Patents by Inventor Sten Frodin

Sten Frodin 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: 5918760
    Abstract: The invention relates to a hydraulic fluid reservoir comprising a substantially cylindrical wall (1), an upper wall (2) and a lower wall, and two tubular connection pieces (4, 5) for entering and discharging hydraulic fluid into and out from the interior of the reservoir. The two tubular connection pieces, an inlet connection piece (4) and an outlet connection piece (5) are substantially tangentially connected to the cylindrical wall (1) to preserve the momentum of a fluid fed into the reservoir.
    Type: Grant
    Filed: September 16, 1997
    Date of Patent: July 6, 1999
    Assignee: Vickers Incorporated
    Inventors: Sten Frodin, Thomas Dahl
  • Patent number: 5884480
    Abstract: In the field of fluid power control, there is a need for a control scheme that supplies working fluid under pressure to a load in the event of failure of power supplies to control apparatus associated with the circuit. The disclosure relates to a control circuit 10 in which output pressure from a pump 11 is fed to a control piston 13 therefor via a pressure compensator 17. The pressure compensator 17 is biased to disconnect the supply of fluid at outlet pressure when this pressure is below a threshold value, and permit such supply when the outlet pressure exceeds the threshold value determined by the biassing force on the pressure compensator. A proportional control valve 16 may be employed further to counteract the biassing of the pressure compensator 17, whereby to control the threshold pressure at which the compensator 17 operates to feed fluid at control pressure to the piston 13. The invention is of particular use in control circuits eg. for cooling pumps and cooling fans.
    Type: Grant
    Filed: March 21, 1997
    Date of Patent: March 23, 1999
    Assignee: Trinova Limited
    Inventors: Thomas Dahl, Sten Frodin
  • Patent number: 4050366
    Abstract: The present invention relates to an improved grating structure comprising carrying bars, and a plurality of ribs interlocked in said bars. Each of said ribs has holes strategically placed on their extremities such that a locking rod may be inserted through said holes so as to tie the ribs to the carrying bars. The grating structure may be further stabilized by the utilization of locking plates on the ends of the carrying bars.
    Type: Grant
    Filed: November 26, 1975
    Date of Patent: September 27, 1977
    Inventors: Curt Helmer Wiklund, Gunnar Sten Frodin