Patents by Inventor Chul-hue Park

Chul-hue Park 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).

  • Multi-mode vibration damping device and method using negative capacitance shunt circuits
    Patent number: 6870303
    Abstract: A novel multi-mode vibration damper is invented by using a pair of piezoelectric patches connected with negative capacitance shunt circuit units. A piezoelectric material connected with a series resistor-negative capacitor branch circuit is capable of suppressing the vibration and/or noise amplitudes in the low frequency range. The other piezoelectric material connected with a parallel resistor-negative capacitor circuit is for suppressing the vibration and/or noise amplitudes in the high frequency range. By combining two negative capacitance shunt circuit units, a multi-mode vibration damper is capable of suppressing the whole structure modes simultaneously. In order to describe the characteristic behaviors of a multi-mode vibration damper, the stiffness ratio and loss factor with respect to the non-dimensional frequency are considered. The mechanism of a shunt damper is also described as considering a shunt voltage generated by the shunt impedance.
    Type: Grant
    Filed: May 5, 2003
    Date of Patent: March 22, 2005
    Assignee: Pohang University of Science and Technology Foundation
    Inventor: Chul-hue Park
  • Multi-mode vibration damping device and method using negative capacitance shunt circuits
    Publication number: 20030209953
    Abstract: A novel multi-mode vibration damper is invented by using a pair of piezoelectric patches connected with negative capacitance shunt circuit units. A piezoelectric material connected with a series resistor-negative capacitor branch circuit is capable of suppressing the vibration and/or noise amplitudes in the low frequency range. The other piezoelectric material connected with a parallel resistor-negative capacitor circuit is for suppressing the vibration and/or noise amplitudes in the high frequency range. By combining two negative capacitance shunt circuit units, a multi-mode vibration damper is capable of suppressing the whole structure modes simultaneously. In order to describe the characteristic behaviors of a multi-mode vibration damper, the stiffness ratio and loss factor with respect to the non-dimensional frequency are considered. The mechanism of a shunt damper is also described as considering a shunt voltage generated by the shunt impedance.
    Type: Application
    Filed: May 5, 2003
    Publication date: November 13, 2003
    Applicant: Pohang University of Science and Technology Foundation
    Inventor: Chul-Hue Park