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In February 2002, ASTRIUM selected AL/DTA for the delivery of the vial freezers for the ESA / CRYOSYSTEM project. The CRYOSYSTEM is a set of facilities for ultra-rapid cooling, preservation and storage of biological samples and protein crystals at -180°C on-board the ISS. While selecting the cooler for this program, AL/DTA recognised that THALES’ moving magnet flexure-bearing coolers offer the reliability required for space programs, for a price that is far below what is usual for space cryocoolers. Based on the cold finger of the existing LSF9320 cryocooler (5.6 W at 80 K for 150 W input), THALES has developed a cold finger with flexure-bearing support of the displacer. Combined with the moving magnet flexure-bearing compressor, this offers a very long lifetime and a very high reliability. The paper describes the development of the flexure-bearing supported displacer, which has an extra driving rod to increase its efficiency compared with conventional free displacer fingers. The efficiency optimisation and mass reduction has led to a cooler with a total mass (including heat-sinking and EMI shield) of 7.8 kg, with a cooling power of 6.6 W at 75 K for 100 W input. The results of the ongoing space qualification program will be discussed. © 2004 American Institute of Physics [ABSTRACT FROM AUTHOR]

Thales Cryogenics (NL) and Thales Cryogenie (F), formerly known as Signaal Usfa and Cryotechnologies, closely co-operate in the field of production and development of linear and rotary cryocoolers. Over the past years, Thales Cryogenics has developed a complete range of Stirling cryocoolers with flexure bearings. In this paper the main design features of the flexure bearing compressor are explained. With these flexure bearing cryocoolers, which are available in slip-on configuration as well as IDCA (Integrated Detector Cooler Assembly), up to 6W @80K cooling power can be obtained. Also a pulse tube cryocooler with a specified cooling power of 500 mW @80K has been developed. Two specific production machines have been developed and introduced in the production line. With this equipment Thales Cryogenics has been able to further improve the quality and reproducibility of its coolers. Up to now, several flexure bearing cryocoolers have been built and integrated in various new commercial and military applications requiring long life cryocoolers. Besides this, Thales Cryogenics is active in several space applications in co-operation with Air Liquide/DTA. [ABSTRACT FROM AUTHOR]

Developments on high frequency high heat lift pulse tubes are carried out at CEA/SBT. Based on a previous study on an in line configuration, two new pulse tube cold fingers have been manufactured: a coaxial configuration and a U-shape configuration. Measurements performed with the coaxial configuration have demonstrated cooling power in excess of 6 W at 80 K with 140 W of mechanical input power. The results obtained with these two configurations are presented. The impact of the rejection temperature has also been studied and is discussed. In parallel, a new compressor with pistons supported by flexure bearings has been designed and manufactured. This compressor has been coupled with the pulse tube. Tests performed with the new developed flexure-bearing compressors and a conventional compressor are presented and compared. The pulse tube cold finger associated with the new compressor leads to a reliable and low vibration cooler. © 2004 American Institute of Physics [ABSTRACT FROM AUTHOR]

An Engineering Model (EM) of a Miniature Pulse Tube Cooler (MPTC) has been designed and manufactured. The expected performance of the MPTC were 1240 mW heat lift at 80 K with 288 K ambient temperature and 40 Watts rms maximum input power to the compressor motors. The EM is a U shape configuration operated with an inertance tube. The design and optimisation of the compressor and the Pulse Tube cold finger are described. The thermal performance test results are presented and discussed as well. This work is performed within a Technological Research Project (TRP) funded by ESA (Contract 14896/00/NL/PA). © 2004 American Institute of Physics [ABSTRACT FROM AUTHOR]