comprising a first
piston at the bottom end of the valve element, and a second smaller
piston at the top end of the valve is responsive to pressure differential between the second outlet and the inlet for movement to a first and second position. When a lower pressure exists at the second outlet, the piston member moves to the second position, closing off the first outlet. The valve also includes a flow
regulator to regulate the flow through the second outlet. Fluid is directed into the flow
regulator by channels running through the bottom piston. The flow
regulator allows pressure to build up inside the valve, providing an increased closure force on the second outlet when the first outlet is open. An inverted cup
washer prevents
fluid leakage from the second exit by any other
route than through the flow regulator. Build up of water inside this cup
washer pushes it against the housing, providing an anti-knocking mechanism. The diverter valve may be included in a faucet
assembly along with a separate isolated channel for filtered water.