Abstract: This invention relates to an image forming apparatus for recording an image on recording paper. The apparatus has a main base frame internally provided with an imaging unit for recording an image on recording paper, an upper frame disposed on-the main base frame and pivotally movable about an axis of a pivot provided on one end of the upper frame corresponding to a rear side of the apparatus to open a front side of the apparatus, a document feeder unit disposed on the upper frame for feeding an original document set thereon toward the front side, a document discharge tray attached to the main base frame for receiving the document fed by the document feeder unit, and a recording paper discharge tray attached to the main base frame beneath the document discharge tray for receiving the recording paper carrying the recorded image. The document discharge tray and the recording paper discharge tray are integrally attached to the main base frame via a tray frame to form a one piece unit.

Abstract: An image forming apparatus of this invention is constructed such that a main base frame constituting the apparatus is formed with a pair of first positioning pins. An attachment member is formed with a pair of second positioning pins and positioning holes for fittingly receiving the first positioning pins therein to position the attachment member relative to the main base frame. A brake force supplier formed with mounting holes is attached to the attachment member while positioned relative thereto by fitting insertion of the second positioning pins in the mounting holes. When the attachment member is not used, another brake force supplier can be directly mounted on the main base frame and positioned relative thereto by fitting insertion of the first positioning pins in mounting holes of the brake force supplier.

Abstract: This invention relates to an image forming apparatus constructed such that an upper frame is openably mounted on a main base frame and a pivotal movement transmitter (gear) is rotatably mounted on the upper frame about an axis of a rotation of the upper frame, i.e., in association with the rotation of the upper frame. The gear has a cam portion. One end of a lever comes into contact with part of the cam portion of the gear, while the opposite end of the lever comes into contact with a coil spring. Further, a distance from the pivotal axis of the gear to the contact position of the lever with the cam portion decreases in accordance with a proceeding of the closing operation. Accordingly, as the lever (cam follower) follows the cam portion in accordance with the closing operation of the upper frame, a compression force to compress the coil spring increases. Thereby, a brake force applied to the upper frame on the way of closing also increases.

Abstract: An image forming apparatus includes a mount portion which permits a cassette containing a plurality of stacks of sheets arranged side by side in rows to be mounted to the image forming apparatus; a feeder for feeding sheets side by side in a state where the cassette is mounted to the mount portion; an imaging assembly for forming an image on each of the sheets being fed side by side; a sheet sensor for detecting the presence or absence of a sheet contained in the cassette for each row; and a control unit for, when the absence of a sheet is detected in any of the rows, stopping at least an image forming operation along a corresponding transport path. Accordingly, even if all the sheets run out in any one of the rows, the corresponding transport path and the like can be prevented from getting smeared due to the image forming operation carried out despite the fact that no sheets are being fed.

Abstract: A sheet feeder includes a feeder for feeding a sheet, a cassette for containing a plurality of stacks of small sized sheets side by side therein, the cassette including a plurality of biasing members for biasing the respective stacks of small sized sheets upwards so as to bring uppermost sheets of the respective stacks into contact with the feeder, a plurality of sheet detectors arranged in positions corresponding to the respective stacks of sheets for detecting the height of the respective stacks of sheets contained in the cassette, and a controller responsive to the plurality of sheet detectors for determining the absence of sheet in the cassette when at least one of the plurality of sheet detectors detects that the height of the stack has become lower than a predetermined height, and stopping a sheet feeding operation. This sheet feeder prevents the transfer device of an image forming apparatus from being smeared due to the fact that the small sized sheet is fed from only one stack.

Abstract: An image-forming machine having a conveying passage for conveying a sheet material through a transfer zone, a first and a second feed device for feeding the sheet material to the conveying passage, a first feed passage for conducting the sheet material delivered from the first feed device to the conveying passage, a second feed passage for conducting the sheet material delivered from the second feed device to the conveying passage, and a first and a second opening-closing member for opening and closing the first and second feed passages. Various improvements are made on the first and second opening-closing members.

Abstract: An image-forming machine comprising a conveying passage for conveying a sheet material through a transfer zone, a first and a second feed system for feeding the sheet material to the conveying passage, a first feed passage for conducting the sheet material delivered from the first feed system to the conveying passage, a second feed passage for conducting the sheet material delivered from the second feed system to the conveying passage, and a first and a second opening-closing member for opening and closing the first and second feed passages. Various improvements are made on the first and second opening-closing members.

Abstract: A supporting and driving mechanism including a rotatable body and a supporting unit for assuring stable support and rotation of the rotatable body for a long time. The mechanism includes an axis member at either end of the rotatable body, a driven gear at one end of the rotatable body, two rollers and a driving gear of the supporting unit. The two rollers are placed parallel to each other and the distance between the closed surfaces of the rollers is smaller than the diameter of the axis member of the rotatable body. The driving gear engages the driven gear and transmits a driving force to the driven gear of the rotatable body. The driving force applied from the driving gear to the driven gear directs between the centers of the two rollers when the driving force is translated so that the origin of the force is brought to the center of the axis member of the rotatable body.

Abstract: A copying machine, including a photosensitive drum; a corona charger; an exposure device for exposing the photosensitive drum to an optical image of an original; a developing unit for developing a toner image on the photosensitive drum; a transfer corona charger for transferring the developed toner image to copy paper; a device for mechanically separating the imaged copy paper from the photosensitive drum; and a system for cleaning the drum after the image transfer, which includes an eraser lamp disposed adjacent the copy paper delivery side of the transfer corona charger at a position for illuminating copy paper from the rear side thereof upon image transfer thereto, and a control unit for controlling the operation of the transfer corona charger and the eraser lamp, thereby assuring smooth separation of copy paper after image transfer and efficient transport of the paper.