Drip level irrigation

Abstract

An irrigation dripper unit for use in irrigation in association with an irrigation supply pipe and also, when combined with a supply pipe, to form together with the supply pipe an integral unit. The dripper unit can be connected in series with the supply pipe or, when constituting a part of the integral unit, is connected in series with the supply pipe and has means to tap off a portion of the water flowing through the unit and to discharge such portion at a low drip rate.

We claim: 
     
       1. An irrigation dripper unit to connect adjacent pipeline sections, comprising an outer tubular member and an inner tubular member, each having first and second opposite end portions, said inner tubular member being axially slidable into said outer tubular member, means retaining said inner tubular member within the outer tubular member, the first end portion of the outer tubular member being disposed adjacent and projecting beyond the second end portion of the inner tubular member, the first end portion of the inner tubular member being disposed adjacent and projecting beyond the second end portion of the outer tubular member, said first end portions of said tubular members serving to connect adjacent pipeline sections, a continuous elongated helical groove formed in the surface of one of the tubular members and defining a continuous conduit with respect to the contiguous surface of the other tubular member, one end of said helical conduit being disposed adjacent the second end portion of the inner tubular member and defining an inlet communicating with the interior of said inner tubular member, at least one port defining an outlet formed in said unit adjacent to and communicating with the opposite end of the helical conduit and the exterior of said unit whereby said conduit defines a continuously open path to the exterior of the unit, for flow of a portion of the fluid that may be flowing through the interior of said inner tubular member. 
     
     
       2. An irrigation dripper unit according to claim 1 and furthermore comprising pipeline sections respectively formed integrally with said first end portions of said tubular members. 
     
     
       3. A combined pipeline section and irrigation dripper unit comprising a pipeline section, an outer tubular member, a first end portion of said outer tubular member being formed integrally with one end of the pipeline section, an inner tubular member, a first end portion of the inner tubular member being formed integrally with the other end of the pipeline section, a continuous elongated helical groove formed in the surface of one of the tubular members of the unit, said inner tubular member being axially slidable into said outer tubular member, means retaining the inner tubular member associated with one pipeline section within the outer tubular member associated with a succeeding pipeline section so as to constitute an irrigation dripper unit, contiguous surfaces of the two tubular members defining between them a continuous elongated helical conduit, one end of said conduit communicating with an adjacent pipe section and defining an inlet and at least one port defining an outlet formed in said unit adjacent to and communicating with the opposite end of the conduit and the exterior of said unit whereby said conduit defines a continuously open path to the exterior of the unit, for flow of a portion of the fluid that may be flowing through the interior of said inner tubular member. 
     
     
       4. A combination according to claim 3 wherein said connecting means is formed of alternating recesses and slots formed peripherally in the second end portion of the outer tubular member and projections formed in corresponding positions of the inner tubular members. .Iadd. 5. An irrigation dripper unit to connect adjacent pipeline sections, comprising, an outer tubular member and   an inner tubular member,   each of said members having first and second opposite end portions, said inner tubular member being axially slidable into said outer tubular member,   means retaining said inner tubular member within the outer tubular member,   the first end portion of the outer tubular member being disposed adjacent and projecting beyond the second end portion of the inner tubular member,   the first end portion of the inner tubular member being disposed adjacent and projecting beyond the second end portion of the outer tubular member,   said first end portions of said tubular members serving to connect adjacent pipeline sections,   a continuous elongated groove formed in the surface of one of the tubular members and defining a continuous conduit with respect to the contiguous surface of the other tubular member,   said conduit being of a substantially lesser cross-sectional area than the cross-sectional area of said inner tubular member and having a substantially greater length than the axial lengths of said inner and outer tubular members,   one end of said conduit opening into the inner tubular member and defining an inlet communicating with the interior of said inner tubular member,   at least one port defining an outlet formed in said unit adjacent to and communicating with the opposite end of the conduit and the exterior of said unit whereby said conduit defines a continuously open path to the exterior of the unit for flow of a portion of the fluid that may be flowing through the interior of said inner tubular member and said portion will emerge from said outlet as a practically pressureless drip.   
     
     
        .Iaddend..Iadd. 6.  An irrigation dripper unit according to claim 5 wherein at least one pipeline section is formed integrally with one of said first end portions of at least one of said tubular members. .Iaddend..Iadd. 7. An in-line irrigation dripper unit to connect adjacent pipeline sections comprising: (a) an outer tubular member having an inner surfce and an inner tubular member having an outer surface;   (b) each member having first and second opposite end portions;   (c) said inner member being axially insertable into said outer member, without simultaneous rotation, into an operative position wherein said outer and inner surfaces are contiguous;   (d) means for retaining said inner and outer members in said operative position;   (e) the first end portion of the outer member being disposed adjacent and projecting beyond the second end portion of the inner member, and the first end portion of the inner member being disposed adjacent and projecting beyond the second end portion of the outer member;   (f) means on the first end portions of said members for connecting said unit to adjacent pipeline sections;   (g) an inlet port connecting the outer surface of the inner member with the interior of the inner member;   (h) an outlet port in the outer member connecting its inner surface with the exterior of the outer member;   (i) a continuous conduit formed in the contiguous surfaces of the members and interconnecting the inlet and outlet ports; and   (j) said conduit having flow restricting means for causing pressurized liquid entering the inlet port and passing through the conduit to emerge from the outlet port as a practically pressureless drip. .Iaddend..Iadd. 8. An irrigation dripper unit according to claim 7 wherein said inlet port is adjacent the second end portion of the inner member and is annular. .Iaddend.9. An in-line irrigation dripper unit according to claim 7 in combination with pipeline sections each of whose internal diameter is substantially the same as the internal diameter of the bore of the inner tubular member. .Iadd.10. An irrigation dripper unit to connect adjacent pipeline sections, comprising an outer tubular member and an inner tubular member, each member having first and second opposite end portions, said inner tubular member being axially slidable relative to said outer tubular member without simultaneous relative rotation to an operative position at which the inner surface of the outer member is contiguous to the outer surface of the inner member, means retaining said inner tubular member in its operative position within the outer tubular member, the first end portion of the outer tubular member being disposed adjacent the second end portion of the inner tubular member, the first end portion of the inner tubular member being disposed adjacent the second end portion of the outer tubular member, said first end portions of said tubular member serving to connect adjacent pipeline sections, a continuous elongated tortuous groove formed in the surface of one of the tubular members and defining a continuous conduit with respect to the contiguous surface of the other tubular member, one end of said conduit communicating with the interior of said inner tubular member and the opposite end of the conduit communicating with the exterior of said unit..Iaddend..Iadd.11. An irrigation dripper unit to connect adjacent pipeline sections comprising:   (a) an outer tubular member having an inner surface and an inner tubular member having an outer surface;   (b) each member having first and second opposite end portions;   (c) said inner member being axially insertable into said outer member, without simultaneous rotation, into an operative position wherein said outer and inner surfaces are contiguous;   (d) means for retaining said inner and outer members in said operative position;   (e) the first end portion of said outer member being formed integrally with one end of a pipeline section;   (f) means on the first end portion of said inner member for connecting to a pipeline section;   (g) an inlet port for connecting the outer surface of the inner member with the interior of the inner member;   (h) an outlet port in the outer member thereof for connecting the inner surface of the outer member with the exterior of the outer member; and   (i) a continuous conduit formed in the contiguous surfaces of the members and interconnecting the inlet and outlet ports;   (j) said conduit having flow restricting means for causing pressurized liquid, entering the inlet port and passing through the conduit, to emerge from the outlet port as a practically pressureless drip.