Abstract: A combustor for a heat engine, such as a Stirling cycle heat engine, incorporating a number of nozzles mounted between a pair of plates. Fuel is introduced from above the plates into mixing chambers within the nozzles. Combustion inlet air passing between the plates is introduced into the mixing chambers and create a swirling motion in the fuel/air mixture. The fuel/air mixture passes through an expansion chamber before being discharged to a common combustion chamber. The combustor has been designed to allow the use of high temperature combustion inlet air and to have low NOx emission characteristics.

Abstract: An actuating mechanism for adjusting the swashplate angle in a Stirling cycle engine. A stationary mounted motor is used to drive one member of a planetary gear set. The motion of this member is transmitted through a second planetary gear set to a member connected to the swashplate. In one embodiment, a worm gear powered by a stationary mounted electric motor drives a moveable rear ring gear. The movement of the rear ring gear is transmitted through three rear planet gears and a common sun gear to produce relative movement in a front planet gear carrier. The relative movement of the front planet gear carrier is transmitted through a bevel gear to the swashplate. This embodiment allows the off-line production of swashplate actuator subassembly cartridges that can quickly be journalled to the drive shaft, joined to and properly phased with respect to the swashplate and meshed with a worm gear connected to the stationary electric motor during the assembly of a Stirling engine.

Abstract: A crosshead system for a swashplate engine such as a Stirling cycle type. A plurality of crossheads are constrained to move in a reciprocating fashion by travelling along a pair of parallel guide rods. The crosshead system further includes a mechanism for adjusting a clearance between the crosshead elements and the opposed parallel face surfaces of the rotating swashplate. The adjustment mechanism includes a threaded adjuster cup which is maintained in a lock position through a fastener which drives a conical cone into the conical inside surface of the adjuster sleeve thus fixing its rotated and hence linear position.

Abstract: A mechanism for elevationally driving a solar concentrator pivotally mounted on a pedestal between a zenith facing position, a horizon facing position, a downward facing position, and any intermediate position, using a single linear actuator. A lower bar is pivotally connected to the pedestal and an upper bar is pivotally connected to the solar concentrator. The lower bar and the upper bar are connected to a slider having a follower nut section which is driven by a linear actuator, having a motor driven lead screw, which is attached to the pedestal or an offset support structure portion of the solar concentrator.

Abstract: A diffuser to be used with a solar energy concentrator and a solar energy receiver to more uniformly distribute solar energy to the receiver and to reduce the amount of energy lost due to circulation of air into and out of the receiver. A portion of the solar energy passing through the energy diffusing cavities within the diffuser is reflected by the cavity walls and reoriented and diffused before being emitted to the receiver. The geometry of the energy diffusing cavities and the reflective characteristics of the cavity walls can be engineered to provide the desired degree of diffusional effect. The diffuser reduces the likelihood of inadvertent hot spots being formed, which allows the designed maximum receiver energy flux to be closer to the receiver tube material limits and allows for smaller, more compact, more efficient receivers. The diffuser also limits the circulation of air in the vicinity of the receiver tubes, which reduces energy losses and increases the overall efficiency of the system.

Abstract: A stirling engine having multiple mutually parallel distant cylinders which operates in a double acting cycle configuration. The engine includes a drive case having a rotatable drive shaft which is mounted to a cylinder block. The cylinder block includes mutually parallel cylinder bores and mutually parallel cooler bores. A generally flat retainer plate is mounted to a flat mounting surface of the cylinder bore to affix cylinder extensions and regenerator housings to the block mounting surface in alignment with the cylinder bores and regenerator bores.

Abstract: A Stirling engine having a modular construction including a drive case and a cylinder block with generally flat mounting surfaces that face each other. The cylinder block includes cylinder bores and cooler bores that are perpendicular to the cylinder block mounting surface. Piston rods extend through the plane defined by the cylinder block mounting surface and couple piston assemblies positioned within the cylinder bores to a drive shaft. Piston rod seals contain a working gas present within the cylinder block from leaking into the drive case. The same basic engine components may be used with either sliding contact rod seals or bellows or other types of hermetic sealing elements.

Abstract: A Stirling engine having multiple mutually parallel cylinders which operate in a double acting cycle configuration. The engine includes a drivecase having a rotatable driveshaft coupled to the pistons which is mounted within the cylinder block. The cylinder block includes cylinder bores and mutually parallel cooler bores. A generally flat retainer plate is fastened to a mounting surface of the cylinder block to affix cylinder extensions and regenerator housings to the block mounting surface in alignment with the cylinder bores and cooler bores.

Abstract: A Stirling engine having a cooler, regenerator and heat exchanger stacked end to end along with a working cylinder position adjacent to the heat transfer stack and connected thereto by several connecting ducts. By using more than one hot connecting duct, their bending stiffness is less as compared with a single duct being the same area as the multiple ducts, allowing thermally induced relative displacement between the elements to occur. The heat exchanger includes a plurality of axially extending tubes spaced apart from one another with a combustor positioned adjacent to the tubes such that the combustion gases flow between the tubes. The tubes are preferably flattened in the direction of the gas flow between them to increase the surface area for heat transfer. Furthermore, wire is coiled around and brazed to the tubes creating a fin for additional heat transfer.

Abstract: A cogeneration system is disclosed using a Stirling cycle engine in which the waste heat from the engine and a generator driven by the engine is used for space heating or producing hot water and the generator used to produce electricity. A Stirling engine has numerous advantages over a reciprocating internal combustion engine in cogeneration systems in that the Stirling engine has a longer life, less maintenance cost, less noise and vibration and fewer emissions. With cogeneration, the added energy and fuel required over and above that required to produce a comparable amount of heat allowed to produce the same amount of heat with a conventional furnace or boiler is often less than the amount of electric energy produced from the system thereby resulting in a efficiency greater than 100% in the production of electricity.

Abstract: Stirling cycle heat engine adapted for use as space heating and/or air conditioners. One embodiment features a Stirling engine prime mover providing a hybrid Stirling machine. Another embodiment utilizes an electric drive motor as a prime mover and a final embodiment is an open drive Stirling thermal engine particularly adapted for automotive belt driven applications. Enhancements in performance are provided by using pressure ratios significantly lower than that ordinarily provided for Stirling cycle engines. Decreases in pressure ratios are provided by intentionally adding dead volume to the cycle and particularly adding this dead volume strategically in the regenerator of the device which has been found to provide performance benefits. The systems according to this invention can be used either as space heaters or air conditioners by appropriately directing heat absorbed and rejected from the heat exchangers of the device to the approrpriate environment.

Abstract: An actuating mechanism for controlling the swashplate angle in a Stirling cycle engine or other engine having parallel reciprocating pistons. The actuation system uses an electric motor for changing swashplate angle. Various embodiments for gear trains for communicating rotation of the electric motor rotor to the swashplate are described. In a first embodiment, a planet gear carrier is driven by the motor and the planet gears simultaneously mesh with two ring gears having a differing number of teeth. Rotation of the carrier creates a high reduction drive for the second ring gear. In accordance with a second embodiment, the ring gear carrier is permitted to freely rotate and a driving sun gear is provided which meshes with the planet gears.

Abstract: A Stirling engine having multiple cylinders arranged in a square cluster with a gas combustor devices for each cylinder integrated into the engine. The combustor devices include individual combustion chamber tubes for each of the cylinder of the engine. Air is introduced into the chambers in a manner which generates a tangential air flow which mixes with a combustible gas injected from a gas nozzle in the center of the tube which provides a highly turbulent combustible gas flow regime. Combustion gases pass through the Stirling engine heat exchangers to transfer heat to the engine. Exhaust gas heats inlet air through a counterflow heat exchanger. The relatively small size of the combustion chamber tubes enables the components of the combustion chambers to reach an equilibrium temperature repidly and minimizes thermal distortion of the components.

Abstract: A solar collector particularly for receiving concentrated solar energy from a large parabolic reflector and which forms the evaporator of a heat pipe type heat transfer mechanism. The solar collector is formed from a pair of spherical shell portions which are joined at their perimeters such that they are nearly tangent at their joint. This configuration provides low mechanical stresses on the welded joint, making the structure resistant to creep failure. The inside surfaces of the solar collector are preferably covered with wire screens for the transport of liquid heat pipe working fluid. Various finenesses of mesh can be used. Preferably, a coarse mesh is in intimate contact with the inside surfaces of the collector to act as a transport medium with a finer mesh covering it. These mesh layers can be applied to surfaces of sheet metal blanks through sintering or other processes which are thereafter deformed to the desired shell configurations.

Abstract: A diffuser unit for allowing non-condensing gases collecting within a heat pipe to be eliminated. The embodiments described herein define a cavity for collection of non-condensing gases such as hydrogen. The housings are arranged such that the heat pipe working fluid in vapor form transfers heat to the walls of the housing defining the collection cavity to raise the wall temperature thus increasing its permeability to the non-condensing gas. Accordingly, when the heat pipe is used in applications where non-condensing gases such as hydrogen tend to diffuse into the heat pipe such as when it is directly heated by a hydrocarbon combustion, such non-condensing gases can be readily eliminated. Such diffusion of non-condensing gases occurs without the requirement of providing a conventional "getter" which uses special material for absorbing or breaking down such non-condensing gases.

Abstract: An improved conduit assembly for coupling a heat pipe evaporator with a Stirling engine heat exchanger. The conduit assembly features a cylindrical main tube section connected to a flared shell joining the heat exchanger of the Stirling engine. The flared shell provides an increasing cross-sectional area which reduces the velocity of vaporized heat pipe working fluid flowing from the heat pipe evaporator to the heat exchanger. Such reduced velocity has been found to minimize entrainment of liquid within the transmitted vapor. The conduit assembly further includes an internal small diameter liquid return duct which provides additional isolation of the liquid and vapor phases of the heat pipe working fluid as a means of further reducing entrainment. Surface tension breakers are provided which communicate the heat exchanger to the inlet end of the liquid return duct to wick away liquid working fluid from the heat exchanger.

Abstract: A bearing arrangement particularly useful for supporting the driveshaft of a thermal engine in which the driveshaft is acted upon by a rotating bending load. Since a rotating bending load of such thermal engines generates driveshaft bending deflections which rotate with the driveshaft, the bearings supporting the driveshaft must be capable of accommodating such deflection. Conventional rolling element type bearings can accommodate driveshaft deflection or wobble but have limited operational lifespans. In accordance with this invention, a driveshaft bearing arrangement is provided utilizing plane bearings having spherical surfaces which restrain radial loads while accommodating driveshaft wobble. In one embodiment, the spherical bearing includes a ring member affixed to the driveshaft having a spherical outer surface which closely conforms to a concave bearing surface.

Abstract: Improved lubricant control assemblies are disclosed for reciprocating piston rods of an engine which prevent crankcase lubricant intruding into the cylinders and fluid from the cylinders from escaping into the crankcase. Each assembly comprises a tubular sleeve fitting closely onto a piston rod and yieldably mounted within the bore between cylinder and crankcase through which the piston rod extends. The sleeve is urged into forceful contact around the piston rod by a plurality of disk members which forcefully urge the sleeve in contact around the piston and for controlling lubrication.

Abstract: A combination gas combustor and heat pipe evaporator comprised of elongated cylindrical tubes which overfit one another to create a number of longitudinal gas flow passages. A burner disposed at one end of the device creates hot flue gases which travel initially through an annular passage where heat is conducted to the working fluid of a heat pipe evaporator chamber. The flue gas flow is then reversed in direction to heat the radially outer surface of the tubes making up the heat pipe evaporator, and thereafter flow through passages to warm inlet air to increase combustion efficiency. For both described embodiments, a bellows is provided to accommodate differences in thermal expansion between the tubes making up the heat pipe evaporator. In accordance with a first embodiment, the primary flue gas transport channel has a decreasing annular width with distance from the combuster which results in a lowering Reynolds number for flow which provides a more uniform heat flux along the length of the device.

Abstract: A solar evaporator for use with Stirling engines consisting of a dish shape hollow body having wicking containing a vaporizable liquid heating medium. The body has a pair of separate chambers to reduce the distance that capillary pressure is required to pump the heating medium and the chambers are thermally coupled by the wicking so that the temperatures in the chambers is at all times equalized.