| 摘要 |
<p>A self cleaning drip irrigation hose comprising an elongated strip of plastic film (10) folded longitudinally to form first and second overlapping longitudinal margins (12, 14). A first longitudinal bead (16) partially seals the overlapping margin. A second longitudinal bead (18) outboard of the first bead partially seals the overlapping margins (12, 14). The first and second beads (16, 18) have a repeating longitudinal pattern that forms a flow regulating channel (19) and opposing inlets (22, 24) spaced along the length of the first and second beads (16, 18). Outlets (30) from the flow regulating channel (19) to the exterior of the hose are spaced from the inlets (22, 24) to create a pressure drop. A third longitudinal bead (26) outboard of the second bead (18) completely seals the overlapping margins (12, 14). The second and third beads (18, 26) form a water access channel to the inlets (24) in the second bead (18) such that the inlets (22) in the first bead (16) when plugged are back flushed by water flow through the inlets (24) in the second bead (18).</p> |
