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:
Dec. 21, 1982
Filed:
Jan. 12, 1981
Masao Nishihara, Kyoto, JP;
Yoshinori Fukui, Hyogo, JP;
Yoshio Kitamura, Hyogo, JP;
Yoshiyuki Kamikawa, Kobe, JP;
Haruki Azuma, Kobe, JP;
Kobe Steel, Limited, Kobe, JP;
Abstract
Disclosed is a method and apparatus for cold-working annular workpieces by applying thereto an internal fluid pressure to cause an enlargement of the diameter thereof through plastic deformation, in which the openings at opposite ends of an annular workpiece are closed by a pair of presser plates through packings which are radially expansible along with the annular workpiece. The contacting surface pressure of the packings and presser plates are controlled to a predetermined value by an arithmetic unit operating on detected values of a main pressure acting internally on the annular workpiece, an auxiliary pressure pressingly holding the presser plates against the respective packings and varitions in the shape of the annular workpiece undergoing the plastic deformation.