Abstract: An aircraft comprising a heat exchanging pack comprising an energy recovering module with a hot and a cold side, the hot side thermally contacting the cold side, providing a heat exchange. The heat exchanging pack also comprises a secondary heat exchanger and a compressor coupled with a turbine. The hot side module inlet fluidly communicates with the bleed air duct, the cold side module inlet fluidly communicates with the ram air duct, the hot side module outlet fluidly communicates with the compressor inlet, the compressor outlet fluidly communicates with the hot side secondary inlet, the hot side secondary outlet fluidly communicates with the turbine inlet, and the cold side secondary inlet fluidly communicates with the ram air duct. The energy recovering module comprises a conversion apparatus, configured to generate energy out from the heat exchange taking place in the energy recovering module between the hot and cold sides.

Abstract: A cooling device comprises a cooling tube containing a working gas, a pressure oscillator connected to a first end of the cooling tube to generate a pressure oscillation and displacement of the working gas, and means for phase shifting the pressure oscillation relative to displacement of the working gas, connected to a second end of the cooling tube. The device further comprises a first sealed pressure transmission element to separate the working gas from a fluid contained in the phase shifting means. The fluid and the working gas are of different natures.

Abstract: A crank-piston mechanism for a reciprocating double-acting piston-type gas compressor that allows for infinitely variable compression ratios during operations. The mechanism includes a gear pin crankshaft, a forward piston-connecting rod, a rearward piston-connecting rod, a forward crosshead, a rearward tubular crosshead, and a tandem piston assembly. The forward piston-connecting rod and the rearward piston-connecting rod are each rotatably connected to the gear pin crankshaft about two parallel but offset axes. On the opposite end, the forward piston-connecting rod and the rearward piston-connecting rod are connected to the forward crosshead and the rearward tubular crosshead, respectively. Wherein, the forward crosshead is slidably mounted within the rearward tubular crosshead. The forward crosshead is connected to a forward piston from the tandem piston assembly and the rearward tubular crosshead is connected to a rearward piston from the tandem piston assembly.

Abstract: A disclosed cryogenic refrigerator includes a cylinder, a displacer reciprocally moving inside the cylinder, and an elastic unit which is provided in at least one of a pair of end regions respectively including a pair of end portions within a range of a reciprocal motion of the displacer, accumulates an elastic force when the displacer approaches the end portion, and releases the elastic force when the displacer departs from the end portion.

Abstract: The present invention relates to a heat engine having a housing. A generally triangular shaped rotor can drive an offset crank as it eccentrically rotates within the housing. Two inlets with valves and two exhausts are provided. The volume between each face of the rotor and the housing defines three expansion chambers. Six power cycles are provided (one by each expansion chamber times two inlets) per revolution of the rotor. Each valve controls the length of time that high pressure gas is allowed to enter each expansion chamber. The valves are controlled by a processor and close when enough pressure is supplied so that the pressures inside and outside the expansion chamber are equal when the chamber is fully expanded just prior to exhaust. Gates can provide a mechanical advantage to the rotor by reducing the amount of pressure applied to the back side of the fulcrum.

Abstract: A method for use in controlling a free piston Stirling machine having a cold end and a warm end and driven by a linear motor having an armature winding to which a drive voltage is applied. The method comprises (a) sensing internal mechanical collisions; (b) repeatedly sensing the temperature of the cold end, the temperature of the warm end and the drive voltage; (c) storing, as associated data, a value representing drive voltage, the temperature of the cold end and the temperature of the warm end at the time of sensed collisions; and (d) limiting the drive voltage to less than the drive voltage that was sensed at a collision and is stored in association with stored warm end and cold end temperatures that are proximate currently sensed warm end and cold end temperatures.

Abstract: In a case of performing a static pressure gas lubrication by a stirling engine provided with a pair of cylinders of a high-temperature-side cylinder 20 and a low-temperature-side cylinder 30, a stirling engine gas lubrication structure is provided with an introduction pipe 70A for introducing a working fluid existing within a low-temperature working space into at least an inside of an expansion piston 21 of the expansion piston 21 and a compression piston 31, the low-temperature working space being included in a working space where the working fluid circulates between the cylinders 20 and 30, a temperature of the working fluid in the low-temperature working space lower than that of the working fluid in a working space of a high-temperature side cylinder 22 in a driving state.

Abstract: The present invention provides a Stirling engine capable of effectively recovering heat from exhaust gas flowing through a flue, and connecting a heating portion 10 and a regeneration portion 5 with each other through an operation gas tube without providing a flow passage separating portion 110, and the heating portion 10 includes a heating portion head 10a and a heat-transfer tube group, the heating portion head 10a includes first through holes 30R and second through holes 30S, the first through holes 30R are formed closer to a center region of the heating portion head 10a as compared with the second through holes 30S, one ends of U-shaped tubes are mounted in the first through holes 30R and the other ends of them are mounted in the second through holes 30S, and parallel exhaust gas flow passages is formed between the U-shaped tubes.

Abstract: An opposed piston gamma type Stirling machine has its displacer driven by a linear electromagnetic transducer that is drivingly linked to the displacer and is located on the opposite side of the power piston's axis of reciprocation from the displacer preferably in the bounce space. The linear transducer is controlled by an electronic control as a function of sensed inputs of Stirling machine operating parameters. In addition to allowing improvements in stability and efficiency, such a Stirling machine operated as a cooler/heat pump can also be controlled so that its displacer can be driven at (1) a phase angle that pumps heat in one direction through the machine or (2) at another phase angle that pumps heat in the opposite direction through the machine and allows selectively switching between the heat pumping directions.

Abstract: An improved free piston Stirling machine having a gamma configuration. The displacer and each piston is reciprocatable within a cylinder having an unobstructed opening at its inner end into a common volume of the workspace. The common volume is defined by the intersection of inward projections of the displacer cylinder and the piston cylinders. The displacer and the pistons each have a range of reciprocation that extends into the common volume. A displacer drive rod is reciprocatable in a drive rod cylinder and both are positioned outside the common volume and on the opposite side of the common volume from the displacer. The displacer is connected to the displacer drive rod by a displacer connecting rod. Importantly, the displacer and pistons have complementary interfacing surface contours formed on their inner ends which substantially reduces the dead volume of this gamma configured machine.

Abstract: An external combustion engine comprising a drive shaft, a first cylinder kinematically connected to the drive shaft, a second cylinder kinematically connected to the drive shaft, and a thermodynamic circuit fluidly connected to both the cylinders, and having at least an expansion chamber and a compression chamber for a heat-carrying fluid, in order to determine the cyclic movement of the first cylinder and the second cylinder. The first cylinder is mounted on a first support frame and the second cylinder is mounted on a second support frame, distinct from and constrained in a mobile manner to the first support frame. Movement means are mechanically connected to the first support frame and/or the second support frame, in order to determine the desired relative movement of the first support frame and the second support frame and to vary the reciprocal kinematic connection phasing of the two cylinders with respect to the drive shaft.

Abstract: A heat engine includes: a high-temperature space portion and a low-temperature space portion, each of which has a working gas with a different temperature range from each other; a regenerator provided between both of the space portions; a first piston configured to cause volumetric changes of the working gases in the space portions and transmit motive energy on receipt of pressure changes of the working gases; and a second piston and a third piston configured to transfer the working gases between both of the space portions and move with a 180° phase difference from each other with respect to the regenerator. The second piston is slidably housed in a cylinder portion included in the first piston. Heat and motive energy are exchanged by using the volumetric changes in both of the space portions, as well as by using the transfer of the working gases.

Abstract: A free piston Stirling machine including a thermal buffer tube extending from the machine's expansion space and surrounded by its heat rejector and its regenerator, a displacer cylinder extending from the thermal buffer tube to the compression space and surrounded by the heat rejecting heat exchanger, and a displacer that reciprocates within an excursion limit that extends into the regenerator by no more than 20% of the length of the regenerator during normal operation and preferably within excursion limits that are substantially the length of the heat rejector.

Abstract: A heat machine having an external heat source and an external heat sink may be configured as a Stirling engine having a hot pair of cylinder-and-displacer combinations 15 and a cold pair of cylinder-and-displacer combinations 16 though advantageously two pairs of hot combinations 15 and two pairs of cold combinations 16 are provided, arranged mutually at right angles. Mechanisms 20 associated with the hot and cold displacers controls the movement thereof to be truly sinusoidal and are contained within casings 21. The pressure in the working fluid spaces remote from the mechanisms 20 and also the pressure in the casings 21 is monitored and compared, and then is controlled such that the casing pressure is slightly less than the minimum working fluid pressure in the working fluid spaces. The relative phase of the two mechanisms 20 associated respectively with the hot displacers and the cold displacers is adjustable (28,29,30,31; and FIG. 4).

Abstract: A thermal-cycle cryocooler, such as a Stirling-cycle cryocooler, has a single working volume that is utilized by both the compressor and the displacer. The compressor and the displacer have respective movable parts, one of which is surrounded by the other. One of the parts may be a piston, a portion of which moves within a central bore or opening in a cylinder that is the other movable part. The piston may be a component of the compressor and the cylinder may be a component of the displacer, or vice versa. The working volume is located in part in a bore of the cylinder, between the piston and a regenerator that is coupled to the cylinder. Movements of either the piston or the cylinder can directly (i.e. without the use of a gas transfer line or flow passage) cause compression or expansion of the working gas in the working volume.

Abstract: The power output of a free piston Stirling engine mounted in a free casing configuration is controlled by having a spring drivingly linking the displacer to the casing and controllably varying the amplitude of reciprocation of the casing. A variable casing reciprocation restraint is linked to the casing for applying a variable restraining force to the casing. The restraining force is increased for decreasing the displacer amplitude of reciprocation and thereby decreasing the power output from the Stirling engine and the restraining force is decreased for increasing the displacer amplitude of reciprocation and thereby increasing the power output from the Stirling engine.

Abstract: An ECU is used for a Stirling engine that is provided with a starter that drives an output shaft of the Stirling engine. The ECU includes a control portion that commences an engine-starting drive of the starter within a phase interval, during which the torque of the Stirling engine that varies according to phase of the output shaft is relatively small. The phase interval is an interval during which the torque of the Stirling engine is less than or equal to the torque obtained when the compression begins. The phase at which the driving of the starter is commenced is set to the phase at which the torque of the Stirling engine becomes smaller than the torque obtained when the compression begins.

Abstract: A method and apparatus that reduces the dead volume in a heat engine or heat pump, such as a duplex Stirling or Vuilleumier cycle device, by nesting the components of the displacer and regenerator such that nearly all working fluid is purged from the interstices of the regenerator elements and all other working fluid spaces that are not involved in doing useful work at each portion of the cycle. Particularly, a more scalable and efficient method and apparatus for providing solar air conditioning or refrigeration by means of a heated cylinder that alternately pressurizes and depressurizes a separate cooling cylinder by directly transferring thermally induced pressure changes to that cooling cylinder at optimized times in the cycle, under the control of a numerically controlled actuation system that can cycle at a much lower rate than mechanically coupled or harmonically phased systems.

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: A thermoelectric converter includes one or more thermoelectric converter modules. A thermoelectric converter module includes spatially delimited gas volumes interconnected by a regenerator in a gas-permeable manner. During operation of the thermoelectric converter, a first gas volume warmer than the ambient temperature or a fluid flow is heated, and a second gas volume is cooler than the first gas volume. A fluid flow is thermally coupled with the second gas volume to dissipate heat. A volume change element suited to change the size of one or more of the gas volumes can be moved or deformed by an electromagnetic component by creating a magnetic field such that the size of at least one of the gas volumes is changed.

Abstract: A compact cryocooler includes a gas compression piston (304) supported for reciprocal linear translation along a first longitudinal axis (308) and a gas displacing piston (362) supported for reciprocal linear translation along a second longitudinal axis (366). The first longitudinal axis (308) and second longitudinal axis (366) are substantially orthogonal. A rotary motor (302) rotates a rotor (324) and associated motor shaft (320) about a motor rotation axis (328) disposed substantially parallel with the second longitudinal axis (366). Motor shaft (320) first and second mounting features (336, 340) traverse first and second eccentric paths around the motor rotation axis. A first drive coupling couples the first mounting feature (336) with the gas compression piston (304) and delivers a reciprocal linear translation along the first longitudinal axis (308) thereto.

Abstract: A heat engine with external hot source in which the engine has at least one variable volume working chamber for a working gas, and a distribution mechanism that connects this chamber to a cold input from an energy receiving path during an outgoing transfer phase and to a hot output of the energy receiving path during an incoming transfer phase, the energy receiving path being intended to heat the working gas outside the chamber on contact with the external hot source, wherein the distribution mechanism is timed in such a way as to: maintain pressure in the energy receiving path; during stable operation, connect the working chamber with the cold input from the energy receiving path whilst the pressure in the chamber is lower than the pressure in the energy receiving path.

Abstract: A Stirling engine that implements a Stirling cycle is described. The Stirling engine may have a power piston and a main displacer coupled to a camshaft by means of a 90°-dwell positive return cam and yoke system. The Stirling engine achieves gaseous working fluid displacement using the main displacer and the co-displacer. The co-displacer alternately locks between the main displacer and the power piston, which enables the main displacer to displace a different volume of gaseous working fluid during a cooling phase of the Stirling cycle than during a heating phase of the Stirling cycle.

Abstract: Methods and apparatus are disclosed for generating power. A thermodynamic air engine is configured to convert heat provided in the form of a temperature differential to mechanical energy. The thermodynamic air engine has a working fluid and a displacer adapted to move through the working fluid. The temperature differential is established across the thermodynamic air engine between a first side of the engine and a second side of the engine. The displacer is directly actuated to move the displacer cyclically through the working fluid in accordance with a defined motion pattern.

Abstract: A Stirling engine (1) includes a reciprocating piston which drives an alternator to provide an electrical output (7). The current signal (7) is measured by a current monitor (60) and a fast Fourier Transform value is produced. The FFT of the current signal (7) has been found to be directly related to the stability of operation of the Stirling engine. As harmonic peaks in the FFT increase, this indicates that the stroke length of the piston is approaching or exceeding a safe maximum. Correction action, such as a reduction in heat to the Stirling engine, can be taken in consequence. A variety of stroke length detectors (110) are also disclosed, for use in combination with, or separately from, the FFT analysis of the current signal (7). Optical and mechanical switches and analogue sensors are disclosed, along with an accelerometer mounted upon the casing of the Stirling engine.

Abstract: A control system for a Stirling engine including the use of a synchronous power converter (“SPC”) which is connected to the terminals of the alternator in a linear alternator/FPSE power system. According to the teachings of the present invention, the attached SPC is small and portable and further ensures that piston and displacer excursion within the system remain within design limits. The system and method are designed such that it is possible to adjust both the voltage amplitude and the waveform frequency at the terminals of the linear alternator. By controlling these operational aspects, both the speed and the range of travel associated with the piston and the displacer in the FPSE can be controlled.

Abstract: A Stirling engine (10, 50, 72) comprising at least one working piston (52) and at least one displacement piston (4), wherein for a power control by means of the transmission of the linear movement of a drive part (2) into the linear movement of a driven part (8), a lever (5) articulately connected to the drive part and the driven part (2, 8) is provided, which lever has an associated displaceable pivot point (7), the bearing point of the lever (5) traveling on the pivot point (7) according to a curve during movement transmission.

Abstract: A driving system (13) comprises a housing (10) having spherical hollow space (11), a rotatable main shaft (14), a driving means (16) and a piston construction (15). The piston construction (15) is rockable about a first rocking axis (15a) in a rectilinear motion backwards and forwards relative to a stationary wall portion (12). The driving means (16) is pivotally mounted in the main shaft (14) about a pivotable axis (16b) which forms an acute angle with the rotatable axis (14a) of the main shaft (14) and is rockably mounted in the piston construction (15) about a second rocking axis (16a), which extends at right angles to the first rocking axis (15a). The first and second rocking axis (15a, 16a) cross the rotational axis (14a) of the main shaft (14) at a common crossing point (11c) centrally in the spherical hollow space (11).

Abstract: A system for supporting lateral loads on a piston undergoing reciprocating motion along a longitudinal axis in a cylinder includes a guide link for coupling the piston to a crankshaft undergoing rotary motion about a rotation axis of the crankshaft where the longitudinal axis and the rotation axis are substantially orthogonal to each other. A first guide element is located along the length of the guide link and includes a spring mechanism for urging the first guide element into contact with the guide link. The spring mechanism includes a first spring with a first natural frequency of oscillation and a second spring with a second natural frequency of oscillation. A second guide element is in opposition to the first guide element.

Abstract: A folded linkage for coupling a crankshaft and a piston undergoing reciprocating linear motion along a longitudinal axis. The folded linkage has a guide link with a first end coupled to the piston. A connecting rod couples the distal end of the guide link to the crankshaft which rotates about an axis that is orthogonal to the longitudinal axis of piston motion and located between the proximal end and the distal end of the guide link. A guide link guide assembly supports lateral loads on the guide link at its distal end. The folded linkage may be applied to couple the compression piston and displacer piston of a Stirling cycle machine to a common crankshaft.

Abstract: The power system for extending the effective range of an electrical vehicle including a non-polluting power generating mechanism for recharging the battery system during vehicle use and providing sufficient electrical energy to an electric motor for constant speed cruising without draining the battery system. The additional power needed for acceleration and hill climbing is provided by a temporary draw on the battery system, and by an increase in the RPM of the heat engine when needed. When the need for additional power is over, the power generating mechanism again recharges the battery system while it provides the energy necessary for continued steady state operation. The power generating mechanism comprises a non-polluting heat engine which is mechanically coupled to an alternator or a generator and a control network for controlling the heat engine and selectively directing the electrical energy generated by the heat engine to the vehicle's electric motor and/or battery supply.

Abstract: A resonantly coupled .alpha.-Stirling cooler has hot and cold variable-volume chambers, a regenerator, and a driver for maintaining reciprocating gas displacement between the chambers. Only the hot side of the cooler is driven; the cold side responds passively by resonant coupling. The phase difference between volume oscillations in the hot and cold variable-volume chambers are altered by adjusting the driving frequency.

Abstract: A Stirling cycle engine and drive mechanism therefor which may be configured in a Beta, Alpha or Gamma configuration for providing increased power output. The drive mechanism provides a dwell of the displacer piston at its top and/or bottom dead center positions of the displacer stroke. The drive mechanism includes adjustable regulatory linkages in order to adjust the dwell and stroke of the displacer piston as well as the phase angle between the displacer and power pistons.

Abstract: A drive for driving a displacer in a cryogenic refrigerator includes a rotatable cam having a cam surface. The cam is rotatable about a pivot point with a cam follower contacting the cam surface. Rotational motion of the cam is converted into reciprocating motion of the cam follower. A displacer rod is coupled between the cam follower and the displacer for transferring the reciprocating motion of the cam follower to the displacer for driving the displacer.

Abstract: A stirling cycle system driving device comprises a circumference cam having a circumferential guiding groove formed in the outer peripheral surface thereof, a piston rod and a displacer rod respectively having a wheel guided along said circumferential guiding groove, a crank case having guiding grooves for guiding said piston rod and said displacer rod only upward and downward, a piston and a displacer, and a cylinder case. According to the present invention, because a crank shaft is not needed, the device can be minified and the quantity of the working fluid can be decreased. Preferably, the device further comprises a following gear connected to the displacer rod and the piston rod, a driving gear engaged with said following gear, and a control motor for driving said driving gear, by which the phase angle between the piston and the displacer can be regulated.

Abstract: The present invention relates to a magnetoelectric resonance engine combining in its construction and operation an Alpha-type Stirling cycle thermal machine and a magnetoelectric resonance mechanism having a broad application to both electric generators and electric heat pumps.

Abstract: A piston engine comprising a piston movable in a recriprocating manner in a cylinder, while during operation a wedge-shaped gap is present between piston and cylinder. The piston divides the cylinder into a first chamber and a second chamber, which communicate with each other through the gap. A stable central position of the piston is obtained by means of the wedge-shaped gap, which mainly determines a pressure difference between the first chamber and the second chamber. A particular application of the piston engine is a cryo-cooler, by means of which, for example, processors of computers are cooled.

Abstract: A power conversion machine which is provided with a spherical housing (10) with piston construction (36,37) having two-double-acting pistons (36) turnable about a first axis (x--x) cooperating with a partition plate (40) tiltable about a second axis (z--z) for defining four work chambers with piston surfaces (36a, 36b) going forwards and backwards. The partition plate is connected forcibly to the piston construction so that the partition plate is subjected to a tilting movement while the piston construction is subjected to turning, without thereby turning the partition plate. Inlet openings and outlet openings which are placed one after the other in communication with the four work chambers, are opened and closed by a control effected by joint movement of the pistons and the partition plate.

Abstract: The present invention relates to a control scheme for power modulation of a free-piston Stirling engine-linear alternator power generator system. The present invention includes connecting an autotransformer in series with a tuning capacitance between a linear alternator and a utility grid to maintain a constant displacement to piston stroke ratio and their relative phase angle over a wide range of operating conditions.

Abstract: The aim of the invention is to improve upon conventional electricity generator sets consisting of a driven generator with relatively complex couplings and possibly a gear box transmission between the crank shaft and the generator.In accordance with the invention the engine is a stirling or hot gas engine with at least four double acting cylinders, each of whose pistons placed between a hot and a cold cycle space is connected with a piston rod on a cross head linearly guided in a cross head guide and coupled via coupling member, more especially one in the form of a connecting rod, with a crank shaft. Furthermore the moving elements--permanent magnets or exciting windings--of a linear generator are located in each cross head and the stationary parts--stators--are arranged on the associated cross head guide. The crank shaft and linking members only serve to synchronize the working cycles of the engine and are therefore only designed for light duty.

Abstract: A Stirling engine design which is solar powered is disclosed. A solar receiver converts solar radiation to thermal energy, which is stored in a storage chamber. The engine includes a displacer chamber with a displacer piston which divides the chamber into hot and cold subchambers, the hot subchamber being heated by the storage chamber. A mechanism is provided for cooling the cold subchamber. The engine also includes an alternator chamber with an alternator piston which divides the chamber into working and bounce subchambers, the working subchamber being in fluid communication with the cold subchamber of the displacer. The working fluid circulates through the cold subchamber and the working subchamber and obtains heat from the storage chamber. The working fluid is displaced by the displacer piston to drive the alternator piston, and work output is obtained from the alternator piston.

Abstract: In a stirling cycle machine a shell means enclosing the machine body for maintaining a substantially sealed atmosphere about the machine body. A diffuser arranged between the machine body and the outer shell for diffusing a shock wave traveling towards the outer shell as the result of an explosive failure of the machine body.

Abstract: In a Stirling cryogenic refrigerator, the movement of the displacer is monitored by sensing the back EMF in the displacer drive coil throughout displacer stroke. The back EMF signal is applied through a feedback circuit to control the phase relationship of displacer movement with a reference signal related to the pressure wave.

Abstract: A linear alternator capable of delivering multi-phase power and yet being driven by a free piston Stirling engine. The alternator has a permanent magnet mounted to the power piston of the free piston Stirling engine and an armature coil member mounted radially outwardly from the piston cylinder for generating one phase. A body, such as a second piston mounted in the same cylinder, is drivingly linked through a spring to be driven by the power piston. A second permanent magnet is mounted to the body and a second armature coil member is formed outwardly of the cylinder disposed outwardly from the body to provide the second phase. Proper design selection of the mass of the body and the spring constant of the spring, together with all other springs connected to the body, causes the body to be driven in phase quadrature with the power piston so that the voltage outputs of the two phases are in quadrature.

Abstract: A Stirling engine design which is solar powered is disclosed. A solar receiver converts solar radiation to thermal energy, which is stored in a storage chamber. The engine includes a displacer chamber with a displacer piston which divides the chamber into hot and cold subchambers, the hot subchamber being heated by the storage chamber. A mechanism is provided for cooling the cold subchamber. The engine also includes an alternator chamber with an alternator piston which divides the chamber into working and bounce subchambers, the working subchamber being in fluid communication with the cold subchamber of the displacer. The working fluid circulates through the cold subchamber and the working subchamber and obtains heat from the storage chamber. The working fluid is displaced by the displacer piston to drive the alternator piston, and work output is obtained from the alternator piston.

Abstract: A Stirling type thermal engine is disclosed in which the engine is sealed within an outer shell enclosure which maintains the engine components in an axially compressed state to thereby simplifying construction of the engine while maintaining a sealed atmosphere of working fluid about the engine thereby minimizing leakage seal problems and also providing a containment enclosure about the engine in the event of explosive failure of the same.

Abstract: In the case of a heat engine, in particular a Stirling engine, comprising a displacement piston and a working piston which are coupled together in a housing sealed in a leak-proof manner against the outside so that they can oscillate in a linear direction, in which case the gas space between the displacement piston and the working piston is connected to the gas space between the displacement piston and the housing by way of a heater, a cooler and a regenerator arrangement to which an external source of heat may be connected, in order to make possible the take-off of mechanical energy from the closed housing for external use, provision is made for one magnetic or magnetizable coupling device (9, 15) located within the housing (1) to be connected at least with the working piston (2) and there is also a corresponding magnetic or magnetizable coupling device (8, 18) outside the housing (1) which is movably mounted in parallel with the piston travel.

Abstract: An externally excited resonant free piston Stirling engine thermal amplifier system which is over damped at all load levels and will not freely oscillate and wherein the displacer/piston system of the Stirling engine is externally driven by a separate drive motor. The system includes means for sensing at least one preselected operating parameter of the Stirling engine thermal amplifier and/or the load driven by the Stirling engine thermal amplifier and deriving feedback signals indicative of such operating parameters. The system further includes feedback means responsive to the operating parameter sensed signals and operative to develop control signals for variably controlling the drive motor to thereby precisely, variably and stably control the operation of the Stirling engine thermal amplifier system.

Abstract: The present invention relates to external combustion engines and more precisely to motors using the Stirling cycle designed to directly convert thermal energy into electrical energy.In accordance with the invention, this transformation is carried out inside a machine which is completely sealed, without a mechanical connection with the outside, in which the power piston drives the moveable part of an electrical generator. In accordance with one preferred embodiment, this electrical generator is a linear alternator. In accordance with a further original feature of the invention, control of the coupling between the displacing piston and the power piston is carried out by using electronic regulation.

Abstract: An improved thermal engine of the type having a displacer body movable between the hot end and the cold end of a chamber for subjecting a fluid within that chamber to a thermodynamic cycle and having a work piston driven by the fluid for deriving a useful work output. The work piston pumps a hydraulic fluid and a hydraulic control valve is connected in line with the hydraulic output conduit such that the flow of hydraulic fluid may be restricted to any desired degree or stopped altogether. The work piston can therefore be controlled by means of a controller device independently from the movement of the displacer such that a variety of engine cycles can be obtained for optimum engine efficiency under varying load conditions. While a Stirling engine cycle is particularly contemplated, other engine cycles may be obtained by controlling the movement of the displacer and work pistons.