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:
Aug. 21, 2012
Filed:
Jun. 02, 2011
Chihiro Hayashi, Sendai, JP;
Chihiro Hayashi, Sendai, JP;
Sumitomo Metal Industries, Ltd., Osaka, JP;
Abstract
A method of producing an ultrathin-wall metal tube by a cold drawing method includes a diameter-expanding drawing method, in which an entry solid die, the diameter of which increases, remains constant or decreases from the engaging entry side toward the finishing exit side, and a delivery solid die, the diameter of which decreases at least in the vicinity of the engaging entry, are arranged in series and in an abutting relation on the same pass line. A tapered plug, the diameter of which increases from the engaging entry side toward the finishing exit side, floats along the pass line, whereby in the entry solid die region, the wall thickness is reduced while the mid-wall diameter of a hollow shell is being expanded between the solid die and the plug, and in the delivery solid die region, the tapered plug floats by performing reduction working of the outside diameter.