Patents by Inventor Derek J. Clark

Derek J. Clark 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: 4785303
    Abstract: An omni-directional aerial, more especially for the reception of domestic television programs in the U.H.F. band, comprises four folded dipole elements (1-4), each formed as a self-supporting open-ended wire loop (1A, 1B, 1C, 1D) integral with twin feeder portions (1E, 1F; 2E, 2F; 3E, 3F; 4E, 4F). The loops are arranged in planes parallel to a common central axis and are regularly angularly displaced about this axis so that opposed pairs of loops lie in parallel planes. The twin feeder portions (1E, 1F; 2E,2F; 3E,3F; 4E,4F) are connected in common to respective terminal means at the central axis, and each pair of feeder portions of each loop extend parallel to one another in a plane radial to the central axis which enables simple matching of the impedance of the aerial to a connecting cable.
    Type: Grant
    Filed: October 3, 1986
    Date of Patent: November 15, 1988
    Assignee: Maxview Aerials Limited
    Inventors: Reginald E. J. Clark, Derek J. Clark
  • Patent number: 4134319
    Abstract: Apparatus for punching regularly-spaced apertures in film or tape includes a rotary ring carrying a plurality of radially-extending punches, a further rotary ring carrying a plurality of dies and a drive ring outwardly of the punch-carrying ring which is mounted eccentrically of the punch-carrying ring and serves to force the punches at a punching zone into corresponding dies and thereby punches the required apertures in the film or tape.To avoid damage to the surfaces of the film or tape infeed and outfeed guides are provided for directing the film along an in-feed path initially parallel to the axis of rotation of the punch ring and turning the film or tape about one of the guides rotatable about an axis approximately 17.degree. to the horizontal and in a plane at right angles to the axis of rotation of the punch ring. The out-feed guide is rotatable about a similarly inclined axis.
    Type: Grant
    Filed: November 3, 1977
    Date of Patent: January 16, 1979
    Assignee: Racal-Zonal Limited
    Inventor: Derek J. Clark