Patent ID: 8246134

Claim:
An inkjet recording apparatus comprising: a recording head comprising a pressure generation section which is driven to cause a movement by application of a drive signal, a pressure chamber whose volume is expanded or contracted by the movement of the pressure generation section, and a nozzle connecting to the pressure chamber; and a drive signal generator, wherein by an applied drive signal to the pressure generation section, a volume of the pressure chamber is expanded or contracted to eject an ink droplet from the nozzle, wherein, the drive signal generator is configured to generate the drive signal including at least a first expansion pulse which expands the volume of the pressure chamber, a contraction pulse, which is applied successively to the first pulse, to contract the volume of the pressure chamber, and a second expansion pulse, which is applied successively to the contraction pulse, to expand the volume of the pressure chamber, wherein a total pressure PS caused by residual vibration of liquid in the pressure chamber with respect to time t is expressed by. PS=ΣPi ( i ) P ( i )= Vi ×Exp{−( t−ei )/τ}×Sin{2π× fr ×( t−ei )} where, τ represents a specific decay constant obtained from an ejection experiment, fr: 1/(2AL) AL: ½ of the acoustic resonance period of the pressure chamber, Vi: voltage change at an i-th edge of a drive waveform, P(i): pressure component generated by the i-th edge of the drive waveform ei: a time when i-th edge of the drive form is generated and, t represents a time; wherein, the drive signal generator is configured to generate the first expansion pulse, the contraction pulse and the second expansion pulse each having a prescribed pulse width and pulse voltage value such that the drive signal satisfies that: a position of a peak value P 1 of positive pressure is not more than 1.45AL from an applying start time of the first expansion pulse, and | M 1/ P 1|≧0.45, where M 1 is a first peak value of negative pressure in the pressure chamber caused by the first expansion pulse, P 1 is a peak value of a positive pressure succeeding to the first negative peak value M 1 , and M 2 is a peak value of a negative pressure succeeding to the positive peak value P 1 .