EP0589066B1 - Method for making products by force or pressure influenced drawing processes - Google Patents
Method for making products by force or pressure influenced drawing processes Download PDFInfo
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- EP0589066B1 EP0589066B1 EP19920112315 EP92112315A EP0589066B1 EP 0589066 B1 EP0589066 B1 EP 0589066B1 EP 19920112315 EP19920112315 EP 19920112315 EP 92112315 A EP92112315 A EP 92112315A EP 0589066 B1 EP0589066 B1 EP 0589066B1
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
- B21D—WORKING OR PROCESSING OF SHEET METAL OR METAL TUBES, RODS OR PROFILES WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
- B21D24/00—Special deep-drawing arrangements in, or in connection with, presses
- B21D24/10—Devices controlling or operating blank holders independently, or in conjunction with dies
Definitions
- the invention relates to a method for producing molded parts by means of forming processes influenced by the action of force or pressure, in particular thermoformed sheets for body parts of motor vehicles, by regulating the forming process according to the preamble of patent claim 1.
- a device for controlling or regulating the sheet metal holder force during the drawing process with a hydraulic container - piston - cylinder drive (DE-PS 36 40 50 71), in which to control and regulate the pressures in the sheet metal holder power sets and thus to regulate the sheet metal holder force Proportional or servo valves are provided.
- a sensor is assigned to the sheet metal holder cylinder, which is connected to a control unit which makes the desired pressure change in the sheet metal holder cylinder depending on the respective drawing progress via the proportional or servo valve.
- the valves upstream of the sheet metal cylinders are acted upon by electronic control with switching signals which change the cylinder pressure of the sheet metal holder cylinders several times during the shaping process.
- the drawing path-dependent sheet metal holder pressure corresponds here to a desired curve desired for the deep-drawn part to be produced.
- the setpoint value setting of a test press during tool testing is entered into a control device which adapts the press setting in the course of production to the boundary conditions fluctuating within tolerances which are caused by changes in the sheet metal characteristic values and the surface roughness.
- the tolerance range of the sheet holder force curve lies between the unusable cases in which wrinkling and and constriction or cracks occur.
- a process computer should process the data of the basic machine settings from tool testing, sheet metal value recognition by eddy current methods, sheet metal surface value determination by light-optical measuring methods, lubricant film thickness measurement by capacitive methods, lubricant consistency by refractometer measurement, and the detection of wrinkle measurement Enter the gap between the upper and lower part of the tool and a quality check by structure-borne noise analysis on the equipment and after appropriate measurement data processing for an adaptive control of the sheet metal holder force of the forming step.
- the invention is based on the object of providing a method of the type mentioned at the outset with which it is possible in a relatively simple manner to produce error-free deep-drawn sheets by regulating the forming process.
- this object is achieved by the method steps resulting from the characterizing part of claim 1.
- a tolerance band for the characteristic values of good part and bad part forming processes is determined from calibration forming processes and a reference variable for the movement of the starting material and / or its time derivatives is derived from the tolerance band.
- Further process-relevant signals can be used as additional reference variables, the significance of these signals in relation to the movement of the starting material and / or their time derivatives being determined from calibration measurements when regulating the forming process.
- Another process-relevant signal can be used as an additional command variable for the size of the tool gap.
- further process-relevant signals can be used as the additional reference variables.
- the method according to the invention ensures, from a relatively simple and effective manner, a practically flawless production of pressed parts in the pressing plant by regulating the forming process in such a way that the sheet is drawn into the drawing mold in an operative connection with the movement of the drawing die.
- the movement of the sheet on the hold-down device is measured and regulated via the manipulated variable "hold-down force" so that it corresponds to the movement of the sheet for a good part forming process.
- the tolerance band for a workpiece-specific hold-down force is determined using calibration measurements, which include the characteristic values of good part and bad part forming processes.
- Fig. 1 shows the course of the sheet metal holder force during the forming process for bad part forming processes (wrinkling or tearing) and a good part forming process.
- bad part forming processes wrinkleling or tearing
- a good part forming process In the production of the molded parts by means of the forming process influenced by the action of force or pressure 1, a tolerance band for the characteristic values of the good part and bad part forming processes is determined from calibration forming processes for the movement of the starting material of the workpiece. A reference variable for the movement of the starting material is then derived from the tolerance band.
- the movement of the material can either be measured directly or the material speed can be determined at various points via correlation measurements of the material texture.
- 2 shows a measuring arrangement for direct measurement of the sheet metal position, in which a series of optical triangulation sensors 5 is arranged around the workpiece 1, which is arranged on a hold-down device 2 between a die cushion 3 and a punch 4 of a press, with which the migration of individual points on the edge of the workpiece 1 is specifically observed. A path-time diagram is created for each of these points. Online comparison of the forming process is then possible by comparing the curve profiles with the corresponding data of the IO process.
- 3 shows an arrangement for the inductive measurement of the sheet metal speed, with which the induction of voltages during the movement of a conductor in a magnetic field is used.
- 3a and 3b show a cross section through the press or a view of the hold-down device 2.
- a coil 6 is inserted, which is connected to a DC voltage source 7.
- the arrangement of the two contact pins 8 must be such that the connecting line between the two contact pins 8 is arranged both perpendicular to the magnetic field and to the direction of movement A (see arrow in FIG. 3b) of the material.
- the determination of the movement of the material can also be determined indirectly in the forming process, e.g. by measuring the sheet speed with correlation methods, as can be seen in FIG. 4.
- the material texture is measured at various points on the circuit board 1 by means of the sensors 5 arranged in the hold-down device 2, the signals of which are each displayed on a screen 9.
- the cross-correlation function (KKF) between the two signals is calculated from the corresponding output signals 10 by means of a correlator 11 and displayed on a screen 12. From the position of the main maxima of the cross-correlation functions, the running time of the material and thus the speed of the material can be calculated as a quotient of the sensor distance b and the running time.
- the material texture can be measured by means of interferometric methods, by means of mechanical-inductive methods or by means of non-contact inductive displacement sensors.
- So-called heterodyne profilers can be used for interferometric texture measurement, which are not excessively sensitive to vibration and of which the material surface is slightly affected by two collinear laser beams different frequency is illuminated. If these two laser beams are brought to interference after reflection on the material surface, a phase difference results which is directly dependent on the difference in height of the two light spot locations on the material surface.
- inductive displacement sensors with probe tips are installed in the holding-down device and in the die cushion.
- the resolution of which is in the submicro range the roughness of the material, which is in the range of micrometers, can be suitably scanned. If three sensors are arranged on the corner points of a right-angled triangle, the speed can be recorded vectorially.
- Sensors for contactless inductive displacement measurement usually have a relatively large cross-sectional area, the diameter being in the millimeter range.
- the measurement signal is, however, an integral over this cross-sectional area.
- only sensors can be used whose tactile area has been reduced accordingly, e.g. by converting the coil cores.
Description
Die Erfindung betrifft ein Verfahren zur Herstellung von Formteilen mittels durch Kraft- oder Druckeinwirkung beeinflußter Umformprozesse, insbesondere von Tiefziehblechen für Karosserieteile von Kraftfahrzeugen, durch Regelung des Umformprozesses gemäß dem Oberbegriff des Patentanspruchs 1.The invention relates to a method for producing molded parts by means of forming processes influenced by the action of force or pressure, in particular thermoformed sheets for body parts of motor vehicles, by regulating the forming process according to the preamble of
Ein solches Verfahren geht aus der JP-A-59 159 228 hervor.Such a method is disclosed in JP-A-59 159 228.
Es ist eine Einrichtung zur Steuerung bzw. Regelung der Blechhalterkraft während des Ziehvorgangs mit einem hydraulischen Behälter - Kolben - Zylindertrieb bekannt (DE-PS 36 40 50 71), bei der zur Steuerung und Regelung der Drücke in den Blechhalterkraftgarnituren und damit zur Regelung der Blechhalterkraft Proportional- oder Servorventile vorgesehen sind. Hierbei ist dem Blechhalterzylinder ein Sensor zugeordnet, der mit einem Steuergerät in Verbindung steht, welches die gewünschte Druckänderung im Blechhalterzylinder in Abhängigkeit von dem jeweiligen Ziehfortschritt über das Proportional- oder Servorventil vornimmt.There is a device for controlling or regulating the sheet metal holder force during the drawing process with a hydraulic container - piston - cylinder drive (DE-PS 36 40 50 71), in which to control and regulate the pressures in the sheet metal holder power sets and thus to regulate the sheet metal holder force Proportional or servo valves are provided. In this case, a sensor is assigned to the sheet metal holder cylinder, which is connected to a control unit which makes the desired pressure change in the sheet metal holder cylinder depending on the respective drawing progress via the proportional or servo valve.
Bekannt ist weiterhin ein Verfahren zum Tiefziehen von Platinen, insbesondere von Tiefziehblechen für Karosserieelemente von Kraftfahrzeugen, mittels hydraulischer Tiefziehpressen (DE-OS 37 44 177), wobei die Platine während des durch einen mit einer Matrize zusammenwirken den Stempels eines Pressenstößels hervorgerufenen Verformungsvorgangs an ihren Randbereichen zwischen einer Blechhalterbahn eines Blechhalters und einem Ziehkissen fest eingespannt und der Blechhalterdruck von ventilgesteuerten Blechhalterzylindern aufgebracht werden, die überdies den Bewegungsablauf des Blechhalters bestimmen. Zur Optimierung der Qualität der hergestellten Tiefziehteile werden die den Blechzylindern vorgeschalteten Ventile von einer elektronischen Regelung mit Schaltsignalen beaufschlagt, die den Zylinderdruck der Blechhalterzylinder während des Verformvorgangs mehrfach verändern. Der ziehwegabhängige Blechhalterdruck entspricht hier einer für das jeweils herzustellende Tiefziehteil gewünschten Sollkurve.Also known is a method for deep-drawing of blanks, in particular deep-drawing sheets for body elements of motor vehicles, by means of hydraulic deep-drawing presses (DE-OS 37 44 177), the blank being at its edge regions during the deformation process caused by a die in a press ram firmly clamped between a sheet holder web of a sheet holder and a die cushion and the sheet holder pressure are applied by valve-controlled sheet metal holder cylinders, which also determine the movement sequence of the sheet metal holder. To optimize the quality of the deep-drawn parts produced, the valves upstream of the sheet metal cylinders are acted upon by electronic control with switching signals which change the cylinder pressure of the sheet metal holder cylinders several times during the shaping process. The drawing path-dependent sheet metal holder pressure corresponds here to a desired curve desired for the deep-drawn part to be produced.
Der Einsatz der erwähnten servo -hydraulischen Steuerung zur Beeinflussung des Blechhalterkraftverlaufes in Abhängigkeit vom Ziehweg bei Ziehpressen und Zieheinrichtungen ermöglicht es, den Blechhalterverlauf in den vier Eckpunkten des Werkzeugs durch Vorgabe unterschiedlicher Druckverläufe zu steuern. Nach Überlegungen im Zusammenhang mit der prozeßgesteuerten Preßteilfertigung (Aufsatz "Flexibilisierungspotentiale in der Preßwerktechnik", Dipl.-Ing. H. Petri, Dr.-Ing. V. Thoms, Sindelfingen, 4. Umformtechnisches Kolloquium in Darmstadt des DFB am 13. und 14.03.1991, Tagungsband) sollten die Umformstufen in der Produktion mit einer Kraftregelung unter Berücksichtigung der Randbedingungen ausgerüstet werden, um die Presseeinstellzeit und die Produktionsunterbrechungen zu reduzieren. Die Sollwerteinstellung einer Versuchspresse bei der Werkzeugerprobung wird einer Regeleinrichtung eingegeben, die die Presseneinstellung im Produktionsverlauf den innerhalb von Toleranzen schwankenden Randbedingungen anpaßt, die durch Änderungen der Blechkennwerte und der Oberflächenrauigkeit verursacht werden. Das Toleranzfeld des Blechhalterkraftverlaufs liegt zwischen den unbrauchbaren Fällen, in denen eine Faltenbildung und und eine Einschnürung bzw. Risse auftreten. In verhältnismäßig aufwendiger Weise sollen bei der prozeßgesteuerten Preßteilfertigung einem Prozeßrechner die Daten der Maschinen-Grundeinstellung von der Werkzeugerprobung, einer Blechkennwerterkennung durch Wirbelstromverfahren, einer Blechoberflächenkennwertermittlung durch lichtoptische Meßverfahren, einer Schmierfilmdickenmessung durch kapazitives Verfahren, einer Schmierstoffkonsistenz durch Refraktometermessung, einer Erkennung von Faltenbildung durch Kontrolle des Spaltes zwischen Werkzeugober- und -unterteil und einer Qualitätsprüfung durch Körperschallanalyse am Betriebsmittel eingegeben und nach entsprechender Meßdatenverarbeitung für eine adaptive Regelung der Blechhalterkraft der Umformstufe gesorgt werden.The use of the servo-hydraulic control mentioned to influence the sheet holder force curve as a function of the drawing path in the case of drawing presses and drawing devices makes it possible to control the sheet holder holder course in the four corner points of the tool by specifying different pressure curves. After considerations in connection with the process-controlled production of pressed parts (essay "Flexibility potentials in press technology", Dipl.-Ing. H. Petri, Dr.-Ing. V. Thoms, Sindelfingen, 4th Forming Technology Colloquium in Darmstadt of the DFB on March 13th and 14th .1991, conference proceedings) the forming stages in the production should be equipped with a force control taking into account the boundary conditions in order to reduce the press setting time and the production interruptions. The setpoint value setting of a test press during tool testing is entered into a control device which adapts the press setting in the course of production to the boundary conditions fluctuating within tolerances which are caused by changes in the sheet metal characteristic values and the surface roughness. The tolerance range of the sheet holder force curve lies between the unusable cases in which wrinkling and and constriction or cracks occur. In the case of process-controlled press part production, a process computer should process the data of the basic machine settings from tool testing, sheet metal value recognition by eddy current methods, sheet metal surface value determination by light-optical measuring methods, lubricant film thickness measurement by capacitive methods, lubricant consistency by refractometer measurement, and the detection of wrinkle measurement Enter the gap between the upper and lower part of the tool and a quality check by structure-borne noise analysis on the equipment and after appropriate measurement data processing for an adaptive control of the sheet metal holder force of the forming step.
Der Erfindung liegt die Aufgabe zugrunde, ein Verfahren der eingangs erwähnten Art zur Verfügung zustellen, mit dem auf verhältnismäßig einfache Weise eine fehlerfreie Herstellung von Tiefziehblechen durch Regelung des Umformprozesses möglich wird.The invention is based on the object of providing a method of the type mentioned at the outset with which it is possible in a relatively simple manner to produce error-free deep-drawn sheets by regulating the forming process.
Diese Aufgabe wird erfindungsgemäß durch die aus den Kennzeichen des Patentanspruchs 1 hervorgehenden Verfahrensschritte gelöst.According to the invention, this object is achieved by the method steps resulting from the characterizing part of
Vorteilhafterweise wird für die Bewegung des Ausgangsmaterials eines speziellen Werkstücks und / oder deren zeitliche Ableitungen ein Toleranzband für die charakteristischen Werte von Gutteil- und Schlechteil- Umformabläufen aus Kalibrierumformprozessen ermittelt und aus dem Toleranzband eine Führungsgröße für die Bewegung des Ausgansmaterials und / oder deren zeitliche Ableitungen abgeleitet.It is advantageous for the movement of the starting material of a special workpiece and / or its time derivatives, a tolerance band for the characteristic values of good part and bad part forming processes is determined from calibration forming processes and a reference variable for the movement of the starting material and / or its time derivatives is derived from the tolerance band.
Weitere prozeßrelevante Signale können als zusätzliche Führungsgrößen eingesetzt werden, wobei bei der Regelung des Umformprozesses die Signifikanz dieser Signale gegenüber der Bewegung des Ausgansmaterials und / oder deren zeitliche Ableitungen aus Kalibriermessungen bestimmt wird. Für die Größe des Werkzeugspaltes kann ein weiteres prozeßrelevantes Signal als zusätzliche Führungsgröße eingesetzt werden. Für die Kennwerte aus der Körperschallanalyse an der Formteilform können weitere prozeßrelevante Signale als die zusätzlichen Führungsgrößen eingesetzt werden.Further process-relevant signals can be used as additional reference variables, the significance of these signals in relation to the movement of the starting material and / or their time derivatives being determined from calibration measurements when regulating the forming process. Another process-relevant signal can be used as an additional command variable for the size of the tool gap. For the characteristic values from the structure-borne noise analysis on the molded part, further process-relevant signals can be used as the additional reference variables.
Das erfindungsgemäße Verfahren gerwährleistet aus verhältnismäßig einfache und effektive Weise eine praktisch fehlerfreie Herstellung von Preßteilen im Preßwerk durch Regelung des Umformprozesses derart, daß das Einzieher des Blechs in die Ziehform in einem Wirkzusammenhang mit der Bewegung des Ziehstempels erfolgt. Die Bewegung des Blechs am Niederhalter wird gemessen und über die Stellgröße "Niederhalterkraft" so geregelt, daß sie der Bewegung des Blechs für einen Gutteil-Umformvorgang entspricht. Das Toleranzband für eine für eine werkstückspezifische Niederhalterkraft wird über Kalibriermessungen ermittelt, die die charakteristischen Werte von Gutteil- und Schlechtteil- Umformprozeßabläufen umfassen.The method according to the invention ensures, from a relatively simple and effective manner, a practically flawless production of pressed parts in the pressing plant by regulating the forming process in such a way that the sheet is drawn into the drawing mold in an operative connection with the movement of the drawing die. The movement of the sheet on the hold-down device is measured and regulated via the manipulated variable "hold-down force" so that it corresponds to the movement of the sheet for a good part forming process. The tolerance band for a workpiece-specific hold-down force is determined using calibration measurements, which include the characteristic values of good part and bad part forming processes.
Das erfindungsgemäße Verfahren wird und anhand der Zeichnungen erläutert. In diesen sind:
- Fig. 1
- ein Diagramm, das den Verlauf der Blechhalterkraft über einen Ziehvorgang für die Fälle der Faltenbildung, Gutteil, Reißer bei einer prozeßgesteuerten Preßteilfertigung zeigt,
- Fig. 2
- eine Meßanordnung zur direkten optischen Messung der Blechposition beim Umformprozeß,
- Fig. 3
- eine Anordnung zur induktiven Messung der Blechgeschwindigkeit, wobei a) einen Querschnitt durch die Presse und b) eine Aufsicht auf den Niederhalter zeigt, und
- Fig. 4
- eine Anordnung zur Messung der Blechgeschwindigkeit beim Umformprozeß mit Korrelationsverfahren.
- Fig. 1
- 1 shows a diagram which shows the course of the sheet metal holder force over a drawing process for the cases of wrinkling, good part, tear in a process-controlled pressed part production,
- Fig. 2
- a measuring arrangement for the direct optical measurement of the sheet metal position during the forming process,
- Fig. 3
- an arrangement for inductive measurement of the sheet metal speed, wherein a) shows a cross section through the press and b) a top view of the hold-down device, and
- Fig. 4
- an arrangement for measuring the sheet metal speed in the forming process with correlation methods.
Fig. 1 zeigt den Verlauf der Blechhalterkraft während des Umformvorgangs für Schlechtteil- Umformabläufe (Faltenbildung bzw. Reißer) und einen Gutteil-Umformablauf. Bei der Herstellung der Formteile mittels des durch Kraft- oder Druckeinwirkung beeinflußten Umformprozesses wird für die Bewegung des Ausgangsmaterials des Werkstücks gemäß Fig. 1 ein Toleranzband für die charakteristischen Werte der Gutteil- und Schlechtteil - Umformabläufe aus Kalibrierumformprozessen ermittelt. Aus dem Toleranzband wird dann eine Führungsgröße für die Bewegung des Ausgangsmaterials abgeleitet.Fig. 1 shows the course of the sheet metal holder force during the forming process for bad part forming processes (wrinkling or tearing) and a good part forming process. In the production of the molded parts by means of the forming process influenced by the action of force or
Zur Bestimmung der Materialgeschwindigkeit beim Umformprozeß. z.B. beim Tiefziehprozeß kann die Bewegung des Werkstoffs entweder direkt gemessen oder über Korrelationsmessungen der Materialtextur an verschiedenen Punkten die Materialgeschwindigkeit festgestellt werden. So geht aus Fig. 2 eine Meßanordnung zur direkten Messung der Blechposition hervor, bei der um das Werkstück 1, das auf einem Niederhalter 2 aufliegend zwischen einem Ziehkissen 3 und einem Stempel 4 einer Presse angeordnet ist, eine Reihe von optischen Triangulationssensoren 5 angeordnet ist, mit denen gezielt die Wanderung einzelner Punkte des Randes des Werkstücks 1 beobachtet wird. Für jeden dieser Punkte wird ein Weg - Zeit - Diagramm erstellt. Durch Vergleich der Kurvenverläufe mit den korrespondierenden Daten des IO-Prozesses ist dann eine Online - Regelung des Umformvorgangs möglich.To determine the material speed during the forming process. e.g. In the deep-drawing process, the movement of the material can either be measured directly or the material speed can be determined at various points via correlation measurements of the material texture. 2 shows a measuring arrangement for direct measurement of the sheet metal position, in which a series of
Fig. 3 zeigt eine Anordnung zur induktiven Messung der Blechgeschwindigkeit, mit der die Induktion von Spannungen bei der Bewegung eines Leiters in einem Magnetfeld ausgenutzt wird. Fig. 3a und 3b zeigen einen Querschnitt durch die Presse bzw. eine Aufsicht auf den Niederhalter 2. Im Niederhalter 2 und / oder im Ziehkissen ist jeweils eine Spule 6 eingelassen, die an eine Gleichspannungsquelle 7 angeschlossen ist. Weiterhin sind zwei Kontaktstifte 8 in dem Niederhalter 2 (Fig. 3b) oder in dem Ziekissen 3 eingebaut, zwischen denen die durch die Bewegung induzierte Spannung abgegriffen wird. Die Anordnung der beiden Kontaktstifte 8 muß aufgrund der Lentz'schen Regel so sein, daß die Verbindungslinie zwischen den beiden Kontaktstiften 8 sowohl senkrecht zum Magnetfeld als auch zur Bewegungsrichtung A (siehe Pfeil in Fig. 3b) des Materials angeordnet ist.3 shows an arrangement for the inductive measurement of the sheet metal speed, with which the induction of voltages during the movement of a conductor in a magnetic field is used. 3a and 3b show a cross section through the press or a view of the hold-
Die Ermittlung der Bewegung des Werkstoffs kann beim Umformprozeß auch auf indirekte Weise ermittelt werden, z.B. durch Messung der Blechgeschwindigkeit mit Korrelationsverfahren, wie aus Fig. 4 hervorgeht. Hierbei wird die Materialtextur an diversen Punkten der Platine 1 mittels der im Niederhalter 2 angeordneten Sensoren 5 vermessen, deren Signale jeweils auf einem Bildschirm 9 dargestellt werden. Aus den entsprechenden Ausgangssignalen 10 wird mittels eines Korrelators 11 die Kreuzkorrelationsfunktion (KKF) jeweils zwischen den beiden Signalen berechnet und auf einem Bildschirm 12 dargestellt. Aus der Lage der Hauptmaxima der Kreuzkorrelationsfunktionen kann die Laufzeit des Materials und somit die Geschwindigkeit des Materials als Quotient von Sensorabstand b und Laufzeit berechnet werden.The determination of the movement of the material can also be determined indirectly in the forming process, e.g. by measuring the sheet speed with correlation methods, as can be seen in FIG. 4. Here, the material texture is measured at various points on the
Die Materialtextur kann mittels interferometrischer Verfahren, mittels mechanisch - induktiver Verfahren oder mittels berührungsloser induktiver Wegaufnehmer gemessen werden. Zur interferometrischen Texturmessung können sog. Heterodyn - Profiler eingesetzt werden, die nicht übermäßig vibrationsempfindlich sind und von denen die Materialoberfläche durch zwei kolliniare Laserstrahlen mit geringfügig unterschiedlicher Frequenz beleuchtet wird. Werden diese beiden Laserstrahlen nach Reflexion an der Materialoberfläche zur Interferenz gebracht, so ergibt sich eine Phasendifferenz, die direkt vom Höhenunterschied der beiden Lichtfleckorte auf der Materialoberfläche abhängig ist.The material texture can be measured by means of interferometric methods, by means of mechanical-inductive methods or by means of non-contact inductive displacement sensors. So-called heterodyne profilers can be used for interferometric texture measurement, which are not excessively sensitive to vibration and of which the material surface is slightly affected by two collinear laser beams different frequency is illuminated. If these two laser beams are brought to interference after reflection on the material surface, a phase difference results which is directly dependent on the difference in height of the two light spot locations on the material surface.
Zur mechanisch-induktiven Texturmessung werden in dem Niederhalter und in dem Ziehkissen induktive Wegaufnehmer mit Tastspitzen eingebaut. Mit derart herkömmlichen Sensoren, deren Auflösung im Submikrobereich liegt,kann die Rauigkeit des Materials geeignet abgetatstet werden, die im Bereich von Mikrometern liegt. Werden drei Sensoren auf den Eckpunkten eines rechtwinkligen Dreiecks angeordnet, so kann die Geschwindigkeit vektoriell erfaßt werden.For mechanical-inductive texture measurement, inductive displacement sensors with probe tips are installed in the holding-down device and in the die cushion. With such conventional sensors, the resolution of which is in the submicro range, the roughness of the material, which is in the range of micrometers, can be suitably scanned. If three sensors are arranged on the corner points of a right-angled triangle, the speed can be recorded vectorially.
Sensoren zur berührungslosen induktiven Wegaufnahme weisen für gewöhnlich eine verhältnismäßig große Querschnittsfläche auf, wobei der Durchmesser im Millimeterbereich liegt. Das Meßsignal ist aber gleichsam ein Integral über diese Querschnittsfläche. Da die Rauigkeit des Materials sich jedoch über erheblich kürzere Entfernungen ändert, können nur Sensoren eingesetzt werden, deren Tastfläche entsprechend verkleinert worden ist,und zwar z.B. durch Umbau der Spulenkerne.Sensors for contactless inductive displacement measurement usually have a relatively large cross-sectional area, the diameter being in the millimeter range. The measurement signal is, however, an integral over this cross-sectional area. However, since the roughness of the material changes over considerably shorter distances, only sensors can be used whose tactile area has been reduced accordingly, e.g. by converting the coil cores.
Claims (5)
- Method for making products (1) by force or pressure influenced drawing processes, especially of deep drawing sheet steel (1) for body parts of motor vehicles, by control of the drawing process, whereby the movement of the basic material (1) for the drawing process is measured in its course and set by the applied force or the applied pressure in such a manner that the movement of the product (1) equals the movement of the product, independent of affecting disturbances, at a good part - drawing process, characterized thereby, that in addition the time deviations of the movement of the basic material are measured at the drawing process and are set by the applied force or the applied pressure in such a manner, that in addition the deviations in time of the movement of the product (1) equal, independent of affecting disturbances, the movement of the product (1) and its deviations in time at a good part - drawing process and that the measurement of the movement of the basic material and its deviations in time takes place by the sensory registration of the material texture through computing the speed of the basic material (1) via the cross correlation function between two signals of two sensors (5) intended in a short distance at the basic material (1).
- Procedure according to claim 1, characterized thereby, that for the movement of the basic material (1) of a work piece (2) and its deviations in time a tolerance band is determined for the characteristic values of good part- and bad part - drawing courses from calibration drawing processes and a command variable is derived for the movement of the basic material and its deviations in time from the tolerance band.
- Procedure according to claim 1 to 2 characterized thereby , that further process-relevant signals are used as additional command variables, whereby at the control of the drawing process the significance of these signals compared with the movement of the basic material (1) and its deviations in time is determined from calibration measurements.
- Procedure according to claim 3, characterized thereby, that a further process-relevant signal is used as additional command variable for the size of the tool gap.
- Procedure according to claim 3 and 4, characterized thereby, that for the characteristic values from the structure-borne noise analysis at the product mould further process-relevant signals are used as additional command variables.
Priority Applications (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| DE59208404T DE59208404D1 (en) | 1992-07-18 | 1992-07-18 | Process for the production of molded parts by means of forming processes influenced by the action of force or pressure |
| EP19920112315 EP0589066B1 (en) | 1992-07-18 | 1992-07-18 | Method for making products by force or pressure influenced drawing processes |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| EP19920112315 EP0589066B1 (en) | 1992-07-18 | 1992-07-18 | Method for making products by force or pressure influenced drawing processes |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| EP0589066A1 EP0589066A1 (en) | 1994-03-30 |
| EP0589066B1 true EP0589066B1 (en) | 1997-04-23 |
Family
ID=8209821
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| EP19920112315 Expired - Lifetime EP0589066B1 (en) | 1992-07-18 | 1992-07-18 | Method for making products by force or pressure influenced drawing processes |
Country Status (2)
| Country | Link |
|---|---|
| EP (1) | EP0589066B1 (en) |
| DE (1) | DE59208404D1 (en) |
Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE102004031222B3 (en) * | 2004-06-28 | 2005-08-11 | Benteler Automobiltechnik Gmbh | Metal plate structural component for a motor vehicle with a design fracture point between at least two plates has a load detector and film sensor connected to an evaluation unit to permit early diagnosis of joint failure |
| DE102004031184B3 (en) * | 2004-06-28 | 2005-10-06 | Benteler Automobiltechnik Gmbh | Motor vehicle`s body component, has detector unit including voltage source and voltmeter for measuring electrical signal, and detecting change of state of measured electrical signal to identify fissure in structural component |
| WO2008020099A1 (en) | 2006-08-08 | 2008-02-21 | Ricardo Arenzana Zorrilla | Shaping tool with sensitive unit |
| DE202017103894U1 (en) | 2017-06-29 | 2018-10-16 | Forschungsgesellschaft Umformtechnik Mbh | Device for regulating the deep-drawing process during the press stroke |
| DE102017114596A1 (en) | 2017-06-29 | 2019-01-03 | Forschungsgesellschaft Umformtechnik Mbh | Method and device for regulating the deep-drawing process during the press stroke |
| DE102019205464B3 (en) * | 2019-04-16 | 2020-09-24 | Volkswagen Aktiengesellschaft | Method for determining the sheet infeed in a sheet metal forming tool, as well as press-bound deep-drawing tool and method for regulating a deep-drawing process |
Families Citing this family (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2002090875A2 (en) * | 2001-05-07 | 2002-11-14 | Northwestern University | Real-time draw-in sensors and methods of fabrication |
| DE10208377A1 (en) * | 2002-02-27 | 2003-09-25 | Fraunhofer Ges Forschung | Device for contactless distance measurement to a surface located in a narrow gap |
| DE102010011849A1 (en) | 2009-09-30 | 2011-04-07 | Micro-Epsilon Messtechnik Gmbh & Co. Kg | Thin body i.e. ferromagnetic plate, position and/or movement determining device for body parts of motor vehicle, has evaluation device determining movement and/or position of body from detected magnetic field distribution change |
| DE202010013721U1 (en) | 2009-09-30 | 2011-04-28 | Micro-Epsilon Messtechnik Gmbh & Co. Kg | Device for detecting the movement of a thin body |
-
1992
- 1992-07-18 EP EP19920112315 patent/EP0589066B1/en not_active Expired - Lifetime
- 1992-07-18 DE DE59208404T patent/DE59208404D1/en not_active Expired - Fee Related
Cited By (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE102004031222B3 (en) * | 2004-06-28 | 2005-08-11 | Benteler Automobiltechnik Gmbh | Metal plate structural component for a motor vehicle with a design fracture point between at least two plates has a load detector and film sensor connected to an evaluation unit to permit early diagnosis of joint failure |
| DE102004031184B3 (en) * | 2004-06-28 | 2005-10-06 | Benteler Automobiltechnik Gmbh | Motor vehicle`s body component, has detector unit including voltage source and voltmeter for measuring electrical signal, and detecting change of state of measured electrical signal to identify fissure in structural component |
| WO2008020099A1 (en) | 2006-08-08 | 2008-02-21 | Ricardo Arenzana Zorrilla | Shaping tool with sensitive unit |
| DE202017103894U1 (en) | 2017-06-29 | 2018-10-16 | Forschungsgesellschaft Umformtechnik Mbh | Device for regulating the deep-drawing process during the press stroke |
| DE102017114596A1 (en) | 2017-06-29 | 2019-01-03 | Forschungsgesellschaft Umformtechnik Mbh | Method and device for regulating the deep-drawing process during the press stroke |
| DE102017114596B4 (en) * | 2017-06-29 | 2020-10-01 | Forschungsgesellschaft Umformtechnik Mbh | Method and device for regulating the deep-drawing process of a blank during a press stroke |
| DE102019205464B3 (en) * | 2019-04-16 | 2020-09-24 | Volkswagen Aktiengesellschaft | Method for determining the sheet infeed in a sheet metal forming tool, as well as press-bound deep-drawing tool and method for regulating a deep-drawing process |
Also Published As
| Publication number | Publication date |
|---|---|
| EP0589066A1 (en) | 1994-03-30 |
| DE59208404D1 (en) | 1997-05-28 |
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