Patents by Inventor Paul N-J. Liang

Paul N-J. Liang 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).

  • Quantitative method for evaluation of the state of piano hammer felt tonal regulation
    Patent number: 5537862
    Abstract: A method for measuring dynamic hardness of elastic materials is applied particularly to determining the state of tonal quality for a piano hammer. The method includes selecting a piano hammer of predetermined type from a set of piano hammers, causing the selected piano hammer to strike against an impact surface having the form of a piano string or string grouping appropriate to a piano hammer of the predetermined type, measuring one or more elements of force and motion of the piano hammer striking the impact surface, e.g. force, determining, e.g., the cut-off frequency of the power spectrum for the selected piano hammer striking upon the impact surface, and comparing the determined cut-off frequency of the power spectrum for the selected piano hammer against a predetermined range of cut-off frequencies of power spectrum acceptable for piano hammer of the predetermined type. An apparatus for testing is also described.
    Type: Grant
    Filed: November 1, 1994
    Date of Patent: July 23, 1996
    Assignee: Rensselaer Polytechnic Institute
    Inventors: Henry A. Scarton, Warren C. Kennedy, John F. Yungman, Paul N-J. Liang
  • Quantitative method for evaluation of the state of piano hammer felt tonal regulation
    Patent number: 5423241
    Abstract: A method for measuring dynamic hardness of elastic materials is applied particularly to determining the state of tonal quality for a piano hammer. The method includes selecting a piano hammer of predetermined type from a set of piano hammers, causing the selected piano hammer to strike against an impact surface having the form of a piano string or string grouping appropriate to a piano hammer of the predetermined type, measuring one or more elements of force and motion of the piano hammer striking the impact surface, e.g. force, determining, e.g., the cut-off frequency of the power spectrum for the selected piano hammer striking upon the impact surface, and comparing the determined cut-off frequency of the power spectrum for the selected piano hammer against a predetermined range of cut-off frequencies of power spectrum acceptable for piano hammer of the predetermined type. An apparatus for testing is also described.
    Type: Grant
    Filed: October 5, 1992
    Date of Patent: June 13, 1995
    Assignee: Rensselaer Polytechnic Institute
    Inventors: Henry A. Scarton, Warren C. Kennedy, John F. Yungman, Paul N-J. Liang