NO312115B1 - Hydraulic valve - Google Patents
Hydraulic valve Download PDFInfo
- Publication number
- NO312115B1 NO312115B1 NO19995091A NO995091A NO312115B1 NO 312115 B1 NO312115 B1 NO 312115B1 NO 19995091 A NO19995091 A NO 19995091A NO 995091 A NO995091 A NO 995091A NO 312115 B1 NO312115 B1 NO 312115B1
- Authority
- NO
- Norway
- Prior art keywords
- slide
- valve
- sealing body
- stroke
- seat
- Prior art date
Links
- 238000007789 sealing Methods 0.000 claims description 27
- 239000007788 liquid Substances 0.000 claims description 9
- 239000000356 contaminant Substances 0.000 abstract 1
- 239000012530 fluid Substances 0.000 description 9
- 238000011109 contamination Methods 0.000 description 4
- 238000006073 displacement reaction Methods 0.000 description 2
- 239000010720 hydraulic oil Substances 0.000 description 2
- 230000010287 polarization Effects 0.000 description 2
- 230000003321 amplification Effects 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 238000000034 method Methods 0.000 description 1
- 238000003199 nucleic acid amplification method Methods 0.000 description 1
- 239000002245 particle Substances 0.000 description 1
- 230000000149 penetrating effect Effects 0.000 description 1
- 125000006850 spacer group Chemical group 0.000 description 1
- 230000007704 transition Effects 0.000 description 1
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
- F16K31/06—Actuating devices; Operating means; Releasing devices electric; magnetic using a magnet, e.g. diaphragm valves, cutting off by means of a liquid
- F16K31/0675—Electromagnet aspects, e.g. electric supply therefor
- F16K31/0679—Electromagnet aspects, e.g. electric supply therefor with more than one energising coil
-
- 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
- F16K3/00—Gate valves or sliding valves, i.e. cut-off apparatus with closing members having a sliding movement along the seat for opening and closing
- F16K3/02—Gate valves or sliding valves, i.e. cut-off apparatus with closing members having a sliding movement along the seat for opening and closing with flat sealing faces; Packings therefor
- F16K3/16—Gate valves or sliding valves, i.e. cut-off apparatus with closing members having a sliding movement along the seat for opening and closing with flat sealing faces; Packings therefor with special arrangements for separating the sealing faces or for pressing them together
- F16K3/20—Gate valves or sliding valves, i.e. cut-off apparatus with closing members having a sliding movement along the seat for opening and closing with flat sealing faces; Packings therefor with special arrangements for separating the sealing faces or for pressing them together by movement of the seats
- F16K3/207—Gate valves or sliding valves, i.e. cut-off apparatus with closing members having a sliding movement along the seat for opening and closing with flat sealing faces; Packings therefor with special arrangements for separating the sealing faces or for pressing them together by movement of the seats by means of hydraulic forces
-
- 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
- F16K39/00—Devices for relieving the pressure on the sealing faces
- F16K39/04—Devices for relieving the pressure on the sealing faces for sliding valves
Landscapes
- Engineering & Computer Science (AREA)
- General Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Physics & Mathematics (AREA)
- Electromagnetism (AREA)
- Magnetically Actuated Valves (AREA)
- Sliding Valves (AREA)
Abstract
Direktevirkende shear seal type ventil der kontaktkraften mellom sete 4 og sleide 12 overføres til avlasteren S forut for og under ny posisjonering av sleiden På denne måten reduseres friksjonskraften generert av normalkraften på. kontaktflatene 20 mellom sete 4 og sleide 12 betydelig. Ved å bruke to dobble elektromagneter 7 'og 8 får en stor skyvkraft ved starten av slaget for å overvinne den resterende hvileftiksjon,stor skyvkraft under slaget for å overvinne den resterende glidefnksjon og stor skyvkraft ved slutten av slaget når sete og sleide hullet er i ferd med å stenges for å kunne skjære over forurensningselementer som eventuelt har satt seg fast i åpningen.Direct-acting shear seal type valve where the contact force between seat 4 and slide 12 is transmitted to the unloader S before and during repositioning of the slide. In this way, the frictional force generated by the normal force on is reduced. the contact surfaces 20 between seat 4 and slide 12 significantly. Using two double electromagnets 7 'and 8 gets a large thrust at the start of the stroke to overcome the remaining rest fiction, large thrust during the stroke to overcome the remaining sliding function and large thrust at the end of the stroke when the seat and slide hole are in motion with closing in order to be able to cut over contaminant elements that may have become stuck in the opening.
Description
Denne oppfinnelse vedrører en ventil til bruk eksempelvis som retningsventil i hydrauliske system. This invention relates to a valve for use, for example, as a directional valve in a hydraulic system.
Retningsventiler for hydrauliske system forefinnes i mange utførelser hvorav sete- og sleideventiler er de mest benyt-tede, under spesielle driftsforhold, som når hydraulikkvæsken er utsatt for betydelig forurensning, er ikke de konvensjo-nelle ventilene egnet, hovedsakelig på grunn av at de hurtig utvikler innvendig lekkasje og slitasje. Directional valves for hydraulic systems are found in many designs of which seat and slide valves are the most used, under special operating conditions, such as when the hydraulic fluid is exposed to significant contamination, the conventional valves are not suitable, mainly because they rapidly develop internal leakage and wear.
En annen type ventil, den såkalte "shear seal" er tatt i bruk under slike forhold med godt resultat. Noen innarbeidet norsk navn på denne type ventil er ikke kjent. Det antas at betegnelsen "shear" i denne sammenheng kommer av at hydraulikk-væskestrålen klippes av når ventilen lukkes. I det etterføl-gende er betegnelsen "klippeventil" benyttet. Another type of valve, the so-called "shear seal", has been used under such conditions with good results. No incorporated Norwegian name for this type of valve is known. It is assumed that the term "shear" in this context comes from the fact that the hydraulic fluid jet is cut off when the valve is closed. In what follows, the term "clip valve" is used.
En klippeventil er i sin enkleste form forsynt med to for-skyvbare ventillegemer som er plassert i et hus. I én utfø-relse står det ene sylinderformede ventillegemet, tettelegemet, i rett vinkel mot midtpartiet av det andre ventillegemet, sleiden, og danner en "T". Tettelegemet, som er forsynt med en boring langs sin senterakse, er tettende forskyvbart anbrakt i en føring og forskyves mot sleiden av trykket fra omgivende hydraulikkvæske. Sleiden er forsynt med en gjennomgående boring i sitt midtparti, som, når ventilen er i åpen posisjon, korresponderer med boringen igjennom tettelegemet. Når ventilen er åpen, strømmer hydraulikkolje igjennom boringen i tettelegemet og videre inn i boringen igjennom sleiden, hvoretter den via andre kanaler føres ut av ventilhuset. Kontaktarealet mellom tettelegemets endeflate og sleidens sideflate danner et tettende areal, idet kraften fra hydrau-likkol jetrykket, som virker på tettelegemets motstående ende-parti, trykker tettelegemet mot sleiden. Når ventilen lukkes, forskyves sleiden slik at de to boringene i ventillegemene ikke lenger korresponderer. Væskestrålen "klippes" derved av, og ventilen er stengt. Overflaten av ventillegemene i de are-alene som er utsatt for kontakttrykk er polert og av meget høy hardhet. Under lukking er derfor ventilen innrettet til også, ved kvasse overganger mellom boringer og flater, å kunne klippe av forurensningspartikler som er i lukkeflaten i lukkeøyeblikket. In its simplest form, a shear valve is provided with two slideable valve bodies which are placed in a housing. In one embodiment, one cylindrical valve body, the sealing body, stands at right angles to the middle part of the other valve body, the slide, and forms a "T". The sealing body, which is provided with a bore along its central axis, is sealingly displaceably placed in a guide and is displaced against the slide by the pressure from the surrounding hydraulic fluid. The slide is provided with a through bore in its central part, which, when the valve is in the open position, corresponds to the bore through the sealing body. When the valve is open, hydraulic oil flows through the bore in the sealing body and further into the bore through the slide, after which it is led out of the valve housing via other channels. The contact area between the end surface of the sealing body and the side surface of the slide forms a sealing area, as the force from the hydraulic oil pressure, which acts on the opposite end part of the sealing body, presses the sealing body against the slide. When the valve is closed, the slide is displaced so that the two bores in the valve bodies no longer correspond. The liquid jet is thereby "cut off" and the valve is closed. The surface of the valve bodies in the areas exposed to contact pressure is polished and of very high hardness. During closing, the valve is therefore designed to also, at sharp transitions between bores and surfaces, be able to cut off contamination particles that are in the closing surface at the moment of closing.
For at ventilen skal tette tilfredsstillende, er det nødven-dig at tettelegemet trykkes mot sleiden med relativt stor kraft. Det kreves derfor også en stor kraft for å forskyve sleiden mellom posisjonene åpen og lukket. Det er vanlig å benytte seg av et forsterkertrinn, et såkalt "pilot"-trinn, for å forskyve sleiden. I et pilottrinn kan en pneumatisk eller elektrisk operert liten ventil av kjent utførelse, styre hydraulikkvæske til et stempel som igjen er koplet til og forskyver ventilsleiden. Slike forsterkertinn er meget utsatt for forurensning som befinner seg i hydraulikkvæsken, noe som ofte medfører driftsforstyrrelser av betydelig om-fang. In order for the valve to seal satisfactorily, it is necessary that the sealing body is pressed against the slide with a relatively large force. A large force is therefore also required to move the slide between the open and closed positions. It is common to use an amplifier stage, a so-called "pilot" stage, to move the slide. In a pilot stage, a pneumatically or electrically operated small valve of known design can control hydraulic fluid to a piston which in turn is connected to and displaces the valve slide. Such amplifier tins are very exposed to contamination found in the hydraulic fluid, which often results in operational disruptions of a considerable extent.
Oppfinnelsen har til formål å avhjelpe de uheldige sidene ved anvendelse av klippeventiler, særlig relatert til forsterkertrinn i klippeventiler. The purpose of the invention is to remedy the unfortunate aspects of the use of cut-off valves, particularly related to amplifier stages in cut-off valves.
Formålet oppnås i henhold til oppfinnelsen ved å delvis avlaste trykkraften fra tettelegemet mot sleiden under sleidens åpne- og stengebevegelse, hvorved sleiden kan beveges direkte, eksempelvis av en elektromagnet, og forsterkertrinnene blir overflødige. Avlastningen foretas ved at et avlastningslegeme ved tilførsel av eksempelvis elektrisk energi, utvider seg og derved trykker tettelegemet i retning bort fra sleiden. Oppfinnelsen omfatter også anvendelse av parvis koplede elektromagneter som er forbundet til sleidens respektive en-departier. Med sleiden i en av sine endeposisjoner, vil den ene elektromagrietens anker innta en inntrukket posisjon, mens den andre elektromagnetens anker vil innta en utskjøvet posisjon. Ved en hensiktsmessig polarisering av elektomagnetene ifølge kjent teknikk, er den ene elektromagneten hvis anker inntar en inntrukket posisjon, innrettet til å frastøte sitt anker, mens den andre elektromagnet hvis anker inntar en ut-skjøvet posisjon, innrettet til å tiltrekke seg sitt anker. Sammen er disse to elektromagnetene dimensjonert til å forskyve sleiden når trykkraften fra tettelegemet mot sleiden er delvis avlastet. Sleiden beveges i motsatt retning ved at elektromagnetenes polarisasjon vendes. Avlastningen av kontaktkraften mellom ventillegemene opphører så snart ventilsleiden er i ønsket posisjon, hvorved sleiden holdes fast i den inntatte posisjon. The purpose is achieved according to the invention by partially relieving the pressure force from the sealing body against the slide during the slide's opening and closing movement, whereby the slide can be moved directly, for example by an electromagnet, and the amplifier stages become redundant. The relief is carried out by a relief body expanding when, for example, electrical energy is supplied and thereby presses the sealing body in a direction away from the slide. The invention also includes the use of electromagnets connected in pairs which are connected to the respective end parts of the slide. With the slide in one of its end positions, one electromagnet's armature will occupy a retracted position, while the other electromagnet's armature will occupy an extended position. With an appropriate polarization of the electromagnets according to known technology, one electromagnet whose armature occupies a retracted position is arranged to repel its armature, while the other electromagnet whose armature occupies an extended position is arranged to attract its armature. Together, these two electromagnets are designed to displace the slide when the pressure from the sealing body against the slide is partially relieved. The slide is moved in the opposite direction by reversing the polarization of the electromagnets. The relief of the contact force between the valve bodies ceases as soon as the valve slide is in the desired position, whereby the slide is held firmly in the assumed position.
Oppfinnelsen omfatter den beskrevne metoden for avlasting av kontaktflaten mellom tettelegemet og sleiden under forskyv-ning av sleiden, og videre anvendelse av parvis samvirkende elektromagneter for direkte forskyving av nevnte sleide. Oppfinnelsen inkluderer således ikke de tekniske løsningene ved-rørende en konvensjonell klippeventil eller en elektromagnet, som begge er i og for seg kjent. The invention includes the described method for unloading the contact surface between the sealing body and the slide during displacement of the slide, and further use of pairs of interacting electromagnets for direct displacement of said slide. The invention thus does not include the technical solutions concerning a conventional clip valve or an electromagnet, both of which are known in and of themselves.
I det etterfølgende beskrives et ikke-begrensende eksempel på en foretrukket utførelsesform som er anskueliggjort på med-følgende tegninger, hvor: Fig. 1 viser i snitt skjematisk en ventil av angjeldene type i åpen posisjon; In what follows, a non-limiting example of a preferred embodiment is described which is visualized in the accompanying drawings, where: Fig. 1 schematically shows in section a valve of the type in question in the open position;
Fig.2 viser et snitt A i fig. 1; og Fig.2 shows a section A in fig. 1; and
Fig. 3 viser i snitt skjematisk ventilen ifølge fig. 1 i lukket posisjon. På tegningene betegner henvisningtallet 1 en klippeventil ifølge oppfinnelsen. Klippeventilen 1 omfatter et hus 2, et lokk 3, et tettelegeme 4, en sleide 12, og elektromagneter 7, 8. Elektromagnetene 7, 8 er forbundet til sleiden 12 ved hjelp av mellomstykker 10 respektive 11. Det koppformede lokk 3 er forsynt med en tetning 13 mot huset 2, og danner sammen med huset 2, et mellomliggende hulrom 9. Huset 2 er forsynt med en tetning 14 som hindrer væskegjennomstrømning langes tettelegemets 4 utvendige sylinderflate, og et hulrom 2', som omkranser deler av sleiden 12 og elektromagnetene 7, 8. En gjennomgående rørtilkopling 15 forbinder hulrommet 2' med et ikke vist røropplegg. En kanal 21 forbinder sleidens 12 tet-ningsflate mot huset 2 med hulrommet 9. Et avlastningslegeme 5 er anordnet mellom huset 2 og en til tettelegemet 4 forbundet ringflens 6. Tettelegemet 4 er forsynt med en gjennomgående boring 17. Hydraulikkvæske under trykk tilføres gjennom en boring 18 som munner ut i hulrommet 9, idet væsketrykket virker på tettelegemets 4 endeareal 19. Kraften fra væsketrykket mot arealet 19 forskyver tettelegemet 3 i retning mot sleiden 12 og trykker tettelegemet 4 mot denne. Når ventilen 1 er i åpen posisjon, se fig. 1, er boringen 17 posisjonert over og korresponderer med en kryssboring 16 gjennom sleiden 12. Hydraulikkvæske kan strømme fra kammeret 9, via boringen 17 og kanalen 21 til kryssboringen 16 og videre gjennom hulrommet 2' til rørtilkoplingen 15. Hydraulikkvæske er samtidig hindret i å trenge ut fra hulrommet 9 av tetningene 13 og 14. Når ventilen 1 skal lukkes, tilføres en elektrisk spenning til avlastningselementet 5 som eksempelvis ved oppvarming, utvider seg i tetningslegemets 4 aksielle retning og avlaster derved via ringflensen 6 trykket i kontaktflaten 20 mellom tettelegemet 4 og sleiden 12. Samtidig tilføres via ikke vis-te ledninger, en elektrisk spenning til elektromagnetene 7 og 8 på en slik måte at elektromagneten 8 trekker til seg sitt Fig. 3 shows a schematic cross-section of the valve according to fig. 1 in the closed position. In the drawings, reference number 1 denotes a shear valve according to the invention. The cutting valve 1 comprises a housing 2, a lid 3, a sealing body 4, a slide 12, and electromagnets 7, 8. The electromagnets 7, 8 are connected to the slide 12 by means of spacers 10 and 11, respectively. The cup-shaped lid 3 is provided with a seal 13 against the housing 2, and forms, together with the housing 2, an intermediate cavity 9. The housing 2 is provided with a seal 14 which prevents liquid flow along the outer cylinder surface of the sealing body 4, and a cavity 2', which surrounds parts of the slide 12 and the electromagnets 7 , 8. A continuous pipe connection 15 connects the cavity 2' with a pipe system not shown. A channel 21 connects the sealing surface of the slide 12 against the housing 2 with the cavity 9. A relief body 5 is arranged between the housing 2 and an annular flange 6 connected to the sealing body 4. The sealing body 4 is provided with a through bore 17. Hydraulic fluid under pressure is supplied through a bore 18 which opens into the cavity 9, as the liquid pressure acts on the end area 19 of the sealing body 4. The force from the liquid pressure against the area 19 displaces the sealing body 3 in the direction towards the slide 12 and presses the sealing body 4 against it. When valve 1 is in the open position, see fig. 1, the bore 17 is positioned above and corresponds to a cross bore 16 through the slide 12. Hydraulic fluid can flow from the chamber 9, via the bore 17 and the channel 21 to the cross bore 16 and further through the cavity 2' to the pipe connection 15. Hydraulic fluid is at the same time prevented from penetrating out from the cavity 9 of the seals 13 and 14. When the valve 1 is to be closed, an electrical voltage is supplied to the relief element 5 which, for example when heated, expands in the axial direction of the sealing body 4 and thereby relieves via the ring flange 6 the pressure in the contact surface 20 between the sealing body 4 and the slide 12. At the same time, via wires not shown, an electric voltage is supplied to the electromagnets 7 and 8 in such a way that the electromagnet 8 attracts its
anker, og derved sleiden 12 via festet 11 , mens elektromagneten 7 skyver sitt anker fra seg, og derved sleiden 12 via festet 10. Sleiden 12 forskyves derved fra åpen stilling til lukket stilling samtidig som den stenger, klipper, væske-strømmen igjennom boringene 17 og 21. Spenningen til avlastningslegemet 5 koples deretter fra, og avlastnings legemet 5 trekker seg sammen igjen slik at full kraft fra vesketrykket mot arealet 19 igjen hviler mot sleiden 12, hvorved sleiden 12 holdes i denne posisjon av friksjonskreftene mellom ventillegemene 4 og 12 i kontaktflaten 20. Spenningen koples deretter fra elektromagnetene 7 og 8. Eventuelle forurens-ninger i hydraulikkvæsken som ligger i lukkeområdet blir, ved anchor, and thereby the slide 12 via the attachment 11, while the electromagnet 7 pushes its anchor away, and thereby the slide 12 via the attachment 10. The slide 12 is thereby displaced from an open position to a closed position at the same time as it closes, cuts, the flow of liquid through the bores 17 and 21. The voltage to the relief body 5 is then disconnected, and the relief body 5 contracts again so that the full force from the bag pressure against the area 19 again rests against the slide 12, whereby the slide 12 is held in this position by the frictional forces between the valve bodies 4 and 12 in the contact surface 20. The voltage is then disconnected from the electromagnets 7 and 8. Any contamination in the hydraulic fluid located in the closing area will, by
den relative bevegelse mellom tettelegemet 4 og sleiden 12, klippet av under lukkeoperasjonen. the relative movement between the sealing body 4 and the slide 12, cut off during the closing operation.
Åpning av ventilen foregår på tilsvarende måte, men med motsatt polaritet i elektomagnetene 7 og 8. Opening of the valve takes place in a similar way, but with the opposite polarity in electromagnets 7 and 8.
En klippeventil ifølge oppfinnelsen vil forbedre driftsikker-heten vesentlig i forhold til kjente klippeventiler som er avhengig av forsterkningstrinn for å fungere. A cut-off valve according to the invention will significantly improve operational reliability compared to known cut-off valves which depend on amplification stages to function.
Claims (4)
Priority Applications (3)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| NO19995091A NO312115B1 (en) | 1999-10-19 | 1999-10-19 | Hydraulic valve |
| AU78183/00A AU7818300A (en) | 1999-10-19 | 2000-10-16 | Directly operated shear seal valve |
| PCT/NO2000/000339 WO2001029460A1 (en) | 1999-10-19 | 2000-10-16 | Directly operated shear seal valve |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| NO19995091A NO312115B1 (en) | 1999-10-19 | 1999-10-19 | Hydraulic valve |
Publications (3)
| Publication Number | Publication Date |
|---|---|
| NO995091D0 NO995091D0 (en) | 1999-10-19 |
| NO995091L NO995091L (en) | 2001-04-20 |
| NO312115B1 true NO312115B1 (en) | 2002-03-18 |
Family
ID=19903877
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| NO19995091A NO312115B1 (en) | 1999-10-19 | 1999-10-19 | Hydraulic valve |
Country Status (3)
| Country | Link |
|---|---|
| AU (1) | AU7818300A (en) |
| NO (1) | NO312115B1 (en) |
| WO (1) | WO2001029460A1 (en) |
Family Cites Families (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE3582068D1 (en) * | 1985-09-13 | 1991-04-11 | Stanley D Stearns | VARIABLE TENSIONING SYSTEM FOR SLIDERS WITH SHEAR SEAL. |
| US4793591A (en) * | 1987-12-11 | 1988-12-27 | Templeton, Kenly & Co. | Hydraulic shear seal valve including slide bearing |
-
1999
- 1999-10-19 NO NO19995091A patent/NO312115B1/en not_active IP Right Cessation
-
2000
- 2000-10-16 WO PCT/NO2000/000339 patent/WO2001029460A1/en active Application Filing
- 2000-10-16 AU AU78183/00A patent/AU7818300A/en not_active Abandoned
Also Published As
| Publication number | Publication date |
|---|---|
| NO995091L (en) | 2001-04-20 |
| AU7818300A (en) | 2001-04-30 |
| NO995091D0 (en) | 1999-10-19 |
| WO2001029460A1 (en) | 2001-04-26 |
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| Date | Code | Title | Description |
|---|---|---|---|
| MM1K | Lapsed by not paying the annual fees |
Free format text: LAPSED IN APRIL 2003 |