Patent ID: 8109599

Claim:
A liquid ejection apparatus, comprising: a liquid ejection head which includes a nozzle plate forming a nozzle surface in which nozzles ejecting droplets of a liquid are provided; a wiping member which wipes the nozzle surface; an edge determination device which includes: a determination plate having a determination plate surface with which a front tip portion of the wiping member wiping the nozzle surface can make contact, the determination plate surface and the nozzle surface being separate from each other; an imaging device which captures an image of a contact trace left on the determination plate surface, the contact trace being created when the front tip portion of the wiping member is brought into contact with the determination plate surface so that the liquid having been ejected from the liquid ejection head and having become attached to the front tip portion due to wiping the nozzle surface is deposited on the determination plate surface; and an image processing unit which processes the captured image of the contact trace, the edge determination device determining an edge shape of the front tip portion of the wiping member according to the image of the contact trace; a determination plate moving device which moves the determination plate upward and downward to adjust a height of the determination plate surface with respect to the nozzle surface; and a judgment device which judges timing of replacing the wiping member, according to the edge shape determined by the edge determination device, wherein the determination plate surface is placed higher than the nozzle surface by a distance that is larger than zero and smaller than an amount of overlap between the front tip portion of the wiping member and the nozzle plate surface.