LexDanaLexDanabeta
Inventor

Henry DO

Inventor
US

Overview

3→
Patents
2021–2023
Patent span
Fixed constructions
Primary field (CPC E)

Patents· 3 as inventor

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

E21Bprimary
E21BEarth or rock drilling50%
F04BPositive-displacement machines for liquids25%
F16HGearing25%
PatentTitleYear
11,852,127Retainer assembly for pump and methods202311,421,479Power swivel and lubrication system202211,136,826Guidance systems and apparatus for power swivel2021

Career & activity timeline

Assembled from patent assignee/location history and declaration credentials.

2021–2022Patents assigned to NAT OILWELL VARCO LP (2)· patent assignee history
2021–2023Based in US· patent location history
2023Patents assigned to SPM OIL & GAS INC (1)· patent assignee history

Inventor activity

Assignee and location history derived from the patent record.

Assignees
AssigneePatentsSpan
NAT OILWELL VARCO LP22021–2022
SPM OIL & GAS INC12023
Locations
LocationPatentsSpan
US32021–2023