The present invention relates to pressure regulators for irrigation sprinklers, or the like, and especially to a pressure regulator having a generally direct flow of fluid through the center thereof and has a pressure controller for dampening the oscillations in the pressure regulator and in the pressure of the fluid passing therethrough.
In sprinkler irrigation systems, water is received from a source of water under pressure and is introduced into a main water supply pipe, which is connected with one or more distributing pipes forming a fluid conduit. The irrigation system provides a plurality of discharged irrigation sprinkler heads which may be of many different types, such as seen in our prior U.S. Pat. Nos. 4,062,494, 3,204,873, 3,204,874, 4,130,247, 3,669,356 and 3,627,025. Water pressure throughout pipelines tend to vary for a variety of reasons and as the pressure varies between two sprinklers having discharge orifices of exactly the same size, so does the output flow. The quantity of water discharged over any given period of time varies in relation to the variations in pressure; thus causing uneven distribution of water from a sprinkler system with a greater amount of water being discharged through sprinklers where the pressure is higher and a lesser amount through sprinklers where the pressure is lower. To counter this problem, pressure regulators have been developed which can be attached in the water line ahead of the sprinkler head to maintain constant pressure at the sprinkler head for all the sprinkler heads in the irrigation system. There have been a great variety of fluid pressure regulators for regulating the flow of fluid through a pipe in irrigation systems. These pressure regulators typically rely on a spring biasing a piston or other member in a passageway for opening or closing a portion of the passageway. However, the passageways typically go around the piston and follow a circuituous passage.
Some of the prior pressure regulators have, however, provided a more direct path through the pressure regulator applying pressure to a biasing means which in turn affects the flow through the pressure regulator. Typical prior pressure regulators may be seen in the following U.S. patents: Burnett U.S. Pat. No. 614,441; Benz et al., U.S. Pat. No. 2,219,408; Semon U.S. Pat. No. 3,407,841; Hazlet U.S. Pat. No. 343,125; Evans U.S. Pat. No. 2,888,949; Byrd U.S. Pat. No. 3,930,519; Teague U.S. Pat. No. 4,281,681; Moskow U.S. Pat. No. 3,890,999; Eickmeyer U.S. Pat. No. 3,888,033; Zakay U.S. Pat. No. 4,023,595; Meronek U.S. Pat. No. 3,837,463; Inglis U.S. Pat. No. 3,053,641; and in a U.S.S.R. Pat. No. 325,596 to Danilenko.
The present pressure regulator is similar to some of those taught in the prior art, but advantageously overcomes one of the serious problems in sprinkler head pressure regulators by providing a means for dampening oscillations in a throttling stem and thereby dampening variation in the pressure of the fluid passing through the pressure regulator.