Patents Represented by Attorney, Agent or Law Firm Washburn Washburn LLP
  • Patent number: 6466031
    Abstract: A fault is located in a transmission line with a sending end, a receiving end, and a plurality of tapped nodes, and multiple tapped loads connected to the transmission line at tap nodes. The sending end and the receiving end each include a measuring device. The fault location is determined by obtaining measured circuit parameters including measured pre-fault and faulted current and voltage values at the sending end and at the receiving end of the transmission line. An equivalent tap node location is calculated using measured pre-fault and faulted current and voltage values at the sending end and at the receiving end of the transmission line. The equivalent tap node divides the transmission line into a sending side and a receiving side. The phase angle difference due to unsynchronized measurement using the measured pre-fault current and the measured pre-fault voltage values may be calculated. The equivalent load impedance of the tapped loads is calculated.
    Type: Grant
    Filed: December 29, 2000
    Date of Patent: October 15, 2002
    Assignee: ABB Power Automation Ltd.
    Inventors: Yi Hu, David Lubkeman, Reto Buettner, David Hart
  • Patent number: 6439709
    Abstract: Methods for reducing cavitation in impulse or drop on demand ink jetting devices are provided. Impulse ink jet compositions comprising antioxidant are also provided which are suitable for printing clear, well-defined alphanumeric text or low spread, narrow bar width bar codes on porous substrates such as Kraft paper or corrugated cardboard. The ink compositions preferably comprise from about 20 to 50 percent by weight of a carbon black dispersion, from about 10 to 20 percent by weight of a dispersion medium, from about 40 to 60 percent by weight of a plasticizer and less than 2% of an antioxidant additive. The antioxidant additive lowers the dissolve oxygen level in the ink, thereby enhancing the jetting perfomance of the printhead.
    Type: Grant
    Filed: June 9, 1999
    Date of Patent: August 27, 2002
    Assignee: Trident International, Inc.
    Inventors: Deverakonda S. Sarma, James E. Fox, Alan L. Hudd, Thyagaraja Sarada, Brian Salisbury