Abstract: It is an object of the invention to provide a droplet ejection apparatus and a method of detecting and judging a head failure that can detect an ejection failure and carry out appropriate recovery processing according to a cause thereof.

Abstract: It is an object of the invention to provide a droplet ejection apparatus and a method of detecting and judging a head failure that can detect an ejection failure and carry out appropriate recovery processing according to a cause thereof.

Abstract: It is an object of the invention to provide a droplet ejection apparatus and a method of detecting and judging a head failure that can detect an ejection failure and carry out appropriate recovery processing according to a cause thereof.

Abstract: The invention provides an image forming apparatus that detects abnormality of a recording medium before the recording medium reaches an image recording section and prevents the recording medium having the abnormality from being fed to the image recording section. A recording medium fed from a sheet feeding section is conveyed to the image recording section by a conveying section, an image is formed on the recording medium, and then the recording medium is carried out. When a recording medium abnormality detecting section detects abnormality of the recording medium, which affects the image recording section, between the sheet feeding section and the image recording section, an abnormal discharge section discharges the recording medium via an abnormal time conveying path different from a normal conveying path. Alternatively, an abnormal stop section stops the conveyance of the recording medium before the image recording section.

Abstract: It is an object of the invention to provide a droplet ejection apparatus and a method of detecting and judging a head failure that can detect an ejection failure and carry out appropriate recovery processing according to a cause thereof.

Abstract: A centrifugal pump prevents a fluid from stagnating and so stops decreases in pump efficiency. An open impeller-type centrifugal pump includes pump vanes 12 that are connected via a vane boss 10 to an end part of a rotational shaft 8, a casing 14 that is connected to an end part of the pump base part 6 and forms a fluid chamber R surrounding the pump vanes 12, and an intake 16 and an outtake 18 that are formed in the casing 14. The pump vanes 12 are composed of pump vanes 12a to 12c that are integrally formed with current plates 20a to 20c. The current plates 20a to 20c cause some of the fluid that enters via the intake 16 to flow downwards along the axial direction of the rotational shaft 8. The fluid that flows along the current plates causes a centrifugal flow from an inner periphery to an outer periphery in a gap between a pump base part and the lower surfaces of the pump vanes.