Patents by Inventor M. Duncan MacAllister

M. Duncan MacAllister 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).

  • Apparatus and method for conveying amplified sound to ear
    Patent number: 5201007
    Abstract: An earmold and a method of manufacturing an earmold for a hearing aid that conveys amplified sound from the hearing aid into the ear canal to a closed cavity adjacent the tympanic membrane. The earmold includes an acoustic conduction tube having an external diameter smaller than the ear canal and a flexible flanged tip that exerts negligible pressure on the wall of the canal. One end of the tube is held in place in the canal by the flanged tip. The opposite end of the tube may be positioned in the ear aperture by a fitting in the ear concha that may be integral with the tube. The hearing aid and the earmold leave the canal open preferably to a point past the canal isthmus.
    Type: Grant
    Filed: March 5, 1991
    Date of Patent: April 6, 1993
    Assignee: Epic Corporation
    Inventors: Gary L. Ward, M. Duncan MacAllister
  • Apparatus and method for conveying amplified sound to the ear
    Patent number: 5031219
    Abstract: An earmold and a method of manufacturing an earmold for a hearing aid that conveys amplified sound from the hearing aid into the ear canal to a closed cavity adjacent the tympanic membrane. The earmold includes an acoustic conduction tube having an external diameter smaller than the ear canal and a flexible flanged tip that exerts negligible pressure on the wall of the canal. One end of the tube is held in place in the canal by the flanged tip. The opposite end of the tube may be positioned in the ear aperture by a fitting in the ear concha that may be integral with the tube. The hearing aid and the earmold leave the canal open preferably to a point past the canal isthmus.
    Type: Grant
    Filed: September 15, 1988
    Date of Patent: July 9, 1991
    Assignee: Epic Corporation
    Inventors: Gary L. Ward, M. Duncan MacAllister