Driving waveform generating device and method for ink-jet recording head

A driving waveform generating device for an ink-jet recording head, the driving waveform generating device generating at least one presumed driving waveform in order to drive the recording head according to gradation data by utilizing the driving waveform, the driving waveform generating device comprising:

• waveform data storage means having a group of coordinate data for generating the driving waveform;
• waveform data read means for selecting at least one utilizing waveform data from the waveforms and reading the group of coordinate data for the driving waveform;
• waveform data interpolation means for creating the driving waveform by interpolating point-to-point values into the group of coordinate data read by the waveform data read means;
• digital/analog conversion means for subjecting data on the driving waveform created by the waveform data interpolation means to digital/analog conversion in order to output an analog signal;
• and
• signal amplification means for amplifying the analog signal which has been output from the digital/analog conversion means.

A driving waveform generating device for an ink-jet recording head, the driving waveform generating device comprising:

• waveform generating means for generating a predetermined driving waveform for driving a recording head;
• and
• waveform amplifying means for amplifying the driving waveform generated by the waveform generating means and applying the driving waveform thus generated thereby to the recording head, said amplification means including:
• an amplifier circuit including a pair of transistors whose mutual emitters are connected together;
• fixed resistors for always applying a predetermined voltage between the base•emitter to make the pair of transistors operate in an active area;
• and
• a negative resistor element having the same resistance value as that of the fixed resistor is connected in parallel to by-pass the fixed resistor at a reference temperature before the pair of transistors self-generate heat so as to decrease the voltage between the base•emitter when the voltage between the base•emitter rises because of the self-generation of heat on the part of the pair of transistors.

A driving waveform generating method for an ink-jet recording head, the driving waveform generating method for generating at least one presumed driving waveform in order to drive the recording head according to gradation data by utilizing the driving waveform, comprising the steps of:

• retaining a group of coordinate data for generating the driving waveform in waveform data storage means beforehand;
• selecting one utilizing driving waveform from the driving waveforms and reading the group of coordinate data for the driving waveform from the waveform data storage means through waveform data read means;
• creating the driving waveform by interpolating point-to-point values into the group of coordinate data read by the waveform data read means using the waveform data interpolation means;
• subjecting the data on the driving waveform created by the waveform data interpolation means to digital/analog conversion using digital/analog conversion means in order to output an analog signal;
• and
• amplifying the analog signal output from the digital/analog conversion means using signal amplification means.

A driving waveform generating device for an ink-jet recording head, the driving waveform generating device generating at least one presumed driving waveform in order to drive the recording head according to gradation data by utilizing the driving waveform, the driving waveform generating device comprising:

• waveform data storage means having a group of data on partial waveforms for generating the driving waveform;
• waveform data generating means for selecting a plurality of partial waveforms to be utilized out of the group of data on the partial waveforms in order to create the driving waveform by combining the plurality of partial waveforms;
• and
• digital/analog conversion means for subjecting data on the driving waveform created by the waveform data generating means to digital/analog conversion in order to output an analog signal;
• and signal amplification means for amplifying the analog signal which has been output from the digital/analog conversion means.