Patents by Inventor Paul G. Wall

Paul G. Wall 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: 4879939
    Abstract: An action for an upright piano which emulates or simulates the action of a grand piano is provided. In the action, a back check lever is positioned above the back of the key, and a grand piano whippen is positioned above the back check lever. The grand whippen acts on a knuckle provided on a catcher arm integrally connected with the hammer shank at a substantial angle. Depression of the key produces upward movement of the back of the key, the back check lever, and the grand whippen, in turn producing rotation of the catcher arm which drives the hammer towards the string. The catcher arm has a catcher at its forward end and the back check lever has a back check for catching the catcher after the hammer has rebounded from the string. A vertically-acting gravity-activated damping action is provided. The hammer action is mounted independently from the damping action, and a shifting lever connected to a foot pedal permits lateral shifting of the hammer action with respect to the strings.
    Type: Grant
    Filed: March 22, 1988
    Date of Patent: November 14, 1989
    Inventor: Paul G. Wall