Patents by Inventor Ralph N. Daugherty

Ralph N. Daugherty 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).

  • Piezoelectric stress indicator for mine roofs
    Patent number: 4127788
    Abstract: A device for detecting deformations in mine roofs wherein an open cylindrical casing having inner and outer threaded surfaces is threaded into the mine roof. A piezoelectric crystal is mounted within the casing to sense the deformations and stresses in the mine roof. Provision is made for mounting a plurality of piezoelectric crystals within the casing whereby stresses at varying locations are sensible.
    Type: Grant
    Filed: July 8, 1977
    Date of Patent: November 28, 1978
    Inventor: Ralph N. Daugherty