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:
Mar. 20, 1990
Filed:
Mar. 10, 1989
Other;
Abstract
The drawing tool comprises a hydraulic element for deriving from the movement of the blank holder a simultaneous, oppositely directed movement of the drawing punch. The hydraulic element comprises a centrally disposed working piston, an annular piston, which surrounds that working piston, and a cylinder, which surrounds the annular piston. The working piston and the annular piston are adapted to be supplied with pressure fluid from first and second cylinder chambers which are hydraulically separated from each other and which are adapted to communicate with each other under the control of at least two alternative flow paths, which differ in hydraulic design so that they cause pressure changes on different pressure levels to be effected in the second cylinder chamber. A pressure detector detects the pressure of the fluid in the cylinder chambers and enables an alternative flow path in response to a rise of the pressure above a predetermined limit. As a result, a low-cost, compact tool has been provided, which can be used to make even parts which can be drawn only with great difficulty owing to their desired final shape and/or the material from which they are made.
Data source: USPTO (United States Patent and Trademark Office) public patent records. Weekly synchronization. How IDiyas builds this profile