Swivel support for gas bearing for position adjustment between ball and supporting cu

Pfaff, H.

English

NASA Technical Reports Server

ntrLY TO 
AlTN OF: G P  
MEMORANDUM 
TO: C 
FROM: 
NATIONAL AERONAUTICS AND SPACE ADMINISTRATION 
WASHINGTON, D.C. 20546 
April  5, 1971 
K, , I /Scient i f ic  & Technical Information Division 
Attn: M i s s  Winnie M. Morgan e 
~ ~ / ~ f f i c e  of Ass i s t an t  General 
Counsel f o r  Patent  Matters 
SUBJECT: Announcement of NASA-Owned 
U.S. Patents  i n  STAR 
I n  accordance with the  procedures contained i n  the  Code G P  
t o  Code US1 memorandum on t h i s  subject ,  dated June 8, 1970, 
t he  attached NASA-owned U.S. patent  is being forwarded f o r  
abs t rac t ing  and announcement i n  NASA STAR. 
The following information is provided : 
corporate Source 
Supplementary 
Corporate Source 
: ' ~ a r s h a l l  space F l igh t  Cen te r  I 
I NASA Patent  C a s e  No.: XMF-07808 
Gayle Parker 
Enclosure : 
Copy of Patent  
-- 
I 
(CATEGORY) 
I 
https://ntrs.nasa.gov/search.jsp?R=19710014336 2020-03-17T03:05:00+00:00Z
IN VEM TOR (S] 
HELMUTH PFAFF 
Aug. 26, 1M9 H. PFAFF 3,463,563 
SWIVEL SUPPORT FOR G A S  BEARINGS 
3,463,563 United States Patent O 6 c e  ,,,, .., , ,, 
1 2 
making very fine and precise adjustments between the 
3,463,563 relative position 'of the ball element and its sripporting 
SWIVEL SUPPORT FOR GAS BEAIRmGS cup has not heretofore been available. 
Helmutb PPfaB, Scot(sboro, A h ,  assagnor to the United 
States of America as represented by the Administrator SUMMARY OF THE PN'L'ENTIBN 
of the N a ~ o n a l  Aeronautics and Space Adminiskafion 5 
~h~ invention comprises a supparling cup having Filed Nov. 20, 1967, Ser. No. 684,178 
Int. CB. F16c 7/00, 9/00, 12/00 spherical supporting surface for receiving a ball and a sys- 
U.S. C1. 308-2 9 claims tem for providing a film of gas between the ball and the 
cup for minimizing friction between these bearing sur- 
]faces. The supporting cup is swiveled on a seat element 
ABSTRACT OF THE DISCLOSURE with the abutting surfaces of the seat and the cup being 
spherical and concentric with the surfaces between the ball 
A spherical supporting cup for the ball of a gas bearing and the cup. A shaft is rigidly conilected to the center 
with the cup being capable of being swiveled t o  change its of the cup and projects therebelow though an opening 
relative position to the ball while the bearing is under high in the center of the seat which opening i s  large: in dian-i- 
load. This adjustability has been found to enable a sub- eter than the diameter of the shaft. The end of the shafr 
stantial decrease in gas bearing "disturbance torques" opposite the cup is fitted with a spherical elenzent that is 
caused by a lack of optimum fit between the hall and the mounted in an ac'tuating mechanism that has the capability 
cup due to manufacturing tolerances. A shaft is rigidly of swivelling the shaft and thus the cup in any direction 
connected to the supporting CUP in the center thereof 20 up to a distance entirely adequate to establish an optimum 
and projects below the cup with the lower end of the shaft relationship between the ball and the cup. being provided with means for swivelling the shaft and Accordin~ly, it is a general object of the present in'ven- 
thus the gas bearing supporting cup. tion to provlde an improved suppoirting device for an air 
bearing. 
25 Another object of the invention is to provide a gas bear- The invention described herein was made by an em- ing having a bearing support for the ball of n gas bearing 
ployee of the united States Government and may be n~anu- that is capable of being adjusted to establish an optimum 
factured and used by or for the Government for govern- fit between the ball and the support. 
mental purposes without the payment of and royalties Another object of the invention is to provide a gas bear- 
thereon or therefor. 30 ing having a means for decreasing gas bearing "'disturbance 
BACKGROUND OF THE INVENTION torques" caused by manufacturing tolerances. 
These and other objects and advantages of the invention 
This invention relates generally to gas bearings and more will become apparent upon reference to the following 
particularly to a swivel support for gas bearings that Per- specification, attelldant claims a l ~ d  the draw~ilg. 
mits an adjustment of the relative position between the 
ball or a gas bearing and the supporting cup to decrease 35 BRIEF DESCRIPTION OF THE D R m l N G  
"disturbance torques" caused by necessary manufacturing FIGURE 1 is a cross sectional view of a gas bearing 
tolerances. embodying the swivel supporting cup of the present in- 
Bearings wherein a thin film of gas is employed to mini- vention; 
mize friction between bearing surfaces have become well FIGURE 2 is an elevational view, broken 
known in recent years and the advantages of such bearings away, taken along line 2-2 of FIGURE 1. 
over any other known type of bearing have been proven Referring to FIGURE 1, therein is shown a bail 11 srp- 
for  articular applications. Among the advantages afforded ported by a supporting cup 13 having a spher:cal support- 
by gas bearings is the major one of affording a marked ing surface 15 corresponding to the spherical surface of the 
reduction in friction between the bearing surfaces as corn- ball 11. The supporting cup 13 comprises two principal 
pared with liquid lubricated bearings. In addition to a long 4.5 elements, an outer housing elemellt 17 and an inner slip- 
life, other advantages include the elimination of contami- porting element 19 with the latter element supported in an 
nation problems caused by liquid lubricants as well as re- annular seat 21 formed in the upper portion of the hous- 
liable operation in extreme temperatures. ing element 17. In the center of the housing element 17 
while gas bearing components are necessarily manu- is a circular recess 23 within which fils a corresponding 
factured under very close tolerance requirements, in Cer- 50 portion 25 depending from and integral with the support- 
tain applications and uses of these bearings problems are ing element 19. The vertical dimension of the pmtion 25 
experienced with "disturbance torques" that are caused by is somewhat in excess of the depth of b e  recess 23 to pro- 
necessary manufacturing tolerances- These ''disturbance duce a space 29 between the elements 17 and 19, it. being 
torques" have been experienced in circumstances where a apparent that this space extends continuously around the 
relatively heavy load is being carried by a gas bearing 55 portion 25 to form a chamber which receives gas Ihrilugh 
and the so called "disturbance torques" apply an imbalance a passage 33 and a line 35 from a suitable source (not 
force on the bearing and consequently on the load carried shown). 
thereby due to the imperfect distribution of air between A series of gas passage orifices 37 formed in ;he support- 
the bearing and its supporting cup. Such imperfections in ing element 19 permit the passage of gas from the chamber 
the distribution of air is, as indicated ~ r e v i o u s l ~ ,  due to 60 29 to form a lubricating film of air between tIze ball 11 
the lack of an optimum fit between the spherical surface and the supporting cup 13. A plastic support ring 41 i s  
of the ball and the spherical supporting surface of the cup. mounted on lthe upper surface of the housing element 17 
Experimentations and tests pursuant to the elimination within a groove 43 and the support ring 41 has a spherical 
or diminishment of "disturbance torques" have revealed surface 45 that corresponds to the of the ball 11. 
that adjusting the relative position between the ball and 65 Sealing gaskets or rings 47 and 49 are in the 
its supporting cup under load conditions can establish an upper and lower portions, respectively, of Uhe supportir~g 
improved or optimum fit between the ball and its support- element 19. 
ing cup and thus produce a greatly improved distribution A central recess 55 is provided in the supporting eie- 
of the lubricating film of gas between the bearing surfaces. ment 19 having a reduced diameter portiol~ 55. Disposed 
Although gas bearings with various features and refine- 70 in the recessed portion 55 is a b d t  57 equipped witi? a ten- 
ments are known in the prior art, a satisfactory means for sion spring 59 which bolt extends through the lower pnr- 
3,463,563 
3 4 
tion of Bgic supporting element 19 and into a socket 61 in rail 165 and the crank screw is fitted with a handle 187. 
the lo;ver surface of the housing element 17 and also It  is evident that when the sliding block 141 is moved 
threads lcto a dowel portion 65 of a downwardly extend- lefl or light as indicated by the arrows (FIGURE 2 )  
Ing shaf~ 67. The bolt is covered at its upper end by a plug the shaft 67 will be moved wiih the block 141. When thc 
69 that fits into the large diameter portion of the recess sliding block 159 is moved left or right as indicated by the 
53, lhls plug being equipped with a sealing ring 71. A fur- ' arrows (FIGURE 1) the shaft 67 will move with the block 
ther connection between the supporting elements 17 and 159, and the block 141 and the rail 151 will also move 
19 i\ eflei:cd by a plurality of bolts 75 joined to the bot- with the block 159 since the rail 151 is connected by 
ton1 of the portion 25 of the element 19. The bolts 75 screws 157 to block 159. 
pdss through countc~sunk holes 77 in the bottom of the Thus by turning one or both of the crank screws 173 
housing eierncnt 17 so that each of the holes 77 has a and 181 the supporting cup 13 may be swiveled on the 
shoulder portion 79. Between the heads of the respective seat 87 of the pedestal 85 to any position within the zone 
bolts 75 and the shoulders 79 are compressed tension defined by the conical recess 91. The spherical bearing 
springs 81. These tcnsion springs permit the cup support- 135 rotates freely within the seat element 131 when the 
mg element 19 to raise slightly under the pressure of gas 15 shaft is being swiveled by turning either of the crank 
xnlroduccd into thc chamber 29. sclews 1173 or 181. A scale 189 may be provided on the 
The bot,om surface of the housing element 17 is spher- rail 165 and an indicator 191 provided on the sliding bar 
~ c a l  and 1s conne~tecl with the spherical surface of the ball 159 so that the optimum positian of the sliding bar can 
11. The houdng element 17 is seated on a hollow pedestal be read and recorded for any particular operation. A 
85 Paving s n  npl3er seat 87 with a spherical seating sur- 20 similar scale 193 and indicator 195 may be provided on 
face that corresponds to the bottom spherical sur- the rail 151 and sliding bar 141, respectively. 
face of the hous~cg element 17. In the center of the seat 87 It is apparent from the foregoing that the present in- 
is a hole 189 through which passes the shaft 67 with the vention provides a gas bearing support that may be pre- 
lioie 89 bcrng appreciably larger in diameter than the cisely adjusted under load conditions by changing the 
diameter of tlie shaft 67. Merging with the hole 89 is a 25 relative position between the supporting cup and the ball 
conrzal recess 91. supported thereby to diminish or decrease "disturbance 
The seat 87 is four-sided and is joined to a four-sided torques" caused by imperfect fits between the bearing and 
unll 95 ob tlic pedestal 85 by screws 97, the upper part of its support. 
the uliit 95 fiiiang into a peripheral groove 101 in the seat * Obviously, many modifications and variations of the 
87. The rrnil 95 is an integral four-sided unit comprising an 30 present invention are possible in the light of the above 
upper poitron 103 arid a lower portion 1105 united by struts teachings. it is, therefore, to be understood that within the 
109 siicii 1h31 two opposed sides of the unit 95 has open- scope of the attendant claims the invention may be prac- 
ings 111 and 11.3 therein and the remaining opposed sides ticed other than as specifically described. 
ha\ a p e l ~ i ~ g s  115 and $17 therein. The lower portion 105 I claim: 
of the ualt 95 fits m a gtoove 119 of a base plate 121 25 1. A gas bearing comprising: 
and is sec~ired to the base plate 121 by screws 123. (a)  a supporting cup having a spherical supporting sur- 
T132 ~ C : ~ P S  for swivelling the shaft 67 and thus the sup- face; 
pe:tlng cup 13 is installed in the central region of the (b) a ball having the spherical surface thereof overlying 
tinit 95 and coinprlses a shaft receiving block 125 that and contiguous with said spherical supporting sur- 
has a central hole 127 therethrough of changing diameter 40 face of said cup; 
to form a shoulder 129. Supported over the shoulder 129 (c)  means including a series of holes through said cup 
i s  a seat eiernziit 131 having a spherical cavity 133 therein for supplying a thin film of gas between said con- 
[hat receive5 a sphelical bearing 135 which is fixed on the tiguous spherical surface of said ball and said cup; 
shaft 67. The seat elenlent 131 is maintained in the opening (d) swivelling means connecting said cup to adjusting 
127 by a retdiner ling 139. means whereby said spherical supporting surface of 
The shafi receiving biock 125 is mounted by counter- 45 said cup may be adjusted relative to  the surface of 
silnh screws 143 on an actuating mechanism that includes said ball to produce an improved fit between said 
a sildlng hlocb I41 The sliding block 141 has a dovetail contiguous surfaces; and 
groove 147 ll~roughout its length that receives a dovetail ( e l  means securing said cup in an adjusted position 
projection 149 of a rail 151. The sliding block 141 also relative to said ball. 
has a centr-11 rib 153 that slides within a central groove 50 2. The invention as defined in claim 1 wherein said 
155 in the dovetail projection 149. The rail 151 extends swivelling means includes a shaft joined to and projecting 
the wldtil of the pedestal 55 and is joined by countersunk from said cup on the side thereof opposite said ball, an 
screws 157 to a second slidable block 159 that has a dove- actuating mechanism disposed in alignment with said shaft 
ta l i  groo\c 11611 therein (see FIGURE 2)  that runs in a said shaft being connected through a universal joint to  
dnre~t~on perpendicular to the dovetail groove 147 in the 5.5 said actuating mechanism. 
siiddble block 1411. The dovetail groove 161 receives a 3. The invention as defined in claim 2 including a ped- 
d~vetail  piogection 163 of a bottom rail 165 that extends estal having an interior cavity, said cup bearing on said 
.icioss the pedestal 55 and is connected to the base plate pedestal, said actuating mechanism being disposed in said 
121 by countersunk screws 167. The sliding block 159 cavity. 
Ilke;vise has a central rib 169 (FIGURE 2 )  that slides 60 4. The invention as defined in claim 2 wherein said 
witilia a central groove 171 in the dovetail projection connection between said shaft and said actuating mecha- 
163. nism includes a spherical bearing fixed to said shaft, a 
Tile slidable block 141 may be moved back and forth in bearing seat receiving said spherical bearing, means join- 
the d~rection oC the arrows (FIGURE 2 )  by a crank screw ing said bearing seat to said actuating mechanism. 
133 that i s  threaded into a threaded hole 175 in the cen- 6.5 5. The invention as defined in claim 2 wherein said 
tral rib 453 of the sliding bar 141. The crank screw is actuating mechanism includes a sliding block and a rail 
provided birth a handle 177 and is restricted to rotational said block being slidably mounted on said rail, means for 
movement in a jo~lrnal 179 secured as by screws or producing sliding motion of said block over said rail. 
welding to tbe end of the rail 151. 6.  The invention as defined in claim 5 wherein said 
The sliding bloclc 159 may be moved back and forth 'iO means for producing sliding motion includes a crank 
in the d~rectnoil ind~caled by the arrows (FIGURE 1) by screw, said crank screw threadedly engaging said block. 
a crank screw 1811 that is threaded into a threaded hole 7. The invention as defined in claim 2 wherein said 
183 in the central lib 169 of the sliding block 159. The actuating mechani~m includes a first sliding block and a 
crank scrcbv 181 is journalled for rotational movement first rail, said first sliding block being slidably mounted 
only In a joiiinal 185 mounted on the end of the bottom 75 on said first rail, a second rail mounted on and joined to 
3,463,563 
5 6 
said first sliding block, a second sliding block slidably substantially exceeding the diameter of said shaft where- 
mounted on said second rail, said first rail and said first by said shaft may swivel within said opening. 
sliding block being disposed at right angles to said second 
rail and said second block wherebv said first sliding block References Cited 
is slidable back and forth at rigit angles to thesliding 
movement of said second sliding block. 
8. The invention as defined in claim 1 including a 
pedestal supporting said cup; said pedestal comprising 
a seat element having a spherical supporting surface 
concentric with the spherical surface of said ball, 
said cup having a second spherical surface opposite 
said surface thereof contiguous with said ball, said 
second spherical surface of said cup fitted to and bearing 
on said supporting surface of said seat element. 
9. The invention as defined in claim 8 wherein said 
seat element has an opening through the center thereof, 
said swivelling means including a shaft joined to and 
projecting from said cup, said shaft extending through said 
opening in said seat element, the diameter of said opening 
UNITED STATES PATENTS 
1,098,023 5/1914 Deister. 
1,499,602 7/1924 Bibbins. 
2,397,300 3/1946 Tilton ---------------- 308-3 
3,13753 1 6/1964 Herrmann ------------ 308-9 
3,155,438 11/1964 Ruegg --------------- 308-72 
3,233,949 2/1966 Rieman. 
3,308,848 3/1967 Johnson ----------- 308-9 X 
MARTIN P. SCINVADRON, Primary Examiner 
L. L. JOHNSON, Assistant Examiner 
U.S. C1. X.R. 
308-9, 61 


Swivel support for gas bearings Patent

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