EP1313953A1 - Clapet antiretour deblocable pour systeme de tres fortes pressions - Google Patents

Clapet antiretour deblocable pour systeme de tres fortes pressions

Info

Publication number
EP1313953A1
EP1313953A1 EP01940379A EP01940379A EP1313953A1 EP 1313953 A1 EP1313953 A1 EP 1313953A1 EP 01940379 A EP01940379 A EP 01940379A EP 01940379 A EP01940379 A EP 01940379A EP 1313953 A1 EP1313953 A1 EP 1313953A1
Authority
EP
European Patent Office
Prior art keywords
piston
insert
push
end section
diameter
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Withdrawn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
EP01940379A
Other languages
German (de)
English (en)
Inventor
Helmut Behl
Karl J. H. Cords
Dragoljub Djenadija
Helmut Etzel
Frank Hofmann
Michael Reinert
Bruno Schneider
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.)
Bosch Rexroth AG
Original Assignee
Bosch Rexroth 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 Bosch Rexroth AG filed Critical Bosch Rexroth AG
Publication of EP1313953A1 publication Critical patent/EP1313953A1/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Withdrawn legal-status Critical Current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
    • F15B13/00—Details of servomotor systems ; Valves for servomotor systems
    • F15B13/01—Locking-valves or other detent i.e. load-holding devices
    • 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
    • F15B2211/00—Circuits for servomotor systems
    • F15B2211/30—Directional control
    • F15B2211/31—Directional control characterised by the positions of the valve element
    • F15B2211/3122—Special positions other than the pump port being connected to working ports or the working ports being connected to the return line
    • F15B2211/3127—Floating position connecting the working ports and the return line
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
    • Y10T137/00—Fluid handling
    • Y10T137/7722—Line condition change responsive valves
    • Y10T137/7837—Direct response valves [i.e., check valve type]
    • Y10T137/7876—With external means for opposing bias

Definitions

  • the invention is based on an unlockable check valve which should be usable for very high system pressures and which has the features from the preamble of claim 1.
  • Check valves readily allow a pressure medium flow from a first outlet to a second outlet, the closing member being lifted off a seat by a force generated by the pressure in the first outlet against the force exerted by the pressure in the second outlet and against the force of the closing spring. Since the closing element is usually acted upon by the pressures on surfaces of the same size, a pressure is set in the first outlet which is higher than the pressure in the second outlet by a pressure difference equivalent to the force of the closing spring. The closing spring is only weak in order to keep losses through the valve low, unless you want to deliberately accumulate the pressure medium in the first outlet. The flow through a check valve in the direction from the second outlet to the first outlet is only possible by additional measures by which an unlockable check valve is created. There is then an abutment part which can engage the closing element in the opening direction and lift it off the seat against the force of the closing spring and against the pressure difference between the first and second outputs.
  • DE 197 14 505 A 1 discloses an unlockable check valve which has all the features from the preamble of claim 1.
  • the check valve shown has a valve housing with a continuous receiving bore, which is stepped and is composed essentially of three sections. In the two outer sections, the diameter of the tion larger than in a central section into which the two outer sections merge in steps lying in radial planes. In the two outer sections, high-strength inserts which are exposed to the system pressure and inserts which serve to guide an pushing piston are introduced.
  • the middle section of the receiving bore is divided by a piston collar of the pushing piston into two annular spaces, one of which can be supplied with control pressure via a pilot valve to control the check valve or can be relieved to a tank and the other is permanently connected to a pressure medium reservoir and one Includes return spring for the push piston. It has been found that in the known check valve the poppet is not always smooth to the desired extent.
  • DE 198 56 018 A1 also discloses an unlockable check valve which has all the features from the preamble of claim 1 and which is also used in particular in systems for the internal high-pressure forming of tubular semi-finished products.
  • the tendency of the push-up piston to jam has been reduced by the fact that the receiving bore in the area of the inserts and between them, apart from possibly existing, short indentations in the axial direction, has essentially the same diameter, so that it can be processed from just one side of the valve housing, i.e. without changing the position of the valve housing or the tool.
  • a spacer bush is arranged axially between two inserts, which ensures a fixed distance between two inserts on different sides of the piston collar, even if the diameter of the receiving bore remains the same.
  • the insert close to the piston collar on each side of the piston collar is made from a metallic material with good sliding properties, for example from a copper-beryllium alloy, and has a very close play on its inner diameter over its entire axial extent to the corresponding end section of the push-up piston so closely along its entire axial length the corresponding end section.
  • the invention is therefore based on the object of developing an unlockable check valve with the features from the preamble of claim 1 in such a way that the tendency of the pushing piston to jam is reduced.
  • an unlockable check valve according to the preamble of claim 1 according to the invention in that this valve is additionally equipped with the features from the characterizing part of claim 1.
  • the invention is based initially on the knowledge that the stiffness or even the jamming of the opening piston in the known valves is also due to a deformation of the first inserts close to the piston collar. The deformation is caused by the high-pressure seal, which is received in the recess of the second insert and is axially supported on the first insert close to its inside diameter. At very high pressures, the force exerted by the high pressure seal on the first insert is so great that the insert deforms while reducing the inside diameter and the pushing piston jams.
  • the first insert only has a guide diameter for the end section of the push-up piston only over a short distance from its end facing the piston collar.
  • the inner diameter of the insert does not decrease within the specified distance when it is deformed. Outside the specified distance, the inside diameter of the first insert is chosen to be so large that, despite a reduction in the inside diameter associated with the deformation, no jamming of the pushing piston is caused.
  • the support ring which is located axially between the high-pressure seal and the first insert in a receptacle formed between the two inserts and open radially towards the end section of the push-up piston located, has large play in the receptacle on its outer diameter, so that changes in the diameter of the receptacle caused by deformation do not affect the support ring.
  • This also has a significantly smaller outer diameter than the inserts, so that the point of application of the force exerted by the high-pressure seal and the contact point of the support ring on the first insert are at least approximately axially one above the other and the support ring is also hardly deformed immediately.
  • the first insert preferably has a play of at least 1/10 mm, preferably 2/10 mm, in front of its section with the guide diameter radially to the end section of the push-up piston. This means that the distance to the piston is large enough to avoid jamming despite deformation. On the other hand, a radial seal between the insert and the end section is axially supported so far that it does not immigrate the existing gap.
  • the outer diameter of the support ring is about 1.1 times as large as the diameter of the recess for the high-pressure seal, so that it extends radially only relatively little beyond the high-pressure seal, so that there is not too great a misalignment between the point of force application by the high-pressure seal and the location of the support ring on the first use can occur.
  • the radial play between the support ring and the end section of the push-up piston is very small, so that immigration of part of the high-pressure seal into the radial gap between the support ring and end section of the push-up piston is avoided with a high degree of certainty.
  • FIG. 1 shows the hydraulic circuit diagram
  • Figure 2 shows a longitudinal section through the embodiment of a check valve according to the invention.
  • the circuit diagram according to FIG. 1 represents only a section of the hydraulic part of an internal high-pressure conversion system.
  • the most important part of the hydraulics of such a system is a pressure intensifier 10, which contains a differential piston 12 in a multi-part housing 11, the area ratio of which determines the pressure ratio.
  • the diameter of the differential piston 12 on a secondary-side piston section 13 is significantly smaller than on a primary-side piston section 14.
  • the latter divides an interior of the housing 11 into an annular space 15 and a cylinder space 16.
  • the two rooms are connected via Pakistantechnische ⁇ 17 and 18 with a proportionally adjustable directional valve 19, the two working lines in its middle rest position and thus the annular space 15 and the cylinder space 16 via a tank connection T with a Connect the tank.
  • the annular space 15 is connected to a hydraulic pump 20 via a pump connection P, while the cylinder space 16 remains connected to the tank.
  • the cylinder chamber 16 is connected to the hydraulic pump and the annular chamber 15 to the tank.
  • a position sensor 23 detects the position of the differential piston 12 with respect to the housing 11.
  • the space 24 in front of the end face of the secondary-side piston section 13 is connected, on the one hand, to a reservoir 26, which contains a water-based hydraulic fluid, via a simple check valve 25, which opens towards it.
  • a releasable check valve 30 according to the invention is connected to the pressure chamber 24, through which the pressure chamber 24 can flow without further pressure medium to a line 31 which can be connected to the semi-finished product to be formed.
  • the line 31 is also connected to the reservoir 26 via a check valve 32 opening towards it.
  • the semi-finished product is filled with pressure fluid from the reservoir 26 via the line 31 and the check valve 32, and a pump can also be arranged between the reservoir 26 and the check valve 32, which causes a filling up to a certain pressure.
  • the directional control valve 19 is then brought into its second working position, in which hydraulic oil is supplied to the cylinder chamber 16 of the pressure intensifier 10 by the pump 20.
  • the differential piston 12, viewed in FIG. 1 moves upward and displaces pressure fluid from the pressure chamber 24 via the unlockable check valve 30 into the line 31, so that the pressure in the semi-finished product to be deformed increases.
  • the increase in volume due to the deformation and the level of the final pressure one or more strokes of the differential piston 12 are necessary.
  • the directional control valve 19 is brought into its first working position, so that the differential piston 12 travels downward and out of the storage tank via the check valve 25. container 26 hydraulic fluid is sucked into the pressure chamber 24.
  • pressure fluid is again pressed out of the pressure chamber 24 via the check valve 30 into the line 31.
  • the check valve 30 is unlocked by applying a control pressure to a control channel 33, so that the space inside the workpiece and the line 31 can be decompressed by retracting the differential piston 12.
  • FIG. 1 The structure and the mode of operation of the check valve 30 are shown in more detail in FIG.
  • the exemplary embodiment of a check valve according to the invention shown there has a valve housing 35 through which a receiving bore 36 passes, the axis of which is referred to as valve axis 37.
  • the receiving bore 36 has, apart from two internally threaded sections 38 at its two ends and apart from shallow recesses 39, 40, 41, 42 and 43 further inside the same diameter and can be in the range of this same diameter from only one side of the valve housing 35 can be edited.
  • a total of six parts are inserted axially braced against one another in the receiving bore 36.
  • high-strength inserts 44 and 45 are screwed into the sections 38 of the receiving bore 36, each of which has a threaded bore 46 or 47 in the valve axis 37, which serve as the first or second outlet of the valve and to which a pressure line can be connected in each case ,
  • the inserts 44 and 45 dip over the sections 38 into the area of the constant diameter of the receiving bore 36 and are centered therein.
  • the insert 45 has an inwardly open blind bore 48 which is connected to the threaded bore 47 via a narrower channel 49 and which receives and guides a closing member 50 which is loaded by a weak closing spring 51 in the direction out of the blind bore 48.
  • the insert 45 is followed axially by a likewise high-strength, disk-shaped insert 55 with a double-stepped central passage 56.
  • the insert 55 serves as a seat for the closing member 51 around the central passage.
  • the insert 55 is followed by a disk 60 with a central passage 61, then a spacer bushing 62, the inner diameter of which is substantially larger than the diameter of the central passage 61 in the disk 60 , then another disk 60 with a central passage 61 which is identical to the former
  • Washer 60 but mounted opposite to this, and then insert 44. Similar to insert 45, the latter has an inwardly open blind hole 63, which is, however, less deep than blind hole 48 and also has a smaller diameter. Apart from slight differences, this diameter corresponds to the diameter of the central passages 61 in the disks 60 and the diameter of the central section of the central passage in the insert 55.
  • the blind bore 63 is also connected to the threaded bore 46 via a channel 64 with a narrower diameter.
  • an impact piston 70 is received, with the aid of which the closing member 50 is lifted from its seat against the force of the closing spring 51 and against a force generated by the pressure in the second outlet 47 of the valve can be.
  • the push-up piston has a piston collar 71 located inside the spacer bush 62, which divides the space enclosed by the disks 60 and the spacer bush 62 into two annular spaces 72 and 73.
  • the annular space 72 can be acted upon by a control pressure via an external connection 75 and with the aid of a pilot valve (not shown in more detail) or can be relieved of pressure.
  • a pilot valve not shown in more detail
  • the other annular space 73 is connected to an oil container via a second outer connection 77 for volume compensation and for draining off leakage fluid also receives a return spring 78 for the push piston 70.
  • a sleeve 74 is located in the annular space 73 radially between the return spring and the spacer bush 62, through which the stroke of the push piston 70 is limited. This therefore does not strike the disk 60 close to its inner diameter, where there is also the risk of material deformation due to an annular groove 69 of the disk 60 which is located at a short distance from the end face facing the annular space 73 and receives a seal 68.
  • the push-up piston On both sides of the piston collar 71, the push-up piston has shaft-like end sections 79 and 80 with which it plunges through the central passages 61 of the disks 60 and into the blind bore 63 of the insert 44 or into the central passage 56 of the insert 55.
  • the closing member 50 Toward the closing member 50, one end section 80 is extended by a finger 81, which can act on the closing member 50 through the narrowest section of the central passage 56 of the insert 55. In the shown resting position of the pushing piston 70 there is a small distance between the finger 81 and the closing member 50.
  • the flow path between the exits 46 and 47 of the valve leads axially through the pushing piston 70, which for this purpose has a long axial bore 82 which is located in the blind bore 63 of the insert 44 opens into it, and has several small oblique bores 83 at the foot of the finger 81.
  • a high-pressure seal 86 is received, which is acted upon axially in the direction of the disk 60 by the high pressure present in the passage 56, but of course also acts radially towards the push piston 70.
  • the high-pressure seal consists of a guide ring resting on the push-up piston, an elastomeric O-ring lying in a groove of the guide ring that is open to the outside, and a wedge-shaped metallic ring lying on the outside against a conically tapering surface on the guide ring.
  • the seal 68 also acts radially in the annular groove 69 of the disk 60.
  • each disk 60 has a receptacle 87 which is open axially to the insert 44 or 55 and radially towards the end section 79 or 80 of the pushing piston 70 and from which a support ring 88 is received, which is made of the same material with good sliding properties as the washers 60 for Example of a copper-beryllium alloy, which is guided with the tight play of about 2/100 mm at the end section 79 or 80.
  • the high-pressure seal 86 bears against this support ring 88.
  • the outer diameter of the support ring 88 is only about 1.1 times as large as the outer diameter of the high-pressure seal 86 and the recess 84 receiving it, while the outer diameter of the disks 60 is more than 2.5 times as large.
  • the diameter of the receptacle 87 is at least so much larger than the outer diameter of the support ring 88 that, even when the diameter of the receptacle 60 is reduced, it is not loaded from the outside radially due to forces acting on the disk 60. When a force is introduced from the high-pressure seal 86 onto the support ring 88, this force is in any case not passed radially further outside than on the outer diameter of the support ring and thus almost exactly opposite to the disk 60.
  • the receptacle 87 and the support ring 88 are dimensioned such that the support ring has a sufficiently great stiffness even with the maximum possible radial offset of the force transmission points between it, the high-pressure seal and the disk 60.
  • the support ring extends axially approximately over 1/5 of the axial length of the disks 60. It could also be longer, but then more machining of the disks 60 would then be necessary.
  • a plurality of radial bores 93 pass through each disk 60
  • the seals in the disk 60 between the spacer bush 62 and the insert 55 seal off spaces in which the pressure is essentially the same. Their main function is to separate different hydraulic fluids.
  • the annular space 73 is usually filled with oil, while the pressure medium used for the high pressure forming is water.
  • the first outlet 46 is connected to the pressure chamber 24 of the pressure booster 10 and the second outlet 47 is connected to the line 31.
  • the pressure booster displaces water from the pressure chamber 24, this flows through the channels 64, 82, 83, 56, via the closing member 50 lifted from its seat and via the channel 49 in the insert 45 to the second outlet 47.
  • the annular space 72 is acted upon by control pressure via the external connection 75, so that the pushing piston 70 moves towards the closing member 50 and lifts it from its seat.
  • the lifting takes place against the force of the return spring 78 and against a compressive force which is caused by a possible pressure difference between the outlets 45 and 46 and by different contact surfaces for the pressures in the outlets 46 and 47 on the closing member 50, and against which is practically negligible small force of the closing spring 51.
  • the pressure force can be made practically zero at the beginning by a pressure-controlled movement of the differential piston 12.
  • a more or less large amount of pressure fluid must flow from line 31 via valve 30 into pressure chamber 24, as a result of which a pressure difference occurs via closing element 50.
  • the closing member must be kept open by the push piston 70. This is achieved due to the large diameter of the piston collar 71 with control pressures that can usually be built up today with hydraulic pumps.

Landscapes

  • Engineering & Computer Science (AREA)
  • Physics & Mathematics (AREA)
  • Fluid Mechanics (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Check Valves (AREA)
  • Safety Valves (AREA)

Abstract

L'invention concerne un clapet antiretour déblocable, destiné à être utilisé dans un système de très fortes pressions, ainsi qu'un logement de clapet (35) comportant un orifice de réception (36) traversant, disposé dans un axe du clapet (37) et un piston de poussée (70), qui peut être soumis à l'action d'une pression motrice sur une embase du piston (71) pour débloquer un élément de fermeture (50). Ce piston de poussée est guidé dans le sens de l'axe du clapet des deux côtés de l'embase (71) sur des sections terminales (79,80) de diamètre au moins approximativement identique. Dans l'orifice de réception et sur chaque côté de l'embase du piston sont disposés deux inserts (60) dans lesquels plonge une section terminale du piston de poussée. Cette section terminale est guidée dans un premier insert, situé à proximité de l'embase du piston et façonné en matériau métallique présentant de bonnes propriétés de glissement. Un deuxième insert (44,55), suivant le premier insert, est doté d'un joint à haute pression (86) adjacent radialement à la section terminale du piston de poussée (70) et appuyé axialement contre le premier insert. L'invention est caractérisée en ce que le premier insert est pourvu d'un diamètre de guidage pour le piston de poussée seulement sur une courte distance, sur sa face frontale orientée vers l'embase du piston. En outre, un support annulaire (88) est disposé axialement entre le joint à haute pression et le premier insert, dans un logement (87) dont le diamètre est sensiblement plus petit que le diamètre extérieur des inserts (44,60,55). Ce support annulaire, également réalisé en matériau métallique présentant de bonnes propriétés de glissement, est façonné avec un faible jeu par rapport à la section terminale du piston de poussée et avec un jeu radial important par rapport au logement.
EP01940379A 2000-08-31 2001-04-28 Clapet antiretour deblocable pour systeme de tres fortes pressions Withdrawn EP1313953A1 (fr)

Applications Claiming Priority (3)

Application Number Priority Date Filing Date Title
DE10042716A DE10042716A1 (de) 2000-08-31 2000-08-31 Entsperrbares Rückschlagventil für sehr hohe Systemdrücke
DE10042716 2000-08-31
PCT/EP2001/004806 WO2002018799A1 (fr) 2000-08-31 2001-04-28 Clapet antiretour deblocable pour systeme de tres fortes pressions

Publications (1)

Publication Number Publication Date
EP1313953A1 true EP1313953A1 (fr) 2003-05-28

Family

ID=7654380

Family Applications (1)

Application Number Title Priority Date Filing Date
EP01940379A Withdrawn EP1313953A1 (fr) 2000-08-31 2001-04-28 Clapet antiretour deblocable pour systeme de tres fortes pressions

Country Status (5)

Country Link
US (1) US6820645B2 (fr)
EP (1) EP1313953A1 (fr)
JP (1) JP2004529291A (fr)
DE (1) DE10042716A1 (fr)
WO (1) WO2002018799A1 (fr)

Families Citing this family (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20070241297A1 (en) * 2006-04-13 2007-10-18 Honeywell International, Inc. Guided pneumatic second stage switching valve
WO2014149107A1 (fr) 2013-03-15 2014-09-25 Waveconnex, Inc. Dispositif de communication sécurisé ehf
DE102013014673A1 (de) 2013-09-04 2015-03-05 Hydac Fluidtechnik Gmbh Lasthalteventil
JP7320924B2 (ja) * 2018-05-22 2023-08-04 ナブテスコ株式会社 流体圧バルブ
WO2023091538A1 (fr) 2021-11-17 2023-05-25 Swagelok Company Clapet antiretour

Family Cites Families (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE1943693C3 (de) * 1969-08-28 1981-07-16 Robert Bosch Gmbh, 7000 Stuttgart Federbelastetes Rückschlagventil
FR2058412B2 (fr) * 1969-08-28 1973-05-25 Bosch
DE3247420A1 (de) * 1982-12-22 1984-07-05 Mannesmann Rexroth GmbH, 8770 Lohr Hydraulisch entsperrbares rueckschlagventil
US4624445A (en) * 1985-09-03 1986-11-25 The Cessna Aircraft Company Lockout valve
DE3904978C2 (de) 1989-02-18 1994-01-27 Daimler Benz Ag Dichtring, insbesondere aus Metall
JP3451283B2 (ja) 1994-06-17 2003-09-29 Ｓｍｃ株式会社 バランス形直動電磁弁
DE19714505B4 (de) 1997-04-08 2006-06-22 Bosch Rexroth Aktiengesellschaft Rückschlagventil
DE19856018A1 (de) 1998-12-04 2000-06-08 Mannesmann Rexroth Ag Entsperrbares Rückschlagventil für sehr hohe Systemdrücke

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
See references of WO0218799A1 *

Also Published As

Publication number Publication date
DE10042716A1 (de) 2002-03-14
US6820645B2 (en) 2004-11-23
US20040094207A1 (en) 2004-05-20
WO2002018799A1 (fr) 2002-03-07
JP2004529291A (ja) 2004-09-24

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