Patents by Inventor David A. Samdahl

David A. Samdahl 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).

  • Control switch and potentiometer for hearing aids and the like
    Patent number: 4803458
    Abstract: A control switch and potentiometer assembly for use in an in-the-canal type hearing air comprising a miniature single pole, single or double throw, push-pull control switch and rotary potentiometer. The components of the control switch and potentiometer are mounted within a durable thermoplastic resin housing which is anchored within the hearing aid. A single control knob for actuation of the control switch and potentiometer is raised and shaped to permit gripping between the fingertips of the user for removing the hearing aid from the ear canal.The switch contacts and switch wiper are designed such that the process of pulling on the potentiometer control knob to remove the hearing aid will extend the control switch, thereby disengaging a normally closed switch contact and opening a battery powered circuit so as to turn the hearing aid off.
    Type: Grant
    Filed: August 28, 1987
    Date of Patent: February 7, 1989
    Assignee: Wilbrecht Electronics, Inc.
    Inventors: John A. Trine, David A. Samdahl, Daryle L. Petersen