Abstract: When an original document is placed on the lift tray, a timer is reset and starts counting a predetermined time (S12). Whether an alignment device is moved to adjust the original documents loaded on the lift tray in, for example, the widthwise direction transverse to the transportation direction is then determined (S13). If a change in the detected width of the original documents is detected (S13 returns Yes), control returns to S12 and the timer is reset and started again (S12). If there is no change in the detected width of the original documents in S13, control waits for the timer set in S12 to time out (S14). If the timer reaches the predetermined time set in S12 (S15 returns Yes), the lift tray is driven up by the lift motor (S16) and rises until the top limit sensor turns on (S17).

Abstract: An image forming device includes an intermediate transfer member to which a toner image formed on an image bearing member is primarily transferred and which is able to simultaneously support a plurality of toner images, a secondary transfer member for secondarily transferring a toner image held on the intermediate transfer member to a sheet, a cleaning unit for removing the toner images from the intermediate transfer member after the secondary transfer, and a feeding member for feeding a sheet into the secondary transfer member. The secondary transfer member features a sheet-delay transfer mode in which a subsequent toner image on the intermediate transfer member is transferred if a previous toner image on the intermediate transfer member is out of sync with the timing at which the toner image is transferred to the fed sheet.

Abstract: The invention provides a stackless continuous dual-sided copying method in photocopying machines.

Abstract: An image forming apparatus which forms identical images both on a sheet of a first type (overhead projector sheet) and on a sheet of a second type (normal paper sheet). One-side image formation is performed to form images on front sides of OHP sheets which are then discharged into a non-sort bin. Two-side image formation is performed to form images on the both sides of normal paper sheets which are then sorted and discharged into sort bins. Thus, sets of document sheets for presentation can be prepared in a sorted state. Since images are formed on both sides of the normal paper sheets, the normal sheets can be economized and saved.

Abstract: An electrographic copying machine has a photoreceptor drum which moves so that a photosensitive layer on its surface is successively charged, exposed, developed and charge-removed. The photosensitive layer is made of an amorphous material. The drum surface is charged by a charger before a latent image is formed thereon through exposure. A voltage generator is provided which supplies the charger with a voltage to charge the drum surface. It takes time for the potential of the charged drum surface at the developing section to reach a predetermined potential from a potential higher than the predetermined potential due to a rise characteristic of the surface potential. A controller is provided which corrects an output voltage value of the voltage generator to a voltage value necessary for the drum surface to be charged at the predetermined potential in a predetermined number of charging operations performed until the surface potential reaches the predetermined potential.

Abstract: An image forming apparatus with a sorter which is capable of performing image formation even during the implementation of a post-process. The image forming apparatus includes the sorter which has a non-sort bin and sort bins for receiving sheets each formed with an image, and a post-processor for performing the post-process on sheets received by the sort bins. When an interruption mode is designated during the post-process, the image formation is permitted while the post-process is continuously performed. Further, the sorter is controlled to discharge a sheet formed with an image into the non-sort bin. Thus, the image formation can be performed concurrently with post-process. Since the sheet formed with the image is discharged into the non-sort bin which is adapted not to receive sheets to be subjected to the post process, a jam will not occur even if an error occurs during the post-process.

Abstract: In a copying processing performed several times from the depression of a copy button of a copying machine until the surface potential of the photoreceptor drum is stabilized, a voltage sufficiently high for correcting the rise characteristic of the photosensitive layer on the drum surface is applied to a charger. A main circuit having a controlling portion to realize this corrects the output voltage of the high-voltage generating circuit which applies a high voltage to the charger to a voltage value necessary for the drum surface to be charged at a stable potential level. The main circuit charges the drum surface at the stable potential level necessary for development from copying of the first sheet.

Abstract: A toner recovery roller having at least its outer peripheral part made of an insulator and rotated and driven in a predetermined direction is disposed in the vicinity of a position where an image carrier and a developing roller interact with each other, and a triboelectric charging member for triboelectrically charging an outer peripheral surface of the toner recovery roller to a polarity opposite to that of toner particles is so provided as to be brought into contact with the outer peripheral surface of the toner recovery roller.The rotation of the toner recovery roller in a predetermined direction causes friction between the friction charging member and the insulating outer peripheral surface of the toner recovery roller, so that the insulating outer peripheral surface of the toner recovery roller is triboelectrically charged to a polarity opposite to that of toner particles. Therefore, toner particles scattered from the developing roller are attracted to the toner recovery roller to adhere thereto.

Abstract: An image forming apparatus which facilitates the input and output of copy paper. One embodiment includes an image forming apparatus with paper supply trays, a development area, a console and a sorter. By pressing a transparent paper mode key on the console, normal and projector paper are sequentially fed from the trays to the development area and then to the sorter. The sorter is set in one of three modes by a sorter instructor. A manual key on the console allows an operator to set the instructor to position the sorter in any one of the three modes. The pressing of the transparent paper mode key or the detection by a detector of transparent paper in the feeding tray results in the instructor setting the sorter in a non-sort mode despite the sort instructor having been previously set in a different mode.

Abstract: An image forming apparatus having a potential sensor for measuring a potential at the surface of a photoreceptor drum; a voltage generation circuit for generating a voltage lower than a voltage to be actually induced at the surface of the photoreceptor drum in the course of image formation; switching means for switching a condition so that the photoreceptor is connected to the voltage generation circuit or earthed; and charger-output control means for obtaining a value of a surface potential of the photoreceptor measured by the potential sensor at the time when a voltage form the voltage generation circuit is applied to the photoreceptor by operating the switching means, estimating by arithmetic operation, on the basis of the measured value thus obtained, a value to be measured by the potential sensor when a high voltage is actually induced at the photoreceptor surface in the course of the image formation, and controlling an output from the charger based on the value estimated by the above arithmetic operatio