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:
Jul. 25, 2000
Filed:
Nov. 03, 1998
Kiyoshi Miya, Tokyo, JP;
Yoshihiro Tanaka, Tokyo, JP;
Obayashi Corporation, Osaka, JP;
Abstract
The present invention relates to a tail structure of a shield driving machine, and in particular relates to an improvement technique of the tail sealing portion of this type of shield driving machine, in order to eliminate wearing of the tail seal. The tail structure has a first tail seal 12 and a second tail seal 14. The first tail seal 12 is provided with a tail ring 12a, a seal tube 12b and packing 12c, and the tail ring 12a is secured movably in the axial direction of a skin plate 10. The packing 12c is pressure-fitted to segments 11 in line with enlargement of the seal tube 12b and is spaced from the segments 11 in line with reduction of the seal tube 12b. The second tail seal 14 is provided with a seal tube 14a and packing 14b, wherein the packing 14b is pressure-fitted to the segments 11 in line with enlargement of the seal tube 14a and is spaced from the segments 11 in line with reduction of the seal tube 14b. When excavating, the packing 14b causes the first tail seal 12 to be pressure-fitted to the segments 11 without moving the first tail seal 12, and causes the second tail seal 14 to be spaced from the segments 11.