Patents by Inventor Michael DeFrank

Michael DeFrank has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 5855324
    Abstract: The serpentine, turbulence inducing path lengths from the inlets to the outlets of the flow regulating passage of a continuous emitter drip irrigation hose are arranged in back to back fashion relative to the outlets in the sense that the chevrons angle away from each of outlets, so there is parallel turbulent flow from two inlets to each outlet. This doubles the flow rate from each outlet without changing the dimensions of the flow regulating passage.
    Type: Grant
    Filed: December 30, 1997
    Date of Patent: January 5, 1999
    Assignee: T-Systems International, Inc.
    Inventors: Michael DeFrank, Wayne Hackman, Shawn Shirvan
  • Patent number: 5722601
    Abstract: The serpentine, turbulence inducing path lengths from the inlets to the outlets of the flow regulating passage of a continuous emitter drip irrigation hose are arranged in back to back fashion relative to the outlets in the sense that the chevrons angle away from each of outlets, so there is parallel turbulent flow from two inlets to each outlet. This doubles the flow rate from each outlet without changing the dimensions of the flow regulating passage.
    Type: Grant
    Filed: July 15, 1996
    Date of Patent: March 3, 1998
    Assignee: T-Systems International, Inc.
    Inventors: Michael DeFrank, Wayne Hackman, Shawn Shirvan
  • Patent number: 5634595
    Abstract: A drip irrigation hose of the continuous emitter type in which the outlets from the regulating passage each comprise a single longitudinal slit. By controlling the length of the slits and the flexibility of the film, water drips from the outlets when the hose is pressurized without clogging when the hose is depressurized. The slits are sufficiently long and the film is sufficiently flexible so the water drips from the outlets when the hose is pressurized. The slits are sufficiently short and the film is sufficiently rigid so the outlets close completely when the hose is depressurized. An outlet forming wheel has a knife blade on its periphery. A backing wheel engages the outlet forming wheel to establish a first nip therebetween. The backing wheel has on its periphery a circumferential slot into which the knife blade fits at the first nip. A rib forming wheel has around its periphery impressions that define a desired track pattern for the ribs.
    Type: Grant
    Filed: May 20, 1996
    Date of Patent: June 3, 1997
    Assignee: T-Systems International, Inc.
    Inventors: Michael DeFrank, David Marchetti, David L. Teegardin
  • Patent number: 5522551
    Abstract: A drip irrigation hose of the continuous emitter type in which the outlets from the regulating passage each comprise a single longitudinal slit. By controlling the length of the slits and the flexibility of the film, water drips from the outlets when the hose is pressurized without clogging when the hose is depressurized. The slits are sufficiently long and the film is sufficiently flexible so the water drips from the outlets when the hose is pressurized. The slits are sufficiently short and the film is sufficiently rigid so the outlets close completely when the hose is depressurized. An outlet forming wheel has a knife blade on its periphery. A backing wheel engages the outlet forming wheel to establish a first nip therebetween. The backing wheel has on its periphery a circumferential slot into which the knife blade fits at the first nip. A rib forming wheel has around its periphery impressions that define a desired track pattern for the ribs.
    Type: Grant
    Filed: July 19, 1994
    Date of Patent: June 4, 1996
    Assignee: T-Systems International, Inc.
    Inventors: Michael DeFrank, David Marchetti, David L. Teegardin
  • Patent number: 5458712
    Abstract: A hose is made by continuously transporting a first strip of plastic film through an assembly station. One or more contiguous molten beads are deposited onto a central region of the film. The beads are formed into a flow regulating passage defined by side walls. A second strip of plastic film, which is narrower than the first strip of film, is sealed to the side walls while molten to form a flow regulating passage between the sidewalls and the first and second strips of film. Inlets to the flow regulating passage and outlets from the flow regulating passage are formed at spaced intervals along the hose. The first strip of film is longitudinally folded to overlap the margins and the overlapping margins are sealed to complete the hose.
    Type: Grant
    Filed: May 13, 1994
    Date of Patent: October 17, 1995
    Assignee: T-Systems International, Inc.
    Inventor: Michael DeFrank
  • Patent number: 5333793
    Abstract: A laminar flow section and a turbulent flow section are formed contiguous to each other along the length of a flow regulating passage in a drip irrigation hose. Responsive to the pressure in a water supply passage of the drip irrigation hose, the cross-sectional area of the laminar flow section is reduced as the pressure increases so as to compensate for the effect of pressure changes on the drip flow rate of the hose. The water supply passage is formed by a continuous strip of plastic film sealed together at its margins, and the flow regulating passage has longitudinal side walls extending inwardly from the strip. The base portion of the side walls has chevron shaped surfaces that form the turbulent flow section and the remainder of the side walls has smooth surfaces that form the laminar flow section.
    Type: Grant
    Filed: July 21, 1993
    Date of Patent: August 2, 1994
    Assignee: T-Systems International, Inc.
    Inventor: Michael DeFrank