Abstract: The present invention provides a sheet post-treatment apparatus for receiving a sheet material on which an image was formed by an image forming apparatus and for post-treating such sheet material and for sending the sheet material to a next post-treatment apparatus. A sheet receiving opening has the same height as a sheet sending opening.

Abstract: The present invention provides an automatic original feed apparatus comprising an original stacking portion on which a plurality of originals can be rested, an introduction path for directing the original supplied from the original stacking portion to a reading portion, an annular reverse rotation path for reversely rotating the original discharged from the reading position and for directing the original to the reading position again, a discharge path for discharging the original discharged from the reading position onto a discharge portion, and original feed rotary members arranged in the introduction path, reverse rotation path and discharge path, respectively, and rotated in one direction.

Abstract: Disclosed is an image heating device for a fixing device in image forming apparatus. The image heating device is provided with two heaters and an image fixing roller. The image fixing roller is heated by the two heaters, one having the heat distribution in the center and the other having the heat distribution in the end portion of the fixing roller. The heaters are alternately energized so that the power requirement is maintained limited. The energization time ratio of the heaters is suitably varied according to the sheet size in order to compensate the temperature loss in the end portions when the heating is conducted in the central portion only, or to reduce the temperature rise in the end portions, encountered when narrow sheets are consecutively passed, thereby preventing various drawbacks resulting from uneven temperature distribution on the fixing roller.

Abstract: The present invention provides a sheet post-treatment apparatus in which a tab sheet is used to sort sheet materials, comprising a tab trimmer for successively cutting each of plural tab forming sheet materials being supplied, to form tabs in the sheet materials at offset tab positions. The tab trimmer is in modular form which can be removed from the apparatus and replaced with another modular tab trimmer.

Abstract: An image fixing apparatus includes a rotatable member for being heated by a heating source to fix an image on an image supporting member, first and second detecting elements responsive to temperature of the rotatable member, and wherein the first and second detecting elements are disposed on substantially the same circumferential line of the rotatable member.

Abstract: A driving mechanism for driving an electrophotographic photosensitive body operates through a torque limiter. The torque limiter is arranged on a support shaft for supporting the photosensitive body. A driving gear for driving a developing member is arranged coaxially with the torque limiter independently of the latter. This arrangement reduces the load applied to the torque limiter. In addition, the mechanism remains compact.

Abstract: An original scanning apparatus comrpises a scanning unit for scanning an original. The scanning unit has a mirror and a light source for illuminating the original. A connecting member is electrically connected to the scanning unit. A guide member supports and guides one end of the scanning unit. The guide member fixes a position of the one end of the scanning unit in a vertical direction. At least a part of a driving element is disposed at the position overlapping with the guide member in the vertical direction, but not overlapping with the mirror of the scanning unit. The connecting member is provided at the side of the guide member.

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 image forming apparatus includes an image bearing member, image forming station for forming a latent image on the image bearing member, a conveying passage extending toward the image bearing member to guide a developing device, a first moving mechanism for engaging with the developing device in the conveying passage and moving it in a substantially horizontal plane, wherein the image bearing member, the latent image forming station, the conveying passage and the first moving mechanism are provided in a main body of the image forming apparatus, a device for accommodating a plurality of developing devices.