Patent ID: 6708548
Filing Date: 2004-03-23
Classification: B21D,B21J,B21K

Abstract:
A shape-forming device for shape-forming the end region of a workpiece, comprising:a housing having one end in which a workpiece which is to be shape-formed can be received; a plurality of jaws disposed in the housing, the jaws being operable to exert a compressive retaining force on a workpiece received in the housing such that the workpiece is releasably retained in a fixed position relative to the housing while shape-forming work is performed on the workpiece; a first hydrodynamically actuable force transmission element operable to place the workpiece in compression; a compression surface disposed axially intermediate the one end of the housing and the first force transmitting element and movable in a shape-form working axial direction toward the one end of the housing to engage a workpiece retained by the jaws in the housing; a second hydrodynamically actuable force transmission element, the first force transmitting element and the second force transmitting element being disposed in the housing with the first force transmitting element intermediate the one end of the housing and the second force transmitting element, the first force transmitting element having a bore through which the second force transmitting element extends such that the second force transmitting element is axially displaceable relative to the first force transmitting element and the compression surface being movably guided by the first force transmitting element and engageable by the second force transmitting element such that the second force transmitting element applies a force on the compression surface to move the compression surface in the shape-form working direction, the first force transmitting element and the second force transmitting element being movable in the shape-form working axial direction from respective start positions toward the one end of the housing and in an opposite axial direction along which the first force transmitting element and the second force transmitting element move to return to their respective start positions; a first pressure space formed between the first force transmitting element and the second force transmitting element, the first pressure space being communicated via a first pressure connector with a pressure medium source; and a second pressure space communicated via a second pressure connector with a pressure medium source, the second pressure space being disposed relative to the second force transmitting element such that the introduction of a pressure medium into the second pressure space effects axial movement of the second force transmitting element in the shape-form working axial direction, the shape-forming device being operable to force the compression surface against the retained workpiece in a shape-form working manner such that the workpiece is shape-formed via an operation in which a pressure medium is introduced into the second pressure space to effect movement of the second force transmitting element along the shape-form working axial direction at the same time that a pressure medium in the first pressure space is maintained such that an axial propulsion force generated by the axial movement of the second force transmitting element is transmitted to the first force transmitting element in a manner which effects corresponding movement of the first force transmitting element in the shape-form working axial direction, whereupon the compression surface eventually engages a retained workpiece as the axial movement of the first force transmitting element continues and, following engagement of the compression surface with the retained workpiece, the axial propulsion force on the first force transmitting element is maintained until a desired overpressure develops in the first pressure space and, thereafter, the pressure medium from the first pressure space is released such that continued pressure on the second force transmitting element via the pressure medium in the second pressure space effects movement of the second force transmitting element relative to the first force transmitting element so as to thereby apply force on the compression surface and thus effect shape-forming of the retained workpiece.