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. 11, 1979
Filed:
Sep. 29, 1977
Kozo Ono, Tsuchiura, JP;
Masao Suda, Tsuchiura, JP;
Abstract
In a tunnel boring or shield machine, a method and system for controlling the earth pressure, in which the earth pressure in the chamber of the shield machine body is detected and the detected earth pressure is compared with a reference value to thereby produce a chamber earth pressure deviation signal. In response to the chamber earth pressure deviation signal, means for controlling the amount of conveying earth accumulated in the chamber to the exterior of the machine body and/or means for advancing the shield machine body into the working face are controlled so as to maintain the earth pressure in the chamber within a predetermined range so that the breakdown of the exposed face or earth stratum as well as the rising of the ground are prevented from occurring. In another method and system, the earth pressure at the working face is detected and the detected value is compared with a reference value to produce a signal representing the earth pressure deviation at the working face.