Patents by Inventor David A. Lockhart

David A. Lockhart 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).

  • Coil wound spacer
    Patent number: 4303362
    Abstract: Spacers are used where added bolt length is advantageous. Such spacers are usually one piece and are formed from tubing having a solid cylindrical wall which often splits or yields when stressed by highly torqued bolts. An improved spacer (10) is formed from wound coil (12) to form a spiral walled cylindrical body (20) having advantageous over prior spacers. Each spiral (14) includes a portion (26) which abuts each adjacent spiral (14) and a portion (30) which is free of such abutment.
    Type: Grant
    Filed: April 23, 1979
    Date of Patent: December 1, 1981
    Assignee: Caterpillar Tractor Co.
    Inventor: David A. Lockhart
  • Method for making laminated spacer plate for engines
    Patent number: 4300273
    Abstract: A laminated spacer plate (10) for engines, pumps and the like comprises a plurality of metallic sheets (11-14), each having openings (15,16,17,24,40) preformed therethrough and secured together. The preforming of the openings through the individual sheets facilitates intercommunication of certain of the openings with passages formed within the spacer plate and eliminates the need for costly machining and related manufacturing operations normally required for the fabrication of a one-piece spacer plate.
    Type: Grant
    Filed: November 19, 1979
    Date of Patent: November 17, 1981
    Assignee: Caterpillar Tractor Co.
    Inventor: David A. Lockhart
  • Laminated spacer plate for engines and method for making the same
    Patent number: 4211205
    Abstract: A laminated spacer plate (10) for engines, pumps and the like comprises a plurality of metallic sheets (11-14), each having openings (15, 16, 17, 24, 40) preformed therethrough and secured together. The preforming of the openings through the individual sheets facilitates intercommunication of certain of the openings with passages formed within the spacer plate and eliminates the need for costly machining and related manufacturing operations normally required for the fabrication of a one-piece spacer plate.
    Type: Grant
    Filed: October 26, 1978
    Date of Patent: July 8, 1980
    Assignee: Caterpillar Tractor Co.
    Inventor: David A. Lockhart