Patent ID: 8602320

Claim:
A nozzle for use with a pressurized liquid, comprising: a first and second nozzle member, at least one of said first or second nozzle member being movable with respect to the other nozzle member to provide an orifice having a variable area therebetween for spraying the pressurized liquid therefrom; at least one spring biasing said first and second nozzle members toward a closed position in which the orifice is closed, said spring having a force counteracted by a force of the pressurized liquid during dynamic operation of the nozzle to move the movable nozzle member and change the orifice area; electrical drive apparatus providing rotary power; a nozzle shaft connected to the movable nozzle member, said nozzle shaft driven by said electrical drive apparatus for rotating said movable nozzle member; and a spring force adjustment mechanism for adjusting the force of the spring to thereby adjust the force by which the pressurized liquid moves the movable nozzle member.