Patents by Inventor Jorma Ohtonen

Jorma Ohtonen 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: 6366184
    Abstract: The invention comprises a filter consisting of resonators (330, 320, . . . ) with a conducting housing, particularly to be used in networks operating on microwave frequencies. The couplings between the resonators are realised outside the conducting filter housing with the aid of a printed board (310) over a wall (306) of the housing. For a particular coupling a conductor strip (311) extending from one resonator to another is formed on the printed board, and openings (335, . . . ) are made in the resonator walls at the ends of the strips. In order to strengthen the coupling a coupling element (343) extending into the resonator cavity can be fastened as an extension of the strip. The filter connectors (301, . . . ) are also fastened to the printed board. The open filter housing (305) and the inner conductors (331, 341, . . . ) or the resonators can be made as a homogenous body. The manufacturing costs and the tuning costs of a filter according to the invention are relatively low.
    Type: Grant
    Filed: March 3, 2000
    Date of Patent: April 2, 2002
    Assignee: Filtronic LK Oy
    Inventor: Jorma Ohtonen
  • Patent number: 5304968
    Abstract: The present invention relates specifically to the temperature compensation of a resonator in which a rod or a conductor wound in the form of a cylindrical coil serving as an inner conductor is enclosed within a metal cover and in which the open end of the rod or the coil is spaced a given distance from the cover, thus forming a loading capacitance. A change in the resonant frequency caused by thermal expansion can be compensated for in that at the open end of the inner conductor within the housing there is provided a compensation plate (5), the center part (12) of which is spaced at a distance (a) from the top surface (4) of the housing and preferably in parallel therewith and which has at least at two opposite edge parts (8, 9) been attached to the top surface (4).
    Type: Grant
    Filed: October 28, 1992
    Date of Patent: April 19, 1994
    Assignee: LK-Products OY
    Inventors: Jorma Ohtonen, Kimmo Ervasti