Patents by Inventor Norwood H. Andrews

Norwood H. Andrews 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: 4664319
    Abstract: Improved grinding in a re-entrant jet comminuting and classifying mill is provided by directing the gaseous jet streams emitted from the nozzles in the annular peripheral wall of the mill's vortex chamber at a relatively acute angle to the radius of the chamber and also at an acute angle to the central axis of the chamber whereby the jet streams merge at a tangent circle that is substantially within the midpoint of the radius of the chamber and axially spaced from the plane of the nozzles in a direction remote from the axial outlet of the mill. The mill is provided with axial feed.
    Type: Grant
    Filed: September 24, 1984
    Date of Patent: May 12, 1987
    Assignee: Norandy, Incorporated
    Inventor: Norwood H. Andrews
  • Patent number: 4504017
    Abstract: Apparatus for comminuting materials to extremely fine size includes a circulating stream jet mill and a discrete but functionally interconnected and interdependent rotating anvil-jet impact mill. New material is injected into the impact mill against a rotor, and the partly comminuted material is transferred to the jet mill with vortex feed into the jet mill. Uncomminuted material in the jet mill is reinjected into the impact mill. The two mills transfer the material back and forth until the particles are comminuted, classified, and removed from the jet mill. The anvil-jet mill is provided with stationary anvils and support for turning the rotor at increased velocity.
    Type: Grant
    Filed: June 8, 1983
    Date of Patent: March 12, 1985
    Assignee: Norandy, Incorporated
    Inventor: Norwood H. Andrews
  • Patent number: 4248387
    Abstract: A re-entrant circulating stream mill vents a part of the circulating stream adjacent the annular peripheral wall of the mill directly to the junction in each of a plurality of sets of pressure nozzles and cooperating acceleration tubes which are used to form the circulating stream. Each pressure nozzle provides a high velocity gaseous jet stream that entrains material as it enters the acceleration tube where the material is accelerated to its maximum velocity before it is discharged into the vortex chamber of the mill and impacts upon the circulating stream adjacent the annular peripheral wall of the vortex chamber. The apparatus also takes advantage of the comminution of the material which takes place in the acceleration tube.
    Type: Grant
    Filed: May 9, 1979
    Date of Patent: February 3, 1981
    Assignee: Norandy, Inc.
    Inventor: Norwood H. Andrews
  • Patent number: 4189102
    Abstract: Comminuting and classifying apparatus of the re-entrant circulating stream jet type includes a vortex chamber and jet means. The feed means includes a central conical recess in one wall of the chamber, a coaxial circular chamber opening into said recess and means to direct the material and gaseous carrier fluid into said chamber tangential to the wall of the chamber so that the material and carrier fluid is added to the vortex with a rotative velocity. The apparatus may also be provided with means for jet and anvil comminution of feed material and/or recirculating material. The chamber may include an annular shoulder for skimming undesirable particles in the feed material.
    Type: Grant
    Filed: May 10, 1978
    Date of Patent: February 19, 1980
    Inventor: Norwood H. Andrews
  • Patent number: 4018388
    Abstract: A jet-type grinding mill having a circular chamber wherein a rotating vortex is formed by gaseous fluid injected into the chamber, the material to be ground being fed into the mill through a feed means at the center of the vortex, there being a central recess at the bottom of the chamber below the feed inlet which has upwardly inclined walls to direct the fed particles upwardly and outwardly into the vortex.
    Type: Grant
    Filed: May 13, 1976
    Date of Patent: April 19, 1977
    Inventor: Norwood H. Andrews
  • Patent number: 3986271
    Abstract: An apparatus for partially drying and feeding material from an external source into a drying mill is disclosed. A conduit comprising first and second wall members and having an annular cross-section substantially throughout its acial length is connected to one end of a receiving chamber. Means are provided for guiding the material to be dried from an external source into a receiving chamber and for depositing the material in an area within the receiving chamber which is substantially coaxial with the conduit. Hot gases are introduced into the receiving chamber and propelled into and along the annular conduit with a generally circumferentially cyclonic flow. As the gas proceeds through the conduit, it carries with it the material deposited in the receiving chamber and feeds it into a drying mill.
    Type: Grant
    Filed: May 21, 1975
    Date of Patent: October 19, 1976
    Inventor: Norwood H. Andrews