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Inventor

Yiji Xu

Inventor
Shandong, CN

Overview

1→
Patents
1991
Patent span
Fixed constructions
Primary field (CPC E)

Patents· 1 as inventor

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

E21Bprimary
E21BEarth or rock drilling100%
PatentTitleYear
5,072,796'Boring bit'1991

Career & activity timeline

Assembled from patent assignee/location history and declaration credentials.

1991Patents assigned to UNIV PETROLEUM CHINA (1)· patent assignee history
1991Based in Shandong, CN· patent location history

Inventor activity

Assignee and location history derived from the patent record.

Assignees
AssigneePatentsSpan
UNIV PETROLEUM CHINA11991
Locations
LocationPatentsSpan
Shandong, CN11991