Ink remaining amount measuring device, ink-jet recorder comprising same, ink remaining amount measuring method, and ink cartridge

Abstract

In order to provide an ink level detecting unit of an ink jet recording apparatus, which detects surely residual vibration by resonance with a medium such as ink coming into contact with a vibration element without receiving influences such as noise, thereby to heighten ink detection accuracy and reliability, there are provided a piezoelectric element 12 provided in an ink tank 11, an excitation pulse generating part 13 for applying an excitation pulse to the piezoelectric element 12, a sensor 14 which detects a frequency of a counter electromotive force waveform from the piezoelectric element 12 based on residual vibration by resonance with a medium in the ink tank 11, and a judgment part 15 which judges the existence of ink on the basis of the detected frequency. The sensor 14 has two band pass filters 22A and 22B which cause only waveforms in the predetermined frequency bands that have been previously assumed according to ink presence and ink absence to pass; and a frequency measuring part 150 which binarizes the counter electromotive force waveform, counts the number of pulses of the binarized counter electromotive force waveform, counts time from the predetermined number-th pulse to the predetermined number of pulse, and detects a frequency of the counter electromotive force waveform on the basis of this time. An ink remaining amount measuring device for an ink-jet recorder having high ink measuring accuracy and high reliability by accurately measuring the residual vibration due to resonance between a vibration element and a medium such as ink in contact with the vibration element without being influenced by noise. The ink remaining amount measuring device comprises a piezoelectric element (12) provided in an ink tank (11), an excitation pulse generating section (13) for applying an excitation pulse to the piezoelectric element (12).

Description

technical field [0001] The present invention relates to an ink level detection unit and an ink level detection method of an inkjet recording device, and more particularly to a technique for detecting a change in acoustic impedance and thereby detecting an ink level in an ink tank of an inkjet recording device. Background technique [0002] In general, an inkjet recording apparatus includes a carriage on which an upper inkjet recording head and nozzle openings are mounted. The inkjet recording head has a pressure generating means for pressurizing a pressure generating chamber. The pressurized ink flows from the nozzle openings as ink droplets. is ejected in the middle; and an ink tank containing ink to be supplied to the recording head through the flow channel is also included. The inkjet recording apparatus is configured to perform continuous printing. [0003] Here, the ink tank is generally configured as a cartridge detachable from the recording apparatus so that the user...

AI Technical Summary

Problems solved by technology

[0011] Thus, in the case of detecting the presence of ink in the ink tank based on the detection signal of this residual vibration, since the level of the detection signal is lowered, the ink level detection unit is susceptible to noise such as the motor of the inkjet recording apparatus or the head drive waveform. The effect of noise caused by the induction of

As described above, the ink level detection unit that detects the presence of ink based on the remaining vibration frequency of the vibrating element is sensitive to noise, and thus has the problem of low detection accuracy and occasional difficulty in a noisy environment

[0012] Also, in such an ink level detection unit, when the liquid level position of ink is almost equal to the position of a vibrating element such as a piezoelectric element as a sensor element (when the liquid level is in the boundary region between ink presence and ink shortage) , In the case where foam and fluctuations in the liquid level of the ink are generated with the movement of the carriage, there is a possibility of falsely detecting the presence of ink

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