- ti os6 truy~n.
§3.7 Tl1 DONG KHONG CHE THANG MAy
DUNG cAc PHAN TtJ LOGIC
D~ nAng eaa dci tin c~y trong qua trlnh ,ho~t d¢ng cua thang may, h~ th6ng tv dqng kh6ng eM' h~ truy~n dOng di~n thang may da. dung cae phl1n tit phi ti~p di~m (philD ttl lOgic). tJng dt,mg cae pht'in ttl' lOgic trong m~ch di~u khi4n cho phep xAy dvng mOt M th6ng di~u khi~n v(i:j 86 h1Qng phttn ttl di~u khiA'n IiI. it nhilt.
Sa dd tv dOng kh6ng cht'! thang mAy dung cAe ph£ln ttl' lOgic giO'i thi~u tr~n hinh
3 - 10. DAy Iii. sa d6 kh6ng ch~ dan gii'ln nhilt : bu6ng thang ndng l~n d~n rn¢t trong nAm t~ng, nhung khi h(l, chi h(l xu6ng tiing mOt.
C6ng U.C chuy~n d6i tl1ng dung bl) cam bi~n vi tri bing t~ bito quang di~n IF -7- 5F dfil.t trl!n cae tl1ng tuong ung.
H(lD cht'! hanh trinh l~n vA hAnh trlnh di xu6ng M.ng hai c6ng tac hi'lnh trlnh phi ti€p diA'm HeN vi'!.. HeR (hai cOng tde hAnh trlnh nAy cling gi6ng nhu cOng tAc chuygn d6i tdng). Tr~n so d6 khOng bi~u di.l!n m~h hlc cUa d¢ng co truy~n dOng thang mliy, nhung clin hi~u cOngtActo nAng N s~ ddng m~ch cho dOng co nAng bu6ng thang di l~n, cOngtActa h~ H ddng m~ch cho dOng co h~ bu6ng thang. Di~u khign thang may bAng cac nut him phi ti~p dU!m 2DT + 5DT lAp trong bu6ng thang vA mqt nut b.§:m g9i tang lap c'J ctia bing mOt lGT.
Tr~n so d6, cAm bi~n IF + 5F, HCN vA HCH (6 vu6ng t6 d~m) co mllc lOgic "In va khi co tac dOng tii: Mn ngoi'li IA muc'IOgic "0", cAm bi€n 2DT + 5DT va lGT, co muc lOgic "0" vA khi tac dOng len no se co muc 16gic np.
Xet nguyen ly litm vi~c cua h~ th6ng : N€u mu6n lAn tling nitm, ltn nut an 5DT, dliu ra cua phtrn tti "HO';'C" 5H cO muc lOgic nl" va muc do dua vao I dtiu vi'lo cua phtin tu "VAn 5V. Til b¢ cAm bi€n 5F dua vao dau vao thll hai cua phlin til 5V muc lOgic nl" (Ilng vai khi 5F chua bt tac dc)ng Mn ngoAi). Tin hi~u dt'iu ra cua pht1n ttt 5V co muc lOgic nl". Tin hi~u ra vAn cd muc 16gic nl" kg ca khi ta kMng tac dOng I~n nut Mm 5DT vi co mli,lch tl,l duy trl Ia'y til dt'iu ra cua 5V dua vao dau vao 5H, kh6ng cho phep 5H chuygn tr~ng thai. Tin hi~u 1'a cO muc lOgic "1" dua vAo mOt trong b6n dau vao cua phltn tti "HO';'C" 6H. Tin hi~u ra cua phdn tti "HO';C" 6H cd mllc lOgic "1" dua vAo mOt t1'ong ba dt1u vAo cUa phan tti ~vA" 6V. Tin hi~u thll hai phlin ttt "vA - DAO" ID- cd muc lOgic "1" (do dt1u 1'a cu~ lV cd muc lOgic "0"). TIn hi~u til dliu 1'a cua cOng tAc hAnh trlnh HCN cd muc lOgic "1" dua vAo ddu vAo thll ba cUa phlin til 6V. Tin hi~u dt1u ra cua pht1n tit 6V cO muc lOgic "P qua khdu khu~ch ~i lKD s~ lAm cho cOngtActa nAng N tac dOng. D¢ng co sl!i dUQc dong vAo ngu6n clI:p theo chi~u nAng bu6ng thang di l~n. Khi bu6ng thang di d€n tt1ng na.m, s~ tac dOng l~n cAm bi€n 5F, lam cho tin hi~u 1'a cua 5F .co muc lOgic "0". Tin hi~u ddu 1'a cua phdn tti 5V co muc lOgic "P chuy4n sang mlic lOgic "0". Tin hi~u 1'a cua 6H co muc lOgic "0\ dn hi~u 1'a cua 6V co muc lOgic "0", cO;ngtActo N milt di~n, dOng co ngi1ng quay, bu6ng thang dilng dung {J tt'ing nAm.
Mu6n hl;l bu6ng thang xu6ng tdng mOt, iln nut t1n lGT, tin hi~u ra- cua phlin ttt "HO';'C" lH co muc 16gic "1" dua vao pht1n til "vA" IV. Ba dau vao con ll;li cua IV d~u
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co muc lOgic np n@n diu 1'R CUR IV co mac lOgic np, cu¢n dAy cOngtl1ctd H co di~n dong di~n cho dQng cd thea chi~u quay hf,l bu6ng thang.
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