Quantcast

Ink jet recording apparatus and method for driving ink jet recording head incorporated in the apparatus

Imported: 24 Feb '17 | Published: 06 Jan '04

Satoru Hosono, Kenji Otokita

USPTO - Utility Patents

Abstract

A recording head includes a nozzle orifice, a pressure chamber communicated with the nozzle orifice, and an actuator which varies a volume of the pressure chamber. A drive signal generator generates a drive signal in which a plurality of drive pulses are arranged within a unit recording period. The drive pulses includes at least a first drive pulse composed of an expanding element, which drives the actuator so as to expand the pressure chamber, an expansion holding element, which drives the actuator such that the expanded state of the pressure chamber is held in a first time period roughly equal to a first natural vibration period which is a natural vibration period of ink stored in the pressure chamber, and an ejecting element, which drives the actuator so as to contract the pressure chamber so that the ink in the pressure chamber is ejected from the nozzle orifice.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

The above objects and advantages of the present invention will become more apparent by showing in detail preferred exemplary embodiments thereof with reference to the accompanying drawings, wherein like reference numerals designate like or corresponding parts throughout the several views, and wherein:

FIG. 1 is a perspective view showing a structure of an ink jet printer according to the present invention;

FIG. 2 is a block diagram showing an electrical configuration of a printer;

FIG. 3 is a sectional view showing a construction of a recording head;

FIG. 4 is a diagram showing a drive signal;

FIG. 5 is a chart showing a relation between driving voltage for discharging the designated quantity of ink drops and jetting speed of ink drops, and supplying time of a fourth holding element in the drive signal;

FIGS. 6A to

6G are model figures showing variation of meniscus with time when an ink drop is ejected;

FIG. 7 is a chart showing a relation between crosstalk and supplying time of the fourth holding element; and

FIG. 8 is a table showing a relation between pulses in the drive signal and recorded gradation levels.

Claims

1. An ink jet recording apparatus, comprising:

2. The recording apparatus as set forth in claim 1, wherein a third time period in which the ejecting element is supplied is roughly equal to a second natural vibration period which is a natural vibration period of the actuator.

3. The recording apparatus as set forth in claim 1, wherein each of the first time period and the second time period is set in a range of 80 to 120% of the first natural vibration period.

4. The recording apparatus as set forth in claim 1, wherein the selected drive pulse is determined in accordance with quantity of ink ejected from the nozzle orifice.

5. The recording apparatus as set forth in claim 4, wherein the drive signal includes at least the first drive pulse which drives the actuator so as to eject first amount of ink and a second drive pulse which drives the actuator so as to eject second amount of ink which is different from the first ink amount.

6. The recording apparatus as set forth in claim 5, wherein the second ink amount is less than the first ink amount.

7. The recording apparatus as set forth in claim 5, wherein the second drive pulse is arranged prior to the first drive pulse in the drive signal.

8. The recording apparatus as set forth in claim 4, wherein all the drive pulses in the drive signal are the first drive pulse.

9. A method of driving a recording head which includes a nozzle orifice, a pressure chamber communicated with the nozzle orifice, and an actuator associated with the pressure chamber, comprising the steps of:

10. The driving method as set forth in claim 9, wherein a time period in which the waiting step is performed is roughly equal to a natural vibration period of ink stored in the pressure chamber.

11. A method of driving a recording head which includes a nozzle orifice, a pressure chamber communicated with the nozzle orifice, and an actuator associated with the pressure chamber, comprising the steps of: