Patents Assigned to National Gypsum Company
  • Patent number: 5718759
    Abstract: A cementitious composition useful for water-resistant construction materials, including floor underlayments, backing boards, self-leveling floor materials, road patching materials, fiberboard, fire-proofing sprays, and fire-stopping materials includes about 20 wt. % to about 75 wt. % calcium sulfate beta-hemihydrate, about 10 wt. % to about 50 wt. % Portland cement, about 4 wt. % to about 20 wt. % silica fume and about 1 wt. % to about 50 wt. % pozzolanic aggregate. The Portland cement component may also be a blend of Portland cement with fly ash and/or ground blast slag.
    Type: Grant
    Filed: October 18, 1996
    Date of Patent: February 17, 1998
    Assignee: National Gypsum Company
    Inventors: Elisha Stav, Edward A. Burkard, Ronald S. Finkelstein
  • Patent number: 5718797
    Abstract: Apparatus and method for producing gypsum board, comprising apparatus for coating a cover sheet with a relatively high density gypsum slurry, apparatus for forming edge borders on the sheet with relatively high density gypsum slurry, and apparatus for forming a core on the coating and between the edge borders, the core comprising a relatively low density gypsum. The apparatus for coating the sheet comprises a relatively soft pressure roll and a relatively hard coating roll, the two rolls being normally pressed together to form a nip between them and a sheet to be coated passing through the nip. The pressure roll is below the sheet and the coating roll, and the axis of the pressure roll is offset from the axis of the coating roll in upstream direction of the movement of the sheet. The pressure roll has a surface area which contacts and moves in the same direction as the sheet, and the coating roll has a surface area which contacts and moves in the opposite direction of the sheet.
    Type: Grant
    Filed: January 31, 1996
    Date of Patent: February 17, 1998
    Assignee: National Gypsum Company
    Inventors: John L. Phillips, Herman C. Fraley
  • Patent number: 5685903
    Abstract: A cementitious composition useful for water-resistant construction materials, including floor underlayments, backing boards, self-leveling floor materials, road patching materials, fiberboard, fire-proofing sprays, and fire-stopping materials includes about 20 wt. % to about 75 wt. % calcium sulfate beta-hemihydrate, about 10 wt. % to about 50 wt. % Portland cement, about 4 wt. % to about 20 wt. % silica fume and about 1 wt. % to about 50 wt. % pozzolanic aggregate. The Portland cement component may also be a blend of Portland cement with fly ash and/or ground blast slag.
    Type: Grant
    Filed: September 13, 1996
    Date of Patent: November 11, 1997
    Assignee: National Gypsum Company
    Inventors: Elisha Stav, Edward A. Burkard, Ronald S. Finkelstein
  • Patent number: 5661881
    Abstract: An elongated metal structural member including an expanded metal web formed by severing a metal strip along a sinuous path forming a plurality of keystone-shaped tabs on each half, moving the two halves directly away from each other until outer corners of the tabs of one half overlap outer corners of the tabs of the other half, and affixing together the outer corners of one half with outer corners of the other half.
    Type: Grant
    Filed: January 30, 1996
    Date of Patent: September 2, 1997
    Assignee: National Gypsum Company
    Inventor: Robert J. Menchetti
  • Patent number: 5653797
    Abstract: A process for the production of a ready-mixed setting-type joint compound includes the use of calcium sulfate hemihydrate, water, and a set-retarding agent. The retarder includes a polymer composition including acrylic acid and acrylamide monomer units, for example a copolymer (or a mixture of copolymers) of acrylic acid and acrylamide or a blend of a homopolymer of acrylic acid and a homopolymer of acrylamide. The joint compound can be combined with an accelerator including a metallic salt. The joint compound of the invention can be formulated either as a lightweight joint compound or as a conventional weight joint compound. The joint compounds provide short setting times, reduced shrinkage, reduced preparation time, and beneficial application properties.
    Type: Grant
    Filed: April 26, 1996
    Date of Patent: August 5, 1997
    Assignee: National Gypsum Company
    Inventor: Jashbhai M. Patel
  • Patent number: 5644883
    Abstract: A hollow shaft wall stud corner clip adjoins ends of horizontal studs at a shaft wall structure corner and is readily adaptable for supporting core boards in a fire rated ceiling or a fire rated duct and for holding core board in place at a top or a bottom of a horizontal stud hollow shaft wall. The clip has a central web for positioning against a stud or track flange and an angled flange with a core board-supporting extremity.
    Type: Grant
    Filed: December 15, 1995
    Date of Patent: July 8, 1997
    Assignee: National Gypsum Company
    Inventor: Robert J. Menchetti
  • Patent number: 5575131
    Abstract: A hollow shaft wall stud corner clip adjoins ends of horizontal studs at a shaft wall structure corner and is readily adaptable for supporting core boards in a fire rated ceiling or a fire rated duct and for holding core board in place at a top or a bottom of a horizontal stud hollow shaft wall. The clip has a central web for positioning against a stud or track flange and an angled flange with a core board-supporting extremity.
    Type: Grant
    Filed: June 6, 1995
    Date of Patent: November 19, 1996
    Assignee: National Gypsum Company
    Inventor: Robert J. Menchetti
  • Patent number: 5573333
    Abstract: A system for delivering a proper proportion of water and starch to form a slurry on a continuous basis responsive to the rate required for the production of gypsum board has a water input controller and a starch input controller to control the rate of water and starch input to a mix/hold tank and a starch slurry output controller to control the output of slurry from the mix/hold tank to the gypsum board production line. A programmable logic controller monitors the output rate and density of the delivered slurry, compares them to a target value and signals the input controllers and/or the output controller to adjust the input and output rates accordingly.
    Type: Grant
    Filed: August 22, 1994
    Date of Patent: November 12, 1996
    Assignee: National Gypsum Company
    Inventor: Donald P. Dahlman
  • Patent number: 5524410
    Abstract: An elongated metal structural member including an expanded metal web formed by severing a metal strip along a sinuous path forming a plurality of keystone-shaped tabs on each half, moving the two halves directly away from each other until outer corners of the tabs of one half overlap outer corners of the tabs of the other half, and affixing together the outer corners of one half with outer corners of the other half.
    Type: Grant
    Filed: January 31, 1994
    Date of Patent: June 11, 1996
    Assignee: National Gypsum Company
    Inventor: Robert J. Menchetti
  • Patent number: 5485706
    Abstract: A laterally stiffened, elongate, roll-formed metal stud, or equivalent structural member having a central web with alternating deformed and undeformed portions.
    Type: Grant
    Filed: July 21, 1994
    Date of Patent: January 23, 1996
    Assignee: National Gypsum Company
    Inventor: Robert J. Menchetti
  • Patent number: 5483777
    Abstract: A generally flat attachment plate for providing a mounting surface on a side of a Z-stud, which surface is perpendicular to the Z-stud flanges. The plate has tongues on one edge engaging an inwardly directed lip on the Z-stud flange, and means on the opposite edge to affix the plate to the angled web of the Z-stud, such as by tabs which fit into slots on the web. The Z-stud has two rows of slots for use in mounting the plates or for suspending the Z-stud from a ceiling.
    Type: Grant
    Filed: January 31, 1994
    Date of Patent: January 16, 1996
    Assignee: National Gypsum Company
    Inventors: Robert J. Menchetti, Matthew J. Kessler
  • Patent number: 5475961
    Abstract: A hollow shaft wall with horizontal studs held between corner posts and an intermediate vertical wall support post, which intermediate post has a central reinforcement channel, the reinforcement channel has a bottom and two side walls, the channel is filled with strips of gypsum board, and the two side walls have metal channels affixed thereto providing oppositely opening grooves for receiving and supporting the ends of said horizontal studs.
    Type: Grant
    Filed: June 21, 1993
    Date of Patent: December 19, 1995
    Assignee: National Gypsum Company
    Inventor: Robert J. Menchetti
  • Patent number: 5472500
    Abstract: A veneer plaster having strengths of substantially greater than 3,000 psi, abrasion resistance of penetrations less than 0.04 inch with 1,000 cycles of a five-pound brush using a 3M Granule Embedding Testing Machine, made from about 1,800 pounds of calcium sulfate beta hemihydrate, 200 pounds of fine silica sand, and about 4 pounds of a fine, white powder dispersant typified by a melamine-formaldehyde-sodium bisulfite polymer.
    Type: Grant
    Filed: April 28, 1994
    Date of Patent: December 5, 1995
    Assignee: National Gypsum Company
    Inventor: Edmund J. Janicki
  • Patent number: 5464302
    Abstract: An extendible stud, consisting of two substantially identical C-studs each of which has opposed flanges of substantially different widths and inwardly turned lips at the flange outer edges, and each C-stud having an elongate central area in its web located at substantially the middle of said C-stud cross-section, which two C-studs are interconnected by the narrow flange of each being held within the channel formed by the wider flange and the associated lip and web of the other C-stud, and the elongate central areas of the webs of the two C-studs abutting one another.
    Type: Grant
    Filed: August 23, 1993
    Date of Patent: November 7, 1995
    Assignee: National Gypsum Company
    Inventor: Robert J. Menchetti
  • Patent number: 5431279
    Abstract: A bundling tape has two rows of perforations extending from one end of the tape to the other; the perforations are arranged inward of and substantially parallel to the edges. A first band is formed between one edge and a first row of perforations, and a second band is formed between the other edge and the second row of perforations; between the two rows of perforations is a center band tear strip. The bands have co-planar upper and lower surfaces. A laminated bundling tape embodiment also has an additional zipper tape attached to the lower surface of the center band, and apparatus and methods are described for making this laminated tape. Bundles of material, such as wallboard, are fastened together by adhering the bottom surface of the first band to the uppermost sheet of material, and by adhering the bottom portion of the second band to the lowermost sheet.
    Type: Grant
    Filed: July 11, 1994
    Date of Patent: July 11, 1995
    Assignees: National Gypsum Company, The Robinette Company
    Inventors: Joseph R. Robinette, Raymond G. Syracuse
  • Patent number: 5425212
    Abstract: A foldable floor track or ceiling track having 1/8-inch-wide slots in the flanges and a 1/8-inch-high rib in the web, between the slots, permitting the track to be cleanly folded in half at the factory, for convenient packaging and handling, and then unfolded and fastened to the floor and the ceiling at a job site.
    Type: Grant
    Filed: September 16, 1993
    Date of Patent: June 20, 1995
    Assignee: National Gypsum Company
    Inventor: Robert J. Menchetti
  • Patent number: 5390458
    Abstract: A wallboard package having edge protective tape which connects two wallboards face-to-face, with an adhesive film on the tape inner surface adapted for use in affixing the wallboards to wall studs.
    Type: Grant
    Filed: May 20, 1993
    Date of Patent: February 21, 1995
    Assignee: National Gypsum Company
    Inventor: Robert J. Menchetti
  • Patent number: 5383317
    Abstract: A hollow shaft wall having a cavity of a first width substantially throughout said wall and a cavity of a greater width in a limited section for the reception of a relatively deep utility box, the limited section having board omitted on one side thereof, and a short section of board affixed over the omitted section, creating the cavity of a greater width. The short section of board is affixed to boards or studs of the wall by short elongate clips having a pair of channels opening in opposite directions.
    Type: Grant
    Filed: February 8, 1993
    Date of Patent: January 24, 1995
    Assignee: National Gypsum Company
    Inventor: Robert J. Menchetti
  • Patent number: 5361556
    Abstract: Horizontal panels, each consisting of top and bottom horizontal studs, with gypsum boards affixed therebetween, are stacked vertically, with suitable means for maintaining the wall vertical.
    Type: Grant
    Filed: February 25, 1993
    Date of Patent: November 8, 1994
    Assignee: National Gypsum Company
    Inventor: Robert J. Menchetti
  • Patent number: 5358757
    Abstract: A bundling tape has two rows of perforations extending from one end of the tape to the other; the perforations are arranged inward of and substantially parallel to the edges. A first band is formed between one edge and a first row of perforations, and a second band is formed between the other edge and the second row of perforations; between the two rows of perforations is a center band tear strip. The bands have co-planar upper and lower surfaces. A laminated bundling tape embodiment also has an additional zipper tape attached to the lower surface of the center band, and apparatus and methods are described for making this laminated tape. Bundles of material, such as wallboard, are fastened together by adhering the bottom surface of the first band to the uppermost sheet of material, and by adhering the bottom portion of the second band to the lowermost sheet.
    Type: Grant
    Filed: January 25, 1993
    Date of Patent: October 25, 1994
    Assignees: National Gypsum Company, The Robinette Company
    Inventors: Joseph R. Robinette, Raymond G. Syracuse