Some mixing taps for hot and cold Water of the kind mentioned are already known, where the hollow mixing ball is made of metal, as for instance of steel, or of a synthetic resin, at least in its section with water inlet and outlet holes. To ensure the tightness at least of the water inlet holes, said ball interacts with gaskets which are coordinated to the feeding conducts of the two types of water. According to prior art said gaskets are made of rubber or a similar material and are usually pushed against the surface of the ball by individual springs.
This kind of sealing usually wears out as time goes by and requires a frequent maintenance to prevent dripping and loss of water. In fact, those gaskets are often subject to a quite heavy and rapid wear, especially owing to their contact with a metal ball where the rim of the water inlet holes, even if carefully finished, exert a rubbing and wearing action on the seals. Thus both seals and springs and furring as well require frequent replacements in order to prevent mixing taps from leaking.