摘要:
An image forming apparatus has a plurality of image forming stations capable of forming different images which are to be correctly registered and superimposed. Elimination of possible image misregistration in each image station is executed on the basis of the result of detection of register marks which are formed by each image forming station. The correction is executed at a timing which is independent from image forming sequences performed by each imgae forming station in accordance with image signals, e.g., during warming-up of the apparatus after the initial application of the power immediately after the input of image forming operation start instruction through a start key, or after completion of production of a predetermined number of copies counted from the last misregistration correcting operation.
摘要:
There is provided a multiimage forming apparatus for forming image data onto photo sensitive drums by an electrophotographic system. This apparatus comprises: an image forming circuit to form different images onto the photo sensitive drums; a transfer device to transfer the images on the drums onto the same transfer paper; a conveying belt to convey the transfer paper; a control circuit to control the image forming circuit so as to form registration marks to match the positions of the images onto the drums; CCD detectors to detect the recording positions of the marks; and a correcting circuit to correct at least two of the positional direction in the conveying direction of the belt, the positional deviation in the direction perpendicular to the belt conveying direction, the magnification of the image, and the inclination of the image on the basis of the detection outputs of the detectors. With this apparatus, the positional deviations of the images which occur during the image formation can be accurately corrected, so that the images can be accurately formed on the transfer paper by reading and matching the position matching registration marks.
摘要:
An image forming apparatus such as a laser beam printer has a plurality of movable image carrying members such as photosensitive drums, an image forming member such as a laser beam scanner capable of forming on the image carrying members images of different colors correspoding to image information, and transfer devices for sequentially transferring the image carried by the image carrying members to an image receiving member such that the image of different colors are superposed. The image receiving member may be copy paper or an overhead projector sheet, and is fed by a feeding device in the form of an endless belt. A lifting device is provided to move the feeding device from an operative position to at least one retracted position in response to detection of jamming or when an image receiving member having a large heat capacity is used.
摘要:
An image forming apparatus for forming superimposed images has a plurality of image holders each respectively for holding an image, a plurality of image forming stations for forming an image on the holders, and an adjusting device for adjusting positions of images formed on image holders except for that image station which is designated to be a standard station for adjusting or which is not used of image formation.
摘要:
An electrographic apparatus includes a plurality of photosensitive members, a plurality of laser projecting devices for projecting deflecting laser beams for scanning the photosensitive members, the laser projecting devices being provided for the respective photosensitive members, mirrors for receiving the laser beams projected from the laser projecting devices and reflecting them in a substantially reverse direction to scan the photosensitive members with the reversed laser beams, the mirrors being provided for the respective laser projecting devices. The apparatus may further includes adjusting devices, provided for the respective mirrors, for adjusting relative positions between the photosensitive members and associated ones of the mirrors.
摘要:
A sheet feeding apparatus for successively supplying, by one, sheets piled up within a sheet storing device up to an image formation apparatus along a predetermined sheet supplying direction. The sheet feeding apparatus is equipped with a sheet feeding roller driven to rotate about a roller rotating shaft to pick up the sheets from the sheet storing device and a separation device disposed at a downstream side of the sheet storing device and in opposed relation to the sheet feeding roller. The separation device is pressed by a spring toward the sheet feeding roller to be brought into contact therewith so that the sheets picked up from the sheet storing device are pressed against the sheet feeding roller so as to be frictionally separated from each other and fed by one in accordance with the rotation of the sheet feeding roller toward a downstream side. The sheet storing device is also pressed by a spring toward the sheet feeding roller so that the sheets can be brought into contact with the sheet feeding roller to be picked up therefrom. Also included in the apparatus is a releasing device operable in accordance with the rotation of the sheet feeding roller for releasing the pressed state of the sheets against the sheet feeding roller and for releasing the pressed state of the separation device against the sheet feeding roller when sheet feeding roller rotates by a predetermined rotational angle. This arrangement allows reduction of parts to reduce the cost and size of the apparatus.
摘要:
Utilizing an action of a transfer roller transferring a toner image formed on an intermediate transfer belt onto a sheet of paper can provide the belt with tension, and allows the belt and an urging roller to nip the sheet of paper. Thanks to this structure, a compact and inexpensive color image forming apparatus is obtainable.
摘要:
A color image forming apparatus comprises photoconductor drums on which toner images of each color are developed and formed; an endless intermediate transfer belt arranged in a contactable state with the photoconductor drums to run; first bias transfer rollers which perform first bias transfer in which the toner images of each color are transferred from the photoconductor drums onto the intermediate transfer belt; a second bias transfer roller which performs second transfer in which the toner images on the intermediate transfer belt are transferred onto paper; and a separation unit which, when a maximum print length of an image is below a length from a transfer point A to a transfer point B, separates the photoconductor drums and the intermediate transfer belt from each other after all first bias transfer of the toner images to be transferred on the last paper in a first print job has been completed, before second bias transfer onto the last paper is started and after second bias transfer onto paper immediately before the last paper has been completed.
摘要:
A driving force transmission apparatus achieves a high speed ratio and has a compact and inexpensive structure. The apparatus includes speed change elements including a cam portion, a gear, an internal gear and a correction plate, a connecting arrangement including a second clutch plate, a third clutch plate, an electromagnetic coil and a coil spring, and a first clutch plate, all arranged on a common shaft. This arrangement achieves both a high speed ratio and a compact and inexpensive structure.
摘要:
A drive transmission apparatus includes a first gear for transmitting a driving force to a first rotatable body, a second gear for transmitting the driving force to a second rotatable body and a third gear to which the driving force is transmitted from a driving source, the first, second and third gears being coaxially arranged. A first connecting member passes through the second gear and connects the first gear and the third gear. A cylindrical second connecting member is supported by the first connecting member located inside the second connecting member and connects the second gear and the third gear. The arrangement is such that the fluctuation in rotating speed of the second gear may be transmitted to the first gear through the second connecting member, the third gear and the first connecting member.