tính chọn xilanh cắt

Sheet1Thit k h thng thy lc vi cc s liu cho trc:Ti trng2000kgTrng lngkgVn tc cng tc40mm/sVn tc chy khng60mm/phPittong t thng ng, hng cng tc t di lniu khin tc bng van servo1. chn cc phn t thy lc*Xilanh ti trng*van servo*lc cao p*ng h o p*van trn*bm bnh rng*van cn2.phng trnh cn bng lc ca cm xilanh to ti trng

hnh trnh cng tc:p1*A1 = p2*A2 + Ft + Fmsc + Fmsp + G + FqtTrong :p1 - p sut du bung cng tcp2 - p sut du bung chy koA1 - din tch bung cng tcA1=3.14*D*D/4=19.625cm2A2 - din tch piston bung chy koA2=3.14*(D*D-d*d)/4=14.71875cm2Ft - ti trng cng tc Ft=2000kgG - trng lng ca khi lng mG=0.5kgFmsp - lc ma st ca pistion v xilanhFmsp=m*N12.56kgm=0.1(i vi cp vl xilanh l thp v vng gng bng gang)N - lc ca cc vng gng tc ng ln xilanh,N=3.14*D*b*(p2+pk) + 3.14*D*b*(z-1)*pk=125.6kgChn D=5cmb rng mi vng gng b=1cmp sut bung mang cn piston p2=5kg/cm2s vng gng z=3vngp sut tip xc ban u gia vng gng v xilanh pk=1kg/cm2Fmsc - lc ma st gia cn piston v vng chn khtFmsc= 0.15*f*3.14*d*b*p2=36.796875kgh s ma st cn - vng chn f=0.5*D=2.5ng knh cn piston d= 0.5*D=2.5cmchiu di tip xc ca vng chn vi cn b=d=2.5cmp sut tc dng vo vng chn chnh l p2=5kg/cm20.15 l h s tnh n s gim p theo chiu di vng chnFmst - lc ma st gia khi lng m v bc trt, lc ny c th b quaFqt - lc qun tnhFqt=G*v/g/t0=0.0203873598kggia tc trng trng, g=9.81m/s2G=0.5kgv=40mm/sthi gian qu ca piston n ch xc lp, chn t0=0.1sThay cc gi tr vo ta c p1=108.2023445788kg/cm2chn p1=118.2023445788kg/cm22. Phng trnh lu lng hnh trnh cng tcQ1=vct*D*D*3.14/4=78500mm3/s4.71l/ph4710cm3/phQ1 - lu lng cn cung cpvct - vn tc cng tc,40mm/s3. tnh chn cc thng s bmlu lng bm Qb=Q1=4.71l/php sut bm pb=p1=p0=118.2023445788kg/cm2Cng sut bm Nb=pb*Qb/6120.9096945147KW

Cng sut ng c in dn ng bm Ndc=Nb/hb/hd=1.0615491156KW

hb - hiu sut bm, chn hb=0.87hd - hiu sut truyn ng t c qua bm, chn hd= 0.985(theo gio trnh Chi tit my 2 - Ng Trng Hip)4. Tnh ton ng dnLu lng chy qua ng Q=3.14*d*d*v/4Suy ra d=4.6*(Q/v)^(1/2)Q (l/ph)d - ng knh trong ca ng (mm)v - vn tc chy qua ng (m/s)i vi ng nn, chn v =6m/si vi ng ht, chn v =1.5m/si vi ng x, chn v =1.5m/sSuy ra d tng ngd nn=4.0756103837mmd ht=8.1512207675mmd x=8.1512207675mmChn dy du ISO 21 9 theo hnh v sauhay cn gi l dy du 3/8

Sheet2

Sheet3