Patents by Inventor Arnold Christiaan Hoogerwerf

Arnold Christiaan Hoogerwerf 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).

  • Watch hairspring and method for making same
    Patent number: 7077562
    Abstract: The invention relates mainly to a hairspring intended to equip the balance wheel of a mechanical timepiece. It is in the form of a spiraled rod (10) cut from an {001} single-crystal silicon plate. Its structure and its dimensions are calculated so as to minimize the thermal drift of the hairspring/balance-wheel assembly by means of the first and second thermal coefficients of its spring constant.
    Type: Grant
    Filed: October 30, 2003
    Date of Patent: July 18, 2006
    Assignee: CSEM Centre Suisse d'Electronique et de Microtechnique SA
    Inventors: Claude Bourgeois, André Perret, Arnold Christiaan Hoogerwerf