Licensable Technologies : Physics & Chemistry : Environmental/Waste Management

Drift Stabilizer for Reciprocating Free-piston Devices

Abstract
University of California scientists have developed a novel and useful method for stabilizing piston drift in reciprocating free-piston devices. These devices, which incorporate at least one piston that seals the internal volume into two spaces, are useful because they operate fully sealed for long periods. To maintain a tight seal between spaces, however, these devices do not use lubricants and must rely on close clearance fit between the piston body and the cylinder. Flow or leakage past the piston, albeit a near-negligible fraction of the total piston volume is theoretically fully reversing, yet small variances in the shape of the clearance gap can lead to preferential flow in one direction over the other. This causes accumulation of fluid on one side of the piston, resulting in drift of the center position of the piston. The current invention is a passive method to prevent this accumulation of fluid on one side of the piston, thereby maintaining stably centered, reliable free-piston operation.

Application(s)
· Power Generation to Engine generators · Gas compressors · Closed-cycle cooling machines/ Refrigeration

IP Status: Available both Exclusively and Non Exclusively

Reference Number: 169

S Number: DOE reference no.(s): 94,784

Patents & Applications:
United States National Patent Number 6564552 Issued on 05/20/2003

Posted: 09-17-2004

Contact
John Russell
Technology Transfer Division
Los Alamos National Laboratory
P.O. Box 1663, MailStop C334
(505) 665-3941
jrussell@lanl.gov