Patents by Inventor David A. Leeman

David A. Leeman 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: 11834790
    Abstract: A self-compensating tube assembly is disclosed for use in a doctor blade holder. The self-compensating tube assembly includes a tube including a membrane that encloses a liquid with a substantially invariable bulk modulus of elasticity, density and viscosity; and chatter responsive for providing any of monitoring means of blade chatter through pressure, damping of blade chatter, and minimizing blade chatter.
    Type: Grant
    Filed: April 15, 2022
    Date of Patent: December 5, 2023
    Assignee: Kadant Inc.
    Inventors: Robert P. Johnson, David Leeman, Allen Brauns
  • Patent number: 9518359
    Abstract: The invention provides a doctor blade holder system that includes a doctor blade support structure, an adjustment profiling plate, and a series of adjustment mechanisms. The doctor blade support structure includes an elongated slot for receiving a doctor blade and a separate elongated slot to house mounting hardware. The adjustable profiling plate causes pressure to be applied to the working blade in a continuous manner along the length of the working blade, wherein the profiling plate is mounted to a holder mounting plate with a series of pairs of mounting structures allowing unconstrained flexure, or rotation, of the profiling plate with respect to holder mounting plate around two axes. The series of adjustment mechanisms attach to the holder mounting plate and acting on the profiling plate, wherein the adjustment mechanisms are capable of displacing the profiling plate in a bi-directional manner.
    Type: Grant
    Filed: November 6, 2014
    Date of Patent: December 13, 2016
    Assignee: Kadant, Inc.
    Inventors: Allen Brauns, David Leeman, Robert Johnson
  • Publication number: 20150122444
    Abstract: The invention provides a doctor blade holder system that includes a doctor blade support structure, an adjustment profiling plate, and a series of adjustment mechanisms. The doctor blade support structure includes an elongated slot for receiving a doctor blade and a separate elongated slot to house mounting hardware. The adjustable profiling plate causes pressure to be applied to the working blade in a continuous manner along the length of the working blade, wherein the profiling plate is mounted to a holder mounting plate with a series of pairs of mounting structures allowing unconstrained flexure, or rotation, of the profiling plate with respect to holder mounting plate around two axes. The series of adjustment mechanisms attach to the holder mounting plate and acting on the profiling plate, wherein the adjustment mechanisms are capable of displacing the profiling plate in a bi-directional manner.
    Type: Application
    Filed: November 6, 2014
    Publication date: May 7, 2015
    Inventors: Allen Brauns, David Leeman, Robert Johnson
  • Publication number: 20150075928
    Abstract: A self-compensating tube assembly is disclosed for use in a doctor blade holder. The self-compensating tube assembly includes a tube including a membrane that encloses a liquid with a substantially invariable bulk modulus of elasticity, density and viscosity; and chatter responsive for providing any of monitoring means of blade chatter through pressure, damping of blade chatter, and minimizing blade chatter.
    Type: Application
    Filed: April 28, 2014
    Publication date: March 19, 2015
    Applicant: Kadant Inc.
    Inventors: Robert P. Johnson, David Leeman, Allen Brauns
  • Patent number: 8898851
    Abstract: A doctor blade holder system is disclosed that includes a doctor blade holder that includes a doctor blade receiving region for receiving a doctor blade, and an actuation system for causing the doctor blade receiving region to be selectively moved toward or away from a roll surface by rotating the doctor blade holder about a first axis, wherein the doctor blade holder system is generally circular shaped in cross-sectional area and wherein the first axis is generally centrally locate with the generally circular cross-sectional area.
    Type: Grant
    Filed: December 9, 2011
    Date of Patent: December 2, 2014
    Assignee: Kadant, Inc.
    Inventors: David Leeman, Allen Brauns, Robert Johnson
  • Patent number: 8337667
    Abstract: A doctoring system is disclosed for cleaning a moving surface in a papermaking machine, and the doctoring system includes a doctor blade and fluid assist system. The doctor blade is coupled to a doctor blade holder, and the doctor blade holder is coupled to a doctor-back. The fluid assist system is for providing a fluid under positive pressure that is higher than atmospheric pressure. The fluid is directed in a direction generally opposite a direction of movement of the moving surface such that fluid of high momentum is provided to impinge on water resident within the moving surface and adjacent a leading edge of the doctor blade during movement of the moving surface.
    Type: Grant
    Filed: January 25, 2010
    Date of Patent: December 25, 2012
    Assignee: Kadant, Inc.
    Inventors: Robert P. Johnson, David Leeman, Allen J. Brauns
  • Patent number: 8337666
    Abstract: A doctoring system is disclosed for a papermaking machine wherein the doctoring system includes a doctor blade and a fluid assist means. The doctor blade is coupled to a doctor blade holder, and is for cleaning a moving surface. The doctor blade holder is coupled to a doctor-back. The fluid assist means is for providing a fluid under positive pressure that is higher than atmospheric pressure and is directed in a direction generally along a direction of movement of the moving surface such that a negative pressure that is lower than atmospheric pressure develops in a negative pressure zone adjacent the moving surface and a following surface of the doctor blade during movement of the moving surface.
    Type: Grant
    Filed: January 25, 2010
    Date of Patent: December 25, 2012
    Assignee: Kadant, Inc.
    Inventors: Robert P. Johnson, David Leeman, Allen J. Brauns
  • Patent number: 8321992
    Abstract: A doctor blade holder is disclosed that includes first and second members as well as position adjustment means. The first member includes a plurality of first member mounting structures that are integrally formed with the first member and are mutually spaced apart from one another along an elongated direction that is parallel with an elongated edge of a doctor blade. The second member is coupled to the first member, at least in part, by a plurality of second member mounting structures that are mutually spaced apart from one another along the elongated direction that is parallel with the elongated edge of the doctor blade. The position adjustment means is for adjusting the relative positions of the first member and the second member while the first member is coupled to the second member, at least in part, by the plurality of first member mounting structures and the plurality of second member mounting structures.
    Type: Grant
    Filed: December 3, 2008
    Date of Patent: December 4, 2012
    Assignee: Kadant Web Systems, Inc.
    Inventors: Royal Gauvin, David Leeman
  • Publication number: 20120167330
    Abstract: A doctor blade holder system is disclosed that includes a doctor blade holder that includes a doctor blade receiving region for receiving a doctor blade, and an actuation system for causing the doctor blade receiving region to be selectively moved toward or away from a roll surface by rotating the doctor blade holder about a first axis, wherein the doctor blade holder system is generally circular shaped in cross-sectional area and wherein the first axis is generally centrally locate with the generally circular cross-sectional area.
    Type: Application
    Filed: December 9, 2011
    Publication date: July 5, 2012
    Applicant: KADANT INC.
    Inventors: David Leeman, Allen Brauns, Robert Johnson
  • Publication number: 20110026993
    Abstract: A doctor blade holder is disclosed that includes a first member, a second member position adjustment elements, and fluid assisted cleaning elements. The first member includes an elongated edge that is adapted for receiving a doctor blade, and the second member is movably coupled to the first member. The second member is secured to a doctor back. The position adjustment elements are for adjusting the relative position of the first member and the second member. The fluid assisted cleaning elements are for providing pressurized fluid to an area near an elongated edge of the doctor blade. The fluid assisted cleaning elements include at least one plenum within the first member.
    Type: Application
    Filed: August 11, 2010
    Publication date: February 3, 2011
    Applicant: KADANT INC.
    Inventors: David Leeman, Royal Gauvin
  • Patent number: 7867364
    Abstract: A doctor assembly is disclosed for use in a paper-making machine. The doctor assembly includes a doctor blade holder into which a doctor blade may be inserted and the doctor blade holder includes a pressure plate, pressure adjustment system, a support tray, and a bracket in accordance with an embodiment. The pressure plate is for supporting and aligning the doctor blade in a cross machine direction for application to a machine roll. The pressure adjustment system is for adjusting the pressure applied to the machine roll by the doctor blade, said pressure adjustment means including at least one fluid reservoir having a wall that contacts the pressure plate. The support tray for supporting the at least one fluid reservoir, and the support tray includes at least one bracket alignment feature. The bracket is attached to the support tray for pivotal attachment to the pressure plate.
    Type: Grant
    Filed: August 14, 2007
    Date of Patent: January 11, 2011
    Assignee: Kadant Inc.
    Inventors: David Leeman, Royal Gauvin
  • Publication number: 20100200187
    Abstract: A doctoring system is disclosed for a papermaking machine wherein the doctoring system includes a doctor blade and a fluid assist means. The doctor blade is coupled to a doctor blade holder, and is for cleaning a moving surface. The doctor blade holder is coupled to a doctor-back. The fluid assist means is for providing a fluid under positive pressure that is higher than atmospheric pressure and is directed in a direction generally along a direction of movement of the moving surface such that a negative pressure that is lower than atmospheric pressure develops in a negative pressure zone adjacent the moving surface and a following surface of the doctor blade during movement of the moving surface.
    Type: Application
    Filed: January 25, 2010
    Publication date: August 12, 2010
    Inventors: Robert P. Johnson, David Leeman, Allen J. Brauns
  • Publication number: 20100186770
    Abstract: A doctoring system is disclosed for cleaning a moving surface in a papermaking machine, and the doctoring system includes a doctor blade and fluid assist system. The doctor blade is coupled to a doctor blade holder, and the doctor blade holder is coupled to a doctor-back. The fluid assist system is for providing a fluid under positive pressure that is higher than atmospheric pressure. The fluid is directed in a direction generally opposite a direction of movement of the moving surface such that fluid of high momentum is provided to impinge on water resident within the moving surface and adjacent a leading edge of the doctor blade during movement of the moving surface.
    Type: Application
    Filed: January 25, 2010
    Publication date: July 29, 2010
    Inventors: Robert P. Johnson, David Leeman, Allen J. Brauns
  • Publication number: 20090148208
    Abstract: A doctor blade holder is disclosed that includes first and second members as well as position adjustment means. The first member includes a plurality of first member mounting structures that are integrally formed with the first member and are mutually spaced apart from one another along an elongated direction that is parallel with an elongated edge of a doctor blade. The second member is coupled to the first member, at least in part, by a plurality of second member mounting structures that are mutually spaced apart from one another along the elongated direction that is parallel with the elongated edge of the doctor blade. The position adjustment means is for adjusting the relative positions of the first member and the second member while the first member is coupled to the second member, at least in part, by the plurality of first member mounting structures and the plurality of second member mounting structures.
    Type: Application
    Filed: December 3, 2008
    Publication date: June 11, 2009
    Applicant: KADANT WEB SYSTEMS, INC.
    Inventors: Royal Gauvin, David Leeman
  • Publication number: 20080190579
    Abstract: A doctor assembly is disclosed for use in a paper-making machine. The doctor assembly includes a doctor blade holder into which a doctor blade may be inserted and the doctor blade holder includes a pressure plate, pressure adjustment system, a support tray, and a bracket in accordance with an embodiment. The pressure plate is for supporting and aligning the doctor blade in a cross machine direction for application to a machine roll. The pressure adjustment system is for adjusting the pressure applied to the machine roll by the doctor blade, said pressure adjustment means including at least one fluid reservoir having a wall that contacts the pressure plate. The support tray for supporting the at least one fluid reservoir, and the support tray includes at least one bracket alignment feature. The bracket is attached to the support tray for pivotal attachment to the pressure plate.
    Type: Application
    Filed: August 14, 2007
    Publication date: August 14, 2008
    Applicant: KADANT WEB SYSTEMS, INC.
    Inventors: David Leeman, Royal Gauvin
  • Patent number: 6758996
    Abstract: Granulated papermaking sludge is combined with plastic to form composite materials that may be shaped into structural and non-structural articles.
    Type: Grant
    Filed: July 13, 2001
    Date of Patent: July 6, 2004
    Assignee: Kadant Composites Inc.
    Inventors: Yiannis A. Monovoukas, Steven J. Anderson, David Leeman, Anatole A. Klyosov, George P. Philippidis
  • Publication number: 20030030176
    Abstract: Granulated papermaking sludge is combined with plastic to form composite materials that may be shaped into structural and non-structural articles.
    Type: Application
    Filed: July 13, 2001
    Publication date: February 13, 2003
    Inventors: Yiannis A. Monovoukas, Steven J. Anderson, David Leeman, Anatole A. Klyosov, George P. Philippidis
  • Patent number: 5783042
    Abstract: A method and system of measuring deflected doctor blade angle and loading force of an arrangement including a doctor apparatus operating in connection with a rotating cylinder, the apparatus having a doctor blade and a support member which pivots about at least one pivot point in response to an externally applied force for applying the doctor blade to a contact point on the cylinder. The arrangement corresponds to a kinematic model of linkages including a first link defined between the at least one pivot point and the contact point, a second link defined between the contact point and the center of the cylinder, and a third link defined between the center of the cylinder and the at least one pivot point.
    Type: Grant
    Filed: December 6, 1995
    Date of Patent: July 21, 1998
    Assignee: Thermo Web Systems, Inc.
    Inventors: David A. Leeman, Steven J. Coleman, David J. Dziadzio, William K. Giguere, Ronald F. Goodnow
  • Patent number: 5303484
    Abstract: A convective dryer for drying a moving coated web has at least one module arranged on one side of the path of web travel. The module includes a housing subdivided into a first chamber opening towards the path of web travel and a second adjacent enclosed chamber. Mutually spaced nozzle assemblies extend laterally across the path of web travel within the first chamber. The nozzle assemblies are connected by a supply duct to air heating and recirculating components in the second chamber. The supply duct gradually diverges in width from a narrow inlet section communicating with the second chamber to a widened delivery end communicating with the nozzle assemblies at the approximate center of the path of web travel.
    Type: Grant
    Filed: April 9, 1992
    Date of Patent: April 19, 1994
    Assignee: Thermo Electron Web Systems, Inc.
    Inventors: Kenneth G. Hagen, David A. Leeman