Patents by Inventor Hannu Virtanen

Hannu Virtanen 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: 6843886
    Abstract: A method and device for processing sewage which contains coating paste from a paper or board mill with a device operating on the principle of a double action impact mill. The device includes a first rotor (11) equipped with blades; a second rotor (12) concentric with the first rotor, equipped with blades and arranged to rotate in a direction opposite to the direction of the first rotor, or a stator concentric with the first rotor and equipped with blades. The sewage is led to a feed opening (14) which opens out to the nave of rotors (11, 12) or to the nave of the rotor and the stator. In the device, the material flow is brought to flow as a flow-off through the blades of the rotors (11, 12) arranged within each other, or of the rotor and the stator arranged within each other.
    Type: Grant
    Filed: November 24, 2000
    Date of Patent: January 18, 2005
    Assignee: Megatrex Oy
    Inventors: Mauno Huovinen, Hannu Virtanen
  • Publication number: 20040188480
    Abstract: A method of separating colouring agents, particularly printing ink, from recycled fibre material, in which method the recycled fibre material is defibered using a liquid, so that colouring agent is separated from the recycled fibre during the defibration. In the method, the pre-kneaded recycled fibre is applied to a double-action impact mill, where it is subjected to successive impacts, so that the treatment time is at most some seconds.
    Type: Application
    Filed: April 9, 2004
    Publication date: September 30, 2004
    Inventors: Carl-Olof Palm, Hannu Virtanen, Esa Pirttinen
  • Patent number: 6229724
    Abstract: A display monitor power supply circuit has a primary side with a power factor correction circuit, a secondary side with a microcontroller for controlling a display monitor, and an isolation interface arranged between the primary side and the secondary side. The microcontroller provides a power correction circuit control signal to the power factor correction circuit for controlling a power correction factor of the display monitor power supply circuit. In operation, the power correction circuit control signal automatically switches the power factor correction circuit to an off state during a power save state. The isolation interface may also provide a supply voltage directly to the power factor correction circuit. The isolation interface may include an isolator circuit for two-way communication signals between the primary side and the microcontroller to fully control the power factor correction circuit.
    Type: Grant
    Filed: December 14, 1999
    Date of Patent: May 8, 2001
    Assignee: Nokia Corporation
    Inventor: Hannu Virtanen
  • Patent number: 6202946
    Abstract: A method and device for defibrating fiber-containing material in a device operating with the pin mill principle. The device includes a housing and in it a first rotor equipped with collision surfaces; a second rotor concentric with the first rotor and equipped with collision surfaces, the second rotor being arranged to rotate in a direction opposite to the first rotor; or a stator concentric with the first rotor and equipped with collision surfaces. Further, the device includes a feed orifice in the housing and opening to the center of the rotors or the rotor and stator, and a discharge orifice on the housing wall and opening to the periphery of the outermost rotor or stator. The fiber-containing material is led from the feed orifice to the housing and made to flow together with air or liquid generating a suspension through the collision surfaces of the nested rotors, or the nested rotor and stator to the discharge orifice and further as a discharge flow out of the housing.
    Type: Grant
    Filed: June 24, 1999
    Date of Patent: March 20, 2001
    Assignee: Megatrex Oy
    Inventor: Hannu Virtanen