Patents by Inventor Gene E. Robinson

Gene E. Robinson 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).

  • Tractor hydraulic fluid
    Patent number: 5888946
    Abstract: The invention includes a tractor hydraulic fluid composition containing a major amount of a base oil mixture. The base oil mixture includes a first mineral oil having a kinematic viscosity at 100.degree. C. of at least about 4.0 centistokes and a second mineral oil having a kinematic viscosity at 100.degree. C. of at least about 7.0 centistokes. The tractor hydraulic fluid composition also contains a first polymethacrylate viscosity index improver and a second polymethacrylate viscosity index improver having a lower shear stability index than the first polymethacrylate viscosity index improver. The tractor hydraulic fluid composition has an unsheared kinematic viscosity at 100.degree. C. of at least about 9.1 centistokes, a sheared kinematic viscosity at 100.degree. C. of at least about 7.1 centistokes, and an unsheared kinematic viscosity at -40.degree. C. of not more than about 20,000 centipoise.
    Type: Grant
    Filed: December 30, 1997
    Date of Patent: March 30, 1999
    Assignee: Chevron U.S.A. Inc.
    Inventors: John A. Zakarian, Gene E. Robinson