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. 17, 1990
Filed:
Jan. 31, 1989
Otto Herndl, Leverkusen, DE;
Werner Schiller, Bergisch-Gladbach, DE;
Abstract
A multi-ram forging assembly has a piston-cylinder unit for driving each ram carrying a forging tool wherein at least two diametrically opposed forging unit simultaneously act on a workpiece. Each piston-cylinder unit comprises a pressurized inlet chamber for containing a hydraulic pressure fluid at a predetermined pressure behind a piston movably disposed in the cylinder. The piston includes a front-end ram carrying a forging tool. A valve including a valve seat member is disposed on the piston at a rear side opposite to the front-end ram. A valve cone cooperates with the valve seat member to provide a closed position and an open position for the valve. An actuator is connected to move the valve cone between the closed and open positions. The piston includes a passage bore extending from the valve seat member to a pressure fluid discharge chamber connected to a hydraulic pressure fluid reservoir container providing a pressureless discharge of the pressure fluid medium. A piston return pressure chamber is located within the cylinder to cause the return of the piston under the action of a pressure fluid having a preselected predetermined pressure maintained within the piston return pressure chamber.