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:
Apr. 18, 1978
Filed:
Dec. 22, 1976
Walter Hohn, Lunen, DT;
Gewerkschaft Eisenhutte Westfalia, Lunen, DT;
Abstract
A drive shield of a tunnelling apparatus has elongate drive members supported and guided for longitudinal movement in a manner known per se. The drive members are connected to rear members or tails forming a rear shield and fluid concrete is introduced into a reception space within the rear shield to create a permanent lining for the tunnel. The rear members are shaped or profiled to provide recesses which are closed-off over a certain zone with the aid of covers. Reinforcing bars or the like can be inserted into the recesses to become cast into the concrete lining and means for delimiting the front end of the concrete reception space, such as a ring component, engages on the covers which form a smooth continuous bearing surface therefor.