Patents by Inventor Lars Ehnstrom

Lars Ehnstrom 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: 6500344
    Abstract: Method and arrangement for filtering particles out of a liquid, in which the liquid containing particles is supplied to a sedimentation tank (12), and the liquid is made, by means of hydrostatic liquid pressure prevailing in the tank, to flow through a filter member (18) on the shell surface of a drum (14) mounted in the tank (12). When the liquid in the tank has risen to a predetermined level above the drum (14) as a result of clogging of the filter member (18), cleaning of the filter member (18) in situ in the tank is initiated.
    Type: Grant
    Filed: January 2, 2001
    Date of Patent: December 31, 2002
    Inventors: Hyosong Lee, Lars Ehnstrom
  • Patent number: 6248053
    Abstract: The invention relates to a device and process for centrifugal separation of solid particles from a liquid. The device comprises a vessel rotatable around a vertical axis. The vessel has a separation zone with separation surface elements. The separation surface elements are formed by a plurality of adjacent, axially oriented tubular elements or channels open at both ends. The process is characterized in that the liquid is caused to flow with essentially laminar flow through a plurality of axially oriented, parallel channels and is subjected to a g-number, preferably less than 100, in order to centrifugally deposit the particles on the channel walls.
    Type: Grant
    Filed: March 2, 2000
    Date of Patent: June 19, 2001
    Inventors: Lars Ehnström, Hyosong Lee
  • Patent number: 6083147
    Abstract: A device and a process for centrifugal separation of solid particles from a liquid is disclosed. The device comprises a vessel rotatable around a vertical axis. The vessel has a separation zone with separation surface elements. The separation surface elements are formed by a plurality of adjacent, axially oriented tubular elements or channels open at both ends. The process is characterized in that the liquid is caused to flow with essentially laminar flow through a plurality of axially oriented, parallel channels and is subjected to a g-number, preferably less than 100, in order to centrifugally deposit the particles on the channel walls.
    Type: Grant
    Filed: March 11, 1998
    Date of Patent: July 4, 2000
    Assignee: Centritech HB
    Inventors: Lars Ehnstrom, Hyosong Lee
  • Patent number: 5700378
    Abstract: The invention relates to a method and an apparatus for the gravitational separation of fine particles out of a liquid. The liquid containing the particles which are to be separated is conducted with laminar flow through the gaps between a plurality of closely separated, essentially horizontally orientated surface-forming elements (16). The liquid flow through the gaps is interrupted when the particle concentration in the liquid which has flowed through the gaps exceeds a predetermined value. The surface-forming elements (16) are repositioned to an essentially vertical discharging position in order to remove the particle collection present on the surface-forming elements. The surface-forming elements (16) are then returned to the essentially horizontal working position and a new gravitational separation cycle begins.
    Type: Grant
    Filed: March 19, 1996
    Date of Patent: December 23, 1997
    Assignee: Vivex AB
    Inventors: Hyosong Lee, Lars Ehnstrom
  • Patent number: 4950401
    Abstract: The invention concerns a centrifugal separator with a rotor (15), in which a flexible member (28), e.g. a hose, extends a distance along the periphery of the rotor. The hose defines two parallel channels (29, 30), which form a separation chamber in the rotor and extend from the peripheral part of the rotor towards the rotor center; from there axially out of the rotor (15) at one axially directed side thereof, around the rotor to its opposite side and to a point (27) aligned with the rotor axis (C). During the operation of the rotor the hose may be rotated intermittently around its longitudinal axis relative to the rotor body, so that the radially inner and outer walls of the separation chamber are changing places.
    Type: Grant
    Filed: February 2, 1989
    Date of Patent: August 21, 1990
    Assignee: Alfa-Laval Separation AB
    Inventors: Peter Unger, Eric Westberg, Lars Ehnstrom
  • Patent number: 4778444
    Abstract: In a centrifugal separator a flexible member for the transport of liquid to or from a centrifuge rotor is arranged to rotate around a rotating rotor in the same direction as the rotor but with only half of its rotational speed. By such rotation the flexible member may be firmly connected with both the rotor and a stationary member without being twisted. According to the invention the flexible member has a high torsional stiffness, good tensile strength and an outside having good wear resistance. The casing comprises interplaited threads which may be metal or plastic, some of which extend helically with a certain pitch around the flexible member and others of which extend helically with an opposite pitch around the member. The interplaiting of the threads is such that the casing per se is axially compressible and expandable under radial expansion and compression, respectively. As mounted, the casing is axially expanded so that through radial compression it is in frictional engagement with the flexible member.
    Type: Grant
    Filed: September 2, 1987
    Date of Patent: October 18, 1988
    Assignee: Alfa-Laval Separation AB
    Inventors: Eric Westberg, Lars Ehnstrom
  • Patent number: 4662866
    Abstract: In a centrifugal separator, an outlet member (9) is rotatable in the centrifuge rotor (1, 2) in a way such that it may be entrained in rotation by liquid supplied to the rotor. The outlet member (9) has an outlet channel (11) leading from one place within the rotor, where a separated mixture component is present, to a reception place (13) for the mixture component. A first means (19) is arranged to counteract rotation of the outlet member (9) so that a desired relative movement is obtained between the outlet member (9) and the separated mixture component in the rotor which is to be removed. A second means (27-30) senses the magnitude of the force by which the outlet member (9) is counteracting the braking effect of said first means. The first means (19) is connected with the second means (27-30) and arranged to accomplish a desired relative movement between the outlet member (9) and the separated component in the rotor in response to the magnitude of said sensed force.
    Type: Grant
    Filed: December 4, 1985
    Date of Patent: May 5, 1987
    Assignee: Alfa-Laval AB
    Inventor: Lars Ehnstrom
  • Patent number: 4662867
    Abstract: In a centrifugal separator an outlet member (9) is rotatably arranged within the centrifuge rotor (1, 2) such that it can be entrained in rotation by liquid having been supplied to the rotor. The outlet member (9) forms a groove (13) which is open towards the rotor axis and in which there opens an outlet channel (11) starting in the part of the rotor which contains, during operation of the rotor, a separated liquid component. A non-rotatable outlet member (7) has at least one outlet passage (8), one end of which opens in said groove (13) at a level where separated liquid component will be present during operation of the rotor only when the rotatable outlet member (9) is caused to rotate with a certain lower speed than the liquid within the rotor.
    Type: Grant
    Filed: December 4, 1985
    Date of Patent: May 5, 1987
    Assignee: Alfa-Laval AB
    Inventor: Lars Ehnstrom
  • Patent number: 4634416
    Abstract: At a centrifugal separator the centrifuge rotor has an inlet (24) to a separating chamber (4) for a fluid mixture of components to be separated, and means for removing of one separated component from another during the operation of the rotor. Said means comprise an outlet member (15) which is arranged to be entrained in rotation by fluid having been supplied to the rotor but which--at least intermittently--may be caused to rotate at a lower speed than said fluid. A channel (16) extends through the outlet member (15) from a point in the rotor, where the separated component is situated, to a reception place therefor. The reception place may be arranged either within or outside the rotor.
    Type: Grant
    Filed: December 12, 1984
    Date of Patent: January 6, 1987
    Assignee: Alfa-Laval AB
    Inventor: Lars Ehnstrom
  • Patent number: 4552775
    Abstract: A high quality animal feed stuff is produced by thermal dewatering of liquid stillage obtained from fermentation of grain raw material and distillation of the fermentation product. The liquid stillage is mixed with particles of already dewatered product and the mixture is granulated in a granulation device to form essentially spherical granules with a dry substance content of 50-70% by weight, the major part of the granules having a particle diameter in the range of 2-6 mm, whereafter the granules are dried by being conveyed as a porous bed in a controlled path in contact with hot gas of a temperature less than 100.degree. C., and whereafter a part of the dried granules with a desired particle size are discharged and the remaining part of the granules after possible disintegration are recirculated to the granulation step.
    Type: Grant
    Filed: February 28, 1983
    Date of Patent: November 12, 1985
    Assignees: Alfa-Laval AB, Svenska Lantmannens Riksforbund, Forening u.p.a
    Inventors: Peter Baeling, Lars Ehnstrom