Issued Patents 2021
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 11191404 | Cleaner | Kietak Hyun, Jonguk HER | 2021-12-07 |
| 11160428 | Cleaner | Changgun LEE, Kietak Hyun, Sejin Yook, Sanghee Woo, Seungyoon Noh | 2021-11-02 |
| 11147423 | Dust collector and cleaner having the same | Kietak Hyun, Changgun LEE | 2021-10-19 |
| 11130204 | Field dissimilar metal welding technology for enhanced wear resistant high manganese steel | Andrew J. Wasson, Douglas P. Fairchild, HyunWoo Jin, Xin Yue, IlWook Han +2 more | 2021-09-28 |