Patents Assigned to T-Systems, International
  • Patent number: 5123984
    Abstract: In a high speed method and apparatus for forming inlet and/or outlet ports in drip irrigation hose, the surface of one margin of a continuous length of plastic film is deformed without puncturing at periodic intervals along its length corresponding to the locations of the inlet and/or outlet ports to form protrusions from the film surface. Thereafter, the protrusions are severed from the film to form the ports. The remainder of the hose is made in a conventional fashion. Preferably, the film surface is deformed by directing the film through the nip of pair of rotating wheels. On the surface of one of the wheels is a series of blunt projections sized, shaped and positioned to correspond to the ports being formed. The protrusions are severed by the edge of a knife across which the film is directed.
    Type: Grant
    Filed: August 17, 1990
    Date of Patent: June 23, 1992
    Assignee: T-Systems International, Inc.
    Inventors: Davies Allport, David Giuntoli, William F. Holzer