Abstract: An oscillatory rotary engine comprising a toroidal housing having an intake port and an exhaust port. The housing supports an output shaft and a plurality of stacked rotors are disposed within the housing and coupled to the output shaft. Each rotor includes a plurality of pistons disposed in spaced relation to each other about a circumference of the rotor. A resilient coupler connects the rotors to the output shaft. Preferably, the coupler comprises a plurality of nested spiral cuts extending through the rotor. Each piston may include a pawl that is operative to engage ratchets located around the housing, thereby allowing rotation of each rotor in only one direction. The oscillatory rotary engine may further include a compression bypass port that is operative to relieve intake air pressure during compression, whereby the engine has a compression ratio that is less than its expansion ratio.

Abstract: An oscillatory rotary engine comprising a toroidal housing having an intake port and an exhaust port. The housing supports an output shaft and a plurality of stacked rotors are disposed within the housing and coupled to the output shaft. Each rotor includes a plurality of pistons disposed in spaced relation to each other about a circumference of the rotor. A resilient coupler connects the rotors to the output shaft. Preferably, the coupler comprises a plurality of nested spiral cuts extending through the rotor. Each piston may include a pawl that is operative to engage ratchets located around the housing, thereby allowing rotation of each rotor in only one direction. The oscillatory rotary engine may further include a compression bypass port that is operative to relieve intake air pressure during compression, whereby the engine has a compression ratio that is less than its expansion ratio.

Abstract: An oscillatory rotary engine comprising a toroidal housing having an intake port and an exhaust port. The housing supports an output shaft and a plurality of stacked rotors are disposed within the housing and coupled to the output shaft. Each rotor includes a plurality of pistons disposed in spaced relation to each other about a circumference of the rotor. A resilient coupler connects the rotors to the output shaft. Preferably, the coupler comprises a plurality of nested spiral cuts extending through the rotor. Each piston may include a pawl that is operative to engage ratchets located around the housing, thereby allowing rotation of each rotor in only one direction. The oscillatory rotary engine may further include a compression bypass port that is operative to relieve intake air pressure during compression, whereby the engine has a compression ratio that is less than its expansion ratio.