外文资料翻译-四轮驱动汽车黏性连接器

1、外 文 资 料 原 文 : 1 AB CT RACT 河南科技大学毕业设计(论文) T he v i sc o u s c o u p lin g is k n o w n ma in ly a s a d r i ve l in e co mp o n en t in f o u r w h e el d r iv e v eh ic les . D e v elo p m en t s in r ec en t y ear s , h o w ev e r , p o i n t to w ar d t h e p r o b a b il it y th at t h i s d e v

2、 i ce w i ll b ec o me a m ajo r p la y e r in ma i n st r ea m f r o n t - w h ee l d r iv e ap p lic at io n . P r o d u ct io n a p p l ica t io n i n Eu r o p e an an d J ap a n e s e f r o n t - w h e el d r iv e c ar s h a v e d e mo n s t r at e d t h at v is c o u s co u p li n g s p r o v i

3、d e s u b st a n ti al imp r o v e me n ts n o t o n ly i n tr act io n o n s li p p e r y s u r f a ce s b u t a ls o i n h an d in g an d s t ab i li t y e v e n u n d e r n o r ma l d r iv in g co n d it io n s . Th is p ap e r p r e se n t s a s e r io u s o f p r o v i n g g r o u n d t e st s

4、wh ic h in v es t ig a te th e e ff e ct s o f a v is c o u s co u p li n g i n a f r o n t- wh ee l d r iv e v e h ic le o n t r a ct io n an d h a n d in g . Tes t in g d e mo n s t r at es su b st a n t ia l tr act io n i mp r o v em en t s w h il e o n ly s l ig ht l y in f lu e n c in g st ee r

5、 i n g to r q u e . F ac to r s a f f ec t in g t h i s s t ee r i n g t o r q u e in f r o n t- w h ee l d r i v e v e h ic le s d u r in g st r a ig ht li n e d r i v in g ar e d es c r i b ed . K e y v e h ic le d e s ig n p a r a met er s ar e i d en t i f ie d w h i ch g r e at ly in f l u e n

6、ce t h e co mp at i b il it y o f li mit e d - s l ip d if f e r e n t ial s in f r o nt - w h e el d r iv e v e h ic le s . Co r n e r i n g te st s s h o w t h e in f l u e n ce o f t h e v is co u s co u p li n g o n th e s el f st e er in g b e h a v io r o f a f r o n t- w h e e l d r iv e v e

7、h ic le . F u r t h er t e st i ng d e mo n s t r at e s t h at a v eh ic le w it h a v is co u s l im it ed - s li p d if f e r e n t ia l ex h ib its an im p r o v ed st a b il it y u n d er a cc e ler at io n an d t h r o t t le- o f f ma n eu v er s d u r i n g c o r n e r i n g . 2 T H E VI S C

8、O US CO U P LI NG Th e v is co u s co u p li n g is a w e ll k n o wn c o m p o n e n t i n d r i v e tr ai n s. I n t h is p ap e r o n l y a s h o r t su mm ar y o f it s b a s ic f u n ct io n a n d p r in c ip le s h a ll b e g iv en . Th e v i sc o u s c o u p lin g o p e r at e s ac co r d in

9、g to t he p r in c ip le o f f lu id f r i ct io n , a n d is t h u s d ep e n d e n t o n s p e ed d if f er en c e. A s s h o w n in F i g u r e 1 t h e v is co u s c o u p l in g h a s s l ip co n tr o ll in g p r o p e r t ies in co n tr as t to to r q u e s en s i n g s y s t e ms. Th is mea n

10、s th a t t h e d r iv e t o r q u e w h i ch i s t r a n s mit t ed t o th e f r o n t 河南科技大学毕业设计(论文) w h ee ls i s a u to ma t ica ll y co n tr o ll ed in th e s en s e o f an o p t imi ze d to r q u e d is t r i b u t io n . I n a f r o n t - w h e el d r iv e v e h ic le t h e v i s co u s c o u

11、p lin g c an b e in s t a lle d i n s id e th e d i f f er e n t ia l o r ex t er n al ly o n an in t er med iat e sh af t . T he e x t er n a l so lu t io n is s ho w n i n F ig u r e 2 . Th is la y o u t h a s s o me s i g n i f ic an t a d v a n t ag e s o v er t h e in t e r n a l so lu t io n .

12、 F ir s t , t h e r e is u s u a ll y e n o u g h s p a ce av a il ab le i n t h e a r ea o f t h e in t er m ed i at e s h af t t o p r o v id e t h e r e q u ir ed v is c o u s c h ar a ct e r is t ic . T h is i s in co n t r a st t o t h e lim it ed s p a ce le f t in to d a y s f r o n t - a x l

13、e d i ff e r e n t ia ls . Fu r t he r , o n l y m in im al m o d i f ic at io n t o th e d if f e r e n t ial ca r r i er an d t r a n s mis s i o n c as e is r e q u i r e d . I n - h o u s e p r o d u ct io n o f d i ff e r e n t ia ls i s th u s o n l y s li g h t ly af f e ct ed . I n t r o d u

14、 ct io n as a n o p t io n ca n b e ma d e ea s i ly e s p ec ia l ly w h e n t h e sh af t a n d t h e v is co u s u n i t ar e s u p p l ie d as a c o mp le te u n it. F in a l ly, th e in t er m ed i at e s h af t mak e s it p o s s ib le to p r o v id e f o r s id e s h a f t s o f eq u al le n

15、g t h w it h t r a n s v er se l y in s t a lle d e n g in e s w h ic h ar e imp o r t an t t o r ed u ce t o r q u e s t ee r ( sh o w n la te r in s ec t io n 4 ) . Th is s p ec ia l d es i g n a ls o g iv e s a g o o d p o s s ib i lit y fo r s ig n i f ic an t w eig h t an d co st r e d u c t io

16、 n s o f t he v is co u s u n it . G KN Vis co d r i v e is d e ve lo p in g a lo w w e ig h t an d co st v is c o u s co u p li n g . By u s in g o n l y t wo st a n d a r d iz ed o u t er d ia met e r s , st a n d ar d iz ed p la t es , p l as t ic h u b s a nd ex t r u d ed mat e r ia l f o r t h

17、 e h o u s in g w h ic h c an ea s il y b e cu t t o d i f f er e n t le n g t h s , it i s p o s s ib l e t o u t i li ze a w id e r an g e o f v is c o u s c h ar ac te r is t ic s . A n e x am p le o f th is d e v e lo p me nt is s h o w n in F ig u r e 3 . 3 T RAC TI O N E FF E CT S As a to r q

18、u e ba l an c in g d ev ice , a n o p e n d i f f er e n t ia l p r o v id es eq u a l tr act at e e f f o r t t o b o t h d r iv i n g w h ee ls . I t a llo w s e ac h w h e e l t o r o t at e at d i ff e r e n t s p ee d s d u r i ng c o r n er in g w it h o u t t o r s io n w i n d - u p . T h es

19、 e ch a r a ct er is t ics , h o w ev er , c an b e d is a d v an t a g eo u s w h en ad h e s io n v ar ia tio n s b et w e en t h e lef t a n d r ig h t s id es o f t h e r o ad su r f ac e ( sp lit - ) li mit s t h e to r q u e tr an s m it te d fo r b o t h wh e e ls t o t h at w h i ch ca n b e

20、 s u p p o r t e d b y th e lo w - w h e e l. Wit h a v is co u s li mit ed - s li p d i f f er en t ia l, it is p o s s i b le to u t i li ze t h e 河南科技大学毕业设计(论文) h ig h er a d h es io n p o t en t ia l o f t h e w h ee l o n th e h ig h - s u r fa ce . Th is is s ch e ma t ica ll y s h o w n in F

21、ig u r e 4 . Wh e n f o r e x a mp l e, t h e max imu m t r an s mit t ab l e to r q u e f o r o n e w h ee l i s e x ce ed e d o n a s p li t- s u r fa c e o r d u r i n g co r n er in g w it h h ig h la te r a l a cc e ler at io n , a s p ee d d if f e r e n ce b e t we en th e t w o d r iv i n g

22、w h e e ls o c cu r s. T h e r e s u lt i ng s el f - lo ck in g to r q u e in t h e v i s co u s c o u p lin g r es i st s an y f u r t h e r in cr ea se in s p e ed d i f f er e n c e an d t r an s m its t h e a p p r o p r ia te to r q u e to t h e w h e el w it h t h e b et t er t r ac t io n po

23、 te n t ia l. I t ca n b e s e en in F ig u r e 4 t h at t h e d i f f er en c e in t h e t r a ct at e fo r c es r e su lt s i n a y aw i n g mo me nt w h ic h tr ie s t o t u r n t h e v e h ic le in to t h e lo w - s id e , To k ee p th e v eh ic le in a s t r a ig h t lin e t h e d r iv e r h as

24、 to co mp e n s at e t h i s w it h o p p o s it e s t eer in g in p u t. T h o u g h t h e f l u i d - f r ict io n p r i n c ip le o f th e v is co u s c o u p lin g a n d th e r es u lt in g so f t tr an s it io n f r o m o p e n t o lo c k i ng a ct io n , t h is is e as i l y p o s s i b le , t

25、 h e a p p r o p r iat e r e s u lt s o b t a in ed f r o m v e h ic le t es t s ar e s h o w n in F ig u r e 5 . Rep o r t ed a r e t h e a v er a g e st e er in g - w h e e l t o r q u e Ts an d t h e a v er a g e co r r ec t iv e o p p o s it e s t ee r i n g in p u t r e q u ir ed t o ma in t a

26、in a s t r a ig h t c o u r se d u r in g ac ce le r a ti o n o n a s p l it - t r ac k w it h an o p en a nd a v is c o u s d i ff e r e n t ia l. T h e d i ff e r e n ce s b e tw e en t h e v al u es w i th t h e o p e n d i ff e r e n t ia l a n d th o s e w it h t h e v i sc o u s c o u p lin g

27、ar e r el at iv e l y lar g e i n co mp a r is o n t o e ac h o t he r . H o w e v er , th e y ar e s m al l in a b so lu t e t er m s. S u b j ect iv e ly, t h e s t e er i n g in f lu e n c e i s n ea r ly u n n o t ic ea b le . T he t o r q u e st e er is a ls o in f lu e n ce d b y se v e r a l

28、k i n e mat ics p a r a me te r s w h ic h w i ll b e ex p la in e d in t h e n ex t s e ct io n o f t h is p ap er. 4 FA CTO R S AFF E CT IN G S TE E RI NG TO RQ U E As s h o w n in F ig u r e 6 t h e t r act at e f o r ce s le ad to a n in cr ea s e in t h e to e- i n r e sp o n s e p er wh e e l.

29、 Fo r d if f e r i n g t r a ct at e f o r ce s, Wh ic h ap p ea r w h en a cc e le r at in g o n s p l it - w it h li mit e d - s li p d i f f er en t ia ls , t h e to e- i n r e sp o n s e ch a n g e s p er w h ee l a r e a ls o d if f e r e nt . U n f o r t u n at e ly, t h is e f f ec t le ad s

30、t o an u n d e s ir a b le t u r n - i n r es p o n s e to t h e l o w - s i d e, i. e. Th e s a me y a w d ir ec t io n a s c au s e d b y th e d i ff e r e n ce i n t h e t r a ct at e f o r c es . F = F Wh e r e T = St ee r i n g To r q u e D i ff er e n ce 河南科技大学毕业设计(论文) Red u ce d t o e- in el

31、as t ic it y i s t hu s a n e ss e n t ia l r eq u ir e me n t f o r th e s u cc es s f u l fr o n t - ax le ap p l ica t io n o f a v is c o u s lim it ed - s li p d if f e r e nt ia l as w e ll as an y o th e r t y p e o f li mit e d - s l ip d if f e r e n t ial. G en er al l y t h e fo ll o w in

32、 g e q u at i o n s a p p l y t o t h e d r i v in g f o r ce s o n a w h ee l T VWit h FT = Tr a ct at e Fo r ce FV = Ver t ica l W h ee l Lo ad = Ut i liz e d A d h e s io n Co e f f i ci en t Th e s e d r iv i n g f o r ce s r e s u lt in s t ee r i n g to r q u e at ea ch w h e el v ia th e w h

33、ee l d i st u r b an c e le v e l a r m “e ” a n d a s t eer in g to r q u e d if f e r e n ce b et w ee n t h e w h ee ls g iv e n b y th e e q u a tio n : Te = e cos (FH hi FH lo ) ee = W he e l D i st u r ba n c e Le v el A r m = K in g P in A n g le h i= h i g h - s id e s u b s cr ip t lo = lo

34、w - s id e s u b s cr ip t I n t h e ca s e o f f r o n t- w h ee l d r iv e v eh i c le s w it h o p e n d if f e r e nt i al s, Ts i s a lmo s t u n n o t ic ea b l e, s in c e t h e to r q u e b ias ( FT hi / FH lo ) is n o mo r e t h a n 1 . 3 5 . Fo r ap p lic at i o n s w it h li mi te d - s l

35、 ip d if f e r en t ia ls , ho w ev e r, t h e in f lu e n c e is s ig n i f ic an t . Th u s t h e w h e el d is tu r b a n ce le v e r a r m e s h o u ld b e a s s m al l a s p o s s ib l e. D i ff e r i n g w h e el lo a d s al so lea d to a n i n cr e as e in Te s o th e d if f er en c e s h o u

36、 l d a ls o b e a s s mal l as p o s s ib le . Wh e n t o r q u e is tr an s m it te d b y an ar t i cu l a te d CV- J o in t , o n t h e d r iv e s id e ( s u b s c r ip t 1 ) an d th e d r iv e n s id e ( s u b s c r ip t 2 ) , d i f f er in g s e co nd ar y mo me n ts ar e p r o d u c ed t h at m

37、u s t h a v e a r e act io n in a v e r t ica l p l an e r e lat i v e t o t h e p lan e o f a r t icu la t io n . Th e ma g n it u d e a nd d ir ec t io n o f t h e s ec o n d a r y m o m en t s ( M ) a r e ca lc u la t ed as f o llo w s ( s ee F ig u r e 8 ) : D r iv e s id e M1 = T 2 tan( v / 2)

38、T / tan v河南科技大学毕业设计(论文) D r iv e n s id e M 2 = T 2 tan( Wit h T 2 = FT rdynv/ 2) + T/ tan vT=f (T 2, , Jo int system ) Wh e r ev= Ve r t ic al A r t ic u la t io n A n g l e r= Re s u lt in g A r t ic u la t io n A n g l e = D y n a mi c W h ee l Rad iu s dynT= Av er ag e To r q u e Lo s s Th e c o

39、 mp o n e n t M 2 co s act s a r o u n d t h e k in g - p in a x is ( s ee f i g u r e i. e . n eg a t iv e ) t h e s e co n d ar y mo m en t s co u n te r a ct t h e mo me n t s c au s e d 7 ) a s a st ee r i n g to r q u e p er w h e el a n d a s a st e er in g to r q u e d if f e r e n ce b et w

40、ee n t h e w h ee ls a s f o llo ws : T = co s (T2 tan / 2 + T / sin ) w hi (T2 tan / 2 T / tan ) wli Wh e r e T = S t eer in g To r q u e D if f er en c e W = W h ee l s id e s u b s cr ip t I t is th er e f o r e a p p a r en t t h at n o t o n ly d if f e r i ng d r iv i n g t o r q u e b u t a l

41、so d i ff e r i n g a r t icu lat io n s ca u s ed b y v ar io u s d r iv es h af t le n g t h s ar e a lso a fa ct o r . Re f er r in g to t h e mo me n t- p o ly g o n i n F ig u r e 7 , th e r o t at io n a l d ir e ct io n o f M 2 o r T r es p e ct iv e l y c h a n g e, d e p en d in g o n t h e

42、 p o s it io n o f t h e w h e el - ce n t er t o t h e g e ar b o x o u t p u t . Fo r t h e n o r ma l p o s it io n o f th e h a lf s h af t s h o w n in F i g u r e 7 ( w h e el- ce n t er b e lo w t h e g e ar b o x o u tp u t jo in t ) t h e s ec o n d a r y mo men t s wo r k in t h e s am e r

43、 o t at i o n a l d ir e ct i o n as th e d r iv in g f o r ce s . Fo r a mo d if i ed s u s p e n s io n la y o u t ( w h ee l- c e n te r a b o v e g e ar b o x o u tp u t jo in t , vb y th e d r i v in g f o r ce s . T h u s f o r g o o d co mp at i b il it y o f t h e f r o n t a x le w it h a l

44、 im it ed - s lip d if f e r e n t ia l, t h e d e s ig n r eq u ir e s : 1 ) v er t ic a l b e nd in g an g le s w h ic h ar e c en t e r ed ar o u n d v = 0 o r n eg at iv e ( v 0) w ith sa me v a lu e s o f v o n bo th lef t a n d r ig h t s id e s; an d 2 ) s id e s h af t s o f eq u a l le n g

45、t h . 河南科技大学毕业设计(论文) 附 : *D im ens i onal T ol era nc es a nd S u rfa ce R o ughn ess Bec au s e o f th e h i g h l y co mp et it i v e n a t u r e o f mo s t man u f ac t u r i n g b u s in es s es , th e q u es t io n o f f in d in g w ay s t o r ed u ce co st is e v er p r e se n t . A g o o d st

46、 a r t in g p o in t f o r co st r e d u ct i o n i s in th e d e s ig n o f t h e p r o d u ct . T he d e s ig n e n g i n ee r s h o u ld a lw a y s k ee p in min d th e p o s s ib le a lte r n a ti v es av a il ab l e to h im in ma k in g h i s d es i g n . I t is o ft e n im p o s s ib le to d e

47、t e r min e t h e b e st a lt er n at iv e s w it h o u t a ca r e f u l a n a ly s i s o f t h e p r o b a b le p r o d u ct i o n co st . De s ig n in g f o r f u n ct io n , in t er ch a n g e ab il it y , q u a lit y , a n d ec o n o my r eq u ir e s a ca r e fu l s tu d y o f to ler an c es , s

48、u r f ac e f in is h e s , p r o ce s s, ma te r ia l s, an d eq u ip me n t.T o a ss u r e s o u n d a n d ec o n o mi ca l d e s ig n fr o m a p r o d u c ib il it y st a n d p o in t , c ar ef u l co n s i d er at io n o f t h e f o llo w in g g e n er al d e s ig n r u l es b o th se p ar at e l

49、y a n d t o g et h e r i s o f p a r a mo u nt imp o r t an ce . Th e o r d er o f imp o r t an c e ma y v ar y ac co r d i n g to d e s ig n r eq u ir e me n ts , o r f ac to r s , b u t t h e o v er al l imp o r t an c e alw a y s r em ai n s th e s a me.( 1 ) S e ek s imp li ci t y. D e s ig n f

50、o r m ax i mu m s imp li cit y in f u n ct io n a l an d p h y s i ca l c h a r ac t er ist ic s . ( 2 ) D et e r mi n e th e b e st p r o d u ct i o n m et h o d . S ee k t h e h e lp o f a p r o d u ct io n en g in e er to d e s ig n f o r t h e mo s t eco n o m ic al p r o d u ct io n me th o d s

51、 . ( 3 ) A n a ly z e m at e r ia ls . S e le ct ma te r i als t h a t w i ll le n d t h em s el v es to lo w - co s t p r o d u ct io n as we ll a s t o d es ig n r eq u ir e me n ts . ( 4 ) E li mi n at e f ix t u r n i n g an d ha n d lin g p r o b le ms . D es i g n f o r e as e o f lo c at i n

52、g , s et t in g u p , an d h o ld in g p a r ts . ( 5 ) E mp lo y ma x imu m a cc ep ta b le to le r a n ce s an d f in is h e s. S p ec if y s u r f a ce r o u g h n e s s a n d ac cu r ac y n o gr eat e r t h a t w h ic h is co mme n s u r a te w it h t h e 无 效 o f p ar t o r me ch a n i s m b e i

53、n g d e s ig n ed . A n d t h e p r o d u ct io n me t ho d o r me th o d s co n te mp lat e d . To ler an c es o n f in i s h an d d ime n s io n s p la y an imp o r t an t p ar t i n t h e f in a l a ch i ev em en t o r 河南科技大学毕业设计(论文) a b s en c e o f p r a ct ic a l p r o d u c t io n d es i g n

54、. A co mp r e h e n s iv e s tu d y o f t h e p r in ci p le s o f in te r c h an g ea b il it y i s es s e n t ia l f o r a t h o r o u g h u n d e r s ta n d i n g a n d f u l l a p p r ec ia t io n o f lo w - co st p r o d u ct io n t e ch n iq u e s . I n t er ch a n g e ab i l it y is t he k e

55、y to su cc es s f u l p r o d u ct io n r eg a r d l es s o f q u a lit y . D et a il s o f al l p ar t s s h o u l d b e s u r v e y ed ca r e f u ll y t o a ss u r e n o t o n ly in ex p en s i v e p r o c es s i ng b u t a ls o r a p id , ea s y as s e mb l y an d ma in t e na n c e. I t mu st b

56、e r e me mb e r ed t h a t e ac h p r o d u ct io n me th o d h a s a we ll es t ab li s h ed le v e l o f p r ec i s io n w h ic h c a n b e ma in t a in e d i n c o n t in u o u s p r o d u ct io n w i th o u t ex c eed in g n o r ma l b a s ic co st . E co n o m ic m an u f ac tu r in g d o es n

57、o t “j u st h ap p en . ” I t st a r t s w it h d e s ig n an d co n s id e r s p r ac t ica l l im it s o f ma ch in e t o o ls , p r o ce ss e s , to ler an c es , an d f in is h e s. Ne it h er d i me n s io n a l t o ler a n c es n o r s u r f a ce r o u g h n es s s h o u ld b e s p ec if i ed

58、t o li mit s o f ac cu r ac y c lo s e r t h a n t h o se w h ic h t he ac t u al f u n ct io n o r d e s ig n n e ce s s it at e. T h i s is do n e t o as s u r e t h e a d v a n ta g es o f lo w es t p o s s ib le co st a n d f a st e st p o s s ib l e p r o d u c t io n . Wit h o u t n e ed in g

59、t o k n o w h o w to o p er a te a p ar t icu lar mac h in e to at ta i n t h e d e s ir ed d eg r ee o f s u r fa c e r o u g h n e s s, th e r e ar e c er t a in as p e ct s o f a ll t h e se me t h o d s w h ic h s h o u l d b e u n d er st o o d b y t h e d es i g n en g in e er . K n o w le d g

60、 e o f su ch f act s a s d e g r ee o f r o u g h n e ss o b ta in e d b y a n y o p e r at io n , a n d t h e ec o n o mic s o f at ta in in g a s mo o th e r s u r f ac e w it h ea c h o p e r at io n , w il l a id h i m in d e ci d i n g ju s t w h ic h s u r f ac e r o u g h n e ss to s p ec if