Abstract: An imaging unit includes a developer unit which is supported rotatably about a predetermined rotation axis thereof by means of a drum unit. Spacing regulation sleeves are respectively fitted around opposite ends of a support shaft of a developer roller for regulating a spacing between the photoreceptor drum and the developer roller. A driven gear is engaged with one end of the support shaft of the developer roller for integral rotation thereof, and adapted to be driven by a drive transmission gear. By utilizing a driving force applied to the driven gear, the developer unit is biased about the rotation axis to press one spacing regulation sleeve fitted around one end of the support shaft of the developer roller against the photoreceptor drum. The other spacing regulation sleeve fitted around the other end of the support shaft of the developer roller is resiliently pressed against the photoreceptor drum by means of a resilient member.

Abstract: An electrostatic latent image developing device equipped with a developing housing, a developing roller rotatably disposed between the two side walls of the developing housing, and a feeding roller rotatably disposed between the two side walls of the developing housing neighboring the developing roller. A first bearing member is mounted on one side wall and has two bearings for supporting the ends of the rotary shafts of the developing roller and the feeding roller. A second bearing member is mounted on the other side wall and has a bearing for supporting the opposite end of either the rotary shaft of the developing roller or the feeding roller. A third bearing member is mounted on the other side wall and has a bearing for bearing support of the opposite end of the rotary shaft of the developing roller or the feeding roller not supported in bearing fashion by the second bearing member.

Abstract: An electrophotographic type image forming apparatus is provided with a base frame for supporting an image forming unit and an optical unit frame located above the base frame for supporting an optical unit, the optical unit frame having an extension portion positioned above the discharge tray. The apparatus is further provided with a reinforcing member attached to the optical unit frame. The reinforcing member has an attachment portion extending in a horizontal direction for reinforcing the extension portion of the optical unit frame, and a restricting portion extending in a vertical direction and having a lower end operable to come into contact with a specified portion of the base frame when the optical unit frame is subjected to an excessive load. The optical unit frame is prevented from deformation because the lower end of the restricting portion comes into contact with the base frame when an excessive load is applied to the optical unit frame, which assures high quality image formation.

Abstract: A toner replenishing device including a mounting base having a toner replenishment opening formed for replenishing a hopper with a toner, and a toner cartridge to be mountable on the mounting base at a replenishing position at which the toner can be replenished through the toner replenishment opening. The mounting base is provided with a replenishment opening shutter member, and locking means for inhibiting the turning of the replenishment opening shutter member. When the toner cartridge is mounted at the replenishing position, locking of the locking means is released, and when the container is turned, a through-hole of the toner cartridge and the toner replenishment opening open.

Abstract: A charging device is provided which is suitable for use in a compact electrophotographic image forming apparatus. The charging device includes: a pair of support members spaced a predetermined distance; and a discharge wire stretched between the pair of support members with one end thereof being fixed to one of the support members and with a middle portion thereof being supported by the other support member. One end of a coil spring is connected to the other end of the discharge wire, and the other end of the coil spring is received by a hooking portion of an electrode. The electrode is fixed in the vicinity of one of the support members.

Abstract: A toner cartridge for an image forming apparatus includes a toner storing unit having two flexible stirring rods disposed therein. Two tapered bearing portions disposed on a first side wall of the toner storage unit extend partially into the first side wall without piercing the first side wall, and two bearing portions on a second side wall extend completely through the second side wall. First ends of each of the stirring rods is tapered and fits into the tapered bearing portions on the first side wall of the toner storage unit. Second ends of the stirring rods extend through the bearing portions of the second side wall of the toner storage unit. Flange members are disposed on the second ends of the stirring rods, and a seal is interposed between each flange member and the second side wall. In another embodiment of the present invention, two of the bearing portions on the first side wall are generally square, and the first ends of the stirring rods have a generally spherical tip.

Abstract: In accordance with the present invention, there is provided a phenanthrylenediamine derivative represented by the general formula (1). The derivative is excellent in the electric charge transferring capability, the compatibility with a binding resin and the stability, thereby providing a photosensitive material which is highly sensitive and excellent in the durability. ##STR1## ?wherein R.sup.1, R.sup.2, R.sup.3 and R.sup.4 each represent a halogen atom, an alkyl group, an alkoxy group or an aryl group; and a, b, c and d each represent an integer from 0 to 5!.

Abstract: An electrostatic copying machine made up of an image-forming unit including a rotary drum having an exposure zone and a transfer zone, an optical system for projecting the image of the document to be copied onto the exposure zone, a copying paper-feeding system including a paper-feeding cassette that can be freely drawn to the front surface of the body of the copying machine, and a copying paper conveying passage for conveying a copying paper fed from the copying paper-feeding means through the transfer zone. A fixing device and a pair of paper-discharging rollers are disposed on the downstream side of the transfer zone. The paper-feeding cassette, image-forming unit, fixing device and the pair of paper-discharging rollers are successively arranged from one side toward the other side in the body of the copying machine within the maximum exposure scanning length of the optical system, and the copying paper conveying passage is arranged substantially linearly.

Abstract: A toner cartridge includes a container having a toner discharge opening formed therein, and an external member combined with the container so as to be relatively movable between a closed position at which the external member closes the toner discharge opening and an open position at which the external member uncovers the toner discharge opening. A compressible seal member extending along the peripheral edge of the toner discharge opening is disposed on the outer surface of the container. The seal member is compressed between the outer surface of the container and the inner surface of the external member. The seal member has a surface layer of cloth. A toner leakage preventing tape is stuck to a required site of the inner surface of the external member. The surface of the toner leakage preventing tape is non-adherent and has a coefficient of static friction .mu..sub.0, against the surface of a glazing, of 3.5 to 4.5, preferably 3.8 to 4.2.

Abstract: A synthetic resin cover having a grip is mounted on the upper surface of an upper case board that constitutes part of the fixing housing and covers the upper side of the fixing roller of an image forming machine. The cover has a cover body and attaching portions, the lower surfaces of the attaching portions being higher than the lower surface of the cover body. The attaching portion includes a cylindrical portion having a fastening member insertion hole and a receiving portion provided at the lower end of the cylindrical portion and having an insertion hole. The fastening member has a head portion of a diameter larger than that of the insertion hole formed in the receiving portion, a columnar portion connected to the head portion and having a diameter smaller than that of the insertion hole but is larger than that of a threaded hole formed in the upper case board, and a threaded portion that is connected to the columnar portion and that can be screwed into the threaded hole formed in the upper case board.

Abstract: A document feeder having a transportation belt unit for transporting a document original; a front side plate and a rear side plate respectively projecting upright at widthwise opposite edges of the transportation belt unit; a pair of stays each extending between the front side plate and the rear side plate; a front stay plate detachably fastened to portions of the pair of stays adjacent to the front side plate by means of a front fastening member; and a rear stay plate fastened to portions of the pair of stays adjacent to the rear side plate by means of a rear fastening member which can be loosened. The front side plate has a recess open to its underside for receiving the front stay plate for engagement therewith in a disengageable manner. The front stay plate is fastened to the front side plate in engagement with the recess by the front fastening member.

Abstract: An image-forming machine includes a photosensitive drum rotatably disposed; a charger for electrically charging the peripheral surface of the photosensitive drum to a predetermined polarity; a developer for developing an electrostatic latent image formed on the peripheral surface of the photosensitive drum into a toner image; a transfer device for transferring the toner image formed on the peripheral surface of the photosensitive drum onto a transfer paper; a fixing roller for heat-fixing the toner image transferred onto the transfer paper by the transfer device; and a cooling fan for blowing cooling air to the surrounding area of the fixing roller. A guide plate having a plurality of openings formed along its length, guides the transfer paper onto which the toner image has been transferred by the transfer device, to the fixing roller.

Abstract: An automatic document feeder for feeding documents borne on a document bearing table to an exposure position includes a two-document exposure setting switch for setting the conveyance of two documents to the exposure position and the simultaneous exposure of the two documents, and a controller. The controller controls the first and second documents fed from the document bearing table so that they are conveyed to the exposure position with the rear end of the first document and the front end of the second document overlapping by a predetermined amount.

Abstract: A simulation system is provided which is capable of simulating the behavior of a sheet transported by a transportation system. In response to application of a control sequence formulated for the sheet transportation system, a simulation is performed to check how the sheet is to be transported in the sheet transportation system on the basis of the applied control sequence. Necessary data are extracted from hardware systems constituting the real sheet transportation system. On the basis of the extracted data, a virtual sheet transportation system is constructed in a computer, and the sheet is represented by information indicative of the locations of opposite ends of the sheet and the distance therebetween. The sheet thus represented is moved by a predetermined unit distance in the virtual sheet transportation system on the basis of the control sequence, and data is computed for every movement of the sheet.

Abstract: An image forming apparatus has a paper discharging section provided in its main body. The paper discharging section opens toward the front of the main body. An opening serving as a window for introducing light into the paper discharging section is provided on a side surface of the main body. Light enters the paper discharging section through the opening, so that the paper discharging section is brightened. As a result, it is possible to easily visually confirm whether or not a paper sheet exists in the paper discharging section. Additionally, vent holes adjacent the window opening serve to introduce cooling air along the axis of a fusing roller.

Abstract: An exposure device in an image-forming machine, in which an optical lens unit is able to reciprocatingly move in the direction of the optical axis, and the image of a document is exposed to the photosensitive surface of a photosensitive material through the optical lens unit. The optical lens unit includes a lens-holding plate which is able to reciprocatingly move in the direction of the optical axis, a lens center-adjusting plate which is disposed on the lens-holding plate so as to pivot on a positioning vertical shaft and so as to be secured, a lens mounted on the lens center-adjusting plate, and a light quantity correction plate which is mounted on the lens center-adjusting plate so as to move in the radial direction relative to the center of the lens. A guide member is provided for moving the light quantity correction plate in the radial direction relative to the center of the lens with the reciprocating motion of the lens-holding plate in the direction of optical axis.

Abstract: A toner cartridge comprising a container having a toner discharge port, a toner contained in the container and a stirrer for stirring the toner existing in the container. The stirrer includes a rotary shaft rotatably mounted between both side walls of the container, not less than four arms extending in the radial direction from the rotary shaft at fixed distances in the axial direction and not less than three paddles disposed among the ends of the arms. The paddles are arranged at not less than three angular positions having angles different from each other and spaced at a distance apart in the circumferential direction.

Abstract: A method and an apparatus for measuring the toner concentration and the amount of electric charge, capable of simultaneously measuring the toner concentration and the amount of electric charge easily and maintaining high precision using a simple device.