Patent ID: 6193169
Filing Date: 2001-02-27
Classification: B05B

Abstract:
A rotating nozzle for spraying jets of fluid, said nozzle comprising a housing having an interior chamber with a fluid inlet and a bearing bore which defines a cylindrical radial bearing surface and an outwardly extending substantially flat axial bearing surface in said chamber, a shaft rotatably supported by said radial bearing surface and extending into said chamber from outside of said housing, said shaft having a radially projecting shoulder defining a substantially flat axial bearing surface located in said chamber adjacent an end of the axial bearing surface defined by said bearing bore for cooperation with the axial bearing surface defined by said bearing bore to form a friction brake in response to the introduction of pressurized fluid into said inlet and chamber, a nozzle head rotatable with said shaft outside of said chamber and having angularly spaced fluid outlets, said shaft defining a passage for establishing fluid communication between said fluid inlet and said fluid outlets, a turbine located in said chamber and coupled directly to said shaft in coaxial relation therewith, a fluid supply for directing pressurized fluid from said inlet, through said chamber and toward said outlets for acting on said turbine to rotate said shaft and nozzle head while simultaneously directing liquid through said passage and outlets, said turbine having surface areas exposed to pressurized fluid in said chamber on upstream and on downstream sides thereof, said turbine surface area on said upstream side being exposed to greater pressure induced forces than said surface area on the downstream side resulting from fluid pressure within said chamber for urging said shaft and the axial bearing surface thereof toward the axial bearing surface defined by said bearing bore, said housing bearing bore being operable for supporting said shaft and nozzle head for rotation at a speed which increases substantially proportional to increases in pressure at said fluid inlet until said pressure reaches a first predetermined value, and said friction brake formed by said axial bearing surfaces cooperating to brake rotational movement of said shaft and nozzle as a result of said axial bearing surfaces being moved toward each other to increase frictional resistance therebetween in response to pressure in said chamber above said first predetermined value acting to force said shoulder axial bearing surface in an axial direction toward said axial bearing surface defined by said bearing bore for limiting rotation of said shaft to a substantially constant speed not exceeding about 35 rpm notwithstanding a substantial increase in pressure from said first predetermined value to a second predetermined value.