Abstract: A closed cycle Stirling cryogenic cooler, typically utilizing a noble gas (He or like) as a working fluid and containing a pneumatically driven expander interconnected with a low frequency pressure wave generator using a flexible transfer line or conduit, wherein the pressure wave generator includes a sealed gas discharge cavity containing the pressurized working fluid and a plurality of discharge electrodes which are electrically isolated, protrude through the walls of the cavity and are electrically connected to the high frequency pulse voltage supply, thus producing the glow discharge resulting in a cloud of cold plasma, making a so-called “plasmanized gas piston”.

Abstract: An apparatus for producing pressure oscillation of a fluid, incorporating hermetically sealed casing including a housing, a cover, a hermetic seal, a cylindrical flextensional transducer driven by piezoelectric or magnetostrictive driving member positioned in the inner cavity of the transducer and secured between two endplates, two springs providing for axial preloading and centering of the cylindrical flextensional transducer, two internal seals preventing fluid leakage between swept volume and other structure volumes; hermetic connectors for electrical connecting of the actuation member to energizing means, and fluid flow channel.

Abstract: A Stirling cooler made up of a first cylinder and a second cylinder. The first cylinder includes a driven piston for maintaining reciprocal gas displacement by compressing a gas in a closed cycle. The second cylinder is in fluid communication with the, first cylinder through a conduit which has a heat rejector in thermal contact with it, for rejecting heat from the second conduit. The second cylinder is made up of a displacer, an expansion chamber and a regenerator. The displacer normally oscillates within the second cylinder in response to gas pulses received through the conduit. The expansion chamber is at a first extremity of the second cylinder. The expansion chamber is cooled by the gas at the first extremity of the second cylinder. The piston is driven by means which drive the piston at a speed required for normal cooling generation resulting in displacer oscillation being less than 90 degrees out of phase with the piston.

Abstract: A cooling device for RF filters and a low noise amplifier is provided. The device supports and effects simultaneous cryogenic cooling of a plurality of radio frequency filters to a first temperature, and of a low-noise amplifier array, electically connected to the filters, to a second higher temperature. The device includes a two-stage refrigerating engine having spaced-apart first stage and second stage gas expansion chambers. The filters are mounted in thermal communication with the second stage gas expansion chamber and the low-noise amplifier array is mounted in thermal communication with the first stage gas expansion chamber.

Abstract: In order to control the passive motion of the pneumatically driven displacer in a cryogenic cooler system of the split cycle type, the refrigerant gas is forced to flow through a narrow passage within the pneumatic pillow in a manner that the gas during that passage is in viscous friction with the wall of the passage.