Resistance measurement method for testing type and quality of inks in color printer reservoirs; involves integrating capacitative branch, including reservoir, into oscillatory circuit

摘要

When an ink reservoir (112) associated with a print head (113) has been changed, a selector switch (125) is used to include it in a circuit branch connected between a maximum detector (115) and an oscillator (117) and in parallel with inductive and capacitative branches (124,126). The parallel branches act as a rejector circuit. A processor (100) uses the maximum detector voltage signal to determine the ink resistivity and its suitability. Independent claims are included for a device for implementing the method, an office automation machine incorporating the device and a microcomputer incorporating the device.