Patents by Inventor Bahram S. Rajabi

Bahram S. Rajabi 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: 8695643
    Abstract: A reduced weight and repairable piston accumulator. The accumulator includes a load bearing metallic cylinder with removable end caps secured thereto with slip flanges for allowing repairability and for achieving the required cycle life. The cylinder serves as the surface on which the piston slides and is designed such that it sustains the axial stress induced by pressurization of the accumulator. A composite over wrapping is designed such that it sustains the stress in the hoop (radial) direction. A stress transitioning bushing can be provided for transitioning hoop stresses between the overwrap and the slip flange. When combined with the cylinder, the fibers of the composite wrap will not be placed in shear and thus will not fatigue in the same manner as some prior art designs.
    Type: Grant
    Filed: November 10, 2008
    Date of Patent: April 15, 2014
    Assignee: Parker-Hannifin Corporation
    Inventors: Bahram S. Rajabi, Allen R. Hansen
  • Patent number: 7984731
    Abstract: A lightweight high pressure repairable piston composite tie-rod accumulator that does not use a load bearing metallic liner. An exemplary accumulator includes composite tie rods that sustain the axial stress induced by pressurization of the accumulator, while the shell is designed such that it sustains the stress of pressurization in the hoop direction. The tie rods can be secured using a wedge-type tie rod retention mechanism. As a result, no pretension is applied to the tie rods and the composite shell may be designed entirely for hoop stress.
    Type: Grant
    Filed: November 13, 2008
    Date of Patent: July 26, 2011
    Assignee: Parker-Hannifin Corporation
    Inventors: Bahram S. Rajabi, Allen R. Hansen
  • Publication number: 20090126816
    Abstract: A lightweight high pressure repairable piston composite tie-rod accumulator that does not use a load bearing metallic liner. An exemplary accumulator includes composite tie rods that sustain the axial stress induced by pressurization of the accumulator, while the shell is designed such that it sustains the stress of pressurization in the hoop direction. The tie rods can be secured using a wedge-type tie rod retention mechanism. As a result, no pretension is applied to the tie rods and the composite shell may be designed entirely for hoop stress.
    Type: Application
    Filed: November 13, 2008
    Publication date: May 21, 2009
    Inventors: Bahram S. Rajabi, Allen R. Hansen
  • Publication number: 20090126815
    Abstract: A reduced weight and repairable piston accumulator. The accumulator includes a load bearing metallic cylinder with removable end caps secured thereto with slip flanges for allowing repairability and for achieving the required cycle life. The cylinder serves as the surface on which the piston slides and is designed such that it sustains the axial stress induced by pressurization of the accumulator. A composite over wrapping is designed such that it sustains the stress in the hoop (radial) direction. A stress transitioning bushing can be provided for transitioning hoop stresses between the overwrap and the slip flange. When combined with the cylinder, the fibers of the composite wrap will not be placed in shear and thus will not fatigue in the same manner as some prior art designs.
    Type: Application
    Filed: November 10, 2008
    Publication date: May 21, 2009
    Inventors: Bahram S. Rajabi, Allen R. Hansen
  • Patent number: 6460571
    Abstract: An accumulator for a fluid system includes a canister and an end cap at one or both ends of the canister. The end cap has a cylindrical peripheral surface, with a groove or channel having gradually rounded or curved sidewalls, formed circumferentially around the cap, and spaced from the axial ends of the cap. An annular, radially-outward projecting flange is provided at the axially outer end of the cap, and serves as a locating feature for the cap when it is inserted into the canister. A forming tool such as a crimping machine is used to mechanically deform the canister into the groove. The rounded shape of the groove creates a permanent, fluid-tight attachment with the canister. The accumulator can include either a piston or bladder.
    Type: Grant
    Filed: December 19, 2001
    Date of Patent: October 8, 2002
    Assignee: Parker-Hannifin Corporation
    Inventors: Bahram S. Rajabi, Allen R. Hansen
  • Publication number: 20020129859
    Abstract: An accumulator for a fluid system includes a canister and an end cap at one or both ends of the canister. The end cap has a cylindrical peripheral surface, with a groove or channel having gradually rounded or curved sidewalls, formed circumferentially around the cap, and spaced from the axial ends of the cap. An annular, radially-outward projecting flange is provided at the axially outer end of the cap, and serves as a locating feature for the cap when it is inserted into the canister. A forming tool such as a crimping machine is used to mechanically deform the canister into the groove. The rounded shape of the groove creates a permanent, fluid-tight attachment with the canister. The accumulator can include either a piston or bladder.
    Type: Application
    Filed: December 19, 2001
    Publication date: September 19, 2002
    Inventors: Bahram S. Rajabi, Allen R. Hansen