US 12,383,326 B2
Dual stage cryocooler
Satish Ramadhyani, Minneapolis, MN (US); Graig Kveen, Maple Grove, MN (US); and Harishankar Natesan, Minneapolis, MN (US)
Assigned to Biocompatibles UK Limited, Camberley (GB)
Filed by Biocompatibles UK Limited, Camberley (GB)
Filed on Aug. 21, 2023, as Appl. No. 18/236,312.
Application 18/236,312 is a division of application No. 16/994,110, filed on Aug. 14, 2020, granted, now 11,786,285.
Claims priority of provisional application 62/886,853, filed on Aug. 14, 2019.
Prior Publication US 2023/0389975 A1, Dec. 7, 2023
This patent is subject to a terminal disclaimer.
Int. Cl. A61B 18/02 (2006.01); A61B 18/00 (2006.01)
CPC A61B 18/02 (2013.01) [A61B 2018/00041 (2013.01); A61B 2018/00577 (2013.01); A61B 2018/0212 (2013.01)] 20 Claims
OG exemplary drawing
 
1. A cryoablation tool comprising:
a shaft having a proximal end and a distal end;
a primary supply conduit configured to supply a primary fluid from a high-pressure cryogenic gas source to a distal end of the shaft, the primary supply conduit comprising a first Joule-Thomson (J-T) orifice, configured to deliver the primary fluid to a first expansion chamber;
a primary return conduit configured to carry the primary fluid away from the first expansion chamber;
a secondary supply conduit configured to supply a secondary fluid to a second J-T orifice, the second J-T orifice configured to deliver the secondary fluid to a second expansion chamber; and
a secondary return conduit configured to carry the secondary fluid away from the second expansion chamber,
the primary supply conduit comprising a primary-secondary heat exchange region and a primary-primary heat exchange region, the primary-primary heat exchange region being down stream of the primary-secondary heat exchange region; and the secondary supply conduit comprising a secondary-secondary heat exchange region up stream of the second J-T orifice, and
the primary return conduit further configured to pass the primary fluid over the primary-primary heat exchange region, in counterflow to the supply direction; the secondary return conduit further configured to pass the secondary fluid sequentially over the primary-secondary heat exchange region and the secondary-secondary heat exchange region in counterflow to the supply direction.