Patents by Inventor Lennart A. Stenstrom

Lennart A. Stenstrom 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: 10908186
    Abstract: A monitoring arrangement for monitoring a surge arrester which is connected to a live wire of a power network at a connection point in order to protect an electrical apparatus against incoming surges, the monitoring arrangement including: an analogue measuring circuit for sensing a current impulse through the surge arrester caused by an incoming surge in the live wire and producing a corresponding analogue measuring signal; an analog-to-digital converter for converting the measuring signal into digital signals; and an electronic processing device configured: to establish, based on the digital signals, a voltage peak value representing the highest voltage at the connection point during the incoming surge; and to establish, based on the voltage peak value and by means of a calculation model or look-up table, a maximum-voltage value representing an estimated maximum voltage across the electrical apparatus during the incoming surge.
    Type: Grant
    Filed: December 9, 2016
    Date of Patent: February 2, 2021
    Assignee: ABB POWER GRIDS SWITZERLAND AG
    Inventors: Håkan Westerlund, Lennart Stenström
  • Publication number: 20200271695
    Abstract: A monitoring arrangement for monitoring a surge arrester which is connected to a live wire of a power network at a connection point in order to protect an electrical apparatus against incoming surges, the monitoring arrangement including: an analogue measuring circuit for sensing a current impulse through the surge arrester caused by an incoming surge in the live wire and producing a corresponding analogue measuring signal; an analog-to-digital converter for converting the measuring signal into digital signals; and an electronic processing device configured: to establish, based on the digital signals, a voltage peak value representing the highest voltage at the connection point during the incoming surge; and to establish, based on the voltage peak value and by means of a calculation model or look-up table, a maximum-voltage value representing an estimated maximum voltage across the electrical apparatus during the incoming surge.
    Type: Application
    Filed: December 9, 2016
    Publication date: August 27, 2020
    Inventors: Håkan Westerlund, Lennart Stenström
  • Patent number: 8717732
    Abstract: A high voltage surge arrester, including a varistor element arranged so as to be connected to a high voltage source and to carry a high voltage when being positioned in its operative position, and an electric insulator that encloses and is in contact with the varistor element and forms an outer surface of the apparatus, wherein the electric insulator includes a silicone-based rubber. The silicone based rubber includes particles chosen from the group consisting of Al2O3, BN and ZnO, to such an extent that the thermal conductivity of the silicone-based rubber is equal to or above 0.8 W/mK.
    Type: Grant
    Filed: June 4, 2012
    Date of Patent: May 6, 2014
    Assignee: ABB Research Ltd.
    Inventors: Lennart Stenström, Linnea Petersson, Xavier Kornmann, Henrik Hillborg
  • Publication number: 20120250207
    Abstract: A high voltage surge arrester, including a varistor element arranged so as to be connected to a high voltage source and to carry a high voltage when being positioned in its operative position, and an electric insulator that encloses and is in contact with the varistor element and forms an outer surface of the apparatus, wherein the electric insulator includes a silicone-based rubber. The silicone based rubber includes particles chosen from the group consisting of Al2O3, BN and ZnO, to such an extent that the thermal conductivity of the silicone-based rubber is equal to or above 0.8 W/mK.
    Type: Application
    Filed: June 4, 2012
    Publication date: October 4, 2012
    Inventors: Lennart Stenström, Linnea Petersson, Xavier Kornmann, Henrik Hillborg
  • Patent number: 8154839
    Abstract: An arrester includes at least one elongate outer first housing made of an electrically insulating material, a pair of electrical terminals at opposite ends of the first housing, an array of electrical components arranged in the first housing that form a series path between the terminals, and a voltage grading arrangement for providing a substantially uniform voltage gradient along the arrester, wherein the voltage grading arrangement includes (i) an elongated outer second housing, and (ii) capacitor circuitry arranged in the outer second housing, and wherein the outer second housing is arranged external to the outer first housing.
    Type: Grant
    Filed: July 1, 2010
    Date of Patent: April 10, 2012
    Assignee: ABB Technology AG
    Inventors: Lennart Stenström, Pär Barkensjö
  • Publication number: 20100265623
    Abstract: An arrester includes at least one elongate outer first housing made of an electrically insulating material, a pair of electrical terminals at opposite ends of the first housing, an array of electrical components arranged in the first housing that form a series path between the terminals, and a voltage grading arrangement for providing a substantially uniform voltage gradient along the arrester, wherein the voltage grading arrangement includes (i) an elongated outer second housing, and (ii) capacitor circuitry arranged in the outer second housing, and wherein the outer second housing is arranged external to the outer first housing.
    Type: Application
    Filed: July 1, 2010
    Publication date: October 21, 2010
    Inventors: Lennart Stenström, Pär Barkensjö
  • Patent number: 5661945
    Abstract: A universal beam for supporting a movable load is capable of handling heavier loads than prior systems and can be constructed of aluminum extrusions or other materials allowing high accuracy, and has good torsional stiffness and other desired properties. A symmetrical U-shaped profile extrusion has parallel shanks extending downwardly from a top and a connecting member between the shanks. Between the connecting member and the bottom of the extrusion a load supporting, guiding and driving volume is provided. The shanks between the connecting member and the top, except at the corners, have a thickness that is at most 4% of the extrusion width. The connecting member includes a central wall, first and second drums adjacent locally reinforced portions of the shanks, a generally flat bottom portion, and inner walls substantially parallel to the shanks and having a substantially flat inner surface.
    Type: Grant
    Filed: January 25, 1996
    Date of Patent: September 2, 1997
    Assignee: Transman AB
    Inventors: Anders Henriksson, Lennart Stenstrom, Valter Stenstrom
  • Patent number: 5570264
    Abstract: A surge arrester with an elongated polymer housing (1) includes a stack of arrester elements (2), for example of zinc oxide. To limit the radial voltage stress which may arise in the polymer material upon pollution, the polymer housing (1) is provided on the outside with field-equalizing control electrodes (6) in the form of bands or rings of metal at regular distances along the arrester. The control electrodes (6) are electrically connected to the ZnO stack (2, 3) inside the housing (1).
    Type: Grant
    Filed: September 11, 1995
    Date of Patent: October 29, 1996
    Assignee: Asea Brown Boveri AB
    Inventors: Jan Lundquist, Lennart Stenstrom
  • Patent number: 5526219
    Abstract: The invention relates to a surge arrester arrangement comprising a surge arrester with a number of ZnO blocks arranged between two end electrodes as well as a cut-out device arranged in series with the arrester for automatically disconnecting the arrester in the event of arrester failure. The central part in the cut-out device is a ZnO block (1) with a higher relative energy capability than the blocks in the arrester. In this way, the block in the cut-out device can only break if the arrester connected in series with the device has failed, whereby incorrect tripping of the device is prevented.
    Type: Grant
    Filed: August 30, 1994
    Date of Patent: June 11, 1996
    Assignee: Asea Brown Boveri AB
    Inventors: Lennart Stenstrom, Bengt Thors
  • Patent number: 5366296
    Abstract: A packaging container having a discharging or docketing device for allowing uninterrupted aseptic connection to for instance a hose having an orifice.The container has a channel (13') of a flexible material terminated by a grip flap (16). The flap (16) is torn away along tearing denotations (17, 17') and weakenings (19, 20) for opening the channel. By locating the weakenings (16) such that they do not coincide, there is obtained at least one protruding portion which will expose a portion on the inside of the channel when the channel is opened up.This portion then acts as an entering surface for facilitating connection.
    Type: Grant
    Filed: June 10, 1993
    Date of Patent: November 22, 1994
    Assignee: AB Tetra Pak
    Inventors: Lennart A. Stenstrom, Lennart S. Wahlstrom, Bert S. Wikholm
  • Patent number: 5317473
    Abstract: The invention relates to a surge arrester assembly with a plurality of parallel-connected arrester units (1) with polymer casing mounted in a rack. The lower and upper parts of the rack consist of bars (4a, 4b) of, for example, aluminium, which are included in the electric circuit. The bars are retained by, for example, support insulators (6) of porcelain or polymer material. The mechanical retention of the stacks of ZnO blocks of the arrester units (1) and the necessary contact pressure between the blocks are ensured by the rack structure. The electrical connections (23, 24) to the rack are arranged in such a way that, if a fault causing a short circuit in one of the block stacks occurs, the arc produced is blown by the current forces along the bars to the opposite end, where arcing horns (38) of a current-resistant material, for example steel, are arranged and where the arc may burn in a controlled manner without involving a risk to the environment. (FIG.
    Type: Grant
    Filed: August 31, 1992
    Date of Patent: May 31, 1994
    Assignee: Asea Brown Boveri AB
    Inventors: Jan Lundquist, Lennart Stenstrom, Sven Akervall
  • Patent number: 5251982
    Abstract: A packaging container having a discharging or docketing device for allowing uninterrupted aseptic connection to for instance a hose having an orifice.The container has a channel (13') of a flexible material terminated by a grip flap (16). The flap (16) is torn away along tearing denotations (17, 17') and weakenings (19, 20) for opening the channel. By locating the weakenings (16) such that they do not coincide there is obtained at least one protruding portion which will expose portion on the inside of the channel when the channel is opened up.This portion then acts as an entering surface for facilitating connection.
    Type: Grant
    Filed: October 27, 1992
    Date of Patent: October 12, 1993
    Assignee: AB Tetra Pak
    Inventors: Lennart A. Stenstrom, Lennart S. Wahlstrom, Bert S. Wikholm
  • Patent number: 5165801
    Abstract: A package is disclosed comprising two members formed together. One of the members is a closed member of cardboard or a corresponding material, and the other member is flexible. The rigidifying member has a closed peripheral portion, and a completely covering bottom which is continuous with the peripheral portion. The flexible member is fastened along its entire periphery at sufficient points on the outer member such that the package has a stable shape.
    Type: Grant
    Filed: October 28, 1991
    Date of Patent: November 24, 1992
    Assignee: AB Akerlund & Rausing
    Inventors: Lennart A. Stenstrom, Lennart Wahlstrom
  • Patent number: 5131542
    Abstract: A display package for a plurality of teat cup liners has a support structure (1) of a foldable sheet material comprising a plane wall portion (2), and a support flap (3), which hangs together with the wall portion (2) and is folded substantially transverse to the latter, the support flap (3) being provided with a plurality of recesses (12) situated aligned with each other. Each recess (12) has an extension, which is larger than the diameter of the tubular portion (2)5 of the teat cup liner, but less than the diameter of the head portion (26) of the teat cup liner. The tubular portions (25) of the teat cup liners extend through the recesses (12) and along the wall portion (2) substantially parallel with each other, so that the teat cup liners are supported by the support flap (3) and the wall portion (2), the head portions (26) abutting against the support flap (3).
    Type: Grant
    Filed: March 27, 1991
    Date of Patent: July 21, 1992
    Assignee: Alfa-Laval Agriculture Intl AB
    Inventor: Lennart Stenstrom
  • Patent number: 5096306
    Abstract: A package is disclosed comprising two members formed together. One of the members is a closed member of cardboard or a corresponding material, and the other member is flexible. The rigidifying member has a closed peripheral portion, and a completely covering bottom which is continuous with the peripheral portion. The flexible member is fastened along its entire periphery at sufficient points on the outer member such that the package has a stable shape.
    Type: Grant
    Filed: September 5, 1989
    Date of Patent: March 17, 1992
    Assignee: Tetra Pak AB
    Inventors: Bengt Perrson, Lennart A. Stenstrom, Lennart Wahlstrom
  • Patent number: 4860156
    Abstract: A trigger circuit for a spark gap chain with at least two series-connected spark gaps, of which at least one is provided with at least one trigger electrode, includes a resistor chain which is connected in parallel with the spark gap chain and comprises at least two series-connected resistor groups. That of the resistor groups which is connected in parallel with the spark gap provided with a trigger electrode comprises a voltage-dependent resistor, built up of zinc oxide varistors, which is connected in series with a linear resistor. The voltage across the linear resistor is supplied to the trigger electrode of the spark gap for ignition of the spark gap when this voltage amounts to a pre-determined value. The spark gaps are primarily intended to be utilized for overvoltage protection of series capacitors.
    Type: Grant
    Filed: September 2, 1988
    Date of Patent: August 22, 1989
    Assignee: Asea Brown Boveri AB
    Inventors: Lennart Stenstrom, Allan Akerstedt
  • Patent number: D301822
    Type: Grant
    Filed: August 19, 1985
    Date of Patent: June 27, 1989
    Inventors: Lennart Stenstrom, Lennart Wahlstrom
  • Patent number: D301823
    Type: Grant
    Filed: August 19, 1985
    Date of Patent: June 27, 1989
    Inventors: Lennart Stenstrom, Lennart Wahlstrom
  • Patent number: D301960
    Type: Grant
    Filed: August 19, 1985
    Date of Patent: July 4, 1989
    Inventor: Lennart Stenstrom
  • Patent number: D328026
    Type: Grant
    Filed: March 29, 1989
    Date of Patent: July 21, 1992
    Assignee: Alfa-Laval Agriculture International AB
    Inventor: Lennart Stenstrom