Patents by Inventor Brian J. Keenan

Brian J. Keenan 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).

  • Membrane keyboards
    Patent number: 4920237
    Abstract: A membrane keyboard has two spaced flexible membranes (1 and 2) carrying contact pad assemblies. Acoustic pads (15) of expanding ink are printed on the top surface of the upper membrane (2) between the contact pads (4) and the key buttons used to operate the contact switches formed by the pairs of opposed contact pads, thus reducing the acoustic noise and improving the contact bounce characteristic.Optionally, printed expanding ink is also used to form the spacer (5) between the membranes (1 and 2).
    Type: Grant
    Filed: February 2, 1989
    Date of Patent: April 24, 1990
    Assignee: International Business Machines Corporation
    Inventors: Richard A. Eardley, Brian J. Keenan, Ian A. Lawson, John McAllister