LexDanaLexDanabeta
Inventor

Sidney Dantuma JOHNSTON

Inventor
GB

Overview

4→
Patents
2022–2025
Patent span
Mechanical engineering
Primary field (CPC F)

Patents· 4 as inventor

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

E21Bprimary
E21BEarth or rock drilling40%
F42BExplosive charges, e.g. for blasting, fireworks, ammunition20%
B23KSoldering or unsoldering10%
F02KJet-propulsion plants10%
F42CAmmunition fuzes10%
F42DBlasting10%
PatentTitleYear
12,297,709Tool for severing a downhole tubular by a stream of combustion products202511,359,450Downhole tool with a propellant charge202211,332,993Cutting tool202211,215,024Tool with propellant sections2022

Career & activity timeline

Assembled from patent assignee/location history and declaration credentials.

2022–2025Patents assigned to SPEX CORP HOLDINGS LTD (2)· patent assignee history
2022Patents assigned to SPEX CORPORATE HOLDINGS LTD (2)· patent assignee history
2022Patents assigned to SPEX ENGINEERING UK LTD (1)· patent assignee history
2022–2025Based in GB· patent location history

Inventor activity

Assignee and location history derived from the patent record.

Assignees
AssigneePatentsSpan
SPEX CORP HOLDINGS LTD22022–2025
SPEX CORPORATE HOLDINGS LTD22022
SPEX ENGINEERING UK LTD12022
Locations
LocationPatentsSpan
GB42022–2025