EP0335939A1 - Dispositif hydraulique d'entrainement - Google Patents

Dispositif hydraulique d'entrainement

Info

Publication number
EP0335939A1
EP0335939A1 EP88908928A EP88908928A EP0335939A1 EP 0335939 A1 EP0335939 A1 EP 0335939A1 EP 88908928 A EP88908928 A EP 88908928A EP 88908928 A EP88908928 A EP 88908928A EP 0335939 A1 EP0335939 A1 EP 0335939A1
Authority
EP
European Patent Office
Prior art keywords
pressure
valve
drive
piston
hydraulic cylinder
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.)
Granted
Application number
EP88908928A
Other languages
German (de)
English (en)
Other versions
EP0335939B1 (fr
Inventor
Eckehart Schulze
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.)
Individual
Original Assignee
Individual
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 Individual filed Critical Individual
Priority to AT88908928T priority Critical patent/ATE60113T1/de
Publication of EP0335939A1 publication Critical patent/EP0335939A1/fr
Application granted granted Critical
Publication of EP0335939B1 publication Critical patent/EP0335939B1/fr
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

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
    • B21D28/00—Shaping by press-cutting; Perforating
    • B21D28/002—Drive of the tools
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B30—PRESSES
    • B30B—PRESSES IN GENERAL
    • B30B15/00—Details of, or accessories for, presses; Auxiliary measures in connection with pressing
    • B30B15/16—Control arrangements for fluid-driven presses

Definitions

  • the invention relates to a hydraulic drive device for a machine element, e.g. a punching or embossing tool which, in the course of a machining cycle of a workpiece, executes a rapid feed movement leading to it with the same direction of movement, then the working stroke and then a rapid return movement returning to the starting position, and with the further ones mentioned in the preamble of patent claim 1 , generic characteristics.
  • a machine element e.g. a punching or embossing tool which, in the course of a machining cycle of a workpiece, executes a rapid feed movement leading to it with the same direction of movement, then the working stroke and then a rapid return movement returning to the starting position, and with the further ones mentioned in the preamble of patent claim 1 , generic characteristics.
  • the operating pressure-dependent switchover from rapid feed mode to load feed mode is often selected, i.e. if the pressure in the drive pressure chambers of the differential cylinder exceeds a threshold value, it is controlled by means of a pressure-controlled area - Switchover valve switched from rapid feed operation to load feed operation.
  • the pressure-controlled valve could be considered to equip the pressure-controlled valve with an electromagnetic hold control in such a way that it is additionally provided with a control magnet which, as soon as the valve - depending on the pressure - changes from rapid feed operation to load feed -Operation is switched, the valve for a defined period of time in the functional position mediating the load-feed operation holds.
  • a control magnet which, as soon as the valve - depending on the pressure - changes from rapid feed operation to load feed -Operation is switched, the valve for a defined period of time in the functional position mediating the load-feed operation holds.
  • the object of the invention is therefore to improve a hydraulic drive device of the type mentioned in such a way that a need-based switchover of the drive device from rapid feed operation to load feed operation and from this again to rapid feed operation or final rapid withdrawal operation, independently on the thickness of a workpiece to be machined.
  • the surface switching valve provided below as an exclusively pressure-dependent controlled valve, in which the response pressure can be defined in a defined manner by the closing force of a check valve which can be set according to claim 2, in combination with a directional valve which, as it were, generates the "hysteresis" that is required
  • a significant advantage over known drive devices is obtained from the point of view of saving time and achieved a high level of functional reliability due to the simplicity of the overall structure.
  • Fig. 1 is a schematic representation of a hydraulic drive device according to the invention, in which the drive element and the surface switching valve are each shown in section along their central longitudinal axes and
  • the hydraulic drive device according to the invention shown in FIG. 1, to the details of which is expressly referred to, designated overall by 10, is assumed without restriction of generality as a drive head for a punching or embossing machine, in which as a drive element for a tool 11, by means of which a workpiece 12, e.g. a steel plate which can be subjected to a penetrating or shaping cold deformation, a hydraulic cylinder designated as a whole is provided, which in the special embodiment shown is designed as a double-acting, linear hydraulic cylinder.
  • This hydraulic cylinder 13 is assumed to be arranged as "standing”, i.e. with a vertical course of its central longitudinal axis 14 with respect to a horizontally arranged machine table 16, by which the machine frame, not shown in the rest, is represented, on which, fixed to the frame, the housing 17 of the hydraulic cylinder 13 is also permanently mounted.
  • the workpiece 12 resting on the machine table 16 can be fixed to the machine table 16 by means of a holding device (not shown).
  • the hydraulic cylinder 13 is designed as a differential cylinder whose piston 18, which can be displaced up and down, within the cylinder bore 19 delimits two drive pressure chambers 21 and 22 in a pressure-tight manner from one another, through their valve-controlled, joint or alternative application of the output pressure P, one with a total of 23 designated pressure supply unit and, if necessary, pressure relief of each of the two drive pressure chambers 21 or 22, the feed and retraction strokes of the piston 18 or the tool 11 required for the machining of workpieces 12 can be controlled as required.
  • the effective amount of the piston surface 24 which delimits the movable piston pressure space 21 according to the illustration in FIG. 1 is equal to the cross-sectional area F 1 of the cylinder bore 19.
  • K 1 F 1 . P (1).
  • F 2 is the effective cross-sectional area of the cylinder bore 19, in which the cylinder piston 18 is displaceably guided in a pressure-tight manner, designated by an inner housing step housing bore 29, in which the piston 18, which is fixedly connected to the piston 18 and is, for example, embodied in one piece with it, is displaceably guided in a pressure-tight manner, at the lower, free end of which the tool 11 is fastened.
  • F 3 denotes the effective amount of the essentially circular “differential area” 32 on which a pressure coupled into the lower drive pressure chamber 22 acts on the cylinder piston 18 in the sense of generating the force K 2 .
  • the area ratio F 1 / F 3 has the value 2/1.
  • the maximum amount of this feed force K 3 is - at the value 2/1 of the area ratio F 1 / F 3 chosen for the explanation - limited to 50% of the maximum achievable feed force K 1 , which can be achieved if only the upper drive pressure chamber 21 is acted upon by the outlet pressure P of the auxiliary pressure source 23, but the lower drive pressure chamber 22 is relieved to the tank 34 of the pressure supply unit 23.
  • the lower drive pressure chamber 22 is acted upon by the outlet pressure of the pressure supply unit 23 and the upper drive pressure chamber 21 toward the tank 34 of the pressure supply unit 23 relieved, which consists of a high-pressure pump 36 and a pressure relief valve 37 that can be adjusted to a desired outlet pressure range, as shown in FIG.
  • an electrically controllable directional control valve 38 is provided, which has a neutral center position "centered" by return springs 39 and 41, in the basic position 0, in which the Pressure supply unit 23 works in circulation.
  • this directional control valve 38 can be controlled, in each case from its basic position, into alternative functional positions I or II, one of which - the functional control I of the feed direction of the piston movement and its others - the functional position II - the withdrawal direction of the piston or tool movement are assigned.
  • the control signals required for the motion control for the control magnets 42 and 43 of the directional control valve 38 are generated by a driver stage 44, which in turn can be electronically controlled manually, for example via hand switches (not shown) or automatically in the sense of the required motion sequence.
  • the directional control valve 38 is designed as a 3/3-way valve, via which only the connection of the drive pressure chamber 21, which is larger in cross-section, as shown in FIG. 1, is either connected to the high-pressure outlet 46 of the pressure supply Unit 23 or at its tank port 47 is controllable.
  • This surface switch valve 53 which is shown in FIG. 1 in its basic position corresponding to the non-activated state of the drive device 10, is, on the one hand, a pressure-controlled directional valve which, depending on the pressures in the drive pressure chambers 21 and 22 of the drive hydraulic cylinder 13 prevail, automatically as required, the connection of the annular drive pressure chamber 22 of the hydro Cylinder to the high-pressure outlet 46 of the pressure supply unit 23 conveys in which case the maximum feed force that can be used for machining the workpiece 12 is given by the relationship (3), but a relatively high feed speed can be used for this, alternatively the pressure relief of this drive pressure chamber 22 conveyed to the tank 34 of the pressure supply unit 23 when an increased feed force is required for the machining of the workpiece 12, the maximum amount of which is given by the relationship (1), but in which case the feed speed that can then still be used by a factor of F 3 / F 1 is reduced.
  • this surface switch valve 53 fulfills the function that after it had been switched into its functional position which mediated the pressure relief of the annular drive pressure chamber 22 and thereby enabled the use of an increased feed force, only then again in its pressurization of the annular drive pressure chamber 22 mediating function position is switched back after the - for example penetrating - machining of the workpiece 12 the need for feed force on the tool 11 has become a defined minimum amount ⁇ K lower than the amount of the feed force or the operating pressure in the drive pressure chambers 21 and 22 of the hydraulic cylinder 13 , by exceeding which the switching of the surface switching valve 53 in which the pressure relief of the annular drive pressure chamber 22 was triggered.
  • the surface switching valve 53 is designed in more detail as follows:
  • the surface switching valve 53 comprises a first valve chamber 57, which is permanently connected to the tank connection 47 of the pressure supply unit 53 via a relief flow path 58 and is thus kept depressurized.
  • valve chamber 57 is sealed off from the outside with a set screw, as it were, which forms the end end wall of the valve 61, which is denoted overall by 59.
  • a valve closing spring 62 is adjustable, which engages a centering piece 63, which urges a valve body formed as a ball 64 of a seat valve, generally designated 66, against its valve seat 67, ie into the closed position of this seat valve 66, which is formed by the inner, ie the clear diameter towards the smaller edge of a conical depression, which in turn serves to center the valve ball 64, of an intermediate wall 69 of the valve housing 59.
  • a valve channel 72 opening into the central valve chamber 71 extends between this valve seat 67 and a central valve chamber 71.
  • the central valve chamber 71 is in constant communication via a first hydraulic control line 73 Connection to the annular drive pressure chamber 22 of the hydraulic cylinder 13.
  • the central valve chamber 71 is bounded by the one bore step 74, the diameter of which is smaller, of a stepped bore of the housing 59, which is designated overall by 76, the diameter of which is larger at the other end of the housing 59 is sealed in a pressure-tight manner by a housing cover 78 which forms the end wall of the valve housing 59 there.
  • a stage piston In the two bore stages 74 and 77 of the stage bore 76, a stage piston, designated overall by 82, is displaceably guided in a pressure-tight manner with a piston stage 79 and 81, respectively, the smaller piston stage 79 of which forms an axially movable boundary of the central valve chamber 71, and its diameter after the larger piston stage 81, on the one hand, the axially movable boundary of an annular chamber 85 forms, which is axially fixed to the housing by the annular housing stage 83 mediating between the smaller bore stage 74 and the larger bore stage 77, and further the axially movable boundary of a control chamber 84 forms, the housing-fixed axial boundary is formed by the housing cover 78.
  • This control chamber 84 is held via a second hydraulic line S 86 in constant communication with the larger drive pressure chamber 21 of the drive hydraulic cylinder 13.
  • the stepped piston 82 is urged toward the valve ball 64 by a - weakly preloaded - return spring 87, which is supported on the inside of the housing cover 78, on which it is shown in FIG. 1 made basic position with a plunger-shaped, axial extension of its smaller piston stage 79 supports.
  • the outer diameter of this push-egg-shaped extension 88 is significantly smaller than the diameter of the valve channel 72 through which it passes.
  • the smaller piston stage 79 is offset from the larger piston stage 81 by an annular groove-shaped constriction 89 which is penetrated by a transverse bore 91 opening into the annular chamber 85.
  • This transverse bore 91 is in constant communication with the central valve chamber 71 via a central longitudinal bore 92 which penetrates the smaller piston stage 79 and its plunger-shaped extension 88 in the axial direction and one or more transverse bore (s) 93 in the plunger-shaped extension 88.
  • the smaller bore step 74 seen in the axial direction, is provided in its central region with an annular groove-shaped, radial extension 94, which is permanently connected to the high-pressure outlet 46 of the pressure supply unit 23 via a third control or pressure supply line 95.
  • the edge formed by the radially inner edge 96 of the upper groove flank 97 facing the central valve chamber 71 in accordance with FIG. 1 forms a control edge fixed to the housing, with which the outer edge 98 of the annular end face 99 of the smaller piston stage 79 delimiting the central valve chamber 51 cooperates as a movable control edge can.
  • the movable control edge 98 of the stepped piston 82 has a positive overlap with the control edge 96 fixed to the housing, this overlap ⁇ X 1 only a small fraction corresponds to the stroke X 1 that the stepped piston 82 can carry out from its illustrated basic position in the opening direction of the seat valve 66, ie in the direction of arrow 101, and also only a small fraction of that stroke X 2 that the stepped piston 82 in the opposite direction, ie can execute in the direction of arrow 102.
  • the annular chamber delimited by the annular groove-shaped extension 94 and the smaller piston step 59 regardless of the overlap ⁇ X 1 of the movable control edge 98 and the control edge 96 fixed to the housing, is not hermetically sealed against the central valve chamber 71, but stands with it a peripheral edge notch 103 with a small overflow cross-section still in communicating connection, which is however canceled when the stepped piston joins has performed a small fraction of its possible stroke in the direction of arrow 101, after which the annular groove-shaped extension 94 of the smaller bore step 74 communicating with the high-pressure outlet 46 of the pressure supply unit 23 is blocked off from the central valve chamber 71.
  • the preload of the valve closing spring 62 is or is set so high that the force with which the valve ball 64 is pressed against the circular valve seat 67 corresponds approximately to the force, for example 90% of that force, if the valve ball 66 within the by the Valve seat 67 bordered circular area with the maximum output pressure of the pressure supply unit 23 is applied. Assuming a maximum outlet pressure of the pressure supply unit 23 of 300 bar, the pretensioning of the closing spring 62 is accordingly set to a "closing pressure" of 270 bar equivalent value set.
  • the bias of the return spring 87 is negligible and equivalent to a pressure of only a few, for example 5 bar.
  • A is a predeterminable fraction of the area ratio of the order of 20%, by which the area ratio F 5 / F 4 should always be greater than the area ratio F 1 / F 3 of the areas of the piston 18 of the hydraulic cylinder 13 that can be pressurized.
  • the drive device 10 explained in terms of its structure works more specifically as follows: When the pressure supply unit 23 is switched on, the directional control valve 38 is first controlled in its energized position II. As a result, the larger drive pressure chamber 21 of the hydraulic cylinder 13 and the control chamber 84 of the surface switching valve 53 to the tank 34 of the pressure supply unit 23 are relieved, while at the same time the output pressure of the pressure supply unit 23 into the annular groove-shaped extension 94 of the Housing 59 of the surface switching valve 53, the central valve chamber 71 and the annular chamber 85 and via the first control line 73 is coupled into the annular drive pressure chamber 22 of the hydraulic cylinder 13. The piston 18 of the hydraulic cylinder 13 thereby initially reaches its upper end position, the basic position shown in FIG.
  • step piston 82 of the surface switching valve 53 which is in total on one of the cross-sectional area F 5 of its larger piston step 81 with the outlet pressure of the pressure supply Actuated, is pushed into its lower end position, shown in FIG. 2, ie removed from the valve ball 64.
  • This functional position of the surface switching valve 53 in combination with the excited position II of the directional control valve 38 also corresponds to the retracting operation of the hydraulic cylinder 18 after the tool 11 has carried out its working stroke.
  • the directional control valve 38 In order to initiate its feed operation from the basic position of the hydraulic cylinder piston 18, the directional control valve 38 is switched into its functional position I by energizing its first control magnet 42. As a result, both the upper drive pressure chamber 21 of the hydraulic cylinder 13 and the control chamber 84 of the surface switching valve 53 are connected to the high-pressure outlet 46 of the pressure supply unit 23 via the flow-through flow path 49 of the directional control valve 38.
  • the stepped piston 82 of the surface switching valve 53 is now relieved of pressure, since it is pressurized with neutral pressure both via the central valve chamber 71 and the annular chamber 85 and via the control chamber 84 with the outlet pressure P of the pressure supply unit.
  • the weak return spring 87 is now able to To shift the stepped piston in the direction of the valve ball 64, but the stepped piston remains held in a dynamic overlap of these control edges by the high pressure pump 36 to the annular groove extension 94 of the valve housing and via the control edges 96 and 98 of the housing or the stepped piston , depending on the amount of pressure oil flowing into the annular drive pressure chamber 22 of the drive cylinder 13.
  • the tool 11 is moved in rapid feed operation in the direction of the workpiece 12, this feed movement taking place in the drive pressure chambers 21 and 22 of the hydraulic cylinder 13 with only moderate pressure development.
  • the stepped piston thereby becomes further in the sense of lifting the valve ball 64 from its seat displaced, whereby the communicating connection of the central valve chamber 71 with the groove-shaped extension 94 which is still under the high outlet pressure of the pressure supply unit 23 is canceled.
  • the stepped piston moves into the “upper” end position shown in FIG. 3, in which the annular drive pressure chamber 22 is relieved via the central valve chamber 71 and the valve chamber 57, which is arranged “above” anyway, to the tank 34 of the pressure supply unit 23 .
  • the high output pressure of the pressure supply unit 23 is now only applied to the upper, larger drive pressure chamber 21 of the hydraulic cylinder 13, which now performs its working stroke with a lower feed rate but with a correspondingly increased force in the load feed operation.

Landscapes

  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Fluid-Pressure Circuits (AREA)
  • Press Drives And Press Lines (AREA)
  • Perforating, Stamping-Out Or Severing By Means Other Than Cutting (AREA)
  • Control Of Presses (AREA)

Abstract

Un dispositif hydraulique d'entraînement d'outils d'estampage ou de frappe comprend un cylindre hydraulique d'entraînement à double action avec des surfaces de piston de dimensions diverses qui permettent de régler, par leur application commune ou alternative de pression, l'avance rapide, l'avance de travail et le retrait rapide. A cet effet, une soupape de commutation des surfaces permet de passer du fonctionnement différentiel à l'application unilatérale de pression sur les plus grandes surfaces d'entraînement lorsque la pression d'entraînement dépasse par exemple 90 % de la pression maximale de sortie de l'aggrégat d'alimentation en pression. La soupape de commutation des surfaces comprend une soupape de non-retour sollicitée dans le sens d'ouverture par la pression de travail régnant dans la plus petite chambre de pression d'entraînement. L'élasticité de fermeture de la soupape de commutation des surfaces comprend une soupape à tiroir hydraulique dont le corps de soupape, qui a la forme d'un piston à gradins, est poussé par un ressort de rappel contre le corps de la soupape de non-retour. Lorsque la soupape de non-retour est formée, la pression s'applique sur la plus petite chambre de pression d'entraînement. Lorsque la soupape de non-retour est ouverte, la pression est détendue dans la plus petite chambre de pression d'entraînement et la pression qui règne dans la plus grande chambre de pression d'entraînement s'applique sur le grand gradin du piston à gradins. Le rapport entre les surfaces du plus grand gradin du piston et la superficie recouverte par le siège de la soupape de non-retour est supérieur au rapport entre la plus grande et la plus petite surface du piston du cylindre hydraulique.
EP88908928A 1987-10-16 1988-10-15 Dispositif hydraulique d'entrainement Expired - Lifetime EP0335939B1 (fr)

Priority Applications (1)

Application Number Priority Date Filing Date Title
AT88908928T ATE60113T1 (de) 1987-10-16 1988-10-15 Hydraulische antriebsvorrichtung.

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
DE19873735123 DE3735123A1 (de) 1987-10-16 1987-10-16 Hydraulische antriebsvorrichtung
DE3735123 1987-10-16

Publications (2)

Publication Number Publication Date
EP0335939A1 true EP0335939A1 (fr) 1989-10-11
EP0335939B1 EP0335939B1 (fr) 1991-01-16

Family

ID=6338497

Family Applications (1)

Application Number Title Priority Date Filing Date
EP88908928A Expired - Lifetime EP0335939B1 (fr) 1987-10-16 1988-10-15 Dispositif hydraulique d'entrainement

Country Status (5)

Country Link
US (1) US4958548A (fr)
EP (1) EP0335939B1 (fr)
JP (1) JP2581789B2 (fr)
DE (2) DE3735123A1 (fr)
WO (1) WO1989003484A1 (fr)

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EP0681672B2 (fr) * 1993-02-02 2000-09-20 PUTZMEISTER Aktiengesellschaft Procede permettant d'acheminer des matieres consistantes contenant des dechets metalliques prebroyes ou des solides analogues
DE4414779C1 (de) * 1994-04-25 1995-11-02 Mannesmann Ag Multifunktionsventil
DE19543876A1 (de) * 1995-11-24 1997-05-28 Rexroth Mannesmann Gmbh Verfahren und Vorrichtung zur Ansteuerung einer Hydroanlage eines Arbeitsgerätes
DE19623549A1 (de) * 1996-06-13 1997-12-18 I T E C Gmbh Steuerung von Bewegungen an Maschinen und Vorrichtungen
US7305914B2 (en) * 2004-01-28 2007-12-11 The United States Of America, As Represented By The Administrator Of The Environmental Protection Agency Hydraulic actuator control valve
DE102006029523B4 (de) * 2006-06-27 2014-10-23 Damcos A/S Stellvorrichtung
WO2010123987A1 (fr) * 2009-04-24 2010-10-28 Alcoa Inc. Soupape de surpression
USD711839S1 (en) * 2012-07-03 2014-08-26 Abb Ag Hydraulic drive for high-voltage circuit breaker
JP5971595B2 (ja) * 2013-04-10 2016-08-17 Smc株式会社 パンチ装置
ES2665767T3 (es) * 2015-07-06 2018-04-27 Feintool International Holding Ag Equipo y procedimiento para retirar/expulsar una retícula de estampado/pieza conformada interiormente y eyección de una pieza cortada en una prensa de corte de precisión
AT524160B1 (de) 2020-08-19 2022-06-15 Engel Austria Gmbh Hydraulische Antriebsvorrichtung für eine Formgebungsmaschine
US12304423B2 (en) * 2022-01-19 2025-05-20 Deere & Company Remote start system and method for a work machine
CN114738263B (zh) * 2022-04-16 2024-11-19 台州巨力工具股份有限公司 一种控油系统

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Also Published As

Publication number Publication date
JP2581789B2 (ja) 1997-02-12
JPH02501634A (ja) 1990-06-07
US4958548A (en) 1990-09-25
DE3861589D1 (de) 1991-02-21
DE3735123A1 (de) 1989-06-29
WO1989003484A1 (fr) 1989-04-20
EP0335939B1 (fr) 1991-01-16

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