Patents by Inventor Leonard K. John

Leonard K. John 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: 4408516
    Abstract: A violin is constructed with an acoustic box formed of composite materials, sheets of unidirectional graphite fibre in a resin matrix. The soundboard is constructed of paired sheets of the composite material overlaid and bonded with the sheets symmetrically placed. The fibres of a first pair of sheets are aligned with the longitudinal axis of the soundboard to transmit vibrations through the full length of the soundboard. The fibres of a second pair of sheets are oriented perpendicular to the longitudinal axis to provide structural strength in a perpendicular direction. The fibres of a third pair of sheets are oriented at an acute angle to the longitudinal axis, fibres of one sheet oriented at about 45 degrees to the axis, and those of the other sheet at about minus 45 degrees. The third pair provides torsional rigidity, and provides additional stiffness in the longitudinal direction, thereby affecting the tonal qualities of the violin.
    Type: Grant
    Filed: August 24, 1981
    Date of Patent: October 11, 1983
    Inventor: Leonard K. John