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ĐHBK Tp.HCMTRANSCRIPT
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Trng HBK TPHCM N CHI TIT MY - 2011
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LI NI U
t nc ta ang trn pht trin, do khoa hc k thut ng mt vai tr quan trng
trong cng cuc cng nghip ha, hin i ha t nc. Vic p dng khoa hc k thut chnh l
lm tng nng sut lao ng, thay th sc lao ng ca ngi lao ng mt cch c hiu qu nht,
bo m an ton cho ngi lao ng trong qu trnh lm vic. to nn tng tt cho bc pht
trin trong tng lai, chng ta cn u t, nghin cu, gio dc, pht trin khoa hc k thut mt
cch nghim tc ngay t trong cc trng i hc.
n mn hc Chi Tit My l mt mn hc gip sinh vin ngnh Ch To My c bc
i chp chng, lm quen vi cng vic thit k m mi ngi k s c kh s gn cuc i mnh
vo . Hc tt mn hc ny s gip cho sinh vin mng tng ra c cng vic tng lai, qua
c cch nhn ng n hn v con ng hc tp ng thi tng thm lng nhit huyt, yu
ngh cho mi sinh vin. Khng nhng th qu trnh thc hin n s l th thch thc s i
vi nhng k nng m sinh vin c hc t nhng nm trc nh v c kh, k nng s dng
phn mm: Autocad, Autocad Mechanical, Autodesk Inventor cng vi nhng kin thc trong
nhng mn hc nn tng: Nguyn l my, Chi tit my, Dung sai v K thut o
Trong qu trnh thc hin n, chng em nhn c s ch dn rt tn tnh ca thy
PGS.TS Nguyn Hu Lc cng cc qu thy c khc trong Khoa. S gip ca cc thy c l
ngun ng lc ln lao c v tinh thn cho chng em trn con ng hc tp, rn luyn y gian
lao vt v.
Do y l bn thit k k thut u tin m chng em thc hin nn chc chn s mc phi
nhng thiu xt, sai lm. Em rt mong nhn c s gp chn thnh t pha cc thy c. Em xin
chn thnh cm n.
Sinh vin thc hin
Trn ng Khu
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Trng HBK TPHCM N CHI TIT MY - 2011
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Mc lc LI NI U ................................................................................................................................. 2
Phn mt: Tnh ton chn ng c v t s truyn: ....................................................................... 4
1.1. Tnh ton chn ng c: ......................................................................................................... 4
1.2. Phn phi t s truyn v tnh ton ng hc h dn ng xch ti:.......................................... 5
Phn hai: Tnh ton b truyn ai: ................................................................................................. 7
2.1. Thng s ban u: .................................................................................................................. 7
2.2. Tnh ton thit k b truyn ai: ............................................................................................. 7
Phn ba:Thit k b truyn trong hp gim tc ............................................................................. 9
3.1 Tnh ton b truyn cp nhanh: .......................................................................................... 9
3.2 Tnh ton b truyn cp chm:.......................................................................................... 15
Phn bn: Kim tra bi trn ngm du........................................................................................ 23
Phn nm:Thit k trc ................................................................................................................ 24
4.1 Thit k trc 1:....................................................................................................................... 24
4.2 Thit k trc 2 ........................................................................................................................ 28
4.3 Thit k trc 3:....................................................................................................................... 32
Phn su: Kim nghim then ........................................................................................................ 35
Phn by: Chn ln v ni trc.................................................................................................. 39
I Trc u vo 1:....................................................................................................................... 39
II Trc trung gian 2: .................................................................................................................. 41
III Trc u ra 3:....................................................................................................................... 43
IV Chn ni trc vng n hi: ................................................................................................. 46
Phn tm: Thit k v hp v cc chi tit ph .............................................................................. 47
Phn chn: Chn du bi trn v dung sai lp ghp .................................................................... 50
TI LIU THAM KHO ............................................................................................................. 53
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Trng HBK TPHCM N CHI TIT MY - 2011
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Phn mt:
TNH TON CHN NG C,PHN PHI T S TRUYN.
1.1. Tnh ton chn ng c:
1.1.1. S liu ban u: H thng truyn ng bng ti lm vic c cc thng s sau:
- Lc vng trn bng ti: F = 2500 N
- Vn tc bng ti: v = 1,25 m/s
- ng knh tng dn: D = 400 mm
- Thi gian phc v: L = 7 nm
H thng truyn ng bng ti quay 1 chiu, lm vic 2 ca, ti va p nh (1 nm lm vic
280 ngy, 1 ca lm vic 8 gi).
1.1.2. Xc nh cng sut cn thit ca ng c:
Cng sut trn trc ng c in c xc nh theo cng thc:
tct
PP
(theo (2.8))
Trong : Pct - cng sut cn thit trn trc ng c, kW;
Pt - cng sut tnh ton trn trc my cng tc, kW;
- hiu sut truyn ng.
Hiu sut truyn ng:
3 30, 99 0,99 0,97 0,96 0,95 0,85K ol brc brt d (theo (2.9))
vi: K - hiu sut ni trc n hi ; ol - hiu sut 1 cp ln; brc - hiu sut 1 cp bnh rng
cn; brt - hiu sut 1 cp bnh rng nghing; d - hiu sut b truyn ai, tr s ca cc hiu sut
trn tra theo bng 2.3.
H thng truyn ng bng ti lm vic vi s ti trng nh sau:
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Theo (2.12) v (2.13), cng sut lm vic trn trc my cng tc: 2 2 2 2
1 21 2
1 2
0,83..12 .60. 2500.1,25. . 2,69
1000 1000 12 60t td
T T T Tt tF v T T T TP P kW
t t
Khi : 2, 69 3,1650,85
tct
PP
kW.
1.1.3. Xc nh s b s vng quay ng b ca ng c:
Theo (2.17) , s vng quay ca trc my cng tc:
= 60000 vD= 60000. 1, 25
.400= 59,68 vng/pht
trong : v - vn tc bng ti, v = 1,25 m/s;
D ng knh tang dn, D = 400 mm.
T bng 2.4 , ta chn t s truyn ca hp gim tc bnh rng cn - tr hai cp 12hu ;
4du , do s vng quay s b ca ng c theo (2.18) nh sau:
12 4 59, 68 2864,64sb lv tn n n vng/pht
Chn s vng quay ng b ca ng c 3000dbn vng/pht.
1.1.4. Chn ng c:
Theo bng P1.3 vi 3,165ctP kW v 3000dbn vg/ph ta dng ng c DK51-2 c
4,5dcP kW, 2900dcn vng/pht.
1.2. Phn phi t s truyn v tnh ton ng hc h dn ng xch ti: 1.2.1. Phn phi t s truyn:
Chn loi hp gim tc bnh rng cn tr 2 cp:
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T s truyn ut ca h dn ng: 2900 48,659,68l
dct
v
nun
(theo (3.23))
trong : dcn - s vng quay ca ng c chn, 2900dcn vng/pht;
lvn - s vng quay ca trc my cng tc, 59,68lvn vng/pht.
Phn phi t s truyn ca h dn ng: 59,68t h xu u u (theo (3.24) )
Suy ra: 4 248,6 1
d
thu u
u
Da vo hnh 3.20 , ta chn t s truyn cp nhanh ca hp gim tc 1 4u v t s truyn
cp chm ca hp gim tc 2 3u .
Tnh li gi tr ca du theo tu trong hp gim tc: 1 2
48, 63
44
td u u
uu
Vy ta chn 4du
1.2.2. Xc nh cng sut, mmen v s vng quay trn cc trc:
32,69 2, 720,99
lv
K
PP
kW; 322,72 2,86
. 0,96 0,99brt ol
PP
kW
21
2, 68 2,98. 0,97 0,99brc ol
PP
kW; 1 2,98 3,17. 0,95 0,99dc d ol
PP
kW
2900dcn (v/p) ; 12900 725
4dc
d
nnu
(v/p); 121
725 181,254
nnu
(v/p)
23
2
181, 25 60, 423
nnu
(v/p)
6 3,179,55 10 10439,142900dc
T Nmm ;
61
2,989,55 10 39253,79725
T Nmm
62
2,869,55 10 150692, 41181, 25
T Nmm ;
63
2,729,55 10 429923,8760, 42
T Nmm
BNG PHN PHI T S TRUYN
Trc
Thng s
ng c I II III
Cng sut P, kW 3,17 2,98 2,86 2,72
T s truyn u 4 4 3
S vng quay n, vng/pht 2900 725 181,25 60,42
Mmen xon T, Nmm 10439,14 39253,79 150692,41 429923,87
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Phn hai:
TNH TON B TRUYN AI 2.1. Thng s ban u: - Cng sut truyn n: 3,17P kW - S vng quay: 2900dcn vng/pht
- T s truyn: 4u
2.2. Tnh ton thit k b truyn ai: Bc 1. Chn tit din ai:
Vi cng sut v s vng quay nh trn ta chn ai tit din A (hnh 4.1).
Bc 2. Chn cc thng s c bn ca b truyn ai:
Theo bng 4.13 chn ng knh bnh ai nh 1 125d mm.
Vn tc ai 1 1 .125.2900 18,9860000 60000
d nv m/s ( nh hn vn tc cho php max 25v
m/s)
Theo cng thc 4.2, vi 0,02 , ng knh bnh ai ln
2 1(1 ) 4.125.(1 0,02) 490d ud mm
Theo bng 4.26 ng knh tiu chun 2 500d mm
Nh vy t s truyn thc t:
2
1
500 4,08(1 ) 125.(1 0,02)tdu
d
V sai lch
( ) (4,08 4) .100% 2% 4%4
tu uuu
Theo bng 4.14 chn s b khong cch trc 20,95. 0,95.500 475a d mm, theo cng
thc 4.4 chiu di ai: 2 2
2 11 2
( ) (500 125)2 0,5 ( ) 2.475 0,5 (125 500) 2006( )4 4.475
d dl a d d mma
Theo bng 4.13 chn chiu di ai tiu chun: 2000l mm.
Theo 4.15 nghim s vng chy ca ai trong 1s: 18,98 9,492
vil
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vi : 2000 0,5 (125 500) 1018, 25
2 1 500 125 187,52 2
d d
Theo 4.7 gc m 2 11 min57( ) 57.(500 125)180 180 135 120
471,87d d
a
Bc 3. Xc nh s ai: Theo cng thc 4.16
1
0
3,71.1,35 1,63[ ] 3,01.0,88.1,04.1,14.0,98
d
l u z
PKzP C C C C
Trong : Theo bng 4.7, 1,35dK Vi 1 135 ta chn 0,88C (bng 4.15)
Vi 0
2000 1,1761700
ll chn 1,04lC (bng 4.16)
Vi 4u ta chn 1,14uC (bng 4.17)
Vi 18,98v m/s, 1 125d mm, chn 0[ ] 3,01P kW (bng 4.19)
Vi 10
3,71 1, 23[ ] 3,01PP
ta chn 0,98zC (bng 4.18)
Ly 2z ai.
Chiu rng bnh ai, theo 4.17 v bng 4.21
( 1) 2 (2 1).15 2.10 35B z t e mm
ng knh ngoi ca bnh ai:
02 125 2.3,3 131,6ad d h mm
Bc 4. Xc nh lc cng ban u v lc tc dng ln trc:
Theo 4.19 1780. 780.3,71.1,35 37,83 154,7818,98.0,88.2
da v
PKF FvC z
N
Trong : 2 2. 0,105.18,98 37,83v mF q v N (bng 4.22)
Theo 4.21 lc tc dng ln trc :
10
1352 sin( ) 2.154,78.2.sin( ) 5722 2r
F F z
N
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Phn ba:
THIT K B TRUYN TRONG HP GIM TC
3.1 Tnh Ton B Truyn Cp Nhanh Cc thng s ban u
Cng sut u vo: 1 2,98P kW Moment xon: = 39253,79 S vng quay: = 725 / T s truyn: u = 4 Thi gian phc v: 7 nm Quay mt chiu, lm vic hai ca ( 1 nm lm vic 280 ngy, mt ca 8 gi) Ch ti: = , = 0.83
= 12 , = 60
1) Chn vt liu:
Ta chn vt liu cho cp bnh cn rng thng nh sau:
+ Bnh nh : Thp 45 ti ci thin t rn b mt HB = 270,
c 1b=850(MPa);
1ch=580(MPa).
+ Bnh ln : Thp 45 ti ci thin t rn b mt HB =255,
c 2b=750(MPa);
2450ch (MPa).
2) Xc nh ng sut cho php : Tnh s b ng sut un v ng sut tip xc cho php theo cc cng thc
6.1a v 6.1b ta c:
0lim.[ ] F HLH
H
Ks
;
0lim. .[ ] F FC FLF
F
K Ks
.
Trong : limoF ,
0limH : ln lt l ng sut un v ng sut tip xc cho php ng vi s chu
k c s, tr s ca chng c tra bng 6.2: lim 1,8oF HB v 0 lim 2 70H HB
Fs , Hs : ln lt l h s an ton khi tnh v un v tip xc tra bng 6.2 1, 75Fs v 1,1Hs
Khi :
1
0lim 2 220 70 610H (MPa)
1
0lim 1,8 270 486F ( MPa)
2
0lim 2 255 70 580H (MPa)
0lim 2 1,8 255 459F (MPa)
FcK : H s xt n nh hng t ti ,ly 1FcK (ti trong t mt pha)
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HLK , FLK : H s tui th, c xch nh theo cng thc 6.3 v 6.4:
HHOm
HLHE
NKN
;
FFOm
FLFE
NKN
y: Hm , Fm : Bc ca ng cong mi khi th v tip xc v un vi HB 350 ly:6; 6H Fm m FON , HON : S chu k thay i ng sut c s khi th v un v tip xc
+ FON = 4.106 vi tt c cc loi thp
+ 2,430HO HBN H
7
7
10.97,1
10.05,2
2
1
HO
HO
N
N
+ HEN , FEN : s chu k thay i ng sut tng ng V b truyn lm vic ch ti trng thay i nhiu bc nn theo cc cng thc 6.7 v 6.8
ta c:
260 . .
Hm
iHE i i
TN c n tT
; 60 . .Fm
iFE i i
TN c n tT
vi: c l s ln n khp trong mt vng quay ca bnh rng, c = 1
in , it : S vng quay v thi gian lm vic ch i
Ta c:
3 3 81 1
1 5N 60 1 725 31360 (1 0,83 ) 8, 77 10 N6 6HE HO
1 1HLK
3 3 82 2
1 5N 60 1 181, 25 31360 (1 0,83 ) 2,19 10 N6 6HE HO
2 1HLK
6 6 81 1
1 5N 60 1 725 31360 (1 0,83 ) 8, 77 10 N6 6FE FO
1 1FLK
6 6 82 2
1 5N 60 1 181, 25 31360 (1 0,83 ) 2,19 10 N6 6FE FO
2 1FLK
Nh vy:
1610 1 554,5
1,1H (MPa);
2
580 1 527,31,1H
(MPa)
Vi bnh cn rng thng ta c:
1 2min ; 527,3H H H MPa ;
1486 1 1 277,7
1,75FMPa ; 2
459 262,31,75F
MPa
ng sut qu ti cho php, theo cc cng thc 6.13 v 6.14 ta c:
max 2[ ] 2,8 2,8 450 1260 MPaH ch
1max 2[ ] 0,8 0,8 580 464 MPaF ch
2max 2[ ] 0,8 0,8 450 360 MPaF ch
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3) Xch nh chiu di cn ngoi: Theo cng thc 6.52a ta c:
12 32
.1.
(1 ). . .[ ] H
e Rbe be H
T kR k u
k k u
Trong : 0,5R dk k : H s ph thuc vo vt liu bnh rng v loi rng,vi truyn ng
bnh cn rng thng bng thp 100dk (MPa)1/3
130,5 100 50 MPaRk
u: T s truyn cp nhanh ca hp gim tc, u = 4
T1: Mmen xon trn trc dn ( T1 = 39253,79N.mm)
beK : H s chiu rng vnh rng, ly 0,285beK
HK : H s k n s phn b ti trng khng u trn chiu rng vnh rng tra
bng 6.21 vi : . 0, 285.4 0,662 2 0,285
be
be
K uK
, do trc lp trn a ta c: 1,15HK
Suy ra:
23
2
1,1550 4 1 120, 4(1 0, 285) 0,285 4 527
3925,3
3,79 eR mm
4) Xc nh cc thng s n khp : ng knh chia ngoi ca ca bnh cn ch ng c xc nh theo cng thc 6.52b:
131 2 2 2
. 2. 2 120, 4. 58,4(1 ). . .[ ] 1 4 1
H ee d
be be H
T K Rd K mmK K u u
Tra bng 6.22 ta c 1 16pz vi 1 1350 1,6 1,6 16 25,6pHB z z .
ng knh trung bnh v modun trung bnh ca bnh cn nh:
1 1(1 0,5 ). (1 0,5 0,285) 58,4 50,08m be ed K d mm
1
1
50,08 1,9625,6
mtm
dm mmz
Modun vng ngoi c xc nh theo cng thc 6.5:
1,96 2,291 0,5. 1 0,5 0, 285
tmte
be
mm mmK
Theo bng 6.8 ly gi tr tiu chun 2,5tem mm do :
(1 0,5. ) 2,5 (1 0,5 0,285) 2,13tm te bem m K mm
11
50,08 23,52,13
m
tm
dzm
ly 1 24z (rng)
2 1 1 4 24 96z u z rng.
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Do t s truyn thc t 211
96 424
zuz
Gc cn chia :
' ''11
2
24arctan arctan 14,04 14 210, 4896
ozz
' ''2 90 14, 04 75,96 75 57 36
o
Theo bng 6.20 vi 1 24z ta chn h s dch chnh u 1 0,39x ; 2 0,39x
ng knh trung bnh ca bnh nh: 1 1 . 24 2,13 51,12m tmd z m mm
Chiu di cn ngoi:
2 2 2 21 20,5. 0,5 2,5 24 96 123,69e teR m z z mm
5) Kim nghim rng v bn tip xc :
Theo cng thc 6.33 ta c:
21
21
2. . . 1. . [ ]0,85. . .
HH M H H
m
T K uZ Z Zb d u
Trong :
mz : h s k n c tnh vt liu ca bnh rng, theo bng 6.5 ta c 13274mz MPa
z :h s k n s trng khp ca rng ,c xc nh theo cng thc 4z
3
y l h s trng khp ngang, c tnh theo cng thc:
1 2
1 11,88 3, 2 cos( ) 1, 71z z
(vi 0 ); 4 1,71 0,8743e
z
Hz : H s k n hnh dng b mt tip xc,theo bng 6.12 ta c 1,76Hz
1T : Mmen xon trn trc dn 1 39253,79 T Nmm
HK : H s ti trng khi tnh ton v tip xc, c xc nh theo cng thc 6.61
. .H H H HVK K K K
y:
HK : H s k n s phn b ti trng khng u trn chiu rng vnh
rng 1,15HK
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HK : H s k n s tp trung ti trng khng u trn gia cc rng ly
1HK
HVK : H s xt n nh hng ca ti trng ng, tnh theo cng thc 6.63
1
1
. .1 2
H mHV
H H
v b dKT K K
Trong : 10.( 1). . mH H
d uv g vu
vi: 1. . 3,14 51,12 725 1,94 /60000 60000
md nv m s . Theo
bng 6.13 ta chn cp chnh xc b truyn l 8. H l tr s k n nh hng ca sai s n khp
,theo bng 6.15 vi dng rng thng th 0,006H . 0g l h s k n nh hng ca sai lch
bc rng ,theo bng 6.16 vi cp chnh xc mc lm vic m l 7 th 0 47g . Suy ra:
51,12 (4 1)0,006 47 1,94 4,374H
v
b : chiu rng vnh rng, . 0, 285 123,69 35, 25be eb K R ly 35b mm .
Vy 4,37 35 51,121 1,092 39253,79 1 1,15HV
K
Do 1,09 1,15 1 1, 25 HK .
Vi cc tr s va tm c ta c:
2
22 39253,79 1,25 4 1274 1,76 0,874. 480,77
0,85 35 51,12 4HMPa
Theo bng 6.1 th [ ] [ ] . . . H H sb R v xHz z K
Trong :
vz : H s k n nh hng ca vn tc vng, vi 1,94 / 1vv m s z .
Rz : H s xt n nhm b mt, vi 2,5 1,25 0,95a RR m z .
xHK :H s xt n nh hng ca kch thc bnh rng, vi 700 1a xHd mm K [ ] 527,3 1 0,95 1 500,94H MPa
Ta thy [ ]H H .
Vy iu kin bn tip xc c m bo.
6) Kim nghim rng v bn un:
Theo cng thc 6.65 ta c:
11
1
2. . . . .0,85. . .
F FF
tm m
T K Y Y Yb m d
Trong : FK : H s ti trng khi tnh ton v un, c tnh theo cng thc 6.71 . .F F F FvK K K K
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Vi FK l h s xt n tp chung ti trng khng u trn chiu rng vnh rng, theo
bng 6.21 ta c 1, 24FK , FK l h s xt n tp trung ti trng khng u gia cc rng 1FK , FvK l h s xt n nh hng ca ti trng ng, xc nh theo cng thc:
1
1
. .1 2
F mFV
F F
v b dKT K K
Vi : 10.( 1). . mF F
d uv g vu
theo bng 6.15 v 6.16 ta c: 0,016F ; 0 47g
51,12 (4 1)0,016 47 1,94 124F
v 12 35 51,121 1, 242 39253,79 1 1,15FV
K
Vy 1,24 1,24 1=1,54FK 1 1 0,6
1,71Y
0
1 1140
nY
11
1
24 24,74os( ) os(14,04)vn
zzc c
22
2
96 395,71os( ) os(75,96)vn
zzc c
1 0,39 x ; 2 0,39x Tra bng 6.18 ta c: 1 3,48FY ; 2 3,63FY
Vy 12 39253, 79 1,54 0, 6 1 3, 48 77,93
0,85 35 2,13 51,12FMPa
22 1
1
3,6377,93 80,983, 48
FF F
F
Y MPaY
Ta thy :
22
11
FF
FF
Vy iu kin bn un ca cp bnh rng cn c m bo.
7) Kim nghim rng v bn qu ti.
Theo cng thc 6.48 ta c: ax ax
[ ]Hm H qt H mK
vi: 480,77 H MPa ; 1,4qtK
max max480,77 1,4 526,66 [ ] 1260 H HMPa s MPa
Theo cng thc 6.49 ta c: ax ax[ ]Fm F qt F mK
max1 1 1 max77,93 1,4 109,102 [ ]F F qt FK MPa
max 2 2 2 max80,98 1, 4 113,37 [ ]F F qt FK MPa
Vy bn qu ti ca rng c tha mn.
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Trng HBK TPHCM N CHI TIT MY - 2011
SVTH: Trn ng Khu GVHD: PGS.TS Nguyn Hu Lc 15
8) CC THNG S V KCH THC CA B TRUYN BNH RNG CN: Chiu di cn ngoi 123,69eR mm
Modul vng ngoi 2,5tem mm Chiu rng vnh rng 35wb mm T s truyn
1 4u
Cp chnh xc 8 Gc nghing ca rng 00b
S rng ca cc bnh rng 1 224 ; 96z z
H s dch chnh chiu cao rng 1 20,39 ; 0,39x x
ng knh chia ngoi :
ed
1 1. 2,5 24 60e ted m z mm
2 2. 2,5 96 240 e ted m z mm Gc cn chia: 0 0
1 214,04 ; 75,96
Chiu cao rng ngoi : eh 2 2, 2 5,5e te te teh h m c m mm Chiu cao u rng ngoi : aeh
1 1( .cos ). (1 0,39 1) 2,5 3,475 ae te n teh h x b m mm 2 1 2. . 2 2,5 3,475 1,525 ae te te aeh h m h mm
Chiu cao chn rng ngoi : feh
1 1 5,5 3,475 2,025fe e aeh h h mm 2 2 5,5 1,525 3,975fe e aeh h h mm
ng knh nh rng ngoi :
aed 1 1 1 1 2. .cos 66,74ae e aed d h mm 2 2 2 2 2. .cos 240,74 ae e aed d h mm
3.2 Tnh Ton B Truyn Cp Chm: Cc thng s ban u
Cng sut u vo: 1 2,86P kW Moment xon: = 150692,41 S vng quay: = 181.25 / T s truyn: u = 3 Thi gian phc v: 7 nm Quay mt chiu, lm vic hai ca ( 1 nm lm vic 280 ngy, mt ca 8 gi) Ch ti: = , = 0.83
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Trng HBK TPHCM N CHI TIT MY - 2011
SVTH: Trn ng Khu GVHD: PGS.TS Nguyn Hu Lc 16
= 12 , = 60
1) Chn vt liu: Ta chn vt liu cho cp bnh tr rng nghing nh sau:
+ Bnh nh : Thp 45 ti ci thin t rn b mt HB = 270, c
1b=850(MPa);
1ch=580(MPa)
+ Bnh ln : Thp 45 ti ci thin t rn b mt HB =255, c
2b=750(MPa);
2450ch (MPa)
2) Xc nh ng sut cho php : Tnh s b ng sut un v ng sut tip xc cho php theo cc cng thc 6.1a v 6.1b ta c:
0lim.F Hl
HH
ks
;
0lim . .F Fc Fl
FF
k ks
Trong : limoF ,
0limH : ln lt l ng sut un v ng sut tip xc cho php ng vi s chu
k c s, tr s ca chng c tra bng 6.2: lim 1,8oF HB v 0 lim 2 70H HB
Fs , Hs : ln lt l h s an ton khi tnh v un v tip xc tra bng 6.2:1, 75Fs v 1,1Hs
Khi :
0 lim1 2 260 70 590F MPa 0 lim 2 1,8 260 468F MPa 0 lim 2 2 250 70 570H MPa
2Flin = 1,8.250 = 450(MPa) 0
lim1 1,8 250 450 MPaH
FcK : H s xt n nh hng t ti ,ly 1FcK (ti trong t mt pha)
HLK , FLK : H s tui th, c xch nh theo cng thc 6.3 v 6.4
HHOm
HLHE
NKN
; F FOmFLFE
NKN
y:
Hm , Fm : Bc ca ng cong mi khi th v tip xc v un vi HB 350 ly:6; 6H Fm m
FON , HON : S chu k thay i ng sut c s khi th v un v tip xc
FON = 4.106 vi tt c cc loi thp
2,430HO HBN H
7
7
10.97,1
10.05,2
2
1
HO
HO
N
N
HEN , FEN : s chu k thay i ng sut tng ng
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Trng HBK TPHCM N CHI TIT MY - 2011
SVTH: Trn ng Khu GVHD: PGS.TS Nguyn Hu Lc 17
V b truyn lm vic ch ti trng thay i nhiu bc nn theo cc cng thc 6.7 v
6.8 ta c:
260 . .
Hm
iHE i i
TN c n tT
; 60 . .Fm
iFE i i
TN c n tT
vi: c l s ln n khp trong mt vng quay ca bnh rng, c = 1, in , it : S vng quay v thi
gian lm vic ch i.
Ta c:
3 3 81 1
1 5N 60 1 181,25 31360 (1 0,83 ) 2,19.10 N6 6HE HO
2
1HlK
3 3 72 2
1 5N 60 1 60,42 31360 (1 0,83 ) 7,3.10 N6 6HE HO
1
1HlK
6 6 81 1
1 5N 60 1 181, 25 31360 (1 0,83 ) 1,5.10 N6 6FE FO
2
1FlK
6 6 72 2
1 5N 60 1 60, 42 31360 (1 0,83 ) 5.10 N6 6FE FO
1
1FlK
Nh vy: 1
590 1 536,361,1H
(MPA); 1
570 1 518,181,1H
(MPA)
Vi bnh tr rng nghing theo cng thc 6.12 ta c:
1 2
1 536,36 518,18 527,272 2H H H
(MPa) 21, 25H H
1486 1 1 277,7
1,75F
(MPa);
2
450 1 257,141,75F
(MPa)
ng sut qu ti cho php ,theo cc cng thc 6.10 v 6.11 ta c
Hmax = 2,8.ch 2 = 2,8.450 = 1260(MPa)
F1max = 0,8. ch 2 = 0,8.580 = 464(MPa)
F2max = 0,8.ch 2 = 0,8.450 = 360(MPa)
3) Xch nh cc thng s c bn ca b truyn : Xc nh s b khong cch trc theo cng thc 6.15a
2
32 22
. .( 1)
. .H
w aH ba
T ka k u
u
Trong :
+ ak : H s ph thuc vo vt liu ca cp bnh rng v loi rng.Theo bng 6.5 ta c 1/3 43 ak MPA
+ 2T : Mmen xon trn trc hai ca hp gim tc, = 150692,41 + H ng sut tip xc cho php ,
1/3527, 27 MPaH + 0,3ba tra theo bng 6.6
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Trng HBK TPHCM N CHI TIT MY - 2011
SVTH: Trn ng Khu GVHD: PGS.TS Nguyn Hu Lc 18
+ Hk H s k n s phn b ti trng khng iu trn chiu rng vnh rng khi ti v tip xc.
Theo bng 6.7 vi bd 0,64 , ta c 1,03Hk (s 5)
Suy ra: 3w 21, 0343 (3 1) 164, 7
51506
27, 27 3 0,392, 41a
(mm) ly w 165a mm
Ta c: w 2 0,3 165 49,5ba wb a mm v w1 w2 5 55b b mm
4) Xch nh cc thng s n khp Theo cng thc 6.17 ta c:
(0,01 0,02) (0,01 0,02) 165 1,65 3,3 wm a mm
Theo bng 6.8 chn mdul php 2,5m mm
Chn s b 010 , do 0cos( ) cos(10 ) 0,9848 , theo cng thc 6.19 ta xc nh
c s rng bnh nh: 1 wos( ) 0, 98482 2 165 32,5
( 1) 2,5 (3 1)cz a
m u
ly 1 32z
rng.
S rng bnh ln c xch nh theo cng thc 6.20: 2 2 1z u z 3 32 96 ly
2 96z rng >
Do t s truyn thc l 221
z 96 u 3z 32
1 2
w
32 96os( ) 2,5 0,972 2 165z zc m
a
0 14,14 14 8 28
Theo cng thc 6.18 ta tnh li khong cnh trc:
1 2w
32 962,5 1652 os( ) 2 0,97
z za mc
(mm)
Ta s dng rng khng dch chnh x1 = x2 = 0
Gc n khp
0tw
tanarctan 20,57 20 34'3''
ost c
5) Kim nghim rng v bn tip xc: Theo cng thc 6.33 ,ng sut tip xc trn b mt lm vic ca rng l
12
w w1
2. . ( 1). .. .
HH M H
T K uz z zb u d
Trong :
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Trng HBK TPHCM N CHI TIT MY - 2011
SVTH: Trn ng Khu GVHD: PGS.TS Nguyn Hu Lc 19
+ mz : h s k n c tnh vt liu ca bnh rng, theo bng 6.5 ta c 274mz (MPA)1/3
+ Hz : H s k n hnh dng b mt tip xc, theo cng thc 6.34 ta c 2.cos
sin(2. )b
Htw
z
y: b :Gc nghing ca rng trn hnh tr c s
Theo cng thc 6.35 ta c:
0 0cos cos 20,57 14,14 0, 236b ttg tg tg 013,27b
Do ta theo cng thc trn ta c 2.cos(13,27) 1,72sin(2.20,57)H
z
+ z: H s k n s trng khp ca rng . Xc nh theo cng thc 6.36c:
Ta c wsin sin 14,14
. 0,3 165 1,54 1. 2,5
bm
Do ta c 1 1 0, 771,694
z
Trong 1 2
1 11,88 3, 2 os( ) 1, 694cz z
ng knh vng ln bnh nh: w
w11652 2 82,5
1 3 1ad
u
(mm)
+ HK : H s ti trng khi tnh v tip xc ,tnh theo cng thc 6.39 . .H H H HVK K K K
Vi + HK :H s k n s phn b khng u ti trng trn chiu rng vnh rng, tra bng
6.7 ta c 1,03HK + HK : H s k n s phn b ti trng khng u gia cc i rng ng thi n khp
,tr s ca kH c tra theo bng 6.14 ta c 1,03HK + HVK : H s k n nh hng ca ti trng ng trong vng n khp, theo cng thc 6.41 ta c:
1
1
. .1 2
H w wHV
H H
v b dKT K K
Trong : 10
.( 1). . wH Hd uv g v
u
+ H : H s k n nh hng ca sai s n khp theo bng 6.15 ta c 0,002H + 0g : H s k n nh hng ca sai lch bc rng,ly 0 47g theo bng 6.16
+ v : Vn tc vng 1 1. . 3,14 82,5 181,25 0,7860000 60000
wd nv (m/s). Theo bng 6.13 ta chn
cp chnh xc cho b truyn l 9.
H82,5 4v 0,002 47 0,78 0,67
3
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Trng HBK TPHCM N CHI TIT MY - 2011
SVTH: Trn ng Khu GVHD: PGS.TS Nguyn Hu Lc 20
Vy ta c: 0,67 49,5 82,51 1,0092 150692, 41 1,03 1,03HV
K
1,03 1,03 1,009 1,07HK
Thay s vo cng thc trn ta c :
2
2 150692,41 1,07 (3 1)247 1,72 0,77 409,9549,5 3 82,5H
(MPa)
Xc nh chnh xc ng sut tip xc cho php:
vi 5 / 1vv m s z
2,5 1 ,25 ( ) 0,95a RR m z
700 1a XHd mm K
Theo 6.1 v 6.1a ta c:
[ ] [ ] 527,27 1 1 1 0,95 500,1H H sb v a XHz z K MPa
Ta thy 409,95 [ ] 500,1H H vy iu kin bn tip xc c m bo. n
gin trong qu trnh tnh ton ta ly w 50b (mm).
6) Kim nghim rng v bn un
Theo cng thc 6.43 ta c:
1 11
1
2 F FF
w w
T K Y Y Yb d m
Trong :
+ 1T :mmen xon trn bnh ch ng, N.mm + m : modul php + wb : chiu rng vnh rng w 50b (mm) + 1wd :ng knh vng ln ca bnh ch ng, mm
+ 1 1 0,591,694
Y
h s k n s trng khp ca rng (vi 1,694 )
+ 01Y
140
:h s k n nghing ca rng 01 14,14Y =0,899
140
+ YFi : H s dng rng ca bnh 1 v 2
vi
1v1 3 3
2v2 3 3
z 32z 35,06 cos 0,97
z 96z 105,19
cos 0,97
Vy theo bng 6.18 vi h s dch chnh 1 2x x 0 Ta c F1 F2Y 3,75 ; Y 3,60
+ KF: H s ti trng khi tnh v un . .F F F FVK K K K
y:
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Trng HBK TPHCM N CHI TIT MY - 2011
SVTH: Trn ng Khu GVHD: PGS.TS Nguyn Hu Lc 21
+ FK : H s k n s phn b ti trng khng u trn chiu rng vnh rng khi tnh v un ,theo bng 6.7 ta c 1,09FK
+ FK : H s k n s phn b ti trng khng u gia cc rng khi tnh v un ,theo bng 6.14 ta c 1,12FK
+ FVK : H s k n nh hng ca ti trng ng 1
1
. .1 2
F mFV
F F
v b dKT K K
vi 0. . . wF Fav g vu
Tra bng 6.15 v 6.16 ta c: + F 0,006 + 0 47g
1650,006 47 0, 78 1, 613F
v
Vy ta c: 1, 61 50 82,51 1, 02
2 150692, 41 1, 09 1,12FvK
1,02 1,09 1,12 1,245FK Ta c
+ 12 150692,41 1,245 0,59 0,899 3,75 72,37
50 82,5 2,5F
(MPa)
+ 22 11
3,672,37 69,483,75
FF F
F
YY
(MPa)
Ta thy
22
11
FF
FF
Vy iu kin bn un c m bo
7) Kim nghim rng v bn qu ti
Theo cng thc 6.48 ta c: Hmax H H max [ ]qtk
vi: 409,95 H MPa ; max 1, 4qtTkT
Suy ra: max max409,95. 1,4 485 [ ] 1260H HMPA MPa
max max. [ ]F F qt Fk
Suy ra: Fmax1 = F1.kqt = 72,371,4 = 101,32(MPA) < F1max
max1 1 1 max. 72,37 1, 4 101,32 [ ]F F qt Fk MPA
Fmax2 F2 qt F2 max.k 69,48 1, 4 97, 27 MPA [ ] Vy bn qu ti ca rng c tha mn.
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Trng HBK TPHCM N CHI TIT MY - 2011
SVTH: Trn ng Khu GVHD: PGS.TS Nguyn Hu Lc 22
8) Cc thng s v kch thc ca b truyn bnh tr rng nghing Khong cch trc 165wa (mm)
Mul php 2,5m (mm)
Chiu rng vnh rng 1
2
5550
w
w
bb
(mm)
T s truyn 3u
gc nghing ca rng 0 14 8 28
S rng ca bnh rng 1 2z 32 ; z 96
H s dch chnh 1 2 0x x (mm)
Cp chnh xc 9
ng knh vng chia :d
11
22
. 2,5 32 82, 47 cos 0,97
. 2,5 96 247,42cos 0,97
m zd mm
m zd mm
ng knh nh rng :da
1 1
2 2
2 82, 47 2 2,5 87, 47
2 247, 42 2 2,5 252, 42a
a
d d m mm
d d m mm
ng knh y rng :df
1 1
2 2
2,5 82, 47 2,5 2,5 76, 22
2,5 247,42 2,5 2,5 241,17 f
f
d d m mm
d d m mm
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Trng HBK TPHCM N CHI TIT MY - 2011
SVTH: Trn ng Khu GVHD: PGS.TS Nguyn Hu Lc 23
Phn bn:
KIM TRA BI TRN NGM DU
iu kin bi trn ngm du trong hp gim tc cn tr :
- Bnh rng cn cn c ngm ht chiu rng bnh rng ln h trong du.
- Bnh rng tr rng nghing cn ngm ht chiu cao rng rh v ti thiu l 10mm.
- Mc cao nht ca du khng vt qu 13
R mi bnh rng.
- Khong cch gia mc du cao nht v thp nht: ax min 10...15mh h mm .
1 - Xt bnh rng cn b dn:
Chn chiu cao bnh rng cn b dn cn phi ngm trong du l 12,5 mm.
Nh vy, chiu cao ti a m bnh rng cn cn phi ngm trong du l 27,5 mm.
Nh vy min 92,87H (mm )
2 - Xt bnh rng tr b dn:
Ta thy min2 292,87 126,21 84,143 3banhrangtru
H R
Do b truyn tha mn iu kin bi trn:
- min 92,87H mm
- ax 77,87mH mm
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Trng HBK TPHCM N CHI TIT MY - 2011
SVTH: Trn ng Khu GVHD: PGS.TS Nguyn Hu Lc 24
Phn nm:
THIT K TRC
4.1- Thit k trc 1:
Cc thng s ban u
Moment xon: = 39253,79 S vng quay: = 725 /
Thit K
Bc 1. Chn vt liu
Chn vt liu ch to l thp C45 thng ha. Cc thng s:
Gii hn bn: b = 600 MPa Gii hn chy: ch =340 MPa ng sut xon cho php: [ ] = 15 30
Bc 2. Chn s b ng knh
ng knh s b c tnh theo cng thc: 13 0.2 [ ]
Td
.Chn 1[ ] 15 MPa
1 331
1
39253, 79 23, 56 0, 2 0, 2 1 5
Td mm
Ta chn ng knh trc theo dy tiu chun: = 24
Bc 3. Chiu rng ln
T ng knh cc trc ta tra chiu rng ln i vi tng trc theo bng 10.2 sch Tnh ton Thit k h dn ng Trnh Cht-L Vn Uyn trang 189. Trc 1: = 17 .
Bc 4. Tnh ton phc tho cc kch thc di trc
Ta c: = 35 b rng rng bnh rng cn.
Di y l hnh v phc tho cc kch thc ca trc 1. T hnh v ny ta c cc kch thc ca trc 1 nh sau:
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Trng HBK TPHCM N CHI TIT MY - 2011
SVTH: Trn ng Khu GVHD: PGS.TS Nguyn Hu Lc 25
11 12,5 3 2,5 17 42,5 l d mm . Chn 11 42 l mm 13 11 1 1 2 13 13 1 0.5 0.5 cosl l b k k lm b
0 42 0,5 17 10 10 35 0.5 35 cos 14, 04
88,5 mm
Chn 13 90 l mm . y:
= 8 15: khong cch gia cc chi tit quay. Chn = 10. = 5 15 : khong cch t mt mt ti thnh trong ca hp. Chn = 10. 13 35lm mm : chiu di mayo bnh rng dn.
12 1 1, 2 1,5 1,5 24 36 lm d mm 12 12 3 1 0.5 0.5 0, 5 36 15 17 0,5 17 58,5nl lm k h b mm
Chn 12 60 l mm . Trong :
= 15 khong cch t mt mt chi tit quay n np = 17 chiu cao np v u bulng.
Bc 5. Tnh ton lc tc dng ln cc trc
Cc lc tc dng ln bnh rng cn dn l:
111
2 2 39253,7951,1
1532
6 tm
TF Nd
1 1 1 1 536 20 cos 14, 04 542,36 r tF F tg cos tg N 1 1 1 1 536 20 sin 14,04 135,63 a tF F tg sin tg N Lc tc dng ln bnh ai l:
101352 sin( ) 2.154,78.2.sin( ) 572
2 2
o
rF F z N
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Trng HBK TPHCM N CHI TIT MY - 2011
SVTH: Trn ng Khu GVHD: PGS.TS Nguyn Hu Lc 26
11 151,12. 135,63 3466, 7
2 2m
adM F Nmm
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Trng HBK TPHCM N CHI TIT MY - 2011
SVTH: Trn ng Khu GVHD: PGS.TS Nguyn Hu Lc 27
Mt phng Oyz:
1 1 1
1 1 1
1
1
2108.48 .90 .150 82333, 3
2556, 83448, 83
B C t r
B C r
B
C
Y Y F FY Y M F
Y NY N
Mt phng Oxz:
1 1 1
1 1
1
1
572.48 .90 0
1162619,84
B C r
B C
B
C
X X FX X
X NX N
Bc 6. Xc nh ng knh trc
Moment un tng ti cc tit din i:
- 2 212 3466,7 3466,70 A rx ryM M M Nmm
- 2 2 21277194,86 26033,28 81466,42rx ryBM M M Nmm
- 2 212 34320 0 34320C rx ryM M M Nmm
- 2 21 0rx ryDM M M
Moment tng ng ti cc tit din i:
- 12 2 2 2
11 0, 75. 3466,7 0, 75 39253, 79 34171, 08 tdA A AM M T Nmm
- 12 2 2 2
1 1 81466, 420, 75. 0, 75 39253,79 88274,7 tdB B BM M T Nmm
- 2 2 21 12
1 0, 75. 34320 0, 75 39253,79 48306,39 tdC C CM M T Nmm
- 1 12 2 2 2
1 0, 75. 0 0, 75 39253, 79 33994,78t DdD DM M T Nmm Tnh ng knh cc on trc:
- 1 31 334171,08 17,57
0,1 [ ] 0,1 63AtdAMd mm
- 1 31 388274, 7 24,1
0,1 [ ] 0,1 63BtdBMd mm
- 1 31 348306,39 19,72
0,1 [ ] 0,1 63tdC
CMd mm
- 1 31 333994,78 17,54
0,1 [ ] 0,1 63tdD
DMd mm
Chn ng knh cc on trc theo dy tiu chun: 1 18 Ad mm ; 1 25 Bd mm ;
1 25Cd mm ; 1 18 Dd mm ;
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Trng HBK TPHCM N CHI TIT MY - 2011
SVTH: Trn ng Khu GVHD: PGS.TS Nguyn Hu Lc 28
4.2 Thit k trc 2:
Cc thng s ban u
Moment xon: = 150692,41 S vng quay: = 181,25 /
Thit K
Bc 1. Chn vt liu
Chn vt liu ch to l thp C45 thng ha. Cc thng s:
Gii hn bn: b = 600 MPa Gii hn chy: ch =340 MPa ng sut xon cho php: [ ] = 15 30
Bc 2. Chn s b ng knh
ng knh s b c tnh theo cng thc: 13 0.2 [ ]
Td
.Chn 2[ ] 20 MPa
2
2 33
2
150692, 33,52 0.2 0, 2
4 20
1Td mm
Ta chn ng knh trc theo dy tiu chun: = 34
Bc 3. Chiu rng ln
T ng knh cc trc ta tra chiu rng ln i vi tng trc theo bng 10.2 sch Tnh ton Thit k h dn ng Trnh Cht-L Vn Uyn trang 189. Ta c: = 21
Bc 4. Tnh ton phc tho cc kch thc di trc
Ta c: = 35 b rng rng bnh rng cn.
Di y l hnh v phc tho cc kch thc ca trc 2. T hnh v ny ta c cc kch thc ca trc 2 nh sau:
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Trng HBK TPHCM N CHI TIT MY - 2011
SVTH: Trn ng Khu GVHD: PGS.TS Nguyn Hu Lc 29
22 22 22 10,5 0 51 21 10 55 6, 10ml b kl k .Chn 22 56 l mm
022 2223 13 2 1 56 0,5 51 35 os 75,96 10 95, 0,5 cos 7 5ml cl l b k Chn 23 95 l mm . y:
= 8 15: khong cch gia cc chi tit quay. Chn = 10. = 5 15 : khong cch t mt mt ti thnh trong ca hp. Chn = 10. 2 22 1,5 51lm d mm : chiu di mayo bnh rng tr dn.
23 1 1, 4 1, 4 34 47, 6 lm d mm : chiu di mayo bnh cn b dn.
1 221 22 23 2 2 51 47,3 6 3 10 2 10 21 169,6m ml l l k k b mm Chn 21 170 l mm .
Bc 5. Tnh ton lc tc dng ln cc trc:
Cc lc tc dng ln bnh rng cn b dn l:
2 1 1536 t tF F N
12 542,36 raF F N
12 135,63 arF F N
Lc tc dng ln bnh rng tr rng nghing dn l:
22w
313
22 2 150692, 41 0,97 3654, 29 os
2,5 32t n
TTF Nd
cm z
w3
3
3654, 29 20,57 1414, 22 cos 14,14
t tr
tgF tgF Ncos
3 3 3654, 2 19 920,64, 14a tF F tg tg N
33 382,4. 7920,6 37960,94
2 2m
adM F Nmm
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Trng HBK TPHCM N CHI TIT MY - 2011
SVTH: Trn ng Khu GVHD: PGS.TS Nguyn Hu Lc 30
22 251,12. 135,63 3466,7
2 2m
adM F Nmm
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Trng HBK TPHCM N CHI TIT MY - 2011
SVTH: Trn ng Khu GVHD: PGS.TS Nguyn Hu Lc 31
Mt phng Oyz:
2 2 3 2
2 2 3
2
2
2118, 29.56 .114 .39 142517,31
5821536
A D t t
A D t
A
D
Y Y F FY Y F
Y NY N
Mt phng Oxz:
2 2 3 2
2 2 2 3 3
2
2
1278,59.56 .114 .39 20660,34
736543
A D r r
A D r
A
D
X X F FX X M M F
X NX N
Bc 6. Xc nh ng knh trc
Moment un tng ti cc tit din i:
- 2 22 0rx ryAM M M Nmm
- 2 222 244683 32592 55307B rx ryM M M Nmm
- 2 2 22278686 1395115200 08rx ryCM M M Nmm
- 2 23 0rx ryDM M M
Moment tng ng ti cc tit din i:
- 2 22 2 2 2
2 0,75. 0,75 0 0 0d A At AM M T Nmm
- 2 2 22 22
2 0,75. 55307 0,75 150692, 41 141739tdB B BM M T Nmm
- 2 2 222
2 20,75. 0,75 150692, 41 191033 139508t C CdCM M T Nmm
- 2 22 2 2 2
2 0,75. 0 0,75 0 0D DtdDM M T Nmm Tnh ng knh cc on trc:
- 2 32 30 0
0,1 [ ] 0,1 63d
At AMd mm
- 2 32 3141739 28, 23
0,1 [ ] 0,1 63BtdBMd mm
- 2 32 3191033 31,18
0,1 [ ] 0,1 63CtdCMd mm
- 2 3320 0
0,1 [ ] 0,1 63DtdDMd mm
Chn ng knh cc on trc theo dy tiu chun: 2 25 Ad mm ; 2 30 Bd mm ; 2 32Cd mm; 2 25 Dd mm ;
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Trng HBK TPHCM N CHI TIT MY - 2011
SVTH: Trn ng Khu GVHD: PGS.TS Nguyn Hu Lc 32
4.3 Thit k trc 3:
Cc thng s ban u
Moment xon: = 429923,87 S vng quay: = 60,42 /
Thit K
Bc 1. Chn vt liu
Chn vt liu ch to l thp C45 thng ha. Cc thng s:
Gii hn bn: b = 600 MPa Gii hn chy: ch =340 MPa ng sut xon cho php: [ ] = 15 30
Bc 2. Chn s b ng knh
ng knh s b c tnh theo cng thc: 13 0.2 [ ]
Td
.Chn 3[ ] 25 MPa
3
33
33429923 44,14
0.2 0, 2 25,87Td mm
Ta chn ng knh trc theo dy tiu chun: = 45
Bc 3. Chiu rng ln
T ng knh cc trc ta tra chiu rng ln i vi tng trc theo bng 10.2 sch Tnh ton Thit k h dn ng-Trnh Cht-L Vn Uyn. Ta c: = 25 .
Bc 4. Tnh ton phc tho cc kch thc di trc
Di y l hnh v phc tho cc kch thc ca trc 3.
32 32 332 3 99 25 10, 75 5 15 90 4,mc nhl l l b k
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Trng HBK TPHCM N CHI TIT MY - 2011
SVTH: Trn ng Khu GVHD: PGS.TS Nguyn Hu Lc 33
Chn 32 94 l mm
33 1 33 3 2 0,5 67,5 25 10 10 66, 25 0,5 m kl l b k Chn 33 65 l mm . y: = 8 15: khong cch gia cc chi tit quay. Chn = 10. = 5 15 : khong cch t mt mt ti thnh trong ca hp. Chn = 10. 2 33 2, 2 99lm d mm : chiu di mayo na khp ni
3 33 1,5 67, 5lm d mm : chiu di mayo bnh rng tr b dn. = 15 khong cch t mt mt chi tit quay n np = 17 chiu cao np v u bulng.
Tuy nhin, 33 67 l mm do v tr ca hai bnh rng tr trong hp s (da vo kt cu
trc 2).
Khong cch gia hai ln 31 175l mm
Bc 5. Tnh ton lc tc dng ln cc trc
Cc lc tc dng ln bnh rng tr rng nghing b dn l: 4 3 3654,29 t tF F N
4 3 1414, 22 r rF F N 4 3 920, 6 a aF F N
Lc tc dng ln ni trc n hi l:
32 2 429923,870, 2 0,3 0, 2 0, 2 1322,84130nt k t
TF F ND
44 4247,42. 920, 6 113887, 43
2 2m
adM F Nmm
Mt phng Oyz: 3 3 4
3 4
3
3
2331, 45175 108 269 38819, 36
2110222
A C t nt
C t nt
A
C
Y Y F FY F F
Y NY N
Mt phng Oxz:
3 3 4
3 3 4
3
3
1414, 22108 67 113887, 43
1192222
A C r
A C
A
C
X X FX X M
X NX N
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Trng HBK TPHCM N CHI TIT MY - 2011
SVTH: Trn ng Khu GVHD: PGS.TS Nguyn Hu Lc 34
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Trng HBK TPHCM N CHI TIT MY - 2011
SVTH: Trn ng Khu GVHD: PGS.TS Nguyn Hu Lc 35
Bc 6. Xc nh ng knh trc Moment un tng ti cc tit din i:
- 2 23 0rx ryAM M M Nmm
- 2 232 2227880 128736 261729B rx ryM M M Nmm
- 2 232 2124347 124340 7rx ryCM M M Nmm
- 2 23 0rx ryDM M M
Moment tng ng ti cc tit din i:
- 3 32 2 2 2
3 0,75. 0,75 0 0 0d A At AM M T Nmm
- 2 2 23 32
3 0,75. 261729 0, 75 429923,87 455113tdB B BM M T Nmm
- 3 32 2 2 2
3 0,75. 0,75 429923,12 874347 392540,53 C CtdCM M T Nmm
- 3 32 2 2 2
3 0,75. 0 0, 75 429923,87 372325tdD D DM M T Nmm Tnh ng knh cc on trc:
- 3 33 30 0
0,1 [ ] 0,1 50d
At AMd mm
- 3 33 3455113 44,98
0,1 [ ] 0,1 50BtdBMd mm
- 3 33 3392540,53 42,8
0,1 [ ] 0,1 50tdC
CMd mm
- 3 33 3372325 40,07
0,1 [ ] 0,1 50DtdDMd mm
Chn ng knh cc on trc theo dy tiu chun: 3 45 Ad mm ; 3 48 Bd mm ; 3 45Cd mm ;
3 40Dd mm ;
Phn su:
KIM NGHIM THEN Bc 1. Kim nghim theo bn mi.
Ta kim nghim h s an ton :
s =s s
s + s [s]
Trong :
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Trng HBK TPHCM N CHI TIT MY - 2011
SVTH: Trn ng Khu GVHD: PGS.TS Nguyn Hu Lc 36
s =
K +
s =
K +
[s] l gi tr ca h s an ton cho php, ly gi tr l 3,nh vy khng cn kim nghim cng ca trc.
Mt khc, ta c :
Gii hn mi un ca thp Cacbon: = 0,436 = 0,436.600 = 261,6MPa
Gii hn mi xon: = 0,58 = 0,58.261,6 = 151,73MPa
V trc l trc quay nn ng sut un thay i theo chu k i xng nn: Gi tr trung bnh ca ng sut php ti tit din j l: = 0 Bin ng sut php ti tit din j:
= =MW
Trong : M = M + M
W : momen cn un, c tnh theo bng 10.6, trc c 2 rnh then.
W =d32
bt d td
Vi gi tr b, t c tra theo d trong bng 9.1
H dn ng xch ti thit k quay 1 chiu nn: Gi tr ng sut php ti tit din j:
= =
2 =T
2W
Trong :
T l momen xon ti tit din j
W : momen cn xon, c tnh theo bng 10.6, trc c 2 rnh then
W =d16
bt d t
d
Vi gi tr b, t c tra theo d trong bng 9.1
H s , : h s nh hng ca tr s trung bnh n bn mi, tra theo bng 10.7, ta c: = 0,05; = 0
H s K ; K c tnh theo cng thc 10.25; 10.26:
K =
K + K 1
K ; K =
K + K 1
K
Vi :
- H s tp trung ng sut do trng thi b mt K = 1,06 ,do trc c gia cng bng tin t nhm R = 2,5 0,63 ng vi gii hn bn = 600MPa.
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Trng HBK TPHCM N CHI TIT MY - 2011
SVTH: Trn ng Khu GVHD: PGS.TS Nguyn Hu Lc 37
-H s tng bn K = 2 ,b mt trc c thm Cacbon -Tr s ca h s K ; K tra theo bng 10.12, ng vi rnh then c ct bng dao phay ngn, ta c:
K = 1,76 ; K = 1,54 - , h s k n nh hng ca kch thc cc tit din trc ti bn mi bng 10.10.
Ta lp c bng kim nghim bn mi ca trc nh sau:
Trc V tr tit din Then
1b h t a= m
I
A1 (18) 6 6 3,5 327 899 0,93 0,9 10,6 21,8 25,3 7,9 7,5
B1,C1 (25) x 1533 3068 0,9 0,85 53 6,4 4,9 25 4,8
D1 (18) 6 6 3,5 327 899 0,93 0,9 0 21,8 x 7,8 x
II
A2,D2 (25) x 1533 3068 0,9 0,85 0 0 x x x
B2 (30) 10 8 5 1609 4260 0,88 0,81 34 17,7 7,4 8,7 5,64
C2 (32) 10 8 5 2078 5295 0,88 0,8 67 14,2 3,8 10,8 3,57
III
A3,C3 (45) x 8946 17892 0,83 0,77 14 12 17,2 12,3 10
B3 (48)
14 9 5,5
7960 18817 0,82 0,76 32,9 11,4 7,2 12,7 6,27
D3 (40)
14 9 5,5
4446 10729 0,85 0,78 0 17 x 8,8 x
Nh vy tt c cc h s an ton u ln hn 3. Trc tha iu kin bn mi
Bc 2. Kim tra trc v bn tnh
Cng thc kim nghim c tnh nh sau:
= + 3 [ ]
Vi:
= 0.1
= 0.2
[ ] = 0.8 = 0.8 340 = 272
Trc 1:
1 3
81466,42 52,140,1 25
; 1 339253,79 12,560,2 25
; 2 21 1 13 56,49 272td
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Trng HBK TPHCM N CHI TIT MY - 2011
SVTH: Trn ng Khu GVHD: PGS.TS Nguyn Hu Lc 38
Trc 2:
2 3 42,570,113950
28
3
; 2 3
150692,41 22,990,2 32
; 2 22 2 23 58,3 272td
Trc 3:
33261729 23,70,1 48
; 33429923,87 19, 440,2 48
2 23 33 3 41,2 272td Vy cc trc tha bn tnh.
Bc 3. Kim nghim then
Thng s ca then c tra theo bng 9.1a
iu kin bn dp v iu kin bn ct c dng
=2
. . ( ) [ ] = 150
=2. . [ ] = 60
Vi : T : moment xon trn trc ; d : ng knh trc ti tit din s dng then; = 0.8 : chiu di then; h : chiu cao then; t1 : chiu su rnh then;
Ta c bng kim nghim sau:
Trc ng knh d
1 18 6 6 3,5 28 62,3 25,96 18 6 6 3,5 29 60 25
2 30 10 8 5 44 76 23
32 10 8 5 40 78,4 23,54
3 48 14 9 5,5 50 102 26 42 14 9 5,5 80 77 20
Vy cc then u tha iu kin.
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Trng HBK TPHCM N CHI TIT MY - 2011
SVTH: Trn ng Khu GVHD: PGS.TS Nguyn Hu Lc 39
Phn by:
CHN LN V NI TRC I Trc u vo 1: Cc thng s ban u
ng knh vng trong d : 1 25 d mm S vng quay ca : 1 725 / n vng pht Quay mt chiu , lm vic 2 ca, ti va p nh.
Thit K
Bc 1. Chn loi ln Lc hng tm ti v tr cc a cn
2 2 21 1 1
22556,83 1162 2808,5 R B BBF X Y N 2 2 2
1 1 12619,8 448,83 765, 28 4C CRCF X Y N
Trc 1 l trc u vo, lm vic tc quay cao, li c bnh rng cn nn u tin dng a cn.
Bc 2. Chn kch thc ln Ta chn s b ln sau ( ph lc P.2.11)
S hiu d (mm) D (mm) B (mm) T (mm) r (mm) C (kN) (kN)
7205 25 52 15 16,25 1,5 13,5 23,9 17,9
Bc 3. Kim nghim kh nng ti ca
V tr t ln nh hnh v
Ta c : 1,5 1,5 13,5 0,36e tan tan
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Trng HBK TPHCM N CHI TIT MY - 2011
SVTH: Trn ng Khu GVHD: PGS.TS Nguyn Hu Lc 40
Lc dc trc ti B1:
1 1 1 1 10,83 0,83 0,36 765,28 135,63 93,04aB sC at rC atF F F e F F N
V : 1 10,83 0,83 0,36 2808,5 839,18sB rBF e F N
Do 1 1aB sBF F nn 1 1 839,18sB aBF F N
Lc dc trc ti C1:
1 1 1 839,18 135,63 974,81aC sB atF F F N
V: 1 228,67sCF N
Do 1 1aC sCF F nn 1 1 974,81aC sCF F N
Xt t s ( = 1 do vng trong quay):
1
1
839,18 0,3. 1 2808,5
aB
rB
F eV F
Tra bng 11.4 ta c : 1, 0X Y
1
1
974,81 1, 27. 1 765,28
aC
rC
F eV F
Tra bng 11.4 ta c: 0,4; 0,4 1,67X Y cotan
Ti trng quy c trn :
1 11 1 1 2808,5 0 1 1 2808,5 rB aB tB Q XVF YF K K N
1 11 0,4 1 765,28 1,67 974,81 1 1 1934RC aC C tQ XVF YF K K N
Vi :
= 1: vng trong quay = 1 : h s nh hng nhit = 1: p dng cho ch lm vic ti va p nh, qu ti ngn hn, tra bng 11.3
Nh vy 1 1 B CQ Q nn ta tnh ton theo thng s ti B1.
Chn thi gian lm vic ca a cn l:
15000 hL h
Thi gian lm vic tnh bng triu vng:
16 660 60 725 15000 652,5
10 10 hn LL tr
Kh nng ti ng: 103
1 2808,5 652,5 19626 19, 6 23, 9m
m BC Q L N kN C kN
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Trng HBK TPHCM N CHI TIT MY - 2011
SVTH: Trn ng Khu GVHD: PGS.TS Nguyn Hu Lc 41
Trong 103
m do s dng a.
Tui th tht s ca :
10323900 1258,19( )
2808,
5
mCL trQ
6
1
10 28924 6,460
hLL h nam
n
Nh vy a ny cn c thay sau 3 nm lm vic
Bc 4. Kim nghim kh nng ti tnh:
i vi a cn ta tra bng 11.6 ta c:
00 00,5; 0, 22 0, 22 13,5 0 , 92X Y cotan cotan
Theo cng thc 11.9
0 1 0 1 0 1 10,5 2808,5 0,92 93,04 1490B rB aB rBQ X F Y F N F
Nh vy 0 1 02808,5 17 900BQ N C N
Vy tha iu kin ti tnh.
II Trc trung gian 2: Cc thng s ban u
ng knh vng trong d : 2 25 d mm S vng quay ca : 2 181, 2 / 5 n vng pht Quay mt chiu , lm vic 2 ca, ti va p nh.
Thit K
Bc 1. Chn loi ln Lc hng tm ti v tr cc a cn
2 2 2 222 2 736 582 938A ArAF X Y N
22 2 2
2 22 5 1536 162943rD D DF X Y N
Trc 2 c bnh rng cn v bnh rng tr rng nghing nn u tin dng a .
Bc 2. Chn kch thc ln
Ta chn s b ln sau ( ph lc P.2.11)
S hiu d (mm) D (mm) B (mm) T (mm) r (mm) C (kN) (kN)
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Trng HBK TPHCM N CHI TIT MY - 2011
SVTH: Trn ng Khu GVHD: PGS.TS Nguyn Hu Lc 42
7205 25 52 15 16,25 1,5 13,5 23,9 17,9
Bc 3. Kim nghim kh nng ti ca
V tr t ln nh hnh v
Ta c : 1,5 1,5 13,5 0,36e tan tan
Lc dc trc ti A2:
32 2 920,6 542,36 378, 24at aaF F F N
2 2 2 2 20,83 0,83 0,36 1629 378, 24 108,5aA sD at rD atF F F e F F N
V : 2 20,83 0,83 0,36 938 280,3sA rAF e F N
Do 2 2aA sAF F nn 2 2 280,3sA aAF F N
Lc dc trc ti D2: 2 2 2 280,3 378, 24 658,5aD sA atF F F N
V: 2 486,7sDF N
Do 2 2aD sDF F nn 2 2 658,5aD sDF F N
Xt t s ( = 1 do vng trong quay):
2
2
280,3 0,3. 1 938
aA
rA
F eV F
Tra bng 11.4 ta c : 1; 0X Y
2
2
658,5 0, 4. 1 1629
aD
rD
F eV F
Tra bng 11.4 ta c: 0,4; 0,4 1,67X Y cotan
Ti trng quy c trn :
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Trng HBK TPHCM N CHI TIT MY - 2011
SVTH: Trn ng Khu GVHD: PGS.TS Nguyn Hu Lc 43
2 22 1 1 938 0 1 1 938 rA aA t AQ XVF YF K K N
2 22 0,4 1 1629 1,67 658,5 1 1 1751rD aD t DQ XVF YF K K N
Vi :
= 1: vng trong quay = 1 : h s nh hng nhit = 1: p dng cho ch lm vic ti va p nh, qu ti ngn hn, tra bng 11.3
Nh vy 2 2 A DQ Q nn ta tnh ton theo thng s ti D2.
Chn thi gian lm vic ca a cn l:
15000 hL h
Thi gian lm vic tnh bng triu vng:
26 6181, 260 60 15000 163,125
10 105 hn LL tr
Kh nng ti ng: 103
2 1751 163,125 8073 8,1 23, 9m
m DC Q L N kN C kN
Trong 103
m do s dng a.
Tui th tht s ca :
10323900 6077( )
175
1
mCL trQ
6 6
2
10 10 6077 55880460 60 181, 2
5h
LL hn
Bc 4. Kim nghim kh nng ti tnh:
i vi a cn ta tra bng 11.6 ta c:
00 00,5; 0,22 0,22 13,5 0 ,92X Y cotan cotan
Theo cng thc 11.9
0 2 0 2 0 2 20,5 1629 0,92 658,5 1420D rD aD rDQ X F Y F N F
Nh vy 0 2 016 29 20900DQ N C N
Vy tha iu kin ti tnh.
III Trc u ra 3: Cc thng s ban u
ng knh vng trong d : 3 45 d mm
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Trng HBK TPHCM N CHI TIT MY - 2011
SVTH: Trn ng Khu GVHD: PGS.TS Nguyn Hu Lc 44
S vng quay ca : 3 60, 42 / n vng pht Quay mt chiu , lm vic 2 ca, ti va p nh.
Thit K
Bc 1. Chn loi ln Lc hng tm ti v tr cc a cn:
2 2 23 3
23 2110 1192 2423rA A AF X Y N
2 2 23
23 3 2222 31422rC C CF X Y N
Ta chn dng a cn (do trc di)
Bc 2. Chn kch thc ln Ta chn s b ln sau ( ph lc P.2.11)
S hiu d (mm) D (mm) B (mm) T (mm) r (mm) C (kN) (kN)
2007109 45 75 19 20 1,5 11,33 40 34,8
Bc 3. Kim nghim kh nng ti ca
V tr t ln nh hnh v
Ta c : 1,5 1,5 11,33 0,3e tan tan .
Lc dc trc ti A3:
3 3 3 3 30,83 0,83 0,3 314 920,6 999aA sC at rC atF F F e F F N
V : 3 30,83 0,83 0,3 2423 603sA rAF e F N
Do 3 3aA sAF F nn 3 3 999sA aAF F N
Lc dc trc ti C3:
3 3 3 603 920,6 318aC sA atF F F N
V: 3 78sCF N
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Trng HBK TPHCM N CHI TIT MY - 2011
SVTH: Trn ng Khu GVHD: PGS.TS Nguyn Hu Lc 45
Do 3 3,aC sCF F cng chiu nn 3 3 318 78 396aC sCF F N
Xt t s ( = 1 do vng trong quay):
3
3
999 0, 41. 1 2423
aA
rA
F eV F
Tra bng 11.4 ta c : 0,4; 0,4 11,30,4 3 2X Y cotan cotan
3
3
396 1, 26. 1 314
aC
rC
F eV F
Tra bng 11.4 ta c: 0,4; 0,4 11,30,4 3 2X Y cotan cotan
Ti trng quy c trn :
3 33 0,4 1 2423 2 999 1 1 2967rA aA tA Q XVF YF K K N
3 33 0, 4 1 314 2 396 1 1 918rC aC C t Q XVF YF K K N
Vi :
= 1: vng trong quay = 1 : h s nh hng nhit = 1: p dng cho ch lm vic ti va p nh, qu ti ngn hn, tra bng 11.3
Nh vy 3 3 A CQ Q nn ta tnh ton theo thng s ti A3
Chn thi gian lm vic ca a cn l:
15000 hL h
Thi gian lm vic tnh bng triu vng:
6 6360 60 60, 42 15000 54,378
10 1
0hn LL tr
Kh nng ti ng: 103
3 2967 54,378 9839 9,8 40m
m AC Q L N kN C kN
Trong 103
m do s dng a.
Tui th tht s ca :
10340000 5832( )
296
7
mCL trQ
6 6
3
10 10 5832 1608739 60 60 6
0, 42h
LL hn
Bc 4. Kim nghim kh nng ti tnh:
i vi a bi chn ta tra bng 11.6 ta c:
00 00,5; 0, 22 0, 22 11,3 1 3 1,X Y cotan cotan
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Trng HBK TPHCM N CHI TIT MY - 2011
SVTH: Trn ng Khu GVHD: PGS.TS Nguyn Hu Lc 46
Theo cng thc 11.9
0 3 0 3 0 3 30,5 2423 1,1 999 2310A rA aA rAQ X F Y F N F
Nh vy 0 3 024 23 34800AQ N C N
Vy tha iu kin ti tnh.
IV Chn ni trc vng n hi: Moment xon ti trc 3 l: 3 429923,87 430T Nmm Nm
Tra bng 16.10a ta c cc thng s ni trc nh sau:
T Nm
d D L l Z B
500 40 170 80 175 110 71 130 8 3600 5 42 30 28 32
Bng 16.10b
l l
14 M10 20 62 34 15 28 1.5
Bc 5. Kim tra sc bn dp:
0 3
2 [ ]d dc
kTZD d l
Trong : [ ] = 3 ng sut dp cho php ca cao su. = 1,2 : h s ch lm vic
2 1,2 2,53 [ ]8 130 14 2
429923,878
d d
Vy ni trc tha sc bn dp.
Bc 6. Kim tra sc bn ca cht:
03
0
[ ]0.1
u uc
kTld ZD
Trong :
[ ] 80u MPa ng sut cho php ca cht.
20 1
153 4 41,52 2ll l
3
1,2 429923,87 41,5 75 [ ]0,1 14 8 130
u u
Vy cht tha iu kin bn.
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Trng HBK TPHCM N CHI TIT MY - 2011
SVTH: Trn ng Khu GVHD: PGS.TS Nguyn Hu Lc 47
Phn tm:
THIT K V HP v CC CHI TIT PH
I- Thit k v hp gim tc:
V hp gim tc c nhim v m bo v tr tng i gia cc chi tit v cc b phn ca my, tip nhn ti trng do cc chi tit lp trn v truyn n, ng du bi trn v bo v cc chi tit trnh bi.
Vt liu ch to v hp l gang xm, GX15-32
Chn b mt lp ghp gia np hp v thn hp i qua ng tm cc trc lp cc chi
tit thun tin v d dng hn. B mt ghp song song vi mt .
Mt y hp nghing mt gc t 10 v pha l tho du nhm thun tin hn trong vic tho du: du bi trn c thay th sch s, tng cht lng lm vic cho hp gim tc.
Hp gim tc c c cc thng s c bn sau:
Tn gi Thng s Chiu dy:
Thn hp Np hp 1
10mm 1 0,9 9mm
Gn tng cng Chiu dy e
8e mm
ng knh: Bulon nn 1d Bulon cnh 2d Bulon ghp np bch v thn 3d Vis ghp np 4d Vis ghp np ca thm 5d
1 14d mm
2 10,7 10d d mm
3 20,8 8d d mm
4 20,6 6d d mm
5 20,5 5d d mm Mt bch ghp np v thn: Chiu dy bch thn hp 3S Chiu dy bch np hp 4S B rng bch np v thn 3K
3 31,8 14,4S d mm
4 30,9 13S S mm
3 2 3 29K K mm
Mt hp: Chiu dy khng c phn li 1S B rng mt hp 1,K q
1 11,4 20S d mm
1 42 , 65K mm q mm Kch thc gi trc B rng mt ghp bolon cnh 2K
2 2 2 3 16 13 3 32K E R mm
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Trng HBK TPHCM N CHI TIT MY - 2011
SVTH: Trn ng Khu GVHD: PGS.TS Nguyn Hu Lc 48
Tm l bulon cnh 2E 2 22 2
1,6 1,6 10 16 ;1,3 1,3 10 13
E d mmR d mm
Khe h gia cc chi tit Gia bnh rng vi thnh hp Gia nh bnh rng ln vi y hp 1 Gia mt bn cc bnh rng vi nhau
10mm
1 3 30mm
10mm S lng bulon nn Z
200L BZ
Np :
Cc np vi thng s ca vis ghp, ng knh np : Trc 1
Trc 2 Trc 3
D 52 52 85
2D 80 65 100
3D 94,4 80 125
4D 42 42 75 h 8 8 10
4d M8 M8 M8 Z 4 4 6
II- Thit k cc chi tit ph: 1. Bulon vng:
Ren d 1d 2d 3d 4d 5d h 1h 2h Trng lng nng
c a
M10 45 25 10 25 15 22 8 6 200
2. Cht nh v: Chn cht nh v hnh cn.
3. Ca thm: (bng 18.5)
-
Trng HBK TPHCM N CHI TIT MY - 2011
SVTH: Trn ng Khu GVHD: PGS.TS Nguyn Hu Lc 49
A B A1 B1 C C1 K R Vis SL
100 75 150 100 125 - 87 12 M822 4
4. Nt thng hi: (bng 18.6)
Chn nt thng hi M272:
A B C D E G H I K L M272 15 30 15 45 35 32 6 4 10
M N O P Q R S 8 22 6 32 18 36 32
5. Nt tho du: (bng 18.7)
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Trng HBK TPHCM N CHI TIT MY - 2011
SVTH: Trn ng Khu GVHD: PGS.TS Nguyn Hu Lc 50
Chn nt tho du c kch thc:
d b m f L c q D S D0 M202 15 9 3 28 2,5 17,8 30 22 25,6
6. Mt ch du: (bng 18.9) Kch thc que thm du nh sau:
Kch thc mt knh (mm) D Dl l h 20 55 40 10 6
Phn chn:
CHN DU BI TRN v DUNG SAI LP GHP
I. Du bi trn hp gim tc:
Chn nht ph thuc vo vn tc vt liu ch to bnh rng, tra theo bng 18.11.
Vi vn tc vng trong khong 1 2,5 /m s , vt liu ch to bnh rng l thp C45 ti ci
thin ta tra c nht ca du 050 l 186 .
Tra bng 18-13 ta s dng loi du bi trn AK- 15.
II. Lp bnh rng ln trc v iu chnh s n khp: i vi bnh rng cn, vic iu chnh c tin hnh trn c hai bnh rng dn v b dn.
- Dch chuyn trc cng vi cc bnh rng c nh trn n nh b m iu chnh c chiu
dy khc nhau lp gia np v v hp. Vic iu chnh nh th ny kh thun tin.
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Trng HBK TPHCM N CHI TIT MY - 2011
SVTH: Trn ng Khu GVHD: PGS.TS Nguyn Hu Lc 51
- Dch chuyn cc bnh rng trn trc c nh, sau nh v ln lt tng bnh mt. Vic
iu chnh ny kh phc tp.
Lu : iu chnh phi t 70% trn b mt rng.
III. Dung sai v lp ghp: 1. Chn cp chnh xc:
- i vi bnh rng cp chnh xc c chn trong phn trc.
- i vi trc, then v cc rnh then chn cp chnh xc l 7.
- i vi cc l chn cp chnh xc l 6.
- i vi sai lch ca song song, thng gc, nghing, o mt u, o mt ton
phn l 6, thng, phng l 7, ng tm , i xng, giao trc, o hng tm
ton phn, tr, trn, v profin tit din dc l 5.
2. Chn kiu lp: - i vi then v bnh rng ta chn kiu lp H7/k6.
- i vi vng trong chn kiu lp k6.
- i vi vng ngoi chn kiu lp H7.
3. Bng dung sai lp ghp bnh rng:
Chi tit
Mi
lp
es
( m ) ei
( m ) ES
( m ) EI
( m ) di
ln nht (
m )
h
ln nht (
m )
Bnh cn
dn 76
Hk
+12 +1 +18 0 12 17
Bnh cn b
dn 76
Hk
+15 +2 +21 0 15 19
Bnh tr
dn 76
Hk
+18 +2 +25 0 18 23
Bnh tr b
dn 76
Hk
+18 +2 +25 0 18 23
4. Bng dung sai lp ghp ln:
Mi lp es
( m ) ei
( m ) ES
( m ) EI
( m ) di ln nht
( m ) h ln nht (
m )
25 6k +15 +2 0 -10 25 -
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Trng HBK TPHCM N CHI TIT MY - 2011
SVTH: Trn ng Khu GVHD: PGS.TS Nguyn Hu Lc 52
45 6k +18 +2 0 -12 30 -
52 7H 0 -15 +30 0 - 45
75 7H 0 -15 +30 0 - 45
5. Bng dung sai lp ghp then: ( bng 20.6)
Kch thc tit
din then b h
Sai lch gii hn chiu rng rnh
then
Chiu su rnh then
Trn trc Trn bc
Sai lch gii hn
trn trc 1t
Sai lch gii hn
trn bc 2t P9 D10
6 6 -0,042 +0,078 +0,030
0,1 0,1
10 8 -0,051 +0,098 +0,040
0,2 0,2
14 9 -0,061 +0,120 +0,050
0,2 0,2
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Trng HBK TPHCM N CHI TIT MY - 2011
SVTH: Trn ng Khu GVHD: PGS.TS Nguyn Hu Lc 53
TI LIU THAM KHO:
1. Trnh Cht - L Vn Uyn - Tnh ton thit k h dn ng c kh tp I v II- Nh
xut bn Gio Dc 2007.
2. Nguyn Hu Lc C s Chi Tit My NXB HQG TPHCM 2010.
3. Nguyn Trng Hip Chi Tit My Nh xut bn Gio Dc 2008.
4. Ninh c Tn Dung Sai v Lp Ghp Nh xut bn gio dc 2009.
5. P.OrLov - Fundamentals of Machine Design MIR Publishers. Moscow.
6. Jack M.Walker Manufacturing Engineering Marcel Dekker . NewYork