Patents by Inventor Junghwan Chang

Junghwan Chang 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).

  • Built-in type electric driving system of machine tool and operation method therefor
    Patent number: 11465251
    Abstract: Disclosed is a built-in type electric driving system of a machine tool. The system is capable of directly connecting a motor, which drives a spindle in a lathe which processes a workpiece, to an outer surface of the spindle without using a belt to rotate the spindle, and is capable of selectively transferring the power of the motor to a rotation system including a drawbar and a spindle for driving a chuck using a clutch device.
    Type: Grant
    Filed: January 23, 2019
    Date of Patent: October 11, 2022
    Assignees: KHAN WORKHOLDING CO., LTD., DONG-A UNIVERSITY RESEARCH FOUNDATION FOR INDUSTRY-ACADEMY COOPERATION
    Inventors: Junghwan Chang, Yongseon Yun, Bonsaeng Ku
  • BUILT-IN TYPE ELECTRIC DRIVING SYSTEM OF MACHINE TOOL AND OPERATION METHOD THEREFOR
    Publication number: 20210053168
    Abstract: Disclosed is a built-in type electric driving system of a machine tool. The system is capable of directly connecting a motor, which drives a spindle in a lathe which processes a workpiece, to an outer surface of the spindle without using a belt to rotate the spindle, and is capable of selectively transferring the power of the motor to a rotation system including a drawbar and a spindle for driving a chuck using a clutch device.
    Type: Application
    Filed: January 23, 2019
    Publication date: February 25, 2021
    Applicants: KHAN WORKHOLDING CO., LTD., DONG-A UNIVERSITY RESEARCH FOUNDATION FOR INDUSTRY-ACADEMY COOPERATION
    Inventors: Junghwan CHANG, Yongseon YUN, Bonsaeng KU
  • Brushless DC motor with armature windings compensated by auxiliary windings
    Patent number: 6628034
    Abstract: A brushless DC motor with armature windings is compensated by auxiliary windings wound around linking parts of each pair of adjacent teeth of the slotted stator, to increase the number of effective turns, thus improving the torque constant and efficiency of the motor. The motor includes a slotted stator formed with a number of teeth, main windings concentrically wound around the teeth of the stator, auxiliary windings for compensating the main windings wound concentrically around the linking parts of the teeth and connected to the main windings, and a rotor with permanent magnets and a yoke.
    Type: Grant
    Filed: June 12, 2001
    Date of Patent: September 30, 2003
    Assignee: Hanyang Hak Won Co., Ltd.
    Inventors: Gunhee Jang, Junghwan Chang, Kyungsu Kim
  • Brushless DC motor with armature windings compensated by auxiliary windings
    Publication number: 20020185929
    Abstract: The present invention relates to a brushless DC motor with armature windings compensated by auxiliary windings, and particularly to a brushless DC motor with armature windings compensated by auxiliary windings wound around the linking parts of each pair of adjacent teeth of the slotted stator, to increase the number of effective turns, thus improving the torque constant and efficiency of the motor.
    Type: Application
    Filed: June 12, 2001
    Publication date: December 12, 2002
    Applicant: Gunhee JANG
    Inventors: Gunhee Jang, Junghwan Chang, Kyungsu Kim