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:
Feb. 14, 1989
Filed:
Nov. 10, 1987
Yasunori Kondo, Kakogawa, JP;
Kawasaki Jukogyo Kabushiki Kaisha, Hyogo, JP;
Abstract
A tunnel excavator has a substantially tubular shield having rotatably mounted on one end a motor-driven cutting disk rotatably carrying a multiplicity of roller cutters. The shield is comprised of a head section having front anchors in addition to the cutting disk, an inner section telescopically nested in the head section and constrained to only axial displacement relative to the same, and a tail section having rear anchors and coupled to the inner section for both bending and rolling movements relative to the same. Hydraulic push jacks act between the head and tail shield sections for advancing the shield. A pair of hydraulically independent antirolling jacks are connected between the inner and tail shield sections so as to enable the tail shield section, which is anchored during excavation, to bear against the rolling of the head shield section.