Patents by Inventor Wulf Andra

Wulf Andra 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).

  • Patent number: 6011390
    Abstract: An arrangement for a magnetoresistive sensor chip has two Wheatstone brid to determine the sine and cosine of the angle formed between a chip edge and the direction of the magnetic field. All resistances of the bridges consist of a plurality of magnetoresistive laminated elements (2) with current connections made of highly conductive thin films with parallel edges. When the resistances of a bridge are directly electrically interconnected, these edges form angles (5) of 90.degree. each. The parallel edges of the corresponding resistances of the sine and cosine bridges are mutually offset by 45.degree.. The magnetoresistive laminated elements (2) are distributed on the chip surface to reduce angle measurement errors to a minimum. Also disclosed are arrangements that allow the sensor chips to be used for measuring angles and positions.
    Type: Grant
    Filed: December 11, 1997
    Date of Patent: January 4, 2000
    Assignee: Institut fur Mikrostrukturtechnologie und Optoelektronik E.V.
    Inventors: Uwe Loreit, Fritz Dettman, Wulf Andra
  • Patent number: 5796249
    Abstract: A sensor for sensing at least one of angular position and rotation speed comprises a permanent magnet rotatable about an axis of rotation and at least three Wheatstone bridges each having four bridge resistors formed of magnetoresistive strip lines extending in planes parallel to a rotation plane of the permanent magnet. The bridge resistors of each of the at least three Wheatstone bridges are disposed on respective sides of quadrangles corresponding to respective ones of the at least three Wheatstone bridges. Each of the at least three Wheatstone bridges has two adjacently arranged ones of the bridge resistors connected to a half-bridge of respective ones of the at least three Wheatstone bridges. The quadrangles are disposed relative to one another rotated by a preselectable angle .alpha..
    Type: Grant
    Filed: October 30, 1996
    Date of Patent: August 18, 1998
    Assignees: Institut fuer Physikalische Hochtechnologle e.V., HL Planartechnik GmbH
    Inventors: Wulf Andra, Roland Mattheis