Patents by Inventor Walton W. Welna

Walton W. Welna 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: 6747074
    Abstract: Described is a flexible, solid fire sealant produced by high shear mixing in a substantially volatile-free state and capable of being molded or extruded into a variety of shapes and used as firestops for windows, doors, dampers, shutters, and through-penetrations, the sealant containing water-insoluble intumescent mineral granules, a polymeric, halogen-free binder, and a flame retardant, wherein the sealant has a softness value from about 0.01 to about 3.75 mm and exhibits high expansion values and chars upon exposure to heat.
    Type: Grant
    Filed: March 26, 1999
    Date of Patent: June 8, 2004
    Assignee: 3M Innovative Properties Company
    Inventors: Mark R. Buckingham, Walton W. Welna
  • Patent number: 5578671
    Abstract: This invention relates to non-aqueous, indefinitely conformable, halogen free, intumescent putty useful in an opening as a firestop material to deter the spread of fire, smoke, and vapors during a fire.
    Type: Grant
    Filed: December 6, 1995
    Date of Patent: November 26, 1996
    Assignee: Minnesota Mining and Manufacturing Company
    Inventor: Walton W. Welna
  • Patent number: 5476891
    Abstract: A flexible, fire-retardant, intumescent composition comprising:a) an intumescent material;b) an effective amount of a stabilizing agent; andc) an organic binder throughout which the intumescent material and stabilizing agent are dispersed, the elastomeric binder being at least partially crosslinked, wherein the stabilizing agent consists essentially of a compound selected from the group consisting of compounds within general formula I ##STR1## wherein R.sup.1 -R.sup.4 inclusive are independently selected from the group consisting of hydrogen and alkyl groups having from 1 to about 5 carbon atoms, with the provisos that:i) either both of R.sup.1 and R.sup.2, or both R.sup.3 and R.sup.4 are alkyl groups having from 1 to about 5 carbon atoms; andii) the stabilizing agent has a melting point ranging from about 105.degree. C. to about 125.degree. C.
    Type: Grant
    Filed: August 11, 1994
    Date of Patent: December 19, 1995
    Assignee: Minnesota Mining and Manufacturing Company
    Inventor: Walton W. Welna
  • Patent number: 4952615
    Abstract: A fireproof, compressible, intumescent, elastomeric material useful to seal expansion joints, curtain wall gaps and penetrations in floors and walls in order to prevent the passage of flame and smoke. A seal of the material retains strength before and after exposure to fire and provides superior resistance to the impact, erosion, and cooling effects of a hose stream used to combat a fire. The composition of this compressible, fireproof material consists of elastomers, vulcanizing agents, fillers, softening agents, and an intumescent. This fireproof material may be in cellular or noncellular form with various degrees of compressibility and softness. It can be produced in sheets, molded parts, and continuous length strips. It may be vulcanized or nonvulcanized.
    Type: Grant
    Filed: May 13, 1988
    Date of Patent: August 28, 1990
    Assignee: Minnesota Mining and Manufacturing Company
    Inventor: Walton W. Welna
  • Patent number: 4177078
    Abstract: A stabilizing agent and backfill composition for providing a thermally stable environment for buried electrical equipment comprising from about 90 to about 99 percent by weight soil and from about 1 to about 10 percent by weight of the stabilizing agent, which is comprised of a mixture of clay and a dispersing agent therefor, wherein the dispersing agent comprises at least about 0.25 percent by weight of the stabilizing agent.
    Type: Grant
    Filed: April 6, 1978
    Date of Patent: December 4, 1979
    Assignee: Minnesota Mining & Manufacturing Company
    Inventors: Walton W. Welna, Lowell C. Frank