EP0114170B1 - Overload protection device in presses - Google Patents

Overload protection device in presses Download PDF

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Publication number
EP0114170B1
EP0114170B1 EP83100561A EP83100561A EP0114170B1 EP 0114170 B1 EP0114170 B1 EP 0114170B1 EP 83100561 A EP83100561 A EP 83100561A EP 83100561 A EP83100561 A EP 83100561A EP 0114170 B1 EP0114170 B1 EP 0114170B1
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EP
European Patent Office
Prior art keywords
pressure
overload
summation
piston
pressure balance
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
EP83100561A
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German (de)
French (fr)
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EP0114170A1 (en
Inventor
Werner Rupp
Johannes Koch
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L Schuler GmbH
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L Schuler GmbH
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Publication date
Application filed by L Schuler GmbH filed Critical L Schuler GmbH
Priority to DE8383100561T priority Critical patent/DE3367556D1/en
Priority to EP83100561A priority patent/EP0114170B1/en
Priority to BR8400228A priority patent/BR8400228A/en
Priority to JP59007423A priority patent/JPS59137199A/en
Priority to US06/572,305 priority patent/US4492154A/en
Priority to ES529029A priority patent/ES8501670A1/en
Publication of EP0114170A1 publication Critical patent/EP0114170A1/en
Application granted granted Critical
Publication of EP0114170B1 publication Critical patent/EP0114170B1/en
Expired legal-status Critical Current

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    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B30—PRESSES
    • B30B—PRESSES IN GENERAL
    • B30B15/00—Details of, or accessories for, presses; Auxiliary measures in connection with pressing
    • B30B15/28—Arrangements for preventing distortion of, or damage to, presses or parts thereof
    • B30B15/281—Arrangements for preventing distortion of, or damage to, presses or parts thereof overload limiting devices
    • B30B15/284—Arrangements for preventing distortion of, or damage to, presses or parts thereof overload limiting devices releasing fluid from a fluid chamber subjected to overload pressure

Definitions

  • the invention relates to an overload protection in step, transfer and the like. Presses of the type specified in the preamble of claim 1.
  • the ram nominal force to be protected by the total pressure compensator is selected to be smaller than the sum of the maximum forces of the overload stages, so that the press does not have to be dimensioned unnecessarily.
  • the sum of the tappet forces does not rule out that the working stages closer to a drive level are loaded to a maximum and the other working stages only weakly and vice versa. This requires an unnecessarily large dimensioning of the connecting rods, drive parts and stands.
  • DE-C-1288431 describes a measure for the overall protection of a press or step press in the event of an overload.
  • the press drive acts on various work stages, each of which is secured with its own overload protection, which switches off the press drive in the work stage if the limit load is exceeded.
  • the overload protection devices of the individual work stages are connected to a total overload protection device, which is therefore permanently loaded by all individual overload protection devices and whose switch-off value is set to a value that is less than the sum of the overload values of the individual overload protection devices. This device allows a high load on the drive levels and requires excessive dimensioning of the drive components.
  • DE-C-20 04 980 shows an essentially the same device for overall protection of a press or step press, each with a total overload protection for the work stages, one drive level of the ram.
  • the overload protection devices assigned to the working stages each have a pressure chamber that can be compressed under the working pressure in the working stage.
  • Each pressure chamber is in flow connection with a pressure chamber of the overload protection of the drive level, to which the work stage is assigned.
  • the switch-off value is exceeded, the pressure in the pressure chambers of the overload safety devices and the total overload safety devices is relieved via a common lockable drain line.
  • the distances of the individual work stages to the connecting rods are not taken into account and the device does not adequately protect the drive levels, as are the work stages further away from a drive level, which are not included in the associated overall overload protection, according to the Lever Act Contribute to the power at this level.
  • the connecting rods 1 engage in the drive levels 2 and 3 on the tappet 4.
  • the work stages are numbered 6, 7, 8, 9 in Fig. 1 and 10 in Fig. 2, and 83 in Fig. 3 for further arrangements.
  • Overload pressure compensators 11, 12, 13, 14 and 86 are used in the power flow between each working stage and the tappet.
  • the overload pressure compensators each have a pressure chamber 21, 22, 23, 24 and 84 and pistons 36, 37, 38, 39 and 85 immersed in them.
  • the pressure chambers 21 to 24 and 84 are with pressure chambers 26, 27, 28, .29 of a first total pressure compensator 16 and 81 and with pressure chambers 31, 32, 33, 34 one second total pressure compensator 17 or 82 in flow connection.
  • the pressure in the pressure chambers is preset, specifically from the pump unit 47 via the pressure switch 49 and the pressure limiting controller 48, the pressure supply line 52, check valves 53 and pressure lines 91 to 94 assigned to the individual systems.
  • the pretensioning pressure in the pressure chambers can be set.
  • Three pressure chambers are connected in parallel.
  • the pressure chamber 21 of the left overload pressure compensator 11, the pressure chamber 26 of the total pressure compensator 16 and the pressure chamber 31 of the total pressure compensator 17 form a pressure system.
  • the total pressure compensators 16 and 17 each have a pressure chamber 18 or 19, in which a pre-pressure is also set, which is generated by a pump unit 57 and is monitored or limited by the pressure switch 58 and the pressure limiting controller 59.
  • the pressure relief controls 54 and 61 relieve the pressure on the pressure areas, specifically whenever the pressure in an overload pressure compensator or in a total pressure compensator has exceeded a specified ratio to the preload pressure. This immediately stops the flow of power in the affected work stages.
  • the check valves 51 and 53 prevent the other pressure chambers from being relieved when one of the overload pressure compensators responds.
  • Each pressure compensator is assigned sensors 56, 62 which stop the press when the pressure compensator is triggered.
  • FIG. 2 shows with the work stage 10 an area lying outside the drive level (here 3), to be queried for tool and press ram or connecting rod safety, with an overload pressure compensator 14 which is offset by the distance 46 from the drive level 3.
  • the pressure chamber 29 communicating with the pressure chamber 24 acts with the piston 70 opposite to the other pressure chambers 26, 27, 28 of this total pressure compensator 81.
  • the pressure chamber 34, which is also connected in parallel, with the associated piston 74 of the total pressure compensator 82 has the same effect as the other pistons / pressure chambers 31, 32 , 33/71, 72, 73 of this total pressure compensator.
  • the calculation of the cross-sectional areas also of the piston 70 of the pressure balance 81 results as shown previously. Is the distance between the working levels 8 and.
  • the piston cross sections of the pistons 70 and 68 are of the same size.
  • their forces acting on the balance pressure compensator 81 do not cancel each other out because the pressures in the working stages do not have to be the same size during the press load.
  • a force thus moves the piston 20 into the pressure chamber 18, which is reduced by the cross section of the piston 70 multiplied by the pressure in the pressure chamber 29, for the total pressure compensator 81.
  • the piston cross-sectional calculation of the associated piston 74 of the total pressure compensator 82 is also calculated here from the distance 46 of the working stage 10 from the drive plane 2 and the cross section of the piston 39 of the overload pressure compensator 14.
  • the work stages 6 to 10 of the embodiments described above are connected, for example, to the pressure lines 91, 93, 94 and possibly further pressure lines Total pressure compensator 88 connected.
  • the sum pressure compensator can also be designed like the sum pressure compensators 16 or 81 of FIGS. 1 and 2, or replace them or the sum pressure compensators 17 and 82, specifically when the working stage 83 is located in the middle of the drive level 2.
  • the admission pressure in the pressure compensator 86 is set via the line 87 coming from the pump assembly 47 as well as the check valves and, as is also possible in the previous examples, by means of pressure limiting monitors.
  • the admission pressure is at the same time on the line 92, which leads into a section 64 which is shut off by the plungers 66 and 67 or the plungers 67 and 68 by the outlet line 63 leading to the outside.
  • the section 64 is always released when the total forces acting on the piston 89 via the plungers 66, 67 and 68 are greater than the force resulting from the pressure in the pressure chamber 90 with the projected area of the piston 89.

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  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Control Of Presses (AREA)

Description

Die Erfindung betrifft eine Überlastsicherung in Stufen-, Transfer- und dgl. Pressen der im Oberbegriff des Anspruches 1 angegebenen Art.The invention relates to an overload protection in step, transfer and the like. Presses of the type specified in the preamble of claim 1.

Bei den angeführten Pressen mit hydraulisch wirkenden Überlastsicherungsmaßnahmen in den einzelnen Arbeitsstufen, die gemeinsam auf eine Summendruckwaage des Stößels wirken, wird die durch die Summendruckwaage abzusichernde Stößelnennkraft kleiner gewählt als die Summe der Maximalkräfte der Überlaststufen, damit die Presse nicht unnötig stark dimensioniert werden muß. Im allgemeinen werden nicht alle Arbeitsstufen mit ihrer Maximalkraft gleichzeitig belastet. Diese niedrigere Begrenzung der Summe der Stößelkräfte schließt aber noch nicht aus, daß die einer Antriebsebene näher gelegenen Arbeitsstufen maximal und die übrigen Arbeitsstufen nur schwach belastet werden und umgekehrt. Dies erfordert eine unnötig starke Dimensionierung der Pleuel, Antriebsteile und Ständer.In the presses with hydraulic overload protection measures in the individual work stages, which act together on a total pressure compensator of the ram, the ram nominal force to be protected by the total pressure compensator is selected to be smaller than the sum of the maximum forces of the overload stages, so that the press does not have to be dimensioned unnecessarily. In general, not all work stages are loaded with their maximum power at the same time. However, this lower limitation of the sum of the tappet forces does not rule out that the working stages closer to a drive level are loaded to a maximum and the other working stages only weakly and vice versa. This requires an unnecessarily large dimensioning of the connecting rods, drive parts and stands.

In der allgemeinen Beschreibung zur DE-C-1246652 sind Sicherungsmaßnahmen in Pressen, Stufenpressen u. dgl. unter Verwendung eines Grenzkraftorganes beschrieben worden. In der Regel führt die Auslösung dieser Mittel bei Überlast in den einzelnen Arbeitsstufen oder bei Überschreiten einer Gesamtüberlast zu einem Abschalten der Presse.In the general description of DE-C-1246652 security measures in presses, step presses and. The like. Has been described using a limit force member. As a rule, the triggering of these means in the event of an overload in the individual work stages or when a total overload is exceeded, the press is switched off.

Die DE-C-1288431 beschreibt eine Maßnahme zur Gesamtabsicherung einer Presse oder Stufenpresse bei Überlast. Der Pressenantrieb wirkt hierbei auf verschiedene Arbeitsstufen ein, die jede für sich mit einer eigenen Überlastsicherung abgesichert sind, die bei Grenzlastüberschreitung in der Arbeitsstufe den Pressenantrieb abschalten. Darüber hinaus sind die Überlastsicherungen der einzelnen Arbeitsstufen an eine Gesamtüberlastsicherung angeschlossen, die also von allen Einzelüberlastsicherungen dauernd beaufschlagt wird und deren Abschaltwert auf einen Wert eingestellt ist, der kleiner ist als die Summe der Überlastwerte der Einzelüberlastsicherungen. Diese Einrichtung läßt eine hohe Belastung der Antriebsebenen zu und erfordert eine übermäßige Dimensionierung der Antriebsbauteile.DE-C-1288431 describes a measure for the overall protection of a press or step press in the event of an overload. The press drive acts on various work stages, each of which is secured with its own overload protection, which switches off the press drive in the work stage if the limit load is exceeded. In addition, the overload protection devices of the individual work stages are connected to a total overload protection device, which is therefore permanently loaded by all individual overload protection devices and whose switch-off value is set to a value that is less than the sum of the overload values of the individual overload protection devices. This device allows a high load on the drive levels and requires excessive dimensioning of the drive components.

Die DE-C-20 04 980 zeigt eine im wesentlichen gleiche Einrichtung zur Gesamtabsicherung einer Presse oder Stufenpresse mit je einer Gesamtüberlastsicherung für die Arbeitsstufen je einer Antriebsebene des Stößels. Die den Arbeitsstufen zugeordneten Überlastsicherungen weisen hierbei jeweils einen unter dem Arbeitsdruck in der Arbeitsstufe komprimierbaren Druckraum auf. Jeder Druckraum steht mit einem Druckraum der Überlastsicherung der Antriebsebene in Fließverbindung, der die Arbeitsstufe zugeordnet ist. Im Überlastfall, bei Überschreiten des Abschaltwertes, wird der Druck in den Druckräumen der Überlastsicherungen und der Gesamtüberlastsicherungen über eine gemeinsame absperrbare Ablaßleitung entlastet. In den Berechnungen für die Sicherungsmaßnahmen finden die Abstände der einzelnen Arbeitsstufen zu den Pleueln keine Berücksichtigung und die Einrichtung sichert die Antriebsebenen insofern nicht ausreichend ab, als auch die von einer Antriebsebene entfernter liegenden Arbeitsstufen, die in die zugehörige Gesamtüberlastsicherung nicht einbezogen sind, nach dem Hebelgesetz Anteile zur Kraft in dieser Ebene beitragen.DE-C-20 04 980 shows an essentially the same device for overall protection of a press or step press, each with a total overload protection for the work stages, one drive level of the ram. The overload protection devices assigned to the working stages each have a pressure chamber that can be compressed under the working pressure in the working stage. Each pressure chamber is in flow connection with a pressure chamber of the overload protection of the drive level, to which the work stage is assigned. In the event of an overload, if the switch-off value is exceeded, the pressure in the pressure chambers of the overload safety devices and the total overload safety devices is relieved via a common lockable drain line. In the calculations for the safety measures, the distances of the individual work stages to the connecting rods are not taken into account and the device does not adequately protect the drive levels, as are the work stages further away from a drive level, which are not included in the associated overall overload protection, according to the Lever Act Contribute to the power at this level.

Demgegenüber ist es Aufgabe der Erfindung, die Pleuel sowie Getriebeteile und Ständer von Pressen, insbesondere von Pressen mit in zwei Ebenen angetriebenen Pressenstößeln, auch für unsymmetrische Belastungsfälle des Pressenstößels nach den den Pleueln eigenen Grenzlastwerten abzusichern und die als Folge der einzelnen Abstände der Arbeitsstufen zu den Pleueln auftretenden Kraftmomente hierbei zu erfassen.In contrast, it is an object of the invention to secure the connecting rods as well as gear parts and stands of presses, in particular of presses with press rams driven in two planes, even for asymmetrical load cases of the press ram according to the limit load values specific to the connecting rods and as a result of the individual distances of the working stages to the Force rods occurring here to be recorded.

Diese Aufgabe wird durch die im Ansprüche 1 angegebenen Merkmale gelöst.This object is achieved by the features specified in claims 1.

Dabei ist von Vorteil, daß auch ein geringer Lastfall in einer entfernt von dem Pleuel, auf den sich die Querschnittsberechnung der Kolben in den Summendruckwaagen bezieht, auftretenden Arbeitsstufe beim Überschreiten der Grenzlast der Pleuel und somit zur Signalabgabe bzw. zum Abschalten einbezogen wird.It is advantageous that even a small load case in a working stage that occurs distant from the connecting rod, to which the cross-sectional calculation of the pistons in the summation pressure compensators relates, is included when the connecting rod's limit load is exceeded and thus for signaling or switching off.

Die Ausgestaltungen nach den Merkmalen der Ansprüche 2 bis 4 erfassen die Überlastsicherung der Presse mit außerhalb des zwischen den Antriebsebenen gebildeten Stößelbereiches, jedoch von einem Stößel mit beaufschlagten Arbeitsstufen sowie eine Arbeitsstufe in der Antriebesebene.The configurations according to the features of claims 2 to 4 detect the overload protection of the press with outside of the ram area formed between the drive levels, but of a ram with working stages and a working level in the drive level.

In vorteilhafter Weise kann die Sicherheitseinrichtung für die beanspruchten Anwendungsfälle derart berechnet sein, daß der Grenzwert der Stößelkraft gleich der Summe der Grenzwerte der Pleuelkräfte und eine zusätzliche Summendruckwaage für den Stößel nicht notwendig ist. Im folgenden soll die Erfindung anhand der in den Figuren dargestellten Ausführungsbeispiele beschrieben werden. Es zeigen

  • Figur 1 eine Überlastsicherung nach der Erfindung in schematisierter Darstellung,
  • Figur 2 eine zweite Ausgestaltung der Überlastsicherung nach der Erfindung mit außerhalb einer Antriebsebene befindlicher Arbeitsstufe und
  • Figur 3 eine weitere Ausgestaltung der Überlastsicherung nach der Erfindung mit einer in einer Antriebsebene angeordneten Arbeitsstufe.
In an advantageous manner, the safety device for the claimed applications can be calculated in such a way that the limit value of the tappet force, equal to the sum of the limit values of the connecting rod forces, and an additional total pressure compensator for the tappet are not necessary. The invention will be described below with reference to the exemplary embodiments shown in the figures. Show it
  • FIG. 1 shows an overload protection according to the invention in a schematic illustration,
  • Figure 2 shows a second embodiment of the overload protection according to the invention with a working level located outside a drive level and
  • Figure 3 shows a further embodiment of the overload protection according to the invention with a working stage arranged in a drive level.

In den Figuren greifen die Pleuel 1 in den Antriebsebenen 2 und 3 am Stößel 4 an. Die Arbeitsstufen sind mit 6, 7, 8, 9 in Fig. 1 sowie mit 10 in Fig. 2, und 83 in Fig. 3 für weitere Anordnungen beziffert. Im Kraftfluß zwischen jeder Arbeitsstufe und dem Stößel sind Überlastdruckwaagen 11, 12, 13, 14 sowie 86 eingesetzt. Die Überlastdruckwaagen weisen je einen Druckraum 21, 22, 23, 24 und 84 sowie in diese eintauchende Kolben 36, 37, 38, 39 und 85 auf. Die Druckräume 21 bis 24 und 84 stehen mit Druckräumen 26, 27, 28,.29 einer ersten Summendruckwaage 16 bzw. 81 und mit Druckräumen 31, 32, 33, 34 einer zweiten Summendruckwaage 17 bzw. 82 in Fließverbindung. Der Druck in den Druckräumen ist voreingestellt, und zwar von dem Pumpenaggregat 47 ausgehend über den Druckwächter 49 und den Druckbegrenzungsregler 48, die Druckversorgungsleitung 52, Rückschlagventile 53 und den einzelnen Systemen zugeordneten Druckleitungen 91 bis 94. Der Vorspanndruck in den Druckräumen ist einstellbar. Es sind jeweils drei Druckräume parallel geschaltet. So bilden beispielsweise der Druckraum 21 der linken Überlastdruckwaage 11, der Druckraum 26 der Summendruckwaage 16 und der Druckraum 31 der Summendruckwaage 17 ein Drucksystem. Die Summendruckwaagen 16 und 17 weisen je einen Druckraum 18 bzw. 19 auf, in denen gleichfalls ein Vordruck eingestellt ist, der von einem Pumpenaggregat 57 erzeugt wird und über den Druckwächter 58 und den Druckbegrenzungsregler 59 überwacht bzw. begrenzt wird. Über die Druckablaßregelungen 54 und 61 werden die Druckräume gezielt entlastet, und zwar immer dann, wenn der Druck in einer Überlastdruckwaage oder in einer Summendruckwaage ein festgelegtes Verhältnis zum Vorspanndruck überschritten hat. Dadurch wird der Kraftfluß in den betroffenen Arbeitsstufen sofort unterbrochen. Die Rückschlagventile 51 und 53 verhindern ein Entlasten der übrigen Druckräume bei Ansprechen einer der Überlastdruckwaagen. Jeder Druckwaage sind Sensoren 56, 62 zugeordnet, die beim Auslösen der Druckwaage die Presse stillsetzen.In the figures, the connecting rods 1 engage in the drive levels 2 and 3 on the tappet 4. The work stages are numbered 6, 7, 8, 9 in Fig. 1 and 10 in Fig. 2, and 83 in Fig. 3 for further arrangements. Overload pressure compensators 11, 12, 13, 14 and 86 are used in the power flow between each working stage and the tappet. The overload pressure compensators each have a pressure chamber 21, 22, 23, 24 and 84 and pistons 36, 37, 38, 39 and 85 immersed in them. The pressure chambers 21 to 24 and 84 are with pressure chambers 26, 27, 28, .29 of a first total pressure compensator 16 and 81 and with pressure chambers 31, 32, 33, 34 one second total pressure compensator 17 or 82 in flow connection. The pressure in the pressure chambers is preset, specifically from the pump unit 47 via the pressure switch 49 and the pressure limiting controller 48, the pressure supply line 52, check valves 53 and pressure lines 91 to 94 assigned to the individual systems. The pretensioning pressure in the pressure chambers can be set. Three pressure chambers are connected in parallel. For example, the pressure chamber 21 of the left overload pressure compensator 11, the pressure chamber 26 of the total pressure compensator 16 and the pressure chamber 31 of the total pressure compensator 17 form a pressure system. The total pressure compensators 16 and 17 each have a pressure chamber 18 or 19, in which a pre-pressure is also set, which is generated by a pump unit 57 and is monitored or limited by the pressure switch 58 and the pressure limiting controller 59. The pressure relief controls 54 and 61 relieve the pressure on the pressure areas, specifically whenever the pressure in an overload pressure compensator or in a total pressure compensator has exceeded a specified ratio to the preload pressure. This immediately stops the flow of power in the affected work stages. The check valves 51 and 53 prevent the other pressure chambers from being relieved when one of the overload pressure compensators responds. Each pressure compensator is assigned sensors 56, 62 which stop the press when the pressure compensator is triggered.

Auch die Druckleitungen 92, 93 und 94 verbinden die Druckräume zusammengehörender Drucksysteme. Die Summendruckwaagen 16 und 17 weisen einerseits Kolben 66 bis 74 und 89 auf, die in die Druckräume 26 bis 29 und 31 bis 34 und 90 eintauchen und andererseits Kolben 20 und 25 in den Druckräumen 18 und 19. Die Kolben 66 bis 74 weisen Querschnitte (Durchmesser) unterschiedlicher Größe auf proportional und in Abhängigkeit vom Abstand der jeweils zugeordneten Überlastdruckwaage bzw. der Arbeitsstufe zu der Antriebsebene 2 bzw. 3 multipliziert mit dem Kolbenquerschnitt der Überlastdruckwaage. Die Entfernungen der Überlastdruckwaagen (Arbeitsstufen) zu der Antriebsebene 3 sind mit 41 bis 44 beziffert; die dementsprechenden Entfernungen der Überlastdruckwaagen (Arbeitsstufen) zu der Antriebsebene 2 sind mit 79 bis 76 gekennzeichnet. Bei gleicher Querschnittsfläche der Kolben 36, 37, 38, 39 und 85 sind die Querschnittsflächen der Kolben 66, 67, 68, 69, 70 der links gezeichneten Summendruckwaage 16 proportional zum Abstand der Mitte der jeweils zugehörenden Arbeitsstufe zur Antriebsene 3. So ergibt sich für die Arbeitsstufe 6 über dem zugehörenden Abstand 41 eine hieraus herleitbare große Kolbenfläche des Kolbens 66 für die Arbeitsstufe 9 mit dem zugehörenden Abstand 44 eine proportional zum Abstand 41 kleinere Querschnittsfläche des Kolbens 69. Die Berechnung der Kolbenquerschnitte der Kolben 71 bis 74 der Summendruckwaage 17 erfolgt in analoger Weise. Sie sind proportional zum Abstand der zugehörigen Arbeitsstufe von der Antriebsebene 2. Die von jedem Pleuel aufzunehmende Kraft ergibt sich aus der Auflagerberechnung für zwei Auflager und hier vier zu den Antriebsebenen beabstandeten Kräften. Jede dieser Kräfte kann zum Abschalten der Presse über die Sensoren 56 führen, ohne daß der Grenzwert eines Pleuels in der zuordnungsbaren Summendruckwaage überschritten wurde. Demgegenüber schaltet jede Summendruckwaage ab, wenn der Grenzwert eines Pleuels überschritten wird, ohne daß eine der Überlastdruckwaagen in einer diese schaltenden Weise belastet wurde, wenn also die Summe der einzelnen Überlastdruckwaagen den Grenzwert überschreitet. Die Kolben 66 bis 69 der Summendruckwaage 16 können dabei, wie in Fig. 3 dargestellt, eine Leitung freigeben, durch welche die Druckräume aller Arbeitsstufen 21 bis 24 u. 84 zugleich druckfrei werden. Entsprechendes gilt bei Ansprechen der Summendruckwaage 17 für die Kolben 71 bis 74. Bei unterschiedlichen Querschnittsflächen der Kolben 36, 37, 38, 39 und 85 errechnen sich die Kolbenquerschnitte für die Kolben 66 bis 69 aus dem Verhältnis

Figure imgb0001
wobei

  • Psgr der Abschaltdruck in einer Summendruckwaage,
  • A, die Querschnittsfläche des Gegenkolbens (hier 20),
  • A; die Querschnittsfläche des Kolbens im Druckraum der i-ten Arbeitsstufe,
  • Fplgr der Grenzwert der Kraft in dem der Berechnung zugeordneten Pleuel,
  • IP der Abstand der Antriebsebenen voneinander und
  • y; der zugehörende Abstand 41 bis 44 bzw. 76 bis 79 ist.
Pressure lines 92, 93 and 94 also connect the pressure spaces of associated pressure systems. The sum pressure balances 16 and 17 have pistons 66 to 74 and 89 on the one hand, which plunge into the pressure chambers 26 to 29 and 31 to 34 and 90 and on the other hand pistons 20 and 25 in the pressure chambers 18 and 19. The pistons 66 to 74 have cross sections ( Diameter) of different sizes to proportional and depending on the distance of the respectively assigned overload pressure compensator or the working level to the drive level 2 or 3 multiplied by the piston cross section of the overload pressure compensator. The distances of the overload pressure compensators (working stages) to the drive level 3 are numbered 41 to 44; the corresponding distances of the overload pressure compensators (working stages) to drive level 2 are marked 79 to 76. With the same cross-sectional area of the pistons 36, 37, 38, 39 and 85, the cross-sectional areas of the pistons 66, 67, 68, 69, 70 of the total pressure compensator 16 shown on the left are proportional to the distance between the center of the respective working stage and the drive end 3. This results in for the working stage 6 over the associated distance 41 a large piston surface of the piston 66 which can be derived therefrom for the working stage 9 with the associated distance 44 a smaller cross-sectional area of the piston 69 proportional to the distance 41. The piston cross sections of the pistons 71 to 74 of the total pressure compensator 17 are calculated in FIG analogous way. They are proportional to the distance of the associated working stage from the drive level 2. The force to be absorbed by each connecting rod results from the support calculation for two supports and here four forces spaced from the drive levels. Each of these forces can cause the press to be switched off via the sensors 56 without the limit value of a connecting rod in the assignable total pressure compensator being exceeded. In contrast, each total pressure compensator switches off when the limit value of a connecting rod is exceeded without one of the overload pressure compensators being loaded in a switching manner, that is, when the sum of the individual overload pressure compensators exceeds the limit value. The pistons 66 to 69 of the total pressure compensator 16 can, as shown in FIG. 3, release a line through which the pressure spaces of all working stages 21 to 24 u. 84 become pressure-free at the same time. The same applies correspondingly when the total pressure compensator 17 responds for the pistons 71 to 74. With different cross-sectional areas of the pistons 36, 37, 38, 39 and 85, the piston cross sections for the pistons 66 to 69 are calculated from the ratio
Figure imgb0001
 in which
  • Ps g r the cut-off pressure in a total pressure balance,
  • A, the cross-sectional area of the opposing piston (here 20),
  • A ; the cross-sectional area of the piston in the pressure chamber of the i-th stage,
  • Fp l g r the limit value of the force in the connecting rod assigned to the calculation,
  • I P is the distance between the drive levels and
  • y ; the associated distance is 41 to 44 or 76 to 79.

Fig. 2 zeigt mit der Arbeitsstufe 10 einen außerhalb der Antriebsebene (hier 3) liegenden, auf Werkzeug- und Pressenstößel- bzw. Pleuelsicherheit abzufragenden Bereich mit einer Überlastdruckwaage 14, die um den Abstand 46 zur Antriebsebene 3 versetzt ist. Der mit dem Druckraum 24 kommunizierende Druckraum 29 wirkt mit dem Kolben 70 entgegengesetzt zu den übrigen Druckräumen 26, 27, 28 dieser Summendruckwaage 81. Der gleichfalls parallelgeschaltete Druckraum 34 mit zugehörendem Kolben 74 der Summendruckwaage 82 ist gleichwirkend wie die weiteren Kolben/Druckräume 31, 32, 33/71, 72, 73 dieser Summendruckwaage. Die Berechnung der Querschnittsflächen auch des Kolbens 70 der Summendruckwaage 81 ergibt sich wie zuvor aufgezeigt. Ist der Abstand der Arbeitsstufen 8 und. 10 zur Antriebsebene 3 bei gleich großen Querschnitten der Kolben 38 und 39 gleich groß, so ergeben sich gleichgroße Kolbenquerschnitte der Kolben 70 und 68. Ihre auf die Summendruckwaage 81 wirkenden Kräfte heben sich jedoch nicht unbedingt auf, weil die Drücke in den Arbeitsstufen während der Pressenbelastung nicht gleich groß sein müssen. Für die Summendruckwaage 81 stellt sich somit eine den Kolben 20 in den Druckraum 18 bewegende Kraft ein, die um den Querschnitt des Kolbens 70 multipliziert mit dem Druck in dem Druckraum 29 verringert ist. Die Kolbenquerschnittsberechnung des zugehörenden Kolbens 74 der Summendruckwaage 82 berechnet sich auch hier aus dem Abstand 46 der Arbeitsstufe 10 von der Antriebsebene 2 und dem Querschnitt des Kolbens 39 der Überlastdruckwaage 14.2 shows with the work stage 10 an area lying outside the drive level (here 3), to be queried for tool and press ram or connecting rod safety, with an overload pressure compensator 14 which is offset by the distance 46 from the drive level 3. The pressure chamber 29 communicating with the pressure chamber 24 acts with the piston 70 opposite to the other pressure chambers 26, 27, 28 of this total pressure compensator 81. The pressure chamber 34, which is also connected in parallel, with the associated piston 74 of the total pressure compensator 82 has the same effect as the other pistons / pressure chambers 31, 32 , 33/71, 72, 73 of this total pressure compensator. The calculation of the cross-sectional areas also of the piston 70 of the pressure balance 81 results as shown previously. Is the distance between the working levels 8 and. 10 to the drive level 3 with the same size cross sections of the pistons 38 and 39, the piston cross sections of the pistons 70 and 68 are of the same size. However, their forces acting on the balance pressure compensator 81 do not cancel each other out because the pressures in the working stages do not have to be the same size during the press load. A force thus moves the piston 20 into the pressure chamber 18, which is reduced by the cross section of the piston 70 multiplied by the pressure in the pressure chamber 29, for the total pressure compensator 81. The piston cross-sectional calculation of the associated piston 74 of the total pressure compensator 82 is also calculated here from the distance 46 of the working stage 10 from the drive plane 2 and the cross section of the piston 39 of the overload pressure compensator 14.

Fig. 3 geht ein auf die Möglichkeit einer sich mittig zu einer der Antriebsebenen, hier Antriebsebene 3, befindlichen Arbeitsstufe 83. Die Arbeitsstufen 6 bis 10 der vorherig beschriebenen Ausführungen sind über beispielsweise die Druckleitungen 91, 93, 94 und ggf. weiterer Druckleitungen an der Summendruckwaage 88 angeschlossen. Die Summendruckwaage kann auch wie die Summendruckwaagen 16 bzw. 81 der Fig. 1 und 2, ausgeführt sein oder diese oder die Summendruckwaagen 17 und 82 ersetzen, und zwar dann, wenn sich die Arbeitsstufe 83 mittig zu der Antriebsebene 2 befindet. Der Vordruck in der Druckwaage 86 wird über die von dem Pumpenaggregat 47 kommende Leitung 87 sowie die Rückschlagventile und, wie auch in den vorhergehenden Beispielen möglich, durch Druckbegrenzungswächter eingestellt. Der Vordruck liegt gleichzeitig auf der Leitung 92, die in einen durch die Plungerkolben 66 und 67 oder die Plungerkolben 67 und 68 von der nach außen führenden Ablaßleitung 63 abgesperrten Teilstück 64 führt. Das Teilstück 64 wird immer dann freigegeben, wenn die auf den Kolben 89 über die Plungerkolben 66, 67 und 68 einwirkenden Gesamtkräfte größer sind als die sich aus dem Druck in dem Druckraum 90 mit der projizierten Fläche des Kolbens 89 ergebende Kraft.3 goes into the possibility of a work stage 83 located centrally to one of the drive levels, here drive level 3. The work stages 6 to 10 of the embodiments described above are connected, for example, to the pressure lines 91, 93, 94 and possibly further pressure lines Total pressure compensator 88 connected. The sum pressure compensator can also be designed like the sum pressure compensators 16 or 81 of FIGS. 1 and 2, or replace them or the sum pressure compensators 17 and 82, specifically when the working stage 83 is located in the middle of the drive level 2. The admission pressure in the pressure compensator 86 is set via the line 87 coming from the pump assembly 47 as well as the check valves and, as is also possible in the previous examples, by means of pressure limiting monitors. The admission pressure is at the same time on the line 92, which leads into a section 64 which is shut off by the plungers 66 and 67 or the plungers 67 and 68 by the outlet line 63 leading to the outside. The section 64 is always released when the total forces acting on the piston 89 via the plungers 66, 67 and 68 are greater than the force resulting from the pressure in the pressure chamber 90 with the projected area of the piston 89.

Das Entlasten aller Druckräume sowie der diese verbindenden Leitungen nach einem Abschalten der Presse, Mehrstufenpresse oder Pressenstraße erfolgt vermittels der elektrisch, pneumatisch oder vorteilhafter Weise hydraulisch betätigbaren Ventile 54 und 61.All pressure chambers and the lines connecting them are relieved after the press, multi-stage press or press line has been switched off by means of the electrically, pneumatically or advantageously hydraulically actuated valves 54 and 61.

Claims (4)

1. Overload protection in multiple-die, transfer or such like presses with push rods (4) driven by connecting rods (1) on a first drive level (2) and on a second drive level (3) remote from the first drive level, and acting at operational stages (6, 7, 8, 9, 10, 83), each operational stage being assigned at least one overload pressure ballance (11, 12, 13, 14, 86) with one pressure space each (21, 22, 23, 24, 84) and each pressure space (21, 22, 23, 24, 84) being connected to a pressure space (26, 27, 28, 29) of a first summation pressure balance (16, 81, 88) or to a pressure space (31, 32, 33, 34) of a second summation pressure balance (17, 82) and the value of the total overload protection of each summation pressure balance (16, 17, 81, 82, 88) being set smaller than the sum of the values of the individual overload protections of the overload pressure balances (11, 12, 13, 14, 86), characterized in that in the first summation pressure balance (16, 81, 88) are arranged equivalent in number to pressure spaces (26, 27, 28, 29) the number of operational stages (6, 7, 8, 9,10, 83) and in the second summation pressure balance (17, 82) are arranged equivalent in number to pressure spaces (31, 32, 33, 34) the number of operational stages (6, 7, 8, 9, 10, 83), in that each pressure space (21, 22, 23, 24, 84) of each overload pressure balance (11, 12, 13, 14, 86) is connected to one pressure space each (26, 27, 28, 29) of the first summation pressure balance (16, 81, 88) and to one pressure space each (31, 32, 33, 34) of the second summation pressure balance (17, 82), and in that the cross-section of each piston (66, 67, 68, 69, 70) impinged in the first summation pressure balance (16, 81, 88) is proportional to the product of the distance (41, 42, 43, 44, 46) of the connected operational stage (6, 7, 8, 9, 10, 83) from the second drive level (3) and the piston cross-section of the overload pressure balance (21, 22, 23, 24, 84), and the cross-section of each piston (71, 72, 73, 74) impinged in the second summation pressure balance (17, 82) is proportional to the product of the distance (76, 77, 78, 79) of the connected operational stage (6, 7, 8, 9, 10, 83) from the first drive level (2) and the piston cross-section of the overload pressure balance (21, 22, 23, 24, 84).
2. Overload protection in accordance with Patent Claim 1, with at least one operational stage (10) located outside of one of the drive levels (2, 3) of a push rod (4), but impinged by the latter, characterized in that the piston (70) of the (first) summation pressure balance (81) which is connected to the overload pressure balance (14) of the operational stage (10) and the piston area calculation of which relates to the drive level, in this case (3), to which the operational stage (10) is to be assigned as the nearest, is arranged acting in the opposite direction to the pistons (66, 67, 68) impinged by the other overload pressure balances (6, 7, 8).
3. Overload protection according to Patent Claim 1, with at least one operational stage (83), lying substantially central to a drive level (3), characterized in that the pressure line (87) led out from the pressure space (84) of the overload pressure balance (86) assigned to the operational stage (83) is connected not only to the pressure admission means (47) establishing the preliminary pressure in the pressure space (84) but also to the pressure outlet control (54), which relieves the line (87) and the pressure space (84) from pressure when a limit value is exceeded.
4. Overload protection according to Patent Claim 3, with an outlet line (63) for the pressure medium, cleared simultaneously with the pressure lines (91, 93, 94) by the movement of the summation piston (89) when the press is switched off, characterized in that the pressure line (87) led out of the pressure space (84) of the overload pressure balance (86) is connected to a section (64) of the outlet line (63) which can be shut off by two neighbouring pistons (67, 68).
EP83100561A 1983-01-22 1983-01-22 Overload protection device in presses Expired EP0114170B1 (en)

Priority Applications (6)

Application Number Priority Date Filing Date Title
DE8383100561T DE3367556D1 (en) 1983-01-22 1983-01-22 Overload protection device in presses
EP83100561A EP0114170B1 (en) 1983-01-22 1983-01-22 Overload protection device in presses
BR8400228A BR8400228A (en) 1983-01-22 1984-01-19 SAFETY AGAINST PRESS OVERLOAD
JP59007423A JPS59137199A (en) 1983-01-22 1984-01-20 Safety device for overload in press
US06/572,305 US4492154A (en) 1983-01-22 1984-01-20 Overload protection in presses
ES529029A ES8501670A1 (en) 1983-01-22 1984-01-20 Overload protection device in presses.

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
EP83100561A EP0114170B1 (en) 1983-01-22 1983-01-22 Overload protection device in presses

Publications (2)

Publication Number Publication Date
EP0114170A1 EP0114170A1 (en) 1984-08-01
EP0114170B1 true EP0114170B1 (en) 1986-11-12

Family

ID=8190252

Family Applications (1)

Application Number Title Priority Date Filing Date
EP83100561A Expired EP0114170B1 (en) 1983-01-22 1983-01-22 Overload protection device in presses

Country Status (6)

Country Link
US (1) US4492154A (en)
EP (1) EP0114170B1 (en)
JP (1) JPS59137199A (en)
BR (1) BR8400228A (en)
DE (1) DE3367556D1 (en)
ES (1) ES8501670A1 (en)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE102013210807A1 (en) 2013-06-10 2014-12-11 Gräbener Pressensysteme GmbH & Co. KG Overload release device in a servo press

Families Citing this family (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS62151300A (en) * 1985-12-26 1987-07-06 Komatsu Ltd Over load protecting device for press machine
DE4036470A1 (en) * 1990-11-15 1992-05-21 Mueller Weingarten Maschf Mechanical press overload protection system
DE4110761C1 (en) * 1991-04-03 1992-04-02 Harald Perchtoldsdorf At Engel
DE59305912D1 (en) * 1993-02-02 1997-04-24 Putzmeister Maschf METHOD FOR CONVEYING PRE-CRUSHED METAL SCRAP OR THE SAME SOLID CONTAINING SOLIDS
US5638748A (en) * 1996-01-25 1997-06-17 The Minster Machine Company Hydraulic overload proportional valving system for a mechanical press
DE19847890C1 (en) * 1998-10-16 2000-02-10 Siempelkamp Gmbh & Co Intermittent press in one or more levels for board prodn has groups of piston/cylinders linked to medium and low pressure vessels which have a closed nitrogen supply system to prevent or eliminate nitrogen loss
JP6554217B2 (en) * 2018-08-09 2019-07-31 コマツ産機株式会社 Control system, press machine, and control method of press machine

Family Cites Families (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE1288431B (en) * 1965-12-10 1969-01-30 Weingarten Ag Maschf Total overload protection of a press
FR2075436A5 (en) * 1970-02-04 1971-10-08 Weingarten Ag Maschf
DE2828315A1 (en) * 1978-06-28 1980-01-10 Paul Chrubasik Press table support - has hydraulic cylinder assembly acting against force of press ram

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE102013210807A1 (en) 2013-06-10 2014-12-11 Gräbener Pressensysteme GmbH & Co. KG Overload release device in a servo press
EP2813357A1 (en) 2013-06-10 2014-12-17 Gräbener Pressensysteme GmbH & Co. KG Overload release device in a servo press

Also Published As

Publication number Publication date
ES529029A0 (en) 1984-12-01
DE3367556D1 (en) 1987-01-02
JPS59137199A (en) 1984-08-07
US4492154A (en) 1985-01-08
BR8400228A (en) 1984-08-28
EP0114170A1 (en) 1984-08-01
ES8501670A1 (en) 1984-12-01

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