William G. Krawczak

Person

  • White Bear Lake, MN, US

Patents Grantslast 30 patents

  • Information Patent Grant

    Piston loudspeaker

    • Patent number 4,013,846
    • Issue date Mar 22, 1977
    • Minnesota Mining and Manufacturing Company
    • William G. Krawczak
    • H04 - ELECTRIC COMMUNICATION TECHNIQUE