Patents by Inventor Per J. Ohlsson

Per J. Ohlsson 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).

  • Method and apparatus for sensing and maintaining oscillations in an oscillating system
    Patent number: 4257010
    Abstract: A method and apparatus for delivering energy to an oscillatory system in a signal transmitter to maintain the system in a state of oscillation. A component of the oscillatory system that affects the oscillation frequency is influenced by the magnitude of a measured condition which is to be transmitted by the signal transmitter. The oscillatory state of the system is sensed through a signal path, and energy is delivered to the system through substantially the same signal path, said energy being delivered in the form of pulses at time intervals longer than a whole period of oscillation of the system to maintain the system in a state of oscillation.
    Type: Grant
    Filed: January 19, 1977
    Date of Patent: March 17, 1981
    Assignee: Rederiaktiebolaget Nordstjernan
    Inventors: Sven A. Bergman, Per J. Ohlsson, Karl-Gustav E. Nordqvist