Issued Patents 1989
Showing 1–4 of 4 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 4886939 | Cable sealing device and method | — | 1989-12-12 |
| 4866214 | Service cable for a subsoil penetrating tool and method of preventing rotation of the cable when in use | — | 1989-09-12 |
| 4858703 | Self-propelled subsoil penetrating tool system | — | 1989-08-22 |
| 4842207 | Device for detecting and measuring the tension on a cable | — | 1989-06-27 |