Patents by Inventor Lawrence G. Caldwell

Lawrence G. 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).

  • Device for changing flow paths in a pneumatic conveying system
    Patent number: 5069583
    Abstract: The present invention is an apparatus for directing a fluid stream from a source tube to a selected one of a plurality of outlet tubes in fluid flow communication with the source tube. Disposed within the source tube is an elongated sleeve, the sleeve having an inlet port and a single outlet port, the inlet port being in fluid flow communication with the source tube and the outlet port. The sleeve is longitudinally movable and rotatable within the source tube for selectively closing all of the outlet tubes and directing the fluid stream to a desired one of the outlet tubes. Apparatus is provided for rotating the longitudinally moving the sleeve.
    Type: Grant
    Filed: October 26, 1990
    Date of Patent: December 3, 1991
    Inventor: Lawrence G. Caldwell
  • Pneumatic stream divider
    Patent number: 4436459
    Abstract: A primary conduit for a dilute phase particulate laden pneumatic stream is aligned with a dead pocket at the intersection of the primary conduit with secondary and tertiary conduits perpendicular to the primary conduit. The primary conduit is adjustable with respect to the dead pocket to vary the position at which the stream is directed into the dead pocket to thereby control division of the amount of particulate separated into the secondary and tertiary conduits. Thus, the ratio of particulates entering the secondary and tertiary conduits may be varied in a predetermined manner.
    Type: Grant
    Filed: April 23, 1979
    Date of Patent: March 13, 1984
    Assignee: The Ducon Company, Inc.
    Inventor: Lawrence G. Caldwell