The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jan. 21, 1992
Filed:
Nov. 13, 1990
Applicant:
Inventors:
Assignee:
Hilti Aktiengesellschaft, Furstentum, LI;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
E21B / ;
U.S. Cl.
CPC ...
175403 ; 175411 ; 285286 ; 285287 ;
Abstract
A hollow drill (1) is made up of a tubular carrier part (2), a cutter part (3) and an intermediate part (4) extending between the carrier part (2) and cutter part (3). The intermediate part (4) is rigidly fixed to the cutter part (3). The carrier part (2) and the intermediate part (4) have axially extending extensions (11, 12) which telescope one into the other with solder (8) located between and removably connecting the extensions (11, 12) together.