EP0590262B1 - Emboutissage profond hydromécanique assisté par explosion - Google Patents

Emboutissage profond hydromécanique assisté par explosion Download PDF

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Publication number
EP0590262B1
EP0590262B1 EP93111956A EP93111956A EP0590262B1 EP 0590262 B1 EP0590262 B1 EP 0590262B1 EP 93111956 A EP93111956 A EP 93111956A EP 93111956 A EP93111956 A EP 93111956A EP 0590262 B1 EP0590262 B1 EP 0590262B1
Authority
EP
European Patent Office
Prior art keywords
tool
shape
press
fluid
chamber
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 - Lifetime
Application number
EP93111956A
Other languages
German (de)
English (en)
Other versions
EP0590262A1 (fr
Inventor
Volker Dr. Thoms
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.)
Daimler Benz AG
Mercedes Benz AG
Original Assignee
Daimler Benz AG
Mercedes Benz AG
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by Daimler Benz AG, Mercedes Benz AG filed Critical Daimler Benz AG
Publication of EP0590262A1 publication Critical patent/EP0590262A1/fr
Application granted granted Critical
Publication of EP0590262B1 publication Critical patent/EP0590262B1/fr
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

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Classifications

    • 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
    • B21D22/00—Shaping without cutting, by stamping, spinning, or deep-drawing
    • B21D22/20—Deep-drawing
    • B21D22/205—Hydro-mechanical deep-drawing

Definitions

  • the invention is based on a method for hydromechanical deep-drawing of sheet metal into a shape specified by only one of the two tool parts, preferably the stamp, by means of a press, according to the preamble of the patent claim, as is known, for example, from DE-OS 37 09 181 .
  • hydromechanical deep drawing part of the drawing tool, preferably the die, is relatively simple and only needs to be adapted to the opposite tool part with respect to its contact surface, which considerably reduces tool costs.
  • very high pressures in the range from 600 to 1000 bar have to act in order to be able to press the sheet into the engraving of the punch true to shape. After these high pressures are effective over the entire surface of the workpiece, this results in very high forces that are considerably higher than the press loads that occur between the forming punch and the die in purely mechanical deep drawing, because there the load is essentially due to the material cross section in the drawing area and the yield stress of the material is determined.
  • Pressing times of two minutes can easily occur, which are much too long compared to the cycle times of four to six seconds that can be achieved with conventional body presses.
  • a disadvantage of the hydromechanical deep drawing of larger sheet metal parts in presses is that the presses are disproportionately expensive and still not rigid enough and that the process is not productive enough.
  • the object of the invention is to improve the generic method for hydromechanical deep-drawing of sheet metal by means of a press in such a way that the process is significantly increased in productivity and in this respect is approximated to purely mechanical deep-drawing and that the press is relieved of the high forces and is therefore much cheaper to manufacture with reasonable rigidity.
  • the method according to the invention not only represents a combination of the known hydromechanical deep drawing with the known explosion forming, whereby short cycle times and thus high productivity are achieved.
  • the inertial locking of the Stamp and the tool chamber by a correspondingly generous mass allocation, whereby the high, but only briefly acting forming forces are limited to these parts and are kept away from the press construction.
  • the press 1 shown is essentially formed with respect to its static part by a press frame 2 which contains lateral press stands, a press head at the top and a press foot at the bottom.
  • a press frame 2 which contains lateral press stands, a press head at the top and a press foot at the bottom.
  • a die 6 with a large mass is arranged on the press foot as the lower part of the tool. This mass assignment will be discussed in more detail below.
  • a die 7 which can be driven in a stroke direction 24 is required for shaping.
  • the shape with which the sheet 8 introduced into the press 1 is to be deep-drawn is predetermined by the stamp 7.
  • the die 6 arranged opposite the punch is designed in the form of an open tool chamber 9, which can be applied to the inserted sheet 8 in a liquid-tight and gas-tight manner with its upper end-face contact surface. Accordingly, seals are let into the contact surface of the die 6 that comes into contact with the sheet metal 8.
  • the sheet 8 inserted into the press is on its outer edge between this contact surface on the one hand and a correspondingly shaped counter-contact surface of a hold-down frame 5 on the front side of the hold-down bar 4, on the other hand, can be clamped.
  • the hold-down bear 4 is also covered with a very large mass, which will be discussed in more detail below.
  • the hold-down frame 5 is interchangeably screwed to the hold-down bear.
  • the hold-down bar with the hold-down frame is lowered onto the inserted sheet metal and pressed there in a liquid-tight manner and with sustained force.
  • the separately drivable plunger bear 3 is attached with the aforementioned stamp 7, which can be moved up and down within the hold-down bear 4 in the manner of the plunger of a double-acting deep-drawing press.
  • the holding-down frame 5 In order to be able to carry out a hydromechanical deep-drawing process with such a press, the holding-down frame 5 must be brought into sealing contact by lowering the holding-down bear 4 after inserting the sheet 8 into the press or onto the die 6.
  • the tool chamber 9, which is initially largely filled with liquid, must contain a certain residual volume of fuel or air.
  • a filling and emptying pump 19 which can be controlled by a control device 20 is connected to the tool chamber 9 via a filling and emptying line 25; the control unit for the pump 19 receives from the angle sensor 11 a timed trigger signal for the filling and emptying processes.
  • the valve 16 Before and during the descent of the plunger 7, an increasing pressure in the liquid and in the gas is generated in the tool chamber 9 in accordance with the plunger movement and the plunger force.
  • the valve 16 On the part of a control unit 18, which receives a timed trigger signal from an angle transmitter 11, the valve 16 is switched on at a suitable point in time during the pressing cycle for feeding a gaseous propellant charge into the tool chamber.
  • the possibility of feeding the propellant charge into the tool chamber 9 during the filling process is through a gas supply line opening into the tool chamber 17 with check valve 21 and created by the controllable gas supply valve 16.
  • the gaseous propellant charge can be supplied from the gas bottle 14 and - if and / or as far as necessary - from the oxygen bottle 15, in which the gases mentioned are stored in a high-tensioned form, so that they can be raised without pressure into the tool chamber, which is initially still under relatively low pressure 9 can be fed.
  • Both the liquid filling and the feeding of the gaseous propellant charge should be largely completed before the pusher bear 3 has approximately reached the reversal point of its stroke. It is thereby achieved that the tool chamber can be filled with gas or liquid at a relatively low pressure but at high speed. It may well be that during the filling, which of course takes place with increasing pressure, the sheet metal protrudes toward the descending stamp and - as far as the sheet metal touches the stamp - bulges into its engraving.
  • a control device 13 for the ignition device which also receives a timed ignition signal from the angle transmitter 11.
  • the ignition device 12 can be, for example, an electrical ignition device in the manner of a spark plug, as is known from the technology of internal combustion engines. A short current surge at high voltage can trigger a powerful spark at the electrodes of the spark plug, which ignites the propellant charge and causes an explosive build-up of pressure in the tool chamber, which is already under a relatively high pressure.
  • the pressure rises very quickly to a high peak value; this powerful pressure peak brings about the final shaping of the sheet in the engraving of the stamp.
  • the check valves 21 and 22 arranged in the gas supply line 17 and in the filling and emptying line 25 for the liquid, an outflow of the introduced media is prevented. Due to a vent hole 23 on the stamp, a resistance-free outflow of the air enclosed between the plate and the engraving of the stamp is ensured, so that the engraving can be formed cleanly and accurately through the plate.
  • a cooling of the burned propellants leads to a relatively rapid drop in pressure, which is, however, desirable in order to relieve the press construction from high forces.
  • the high pressure peaks of the exploding propellant charge and the resulting high forces exerted on the walls of the tool chamber 9 or the plunger 7 are kept away from the press construction or the press frame 2 by an inertial locking of these parts. This inertia locking is due to the generous mass allocation already mentioned above the die 6 or by a very large dimensioning of the ram bear 3 and the hold-down bear 4. Since the very high pressure peak is only effective for a very short time in the range of a few milliseconds, but which is sufficient to ensure that the sheet is completely formed, the masses involved cannot be moved out of the rest position.
  • the check valve 22 arranged in the filling and emptying line 25 for the liquid is designed to be controllable, so that the closing action can be canceled, if necessary, and emptying of the tool chamber 9 can be initiated if necessary.
  • the controllable check valve 22 receives a corresponding opening signal from the control device 20 for the pump, so that an outflow of a corresponding part of the enclosed liquid can be initiated at a suitable time within the pressing cycle, for example before the propellant charge is fed in. Not only is the pump 19 driven in the outflow direction, but the residual pressure of the propellant charge that is present inside the tool chamber 9 also acts.
  • the advantage of the invention is that the advantages of a simple tool for hydromechanical deep drawing are fully retained, but that the disadvantages of this method are avoided, that relatively short press cycle times in the range of a few seconds can be achieved and that the press construction is subject to the high pressure forces is relieved.
  • the introduction of the propellant charge by allowing a gas to flow in is simpler than other conceivable possibilities for this, for example the position-defined introduction of an explosive tablet with an integrated ignition device into the tool chamber or an adiabatic compression of air or oxygen enclosed in the tool chamber in the manner of a diesel engine and injection of the fuel Propellant charge only in the form of a atomized liquid fuel at the time of ignition, the ignition temperature of which is below the compression temperature of the compressed gas.
  • Hydrogen would be suitable as the gas for the gaseous propellant charge used according to the invention, especially since it does not form any harmful combustion gases and the combustion products are readily compatible with the hydraulic fluid essentially formed by water; the combustion gases themselves very quickly condense into water.

Landscapes

  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Shaping Metal By Deep-Drawing, Or The Like (AREA)
  • Casting Devices For Molds (AREA)
  • Press Drives And Press Lines (AREA)

Claims (1)

  1. Procédé d'emboutissage profond hydromécanique de tôle à une forme prédéterminée seulement par l'une des deux parties d'outil, de préférence le poinçon, au moyen d'une presse qui comprend la partie d'outil qui détermine la forme, de préférence le poinçon (7), et une chambre d'outil (9) ouverte vers la partie d'outil qui détermine la forme et à laquelle un liquide sous pression peut être appliqué, l'une des deux parties pouvant être entraînée pour effectuer un mouvement de levage,
       dans lequel la tôle (8) est serrée à son bord extérieur d'une façon étanche aux liquides et aux gaz et sous une force continue entre une surface d'appui formée sur le côté frontal de la partie d'outil qui détermine la forme, de préférence le poinçon (7) ou serre-flan, et une contre-surface d'appui de forme correspondante sur le côté frontal de la chambre (9) d'outil,
       dans lequel en outre une pression croissante est appliquée à la chambre (9) d'outil remplie de liquide, la tôle extensible (8) étant emboutie par la pression de liquide, tandis que le bord de tôle glisse hors du serrage de bord, et étant enfoncée dans la gravure de la partie d'outil qui détermine la forme en épousant exactement sa forme,
       caractérisé en ce que
       une charge active appropriée formée d'un gaz combustible mélangé à de l'oxygène est introduite dans la chambre (9) d'outil avant ou pendant le remplissage de la chambre (9) d'outil au moyen d'un liquide, la chambre (9) d'outil est remplie de liquide sous pression en continu sous une pression relativement faible et la charge active est allumée à un instant précis pour achever le processus d'emboutissage et en ce que la structure (2) de la presse est préservée des forces qui s'exercent brièvement dans la direction de déplacement (24) de la partie (7) d'outil mobile pour le levage sous l'effet de l'explosion de la charge active sur la partie d'outil qui détermine la forme, de préférence le poinçon (7), et sur la chambre (9) d'outil, en garnissant de masses de dimensions appropriées ces parties.
EP93111956A 1992-10-01 1993-07-27 Emboutissage profond hydromécanique assisté par explosion Expired - Lifetime EP0590262B1 (fr)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
DE4232913 1992-10-01
DE4232913A DE4232913C2 (de) 1992-10-01 1992-10-01 Zweistufiges Verfahren zum hydromechanischen explosionsunterstützen Tiefziehen von Blech und Tiefziehpresse zur Durchführung des Verfahrens

Publications (2)

Publication Number Publication Date
EP0590262A1 EP0590262A1 (fr) 1994-04-06
EP0590262B1 true EP0590262B1 (fr) 1996-04-17

Family

ID=6469316

Family Applications (1)

Application Number Title Priority Date Filing Date
EP93111956A Expired - Lifetime EP0590262B1 (fr) 1992-10-01 1993-07-27 Emboutissage profond hydromécanique assisté par explosion

Country Status (3)

Country Link
EP (1) EP0590262B1 (fr)
DE (2) DE4232913C2 (fr)
ES (1) ES2087621T3 (fr)

Cited By (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US8047036B2 (en) 2005-06-03 2011-11-01 Magna International Inc. Device and method for explosion forming
US8250892B2 (en) 2006-12-01 2012-08-28 Cosma Engineering Europe Ag Closure device for explosion forming
US8252210B2 (en) 2006-08-11 2012-08-28 Cosma Engineering Europe Ag Method and device for explosion forming
US8322175B2 (en) 2006-12-20 2012-12-04 Cosma Engineering Europe Ag Workpiece and method for explosion forming
US8650921B2 (en) 2006-08-11 2014-02-18 Cosma Engineering Europe Ag Method and device for explosion forming
US8713982B2 (en) 2008-01-31 2014-05-06 Magna International Inc. Device for explosive forming
US8875553B2 (en) 2007-02-14 2014-11-04 Cosma Engineering Europe Ag Method and mould arrangement for explosion forming
US8939743B2 (en) 2007-08-02 2015-01-27 Cosma Engineering Europe Ag Device for supplying a fluid for explosion forming
US9393606B2 (en) 2007-05-22 2016-07-19 Cosma Engineering Europe Ag Ignition device for explosive forming

Families Citing this family (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
ES2103656B1 (es) * 1994-10-06 1998-05-01 Idem Construcciones Vascas S L Sistema de embuticion por agua inyectada para la conformacion de piezas.
DE4436437C2 (de) * 1994-10-12 1996-09-05 Hde Metallwerk Gmbh Verfahren zum hydrostatischen Umformen von insbesondere ebenen Blechen aus kaltumformbarem Metall und diesbezügliche Vorrichtung zur Durchführung des Verfahrens
DE4436436C2 (de) * 1994-10-12 1996-08-22 Hde Metallwerk Gmbh Verfahren zum hydrostatischen Umformen von insbesondere ebenen Blechen aus kaltumformbarem Metall und Vorrichtung durch Durchführung des Verfahrens
DE19827614B4 (de) * 1998-06-20 2005-08-25 Steinhart, Paul, Dipl.-Ing. Verfahren und Vorrichtung zur Herstellung von Tiefziehteilen
DE19846100C2 (de) 1998-10-07 2000-08-03 Sms Demag Ag Gleichstromlichtbogenofen zur Herstellung von Stahl sowie Verfahren hierzu
DE19955748A1 (de) * 1999-11-19 2001-05-23 Mannesmann Rexroth Ag Steuerung für eine hydromechanische Tiefzieheinrichtung
US7093470B2 (en) * 2002-09-24 2006-08-22 The Boeing Company Methods of making integrally stiffened axial load carrying skin panels for primary aircraft structure and fuel tank structures
DE102004059445B3 (de) * 2004-12-09 2005-09-15 Konrad Schnupp Verfahren und Vorrichtung zur pneumomechanischen Außenhochdruckumformung eines Werkstücks
CN111842606B (zh) * 2020-07-31 2025-04-01 河南孟电集团兴迪锻压设备制造有限公司 大型充液冲击复合成形装置使用方法
CN117066341A (zh) * 2023-08-29 2023-11-17 上海汇众汽车制造有限公司 管状零件的成型装置及其成型方法

Family Cites Families (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE1777208A1 (de) * 1968-09-25 1971-04-01 Hertel Heinrich Prof Dr Ing Vorrichtung zur Hochleistungsumformung von Werkstuecken,insbesondere aus Blech,mit Hilfe von Schockwirkungsmitteln
US3742746A (en) * 1971-01-04 1973-07-03 Continental Can Co Electrohydraulic plus fuel detonation explosive forming
CS229960B1 (en) * 1981-06-15 1984-07-16 Vaclav Penaz Equipment for pressure mode control in pressure chamber for hydrodynamic drawing
DE3709181A1 (de) * 1987-03-20 1988-09-29 Asea Ab Verfahren zur herstellung von komplizierten blechteilen und werkzeug fuer die druckumformung solcher blechteile

Cited By (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US8047036B2 (en) 2005-06-03 2011-11-01 Magna International Inc. Device and method for explosion forming
US8252210B2 (en) 2006-08-11 2012-08-28 Cosma Engineering Europe Ag Method and device for explosion forming
US8650921B2 (en) 2006-08-11 2014-02-18 Cosma Engineering Europe Ag Method and device for explosion forming
US8250892B2 (en) 2006-12-01 2012-08-28 Cosma Engineering Europe Ag Closure device for explosion forming
US8322175B2 (en) 2006-12-20 2012-12-04 Cosma Engineering Europe Ag Workpiece and method for explosion forming
US8875553B2 (en) 2007-02-14 2014-11-04 Cosma Engineering Europe Ag Method and mould arrangement for explosion forming
US9393606B2 (en) 2007-05-22 2016-07-19 Cosma Engineering Europe Ag Ignition device for explosive forming
US8939743B2 (en) 2007-08-02 2015-01-27 Cosma Engineering Europe Ag Device for supplying a fluid for explosion forming
US8713982B2 (en) 2008-01-31 2014-05-06 Magna International Inc. Device for explosive forming

Also Published As

Publication number Publication date
EP0590262A1 (fr) 1994-04-06
ES2087621T3 (es) 1996-07-16
DE59302247D1 (de) 1996-05-23
DE4232913A1 (de) 1994-04-07
DE4232913C2 (de) 1995-04-27

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