Abstract: Disclosed is a sheet transport mechanism for use in an image forming apparatus provided with a sheet feed mechanism for feeding a sheet one by one, an imaging assembly for forming an image on the sheet, a fixing unit for fixing the image on the sheet, a discharge unit for discharging the sheet outside the apparatus, a main transport path extending from the sheet feed mechanism to the discharge unit, a sheet inverting path branched out from the main transport path at a position between the fixing unit and the discharge unit to turn the sheet upside down so as to feed the sheet toward the imaging assembly again, and sheet transport means disposed at a certain position of the main transport path and the sheet inverting path to transport the sheet in a certain direction. The sheet is held by more than one pair of the sheet transport means while guided along the sheet inverting path.

Abstract: A paper holder mounting mechanism for mounting a paper holder in an apparatus, the paper holder mounting mechanism includes a vertically-acting paper holder locking mechanism that is put to an interlocked state when the paper holder is inserted into the apparatus; a sliding guide device; and two joints disposed along the inserting direction of the paper holder for connecting the sliding guide device to one of side walls of the paper holder. The joints are set such that a rear portion of the paper holder is swingable up and down about the joint at the front to effect an interlocking action of the paper holder locking mechanism.

Abstract: Near a discharge device (48) for discharging paper (P) with an image formed thereon, there is provided a punch (7) for punching holes. The drive of the discharge device (48) is controlled so that the punch punches the punch holes in the trailing portion of the paper (P), without causing creasing or tearing or change in the quality of the paper (P). The punch (7) includes punching cutters (72) and a punching die (74). The punching cutters (72) and the punching die (74) are provided in a unit (U) which can be drawn out of a casing (1) covering the punch (7). With the unit (U) drawn out of the casing (1), jam recovery can be easily executed. The unit (U) is movable in the width direction of the paper (P), thereby making it possible to adjust the position of punched holes. A collecting box (76) for collecting paper scraps (P1) is disposed in the unit (U). If the collecting box (76) is pivoted or the opening (76a) thereof is lifted up when the unit (U) is pivoted, the paper scraps (P1) therein will not fall out.

Abstract: An image forming apparatus having a main body with an opening portion provided in one face of the main body, and a thermal transfer printer. The thermal transfer printer records desired information additively on paper on which a toner image has been fixed. The printer uses a thermal head to press an ink-ribbon on the paper. The thermal transfer printer includes a casing in which a cassette for housing the ink-ribbon is detachably mounted, a thermal head support for supporting the thermal head, and an interlocking mechanism. The interlocking mechanism retracts the thermal head with the thermal head support in response to retraction of the casing. Thus, it is possible to detach the cassette from the main body through the opening portion. This facilitates replacement of cassettes and clearing of paper jams.

Abstract: A latent electrostatic image developing device, including a cartridge loading section having an open top and a toner cartridge adapted to be removably loaded into the cartridge loading section. The cartridge loading section includes a pair of upwardly facing supporting shoulder surfaces extending longitudinally in laterally spaced-apart relationhsip, guiding side surfaces rising respectively from the outside edges of the shoulder surfaces, and a guiding rear surface extending between the rear ends of the guiding side surfaces. The guiding side surfaces respectively having holding protrusions provided at their front end portions. Engaging protrusions are provided behind of the holding protrusions at a predetermined distance therefrom. The toner cartridge includes a loading flange having side flange portions disposed in correspondence to the pair of shoulder surfaces and a closing member extending above the loading flange while surrounding both sides and the rear end thereof.

Abstract: A position controlling member for controlling the leading ends of paper sheets housed in a paper receiving member is provided at a free end thereof with an auxiliary double feed preventing member having large friction factor or force and engaging with a lower side of a paper sheet during return movement thereof to a position controlling position thereof, thereby preventing double feeding of paper sheets without interfering with the paper feeding operation.

Abstract: A shell-type electrostatic copying apparatus comprising a supporting structure consisting of a lower supporting frame and an upper supporting frame mounted on the lower supporting frame for free pivoting between an open position and a closed position about a first pivot axis as a center, an endless carrier member having a photosensitive material disposed on its peripheral surface, a developing device for developing a latent electrostatic image formed on the surface of the photosensitive material and a copying paper conveying mechanism.

Abstract: A paper feeding device includes conveyor rollers including top rollers and bottom rollers which rotate in the same direction and disposed respectively on two shafts in alternate positions. Timing rollers are provided on the down stream side of the conveyor rollers. The center-to-center distance between the two shafts is somewhat smaller than the sum of the radii of the top and bottom rollers. A recess is provided on each of the top rollers, so that the recess faces the direction of the circumference of the bottom rollers, when the forward end of the original sheet conveyed to the timing rollers by conveyor rollers abuts the timing rollers.

Abstract: A copying machine paper supply enables various paper supply cassettes having different volumes to be easily accommodated in only one large space. Cassette holding members are formed at opposite sides of the space and receive guide portions formed on opposite sides of each paper supply cassette. The cassette thus is housed in the space and is supported at the opposite sides thereof only.

Abstract: An electrostatic copying apparatus wherein a stationary original document image is projected onto a photosensitive member during movement of an optical device for exposing, and an electrostatic latent image formed on the photosensitive member is transferred onto a copy sheet and is fixed, comprising (a) a jam detecting means for immediately detecting a copy sheet being jammed on a transport path; and (b) a cleaning device for removing residual toner particles remaining on the photosensitive member by means of magnetic force and for storing the removed toner particles after transferring operation. According to this invention, an occurrence of jam is detected immediately, and thus a fault or an accident of the electrostatic copying apparatus due to jam is prevented from expanding.

Abstract: An electrostatic copying apparatus is provided wherein a stationary original document image is projected onto a photosensitive member during movement of an optical device for exposure. An electrostatic latent image formed on the photosensitive member is transferred onto a copy sheet and is fixed. A jam detecting means is provided for immediately detecting a copy sheet being jammed along a transport path. A cleaning device removes residual toner particles remaining on the photosensitive member by means of magnetic force and stores the removed toner particles after a transferring operation. The occurrence of a jam is detected immediately, and thus a fault or an accident of the electrostatic copying apparatus due to the jam is prevented from continuing.

Abstract: A copying apparatus includes a copy paper cutting device which is operated when an original document or an optical device for exposure reaches a predetermined position. The original document or the optical device is stopped when a trailing edge of a copy paper is detected. After at least the leading edge of the copy paper passes through the copy paper cutting device, the copy paper is fed out entirely from an apparatus frame without operating the copy paper cutting device. This results in that the last copy paper sheet of the roll of copy paper is not shorter than the distance between transport rollers in the copy paper passageway to prevent a copy paper jam.