Stirling type engine and method for operating same

Claim 1

In a Stirling cycle type engine having a cylinder provided with a hot end portion containing a displacer plunger and an opposite end portion containing a power piston, with a cold space between the piston and plunger for cyclically causing gas in the cold space to compress and then move into the hot end portion for heating and expansion to thereby drive the plunger and piston away from the hot end portion, and following which the heated gas returns to the cold space, the improvement comprising: gas exhaust and inlet ports communicating with said cold space, and valve means normally closing said ports, and means for opening the exhaust port valve means for exhausting the heated gas returned to said cold space and thereafter for opening the inlet port valve means for recharging the cold space with gas prior to the compressing of the gas in said cold space.

Claim 12

A method of making an externally heated, Stirling cycle type engine comprising the steps of: beginning with a conventional, small size, 4-cycle engine construction having a cylinder, with a housing block, a crankcase, and a crankshaft within the crankcase connected to a power piston arranged within the cylinder for reciprocation therein, and valved inlet and exhaust ports opening into the cylinder above the piston, i.e., remote from the crankshaft; adding an extension cylinder to the first mentioned cylinder in place of the conventional cylinder head, and providing a displacer plunger within the extension cylinder to form a cold space between the plunger and piston, with the inlet and outlet ports communicating with said cold space; providing means for heating the end portion of the extension cylinder which is remote from the cold space; and providing timing means operably timed to the piston for timing the reciprocating movement of the plunger relative to the piston; whereby the engine operates according to a modified Stirling cycle including the normal cycle steps of the plunger and piston moving towards and away from each other with the gas moving from the cold space to the hot end portion of the extension cylinder and back, but with the addition of the heated gas, upon entering the cold space from the extension cylinder hot end portion, being exhausted and replenished by fresh gas during which time the plunger remains stationary and the piston moves toward the plunger for the exhaust and away from the plunger for the replenishing of the gas.

Claim 13

A method of making an externally heated, Stirling cycle type engine comprising the steps of: beginning with a conventional, small size, 4-cycle engine construction having a cylinder, with a housing block, a crankcase, and a crankshaft within the crankcase connected to a power piston arranged within the cylinder for reciprocation therein, and valved inlet and exhaust ports opening into the cylinder above the piston, i.e., remote from the crankshaft; adding an extension cylinder to the first mentioned cylinder in place of the conventional cylinder head, and providing a displacer plunger within the extension cylinder to form a cold space between the plunger and piston, with the inlet and outlet ports communicating with said cold space; providing means for heating the end portion of the extension cylinder which is remote from the cold space; and providing timing means operably timed to the piston for timing the reciprocating movement of the plunger relative to the piston; whereby the engine operates according to a modified Stirling cycle including the normal cycle steps of the plunger and piston moving towards and away from each other with the gas moving from the cold space to the hot end portion of the extension cylinder and back, but with the addition of the heated gas, upon entering the cold space from the extension cylinder hot end portion, being exhausted and replenished by fresh gas during which time the plunger remains stationary and the piston moves toward the plunger for the exhaust and away from the plunger for the replenishing of the gas.