Patents by Inventor John S. Field

John S. Field 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: 5750884
    Abstract: The viscometer (100) includes a difference amplifier (110) driven by a signal generator (111) which supplies a control signal to shaker (120), which is sufficiently powerful to impose such strains as may be demanded by a controlling reference voltage with a desired form. The shaker (120) drives a shaft (125), and an upper plate (130) is attached to a distal end of the shaft (125). A lower plate (140) is positioned adjacent, and substantially parallel to, upper plate (130), thereby creating a space that may be filled by fluid sample (150). The motion of the upper plate h(t) is measured by a sensor (180). Plate (140) is mounted on force measuring means (160) which keeps lower plate (140) substantially motionless relative to frame (165). Force measuring means (160) provides an output, or force, signal f(t) that is indicative of the force which fluid sample (150) exerts on plate (130 and 140) in response to the movement of upper plate (130).
    Type: Grant
    Filed: November 25, 1996
    Date of Patent: May 12, 1998
    Assignee: Commonwealth Scientific and Industrial Research Organisation
    Inventor: John S. Field
  • Patent number: 5067346
    Abstract: A penetration measuring apparatus comprising a stage for mounting a sample of the material to be tested thereon, a probe having one end thereof proximal to the stage and having a longitudinal axis extending orthogonally of the stage, an ultra-microhardness indenter located in the one end of the probe, and a carriage assembly to which the probe is connected via an intermediate member, a first elastic connector of known stiffness connecting the probe to the intermediate member and a second elastic connector of known stiffness connecting the intermediate member to the carriage. The first and second connectors allow axial movement of the probe but prevent movement of the probe in any other direction. A driving device is provided for driving the carriage towards and away from the stage and a first measuring device measures the movement of the probe relative to a stationary datum. A second measuring device is provided which measures the deformation of the elastic connector connecting the probe to the carriage.
    Type: Grant
    Filed: January 10, 1989
    Date of Patent: November 26, 1991
    Assignee: Commonwealth Scientific and Industrial Research Organization
    Inventor: John S. Field