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EP0003476B1 - Bending tool for producing u-shaped blanks - Google Patents

Bending tool for producing u-shaped blanks Download PDF

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Publication number
EP0003476B1
EP0003476B1 EP78101706A EP78101706A EP0003476B1 EP 0003476 B1 EP0003476 B1 EP 0003476B1 EP 78101706 A EP78101706 A EP 78101706A EP 78101706 A EP78101706 A EP 78101706A EP 0003476 B1 EP0003476 B1 EP 0003476B1
Authority
EP
European Patent Office
Prior art keywords
bending
jaws
tool
punch
additional
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired
Application number
EP78101706A
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German (de)
French (fr)
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EP0003476A1 (en
Inventor
Dietrich Kreuzgruber
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Voestalpine AG
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Voestalpine AG
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Filing date
Publication date
Application filed by Voestalpine AG filed Critical Voestalpine AG
Publication of EP0003476A1 publication Critical patent/EP0003476A1/en
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Publication of EP0003476B1 publication Critical patent/EP0003476B1/en
Expired legal-status Critical Current

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    • BPERFORMING OPERATIONS; TRANSPORTING
    • B21MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21DWORKING OR PROCESSING OF SHEET METAL OR METAL TUBES, RODS OR PROFILES WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21D5/00Bending sheet metal along straight lines, e.g. to form simple curves
    • B21D5/02Bending sheet metal along straight lines, e.g. to form simple curves on press brakes without making use of clamping means
    • B21D5/0209Tools therefor

Definitions

  • the invention relates to a bending tool for producing U-shaped workpieces with a bending stamp, preferably placed on its flanks, which dips between two bending jaws while taking along a flat support of the workpiece on the bending die.
  • the elastic springback of the bent legs must be taken into account after the load has been relieved by the bending tool. For this reason, the leg of the U-profile should be bent beyond the desired bending angle by the amount of elastic resilience so that after the leg has rebounded, the leg can actually assume the desired position. Since the elastic springback of the leg depends on the one hand on the material properties and on the other hand on the thickness of the workpiece, the known bending tools (e.g. according to DE-A 2003614), which only allow a certain bending angle, are only suitable for certain workpieces, so that for example workpieces with more different thicknesses can no longer be processed with the same bending tool.
  • the constructive measure taken on a tool to compensate for the elastic springback of the legs can therefore only be successful because of the unchangeable end face curvature for workpieces that do not differ significantly from one another in terms of their thickness.
  • the bending angle given by pressing on the punch naturally results in the bending of the leg required to achieve a specific bending angle only for a workpiece made of a specific material and a specific thickness.
  • the invention has for its object to improve a bending tool of the type described in such a way that it can be used universally without special retrofitting that workpieces of various thicknesses are machined in compliance with the required tolerances and preferably also different bending angles exceeding 90 ° are set can.
  • the invention solves the problem in that the bending jaws, viewed in the direction of the working stroke of the bending punch, are followed by two additional jaws, which are supported on slidingly converging, stationary wedge surfaces converging in the working stroke direction of the bending punch, and in that the counterhold takes effect after a certain stroke for carrying along the wedge surfaces of the additional jaws held in an initial position adjacent to the bending jaws at the beginning of the working stroke.
  • the provision of two additional jaws, which are supported slidably on wedge surfaces makes it possible to additionally bend the legs of the workpiece bent between the actual bending jaws in order to take the spring-back angle into account. Since the additional jaws are only taken along after a certain stroke of the counter-holder or the bending die, the actual bending process is in no way impaired by the additional jaws.
  • the additional jaws with them Only by taking the additional jaws with them do they rest on the outside of the bent legs due to their wedge guidance and press them against each other, the dimension of this additional bending angle depending on the immersion depth of the bending die between the bending jaws.
  • the wedge surfaces provided for guiding the additional jaws converge in the working stroke direction of the bending die.
  • the bending angle can also be determined via the stroke of the bending die, so that workpieces of the most varied materials and thicknesses can be processed with the aid of the bending tool according to the invention.
  • the different elastic resilience for each of these workpieces, each of which requires its own bending angle can thus be taken into account by means of the stroke of the bending die, without a special retooling of the bending tool being required within certain limits.
  • one of one can be bent on the bending punch Leg of the workpiece actuated stroke limit switch can be provided, which automatically ends the working stroke of the punch when the bent leg has reached the desired bending angle.
  • By adjusting the stroke limit switch away from the leg and towards the leg all desired bending angles can be achieved exactly. A prerequisite for this is, of course, that the bending punch gives space for an additional free bending of the legs.
  • the spatial distance between the wedge surfaces from one another can be adjusted with the aid of adjusting wedges distributed over the tool length.
  • each of the two wedge surfaces for supporting the additional jaws in the central region of the tool can thus be pressed against the punch, so that despite the deflection, the same conditions result for the additional bending of the legs over the entire length of the tool.
  • the respective spacing of the two wedge surfaces from one another in the region of the additional jaws can thus be kept constant over the tool length, despite different immersion depths.
  • the illustrated bending tool for producing U-shaped workpieces essentially consists of a bending punch 1, a counter-holder 2 which interacts with the bending punch 1 and two bending jaws 3 which are shown in FIG. a machine tool base 4 are provided.
  • the bending tool shown also has two additional jaws 5, which are arranged downstream of the bending jaws 3 with respect to the working stroke direction of the punch 1 and are each supported on a wedge surface 6, the two wedge surfaces 6 converging in the direction of the working stroke of the bending punch 1.
  • the counter-holder 2 which presses the workpiece against the end face of the bending die during the bending process and is displaced by the bending die against the pressing force, has drivers 7, which interact with driver stops 8 of the additional jaws 5 and take the additional jaws 5 after a certain stroke distance, as is the case with 2 to 4 can be clearly seen. Due to the slidable support of the additional jaws 5 on the wedge surfaces 6, the additional jaws 5 are additionally pressed in by the entrainment of the counter-holder 2, so that they can act on the already bent legs 9 of the workpiece 10 bent in a U-shape between the actual bending jaws 3 and Bend them inwards depending on the immersion depth of the punch 1.
  • a stroke limiting switch 12 is provided on the punch 1, which is actuated by the corresponding leg 9 when the switch 12 set angle is reached.
  • adjusting wedges 13 are provided which are distributed over the tool length and can be actuated by means of adjusting screws 14. By adjusting the setting wedges 13 accordingly, the wedge surfaces 6 can be arched in order to adapt the local distance between the two wedge surfaces 6 to the different immersion depth of the plunger 1, so that the influence of the deflection can be completely eliminated by this adaptation.

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  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Bending Of Plates, Rods, And Pipes (AREA)
  • Formation And Processing Of Food Products (AREA)

Description

Die Erfindung bezieht sich auf ein Abbiegewerkzeug zum Herstellen U-förmiger Werkstücke mit einem vorzugsweise an seinen Flanken hintersetzten Biegestemple, der unter Mitnahme eines die flächige Anlage des Werkstückes am Biegestempel sicherstellenden Gegenhalters zwischen zwei Biegebacken eintaucht.The invention relates to a bending tool for producing U-shaped workpieces with a bending stamp, preferably placed on its flanks, which dips between two bending jaws while taking along a flat support of the workpiece on the bending die.

Um beim Abbiegen von Werkstücken zu U-Profilen od. dgl. genaue Biegewinkel erreichen zu können, muß die elastische Rückfederung der abgebogenen Schenkel nach der Entlastung durch das Abbiegewerkzeug berücksichtigt werden. Aus diesem Grund sollte der Schenkel des U-Profils über den gewünschten Biegewinkel hinaus um das Maß der elastischen Rückfederung abgebogen werden damit nach der Rückfederung des Schenkels dieser die gewünschte Lage auch tatsächlich einnehmen kann. Da die elastische Rückfederung des Schenkels aber einerseits von den Materialeigenschaften und anderseits von der Dicke des Werkstückes abhängt, sind die bekannten Abbiegewerkzeuge (z.B. gemäß DE-A 2003614), die nur einen bestimmten Biegewinkel ermöglichen, ausschließlich für bestimmte Werkstücke geeignet, so daß beispielsweise Werkstücke mit stärker unterschiedlichen Dicken nicht mehr mit demselben Abbiegewerkzeug bearbeitet werden können. Die an einem Werkzeug vorgenommene konstruktive Maßnahme, die elastische Rückfederung der Schenkel beispielsweise durch eine konkav geschliffene Stirnfläche des Biegestempels auszugleichen, kann daher wegen der unveränderbaren Stirnflächenwölbung nur für Werkstücke erfolgreich sein, die sich hinsichtlich ihrer Dicke nicht wesentlich voneinander unterscheiden. Gleiches gilt für Abbiegewerkzeuge, deren Biegebacken über einen Keiltrieb nach dem Biegevorgang einwärts gegen den Biegestempel gedrückt werden können, wobei der aufgebogene Schenkel des U-Profils an den Stempel angedrückt wird. Der durch das Andrücken an den Stempel gegebene Biegewinkel ergibt selbstverständlich nur für ein Werkstück aus einem bestimmten Werkstoff und einer bestimmten Dicke die zur Erreichung eines bestimmten Biegewinkels erforderliche Überbiegung des Schenkels. Abgesehen da von ist für die Biegebacken bei diesem bekannten Abbiegewerkzeug ein gesonderter Antrieb erforderlich, wobei die besondere Schwierigkeit auftritt, daß die beim eigentlichen Biegevorgang möglichst starren Biegebacken bewegt werden sollen. Durch das nachträgliche Andrücken der aufgebogenen Schenkel des U-Profils an die entsprechend geneigten Seiten des Biegestempels ist es jedoch möglich, bei entsprechender Ausbildung des Werkzeuges auch Profile herstellen zu können, deren Schenkel über 90° abgebogen sind, was bei den sonst üblichen Abbiegewerkzeugen nicht möglich ist.In order to be able to achieve precise bending angles when bending workpieces into U-profiles or the like, the elastic springback of the bent legs must be taken into account after the load has been relieved by the bending tool. For this reason, the leg of the U-profile should be bent beyond the desired bending angle by the amount of elastic resilience so that after the leg has rebounded, the leg can actually assume the desired position. Since the elastic springback of the leg depends on the one hand on the material properties and on the other hand on the thickness of the workpiece, the known bending tools (e.g. according to DE-A 2003614), which only allow a certain bending angle, are only suitable for certain workpieces, so that for example workpieces with more different thicknesses can no longer be processed with the same bending tool. The constructive measure taken on a tool to compensate for the elastic springback of the legs, for example by means of a concavely ground end face of the bending die, can therefore only be successful because of the unchangeable end face curvature for workpieces that do not differ significantly from one another in terms of their thickness. The same applies to bending tools, the bending jaws of which can be pressed inwards against the bending punch by means of a wedge drive after the bending process, the bent leg of the U-profile being pressed against the punch. The bending angle given by pressing on the punch naturally results in the bending of the leg required to achieve a specific bending angle only for a workpiece made of a specific material and a specific thickness. Apart from that, a separate drive is required for the bending jaws in this known bending tool, with the particular difficulty that the bending jaws that are as rigid as possible during the actual bending process should be moved. By subsequently pressing the bent legs of the U-profile onto the correspondingly inclined sides of the bending die, it is possible, with the appropriate design of the tool, to be able to also produce profiles whose legs are bent over 90 °, which is not possible with the usual bending tools is.

Der Erfindung liegt die Aufgabe zugrunde, ein Abbiegewerkzeug der eingangs geschilderten Art so zu verbessern, daß es ohne besondere Umrüstung derart universell eingesetzt werden kann, daß Werkstücke unterschiedlichster Dickenabmessungen unter Einhaltung der geforderten Toleranzen bearbeitet und vorzugsweise auch unterschiedliche, über 90° hinausgehende Biegewinkel eingestellt werden können.The invention has for its object to improve a bending tool of the type described in such a way that it can be used universally without special retrofitting that workpieces of various thicknesses are machined in compliance with the required tolerances and preferably also different bending angles exceeding 90 ° are set can.

Die Erfindung löst die gestellte Aufgabe dadurch daß den Biegebacken, in Richtung des Arbeitshubes des Biegestempels gesehen, zwei Zusatzbacken nachgeordnet sind, die sich an in Arbeitshubrichtung des Biegestempels konvergierenden, ortsfesten Keilflächen gleitfähig abstützen, und daß der Gegenhalter nach einem bestimmten Hubweg zu Wirkung kommende Mitnehmer für die Mitnahme der zu Beginn des Arbeitshubes in einer den Biegebacken benachbarten Anfangsstellung gehaltenen Zusatzbacken längs der Keilflächen aufweist. Durch das Vorsehen von zwei Zusatzbacken, die sich gleitfähig an Keilflächen abstützen, wird es möglich, die in üblicher Weise zwischen den eigentlichen Biegebacken abgebogenen Schenkel des Werkstückes zusätzlich abzubiegen, um den Rückfederwinkel zu berücksichtigen. Da die Zusatzbacken erst nach einem bestimmten Hubweg des Gegenhalters bzw. des Biegestempels mitgenommen werden, wird durch die Zusatzbacken der eigentliche Abbiegevorgang in keiner Weise beeinträchtigt.The invention solves the problem in that the bending jaws, viewed in the direction of the working stroke of the bending punch, are followed by two additional jaws, which are supported on slidingly converging, stationary wedge surfaces converging in the working stroke direction of the bending punch, and in that the counterhold takes effect after a certain stroke for carrying along the wedge surfaces of the additional jaws held in an initial position adjacent to the bending jaws at the beginning of the working stroke. The provision of two additional jaws, which are supported slidably on wedge surfaces, makes it possible to additionally bend the legs of the workpiece bent between the actual bending jaws in order to take the spring-back angle into account. Since the additional jaws are only taken along after a certain stroke of the counter-holder or the bending die, the actual bending process is in no way impaired by the additional jaws.

Erst durch die Mitnahme der Zusatzbacken legen sich diese auf Grund ihrer Keilführung an die Außenseite der abgebogenen Schenkel an und drücken diese gegeneinander, wobei das Maß dieses zusätzlichen Biegewinkels von der Eintauchtiefe des Biegestempels zwischen den Biegebacken abhängt. Die zur Führung der Zusatzbacken vorgesehenen Keilflächen konvergieren ja in Arbeitshubrichtung des Biegestempels. Uber den Hub des Biegestempels läßt sich somit neben der Berücksichtigung der Werkstückdicke auch der Überbiegewinkel bestimmen, so daß Werkstücke unterschiedlichster Werkstoffe und unterschiedlichster Dicke mit Hilfe des erfindungsgemäßen Abbiegewerkzeuges bearbeitet werden können. Die für jedes dieser Werkstücke unterschiedliche elastische Rückfederung, die jeweils einen eigenen Überbiegewinkel erfordert, läßt sich somit über den Hub des Biegestempels berücksichtigen, ohne daß innerhalb bestimmter Grenzen ein besonderes Umrüsten des Abbiegewerkzeuges erforderlich wäre.Only by taking the additional jaws with them do they rest on the outside of the bent legs due to their wedge guidance and press them against each other, the dimension of this additional bending angle depending on the immersion depth of the bending die between the bending jaws. The wedge surfaces provided for guiding the additional jaws converge in the working stroke direction of the bending die. In addition to taking the workpiece thickness into account, the bending angle can also be determined via the stroke of the bending die, so that workpieces of the most varied materials and thicknesses can be processed with the aid of the bending tool according to the invention. The different elastic resilience for each of these workpieces, each of which requires its own bending angle, can thus be taken into account by means of the stroke of the bending die, without a special retooling of the bending tool being required within certain limits.

Um mit einfachsten Mitteln den jeweils erforderlichen Abbiegewinkel festlegen zu können, kann in weiterer Ausbildung der Erfindung am Biegestempel ein von einem abgebogenen Schenkel des Werkstückes betätigbarer Hubbegrenzungsschalter vorgesehen sein, der den Arbeitshub des Biegestempels automatisch beendet, wenn der abgebogene Schenkel den gewünschten Biegewinkel erreicht hat. Durch eine Verstellung des Hubbegrenzungschalters vom Schenkel weg und zum Schenkel hin lassen sich somit alle gewünschten Biegewinkel exakt erreichen. Voraussetzung hiefür ist selbstverständlich, daß der Biegestempel Raum für ein zusätzliches freies Abbiegen der Schenkel gibt.In order to be able to determine the bending angle required in each case with the simplest of means, in a further embodiment of the invention, one of one can be bent on the bending punch Leg of the workpiece actuated stroke limit switch can be provided, which automatically ends the working stroke of the punch when the bent leg has reached the desired bending angle. By adjusting the stroke limit switch away from the leg and towards the leg, all desired bending angles can be achieved exactly. A prerequisite for this is, of course, that the bending punch gives space for an additional free bending of the legs.

Werden lange Werkstücke mit großer Kraft bearbeitet, so ergeben sich bezüglich der belasteten Werkzeugteile Durchbiegungen, was dazu führt, daß der Biegestempel in der Längsmitte des Werkzeuges weniger tief zwischen die Biegebacken eintaucht als in den Endbereichen. Auf Grund der Keilführung der Zusatzbacken bedeutet dies, daß im Mittelbereich des Werkzeuges der durch die Zusatzbacken erreichte zusätzliche Biegewinkel kleiner als der im Endbereich des Werkzeuges ist. Um diesen Fehler auszugleichen, ist gemäß einer weiteren Ausbildung der Erfindung der örtliche Abstand der Keilflächen voneinander mit Hilfe von über die Werkzeuglänge verteilt angeordneten Stellkeilen einstellbar. Über diese Keile kann somit jede der beiden Keilflächen für die Abstützung der Zusatzbacken im Mittelbereich des Werkzeuges gegen den Stempel hin vorgedrückt werden, so daß sich trotz der Durchbiegung gleiche Verhältnisse für die Zusatzbiegung der Schenkel über die gesamte Werkzeuglänge ergeben. Der jeweilige Abstand der beiden Keilflächen voneinander im Bereich der Zusatzbacken kann also trotz unterschiedlicher Eintauchtiefe über die Werkzeuglänge konstant gehalten werden.If long workpieces are machined with great force, there are deflections with regard to the loaded tool parts, which leads to the fact that the bending punch dips less deeply between the bending jaws in the longitudinal center of the tool than in the end regions. Because of the wedge guidance of the additional jaws, this means that in the central region of the tool the additional bending angle achieved by the additional jaws is smaller than that in the end region of the tool. In order to compensate for this error, according to a further embodiment of the invention, the spatial distance between the wedge surfaces from one another can be adjusted with the aid of adjusting wedges distributed over the tool length. Via these wedges, each of the two wedge surfaces for supporting the additional jaws in the central region of the tool can thus be pressed against the punch, so that despite the deflection, the same conditions result for the additional bending of the legs over the entire length of the tool. The respective spacing of the two wedge surfaces from one another in the region of the additional jaws can thus be kept constant over the tool length, despite different immersion depths.

In der Zeichnung ist der Erfindungsgegenstand in einem Ausführungsbeispiel schematisch dargestellt.In the drawing, the subject of the invention is shown schematically in one embodiment.

Es zeigen

  • Fig. 1 eine schaubildliche Darstellung eines erfindungsgemäßen Abbiegewerkzeuges und die
  • Fig. 2 bis 4 einen Querschnitt dieses Abbiegewerkzeuges in verschiedenen Arbeitsstellungen.
Show it
  • Fig. 1 is a perspective view of a bending tool according to the invention and the
  • Fig. 2 to 4 shows a cross section of this bending tool in different working positions.

Das dargestellte Abbiegewerkzeug zum Herstellen U-förmiger Werkstücke besteht im wesentlichen aus einem Biegestempel 1, einem mit dem Biegestempel 1 zusammenwirkenden Gegenhalter 2 und zwei Biegebacken 3, die in . einem Werkzeugmaschinenunterbau 4 vorge-' sehen sind. Über diesen üblichen Aufbau hinaus weist das dargestellte Abbiegewerkzeug noch zwei Zusatzbacken 5 auf, die den Biegebacken 3 bezüglich der Arbeitshubrichtung des Beigestempels 1 nachgeordnet sind und sich jeweils an einer Keilfläche 6 abstützen, wobei die beiden Keilflächen 6 in Richtung des Arbeitshubes des Biegestempels 1 konvergieren.The illustrated bending tool for producing U-shaped workpieces essentially consists of a bending punch 1, a counter-holder 2 which interacts with the bending punch 1 and two bending jaws 3 which are shown in FIG. a machine tool base 4 are provided. In addition to this usual construction, the bending tool shown also has two additional jaws 5, which are arranged downstream of the bending jaws 3 with respect to the working stroke direction of the punch 1 and are each supported on a wedge surface 6, the two wedge surfaces 6 converging in the direction of the working stroke of the bending punch 1.

Der Gegenhalter 2, der das Werkstück während des Abbiegevorganges gegen die Stirnseite des Biegestempels drückt und vom Biegestempel gegen die Andrückkraft verschoben wird, besitzt Mitnehmer 7, die mit Mitnehmeranschlägen 8 der Zusatzbacken 5 zusammenwirken und die Zusatzbacken 5 nach einem bestimmten Hubweg mitnehmen, wie dies die Fig. 2 bis 4 deutlich erkennen lassen. Auf Grund der gleitfähigen Abstützung der Zusatzbacken 5 an den Keilflächen 6 werden die Zusatzbacken 5 durch die Mitnahme vom Gegenhalter 2 zusätzlich einwärts gedrückt, so daß sie auf die bereits abgebogenen Schenkel 9 des zwischen den eigentlichen Biegebacken 3 U-förmig abgebogenen Werkstückes 10 einwirken können und diese in Abhängigkeit von der Eintauchtiefe des Stempels 1 zusätzlich einwärtsbiegen. Zur Rückstellung der Zusatzbacken 5 während des Leerhubes, der zugleich Ausstoßhub ist, sind Federn 11 vorgesehen. Über die Eintauchtiefe des Stempels 1 kann somit der Biegewinkel der Schenkel 9'in weiten Grenzen variiert werden. Die Berücksichtigung unterschiedlichster Rückfederungen der Schenkel 9 ist folglich möglich.The counter-holder 2, which presses the workpiece against the end face of the bending die during the bending process and is displaced by the bending die against the pressing force, has drivers 7, which interact with driver stops 8 of the additional jaws 5 and take the additional jaws 5 after a certain stroke distance, as is the case with 2 to 4 can be clearly seen. Due to the slidable support of the additional jaws 5 on the wedge surfaces 6, the additional jaws 5 are additionally pressed in by the entrainment of the counter-holder 2, so that they can act on the already bent legs 9 of the workpiece 10 bent in a U-shape between the actual bending jaws 3 and Bend them inwards depending on the immersion depth of the punch 1. Springs 11 are provided to reset the additional jaws 5 during the idle stroke, which is also the discharge stroke. The bending angle of the legs 9 ′ can thus be varied within wide limits via the immersion depth of the stamp 1. It is therefore possible to take into account the most varied springbacks of the legs 9.

Damit der gewünschte maximale Biegewinkel unmittelbar erfaßt werden kann und nicht über die Eintauchtiefe des Stempels 1 bestimmt werden muß, was zu Ungenauigkeiten führen kann, ist am Biegestempel 1 ein Hubbegrenzungsschalter 12 vorgesehen, der vom entsprechenden Schenkel 9 betätigt wird, wenn der über den Schalter 12 eingestellte Winkel erreicht ist. Durch ein Verstellen des Schalters 12 gegen den Schenkel 9 hin kann jeder beliebige Biegewinkel eingestellt werden, unabhängig vom Werkstück.So that the desired maximum bending angle can be detected directly and does not have to be determined via the immersion depth of the punch 1, which can lead to inaccuracies, a stroke limiting switch 12 is provided on the punch 1, which is actuated by the corresponding leg 9 when the switch 12 set angle is reached. By adjusting the switch 12 against the leg 9, any bending angle can be set, regardless of the workpiece.

Da sich auf Grund der Preßkräfte eine Durchbiegung des Werkzeuges insbesondere bei langen Abbiegewerkzeugen ergibt, besteht die Gefahr, daß über die Länge des Werkstückes ungleiche Abbiegewinkel für die Schenkel erreicht werden, weil sich zufolge der Werkzeugdurchbiegung in der Längsmitte des Werkzeuges eine geringere Eintauchtiefe des Stempels als in den Endbereichen ergibt. Um diese unterschiedlichen Eintauchtiefen ausgleichen zu können, muß der jeweilige Abstand der Zusatzbacken 5 über die Werkzeuglänge konstant gehalten werden. Dies wird dadurch erriecht, daß die geringere Eintauchtiefe des Stempels durch ein Gegeneinanderdrüken der Keilflächen 6 im Bereich der geringeren Eintauchtiefe ausgeglichen wird. Zu diesem Zweck sind über die Werkzeuglänge verteilt Stellkeile 13 vorgesehen, die mittels Stellschrauben 14 betätigt werden können. Durch entsprechende Einstellung der Stellkeile 13 können die Keilflächen 6 vorgewölbt werden, um den örtlichen Abstand der beiden Keilflächen 6 an die unterschiedliche Eintauchtiefe des Stempels 1 anzupassen, so daß durch diese Anpassung der Einfluß der Durchbiegung völlig ausgeschaltet werden kann.Since there is a deflection of the tool due to the pressing forces, particularly in the case of long bending tools, there is a risk that uneven bending angles will be achieved for the legs over the length of the workpiece, because the tool deflection in the longitudinal center of the tool means that the depth of the punch is less than in the end areas. In order to be able to compensate for these different immersion depths, the respective distance between the additional jaws 5 must be kept constant over the tool length. This is achieved by the fact that the lower immersion depth of the punch is compensated for by pressing the wedge surfaces 6 against one another in the region of the lower immersion depth. For this purpose, adjusting wedges 13 are provided which are distributed over the tool length and can be actuated by means of adjusting screws 14. By adjusting the setting wedges 13 accordingly, the wedge surfaces 6 can be arched in order to adapt the local distance between the two wedge surfaces 6 to the different immersion depth of the plunger 1, so that the influence of the deflection can be completely eliminated by this adaptation.

Claims (3)

1. A bending tool for manufacturing U-shaped workpieces, comprising a bending punch, which is preferably backed at its flanks and which is received between two bending jaws while driving a backing member, which ensures a surface contact between the workpiece and the bending punch, characterized in that the bending jaws (3) are succeeded in the direction of the working stroke of the bendina punch (1) by two additional jaws (5), which slidably bear on stationary wedge faces (6), which converge in the direction of the working stroke of the bending punch (1), and the backing member (2) comprises coupling elements (7) which serve to move the additional jaws (5) along the wedge faces, which additional jaws are held in an initial position near the bending jaws (3) at the beginning of the working stroke.
2. A bending tool according to claim 1, characterized in that the bending punch (1) is provided with a stroke-limiting switch (12), which is operable by a bent-off flange (9) of the workpiece (10).
3. A bending tool according to claim 1 or 2, characterized in that the distance between the wedges faces (6) is adjustable by means of adjusting wedges (13), which are distributed along the length of the tool and disposed between the base part (4) of the tool and that part of the tool which is provided with the associated wedge face (6).
EP78101706A 1978-02-06 1978-12-15 Bending tool for producing u-shaped blanks Expired EP0003476B1 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
AT781/78 1978-02-06
AT78178A AT353568B (en) 1978-02-06 1978-02-06 BENDING TOOL FOR MANUFACTURING U-SHAPED WORKPIECES

Publications (2)

Publication Number Publication Date
EP0003476A1 EP0003476A1 (en) 1979-08-22
EP0003476B1 true EP0003476B1 (en) 1980-09-17

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Application Number Title Priority Date Filing Date
EP78101706A Expired EP0003476B1 (en) 1978-02-06 1978-12-15 Bending tool for producing u-shaped blanks

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EP (1) EP0003476B1 (en)
AT (1) AT353568B (en)
DD (1) DD141467A5 (en)
DK (1) DK147754C (en)
FI (1) FI783866A (en)
IT (1) IT1166052B (en)
NO (1) NO143693C (en)

Families Citing this family (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4355619A (en) * 1980-10-01 1982-10-26 The Bendix Corporation Fast response two coil solenoid driver
NL8303472A (en) * 1983-10-10 1985-05-01 Liet Cornelis Hendricus DEVICE FOR BENDING SHEET MATERIAL.

Family Cites Families (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
AT137643B (en) * 1933-04-04 1934-05-25 Peter Binder Device for the production of connecting sleeves, in particular for the overlapping ends of box straps.
DE1652639B2 (en) * 1968-02-20 1972-05-10 Siemens AG, 1000 Berlin u. 8000 München BENDING PUNCH

Also Published As

Publication number Publication date
DK555878A (en) 1979-08-07
AT353568B (en) 1979-11-26
NO143693C (en) 1981-04-01
EP0003476A1 (en) 1979-08-22
NO143693B (en) 1980-12-22
DK147754C (en) 1985-05-20
ATA78178A (en) 1979-04-15
NO790048L (en) 1979-08-07
IT1166052B (en) 1987-04-29
FI783866A (en) 1979-08-07
DK147754B (en) 1984-12-03
DD141467A5 (en) 1980-05-07
IT7912419A0 (en) 1979-01-16

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