Ink jet recording head drive device and method thereof
AssigneeNEC Corporation
InventorToyoji Ushioda
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Abstract
An ink jet recording head according to the present invention ejects an ink droplet from a nozzle by applying a drive voltage to an electro-mechanical transducer located at the position corresponding to a pressure generation chamber, and deforming the electro-mechanical transducer. In the voltage wave form of the drive voltage that the ink jet recording head applies to the electro-mechanical transducer during a recording time, the rise time up to the peak voltage, and the fall time down to the basic voltage are both equal to approximately a half of the natural period To of the acoustic oscillation of the ink in an ink-flow course system, whereas the time Tw from the beginning of rising to the beginning of falling is equal to integer-times the natural period To including one.
Claims18
A drive apparatus of an ink jet recording head which includes at least one ink-flow course system, comprised of a nozzle and a pressure generation chamber, and also connected to an ink pool, and which deforms an electro-mechanical transducer to eject an ink droplet from the nozzle during a recording time by applying a drive voltage to the electro-mechanical transducer located at the position corresponding to the pressure generation chamber, comprising:
- a hold circuit for holding a voltage applied to said electro-mechanical transducer;
- a charge circuit for increasing said voltage from the basic value up to the peak value in a rise time,
- a discharge circuit for decreasing said voltage from the peak value down to the basic value in a fall time;
- a control circuit for controlling said charge circuit and discharge circuit to form a voltage wave form for driving said electro-mechanical transducer, in accordance with a natural period of a harmonic wave of an order number to be oscillated in ink deposited in the ink-flow course system,
- wherein said control circuit comprises:
- means for determining an order number of said harmonic wave to be oscillated in said ink-flow course system;
- and
- means for setting said rise time and fall time both approximately equal to a half of a natural period of a harmonic wave of said order number.
An ink jet recording head drive method of allowing a nozzle to eject an ink droplet during a recording time by applying a drive voltage and thereby deforming an electro-mechanical transducer, where the electro-mechanical transducer is located at the location corresponding to a pressure generation chamber, and at least one ink-flow course system comprised of the nozzle and the pressure generation chamber is connected to an ink pool;
- wherein the drive method comprises the steps of:
- generating a drive voltage with a voltage wave form corresponding to a natural period of a harmonic wave of an order number to be oscillated in ink in the ink-flow course system;
- and
- applying the drive voltage generated to the electro-mechanical transducer,
- wherein said step of generating a drive voltage comprises the steps of:
- determining an order number of a harmonic wave to be oscillated in said ink-flow course system;
- and
- increasing said drive voltage in a rise time defined as a time from a basic value to a peak value, and decreasing said drive voltage in a fall time defined as a time from said peak value to said basic value, in a time approximately equal to a half of a natural period of a harmonic wave of said order number.
Dependencies are inferred from the claim text.