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Inventor

David Armstrong

Inventor
Tulsa, OK, US

Overview

4→
Patents
1981–2008
Patent span
Performing operations
Primary field (CPC B)

Patents· 4 as inventor

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

E21Bprimary
E21BEarth or rock drilling29%
B29CShaping or joining of plastics14%
B29LIndexing scheme associated with subclass b29c, relating to particular articles14%
B31FMechanical working or deformation of paper, cardboard or material worked in a manner analogous to paper14%
B60NSeats specially adapted for vehicles14%
Y10TTechnical subjects covered by former us classification14%
PatentTitleYear
7,328,750'Sealing plug and method for removing same from a well'20086,926,086'Method for removing a tool from a well'20054,856,848'Manual headrest'19894,264,390'Method and apparatus for making pipe sections in materials'1981

Career & activity timeline

Assembled from patent assignee/location history and declaration credentials.

1981–1989Patents assigned to GEN MOTORS CORP (2)· patent assignee history
1981Based in Royal Oak, MI, US· patent location history
1989Based in Rochester, MI, US· patent location history
2005–2008Patents assigned to HALLIBURTON ENERGY SERV INC (2)· patent assignee history
2005Based in Rock Springs, WY, US· patent location history
2008Based in Tulsa, OK, US· patent location history

Inventor activity

Assignee and location history derived from the patent record.

Assignees
AssigneePatentsSpan
GEN MOTORS CORP21981–1989
HALLIBURTON ENERGY SERV INC22005–2008
Locations
LocationPatentsSpan
Tulsa, OK, US12008
Rock Springs, WY, US12005
Rochester, MI, US11989
Royal Oak, MI, US11981