Mashinasozlik texnologiyasi

O’ZBEKISTON RESPUBLIKASI OLIY VA O’RTA

MAXSUS TA’LIM VAZIRLIGI

ISLOM KARIMOV NOMIDAGI

TOSHKENT DAVLAT TEXNIKA

UNIVERSITETI

“MASHINASOZLIK TEXNOLOGIYASI” FAKULTETI

KURS ISH

MAVZU: Lentali konveyer yuritmasini loyihalash.

Guruh: 53A-18MT

Bajardi: Bakirov X.

Qabul qildi: Ergashev B.

Toshkent-2021



Lentali konveyer yuritmasi.

1- elektrodvigatel; 2- yassi tasmali uzatma; 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
4	3,0	70	350

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=3.29 kVt

Jadvaldan quvvati P_dv=3.0 kVt; sinxron aylanishlar soni n_s=1000 min^-1; sirpanish s=5.1%; markasi 112MA6 bo’lgan elektrodvigatel tanlaymiz.

Elektrodvigatelning nominal aylanishlar soni n_dv=n_s·(1-s) n_dv=1000·(1-0.047) n_dv=953 min^-1

2. Yuritmaning umumiy uzatishlar nisbati

i_um= i_um= i_um=13.6

i_um= i_tas· u_red i_tas=3 deb qabul qilamiz. u_red= u_red= u_red= 4.53

standart bo’yicha u_red= 4.5 deb qabul qilamiz.

Shunda:

i_tas= i_tas= i_tas= 3.022 i_tas= 3 deb qabul qilamiz.

i_{um 1}= i_tas· u_red i_{um 1}=4.5·3 i_{um 1}=13.5

3. Uzatishlar nisbatining farqi

Δi= ·100 Δi= -0.0735 -0.0735 ≤ 3% shart bajarilmoqda.

4. Yuritma vallaridagi quvvat, aylanishlar chastotasi, burchak tezligi va burovchi momentlarni aniqlash.

a) birinchi val

P₁= P_t P₁= 3 kVt ; n₁= n_dv n₁= 953 min^-1 ω₁= ω₁= 99.747 sek^-1

T₁= 9550· T₁= 9550· T₁= 30.062 N·m

b) ikkinchi val

P₂= P₁·η₁·η₂ P₂= 3·0.96·0.98 P₂= 2.822 kVt

n₂= n₂= n2= 317.666 min-1

ω₂= ω₂= ω₂= 33.249 sek^-1

T₂= 9550· T₂= 9550· T₂= 84.837 N·m

d) uchinchi val

P₃= P₂·η₂·η₃ P₃= 2.822·0.98·0.99 P₃= 2.737 kVt

n₃= n₃= n₃= 70.592 min^-1

ω₃= ω₃= ω₃= 7.388 sek^-1

T₃= 9550· T₃= 9550· T₃= 370.273 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(4.5+1)·

aw= 210.272 mm

Ka= 49.5 u= u_red u= 4.5 KH𝛃= 1.15 𝟁ba= 0.25 T₃= 370.273 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= 3.5 mm deb qabul qilamiz.

4. Shesternya va tishli g’ildirak tishlari sonini aniqlaymiz.

Z₁= 2· z₁= 2· Z₁= 20.799 Z₁= 20 deb qabul qilamiz.

Shunda, Z₂= Z₁·u Z₂= 20·4.5 Z₂= 90 Z₂= 94 deb qabul qilamiz.

5. Shesternya va tishli g’ildiraklarning asosiy o’lchamlari:

Bo’luvchi diametrlari,

d₁= mn·Z₁ d₁= 3.5·20 d₁= 70 mm, d₂= mn·Z₂ d₂= 3.5·94 d₂= 329 mm

Tekshiruv: aw= aw= aw= 199.5≈200 mm

Tishlar cho’qqisining diametrlari,

da₁= d₁+2·mn da₁= 70+2·3.5 da₁= 77 mm

da₂= d₂+2·mn da₂= 329+2·3.5 da₂= 336 mm

Tishli g’ildirak eni,

b₂= ba·aw b₂= 0.25·200 b₂= 50 mm

Shesternyaning eni,

b₁= b₂+5 b₁= 55 mm

Shesternya eni koeffitsientini diametr bo’yicha aniqlaymiz,

𝟁bd= 𝟁bd= 𝟁bd= 0.786

Tishli g’ildiraklarning aylana tezligini aniqlaymiz,

ν= ω_2· ν= 33.249_· ν= 1.164 m/s

ν= 1.16 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= 2423.9 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 notekis 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= 20 YF₁= 4.09

Tishli g’ildirakniki, Zʋ₂= Z₂ Zʋ₂= 94 YF₂= 3.61

Ruxsat etilgan kuchlanish, (σF)= (SF)= 1.75 -xavfsizlik koeffitsienti,

σFlimb -tsikllarning asosiy soniga mos keluvchi mustahkamlik chegarasi.

Shesternya 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

σF2 ≤ (σF2)

Mustahkamlik sharti bajarilmoqda.