Issued Patents All Time
Showing 1–10 of 10 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 6771066 | Printed circuit fluxgate sensor for magnetic gradient detection device | — | 2004-08-03 |
| 6304163 | Radially magnetized plastic pipe | — | 2001-10-16 |
| 5206065 | Methods, apparatus and devices relating to magnetic markers for elongated hidden objects | Erick O. Schonstedt | 1993-04-27 |
| 5173139 | Method for providing magnetic markers on elongated hidden objects | Erick O. Schonstedt | 1992-12-22 |
| 5122750 | Methods employing permanent magnets for marking, locating, tracing and identifying hidden objects such as buried fiber optic cables | Charles R. Upton, Erick O. Schonstedt, Bradley L. Osman | 1992-06-16 |
| 5114517 | Methods, apparatus and devices relating to magnetic markers for elongated hidden objects | Erick O. Schonstedt | 1992-05-19 |
| 5017873 | Methods and apparatus employing permanent magnets for marking, locating, tracing and identifying hidden objects such as buried fiber optic cables | Charles R. Upton, Erick O. Schonstedt, Bradley L. Osman | 1991-05-21 |
| 5006806 | Methods and apparatus employing permanent magnets for marking, locating, tracing and identifying hidden objects such as burried fiber optic cables | Charles R. Upton, Erick O. Schonstedt, Bradley L. Osman | 1991-04-09 |
| 4818944 | Magnetic locating and tracing system and method using dual-antenna transmitter to distinguish between concealed adjacent objects | — | 1989-04-04 |
| 4639674 | Apparatus and method employing extraneous field compensation for locating current-carrying objects | — | 1987-01-27 |