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NGUYN TC HOT NG CA L VI SNG

Nguyn tc hot ngL vi sng hot ng da trn nguyn l mch cng hng LC. Bphn chnh ca

n gm 1 bin p cch ly. in p thcp ca bin p ny khong trn 2000V.Cun dy thcp c nn bng 1 diode cao p bin thnh in DC sau miqua 1 tin p cao. Sau mi n n pht sng cao tn. n ny tng tnhn in t2 cc c t tim bi in p cm ng ly trn bin p ( ch1 vngdy ). Anod ca n ni vi mase cn cathod ca n c ni vi cao p. Tn sdao ng ca mch l tn scng hng LC vi C l gi trca tni trn cn Lchnh l cm khng ca phn thcp bin p.Cng sut v chc iu khin trn bn phm pha trc chl ng mch

relay cho bin p hot ng v n nh thi gian dn/thi gian ngt ca bin p.Ngoi ra cn c cc bphn phkhc nh ng c quay da, qut gii nhit, bovnhit v qu dng, cng tc ca.n pht sng viba khng phi lm nhim vkhuch i m nhim vca n lto ra dao ng vi tn skhong 2,45GHZ. Nguyn tc ca n l to mt intrng cc mnh bc xsng in t. Sng in tvi tn s2,45GHz sichiu 2,45 tln mi giy, sng kt hp vi mt in ttrng sthay i chiumt cch nh kc dn theo ng dn sng, vo ngn nu ri phn xqua ligia cc bc tng ca ngn nu, v bhp thbi thc n.Nguyn tc nu chn thc nng vi mi sng in tc tn s1 Hz (hertz), sto ra mt in ttrng (nim n i) thay i chiu 1 ln trong 1 giy) . Cc sng cc ngn 2450 MHz ichiu 2,45 tln mi giy. Sng kt hp vi mt in ttrng sthay i chiumt cch nh k.Nguyn l lm vic ca L nng vi ba l truyn cc bc xviba tn s2450MHz (bc sng 12,24 cm) qua thc n t trong l . Tia viba trong l c tn sltng l 2,45 GHz cho nng lng ca chng c thhp thu bi phn tctrong thc n.Tt ccc cht lng v cc sn phm thc phm c to thnh tcc phn tthng dng lng cc in (c mt u tch in m v u kia tch indng) . Cc phn tny c cc ht tch cc v tiu cc, v vy hc xu hng cxging nh nam chm hin vi.Sng viba c sinh ra tngun magnetron, c dn theo ng dn sng, vo

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ngn nu ri phn xqua li gia cc bc tng ca ngn nu, v bhp thbithc n. Sng vi ba trong l vi ba l cc dao ng ca trng in tvi tn sthng 2450 MHz (bc sng c12,24 cm) si chiu 2.45 tln/giy. Ccphn tthc n (nc, cht bo, ng v cc cht hu c khc) shng theo

chiu cc ng sc,cc phn tny hp thnng lng tchm viba trong mtqu trnh c gi l "t nng in mi".L vi sng c nhng tm bng cng mang in tch sht hay y cc phn tctrong thc n, c bit l nhng tm bng (plate) ny lun phin nhau thay ithng xuyn in tch (in dng i thnh in m v ngc li). Cc tm bngsht hay y nhng phn tc trong thc n lm cho chng lin tc i chiu.Khi na chu ktch cc ca l vi sng thm nhp vo thc n, ht tiu cc ca ccphn tbhp dn v cgng gn kt vi lnh vc nng lng tch cc ca .

Sau , khi l vi sng nng lng khuyt na chu km, iu ngc li xy ra -Cc ht tiu cc c y li v cc ht tch cc thu ht, gy ra mt chuyn nglt a n kt qul cc phn thot ng rt nhanh nn sc rt nhiu va chm,cxt, kch ng v ma st lm cho phn tnng ln, nhit cng nng th ccphn tchuyn ng cng nhanh. V vy khi thc n hp thnng lng tchmviba, sng viba xuyn su vo cc lp bmt thc n lm cho cc phn tchuynng hn lon v sinh ra nhit. Cc phn tcha trong thc n c t nngnhanh chng v truyn nng lng cho nhau. Qu trnh ny din ra lin tc sau mtthi gian slm chn thc n.Trn thc t, nu n bt u ngay bn di bmt bn ngoi v t vo bntrong v bn ngoi, vi a snng lng c chi tiu trong cc lp bn ngoi.Tlv mc nhit phthuc vo su v mt ca thc phm,cng nh khnng dn nhit. su t nng phthuc cu to thnh phn thc n v tn ssng viba, sng viba tn sthp hn st nng thc n su hn sng viba tnscao hn. Bi v nng lng vi sng c thay i lm nng ngay sau khi nc hp thbi thc n, n khng c thlm cho thc phm phng xhoc bnhim. Khi nng lng vi sng c tt v thc phm c ly ra khi l, khngc bc xcn li cn li trong thc phm. Vvn ny, mt l vi sng ging nhnh sng in v ngngpht sng khi n c tt.

/Ch :

Cc phn tthy tinh, mt sloi nha hay giy cng kh bhm nng bi vi sngtn s2450 MHz. Nh, thc n c thc ng trong vt dng bng cc vtliu trn trong l vi sng, m chc thc n bnu chn.

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i vi kim loi hay cc cht dn in, in thay cc ht mang in nm trongcc vt ny c bit linh ng, v ddng dao ng nhanh theo bin i in ttrng. Chng c thto ra nh in ca ngun pht sng, to nn in trngmnh gia vt dn in v ngun in, c thgy ra tia la in phng gia nh

in v ngun, km theo nguy c chy n.

/Nhng li ch ca l vi sng: Nu chn thc n rt nhanh so vi cc phng php nu n ctruyn, thngthng. Cc phng php nu n ctruyn sdng nng lng t nng du, nc hockhng kh, cc l nng viba cht nng thc n nh vy tit kim chi ph vnng lng.

Cc cht bdng vn tn ti trong thc n. Cc thc n cha m (Protein) skhng brm sm khi nu trong l nngviba. This reduced oxidation means that nutrients like vitamin A and E are less

likely to be destroyed.

Thc n c t nng nhanh trong l nng viba gia c nhiu cht bdng hn so vi thc n bt nng lu hn v dnh ninh, om, hm, . . . trongni.