Abstract: An image forming apparatus is provided which includes a switching mechanism which selectively shifts developing rollers among an all-color non-contact state in which all photosensitive members are kept apart from the corresponding developing rollers, a black contact state in which only the photosensitive member for black is kept in contact with the corresponding developing roller, and an all-color contact state in which all the photosensitive members are kept in contact with the corresponding developing rollers, and a control section which, when an operation mode of the apparatus is shifted from a color mode to a monochrome mode, causes the switching mechanism to shift the developing rollers from the all-color contact state to the all-color non-contact state to perform a transferring process to once transfer developing agents from recovery members onto the corresponding photosensitive members and further transfer the developing agents from the photosensitive members onto a transfer belt.

Abstract: A belt-conveyor device includes a detecting unit that detects a belt position in a width direction of the endless belt for a plurality of times within more than a cycle of the endless belt, the width direction being a direction orthogonal to direction of travel of the endless belt; an average calculating unit that calculates an average belt position from the belt positions detected by the detecting unit; a storing unit that stores therein a plural sets of correction values and belt positions; and a meander correcting unit that corrects meander of the endless belt based on a correction value that corresponds with the average belt position in the storing unit.

Abstract: An endless belt is extended over extending rollers, and carries a toner image transferred from an image carrier or a transfer sheet. The endless belt includes a front-side reinforcing member and a rear-side reinforcing member, and a guide member for preventing meandering fixed over an approximately entire circumference on the rear-side reinforcing member. The extending rollers include a step portion provided in an end area in an axial direction facing to the rear-side reinforcing member, which has a diameter smaller than a center area in the axial direction. The front-side reinforcing member has a width wider than a width of the rear-side reinforcing member.

Abstract: An image forming apparatus includes an image transferring device having a belt transfer unit for effectively performing an image transfer operation. The belt transfer unit includes a transport mechanism transporting a toner image, a scale provided around an entire perimeter of a surface of the transferring member and including at least one colored resin layer, and a scale reading mechanism arranged facing the scale and reading the scale. With the above-described belt transfer unit, a feedback control can effectively be performed to maintain constant reading accuracy and to prevent a voltage leak from a transfer mechanism.

Abstract: A transfer device is provided for an image forming apparatus designed such that toner images formed on a plurality of image bearing members are transferred one over another on a transfer body disposed in contact with each of the image bearing members with predetermined pressure and thus a toner image in two or more colors is formed on the transfer body. The transfer device includes a pressure varying mechanism which is capable of separating the transfer body from at least some of the image bearing members, and capable of varying transfer pressure between the image bearing members and the transfer body in contact with said image bearing members.

Abstract: An image forming apparatus includes a developing unit which develops toner to form an image, a transfer unit which transfers the image onto a printing medium, and a fusing unit to fuse the image transferred onto the printing medium, wherein the transfer unit includes a belt, a plurality of rollers which rotatably supports the belt, and a belt tension applying unit which moves a first roller of the plurality of rollers between a belt tension release position at which a tension of the belt releases and a belt tension applying position at which the tension of the belt applies by the interlocking motion between the belt tension applying unit and a second roller of the plurality of rollers.

Abstract: An image forming apparatus includes a plurality of rotors, and an endless belt that is supported with tension by the plurality of rotors and rotated by the rotors. Herein, at least one of the plurality of rotors is provided, at a first end, with a belt restraining member that has a restraining face for restraining displacement of the endless belt toward the first end and that is rotatable with respect to the rotor; and the belt restraining member is arranged such that an angle between the restraining face of the belt restraining member and a rotation shaft of the rotor is greater at a contact start point at which the endless belt begins contact with the belt restraining member during rotation than at a contact end point at which the endless belt ends contact with the belt restraining member during rotation.

Abstract: In a method for control of circulation speed of an endless belt arranged in a printer or copier, the endless belt is directed over at least two rollers where the belt is driven with a preset first circulation speed via at least one of the rollers as a driven roller. Various load states act on the endless belt in successive operating phases during a printing or copying process, and via said various load states the belt being braked with different strengths so that a slippage is generated at least between the belt and the driven roller. A braking force acting directly on the endless belt is generated. Braking force is controlled such that a substantially constant slippage is generated between the driven roller and the belt based on the operating phases so that the endless belt is braked to a second circulation speed.

Abstract: An image forming device has image forming units 3-6, a transfer belt 7, a position detection unit 19, a concentration sensor 23, and an adjustment unit. A toner image is formed on the surfaces of the image forming units 3-6, and transferred onto the transfer belt 7. The position detection unit 19 detects a predetermined position on the surface of the transfer belt 7. On the predetermined position, the concentration sensor 23 detects first information relating to the color of the surface of the transfer belt 7. The concentration sensor 23 detects second information relating to the color of the pattern image that is formed on the predetermined position. The adjustment unit adjusts toner concentration at the time of forming an image based on the first information and the second information detected by the concentration sensor 23.

Abstract: A belt driving apparatus for driving a belt has the belt hung around and between rollers, and has a meandering prevention member provided in each end part of each roller to restrict the meandering of the belt in the roller axial direction. A cut is formed to be open toward the roller end face and to extend in the roller axial direction, and a boss that fits into the cut is formed on the inner circumference of the meandering prevention member.

Abstract: A color image forming apparatus of a so-called tandem type which has image forming units in correspondence with colors is provided. In the color image forming apparatus, a color discrepancy amount storage unit stores information of a color discrepancy amount of each of the image forming units, which is measured in advance. A first color discrepancy correcting unit performs color discrepancy correction in a pixel unit by performing coordinate conversion of bitmap data to be printed based on the information of the color discrepancy amount stored in the color discrepancy amount storage unit. A second color discrepancy correcting unit performs color discrepancy correction in less than a pixel unit by performing tone correction of the bitmap data corrected by the first color discrepancy correcting unit based on the information of the color discrepancy amount stored in the color discrepancy amount storage unit.

Abstract: An image forming apparatus includes a belt unit having a support roller, a tension roller, a pair of side frames, a belt, and a guiding mechanism. The pair of side frames are configured to support the support roller and the tension roller. The belt extends across the support roller and the tension roller. The guiding mechanism are configured to guide the tension roller of the belt unit.

Abstract: An image forming apparatus can improve an accuracy of conveyance of a recording medium with a simple structure and prevent a reverse flow of mist so as to stably form a high-quality image. A conveyance belt (21) conveys a recording medium (12) by attracting the recording medium by an electrostatic force generated by electric charges applied thereto. A recording head (7) discharges droplets of a recording liquid toward the recording medium (12). An amount of electric charges induced on a surface of the recording medium (12), which has been conveyed to a recording position where the droplets of the recording liquid are discharged from the recording head (7) toward the recording medium (12), is adjusted in accordance with a resistance value of the recording medium (12).

Abstract: In an image forming apparatus, a toner image formed on a photosensitive drum is primarily transferred onto an intermediate transfer belt. The toner image on the intermediate transfer belt is secondarily transferred onto a transfer material by a secondary transfer roller in contact with the intermediate transfer belt. A relation A>B>C is satisfied, where A is a width of the intermediate transfer member, B is a width of the secondary transfer member, and C is a width of the transfer material. The intermediate transfer member includes a patch-pattern forming area that is not contacted by the secondary transfer member. The image forming apparatus includes a reflection-type photosensor that detects a patch pattern formed in the patch-pattern forming area.

Abstract: A drive roller is adapted for use with an image forming device that includes a conveyer belt trained on the drive roller. The drive roller includes an elongated roller body and symmetrical first and second threads. The roller body has a first segment that has an annular first surrounding surface, and a second segment that is opposite to the first segment, that has a length equal to that of the first segment, and that has an annular second surrounding surface. The first and second threads are formed respectively at the first and second surrounding surfaces, are threaded in opposite directions, and are adapted for contacting the conveyer belt.

Abstract: An image recording apparatus includes: a transfer roller that transfers an image formed on a photoconductor drum onto continuous paper pressed against the photoconductor drum; and guide rollers that regulate the position of the continuous paper with respect to the photoconductor drum.

Abstract: An image formation apparatus belt, includes: a belt that includes a belt main body, the belt having a recess; and a detected part for position detection that is located in a side margin of the belt, the detected part being placed in the recess provided in the belt.

Abstract: A color laser printer includes a plurality of photosensitive drums and a paper-conveying belt disposed in confrontation with the photosensitive drums. The paper-conveying belt conveys a sheet of paper as the photosensitive drums sequentially transfer toner images thereon. This printer also includes a tension-adjusting mechanism capable of adjusting the tension state produced in the paper-conveying belt, and a controller for controlling the tension-adjusting mechanism. Through the control of the controller, the tension-adjusting mechanism is capable of adjusting the tension state of the paper-conveying belt between a first tension state used for transferring toner images from the photosensitive drum, and a second tension state producing a tension greater than that produced by the first tension state for performing a cleaning operation.

Abstract: A belt driving controller includes a driving roller connected to a driving axis, a plurality of driven rollers, an endless belt provided to surround the driving roller and the driven rollers in a tensioned state, a motor connected to the driving axis via a reduction mechanism; a first detector provided near the driving axis and configured to detect a rotation angle of the driving axis, a second detector configured to detect a displacement of the endless belt, and a control unit configured to control driving of the endless belt.

Abstract: An image-forming device includes: a housing; an endless belt; a plurality of process units; and a plurality of scanner units. Each scanner unit and each process unit are inclined obliquely to a vertical direction. At least a part of each process unit is inserted into and removed from the housing in an obliquely inclined direction.

Abstract: An image forming apparatus for forming an image on a recording medium, includes: a belt-like member that is capable of cyclic rotation; a plurality of support members, along which the belt-like member is stretched; a first member that is located along an inner face of the belt-like member; and a regulator that is located opposite the inner face of the belt-like member, wherein the regulator maintains a cyclic rotating state for the belt-like member while ensuring the first member is separated by a gap from the belt-like member.

Abstract: A tandem type color image forming machine comprises a plurality of image forming units, a belt mechanism comprising an endless belt including a linear moving area, and a paper feed cassette in its image information machine body. The image forming units are arranged along the linear moving area of the belt with a space therebetween. The belt mechanism is arranged longitudinally so that the linear moving area of the belt extends almost in the vertical direction. The paper feed cassette is arranged longitudinally in the lateral direction of the belt mechanism or below the belt mechanism.

Abstract: An image forming apparatus is constituted by an image bearing member rotatable while bearing a toner image; and a transfer member for transferring the toner image onto a transfer medium, the transfer member forms a nip with the image bearing member while the transfer medium is movable through the nip in a plane including the nip so that the transfer medium moves in a direction inclined with respect to a movement direction of the image bearing member.

Abstract: An image forming apparatus includes: a plurality of rollers; and an endless belt wound around said rollers, said rollers including: a driving roller which drives said belt wound around said rollers and a driven roller set which is driven by said driving roller via the movement of the endless belt, said driven rollers having one or more metal rollers. At least one of said metal rollers is a smooth roller which satisfies following conditions (i) and (ii); (i) a surface roughness Rz?2 ?m; and (ii) an arithmetic inclination average ?a?0.06; where said ?a is obtained from an equation (1) below: ? ? ? a = 1 L ? ? 0 L ? ? ? ? x ? f ? ( x ) ? ? ? x ( 1 ) where L=a reference length taken from a roughness curve; f (x)=a height of the roughness curve at a position x within said reference length L along a lengthwise direction of the roller.

Abstract: An image forming apparatus includes: a rotating belt which rotates around a roller; a drive section which rotates the belt; a detection section which detects a position of the belt in a width direction; a moving section which moves the belt in the width direction; a control section which corrects a deviation of the belt by controlling the moving section. The control section conducts a preparatory operation in which the control section changes an amount of control to be given to the moving section under the condition where the belt is rotated to obtain a correction data showing a relation between the amount of control and a change of a position of the belt in the width direction detected by the detection section, stores the correction data in a memory section, and then corrects the deviation based on the correction data stored in the memory section.

Abstract: In an image-forming device, a belt unit is detachably mounted in the housing. The belt unit moves to an installation position along a linear insertion/removal path in an insertion direction when the belt unit is mounted in the housing. The belt unit includes: a plurality of rollers; and an endless belt that is supported by the plurality of rollers and is capable of moving circumferentially around the plurality of rollers. A surface of the endless belt contacts a surface of the at least one photosensitive member when the belt unit is located in the installation position. The endless belt moves in a belt-moving direction that is angularly shifted from the removal direction to allow the surface of the endless belt to separate from each photosensitive member when the belt unit starts moving in the removal direction from the installation position.

Abstract: In a black monochromatic mode, an intermediary transfer belt is separated from an upstream photosensitive drum in a state in which a downstream photosensitive drum contacts the intermediary transfer belt. At this time, a stretching roller is moved upwardly in interrelation with a contact-separation mechanism to increase an angle of contact of the intermediary transfer belt with the downstream photosensitive drum compared with the case of a full-color mode. On the other hand, in the full-color mode, the stretching roller is moved downwardly to be separated from an inner surface of the intermediary transfer belt.

Abstract: A belt includes a surface layer and an underlayer. An interface between the surface layer and the underlayer is roughened to irregularly reflect incident light.

Abstract: An endless belt including a belt main body in which a ten-point average roughness (Rz) of an inner peripheral surface thereof is in a range of 2.0 ?m or higher and 10.0 ?m or lower and an average distance (Sm) between projections and depressions of the inner peripheral surface is in a range of 50 ?m or higher and 200 ?m or lower, and a guide portion in which an average distance (Sm?) between projections and depressions on an adhesive surface thereof adhered to the inner peripheral surface of the belt main body along an edge of the belt main body is two times or higher and six times or lower the average distance (Sm) between projections and depressions in the inner peripheral surface.

Abstract: An endless belt drive controlling apparatus includes an endless belt and its drive unit, a first detector that detects a belt mark, a second detector that detects a detected angular displacement error of an encoder generated due to a variation in a thickness of the endless belt, a first calculating unit that calculates a phase and a maximum amplitude of the endless belt at the belt mark based on the detected angular displacement error of the encoder thus obtained, and a second calculating unit that calculates a position of the endless belt at which the detected angular displacement error is a minimum from the phase stored in a nonvolatile memory. The drive unit controls the endless belt so that the portion thereof at which the detected angular displacement error is the minimum is stopped at one of the rollers at which a highest tension is applied to the endless belt when the driver issues a belt stop command.

Abstract: A device and a method are provided for recharging a belt conveyor which is used for transporting a printing medium in the transfer area of an electrophotographic printer or a copying machine. The device includes a blade-like contacting element which is adjacent to the belt conveyor and arranged transversally with respect to the forward motion thereof. The contacting element makes it possible to transfer an electric charge to the belt conveyor and is mounted on a bearing element which can be inserted into a printer or a copying machine and withdrawn therefrom. A method is provided for controlling a printer or copier device by which errors, such as paper jams, can be cleared automatically. A controller commands a module having the error to clear the error automatically. The commands are sent to modules beginning at the output of the printer or copier device and moving in a reverse direction to the paper flow direction of the printer or copier so as to automatically clear errors such as paper jams.

Abstract: There is provided an image forming apparatus including a belt which conveys images, first rollers which support the belt and a second roller which supports the aforementioned belt at its surface opposite from the surface supported by the aforementioned first rollers, wherein the image forming apparatus rotates the aforementioned belt at a first speed and rotates the aforementioned belt at a second speed smaller than the aforementioned first speed or stops the aforementioned belt when the portions of the aforementioned belt which have been supported by the aforementioned first rollers at the time of stoppage of the aforementioned belt are supported by the aforementioned second roller, prior to image formation after the stoppage of the aforementioned belt.

Abstract: In a method and a system for generation of print images on a carrier material, an actual speed difference is generated in a transfer printing region between an image carrier and the carrier material. A deviation of the actual speed difference from a desired speed difference is determined with aid of a measurement arrangement.

Abstract: A belt drive device includes: a plurality of rollers; an endless belt placed on the rollers to be movable; a roller shaft shifting member disposed on at lease one end portion of a shaft of at least one of the rollers for shifting the one end portion of the shaft of the one of the rollers according to a movement of the endless belt in a shaft direction of the one of the rollers; a cleaning member disposed to face the one of the rollers; and a shifting member for shifting the cleaning member in the shaft direction of the one of the rollers when the endless belt moves in the shaft direction of the one of the rollers.

Abstract: A color image forming apparatus includes an intermediate transfer member, a first forming portion having a first transfer unit, a second forming portion provided downstream from the first forming portion, a third forming portion provided downstream from the second forming portion, a fourth forming portion provided downstream from the third forming portion, and a control portion. The control portion controls a bias of at least one of the corresponding developing unit and the corresponding transfer unit, when transfer of the toner image from the intermediate transfer member to the recording medium is completed, so that a toner-image residue toner material resting on the intermediate transfer member is returned to the corresponding developing unit through the image bearing member of at least one of the first to fourth forming portions.

Abstract: A belt unit includes a drive roller, a follower roller and an endless belt looped around the drive roller and follower roller, and formed of a resilient material. The drive roller transfers a first force based on the driving force to the endless belt to circularly move at a first velocity at a first boundary between the drive roller and the endless conveying belt. The first velocity provides a first fluctuation. The endless belt transfers a second force based on the first force to the follower roller to rotate. The endless belt moves at a second velocity at a second boundary between the follower roller and the endless belt. The second velocity provides a second fluctuation. A transmission parameter with respect to at least one of the drive roller, the follower roller and the endless belt is set so that the second fluctuation is smaller than the first fluctuation.

Abstract: An image forming apparatus includes first and second toner image forming sections and a transfer unit. The first and second toner image forming sections include first and second image carriers and first and second intermediate transfer members, respectively. The color toner images are formed on the image carrier and then transferred onto the intermediate transfer member to form a composite color toner image on the intermediate transfer member. In a first mode, the first and second toner image forming sections form both the composite dark and light color toner images on the recording material. In a second mode, the second intermediate transfer member is moved out of contact with the transfer unit and the second image carrier and the second intermediate transfer member are not operated, so that only the first toner image forming section forms the composite dark color toner image on the recording material.

Abstract: The image formation by the plural-image formation mode is manually inhibited by the user in case the image formation is interrupted or the formed image is distorted by defective original feeding in the image formation by such plural-image formation mode. As a result, image formation of high quality can be achieved without trouble. The configuration for this purpose is featured by manually inhibiting the plural-image formation mode by depression of a touch key on an operation unit.

Abstract: The color image forming apparatus comprises a transfer belt device which feeds a transfer member such as a paper and a plurality of image forming units. The image forming units are disposed facing towards the transfer belt device. The transfer belt device, at least in a portion in which the image forming units have been disposed, is arranged such that it is inclined with respect to the ground. Each of the image forming unit forms a desired image and sequentially transfers the formed image on the transfer member fed by the transfer belt device.

Abstract: A scale including equally spaced marks is attached to a belt in a direction of movement of the belt such that a gap is formed between a first end and a second end of the scale. A first sensor and a second sensor detect the marks on the scale and output first signals and second signals respectively upon detecting the marks. The first sensor and the second sensor are located at different positions along the direction. A controlling unit controls the speed based on any one of the first signals and the second signals according to a position of the gap detected by the first sensor and the second sensor.

Abstract: An image forming apparatus having the improved construction and mounting structure of a device for charging paper to be attached to a paper feed body is disclosed. The image forming apparatus includes a plurality of developing devices and a paper feed body which is mounted opposite to the plurality of developing devices and rotates to feed paper. A sheet member is mounted to a developing device of the plurality of developing devices, which is disposed on an uppermost paper stream side in a feeding direction of the paper. The sheet member charges the paper as it advances to the paper feed body to attach the paper to the paper feed body. The image forming apparatus further includes a voltage transmission part which transmits high voltage to the sheet member.

Abstract: An image forming apparatus includes a first stretching member, contacted to a belt member at a first contact area, for stretching the belt member; a second stretching member, contacted to a belt member at a second contact area, for stretching the belt member, wherein a plurality of transfer areas is disposed between the first contact area and the second contact area which are adjacent to each other, and the plurality of transfer areas include a first transfer area which is closest to the first contact area; and an abutting member for abutting the belt member at a position between the first transfer area and the first contact area. The abutting member and the first contact area are disposed downstream of the first transfer area, and the first transfer contact area is disposed downstream of the abutting member, with respect to a direction of movement of the belt.

Abstract: A belt unit includes an endless belt and a cleaning member. The endless belt has a value of ten-point height of roughness Rz not larger than 0.2 ?m, a value of shininess not less than 100, a creep not larger than 0.03%. The cleaning member is in contact with said endless belt and removes foreign matter adhering to said endless belt. The belt unit may be applied to an image forming apparatus either of direct transfer type and intermediate transfer type.

Abstract: An image forming apparatus includes: a plurality of rollers including at least one drive roller to be rotatively driven; a belt passed around the plurality of rollers; and a press member which is disposed opposite the drive roller with the belt interposed therebetween and presses the belt against the drive roller.

Abstract: An image forming apparatus includes an electrophotographic process part for image formation provided for an image carrying medium for each color; a non-end moving part moving images transferred thereto from the respective image carrying media for the respective colors; and an image detecting part detecting an image formed on the non-end moving part. The respective electrophotographic process parts are disposed in sequence along the non-end moving part, and form positional error detection marks on the non-end moving part; the image detecting part detects the thus-formed positional error detection marks; and positional error correction is performed based on a result of detection thus performed by the image detecting part. The apparatus comprises a control part having at least two modes in the positional error correction; and the control part performs control such that one of the at least two modes is selected according to a positional error amount detected by the image detecting part.

Abstract: The image forming apparatus includes a belt member having a convex portion, effecting a circular movement, a first support member and a second support member for supporting the belt member, and a drive receiving unit for receiving force from circular movement of the belt member. An angle of the second support member to the first support member is affected by inputting the force arising from the circular movement into the drive receiving unit, and the force arising from the circular movement is input by contacting convex portion to the drive receiving unit.

Abstract: A device for electrically charging a transport belt for transport of recording media in a transfer printing area of an electrographic printer or copier as well as a method for charging. In a direction transverse to a running direction of the transport belt, a contact element is arranged bearing against the transport belt and via which electric charge is transferred to the transport belt, the contact element comprising a contact lip which is substantially comprised of a rubber material and which bears against the transport belt.

Abstract: A belt driving control apparatus, the belt driving control apparatus having an endless belt, a driving roller driving the endless belt, a driving motor driving the driving roller, at least one idler roller being dependent on the endless belt, and an encoder attached to one idler roller. The belt driving control apparatus includes a structure where a control target value of the driving motor is set so that an effective speed of the endless belt is constant and the driving motor is drive-controlled so that the control target value is satisfied.

Abstract: The image forming apparatus, includes a conveyor belt for bearing a recording material, capable of suppressing an image blur caused by a separating discharge at the separation of the recording material from the conveyor belt. To fix record materials on a transportation belt, the recording material is charged by a adhering member to electrically adhere the recording material to the conveyor belt. When the recording material is separated from the conveyor belt, a separating discharge occurs between the recording material and the conveyor belt, as the recording material is charged. In order to reduce the faulty of the toner image on the recording material caused by the separating discharge, the voltage applied to the adhering member is controlled for example according to a current which the recording material receives at the transfer position to mutually cancel the charge received at the transfer position by the adhering member.

Abstract: The image forming apparatus includes a belt member having a convex portion, effecting a circular movement, a first support member and a second support member for supporting the belt member, and a drive receiving unit for receiving force from circular movement of the belt member. An angle of the second support member to the first support member is affected by inputting the force arising from the circular movement into the drive receiving unit, and the force arising from the circular movement is input by contacting the convex portion to the drive receiving unit.