WO2009097703A1 - Soupape proportionnelle à dynamique élevée - Google Patents

Soupape proportionnelle à dynamique élevée Download PDF

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Publication number
WO2009097703A1
WO2009097703A1 PCT/CH2009/000037 CH2009000037W WO2009097703A1 WO 2009097703 A1 WO2009097703 A1 WO 2009097703A1 CH 2009000037 W CH2009000037 W CH 2009000037W WO 2009097703 A1 WO2009097703 A1 WO 2009097703A1
Authority
WO
WIPO (PCT)
Prior art keywords
valve
proportional valve
control
drive shaft
dynamic proportional
Prior art date
Application number
PCT/CH2009/000037
Other languages
German (de)
English (en)
Inventor
Ronald Siegrist
Hugo Blöchlinger
Stephan Schwarz
Thomas Bloos
Original Assignee
Moog Procontrol Ag
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Moog Procontrol Ag filed Critical Moog Procontrol Ag
Publication of WO2009097703A1 publication Critical patent/WO2009097703A1/fr

Links

Classifications

    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
    • F16K—VALVES; TAPS; COCKS; ACTUATING-FLOATS; DEVICES FOR VENTING OR AERATING
    • F16K31/00—Actuating devices; Operating means; Releasing devices
    • F16K31/02—Actuating devices; Operating means; Releasing devices electric; magnetic
    • F16K31/04—Actuating devices; Operating means; Releasing devices electric; magnetic using a motor
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
    • F16K—VALVES; TAPS; COCKS; ACTUATING-FLOATS; DEVICES FOR VENTING OR AERATING
    • F16K11/00—Multiple-way valves, e.g. mixing valves; Pipe fittings incorporating such valves
    • F16K11/02—Multiple-way valves, e.g. mixing valves; Pipe fittings incorporating such valves with all movable sealing faces moving as one unit
    • F16K11/06—Multiple-way valves, e.g. mixing valves; Pipe fittings incorporating such valves with all movable sealing faces moving as one unit comprising only sliding valves, i.e. sliding closure elements
    • F16K11/065—Multiple-way valves, e.g. mixing valves; Pipe fittings incorporating such valves with all movable sealing faces moving as one unit comprising only sliding valves, i.e. sliding closure elements with linearly sliding closure members
    • F16K11/07—Multiple-way valves, e.g. mixing valves; Pipe fittings incorporating such valves with all movable sealing faces moving as one unit comprising only sliding valves, i.e. sliding closure elements with linearly sliding closure members with cylindrical slides

Definitions

  • Proportional valves are sometimes referred to as servo valves. They belong to the continuous valves and are used in hydraulics especially where variable or continuously adjustable volume flows are required. Small volume flows can be controlled conventionally, for example by means of directly operated valves up to nominal size 6. For controlling large volume flows, on the other hand, which are in the order of about 200 l / min to about 600 l / min, or for valves with nominal sizes NG 10 (according to ISO4401-05-05-0-05) or NG 16 (according to ISO4401 -07-07-0-05) and larger, conventionally hydraulically pilot operated two- to three-stage valves are used.
  • the dynamics of the fastest proportional valves available today with nozzle flapper pilot valve and a nominal flow rate of 400 l / min can be characterized by the following specifications: With a piston stroke (amplitude) of approx. +/- 90%, a phase shift of -45 degrees and (in terms of absolute value) must be expected even at operating frequencies from 60 Hz to 70 Hz. In such valves, the pressure build-up or force build-up for adjusting the main piston is dependent on the dynamics of the pilot valve.
  • the fastest known pilot valves have response times of 2ms to 4ms, resulting in a correspondingly delayed pressure build-up on the main piston. For large piston strokes, large volume flows are required in the pilot circuit. Effects such as volumetric flow saturation can have a negative effect. Certain applications such as active damping of vibrations of mechanical machine structures, fast
  • the phase shift should be as small as possible in terms of amount. It should be less than -45 degrees at operating frequencies up to 150 Hz and at high signal amplitude or a piston stroke of +/- 90% and at flow rates from about 200 l / min to about 600 l / min. As die casting machines inject liquid metal into molds, extremely large volume flows of more than 1000 l / min and short casting times in the order of magnitude of about 10 ms to 40 ms are required in order to prevent the metal from cooling during the process
  • an extremely fast proportional valve with the aforementioned properties can be used as a pilot valve for a large 2-way cartridge main stage up to nominal size 100.
  • the inventive highly dynamic proportional valve has a nominal size equal to or greater than NG 10 and is driven directly by a servo motor.
  • the force or torque build-up takes place in a brushless electric servomotor due to the current in the motor windings.
  • the current build-up can be done very quickly, namely in much less than lms, typically in 50 to 400 microseconds. This is thus about an order of magnitude faster than the time required for a conventional hydraulic pilot valve to achieve the maximum acceleration.
  • the maximum speed is correspondingly faster in the valve according to the invention.
  • the transmission of movement from the servomotor to the working piston is effected by a crank mechanism, wherein only a pivoting movement by a few angular degrees or by a maximum of +/- 15 degrees is required to deflect the working piston with maximum amplitude in both directions from the rest position.
  • the swivel range is chosen in the range of the largest transmission ratio or the highest speed transmission from the crank to the working piston. Compared to a transmission spindle, where for the same stroke of the
  • crank is preferably articulated with a fork to the piston, so that a rotational movement of the working piston prevents and the translation function can be kept constant.
  • Other features contribute significantly to the dynamics and the rapid controllability and controllability of the inventive proportional valve in:
  • a compact eccentric mechanism or crank mechanism is preferably used for converting the rotational movement of the servomotor into a linear movement.
  • the complete drive train including control piston is of low mass and stiff and has a natural frequency of preferably more than 500 Hz. In particularly optimized constructions, the natural frequency can also be IkHz or more.
  • the combination of high drive rigidity and low mass is constructively achieved by the shortest possible drive shaft (motor shaft with integrated eccentric shaft), wherein the motor shaft is formed as a hollow cylinder with pressed bearing journal.
  • To further reduce the moving masses of the control piston is hollow drilled, which also serves the hydrostatic compensation of the control piston.
  • the drive shaft may also be formed with a larger diameter than in conventional solutions or corresponding standard values.
  • the eccentric can be formed clutch-free directly on the motor shaft.
  • a clearance compensation can be provided by means of prestressed springs.
  • a hydraulic control a preferably hydrostatically balanced, linearly movable Control piston or alternatively a rotating control piston or a plate rotary valve can be used.
  • the control piston may be formed with a flow force compensation.
  • Non-linearities of the mechanics can be electronically compensated. Basically, any
  • Characteristics can be set or specified.
  • Connection with an optimized fast controller whose cutoff frequency is in the range of about 1.6 kHz, can be a
  • Duty cycle can be increased.
  • FIG. 1 shows a preferred embodiment of the proportional valve according to the invention
  • FIG. 2 shows a longitudinal section of the mechanical part of the proportional valve from FIG. 1 along the motor axis
  • Figure 4 shows a longitudinal section of an eccentric or
  • Figure 5 shows the proportional valve of Figure 4 in a first deflection position of the eccentric or
  • Figure 6 shows the proportional valve of Figure 4 in a second deflection position of the eccentric or
  • Figure 7 shows an arrangement for injection control in an injection molding machine
  • FIG. 9 shows an arrangement for damping vibrations in mechanical structures
  • Figure 10 is a schematic diagram of a nested
  • FIG. 1 shows an example of a proportional valve 1, wherein the mechanical part is shown in perspective.
  • the proportional valve 1 comprises a valve 3 in an approximately cuboid valve housing 4 with a standardized connection area (with ISO hole pattern), wherein the valve 3 has a nominal size which is greater than NG 6, a servomotor 5 in an approximately cuboid
  • valve housing. 4 and the motor housing 6 are frontally adjacent to adjacent sides of the Kochtriebsgephaseuses 8 and are flanged there or firmly screwed or connected in any other way. Because of the standardized connection surface, the valves 3 are easily replaceable.
  • the servomotor 5 is a rotating AC servomotor with a drive shaft 11 which is rotatable about a motor axis A1 and which projects beyond the motor housing 6 at the end and is preferably mounted in the overdrive housing 8 in axially spaced rotary bearings 10.
  • Figure 2 shows a longitudinal section of the mechanical part of the proportional valve 1 of Figure 1 along the motor axis Al.
  • the diameter of the drive shaft 11 is preferably larger than in standard conventional servomotors, for example, 19mm instead of 11mm, and the length of outstanding from the motor housing 6 drive shaft stub is relatively short. This contributes to that the drive shaft 11 is stiff and torsionally.
  • An eccentric or crank mechanism 13 for transmitting the movement is preferably connected between two rotary bearings 10 at a short distance from the motor housing 6 rigidly and without a clutch to the drive shaft 11 or formed directly on this.
  • the valve 3 comprises a control means 9 mounted in the valve housing 4 and along a piston axis A2 displaceable control piston 9a. Details of this are shown in the longitudinal section of FIG. 3, which is shown enlarged in FIG.
  • the piston axis A2 is aligned orthogonal to the drive or motor axis Al.
  • the control piston 9a comprises a front end in the direction of the piston axis A2 through a corresponding opening in the valve housing 4 on this projecting force transmission means 15 or is rigidly or hingedly connected to such a power transmission means 15.
  • the power transmission means 15 comprises an elongated shaft 17 and a head 19 with a claw, fork or gripper-like receptacle 21 in the example shown for a transmission element 14 of the eccentric or crank mechanism 13.
  • the eccentricity or the crank radius sl is corresponding to the required adjustment for the control piston 9a small and is of the order of about 10mm to about 30mm, for example 15mm.
  • the eccentric or crank mechanism 13 or its transmission element 14 or crank pin is mounted as free of play in the receptacle 21 of the power transmission means 15.
  • Figures 4, 5 and 6 each show a longitudinal section of the proportional valve 1 along the piston axis A2 with a view in the direction of the motor axis Al.
  • the control piston 9a in a rest position or center position. In this position, the transmission element 14 of the eccentric or crank mechanism 13 or the crank pin has no offset s2 with respect to the piston axis A2.
  • a pivoting angle ⁇ of the drive shaft 11 and thus also of the eccentric or crank drive 13 can be defined with respect to a reference virtual axis A3, which is both the
  • Motor axis Al and the piston axis A2 intersects and orthogonal to these axes Al, A2 is aligned.
  • the swivel angle ⁇ is equal to zero. In this position, the speed transmission from the eccentric or crank mechanism 13 to the control piston 9a is maximum.
  • control piston 9a be biased on both sides by springs within the valve housing 4 (not shown), wherein the restoring forces of these springs in the rest position or middle or neutral position of the control piston 9a with opposite effective direction are equal.
  • Swing angle ⁇ of eg maximum 13 ° or 15 ° along the Piston axis A2 are moved to a first end position.
  • Swing angle ⁇ of eg maximum 13 ° or 15 ° along the Piston axis A2 are moved to a first end position.
  • the stroke of the control piston 9a between the two end positions is 6.6 mm in the present example.
  • the parameters given here can also be optimized for valves 3 with different values for the closing path.
  • the valve 3 may be formed differently in terms of number and arrangement of the connections and with regard to the connection possibilities of these connections at defined intermediate positions of the control means 9 and the control piston 9a.
  • the valve 3 is a 4/3-way valve with a locking center position.
  • the required for moving the control piston 9a between the two end positions swivel range of the drive shaft 11 is limited to small pivot angle ⁇ within +/- 15 °.
  • a hydrostatic compensation and / or a flow force compensation for the control piston 9 a are provided, as these are known from the prior art.
  • an (not shown) alternative embodiment of the inventive highly dynamic proportional valve 1 at the front end of the power transmission means 15 is disposed 21 is a roller or a ball instead of a head 19 with a 'recording.
  • control piston 9a is loaded from the opposite side by means of a spring, so that the power transmission means 15 rests with the ball or roller without play on the eccentric or crank mechanism 13.
  • connection between the control piston 9a and the power transmission means 15 may also be articulated and include, for example, a septpleuel (not shown).
  • the control means 9 may for example also comprise a rotary control piston 9a or a plate rotary valve (not shown). In this case, the control means 9 can be moved by a rotation of, for example, a maximum of 180 ° or preferably less than 90 ° between the end positions.
  • a linear motor could also be used as the direct drive for the control piston 9a (no illustration).
  • a direct electrical drive acting on a control means 9 of a valve 3 ensures that the (mechanical) natural frequency of this drive system is higher than 500 Hz.
  • control-related features also contribute to the fact that the highly dynamic properties (possibility of executing very fast, short movements) of the proportional valve 1 can be optimally utilized.
  • the servo motor 5 is connected to an electronic control unit 31, said control electronics 31 comprises a so-called servo drive or short drive 33 for three-phase control of the servomotor 5 and a process controller 35.
  • the control electronics 31 is connected to a main power supply (3 x 400V) and optionally with a small signal supply (not shown).
  • the communication between the process controller 35 and the drive 33 used as valve controller conventionally usually takes place via a field bus with relatively long delay times of about 0.5ms to 2ms, in the inventive highly dynamic proportional valve 1 for this purpose, a fast communication connection (eg an X-bus similar Processor bus). There, the delay times are of the order of only 0.001ms.
  • the process controller 35 and the valve controller or drive 33 are spatially close to each other (eg in a common housing).
  • the process controller 35 may also be integrated with the valve controller 33 to minimize timing transmission and converter losses.
  • the control electronics has a cycle time of preferably a maximum of lms.
  • the control electronics of the external process and position control loop has a cycle time of less than 0.25 ms, preferably eg 0.1 ms.
  • the outer position control loop is preferably designed as a time-optimal controller, which takes into account the finite acceleration of the piston and the current or the current increase.
  • the process controller 35 is advantageously designed as a highly dynamic state controller for current, speed and angle of rotation or position.
  • the individual controller clocks are synchronized with each other so that no unnecessary delays and / or jitter occur.
  • the period of the longest of these control clocks determines the dynamics of the controller. It is preferably smaller than lms.
  • the control electronics 31 comprises input interfaces for coupling or returning measured quantities. These include, in particular, the signals of a resolver or rotary encoder of the servomotor 5 and the sensor signals required by the process controller 35 (eg, current, rotational speed, rotational angle).
  • the control electronics 31 processes the measured quantities in accordance with prescribed processing instructions.
  • processing instructions there For example, non-linearities of the eccentric or crank mechanism or the effect of line impedances or other undesirable properties can be detected and compensated or compensated, for example, by appropriate control characteristics.
  • a resolver or rotary encoder having a high resolution of e.g. +/- 2500 increments based on the total piston travel used.
  • a high resolution is also advantageous for the other measured quantities recorded.
  • Figure 7 shows schematically an injection control in a plastic injection molding machine with the inventive proportional valve 1. From a funnel-shaped container 51 passes
  • Plastic granules in a screw cylinder 53 where it is plasticized by means of a screw 57 driven by a worm motor 55.
  • the screw 57 by means of a controlled hydraulic drive (this includes one or more injection cylinder 63, each with a working piston 65 and a piston rod 67) axially postponed.
  • a controlled hydraulic drive this includes one or more injection cylinder 63, each with a working piston 65 and a piston rod 67
  • the injection cylinder or cylinders 63 are therefore driven by a highly dynamic proportional valve 1 according to the present invention.
  • the process controller 33 for the injection movement can be given as guide variables, for example, the pressure Psoii, with which the working piston 65 acts on the worm 57 via the piston rod 67, and the (feed) speed v so n of the worm 57.
  • the process controller 33 can be supplied eg with signals from a displacement transducer at the injection cylinder 63 and two pressure sensors at the ports A and B of the valve 3 (for determining the resulting pressure or the force acting on the working piston 65).
  • an adjustable hydraulic pump 69 hydraulic fluid is supplied to the valve port P from a container 71 under pressure. Via the valve connection T, hydraulic fluid can flow out to the container 71.
  • Figure 8 shows schematically and simplified casting control in a die casting machine.
  • liquid metal is conveyed by means of a metering in the casting channel 73 and from there by means of a casting piston 75 which is arranged on the piston rod 67 of the working piston 65, in the mold 59 injected.
  • the casting times must be very short (usually about 0.01s to about 0.04s), so that a cooling or even solidification of the liquid metal during the casting process can be prevented.
  • the hydraulic pressure of a hydraulic accumulator 77 is used, which acts on the back of the working piston 65.
  • the Giessregelung is piston rod side by a proportional valve 1, which comprises a valve 2 as a 2/2-way valve, which acts as a check valve in one end position and opens the passage between the two terminals in the other end position.
  • the inventive highly dynamic proportional valve 1 can be used as a pilot valve for a large 2-way cartridge main stage up to nominal size 100.
  • the process controller 33 can be specified as a reference variable, for example, the feed rate v so n for the injection movement. As measured variables, the
  • Process controller 33 e.g. Signals of a transducer on the casting cylinder 73 and signals from pressure sensors are supplied to the terminals of the injection cylinder.
  • the highly dynamic proportional valve 1 for the active damping of vibrations a mechanical structure, for example, the mast 81 of a high-bay forklift used.
  • the vibrations of the up to 12m high mast 81 are shown symbolically by a double arrow 83.
  • Such unwanted vibrations or natural oscillations can be excited during driving, for example, by changes in the speed and / or the direction of travel.
  • Such vibrations can be actively damped by means of an extremely fast proportional valve 1.
  • the valve 3 must be about 3 to 5 times faster than the natural frequency of the mechanical structure.
  • a highly dynamic proportional valve 1 with a large signal frequency of about 120 to about 200 Hz is needed.
  • the mast 81 is fixed at a maximum of 45 ° phase shift on a pivotally mounted stage 85, wherein the pivot angle is controlled by the hydraulic drive with the rapid proportional valve 1.
  • acceleration and / or displacement sensors on the damping cylinder and pressure sensors in the cylinder ports can be used as sensors which provide the measured quantities for the regulator.
  • FIG. 10 shows to complete a schematic diagram of a nested regulator 89 with a preferably time-optimal position controller 92 and a synchronous thereto Process controller 91. These are connected via an X-bus or a fast (processor) bus connection 101 with a commutation, current and torque controller 93 and a speed and / or speed controller 94.
  • Reference numeral 95 denotes an alternative arrangement of the position controller 92.
  • the controller 89 acts on a highly dynamic motor 96 with position measurement and mechanical connection to the valve 7.
  • the valve 7 preferably has a special hydraulic supply 8 (P / T supply with miniature memory built-in).
  • the reference numeral 99 designates a machine or a process which supplies the process variables 100 to the controller 89 on the input side.

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  • Engineering & Computer Science (AREA)
  • General Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Electrically Driven Valve-Operating Means (AREA)

Abstract

La présente invention concerne une soupape proportionnelle à dynamique élevée (1) destinée à commander ou réguler rapidement des débits volumiques importants et comprenant une soupape (3), qui est réglée par un entraînement électrique direct et présente une grandeur nominale supérieure à la grandeur nominale 6. Dans une configuration préférée, un servomoteur CA (5) agit sur un piston de commande (9a) de la soupape (3), lequel piston étant axialement mobile par l'intermédiaire de moyens de transmission compacts et rigides. La valve proportionnelle (1) comprend une commande (31) comportant des régleurs d'état rapides et permet des fréquences de signaux forts supérieures à 100 Hz pour un décalage de phase inférieur à -45 degrés.
PCT/CH2009/000037 2008-02-04 2009-02-02 Soupape proportionnelle à dynamique élevée WO2009097703A1 (fr)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
CH1542008 2008-02-04
CH154/08 2008-02-04

Publications (1)

Publication Number Publication Date
WO2009097703A1 true WO2009097703A1 (fr) 2009-08-13

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PCT/CH2009/000037 WO2009097703A1 (fr) 2008-02-04 2009-02-02 Soupape proportionnelle à dynamique élevée

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Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE102013001148A1 (de) 2013-01-24 2014-07-24 Voith Patent Gmbh Kolbenschieberventil
CN113107918A (zh) * 2021-04-22 2021-07-13 浙江工业大学 基于间隙补偿位移放大联轴节的二维半桥电液比例换向阀

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5263681A (en) * 1992-11-23 1993-11-23 Hr Textron, Inc. Motor-to-spool coupling for rotary-to-linear direct drive valve
US5508575A (en) * 1994-01-27 1996-04-16 Hr Textron Inc. Direct drive servovalve having magnetically loaded bearing
WO2001096749A2 (fr) * 2000-06-13 2001-12-20 Hr Textron, Inc. Mecanisme de commande de soupape a bille a entrainement direct et son procede de production
US20070069592A1 (en) * 2005-09-23 2007-03-29 Spickard Mark A Stepper motor driven proportional actuator

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5263681A (en) * 1992-11-23 1993-11-23 Hr Textron, Inc. Motor-to-spool coupling for rotary-to-linear direct drive valve
US5508575A (en) * 1994-01-27 1996-04-16 Hr Textron Inc. Direct drive servovalve having magnetically loaded bearing
WO2001096749A2 (fr) * 2000-06-13 2001-12-20 Hr Textron, Inc. Mecanisme de commande de soupape a bille a entrainement direct et son procede de production
US20070069592A1 (en) * 2005-09-23 2007-03-29 Spickard Mark A Stepper motor driven proportional actuator

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE102013001148A1 (de) 2013-01-24 2014-07-24 Voith Patent Gmbh Kolbenschieberventil
WO2014114521A1 (fr) 2013-01-24 2014-07-31 Voith Patent Gmbh Distributeur à tiroir cylindrique
US9890863B2 (en) 2013-01-24 2018-02-13 Voith Gmbh Piston slide valve
CN113107918A (zh) * 2021-04-22 2021-07-13 浙江工业大学 基于间隙补偿位移放大联轴节的二维半桥电液比例换向阀

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