Liquid ejection apparatus and method for cleaning liquid ejection apparatus

Abstract

A liquid ejection apparatus including a liquid ejection head having a nozzle, a cleaning mechanism that performs cleaning of the nozzle by drawing a liquid from inside the nozzle, and a controller that controls operation of the liquid ejection apparatus is provided. The controller includes a timer device that tracks time, a first memory section, a second memory section, a power supply, a determining section, and a tracked time correction section. The first memory section stores an end time at which a previous cycle of the cleaning has ended as end time information. The second memory section stores a tracked time tracked by the timer device as tracked time information. The power supply is charged when a power is supplied to the liquid ejection apparatus and supplies the charged power to the timer device when power supply to the liquid ejection apparatus is stopped. The determining section determines whether time tracking by the timer device is stopped. If determination of the determining section is positive when the power supply to the liquid ejection apparatus is resumed after having been stopped, the tracked time correcting section reads out the tracked time information from the second memory section and causes the timer device to start the time tracking from the time indicated by the tracked time information that was stored when power supply to the liquid ejection apparatus was stopped. If the controller determines that the difference between the tracked time tracked by the timer device and the end time indicated by the end time information stored in the first memory section is longer than or equal to a predetermined period, the controller operates the cleaning mechanism to carry out the cleaning.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

The invention, together with objects and advantages thereof, may best be understood by reference to the following description of the presently preferred embodiments together with the accompanying drawings in which:

FIG. 1 is a perspective view schematically showing an inkjet printer according to a first embodiment of the present invention;

FIG. 2 is a diagrammatic view showing a cleaning mechanism of the first embodiment;

FIG. 3 is a block diagram representing the electric configuration of the first embodiment;

FIG. 4 is a flowchart representing a routine of a power-off procedure of the first embodiment;

FIG. 5 is a flowchart representing a routine of a power-on procedure of the first embodiment;

FIG. 6 is a flowchart representing the routine of a timer cleaning procedure of the first embodiment;

FIG. 7 is a timing chart representing correction of tracked time of the first embodiment;

FIG. 8 is a flowchart representing the routine of a power-on procedure according to a second embodiment of the present invention;

FIG. 9 is a timing chart representing correction of tracked time of the second embodiment; and

FIG. 10 is a timing chart representing time tracking of a comparative art.

Claims

1. A liquid ejection apparatus including a liquid ejection head having a nozzle, a cleaning mechanism that performs cleaning of the nozzle by drawing a liquid from inside the nozzle, and a controller that controls operation of the liquid ejection apparatus, wherein the controller includes: a timer device that tracks time;a first memory section that stores an end time at which a previous cycle of the cleaning has ended as end time information;a second memory section that stores a tracked time tracked by the timer device as tracked time information;a power supply that is charged when a power is supplied to the liquid ejection apparatus and supplies the charged power to the timer device when power supply to the liquid ejection apparatus is stopped;a determining section that determines whether time tracking by the timer device is stopped; anda tracked time correcting section, wherein, if determination of the determining section is positive when the power supply to the liquid ejection apparatus is resumed after having been stopped, the tracked time correcting section reads out the tracked time information from the second memory section and causes the timer device to start the time tracking from the time indicated by the tracked time information that was stored when power supply to the liquid ejection apparatus was stopped;wherein, if the controller determines that the difference between the tracked time tracked by the timer device and the end time indicated by the end time information stored in the first memory section is longer than or equal to a predetermined period, the controller operates the cleaning mechanism to carry out the cleaning.

2. A liquid ejection apparatus including a liquid ejection head having a nozzle, a cleaning mechanism that performs cleaning of the nozzle by drawing a liquid from inside the nozzle, and a controller that controls operation of the liquid ejection apparatus, wherein the controller includes: a timer device that tracks time;a first memory section that stores an end time at which a previous cycle of the cleaning has ended as end time information;a second memory section that stores a tracked time tracked by the timer device as tracked time information;a power supply that is charged when a power is supplied to the liquid ejection apparatus and supplies the charged power to the timer device when power supply to the liquid ejection apparatus is stopped;a determining section that determines whether time tracking by the timer device is stopped; anda tracked time correcting section, wherein, if determination of the determining section is positive when the power supply to the liquid ejection apparatus is resumed after having been stopped, the tracked time correcting section reads out the tracked time information from the second memory section and causes the timer device to start the time tracking from the time determined by adding a predetermined correcting period to the time indicated by the tracked time information that was stored when power supply to the liquid ejection apparatus was stopped;wherein, if the difference between the tracked time tracked by the timer device and the end time indicated by the end time information stored in the first memory section is longer than or equal to a predetermined period, the controller operates the cleaning mechanism to carry out the cleaning.

3. The liquid ejection apparatus according to claim 2, wherein the correcting period is set in correspondence with a permitted amount of charge of the power supply.

4. The liquid ejection apparatus according to claim 1, wherein the power supply is a capacitor.

5. The liquid ejection apparatus according to claim 2, wherein the power supply is a capacitor.

6. A method for cleaning a liquid ejection apparatus, the liquid ejection apparatus having a liquid ejection head including a nozzle, cleaning being performed on the nozzle by drawing a liquid from inside the nozzle, wherein the method comprises: tracking time;storing an end time at which a previous cycle of the cleaning has ended as end time information;storing tracked time information of the tracked time;determining whether time tracking is stopped;causing, if the determining is positive when the power supply to the liquid ejection apparatus is resumed after having been stopped, a timer device to start the time tracking from the time indicated by the tracked time information that was stored when power supply to the liquid ejection apparatus was stopped; andperforming the cleaning if the difference between the tracked time and the end time indicated by the end time information is longer than or equal to a predetermined period.

7. A method for cleaning a liquid ejection apparatus, the liquid ejection apparatus having a liquid ejection head including a nozzle, cleaning being performed on the nozzle by drawing a liquid from inside the nozzle, wherein the method comprises: tracking time;storing an end time at which a previous cycle of the cleaning has ended as end time information;storing tracked time information of the tracked time tracked by a timer device;determining whether time tracking is stopped;causing, if the determining is positive when the power supply to the liquid ejection apparatus is resumed after having been stopped, the timer device to start the time tracking from the time determined by adding a predetermined correcting period to the time indicated by the tracked time information that was stored when power supply to the liquid ejection apparatus was stopped; andperforming the cleaning if the difference between the tracked time and the end time indicated by the end time information is longer than or equal to a predetermined period.

8. The method according to claim 7, wherein the correcting period is set in correspondence with a permitted amount of charge of the power supply.