Patents Assigned to Maxi-Switch Company
  • Patent number: 4132487
    Abstract: This invention relates to a keyboard switch or push button transducer for use in keyboards which makes use of the advantages of resistive and capacitive methods of closure. The switch element is comprised of a resilient conductive element attached to a pad of compressible foam mounted on the end of a key plunger. When the push button or switch plunger is depressed, the switch element is brought into contact with conductive elements etched on a printed circuit board. One of the conductive elements has a coating of dielectric material thereon, and the other conductive element has a raised conductive surface to contact the conductive elastomer sheet prior to the contact with the dielectric material. The insulated area forms a capacitance between the elastomer sheet and the conductive element or metallic pad on the printed circuit board, and the other area of conductor element, being uninsulated, makes a resistive contact with the elastomer.
    Type: Grant
    Filed: May 16, 1977
    Date of Patent: January 2, 1979
    Assignee: Maxi-Switch Company
    Inventor: Robert P. Fisher