Abstract: An apparatus for effecting the lubrication of expansible chamber devices of the type having a cylinder with a piston reciprocating therein and having fluid flowing in and out of the chamber. The invention is particularly suitable for free piston Stirling engines and pumps. A torque force is applied to the piston causing it to spin sufficiently to entrain and drag along its outer surface some of the fluid in the expansible chamber so as to separate its outer surface from the wall of the cylinder.

Abstract: A torsionally flexible seal formed with alternating layers of elastic and reinforcing material provides a gas-tight barrier between a drive shaft and a portion of the Stirling engine housing surrounding a passageway through which the drive shaft extends. The shaft is connected to a series of mechanical linkage devices located within the housing which transmits power between the linearly reciprocative power piston and rotationally reciprocative drive shaft and which eliminates substantially the side forces exerted on the piston.

Abstract: The displacer and piston of a Stirling engine are provided with inner cylindrical walls which serve as bearing surfaces in close fitting, sliding engagement with the outer bearing surface of a longitudinally extending, tubular center post. The internal bore of the center post is in fluid communication with the bounce space. Center porting is provided by passages in the piston, displacer and tubular wall of the center post so that fluid communication is provided periodically between the work space and bounce space and between the displacer gas spring and the bounce space. In this manner, the piston and displacer remain properly positioned within the engine housing.

Abstract: A drive mechanism is disclosed for drivingly connecting two reciprocating bodies to a rotating body and is particularly useful for linking a single pin crank of a crank-type Stirling engine to its displacer and power piston. The drive means has at least two slotted yokes, each connected to a different one of the reciprocating bodies such as the pistons of the Stirling engine. The pin of the crank extends through the slots of both slotted yokes. The slots are transverse to each other and preferably are linear.

Abstract: A mechanism is disclosed for driving the displacer of a crank-type Stirling engine at the same frequency but out of phase with the power piston of the engine. A biasing means is linked to the displacer for applying a biasing force which urges the displacer in one direction of its reciprocation. A flexible band is secured to the displacer for applying a force opposite to the biasing force. The other end of the band is secured to an anchor which is mounted on another part of the apparatus. The band extends slideably across at least one and preferably two bearing surfaces intermediate its secured ends.

Abstract: This invention relates to a free piston Stirling engine in which a structure for aiding in the lubrication of the engine is provided. The piston of the Stirling engine is provided with turbine surfaces, such as blades. Working fluid entering the cylinder chamber applies a spin torque to the piston thereby causing the piston to spin and entrain gas about its perimeter for hydrodynamic gas lubrication.

Abstract: A free-piston Stirling engine having a double acting, gas spring system for applying bi-directional, resilient spring forces to the displacer piston rod and also a free-piston Stirling engine having a displacer and power piston which are mechanically resonant at the operating frequency of the engine. The springing system is a gas containing compartment which is formed in communication with the effective end of the displacer rod. An adjustable spool valve arrangement may be formed in the mating walls of the displacer rod and its cylinder for connecting the gas containing compartment with the bounce space during a relatively minor interval of the displacer rod stroke intermediate its extremes for adjustably maintaining the mean position of the displacer at the position at which the interconnection occurs.

Abstract: A solar energy collector for use primarily in a closed-loop system has a fluid conduit of serpentine configuration which comprises a plurality of relatively thin extruded aluminum tubes, each tube having a flat top and bottom wall and lateral flat lips or flanges extending longitudinally along opposite sides thereof and coplanar with the bottom wall forming therewith a flat base for the tubes, the flanges providing means for joining the tubes by welding in an array in side by side abutment relation. Sections are formed from the flat tubing as connecting headers which are welded at both ends to pairs of adjacent tubes in staggered relation to form the continuous serpentine path for the heat transferring fluid.