US Patent 7311588 Water grinder

A water grinder including: a housing in which a rotary shaft is drivably disposed, the rotary shaft being formed with an axial passage; a water incoming flow way formed in the housing; a valve disposed in the housing and controllable by a selection switch; an external water discharging assembly disposed at a front end of the housing and having at least one water outlet; and a water flow bypass communicating with the external water discharging assembly and the valve. By means of turning the selection switch, the valve can be turned to a position to conduct the water from the flow way into the passage of the rotary shaft to discharge therefrom. Alternatively, the valve can be turned to another position to conduct the water to flow into the external water discharging assembly to discharge from the water outlet. Accordingly, the water discharging position is controllable to achieve best wetting effect for the powder dust produced in grinding operation.