Lentali konveyer yuritmasi. 1- elektrodvigatel; 2- ponasimon tasma; 3- to’g’ri tishli silindrik g’ildirakli reduktor

Lentali konveyer yuritmasi.
1- elektrodvigatel; 2- ponasimon tasma; 3- to’g’ri tishli silindrik g’ildirakli reduktor;
4- mufta; 5-lentali konveyer barabani.

,, Lentali konveyer yuritmasi “ loyihasining xisoboti:

Variant №	Pb , kVt	nb , min^-1	Db , mm
	3,5	90	300

I. Elektrodvigatel tanlash va yuritmaning kinematic xisobi.
1. Elektrodvigateldan talab qilinadigan quvvat:
P_t= kVt
η_um – yuritmaning umumiy foydali ish koeffitsienti
η₁=0.96 η₂=0.98 η₃=0.99 η_um= η₁·η₂·η₃³ η_um=0.912
P_t= P_t= P_t=3.834 kVt
Jadvaldan quvvati P_dv=4 kVt; sinxron aylanishlar soni n_s=1000 min^-1; markasi 4A112MB6 bo’lgan elektrodvigatel tanlaymiz. Sirpainish koeffitsienti S=5.1%
Elektrodvigatelning nominal aylanishlar soni n_dv=n_s·(1-s) n_dv=1000·(1-0.047) n_dv=995 min^-1
2. Yuritmaning umumiy uzatishlar nisbati
i_um= i_um= i_um=11.054
i_um= i_tas· u_red i_tas=4.5 deb qabul qilamiz. u_red= u_red= u_red= 2.456
standart bo’yicha u_red= 2.5 deb qabul qilamiz.
Shunda:
i_tas= i_tas= i_tas=4.422 i_tas= 4.5 deb qabul qilamiz.
i_{um 1}= i_tas· u_red i_{um 1}=4.5·2.5 i_{um 1}=11.25
3. Uzatishlar nisbatining farqi
Δi= ·100 Δi= -1.738 -1.738 ≤ 3% shart bajarilmoqda.
4. Yuritma vallaridagi quvvat, aylanishlar chastotasi, burchak tezligi va burovchi momentlarni aniqlash.
a) birinchi val
P₁= P_t P₁= 4 kVt ; n₁= n_dv n₁= 995 min^-1 ω₁= ω₁= 104.1 sek^-1
T₁= 9550· T₁= 9550· T₁= 38.4 N·m
b) ikkinchi val
P₂= P₁·η₁·η₂ P₂= 4·0.96·0.98 P₂= 3.8 kVt
n₂= n₂= n2= 221 min-1
ω₂= ω₂= ω₂=23.1 sek^-1
T₂= 9550· T₂= 9550· T₂= 162.5 N·m
d) uchinchi val
P₃= P₂·η₂·η₃ P₃= 3.8·0.98·0.99 P₃= 3.7 kVt
n₃= n₃= n₃= 88.4 min^-1
ω₃= ω₃= ω₃= 23.1 sek^-1
T₃= 9550· T₃= 9550· T₃= 394.3 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=σ_Hlimb·
σ₁- sikllarning asosiy sonidagi kontakt mustahkamlik chegarasi, σ_Hlimb= 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)= 427.273 MPa
Shunda to’g’ri tishli g’ildirak uchun ruxsat etilgan xisobiy kontakt kuchlanish,
(σH)= (σH2) (σH)= 427.273 MPa
2. Tishlarning faol sirtlari kontakt mustaxkamligi shartidan o’qlararo masofani hisoblaymiz,

aw= Ka(u+1)· aw= 49.5(2.5+1)·

aw=174.4 mm
Ka= 49.5 u= u_red u= 4.5 KH𝛃= 1.15 𝟁ba= 0.25 T₃= 372 N·m
Standart bo’yicha aw= 200 mm deb qabul qilamiz.
3. Normal modulni aniqlaymiz,
m_n= (0.01∶0.02)·aw m_n= (0.01∶0.02)·200 m_n= 2∶4 mm
Standart bo’yicha m_n= 2.5 mm deb qabul qilamiz.
4. Shesternya va tishli g’ildirak tishlari sonini aniqlaymiz.
Z₁= 2· z₁= 2· Z₁= 45.7 Z₁= 46 deb qabul qilamiz.

Buyerda Z2=116 deb Olamiz.
5. Shesternya va tishli g’ildiraklarning asosiy o’lchamlari:
Bo’luvchi diametrlari,
d1=123 d2=305
Tekshiruv: aw= aw= aw= 213.5≈200 mm
Tishlar cho’qqisining diametrlari,
da₁= d₁+2·mn da₁= 123+2·2.5 da₁= 128 mm
da₂= d₂+2·mn da₂= 305+2·2.5 da₂= 310 mm
Tishli g’ildirak eni,
b₂= ψ ba·aw b₂= 0.25·200 b₂= 50 mm
Shesternyaning eni,
b2= b₂+5 b₁= 55 mm
Shesternya eni koeffitsientini diametr bo’yicha aniqlaymiz,
𝟁bd= 𝟁bd= 𝟁bd= 0.447
Tishli g’ildiraklarning aylana tezligini aniqlaymiz,
ν= ω_2· ν= 24.9_· 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= 395.67 MPa
σH˂(σH) 395.67 ˂ 427.273 MPa
8. Tishli ilashmaga tasir etuvchi kushlar:
Aylana kuch,
Ft= 2· Ft= 2· Ft= 1242 N
Radial kuch,
α= 20° tgα= 0.364 Fr= Ft·tgα Fr= 3423.9·0.364 Fr= 882.299 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= 67.315 MPa