Dynamics of a Cleaning Blade Based on a 2DOF Link Model

To analyze the dynamics of a cleaning blade in a laser printer, observation of the vibration of the cleaning blade and analysis of a 2DOF model have been carried out. First, from the observation of the vibration of the actual cleaning blade, the stationary self-excited vibration has been confirmed. Next, a 2DOF model has been presented and its governing equations have been derived. The bottom of the model is assumed to always contact a floor surface, and the friction coefficient is constant and not dependent on the floor velocity. Third, by solving the equations governing the motion of the 2DOF model, five patterns of static equilibrium states have been obtained. Moreover it has been clarified from linear stability analysis that one of five patterns corresponds to the shape of the cleaning blade and is unstable for a small disturbance in a narrow region. This unstable vibration is a bifurcation classified as Hamiltonian-Hopf bifurcation. Fourth, by keeping up to the 3rd order terms, the nonlinear complex amplitude equation has been obtained, and the steady amplitude can be decided. As a result, the steady amplitude has been determined as the products of the 2nd order terms. Furthermore it has been clarified that such a self-excited vibration is classified as the supercritical bifurcation.© 2009 ASME