EP0192115B1 - Drawing apparatus for presses - Google Patents

Drawing apparatus for presses Download PDF

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Publication number
EP0192115B1
EP0192115B1 EP86101399A EP86101399A EP0192115B1 EP 0192115 B1 EP0192115 B1 EP 0192115B1 EP 86101399 A EP86101399 A EP 86101399A EP 86101399 A EP86101399 A EP 86101399A EP 0192115 B1 EP0192115 B1 EP 0192115B1
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EP
European Patent Office
Prior art keywords
pressure
cylinders
auxiliary
regulating
drawing apparatus
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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
EP86101399A
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German (de)
French (fr)
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EP0192115A2 (en
EP0192115A3 (en
Inventor
Gerhard Roos
Hartmut Dexling
Wolfgang Michael
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L Schuler GmbH
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L Schuler GmbH
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Publication of EP0192115A2 publication Critical patent/EP0192115A2/en
Publication of EP0192115A3 publication Critical patent/EP0192115A3/en
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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
    • B21D24/14—Devices controlling or operating blank holders independently, or in conjunction with dies pneumatically or hydraulically
    • 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
    • B21D24/04—Blank holders; Mounting means therefor
    • B21D24/08—Pneumatically or hydraulically loaded blank holders

Definitions

  • the invention relates to a drawing device on presses according to the preamble of claim 1, such as. B. has become known from DE-C-32 02 134.
  • Drawers are used to generate the sheet metal holding force during sheet metal forming (drawing) and to generate the ejector movement (raising) of the shaped workpiece in presses and transfer presses.
  • Drawers have a pressure cheek, which is displaced by moving the press ram into bottom dead center - end area of the forming process - via pressure rods with the application of the sheet metal holding force and follows the movement of the ram into top dead center - the area away from the tool - taking the formed workpiece with it.
  • the force of the drawing device, while the pressure cheek follows the movement of the ram into the top dead center is approximately the same as the sheet metal holding force during workpiece forming.
  • the workpieces are pressed against the upper part of the tool when they are ejected via the push rods and can be deformed.
  • a drawing apparatus is used to avoid the deformation of the workpieces with a pressure cheek that follows the movement of the ram in its top dead center.
  • the press ram presses the pressure cheek into the bottom dead center as in the uncontrolled pulling process.
  • a hydraulic locking device is activated, which allows the pressure cheek with the workpiece to follow the movement of the ram into top dead center.
  • the next forming process - renewed movement of the press ram to the bottom dead center - can only take place after the workpiece has been removed and a new sheet metal blank has been inserted, so that there is a low output rate in drawing devices of this type.
  • DE-C-32 02 134 provides a pulling device in which the pulling force is separated from the ejector force.
  • the ejector follows the movement of the tappet with less force, corresponding to a smaller displaced volume in the ejector cylinders, while the pressure cylinder for the pulling function is initially prevented by a follow-up control device from moving to the top dead center following the movement of the tappet.
  • other measures such as. B. introduced in the upper part of the pacifier, required.
  • the invention has for its object to provide a drawing apparatus in which the individual functions - control of the sheet metal holder (drawing) pressure, control of the sheet metal holder upward movement, control of the ejector (bringer) upward movement and control of the end position stop - can be set or controlled independently of each other.
  • the workpiece and drawing apparatus are coupled via the sheet metal holder, the pressure rods and the pressure cheek only by gravity.
  • the pulling device enables the upward movement of the pressure cheek or the pressure rods to be delayed to eject less than 1 g.
  • the remaining velocity is below 0.1 m / sec. adjustable so that the workpieces can be detected by the workpiece transfer device when it is at a standstill directly after the ejector movement has been completed.
  • the adjustment measures of the single functions do not influence each other.
  • the pressure in the individual support points of the sheet metal holder can also be set differently from one another.
  • the arrangement of the pressure cylinders and the auxiliary cylinders on a common press-fixed bracket and the lifting (releasing) of the pressure cheek for ejecting the piston rods which cause the sheet metal holding during the drawing serve to improve the control of the ejection of the workpieces and the good adjustability of the drawing and ejection processes.
  • the drawing device can be fully automatically adjusted to other workpiece shapes and thicknesses of the sheet metal blanks.
  • the arrangement of the components of the overrun control devices to form functional blocks and in the areas close to the cylinder avoids moving pressure lines of large cross-sections, and also creates shorter flow paths and shorter switching times.
  • the drawing apparatus shown as an example in the drawing shows in its construction a pressure cheek 1 which is movable in sliding guides 2.
  • the slide guides 2 are located on the pressure cheek 1 and in the table of a press, step press and the like.
  • z. B a drawing station for forming flat sheet metal blanks.
  • the pressure rods 15 indicated above the pressure cheek 1 transmit the sheet metal holding force and the ejector movement to the lower tool part lying on the press table.
  • the pressure cheek 1 is supported by means of piston rods 6, 7 and by means of ball sockets 3 and spherical caps 4 inserted between pressure cheek 1 and piston rods 6, 7 in the direction of the arrows 14.
  • the piston rods 6 can be detached from the underside of the pressure cheek 1 and the pressure cheek 1 can be brought up without it into a raised position (top dead center), which corresponds to the removal position for the workpieces.
  • the pressure cylinders 8, 9 are installed above a press-fixed bracket 11 fastened in the press table.
  • the auxiliary cylinders 16, 17 are installed below the bracket 11 and coaxially with the associated pressure cylinder 8, 9.
  • the piston rods 6, 7 are also led out from the respective pressure cylinder 8, 9 on the underside and through the bracket 11 and the associated auxiliary cylinder 16, 17.
  • the piston rods 6, 7 thus interact with pistons 12, 13 in the pressure cylinders 8, 9 and with pistons 18, 19 in the auxiliary cylinders 16, 17.
  • the console 11 accommodates the control block 20 for overrun control devices 48, 49, which will be described in detail below.
  • the representation of the overrun control devices 48, 49 has priority.
  • the pistons 18, 19 which are displaceable in the auxiliary cylinders 16, 17 are mounted so as to be adjustable in the direction of the longitudinal axis thereof via a movement thread on a threaded attachment 32 in the end part 23, 24 of the piston rod 6 or 7.
  • a worm wheel 28 can be rotated into the wall of each auxiliary cylinder 16, 17 and cannot be displaced axially relative to the piston rod 6, 7, each worm wheel 28 being operatively connected to one of the pistons 18, 19 in the manner via a feather key 29 and a longitudinal groove 31, that when a rotary shaft 27 and the screw, not shown, attached to it, is rotated by an actuator 26, the axial position of the pistons 18, 19 in the auxiliary cylinders 16, 17 is adjusted with respect to the piston rod 6 and 7, respectively, so that the end position of the Adjust piston rods 6, 7 with respect to their top dead center.
  • An actuator 36, 37 is carried along with the pistons 18, 19 in the direction of the movement of the piston rods 6, 7.
  • the actuators 36, 37 are placed on control cams 38, 39 on mechanically actuable valves 52, 54 and are guided in the area of their control cams 38, 39 in the bracket 11 - hatched surface sections.
  • the piston rods 6, 7 are secured against rotation by keys 33 held in the cylinder covers 34 and guided in longitudinal grooves 41 of the end parts 23, 24 of the piston rods 6, 7.
  • the force required for sheet metal holding during drawing is to be applied in the pressure cylinders 8 and in some cases also in the pressure cylinder 9 via the pre-set pressure gas boilers 45, 46, 47.
  • the pressure in the pressure gas boilers 45, 46, 47 and the pressure chambers 5 and 10 leads without a follow-up control to the direct running of the pressure cheek 1 on the press ram moved back to the top dead center.
  • the pressure cylinders 8, 9 are connected via the pressure chambers 21, 22 of the auxiliary cylinders 16, 17 overrun control devices 48, 49, which cause the piston rods 6 and 7 to start up at different times to move the tappet to the top dead center. Due to the different design (equipping) of the follow-up control devices 48 and 49, a separation of the (deliverer) ejector process by means of the pressure in the pressure chamber 10 of the printing cylinder 9 from the run-up of the printing cylinders 8, which largely effect the sheet metal holding, is possible.
  • a control throttle 53 which adjusts its opening cross-section under the secondary pressure of the valve 54 (adjusting throttle) which opens mechanically via the control cam (39).
  • the secondary pressure of the control throttle 53 is set by the control throttle 54 in accordance with the movement of the piston 19 via the control cam 39.
  • the pressure can, with an appropriate design of the curve shape in z. B. three stages can be set so that different flow cross sections and thus differently large flow quantities can be controlled with this two-way flow control. For example, the ejector force and speed in the first phase are possible with low throttle losses with the net output force of the compressed gas boiler 47.
  • the second phase can bring about a pressure build-up counteracting the pressure in the pressure chamber 10, which leads to the end of the frictional connection between the pressure cheek 1, pressure rods 15, ejector parts of the tool and press ram.
  • the third phase can be designed in such a way that the workpiece is brought into the removal position (transport plane) at a constant pressure by further closing the control throttle 54 and consequently increased secondary pressure at the control throttle 53, which value corresponds to less than 1 g.
  • Control throttle 53 and control throttle 54 form a two-way current control from their shown and functional structure.
  • a two-way flow control comprising a regulating throttle 59 and an adjusting throttle 60 connected in series to it is introduced, by means of which the piston rods 6 run up under the pressure in the pressure gas boilers 45, 46 jammed air pressure (adjustable) is controllable.
  • the point in time at which the regulation is started can be set via the check valve 52 actuated by the control cam 38.
  • a switching valve 44 is introduced into line 42, by means of which the pressure circuits of the individual pressure cylinders 8, which exert the pulling force, can be separated from one another.
  • the drawing back pressure in the individual drawing areas of a sheet metal holder on the tool side can thus be varied and adjusted to the drawing conditions by means of different air pressures in the pressure gas boilers 45, 46.

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  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Shaping Metal By Deep-Drawing, Or The Like (AREA)

Description

Die Erfindung betrifft einen Ziehapparat an Pressen nach dem Oberbegriff des Anspruchs 1, wie z. B. aus der DE-C-32 02 134 bekannt geworden ist.The invention relates to a drawing device on presses according to the preamble of claim 1, such as. B. has become known from DE-C-32 02 134.

Ziehapparate dienen der Erzeugung der Blechhaltekraft während des Blechumformens (Ziehen) und der Erzeugung der Auswerferbewegung (Hochbringen) des geformten Werkstückes in Pressen und Transferpressen. Ziehapparate weisen eine Druckwange auf, die beim Verfahren des Pressenstößels in den unteren Totpunkt - Endbereich des Umformvorganges - über Druckstangen unter Aufbringung der Blechhaltekraft verdrängt wird und der Bewegung des Stößels in den oberen Totpunkt - dem werkzeugfernen Bereich - unter Mitnahme des geformten Werkstückes folgt. Die Kraft des Ziehapparates, während die Druckwange der Bewegung des Stößels in den oberen Totpunkt folgt, ist etwa gleichgroß der Blechhaltekraft beim Werkstückumformen. Die Werkstücke werden infolgedessen beim Auswerfen über die Druckstangen gegen das Werkzeugoberteil gedrückt und können deformiert werden.Drawers are used to generate the sheet metal holding force during sheet metal forming (drawing) and to generate the ejector movement (raising) of the shaped workpiece in presses and transfer presses. Drawers have a pressure cheek, which is displaced by moving the press ram into bottom dead center - end area of the forming process - via pressure rods with the application of the sheet metal holding force and follows the movement of the ram into top dead center - the area away from the tool - taking the formed workpiece with it. The force of the drawing device, while the pressure cheek follows the movement of the ram into the top dead center, is approximately the same as the sheet metal holding force during workpiece forming. As a result, the workpieces are pressed against the upper part of the tool when they are ejected via the push rods and can be deformed.

Bei der Einrichtung nach der DE-A-27 42 405 wird zur Vermeidung der Deformierung der Werkstücke ein Ziehapparat verwendet mit einer gesteuert, der Bewegung des Stößels in dessen oberen Totpunkt nachlaufenden Druckwange. Hierbei drückt der Pressenstößel die Druckwange wie bei dem ungesteuerten Ziehvorgang in den unteren Totpunkt. Mit dem Erreichen des unteren Totpunktes wird eine hydraulische Sperrvorrichtung angesteuert, die die Druckwange mit dem Werkstück verzögert zur Bewegung des Stößels in den oberen Totpunkt folgen läßt. Der nächste Umformvorgang - erneutes Verfahren des Pressenstößels in den unteren Totpunkt - kann erst nach der Werkstückentnahme und dem Einlegen eines neuen Blechzuschnittes erfolgen, so daß sich bei Ziehapparaten dieser Art eine geringe Ausstoßquote ergibt.In the device according to DE-A-27 42 405, a drawing apparatus is used to avoid the deformation of the workpieces with a pressure cheek that follows the movement of the ram in its top dead center. Here, the press ram presses the pressure cheek into the bottom dead center as in the uncontrolled pulling process. When the bottom dead center is reached, a hydraulic locking device is activated, which allows the pressure cheek with the workpiece to follow the movement of the ram into top dead center. The next forming process - renewed movement of the press ram to the bottom dead center - can only take place after the workpiece has been removed and a new sheet metal blank has been inserted, so that there is a low output rate in drawing devices of this type.

Zur Erhöhung der Ausstoßquote sieht die DE-C-32 02 134 einen Ziehapparat vor, bei dem die Ziehkraft von der Auswerferkraft getrennt wird. Nach dem Umformen des Blechzuschnittes folgt der Auswerfer mit geringerer Kraft der Bewegung des Stößels entsprechend einem geringeren verdrängten Volumen in den Auswerferzylindern, während der Druckzylinder für die Ziehfunktion von einer Nachlaufregeleinrichtung zunächst an einer der Bewegung des Stößels folgenden Bewegung in den oberen Totpunkt gehindert ist. Es befinden sich mehrere Auswerferzylinder auf einer verfahrbaren Druckwange. Das Werkstück wird mit der Geschwindigkeit der Stößelrücklaufbewegung in die Entnahmestellung gebracht. Zur Verhinderung unerwünschter Bewegungen des Werkstückes aus dem Werkzeugunterteil sind andere Maßnahmen, wie z. B. im Werkzeugoberteil eingebrachte Beruhigungsstifte, erforderlich.To increase the ejection rate, DE-C-32 02 134 provides a pulling device in which the pulling force is separated from the ejector force. After the sheet metal blank has been formed, the ejector follows the movement of the tappet with less force, corresponding to a smaller displaced volume in the ejector cylinders, while the pressure cylinder for the pulling function is initially prevented by a follow-up control device from moving to the top dead center following the movement of the tappet. There are several ejector cylinders on a movable pressure cheek. The workpiece is brought into the removal position at the speed of the ram return movement. To prevent undesirable movements of the workpiece from the lower part of the tool, other measures, such as. B. introduced in the upper part of the pacifier, required.

Ausgehend von einem Ziehapparat nach dem Oberbegriff des Anspruchs 1 liegt der Erfindung die Aufgabe zugrunde, einen Ziehapparat zu schaffen, bei dem die Einzelfunktionen - Steuerung des Blechhalter-(Zieh-) Druckes, Steuerung der Blechhalteraufwärtsbewegung, Steuerung der Auswerfer-(Hochbringer-) Aufwärtsbewegung und Steuerung des Endlagenanschlages - voneinander unabhängig einstellbar bzw. steuerbar sind.Starting from a drawing apparatus according to the preamble of claim 1, the invention has for its object to provide a drawing apparatus in which the individual functions - control of the sheet metal holder (drawing) pressure, control of the sheet metal holder upward movement, control of the ejector (bringer) upward movement and control of the end position stop - can be set or controlled independently of each other.

Diese Aufgabe ist durch die kennzeichnenden Merkmale des Anspruchs 1 gelöst.This object is achieved by the characterizing features of claim 1.

Die Merkmale der weiteren Ansprüche kennzeichnen wesentliche Ausgestaltungen innerhalb der Erfindung.The features of the further claims characterize essential configurations within the invention.

Die Kupplung von Werkstück und Ziehapparat erfolgt über den Blechhalter, die Druckstangen und die Druckwange nur durch Schwerkraft. Der Ziehapparat ermöglicht auslegungsgemäß eine Verzögerung der Aufwärtsbewegung der Druckwange bzw. der Druckstangen zum Auswerfen von weniger als 1 g. Die restliche Anschlaggeschwindigkeit ist auf Werte unter 0,1 m/sek. einstellbar, so daß die Werkstücke von der Werkstückumsetzeinrichtung in deren Stillstand erfaßbar sind direkt nach vollendeter Auswerferbewegung. Die Verstellmaßnahmen der Einzeifunktionen beeinflussen sich nicht gegenseitig. So ist auch der Druck in den Einzelabstützpunkten des Blechhalters unterschiedlich zueinander einstellbar. Die Anordnung der Druckzylinder und der Hilfszylinder auf einer gemeinsamen pressenfesten Konsole und das Abheben (Lösen) der Druckwange zum Auswerfen von den die Blechhaltung bei dem Ziehen bewirkenden Kolbenstangen dienen der verbesserten Steuerung des Auswerfens der Werkstücke und der guten Einstellbarkeit der Zieh- und Auswerfervorgänge. Der Ziehapparat ist vollautomatisch auf andere Werkstückformen und Dicken der Blechzuschnitte einstellbar. Die Anordnung der Bauteile der Nachlaufregeleinrichtungen zu Funktionsblöcken und in den zylindernahen Bereichen vermeidet bewegliche Druckleitungen großer Querschnitte, schafft darüber hinaus kürzere Fließwege und kürzere Schaltzeiten.The workpiece and drawing apparatus are coupled via the sheet metal holder, the pressure rods and the pressure cheek only by gravity. According to the design, the pulling device enables the upward movement of the pressure cheek or the pressure rods to be delayed to eject less than 1 g. The remaining velocity is below 0.1 m / sec. adjustable so that the workpieces can be detected by the workpiece transfer device when it is at a standstill directly after the ejector movement has been completed. The adjustment measures of the single functions do not influence each other. The pressure in the individual support points of the sheet metal holder can also be set differently from one another. The arrangement of the pressure cylinders and the auxiliary cylinders on a common press-fixed bracket and the lifting (releasing) of the pressure cheek for ejecting the piston rods which cause the sheet metal holding during the drawing serve to improve the control of the ejection of the workpieces and the good adjustability of the drawing and ejection processes. The drawing device can be fully automatically adjusted to other workpiece shapes and thicknesses of the sheet metal blanks. The arrangement of the components of the overrun control devices to form functional blocks and in the areas close to the cylinder avoids moving pressure lines of large cross-sections, and also creates shorter flow paths and shorter switching times.

Weitere besondere Vorteile bestehen darin, daß die Aufwärtsbewegung der Druckzylinder für die Blechhaltung bei konstanter Geschwindigkeit und der Aufwärtshub des Auswerferbetriebes geschwindigkeitsreguliert unabhängig von der eingestellten Blechhalterkraft bei konstanter, kleiner Kraft erfolgt. Die Steuerungsvarianten ergeben verlustarme Endlagendämpfungen (geringe Drosselverluste). Weitere wesentliche Vorteile ergeben sich aus dem z. B. dreiphasengesteuerten Auswerferbetrieb, indem während der Auswerferbewegung der Kraftschluß zwischen der Druckwange, den Druckstangen und dem Werkstück zum Stößel aufgehoben wird. Bei gleichbleibender Auswerferkraft ist die Auswerfergeschwindigkeit regulierbar.Further particular advantages are that the upward movement of the pressure cylinders for sheet metal holding at a constant speed and the upward stroke of the ejector operation are speed-controlled regardless of the set sheet metal holder force at a constant, small force. The control variants result in low-loss end position damping (low throttle losses). Other significant advantages result from the z. B. three-phase controlled ejector operation by lifting the frictional connection between the pressure cheek, the pressure rods and the workpiece to the plunger during the ejector movement. The ejector speed can be regulated while maintaining the ejector force.

Der in der Zeichnung beispielhaft dargestellte Ziehapparat zeigt in seinem Aufbau eine Druckwange 1, die in Gleitführungen 2 beweglich ist. Die Gleitführungen 2 befinden sich an der Druckwange 1 sowie im Tisch einer Presse, Stufenpresse u. dgl. mit z. B. einer Ziehstation zum Umformen flacher Blechzuschnitte. Die oberhalb der Druckwange 1 angedeuteten Druckstangen 15 übertragen die Blechhaltekraft und die Auswerferbewegung auf das auf dem Pressentisch aufliegende Werkzeugunterteil. Die Druckwange 1 wird über Kolbenstangen 6, 7 sowie über zwischen Druckwange 1 und Kolbenstangen 6, 7 eingebrachte Kugelpfannen 3 und Kalotten 4 in Richtung der Pfeile 14 abgestützt. Die Kolbenstangen 6 sind von der Unterseite der Druckwange 1 lösbar und die Druckwange 1 ist ohne diese in eine hochgefahrene Stellung (oberer Totpunkt), die der Entnahmestellung für die Werkstücke entspricht, hochbringbar. Die Druckzylinder 8, 9 sind oberhalb einer pressenfesten - im Pressentisch befestigten - Konsole 11 installiert. Die Hilfszylinder 16, 17 sind unterhalb der Konsole 11 und koaxial zu dem zugeordneten Druckzylinder 8, 9 installiert. Die Kolbenstangen 6, 7 sind aus dem jeweiligen Druckzylinder 8, 9 auch unterseitig herausgeführt und durch die Konsole 11 und den zugehörenden Hilfszylinder 16, 17 hindurchgeführt. Die Kolbenstangen 6, 7 wirken so mit Kolben 12, 13 in den Druckzylindern 8, 9 und mit Kolben 18, 19 in den Hilfszylindem 16, 17 zusammen. Die Konsole 11 nimmt den im einzelnen noch zu beschreibenden Steuerblock 20 für Nachlaufregeleinrichtungen 48, 49 auf. Bei der Darstellung der Konsole 11 hat die Darstellung der Nachlaufregeleinrichtungen 48, 49 Vorrang. Die in den Hilfszylindern 16, 17 verschieblichen Kolben 18, 19 sind über ein Bewegungsgewinde an einem Gewindeansatz 32 im Endteil 23, 24 der Kolbenstange 6 bzw. 7 in Richtung der Längsachse dieser verstellbar gelagert. In die Wandung jedes Hilfszylinders 16, 17 ist je ein Schneckenrad 28 drehbar und axial zur Kolbenstange 6, 7 nicht verschieblich eingelassen, wobei jedes Schneckenrad 28 über eine Paßfeder 29 und eine Längsnut 31 mit einem der Kolben 18, 19 in der Weise wirkverbunden ist, daß bei Drehung einer Drehwelle 27 und der an dieser befestigten, nicht dargestellten Schnecke durch einen Stellmotor 26 die axiale Lage der Kolben 18, 19 in den Hilfszylindern 16, 17 in Bezug auf die Kolbenstange 6 bzw. 7 verstellt wird, um so die Endlage der Kolbenstangen 6, 7 bezüglich ihres oberen Totpunktes einzustellen. Mit den Kolben 18, 19 sind jeweils ein Stellglied 36, 37 in Richtung der Bewegung der Kolbenstangen 6, 7 mitgeführt. Die Stellglieder 36, 37 sind über Steuerkurven 38, 39 an mechanisch betätigbare Ventile 52, 54 gelegt und im Bereich ihrer Steuerkurven 38, 39 in der Konsole 11 - schraffierte Flächenabschnitte - geführt. Die Kolbenstangen 6, 7 sind gegen Verdrehung über in den Zylinderdeckeln 34 gehaltene und in Längsnuten 41 der Endteile 23, 24 der Kolbenstangen 6, 7 geführte Paßfedern 33 gesichert.The drawing apparatus shown as an example in the drawing shows in its construction a pressure cheek 1 which is movable in sliding guides 2. The slide guides 2 are located on the pressure cheek 1 and in the table of a press, step press and the like. Like with z. B. a drawing station for forming flat sheet metal blanks. The pressure rods 15 indicated above the pressure cheek 1 transmit the sheet metal holding force and the ejector movement to the lower tool part lying on the press table. The pressure cheek 1 is supported by means of piston rods 6, 7 and by means of ball sockets 3 and spherical caps 4 inserted between pressure cheek 1 and piston rods 6, 7 in the direction of the arrows 14. The piston rods 6 can be detached from the underside of the pressure cheek 1 and the pressure cheek 1 can be brought up without it into a raised position (top dead center), which corresponds to the removal position for the workpieces. The pressure cylinders 8, 9 are installed above a press-fixed bracket 11 fastened in the press table. The auxiliary cylinders 16, 17 are installed below the bracket 11 and coaxially with the associated pressure cylinder 8, 9. The piston rods 6, 7 are also led out from the respective pressure cylinder 8, 9 on the underside and through the bracket 11 and the associated auxiliary cylinder 16, 17. The piston rods 6, 7 thus interact with pistons 12, 13 in the pressure cylinders 8, 9 and with pistons 18, 19 in the auxiliary cylinders 16, 17. The console 11 accommodates the control block 20 for overrun control devices 48, 49, which will be described in detail below. In the representation of the console 11, the representation of the overrun control devices 48, 49 has priority. The pistons 18, 19 which are displaceable in the auxiliary cylinders 16, 17 are mounted so as to be adjustable in the direction of the longitudinal axis thereof via a movement thread on a threaded attachment 32 in the end part 23, 24 of the piston rod 6 or 7. A worm wheel 28 can be rotated into the wall of each auxiliary cylinder 16, 17 and cannot be displaced axially relative to the piston rod 6, 7, each worm wheel 28 being operatively connected to one of the pistons 18, 19 in the manner via a feather key 29 and a longitudinal groove 31, that when a rotary shaft 27 and the screw, not shown, attached to it, is rotated by an actuator 26, the axial position of the pistons 18, 19 in the auxiliary cylinders 16, 17 is adjusted with respect to the piston rod 6 and 7, respectively, so that the end position of the Adjust piston rods 6, 7 with respect to their top dead center. An actuator 36, 37 is carried along with the pistons 18, 19 in the direction of the movement of the piston rods 6, 7. The actuators 36, 37 are placed on control cams 38, 39 on mechanically actuable valves 52, 54 and are guided in the area of their control cams 38, 39 in the bracket 11 - hatched surface sections. The piston rods 6, 7 are secured against rotation by keys 33 held in the cylinder covers 34 and guided in longitudinal grooves 41 of the end parts 23, 24 of the piston rods 6, 7.

Bei dem Niederfahren der Druckwange 1 als Folge der Umformbewegung des Pressenstößels verringern sich die Volumina von Druckräumen 5, 10 unterhalb der Kolbenstangen 12, 13 in den Druckzylindern 8, 9 und die hier vorhandene, druckvorgespannte Luft wird über Leitungen 42, 43 in die angeschlossenen druckeingestellten Druckgaskessel 45, 46, 47 verdrängt. Die Volumina von Druckräumen 21 22 oberhalb der Kolben 18, 19 in den Hilfszylindem 16, 17 vergrößern sich bei dem Niederfahren der Druckwange 1 und füllen sich über Leitungen 56, 57, 58 und über die Rückschlagventile 52 bzw. 55 aus einem ggf. luftvorgespannten Hydraulikspeicher 51 auf. Die Rückschlagventile 52 sind als mechanisch entsperrbare Ventile ausgelegt. Die für die Blechhaltung bei dem Ziehen erforderliche Kraft ist über die vordruckeingestellten Druckgaskessel 45, 46, 47 in den Druckzylindern 8 und zum Teil auch in dem Druckzylinder 9 aufzubringen. Der Druck in den Druckgaskesseln 45, 46, 47 und den Druckräumen 5 und 10 führt ohne eine Nachlaufregelung zum direkten Nachlaufen der Druckwange 1 auf den in den oberen Totpunkt zurückbewegten Pressenstößel.When the pressure cheek 1 is lowered as a result of the shaping movement of the press ram, the volumes of pressure chambers 5, 10 below the piston rods 12, 13 in the pressure cylinders 8, 9 decrease and the pressure-prestressed air present here is adjusted via lines 42, 43 into the connected pressure Compressed gas boiler 45, 46, 47 displaced. The volumes of pressure chambers 21 22 above the pistons 18, 19 in the auxiliary cylinders 16, 17 increase when the pressure cheek 1 is lowered and are filled via lines 56, 57, 58 and via the check valves 52 and 55 from a possibly air-preloaded hydraulic accumulator 51 on. The check valves 52 are designed as mechanically unlockable valves. The force required for sheet metal holding during drawing is to be applied in the pressure cylinders 8 and in some cases also in the pressure cylinder 9 via the pre-set pressure gas boilers 45, 46, 47. The pressure in the pressure gas boilers 45, 46, 47 and the pressure chambers 5 and 10 leads without a follow-up control to the direct running of the pressure cheek 1 on the press ram moved back to the top dead center.

Den Druckzylindern 8, 9 sind über die Druckräume 21, 22 der Hilfszylinder 16, 17 Nachlaufregeleinrichtungen 48, 49 zugeschaltet, die ein zum Verfahren des Stößels in den oberen Totpunkt zeitlich versetztes Hochfahren der Kolbenstangen 6 und 7 bewirken. Durch die unterschiedliche Auslegung (Bestückung) der Nachlaufregeleinrichtungen 48 und 49 ist eine Trennung des (Hochbringer-) Auswerfervorganges vermittels des Druckes in dem Druckraum 10 des Druckzylinders 9 von dem Hochlaufen der zum größten Teil die Blechhaltung bewirkenden Druckzylinder 8 möglich. In den Rückstrom von Hydraulikflüssigkeit aus dem Druckraum 22 des Hilfszylinders 17 zum Hydraulikspeicher 51 ist eine sich unter dem Sekundärdruck des mechanisch über die Steuerkurve (39) öffnenden Ventiles 54 (Stelldrossel) in ihrem Öffnungsquerschnitt einstellende Regeldrossel 53 eingeschaltet. Der Sekundärdruck der Regeldrossel 53 wird von der Stelldrossel 54 eingestellt entsprechend der über die Steuerkurve 39 erfolgten Bewegung des Kolbens 19. Der Druck kann bei entsprechender Auslegung der Kurvenform in z. B. drei Stufen eingestellt werden, so daß sich unterschiedliche Fließquerschnitte und somit unterschiedlich große Fließmengen mit dieser Zweiwege-Stromreglung steuern lassen. So ist beispielsweise die Auswerferkraft und - geschwindigkeit in der ersten Phase unter geringen Drosselverlusten mit der Netto-Ausbringerkraft des Druckgaskessels 47 möglich. Die zweite Phase kann bei entsprechender Auslegung der Steuerlemente einen dem Druck in dem Druckraum 10 entgegenwirkenden Druckaufbau bewirken, der zur Beendigung des Kraftschlusses zwischen Druckwange 1, Druckstangen 15, Auswerferteilen des Werkzeuges und Pressenstößels führt. Die dritte Phase ist derart auslegbar, daß das Werkstück bei Konstantdruck durch weiteres Schließen der Stelldrossel 54 und demzufolge erhöhtem Sekundärdruck an der Regeldrossel 53 mit einem Verzögern in die Entnahmestellung (Transportebene) verbracht wird, die einem Wert kleiner 1 g entspricht. Regeldrossel 53 und Stelldrossel 54 bilden von ihrem gezeigten und funktionellen Aufbau her eine Zweiwege-Stromregelung.The pressure cylinders 8, 9 are connected via the pressure chambers 21, 22 of the auxiliary cylinders 16, 17 overrun control devices 48, 49, which cause the piston rods 6 and 7 to start up at different times to move the tappet to the top dead center. Due to the different design (equipping) of the follow-up control devices 48 and 49, a separation of the (deliverer) ejector process by means of the pressure in the pressure chamber 10 of the printing cylinder 9 from the run-up of the printing cylinders 8, which largely effect the sheet metal holding, is possible. In the return flow of hydraulic fluid from the pressure chamber 22 of the auxiliary cylinder 17 to the hydraulic accumulator 51, a control throttle 53 which adjusts its opening cross-section under the secondary pressure of the valve 54 (adjusting throttle) which opens mechanically via the control cam (39). The secondary pressure of the control throttle 53 is set by the control throttle 54 in accordance with the movement of the piston 19 via the control cam 39. The pressure can, with an appropriate design of the curve shape in z. B. three stages can be set so that different flow cross sections and thus differently large flow quantities can be controlled with this two-way flow control. For example, the ejector force and speed in the first phase are possible with low throttle losses with the net output force of the compressed gas boiler 47. With a corresponding design of the control elements, the second phase can bring about a pressure build-up counteracting the pressure in the pressure chamber 10, which leads to the end of the frictional connection between the pressure cheek 1, pressure rods 15, ejector parts of the tool and press ram. The third phase can be designed in such a way that the workpiece is brought into the removal position (transport plane) at a constant pressure by further closing the control throttle 54 and consequently increased secondary pressure at the control throttle 53, which value corresponds to less than 1 g. Control throttle 53 and control throttle 54 form a two-way current control from their shown and functional structure.

In den Rückstrom von Hydraulikflüssigkeit aus den Druckräumen 21 der Hilfszylinder 16 zum gemeinsamen Hydraulikspeicher 51 ist eine Zweiwege-Stromregelung aus einer Regeldrossel 59 und einer zu dieser in Reihe geschalteten Stelldrossel 60 eingebracht, vermittels der der Hochlauf der Kolbenstangen 6 unter dem in den Druckgaskesseln 45, 46 gestauten Luftdruck (regelbar) steuerbar ist. Der Zeitpunkt des Einsetzens der Regelung ist über das von der Steuerkurve 38 betätigte Rückschlagventil 52 einstellbar. Für den Hochlauf der Kolbenstangen 6 ergeben sich somit verschiedene Varianten.In the return flow of hydraulic fluid from the pressure chambers 21 of the auxiliary cylinders 16 to the common hydraulic accumulator 51, a two-way flow control comprising a regulating throttle 59 and an adjusting throttle 60 connected in series to it is introduced, by means of which the piston rods 6 run up under the pressure in the pressure gas boilers 45, 46 jammed air pressure (adjustable) is controllable. The point in time at which the regulation is started can be set via the check valve 52 actuated by the control cam 38. There are thus different variants for the run-up of the piston rods 6.

In die Leitung 42 ist ein Schaltventil 44 eingebracht, vermittels dessen die die Ziehkraft aufbringenden Druckkreise der einzelnen Druckzylinder 8 voneinander trennbar sind. Über unterschiedlich hohe Luftdrücke in den Druckgaskesseln 45, 46 ist so der Ziehgegenhaltedruck in den einzelnen Ziehbereichen eines werkzeugseitigen Blechhalters variabel und auf die Ziehbedingungen einstellbar.A switching valve 44 is introduced into line 42, by means of which the pressure circuits of the individual pressure cylinders 8, which exert the pulling force, can be separated from one another. The drawing back pressure in the individual drawing areas of a sheet metal holder on the tool side can thus be varied and adjusted to the drawing conditions by means of different air pressures in the pressure gas boilers 45, 46.

Claims (7)

1. Drawing apparatus on presses, comprising pressure cylinders (8) for holding the sheet during drawing and at least one pressure cylinder (9) for the ejection of the workpieces, a pressure cheek (1) which is guided in the press bed and is supported in such a way that it can be lifted and lowered by the pressure cylinders (8, 9), and a follow-up regulating device (48) which regulates upward travel of the pressure cylinders (8, 9) which hold the sheet during drawing, which upward travel is delayed in relation to the upward travel of the ram of the press from bottom dead centre to top dead centre, characterized in that an auxiliary cylinder (16, 17) is in each case allocated to each of the pressure cylinders (8, 9), that the pressure cylinders (8, 9) and auxiliary cylinders (16, 17) are held on a bracket (11) fixed to the press, that the piston rods (6) of the pressure cylinders (8), during the upward travel of the pressure cheek (1), for the ejection of the workpieces, can be released from the underside of the pressure cheek (1) and, for holding the sheet, can again be placed from below against the pressure cheek (1), that the piston rod (6, 7) of each of the pressure cylinders (8, 9) is operatively connected to a piston (18, 19) of the associated auxiliary cylinder (16, 17), and that an individually adjustable follow-up regulating device (48, 49) is in each case connected to the pressure spaces (21, 22) located above the pistons (18, 19) in the auxiliary cylinders (16, 17).
2. Drawing apparatus on presses according to Claim 1, characterized in that the pressure cylinders (8) for holding the sheet and the pressure cylinders (9) for the ejection are arranged at the top on the bracket (11) fixed to the press, and that the auxiliary cylinders (16, 17) allocated to the pressure cylinders (8, 9) are arranged at the bottom on the bracket (11) fixed to the press and are arranged coaxially to the pressure cylinders (8, 9), and the piston rods (6, 7) are passed through the bracket (11) and through the auxiliary cylinders (16, 17), and the end parts (23, 24) of the piston rods (6, 7) of the pressure cylinders (8, 9) interact with height-adjusting means (18, 19, 26, 27, 28, 29, 32) common to all end parts (23, 24).
3. Drawing apparatus on presses according to Claim 1, characterized in that the pressure spaces (5) of the pressure cylinders (8) for holding the sheet are connected to a common pressure-gas vessel (46) adjustable in admission pressure, that the pressure space (10) of the pressure cylinder (9) or the pressure spaces (10) of a plurality of pressure cylinders (9) for the ejection are connected to a further pressure-gas vessel (47) adjustable in admission pressure, and that the pressure spaces (21, 22) of the auxiliary cylinders (16, 17) are each connected via their own pressure-regulating devices (48, 49) to a hydraulic-fluid reservoir (51) which is common to all and is adjustable in admission pressure.
4. Drawing apparatus on presses according to Claim 1, characterized in that the pressure spaces (5) of the pressure cylinders (8) for holding the sheet are connected independently from one another to one pressure-gas vessel (45, 46) each which can be adjusted to a different admission pressure.
5. Drawing apparatus on presses according to Claim 1, characterized in that each follow-up regulating device (48) connected to the pressure spaces (21) of the auxiliary cylinders (16) allocated to the pressure cylinders (8) for holding the sheet is a two-way flow-regulating valve, and that a non-return valve (52) which cuts off flow in the direction of the hydraulic reservoir (51) is connected in parallel with each follow-up regulating device (48).
6. Drawing apparatus on presses according to Claim 5, characterized in that the pressure space (22) of the auxiliary cylinder (17) allocated to the pressure cylinder (9) for the ejection is fluidically connected to a hydraulic reservoir (51) via a two-way flow-regulating arrangement, that the two-way flow-regulating arrangement consists of a regulating restrictor (53) and a control restrictor (54) which are connected in series with one another, that the control restrictor (54) can be varied in the cross-section of flow via a final control element (37, 39) carried along by the piston (7) of the pressure cylinder (9), and that a non-return valve (55) cutting off flow in the direction of the hydraulic reservoir (51) is connected in parallel with the two-way flow-regulating arrangement.
7. Drawing apparatus on presses according to Claim 1, characterized in that the follow-up regulating device (49) is a regulating arrangement which, with respect to the flow behaviour, reduces the throughflow in several phases.
EP86101399A 1985-02-21 1986-02-04 Drawing apparatus for presses Expired EP0192115B1 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
DE19853505984 DE3505984A1 (en) 1985-02-21 1985-02-21 DRAWER ON PRESSES
DE3505984 1985-02-21

Publications (3)

Publication Number Publication Date
EP0192115A2 EP0192115A2 (en) 1986-08-27
EP0192115A3 EP0192115A3 (en) 1987-09-16
EP0192115B1 true EP0192115B1 (en) 1989-07-19

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ID=6263125

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Application Number Title Priority Date Filing Date
EP86101399A Expired EP0192115B1 (en) 1985-02-21 1986-02-04 Drawing apparatus for presses

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US (1) US4712412A (en)
EP (1) EP0192115B1 (en)
BR (1) BR8600714A (en)
DE (2) DE3505984A1 (en)
ES (1) ES8704094A1 (en)

Families Citing this family (12)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE3640507C3 (en) * 1986-11-27 1998-01-29 Mueller Weingarten Maschf Device for controlling the sheet metal holder force during the drawing process
DE3640788A1 (en) * 1986-11-28 1988-06-01 Schuler Gmbh L DRAWING DEVICE FOR A PRESS
DE3640787A1 (en) * 1986-11-28 1988-06-01 Schuler Gmbh L DRAWING DEVICE FOR A PRESS
CH671731A5 (en) * 1987-02-13 1989-09-29 Sig Schweiz Industrieges
DE3718159A1 (en) * 1987-05-29 1988-12-15 Schuler Gmbh L Drawing apparatus on presses
DE3807683A1 (en) * 1988-03-09 1989-09-21 Schuler Gmbh L Drawing apparatus in drawing stages of presses
DE3933806A1 (en) * 1989-10-10 1991-11-14 Schuler Gmbh L DRAWER IN DRAWING STAGES OF PRESSES
DE4117102A1 (en) * 1991-05-25 1992-11-26 Schuler Gmbh L PRESS WITH DRAWING DEVICE
DE19726928A1 (en) * 1997-06-25 1999-01-07 Schuler Pressen Gmbh & Co Pulling device
US5971373A (en) * 1998-01-29 1999-10-26 Hsieh; Wen-Yuan Multi-cylinder buffer device
WO2012104442A1 (en) * 2011-01-31 2012-08-09 Azol-Gas, S. L. Gas spring
EP2824359B1 (en) * 2013-07-08 2015-07-01 Bordignon Silvano S.r.l. Compensator for unbalanced compression forces for press machines

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Publication number Priority date Publication date Assignee Title
US1503105A (en) * 1922-02-06 1924-07-29 Marquette Tool & Mfg Co Pressure pad
US1846439A (en) * 1930-12-26 1932-02-23 Fredrich J Rode Metal working press
US2300162A (en) * 1938-05-13 1942-10-27 Dominion Eng Works Ltd Hydraulic press
US2989019A (en) * 1957-05-20 1961-06-20 Budd Co Method of deep drawing sheet material
GB1092869A (en) * 1965-09-21 1967-11-29 Dro Engineering Co Di Hydraulic system for dies
US3456478A (en) * 1967-07-07 1969-07-22 Bliss Co Hydraulic locking cylinders
DE2742405A1 (en) * 1977-09-21 1979-03-22 Krupp Gmbh Drawing plant having safety locking device - with hydraulic cylinder connected by one line to an open tank
DE3202134C1 (en) * 1982-01-23 1983-07-07 Maschinenfabrik Müller-Weingarten AG, 7987 Weingarten Compressed air drawing device with a pressure cheek guided in the press table

Also Published As

Publication number Publication date
DE3664418D1 (en) 1989-08-24
ES552164A0 (en) 1987-03-16
EP0192115A2 (en) 1986-08-27
US4712412A (en) 1987-12-15
ES8704094A1 (en) 1987-03-16
BR8600714A (en) 1986-10-29
EP0192115A3 (en) 1987-09-16
DE3505984A1 (en) 1986-08-21

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