Miniature space pulse tube cryocoolers

Cryogenic coolers for use in space on small satellites require low power an d minimum weight. The need for exceptional reliability in a space cooler is made even more critical on small satellites since cooler redundancy is oft en not an option due to weight and power constraints. In this paper we repo rt on our space qualified pulse tube cooler designed specifically for use o n small satellites. The miniature pulse tube cooler is intended for greater than 10 year long-l ife space application and incorporates a non-weaning flexure bearing compre ssor vibrationally balanced by a motor-controlled balancer and a completely passive pulse tube cold head. The efficient cooler control electronics inc orporate temperature and vibration control systems as well as extensive tel emetry and engineering diagnostics. Cooler systems incorporating the mechan ical cooler and associated drive electronics have been flight qualified and launched in 1997 as focal plane coolers, Four additional flight coolers ha ve recently been delivered for use in cooling optics in an infrared telesco pe system. In this paper we report the performance and flight qualification of these mechanical coolers and flight electronics. (C) 1999 Elsevier Scie nce Ltd. All rights reserved.