Intermittent sprinkler

Intermittent sprinkler apparatus comprising:

• a housing and an expandable water accumulating reservoir disposed within said housing, said housing defining an air space generally surrounding said reservoir,
• means for supplying irrigating water through said housing to said reservoir,
• nozzle means on said housing providing a discharge outlet from said reservoir,
• blocking means moveable between a first position blocking said nozzle means, and a second position exposing water discharge path from said reservoir through said nozzle means, and discharge means responsive to the pressure of water accumulated in said reservoir exceeding a predetermined threshold level for moving the blocking means from said first to said second position, and for returning said blocking means to said first position when said reservoir pressure falls below a second threshold level following discharge of water through said nozzle, said first threshold level corresponding to a pressure at which said reservoir means is substantially expanded,
• said means for moving the blocking means including a flexible, resilient diaphragm forming a portion of the reservoir and coupling means for coupling said diaphragm with said blocking means, said diaphragm normally urging the blocking means towards said first position, and
• an air plenum within said housing on the opposite side of said diaphragm from said water accumulating reservoir, and air conduit means connecting said air space with said air plenum.

An intermittent sprinkler, comprising:

• an outer housing,
• a water discharge nozzle in said housing,
• water inlet means for introducing irrigating water into said housing,
• an expandable bladder means mounted within said housing to receive water entering said housing through said inlet means, said bladder means forming a reservoir for accumulating supply water,
• a casing means mounted within said housing surrounding said bladder means generally lateral to the direction of discharge through said nozzle, said casing means defining an outer expansion limit for said bladder means said casing means being located within said housing to leave an air space between it and the outer housing wall,
• an outlet means positioned at one end of said reservoir formed by said bladder means,
• a flexible, resilient diaphragm mounted at the other end of said bladder means from said nozzle and forming a portion of the reservoir wall, said diaphragm normally assuming an inward position toward said nozzle, a blocking plug for said nozzle;
• and
• connector rod means carrying said plug at one end and engaging said diaphragm at its other end, said connector rod means normally holding said plug in a position blocking a discharge of water from the reservoir through said nozzle, said diaphragm being outwardly reflexible in response to an increase in pressure within said reservoir to move said plug away from said blocking position,
• the above elements being selected such that the plug is held in a blocking position during accumulation of water within the reservoir until said bladder means has expanded substantially to the limit defined by said casing means and said diaphragm flexes outwardly in response to further water accumulation, thereby permitting the discharge of water from said reservoir through said outlet means by contraction of said bladder means back to an original shape.