Patent ID: 8221698

Claim:
A liquid container comprising: a pressure space; a liquid containing chamber accommodated in the pressure space and storing liquid therein, the liquid containing chamber configured to be pressurized by a pressurized fluid introduced into the pressure space to discharge the liquid therefrom; and a liquid detection portion including: a liquid detection chamber having a liquid inlet port communicating with the liquid containing chamber and introducing the liquid into the liquid detection chamber and a liquid outlet port adapted to be communicated with a liquid consuming apparatus, a volume of the liquid detection chamber being variable; first and second walls opposing each other with the liquid therebetween, a distance between the first and second walls being variable in accordance with the volume of the liquid detection chamber; a detector attached to an outer surface of one of the first and second walls; and a space forming portion configured to form a space between the first and second walls when parts of the first and second walls come in direct contact with each other, the space comprising a portion of the liquid detection chamber, the liquid detection portion configured to be used to detect an amount of the liquid remaining in the liquid container based on a change in residual vibration wave form corresponding to an amount of the liquid remaining in the space, wherein the detector includes: a passage, provided internal to the detector, the passage communicating with the liquid provided in the space of the liquid detection chamber, and a piezoelectric element configured to apply vibrations to the passage.