Patent ID: 8246082

Claim:
A sprinkler head riser apparatus for an in-ground sprinkler system, the apparatus comprising: an extendible pipe comprising first and second pipe portions each having an interior; a sprinkler head assembly attached to the extendible pipe; a cylinder having an end wall and an open end, said cylinder being connected to the first pipe portion; and a piston having an end wall, said piston being receivable in slidable and sealable engagement with said cylinder, said piston being connected to the second pipe portion, wherein said cylinder and said piston end wall define a first chamber fluidly isolated from the interiors of the first and second pipe portions, said first chamber being adapted to receive a first control fluid for displacing said piston relative to said cylinder to vary a distance separating an end of the first pipe portion and an end of the second pipe portion while permitting fluid communication between the first and second pipe portions, said first chamber comprising a cushioning region in communication with said first chamber.