Control apparatus for a liquid ejecting head, liquid ejecting apparatus, and control method for a liquid ejecting head

1. A control apparatus for a liquid ejecting head, the liquid ejecting head including nozzle rows in which nozzles that eject a liquid from two or more liquid holding units that hold the same liquid are arranged in rows and an ejection unit that causes the liquid to be ejected through the nozzles, and the control apparatus for the liquid ejecting head causing the liquid to be ejected through the nozzles by driving the liquid ejecting head based on a liquid ejection command when the liquid ejection command has been inputted, the control apparatus comprising:

an input section that obtains a threshold passed signal outputted from a threshold sensor that detects the actual remaining liquid amount in the liquid holding unit, the threshold passed signal indicates that a threshold for a remaining liquid amount has been passed,

wherein when the threshold passed signal is inputted from the threshold sensor to the input section while the liquid ejection command is being executed, the control apparatus drives the liquid ejecting head so that the liquid continues to be ejected based on the liquid ejection command until the inputted liquid ejection command ends;

a remaining liquid amount estimation unit that estimates a remaining liquid amount that is the remaining amount of liquid held in each of the liquid holding units,

wherein in the case where the threshold passed signal has been inputted from at least one of the two or more liquid holding units after the ejection unit has been driven until the inputted liquid ejection command ends, the control apparatus determines whether or not the difference between the remaining liquid amounts estimated by the remaining liquid amount estimation unit from the remaining liquid amount estimation unit is greater than a predetermined value;

in the case where the difference between the remaining liquid amounts estimated by the remaining liquid amount estimation unit from the remaining liquid amount estimation unit is greater than the predetermined value, when the next liquid ejection command is executed, the control apparatus carries out control so that the liquid is ejected only through the nozzle rows to which the liquid is supplied from the liquid holding unit that has the greater remaining amount of liquid; and

in the case where the difference between the remaining liquid amounts estimated by the remaining liquid amount estimation unit from the remaining liquid amount estimation unit is less than the predetermined value, when the next liquid ejection command is executed, the control apparatus carries out control so that the liquid ejection amount of the nozzle rows to which the liquid is supplied from the liquid holding unit having a higher remaining amount is greater than the liquid ejection amount of the nozzle rows to which the liquid is supplied from the liquid holding unit having a lower remaining amount.

2. The control apparatus for a liquid ejecting head according to claim 1 ,

wherein in the case where the threshold passed signal has been inputted from all of the two or more liquid holding units after the ejection unit has been driven until the inputted liquid ejection command ends, the control apparatus makes a notification prompting all of the two or more liquid holding units to be replaced; and

in the case where the threshold passed signal has been inputted from one of the two or more liquid holding units, when the next liquid ejection command is executed, the control apparatus drives the ejection unit so that the ejection amount of the nozzle row to which the liquid is supplied from the liquid holding unit whose threshold sensor outputted the threshold passed signal becomes less than the ejection amounts of the other nozzle rows.

3. The control apparatus for a liquid ejecting head according to claim 1 ,

wherein the control apparatus carries out a notification prompting the liquid holding unit, of the two or more liquid holding units, that is provided with the threshold sensor from which the threshold passed signal has been inputted to be replaced after the ejection unit has been driven until the inputted liquid ejection command ends.

4. The control apparatus for a liquid ejecting head according to claim 1 ,

wherein the nozzle rows are configured of first and second nozzle rows whose respective nozzles are in the same position in a nozzle row direction and third and fourth nozzle rows whose nozzle positions are skewed from each other in the nozzle row direction; and

the first nozzle row and the third nozzle row are connected to a first liquid holding unit, and the second nozzle row and the fourth nozzle row are connected to a second liquid holding unit.

5. A liquid ejecting apparatus comprising:

a liquid ejecting head including nozzle rows in which nozzles that eject a liquid from two or more liquid holding units that hold the same liquid are arranged in rows and an ejection unit that causes the liquid to be ejected through the nozzles;

a control unit that causes the liquid to be ejected through the nozzles by driving the liquid ejecting head based on a liquid ejection command when the liquid ejection command has been inputted;

threshold sensors that detect the actual remaining liquid amount in respective liquid holding units and input threshold passed signals indicating that the remaining liquid amounts have exceeded a threshold to the control unit,

wherein when the threshold passed signal is inputted from the threshold sensor during the execution of the liquid ejection command, the control unit drives the liquid ejecting head so as to continue ejecting the liquid based on the inputted liquid ejection command until the liquid ejection command ends; and

a remaining liquid amount estimation unit that estimates a remaining liquid amount that is the remaining amount of liquid held in each of the liquid holding units,

wherein in the case where the threshold passed signal has been inputted from at least one of the two or more liquid holding units after the ejection unit has been driven until the inputted liquid ejection command ends, the control apparatus determines whether or not the difference between the remaining liquid amounts estimated by the remaining liquid amount estimation unit from the remaining liquid amount estimation unit is greater than a predetermined value;

in the case where the difference between the remaining liquid amounts estimated by the remaining liquid amount estimation unit from the remaining liquid amount estimation unit is greater than the predetermined value, when the next liquid ejection command is executed, the control apparatus carries out control so that the liquid is ejected only through the nozzle rows to which the liquid is supplied from the liquid holding unit that has the greater remaining amount of liquid; and

in the case where the difference between the remaining liquid amounts estimated by the remaining liquid amount estimation unit from the remaining liquid amount estimation unit is less than the predetermined value, when the next liquid ejection command is executed, the control apparatus carries out control so that the liquid ejection amount of the nozzle rows to which the liquid is supplied from the liquid holding unit having a higher remaining amount is greater than the liquid ejection amount of the nozzle rows to which the liquid is supplied from the liquid holding unit having a lower remaining amount.

6. The liquid ejecting apparatus of claim 5 , wherein the nozzle rows are configured of first and second nozzle rows whose respective nozzles are in the same position in a nozzle row direction and third and fourth nozzle rows whose nozzle positions are skewed from each other in the nozzle row direction; and

the first nozzle row and the third nozzle row are connected to a first liquid holding unit, and the second nozzle row and the fourth nozzle row are connected to a second liquid holding unit.

7. A liquid ejecting apparatus comprising:

a liquid ejecting head including nozzle rows in which nozzles that eject a liquid from two or more liquid holding units that hold the same liquid are arranged in rows and an ejection unit that causes the liquid to be ejected through the nozzles;

a control unit that causes the liquid to be ejected through the nozzles by driving the liquid ejecting head based on a liquid ejection command when the liquid ejection command has been inputted,

a threshold sensor that detects the actual remaining liquid amount in the liquid holding unit,

wherein when a threshold passed signal indicating that a threshold for a remaining liquid amount has been passed is inputted from the threshold sensor when the liquid ejection command is being executed, the control apparatus drives the liquid ejecting head so that the liquid continues to be ejected based on the liquid ejection command until the inputted liquid ejection command ends; and

a remaining liquid amount estimation unit that estimates a remaining liquid amount that is the remaining amount of liquid held in each of the liquid holding units,

wherein in the case where the threshold passed signal has been inputted from at least one of the two or more liquid holding units after the ejection unit has been driven until the inputted liquid ejection command ends, the control apparatus determines whether or not the difference between the remaining liquid amounts estimated by the remaining liquid amount estimation unit from the remaining liquid amount estimation unit is greater than a predetermined value;

in the case where the difference between the remaining liquid amounts estimated by the remaining liquid amount estimation unit from the remaining liquid amount estimation unit is greater than the predetermined value, when the next liquid ejection command is executed, the control apparatus carries out control so that the liquid is ejected only through the nozzle rows to which the liquid is supplied from the liquid holding unit that has the greater remaining amount of liquid; and

in the case where the difference between the remaining liquid amounts estimated by the remaining liquid amount estimation unit from the remaining liquid amount estimation unit is less than the predetermined value, when the next liquid ejection command is executed, the control apparatus carries out control so that the liquid ejection amount of the nozzle rows to which the liquid is supplied from the liquid holding unit having a higher remaining amount is greater than the liquid ejection amount of the nozzle rows to which the liquid is supplied from the liquid holding unit having a lower remaining amount.

8. The liquid ejecting apparatus of claim 7 , wherein the nozzle rows are configured of first and second nozzle rows whose respective nozzles are in the same position in a nozzle row direction and third and fourth nozzle rows whose nozzle positions are skewed from each other in the nozzle row direction; and

the first nozzle row and the third nozzle row are connected to a first liquid holding unit, and the second nozzle row and the fourth nozzle row are connected to a second liquid holding unit.

9. A control method for a liquid ejecting head including nozzle rows in which nozzles that eject a liquid from two or more liquid holding units that hold the same liquid are arranged in rows and an ejection unit that causes the liquid to be ejected through the nozzles, the control method causing the liquid to be ejected through the nozzles by driving the liquid ejecting head based on a liquid ejection command when the liquid ejection command has been inputted,

wherein when a threshold sensor that inputs a threshold passed signal in the case where the threshold sensor has detected that the remaining amount of liquid held in a corresponding liquid holding unit has exceeded a threshold has inputted the threshold passed signal during the execution of the liquid ejection command, the liquid ejecting head is driven so that the liquid continues to be ejected based on the liquid ejection command until the inputted liquid ejection command ends; and

estimating, by a remaining liquid amount estimation unit, a remaining liquid amount that is the remaining amount of liquid held in each of the liquid holding units,

wherein in the case where the threshold passed signal has been inputted from at least one of the two or more liquid holding units after the ejection unit has been driven until the inputted liquid ejection command ends, the control apparatus determines whether or not the difference between the remaining liquid amounts estimated by the remaining liquid amount estimation unit from the remaining liquid amount estimation unit is greater than a predetermined value;

in the case where the difference between the remaining liquid amounts estimated by the remaining liquid amount estimation unit from the remaining liquid amount estimation unit is greater than the predetermined value, when the next liquid ejection command is executed, the control apparatus carries out control so that the liquid is ejected only through the nozzle rows to which the liquid is supplied from the liquid holding unit that has the greater remaining amount of liquid; and

in the case where the difference between the remaining liquid amounts estimated by the remaining liquid amount estimation unit from the remaining liquid amount estimation unit is less than the predetermined value, when the next liquid ejection command is executed, the control apparatus carries out control so that the liquid ejection amount of the nozzle rows to which the liquid is supplied from the liquid holding unit having a higher remaining amount is greater than the liquid ejection amount of the nozzle rows to which the liquid is supplied from the liquid holding unit having a lower remaining amount.

10. The control method of claim 9 , wherein the nozzle rows are configured of first and second nozzle rows whose respective nozzles are in the same position in a nozzle row direction and third and fourth nozzle rows whose nozzle positions are skewed from each other in the nozzle row direction; and

the first nozzle row and the third nozzle row are connected to a first liquid holding unit, and the second nozzle row and the fourth nozzle row are connected to a second liquid holding unit.