Wiper-type sealing means in the first and
second rotor are incorporated for sealing the chambers.
One version of this mechanism is illustrated in Figure 11.
The 1984 Wankel-designed axed rotary piston engine
uses a piston rotor that travels through a circular
annulus that is created by an inner casing and an outer
radial casing. This design uses an inner stator and an
outer stator with two rotors within the stator housings.
The piston rotor has internal teeth that mesh with the
external teeth of the sealing rotor. This type of rotary
engine is most beneficial when used as a supercharger
or compressor