Mechatronic design of an active printhead alignment mechanism for wide format printing systems

In this paper, the mechatronic design of an active printhead alignment mechanism for multi-printhead inkjet printers is presented. The position of each printhead can be independently controlled for the purpose of printhead alignment, by which print quality is improved without tightening the manufacturing tolerances. The design of a short stroke movable printhead mechanism with an actuator is discussed, aiming at a positioning accuracy within 10 μm. A dynamic finite element model is developed to determine the eigenfrequencies, mode shapes and transfer functions of the printhead guidance mechanism. The principle is validated in closed loop by various tests with a realized prototype. The experimental results show that static as well as dynamic alignment errors are compensated for within the requirement whereas the manufacturing tolerances can even be lowered.