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EP2401141A1 - Groupe hydraulique d'entraînement - Google Patents

Groupe hydraulique d'entraînement

Info

Publication number
EP2401141A1
EP2401141A1 EP10706597A EP10706597A EP2401141A1 EP 2401141 A1 EP2401141 A1 EP 2401141A1 EP 10706597 A EP10706597 A EP 10706597A EP 10706597 A EP10706597 A EP 10706597A EP 2401141 A1 EP2401141 A1 EP 2401141A1
Authority
EP
European Patent Office
Prior art keywords
control
piston
chamber
working
hydraulic drive
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.)
Withdrawn
Application number
EP10706597A
Other languages
German (de)
English (en)
Inventor
Werner Kuttruf
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.)
Voith Patent GmbH
Original Assignee
Voith Patent GmbH
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 Voith Patent GmbH filed Critical Voith Patent GmbH
Publication of EP2401141A1 publication Critical patent/EP2401141A1/fr
Withdrawn legal-status Critical Current

Links

Classifications

    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
    • F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
    • F15B9/00—Servomotors with follow-up action, e.g. obtained by feed-back control, i.e. in which the position of the actuated member conforms with that of the controlling member
    • F15B9/02—Servomotors with follow-up action, e.g. obtained by feed-back control, i.e. in which the position of the actuated member conforms with that of the controlling member with servomotors of the reciprocatable or oscillatable type
    • F15B9/08—Servomotors with follow-up action, e.g. obtained by feed-back control, i.e. in which the position of the actuated member conforms with that of the controlling member with servomotors of the reciprocatable or oscillatable type controlled by valves affecting the fluid feed or the fluid outlet of the servomotor
    • F15B9/12—Servomotors with follow-up action, e.g. obtained by feed-back control, i.e. in which the position of the actuated member conforms with that of the controlling member with servomotors of the reciprocatable or oscillatable type controlled by valves affecting the fluid feed or the fluid outlet of the servomotor in which both the controlling element and the servomotor control the same member influencing a fluid passage and are connected to that member by means of a differential gearing
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B30—PRESSES
    • B30B—PRESSES IN GENERAL
    • B30B1/00—Presses, using a press ram, characterised by the features of the drive therefor, pressure being transmitted directly, or through simple thrust or tension members only, to the press ram or platen
    • B30B1/32—Presses, using a press ram, characterised by the features of the drive therefor, pressure being transmitted directly, or through simple thrust or tension members only, to the press ram or platen by plungers under fluid pressure

Definitions

  • the invention relates to a hydraulic drive with a guided in a housing working piston.
  • Hydraulic drive devices are known in various designs. These usually have a hydraulic control circuit, with which the controlled variable (travel of the working piston) is set by the specification of a reference variable.
  • a hydraulic linear servo amplifier is described in EP 0 296 104 B1.
  • the movement of the piston is controlled by mechanical displacement of a spool by means of an actuating rod.
  • a controlled hydraulic feed drive is also known. The movement of the piston is controlled by an electrically controlled control valve, wherein the hydraulic control circuit is produced by a displacement measuring system on a pilot cylinder.
  • Such hydraulic drives come in particular as press and
  • the invention has for its object to provide a robust, simply constructed hydraulic drive with great flexibility in the arrangement of the components.
  • a hydraulic drive according to claim 1.
  • This comprises a working piston guided in a housing along a working direction, the working piston defining a working pressure space which can be filled with a pressure fluid for movement of the working piston in the working direction.
  • the working piston also limits a control chamber whose volume increases in movement of the working piston in the working direction.
  • a guided in a control cylinder control piston is provided, which is displaceable along a control axis between a neutral position, a supply of pressurized fluid into the working pressure space enabling inflow position and a drainage of pressurized fluid from the working pressure space enabling discharge position.
  • a piston chamber is provided, which is filled for movement of the control piston from the neutral position into the inflow position or from the outflow position to the neutral position with a control fluid, and is removed to move the control piston from the neutral position to the outflow control fluid.
  • the piston chamber is also pressure-connected to the control chamber such that the control piston is returned by the change in volume of the control chamber in the neutral position.
  • control piston thus takes place via the control fluid, whereas the movement of the working piston takes place by means of the pressurized fluid.
  • pressurized fluid and control fluid may be formed by different media and provided with widely different pressures.
  • the control fluid can be provided in an energy-saving manner from a low-pressure supply and the pressurized fluid as the actual working medium from a high-pressure supply.
  • the setpoint input thus takes place by the supply / discharge of control fluid in / out of the piston chamber interacting with the control piston. Since the piston chamber is pressure-connected to the control chamber, the supply / discharge of the control fluid can also be done in / from the control room.
  • the volume of control fluid represents the reference variable of the hydraulic control loop.
  • the controlled variable is the travel of the working piston.
  • a feedback of the controlled variable (travel) to the reference variable (control fluid volume) is carried out hydraulically via the associated with the piston movement change in the volume of the control chamber.
  • control piston is designed as a moving component in addition to the actual working piston.
  • the control cylinder may be stationary, in particular connected to the housing or integrated into this integrated.
  • the hydraulic drive therefore has a high fidelity and high response speed.
  • a reduction in the number of moving parts also simplifies the structure in that complex measures for sealing are required only in a few places.
  • malfunctions are largely avoided by tilting movable components against each other, as can occur, for example, in hydraulic linear actuators with mechanical control via spool.
  • the hydraulic drive according to the invention can therefore be operated with high reliability and robust against interference.
  • the structure of the hydraulic drive according to the invention can be flexibly adapted to the available space.
  • the control cylinder can be arranged parallel to the working piston.
  • the piston chamber is pressure-connected to the control chamber, which can be realized for example by rigid or flexible pressure lines.
  • Such freedom of design is not possible, for example, in mechanically controlled hydraulic linear drives on principle.
  • control piston can limit the piston chamber directly.
  • Equalizing piston is provided between the control piston and the piston chamber acting on the control piston Equalizing piston.
  • the desired transmission ratio of the working piston and the control piston can be specified, in particular, which can be brought in different positions control piston can be executed as a standard component.
  • Control space limiting hydraulic effective area of the working piston is equal to, smaller than or greater than the piston space limiting hydraulic effective area of the control piston or the intermediate balance piston.
  • a preferred embodiment of the invention results from the fact that the working piston has a working portion which limits the working pressure chamber and further comprises a working portion remote, designed as a guide piston area, softer limits the control room.
  • the working pressure chamber is thus spatially separated from the control room and not hydraulically pressure-connected.
  • the guide piston can be formed in particular by a guide rod, which is guided for axial alignment of the working piston in the housing and the end face is formed like a piston.
  • control piston and control cylinder can be arranged together with the working piston in the housing of the hydraulic drive.
  • control axis of the control piston and the working direction of the working piston preferably run parallel.
  • control axis extends at an angle to the working direction.
  • control piston parallel to
  • Guide piston is arranged in the housing and that the end face of the housing, the control chamber and the piston chamber of the control piston limited together.
  • the guide piston and the control piston thus have such similar axial dimensions that a common arrangement in the housing with a common cover is possible. Such a hydraulic drive is thus extremely compact and robust.
  • Control cylinder connected to pressure lines is arranged spaced from the housing.
  • the control axis can be arranged at any angle to the working direction. This allows a particularly flexible design of the hydraulic drive.
  • arrangements can be realized in which only very little space is required for the actual working unit (working piston and housing). All controls can be arranged separately from the work unit. Precise control is still possible.
  • control piston has control edges, which cooperate with control edges on the control cylinder for controlling the flow of pressurized fluid such that the flow through the deflection of the control piston from the neutral position along the control axis is continuously adjustable. Since the working piston is moved by filling the working pressure chamber with pressurized fluid, a proportional control of the speed of the piston movement is possible by the arrangement described. During operation of the device, therefore, the working piston can be moved at different speeds depending on the requirement.
  • a spring means which acts on the control piston resiliently against the pressure prevailing in the piston chamber pressure so that the control piston is held in the neutral position.
  • the spring means may be formed in particular as a hydraulic spring or as a helical spring.
  • control fluid supply provided such that a defined volume of control fluid can be fed into the piston chamber or discharged from the piston chamber.
  • the control fluid supply can be remote from the working piston or its housing and remote from the control piston or its cylinder.
  • the supply of control fluid in the piston or control chamber can be done via rigid or flexible pressure lines.
  • control fluid supply can be designed as an electrofluidic converter with a piston for outputting a defined volume of control fluid from a control fluid tank.
  • a transducer operates on the principle of an "infusion syringe.”
  • the volume dispensed may be calibrated once for a particular movement of the piston, allowing for precise control of the working piston.
  • control fluid supply includes a low-pressure pump or a low-pressure accumulator for control fluid and an electric directional control valve for controlling the supplied from the low-pressure pump and the low-pressure accumulator to the control chamber volume of control fluid.
  • a directional control valve for example, a continuous servo valve can be used.
  • control fluid supply comprises a motor driven by a pump over which a predetermined volume in or out of the piston chamber is supplied or removed. It is also grateful that the control fluid supply comprises a motor-driven eccentric piston, via which a predeterminable volume can be supplied to or removed from the piston chamber.
  • a measuring device for determining the volume of the supplied into the control chamber or discharged from the control chamber control fluid is provided.
  • the measured volume values can be used, for example, to set up the hydraulic feedback or to increase the precision of the control. It is also conceivable, a measuring device for determining the
  • the pressure of the control fluid is lower than the pressure of the pressurized fluid during operation of the device.
  • the movement of the control piston can therefore be done with little energy and effort.
  • the hydraulic drive acts as a hydraulic booster in this sense.
  • the pressure fluid and the control fluid is formed by a hydraulic oil, wherein for the provision of pressurized fluid, a high-pressure supply and to provide control fluid, a low pressure supply for hydraulic oil can be provided.
  • the control of the hydraulic drive thus takes place by providing defined volumes of hydraulic oil at low pressure and is associated with only a small amount of energy.
  • FIG. 1 shows a longitudinal section through an inventive device
  • Figure 2 is a sketched further embodiment of the control fluid supply in cooperation with a volume measuring device
  • FIG. 3 shows a sketched further embodiment of the control fluid supply
  • FIG. 4 shows a sketched further embodiment of the control fluid supply.
  • the inventive hydraulic drive 1 shown in Figure 1 has a working piston 2 with a working section 3, which is sealingly guided in a housing 5 along a working direction 7.
  • the working piston 2 comprises a piston rod 9 designed to extend in the working direction 7.
  • the region of the working piston 2 facing away from the working direction 7 against the working portion 3 is designed as a guide piston 11.
  • the diameter 15 of the guide piston 11 is smaller than the diameter 13 of the working portion 3.
  • the guide piston 11 is sealingly guided in the guide portion 6 of the housing 5.
  • the working piston 2 limits with its working section 3 a
  • Working pressure chamber 17 On the working pressure chamber 17 side facing away from an annular space 4 is present, in which there is preferably a continuous pressure.
  • the work piston 3 delimiting the working pressure chamber 17 has a hydraulic active surface 14 for moving the working piston 2.
  • the control piston 11 delimiting the control chamber has a hydraulic active surface 16.
  • a high-pressure supply 21 is provided to supply the working pressure chamber 17 with a pressurized fluid, which is formed here by a hydraulic oil.
  • a tank 23 is provided to receive from the working pressure chamber 17 effluent hydraulic oil.
  • a control cylinder 25 is further arranged, in which a control piston 27 is guided sealingly displaceable along a control axis 29.
  • the control axis 29 runs parallel to the working direction 7.
  • the working direction 7 and the control axis 29 can enclose an arbitrary angle.
  • the guide portion 6 of the housing 5, the guide piston 11, the control cylinder 25 and the control piston 27 have similar axial dimensions and are arranged in the housing 5 parallel to each other.
  • the end face 31 of the housing 5 forms a common conclusion of the guide portion 6 and the control cylinder 25.
  • the control piston 27 On the side facing away from the working section 3 of the control piston 27 is provided by the control piston 27 preferably separately trained, the control piston 27 fitting, balancing piston 37 is provided.
  • the control piston 27 has two annular collar-like axial extensions 39, 41.
  • the extension 39 acts against the balance piston 37, which limits a piston chamber 33 with the control cylinder 25. Between the two extensions 39, 41 is a flow space 35.
  • the control piston 27 facing away from end face 52 of the balance piston 37 forms a hydraulic active surface 53 for movement of the balance piston 37 and the control piston 27th
  • the desired gear ratio of the control piston 27 and the guide piston 11 can be given without having to change the size ratios of the guide piston 11 and control piston 27.
  • the balance piston 37 can also be omitted.
  • the flow space 35 is connected via a pressure channel 45 with the
  • control cylinder 25 In the control cylinder 25 are through annular recesses a
  • the inlet chamber 49 is connected to the high pressure supply 21, the return chamber 51 to the tank 23rd
  • the annular collar-like extension 41 of the control piston 27 has a
  • Control edge 60 which cooperates with a control edge 62 of the inlet chamber 49.
  • a control edge 64 is provided on the annular collar-like extension 39 for cooperation with a control edge 66 on the control piston 27.
  • control edges 60 and 62 or 64 and 66 are aligned with each other.
  • the flow space 35 is thus neither in the neutral position with the inflow chamber 49 still connected to the return chamber 51 pressure-connected. If the control piston 27 is moved downwards from its position shown in FIG. 1, it enters the inflow position. In this case, a gap between the corresponding control edges 60 and 62 opens, whereby the inlet chamber 49 is pressure-connected to the flow space 35. If, on the other hand, the control piston 27 is moved upwards from its neutral position in FIG. 1, the return flow chamber 51 is pressure-connected to the flow space 35 in an analogous manner by opening a gap between the control edges 64 and 66. In this situation, the control piston 27 is in its drainage position.
  • control piston 27 has a bottom side 54, on which a arranged between the housing 5 and the control piston 27 spring means 55, which is designed here as a helical spring 56 is supported.
  • the control piston 27 is thereby acted upon by a force up against the pressure prevailing in the piston chamber 33 pressure.
  • a control fluid supply 80 is provided in order to supply the piston chamber 33 or the control chamber 19 with a defined volume of control fluid.
  • the control fluid supply 80 is formed in FIG. 1 as an electrofluidic converter 81.
  • a control fluid space 87 is provided which is delimited by a piston 83.
  • the piston 83 is driven by a linear electric motor 89.
  • a defined volume of control fluid is squeezed out of the control fluid chamber 87 and supplied to the piston chamber 33.
  • the electrofluidic transducer 81 operates similarly to an infusion syringe.
  • the piston chamber 33 is supplied by the control fluid supply 80, a defined volume of control fluid.
  • the supply of control fluid increases the pressure on the active hydraulic surface 53 of the balance piston 37 and thus on the control piston 27. This then differs from its neutral position in the direction of the inflow position down ,
  • the control fluid supply 80 only has to overcome the counterforce of the spring means 55 and can therefore be designed as an energy-saving low-pressure supply.
  • In the inflow position of the control piston 27 opens a gap between the inlet chamber 49 and the flow space 35 as described above.
  • pressurized fluid flows from the high pressure supply 21 through the inlet chamber 49, through the flow space 35, via the pressure channel 45 and into the working pressure chamber 17th the working piston 2 is moved from its initial position in the working direction 7.
  • the movement path of the working piston 2 along the working direction 7 is just so great that the movement associated with the increase in the volume of the control chamber 19 just corresponds to the volume supplied to the control fluid .
  • the increase in volume of the control chamber 19 compensates the volume supplied to the piston chamber 33. By this volume compensation leaves the force acting on the hydraulic active surface 53 of the balance piston 37 force, and the control piston 27 returns due to the upward force of the spring means 55 back to its neutral position.
  • the opening width of the gap between the corresponding control edges 60, 62 and 64, 66 is continuously adjustable. Since the opening width of the gaps between inlet chamber 49 and return chamber 51 and the flow space 35 regulates the time flow rate of control fluid, a proportional control of the travel speed of the working piston is possible in this way.
  • the hydraulic over- or reduction between the volume of control fluid and the volume of pressurized fluid is determined by the ratio of the active hydraulic surface 16 in the control chamber 19 and the hydraulic active surface 14 of the working piston 2 in the working pressure chamber 17.
  • the device works insofar as a hydraulic booster on the one hand, on the other hand as a hydraulic ratio.
  • Measuring device 75 for determining the supplied from the control fluid supply 80 in the piston chamber 33 and discharged from the piston chamber 33 volume of control fluid. Furthermore, a control unit 76 is provided, which controls the linear motor 89, evaluates distance measuring signals of the deflection of the linear motor 89 and the output volume measured by the measuring device 75.
  • the measuring device 75 can be omitted.
  • Hydraulic drive can be done in different ways.
  • a control fluid supply 90 is sketched in Figure 2, which cooperates with a measuring device 75 for the added or removed volume of control fluid and a control unit 76 .
  • the control fluid supply 90 comprises a low-pressure supply or low-pressure source 92 for hydraulic oil, which forms the control fluid here.
  • the flow of hydraulic oil from the low-pressure supply 92 to the piston chamber 33 (see Fig. 1) is controlled by an electrically operable directional control valve 96, which is controlled by the control unit 76 accordingly.
  • a defined volume of control fluid can be provided by the measuring device 75 measuring the volume of control fluid supplied or removed, and the control unit 76 correspondingly activating the directional control valve 96 by comparing the measured values with the defined specifications.
  • the control fluid supply 100 sketched in FIG. 3 has a reservoir 102 for control fluid and a pump 106.
  • the pump 106 is driven by a motor 105.
  • the motor 105 is actuated by an electrical control unit 76 so that a defined volume of control fluid can be made available to the piston chamber 33 (see FIG. 1) or the control chamber 19 (see FIG. Via a measuring system 104, the speed and thus the delivery volume of the pump 106 can be determined.
  • FIG. 4 shows a further control fluid supply 110.
  • This comprises an eccentric 114 driven by a motor 112, via which a piston 116 is moved up and down. Via the piston 116, a predeterminable volume is fed into the connecting line 108 or removed from the connecting line 108.
  • a volume compensation 118 in particular for adjusting the initial position of the working piston 2, can be connected to the connecting line 108.
  • Such a control fluid supply 110 finds particular use in comparatively fast, periodically recurring strokes of the working piston 2.

Landscapes

  • Engineering & Computer Science (AREA)
  • Physics & Mathematics (AREA)
  • Fluid Mechanics (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Fluid-Pressure Circuits (AREA)

Abstract

L'invention concerne un groupe hydraulique d'entraînement (1) comprenant un piston de travail (2) guidé dans un carter (5) dans une direction de travail (7). Le piston de travail (2) délimite une chambre de pression de travail (17) qui peut être remplie d'un fluide sous pression afin de déplacer le piston de travail (2) dans la direction de travail (7) et délimite en outre une chambre de commande (19) dont le volume augmente lors du mouvement du piston de travail (2) dans la direction de travail (7). Le groupe comprend en outre un piston de commande (27) guidé dans un cylindre de commande (25), qui peut coulisser le long d'un axe de commande (29) entre une position neutre, une position d'admission permettant l'admission de fluide sous pression dans la chambre de pression de travail et une position d'évacuation permettant l'évacuation du fluide sous pression par la chambre de pression de travail (17). Le piston de commande délimite une chambre de piston (33) qui est remplie d'un fluide de commande afin de déplacer le piston de commande (27) entre la position neutre et la position d'admission ou entre la position d'évacuation et la position neutre et qui est reliée sous pression avec la chambre de commande (19) de manière que la variation du volume de la chambre de commande (19) ramène le piston de commande (27) dans la position neutre.
EP10706597A 2009-02-25 2010-02-24 Groupe hydraulique d'entraînement Withdrawn EP2401141A1 (fr)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
DE200910011441 DE102009011441B4 (de) 2009-02-25 2009-02-25 Hydraulikantrieb
PCT/EP2010/052316 WO2010097399A1 (fr) 2009-02-25 2010-02-24 Groupe hydraulique d'entraînement

Publications (1)

Publication Number Publication Date
EP2401141A1 true EP2401141A1 (fr) 2012-01-04

Family

ID=42194690

Family Applications (1)

Application Number Title Priority Date Filing Date
EP10706597A Withdrawn EP2401141A1 (fr) 2009-02-25 2010-02-24 Groupe hydraulique d'entraînement

Country Status (3)

Country Link
EP (1) EP2401141A1 (fr)
DE (1) DE102009011441B4 (fr)
WO (1) WO2010097399A1 (fr)

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE102010037330B4 (de) * 2010-09-06 2013-07-11 Schuler Pressen Gmbh & Co. Kg Antriebseinrichtung mit Linearmotor für eine Presse

Family Cites Families (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4907492A (en) * 1987-06-16 1990-03-13 Sig Schweizerische Industrie-Gesellschaft Apertured valve disposed in hollow piston rod of follower-type motor
DE4227563C2 (de) * 1992-08-20 2000-04-13 Mannesmann Rexroth Ag Geregelter hydraulischer Vorschubantrieb
DE102004034280A1 (de) * 2004-07-15 2006-02-23 Schema-Hydraulik Gmbh Selbststeuer-Eilgangzylinder
DE102006041707B4 (de) * 2006-05-10 2009-01-02 Tünkers Maschinenbau Gmbh Kolben-Zylinder-Einheit (Arbeitszylinder) zum Spannen, und/oder Pressen, und/oder Fügen, und/oder Stanzen, und/oder Prägen, und/oder Lochen und/oder Schweißen, zum Beispiel unter Zwischenschaltung einer Kniehebelgelenkanordnung

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
See references of WO2010097399A1 *

Also Published As

Publication number Publication date
WO2010097399A1 (fr) 2010-09-02
DE102009011441A1 (de) 2010-09-02
DE102009011441B4 (de) 2012-11-29

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