Patents by Inventor John Caldwell

John Caldwell 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).

  • High speed particle sorter using a field emission electrode
    Patent number: 4097373
    Abstract: The present invention sorts small particles by subjecting them to a charging and motivating field produced by a single electrode. The magnitude of the charge placed on the particle passing the electrode is a controlled function of observed particle parameters. The amount of charge placed on the small particle in this manner determines the amount of deflection imparted to the particle's trajectory. Once the particle has been deflected in accordance with its observed parameter, the particle may be collected for further study. It will be appreciated that this version of the present invention deflects the small particle by applying a force to it at some angle to its direction of movement. The particle's movement will generally be impelled by the accelerative force of the fluid stream along a line between the end of a droplet producing nozzle and a collection station.
    Type: Grant
    Filed: March 23, 1977
    Date of Patent: June 27, 1978
    Inventor: John Caldwell Allred
  • Chair
    Patent number: D339928
    Type: Grant
    Filed: May 23, 1991
    Date of Patent: October 5, 1993
    Inventor: John Caldwell
  • Chair
    Patent number: D340143
    Type: Grant
    Filed: May 23, 1991
    Date of Patent: October 12, 1993
    Inventor: John Caldwell
  • Chair
    Patent number: D340146
    Type: Grant
    Filed: May 23, 1991
    Date of Patent: October 12, 1993
    Inventor: John Caldwell
  • Chair
    Patent number: D340359
    Type: Grant
    Filed: October 18, 1991
    Date of Patent: October 19, 1993
    Assignee: Garden Source Furnishings, Incorporated
    Inventor: John Caldwell
  • Chair
    Patent number: D340364
    Type: Grant
    Filed: May 23, 1991
    Date of Patent: October 19, 1993
    Inventor: John Caldwell
  • Chair
    Patent number: D341266
    Type: Grant
    Filed: October 2, 1991
    Date of Patent: November 16, 1993
    Inventor: John Caldwell
  • Bench
    Patent number: D341267
    Type: Grant
    Filed: May 23, 1991
    Date of Patent: November 16, 1993
    Inventor: John Caldwell
  • Chair
    Patent number: D341492
    Type: Grant
    Filed: October 18, 1991
    Date of Patent: November 23, 1993
    Inventor: John Caldwell
  • Chair
    Patent number: D341496
    Type: Grant
    Filed: October 18, 1991
    Date of Patent: November 23, 1993
    Inventor: John Caldwell
  • Chair
    Patent number: D342391
    Type: Grant
    Filed: October 18, 1991
    Date of Patent: December 21, 1993
    Inventor: John Caldwell