8/13/2019 Us 8556209

1/16

1 2 ) United S t a t e s PatentUS008556209B2

1 0 ) P a t e n t N 0 . : US , 5 5 6 , 2 0 9 B 2Luce ( 4 5 ) Date o f P a t e n t : O c t . 1 5 , 2013

( 5 4 ) ELECTRIC-POWERED TRANSFER ( 5 6 ) R e f e r e n c e s C i t e dCYLINDER FOR LANDING GEAR SYSTEM U . S . PATENT DOCUMENTS( 7 5 ) I n v e n t o r : W i l l i a m E . L u c e , C o l l e y v i l l e , TX ( U S ) 2,954,232 A * 9/1960 Auer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 473/155

- . - - 4,540,142 9/1985 Veaux t a 1 . . . . . . .. 244/102 R( 7 3 ) A S S 1 g I 1 e e ~ ( g l g d r l c h C O F P O I a t I O I I , C h a r l o tt e , NC 4 , 5 5 2 , 3 2 4 A 1 1 / 1 9 8 5 H r u s c h 2 4 4 / 1 0 4 PP( ) 4 , 6 3 0 , 7 8 8 A * 1 2 / 1 9 8 6 Veaux et a 1 . 244/104 FP

_ _ _ _ _ 4,907,760 3/1990 Sealey et a 1 . 244/100 R( * ) Not1ce: Subject t o any d 1 s c l a 1 m e r , the term ofth1s 5 , 9 0 8 , 1 7 4 A * 6 / 1 9 9 9 C h u r c h i l l e r a 1 , , , , , , 244/102 SSpatent i s extended or adjusted under 3 5 * dbU . S . C . 1 5 4 ( b ) by 6 7 8 d a y s . we Y exammer

( 2 1 ) A p p l . N 0 . : 1 2 / 7 7 8 , 8 5 2 Primary Examiner* i c h a r d P r i c e , J r .( 7 4 ) A t t o rn e y , A g e n t , or Firm * n e l l ilmer L . L . P .( 2 2 ) F i l e d : May 2 , 2 0 1 0

( 6 5 ) P r i o r P u b l i c a t i o n Data ( 5 7 ) ABSTRACTUs 2010/0219290 A1 Sep 2 2010 A shock s t r u t f o r an a i r c r a f t l a n d i n g g e a r h a v i n g a r e t r a c t

_ _ actuator t h a t i s movea ble i n length t o deploy o r r e t r a c t theRelated U - s - APPh c atmn Data l a n d i n g g e a r , t h a t i n c l u d e s a s h r i n k s t r u t and t r a n s f e r d e v i c e .( 6 3 ) C o n t i n u a t i o n - i n - p a r t o f a p p l i c a t i o n N o . 1 2 / 2 5 6 , 2 0 4 , T h e S h r i n k S t r u t may e C o m p r e s s e d i n l e j n g t h f o r s t o w a g e i n

? l e d o n Oct 2 2 2 0 0 8 , HOW pat NO_ 8,070,095 t h e f u s e l a g e . The r a n s f e r d e v 1 c e ma y be 1 n c l o s e d ?uld c o mm u n i c a t i o n W i t h t h e s t r u t s h r i n k f o r t r a n s f e r r i n g a n d r e c e i v i n g( 5 1 ) I n ; C ] _ h y d r a u l i c ? u i d t o a n d f r o m t h e s t r u t s h r i n k . Wh e n c t u a t e d by

B64C 5 / 1 0 (200601) a n a i r c r a f t h y d r a u l i c o r e l e c t r i c s y s t e m i n d e p e n d e n t o f a n y( 5 2 ) us L motion o f t h e r e t r a c t a c t u a t o r , t h e t r a n s f e r d e v i c e may d r i v e

USPC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 244/102 s s hydraulic ?uid t o t h e Sm S h n n k thereby Compressing or( 5 8 ) F i e l d o f C l a s s i ? c a t i o n S e a r c h s h r i n k i n g t he s h r i n k s t r u t t o a p a r t i a l l y c o m p r e s s e d l e n g t h .

USPC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 244/100 R, 102 R, 102 SSS e e a p p l i c a t i o n ? l e f o r c o m p l e t e s e a r c h h i s t o r y . 2 0 C l a i m s , 9 Drawing S h e e t s

8/13/2019 Us 8556209

2/16

8/13/2019 Us 8556209

3/16

US. P a tent 0a. 5 , 2 0 1 3 S h e e t 2 o f 9 US , 5 5 6 , 2 0 9 B2

8/13/2019 Us 8556209

4/16

US. P a tent 0a. 5 , 2 0 1 3 S h e e t 3 o f 9 US , 5 5 6 , 2 0 9 B2

F i g . 3 A

8/13/2019 Us 8556209

5/16

8/13/2019 Us 8556209

6/16

US. P a tent 0a. 5 , 2 0 1 3 S h e e t 5 o f 9 US , 5 5 6 , 2 0 9 B2

F i g5III IA

F i gA

8/13/2019 Us 8556209

7/16

US. P a tent 0a. 5 , 2 0 1 3 S h e e t 6 o f 9 US , 5 5 6 , 2 0 9 B2

3 6L

N

8/13/2019 Us 8556209

8/16

US. P a tent 0a. 5 , 2 0 1 3 S h e e t 7 o f 9 US , 5 5 6 , 2 0 9 B2

g 2 3

7 4 7 1 7 7 11 7 1 7 7 1

F l g . 7 5i g . 7 A

8/13/2019 Us 8556209

9/16

US. P a tent 0a. 5 , 2 0 1 3 S h e e t 8 o f 9 US , 5 5 6 , 2 0 9 B2

700

F I G . 8 BIGBA

8/13/2019 Us 8556209

10/16

US. P a tent 0a. 5 , 2 0 1 3 S h e e t 9 o f 9 US , 5 5 6 , 2 0 9 B2

720

702

706

708

7 7 0 /72728726

7 2

F I G . 9

8/13/2019 Us 8556209

11/16

8/13/2019 Us 8556209

12/16

US 8 , 5 5 6 , 2 0 9 B23

i n t o t h e s h r i n k s t r u t . The r a n s f e r p i s t o n may e s e a l e d a g a i n s tt h e i n n e r W a l l o f t h e t r a n s f e r c y l i n d e r to s e p a r a t e a n d i s o l a t et h e a i r c r a f t s h y d r a u l i c s u p p l y ? u i d f r o m t h e s h o c k s t r u t sv o l u m e o f t r a n s f e r ? u i d . A y d r a u l i c s u p p l y a n d v a l v i n gmechanism may e p r o v i d e d on h e a i r c r a f t f o r s u p p l y i n g andd i r e c t i n g h y d r a u l i c s u p p l y ? u i d t o o p e r a t e t h e t r a n s f e r c y l i nd e r .The f o r e g o i n g and o t h e r f e a t u r e s o f t h e i n v e n t i o n a r e h e r ei n a f t e r f u l l y d e s c r i b e d a n d p a r t i c u l a r l y p o i n t e d o u t i n t h ec l a i m s , the f o l l o W i n g d e s c r i p t i o n , a n d t h e a n n e x e d d r a W i n g ss e t t i n g f o r t h i n d e t a i l one o r more l l u s t r a t i v e embodiments oft h e i n v e n t i o n , s u c h b e i n g i n d i c a t i v e , h o W e v e r , o f b u t one o r af e W o f t h e v a r i o u s Ways i n Which t h e p r i n c i p l e s o f t h e i n v e nt i o n may b e e m p l o y e d .

BRIEF DESCRIPTION OF THE DRAWINGSP r e f e r r e d and a l t e r n a t i v e embodiments o f t h e p r e s e n t

i n v e n t i o n a r e d e s c r i b e d i n d e t a i l beloW With r e f e r e n c e to t h ef o l l o W i n g d r a W i n g s :FIGS. 1A nd 1 B a r e a p a i r o f l e v a t i o n vieWs of an exem

p l a r y a i r c r a f t l a n d i n g g e a r i n a c c o r d a n c e W i t h a n embodimento f t h e i n v e n t i o n , W h e r e i n F I G . 1 A s h o W s t h e l a n d i n g g e a rf u l l y e x t e n d e d and I G . 1 B shoWs t h e l a n d i n g g e a r i n a s h r u n ks t a t e ;FIG. 2 i s an i s o m e t r i c vieW of an exemplary s t r u t andt r a n s f e r c y l i n d e r i n a c c o r d a n c e W i t h an embodiment o f t h ei n v e n t i o n ;

FIGS. 3A and 3 B a r e a p a i r of e l e v a t i o n vieWs i n c r o s ss e c t i o n o f a n e x e m p l a r y t r a n s f e r c y l i n d e r i n a c c o r d a n c e W i t han embodiment of h e i n v e n t i o n , Wherein F I G . 3A hoWs t h et r a n s f e r c y l i n d e r When t h e l a n d i n g g e a r i s i n a n e x t e n d e d o runshrunk t a t e and I G . 3 B shoWs t h e t r a n s f e r c y l i n d e r W hent h e l a n d i n g g e a r i s i n a s h r u n k s t a t e ;

F I G . 4 i s an l e v a t i o n vieW n c r o s s - s e c t i o n o f an exemplarys t r u t i n accordance With an embodiment of t h e i n v e n t i o nshoWn When t h e l a n d i n g g e a r i s i n an e x t e n d e d o r unshrunks t a t e ;FIGS. 5A and 5B a r e a p a i r of e l e v a t i o n vieWs i n c r o s ss e c t i o n o f a s h r i n k chamber r e g i o n o f t h e s t r u t o f F I G . 4 ,Wherein FIG. 5A h o W s t h e s t r u t i n an extended o r unshrunks t a t e and FIG. 5 B s h oWs t h e s t r u t i n a shrunk t a t e ;

F I G . 6 i s a s c h e m a t i c h y d r a u l i c d i a g r a m o f a n e x e m p l a r yl a n d i n g g e a r shock s t r u t i n a c c o r d a n c e W i t h an embodimento f t h e i n v e n t i o n f o r s hr i n k i n g a s i n g l e l a n d i n g g e a r ;

FIGS. 7A and 7 B a r e a p a i r of e l e v a t i o n vieWs i n c r o s ss e c t i o n of an exemplary compensator i n a c c o r d a n c e W i t h anembodiment o f t h e i n v e n t i o n , W h e r e i n F I G . 7 A shoWs t h ecompensator When h e s h o c k s t r u t i s f u l l o f ? u i d and F I G . 7 BshoWs t h e compensator When t h e shock t r u t i s loW on ? u i d ;

FIGS. 8A and 8B a r e a p a i r of e l e v a t i o n vieWs i n c r o s ss e c t i o n of t r a n s f e r c y l i n d e r i n accordance With an embodiment o f t h e i n v e n t i o n , W h e r e i n F I G . 8 A shoWs t h e t r a n s f e rc y l i n d e r W hen t h e l a n d i n g g e a r i s i n a n unshrunk s t a t e andF I G . 8B s h o W s t h e t r a n s f e r c y l i n d e r When h e l a n d i n g g e a r i si n a shrunk t a t e ;

F I G . 9 i s an l e v a t i o n a l vieW i n c r o s s - s e c t i o n o f h e t r a n s f e rc y l i n d e r f r o m F I G . 8 B , W h e r e i n t h e r a n s f e r c y l i n d e r i n c l u d e sa l o c k i n g mechanism.

DETAILED DESCRIPTION OF THE INVENTIONR e f e r r i n g n o W t o t h e d r a W i n g s , FIGS. 1A nd 1 B shoW ana i r c r a f t l a n d i n g g e a r 1 0 , d e p i c t e d i n a d e p l o y e d a n d e x t e n d e d

p o s i t i o n i n F I G . 1 A , a n d i n c l u d i n g a s t r u t 1 1 c o n s t r u c t e d i na c c o r d a n c e W i t h t h e i n v e n t i o n . L a n d i n g g e a r 1 0 i s o f t h e t y p et h a t a t t a c h e s t o t h e s t r u c t u r e of an a i r c r a f t and s moveable

20

25

3 0

35

40

45

50

55

60

6 5

4betWeen a d e p l o y e d p o s i t i o n and a r e t r a c t e d p o s i t i o n . I n t h er e t r a c t e d p o s i t i o n l a n d i n g g e a r 1 0 i s h o u s e d W i t h i n t h e f u s el a g e o f t h e a i r c r a f t . One s k i l l e d i n t h e a r t W i l l r e a d i l y u n d e rs t a n d t h a t t h e i n v e n t i o n h e r e i n d i s c l o s e d c a n be a d a p t e d f o ru s e i n c o n j u n c t i o n With body mounted r nose mounted a n di n g g e a r . I n a d d i t i o n , t h e s h o c k s t r u t c a n be i n c l u d e d i n l a t e ra l l y r e t r a c t i n g a s W e l l a s f o r W a r d a n d a f t r e t r a c t i n g l a n d i n gg e a r c o n ? g u r a t i o n s .

I n F I G . 1 B , t h e l a n d i n g g e a r 1 0 i s shoWn n a d e p l o y e d b u ts h o r t e n e d o r s h r u n k p o s i t i o n . I n t h i s p o s i t i o n , t h e s t r u t 1 1h a s been s h o r t e n e d by a d i s t a n c e d .

R e f e r r i n g noW t o F I G S . 1 A and 1 B i n g r e a t e r d e t a i l , l a n di n g g e a r 1 0 i n c l u d e s a h y d r o p n e u m a t i c s t r u t 1 1 i n c l u d i n g as t r u t p i s t o n 1 2 h a v i n g a n u p p e r p o r t i o n t h a t i s t e l e s c o p e di n s i d e an open end of a s t r u t c y l i n d e r 1 3 . A Wheel 14 i sr o t a t a b l y mounted o a l o W e r p o r t i o n o f t h e s t r u t p i s t o n 1 2 . At r u n n i o n s h a f t 1 5 i s a t t a c h e d n o r m a l l y t o an p p e r end o r t i o nof h e s t r u t 1 1 . Eac h end of h e t r u n n i o n s h a f t 1 5 i n c l u d e s as h a ft o u r n a l t h a t s r o t a t a b l y mounted n a b u s h i n g a t t a c h e d ot h e s t r u c t u r e o f t h e a i r c r a f t . The l a n d i n g g e a r 1 0 p i v o t s a b o u tt h e a x i s o f t h e t r u n n i o n s h a f t 1 5 t o r e t r a c t f o l l o W i n g t a k e o f fa n d p i v o t s i n t h e o p p o s i t e manner o d e p l o y b e f o r e l a n d i n g t h ea i r c r a f t .A r u n n i o n c l e v i s 1 6 e x t e n d s from h e o u t e r d i a m e t e r o f h es t r u t c y l i n d e r 1 3 p r o v i d i n g a n a t t a c h m e n t p o i n t f o r a l a n d i n gg e a r a c t u a t o r 1 7 . The l a n d i n g g e a r a c t u a t o r 1 7 s pinned at ana c t u a t o r p i s t o n r o d 1 8 e x t e n d i n g from a ? r s t end t o t h e t r u nn i o n c l e v i s 1 6 . A e c o n d end f h e l a n d i n g g e a r a c t u a t o r 17 sp i n n e d t o t h e s t r u c t u r e o f t h e a i r c r a f t . H y d r a u l i c ? u i d i s p r ov i d e d by t h e a i r c r a f t t o t h e l a n d i n g g e a r a c t u a t o r 17 to d r i v et h e l a n d i n g g e a r 1 0 t o t h e r e t r a c t e d a n d d e p l o y e d p o s i t i o n s .

T o move h e l a n d i n g g e a r 1 0 f r o m t h e d e p l o y e d p o s i t i o n ot h e r e t r a c t e d p o s i t i o n , t h e l a n d i n g g e a r a c t u a t o r 17 c o mp r e s s e s , d r i v i n g t h e l a n d i n g g e a r 1 0 a b o u t t h e a x i s o f t h et r u n n i o n s h a f t 1 5 t o t h e r e t r a c t e d p o s i t i o n . B e f o r e o r d u r i n gl a n d i n g g e a r e t r a c t i o n , t h e s t r u t p i s t o n 1 2 may e d r i v e n ( b yt h e s h o c k s t r u t ) i n t o t h e s t r u t c y l i n d e r 1 3 t h e d i s t a n c e d b e f o r e t h e l a n d i n g g e a r 1 0 i s f u l l y r e f r a c t e d i n t o t h e a i r c r a f tf u s e l a g e . T h e d e t a i l s c o n c e r n i n g t h e s y s t e m f o r d r i v i n g t h es t r u t p i s t o n 1 2 i n t o t h e s t r u t c y l i n d e r 1 3 a r e p r o v i d e d b e l o W .The l a n d i n g g e a r a c t u a t o r 1 7 c o n t i n u e s t o d r i v e t h e l a n d i n gg e a r 1 0 u n t i l i t i s p o s i t i o n e d i n t h e f u l l y r e t r a c t e d p o s i t i o n .

To move l a n d i n g g e a r 1 0 from t h e r e t r a c t e d p o s i t i o n t o t h ed e p l o y e d o s i t i o n , th e l a n d i n g g e a r a c t u a t o r 1 7 e x t e n d s , d r i vi n g t h e l a n d i n g g e a r 1 0 a b o u t t h e a x i s o f t h e t r u n n i o n s h a ft 1 5t o t h e d e p l o y e d p o s i t i o n . I n i t i a l l y , a s t h e l a n d i n g g e a r 1 0d e p l o y s , t h e s t r u t p i s t o n 1 2 may e m a i n W i t h d r a W n W i t h i n t h es t r u t c y l i n d e r 1 3 . Once t h e l a n d i n g g e a r 1 0 c l e a r s t h e a i r c r a f ts u r r o u n d i n g s t r u c t u r e , t h e s t r u t p i s t o n 1 2 may e d r i v e n b y t h es h o c k s t r u t t o e x t e n d t h e s t r u t 1 1 t o i t s f u l l y e x t e n d e d l e n g t h .

T u r n i n g t o F I G . 2 , t h e s t r u t 1 1 ofFIGS. 1 A and 1 B s shoWni s o m e t r i c a l l y W i t h a t r a n s f e r c y l i n d e r 1 9 s e c u r e d t o t h e s t r u tc y l i n d e r 1 3 . The t r a n s f e r c y l i n d e r 1 9 i s i n ? u i d communicat i o n With t h e s t r u t 1 1 v i a a t r a n s f e r p o r t 20 o n t h e t r a n s f e rc y l i n d e r , t h r o u g h a ? r s t c o n d u i t 2 1 , and i n t o a t r a n s f e r i n l e tp o r t 22 on t h e s t r u t 1 1 . One a d v a n t a g e o f t h e shock s t r u t i na c c o r d a n c e W i t h t h e i n v e n t i o n i s t h a t t h e t r a n s f e r c y l i n d e r 1 9may e l o c a t e d anyWhere o n t h e l a n d i n g g e a r o r a i r c r a f t s ol o n g a s i t can maintain ?uid communication With h e s t r u t 1 1 .A e c o n d c o n d u i t ( n o t s h o W n ) p r o v i d e s ? u i d c o m m u n i c a t i o nb e t W e e n t h e t r a n s f e r c y l i n d e r 1 9 a n d t h e a i r c r a f t s h y d r a u l i cs u p p l y ( n o t s h o W n ) . A l s o shoWn n F I G . 2 i s a c o m p e n s a t o r

R e f e r r i n g noW o F I G S . 3 A and B , t h e t r a n s f e r c y l i n d e r 1 9i s shoWn i n c r o s s s e c t i o n i n tWo s t a t e s of p e r a t i o n . F I G . 3AshoWs t h e t r a n s f e r c y l i n d e r 1 9 i n a n e x t e n d e d p o s i t i o n t h a tc o r r e s p o n d s t o t h e s t r u t 11 i n an un-shrunk s t a t e . FIG. 3 B

8/13/2019 Us 8556209

13/16

US 8 , 5 5 6 , 2 0 9 B25

s h o w s t h e t r a n s f e r c y l i n d e r 1 9 i n a c o m p r e s s e d p o s i t i o n t h a tc o r r e s p o n d s t o t h e s t r u t 11 i n a shrunk and l o c k e d s t a t e .R e f e r r i n g o F I G . 3 A , t h e t r a n s f e r c y l i n d e r 1 9 i n c l u d e s a mainc y l i n d e r 3 0 f o r m i n g a c y l i n d r i c a l chamber h e r e i n . A r a n s f e rp i s t o n 3 1 i s r e c i p r o c a l l y d i s p o s e d W i t h i n t h e c y l i n d r i c a lchamber and i n c l u d e s tWo e f f e c t i v e pressure a r e a s , one o ne a c h s i d e o f t h e p i s t o n . The t r a n s f e r p i s t o n 3 1 d i v i d e s t h ec y l i n d r i c a l chamber i n t o t W o c h a m b e r s , n a m e l y , a t r a n s f e rchamber 32 and a s u p p l y chamber 3 . The t r a n s f e r chamber3 2 may b e o p e n e d t o t h e a t m o s p h e r e t h r o u g h a b l e e d o r i ? c e3 4 , t h o u g h i n o p e r a t i o n t h e t r a n s f e r chamber 3 2 i s a p a r t o f ac l o s e d h y d r a u l i c c i r c u i t a n d s ? l l e d W i t h h y d r a u l i c ? u i d . Thes u p p l y chamber 3 3 i s a p a r t o f a s e c o n d h y d r a u l i c c i r c u i t andi s ? l l e d W i t h h y d r a u l i c ? u i d p r o v i d e d b y t h e i r c r a f t s h y d r a ul i c s u p p l y . When h e h y d r a u l i c s u p p l y ? u i d s p r o v i d e d b y t h ea i r c r a f t u n d e r p r e s s u r e t o t h e s u p p l y c h a m b e r 3 3 , t h e a p p l i e dp r e s s u r e a c t s a g a i n s t t h e e f f e c t i v e p r e s s u r e a r e a o f h e t r a n s f e rp i s t o n 3 1 , u r g i n g t h e t r a n s f e r p i s t o n 3 1 t o e x p a n d t h e s u p p l ychamber 3 3 and c o n t r a c t t h e t r a n s f e r chamber 3 2 . T h i smotion d r i v e s t h e h y d r a u l i c ? u i d o u t o f t h e t r a n s f e r chamber3 2 a n d i n t o t h e c l o s e d h y d r a u l i c c i r c u i t . A p p r o p r i a t e s e a l s 3 5a r e p r o v i d e d a b o u t t h e t r a n s f e r p i s t o n 3 1 t o m a i n t a i n a s e p ar a t i o n o f t h e h y d r a u l i c ? u i d s i n t h e t r a n s f e r chamber 3 2 andt h e s u p p l y chamber 3 3 , a s c a n b e r e a d i l y a p p r e c i a t e d by o n es k i l l e d i n t h e a r t .

The r a n s f e r chamber 32 s i n ? u i d communication i t h t h es t r u t 1 1 t h r o u g h t h e c l o s e d h y d r a u l i c c i r c u i t v i a t h e t r a n s f e rp o r t 2 0 a n d a c o n d u i t 2 1 ( s e e F I G . 2 ) . As n o t e d a b o v e , Whent h e s u p p l y c h a m b e r 3 3 r e c e i v e s h y d r a u l i c ? u i d f r o m t h e a i rc r a f t h y d r a u l i c s u p p l y , t h e t r a n s f e r p i s t o n 3 1 moves t o cont r a c t t h e t r a n s f e r chamber 3 2 t h e r e b y d i s p l a c i n g a s p e c i ? cvolume o f t r a n s f e r ? u i d from t h e t r a n s f e r chamber 3 2 ,t h r o u g h t h e t r a n s f e r p o r t 2 0 and n t o t h e s t r u t 1 1 by Way f t h ec o n d u i t 2 1 . F I G . 3 B shoWs t h e t r a n s f e r c y l i n d e r 1 9 a f t e r t h et r a n s f e r p i s t o n 3 1 h a s d i s p l a c e d t h e e n t i r e volume o f t r a n s f e r? u i d from t h e t r a n s f e r chamber 3 2 .When h e t r a n s f e r p i s t o n 3 1 i s p o s i t i on e d W i t h i n t h e mainc y l i n d e r 3 0 s u c h t h a t i t h a s f u l l y d i s p l a c e d t h e v o l u m e o ft r a n s f e r ? u i d , a l o c k i n g mechanism 36 e n g a g e s t o c l o s e andl o c k t h e t r a n s f e r p i s t o n 3 1 , p r o v i d i n g a h y d r a u l i c b l o c k on h et r a n s f e r p o r t 2 0 s u c h t h a t t h e volume o f t r a n s f e r ? u i d c a n n o tr e e n t e r t h e t r a n s f er chamber 3 2 . The t r a n s f e r p i s t o n 3 1 i sc o n ? g u r e d t o c o o p e r a t e W i t h t h e l o c k i n g mechanism 3 6 t oe f f e c t t h e e n g a g e m e n t . Those s k i l l e d i n t h e a r t o f a c t u a t i o nl o c k i n g mechanisms Would be a b l e t o i n t r o d u c e s u c h a l o c ka n d t h e e x e m p l a r y s y s t e m d o e s n o t d e p e n d on a n y p a r t i c u l a rv a r i e t y .

Also shoWn i n FIGS. 3A and 3 B i s an unlock p o r t 37l o c a t e d a t a n u p p e r p o r t i o n o f t h e main c y l i n d e r 3 0 a n d a d j ac e n t t h e t r a n s f e r p o r t 2 0 . The unlock p o r t 37 s i n ?uid c o mm u n i c a t i o n W i t h t h e a i r c r a f t s h y d r a u l i c poWer s u p p l y v i a ac o n d u i t ( n o t s h o W n ) . T o u n l o c k a n d o p e n t h e t r a n s f e r p o r t 2 0 ,a v a l v e ( n o t shoWn) d i r e c t s a p r e s s u r e ( P u n l o c k ) from t h ea i r c r a f t s h y d r a u l i c s u p p l y t o t h e u n l o c k p o r t 37 o d i s p l a c e anu n l o c k i n g p i n 3 8 a n d r e le a se th e l o c k i n g mechanism 3 6 .

The s u p p l y chamber 3 i s i n ? u i d communication i t h t h ea i r c r a f t s h y d r a u l i c s u p p l y v i a a s h r i n k p o r t 3 9 , and a c o n d u i t( n o t s h o W n ) . The s h r i n k p o r t 3 9 i s l o c a t e d on a p o r t i o n o f t h em a i n c y l i n d e r 3 0 o p p o s i t e t h e t r a n s f e r p i s t o n 3 1 f r o m t h et r a n s f e r p o r t 20 s u c h t h a t t i s i n ? u i d communication i t h t h es u p p l y chamber 3 3 and n o t i n ? u i d communication W i t h t h et r a n s f e r chamber 3 2 . The t r a n s f e r p i s t o n 3 1 and s e a l s 3 5s e p a r a t e t h e t r a n s f e r chamber 2 from h e s u p p l y chamber 3s u c h t h a t t h e y a r e n o t i n ? u i d c o m m u n i c a t i o n . T h i s s e p a r a t i o np r e v e n t s t h e volume f r a n s f e r ? u i d f r o m e n t e r i n g a n d f f e c t

20

25

3 0

40

45

50

55

60

6 5

6i n g th e a i r c r a f t s h y d r a u l i c p o W e r s u p p l y a n d p r e v e n t s t h eh y d r a u l i c p o W e r s u p p l y f r o m a f f e c t i n g t h e c l o s e d h y d r a u l i cc i r c u i t of h e shock t r u t .

I n o p e r a t i o n , t h e t r a n s f e r c y l i n d e r 1 9 r e s p o n d s t o a r e l at i v e l y h i g h p r e s s u r e a n d l o W ?oW a t e h y d r a u l i c ? u i d i n p u tfrom t h e a i r c r a f t s h y d r a u l i c s y s t e m t o t r a n s f e r o r p r o v i d e al o W e r p r e s s u r e a n d h i g h e r ? o W r a t e h y d r a u l i c ? u i d o u t p u t t ot h e s t r u t 1 1 t o r e d u c e t h e l e n g t h o f t h e s t r u t 1 1 . The a i r c r a f t sh y d r a u l i c s u p p l y a p p l i e s a p r e s s u r e ( P s u p p l y ) a t t h e s h r i n kp o r t 3 9 a n d h y d r a u l i c ? u i d e n t e r s i n t o t h e s u p p l y chamber 3 .Wh e n t h e e f f e c t i v e f o r c e a p p l i e d t o t h e p i s t o n 3 1 from t h es u p p l y chamber 3 ( P s u p p l y ) i s g r e a t e r t h a n a n e f f e c t i v e f o r c ea p p l i e d t o t h e p i s t o n 3 1 f r o m t h e t r a n s f e r chamber 3 2( P s h r i n k ) , t h e t r a n s f er p i s t o n 3 1 moves t o i n c r e a s e t h e s i Z e o ft h e s u p p l y chamber 3 3 and c o n t r a c t t h e s i Z e o f t h e t r a n s f e rchamber 3 2 , t h e r e b y d i s p l a c i n g a volume o f t r a n s f e r ? u i dt h r o u g h t h e t r a n s f e r p o r t 2 0 and n t o t h e s t r u t 1 1 t o s h r i n k t f o rr e t r c t i o n i n t o t h e f u s e l a g e .When th e l a n d i n g g e a r i s a g a i n d e p l o y e d , th e a i r c r a f t sh y d r a u l i c s u p p l y may r e d u c e t h e p r e s s u r e a p p l i e d a t t h es h r i n k p o r t 3 9 ( n o W P r e t u m ) a n d a p p l i e s a n u n l o c k p r e s s u r e tt h e u n l o c k p o r t 3 7 ( P u n l o c k ) c a u s i n g t h e l o c k i n g m e c h a n i s m3 6 t o r e l e a s e , t h e r e b y r e m o v i n g t h e h y d r a u l i c b l o c k on ? o Wt h r o u g h t r a n s f e r p o r t 2 0 . I f t h e r e d u c e d p r e s s u r e a p p l i e d t t h es h r i n k p o r t 39 ( P r e t u m ) r e s u l t s i n an e f f e c t i v e f o r c e o n t h ep i s t o n 3 1 t h a t i s b e l o W t h e e f f e c t i v e f o r c e a p p l i e d b y a p r e ss u r e i n t h e c l o s e d h y d r a u l i c c i r c u i t ( P g a s ) , t h e n t h e volume o ft r a n s f e r ?uid W i l l r e t u r n t o t h e t r a n s f e r chamber 32 v i a t h et r a n s f e r p o r t 2 0 a n d r e t u r n t h e t r a n s f e r p i s t o n 3 1 t o i t s o r i g i n a lp o s i t i o n . The p r e s s u r e s ( P r e t u m ) a n d ( P g a s ) a re d i s c u s s e dbeloW With r e f e r e n c e t o F I G . 6 .

T u r n i n g noW t o F I G . 4 , a c r o s s - s e c t i o n o f t h e s t r u t 1 1 i sshoWn n a f u l l y extended p o s i t i o n a s i s t h e c a s e a f t e r t a k e o f fb u t p r i o r t o r e t r a c t i o n . As c a n b e s e e n , t h e t r a n s f e r c y l i n d e r 1 9(shoWn s e c u r e d t o t h e s t r u t 1 1 ) i s i n an e x t e n d e d state i n d ic a t i n g t h a t t h e volume o f t r a n s f e r ? u i d r e s i d e s i n t h e t r a n s f e rchamber 3 2 . The s t r u t p i s t o n 1 2 i s r e c i p r o c a l l y r e c e i v e dW i t h i n t h e s t r u t c y l i n d e r 1 3 i n a c o n c e n t r i c r e l a t i o n s h i p W i t hand betWeen t h e s t r u t c y l i n d e r 1 3 and a n o r i ? c e s u p p o r t t u b e4 0 . A o W e r s t r u t b e a r i n g 4 1 i s r e c e i v e d W i t h i n t h e open end ft h e s t r u t c y l i n d e r 1 3 a g a i n s t Which t h e s t r u t p i s t o n 1 2 s l i d e s .An p p e r s t r u t b e a r i n g 4 2 i s a t t a c h e d o t h e end o r t i o n o f h es t r u t p i s t o n 1 2 W i t h i n t h e s t r u t c y l i n d e r 1 3 s l i d i n g a g a i n s t i t si n t e r i o r . A a s s p r i n g chamber 3 i s formed i t h i n t h e i n t e r i o rs e c t i o n o f h e c y l i n d e r 1 3 , p i s t o n 1 2 , a n d c a p p e d b y t h e l o W e rs t r u t b e a r i n g 4 1 . The g a s s p r i n g c h a m b e r 4 3 i s p r e s s u r i z e dW i t h g a s a t a p r e s s u r e ( P g a s ) , Which v a r i e s W i t h t h e t e m p e r at u r e and e g r e e o f n s e r t i o n o f t h e s t r u t p i s t o n 1 2 i n t o t h e s t r u tc y l i n d e r 1 3 . A h r i n k p i s t o n 44 and a s e t of s p a c e r s 45 a r ed i s p o s e d b e t W e e n t h e i n t e r i o r b o r e o f h e s t r u t c y l i n d e r 1 3 , t h es t r u t p i s t o n 1 2 , t h e u p p e r s t r u t b e a r i n g 4 2 , a n d t h e l o W e r s t r u tb e a r i n g 4 1 , a l l o W i n g t h e s t r u t p i s t o n 1 2 t o e x t e n d a p r e d e t e rmined i s t a n c e . At u l l s t r u t e x t e n s i o n , t h e u p p e r s t r u t b e a r i n g4 2 , s h r i n k p i s t o n 4 4 , a s e t o f s p a c e r s 4 5 , and l o W e r s t r u tb e a r i n g 4 1 a r e f o r c e d i n t o c o n t a c t due to t h e b i a s c a u s e d byt h e g a s p r e s s u r e ( P g a s ) W i t h i n t h e g a s s p r i n g chamber 3 .A t r u t s h r i n k chamber 46 i s formed betWeen t h e s h r i n k

p i s t o n 4 4 , th e s t r u t c y l i n d e r 1 3 , th e s t r u t p i s t o n 1 2 , a n d t h el o W e r b e a r i n g 4 1 . The s t r u t s h r i n k chamber 46 i s i n ? u i dcommunication W i t h t h e t r a n s f e r i n l e t p o r t 2 2 and i s ? l l e dW i t h h y d r a u l i c ? u i d . I n F I G . 4 t h e s t r u t 1 1 i s shoWn n s h r u n k .I n t h is s t a t e , t h e s h r i n k chamber 46 h a s a minimum volume.The s h r i n k chamber 46 i s i n ? u i d communication W i t h t h et r a n s f e r chamber 3 2 o f t h e t r a n s f e r c y l i n d e r 1 9 v i a a c o n d u i t2 1 ( s h o W n s c h e m a t i c a l l y ) a n d t h e volume o f t r a n s f e r ? u i dmay be t r a n s f e r r e d from h e t r a n s f e r chamber 3 2 t o t h e s h r i n kchamber 46 When t h e t r a n s f e r chamber f o r c e o n t h e s h r i n k

8/13/2019 Us 8556209

14/16

US 8 , 5 5 6 , 2 0 9 B27

p i s t o n 4 4 e x c e e d s t h e f o r c e a p p l i e d o t h e o p p o s i t e s i d e o f t h es h r i n k p i s t o n 4 4 ( r e s u l t i n g f r o m P g a s a n d o t h e r e x t e r n a l l ya p p l i e d f o r c e s ) .The g a s s p r i n g p r e s s u r e o f t h e s t r u t 1 1 v a r i e s W i t h t h ec o m p r e s s i o n o f t h e p i s t o n 1 2 i n t o t h e c y l i n d e r 1 3 , a s i n t h ec a s e W h e n h e a i r c r a f t l a n d s o r s t a x i i n g a c r o s s t h e a i r ? e l d . I ns u c h a c a s e , t h e p r e s s u r i z e d g a s i n t h e g a s s p r i n g chamber 3i s f u r t h e r compressed s t h e s t r u t 1 1 a b s o r b s t h e e n e r g y of h el o a d s e x e r t e d upon t . The s h r i n k p i s t o n 4 4 may r e m a i n i nc o n t a c t With t h e l o W e r s t r u t b e a r i n g 41 and a rebound c h amb e r 47 s e s t a b l i s h e d betWeen t h e u p p e r s t r u t b e a r i n g 42 andt h e s h r i n k p i s t o n 4 4 . As t h e s t r u t p i s t o n 1 2 a g a i n e x t e n d s , t h e? u i d i n t h e r e b o u n d chamber 47 s l o W s t h e p i s t o n 1 2 e x t e n s i o nr a t e W i t h i n c r e a s e d p r e s s u r e Which i s e x e r t e d a g a i n s t t h es h r i n k p i s t o n 4 4 k e e p i n g i t i n c o n t a c t W i t h t h e l o W e r b e a r i n g4 1 .

T u r n i n g t o F I G S . 5A and 5 B , d e t a i l e d c r o s s - s e c t i o n a lvieWs o f t h e s t r u t 1 1 a r e shoWn i n tWo s t a t e s : unshrunk ( F I G .5 A ) a n d s h r u n k ( F I G . 5 B ) . I n F I G . 5 A , t h e s h r i n k p i s t o n 4 4 i sshoWn d i s p o s e d b e t W e e n t h e l o W e r b e a r i n g 4 1 a n d t h erebound chamber 4 7 . I n r e s p o n s e t o t h e movement of t h et ra n s f e r p i s t o n 1 , t h e v o l u m e o f y d r a u l i c ? u i d n t h e t ra n s f e rchamber 3 2 ?oWs t h r o u g h t h e t r a n s f e r i n l e t p o r t 2 2 i n t o t h es t r u t s h r i n k chamber 6 . The ?uid r e s s u r e i n t h e s t r u t s h r i n kchamber 6 i s s u ? i c i e n t t o f o r c e t h e s h r i n k p i s t o n 4 4 , s p a c e r s4 5 , u p p e r s t r u t b e a r i n g 4 2 , and t r u t p i s t o n 1 2 t o W i t h d r a W i n t ot h e s t r u t c y l i n d e r 1 3 a d i s t a n c e d .

F I G . 5B i l l u s t r a t e s a f u l l y s h r u n k s t a t e Wherein t h e s h r i n kchamber 4 6 h a s expanded t o accommodate t h e volume o ft r a n s f e r ? u i d t r a n s f e r r e d from t h e t r a n s f e r chamber 3 2 . Asm e n t i o n e d p r e v i o u s l y , o n c e t h e t r a n s f e r p i s t o n 3 1 h a s d i sp l a c e d th e v o l u m e o f ? u i d f r o m th e t r a n s f e r c h a m b e r 3 2 , t h el o c k i n g m e c h a n i s m 3 6 i s e n g a g e d t h u s l o c k i n g r a n s f e r p i s t o n3 1 Which b l o c k s ? o W t h r o u g h t r a n s f e r p o r t 2 0 s u c h t h a t t h evolume o f t r a n s f e r ? u i d i s h y d r a u l i c a l l y l o c k e d i n t h es h r i n k chamber 4 6 .

Turning noW o FIG. 6 , a c o n t r o l device su c h a s an exemp l a r y a i r c r a f t s e q u e n c e v a l v e 6 0 commands t h e a i r c r a f t sh y d r a u l i c s u p p l y t o ( l ) s h r i n k t h e s t r u t 1 1 a n d i n d e p e n d e n t l y( 2 ) r e t r a c t t h e l a n d i n g g e a r 1 0 . The s e q u e n c e v a l v e 6 0 Whichd i r e c t s h y d r a u l i c s u p p l y p r e s s u r e and r e t u r n p r e s s u r e t o t h et r a n s f e r c y l i n d e r 1 9 i s i n ? u i d c o m m u n i c a t i o n W i t h t h e s u p p l ychamber 3 3 o f t h e t r a n s f e r c y l i n d e r 1 9 t h r o u g h a c o n d u i t 6 1a n d s u p p l y p o r t 3 9 . The s e q u e n c e v a l v e 6 0 i s a l s o i n ? u i dcommunication W i t h t h e l o c k i n g mechanism 3 6 t h r o u g h ac o n d u i t 6 2 and n l o c k p o r t 3 7 . As o t e d a b o v e , t h e c o n d u i t 2 1p r o v i d e s ? u i d communica tion betWeen h e s t r u t s h r i n k chamb e r 4 6 a n d t h e t r a n s f e r chamber 2 . An p p r o p r i a te h y d r a u l i cs u p p l y s y s t e m n o t s h o W n ) i n c l u d i n g , f o r e x a m p l e , a h y d r a ul i c pump a n d ? u i d r e s e r v o i r , i s n e c e s s a r y t o s u p p l y t h es e q u e n c e v a l v e 6 0 . While h e example o f s e q u e n c e v a l v e 6 0 i sshoWn and d e s c r i b e d , c o n t r o l d e v i c e s a r e W e l l k n o Wn i n t h ea r t and t h e i n v e n t i o n i s n o t dependent o n t h e use of anyp a r t i c u l a r c o n t r o l d e v i c e .

I n a c c o r d a n c e W i t h t h e i n v e n t i o n , t h e shock s t r u t i s cont r o l l e d i n d e p e n d e n t l y o f t h e l a n d i n g g e a r a c t u a t o r 1 7 . I t i sn o t e d , h o W e v e r , t h a t t h e s e q u e n c e v a l v e 6 0 may o p e r a t e t h es h o c k s t r u t d e s c r i b e d h e r e i n b e f o r e o r d u r i n g l a n d i n g g e a rr e t r a c t i o n a n d may e t u r n t h e s t r u t t o i t s o r i g i n a l l e n g t h d u r i n go r a f t e r l a n d i n g g e a r d e p l o y m e n t .

A p p l y i n g a n u m e r i c a l example o t h e s c h e m a t i c i n F I G . 6 ,a n a i r c r a f t h y d r a u l i c s u p p l y may b e p r o v i d e d a t a r e l a t i v e l yh i g h p r e s s u r e ( e . g . , 4 0 0 0 p s i ) b u t W i t h a r e l a t i v e l y l o W ? oWr a t e ( e . g . , 3 . 0 GPM v a i l a b l e . Such a loW ? o W r a t e may n o tp r o v i d e t h e volume f ? o W e q u i r e d o ? l l t h e s h r i n k chamber46 o f t h e s t r u t 1 1 i n a g i v e n p e r i o d o f t i m e betWeen h e p i l o t si n p u t a n d th e l a n d i n g g e a r s r e t r a c t i o n i n t o t h e f u s e l a g e o f t h e

20

25

3 0

35

40

45

50

55

60

6 5

8a i r c r a f t . W h e n , h o W e v e r , t h e h i g h s u p p l y p r e s s u r e s p r o v i d e dt o t h e t r a n s f e r c y l i n d e r 1 9 , i t a c t s o n s m a l l e f f e c t i v e p r e s s u r ea r e a o f t h e t r a n s f e r p i s t o n 3 1 . The o p p o s i n g s i d e o f t h e t r a n sf e r p i s t o n 3 1 h a s a mu c h a r g e r e f f e c t i v e a r e a andiWhen h ep i s t o n 3 1 i s i n motioniit d r i v e s a muc h l a r g e r t r a n s f e r ? u i d? o W a t e ( e . g . , 6 . 5 GPM e r l a n d i n g gearil3 GPM o r l e f ta n d r i g h t l a n d i n g g e a r ) f r o m t h e t r a n s f e r chamber 3 2 a t al o W e r p r e s s u r e ( e . g . , l e s s t h a n 2 0 0 0 p s i ) . F o r r e t u r n i n g t h es t r u t 1 1 t o i t s unshrunk o r extended l e n g t h , t h e a i r c r a f tsequence v a l v e 60 e n s u r e s t h a t t h e s u p p l y s h r i n k p r e s s u r e( P s u p p l y ) i s removed o r r e d u c e d ( P r e t u r n ) , a n d f u r t h e ra p p l i e s a n u n l o c k i n g p r e s su r e ( P u n l o c k ) v i a c o n d u i t 6 2 t o t h eu n l o c k p o r t 3 7 . T h i s c o m b i n a t i o n o f n p u t s o p e r a t e s t o r e l e a s et h e l o c k i n g mechanism 6 a n d u n b l o c k ? o W t h r o u g h t r a n s f e rp o r t 2 0 t o a l l o W t h e g a s s p r i n g p r e s s u r e ( P g a s ) o f t h e s t r u t t od r i v e t he s h r i n k p i s t o n 44 t o c o n t r a c t t h e s h r i n k chamber 4 6and e t u r n t h e volume of r a n s f e r ?uid o t h e t r a n s f e r chamber3 2 .

The shock s t r u t i n accordance With t h e i n v e n t i o n r e l i e s o nt r a n s f e r r i n g a s p e c i ? c volume f r a n s f e r ? u i d from h e t r a n sf e r chamber 32 to t h e s h r i n k chamber 6 . C o m p r e s s i b i l i t y andi n - s e r v i c e t e m p e r a t u r e v a r i a t i o n s may a f f e c t t h e e f f e c t i v e? u i d volume i n t h e s y s t e m . To c o m p e n s a t e f o r s u c h ? u c t u at i o n s , t h e c o m p e n s a t o r 2 3 i s a d d e d t o t h e s y s t e m s h y d r a u l i cs c h e m a t i c shoWn n F I G . 6 . The compensator 2 3 p r o v i d e s a na d d i t i o n a l volume f ? u i d t o t h e s y s t e m t o compensate o r t h ef a c t o r s l i s t e d above and f u r t h e r m a i n t a i n s a nominal p r e s s u r eo n t h e ?uid i n t h e c o n d u i t s of t h e s y s t e m and p r o v i d e s ani n d i c a t i o n When h e ? u i d l e v e l i n t h e s y s t e m becomes loW andm a i n t e n a n c e i s r e q u i r e d .

T u r n i n g t o F I G S . 7 A a n d 7 B , a n e x e m p l ar y c o m p e n s a t o r2 3 i s shoWn i n c r o s s - s e c t i o n i n tWo states o f o p e r a t i o n . F I G .7 A s h o W s t h e c o m p e n s a t o r 2 3 When t i s f u l l o f h y d r a u l i c? u i d . F I G . 7 B shoWs t h e compensator 3 When h e shock t r u ti s loW o n y d r a u l i c ? u i d . The compensator 2 3 i n c l u d e s a mainc y l i n d e r 7 0 h a t f o r m s a c y l i n d r i c a l c a v i t y h a v i n g t W o e n d s . Ata ? r s t end of h e c a v i t y i s a ?uid chamber 71 t h a t i s i n ? u i dcommunication W i t h t h e shock t r u t s h y d r a u l i c c i r c u i t v i a ap o r t 7 2 . BetWeen h e ?uid chamber 71 and second end of h ec y l i n d r i c a l c a v i t y i s a p i s t o n 7 3 t h a t m a i n t a i n s a s e a l a g a i n s tan i n t e r i o r W a l l o f t h e c y l i n d r i c a l c a v i t y . On s i d e o f t h ep i s t o n 7 3 o p p o s i t e t h e ? u i d c h a m b e r 7 1 i s a s p r i n g 7 4 e x e r t i n ga p r e l o a d e d b i a s f o r c e a g a i n s t p i s t o n 7 3 f o r m a i n t a i n i n g anominal p r e s s u r e on t h e ?uid i n t h e ?uid chamber 7 1 . I n t h ee x a m p l e shoWn t h e s p r i n g i s a m e c h a n i c a l c o i l s p r i n g . Anys p r i n g , h o W e v e r , t h a t p r o v i d e s a b i a s f o r c e a g a i n s t t h e p i s t o n73 and h u s a p r e s s u r e i n t h e ?uid n t h e ?uid chamber 1 maybe u s e d . Examples i n c l u d e a compressed g a s s p r i n g o r ad i f f e r e n t m e c h a n i c a l s p r i n g c o n ? g u r a t i o n .

I n t h e e x a m p l e shoWn n F I G S . 7 A a n d 7 B , t h e compensat o r 23 a l s o i n c l u d e s a loW ?uid v i s u a l i n d i c a t o r 75 by Way ofa d d i n g a n e x t e n s i o n 7 6 t o t h e p i s t o n 7 3 t h a t e x t e n d s t h r o u g han r i ? c e 77 t t h e ? r s t end o f t h e c y l i n d r i c a l c a v i t y When h es p r i n g 7 4 p u s h e s t h e p i s t o n 7 3 t h r o u g h th e ? u i d c h a m b e r 7 1 .The p r e s e n c e o f t h e i n d i c a t o r 7 5 t h r o u g h t h e o r i ? c e 77 i n d ic a t e s t h a t t h e ? u i d chamber 7 1 i s m a r g i n a l l y ? l l e d o r e m p t y .T h i s v i s u a l i n d i c a t i o n p r o v i d e s t h e a i r c r a f t m a i n t e n a n c e creWa simple check a s t o Whether t h e shock s t r u t has l o s t ?uid o ro t h e r W i s e r e q u i r e s m a i n t e n a n c e . A e n s o r c o u l d a l s o be addedt o p r o v i d e an l e c t r o n i c i n d i c a t i o n t o a maintenance computera l o n g W i t h ( o r i n s t e a d o f ) th e v i s u a l i n d i c a t i o n .

With r e g a r d s t o F I G S . 8 A , 8B a n d 9 , t h e f e a t u r e s o f t h el a n d i n g g e a r 10 a r e t h e same a s d e s c r i b e d above With t h ee x c e p t i o n o f t h e h y d r a u l i c - p o W e r e d t r a n s f e r c y l i n d e r 1 9c o u p l e d t o t h e s t r u t 1 1 . A c c o r d i n g l y , t h e r e f e r e n c e n u m e r a l sf o r t h e l a n d i n g g e a r components remain t h e same W h i l e neW

8/13/2019 Us 8556209

15/16

US 8 , 5 5 6 , 2 0 9 B29

r e f e r e n c e n u m e r a l s h a v e b e e n p r o v i d e d f o r a n e l e c t r i c - p o We r e d t r a n s f e r c y l i n d e r d e s c r i b e d h e r e i n a f t e r .

FIGS. 8A and 8B s h o w an embodiment of an e l e c t r i cp o W e r e d r a n s f e r c y l i n d e r 0 0 t h a t may e p l a c e th e p r e v i o u s l yd e s c r i b e d h y d r a u l i c - p o W e r e d t r a n s f e r c y l i n d e r 1 9 . F I G . 8AshoWs t h e t r a n s f e r c y l i n d e r 1 0 0 i n a n e x t e n d e d p o s i t i o n t h a tc o r r e s p o n d s t o t h e s t r u t 1 1 i n an un-shrunk s t a t e . FIG. 8Bs h o W s t h e t r a n s f e r c y l i n d e r 1 0 0 i n a c o m p r e s s e d p o s i t i o n h a tcorresponds t o t h e s t r u t 1 1 i n a shrunk o r locked s t a t e .

R e f e r r i n g p r i m a r i l y o F I G . 8 B , t h e e l e c t r i c - p o W e r e d r a n sf e r c y l i n d e r 1 0 0 i n c l u d e s a m e c h a n i c a l a c t u a t i o n s y s t e m 102con?gured t o move an amount o f t r a n s f e r ?uid 104 from at r a n s f e r chamber 06 o t h e s t r u t 1 . I n t h e i l l u s t r a t e d embodim e n t , t h e mechanical a c t u a t i o n system 102 i n c l u d e s a motor1 0 8 , a motor gearbox 1 0 , a b a l l n u t 1 1 2 , and b a l l screW 114c o u p l e d t o a p i st o n 1 1 6 . I t i s a p p r e c i a t e d , h o W e v e r , t h a t t h a tt h e i l l u s t r a t e d m e c h a n i c a l a c t u a t i o n s y s t e m 1 0 2 i s e x e m p l a r ya n d t h a t o t h e r t y p e s o f m e c h a n i c a l i . e . , n o n - h y d r a u l i c - p o We r e d ) a c t u a t i o n s y s t e m s f o r moving th e t r a n s f e r ? u i d mayi n c l u d e d i f f e r e n t components o r s i m i l a r componentsa r r a n g e d i n a d i f f e r e n t c o n ? g u r a t i o n .

The motor 108 may t a k e t h e form of an e l e c t r i c motorh a v i n g a s u ? i c i e n t amount of poWer t o s h r i n k t h e s t r u t 1 1 bya d e s i r e d l e n g t h W i t h i n a d e s i r e d t i m e , such a s W i t h i n feWseconds o r l e s s . I n one embodiment, t h e motor i s s i Z e d t os t r o k e t h e b a l l s c r e W 114 t h r o u g h i t s f u l l t r a v e l i n a b o u t 1 . 2 t oa b o u t . 5 s e c o n d s When n e r g i Z e d W i t h l e c t r i c a l poWer fromt h e a i r c r a f t W h i l e a p r e s s u r e of t h e t r a n s f e r ?uid 104 r i s e sa p p r o x i m a t e l y i n e a r l y f r o m a b o u t 6 5 0 p s i g o a b o u t 8 6 5 p s i g .

The motor 108 s c o u p l e d t o t h e b a l l s c r e W 114 by Way o ft h e m o t o r g e a r box 1 1 0 b e i n g m e c h a n i c a l l y e n g a g e d t o t h eb a l l n u t 1 1 2 . The motor 108 t h e r e f o r e o p e r a t e s t o r o t a t e t h eb a l l n u t 1 1 2 , Which i s engaged W i t h t h e b a l l s c r e W 1 1 4 .G e n e r a l l y , a b a l l screW c o n v e r t s r o t a t i o n a l motion i n t o h o r iZ o n t a l m o t i o n . The b a l l screW 114 may a k e t h e form of ar o t a t i n g s h a f t W i t h a h e l i c a l g r o o v e s formed h e r e o n . The a l ln u t 112 ma y n c l u d e i n t e r n a l g r o o v e s W i t h b a l l b e a r i n g s con?gured t o engage t h e h e l i c a l g r o o v e s of h e b a l l s c r e W . Them o t i o n o f t h e b a l l s c r e W may e c l o s e l y c o n t r o l l e d by s e l e c ti n g d e s i r e d m a n u f a c t u r i n g t o l e r a n c e s . I n t h e i l l u s t r a t e dembodiment, t h e p i s t o n 116 i s p o s i t i o n e d on o n e end o f t h eb a l l s c r e W 1 1 4 and s e a l a b l y movable W i t h i n a c y l i n d e r body1 1 7 o f t h e t r a n s f e r c y l i n d e r 1 0 0 . The p i s t o n 1 1 6 may b ei n t e g r a l l y machined W i t h t h e m a n u f a c t u r e o f t h e b a l l s c r e W114 and h u s r o t a t e W i t h t h e b a l l s c r e W 1 1 4 . A l t e r n a t i v e l y , t h ep i s t o n 1 1 6 may e r o t a t i o n a l l y d e - c o u p l e d from h e a l l s c r e W114 s u c h t h a t t h e p i s t o n 1 1 6 d o e s n o t r o t a t e W i t h b a l l s c r e W1 1 4 .

D u r i n g o p e r a t i o n , th e t r a n s f e r c y l i n d e r 1 0 0 o p e r a t e s t opush a d e s i r e d volume of r a n s f e r ?uid 104 i n t o t h e s t r u t 1 1and h e n l o c k s t o h o l d t h e ? u i d 104 i n t h e s t r u t 1 1 . Locking o ft h e t r a n s f e r c y l i n d e r 1 0 0 may b e a c h i e v e d h y d r a u l i c a l l y ,d e s c r i b e d h e r e i n and shoWn i n F I G . 8 B , o r m e c h a n i c a l l y ,describedbeloW and shoWn n F I G . 9 . I n one embodiment, t h et r a n s f e r c y l i n d e r 1 0 0 i n c l u d e s a h y d r a u l i c l o c k mechanism118 h a v i n g a h y d r a u l i c b l o c k v a l v e 120 and h y d r a u l i c b l o c ks e n s o r 1 2 2 , b o t h s c h e m a t i c a l l y i l l u s t r a t e d i n F I G . 8B and o t hl o c a t e d o n an upper p o r t i o n o f t h e t r a n s f e r c y l i n d er 1 0 0 . Thev a l v e 1 2 0 may e a c t u a t e d b y t h e p i s t o n 1 1 6 t o h y d r a u l i c a l l yblock t h e t r a n s f e r ?uid 104 i n t h e s t r u t 1 1 o r t o l o c k t h e b a l lscreW 114 from s t r o k i n g . The s e n s o r 122 may r o v i d e ani n d i c a t i o n o f t h e b l o c k e d c o n d i t i o n a n d / o r t h e l o c k e d c o n d it i o n and may a l s o p r o v i d e a n i n d i c a t i o n o f t h e mechanismu s e d t o c r e a t e t h e l o c k e d c o n d i t i o n . By Way o f e x a m p l e , t h es e n s o r 122 may a k e t h e form of a SIMPLEX a l l E f f e c ts e n s o r . A e s t r i c t o r ( n o t shoWn) may be u s e d t o c o n t r o l t h et i m e i t t a k e s f o r t h e ? u i d 104 t o be pushed i n t o t h e s t r u t 1 1 .

20

25

3 0

35

40

45

50

55

60

6 5

1 0F I G . 9 shoWs a n o n - h y d r a u l i c mechanism f o r l o c k i n g t h et r a n s f e r c y l i n d e r 1 0 0 , s p e c i ? c a l l y a m e c h a n i c a l l o c k i n g

mechanism 1 2 4 . I n one e m b o d i m e n t , t h e m e c h a n i c a l l o c k i n gmechanism 1 2 4 i n c l u d e s a s o l e n o i d 1 2 6 s e l e c t i v e l y o p e r a b l et o move p i n , l i n k , cam o r o t h e r d e v i c e 128 i n t o a l o c k i n ge n g a g e m e n t W i t h t h e b a l l n u t 1 1 2 . By Way o f e x a m p l e , t h es o l e n o i d 126 may be e n e r g i Z e d t o p i v o t t h e l i n k 128 i n t o al o c k i n g e n g a g e m e n t W i t h t h e b a l l n u t 1 1 2 .A p r i n g l o a d e d c o m p e n s a t o r n o t s h o W n ) may e p r o v i d e dt o s t o r e a d e s i r e d volume of r a n s f e r ?uid and t o maintain t h e? u i d p r e s s u r e W i t h i n a d e s i r e d r a n g e . By Way o f e x a m p l e , t h ecompensator may e con?gured o m a i n t a i n t h e ? u i d p r e s s u r ebetWeen a b o u t 5 0 p s i g a t a loW ? u i d l e v e l and a b o u t 1 0 0 p s i ga t a f u l l ? u i d l e v e l . P e r i o d i c b l e e d i n g o f t h e t r a n s f e r c y l i n d e r100 may be n e c e s s a r y and d u r i n g s u c h a p r o c e d u r e t h e c o mp e n s a t o r s p r e f e r a b l e f u l l y c o m p r e s s e d . I n o n e e m b o d i m e n t ,b l e e d i n g o f th e t r a n s f e r c y l i n d e r 1 0 0 may b e a c c o m p l i s h e dWith a t o o l o r p r e f e r a b l e through t h e u s e o f p r e s s u r e . I t i sf u r t h e r n o t e d t h a t th e e x e m p l a r y c o m p e n s a t o r s may e p a c ka g e d a n d l o c a t e d a n y W h e r e i n th e a i r c r a f t , th e t r a n s f e r c y l i nd e r s 19 o r 1 0 0 , o r t h e s t r u t 1 1 .

A l t h o u g h t h e i n v e n t i o n h a s b e e n shoWn n d d e s c r i b e d W i t hr e s p e c t t o a c e r t a i n p r e f e r r e d embodiment o r embodiments, ti s o b v i o u s t h a t e q u i v a l e n t a l t e r a t i o n s and m o d i ? c a t i o n s W i l lo c c u r to o t h e r s s k i l l e d i n t h e a r t upon t h e r e a d i n g and unders t a n d i n g o f t h i s s p e c i ? c a t i o n a n d th e a n n e x e d d r a W i n g s . I np a r t i c u l a r r e g a r d t o the v a r i o u s f u n c t i o n s p e r f o r m e d b y t h ea b o v e d e s c r i b e d e l e m e n t s ( c o m p o n e n t s , a s s e m b l i e s , d e v i c e s ,c o m p o s i t i o n s , e t c . ) , t h e t e r m s ( i n c l u d i n g a r e f e r e n c e t o ameans) used t o d e s c r i b e such e l e m e n t s a r e i n t e n d e d t oc o r r e s p o n d , u n l e s s o t h e r W i s e i n d i c a t e d , t o a n y e l e m e n t Whichp e r f o r m s t h e s p e c i ? e d f u n c t i o n o f h e d e s c r i b e d e l e m e n t i . e . ,t h a t i s f u n c t i o n a l l y e q u i v a l e n t ) , e v e n t h o u g h n o t s t r u c t u r a l l ye q u i v a l e n t o t h e d i s c l o s e d s t r u c t u r e W h i c h p e r f o r m s t h e f u n ct i o n i n t h e h e r e i n i l l u s t r a t e d e x e m p l a r y embodiment o rembodiments o f t h e i n v e n t i o n . I n a d d i t i o n , W h i l e a p a r t i c u l a rf e a t u r e o f t h e i n v e n t i o n may h a v e been d e s c r i b e d above W i t hr e s p e c t t o only one o r more of s e v e r a l i l l u s t r a t e d embodiments, such f e a t u r e may e combined With one o r more o t h e rf e a t u r e s o f t h e o t h e r embodiments, a s may b e d e s i r e d anda d v a n t a g e o u s f o r a n y g i v e n o r p a r t i c u l a r a p p l i c a t i o n .

The embodiments o f t h e i n v e n t i o n i n Which an e x c l u s i v ep r o p e r t y o r p r i v i l e g e i s claimed a r e de?ned a s f o l l o W s :

1 A r a n s f e r c y l i n d e r f o r a s h o ck s t r u t of an a i r c r a f t landingg e a r s y s t e m , t h e t r a n s f e r c y l i n d e r c o m p r i s i n g :

a c y l i n d e r body h a v i n g a t r a n s f e r ? u i d chamber i n ? u i dcommunication W i t h t h e s h o c k s t r u t ;

a p i s t o n s e a l a b l y m o v a b l e W i t h i n t h e c y l i n d e r b o d y ;a n o n - h y d r a u l i c a l l y a c t u a te d d e v i c e c o u p l e d t o t h e p i s t o n ,

t h e d e v i c e o p e r a b l e to move t h e p i s t o n betWeen a ? r s tp o s i t i o n a n d a s e c o n d p o s i t i o n W i t h i n t h e c y l i n d e r b o d y ;

a motor p e r a b l y c o u p l e d t o t h e d e v i c e , W h e r e i n t h e motori s e n e r g i Z a b l e by a n e l e c t r i c s y s t e m o f t h e a i r c r a f t .2 . The t r a n s f e r c y l i n d e r a c c o r d i n g t o c l a i m 1 , W h e r e i n t h e

p i s t o n s i n t e g r a l l y f o r m e d W i t h th e d e v i c e .3 . The t r a n s f e r c y l i n d e r a c c o r d i n g t o c l a i m 1 , W h e r e i n t h edevice i n c l u d e s a b a l l n u t engaged With a b a l l s c r e W .4 . The t r a n s f e r c y l i n d e r a c c o r d i n g t o c l a i m 1 , W h e r e i n t h em otor s an e l e c t r i c motor.5 . The t r a n s f e r c y l i n d e r a c c o r d i n g t o c l a i m 1 , f u r t h e r comp r i s i n g a g e a r box engaged W i t h t h e motor and t h e d e v i c e .6 . The t r a n s f e r c y l i n d e r a c c o r d i n g t o c l a i m 1 , f u r t h e r comp r i s i n g a l o c k i n g mechanism a c t u a t a b l e b y t h e p i s t o n t o l o c kt h e p i s t o n i n a d e s i r e d p o s i t i o n .7 . The t r a n s f e r c y l i n d e r a c c o r d i n g t o c l a i m 6 , W h e r e i n t h el o c k i n g mechanism i n c l u d e s a block v a l v e and a s e n s o r p o s it i o n e d on a n upper p o r t i o n o f t h e t r a n s f e r c y l i n d e r .

8/13/2019 Us 8556209

16/16

US 8 , 5 5 6 , 2 0 9 B21 1

8 . The r a n s f e r c y l i n d e r a c c o r d i n g t o c l a i m 1 , f u r t h e r comp r i s i n g a n e l e c t r i c a l l y a c t u a t e d l o c k i n g m e c h a n i s m o p e r a b l eto l o c k t h e d e v i c e i n a d e s i r e d p o s i t i o n .9 . The t r a n s f e r c y l i n d e r a c c o r d i n g t o c l a i m 8 , W h e r e i n t h ee l e c t r i c a l l y a c t u a te d l o c k i n g mechanism i n c l u d e s a l i n k e n ga g a b l e W i t h t h e d e v i c e a n d s e l e c t i v e l y a c t u a t e d by s o l e n o i d .

1 0 . A a n d i n g g e a r s y s t e m f o r a n a i r c r a f t , t h e l a n d i n g g e a rs y s t e m c o m p r i s i n g :a shock s t r u t having a s t r u t c y l i n d e r and a s t r u t p i s t o n

a r r a n g e d c o a x i a l l y , t h e p i s t o n m o v a b l e W i t h i n t h e c y l i nd e r t o move t h e shock s t r u t betWeen an extended l e n g t hand a s h r u n k l e n g t h , a v a r i a b l e l e n g t h s t r u t chamberl o c a t e d b e t W e e n t h e s t r u t c y l i n d e r a n d t h e s t r u t p i s t o n ,W h e r e i n t h e l e n g t h o f h e s t r u t chamber s p r o p o r t i o n a l toa l e n g t h o f t h e s h o c k s t r u t ;

a r e t r a c t a c t u a t o r h a v i n g a ? r s t p o r t i o n c o u p l e d t o t h e shocks t r u t a n d a n o t h e r p o r t i o n c o u p l e d o t h e i r c r a f t , W h e r e i na c t u a t i o n o f t h e r e t r a c t a c t u a t o r s e l e c t i v e l y p o s i t i o n s t h el a n d i n g g e a r i n t o one of ? i g h t con?guration o r a l a n di n g c o n ? g u r a t i o n ;

a t r a n s f e r d e v i c e con?gured t o t r a n s f e r h y d r a u l i c ? u i d t ot h e s t r u t s h r i n k chamber i n d e p e n d e n t o f t h e r e t r a c ta c t u a t o r , t h e t r a n s f e r d e v i c e h a v i n g a t r a n s f e r p i s t o nl o c a t e d i n a t r a n s f e r c y l i n d e r , t h e p i s t o n c o u p l e d to an o n - h y d r a u l i c a l l y a c tu a t e d d e v i c e c o u p l e d o th e i s t o n ,t h e d e v i c e o p e r a b l e t o move t h e p i s t o n betWeen a ? r s tp o s i t i o n a n d a s e c o n d p o s i t i o n W i t h i n t h e t r a n s f e r c y l i nd e r ; a n d

a motor p e r a b l y coupled o t h e d e v i c e t o move h e t r a n s f e rp i s t o n a n d p u s h h y d r a u l i c ? u i d o t h e s t r u t s h r i n k chamb e r , W h e r e i n t h e motor i s e n e r g i Z a b l e by a n e l e c t r i cs y s t e m o f t h e a i r c r a f t .

20

25

3 0

1 21 1 . T h e l a n d i n g g e a r s y s t e m a c c o r d i n g t o c l a i m 1 0 ,

Wherein h e h y d r a u l i c ?uid s l o c a t e d o n a s i d e o f t h e t r a n s f e rp i s t o n o p p o s i t e t h e d e v i c e .1 2 . T h e l a n d i n g g e a r s y s t e m a c c o r d i n g t o c l a i m 1 0 ,W h e r e i n t h e t r a n s f e r p i s t o n i s i n t e g r a l l y f o r m e d W i t h t h ed e v i c e .

1 3 . T h e l a n d i n g g e a r s y s t e m a c c o r d i n g t o c l a i m 1 0 ,Wherein t h e t r a n s f e r d e v i c e i n c l u d e s a b a l l screW engagedWith a b a l l n u t .1 4 . The l a n d i n g g e a r s y s t e m a c c o r d i n g t o c l a i m 1 3 , f u r t h e rc o m p r i s i n g a g e a r box e n g a g e d by t h e m o t o r a n d c o u p l e d t ot h e b a l l n u t .1 5 . The l a n d i n g g e a r s y s t e m a c c o r d i n g t o c l a i m 1 0 , f u r t h e rc o m p r i s i n g a l o c k i n g mechanism a c t u a t a b l e b y t h e p i s t o n t ol o c k t h e p i s t o n i n a d e s i r e d p o s i t i o n .1 6 . T h e l a n d i n g g e a r s y s t e m a c c o r d i n g t o c l a i m 1 5 ,Wherein t h e l o c k i n g mechanism i n c l u d e s a b l o c k v a l v e and as e n s o r p o s i t i o n e d o n an upper o r t i o n o f h e t r a n s f e r c y l i n d e r .1 7 . The l a n d i n g g e a r s y s t e m a c c o r d i n g t o c l a i m 1 0 , f u r t h e rc o m p r i s i n g a n e l e c t r i c a l l y a c t u a t e d l o c k i n g mechanism p e ra b l e t o l o c k t h e t r a n s f e r d e v i c e i n a d e s i r e d p o s i t i o n .

1 8 . T h e l a n d i n g g e a r s y s t e m a c c o r d i n g t o c l a i m 1 7 ,W h e r e i n t h e l e c t r i c a l l y a c t u a t e d l o c k i n g mechanism n c l u d e sa l i n k e n g a g a b l e W i t h t h e t r a n s f e r d e v i c e and s e l e c t i v e l y a c t ua t e d by a s o l e n o i d .1 9 . T h e l a n d i n g g e a r s y s t e m a c c o r d i n g t o c l a i m 1 0 ,Wherein t h e motor s an e l e c t r i c m o t o r .

2 0 . The l a n d i n g g e a r s y s t e m a c c o r d i n g t o c l a i m 1 0 , f u r t h e rc o m p r i s i n g a d r a g b r a c e c o u p l e d t o t h e s h o c k s t r u t and o t h ea i r c r a f t .