Abstract: An image forming apparatus includes an original document conveying device to convey an original document at a predetermined conveying speed according to a magnification ratio. An original document reading device reads image information of the original document with a one-dimensional image sensor, and an information omission device omits information of the image information of the original document read by the original document reading device. An image forming device forms an image according to the image information read by the original document reading device synchronized with conveying of the original document by the original document conveying device.

Abstract: A device installed in an imsge recording apparatus for pulling out the leading edge of a rolled recording medium such as a rolled paper and then cutting the recording medium at a predetermined length as measured from the leading edge to feed the resulting sheet to a predetermined recording section of the apparatus. A plurality of paper feed mechanisms are each provided with a cutter for cutting a paper which is paid out from a roll. When two or more of the paper feed mechanisms are loaded with a paper of a desired kind, they are automatically and repetitively switched from one to another every time a sheet feed operation is performed.

Abstract: A device installed in a copier, facsimile apparatus or similar image forming apparatus of the type including a fixing unit displays a waiting time necessary for the warm-up of the apparatus. The device calculates an elevation rate of fixing temperature within a predetermined time interval, produces a difference between a current temperature of the fixing unit and a set fixing temperature on the basis of the elevation rate, and thereby determines a waiting time. Further, the waiting time is determined on the basis of a temperature inside the apparatus when the ambient temperature is comparatively low and on the basis of a temperature of the fixing unit when it is higher than a predetermined level.

Abstract: A device applicable to an image recording apparatus for feeding a recording medium in the form of a paper roll or a cut paper to a predetermined recording section of the apparatus. The device includes a plurality of paper feed mechanisms for feeding a recording medium. A sensor responsive to the kind of a recording medium in the form of a roll and a sensor responsive to the amount of remaining recording medium are associated with each of the paper feed mechanisms. When two or more paper feed mechanisms are each loaded with a recording medium of a desired kind, one of them which has a larger amount of recording medium remaining therein is automatically selected. When the amount of recording medium remaining in the feed mechanism being selected becomes substantially zero, another feed mechanism which is also loaded with a recording medium of the specified kind is automatically selected in place of the feed mechanism which has been exhausted.

Abstract: The surface of an electrostatic drum (12) is charged and radiated with a light image of an original document (16) to form an electrostatic image which is developed to form a toner image. A copy sheet (18) is moved into engagement with the drum (12) and an electrostatic charge applied thereto to transfer the toner image to the copy sheet (18). A corona discharge unit (27) applies an alternating voltage to the leading edge of the copy sheet (18) to discharge the same and cause the leading edge to separate from the drum (12). Thereafter, the discharge unit (27) applies an asymmetrical alternating voltage which partially discharges the remaining portion of the copy sheet (18) but does not cause the same to separate from the drum (12).