US Patent 6874452 Resonant combustion chamber and recycler for linear motors

A combustion chamber system for a spark-ignited linear motor includes an open-ended primary combustion chamber located within a secondary combustion chamber. An unrestricted opening between the primary and secondary combustion chambers provides for more efficient scavenging of combustion byproducts. A compression wave trigged by a spark-ignited flame front within the primary combustion chamber is reflected within the secondary combustion. Upon return, the compression wave effectively closes the unrestricted opening of the primary combustion chamber by colliding with the flame front and forcing flame jets through smaller openings in the primary combustion chamber into the secondary combustion chamber for accelerating combustion within the secondary combustion chamber.