Patents by Inventor Raghavan Krishnaswamy

Raghavan Krishnaswamy 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: 6175097
    Abstract: A guide pin comprising a metal core and a generally smooth, non-porous insulative ceramic layer disposed on the metal core. An intermediate layer comprising titanium-carbonitride (TiCN) may be disposed on the metal core, thereby improving bonding of the ceramic layer to the guide pin assembly. In an important feature, the insulative layer is generally nonporous and has high hardness, and thus exhibits excellent wear resistance. The intermediate and insulative layers are deposited by a chemical vapor deposition process known as the “Bernex” process that results in a very hard, generally nonporous coating.
    Type: Grant
    Filed: March 11, 1999
    Date of Patent: January 16, 2001
    Inventors: Srimathy Raghavan, Raghavan Krishnaswamy
  • Patent number: 6086953
    Abstract: A method for manufacturing a guide pin is disclosed, which comprises machining a metal substrate core; optionally depositing an intermediate coating onto the substrate core; and depositing an insulative ceramic coating onto the intermediate coating by a chemical vapor deposition process under pressure conditions of up to about 500 torr, wherein the Rockwell C hardness of the metal core is greater than or equal to about 45, and the surface roughness values of the as-deposited coating are Ra less than or equal to about 35 microinches and Rmax less than or equal to about 250 microinches.
    Type: Grant
    Filed: March 12, 1999
    Date of Patent: July 11, 2000
    Inventors: Srimathy Raghavan, Raghavan Krishnaswamy
  • Patent number: 5925412
    Abstract: A method for manufacturing a guide pin is disclosed, which comprises maching a metal substrate core; and depositing an insulative ceramic coating by the Bernex chemical vapor deposition process, wherein the Rockwell C hardness of the metal core is greater than or equal to about 45, and the surface roughness value of the as-deposited coating are Ra less than or equal to about 35 microinches and Rmax less than or equal to about 250 microinches.
    Type: Grant
    Filed: July 25, 1997
    Date of Patent: July 20, 1999
    Inventors: Srimathy Raghavan, Raghavan Krishnaswamy