Flow volume adjustment device for irrigation sprinkler heads

In an adjustable arc spray nozzle connectable with a source of pressurized fluid for providing a spray pattern radially disposed about the nozzle, the nozzle including a top member and a base member connected to the top member, a discharge orifice formed in a discharge plane between the top member and the base member, and means mounted on the top member for controlling a radius of the pattern, the improvement in the adjustable arc spray nozzle comprising:

• an internal helix member for controlling the arc of the spray pattern of the nozzle, the internal helix member being inserted into the top member, the internal helix member having an internal threaded channel, and the internal helix member having means for preventing the internal helix member from rotating with respect to the top member and the base member, the internal helix member having a helically configured surface extending about the circumference of the internal helix member, whereby as the internal helix member is moved downwardly the arc of the spray pattern of the nozzle increases, and as the internal helix member is moved upwardly the arc of the spray pattern of the nozzle decreases;
• and
• an internal flow adjustment screw for controlling the flow of the nozzle, the internal flow adjustment screw extending axially through the internal threaded channel of the internal helix member between the top member and base member, whereby upon rotation of the internal flow adjustment screw the internal helix member moves axially in the internal portion of the assembly to control the flow of water through the discharge orifice of the nozzle proportional to the arc of the spray pattern.