Patent References 3896999 Drip level irrigation Water dropping type irrigation pipe Drip irrigation system Plastic web with multiplicity of gas filled bubbles, containing printing thereon and method of making same Drip irrigation conduit and method of making the same Drip irrigation conduit and method of making the same Irrigation hose with linear turbulent flow emitter Pressure compensating drip irrigation system Drip irrigation devices and plastic films with copper powder incorporated InventorsAssigneeApplicationNo. 339593 filed on 11/14/1994US Classes:156/244.13, Hollow article or lamina156/203, And edge-joining of one piece blank to form tube156/218, Hollow cylinder article156/244.22, Bonding spaced preforms156/244.27, Pressure assisted bonding239/542, CONDUIT OR NOZZLE ATTACHED IRRIGATION-TYPE DECELERATOR264/171.12Hollow preformExaminersPrimary: Stemmer, DanielAttorney, Agent or FirmInternational ClassesB29C 047/02B05B 015/00 AbstractA process for making low cost drip irrigation lines comprises molding a drip emitter having an elongated labyrinthine channel formed in the depth of the emitter body. Emitters of other configurations also can be used in the process. A plastic film is extruded and passed through a film die with an air injection tube at one end forming a plastic film bubble. At the bottom of the extruded plastic film bubble a pair of pressure rolls join opposite faces of the bubble to form a continuous unitary extruded plastic film sheet. The emitters are moved in series toward the nip of the pressure rolls and are inserted in sequence with their labyrinthine faces facing toward the hot bubble. The emitters are bonded to the extruded film sheet using the heat of extrusion, and the external sheet forms one face of the labyrinthine channel through each emitter. After laminating the emitter to the extruded film, an exit hole is formed through the film to each emitter and the film is then wrapped and bead sealed to form a continuous flexible drip irrigation tube with the emitters spaced apart along the inside of the tube. The process can be used for making multiple drip irrigation lines in parallel along a single extruded plastic film sheet.Field of SearchCONDUIT OR NOZZLE ATTACHED IRRIGATION-TYPE DECELERATORDISTRIBUTOR OR NOZZLE IN CIRCUMFERENTIAL WALL OF FLEXIBLE SUPPLY LINE Hollow article or lamina After bonding; e.g., as finishing step, etc. Bonding spaced preforms Post-treatment Pressure assisted bonding And edge-joining of one piece blank to form tube Hollow cylinder article Reshaping product (extrudate) subsequent to extrusion Hollow preform Having particular noncircular cross-section (e.g., T-configured, etc.) | |