NASA 1998 SBIR Phase I


PROPOSAL NUMBER: 98-1 22.04-3800

PROJECT TITLE: Gas Film Bearings for Reverse-Brayton Cryocoolers

TECHNICAL ABSTRACT (LIMIT 200 WORDS)

Self-acting gas bearings in miniature turbomachines provide exceptional reliability and eliminate vibration in space-borne reverse-Brayton cryocoolers. The ability to successfully manufacture these bearings with high precision has been a key factor in the success of our turbo-machine based cryocooler technology. Nevertheless, the methods that are presently used to produce these bearings are labor intensive, requiring a high degree of manual skill. The result is a costly, time consuming process to achieve the required level of precision in each bearing set. This project seeks to develop a novel, automatic method to manufacture the bore geometry of self-acting bearings. The method is suited to automated and repeatable manufacture so that the cost of the bearings would become a smaller fraction of the total cost of the cryocooler. The development of the tapered land bearing is the first step towards realizing a new bearing technology, suspended tapered land bearings, which will enable the turbomachine components of the coolers to be miniaturized. This technology is a critical element in extending the practical use of turbo reverse-Brayton cryocoolers to space applications in the 4 K - 10 K temperature range.

POTENTIAL COMMERCIAL APPLICATIONS

The proposed bearing fabrication technique will be used for the manufacture of cryocoolers used by NASA and the Department of Defense for spaceborne exploration and surveillance. The technique will significantly reduce the cost of cryocooler manufacture and will thereby promote their commercial application. These applications include communication satellites, cryopumping, magnetic resonance imaging systems, cryosurgery, cryocooled computer systems, small-scale superconducting energy storage, and ultra-high speed optoelectronic communication.

NAME AND ADDRESS OF PRINCIPAL INVESTIGATOR

John A. McCormick
Creare Incorporated
P.O. Box 71
Hanover , NH 03755

NAME AND ADDRESS OF OFFEROR

Creare Incorporated
P.O. Box 71, Etna Road
Hanover , NH 03755-0071