Bearing has restrictions to reduce air leaks and is connected to external pumpout facility which removes exhausted air. Token amount of air which is lost to vacuum is easily removed by conventional vacuum pump

Perkins, G. S.

English

NASA Technical Reports Server

April 1975	 B75-10052 
NASA TECH BRIEF 
NASA Pasadena Office 
NASA Tech Briefs announce new technology derived from the U.S. space program. They are issued to encourage 
commercial application. Tech Briefs are available on a subscription basis from the National Technical Information 
Service, Springfield, Virginia 22151. Requests for individual copies or questions relating to the Tech Brief program may 
be directed to the Technology Utilization Office, NASA, Code KT, Washington, D.C. 20546. 
Gas Bearing Operates in Vacuum 
.
Typical gas bearings are not suited for operation in 
vacuum chambers. Air exhausted from these bearings 
disturbs the vacuum environment which makes it 
necessary to use large, expensive vacuum pumps. A 
better approach is to use a newly-developed gas 
bearing which operates in vacuum without seriously 
disturbing it. 
The new bearing has restrictions to reduce- air 
leaks. It is connected to an external pumpout facility 
which removes exhausted air. A token amount of air 
which is lost to vacuum is easily removed by a 
conventional vacuum pump. 
The entire assembly designed to 'test attitude 
control systems is shown in the illustration. Inthis 
design, a test object support platform is attached to a 
rotor member which has a spoollike configuration. 
The stator housing assembly generally is made up of a 
bottom base plate, which serves as a support, and a 
series of ring and plate members. These members are 
secured by the long bolts on the ends of the assembly 
Groove	 Rotor Member (Upper)
The upper portion of the rotor has a lower surface 
that includes a circular undercut and a groove which, 
together with matching portions of an upper ring 
member of the stator assembly, form annular 
passageways for gas flow. One bearing for the upper 
rotor member is the flat section extending between an 
undercut and a groove. The flat portion of this 
undersurface extending between the groove and the 
edge, together with the matching surface portion of 
the ring member below, constitutes the restrictive 
gap. The separation between these surfaces is 0.01 
mm (0.0004 in.). 
The rotor has a cylindrical portion which serves as a 
journal member. The lower rotor section supports the 
entire rotor assembly in the stator housing during 
operation. It is provided with a liftup force on the 
order of 893 N (about 200 lb). The upper surface of 
the lower rotor section is also provided with an 
undercut adjacent to the flat section. The flat section 
forms a second bearing surface for the rotor. The web 
of this section is pierced as indicated with a series of 
vertical openings which serve as exhaust passages. 
Restrictor 
rtion	 \ Bearing Po  Surface Circular Undercut
Support 
Platform	 Plug Resistors
Plate Members 
Gas	 Spacer 
Restriction 
Slot 
Circular	 \	 \Rotor Member 
F	 Bearing	 Vertical
	 Undercut	 Cylindrical	 (Lower) 
Bottom	 Surface Opening
	 Portion of 
Plate	 Rotor 
S	 Gas Bearing Configuration
(continued overleaf) 
This document was prepared under the sponsorship of the National 	 Government assumes any liability resulting frOm the use of the 
Aeronautics and Space Administration. Neither the United States 	 information contained in this document, or warrants that such use 
Government nor any person acting on behalf of the United States	 will be free from privately owned rights.
https://ntrs.nasa.gov/search.jsp?R=19750000052 2020-03-19T20:00:47+00:00Z
. 
The bottom plate supports the lower ring, which in 
turn supports an assembly made up of plate members 
that are bolted together, with a washer-like spacer 
member forming a narrow circular restriction slot 
between adjacent faces of the plate members. The 
dimension of this slot is 0.005 mm (0.0002 in.). The 
plate members include vertical bores into which plug 
resistors are inserted. The resistors provide special 
passageways to convey gas under pressure. 
Gas under pressure is fed from an external source 
through the plug resistors. The resulting internal 
pressures suspend the rotor to provide frictionless 
operation. Two outlet ducts are used to remove the 
gas, preventing it from contaminating the vacuum 
environment.
Note: 
Requests for further information may be directed 
to:
Technology Utilization Officer 
NASA Pasadena Office 
4800 Oak Grove Drive 
Pasadena, California 91103 
Reference: TSP75- 10052 
Patent status: 
NASA has decided not to apply for a patent. 
Source: Gerald S. Perkins of
Caltech/JPL
under contract to
NASA Pasadena Office
(NPO-13425)
S 
S 
Categories: 06 (Mechanics) 
B75-10052	 07 (Machinery)


Gas bearing operates in vacuum

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