TPHCM, THANG 9/2009

CC PHN T TRONG H THNG IU KHINCu trc ca mch iu khin v cc phn t

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C cau chap hanh

ai lng ra(tao ra s dch chuyen)

oi tng ieu khien

ai lng vao(ai lng vat ly)Lu lngAp suat

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CC PHN T TRONG H THNG IU KHINKhi nim Phn t a tn hiu: nhn nhng gi tr ca i lng vt l nh l i lng vo, l phn t u tin ca mch iu khin. V d: van o chiu, rle p sut. Phn t x l tn hiu: x l tn hiu nhn vo theo mt logic xc nh, lm thay i trng thi ca phn t iu khin. V d: van o chiu, van tit lu, van logic AND hoc OR. Phn t iu khin: iu khin dng nng lng (lu lng) theo yu cu, thay i trng thi ca c cu chp hnh. V d: van o chiu. C cu chp hnh: thay i trng thi ca i tng iu khin, l i lng ra ca i tng iu khin. V d: xy lanh, ng c

CHNG 3

CC PHN T TRONG H THNG IU KHIN

CC PHN T TRONG H THNG IU KHIN KH NN VAN O CHIUVAN CHN VAN TIT LUVAN P SUTVAN IU CHNH THI GIAN

VAN O CHIUVan o chiu c nhim v iu khin dng nng lng bng cch ng, m hay chuyn i v tr thay i hng ca dng nng lng.

VAN O CHIUKhi cha c tn hiu tc ng vo ca (12), th ca (1) b chn, ca (2) ni vi ca (3). Khi c tn hiu tc ng vo ca (12), th nng van s dch chuyn v pha bn phi, ca (1) s ni vi ca (2) v ca (3) b chn. Trng hp tn hiu tc ng vo ca (12) mt i, th di tc dng ca l xo th nng van s tr v v tr ban u.

Than van

Nong van

Lo xo

Kh nen ra (2)

Tn hieu tac ong (12)

Xa kh (3)

Nguon kh nen vao (1)

K hiu van o chiu v cc loi tn hiu tc ngChuyn i v tr ca nng van c biu din bng cc vung lin nhau vi cc ch ci o, a, b, c hay cc s 0, 1, 2, V tr "o" c k hiu l v tr m khi cha c tc ng ca tn hiu ngoi vo.i vi van c ba v tr th v tr gia k hiu "o" l v tr "khng". i vi van c hai v tr, th v tr "khng c th l "a" hay "b", thng thng v tr bn phi l v tr "khng".

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K HIU VAN O CHIUCa x kh khng c mi ni cho ng dnCa x kh c mi ni cho ng dn

Ca noi vanKy hieu theo ISO 5599Ky hieu theo ISO 1219Ca noi vi nguon (t bo loc kh)1PCa noi lam viec2, 4, 6, A, B, C, Ca xa kh3, 5, 7,R, S, T, Ca noi tn hieu ieu khien12, 14, X, Y,

K HIU VAN O CHIUBn trong vung ca mi v tr l cc ng thng c hnh mi tn, biu din hng chuyn ng ca dng kh nn qua van. Trng hp dng kh nn b chn c biu din bng du gch ngang.K hiu cc ca ni ca van o chiu

Ca 1 noi vi ca 4

Ca xa kh co moi noi cho ong dan

Ca 1 noi vi ca 2

Ca noi ieu khien 14 (Z)

12 (Y) Ca noi ieu khien

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4(B)

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K HIU VAN O CHIU

K hiu van o chiu

Trang thai

Tc ng bng tayK hiu tn hiu tc ng bng tay

Ky hieu

Mo ta

Ky hieu

Mo ta

Nut nhan tong quat

Nut bam

Nut keo

Nut bam va keo

Tay gat

Ban ap

Ban ap xoay

Nut van

Tc ng bng c, kh nn v in

Hnh dng ca mt s c cu tc ng(Operators)

VAN O CHIU 2/2 (Poppet Valve 2/2)Van o chiu 2/2, tc ng trc tip bng kh nn, phc hi v v tr ban u bng l xo. Ti v tr "khng", ca 1 b chn. Khi c tn hiu kh nn 12 tc ng, nng pittong b y xung van s chuyn sang hot ng v tr 1, lc ny ca 1 ni vi ca 2.

VAN O CHIU 3/2Van o chiu 3/2, tc ng trc tip bng kh nn, phc hi v v tr ban u bng l xo. Ti v tr "khng", ca 1 b chn, ca 2 thng kh vi ca 3. Khi c tn hiu kh nn 12 tc ng, nng pittong b y xung van s chuyn sang hot ng v tr 1, lc ny ca1 ni vi ca 2, ca 3 b chn.

CAC MACH KHI NEN C BANiu khin xy lanh tac ng mt chiu trc tip bng mt nut nhn. Yu cu: Khi tac ng vao nut nhn, pittng cua xy lanh tac ng mt chiu (xy lanh tac dung n) di chuyn i ra (dui ra). Khi nha nut nhn, pittng co lai tr v vi tri ban u.Vi xy lanh tac dung n chi co mt ng cp khi va cung la ng xa khi do o phai s dung van iu khin chi co mt ca dn khi ra iu khin.

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VAN O CHIU 3/2iu khin xy lanh tac ng mt chiu gian tip

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Van o chiu 3/2- tc ng bng c chn hai chiuVan o chiu 3/2, tc ng bng c chn hai chiu (c dng lm cng tc hnh trnh). C hai loi, v tr "khng" thng ng v v tr "khng" thng m.

Van o chiu 4/2 - tc ng bng u dVan o chiu 4/2, tc ng bng u d. y l loi van c v tr "khng", ti v tr ny ca 1 ni vi ca 2, ca 3 ni vi ca 4 (hnh a). Khi u d b tc ng s y nng pittong xung, tc ng ln vng m v lm cho ca 1 ni vi ca 4, ca 2 ni vi ca 3 (hnh b).

VAN O CHIU 5/2Van o chiu 5/2, tc ng trc tip bng dng kh nn vo t hai pha ca nng van: Khng c v tr "khng", van c c im l "nh" v tr hot ng khi khng cn tn hiu tc ng.Khi c tn hiu kh nn 12 tc ng, y nng pittong qua bn tri, lc ny ca 1 ni vi ca 2, ca 4 ni vi ca 5, ca 3 b chn. Van s gi v tr lm vic ny cho d tn hiu kh nn 12 khng cn tc ng na. Cho n khi c tn hiu kh nn 14 tc ng, nng pittong b y qua bn phi, lc ny lm cho ca 1 ni vi ca 4, ca 2 ni vi ca 3, ca 5 b chn. Van s gi v tr hot ng ny cho d dng kh nn 14 khng cn tc ng na.

VAN O CHIU 5/2Tac ng vao nut nhn, xy lanh dui ra, khi di chuyn n cui hanh trinh, cham vao cng tc hanh trinh 1.3 thi xy lanh co lai tr v vi tri ban u.

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VAN O CHIU 5/2iu khin tuy ng theo hanh trinhVi du 2: Tac ng vao nut nhn va ban u cng tc hanh trinh 1.3 bi cham, xy lanh dui ra, khi di chuyn n cui hanh trinh cham vao cng tc hanh trinh 1.4 thi xy lanh co lai tr v vi tri ban u.

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VAN O CHIU 5/3 Van o chiu 5/3, tc ng bng kh nn. y l cc loi van c v tr "khng" - v tr gia. Khi c tn hiu kh nn pha bn no tc ng th van s lm vic v tr tng ng bn . Khi khng cn tn hiu kh nn tc ng, van s tr v lm vic v tr gia v tr "khng" di lc tc ng ca l xo.

VAN CHNVan chn l loi van ch cho lu lng kh nn i qua mt chiu, chiu ngc li b chn. p sut dng chy tc ng ln b phn chn ca van v nh vy van c ng li. Van chn gm cc loi sau:Van mt chiuVan logic ORVan logic ANDVan x kh nhanh

VAN MT CHIUVan mt chiu. y l loi van c tc dng ch cho lu lng kh nn i qua mt chiu, chiu ngc li b chn. Nguyn l hot ng v k hiu van mt chiu: dng kh nn i t A qua B, chiu t B qua A dng kh nn b chn.

VAN LOGIC OR (Logic OR)Van logic OR; nhn tn hiu iu khin nhng v tr khc nhau trong h thng iu khin. Khi c dng kh nn qua ca s 1, pittong tr ca van b y sang v tr bn phi, chn ca 1(3), ca s 1 thng kh vi ca s 2. Hoc khi c dng kh nn cp vo ca 1(3), pittong tr ca van b y sang v tr bn tri, chn ca s 1, ca 1(3) ni vi ca 2.

VAN LOGIC OR (Logic OR)iu khin xy lanh tac ng mt chiu trc tip qua van logic OR

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VAN LOGIC AND (Logic AND)Van logic AND, c chc nng l nhn tn hiu iu khin cng mt lc nhng v tr khc nhau trong HTK. Khi c dng kh nn qua ca s 1, s y pittong tr ca van sang bn phi, nh vy ca s 1 b chn. Hoc l khi c dng kh nn qua ca 1(3), s y pittong tr ca van sang v tr bn tri, nh vy ca 1(3) b chn. Nu dng kh nn ng thi qua hai ca 1 v 1(3), ca s 2 s c kh .

VAN LOGIC AND (Logic AND)iu khin xy lanh tac ng mt chiu trc tip qua van logic AND

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Logic AND Shuttle ValveA single air signal at either of the ports 1 will cause the shuttle to move and block the signalIf a signals are applied at both the left hand AND right hand ports 1 only one of them will be blocked the other will be given as an output at port 2If the pressures are not equal the one with the lowest pressure is switched

VAN X KH NHANH (Quick Exhaust Valve)Khi dng kh nn i qua ca s 1, s y b phn chn di chuyn qua bn tri, chn ca x kh li. Nh vy ca s 1 thng kh vi ca s 2. Trung hp nguc li, khi dng kh nn i t ca s 2, s y b phn chn di chuyn qua bn phi, chn ca s 1 li, nh vy kh t ca s 2 c x ra ngoi.

VAN X KH NHANH (Quick Exhaust Valve)

VAN X KH NHANH (Quick Exhaust Valve)iu khin tc xy lanh qua van xa khi nhanh

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VAN TIT LUNguyn l lm vic ca van tit lu l lu lng dng chy qua van ph thuc vo s thay i tit din.C nhim v iu chnh lu lng dng chy (iu chnh vn tc hoc thi gian chy ca c cu chp hnh). Ngoi ra van tit lu cn c nhim v iu chnh thi gian chuyn i v tr ca van o chiu.

VAN TIT LU MT CHIUNguyn l hot ng: tit din Ax thay i bng cch iu chnh vt iu chnh bng tay. Khi dng kh nn i t A qua B th dng kh y mn chn ln i qua tit din ca mn chn v ca l xo, khi dng kh i t ca B qua A th mn chn b xung, dng kh ch i qua tit din ca l xo.

VAN TIT LU MT CHIU iu khin tc xy lanh qua van tit lu iu khin lu lng dong khi ng vao (a) iu khin ng ra (b) iu khin vn tc vao va ra cua xy lanh (c)

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VAN TIT LU MT CHIUiu khin vn tc xy lanh tac dung kep iu khin tc xy lanh qua van tit lu

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VAN P SUTVan an ton Van trn Van lc kt hp vi van iu p Van p sut iu chnh t xa

Van an ton c nhim v gi p sut ln nht m h thng c th ti. Khi p sut ln hn p sut cho php ca h thng, th dng p sut kh nn s thng lc l xo v nh vy kh nn s theo ca R ra ngoi khng kh, van an ton c th iu chnh c p sut

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VAN TRNVan trn nguyn tc hot ng tng t nh van an ton. Nhng ch khc l khi p sut ca vo ca van trn t n gi tr xc nh th ca vo 1(P) s thng vi ca ra 2(A) v ni vi h thng iu khin, gi tr ca p sut kh nn c xc nh bng l xo.

VAN IU CHNH P SUT(VAN GIM P)Gi p sut c iu chnh khng i, mc du c s thay i bt thng ca ti trng lm vic pha ng ra hoc s dao ng ca p sut ng vo van. Khi iu chnh trc vt, tc l iu chnh v tr ca a van, trong trng hp p sut ng ra tng ln so vi p sut c iu chnh, kh nn tc ng ln mn s qua l thng, v tr kim van thay i, kh nn qua l x kh ra ngoi. Cho n chng no p sut ng ra gim xung bng p sut c iu chnh ban u th v tr kim van tr v v tr ban u.

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Van ieu chnh ap suat khong co ca xa kh

Van ieu chnh ap suat co ca xa kh

VAN IU CHNH P SUT T XAKhi c tn hiu p sut 12 (c th t mt ngun kh nn khc) tc ng gin tip qua van trn th ca s 1 s thng kh vi ca s 2 (ca 1 ni vi ca 2).

VAN IU CHNH THI GIANRle ng chm. Rle thi gian, bao gm cc phn t: van tit lu mt chiu iu chnh bng tay, bnh trch cha, van o chiu 3/2 v tr "khng" vi ca 1 b chn. Kh nn qua van tit lu mt chiu, cn mt khong thi gian t lm y bnh cha, sau tc ng ln nng van o chiu, van o chiu chuyn i v tr, ca 1 ni vi ca 2.K hiu v biu thi gian ca role thi gian ng chm

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R LE THI GIAN NG CHM

R LE THI GIAN NG CHM

R LE THI GIAN NGT CHMRle thi gian ngt chm c nguyn l, cu to v cng nh rle thi gian ng chm nhng van tit lu mt chiu c chiu ngc li.K hiu v biu thi gian ca rle thi gian ngt chm

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CHNG 4 C CU CHP HANH(Pneumatic Actuators)

C CU CHP HANHC cu chp hanh (actuator) co nhim vu bin i nng lng khi nen thanh nng lng c hoc. C cu chp hanh co th thc hin chuyn ng thng (xy lanh) hoc chuyn ng quay (ng c khi nen, xy lanh quay).Xy lanh chuyn ng thng v xy lanh quay

PHN LOICc c cu chp hnh kh nn c ch to vi rt nhiu kiu dng, kch c khc nhau bao gm:Xy lanh tac ng mt chiu c/khng c l xo phc hi (Single acting with and without spring return)Xy lanh tac ng hai chiu (Double acting)Khng c vng m v vng m gim chn c nh Vng m gim chn c th iu chnh Vng m t trng Xy lanh khng trc dn hng (Rodless)Xy lanh quay (Rotary)Tay kp (Clamping)Xy lanh mng (Bellows)

Cu to chung ca xy lanh kh nn

1. em au truc2. Nam cham3. Ong boc ngoai4. Than5. Bac an6. em kn7. Nap xi lanh8. Cong cap kh9. Cam bien t10. Pittong11. Vong ai12. em piston13. e xi lanh14. Tiet lu

Xy lanh tac ng mt chiu c l xo phc hiXy lanh tac ng mt chiu s dung ngun nng lng khi nen tao ra chuyn ng cua nong pittng v chi tao ra chuyn ng mt chiu duy nht. Chuyn ng quay tr v co th thc hin bng lo xo.Start/Stop animation by click

Xy lanh tac ng mt chiu khng c l xo phc hiXy lanh tac ng mt chiu s dung ngun nng lng khi nen tao ra chuyn ng cua nong pittng.Chi tao ra chuyn ng mt chiu duy nht.Chuyn ng quay tr v co th thc hin bng ngoi lc hay trng lcStart/Stop animation by click

Xy lanh tac ng hai chiuXy lanh tac ng hai chiu s dung ngun nng lng khi nen cung cp cho ca hai ca vao cua xy lanh: s dung cho nhiu ng dung thc hin cac chuyn ng ra vao cua xy lanh. Chung ta co th iu khin tc cua xy lanh bng cach iu khin ap sut ca x. Khng c vng m v vng m c nh Vng m c th iu chnh Vng m t trng

Xy lanh tac ng hai chiukhng c gim chn

Xy lanh tac ng hai chiu khng co giam chn: ma sat cua pittng v thanh trong cua xy lanh tng ln, tao ra va p ln cua pittng v xy lanh cui hanh trinh.

Cac xy lanh nay ph hp danh cho vic thc hin cac chuyn ng vi vn tc thp, luc nay se tao nn s va cham nhe nhang khi n cui hanh trinh. Start/Stop animation by click

Xy lanh tac ng hai chiu vi vng m gim chn c nhXy lanh tac ng hai chiu co vng m giam chn se ngn chn s va p cua xy lanh cui khoang chay. Loai xy lanh nay cn cho hoat ng yu cu co va p nhe. Ngi ta thng s dung ia tru giam chn hoc tit lu mt chiu lam nhim vu giam chn.Start/Stop animation by click

Xy lanh tac ng hai chiuvi vng m gim chn c th iu chnh Vng m c th t iu chnh v tr gip hm tc xy lanh cui hnh trnh chuyn ng. Start/Stop animation by click

Xy lanh tac ng hai chiuc vng m t trngCac vong m mang t tinh boc xung quanh pittng tip xuc vi xy lanh khng mang t tinh. Khi pittng di chuyn thi t trng nay cung di chuyn lam ong m cac cng tc t c gn trn v xy lanh.

Start/Stop animation by click

Xy lanh khng trc dn hng (Rodless cylinder)Xy lanh khng co truc pittng co u im so vi xy lanh co truc pittng la chiu dai thit k chi bng mt na so vi xy lanh co truc pittng. Co mt s ng dung tao ra chuyn ng hai chiu vao ra ging nhau v lc tao ra cung bng nhau.Start/Stop animation by click

Xy lanh khng trc dn hng (Rodless cylinder)Start/Stop animation by click

Xy lanh khng trc hnh trnh kp (Twin stroke rodless cylinders) p ng cc ng dng yu cu khong hnh trnh chuyn ng di hoc cn nhng chuyn ng kp ng thi ngc chiu nhau. Ti s c kt ni bn trt bi dy ai. Start/Stop animation by click

Xy lanh khng trc hnh trnh kp (Twin stroke rodless cylinders)Kch thc xy lanh: 16 - 80mmHnh trnh chuyn ng ln ti 8.5 m

Chuyn ng chnh xc v ti nng. Hnh trnh chuyn ng ln ti 4.5 m

ng dng

ng dngStart/Stop animation by click

Xy lanh quay kh nn (Rotary Actuators)c dng quay cc chi tit, iu khin qu trnh ng m van, thc hin chuyn ng quay trong cc ng dng ca tay my. Pham vi quay cua xy lanh quay co th la 900, 1800, 3600. Xy lanh quayXy lanh quay thanh rng

Xy lanh quay (Rotary vane)Xy lanh quay tc ng hai chiu vi gc quay 270oStart/Stop animation by click

Xy lanh quay thanh rng(Rotary rack and pinion)Loai xy lanh nay thng dung trong cac h thng cp dao t ng cho may CNC, h thng quay goc cua Robot Moment tao ra am bao la hng s va truc quay co th quay mt vai vong va quay lin tuc, iu nay phu thuc vao chiu dai cua thanh rng. Start/Stop animation by click

Xy lanh quay thanh rng(Rotary rack and pinion)Start/Stop animation by click

Xy lanh kp(Clamping cylinder)c s dng trong mt khng gian hp ni ch cn nhng hnh trnh ngn.

Xy lanh mng (Bellows)Nguyn l hoat ng cua xy lanh mang cung tng t nh xy lanh tac dung n, xy lanh mang kiu cun co khoang chay ln hn xy lanh mang kiu hp. Do khoang chay nh nn xy lanh mang thng c dung trong iu khin, vi du trong cng nghip t (iu khin phanh, ly hp...).Dui ra khi c thi phng.

Ca

Vng gi

Mng n hi

Cun kp cht

Mt bch u

Piston rod bellowsLoi piston ny c s dng khi cn khong hnh trnh di hn mt cht so vi xy lanh chun.c p dng nhng ni piston cn c bo v khi bi bn, ct, vt th ri, ha cht n mn

Mt s loai xy lanh c bitMt s kiu tay kep (tay gp) thng gp Xy lanh kiu mm cp Xy lanh kiu t

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200

900

900

Tay kp song song

Tay kp gc

Tay kp bn knh

Tay kp 3 im

Actuators

ActuatorsCylinders symbols can be any length over lThe piston and rod can be shown in the retracted, extended or any intermediate position

Single actingSingle acting sprung instrokedSingle acting sprung outstrokedSingle acting sprung instroked magnetic * Single acting sprung outstroked magnetic * * ISO 1219-1 provides no example for magnetic cylinders

Single acting without springSingle acting normally instroked external force returnsSingle acting normally outstroked external force returnsSingle acting normally instroked magnetic external force returns Single acting normally outstroked magnetic external force returns Note: the hardware is usually double acting cylinders applied as single acting

Double actingDouble acting adjustable cushionsDouble acting through rodDouble acting magnetic *Double acting rodless **ISO 1219-1 provides no example for magnetic or rodless cylinders

Rotary actuatorsSemi rotary double actingRotary motor single direction of rotationRotary motor bi-directional

Simplified cylinder symbolsSingle acting load returnsSingle acting spring returnsDouble acting non cushionedDouble acting adjustable cushionsDouble acting through rod

LC TC NG TRONG XY LANH

LC TC NG TRONG XY LANHTrong cng thc di chung ta chia P cho 10 biu din ap sut bng n vi N/mm2 (1 bar = 0,1 N/mm2).Lc y ra ly thuyt : Lc co vao ly thuyt : Vi F : Lc y ra hay co vao l thuyt (N)D : ng kinh xy lanh (mm)d : ng kinh nong pittng (mm)P : Ap sut cua h thng khi nen tac ng ln xy lanh (bar)Lc tao ra trong qua trinh i vao va ra cua xy lanh tinh toan theo ly thuyt cua mt xy lanh bng cach nhn din tich tac dung cua pittng vi ap sut lam vic.

LC TC NG TRONG XY LANHTm lc y ra/co vo l thuyt ca mt xy lanh vi ng knh 50 mm, ng knh nng pittng l 20 mm, p sut cung cp 8 bar. 1571Newtons1319NewtonsLc y ra ly thuytF=502. 840Lc co vao ly thuytF(502-202). 840===

NG C KH NN

NG C KH NNSo sanh vi ng c in, ng c khi nen co mt vai u im quan trong sau:Ty s nng lng trn khi lng cao: CKN nhe va nho, thng co khi lng nho hn nhiu ln so vi ng c in co cung cng sut.Kha nng qua tai: Khi ng c khi nen qua tai thi se dng lai va sinh ra nhit cao. Chung co kha nng i lu nhit thng qua vo ng c va khng khi xung quanh.Co th iu khin hng va tc ng c: Tc ng c d dang iu khin bng cach gn cac van tit lu ng xa. Bng cach s dung van 5/3 vi trang thai gia ong kin cac ca, ng c khi nen co th dng lai ngay lp tc. Con ng c in, bi vi moment quan tinh cua rotor cao, se mt thi gian dng lai lu hn. Tai co th tac ng nhng nu chung ta s dung trang thai trn cua van thi ng c a bi cht va khoa lai.An toan: khng gy ra hin tng chay n.Nhc im:Gia thanh: ng c khi nen thng t hn ng c in bng cng sut c bit la kich thc nho.Hiu sut: Hiu sut cua ng c khi nen thi nho hn nhiu so vi ng c in, thng thp hn 30%. Tiu thu khi nen cao se tng gia thanh san xut. Nh vy hiu sut tng th cua h thng tng i thp khoang 20%, s dung nhiu ng c khi nen oi hoi may nen khi phai co cng sut ln hn.Co mt s kiu ng c khi nen khac nhau nhng hu ht la ng c canh gat, ng c pittng va ng c turbine. ng c khi nen tao ra chuyn ng quay lin tuc vi nhiu loai khac nhau co th quay theo 2 chiu.

NG C KH NN CNH GTrotor (1) gn lch tm vi vo ng c, co th co bn hoc nhiu hn cac ranh hng tm rotor, va mi ranh trt gn vi cac canh gat trt(2). Khi rotor quay, cac canh gat vng ra ta vao b mt bn trong cua vo ng c (3) bi lc ly tm v lc y l xo (6), vi vy cac canh gat nay lun tao thanh cac bung khi kin vi vo. lam kin trc khi rotor at c tc , mt lo xo c gn vao di ranh co tac dung y canh gat i ra. Khi nen se c cung cp van x 2 phia cua rotor qua 2 ca (4,5), co s chnh lch ap sut mi canh gat, tao ra moment lam rotor quay. Trong sut qua trinh quay, mi vong mt canh gat trt ra va vao mt ln.

1

Ca noi kh nen vao

2

3

4

5

6

7

8

Ranh vong

Lo dan kh nen vao

Roto

Canh gat

1

2

3

4

5

6

7

8

Stato

Lo dan kh

Lo dan kh nen thoat ra

H THNG IU KHIN V THIT B CHN KHNG

H THNG IU KHIN V THIT B CHN KHNGCc my gp v t vt.My hay dy chuyn lp rp.Di chuyn vt liu.My dn nhn My in n. My ng gi.

Cng nghip sn xut giy. Di chuyn film. Mm cp chn khng. H thng ht chn khng trong my p nha. Robot di chuyn trn knh

C S L THUYTKh c ht t mt th tch kn da vo s chnh lch p sut trong bung kn v xung quanh. Nu th tch kn ny gii hn bi b mt ca phu ht v chi tit, p sut khng kh s lm cho hai vt dnh li vi nhau. Lc ht ny ph thuc vo din tch b mt tip xc gia hai vt v chn khng. Trong h thng chn khng cng nghip chng ta c th s dng van ht chn khng hoc my ht chn khng. p k ng ch U

(H)

Ap suat kh quyen

Ap suat kh quyen

Ap suat chan khong

iem 0 tham chieu

0123456

654321

Cc nguyn l c bn to ra chn khng C 2 nguyn l c bn to ra chn khng trong cc h thng my mc: Phng php to chn khng bng bm ht chn khng: Thng c ng dng trong cc h thng ln, trong cng nghip. Phng php to chn khng bng van ht chn khng Venturi.Phng php s dng rng ri nht l s dng bm ht chn khng.

Phng php to chn khng bng bm chn khngBm chn khng v ng dng ca c cu ht chn khng

To chn khng bng nguyn l ng Venturi Mt trong nhng yu cu c bn ca van Venturi l phi c cung cp kh nn. Nu khng c kh nn th phi thay th bng bm chn khng.Nu yu cu lu lng chn khng khng thay i cng lu lng chn khng ln th tt hn ht l s dng bm chn khng v hiu sut nng lng cao hn so vi van Venturi.Kh nn s c cung cp cho ng vo van v i vo vi phun to ra hiu ng Venturi. Khi kh i qua khe hp s to ra p sut thp so vi p sut kh quyn, iu ny to ra p sut chn khng (p sut m) ng ht chn khng. Kh c x ra bn ngoi.

Ca chan khong

ng kh nen xa ra ngoai

ung kh nen vao

Phu ht chn khngPhu ht chn khng dng nh dnh vt bng mt lc to ra bng p sut chn khng. Phu chn khng sau s c kch hot nng ln, di chuyn chi tit vo v tr lp rp, kim tra hoc v tr cn thit no . Kt cu ca phu ht

Phu ht chn khng

Phu ht chn khngCc loi phu ht chn khng c s dng ph bin

La chn phu ht chn khngH s ma stGi tr ca h s ma st khng ch ph thuc vo vt liu cp ma st gia phu ht v chi tit m cn ph thuc vo :ng knh ca phu ht.Kiu dng v kt cu phu ht.p sut chn khng.Nhit lm vic.B mt chi tit.Vt liu phu ht chn khng. Vinyl: Vt liu hay s dng nht, gi thnh thp, c th chu ng nhit cao, hn ch mi mn. Silicon: S dng nhit cao. Cao su: y l vt liu hay s dng trong hu ht cc ng dng.

La chn phu ht chn khng

STT

Vat lieu lam pheu hut

Vat lieu chi tiet

He so nho nhat

He so ln nhat

He so tieu chuan

1

2

Silicon

Thuy tinh nha deo

0.3

0.6

0.45

0.45

0.7

0.6

0.4

0.65

0.4

0.65

0.5

0.55

0.9

Cao su cng

Van ep

Giay Carton

Giay nham 120

3

4

5

6

Silicon

Silicon

Silicon

Silicon

Polyurethane (PU)

Thuy tinh nha deo

0.55

0.8

0.65

0.85

1.25

1.0

0.55

0.8

0.45

1.0

0.7

0.7

1.2

0.55

1.05

0.7

0.75

1.25

0.8

0.6

1.05

Polyurethane (PU)

Polyurethane (PU)

Polyurethane (PU)

Polyurethane (PU)

Cao su cng

Van ep

Giay Carton

Giay nham 120

7

8

9

10

11

12

13

Perbunan (NBR)

Thuy tinh nha deo

Cao su cng

Van ep

Perbunan (NBR)

Perbunan (NBR)

Giay Carton

Giay nham 120

0.6

0.8

0.75

1

1.4

0.65

Thuy tinh nha deo

Perbunan (NBR)

Perbunan (NBR)

Cao su Fluoro (FPM)

16

17

18

0.7

0.55

0.1

0.1

Cao su cng

Giay Carton

Be mat dau

Be mat dau

Silicon

Polyurethane (PU)

Cao su Fluoro (FPM)

Cao su Fluoro (FPM)

19

20

21

22

23

24

25

26

27

28

29

30

Perbunan (NBR)

Neopren

Cao su Fluoro (FPM)

Be mat dau

Be mat dau

Be mat dau

0.1

0.1

0.1

Be mat t

Be mat t

Be mat t

Be mat t

0.2

0.3

0.2

0.3

0.2

0.3

0.2

0.3

0.2

0.3

Silicon

Polyurethane (PU)

Perbunan (NBR)

Neopren

Cao su Fluoro (FPM)

Be mat t

Silicon

STT

Vat lieu lam pheu hut

Vat lieu chi tiet

He so nho nhat

He so ln nhat

He so tieu chuan

31

32

Polyurethane (PU)

Go

Kim loai

0.5

0.5

0.5

Silicon

0.5

Polyurethane (PU)

Perbunan (NBR)

Neopren

Cao su Fluoro (FPM)

0.5

Kim loai

Kim loai

Go

Go

Go

Go

33

34

35

36

Perbunan (NBR)

Neopren

Cao su Fluoro (FPM)

Kim loai

Kim loai

0.5

0.5

Silicon

0.5

Polyurethane (PU)

Perbunan (NBR)

0.5

Neopren

Cao su Fluoro (FPM)

Knh

Knh

0.5

Knh

Knh

a

a

0.5

a

0.5

0.5

a

0.5

Knh

Be mat nham

Be mat nham

Be mat nham

Be mat nham

37

38

39

40

41

42

43

0.5

0.5

a

44

45

46

0.5

0.5

0.5

0.5

Silicon

Polyurethane (PU)

47

48

49

50

51

52

53

54

55

Perbunan (NBR)

Neopren

Cao su Fluoro (FPM)

Be mat nham

0.6

0.6

0.6

0.6

0.6

Silicon

Polyurethane (PU)

Perbunan (NBR)

Neopren

Cao su Fluoro (FPM)

La chn phu ht chn khngV tr t phu ht chn phi theo cc yu cu v kch thc, hnh dng, cng ca sn phm c gp hay di chuyn: i vi vt cng: t phu ht ti tm hoc gc ca chi tit. i vi vt mng, do: cc phu ht nn tri u trn din tch ca sn phm.Cch b tr cc phu ht i vi cc loi chi tit

ung

ung

ung

Sai

Canh tay robot

Pheu hut chan khong

Chi tiet

Day hut chan khong

Day hut chan khong

Chi tiet

Pheu hut chan khong

Canh tay robot

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