Abstract: The invention relates to a device (21) for avoiding the memory effect in cryogenic pumps having a first cooling stage (23) and a second cooling stage (25) which adjoins the first cooling stage (23) in the axial direction. A cylindrical shield (31) has an opening (37) and a base (35), which base (35) is penetrated centrally by the two-stage cooling head (21) in such a way that the first cooling stage (23) is arranged outside the shield (31) and the second cooling stage (25) is arranged within the shield (31). An intermediate chamber (34) is formed between the shield (31) and the first cooling stage (23), and the base of the shield (31) is connected in a thermally conductive manner to the first cooling stage (23) by means of a thermal bridge (33). A cooling panel (43) which serves as pumping surface is connected to the second cooling stage (25) and is provided within the shield (31).

Abstract: The invention relates to a device (21) for avoiding the memory effect in cryogenic pumps having a first cooling stage (23) and a second cooling stage (25) which adjoins the first cooling stage (23) in the axial direction. A cylindrical shield (31) has an opening (37) and a base (35), which base (35) is penetrated centrally by the two-stage cooling head (21) in such a way that the first cooling stage (23) is arranged outside the shield (31) and the second cooling stage (25) is arranged within the shield (31). An intermediate chamber (34) is formed between the shield (31) and the first cooling stage (23), and the base of the shield (31) is connected in a thermally conductive manner to the first cooling stage (23) by means of a thermal bridge (33). A cooling panel (43) which serves as pumping surface is connected to the second cooling stage (25) and is provided within the shield (31).