Patent attributes
An improved rotating stream sprinkler of the type having a rotatable spray head with an offset nozzle port through which a water stream is projected outwardly, resulting in a reaction force for rotatably driving the spray head to sweep the water stream over a surrounding terrain area. The spray head is rotatably mounted on a body adapted for connection to a pressurized water supply, with interengaging bearing components providing predetermined friction brake torque resisting spray head rotation. By appropriately designing the nozzle port area and offset geometry, drive torque and brake torque is maintained at a substantially constant ratio for relatively slow and substantially constant spray head rotational speed over a range of normal water supply operating pressures. A downthrust spring retains the bearing components in engagement when the water supply is turned off, but does not contribute to friction brake torque when the water supply is turned on.
