Vane type rotary devices can be summarized as a vane
that oscillates through a rotation due to a prescribed
cam profile as the mechanism rotates. The majority of
these devices are radial vane, where the vane(s)
reciprocate in the radial direction. However, an axial
translation of the vane is also possible. These
mechanisms generally contain a round rotor (disk) with
equally spaced vane slots. Generally, a shaft is centrally
located in the rotor and provides for the power output.
The cam housing is the same nominal height of the rotor
and encompasses the rotor periphery. The cam profile
(radial distance from the shaft’s centerline in a radial
vane design) varies as a function of angular location.
End plates enclose the housing and rotor assembly. A
working volume is generated between the rotor’s face,
two adjacent vane faces, cam wall, and end plates. The
vanes are positioned, through the cam profile, so that
the leading vane (in the direction of rotation) has a
greater exposed surface area than the lagging vane.
The pressure on the exposed vane faces is transferred
to the rotor as a net force, which then results in a net
torque to the shaft.