Patents by Inventor Willard L. Johnson

Willard L. Johnson 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: 4966718
    Abstract: The cross flow filter method includes an open tank having a first liquid retaining section, a second filter retaining section and a third solids collecting section in fluid communication with each other. A filter assembly is retained within the second section and includes a filter panel having a generally vertically disposed porous media surface. Filtrate is removed by applying very low vacuum pressure in communication with the filter panel such that filtrate is drawn through the pores of the filter media surface at a flow rate Q.sub.out. Fluid to be filtered is simultaneously cross flowing vertically downward across the filter media surface at a flow rate Q.sub.x, such that the horizontal velocity V.sub.h of fluid drawn through the filter media surface is very slight with respect to the vertical velocity V.sub.v of the cross flowing unfiltered fluid.
    Type: Grant
    Filed: March 13, 1989
    Date of Patent: October 30, 1990
    Inventor: Willard L. Johnson
  • Patent number: 4964987
    Abstract: A cross flow filter apparatus and method uses an open tank having a first liquid retaining section, a second filter retaining section and a third solids collecting section in fluid communication with each other. A filter assembly is retained within the second section and includes a filter panel having a generally vertically disposed filter membrane surface, preferably with submicron pores. Filtrate is removed by applying low vacuum pressure, in the range of about 5 inches vacuum pressure (Mercury), in communication with the filter panel such that filtrate is drawn through the pores of the filter membrane surface at a flow rate Q.sub.out. Fluid to be filtered is cross flowing vertically downward across the filter membrane surface at a flow rate Q.sub.x, such that the horizontal velocity V.sub.h of fluid drawn through the filter membrane surface is less than the vertical velocity V.sub.v of the cross flowing unfiltered fluid.
    Type: Grant
    Filed: June 10, 1988
    Date of Patent: October 23, 1990
    Inventor: Willard L. Johnson
  • Patent number: 4919805
    Abstract: A system for continuously or periodically flushing collected particles from filter leaf assemblies without interrupting the filtering operation is disclosed. The filter leaf assemblies are constructed from a pair of like grid-like filter media support panels mounted in spaced parallel relationship within a rigid rectangular peripheral frame. Sheets of filter media overlie the outer surfaces of the support panels and are fixedly sealed to the frame around the entire periphery of the panel. One side of the frame is fixedly mounted to an outlet pipe whose interior communicates with the space between the support panels via mating slots in the pipe wall and frame. Two filter media attachment arrangements and two frame to pipe mounting arrangements are disclosed.
    Type: Grant
    Filed: June 3, 1988
    Date of Patent: April 24, 1990
    Inventor: Willard L. Johnson
  • Patent number: 4859332
    Abstract: A filter leaf cleaning system for use in a suction-type filter apparatus having a tank to receive polluted liquids to be filtered or clarified includes a cleaning system header connected to a filtrate discharge conduit for diverting a portion of filtrate flow into the cleaning system, valve means connected to the cleaning system header for controlling filtrate flow into the cleaning system, a dispersing conduit connected to the cleaning system header adjacent a particulate-filtering surface of each filter leaf and having an opening for directing the filtrate flow across the particulate-filtering surface to flush particulates from the surface toward a solids collecting section of the tank housing the filter leaf. In addition, or in the alternative, the cleaning system may employ a membrane wiping member for sweeping movement across the particulate-filtering surface to brush residue or particulates from the surface.
    Type: Grant
    Filed: November 19, 1987
    Date of Patent: August 22, 1989
    Inventor: Willard L. Johnson
  • Patent number: 4790935
    Abstract: Improved filter leaf assemblies are constructed from a pair of like grid-like filter media support panels mounted in spaced parallel relationship within a rigid rectangular peripheral frame. Sheets of filter media overlie the outer surfaces of the support panels and are fixedly sealed to the frame around the entire periphery of the panel. One side of the frame is fixedly mounted to an outlet pipe whose interior communicates with the space between the support panels via mating slots in the pipe wall and frame. Two filter media attachment arrangements and two frame to pipe mounting arrangements are disclosed.
    Type: Grant
    Filed: November 26, 1986
    Date of Patent: December 13, 1988
    Inventor: Willard L. Johnson
  • Patent number: 4579656
    Abstract: A leaf-type filter system in which a suction pump is employed to pump filtered fluid from a series of individual filter leaves is connected to the individual leaf chambers via fluid couplings located above the surface of fluid being filtered. The couplings are of inverted U-shape and have a sliding sealing fit with the vertical outlet tube of a leaf and a vertical receiving tube mounted in a manifold or header external of the main filter tank.
    Type: Grant
    Filed: January 28, 1985
    Date of Patent: April 1, 1986
    Inventor: Willard L. Johnson
  • Patent number: 4519903
    Abstract: In a suction-type filter machine, a plurality of filter leaves each haing a core panel of egg-crate type walls defining transverse passageways through said panel and openings through said walls to provide vertical, horizontal and longitudinal passageways for filtrate flow drawn by a suction pump through the filter medium enwrapping the core panel and a conduit conductor enclosing an edge portion of the core panel.
    Type: Grant
    Filed: January 24, 1983
    Date of Patent: May 28, 1985
    Inventor: Willard L. Johnson
  • Patent number: 4176709
    Abstract: A stack-type heat exchanger having a complementary fan section in attached communication with a heat exchanger tube section, the fan section forcing incoming air through heat exchanger tubes having a damper plate at or adjacent their output ends to generate a positive air pressure in the tubes at a value above and in excess of the pressure of vented stack gases passing through the heat exchanger tube section chamber from and to lower and upper portions of said stack.
    Type: Grant
    Filed: February 6, 1978
    Date of Patent: December 4, 1979
    Inventor: Willard L. Johnson