Generator yuritmasi.
1- elektrodvigatel; 2- mufta; 3- qiya tishli silindrik g’ildirakli reduktor;
4- zanjir; 5-generator
,, Generator yuritmasi “ loyihasining xisoboti:
Variant №
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Pb , kVt
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nb , min-1
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Db , mm
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11
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4
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175
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I. Elektrodvigatel tanlash va yuritmaning kinematic xisobi.
1. Elektrodvigateldan talab qilinadigan quvvat:
Pt= =4.4 kVt
ηum – yuritmaning umumiy foydali ish koeffitsienti
η1=0.97 η2=0.99 η3=0.96 ηum= η1·η3·η3 ηum=0.9
Pt= Pt= Pt=4.4 kVt
Jadvaldan quvvati Pdv=5.5 kVt; sinxron aylanishlar soni ns=1500 min-1; markasi 4A100L2 bo’lgan elektrodvigatel tanlaymiz. Sirpainish koeffitsienti S=3.7%
Elektrodvigatelning nominal aylanishlar soni ndv=ns·(1-s) ndv=1500·(1-0.037)
ndv=1445 min-1
2. Yuritmaning umumiy uzatishlar nisbati
ium= ium= ium=8.3
ium= izan· ured itas=4.5 deb qabul qilamiz. ured= ured= ured= 2.456
standart bo’yicha ured= 8.3 deb qabul qilamiz.
Shunda:
Izan= itas= izan=3.3 izan= 3.3 deb qabul qilamiz.
3. Yuritma vallaridagi quvvat, aylanishlar chastotasi, burchak tezligi va burovchi momentlarni aniqlash.
a) birinchi val
P1= Pt P1= 5.5 kVt ; n1= ndv n1= 1445 min-1 ω1= ω1= 151.3 sek-1
T1= 9550· T1= 9550· T1= 36.3 N·m
b) ikkinchi val
P2= P1·η1·η2 P2= 5.5·0.96·0.992 P2= 5.2 kVt
n2= n2= n2= 578 min-1
ω2= ω2= ω2=60.52 sek-1
T2= 9550· T2= 9550· T2= 85.91 N·m
d) uchinchi val
P3= P2·η2·η3 P3= 5.2·0.96·0.99 P3= 4.9 kVt
n3= n3= n3= 175 min-1
ω3= ω3= ω3= 18.3 sek-1
T3= 9550· T3= 9550· T3= 267.4 N·m
II. Reduktor tishli g’ildiraklarining xisobi
1. Shesternya va tishli g;ildirak uchun material tanlab, ular uchun ruxsat etilgan kuchlanishlarni aniqlaymiz.
3.3- jadvaldan o’rtacha mexanik xarakteristikali material tanlaymiz. Shesternya uchun HB1= 230, tishli g’ildirak uchun HB2= 200 bo’lgan Po’lat 45 materialini tanlaymiz. Termik ishlovi- yaxshilash.
Ruxsat etilgan kontakt kuchlanish:
σH=σHlimb·
σ1- sikllarning asosiy sonidagi kontakt mustahkamlik chegarasi, σHlimb= 2HB+70
KHL= 1 umirboqiylik koeffitsienti, (SH)= 1.1 xavfsizlik koeffitsienti,
Shesternya uchun, (σH1)= (σH1)= (σH1)= 481.818 MPa
Tishli g’ildirak uchun (σH2)= (σH2)= (σH2)= 409 MPa
Shunda to’g’ri tishli g’ildirak uchun ruxsat etilgan xisobiy kontakt kuchlanish,
(σH)= (σH2) (σH)= 409 MPa
2. Tishlarning faol sirtlari kontakt mustaxkamligi shartidan o’qlararo masofani hisoblaymiz,
aw= Ka(u+1)· aw= 43(2.5+1)·
aw=111.8 mm
Ka= 43 u= ured u= 2.5 KH𝛃= 1.25 𝟁ba= 0.25 T2= 85.9 N·m
Standart bo’yicha aw= 100 mm deb qabul qilamiz.
3. Normal modulni aniqlaymiz,
mn= (0.01∶0.02)·aw mn= (0.01∶0.02)·100 mn= 1∶2 mm
Standart bo’yicha mn= 2 mm deb qabul qilamiz.
4. Shesternya va tishli g’ildirak tishlari sonini aniqlaymiz.
Z1= 2· z1= 2· Z1= 28 Z1= 28 deb qabul qilamiz.
Z2=Z1·ired=28·22.5=70
Bu yerda Z2=70 deb olamiz.
5. Shesternya va tishli g’ildiraklarning asosiy o’lchamlari:
Qiyalik burchagi
Bo’luvchi diametrlari,
d1=57.4 d2=143
Tekshiruv: aw= aw= aw= 100=100 mm
Tishlar cho’qqisining diametrlari,
da1= d1+2·mn da1= 57+2·2 da1= 61 mm
da2= d2+2·mn da2= 143+2·2 da2= 147 mm
Tishli g’ildirak eni,
b2= ψ ba·aw b2= 0.4·100 b2= 40 mm
Shesternyaning eni,
b2= b2+5 b1= 45 mm
Shesternya eni koeffitsientini diametr bo’yicha aniqlaymiz,
𝟁bd= 𝟁bd= 𝟁bd= 0.789
Tishli g’ildiraklarning aylana tezligini aniqlaymiz,
ν= ω2· ν= 60.5· ν= 3.063 m/s
ν= 3 m/s da to’g’ri tishli g’ildiraklar aniqlik darajasini 8 deb qabul qilamiz.
6. Yuklanish koeffitsienti
KH= KH𝛃·KHα·KHʋ
KHα= 1 yuklamaning tishlararo taqsimlanishini hisobga oluvchi koeffitsienti
KH𝛃= 1.02 tishli g’ildirak gardishi bo’yicha yuklamaning notekis taqsimlanishini hisobga oluvchi koeffitsient,
KHʋ= 1.05 dinamik koeffitsient, deb qabul qilamiz.
KH= 1.02·1·1.05 KH= 1.071
7. Kontakt kuchlanishni quyidagi formula bo’yicha tekshiramiz:
σH= σH= σH= 686.2 MPa
8. Tishli ilashmaga tasir etuvchi kushlar:
Aylana kuch,
Ft= 2· Ft= 2· Ft= 3014 N
Radial kuch,
α= 20° tgα= 0.364 Fr= Ft·tgα Fr= 3014·0.364 Fr= 1097.1 N
9. Tishlarni egilishdagi kuchlanish bo’yicha mustahkamlikka tekshiramiz:
σF= ≤ (σF)
KF= KF𝛃·KFʋ - yuklanish koeffitsienti, KF𝛃= 1.08 – tish uzunligi bo’yicha yuklamaning notrkis taqsimlanishini hisobga oluvchi koeffitsient, KFʋ= 1.25 – yuklamaning dinamik tasirini xisobga oluvchi koeffitsient.
Shunda, KF= 1.08·1.25 KF= 1.35
YF - tish shaklini xisobga oluvchi koeffitsient ГОСТ 21354-75.
Shesternyaniki, Zʋ1= Z1 Zʋ1= 46 YF1= 4.09
Tishli g’ildirakniki, Zʋ2= Z2 Zʋ2= 115 YF2= 3.61
Ruxsat etilgan kuchlanish, (σF)= (SF)= 1.75 -xavfsizlik koeffitsienti,
σFlimb -tsikllarning asosiy soniga mos keluvchi mustahkamlik chegarasi.
Shesterbya uchun,
σ1Flimb= 1.8·HB1 σ1Flimb= 1.8·230 σ1Flimb= 414 MPa
Tishli g’ildirak uchun,
σ2Flimb= 1.8·HB12 σ2Flimb= 1.8·200 σ2Flimb= 360 MPa.
Shunda ruxsat etilgan kuchlanish quyidagicha:
Shesternya uchun,
(σF1)= (σF1)= 236.571 MPa
Tishli g’ildirak uchun,
(σF2)= (σF2)= 205.714 MPa
Quyidagi munosabatni , yani shesterbya va tishli g’ildirak uchun ruxsat etilgan kuchlanishni ular tishlarining shakliga nisbatini xisoblaymiz:
Shesternya uchun, = 60.659 MPa,
Tishli g’ildirak uchun, = 56.983 MPa.
Tishli g’ildirak tishining mustahkamligini tekshiramiz:
σF2=
σF2= σF2= 183.1 MPa
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