Patents by Inventor Teddy J. Hammack

Teddy J. Hammack 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).

  • Self regulating heating device employing positive temperature coefficient of resistance compositions
    Patent number: 4658121
    Abstract: Disclosed is a positive temperature coefficient of resistance (PTC) crosslinked polymeric composition comprising a first polymeric material exhibiting high green strength prior to crosslinking and elastomeric behavior subsequent to cross-linking, and a second polymeric material comprising a thermoplastic, both said materials having dispersed therein conductive particles, e.g., carbon black, and further, said composition exhibiting a rise in resistance with increased temperature at temperatures above the melting point of either material.
    Type: Grant
    Filed: August 29, 1985
    Date of Patent: April 14, 1987
    Assignee: Raychem Corporation
    Inventors: David A. Horsma, Teddy J. Hammack
  • Positive temperature coefficient of resistance compositions
    Patent number: 4560498
    Abstract: Disclosed is a positive temperature coefficient of resistance (PTC) crosslinked polymeric composition comprising a first polymeric material exhibiting high green strength prior to crosslinking and elastomeric behavior subsequent to cross-linking, and a second polymeric material comprising a thermoplastic, both said materials having dispersed therein conductive particles, e.g., carbon black, and further, said composition exhibiting a rise in resistance with increased temperature at temperatures above the melting point of either material.
    Type: Grant
    Filed: October 12, 1979
    Date of Patent: December 24, 1985
    Assignee: Raychem Corporation
    Inventors: David A. Horsma, Teddy J. Hammack