Roland Dg Corporation

Mitsubishi Heavy Industries Limited

Japan Ship Machinery & Equipment Association

Oshima Shipbuilding Co., Ltd.

Keisuke Misawa

Takahiro Nakagawa

Kenji Kawagoe

Takashi Makinose

Kenji Kazaoka

Shoichi Kitamura

Shinji Nonaka

Naohiro Hiraoka

A driving signal generation circuit generates a main driving signal including, in each of driving periods, at least a first sub driving signal including a first driving pulse and a second driving pulse, and a second sub driving signal including a third driving pulse and provided before the first sub driving signal. A driving signal supply circuit includes a first dot generator supplying the first sub driving signal but not supplying the second sub driving signal to an actuator coupled with a vibration plate defining a portion of a pressure chamber, and a second dot generator supplying the first sub driving signal and the second sub driving signal to the actuator.

Liquid ejection device and inkjet printer including the same

A liquid injection device includes a liquid injection head and a controller including a driving signal generator generating a driving signal including, in one liquid drop injection period, a first driving pulse and a second driving pulse, and a driving signal supplier. The first driving pulse maintains the pressure chamber in an expanded state for a time period of about (&#xbd;)&#xd7;Tc; and the second driving pulse starts at a timing that is about n&#xd7;Tc after the start of the first driving pulse, n being an integer satisfying n&#x2265;2, to maintain the pressure chamber in the expanded state for the time period of about (&#xbd;)&#xd7;Tc, and to inject the second liquid drop at a speed higher than, or equal to, a speed at which the first liquid drop is injected.

Liquid ejection device and inkjet recording including the same

A driving signal generating circuit generates, for each driving period, a main driving signal including a first sub driving signal including a first driving pulse, a second sub driving signal including a second driving pulse, and a third sub driving signal including a third driving pulse. The third sub driving signal follows the second sub driving signal. A driving signal supplying circuit includes a second dot former to supply the second sub driving signal and the third sub driving signal to an actuator coupled to a defining plate defining a portion of a pressure chamber, without supplying the first sub driving signal to the actuator. The third driving pulse starts after a lapse of a preset time from the start of the second driving pulse. The preset time is equal to a value of about p&#xd7;Tc, where p is greater than 2.

Liquid discharge device and inkjet printer including the same

A liquid injection device includes a driving circuit supplying, to an actuator, a driving signal including a prior driving pulse and a subsequent driving pulse supplied after the prior driving pulse. Where a speed of a leading tip of a prior liquid pillar injected from the nozzle by the prior driving pulse is V, a speed of a leading tip of a subsequent liquid pillar injected from the nozzle by the subsequent driving pulse is V, a time period from start of the injection of the prior liquid pillar until start of the injection of the subsequent liquid pillar is t, a difference between a time period from the injection of the prior liquid pillar from the nozzle until division of the prior liquid pillar in the case where the prior driving pulse is supplied to the actuator but the subsequent driving pulse is not supplied to the actuator, and the time period t, is t, and a time period from start of the injection of the prior liquid pillar until separation of the prior liquid pillar from the nozzle in the case where the prior driving pulse is supplied to the actuator but the subsequent driving pulse is not supplied to the actuator is t, t&#x2264;tand V&#x2265;V&#xd7;(t/t+1) are satisfied.

Liquid injection device and inkjet printer including the same

A liquid injection device includes a driving signal correction circuit correcting a reference driving signal based on a temperature detected by a temperature sensor. The driving signal correction circuit includes a first correction circuit that corrects injection pulses excluding a liquid drop injection speed-controlling injection pulse when the temperature detected by the temperature sensor is lower than or equal to a predetermined reference temperature, and a second correction circuit that corrects all of the injection pulses when the temperature detected by the temperature sensor is higher than the predetermined reference temperature.

Liquid injection device and inkjet recording device including the same

A liquid injection device includes a liquid injection head and a controller that generates a driving signal including first through fourth driving pulses in one liquid drop injection period and supplies the driving signal to the liquid injection head. The discharge time period of each of the first and second driving pulses is preferably set to about (&#xbd;)&#xd7;Tc. The start timing of the second driving pulse is preferably set to about m&#xd7;Tc (m&#x2267;1) after the start of the first driving pulse. The second ink drop is preferably set to be injected at a speed of the first ink drop or higher. The start timing of the third driving pulse is preferably set to about (n+(&#xbd;))&#xd7;Tc (n&#x2267;1) after the start of the second driving pulse. The start timing of the fourth driving pulse is preferably set to about p&#xd7;Tc (p&#x2267;2) after the start of the third driving pulse. The fourth ink drop is injected at a speed of the third ink drop or higher.

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Hamamatsu, Japan

Keisuke Misawa