Patents by Inventor Bengt R. Johansson

Bengt R. Johansson 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: 4458779
    Abstract: A silencer comprising one or more sound-absorbing parts of ceramic material. The ceramic material is porous and the sound-absorbing parts are self-supporting and have a specific resistance to air flow of 10.sup.3 -10.sup.7 Pas/m.sup.2 and a compression strength of at least 40 kN/m.sup.2, preferably at least 400 kN/m.sup.2.
    Type: Grant
    Filed: June 23, 1982
    Date of Patent: July 10, 1984
    Assignee: Antiphon AB
    Inventors: Bengt R. Johansson, Lennart H. Slycke, Gote V. Norrbrand
  • Patent number: 4253543
    Abstract: Device for absorption of airborne sound, comprising a rigid, air permeable and self-supporting carrying layer having a flexible, air impermeable membrane applied thereto. The device is characterized in that the carrying layer has an air flow resistance of less than 10,000 Pas/m, that the layer has a thickness of 1-60 mm, preferably 5-20 mm, and that at least one surface of the layer is provided with a relief pattern. The device is further characterized in that a flexible membrane having a surface weight of less than 2 kg/m.sup.2 is firmly attached to the carrying layer by gluing or the like. The membrane is resting on the upper parts of the relief pattern, whereby an air gap is obtained between the membrane and the lower parts of the relief pattern.
    Type: Grant
    Filed: January 16, 1979
    Date of Patent: March 3, 1981
    Assignee: Antiphon AB
    Inventor: Bengt R. Johansson