Patents by Inventor William E. Griffiths

William E. Griffiths 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: 4335611
    Abstract: An accelerometer comprises an electric coil pivotally mounted in a magnetic field about an axis extending perpendicular to the field for oscillatory movement substantially perpendicular to the field, in the manner of a D'Arsonval movement. Switching means in the form of a radition source and detector responds to movement of the coil assembly when on either side of a switching position to apply a constant current to the coil to move it in the direction of the switching position, thereby setting up an oscillation of the coil. Linear acceleration is measured by having an inertial mass, such as provided by mounting the coil away from its center of mass, displaced from the pivotal axis. An acceleration force acting on the mass of the oscillating coil alters the proportion of time spent at each side of the switching position to give an average current flow in the coil related to the magnitude of acceleration. More than one coil may be provided to measure acceleration along a number of axes.
    Type: Grant
    Filed: May 30, 1980
    Date of Patent: June 22, 1982
    Assignee: Ferranti Limited
    Inventors: Robert S. Bennett, William E. Griffiths
  • Patent number: 4257651
    Abstract: An all-welded wire spoke wheel for a pneumatic tire includes a pneumatic tire rim formed with a relatively wide groove or depression in its inner face which extends all around the rim. An elongated metal strap is formed having a length, width and thickness approximating the circumference, width and depth of the rim groove. A series of spokes are welded endwise to that strap at spaced-apart locations therealong and then the strap is bent into a hoop with the spokes extending radially inward and seated snugly in the rim groove. After the hoop is secured to the rim at locations all around the rim, a wheel hub is welded conventionally to the radially inner ends of the spokes concentric with the rim.
    Type: Grant
    Filed: August 23, 1979
    Date of Patent: March 24, 1981
    Assignee: Hedstrom Co.
    Inventor: William E. Griffith, Jr.
  • Patent number: 4149417
    Abstract: A distance measuring arrangement has an accelerometer transducer of the force balance type in which a switch closed by the action of an acceleration force causes a constant current to flow in a coil to oppose the force and open the switch. The switch opens and closes in a repetitive cycle at the resonant frequency of the system, the closed switch gating clock pulses to integration means. The transducer may take two forms. In the first the proportion of time that the switch is closed in each cycle is proportional to the acceleration value. Distance measurement comprises counting the clock pulses to effect a first stage of integration and summating the counter totals every 1000 clock pulses to give a distance travelled signal. In the second, the proportion of time that the switch is closed in each cycle is proportional to the square root of the acceleration value and distance measuring comprises counting the clock pulses to give a signal proportional to the square root of distance travelled.
    Type: Grant
    Filed: December 5, 1977
    Date of Patent: April 17, 1979
    Assignee: Ferranti Limited
    Inventors: William E. Griffiths, Peter M. Williams