EP-4656303-B1 - METHOD AND MACHINE ARRANGEMENT FOR PRODUCING A PROFILE ON A PLASTICALLY DEFORMABLE WORKPIECE BY AXIAL FORMING

EP4656303B1EP 4656303 B1EP4656303 B1EP 4656303B1EP-4656303-B1

Inventors

Keuerleber, Alexander
Combe, Aaron
Wachter, Jörg
JANDT, Max Olaf
HEINRICHS, SERJOSHA

Dates

Publication Date: 20260513
Application Date: 20240527

Claims (15)

A method for producing a workpiece-side profile on a plastically deformable, preferably cylindrical, workpiece (2) by axial forming, • wherein a forming process is carried out, during which a relative movement between a shaping tool profile provided on a forming tool (3) and the workpiece (2) to be formed is carried out to produce the workpiece-side profile having a workpiece-side profile length (L), • wherein, when the forming process is in progress, - an oscillating relative movement between the shaping tool profile and the workpiece (2) to be formed is carried out during the relative movement between the shaping tool profile and the workpiece (2) to be formed, in which oscillating relative movement a forming stroke and a return stroke in the opposite direction to the forming stroke are alternately carried out, - the shaping tool profile produces the workpiece-side profile on the workpiece (2) with a partial length of the workpiece-side profile length (L) during the forming stroke of the oscillating relative movement, and - the shaping tool profile moves during the return stroke of the oscillating relative movement along at least part of the partial length of the workpiece-side profile length (L) produced during the preceding forming stroke, and - a variation is made with regard to the oscillating relative movement between the shaping tool profile and the workpiece (2) to be formed, characterized in that the forming process is controlled by means of a programmable numerical controller (12) which, if an actual geometry of a workpiece-side profile produced in a forming process preceding the forming process deviates from a target geometry of the workpiece-side profile, is designed to store control parameters, on the basis of which parameters a variation is made when the forming process is in progress with regard to the oscillating relative movement between the shaping tool profile and the workpiece (2) to be formed, on the basis of which variation the actual geometry of the workpiece-side profile produced in the forming process corresponds to the target geometry of the workpiece-side profile or at least approximates the target geometry of the workpiece-side profile, • wherein a relative movement between a shaping tool profile provided on a forming tool (3) and a workpiece (2), preferably a cylindrical workpiece, to be formed is carried out during the previous forming process in order to produce the workpiece-side profile with the workpiece-side profile length (L), wherein the forming tool (3) of the previous forming process and the forming tool (3) of the forming process are of the same kind or identical, and wherein the workpiece (2) of the previous forming process and the workpiece (2) of the forming process are of the same kind or identical, • wherein, when the preceding forming process was in progress, - an oscillating relative movement between the shaping tool profile and the workpiece (2) to be formed is carried out during the relative movement between the shaping tool profile and the workpiece (2) to be formed, in which oscillating relative movement a forming stroke and a return stroke in the opposite direction to the forming stroke are alternately carried out, - the shaping tool profile produces the workpiece-side profile on the workpiece (2) with a partial length of the workpiece-side profile length (L) during the forming stroke of the oscillating relative movement, and - the shaping tool profile moves during the return stroke of the oscillating relative movement along at least part of the partial length of the workpiece-side profile length (L) produced during the preceding forming stroke, • wherein the preceding forming process is controlled by means of a numerical controller (12) in which control parameters for controlling the preceding forming process that was in progress with respect to the oscillating relative movement between the shaping tool profile and the workpiece (2) to be formed are stored, and • wherein, after completion of the previous forming process, the actual geometry of the workpiece-side profile produced in the previous forming process is determined and compared with the target geometry of the workpiece-side profile.
The method according to claim 1, characterized in that the actual geometry of the workpiece-side profile produced in the preceding forming process and the actual geometry of the workpiece-side profile produced in the forming process are determined by measuring the workpiece-side profile produced in the preceding forming process and the workpiece-side profile produced in the forming process.
The method according to any one of the preceding claims, characterized in that the preceding forming process in progress is uniform with respect to the oscillating relative movement between the shaping tool profile and the workpiece (2) to be formed.
The method according to claim 1 or 2, characterized in • that , during the preceding forming process in progress, a variation is made with respect to the oscillating relative movement of the shaping tool profile and the workpiece (2) to be formed, and • that the variation made when the forming process is in progress with respect to the oscillating relative movement between the shaping tool profile and the workpiece (2) to be formed differs from the variation made in the preceding forming process in progress.
The method according to any one of the preceding claims, characterized in • that the preceding forming process is carried out as a trial forming process in which the workpiece-side profile is produced on a test workpiece provided as the workpiece (2) to be formed, and • that the forming process is carried out as a manufacturing process in which the workpiece-side profile is produced on a workpiece (2) that is of the same kind as the test workpiece of the forming process.
The method according to any one of the preceding claims, characterized in that , during the forming process and during the preceding forming process, a shaping toothing profile provided on the forming tool (3) as a shaping tool profile and the workpiece (2) to be formed are moved by means of the relative movement to produce a workpiece-side profile designed as a workpiece-side toothing profile having a workpiece-side toothing length as the workpiece-side profile length (L), • wherein the shaping toothing profile engages in the workpiece (2) to be formed during the forming stroke of the oscillating relative movement and produces the workpiece-side toothing profile on the workpiece (2) that has a partial length of the workpiece-side toothing length, and • wherein the shaping toothing profile moves during the return stroke of the oscillating relative movement along at least part of the partial length of the workpiece-side toothing length produced during the preceding forming stroke.
The method according to any one of the preceding claims, characterized in that the variation carried out when the forming process is in progress and, where applicable, the variation carried out during the preceding forming process in progress with respect to the oscillating relative movement between the shaping tool profile and the workpiece (2) to be formed is carried out on the basis of a process-relevant property of the workpiece to be formed.
The method according to claim 7, characterized in that the variation carried out when the forming process is in progress and, where applicable, the variation carried out during the preceding forming process in progress with respect to the oscillating relative movement between the shaping tool profile and the workpiece (2) to be formed is carried out on the basis of the rigidity of the workpiece (2) to be formed.
The method according to claim 7 or claim 8, characterized in that the variation made when the forming process is in progress and, where applicable, the variation made during the preceding forming process in progress with respect to the oscillating relative movement between the shaping tool profile and the workpiece (2) to be formed is carried out on the basis of the material of the workpiece (2) to be formed.
The method according to any one of the preceding claims, characterized in that the variation carried out when the forming process is in progress and, where applicable, the variation carried out during the preceding forming process in progress with respect to the oscillating relative movement between the shaping tool profile and the workpiece (2) to be formed is carried out on the basis of at least one forming parameter.
The method according to any one of the preceding claims, characterized in that the variation with respect to the oscillating relative movement between the shaping tool profile and the workpiece (2) to be formed is carried out when the forming process is in progress and, where applicable, during the preceding forming process in progress by varying the size of the forming stroke and/or the size of the return stroke and/or the frequency of the oscillating relative movement.
The method according to any one of the preceding claims, characterized in that the variation with respect to the oscillating relative movement of the shaping tool profile and the workpiece (2) to be formed is carried out when the forming process is in progress and, where applicable, during the preceding forming process in progress by performing the oscillating relative movement as part of the relative movement of the shaping tool profile and the workpiece (2) to be formed and by performing a unidirectional relative movement between the shaping tool profile and the workpiece (2) to be formed in addition to the oscillating relative movement as a further part of the relative movement between the shaping tool profile and the workpiece (2) to be formed, wherein the shaping tool profile produces the workpiece-side profile on the workpiece (2) with a partial length of the workpiece-side profile length (L) during the unidirectional relative movement.
The method according to claim 12, characterized in • that the shares of the oscillating relative movement and the unidirectional relative movement in the relative movement between the shaping tool profile and the workpiece (2) to be formed are variably determined, and/or • that the order of the oscillating relative movement and the unidirectional relative movement is variably determined.
The method according to at least claim 12, characterized in • that the oscillating relative movement of the shaping tool profile and the workpiece (2) to be formed comprises a plurality of partial oscillating relative movements, wherein a unidirectional relative movement is carried out between two oscillating partial relative movements, and • that the variation with respect to the oscillating relative movement is carried out when the forming process is in progress and, where applicable, during the preceding forming process in progress by varying the forming process in progress and, where applicable, the preceding forming process in progress with respect to at least one of the partial oscillating relative movements.
A mechanical arrangement for carrying out the method according to claim 1, having a forming machine (1) which has a forming drive (5) designed to carry out, during a forming process, a relative movement between a shaping tool profile provided on a forming tool (3) of the forming machine (1) and a workpiece (2), preferably a cylindrical workpiece, to be formed, in order to produce a workpiece-side profile having a workpiece-side profile length (L), • wherein a programmable numerical drive controller (12) is provided for the forming drive (5), which is designed to control the forming drive (5) by control parameters being storable in the drive controller (12), on the basis of which parameters an oscillating relative movement between the shaping tool profile and the workpiece (2) to be formed is carried out when the forming process is in progress when the shaping tool profile moves relative to the workpiece (2) to be formed, in which oscillating relative movement a forming stroke and a return stroke in the opposite direction to the forming stroke are alternately carried out, • wherein the shaping tool profile produces the workpiece-side profile on the workpiece (2) with a partial length of the workpiece-side profile length (L) during the forming stroke of the oscillating relative movement, and • wherein the shaping tool profile moves during the return stroke of the oscillating relative movement along at least part of the partial length of the workpiece-side profile length (L) produced during the preceding forming stroke, • wherein the drive controller (12) is designed to store control parameters for the forming process, on the basis of which parameters a variation is carried out when the forming process is in progress with regard to the oscillating relative movement between the shaping tool profile and the workpiece (2) to be formed, characterized in • that the forming drive (5) of the forming machine (1) is designed to carry out the forming process after a previous forming process and to perform a relative movement between a shaping tool profile provided on a forming tool (3) of the forming machine (1) and a workpiece (2), preferably a cylindrical workpiece, to be formed during the previous forming process in order to produce the workpiece-side profile having the workpiece-side profile length (L), wherein the forming tool (3) of the previous forming process and the forming tool (3) of the forming process are of the same kind or identical, and wherein the workpiece (2) of the previous forming process and the workpiece (2) of the forming process are of the same kind or identical, • that the drive controller (12) is designed to control the forming drive (5) by control parameters being storable in the drive controller (12), on the basis of which parameters, when the preceding forming process is in progress, an oscillating relative movement between the shaping tool profile and the workpiece (2) to be formed is performed during the relative movement between the shaping tool profile and the workpiece (2) to be formed, in which oscillating relative movement a forming stroke and a return stroke in the opposite direction to the forming stroke are alternately carried out, - wherein the shaping tool profile produces the workpiece-side profile on the workpiece (2) with a partial length of the workpiece-side profile length (L) during the forming stroke of the oscillating relative movement, and - wherein the shaping tool profile moves during the return stroke of the oscillating relative movement along at least part of the partial length of the workpiece-side profile length (L) produced during the preceding forming stroke, • that a measuring and evaluation device (16) is provided, by means of which, after completion of the preceding forming process, an actual geometry of the workpiece-side profile produced during the preceding forming process can be determined and compared with a target geometry of the workpiece-side profile, wherein the forming process is carried out by means of the forming machine (1) if the actual geometry of the workpiece-side profile produced during the preceding forming process deviates from the target geometry of the workpiece-side profile, and • that , if the actual geometry of the workpiece-side profile produced in the preceding forming process deviates from the target geometry of the workpiece-side profile, the drive controller (12) is designed to store control parameters for the forming process, on the basis of which control parameters a variation is made when the forming process is in progress with regard to the oscillating relative movement between the shaping tool profile and the workpiece (2) to be formed, due to which variation the actual geometry of the workpiece-side profile produced during the forming process corresponds to the target geometry of the workpiece-side profile or at least approximates the target geometry of the workpiece-side profile.

Description

The invention relates to a method for producing a workpiece-side profile on a plastically deformable, preferably cylindrical, workpiece by axial forming, wherein a forming process is carried out, in the course of which a relative movement of a forming tool profile provided on a forming tool and the workpiece to be formed is performed to produce the workpiece-side profile with a workpiece-side profile length, during the ongoing forming process In the relative movement of the forming tool profile and the workpiece to be formed, an oscillating relative movement of the forming tool profile and the workpiece to be formed is carried out, in which a forming stroke and a return stroke directed opposite to the forming stroke are carried out alternately, the forming tool profile, during the forming stroke of the oscillating relative movement on the workpiece, generates the workpiece-side profile with a partial length of the workpiece-side profile length and the forming tool profile moves along at least a part of the partial length of the workpiece-side profile length generated during the preceding forming stroke during the return stroke of the oscillating relative movement and a variation is made regarding the oscillating relative movement of the forming tool profile and the workpiece to be formed. The invention also relates to a mechanical arrangement for producing a workpiece-side profile on a plastically deformable, preferably cylindrical, workpiece by axial forming, with a forming machine which has a forming drive which is designed to generate a relative movement in a forming process of a forming tool profile provided on a forming tool of the forming machine and of a workpiece to be formed, preferably cylindrical workpiece to produce a workpiece-side profile with a workpiece-side profile length, wherein a programmable numerical drive control is provided for the forming drive, which is designed to control the forming drive by allowing control parameters to be stored in the drive control, according to which, in the ongoing forming process, an oscillating relative movement of the forming tool profile and the workpiece to be formed is carried out during the relative movement of the forming tool profile and the workpiece to be formed, in which a forming stroke and a return stroke directed opposite to the forming stroke are carried out alternately, wherein the forming tool profile generates the workpiece-side profile with a partial length of the workpiece-side profile length during the forming stroke of the oscillating relative movement and wherein the forming tool profile moves along at least a part of the partial length of the workpiece-side profile length generated during the preceding forming stroke during the return stroke of the oscillating relative movement and wherein the drive control is designed to store control parameters for the forming process, based on which a variation is made in the ongoing forming process with regard to the oscillating relative movement of the forming tool profile and the workpiece to be formed. Axial forming is a process of extrusion. In extrusion, a forming tool exerts a compressive force on the workpiece to be formed, which is dimensioned such that the yield strength of the workpiece material is exceeded. For this purpose, the forming tool and the workpiece to be formed are subjected to a feed force against each other. The state of the art, as defined by the type of product, is disclosed in WO 2008017358 A1 . In the prior art, a workpiece to be formed and a forming die mounted on the workpiece are moved relative to each other along a feed axis by means of a feed device. Due to the resulting When the workpiece is actuated by the forming die, the workpiece material begins to flow. During an axial relative movement of the forming die and the workpiece, i.e., along the feed axis, the workpiece is formed by the forming die. This relative movement is non-uniform. A frequency generator causes the feed mechanism to produce an oscillating relative movement of the forming die and the workpiece to be formed, during which they move alternately towards and away from each other until the workpiece has been formed over a predetermined length. The feed mechanism is modulated by the frequency generator in such a way that the stroke lengths of the forward strokes and/or the reverse strokes of at least two successive forming steps, each consisting of a forward stroke and a reverse stroke, are different. Further state of the art is known from WO 2019137702 A1 This publication discloses a method and a device for manufacturing hollow, internally cooled valves. The cross-section of a stem section of a valve preform is tapered by pressing the stem section of the valve preform into a die using a pressing device with an oscillating motion. The stroke length of the working strokes is varied. Starting from the prior art of the generic type, the object of the present invention is to provide a method and a mac