MAGNABEND - CIRCUIT OPERATION
Foda ya Magnabend sheetmetal idapangidwa ngati DC clamping electromagnet.
Dera losavuta kwambiri lomwe limafunikira kuyendetsa koyilo yamagetsi yamagetsi imakhala ndi chosinthira ndi chowongolera mlatho chokha:
Chithunzi 1: Kayendedwe Kang'ono:
Ndikoyenera kudziwa kuti chosinthira cha ON / OFF chikulumikizidwa kumbali ya AC ya dera.Izi zimalola kuti koyilo yamagetsi azizungulira ma diode mumlatho wokonzanso pambuyo pozimitsa mpaka kuwola kwapano mpaka ziro.
(Ma diode mu mlatho akugwira ntchito ngati "fly-back" diode).
Kuti mugwiritse ntchito motetezeka komanso mosavuta, ndikofunikira kukhala ndi dera lomwe limapereka cholumikizira chamanja cha 2 komanso 2-stage clamping.Kulumikizana kwa manja a 2 kumathandizira kuwonetsetsa kuti zala sizingagwire pansi pa clampbar ndipo kukangana kokhazikika kumapereka chiyambi chofewa komanso kumapangitsa kuti dzanja limodzi ligwire zinthu m'malo mwake mpaka kuwongolera kuyambika.
Chithunzi 2: Circuit with Interlock and 2-Stage Clamping:
Pamene batani la START likanikizidwa, magetsi ang'onoang'ono amaperekedwa ku koyilo ya maginito kudzera pa AC capacitor motero kumapanga kuwala kwa clamping effect.Njira yochepetserayi yochepetsera pano ku koyilo imaphatikizapo kutayika kwakukulu kwamagetsi mu chipangizo chochepetsera (capacitor).
Kutsekereza kwathunthu kumapezeka pomwe switch yoyendetsedwa ndi Bending Beam ndi batani la START zimagwira ntchito limodzi.
Nthawi zambiri batani la START limakankhidwa poyamba (ndi dzanja lamanzere) ndiyeno chogwirira cha mtengo wopindika chimakokedwa ndi dzanja lina.Kutsekereza kwathunthu sikungachitike pokhapokha ngati pali kuphatikizika kwa ma switch a 2.Komabe kukanikiza kwathunthu kukakhazikitsidwa sikoyenera kupitiriza kugwira batani la START.
Zotsalira Magnetism
Vuto laling'ono koma lalikulu ndi makina a Magnabend, monganso ma electro-magnets ambiri, ndi vuto la maginito otsalira.Ichi ndi kagawo kakang'ono ka maginito komwe kamakhalako maginito atazimitsa.Zimapangitsa kuti mipiringidzo ya clamp ikhalebe yolimba ku thupi la maginito motero kumapangitsa kuchotsa ntchitoyo kukhala kovuta.
Kugwiritsa ntchito chitsulo chofewa maginito ndi imodzi mwa njira zambiri zothanirana ndi maginito otsalira.
Komabe zinthuzi ndizovuta kuzipeza mumiyeso yake komanso ndizofewa mwakuthupi zomwe zikutanthauza kuti zitha kuwonongeka mosavuta pamakina opindika.
Kuphatikizika kwa kusiyana kopanda maginito mumayendedwe a maginito mwina ndiyo njira yosavuta yochepetsera maginito otsalira.Njirayi ndi yothandiza ndipo ndiyosavuta kukwaniritsa mu thupi la maginito opangidwa - ingophatikizirani chidutswa cha makatoni kapena aluminiyamu yokhuthala pafupifupi 0.2mm pakati pa phata lakutsogolo ndi pachimake musanamange mbali za maginito pamodzi.Chotsalira chachikulu cha njirayi ndikuti kusiyana kopanda maginito kumachepetsa kutulutsa komwe kumapezeka kuti kumangiridwe kwathunthu.Komanso sizolunjika kutsogolo kuphatikizirapo kusiyana kwa maginito amtundu umodzi monga momwe amagwiritsidwira ntchito pakupanga maginito amtundu wa E.
Gawo la reverse bias, lopangidwa ndi coil wothandizira, ndi njira yabwino.Koma zimaphatikizanso zovuta zochulukirapo popanga koyilo komanso mumayendedwe owongolera, ngakhale idagwiritsidwa ntchito mwachidule pamapangidwe oyambilira a Magnabend.
Kuwola kwamphamvu ("ringing") ndi njira yabwino kwambiri yochotsera maginito.
Zithunzi za oscilloscope izi zikuwonetsa mphamvu yamagetsi (yotsatira pamwamba) ndi yapano (yotsika pansi) mu koyilo ya Magnabend yokhala ndi cholumikizira choyenera cholumikizidwa modutsa kuti izidzizungulira yokha.(Kupereka kwa AC kwazimitsidwa pafupifupi pakati pa chithunzi).
Chithunzi choyamba ndi cha maginito otseguka, omwe alibe clampbar pa maginito.Chithunzi chachiwiri ndi cha maginito otsekedwa, omwe ali ndi clampbar yaitali pa maginito.
Pachithunzi choyamba voteji imasonyeza kuwola oscillation (kulira) ndi momwemonso panopa (m'munsi trace), koma pa chithunzi chachiwiri voteji si oscillate ndipo panopa sakwanitsa n'komwe m'mbuyo.Izi zikutanthauza kuti sipadzakhala oscillation wa maginito flux choncho palibe kuletsa yotsalira maginito.
Vuto ndilakuti maginito amanyowa kwambiri, makamaka chifukwa cha kuwonongeka kwa eddy panopa muzitsulo, ndipo mwatsoka njira iyi siigwira ntchito kwa Magnabend.
Kugwedezeka mokakamiza ndi lingaliro linanso.Ngati maginito ali wonyowa kwambiri kuti azitha kudzizungulira ndiye kuti akhoza kukakamizidwa kuti azizungulira ndi mabwalo omwe amapereka mphamvu momwe amafunikira.Izi zafufuzidwanso bwino kwa Magnabend.Drawback yake yayikulu ndikuti imaphatikiza ma circuitry ovuta kwambiri.
Reverse-pulse demagnetising ndiye njira yomwe yakhala yotsika mtengo kwambiri kwa Magnabend.Tsatanetsatane wamapangidwe awa akuyimira ntchito yoyambirira yomwe Magnetic Engineering Pty Ltd. Kukambitsirana mwatsatanetsatane ndi motere:
REVERSE-PULSE DEMAGNETISING
Chofunikira cha lingaliro ili ndikusunga mphamvu mu capacitor kenako ndikuitulutsa mu koyilo itangozimitsidwa maginito.Polarity iyenera kukhala kotero kuti capacitor ipangitse kusintha kosinthika mu koyilo.Kuchuluka kwa mphamvu zosungidwa mu capacitor zitha kukonzedwa kuti zikhale zokwanira kuletsa maginito otsalira.(Nkhani zambiri zimatha kupitilira ndikuyambitsanso maginito mbali ina).
Ubwino winanso wa njira ya reverse-pulse ndikuti imapanga demagnetising mwachangu kwambiri komanso kutulutsa pafupifupi nthawi yomweyo kwa clampbar kuchokera ku maginito.Izi zili choncho chifukwa sikoyenera kudikirira kuti koyiloyo iwole mpaka ziro musanalumikize kugunda kwa reverse.Pakugwiritsa ntchito kugunda kwa ma koyilo amakakamizika kukhala ziro (kenako kubwerera m'mbuyo) mwachangu kwambiri kuposa momwe kuwola kwake kukanakhalira.
Chithunzi 3: Basic Reverse-Pulse Circuit
Tsopano, nthawi zambiri, kuyika kusinthana pakati pa chowongolera ndi koyilo ya maginito ndi "kusewera ndi moto".
Izi ndichifukwa choti inductive current siingathe kusokonezedwa mwadzidzidzi.Ngati zili choncho ndiye kuti zosinthazo zidzazungulira ndipo chosinthiracho chidzawonongeka kapena kuwonongedwa kwathunthu.(Zofanana zamakina zitha kuyesa kuyimitsa gudumu lowuluka mwadzidzidzi).
Chifukwa chake, dera lililonse lomwe lingapangidwe liyenera kupereka njira yothandiza ya koyilo nthawi zonse, kuphatikiza ma milliseconds ochepa pomwe kusintha kosinthira kumasintha.
Dera lomwe lili pamwambapa, lomwe lili ndi ma capacitor a 2 okha ndi ma diode a 2 (kuphatikiza cholumikizira), amakwaniritsa ntchito zolipiritsa capacitor ya Storage pamagetsi oyipa (poyerekeza ndi mbali yakumbuyo ya koyilo) komanso imapereka njira ina ya koyilo. pompopompo pomwe kulumikizana kwapawiri kuli pa ntchentche.
Momwe zimagwirira ntchito:
Mwambiri D1 ndi C2 zimagwira ntchito ngati pampu yopangira C1 pomwe D2 ndi diode yotsekera yomwe imasunga mfundo B kuti isayende bwino.
Pomwe maginito ali ON cholumikizira cholumikizira chidzalumikizidwa ku terminal yake ya "normally open" (NO) ndipo maginito azikhala akugwira ntchito yake yanthawi zonse yolumikizira sheetmetal.Pampu yojambulira ikhala ikuyitanitsa C1 kupita kumagetsi okwera kwambiri omwe amafanana ndi mphamvu yamagetsi ya coil.Mphamvu yamagetsi pa C1 idzawonjezeka kwambiri koma idzaperekedwa mkati mwa 1/2 sekondi imodzi.
Kenako imakhalabe momwemo mpaka makinawo AZIMItsidwa.
Mukangozimitsa, relay imagwira kwakanthawi kochepa.Panthawi imeneyi, mphamvu ya koyilo yamphamvu kwambiri idzapitirizabe kuyendayenda kudzera mu ma diode omwe ali mu bridge rectifier.Tsopano, pambuyo pa kuchedwa pafupifupi 30 milliseconds kukhudzana relay ayamba kulekana.Ma coil apano sangadutsenso ma diode okonzanso koma m'malo mwake amapeza njira yodutsa C1, D1, ndi C2.Mayendedwe apanowa ndi oti awonjezeranso mtengo woyipa pa C1 ndipo iyambanso kulipiritsa C2.
Mtengo wa C2 uyenera kukhala wokulirapo kuti uzitha kuwongolera kuchuluka kwa kukwera kwamagetsi panjira yolumikizirana kuti zitsimikizire kuti arc sipanga.Mtengo wa pafupifupi 5 micro-farad pa amp ya koyilo yapano ndi yokwanira kutumizirana wina ndi mnzake.
Chithunzi 4 pansipa chikuwonetsa tsatanetsatane wa ma waveform omwe amapezeka mu theka loyamba la sekondi pambuyo pozimitsa.Njira yamagetsi yomwe ikuyendetsedwa ndi C2 ikuwoneka bwino pamtundu wofiira pakati pa chithunzicho, imatchedwa "Relay contact pa ntchentche".(Nthawi yeniyeni yowuluka imatha kuzindikirika kuchokera pamndandandawu; ndi pafupifupi 1.5 ms).
Chombocho chikangofika pamtunda wake wa NC, capacitor yosungidwa yopanda malire imalumikizidwa ndi koyilo yamagetsi.Izi sizisintha nthawi yomweyo koyilo yapano koma yapano ikuyenda "kukwera" motero imakakamizika mwachangu kupita ku ziro ndikulunjika pachimake choyipa chomwe chimachitika pafupifupi 80 ms pambuyo polumikizana ndi chosungira.(Onani Chithunzi 5).Mphamvu yaposachedwa imapangitsa kuti maginito asokonezeke bwino, zomwe zingachotse maginito otsalira ndipo clampbar ndi workpiece zidzatulutsidwa mwachangu.
Chithunzi 4: Mawonekedwe Owonjezereka
Chithunzi 5: Voltage ndi Current Waveforms pa Magnet Coil
Chithunzi 5 pamwambapa chikuwonetsa ma voliyumu ndi ma waveform apano pa coil ya maginito panthawi ya pre-clamping, gawo lonse la clamping, ndi gawo la demagnetising.
Zimaganiziridwa kuti kuphweka komanso kuchita bwino kwa dera lochotsa maginitoli kuyenera kutanthauza kuti lipeza ma elekitiromu ena omwe amafunikira kuchotsedwa.Ngakhale maginito otsalira sivuto derali litha kukhala lothandiza kwambiri kusinthira ma coil mpaka zero mwachangu kwambiri ndikutulutsa mwachangu.
Dera lothandiza la Magnabend:
Malingaliro ozungulira omwe takambiranawa atha kuphatikizidwa kukhala gawo lonse ndi 2-handed interlock and reverse pulse demagnetising monga tawonera pansipa (Chithunzi 6):
Chithunzi 6: Dera Lophatikiza
Derali ligwira ntchito koma mwatsoka ndilosadalirika.
Kuti mupeze ntchito yodalirika komanso kusintha kwanthawi yayitali ndikofunikira kuwonjezera zina zowonjezera pagawo loyambira monga momwe ziliri pansipa (Chithunzi 7):
Chithunzi 7: Dera Lophatikizana ndi Zosintha
SW1:
Ichi ndi chosinthira 2-pole kudzipatula.Imawonjezeredwa kuti ikhale yosavuta komanso kuti igwirizane ndi miyezo yamagetsi.Ndizofunikiranso kuti kusinthaku kuphatikizepo kuwala kwa neon kuwonetsa mawonekedwe a ON / OFF a dera.
D3 ndi C4:
Popanda D3 kuyaka kwa relay ndikosadalirika ndipo kumadalira pang'onopang'ono kwa mawonekedwe a mains waveform panthawi yogwiritsira ntchito chosinthira.D3 imayambitsa kuchedwa (kawirikawiri masekondi 30 milli) pakutsika kwa relay.Izi zimathetsa vuto la kutsekeka ndipo ndizothandizanso kukhala ndi kuchedwa kutsika musanayambe kugunda kwa maginito (pambuyo pake).C4 imapereka kulumikizana kwa AC kwa dera lopatsirana komwe kukanakhala kozungulira kozungulira kozungulira pomwe batani la START likanikizidwa.
THERM.SINTHA:
Kusinthaku kumakhala ndi nyumba yolumikizana ndi thupi la maginito ndipo imatseguka ngati maginito itentha kwambiri (> 70 C).Kuyiyika motsatizana ndi koyilo yopatsirana kumatanthawuza kuti imangosintha kanjira kakang'ono kudzera pa koyilo yopatsirana m'malo mwa maginito onse.
R2:
Pamene batani la START likanikizidwa, relay imakokera mkati ndiyeno padzakhala in-rush panopa yomwe imayitanitsa C3 kudzera pa bridge rectifier, C2 ndi diode D2.Popanda R2 sipakanakhala kutsutsa m'derali ndipo zotsatira zaposachedwa zitha kuwononga zolumikizana mu START switch.
Komanso, palinso dera lina pomwe R2 imapereka chitetezo: Ngati chosinthira chopindika (SW2) chisuntha kuchokera ku NO terminal (pamene chingakhale ndi maginito onse) kupita ku NC terminal, ndiye kuti nthawi zambiri arc imatha kupanga ndipo ngati Switch ya START inali ikuchitikabe panthawiyi ndiye kuti C3 idzakhala yozungulira pang'ono ndipo, malingana ndi kuchuluka kwa magetsi omwe anali pa C3, ndiye kuti izi zikhoza kuwononga SW2.Komabe kachiwiri R2 ingachepetse nthawi yayifupi iyi kukhala yotetezeka.R2 imangofunika mtengo wotsika (nthawi zambiri 2 ohms) kuti upereke chitetezo chokwanira.
Varistor:
Varistor, yomwe imalumikizidwa pakati pa ma terminals a AC a rectifier, nthawi zambiri sichita chilichonse.Koma ngati pali mphamvu yamagetsi pama mains (chifukwa cha mwachitsanzo - kugunda kwapafupi) ndiye kuti varistor imatenga mphamvu pakuwomba ndikuletsa kukwera kwamagetsi kuti zisawononge chowongolera mlatho.
R1:
Ngati batani la START likanati kukanikizidwa panthawi ya demagnetising pulse ndiye kuti izi zitha kuyambitsa arc pa relay kulumikizana komwe kungapangitse kuti C1 ikhale yaifupi (chosungira chosungira).Mphamvu ya capacitor idzatayidwa mu dera lopangidwa ndi C1, chowongolera mlatho ndi arc mu relay.Popanda R1 pali kukana pang'ono m'derali ndipo kotero kuti yapano ingakhale yokwera kwambiri ndipo ingakhale yokwanira kuwotcherera zolumikizana munjira yotumizirana zinthu.R1 imapereka chitetezo muzochitika izi (zachilendo).
Chidziwitso Chapadera Kusankhanso kwa R1:
Ngati zomwe tafotokozazi zikachitika ndiye kuti R1 itenga pafupifupi mphamvu zonse zomwe zidasungidwa mu C1 mosasamala kanthu za mtengo weniweni wa R1.Tikufuna kuti R1 ikhale yayikulu poyerekeza ndi kukana kwina kwa dera koma yaying'ono poyerekeza ndi kukana kwa koyilo ya Magnabend (kupanda kutero R1 ingachepetse mphamvu ya kugunda kwa maginito).Mtengo wozungulira 5 mpaka 10 ohms ungakhale woyenera koma kodi R1 iyenera kukhala ndi mphamvu yanji?Chomwe tikuyenera kufotokoza ndi mphamvu ya pulse, kapena mphamvu ya mphamvu ya resistor.Koma khalidwe ili silinatchulidwe nthawi zambiri zotsutsa mphamvu.Zotsutsa zamagetsi zamtengo wapatali nthawi zambiri zimakhala ndi mabala a waya ndipo tatsimikiza kuti chinthu chofunika kwambiri kuti tiyang'ane pazitsulozi ndi kuchuluka kwa waya weniweni womwe umagwiritsidwa ntchito pomanga.Muyenera kuthyola chingwe chotsutsa ndikuyesa geji ndi kutalika kwa waya wogwiritsidwa ntchito.Kuchokera pa izi, werengerani kuchuluka kwa waya ndikusankha choletsa chokhala ndi waya osachepera 20 mm3.
(Mwachitsanzo 6.8 ohm / 11 watt resistor kuchokera ku RS Components adapezeka kuti ali ndi waya wochuluka wa 24mm3).
Mwamwayi zigawo zowonjezerazi ndizochepa kukula kwake komanso mtengo wake motero onjezerani madola ochepa pamtengo wonse wamagetsi a Magnabend.
Pali gawo lina laling'ono lomwe silinakambiranebe.Izi zimathetsa vuto laling'ono:
Ngati batani la START likanikizidwa ndipo silikutsatiridwa ndikukoka chogwirira (chomwe chingapangitse kuti chiwongolero chikhale chokwanira) ndiye kuti capacitor yosungirayo sichidzaperekedwa mokwanira ndipo mphamvu ya demagnetising pulse yomwe imabweretsa kutulutsidwa kwa batani la START sichidzasokoneza makinawo. .Kenako clampbar ikakhalabe pamakina ndipo izi zitha kukhala zosokoneza.
Kuphatikiza kwa D4 ndi R3, kowonetsedwa mumtambo wa buluu mu Chithunzi 8 pansipa, perekani mawonekedwe oyenera papampu yamagetsi kuti awonetsetse kuti C1 ilipiritsidwa ngakhale kutsekereza kwathunthu sikunagwiritsidwe.(Mtengo wa R3 siwovuta - 220 ohms/10 watt ingagwirizane ndi makina ambiri).
Chithunzi 8: Kuzungulira ndi Demagnetise pambuyo pa "START" kokha:
Kuti mumve zambiri zamagawo ozungulira chonde onani gawo la Components mu "Build Your Own Magnabend"
Pazolinga zowunikira zithunzi zonse za 240 Volt AC, E-Type Magnabend makina opangidwa ndi Magnetic Engineering Pty Ltd akuwonetsedwa pansipa.
Dziwani kuti kuti mugwiritse ntchito pa 115 VAC zinthu zambiri zofunikira ziyenera kusinthidwa.
Magnetic Engineering inasiya kupanga makina a Magnabend mu 2003 pomwe bizinesiyo idagulitsidwa.
Zindikirani: Zokambirana zomwe zili pamwambazi zinali zofotokozera mfundo zazikulu za kayendetsedwe ka dera ndipo sizinafotokozedwe zonse.Mabwalo onse omwe awonetsedwa pamwambapa akuphatikizidwanso m'mabuku a Magnabend omwe akupezeka kwina kulikonse patsamba lino.
Tiyeneranso kudziwa kuti tidapanga mitundu yolimba kwambiri yaderali yomwe idagwiritsa ntchito ma IGBT m'malo motumizirana mauthenga kuti asinthe zomwe zilipo.
Dera lolimba la boma silinagwiritsidwepo ntchito pamakina aliwonse a Magnabend koma limagwiritsidwa ntchito ngati maginito apadera omwe tidapanga mizere yopangira.Mizere yopanga izi nthawi zambiri imakhala ndi zinthu 5,000 (monga chitseko cha firiji) patsiku.
Magnetic Engineering inasiya kupanga makina a Magnabend mu 2003 pomwe bizinesiyo idagulitsidwa.
Chonde gwiritsani ntchito ulalo wa Contact Alan patsamba lino kuti mudziwe zambiri.