Automatic printhead-to-media spacing adjustment system

An inkjet printer service station has a movable member that interacts with another printer subsystem, which is changeable between a first state and a second state. To vary the printhead-to-media spacing to accommodate different thickness of media, such as plain paper and envelopes, a cam-operated locking mechanism and a lever-operated mechanism raise and lower the inkjet printhead. Other printer subsystems may be transitioned between two or more states through motion of a service station movable member, including motion using gravity assist, centrifugal forces, or momentum to accomplish one of the transitions. Other locking mechanisms may be used to secure a subsystem in one state or another, such as electrical or electromechanical mechanisms, as well as other structurally equivalent forms beyond the specific preferred embodiments illustrated herein without departing from the broad concepts disclosed. An inkjet printing mechanism having such a system, along with methods of operation are also provided.