Patent ID: 6811242
Filing Date: 2004-11-02
Classification: B41J,Y10T

Abstract:
A method of detecting a fault within a micro electromechanical device of a type having a support structure, an actuating arm that is movable relative to the support structure between a rest position and an operating position under the influence of heat inducing current flow through the actuating arm and a movement sensor associated with the actuating arm, said movement sensor being activated by movement of the actuating arm to a predetermined position beyond said operating position; the method comprising the steps of:(a) passing a series of current pulses having a varying duration tp through the actuating arm, and (b) detecting for movement of the actuating arm by detecting contact between a moving contact element disposed on the actuating arm and a fixed contact element disposed on the support structure, (c) determining a movement versus pulse duration characteristic for the device, and (d) comparing the determined characteristic with a characteristic for normal operation, wherein normal operation of the device is indicated by no contact between the fixed and moving contact elements below a predetermined pulse duration and contact between the fixed and moving contact elements above the predetermined pulse duration.