Inventor
Donald E. Ritchie
Inventor
Houston, TX, US
Overview
Patents· 2 as inventor
Public. Assignee & technology derived from the patent record. Each patent links to its LexDana page.
E21Bprimary
E21BEarth or rock drilling100%
Career & activity timeline
Assembled from patent assignee/location history and declaration credentials.
1987–1989Patents assigned to DRESSER IND (2)· patent assignee history
1987–1989Based in Houston, TX, US· patent location history
Inventor activity
Assignee and location history derived from the patent record.
Assignees
| Assignee | Patents | Span |
|---|---|---|
| DRESSER IND | 2 | 1987–1989 |
Locations
| Location | Patents | Span |
|---|---|---|
| Houston, Texas, US | 2 | 1987–1989 |