Patent ID: 7438029

Claim:
An assembly comprising: at least one piston; a rotating member; a transition arm coupled to the at least one piston and the rotating member to translate between rotational movement of the rotating member and a first linear motion of the piston; and a mechanism configured to superimpose a second linear motion of the piston onto the first linear motion of the piston, wherein the mechanism comprises: a cam; a cam-follower coupled to the rotating member and the transition arm, the cam-follower configured to engages the cam during rotational movement of the rotating member; and a pivot member, wherein the pivot member coupled the cam-follower to the rotating member and the transition arm, the pivot member configured to linearly move the transition arm as the cam-follower engages the cam during rotational movement of the rotating member, the linear movement of the transition arm resulting in the second linear motion superimposed on the first linear motion of the piston.