Abstract: The present invention relates to an image forming apparatus in which a sheet cassette for containing sheets is removably mounted to a body of the apparatus. The image forming apparatus comprises a frame structure having a pair of legs spaced apart from each other, a bottom plate arranged on the legs, a first side plate arranged at one ends of the legs and uprightly mounted on the bottom plate, a second side plate arranged in confronting relation to the first side plate at the other ends of the legs and having a lower end portion extending below the legs and covering the other ends of the legs, and stay members for interconnecting the first and second side plates at their upper portions.

Abstract: A sheet feeding device for use in an image forming apparatus provided with a sheet support plate and one or more rotary members for separating and feeding sheets. A recessed portion is formed on the sheet support plate in a position opposing to each rotary member. A detachable auxiliary member is provided to be fitted in the recess to form a plane coplanar with that of the sheet support plate. An engaging device can be provided, to engage with a step portion formed in a cassette housing portion of the apparatus to keep the cassette from being entirely removed from the housing. The engaging device may, for example, include an elastic part and an engaging part integrally molded with each other.

Abstract: An automatic original feeding apparatus has a coordinates position detecting device provided with a supporting table for supporting thereon a sheet original of which the area during image formation is to be designated, a conveying device for directing the inserted sheet original to a predetermined position, and a feed device provided upstream of the conveying device and responsive to the termination of the area designation to change over to a feeding position and feed the sheet original on the supporting table to the conveying device.

Abstract: A document feeding apparatus comprising a first original supporting device on which an original is placed, an original inlet port for receiving the original placed on the first original supporting device, a conveying device for guiding the original fed from the inlet port to a predetermined position and exhausting the original from the predetermined position, and a second original supporting device mounted on a housing of the document feeding apparatus and having an image area designation device for designating an image area of the original. In an image area designation mode of the apparatus, the original is placed on the image area designation device, a desired image area is designated, and the original is placed on the first original supporting device and is guided to the predetermined position through the inlet port.

Abstract: An image forming apparatus includes an image forming station for forming an image on a sheet; a rotatable member for transferring the sheet in a first direction toward the image forming station; supporting device for supporting the rotatable member for displacement in a second direction which crosses the first direction; driving device for displacing the rotatable member in the second direction to correct deviation of the sheet in the second direction; and inlet guide for guiding the sheet to the rotatable member, the guide being displaceable in the second direction together with the rotatable member.

Abstract: An image forming apparatus capable of reproducing in different colors a plurality of image areas selected from a plurality of different originals on a single copy sheet.

Abstract: An image forming apparatus includes an image forming station for conveying a sheet material along a lateral reference position and for forming an image on the sheet material; refeeding device for refeeding to the image forming station the sheet material on which the image has been formed in the image forming station; means, provided in the sheet refeeding means, for shifting the sheet material in the lateral direction from the lateral reference position by a predetermined amount, wherein the amount of the shift is predetermined on the basis of a change in a lateral dimension of the sheet material resulting from an image forming operation in the image station.

Abstract: An image forming apparatus capable of effecting plural image forming operations on one transfer sheet includes an image transfer device for transferring an image on the transfer sheet, an image magnification changing mechanism for changing the magnification of the image to be transferred onto the transfer sheet, and a control device for controlling the magnification changing mechanism in accordance with deformation of the transfer sheet caused by an image forming operation on the transfer sheet, after a first image is formed on the transfer sheet and before a second image is formed on the same transfer sheet, whereby those images are correctly registered.

Abstract: A sheet stacking device and an image forming apparatus provided with the sheet stacking device. The sheet stacking device has a sheet sorting function, and in addition, sheet re-feeding function so as to make it possible to produce a duplex copy or superimposed copy. It is further possible to use the sorter portion as a sheet feeding facility.

Abstract: An image forming apparatus such as a copying apparatus and a laser beam printer, is capable of forming a superimposed image or duplex image on one sheet. The sheet which has been once subjected to the image forming operation and which is going to be subjected to another image forming operation is reintroduced into the image forming station selectively through a flow-through sheet passage or through an intermediate tray on which the transfer sheets are once stacked. A displaceable flapper is provided to direct the sheet selectively to the flow-through passage or to the intermediate tray.

Abstract: An image forming apparatus includes a plurality of the developing devices for developing the latent image formed on an image bearing member. The plural developing devices are each movable between its developing position for developing the latent image on the image bearing member and its retracted position away from the image bearing member. The image forming apparatus includes a shutter for selectively opening and closing the developing aperture of the developing device of one of the developing devices. The shutter opens and closes the developing aperture of said one of the developing devices in association with movement of the other developing device between the developing position and the retracted position.