Method and system for automatically sensing the size of print medium in a printing device

Abstract

A resonance chamber is provided in a printing device, or in a print medium supply tray of the printing device, to determine the size of the print medium in the printing device. The supply of print medium and the resonance chamber are positioned so that the print medium covers a portion of the resonance chamber. An audio signal system then emits an audio signal to drive the resonance chamber. The frequency of the audio signal is varied until the natural resonance frequency of the chamber, as partially covered by the print medium, is discovered. The resonance frequency of the chamber will correspond to the amount of the chamber that is covered by the print medium and, hence, to the length (or width) of the print medium. In this way, the size of the print medium, whether standard or custom, can be determined.

Dependencies are inferred from the claim text.