Abstract: A spool valve for controlling the flow of a fluid into a reciprocating piston cylinder. A spool is slideably inserted into an outer casing, the spool valve having a first and a second non-waisted end portions and having a waisted middle portion. The casing has an intake port and output port for fluids entering and exiting the casing. A first non-waisted end portion covers the intake port during a first valve-closed event as the spool slides in one direction within the casing. The waisted middle portion is sufficiently wide to uncover both the intake port and the output port during a valve-open event as the spool slides in one direction within the casing. A second non-waisted end portion covers the output port during a second valve-closed event as the spool slides in the same one direction within the casing.

Abstract: There is provided a cryocooler including a cylinder, a displacer disposed inside the cylinder and driven to reciprocate by a gas pressure, a collar rigidly connected to the displacer to reciprocate together with the displacer, a collar chamber divided into an upper section and a lower section by the collar, a second seal portion provided between the displacer and the cylinder to seal the lower section, a lower bumper provided in the lower section to mitigate interference between the displacer and the cylinder when the displacer is located at a bottom dead center, and a communication passage formed in the collar or in the collar chamber to ensure communication between the upper section and the lower section when the displacer is located at a bottom dead center.

Abstract: Containers (100) for cryopreserved biological samples (102) may include an insulated housing including a cavity (108) for containing at least one cryopreserved biological sample; and a sealed reservoir (106) at least partly surrounding the cavity, the sealed reservoir including liquified gas (120) such as liquified air, the gas being kept largely liquified by a heat transfer engine (112) such as a Stirling cryocooler. A valve (114) may be provided to function as both a pressure relief valve and an inlet valve. The inlet valve may be coupled to a sensor (122) for sensing a volume of liquified gas within the sealed reservoir. The container may further include a heat exchanger (116) coupled to the heat engine and extending into the sealed reservoir.

Abstract: A heat station for a GM or Stirling cycle expander provides a versatile, efficient, and cost effective means of transferring heat from a remote load at cryogenic temperatures that is cooled by a circulating cryogen to the gas in a GM or Stirling cycle expander as the gas flows between a regenerator and a displaced volume. The heat exchanger includes a shell that has external and internal fins that are thermally connected, are aligned parallel to the axis of the shell, and are enclosed in a housing having a single port on the bottom of the housing.

Abstract: A Gifford-McMahon (GM) type double-inlet pulse tube system providing cooling at cryogenic temperatures is provided. The system has a co-axial double-inlet valve that includes a base having an adjustable port, a fixed needle partially engaged in one end of the adjustable port, an adjustable needle partially engaged in another end of said adjustable port, and a body for housing the base, the fixed needle and the adjustable needle. The base is configured to be adjustable along an axial direction. The adjustable needle is arranged co-axially with the fixed needle. The adjustable port and the adjustable needle are configured to control an alternating current (AC) flow and a direct current (DC) flow between the stem port and the end port and to produce the DC flow in either direction between the stem port and the end port.

Abstract: A device for isolating vibrations includes an ion trap, a cryocooler, a primary chamber, a secondary chamber, a vacuum ion pump, a heat exchanger, a sample chamber, a support part, a connector, a heat conduction part, a first platform, a second platform, and a flexible connecting part. The primary chamber, the secondary chamber, and the vacuum ion pump are fixedly disposed on the first platform. The connector is a hollow structure disposed between the primary chamber and the secondary chamber. The primary chamber communicates with the secondary chamber via the hollow structure thereby forming an airtight chamber. The vacuum ion pump is connected to the primary chamber via a five-way flange. The support part is fixed on the second platform. The cryocooler is fixed on the support part. The cryocooler includes a cold head and a machine head. The cold head is suspended in the primary chamber.

Abstract: A cool air supplying apparatus includes a swash plate shaft connected to a motor and extending in a predetermined axial direction; a compression swash plate obliquely coupled to the swash plate shaft; a compression piston configured to reciprocate in the axial direction by the rotation of the compression swash plate; a compression cylinder in which a working fluid is compressed by the compression piston, an expansion swash plate obliquely coupled to the swash plate shaft; an expansion piston configured to reciprocate in the axial direction by the rotation of the expansion swash plate; and an expansion cylinder arranged with the compression cylinder in the axial direction and configured to expand a working fluid compressed by the compression cylinder; and the compression swash plate and the expansion swash plate are installed in the swash plate shaft with a predetermined phase difference.

Abstract: A closed cycle regenerative heat engine has a housing defining a chamber. A displacer is housed in the chamber. A power piston is housed in the chamber. The displacer is resiliently deformable from a rest condition in response to displace the working fluid in the chamber. The displacer may be a multi-start volute spring. The displacer may be provided with a heat storage reservoir to store heat received from a working fluid as the working fluid is displaced from a heating location in the chamber to a cooling location in the chamber and reject heat to the working fluid when the working fluid is displaced from the cooling location to the heating location. The resiliently deformable displacer may comprise two components with an air space defined between the two components.

Abstract: A reduction in a permeability of refrigerant gas is suppressed while increasing a filling factor of regenerator material particles with respect to a stage of a cold head. A cold head includes a stage including regenerator material particle groups, and a metal mesh material partitioning the regenerator material particle groups. The metal mesh material has quadrangular mesh holes each having a length of a long side of 1/10 or more and ½ or less of each of average particle sizes of the regenerator material particle groups.

Abstract: The present invention discloses a speaker device. The speaker device comprises a speaker box, a heat source, and a heat conducting member; the speaker box comprises a housing, a speaker, a sound-guiding channel, and a heat conducting plate; the speaker includes a diaphragm, the first receiving space is divided into a front sounding chamber and a back chamber, and the sound-guiding channel communicates the front sounding chamber with the outside and forms a front chamber together with the front sounding chamber; the housing having an opening penetrating therethrough, the opening communicates with the front chamber, and the heat conducting plate covers on the opening, an adjusting hole penetrates through the housing and communicates with the back chamber; an valve covers on the adjusting hole and a controller for outputting a control signal to control the valve to open or to close.

Abstract: An apparatus, which may be operated as a heat engine and/or a heat pump, includes moveable separators at a cold side and/or moveable separators at a hot side. Each separator divides a volume into two smaller volumes. Working fluid may be sequentially filled and emptied from volumes between the separators. The separators may move to maintain uniform pressure in the volumes. Hot-side separators may allow for near adiabatic compression/expansion of working fluid. Cold-side separators may allow for near adiabatic expansion/compression of working fluid. Two displacers are positioned between the cold-side separators and the hot-side separators. The displacers are independently actuatable to force working fluid into and out of the volumes between separators and into and out of a variable intermediate volume between the displacers. Heat exchangers, including a warming heat exchanger, are provided to heat, cool, and warm working fluid as it flows between separated volumes and the intermediate volume.

Abstract: Refrigeration device intended to extract heat from at least one member by heat exchange with a working fluid circulating in the working circuit comprising in series: a fluid compression mechanism a fluid cooling mechanism, preferably isobaric or substantially isobaric, a fluid expansion mechanism, and a fluid heating mechanism, in which device the compression mechanism is of the centrifugal compression type and consists of two compression stages arranged in series in the circuit, the device comprising two respective electric drive motors driving the two compression stages, the expansion mechanism consisting of a turbine coupled to the motor of one of the compression stages, the turbine of the expansion mechanism being coupled to the drive motor of the first compression stage.

Abstract: A linear compressor includes a cylinder, a piston, a linear motor configured to drive the piston, a current detection unit configured to sense a current in the linear motor, a relay configured to change an operation mode of the linear motor, and a control unit configured to set at least one parameter for determining a stroke of the piston according to the operation mode. The control unit is configured to: determine a first magnitude of a first current in the linear motor based on a state of the relay being in a first state, determine a second magnitude of a second current in the linear motor based on the relay being switched to a second state from the first state, compare the first magnitude to the second magnitude, and based on the comparison of the first magnitude to the second magnitude, determine whether the relay fails to operate.

Abstract: A thermal management system for an aircraft is provided that includes thermo-acoustic engines that remove and capture waste heat from the aircraft engines, heat pumps powered by the acoustic waves generated from the waste heat that remove and capture electrical component waste heat from electrical components in the aircraft, and hollow tubes disposed in the aircraft configured to propagate mechanical energy to locations throughout the aircraft and to transfer the electrical component waste heat back to the aircraft engines to reduce overall aircraft mass and improve propulsive efficiency.

Abstract: According to one embodiment, there is provided a refrigeration system including detectors, each of which detects a phase indicative of a displacement of a displacer of each of cryogenic refrigerators; a processor that calculates an operation frequency of a motor of each of the cryogenic refrigerators, which is a frequency that suppresses oscillations or noises generated by reciprocating motions of the displacer of each of the cryogenic refrigerators, based on a detection result obtained by each of the detectors; and drivers, each of which drives the motor of each of the cryogenic refrigerators based on a calculation result obtained by the processor.

Abstract: A system includes: a piping with a working gas encapsulated therein and a prime mover and load incorporated in the piping. The prime mover includes a prime mover-side heat accumulator and heat exchangers connected to opposite end portions of the heat accumulator. The load includes a load-side heat accumulator and heat exchangers connected to opposite end portions of the heat accumulator. The piping includes a looped piping portion having a looped shape and a branch piping portion branching from a branching point p in the looped piping portion, and the prime mover is incorporated in the branch piping portion and load is incorporated in the looped piping portion. A blocking film is inserted at a position in a vicinity of the branching point p. Consequently, a thermoacoustic temperature control system that enables enhancement in durability of a blocking film inserted in a part of a looped piping portion is provided.

Abstract: 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.

Abstract: A cryogenic refrigerator includes a pulse tube cryocooler including a pulse tube, and a pulse tube cryocooler rotating mechanism that rotatably supports the pulse tube cryocooler allowing it to be changed from a cooling posture to a heating posture. When the pulse tube cryocooler is in the cooling posture, an inclination angle formed between a vertical line and a center axis of the pulse tube is a first angle, and when the pulse tube cryocooler is in the heating posture, the inclination angle is a second angle. In a case where the inclination angle formed when a cold end of the pulse tube faces vertically downward is defined as zero degrees and the inclination angle formed when the cold end of the pulse tube faces vertically upward is defined as 180 degrees, the second angle is larger than the first angle.

Abstract: The invention relates to a device for examining an atmosphere, comprising an atmosphere analysis chamber and a cryocooler, which is thermally coupled to the atmosphere analysis chamber for cooling the atmosphere analysis chamber. The invention further relates to the use of the device for examining an atmosphere, in particular the composition of an atmosphere.

Abstract: Provided is a method of disassembling a cold head provided with a displacer that extends in an axial direction, a cylinder that accommodates the displacer, and a displacer drive unit that is fastened to the cylinder and is connected to the displacer such that the displacer is driven in the axial direction, the method including mounting a lifting-up jig onto the displacer drive unit, unfastening the displacer drive unit and the cylinder from each other, and operating the lifting-up jig such that the displacer drive unit is lifted up from the cylinder together with the displacer.

Abstract: Methods/structures of joining package structures are described. Those methods/structures may include a first side of a die disposed on a first side of a substrate, and a cooling structure on a second side of the die, wherein the cooling structure comprises a first section attached to the substrate, and a second section disposed on a second side of the die, wherein the first and second sections are separated by an opening in the cooling structure. The opening surrounds a portion of the second section, and at least one flexure beam structure connects the first and second sections.

Abstract: A refrigeration device includes: a refrigerator; a heat pipe that includes a condensation unit connected to the refrigerator and adapted to condense a refrigerant, includes an evaporation unit connected to a storage chamber and adapted to evaporate the refrigerant, and includes a piping for circulating the refrigerant between the condensation unit and the evaporation unit; a heat pipe temperature sensor that detects a temperature of the heat pipe; and a control unit that controls driving of the refrigerator based on a result of detection by the heat pipe temperature sensor. The control unit controls the refrigerator so that the temperature of the heat pipe does not fall below a standard boiling temperature of the refrigerant.

Abstract: There is provided a mounting structure for mounting a cryocooler cold head on a vacuum vessel. The cold head includes a cold head-side cooling stage and a cold head-side flange. The mounting structure includes a cold head accommodation sleeve installed in the vacuum vessel and including a sleeve-side cooling stage which comes into thermal contact with the cold head-side cooling stage by coming into physical contact with the cold head-side cooling stage, and a sleeve-side flange to be coupled to the cold head-side flange, an inter-flange distance adjustment mechanism configured to adjust a distance between the sleeve-side flange and the cold head-side flange so that the cold head-side cooling stage and the sleeve-side cooling stage are physically brought into contact with each other or brought into a contactless state therebetween, and a flange fastening mechanism configured to fasten the cold head-side flange to the sleeve-side flange.

Abstract: A hybrid expander for producing refrigeration at a cryogenic temperature includes a Brayton expander producing refrigeration at a first temperature; a GM expander producing refrigeration at a second temperature, the first temperature being colder than the second temperature, the second temperature being 200K or less. A high pressure line receives a gas from a compressor at a first pressure and supplies it at the first pressure to the Brayton expander and the GM expander simultaneously. A low pressure line returns the gas to the compressor at a second pressure from the Brayton expander and the GM expander, the first pressure being greater than the second pressure. The Brayton expander piston is attached to the cold end of the GM expander displacer and the Brayton expander piston and the GM expander displacer reciprocating together.

Abstract: A split Stirling cryogenic refrigerator device may include a resonant pneumatic expander comprising a resonant displacer assembly supported by a spring and configured to slide back and forth along a longitudinal axis within a housing of the resonant pneumatic expander, the resonant displacer assembly comprising a tubular displacer containing a regenerator and coupled to a sealing piston, and a driving piston coupled to the sealing piston by an elongated radially compliant and axially rigid connecting member.

Abstract: 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/cm3·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.

Abstract: A Gifford-McMahon cryogenic refrigerator comprises a reciprocating displacer within a refrigeration volume. The displacer is pneumatically driven by a drive piston within a pneumatic drive volume. Pressure in the pneumatic drive volume is controlled by valving that causes the drive piston to follow a programmed displacement profile through stroke of the drive piston. The drive valving may include a proportional valve that provides continuously variable supply and exhaust of drive fluid. In a proportionally controlled feedback system, the valve into the drive volume is controlled to minimize error between a displacement signal and a programmed displacement profile. Valving to the warm end of the refrigeration volume may also be proportional. A passive force generator such as a mechanical spring or magnets may apply force to the piston in opposition to the driving force applied by the drive fluid.

Abstract: A method and a device for controlling a fan speed provided and may be applied to a server. According to an example of the method, a target DTS temperature curve corresponding to a current ambient temperature of the server is determined, and then, a DTS temperature corresponding to a current load of a power consumption component in the server is determined according to the target DTS temperature curve, and a speed of a fan associated with the power consumption component is adjusted according to the DTS temperature and a current temperature of the power consumption. The power consumption of the power consumption component and the power consumption of the fan are effectively balances by dynamically controlling the fan speed under different loads and at different ambient temperatures, thereby minimizing the power consumption of the server.

Abstract: A cryocooler includes a cold head, a valve unit which includes a rotary valve configured to periodically switch a pressure of a working gas in the cold head between a first high pressure and a second high pressure lower than the first high pressure and a valve motor configured to rotate the rotary valve, the valve unit having a rotation angle range in which the rotary valve seals the working gas having the second high pressure in the cold head, a cryocooler control unit configured to control the valve motor, a cryocooler stop instruction unit configured to output a cryocooler stop instruction signal to the cryocooler control unit, and a valve stop timing control unit configured to control the valve motor to stop the rotary valve in the rotation angle range, according to the cryocooler stop instruction signal.

Abstract: A system for vibration control of a cryocooler that cools an imager. The system includes a vibration sensor that is physically affixed to the cryocooler. The vibration sensor senses a physical vibration of the cryocooler and to generates a vibration signal therefrom. The system also includes cryocooler drive electronics operatively coupled to the vibration sensor and the cryocooler. The cryocooler drive electronics output a drive waveform that drives the cryocooler so as to reduce the vibration impact of the cryocooler. The harmonic content of the cryocooler drive waveform is controlled by the cryocooler drive electronics based on the vibration signal.

Abstract: The current document is directed to various types of oscillating resonant modules (“ORMs”), including linear-resonant vibration modules, that can be incorporated in a wide variety of appliances, devices, and systems to provide vibrational forces. The vibrational forces are produced by back-and-forth oscillation of a weight or member along a path, generally a segment of a space curve. A controller controls each of one or more ORMs to produce driving oscillations according to a control curve or control pattern for the ORM that specifies the frequency of the driving oscillations with respect to time. The driving oscillations, in turn, elicit a desired vibration response in the device, appliance, or system in which the one or more ORMs are included. The desired vibration response is achieved by selecting and scaling control patterns in view of known resonance frequencies of the device, appliance, or system.

Abstract: A cryocooler includes an expansion chamber, a cooling stage thermally coupled to the expansion chamber, the cooling stage including a first heat transfer block provided with a surface exposed to the expansion chamber and a first heat exchange surface disposed outside the expansion chamber and a second heat transfer block provided with a second heat exchange surface facing the first heat exchange surface, a refrigerant supply port installed in the cooling stage outside the expansion chamber, a refrigerant discharge port installed in the cooling stage outside the expansion chamber, and a refrigerant path fluidically separated from the expansion chamber, the refrigerant path being formed between the first heat transfer block and the second heat transfer block such that a refrigerant flows from the refrigerant supply port to the refrigerant discharge port along the first heat exchange surface and the second heat exchange surface.

Abstract: An apparatus includes a heat exchanger configured to transfer heat to a fluid and to absorb heat from the fluid as the fluid flows between a warm end and a cold end of a cryocooler. The heat exchanger includes at least one section having a substrate of at least one allotropic form of carbon and a layer of nanoparticles on or over the substrate. The heat exchanger could include multiple sections, and each section could include one of multiple substrates and one of multiple layers of nanoparticles. The heat exchanger can further include pores through the multiple sections of the heat exchanger, where the pores are configured to allow the fluid to flow through the heat exchanger and to contact the substrates and the layers of nanoparticles. The nanoparticles could include at least one lanthanide element or alloy, and the substrate could include carbon nanotubes or graphene.

Abstract: Various embodiments of space launch vehicle systems and associated methods of manufacture and use are disclosed herein. In some embodiments, the systems include a reusable, horizontal takeoff/horizontal landing (HTHL), ground-assisted single-stage-to-orbit (SSTO) spaceplane that is capable of providing frequent deliveries of people and/or cargo to Low Earth Orbit (LEO). In some embodiments, the spaceplane can takeoff with the aid of a rocket-powered sled that, in addition to providing additional thrust for takeoff, can also provide propellant for the spaceplane engines during the takeoff run so that the spaceplane launches with full propellant tanks.

Abstract: A cooling system, an apparatus for producing hyperpolarized samples, where the apparatus includes the cooling system, and a method for assembling and using the cooling system are disclosed. The cooling system includes a cryogenic chamber, a cooling plate, a sample sleeve, a thermal switch, and an interposer. Also, the cryogenic chamber includes a cryogenic fluid and the cooling plate is disposed in the cryogenic chamber, in contact with the cryogenic fluid. Further, the sample sleeve is configured to receive a sample. The sample sleeve is at least partially inserted in the cryogenic chamber. The thermal switch is disposed between the cooling plate and the sample sleeve. Moreover, the interposer is disposed between at least one of (i) the thermal switch and the cooling plate and (ii) the thermal switch and the sample sleeve. The interposer includes a gallium indium tin alloy.

Abstract: A rotary valve unit includes a rotary valve and a reversible motor. The rotary valve operates according to a cooling valve timing for cooling a pulse tube cryocooler when the reversible motor rotates in a forward direction and is operated according to a heating valve timing for heating the pulse tube cryocooler when the reversible motor rotates in a backward direction. The cooling valve timing is designed to generate a working gas pressure oscillation in a pulse tube and apply a first phase delay to a working gas displacement oscillation in the pulse tube with respect to the working gas pressure oscillation. The heating valve timing is designed to generate the working gas pressure oscillation in the pulse tube and apply a second different phase delay to the working gas displacement oscillation in the pulse tube with respect to the working gas pressure oscillation.

Abstract: The present invention relates to a cooling device (8) comprising: —a housing (22); —a crank (28) rotationally movable relative to the housing (22); —a piston (16); —a coupling component (34) rotationally mounted on the crank (28), the coupling component (34) having a first edge (54) facing the piston (16) and a second edge (56) opposite the first edge (54); —a deformable element (64) integrated in the coupling component (34) and integrated in the piston (16), the deformable element (64) being configured to translationally move the piston (16) relative to the housing while deforming, when the crank (28) is rotated relative to the housing (22), the deformable element (64) being integrated in the second edge (56) of the coupling component (34).

Abstract: The hybrid power generator is an emergency electric power generator. The hybrid power generator is configured to generate AC electrical power that is suitable for use in circumstances where the national electric grid has failed. The hybrid power generator comprises a housing and a power reserve circuit. The housing contains the power reserve circuit. The power reserve circuit: a) generates electrical energy using a fuel source; b) generates electrical energy using a photoelectric cell; c) stores the generated electrical energy as chemical potential energy; and, d) distributes the generated and stored electrical energy for use as AC electrical energy.

Abstract: An apparatus for performing energy transformation between thermal energy and acoustic energy is in a thermoacoustic transducer apparatus is disclosed. The acoustic energy is associated with a periodic flow of a working fluid within an acoustic power loop of the thermoacoustic transducer. The apparatus includes a common central plenum having a first fluid port for providing fluid communication with the acoustic power loop, and a plurality of discrete cylindrical thermal converters radially arranged about the plenum, each thermal converter including a regenerator. The apparatus also includes a second fluid port for providing fluid communication between the thermal converter and the acoustic power loop, and fluid flow passages in fluid communication with the plenum and extending through the regenerator to the second fluid port.

Abstract: A thermoacoustic cooling device includes a tube in which a working fluid is enclosed; a first stack that generates acoustic waves in the working fluid with use of a temperature gradient; a first high-temperature heat exchanger provided at a first side of the first stack to heat the first side of the first stack; a first low-temperature heat exchanger provided at a second side of the first stack; a second stack in which a temperature gradient is generated by the acoustic waves; a second high-temperature heat exchanger provided at a first side of the second stack, which has a high temperature; a second low-temperature heat exchanger provided at a second side of the second stack, which has a low temperature; and a heat transfer portion configured to connect the second low-temperature heat exchanger to the first low-temperature heat exchanger so as to transfer heat therebetween.

Abstract: A hybrid expander combines a Brayton engine first stage with one or more GM colder stages that uses the flow from the Brayton engine to provide refrigeration at one or more remote heat stations.

Abstract: A double acting alpha Stirling refrigerator includes a piston cylinder and a piston, the piston is provided in the piston cylinder. The piston is in a clearance fit with an inner wall of the piston cylinder. A closed cavity is formed inside the piston. A cross-shaped four-way pipe is provided in the cavity of the piston. A one-way air outlet valve and a one-way air inlet valve are further respectively provided on the four-way pipe in the cavity of the piston. An air outlet for connecting the cavity of the piston to the inner cavity of the piston cylinder is provided on the piston. A traction frame movable relative to the piston cylinder is provided outside the piston cylinder, and the movement of the piston is controlled by the movement of the traction frame.

Abstract: A heat station for a GM or Stirling cycle expander provides heat transfer from a remote load at cryogenic temperatures that is cooled by a circulating cryogen to the gas in a GM or Stirling cycle expander as the cryogen between a regenerator and a displaced volume. The heat exchanger includes a shell that has external and internal fins thermally connected to the shell that are aligned parallel to the axis of the shell and enclosed in a housing having an inlet port and an outlet port on the bottom of the housing.

Abstract: A cryocooler includes a displacer, a cylinder in which the displacer is accommodated, a Scotch yoke mechanism which drives the displacer, and a housing in which the Scotch yoke mechanism is accommodated. The Scotch yoke mechanism includes a crank, a yoke plate, a second drive shaft, and a first drive shaft. The housing may include a drive mechanism accommodation chamber in which the crank and the yoke plate are accommodated, a first assist chamber in which a distal end of the first drive shaft is accommodated, and a second assist chamber which is provided between the drive mechanism accommodation chamber and a gas chamber or between the drive mechanism accommodation chamber and the first assist chamber. The first assist chamber and the second assist chamber can be adjusted to a higher pressure than the pressure in the drive mechanism accommodation chamber.

Abstract: A four-process cycle is disclosed for a Vuilleumier heat pump that has mechatronically-controlled displacers. Vuilleumier heat pumps that use a crank to drive the displacers have been previously developed. However, mechatronic controls provides a greater degree of freedom to control the displacers. The four-process cycle provides a higher coefficient of performance than prior cycles in the crank-driven Vuilleumier heat pump and those previously disclosed for a mechatronically-driven Vuilleumier heat pump. The four-process cycle can be drawn out to provide a low demand condition by causing both displacers to remain stationary for a period of time. The four processes in which one of the displacers is commanded to move are separated by periods of inactivity in which both displacers remain stationary.

Abstract: A thermoacoustic refrigerator includes at least one pair of pulse combustion tubes (10), preferably Rijke tubes, each tube (10) having a pair of spaced-apart Stirling engines (12), coupled together but with no separating membrane therebetween.

Abstract: A rotary valve mechanism of a cryocooler includes a valve rotor and a valve stator. A rotor recessed portion is formed such that the rotor recessed portion fluidally communicates with a stator recessed portion at a first opening degree at a second phase of a valve rotation. The valve rotor includes a first rotor communication groove and/or a second rotor communication groove formed in the valve rotor such that the rotor recessed portion fluidally communicates with the stator recessed portion at an opening degree which is smaller than the first opening degree at a first phase preceding the second phase, and/or the valve stator includes a stator communication path formed in the valve stator such that the rotor recessed portion fluidally communicates with the stator recessed portion at an opening degree which is smaller than the first opening degree at the first phase preceding the second phase.

Abstract: A refrigerator includes a regenerator, a low-temperature end heat exchanger, a pulse tube, a high-temperature end heat exchanger, and a phase adjustment mechanism, connected in that order. A draft tube is provided inside the regenerator, paralleling the regenerator's axis, and the draft tube can extend into the low-temperature end heat exchanger.

Abstract: 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.

Abstract: A system for converting heat to kinetic energy is disclosed. The system may include a heat source, bimetallic bands and wheels that may support the bimetallic bands. The bimetallic bands may be heated by the heat source and may rotate the wheels. The rotation of the wheels may then be used to convert the kinetic energy to power.