THIT K CH TO KHUN P NHA

THIT K CH TO KHUN P NHA

TRNG H S PHM K THUT HCMKHOA O TO CHT LNG CAO

H THNG CP NHA NNG(HOT RUNNER -HR)

BO CO

GVHD: TRN MINH TH UYN SVTH : L VN TI MSSV:11144168

H THNG CP NHA NNG (HOT RUNNER HR)A.CHC NNG : 1. a nha nng vo trong long khun , khi dng nha i ra t my p1. Lun gia nha nng chy trong h thng knh dnYu cu k thut:

1. Nhit phn b ng nht trn dng chy (h thng cp nhit b lng nhit mt v nhit n nh trn ton knh dn)1. Gim thiu kh nng mt p sut khi dng nha nng chy qua knh dn1. C kh nng iu khin trng thi ming phun nh mt ci van nhit

2. M : khi phun nha vo lng khun2. ng : khi m khun ly sn phm1. Chng r r trong h thng1. Phi d i mu trong mt s trng hp1. Tnh b, t bit b phn cp nhit1. D lp rp vo khun1. D dng lm sch v thay th thnh phn b mn hoc hng1. Tm manifold phi ch to chnh xc1. Tm manifold v nozzle phi gin n1. H thng dn in tr khng tip xc trc tip vi manifold nng.1. S dng nhng chi tit ph nhng ni cn thit

B.CU TRC :Chc nng : Bc cun phun:

1. K ni u phun ca my phun1. Lm kn h thng dng chy t my n vi phun1. Gim p xut khi cn1. Lc nha nng nu yu cuKnh dn phn phi nha n cc vi phun (Manifold)

1. Vn chuyn phn phi dng nha nng1. Duy tr nhit nha l mt hng s trong khi phun1. Truyn p xut cho dng nha

Vi phun (Nozzle)

1. Cp nha nng ti ming phun1. Duy tr nhit nha l mt hng s trong khi phun

Ming phun

1. Cung cp nha nng n lng khun1. Duy tr ng dn nha vo lng khun1. Ngt dng chy nha

U IM:1. Gim thi gian chu k p1. Hn ch vic s dng knh dn ngui (Cold Runner) c th nhng ph liu st li hay phi nghin li1. Hn ch lng ph nha (Phn loi,Nghin li lu tr),t tit kim lao ng v gim nng lng tiu th1. Ci thin bn v cht lng chi tit1. Gim p xut phunHN CH:1. H thng HR phi c s dng cho nhng ng dng v cho nhng vt liu ring bit1. S nguy him v nhit khi s dng cc loi nha nhy nhit1. B iu khin nhit yu cu phi chnh xc1. Gi thnh ch to cng nh bo tr cao

1.BC CUN PHUNA. Chc nng: 1. Gip dn nha t vng phun phun ca my n manifoldB. c im:1. Gia nhit cho bc cun phun v iu khin nhit ging nh cc b phn khc trong knh dn nng . C.Phn loi:3 loi c bn1. Cung phun dng m1. Cung phun c bung gim p1. Cung phun dng ng

1. Cung phun dng m1. Knh dn c cun phun dng m c th hnh tr hay hnh nn (ngn nga tht thot nha t cun phun khi nozzle b ly ra)1. Cn ph hp gia knh dn gia cun phun v knh dn ca mt nozzle1. Cung phun c bung gim p Gim p xut dng nha chy do trong h thng HR , ngn chn dng nha b cng v tht thot t Nozzle khi khun m nhanh v khng kh bn trong bc cun phun b chy1. Cung phun dng ng H tr van mt chiu trong knh dn, c th cho dng nha thng qua do vi phun b ko v cho khng kh i vo bn trong

2.KNH DN MANIFOLDA. Chc nng: Gin tip vn chuyn v phn phi dng nha nng n ming phun nozzle v n cc lng khun

B.Cu to v c im:1.Thn manifold lm t hp kim hoc thp khng g2. Rnh nha : dn nha lng chy trong n, cng nhn cng tt3.Cht gii hn : phi kn trnh r r nha hoc khng b trt khi chu p sut cao trong qu trnh hot ng, nhng cng phi d tho lp khi bo tr h thng4.Cht xuyn : m bo nha khng r r vi p xut cao5.u ren : d dng cho lp rp6.Lp bc in tr manifold : lm t kim loi d un , dn nhit tt . Cung cp v di tr nhit cho manifold7.Nhit tr hnh ng : b tr quanh manifold b nhit mt mt trn b mt manifold. Khng lm nha qu nhit s dn n chy , to vch en trn sn phmC.Yu cu k thut thit k Manifold: c lng sn phm v vt liu da trn tiu chun v c im k thut Xc nh cng vo nha ph hp Xc nh chui nozzle ph hp trn cc nhn t : i mu, thnh mng, chiu dng chy, vt liu d mn, thi gian chu trnh nhanh v mt sn phm hon ho Tnh ton s lng sn phm da trn : kch c my phun, lc kp, khong cch ngn nht gia cc Nozzle Bn thit k Nozzle cng i xng cng tt Chn nhng Manifold tiu chun vi kch thc ph hp Thit k cc chi tit khun hot runner S dng tm cavity plate cho vi phun di , tang cng v bn cho khun. Thit k knh dn ngui gia tm khun xung quanh cc vi phun Nozzle S dng tm kp (Black plate) dy ti thiu 50mm Thit b kp ph hp gia tm Back plate v tm khun gi vi khun (Nozzle cavity plate) m bo bt kn gia Manifold v Nozzle S dng mt tm cch nhit S dng cc tm insert cng lm ngui v cc knh ngui bao quanh tm inserta.Cu trc khun cho manifold:1. Tm Black plate v tm bolster tch ri1. Nhng ci hc c gia cng cho Manifold, gip cc thnh phn vng chc hn v tho lp d dng (tt c cc b phn HR iu c th tho lp c) c khong h t nht 1mm bao quanh.b.Kp chc:1. S dng bu lng kp cht gn Manifold nht m bm kp chc c.Thit k h thng lm ngui cho Black plateC mt u vo , u ra v nhng nt (plug) bt cc u cn li . Lm ngui y r quan trng v lng nhit tp trun phn ln yd.Cc kch thc quan trng ca mt Manifold:Kch thc M : b dy ca ManifoldKch thc M1 : chiu rng ca ManifoldKch thc J2 : l ng knh knh dn nha nm trong Manifold1. Tnh ton s gin n v nhit

Vi l kch thc ca Manifold (mm) L kch thc ca Manifold trong khun(kch thc gin n) (mm) L nhit ca Manifold (C) L nhit ca khun (C)L h s gin n nhit (1/C) C.VI PHUNA.Chc nng:1. Dn nha nng n ming phun, gin tip a nha t knh dn nng n lng khunB.Cu to v c ima.Cu to1Nozzle tip2 Vng m3 Cht van4 Thit b gia cng nhit5 Cp nhit in6 Thn NozzleB.c im chung1. C dy dn nhit n ming phun1. Chi tit quan trng, t c yu cu cao:3. Nhit im u v im cui ca vi phun chnh lch thp3. Cch nhit gia vi phun v khun3. Khng nha ng cng ti ming phun3. D dng lm sch, tho lp3. C kh nng thch ng vi hnh dng ca khun v tnh cht ca nha1. Vi phun c gia nhit t bn trong hay bn ngoi . Vt liu c tnh dn nhit cao hp kim ng. B phn gia nhit c t bn cnh hoc t h thng knh dn Manifold n vi phun1. t tnh nhit nn tuyn tnhC.Phn loi:1. Vi phun gia nhit ngoi1. Vi phun gia nhit trong1. Vi phun cch ly1. 1. Vi phun gia nhit ngoi

Rnh nha trn bao quanh bc Bc c bao quanh bi mt hay nhiu loi in tr khc nhau V c bao quanh mt lp kh, cch ly nhit vi lng khun Cp nhit in c gn vo Nozzle(1 in tr gn u nozzle , ci khc nm cui nozzle v ming phun) cung cp tn hiu phn hi v b iu khin nhit ca NozzleU IM : Thit lp n gin Chi ph thpNHC IM: Khng c u im v nha ng c nha ti ming phun i hi chu k nhanh duy tr trng thi chy Giai on khi ng lu n nh nhit chy Gp vn kh nng in y sn phm

1. Vi phun gia nhit trong Mt Knh dn nha chy qua mt bc . C mt u gia nhit t tm knh dn to mt hnh vnh khuyn Mt cp nhit in c t trong u gia nhit ny ly tnh hiu phn hi v b iu khin u im Gia tang s phn phi nhit Nhc im Chi ph cao hn Nhit cn bng gia cc chi tit trong khun Nhit cn bng gia cc thnh phn kh Phi tnh ton gin n gia cc chi tit ca khun

1. Vi phun kiu cch ly

Bao gm tm manifold gia nhit bn ngoi v nhit dn n lm nng c nozzle v cc nhnh, loi ny ph bin vi nhng thit k ring (vt liu dn nhit tt hp kim ng) Nozzle ni vi Manifold bng mi ghp ren c kh nng truyn nhit ln nht

u im:

Gia tng s phn phi nhit iu khin nhit tt hn Nhc im: Chi ph cao v thit k phc tp Phi tnh ton h s gin n

D. Thit k v tnh ton s gin n v nhit La chn chiu di Nozzle phi ph hp vi chiu di khun (gn nht c th) Trng lng nha phun ra trong mt Nozzle Vt liu nha v cht ph gia V tr ming phun Cc thng s quan trng trn Nozzle

Chiu di thc ca Nozzle = L + + qVi:L l chiu di loi Nozzle c la chn (mm) l gi tr gin n ca Nozzle (mm)q la khe h ming phun

Gi tr c tnh nh sau:

l chiu di Nozzle (mm) l chiu di Nozzle luc gin n (mm) L h s gin n nhit ca vt liu(1/C) l nhit b chia nha (C) L nhit ca khun (C) D. MING PHUN (GATE)A.Chc nng: Phun nha vo trong lng khunB.Yu cu k thut ca ming phun: Chng li s ng c v ngt dng chy nha Khng c ko s hay nh git Mt p sut nh Khu vc dng chy l nh nht li du vt ming phun l nh nhtC.Phn Loi ming phun:1. Ming phun dng m1. Ming phun kiu van1. Ming phun kiu van tun t1. Ming phun kiu vancore1. Ming phun dng mDng cho mi vt liu tinh th v v nh hnh ca nhaThng s: ng knh ming phun Vung lm mt ming phun iu khin nhit nh ming phun li mt vt nh trn b mt chi tit Ming phun thng ln vo Khng ph hp vi vt liu chy cao v ng sut ct cao ng kn ming phun bng ha rn u im: D ch to S dng cho mi vt liu nha Nhc im dd Vic nha b ko dy. Do nhit ming phun qu cao th cht nha c th b nha c thng xuyn qua Vic hnh thnh ui nha c th gy kh khn trong qu trinh in y khun Gii php l to hc nh hnh ht u trong li pha i din ming phun

1. Ming phun kiu van ng m cht van cho dng nha t ming phun chy vo lng khun. Cht m van c vn hnh bng thy lc Trc khi p, cht van v tr tht vo. Ming phun m rng lm cho nha d dng chy vo lng khun Trc khi nha ti ming phun ha rn hon ton th cht di chuyn n v tr ng van u im: Gim chu k p To ra ming phun hon thin khng c ko si hoc nh git. li vch nh hn so vi cc ming phun tiu chun Lm tt trn tt c cc loi nha. Tr loi nha c tc nhn gy mi mn Nhc im Cht thng khi y sn phm ra s lm vt liu ti ch h lm tng ming phun trn sn phm v tng mi mn gia cht vi l ming phun (s dng cht cn khc phc phn no) Phi bo m nh tm tt gia ming phun v cht van hn ch mi mn

1. Ming phun kiu van tun t Lc u mt ming phun s m v c in y . Khi nha chy qua ming phun th hai, ming phun ny m tip v tip tc in y ming phun th ba. Ming phun th ba m v c tip tc nh vy cho n khi in y phn cn li ca sn phm u im: Loi ny loi tr s hnh thnh ca ng hn.

1. Ming phun kiu vancore Kiu ny ng dng p nhng sn phm c dng l ti tm chi tit nh bnh rang nha, chi tit dng ng, chi tit bnh rang nha.1. Mt s kiu ng m van ming phun khc S dng van thy lc, kh nn ri kt hp vi khun mt lng khun, s dng kn dn nng, vi ming phun kiu van

TI LIU THAM KHO: THIT K V CH TO KHUN PHUN P NHA( T.S PHM SN MINH THS TRN MINH TH UYN)WEB THAM KHO : http://tai-lieu.com/tai-lieu/cong-nghe-che-tao-khuon-mau-khuon-hai-tam-1578/

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