Abstract: A apparatus and method for throttling a heat engine uses a plurality of cylinder ports through a side portion of the cylinder and a sleeve that selectively opens or closes them to provide fluid communication between an interior portion of the cylinder and a reservoir area when a piston in the cylinder is below the cylinder ports. The sleeve has a plurality of throttle ports through it and moves to communicate a number of the throttle ports with a number of the cylinder ports, thereby opening the cylinder ports. Cylinder ports and throttle ports may be arranged so that as the sleeve is rotated, an increasing number of cylinder ports are opened higher up the cylinder. The cylinder ports may also be arranged so that rotating the sleeve varies the amount ports are opened. The sleeve is preferably worm-gear driven for accurate position control. Upon closing the throttle, normal operating pressures are restored via use of a check valve.

Abstract: A multi-channel thermal regenerator for a heat engine comprising a coiled annulus of thin high-temperature sheet material coiled so that individual coils are in spaced substantially parallel arrangement in an annular configuration. In one embodiment the sheet material is approximately 0.002 inch thick stainless steel embossed in a rectangular array with approximately 0.008 inch high protruding dimples that space the coils. In another embodiment the sheet material is carbon having a plurality of fibers oriented generally circumferentially around the coiled annulus providing a higher thermal conductivity in a direction along the fibers. A ceramic string is woven between the coils radially across the annulus at a plurality of locations around the annulus to space the coils. The coiled annulus is preferably contained in a cartridge having a substantially open cage base with a plurality of bars that space the end of the coiled annulus from adjacent engine structure.

Abstract: A heat engine is constructed from sheet metal and the like. The heat engine has an outer container and inner container which contains a displacer and a power piston. A plurality of positioning members are provided to dimensionally stabilize the inner and outer containers. By providing positioning members that extend between the inner and the outer containers, a sandwiched construction is obtained which allows the inner and outer containers to reinforce each other thus permitting the use of thin walled containers and improving the thermal efficiency of the heat engine and decreasing the weight of the heat engine.

Abstract: A heat engine is constructed from sheet metal and the like. The heat engine has an outer container and inner container which contains a displacer and a power piston. A plurality of positioning members are provided to dimensionally stabilize the inner and outer containers. By providing positioning members that extend between the inner and the outer containers, a sandwiched construction is obtained which allows the inner and outer containers to reinforce each other thus permitting the use of thin walled containers and improving the thermal efficiency of the heat engine and decreasing the weight of the heat engine.

Abstract: A heat engine is constructed from sheet metal and the like. The heat engine has an outer container and inner container which contains a displacer and a power piston. A plurality of positioning members are provided to dimensionally stabilize the inner and outer containers. By providing positioning members that extend between the inner and the outer containers, a sandwiched construction is obtained which allows the inner and outer containers to reinforce each other thus permitting the use of thin walled containers and improving the thermal efficiency of the heat engine and decreasing the weight of the heat engine.

Abstract: A heat engine uses magnetic fields to hold at least one of the displacer and the piston in position and to move the at least one of the displacer and the piston.

Abstract: A heater head assembly for a multi-cylinder heat engine the stirling engine, such as a multi-cylinder Stirling engine, having a plurality of regenerators and cylinders. Each regenerator has a regenerator manifold and each cylinder has a cylinder manifold. First identical cast heater tubes connect the regenerator manifold to first heater tube openings in a heater head manifold. Second identical cast heater tubes connect second heater tube openings in the heater head manifold to the cylinder manifold. The first and second heater tubes are parallel with respect to each other and form a pair of partial concentric staggered arrays. The heater tubes are rotationally asymmetric, having fin sections with less surface area upstream than downstream and thicknesses which decrease radially away from the central passageways of said heater tubes.

Abstract: A heat engine is constructed from sheet metal and the like. The heat engine has an outer container and inner container which contains a displacer and a power piston. A plurality of positioning members are provided to dimensionally stabilize the inner and outer containers. By providing positioning members that extend between the inner and the outer containers, a sandwiched construction is obtained which allows the inner and outer containers to reinforce each other thus permitting the use of thin walled containers and improving the thermal efficiency of the heat engine and decreasing the weight of the heat engine.

Abstract: A Stirling engine which uses a dual pressure shell surrounding the high pressure and temperature engine components. Space between the shells is filled with an incompressible and insulating liquid material, such as a liquid salt. The liquid may have a filler material to prevent excessive movement. The liquid provides a time varying pressure field, driven by the pressure variations in the Stirling engine working fluid, which cancels the pressure differential on heat transfer tubing. The heat transfer tubing is inside of a dome which contains an incompressible, highly thermally conductive liquid, such as Sodium. The heat transfer tubing uses smaller diameter passages contained within a larger diameter body to reduce manufacturing cost and increase reliability. An annular regenerator offers improved efficiency and power levels. A throttling system vents working fluid to a low-pressure container and maintains engine efficiency.

Abstract: A method of combusting fuel and air in a burner of an external combustion engine having a heater head. The fuel and air are combined to form a fuel-air mixture which is characterized by a fuel-air ratio. An exhaust gas product is produced when the fuel-air mixture is combusted in the burner of the external combustion engine. A flame is formed by igniting the fuel-air mixture at a first fuel-air ratio produced by a first air flow rate and a fuel flow rate. The air flow rate is then increased to produce a second fuel-air ratio. The fuel flow rate is also controlled based upon a temperature of the heater head of the external combustion engine. The flame is maintained at the second fuel-air ratio by adjusting the air flow rate based on the fuel flow rate. The external combustion engine may be, for example, a Stirling cycle engine.

Abstract: An apparatus for providing cooling has a heat engine in which the cycle profile of at least one of the displacer and the piston is variable for to provide efficient cooling at various temperature differences.

Abstract: A Stirling machine having two pistons coupled to a harmonic crank drive linkage for providing a specified phase relationship between sinusoidal displacements of each piston with respect to a fixed fiducial point. The harmonic crank drive linkage has a primary crankshaft and an eccentric crankshaft mounted internally to the primary crankshaft and coupled via a gear set to counterrotate with respect to the primary crankshaft. The eccentric crankshaft may be cantilevered with respect to the primary shaft, with the pistons of the engine coupled to the eccentric crankshaft externally to the supporting bearings. A flywheel coupled to the eccentric crankshaft provides for operation of the engine with a zero net angular momentum. An intake manifold provides for mixing air and fuel for combustion heating of the engine.

Abstract: A Stirling cycle machine control system includes an energy converter having a moving member. A detector is operatively associated with the moving member. The detector is configured to detect stroke of the moving member. A converter circuit is coupled with an output of the energy converter and is operative to convert output from AC to DC. A regulator is coupled with the converter circuit and a useful load, and is operative to regulate DC voltage. A controllably variable load member is coupled to the converter circuit and is operative to adjust load to the energy converter. Adjustment of the load to the energy converter regulates power output of the energy converter which in turn controls movement of the moving member. Control circuitry is signal coupled with the detector and the load member. The control circuitry is configured to receive a feedback signal correlated with the detected stroke of the moving member.

Abstract: The invention relates to a thermal machine having a housing (2, 2a, 2a', 2b) which defines an operating space, an operating space, an operating medium which is contained in the operating space, a heat source (6, 6') which is arranged in the housing (2, 2a, 2a', 2b) as well as a heat sink (5, 5') which is arranged in the housing (2, 2a, 2a' 2b), a regenerator (7, 7') which forms an intermediate heat store which is mounted such that it can move linearly in the operating space, and at least one operating piston (4, 13, 14, 20, 20', 25) which is acted on by the operating medium, for outputting mechanical power from the operating space, and for coupling mechanical power from the operating space.

Abstract: A hot and cold engine operating based on a regenerative gas cyclical process, with at least two pistons (2, 3), which separate at least three processing chambers (4, 6, 7) with an in-line arrangement of respectively at least one heat exchanger (13, 15) and at least one regenerator (11, 12) arranged in series with the heat exchanger. In order to eliminate the danger of freezing for the cold heat exchanger (15) and thus the air heat exchanger (16), at least one of the regenerators (12) assigned to the cold processing chamber (6) has a bypass (17) with a control valve (17a).

Abstract: A Stirling cycle engine includes: a housing having at least one cylinder; a motor element disposed in the housing; and a Stirling refrigerator portion driven by the motor element. The cylinder is made to be a cross guide for a piston or a displacer of the Stirling refrigerator portion. Thus, it is possible to provide a desired Stirling cycle engine, for example, a Stirling refrigerator, a Stirling engine generator, etc. with a single configuration.

Abstract: A microminiature Stirling cycle engine or cooler is formed utilizing semiconductor, planar processing techniques. Such a Stirling cycle thermomechanical transducer has silicon end plates and an intermediate regenerator. The end plates are formed with diaphragms and backspaces, one end plate forming the expansion end and the opposite end plate forming the compression end, with the regenerator bonded in between. A control circuit apparatus is linked to the diaphragms for controlling the amplitude, phase and frequency of their deflections. The control circuit apparatus is adapted to operate the transducer above 500 Hz and the passages and the workspace, including those within the regenerator, expansion space and compression space, are sufficiently narrow to provide a characteristic Wolmersley number, which is characteristic of the irreversibilities generated by the oscillating flow of the working fluid in the workspace, below substantially 5 at the operating frequency above 500 Hz.

Abstract: A heater assembly for a heat engine designed to utilize solar energy and heat produced by combustion of a fuel such as natural gas. A receiver housing allows concentrated solar energy to be directed through a receiver aperture into a receiver chamber. Inner and outer arrays of heater tubes within the receiver chamber absorb the solar energy and transfer heat to working fluid in the heater tubes. A burner within the housing produces combustion gases which circulate past the heater tubes and transfer heat to the working fluid. The heater tubes form an opaque surface to solar energy and have uniform gaps which allow heated fluid to be passed between adjacent heater tubes. A precise three-dimensional mathematical description for the centerlines of the heater tubes which maintains uniform gaps between adjacent heater tubes is disclosed.

Abstract: The invention relates to method and an arrangement for utilizing the heat comprised i the exhaust gas of the combustion chamber of a heating and refrigerating engine working on the basis of a regenerative cyclic gas process by preheating the combustion air supplied to the combustion chamber, with the process gas, which is displaced from the hot working volume or supplied to this working volume, flowing through a regenerator arranged inside of a pressure-proof housing in the region of the hot piston. In order to achieve an effective utilization of the exhaust gas heat without additional apparatus complexity and without insulation of the engine in the region of the warm regenerator while maintaining the temperature profile necessary for the operation of the regenerator, the combustion air to the cooling of the pressure vessel wall surrounding the lower section of the regenerator is used, which cooling corresponds to the lower section of the temperature profile of the regenerator.

Abstract: A heater head for use with a thermal regenerative machine has a heater shell formed from a single piece of material. The shell has a tubular body with a cap-shaped end portion provided at a distal end and an open mouth portion provided at a proximal end. The heater head also has a mounting flange with a receiving portion configured to mate in fixed assembly with the open mouth portion of the heater shell. The mounting flange is constructed and arranged to mount the shell assembly to a housing of the thermal regenerative machine. The shell assembly and housing are hermetically sealed there between. Furthermore, a heater head for use with a thermal regenerative machine typically has a heater shell and a heat exchanger portion. The heat exchanger portion is formed substantially from a corrugated piece of sheet metal. The heat exchanger portion is affixed to an inner portion of the heater shell.

Abstract: A hot gas engine operating with a Stirling cycle includes a hot chamber, displacer piston, regenerator, cold chamber, and power piston. A displacer piston is associated with a kinematic transmission train employing non-circular gears so as to convert rotary motion of a mainshaft into longitudinal piston movement and vice-versa. A power piston is associated with a kinematic transmission train employing non-circular gears so as to convert rotary motion of a mainshaft into longitudinal piston motion and vice-versa. The displacer piston and power piston relate to each other so that the engine working gas operates in close accordance with the theoretical four strokes comprising the Stirling cycle.

Abstract: An improved, reciprocating internal combustion engine is disclosed herein. This engine consists of multiple cylinders, each closed by a cylinder head and containing a piston which is connected to a power output shaft. Each cylinder has means for the intake and exhaust of working fluid. It also contains a movable, thermal regenerator, an alternating flow heat exchanger, and means to move this regenerator. Finally, means are provided for the introduction of fuel into the cylinder. The regenerated, internal combustion, reciprocating engine and several variations on it disclosed herein are substantially different from prior art and provide critical improvements over that prior art. These improvements include different and superior heating and cooling strokes.

Abstract: A balanced compound, regenerative cycle, external heat source engine is mad by using mechanically double acting rigidly affixed and self-aligned reciprocating opposed piston and cylinder structure in which substantially all of the energy created during reciprocating motion is converted or translated into rotational motion by the action of a scotch yoke type, transfer lubricated, sliding/roller bearing mechanism which acts on a single and centrally located crankshaft which is contained in a telescopic crankcase structure. A balanced compound engine structure may be constructed so that two or more subsystems are housed in one or more modules. Two or more power modules may then be coupled together and an engine power and speed control may be attained by varying the relative phase angle of the couple.

Abstract: In a Stirling engine, a thermal isolating space is provided between an expansion space and a heating portion so as to establish a thermal isolation of the expansion space from the heating portion.

Abstract: A Stirling engine includes an expansion cylinder, a compression cylinder, and a plurality of conduits which each extend between and connect the expansion cylinder and the compression cylinder. A plurality of heating portions are provided, each of which is disposed in one of the conduits in order to be connected with the expansion cylinder. A plurality of cooling portions are also provided, each of which is disposed in one of the conduits in order to be connected with the compression cylinder. A plurality of regenerative portions are also included, each of which is disposed in one of the conduits in order to connect one of the heating portions and one of the cooling portions. Each of the regenerative portions possesses a length according to the temperature of the working fluid in the corresponding heating portion.

Abstract: A stirling engine including a heat exchanger having a displacer plate, which moves to and fro between two spaced parallel housing plates of the heat exchanger housing and which divides the housing into an expansion chamber and a compression chamber, cooling and heating devices associated with the displacer plate, distributed struts extending between the spaced parallel housing plates and penetrating the displacer plate, and a linear roller diaphragm which guides the displacer plate with respect to the end faces of the housing.

Abstract: In a Stirling engine having a housing chamber (1) which is divided by a reciprocating gas-permeable regenerator plate (4) into two part chambers (6, 7), of which one can be heated and the second is provided with cooling (13), the second part chamber (7) communicating with a working cylinder which acts on a working shaft (14) or a flywheel mass (10) via a first drive device (9) and on the regenerator plate (4) via a second drive device, it is proposed to design the housing chamber (1) in a wedge-shape and to mount the regenerator plate (4) pivotably about a pivoting axis (5) in the tip of the housing chamber. As a result of the proposed design of the housing chamber (1) with the pivotable fixing of the regenerator plate (4) which at the same time serves as a displacement piston, the displacement function of the regenerator plate (4) is fully effected by low-wear pivoting motion about the pivoting axis (5).

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: In a hot gas or Stirling engine conventional regenerators for engines with a large displacement, designed for axially directed flow and usually lacking sufficient mechanical strength with respect to the high working gas pressures, have been replaced by radial flow regenerators. In the respective receiving spaces, the radial flow regenerators are surrounded externally and internally by an annular duct for the supply and discharge of the working gas. Thus, it is possible to ensure a larger flow area for the working gas and to design the engine with the desired mechanical strength.

Abstract: Improved Stirling cycle machine including at least a pair of eccentric disks fixed to a pair of rotatable shafts in phase with each other and which eccentric disks upon rotation of the shafts (in opposite directions in the preferred embodiment) also rotate (in opposite directions in the preferred embodiment) and impart upward movement to a bellows defining a variable-volume compression or expansion chamber with a reduced tendency to also impart side thrust, rocking motion, or lateral movement to the bellows whereby bellows wear is reduced and the life of the bellows and the Stirling cycle machine is increased.

Abstract: A double-acting, rotating piston reciprocating in a cylinder with the motion of the piston providing the valving action of the Sibling Cycle through the medium of passages between the piston and cylinder wall. The rotating piston contains regenerators ported to the walls of the piston. The piston fits closely in the cylinder at each end of the cylinder except in areas where the wall of the cylinder is relieved to provide passages between the cylinder wall and the piston leading to the expansion and compression spaces, respectively. The piston reciprocates as it rotates. The cylinder and piston together comprise an integral valve that seqentially opens and closes the ports at the ends of the regenerators alternately allowing them to communicate with the expansion space and compression space and blocking that communication.

Abstract: A regenerative heat exchanger in which a compact arrangement of alternating thermally conductive and thermally insulating solid layers have an array of communicating passages therethrough. One of the outer thermally conductive layers is heated and the other is cooled. The intermediate thermally conductive layer(s) has a regenerative function when flow is alternated through the passages. Although each passage is preferably small, the total number of passages in the array is such as to give a large combined cross-sectional area for heat transfer providing improved overall performance and efficiency when incorporated in stirling and other heat engines without sacrificing structural integrity.

Abstract: A device by which one can extract low grade thermal energy and transfer that thermal energy from one medium to another utilizing a Stirling engine compressor means, motor means, heat exchanger means and regeneration chamber. The flow of thermal energy between the two heat exchanger means utilized is reversible by the simple change in direction of rotation of the motor means.

Abstract: An internal thermal exchanger engine which, in one embodiment, includes a cylinder having side walls and an enclosed lower end, with a piston mounted for reciprocal movement within the cylinder, and with a heat exchanger reciprocally mounted within the cylinder between the piston and the lower end of the cylinder. A gas phase fluid is enclosed between the piston and the lower end of the cylinder. The heat exchanger, which has perforated end portions, contains a foraminous heat conductive material distributed throughout the entire volume of the heat exchanger, thus allowing the gas phase fluid to pass freely through the heat exchanger as the heat exchanger moves between the piston and the lower end of the cylinder. A solenoid mounted on the piston operates an exchanger rod secured to the heat exchanger so as to cause the heat exchanger to move reciprocally within the cylinder. A combustion chamber is provided at the lower end of the cylinder to provide a source of heat.

Abstract: An external combustion engine is provided with an engine body containing a cylinder, a working fluid within the cylinder, and a displacer piston reciprocable between two ends of the cylinder. A heat exchanger matrix permeable to said working fluid is provided at one end of the cylinder. The movement of the displacer establishes a flow path through a limited portion of the matrix such that the working fluid exchanges heat with different portions of the matrix at different displacer positions as the fluid is displaced between the two ends of the cylinder.

Abstract: A modified Stirling cycle engine is described in which an increase of efficiency is obtained by using the heat transferred by conduction from the walls of the expansion cylinder and the expansion piston and providing a labyrinth dynamic seal at least on the expansion piston.

Abstract: A combustor for use in an external combustion engine having a rotary-type regenerator heat exchanger includes a housing having a combustion chamber, an air chamber, a plurality of first outlet ports, and a first inlet port. A main partition defining the combustion chamber and the air chamber in the housing has a plurality of second outlet ports defined in a peripheral portion thereof and a second inlet port defined in a central portion thereof. An annular regenerator is rotatably supported in the housing, dividing the air chamber into first and second chambers, the regenerator having first and second axially opposite end surfaces and a multiplicity of axial through-holes extending therebetween. First subpartitions define first outlet passages communicating between the first outlet ports, respectively, and the first end surface of the regenerator, and divide the first chamber into air and exhaust sections.

Abstract: A resilient diaphragm using a single non-circular rolling convolution to seal pressure around a pistonlike body. The outer wall of the convolution and the perimeter of the diaphragm have the shape of a racetrack, i.e., of a rectangle with two semicircles added. The rectangle part may be made of sheet metal but at least the curved part of the convolution within the semicircles must be of elastomer material such as a rubber coated fabric. The shape of the inner wall may include some additional curvature so that the two walls can have equal lengths. Production of this diaphragm does not require a full-sized curing mold. When it is used in place of a piston in a Stirling engine, a thermal barrier may be needed to protect the elastomer part from the heat and a configuration is preferred in which the reciprocating diaphragm and an array of slender-column displacing elements form a compact package on opposite sides of a cylindrical wall.

Abstract: A Stirling cycle type engine is disclosed in which a displacer piston and power piston operate within a cylinder due to flow of a working fluid which is heated and cooled by a heater element and a cooler element. The cylinder is divided into an upper expansion chamber and a lower compression chamber by a displacer piston. The lower chamber is defined between the displacer piston and power piston. The upper chamber and lower chamber are connected to one another through a serially interconnected heater, a regenerator and a cooler, whereby the working fluid flows into the lower chamber from the upper chamber or vice versa. The regenerator and the cooler are disposed on one outer peripheral side of the cylinder and vertically aligned therewith. Thus, the radial size of the engine is reduced without reducing its efficiency.

Abstract: A hot gas engine operating with a Stirling cycle includes a cylindrical space filled with a process gas and containing one or two working pistons and one or two displacement pistons moveable longitudinally in relation to each other. The displacement piston or pistons are integrated with the respective regenerator. The working and displacement piston or pistons are associated with transmission gears constructed as thrust crank transmissions so as to convert rotary motion into longitudinal piston displacement motion and vice-versa.

Abstract: A heat exchanger for a Stirling engine has a domed cylinder which serves as a high-temperature cylinder and a regenerator housing. The domed cylinder has a smoothly-changing cross-sectional shape so that stress concentrations will not develop therein. A thin inner liner which is inserted into the domed cylinder divides the inside of the domed cylinder into an expansion space and a regenerator space. A cylindrical regenerator is coaxially disposed inside the regenerator space. A cylindrical cooler is coaxially disposed below the regenerator with its inner surface forming the outer periphery of the compression space of the engine. The expansion space and the regenerator space are connected with one another by a plurality of heater tubes which are secured to the domed cylinder.

Abstract: A regenerator includes a cylindrical body and a plurality of first and second wire mesh screens stacked inside the cylindrical body. Each first wire mesh screen includes a number of interwoven wires that overlap one another at the cross points of the wire mesh screen, with the overlapping wires being compressed at the cross points in the direction in which the wire mesh screens are stacked. Each second wire mesh screen includes a number of interwoven wires that overlap one another at the cross points of the wire mesh screen, the overlapping wires not being compressed at these cross points. The first and second wire mesh screens are stacked in the cylindrical body in such a manner that one or two of the first wire mesh screens is interposed between mutually adjacent ones of the second wire mesh screens.

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 two piston Stirling engine which includes a heat exchanger arrangement placing the cooler and regenerator directly adjacent the compression space for minimal cold duct volume; a sealing arrangement which eliminates the need for piston seals, crossheads and piston rods; and a simplified power control system.

Abstract: A heater head assembly for a Stirling-type engine has a cylinder and a regenerator housing each of which includes a manifold as an integral part thereof, and heater tubes inserted at one end into the cylinder manifold and at the other end into the regenerator housing manifold linking the cylinder and regenerator housing. Each manifold is broadened longitudinally on the heater tube side so that a working gas flow passage defined by the inner wall thereof has a longitudinal width greater than the inner diameter of the corresponding cylinder or regenerator housing. The inner wall of each manifold makes a smooth, gradual and successive transition from the broader portion of the manifold on the heater tube side to the inner wall of the narrower corresponding cylinder or regenerator housing without forming a sudden constriction in the working gas flow passage.

Abstract: Novel hot gas engines and heat pumps are provided which operate on an improved cycle related to the Stirling cycle. These hot gas engines and heat pumps use at least two separate heat exchanger assemblies and a plurality of valves to control fluid flow through the heat exchanger assemblies.

Abstract: The design of a cryogenic regenerator for an isothermal Stirling cycle is based upon separately minimizing the losses due to the static heat mass regenerator material and the thermodynamic losses of the gas transferred through the regenerator. This leads to a sequence of regenerator sections each designed for a given temperature region (temperature difference/temperature=1/2) where the gas flows in a constant width channel in contact with a smooth channel wall. Two alternate designs are given, one with the channel walls of a thin stainless steel backed up by bands of lead and the second using a special alloy of pure lead and roughly 1% of a heavy soft metal such as bismuth or cesium. The composite banded regenerator leads to an overall efficiency relative to Carnot of 50% at 4.degree. K. and 15 Hz and the special lead alloy regenerator leads to 25% efficiency at 4.degree. K. and 30 Hz.

Abstract: A hot gas reciprocating apparatus is disclosed in which a displacer piston and power piston operate within a cylinder due to flow of medium gas which is heated and cooled through a heater and a cooler. The cylinder is divided into a upper chamber and lower chamber by the displacer piston, and the lower chamber is defined between displacer piston and power piston. The upper chamber and lower chamber are connected with one another through the heater, a regenerator and the cooler, whereby the medium gas flows into the lower chamber from the upper chamber or vice versa. The heater, which receives heat from heat sources, projects radially from the cylinder to extend over the heat source; and the cooler projects radially from the cylinder on an opposite side from which heater extends. The heater and cooler are axially spaced from one another along the axis of the cylinder.

Abstract: A Stirling engine capable of utilizing air as a working fluid which includes a compact heat exchange module which includes heating tube units, regenerator and cooler positioned about the combustion chamber. This arrangement has the purpose and effect of allowing the construction of an efficient, high-speed, high power-density engine without the use of difficult to seal light gases as working fluids.

Abstract: A monolithic heater head assembly which augments cast fins with ceramic inserts which narrow the flow of combustion gas and obtains high thermal effectiveness with the assembly including an improved flange design which gives greater durability and reduced conduction loss.