Via Helical Arrangement Of Projections Patents (Class 400/156)
  • Patent number: 6485205
    Abstract: This invention relates to a media weight sensor of the type that includes a transducer consisting of a metal desk with a piezoelectric element fabricated by one side which form the back of a Helmholtz resonator cavity mounted in a printer so that the media going to the printer moves across the top of the Helmholtz resonator where an opening of the resonator is located. A soft, polymeric roller is used to press for media and is the transducer. The resonant frequency of the Helmholtz is affected by the media. The mass of the media adds to the mass of the resonator, thereby lowering the resonant frequency. Consequently, the heavier than media, the more the resonant frequency is lowered.
    Type: Grant
    Filed: December 19, 2000
    Date of Patent: November 26, 2002
    Assignee: Hewlett-Packard Company
    Inventor: Phillip R. Luque