A new thermo-mechanical structure design for space qualified close-cycle dilution refrigerator

New cryogenic space missions, such as post-Planck projects, will need longer observation times with detectors cooled down to 100 mK. A space CCDR (Closed-Cycle Dilution Refrigerator) version is being developed. A Demonstration Model of such CCDR, working in a laboratory environment, has already been developed. The development of an EM (Engineering Model) needs to work without gravity while sustaining the high level of vibrations during a mission launch thanks to a mechanical structure also limiting thermal exchanges between the various temperature stages. We present here the thermo-mechanical structure that has been optimized to maintain the multiple components of the CCDR. The expected performance from a thermo-mechanical model analysis is compared with preliminary thermal conductivity measurements.