Patents by Inventor Douglas Dohallow

Douglas Dohallow 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: 6851349
    Abstract: A telescopic cylinder comprised of an outer cylinder, a plurality of decreasing diameter piston/sleeve assemblies concentrically mounted in the outer cylinder for reciprocal axial movement relative thereto, and a plunger assembly concentrically mounted within the innermost one of the piston/sleeve assemblies for reciprocal axial movement relative thereto. The piston/sleeve and plunger assemblies having a piston with at least one lateral hole and at least one lateral passage, respectively, extending into its interior, and in fluid communication with a passage in the outer cylinder for receiving pressurized fluid. Each lateral hole having an orifice surface located at the radially outermost portion of the hole and having a diametral dimension no smaller than the maximum diametral dimension of the hole. Each piston further having at least one longitudinally relieved portion located on its outer circumferential surface extending from a first end towards a second end.
    Type: Grant
    Filed: March 5, 2003
    Date of Patent: February 8, 2005
    Assignee: Parker-Hannifin Corporation
    Inventor: Douglas Dohallow
  • Publication number: 20030167916
    Abstract: A telescopic cylinder comprised of an outer cylinder, a plurality of decreasing diameter piston/sleeve assemblies concentrically mounted in the outer cylinder for reciprocal axial movement relative thereto, and a plunger assembly concentrically mounted within the innermost one of the piston/sleeve assemblies for reciprocal axial movement relative thereto. The piston/sleeve and plunger assemblies having a piston with at least one lateral hole and at least one lateral passage, respectively, extending into its interior, and in fluid communication with a passage in the outer cylinder for receiving pressurized fluid. Each lateral hole having an orifice surface located at the radially outermost portion of the hole and having a diametral dimension no smaller than the maximum diametral dimension of the hole. Each piston further having at least one longitudinally relieved portion located on its outer circumferential surface extending from a first end towards a second end.
    Type: Application
    Filed: March 5, 2003
    Publication date: September 11, 2003
    Inventor: Douglas Dohallow