Patents by Inventor Edward V. Fritsch

Edward V. Fritsch 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).

  • Shock absorbing bit retaining ring
    Patent number: 4924948
    Abstract: A percussion tool assembly, such as a rock drill assembly, with a new and useful split retaining ring for maintaining the drill bit in the drill assembly. The split retaining ring has a Belleville spring-like profile to enable the split retaining ring to deflect resiliently when the drill bit is driven into engagement with the split retaining ring. The split retaining ring functions as a conventional retaining ring and also as a shock absorber to absorb surplus energy not completely used in the drilling of rock or other strata.
    Type: Grant
    Filed: November 15, 1988
    Date of Patent: May 15, 1990
    Assignee: Sandvik Rock Tools, Inc.
    Inventors: Jo-Yu Chuang, Edward V. Fritsch