EP0577628A1 - Element actionneur mecano-electronique proportionnel. - Google Patents

Element actionneur mecano-electronique proportionnel.

Info

Publication number
EP0577628A1
EP0577628A1 EP92906082A EP92906082A EP0577628A1 EP 0577628 A1 EP0577628 A1 EP 0577628A1 EP 92906082 A EP92906082 A EP 92906082A EP 92906082 A EP92906082 A EP 92906082A EP 0577628 A1 EP0577628 A1 EP 0577628A1
Authority
EP
European Patent Office
Prior art keywords
positioner
pilot control
actuator
spindle
actuator means
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
EP92906082A
Other languages
German (de)
English (en)
Other versions
EP0577628B1 (fr
Inventor
Ilkka Ahonoja
Markku Luomaranta
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.)
NESTEPAINE Oy AB
Original Assignee
NESTEPAINE Oy AB
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 NESTEPAINE Oy AB filed Critical NESTEPAINE Oy AB
Publication of EP0577628A1 publication Critical patent/EP0577628A1/fr
Application granted granted Critical
Publication of EP0577628B1 publication Critical patent/EP0577628B1/fr
Anticipated expiration legal-status Critical
Expired - Lifetime 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
    • F15B15/00—Fluid-actuated devices for displacing a member from one position to another; Gearing associated therewith
    • F15B15/20—Other details, e.g. assembly with regulating devices
    • F15B15/202—Externally-operated valves mounted in or on the actuator
    • 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
    • F15B13/00—Details of servomotor systems ; Valves for servomotor systems
    • F15B13/02—Fluid distribution or supply devices characterised by their adaptation to the control of servomotors
    • F15B13/04—Fluid distribution or supply devices characterised by their adaptation to the control of servomotors for use with a single servomotor
    • F15B13/042—Fluid distribution or supply devices characterised by their adaptation to the control of servomotors for use with a single servomotor operated by fluid pressure
    • F15B13/043—Fluid distribution or supply devices characterised by their adaptation to the control of servomotors for use with a single servomotor operated by fluid pressure with electrically-controlled pilot valves
    • 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
    • F15B15/00—Fluid-actuated devices for displacing a member from one position to another; Gearing associated therewith
    • F15B15/20—Other details, e.g. assembly with regulating devices
    • F15B15/28—Means for indicating the position, e.g. end of stroke
    • F15B15/2815—Position sensing, i.e. means for continuous measurement of position, e.g. LVDT
    • F15B15/2861—Position sensing, i.e. means for continuous measurement of position, e.g. LVDT using magnetic means
    • 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
    • F15B13/00—Details of servomotor systems ; Valves for servomotor systems
    • F15B13/02—Fluid distribution or supply devices characterised by their adaptation to the control of servomotors
    • F15B13/04—Fluid distribution or supply devices characterised by their adaptation to the control of servomotors for use with a single servomotor
    • F15B13/0401—Valve members; Fluid interconnections therefor
    • F15B2013/0409—Position sensing or feedback of the valve member

Definitions

  • Proportional mechano-electronic actuator means
  • the invention relates to a proportional mechano-electronic actuator means for a device linearly controllable by a pressure fluid, the actuator means being intended to be connected between a pressure source and the device to be controlled, comprising a proportional magnet; a pilot control spindle arranged to be movable in a pilot control body by means of a proportional magnet for opening and closing different pressure fluid conduits; a positioner means for the device to be controlled, the positioner means being linearly controllable in two directions by means of the pilot control spindle so that the pilot control spindle tends to keep the positioner means at each particular moment in a pre ⁇ determined position corresponding to a control signal supplied by an electric control unit of the actuator means so as to linearly control the device to be controlled through a control spindle or other similar external coupling device of the actuator means.
  • a device of this type is known e.g. from EP Patent Specification 0 151 174, in which a pilot control spindle and a positioner are in mechanical contact with each other, the determination of the position of the positioner being inaccurate and its response relatively slow.
  • the object of the present invention is to eliminate the drawbacks of the prior art. This object is achieved by means of an actuator means according to the invention, which is characterized in that a position sensor electrically sensing the position of the positioner means is provided in a substantially cylindrical means defining a space where the posi- tioner means moves, the position sensor comprising a winding fitted around said means.
  • the valve according to the invention is connectable to any valve, and it is especially well suited for the control of a mobile directional valve, for instance.
  • Figures la, 2a, 3a and 4a show side views of the actuator means according to the invention in a partial section in different operating positions, the actuator ' means of Figure 4a deviating slightly from the actuator means of Figures la, 2a and 3a with respect to the arrangement of the position sensor;
  • Figures lb, 2b, 3b and 4b show pressure line coverage patterns associated with the operating posi ⁇ tions shown in the above-mentioned figures.
  • Figures la, 2b and 3a show a proportional mechano-electronic actuator means comprising a pro ⁇ portional magnet 1, a pilot control unit 30, a posi ⁇ tioner unit 40, a feed and return part 50 for pres ⁇ sure fluid, and an electronic unit 70, which are all connected fixedly together into a compact actuator means aggregate.
  • the pilot control unit 30 comprises a body 5 provided with a cylindrical boring 6 in which a ver ⁇ tically movable pilot control spindle 3 is posi ⁇ tioned.
  • the spindle 3 comprises an upper annular shoulder 7, a lower annular shoulder 8 and an annular conduit 9 positioned therebetween.
  • a spring 4 is pro ⁇ vided in the boring 6 below the pilot control spindle 3, a spindle 2 of the proportional magnet 1 moving the pilot control spindle 3 against the tension of the spring 4.
  • the body 5 further comprises a pressure fluid conduit P and a pressure fluid return conduit T communicating with the pressure fluid feed and return part 50.
  • the feed and return part 50 is positioned immediately below the pilot control unit 30.
  • the positioner unit 40 comprises a housing 10 which is attached to the side of the pilot control unit 30.
  • a rotation symmetrical cavity extends through the housing 10, and a cylinder pipe 12 of a non-magnetic material is secured in one end of the cavity within the cavity close to the pilot control unit 30.
  • a copper wire winding or coil 13 is embedded in the outer surface of the cylinder pipe 12 so as to extend around the pipe, and a positioner means 11 is arranged slideably against the inner surface of the cylinder pipe 12 in a sealed manner.
  • a control spindle 14 is attached to the end of the positioner means remote from the pilot control unit 30 for controlling a valve 60 attached to this end of the positioner unit 40.
  • a spring assembly 15 to 18 is installed within the corresponding end portion of the cavity of the housing 10; the spring assembly tends to center the positioner means 11 when the means is moved in either direction.
  • the housing 10 is attached to the side of the pilot control body 5 so that the axes of the pilot control spindle 3 and the posi ⁇ tioner means 11 are perpendicular to each other.
  • the pressure space A communicates with the boring 6 of the pilot control unit 30 by means of a conduit A extending through the body 5, and the pressure space Bl by means of a conduit B extending through the housing 10 and the body 5.
  • the pressure space B is sealed by a seal 19 in the area of the housing 10 where the spring assembly 15 to 18 is positioned.
  • the coil 13 and the means 11 are so positioned with respect to each other that the length of the portion of the means 11 remaining within the coil 13 varies with the position of the means 11. During operation within the measuring range, a certain length of the means 11 penetrated within the coil 13 corresponds to each position of the means 11.
  • the inductance of the coil 13 varies con ⁇ tinuously as a function of the position.
  • the intens ⁇ ity of the created eddy currents - and thus the sensitivity of the sensor arrangement - can be affected e.g. by controlling the force line pattern of the magnetic field of the coil 13 and increasing the intensity of the force lines in a desired manner.
  • the inductance of the coil 13 at each specific moment - and thus the posi- tion of the means 11 - is measured and converted into a pulse-length-modulated signal by means of a microprocessor.
  • the actuator means shown in Figure 4a corresponds to the actuator means shown in Figures la, 2a and 3a with the exception of the arrangement of the position sensor.
  • the position sensor 130 is wound on a spool 131 which is pushed over a cylinder pipe 120. This is another advanta- geous way of installing the position sensor around the cylinder pipe. The operating principle of the actuator means and the position sensor is not affected by this modification.
  • the actuator means aggregate operates as follows:
  • Figure la illustrates the rest state of the actuator means.
  • the return spring 4 keeps the pilot control spindle 3 and the spindle 2 of the magnet 1 in the upper extreme position, a so-called safety position ( Figure lb).
  • the shoulder 8 of the pilot control spindle 3 keeps the pressure fluid conduit P closed, whereas the conduit A and the conduit B com ⁇ municate with the return fluid conduit T.
  • the posi- tioner means 11 is maintained in its center position by the action of the centering spring 15, and it may be moved mechanically by an external force.
  • the actuator means is shown in an operation state.
  • current is supplied to the magnet 1 so that the magnet pushes the pilot control spindle 3 to a so-called center position ( Figure 3b), in which the shoulder 7 pre ⁇ vents the flow between the conduit A and the return conduit T while allowing the flow between the pressure fluid conduit P and the conduit B.
  • the posi ⁇ tion is sensed as described above by means of a signal processed by the means 11 and the micro ⁇ processor.
  • the pilot control spindle 3 remains in this position to wait for the control signal, and it may move either downward (Figure 4b) or upward (Figure 2b), depending on the difference between the external control signal and the control signal supplied by the positioner means 11.
  • the pressure fluid con- duit P is connected to the conduits A and B when the pilot control spindle 3 moves upward due to the dif ⁇ ference between the external control signal and the position signal supplied by the positioner means 11.
  • the shoulder 7 keeps the return fluid conduit T closed ( Figure 2b).
  • the positioner means 11 moves to the right due to the difference between the areas of the pressure spaces A 1 and B 1 until the signal supplied by the coil 13 corresponds to the control signal in magnitude, so that the pilot control spindle 3 returns to the center position ( Figure 3b).
  • the positioner means 11 remains in this new position as long as the control signal proportional to this position is maintained.
  • the signal difference caused by the termination of the control signal displaces the pilot control spindle 3 from the center position ( Figure 3b) to the position shown in Figure 4a, so that the pressure fluid conduit P is connected to the conduit B and the return conduit T to the conduit A.
  • the positioner means 11 moves to the left, until the signal supplied by the coil 13 corresponds to the signal of the center position in magnitude, and so the pilot control spindle 3 returns to the center position ( Figure 3b) .
  • the signal difference caused by the termination of the control signal displaces the pilot control spindle 3 from the center position ( Figure 3b) to the position shown in Figure 2a, so that the pressure fluid conduit P is connected to the conduits A and B.
  • the shoulder 7 keeps the return conduit T closed.
  • the positioner means 11 moves to the right due to the difference between the areas of the pressure spaces A 1 and B 1 until the signal supplied by the coil 13 corresponds to the signal of the center position in magnitude, and the pilot control spindle 3 returns to the center position ( Figure 3b).
  • the actuator means it operates in a volume flow controlled manner, so that when it is connected to a pressure source, its pressure is constantly the same as that of the pressure source. In other words, the entire pressure of the pressure source can immediate ⁇ ly be used to move the positioner means 11 when the control is started.
  • the volume flow control is compared with the pressure control acting against the spring, a considerable functional advantage is obtained. It is typical of a pressure-controlled device that the control pressure required to obtain a certain initial control position may be e.g. one fourth of the re- quired final pressure (initial pressure e.g. 6 bar, final pressure 25 bar); as is well-known, this causes operational disturbances and even prevents the oper ⁇ ation of the device due to viscosity problems when cold oil is employed.
  • the control pressure required to obtain a certain initial control position may be e.g. one fourth of the re- quired final pressure (initial pressure e.g. 6 bar, final pressure 25 bar); as is well-known, this causes operational disturbances and even prevents the oper ⁇ ation of the device due to viscosity problems when cold oil is employed.

Landscapes

  • Engineering & Computer Science (AREA)
  • Physics & Mathematics (AREA)
  • Fluid Mechanics (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Control Of Position Or Direction (AREA)
  • Reciprocating, Oscillating Or Vibrating Motors (AREA)
  • Valve Device For Special Equipments (AREA)
  • Fluid-Damping Devices (AREA)
  • Vehicle Body Suspensions (AREA)
  • Actuator (AREA)
  • Fluid-Pressure Circuits (AREA)
  • Electrically Driven Valve-Operating Means (AREA)
  • Networks Using Active Elements (AREA)

Abstract

L'invention se rapporte à un actionneur mécanique proportionnel pour un dispositif pouvant être commandé de façon linéaire par un fluide sous pression, l'actionneur devant être connecté entre une source de pression (P) et le dispositif (60) à commander. L'actionneur comprend un aimant proportionnel (1); un axe (3) de commande pilote agencé de façon à pouvoir être déplacé dans un corps (5) de commande pilote par l'aimant proportionnel (1) afin d'ouvrir et de fermer différents conduits (A, B, P, T) de fluide sous pression; un élément de positionnement (11) pour le dispositif (60), cet élément (11) pouvant être commandé de façon linéaire et dans deux directions par l'axe (3) de commande pilote, de sorte que l'axe (3) ait tendance à maintenir l'élément de position (11), à chaque moment particulier, en une position prédéterminée correspondant à un signal de commande fourni par une unité de commande électronique (70) de l'actionneur, afin de commander le dispositif (60) de manière linéaire par l'intermédiaire d'un axe de commande (14) ou un autre dispositif de couplage externe similaire de l'actionneur. Un capteur de position (13), détectant électriquement la position de l'élément de positionnement (11), est situé dans un élément sensiblement cylindrique (12) formant un volume dans lequel se déplace l'élément de positionnement, le capteur de position comprenant un enroulement adapté autour de l'élément cylindrique (12).
EP92906082A 1991-03-13 1992-03-11 Element actionneur mecano-electronique proportionnel Expired - Lifetime EP0577628B1 (fr)

Applications Claiming Priority (3)

Application Number Priority Date Filing Date Title
FI911256A FI90374C (fi) 1991-03-13 1991-03-13 Proportionaalinen mekatroninen toimilaite
FI911256 1991-03-13
PCT/FI1992/000067 WO1992016756A1 (fr) 1991-03-13 1992-03-11 Element actionneur mecano-electronique proportionnel

Publications (2)

Publication Number Publication Date
EP0577628A1 true EP0577628A1 (fr) 1994-01-12
EP0577628B1 EP0577628B1 (fr) 1995-12-06

Family

ID=8532114

Family Applications (1)

Application Number Title Priority Date Filing Date
EP92906082A Expired - Lifetime EP0577628B1 (fr) 1991-03-13 1992-03-11 Element actionneur mecano-electronique proportionnel

Country Status (6)

Country Link
EP (1) EP0577628B1 (fr)
AT (1) ATE131256T1 (fr)
AU (1) AU1342692A (fr)
DE (1) DE69206610T2 (fr)
FI (1) FI90374C (fr)
WO (1) WO1992016756A1 (fr)

Families Citing this family (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH0886380A (ja) * 1994-09-13 1996-04-02 Smc Corp パイロット形弁
JP3468457B2 (ja) * 1999-07-14 2003-11-17 Ｓｍｃ株式会社 位置検出機能付き切換弁
JP3696075B2 (ja) * 2000-10-06 2005-09-14 Ｓｍｃ株式会社 磁気センサー付き切換弁
CN110173478B (zh) * 2019-06-05 2020-05-05 浙江厚达智能科技股份有限公司 中药生产用驱动机构

Family Cites Families (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2674232A (en) * 1952-05-28 1954-04-06 Bendix Aviat Corp Latching mechanism
US3136224A (en) * 1960-11-04 1964-06-09 North American Aviation Inc Dual flow-synchronized electrohydraulic servo
US3279323A (en) * 1964-09-28 1966-10-18 North American Aviation Inc Electrohydraulic actuator
DE2904573C2 (de) * 1979-02-07 1983-01-27 Mannesmann Rexroth GmbH, 8770 Lohr Von einem regelbaren Elektromagneten betätigtes hydraulisches Ventil
US4569273A (en) * 1983-07-18 1986-02-11 Dynex/Rivett Inc. Three-way proportional valve
CH675752A5 (fr) * 1988-10-25 1990-10-31 Sulzer Ag

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
See references of WO9216756A1 *

Also Published As

Publication number Publication date
AU1342692A (en) 1992-10-21
DE69206610D1 (de) 1996-01-18
FI911256A (fi) 1992-09-14
WO1992016756A1 (fr) 1992-10-01
FI911256A0 (fi) 1991-03-13
EP0577628B1 (fr) 1995-12-06
FI90374C (fi) 1994-01-25
ATE131256T1 (de) 1995-12-15
FI90374B (fi) 1993-10-15
DE69206610T2 (de) 1996-05-23

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