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:
Oct. 21, 1980
Filed:
Sep. 05, 1978
Bernt S Liljekvist, Sandviken, SE;
Anders E Persson, Sandviken, SE;
Sandvik Aktiebolag, Sandviken, SE;
Abstract
A reamer bit for raise boring in rock, of the type comprising a body on which a number of rolling cutters with cutting inserts are rotatably mounted for contact with and disintegration of the rock, and a detachable stem mounted in a central bore on the body and adapted to be received in a pilot hole drilled in advance in the rock. The stem has two cylindrical portions, an upper one of which having a smaller diameter than a lower one thereof. The bore in the body has corresponding upper and lower cylindrical portions surrounding the stem. The upper cylindrical portions of the body and the stem define upper stem restraining surface means. The lower cylindrical portions of the body and the stem define lower stem restraining surface means. The stem at its lower portion is provided with a flange abutting the body from below and supporting it axially. The upper and lower restraining surface means together comprise a substantial axial portion of the part of the stem that is surrounded by the bore. The corresponding surrounding portions of the bore in the body form a close fit with the cylindrical portions on the stem.