A cooling device employing a thermodynamic cycle of the reverse stirling cycle type is provided. The device includes a compressor with a reciprocating piston driven by a rotary motor about an axis by means of a crankshaft. The device further comprises a monobloc support forming a cylinder in which the piston of the compressor moves. The crankshaft is supported by a single bearing. The bearing is positioned without an intermediate component in a housing of the monobloc support.

A rotating machine is disclosed and includes a stator defining a circumference, a plurality of first magnet arrays, a rotor, and a first piston. The first magnet arrays are comprised of a plurality of discrete magnets arranged around the circumference of the stator in a first magnetic pattern. The rotor is rotatable about an axis of rotation and defines a main body. The main body defines a first passageway. The first piston includes a plurality of first magnetic elements and is actuated within the first passageway of the rotor. The plurality of discrete magnets are arranged in the first magnetic pattern and are positioned to interact with the magnetic elements of the first piston to create a first magnetic force as the rotor rotates about the axis of rotation. The first magnetic force represents a first amount of force required to actuate the first piston.

A heat regenerating material particle according to an embodiment includes a plurality of heat regenerating substance particles having a maximum volume specific heat value of 0.3 J/cm.sup.3.Math.K or more at a temperature of 20 K or lower, and a binder bonding the heat regenerating substance particles, the binder containing water insoluble resin. The heat regenerating material particle has a particle diameter of 500 m or less.

A cooler operating on the Stirling cycle, of the type including a compressor with a compression piston moving in a compression cylinder, a regenerator with a regeneration piston moving in a regeneration cylinder, a driving crankshaft including a crank pin that can rotate with respect to the compression cylinder and/or the regeneration cylinder, and a compression connecting rod, including a head mounted on the front pin and a foot articulated on the compression piston, the regeneration piston being connected to the crankshaft by a link element including at least three rigid adjacent sections connected by at least two spring-type connecting rods.

A cryocooler includes a second-stage cooling stage, a second cylinder which includes the second-stage cooling stage on a terminal of the second-stage cylinder, a second-stage displacer which includes a magnetic regenerator material and is accommodated in the second-stage cylinder so as to be able to reciprocate in the second-stage cylinder, and a tubular magnetic shield which is installed on the second-stage cooling stage and extends along the second-stage cylinder outside the second-stage cylinder. The magnetic shield is formed of a normal conductor and a product of an electrical conductivity in a temperature range of 10 K (Kelvin) or less and a thickness of the tubular magnetic shield is 60 MS (Mega-Siemens) to 1980 MS.

A pneumatic cryocooler using a pneumatic motor for use in cryogenically cooling superconductors, which pneumatic cryocooler is capable of operation in strong magnetic fields.

An expander unit of a cryogenic refrigerator device includes a moving assembly with a porous regenerative heat exchanger configured to move back and forth along a longitudinal axis. A magnetic spring assembly includes a stationary magnetic assembly fixed to the cold finger base that includes one or more magnetic rings fixedly arranged about a bore. A movable magnetic assembly includes one or more movable magnetic rings fixed to the moving assembly, An outer lateral dimension of each of the movable magnetic rings is less than an inner lateral dimension of the bore. The stationary magnetic assembly and the movable magnetic assembly are configured such that, when the moving assembly is displaced along the longitudinal axis from an equilibrium position, attractive and repulsive forces between the movable magnetic assembly and the stationary magnetic assembly yield a restoring force that is directed to restore the moving assembly to the equilibrium position.

A cooler operating according to the Stirling cycle, including a housing including a compression cylinder and a regeneration cylinder, a movable compression piston and a movable regeneration piston, that can move in translational motion in the compression cylinder and in the regeneration cylinder, a driving crankshaft, including a rotating crank pin, and two connecting rods coupled to the compression piston and the regeneration piston, the connecting rods being coupled to the rotating crank pin, a fluid flow duct for circulating fluid, connecting the compression cylinder and the regeneration cylinder, one end of the fluid flow duct being disposed on the regeneration piston, and the fluid flow duct including a deformable pipe that is deformed in accordance with the movement of the compression piston and/or of the regeneration piston.

A regenerator of a cryo-cooler uses helium both as a working gas and as a heat storage material. The regenerator includes cells whose exterior sides form flow channels through which the working gas flows. Each cell has connected first and second cavities enclosed by a heat-conductive cell wall. The cavities contain helium that is used to store heat. Each cells is shaped as a disk. The working gas flows both through the flow channels and around the regenerator so as to exchange heat with the helium in the cavities via the heat conducting cell wall. Each cell has a pressure-equalizing opening through the cell wall whose diameter is smaller than the thickness of the cell wall. The diameter of the pressure-equalizing opening is dimensioned to permit the pressure of the helium contained in the cell to change by a maximum of 20% during any working cycle of the cryo-cooler.

The present invention provides a regenerator material having a high specific heat in a temperature range of 10K or higher (in particular, a temperature range of 10 to 20K), as well as a regenerator and a refrigerator provided with the regenerator material. Specifically, the present invention provides a regenerator material represented by general formula (1): Er.sub.1xR.sub.xNi.sub.1+ (1), wherein x is 0<x<1, is 1<<1, and R is at least one member selected from Y and lanthanoids (excluding Er), as well as a regenerator and a refrigerator provided with the regenerator material.