Liquid ejection apparatus and control method therefor

A control method for a liquid ejection apparatus,

• the liquid ejection apparatus including:
• a liquid ejection head which has a nozzle and which is configured to eject a liquid from the nozzle;
• and
• a signal outputter configured to output an ejection state signal corresponding to an ejection state of the nozzle in a case that ejection driving for ejecting the liquid from the nozzle is performed in the liquid ejection head;
• the method comprising:
• causing the liquid ejection head to perform the ejection driving;
• and
• varying a process to be performed after the ejection driving between a case in which the ejection state signal outputted in a case that the ejection driving is performed is a first ejection state signal and a case in which the ejection state signal outputted in the case that the ejection driving is performed is a second ejection state signal, the first ejection state signal being a signal which fulfills a first condition regarding a maximum value and/or a minimum value of the ejection state signal in a first period and which does not fulfill a second condition regarding the maximum value and/or the minimum value of the ejection state signal in a second period after the first period;
• the second ejection state signal being a signal which does not fulfill the first condition in the first period and which fulfills the second condition in the second period.

A liquid ejection apparatus comprising:

• a liquid ejection head which has a nozzle and which is configured to eject a liquid from the nozzle;
• a signal outputter configured to output an ejection state signal corresponding to an ejection state of the nozzle in a case that ejection driving for ejecting the liquid from the nozzle is performed in the liquid ejection head;
• and
• a controller, wherein:
• the ejection state signal, outputted from the signal outputter, is a first ejection state signal or a second ejection state signal, depending on the ejection state of the nozzle, the first ejection state signal being a signal which fulfills a first condition regarding a maximum value and/or a minimum value of the ejection state signal in a first period and which does not fulfill a second condition regarding the maximum value and/or the minimum value of the ejection state signal in a second period after the first period;
• the second ejection state signal being a signal which does not fulfill the first condition in the first period and which fulfills the second condition in the second period;
• and
• the controller is configured to:
• cause the liquid ejection head to perform the ejection driving;
• determine whether the ejection state signal outputted in a case that the ejection driving is performed is the first ejection state signal or the second ejection state signal;
• and
• determine that the ejection state of the nozzle is a normal state in a case that the ejection state signal outputted in the case that the ejection driving is performed is determined to be the first ejection state signal, and that the ejection state of the nozzle is an abnormal state in a case that the ejection state signal outputted in the case that the ejection driving is performed is determined to be the second ejection state signal.