1- Thanh dAn hu6ng; 2- G(J1IgkbntnzVt; 3-Dai truyfn;" -He tMR8d~8bdnh vit-trliC vit; 5 - Ntm.
§3.2. PHAN LOJ),I vA eAe THONG SO Ki THU;'T
eo BAN eUA THANG MAy
Tuy thu¢e V3a ehuc n8.11&', thang may co thg phAn laf,li thea cae nh6m sau 1 - Thang may eha DgI1bi trong cae nhA cae, ~ng.
2 - Thang may dung trang cae b~nh vi~n.
3 - Thang may cM hang co ngttbi di~u khien. 4 - Thang may dung trang nha An va thu vi~n.
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PhAn lOI;li thea tl'Qng tai :
1 - Thang may la~ nM Q < 160kG.
2 - Thang may trung blnh Q = 500 +- 2000 kG. 3 - Thang ma.y ial:li IOn Q > 2000kG.
PhAn lalili thea t6c d¢ di chuy~n :
1 - Thang may chlilY ch$.m v = 0,5mJs.
2 - Thang may t6c dti trung blnh v = 0,75 + 1,5m/s. 3 - Thang may caa t6c v = 2,5 + 5mJs.
§3.3. TINH CHQN CCNG SUAT DONG CO TRUYEN DONG THANG MAy DONG CO TRUYEN DONG THANG MAy
D~ dnh chc;m d11QC cOng su!t dQng co truy~n d¢ng tbang may clin cO cac di~u ki(!n
vA tham s6 sau :
- So d6 dOng hQc cua thang may - T6c d¢ vA gia t6c Ion nhl'lt cha phep
- TrQng tAi
- Tr~mg 111c;fng pu6ng thang.
COng su!t tlnh cua dOng 00 khi nAng tai khOng dung d6i tI"Qng d11QC dnh thea cOng thuc sau :
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Trang d6 Gbl - kh6i hlQng bu6ng thang [kg] G - kh6i hlQng bAng, [kg]
v - t6c dQ nAng, [mls)
g - gia t6c tl'Qng tr11bng, [m/s2]
rz - hiQ:u suAt cUa CO" Cl1u nAng (0,5 + 0,8).
(3-1)
Khi c6 d6i trQng, cOng su!t dnh cUa dOng Cd 11k nAng tl\i dl1QC dnh thea bi~u thuc sau :
Pen = {[G + GbtJi - Gdt.rz}vkg.1O-3, [kW]. (3-2) VA khi hl;l tAi
(3-3)
Trang d6 : Pen - cOng su!t dnh cua d¢ng 00 khi nAng co dung d6i trQng P eh - cOng sul'lt dnh cua dQng 00 khi hl;l co dung d6i trQng Gdt - kh6i 111Qng cua d6i trQng, [kg]
k - ~ Oil tlnh Mn rna sat gifta thanh WIn bUbng va d& tn,mg (k = 1,15 + 1,3). Kh6i 111c;mg cua d6i trQng dl1QC dnh thea bi~u thuc sau dAy:
Gdt = Ghl + aG, [kg]. (3-4)
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Phlin 16:n cac thang mAy eM khach chI v$,n hAnh dl1y titi trvng nhung gtb can di~m,
thOi gian -dm l~i luOn lam vi~c non tAi ; cho n€m d6i vdi thang may cha kMch n~n ChQD M a6 a ::= 0,35 -I- 0,4.
D6i v{Ji thang may chc'J hllng, khi nling thllbng IS. diiy tl).i vii khi hl;l thu:bng Iii. khOng
tAi, nlm chc;m a = 0,5.
D\ia t~n hai bi~u thuc (3-2) va. (3-3) c6 the xAy dl,1'ng dllt;JC biell dfi ph\! tAi vA chc;m ad bl) cOng sullt cua dOng co thea s6 tay tra CUll.
Mudn xAy d\ing bi~u d6 ph1,l tAi chtnh xac, din phAi dnh d~n thbi gian rna may, thbi gian hl1m, thai gian dong, rna cua va 86 IAn dling cua bu6ng thang khi chuyen dl;lng.
ThOng s6 tllCfng d6i M tfnh toan cae thai gian trlln dllQ'C dua ra trong bAng 3-1. Thbi gian ra, vAo bu6ng thang dllQC dnh gl1n dung ls/l ngubL 86 lAn dung (dnh thea XBC su.!It) eua bu6ng thang co the dm thea cae dubng cong tr€!n hlnh 3-3.
T6e dO di ehuyen (m/s) 0,5 0,75 1,0 1,5 2,5 3,5 18 16 14 12 10 8 6 4 2 V V Bimg 3-1
Thbi gian rna may T6ng thbi gian cOn l~i (8)
vii hl1rn may v(1i khoang
Bu6ng thang Bu6ng thang Bu6ng thang each giua ella Ung (s)
cd ci'ta r¢ng co etta r¢ng e6 ella rOng 3,6 met .. 7,2 met duili BOOmm dulli BOOrnm dulli 1000mrn
(md bAng tay) (meJ t~ dQng) (rna tV' dOng)
, 1,6 1,6 12,0 7,0 - 1,6 1,6 12,0 7,0 - 1,8 1,8 13,0 7,0 6,3 1,8 1,8 - 7,2 6,3 2,8 2,0 - - 6,5 3,2 2,5 - - 7,0 --- E 21n uai / ' .-- E-1 ngui / " ..------ .<,. r" E 13ng yo; f;:: / E lOng 0/ :----.-- E 5nau '; 5 10 14 18 22 26 30 34 38 42 46 50 m,
Hlnh 3-3. Dl1dng cong de x.IIc dinh ~ illn dung (thoo xAc suJll) Clla bu6ng thang. md - sO lIin dung; rn,. - s6 tA:ng ; E - s6 ngtlOi lrung bu6ng thang.