Patents by Inventor David Grewell

David Grewell 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).

  • Publication number: 20190345369
    Abstract: The present invention relates to an adhesive comprising a thermoplastic polyacrylated glycerol polymer, water, and a cross linker that is reactive with the polyacrylated glycerol polymer. This adhesive is useful in the formation of cellulosic products including oriented strand board (OSB), particle board, oriented structural straw board, chipboard, plywood, laminated veneer lumber (LVL), pressed wood, glued laminated timber (glulam), cross-laminated timber (CLT), and other wood products. Methods of producing the adhesive and cellulosic products are also disclosed.
    Type: Application
    Filed: May 7, 2019
    Publication date: November 14, 2019
    Inventors: Eric W. COCHRAN, Nacu B. HERNANDEZ, R. Chris WILLIAMS, Michael FORRESTER, David GREWELL, Andrew BECKER, Joseph J. Marcinko
  • Patent number: 10442118
    Abstract: To better control part quality of 3D printed parts, the temperature of an extruder filament using a secondary heat source is provided. A heat source, such as an infrared heat source, can be used to heat the filament of a 3D printer to the optimum temperature that will enhance welding of the filament to a substrate that it is being printed on or to. Such an optimum temperature can be based upon, in part, the temperature of the substrate. A controller or other intelligent control can be used to receive temperature readings of the substrate and/or filament and then can adjust the temperature of the heating source to optimize the temperature of the filament to better combine the filament to the substrate.
    Type: Grant
    Filed: September 29, 2016
    Date of Patent: October 15, 2019
    Assignee: Iowa State University Research Foundation, Inc.
    Inventor: David Grewell
  • Patent number: 9988318
    Abstract: This invention relates to bio-renewable fertilizer compositions and methods of making and using the bio-renewable fertilizer compositions. In particular, the fertilizer compositions include biodegradable nutrient carriers, which have naturally derived, bio-renewable nitrogen content. The fertilizer compositions also contain biodegradable stabilizer.
    Type: Grant
    Filed: October 12, 2015
    Date of Patent: June 5, 2018
    Assignee: Iowa State University Research Foundation, Inc.
    Inventors: James Schrader, William Graves, Jr., David Grewell
  • Publication number: 20170087767
    Abstract: To better control part quality of 3D printed parts, the temperature of an extruder filament using a secondary heat source is provided. A heat source, such as an infrared heat source, can be used to heat the filament of a 3D printer to the optimum temperature that will enhance welding of the filament to a substrate that it is being printed on or to. Such an optimum temperature can be based upon, in part, the temperature of the substrate. A controller or other intelligent control can be used to receive temperature readings of the substrate and/or filament and then can adjust the temperature of the heating source to optimize the temperature of the filament to better combine the filament to the substrate.
    Type: Application
    Filed: September 29, 2016
    Publication date: March 30, 2017
    Inventor: David Grewell
  • Publication number: 20160102024
    Abstract: This invention relates to bio-renewable fertilizer compositions and methods of making and using the bio-renewable fertilizer compositions. In particular, the fertilizer compositions include biodegradable nutrient carriers, which have naturally derived, bio-renewable nitrogen content. The fertilizer compositions also contain biodegradable stabilizer.
    Type: Application
    Filed: October 12, 2015
    Publication date: April 14, 2016
    Inventors: James Schrader, William Graves, JR., David Grewell
  • Patent number: 8895778
    Abstract: The invention provides energy efficient depolymerization of polyesters such as post-consumer polylactic acid. Ultrasonic induced implosions can be used to facilitate the depolymerization. The expanding market of polylactic acid-based plastic products, such as water bottles and packaging materials, has raised concerns of contaminating the recycling stream, which is largely filled with petroleum-based plastics. Thus the development of an energy efficient and economically viable PLA recycling process is urgently needed. Post consumer PLA was exposed to methanol as the suspension media in the presence of organic or ionic salts of alkali metals such a potassium carbonate and sodium hydroxide as depolymerization catalysts to provide high quality lactic acid monomers in high yield.
    Type: Grant
    Filed: January 24, 2012
    Date of Patent: November 25, 2014
    Assignee: Iowa State University Research Foundation
    Inventors: Gowrishankar Srinivasan, David Grewell
  • Publication number: 20130096342
    Abstract: The invention provides energy efficient depolymerization of polyesters such as post-consumer polylactic acid. Ultrasonic induced implosions can be used to facilitate the depolymerization. The expanding market of polylactic acid-based plastic products, such as water bottles and packaging materials, has raised concerns of contaminating the recycling stream, which is largely filled with petroleum-based plastics. Thus the development of an energy efficient and economically viable PLA recycling process is urgently needed. Post consumer PLA was exposed to methanol as the suspension media in the presence of organic or ionic salts of alkali metals such a potassium carbonate and sodium hydroxide as depolymerization catalysts to provide high quality lactic acid monomers in high yield.
    Type: Application
    Filed: January 24, 2012
    Publication date: April 18, 2013
    Inventors: Gowrishankar Srinivasan, David Grewell
  • Publication number: 20120321808
    Abstract: A coating having source from plant protein that is water insoluble and sprayable. The coating is derived from soy protein or other plants and consists of chemistries that promote water stability and insolubility in water. The spraying device for such coating is an aerosol pressure driven system or similar. The coating converts from a liquid to a solid after a length of time which can be accelerated through heating.
    Type: Application
    Filed: June 14, 2012
    Publication date: December 20, 2012
    Inventors: Roy D. Taylor, David Grewell, Maria Baboi
  • Patent number: 8172969
    Abstract: A method for ultrasonic debulking a composite laminate includes the steps of defining a path across the laminate, the path having a starting location and an ending location and applying a force to and transmitting ultrasonic vibration into the laminate along the path, beginning at the starting location and ending at the ending location. The method further includes determining a temperature of a surface of the laminate proximate to the path and varying at least one of an amplitude of the ultrasonic vibration, the applied force, a feed rate at which the force and the ultrasonic vibration are applied along the path, an angle at which the ultrasonic vibration is applied to the laminate, and an interval at which plies of the laminate are processed, based upon the determined temperature of the surface of the laminate.
    Type: Grant
    Filed: January 25, 2011
    Date of Patent: May 8, 2012
    Assignees: Textron Innovations Inc., The Ohio State University Research Foundation
    Inventors: Edward W. Lee, Avraham Benatar, David Grewell
  • Publication number: 20110114247
    Abstract: A method for ultrasonic debulking a composite laminate includes the steps of defining a path across the laminate, the path having a starting location and an ending location and applying a force to and transmitting ultrasonic vibration into the laminate along the path, beginning at the starting location and ending at the ending location. The method further includes determining a temperature of a surface of the laminate proximate to the path and varying at least one of an amplitude of the ultrasonic vibration, the applied force, a feed rate at which the force and the ultrasonic vibration are applied along the path, an angle at which the ultrasonic vibration is applied to the laminate, and an interval at which plies of the laminate are processed, based upon the determined temperature of the surface of the laminate.
    Type: Application
    Filed: January 25, 2011
    Publication date: May 19, 2011
    Inventors: Edward W. Lee, Avraham Benatar, David Grewell
  • Patent number: 7892372
    Abstract: A method for ultrasonic debulking a composite laminate (105) includes the steps of defining a path (115) across the laminate, the path having a starting location and an ending location and applying a force (109) to and transmitting ultrasonic vibration (111) into the laminate along the path, beginning at the starting location and ending at the ending location. The method further includes determining a temperature of a surface (103, 123) of the laminate proximate to the path and varying at least one of an amplitude of the ultrasonic vibration, the applied force, a feed rate at which the force and the ultrasonic vibration are applied along the path, an angle at which the ultrasonic vibration is applied to the laminate, and an interval at which plies of the laminate are processed, based upon the determined temperature of the surface of the laminate.
    Type: Grant
    Filed: October 11, 2005
    Date of Patent: February 22, 2011
    Assignee: Textron Innovations Inc.
    Inventors: Edward W. Lee, Avraham Benatar, David Grewell
  • Publication number: 20100176184
    Abstract: A method of ultrasonic welding aluminum parts together includes placing the aluminum parts in an ultrasonic welding apparatus and contacting at least one of the aluminum parts with a horn tip of a weld horn of the ultrasonic welding apparatus. A weld amplitude is profiled during a weld cycle of the ultrasonic welding apparatus by producing a high weld amplitude above 55 ?m at the horn tip of the weld horn during an initial period of a weld cycle and producing a low weld amplitude below 55 ?m at the horn tip after the initial period.
    Type: Application
    Filed: March 24, 2010
    Publication date: July 15, 2010
    Applicant: Branson Ultrasonics Corporation
    Inventors: James F. Sheehan, David A. Grewell
  • Publication number: 20080314498
    Abstract: A method for ultrasonic debulking a composite laminate (105) includes the steps of defining a path (115) across the laminate, the path having a starting location and an ending location and applying a force (109) to and transmitting ultrasonic vibration (111) into the laminate along the path, beginning at the starting location and ending at the ending location. The method further includes determining a temperature of a surface (103, 123) of the laminate proximate to the path and varying at least one of an amplitude of the ultrasonic vibration, the applied force, a feed rate at which the force and the ultrasonic vibration are applied along the path, an angle at which the ultrasonic vibration is applied to the laminate, and an interval at which plies of the laminate are processed, based upon the determined temperature of the surface of the laminate.
    Type: Application
    Filed: October 11, 2005
    Publication date: December 25, 2008
    Inventors: Edward W. Lee, Avraham Benatar, David Grewell
  • Publication number: 20080054051
    Abstract: An ultrasonic welding apparatus has a power supply coupled to a weld stack. The weld stack has an ultrasonic transducer coupled to a horn by a booster. The horn has a horn tip. The weld cycle of the ultrasonic welding apparatus is amplitude profiled so that during an initial period, the weld amplitude at the horn tip is high and after the initial period, the weld amplitude is low.
    Type: Application
    Filed: August 13, 2007
    Publication date: March 6, 2008
    Applicant: Branson Ultrasonics Corporation
    Inventors: James Sheehan, David Grewell
  • Patent number: 6867388
    Abstract: A laser imaging apparatus having a laser source outputting a laser beam and an electronic display device. The electronic display device is positioned downstream from the laser source. The electronic display device is operable to selectively polarize a discrete portion of the laser beam to define a modified portion and an unmodified portion. A polarizing filter is then positioned downstream from the display device so as to prevent passage of either the modified portion or the unmodified portion of the laser beam therethrough so as to define an imaging beam having a specific pattern.
    Type: Grant
    Filed: April 8, 2003
    Date of Patent: March 15, 2005
    Assignee: Branson Ultrasonics Corporation
    Inventors: David A. Grewell, Donald C Lovett
  • Publication number: 20040200812
    Abstract: A laser imaging apparatus having a laser source outputting a laser beam and an electronic display device. The electronic display device is positioned downstream from the laser source. The electronic display device is operable to selectively polarize a discrete portion of the laser beam to define a modified portion and an unmodified portion. A polarizing filter is then positioned downstream from the display device so as to prevent passage of either the modified portion or the unmodified portion of the laser beam therethrough so as to define an imaging beam having a specific pattern.
    Type: Application
    Filed: April 8, 2003
    Publication date: October 14, 2004
    Inventors: David A. Grewell, Donald C. Lovett
  • Patent number: 6528755
    Abstract: The present invention is directed to a method and apparatus using a light guide for directing a laser beam to a weld zone. The light guide includes an entrance end, an exit end and a flexible body therebetween. The entrance end of the light guide is operatively coupled to a laser source such as a diode and is adapted to receive and communicate the laser radiation through the light guide. The light guide is formed of a flexible material to permit the exit end of the light guide to be spaced from and aligned with complex two-dimensional and three-dimensional weld zone configurations. The internal reflection of the light guide contains the laser radiation therein as it passes from the entrance end and through the exit end of the light guide. The light guide and corresponding methods of welding parts permit laser welding of complex geometric configurations.
    Type: Grant
    Filed: April 10, 2001
    Date of Patent: March 4, 2003
    Assignee: Branson Ultrasonics Corporation
    Inventors: David A. Grewell, Justin R. Bickford, Donald C. Lovett, Paul A. Rooney
  • Patent number: 6486433
    Abstract: An inflatable bladder system for applying generally uniform pressure to parts being welded to insure proper contact at the welding interface includes a first sheet that is generally transparent to electromagnetic radiation to allow such radiation to pass therethrough. This electromagnetic radiation serves to heat the parts to a temperature sufficient to create a weld. The inflatable bladder also includes a second sheet that is also generally transparent to electromagnetic radiation. The second sheet is coupled to the first sheet to create a sealed volume therebetween. Fluid is selectively introduced into the sealed volume in order to expand the bladder into engagement with the parts being welded to exert a generally uniform pressure thereon.
    Type: Grant
    Filed: January 11, 2001
    Date of Patent: November 26, 2002
    Assignee: Branson Ultrasonics Corporation
    Inventors: David Grewell, Donald C. Lovett
  • Publication number: 20020088777
    Abstract: An inflatable bladder system for applying generally uniform pressure to parts being welded to insure proper contact at the welding interface includes a first sheet that is generally transparent to electromagnetic radiation to allow such radiation to pass therethrough. This electromagnetic radiation serves to heat the parts to a temperature sufficient to create a weld. The inflatable bladder also includes a second sheet that is also generally transparent to electromagnetic radiation. The second sheet is coupled to the first sheet to create a sealed volume therebetween. Fluid is selectively introduced into the sealed volume in order to expand the bladder into engagement with the parts being welded to exert a generally uniform pressure thereon.
    Type: Application
    Filed: January 11, 2001
    Publication date: July 11, 2002
    Inventors: David Grewell, Donald C. Lovett
  • Publication number: 20020008089
    Abstract: The present invention is directed to a method and apparatus using a light guide for directing a laser beam to a weld zone. The light guide includes an entrance end, an exit end and a flexible body therebetween. The entrance end of the light guide is operatively coupled to a laser source such as a diode and is adapted to receive and communicate the laser radiation through the light guide. The light guide is formed of a flexible material to permit the exit end of the light guide to be spaced from and aligned with complex two-dimensional and three-dimensional weld zone configurations. The internal reflection of the light guide contains the laser radiation therein as it passes from the entrance end and through the exit end of the light guide. The light guide and corresponding methods of welding parts permit laser welding of complex geometric configurations.
    Type: Application
    Filed: April 10, 2001
    Publication date: January 24, 2002
    Inventors: David A. Grewell, Justin R. Bickford, Donald C. Lovett, Paul A. Rooney