Irrigation sprinkler and valve with flushing system

An improved pop-up irritation sprinkler of the type having a cylindrical case with a bearing guide, a pop-up stem slidably disposed therein, a pop-up seal, and a retracting spring, wherein the improvement comprises sprinkler seal means on the bearing guide such as to provide a vertically flexible barrier between intruding foreign matter and the interface between the pop-up stem and the bearing guide, wherein said sprinkler seal means further comprises:

• a) the bearing guide sealably retained within an upper end of the sprinkler case contiguous with the retracting spring and the pop-up seal,
• b) barrier seal retaining means on said bearing guide, and
• c) a resilient barrier seal attached to said bearing guide by said barrier seal retaining means, closely surrounding the pop-up stem and maintaining a close fit so as to exclude foreign matter from the interface between the pop-up stem and the bearing guide, and yet able to flex downward with the pop-up stem enough to allow the pop-up seal to open and thus create a flowpath for flushing, said resilient barrier seal having radial slits in its inner circumference to permit sufficient flexibility to accommodate adequate flushing flow.

An improved separate irrigation flow control valve of the type having a body, a valve seat, a bonnet, a pilot flow exit port, and a piston, each with an internal flow passage to accommodate continuous pilot flow through the bonnet chamber when the valve is open, a piston spring, sealing means positioned between the bonnet and the piston, and a valve seal contiguously engageable between the piston and the valve seat, wherein the improvement comprises:

• a) means for producing a closing rate sufficiently slow near the end of the closing stroke to eliminate potentially destructive supply line pressure surges upstream of the valve, and facilitate flow interruption prior to final closure, and
• b) flow interrupting means for producing a brief flushing cycle to wash away debris from between sprinkler stems and bearing guides.