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:
Sep. 13, 1977
Filed:
Mar. 12, 1976
Applicant:
Inventors:
Teruo Yahiro, Tokyo, JA;
Hiroshi Yoshida, Tokyo, JA;
Assignees:
Chemical Grout Company, Ltd., Tokyo, JA;
Kajima Corporation, Tokyo, JA;
Primary Examiner:
Int. Cl.
CPC ...
E21B / ;
U.S. Cl.
CPC ...
175 67 ; 37 78 ; 175422 ; 299 17 ;
Abstract
The method of digging by piercing soil and rock with a jet of liquid discharged at high velocity from a nozzle together with high-velocity air jets discharged from another nozzle arranged concentrically around the liquid nozzle, characterized by the velocity of the air jets being at least half the velocity of sound.