Patents Assigned to Plastro Gvat
  • Patent number: 5730365
    Abstract: A rotary sprinkler includes a rotor rotatably mounted with respect to a nozzle to be impinged and to be rotated by the water jet from the nozzle, and a sleeve circumscribing the nozzle and formed with an open end through which the water jet is discharged laterally of the nozzle. The rotor is displaceable axially of the nozzle. A spring normally urges a closure-surface of the rotor against the open end of the sleeve to close it against the entry of foreign matter, but is deformable by the water jet to displace the closure surface of the rotor axially away from the sleeve.
    Type: Grant
    Filed: October 19, 1995
    Date of Patent: March 24, 1998
    Assignee: Plastro Gvat
    Inventor: Daniel Messinger
  • Patent number: 5695122
    Abstract: A rotary sprinkler has a step-down transmission between a turbine wheel drive and the sprinkler nozzle, which transmission includes a fixed ring gear having internal teeth coaxial with the drive rotary axis; a planet gear having external teeth engageable with, but fewer in number than, the internal teeth of the ring gear; and an eccentric pin secured to the rotary drive at its rotary axis and having a central axis laterally of the drive rotary axis. The eccentric pin is received within an opening centrally of the planet gear to cause the planet gear to planetate around the fixed ring gear and to rotate around the drive rotary axis at a step-down velocity determined by the difference in the number of teeth between the ring gear and the planet gear.
    Type: Grant
    Filed: November 8, 1995
    Date of Patent: December 9, 1997
    Assignee: Plastro Gvat
    Inventor: Daniel Messinger
  • Patent number: 5636793
    Abstract: A rotary sprinkler and method of distributing water by providing two discharge nozzles on a rotor for discharging water outwardly of the sprinkler along axes extending preselected adjustable distances laterally of the rotary axis to provide moments tending to rotate the sprinkler in opposite directions, to enable the rotational speed and rotational direction of the rotor to be adjusted.
    Type: Grant
    Filed: July 25, 1995
    Date of Patent: June 10, 1997
    Assignee: Plastro Gvat
    Inventor: Yossef Gurevitch
  • Patent number: 5294058
    Abstract: A drip irrigation emitter includes an elastomeric membrane formed on one side with a recess having a flat bottom to define a thin wall section of substantially smaller thickness than the remainder of the elastomeric membrane, and with a flow-restrictor orifice centrally through the thin wall section and of much smaller cross-sectional area than that of the recess to produce a pressure drop in the fluid flowing therethrough to the emitter outlet opening. The membrane is deformable to enlarge or restrict the flow to the outlet opening in response to changes in the inlet pressure to thereby regulate the flow through the outlet opening.
    Type: Grant
    Filed: January 11, 1993
    Date of Patent: March 15, 1994
    Assignee: Plastro-Gvat
    Inventor: Zvi Einav
  • Patent number: 5200132
    Abstract: A method for manufacturing a drip irrigation emitter, including the steps of molding onto an injection-mold core having at least n different active diameters, n different, axially spaced apart members of the emitter, at least n-1 of the members being substantially annular, the inside diameter of at least one of the annular members being a tight fit on the outside diameter of the next smaller of the members, stripping the members off the core, starting from the member having the largest inside diameter, thereby causing the members to be tightly nested one inside the other, in a predetermined axial and angular relationship, and ejecting the thus fully assembled emitter from the mold. There is also provided an injection mold for producing fully assembled multi-part drip-irrigation emitters.
    Type: Grant
    Filed: August 5, 1991
    Date of Patent: April 6, 1993
    Assignee: Plastro Gvat
    Inventors: Adiel Shfaram, Avraham Zakay
  • Patent number: 5148825
    Abstract: A moisture-responsive valve includes a water-swellable body within a housing adjacent a moisture-permeable wall thereof for controlling the movements of a valve member with respect to a valve seat in response to the moisture passing through the moisture-permeable wall. The valve member is floatingly mounted between a first spring interposed between the valve member and the housing and urging the valve member away from the valve seat, and a second spring interposed between the valve member and the water-swellable body and urging the valve member towards the valve seat.
    Type: Grant
    Filed: November 20, 1991
    Date of Patent: September 22, 1992
    Assignees: Plastro-Gvat, Agroteam Consultants Ltd., Jacob Gil
    Inventors: Jacob Gil, Zvi Rubenstein
  • Patent number: 5007586
    Abstract: A rotary sprinkler comprises a nozzle outputting a jet axially thereof; a rotor rotatably mounted with respect to the nozzle in alignment with the axial jet and having a surface formation impinged by the axial jet to deflect the jet laterally of the nozzle and to rotate the rotor; and a retarding device having a first surface rotatable with the rotor with respect to the nozzle, a second surface non-rotatable with respect to the nozzle, and a viscous liquid between the first and second surfaces; characterized in that the first surface of the retarding device is a cavity formed in a surface of the rotor opposite to that having the surface formation impinged by the axial jet, and that the second surface of the retarding device is carried by a pin non-rotatably mounted with respect to the nozzle and disposed within the cavity.
    Type: Grant
    Filed: August 29, 1989
    Date of Patent: April 16, 1991
    Assignees: Agroteam Consultants Ltd, Plastro-Gvat
    Inventor: Amir Cohen
  • Patent number: 4886211
    Abstract: A rotary sprinkler includes a nozzle producing a jet axially of the nozzle, and a rotor configured to deflect the axial jet laterally of the nozzle. The rotor is formed with a socket receiving a pin, and a high viscosity fluid in the rotor socket is effective to apply a retarding force to the rotor during its rotation with respect to the pin.
    Type: Grant
    Filed: March 29, 1988
    Date of Patent: December 12, 1989
    Assignees: Agroteam Consultants Ltd. 2, Plastro-Gvat
    Inventor: Amir Cohen
  • Patent number: 4805838
    Abstract: A water sprinkler, comprises a distributor head and a direction-reversing member movably mounted with respect to the distributor head. The latter member includes first and second surfaces impinged by the water jet in first and second positions of the direction-reversing member, a third surface contactable with the distributor head for rotating it in one direction when the first surface is impinged by the water jet, and a fourth surface contactable with the distributor head for rotating it in the opposite direction when the second surface is impinged by the water jet. The sprinkler further includes an abutment, and a pair of stops engageable by the abutment after the distributor head has been rotated a predetermined distance in the one or opposite direction, to switch the direction of rotation of the distributor head.
    Type: Grant
    Filed: August 9, 1988
    Date of Patent: February 21, 1989
    Assignees: Plastro Gvat, Agroteam Consultants Ltd.
    Inventor: Ilan Greenberg
  • Patent number: 4763839
    Abstract: A sprinkler comprises a nozzle and a distributor head mounted for both rotary and lateral movements with respect to the nozzle. The distributor head has two passageways formed such that when it receives the water jet in one or the other passageway, it directs the jet outwardly of the distributor head with the water applying a force tending to rotate the distributor head in one or the other direction. The sprinkler further includes an abutment, a first stop engageable by the abutment when the distributor head is rotated in the one direction by the flow of water through the first passageway to move the distributor head laterally of the nozzle to align its second passageway with the nozzle, and a second stop engageable by the abutment when the distributor head is rotated in the opposite direction by the flow of water through the second passageway to move the distributor head laterally of the nozzle to align its first passageway with the nozzle.
    Type: Grant
    Filed: January 27, 1987
    Date of Patent: August 16, 1988
    Assignees: Plastro Gvat, Agroteam Consultants Ltd.
    Inventor: Ilan Greenberg
  • Patent number: 4760958
    Abstract: A sprinkler comprises a nozzle head connectable to a source of pressurized water and including a nozzle bore through which the water issues in the form of a jet, and a rotary deflector having an underface formed with a radial array of grooves each having axially-extending inlet ends, radially-extending outlet ends, curved junctures joining the two ends, and curved bottom faces, which grooves are impinged by the water jet and deflect the jet laterally of the sprinkler while rotating the deflector. An adjustable mounting is provided for the rotary deflector enabling it to be mounted with its rotary axis at a plurality of different positions with respect to the axis of the nozzle bore, to vary the water distribution pattern produced by the rotary deflector laterally of the spinkler.
    Type: Grant
    Filed: January 27, 1987
    Date of Patent: August 2, 1988
    Assignee: Plastro Gvat and Agroteam Consultants Ltd.
    Inventor: Ilan Greenberg
  • Patent number: 4735363
    Abstract: An emitter for a drip irrigation line is substantially rigid and has a generally L-like shape having a shorter and a longer limb which is insertable into a length of tubing constituting the irrigation line from the outside thereof. The longer, elongated limb of the emitter consists of a body portion having a flow-attenuator through which irrigation liquid enters the emitter. The shorter limb of the emitter has a neck portion through which irrigation exits the emitter. A method for producing a drip irrigation line is also provided.
    Type: Grant
    Filed: May 15, 1986
    Date of Patent: April 5, 1988
    Assignee: Plastro Gvat
    Inventors: Adiel Shfaram, Avraham Zakay
  • Patent number: 4717076
    Abstract: A vortex sprinkler having a vortex chamber delimited in the downward direction by a bottom surface and in the upward direction by a rimmed opening leading to the atmosphere, at least one liquid inlet leading substantially tangentially into the vortex chamber, and a plurality of slots cut across the rim of the opening, wherein the slots are cut in a direction substantially tangential with respect to the vortex chamber.
    Type: Grant
    Filed: August 5, 1986
    Date of Patent: January 5, 1988
    Assignee: Plastro Gvat
    Inventor: Yosef Notkin