Issued Patents 1994
Showing 1–1 of 1 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 5375657 | Chain long-stroke oil-well pumping unit | Chaoying Shi, Kaili Song, Xinhua Li, Juanhuan Yang, Quingkun Zeng | 1994-12-27 |
Showing 1–1 of 1 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 5375657 | Chain long-stroke oil-well pumping unit | Chaoying Shi, Kaili Song, Xinhua Li, Juanhuan Yang, Quingkun Zeng | 1994-12-27 |