Liquid discharge apparatus, drive waveform generating device, and head driving method
A liquid discharge apparatus includes a liquid discharge head to discharge liquid and control circuitry to generate a drive waveform including drive pulses applied to the head. The drive waveform includes a non-discharge pulse not to discharge the liquid and a discharge pulse to discharge the liquid. The non-discharge pulse and the discharge pulse are serial in time in the drive waveform. Td is in a range of Tc−0.2×Tc to Tc+0.45×Tc. Vp 1 is in a range of −10% to +10% of Vpp 1 . Td represents a time interval between the non-discharge pulse and the discharge pulse. Tc represents a natural vibration period of a pressure chamber of the head. Vp 1 represents a peak value of the non-discharge pulse. Vpp 1 represents a peak value of the non-discharge pulse at which a droplet speed of liquid discharged by the discharge pulse takes a local minimum value.
1. A liquid discharge apparatus comprising:
a liquid discharge head configured to discharge liquid; and
control circuitry configured to generate a drive waveform including a plurality of drive pulses applied to the liquid discharge head,
the drive waveform including a non-discharge pulse not to discharge the liquid and a discharge pulse to discharge the liquid, the non-discharge pulse and the discharge pulse being serial in time in the drive waveform,
Td being in a range of Tc−0.2×Tc to Tc+0.45×Tc, and
Vp 1 being in a range of −10% to +10% of Vpp 1 ,
where Td represents a time interval between the non-discharge pulse and the discharge pulse, Tc represents a natural vibration period of a pressure chamber of the liquid discharge head, Vp 1 represents a peak value of the non-discharge pulse, and Vpp 1 represents a peak value of the non-discharge pulse at which a droplet speed of liquid discharged by the discharge pulse takes a local minimum value.
2. The liquid discharge apparatus according to claim 1 ,
wherein Td is in a range of Tc−0.1×Tc to Tc+0.25×Tc.
3. The liquid discharge apparatus according to claim 1 ,
wherein Td is in a range of Tc−0.07×Tc to Tc+0.2×Tc.
4. The liquid discharge apparatus according to claim 1 ,
wherein Vp 1 is in a range of −7.5% to +7.5% of Vpp 1 .
5. The liquid discharge apparatus according to claim 1 ,
wherein Vp 1 is in a range of −5% to +5% of Vpp 1 .
6. The liquid discharge apparatus according to claim 1 ,
wherein the non-discharge pulse includes:
an expansion waveform element to expand a pressure chamber;
a holding waveform element to hold an expanded state of the pressure chamber; and
a contraction waveform element to contract the pressure chamber from the expanded state of the pressure chamber held by the holding waveform element, and
a holding time in which the holding waveform element holds the expanded state of the pressure chamber is shorter than Tc.
7. The liquid discharge apparatus according to claim 1 ,
wherein the drive waveform includes a plurality of discharge pulses, and the discharge pulse is a last pulse of the plurality of discharge pulses.
8. A drive waveform generating device comprising:
a liquid discharge head configured to discharge liquid; and
control circuitry configured to generate a drive waveform including a plurality of drive pulses applied to the liquid discharge head,
the drive waveform including a non-discharge pulse not to discharge the liquid and a discharge pulse to discharge the liquid, the non-discharge pulse and the discharge pulse being serial in time in the drive waveform,
Td being in a range of Tc−0.2×Tc to Tc+0.45×Tc, and
Vp 1 being in a range of −10% to +10% of Vpp 1 ,
where Td represents a time interval between the non-discharge pulse and the discharge pulse, Tc represents a natural vibration period of a pressure chamber of the liquid discharge head, Vp 1 represents a peak value of the non-discharge pulse, and Vpp 1 represents a peak value of the non-discharge pulse at which a droplet speed of liquid discharged by the discharge pulse takes a local minimum value.
9. A head driving method of driving a liquid discharge head, the method comprising:
generating a drive waveform including a plurality of drive pulses applied to the liquid discharge head; and
applying the drive waveform to the liquid discharge head to discharge liquid,
the drive waveform including a non-discharge pulse not to discharge the liquid and a discharge pulse to discharge the liquid, the non-discharge pulse and the discharge pulse being serial in time in the drive waveform,
Td being in a range of Tc−0.2×Tc to Tc+0.45×Tc, and
Vp 1 being in a range of −10% to +10% of Vpp 1 ,
where Td represents a time interval between the non-discharge pulse and the discharge pulse, Tc represents a natural vibration period of a pressure chamber of the liquid discharge head, Vp 1 represents a peak value of the non-discharge pulse, and Vpp 1 represents a peak value of the non-discharge pulse at which a droplet speed of liquid discharged by the discharge pulse takes a local minimum value.