Abstract: The liquid ejection apparatus has: a liquid ejection head which includes a nozzle plate forming a nozzle surface in which nozzles ejecting droplets of a first liquid are provided; a wiping member which wipes the nozzle surface; an edge determination device which includes a determination plate with which a front tip portion of the wiping member wiping the nozzle surface can make contact, and determines an edge shape of the front tip portion of the wiping member according to a state of the determination plate; and a judgment device which judges timing of replacing the wiping member, according to the edge shape determined by the edge determination device.

Abstract: A fluid clutch comprises a driving disc rotationally driven by a driving section, a rotatable casing enhousing the driving disc, a blower attached to the casing, and an oil supply means for supplying an oil from an outside to a torque transmission gap between the driving disc and the casing. Further, a driving section may be connected by means of a flexible joint to either one of the casing or the disc. The fluid clutch can always attain optimum control by adjusting the amount of the oil at a high accuracy and rapidly depending on various kinds of operation conditions. A breezer also is provided for releasing gas from the torque transmission chamber when pressure exceeds a predetermined upper limit, and for enabling inflow of atmospheric air to the torque transmission chamber when pressure is less than a predetermined lower limit. The clutch is endurable to external vibrations.