Drip-irrigation emitter for mounting on a liquid supply-conduit

Claim 1

A drip-irrigation emitter for mounting on a liquid supply conduit perforated with a suitable orifice, said emitter comprising: a body (1) having an inside chamber opening to either side of said body through a liquid intake aperture (6) and a liquid discharge aperture (8), said body (1) being externally provided at its periphery with means (3,4) for fixing said body to said conduit, an elastic membrane (2) having a peripheral rim positioned within said chamber so as to divide it into upstream and downstream compartments (5, 7) from which issue respectively said intake aperture (6) and said discharge aperture (8), said downstream compartment (7) being bounded by a wall (9) of said body converging from the rim of said membrane (2) toward the discharge aperture (8) and designed to act as a progressive support for the membrane during deformations, said membrane being in the shape of a solid disk of elastic material and separating over its entire area said upstream compartment (5) from said downstream compartment (7), said membrane being kept in place throughout its periphery in such a manner that it may deform progressively under an increasing pressure in said conduit between first and second positions, said first position being that of said membrane at rest wholly detached from the converging wall (9), the second position being that wherein said membrane rests substantially against the entire surface of said convergent wall (9), said convergent wall (9) containing at least one flow channel (10) issuing in the downstream compartment (7) and extending from the rim of said membrane (2) toward said liquid discharge aperture (8) whereby said channel (10) is covered by the elastic membrane (2) over a variable length depending on its deformation, from zero length covered for said first position in which the membrane is separated from said convergent wall (9) to a maximum covered length corresponding to said second position wherein the membrane rests against the entire surface of said convergent wall (9), said at least one flow channel (10) connecting at said membrane (2) to a duct (11) in said body (1) and issuing into its upstream compartment (5).