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Inventor

Rudolf Roper

Inventor
Dortmund, DE

Overview

2→
Patents
1985–1992
Patent span
Fixed constructions
Primary field (CPC E)

Patents· 2 as inventor

Public. Assignee & technology derived from the patent record. Each patent links to its LexDana page.

E21Bprimary
E21BEarth or rock drilling67%
Y10TTechnical subjects covered by former us classification33%
PatentTitleYear
5,156,222'Directional drilling tool apparatus and method'19924,519,574'Auxiliary controlled valve disposed in a drilling string'1985

Career & activity timeline

Assembled from patent assignee/location history and declaration credentials.

1985Patents assigned to CHRISTENSEN INC NORTON (1)· patent assignee history
1985–1992Based in Dortmund, DE· patent location history
1992Patents assigned to BAKER HUGHES INC (1)· patent assignee history

Inventor activity

Assignee and location history derived from the patent record.

Assignees
AssigneePatentsSpan
BAKER HUGHES INC11992
CHRISTENSEN INC NORTON11985
Locations
LocationPatentsSpan
Dortmund, DE21985–1992