Patents by Inventor Nam Hoon Lee

Nam Hoon Lee 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).

  • Publication number: 20080088966
    Abstract: A servo control method in a seek retry condition includes determining whether the seek retry condition is generated, and terminating a servo control process that is currently performed and decelerating a voice coil motor such that a speed of the voice coil motor is minimized using a back electromotive force when the seek retry condition is generated.
    Type: Application
    Filed: August 22, 2007
    Publication date: April 17, 2008
    Inventors: Nam-hoon LEE, Jae-hyeong Kim
  • Patent number: 7180761
    Abstract: Provided is a constant voltage control apparatus capable of reducing feedback lines. In the constant voltage control apparatus, a first amplifier amplifies an output voltage applied to a pair of output terminals. A second amplifier amplifies a voltage drop between one of the output terminals and a load terminal connected thereto. A third amplifier amplifies output voltages from the first and second amplifiers, respectively. Comparing means receive an output voltage from the third amplifier and a reference voltage, and output an output voltage which makes a sum of the output voltage and the reference voltage of the third amplifier become zero. A triac drive unit amplifies the output voltage from the comparing means to control a triac installed on a power line that is connected with the first output terminal.
    Type: Grant
    Filed: September 24, 2004
    Date of Patent: February 20, 2007
    Inventors: Mike T. Deason, Nam-Hoon Lee
  • Publication number: 20060093245
    Abstract: A fluid dynamic bearing is constructed to support stably a rotating body to which a non-uniform force is applied, and a hard disk drive (HDD) employing the fluid dynamic bearing is provided. The fluid dynamic bearing includes a journal bearing part supporting a rotary shaft in a radial direction of the rotary shaft, a thrust part formed at one end of the rotary shaft, a thrust bearing part facing the thrust part and supporting the rotary shaft in a longitudinal direction of the rotary shaft, and a plurality of grooves formed on a surface of the thrust bearing part and/or the thrust part. The plurality of grooves include a first groove group including a plurality of grooves having the same shape and arrangement, and a second groove group adjacent to the first groove group and including at least one groove asymmetric with respect to the grooves of the first groove group.
    Type: Application
    Filed: October 21, 2005
    Publication date: May 4, 2006
    Inventors: Jae-hyuk Han, Dong-ho Oh, Yong-kyu Byun, Cheol-soon Kim, Jeong-seok Koh, Nam-hoon Lee, Ja-choon Koo
  • Publication number: 20060086711
    Abstract: Provided is an improved electrofusion machine comprising: a power supply circuit having a triac configured to have a proper regulation for dropping a commercial voltage to a voltage adapted for a fitting; and a printer unit integrated with the electrofusion unit, for printing information regarding a work result of the fitting. According to the above construction, since the electrofusion machine does not use a transformer occupying 40% of a total weight of the machine, the mobility and portability are enhanced. Also, since the size of the machine is reduced, it is advantageous to deal with the machine on the spot.
    Type: Application
    Filed: September 24, 2004
    Publication date: April 27, 2006
    Inventors: Mike Deason, Nam-Hoon Lee
  • Publication number: 20060034110
    Abstract: Provided is a constant voltage control apparatus capable of reducing feedback lines. In the constant voltage control apparatus, a first amplifier amplifies an output voltage applied to a pair of output terminals. A second amplifier amplifies a voltage drop between one of the output terminals and a load terminal connected thereto. A third amplifier amplifies output voltages from the first and second amplifiers, respectively. Comparing means receive an output voltage from the third amplifier and a reference voltage, and output an output voltage which makes a sum of the output voltage and the reference voltage of the third amplifier become zero. A triac drive unit amplifies the output voltage from the comparing means to control a triac installed on a power line that is connected with the first output terminal.
    Type: Application
    Filed: September 24, 2004
    Publication date: February 16, 2006
    Inventors: Mike Deason, Nam-Hoon Lee
  • Patent number: 6231419
    Abstract: A pen cap that has a propeller attached to the shirt clip found on many pens. The propeller is designed to rotate about a fixed shaft as an amusing diversion for small children or bored executives. An alternative design has a hinge mounted at the top of the clip that allows the clip and propeller to rotate 90 degrees. This increases the range of amusement for the device.
    Type: Grant
    Filed: January 28, 2000
    Date of Patent: May 15, 2001
    Inventor: Nam Hoon Lee