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. 26, 1980
Filed:
Aug. 17, 1978
Tyman H Fikse, Seattle, WA (US);
The Robbins Company, Seattle, WA (US);
Abstract
An earth digging tool is mounted on the head of a tripod, the legs of which are double-acting hydraulic cylinders. The rear ends of the cylinders are connected to a rotor which is supported in a tunneling shield for rotation about an axis extending longitudinally of the tunnel. The cylinders are selectively extended and retracted for the purpose of moving the cutting tool forwardly and rearwardly and also up and down and sideways. The entire excavator is rotated for changing the sideways attitude of the digging tool. Universal joints are provided at both ends of each hydraulic cylinder, for substantially isolating them from bending moments and torque. A telescopic torque tube assembly is interconnected between the cutting tool mounting head and a gimbal carried by the rotor. The torque tube carries the bending moments and torque loads and transmits them back to the rotor.