Patent ID: 7370482

Claim:
A cryogenic trap comprising, in a hollow body ( 3 ) having a peripheral wall ( 3 a ), a contact surface ( 13 a ) disposed in contact with gases to be trapped, cold generator means ( 11 , 12 ) for cooling the contact surface ( 13 a ) to a temperature that is appropriate for condensing and solidifying the gases to be trapped, and heater means for periodically eliminating the layer of ice ( 22 ) which becomes deposited on the contact surface ( 13 a ) during trapping, the trap being characterized in that: the contact surface ( 13 a ) is a thermally-isolated element ( 13 ), itself having low thermal inertia; the contact surface ( 13 a ) is thermally connected to the cold generator means ( 11 , 12 ) via heat transmission means presenting: a first state with high conductance for gas trapping stages; and a second state with low conductance ( 23 ) for regeneration stages; the heater means ( 14 ) are continuously at a distance from the cold generator means ( 11 , 12 ) and are provided to heat the contact surface ( 13 a ) selectively during the regeneration stages; and isolation means (F 1 ) are provided for keeping the gases to be trapped away from the cold generator means ( 11 , 12 ).