Patents by Inventor Heather M. Armistead

Heather M. Armistead 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).

  • Hydraulic system having dual tilt blade control
    Patent number: 8893818
    Abstract: A hydraulic system for a machine is disclosed. The hydraulic system may have a tank configured to hold a supply of fluid, a pump configured to draw fluid from the tank and pressurize the fluid, a first cylinder operatively connected between a first side of a work tool and an undercarriage of the machine, and a second cylinder operatively connected between a second side of the work tool and the undercarriage of the machine. The hydraulic system may also have a first electro-hydraulic valve associated with the first cylinder and configured to selectively regulate a flow of pressurized fluid to the first cylinder independently of the second cylinder, and a second electro-hydraulic valve associated with the second cylinder and configured to selectively regulate a flow of pressurized fluid to the second cylinder independently of the first cylinder.
    Type: Grant
    Filed: November 8, 2011
    Date of Patent: November 25, 2014
    Assignee: Caterpillar Inc.
    Inventors: Timothy L. Hand, Heather M. Armistead, Fuaad A. Sayeed, Srikalyan C. Puranam, Stephen C. Garnett
  • HYDRAULIC SYSTEM HAVING DUAL TILT BLADE CONTROL
    Publication number: 20120152575
    Abstract: A hydraulic system for a machine is disclosed. The hydraulic system may have a tank configured to hold a supply of fluid, a pump configured to draw fluid from the tank and pressurize the fluid, a first cylinder operatively connected between a first side of a work tool and an undercarriage of the machine, and a second cylinder operatively connected between a second side of the work tool and the undercarriage of the machine. The hydraulic system may also have a first electro-hydraulic valve associated with the first cylinder and configured to selectively regulate a flow of pressurized fluid to the first cylinder independently of the second cylinder, and a second electro-hydraulic valve associated with the second cylinder and configured to selectively regulate a flow of pressurized fluid to the second cylinder independently of the first cylinder.
    Type: Application
    Filed: November 8, 2011
    Publication date: June 21, 2012
    Inventors: Timothy L. Hand, Heather M. Armistead, Fuaad A. Sayeed, Srikalyan C. Puranam, Stephen C. Garnett