Patents by Inventor Lars B. Lundstrom

Lars B. Lundstrom 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: 5205070
    Abstract: A drive arrangement for maneuvering a generally vertically moveable door, the arrangement comprising at least one bendable door lifting element which is connected to at least one of the two longitudinal side edges of the door. In order to enable the force required to maneuver the door to be held substantially constant, or to vary only significantly over the full opening range of the door, particularly in the case of doors of the kind in which the force required to open or maneuver the door increases with the extent to which the door is opened, the door lifting element has connected thereto an elongated, bendable counterbalance device, and the door lifting element will function to move the counterbalance device between an inactive position, in which it is generally horizontal, and an active position in which at least a part of the weight of the counterbalance device will exert a lifting force on the door through the intermediary of the door lifting element.
    Type: Grant
    Filed: February 11, 1992
    Date of Patent: April 27, 1993
    Assignee: Megadoor AB
    Inventor: Lars B. Lundstrom