A 2000 patent by Tang describes a concentric rotor,
individual vanes, and a stator with a cam profile [34].
The stator cam profile is such that there are two intake
and compression sections and two expansion and
exhaust sections as illustrated in Figure 8. There are
two external combustion sections located between the
compression and expansion sections, resulting in two
combustion pulses per revolution. This design
incorporates the Atkinson cycle. The vane is pined with
roller-follower in the end plates, similar to designs
described above. Sealing is mentioned but not detailed.