Issued Patents All Time
Showing 1–14 of 14 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 11534849 | Light weight cordless stud welder | Scott J. Schraff, Stephen D. Brooks, Jeffrey Krupp | 2022-12-27 |
| 10894296 | Light weight cordless stud welder | Scott J. Schraff, Stephen D. Brooks, Jeffrey Krupp | 2021-01-19 |
| 10279415 | Two-stage switch-mode power supply for drawn-arc stud welding | Christopher Hsu | 2019-05-07 |
| 8410399 | Capacitor charge and discharge circuit for fastener welding | Christopher Hsu, Jeffrey Krupp | 2013-04-02 |
| 6657163 | System and method for selective application of power to welding equipment | George D. Blankenship | 2003-12-02 |
| 6504132 | Electric arc welder for variable AC input | — | 2003-01-07 |
| 6177645 | Electric arc welder and plasma cutter | William T. Matthews | 2001-01-23 |
| 6055161 | Switching type power supply for arc welding | Lifeng Luo | 2000-04-25 |
| 6023037 | Electric ARC welder and plasma cutter | William T. Matthews | 2000-02-08 |
| 4897522 | Output control circuit for inverter | Dale L. Bilczo, Michael J. Kurchak | 1990-01-30 |
| 4380746 | Pulse modulator using capacitor charging and discharging circuits | Shan C. Sun | 1983-04-19 |
| 4293886 | Network protector relay | David R. Smith, Shan C. Sun | 1981-10-06 |
| 4275429 | Protective relay apparatus | Shan C. Sun | 1981-06-23 |
| 4208687 | Protective relay apparatus | Shan C. Sun | 1980-06-17 |