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US Patent 3981452 - Irrigation pipes with dripper units and method of its manufacture
US Patent Issued on September 21, 1976
Estimated Patent Expiration Date:
September 21, 1993Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.
Estimated Patent Expiration Date:
September 21, 1993Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.AbstractAn irrigation pipe constitutes at predetermined spacings the outer sleeve of an irrigation unit, whose inner part comprises a cylinder with a peripheral helical groove. A method for producing such a pipe comprises feeding said cylinder at predetermined intervals into an extruder having an angular extrusion nozzle head and extruding said pipe around it, and after cooling said pipe sufficiently making at least one aperture therein aligned with the forward end of said groove in said cylinder. | InventorApplicationNo. 05/548736 filed on 02/10/1975US Classes:239/542CONDUIT OR NOZZLE ATTACHED IRRIGATION-TYPE DECELERATORField of Search239/542CONDUIT OR NOZZLE ATTACHED IRRIGATION-TYPE DECELERATORExaminersPrimary: Song, Robert R.Assistant: Church, Gene A. Attorney, Agent or FirmUS Patent References3604728, 3729142, 3806036, 3887138, 3897009International ClassesA01G 25/02 (20060101)B29C 47/02 (20060101) A01G 25/00 (20060101) |
