Abstract: Parallel printing systems include first and second adjacent electronic printers and at least one sheet bypass section extending around the second electronic printer to provide a sheet transporting path overlying the second electronic printer and bypassing the second electronic printer. The sheet bypass section includes an output for merging printed sheets from the first electronic printer with printed sheets printed by the second electronic printer. The output preferably comprises a intermediate transport section having a first input aligned with the output of the bypass section and a second input aligned with the output of the second electronic printer.

Abstract: A method and device for moving media sheets along a media path. In one embodiment, the media path comprises a metering nip, at least one transfer nip downstream from the metering nip, and a feed nip upstream from the metering nip. The feed nip moves the media sheet initially at a faster speed than the metering nip. This speed variation causes a buckle to form in the media sheet that aligns the leading edge. The media sheet is then moved from the metering nip into the transfer nip. The metering nip may move the media sheet at a faster speed than the transfer nip again forming a buckle in the media sheet. As the media sheet is moved through the transfer nip, it is tacked to a transfer belt such that it moves consistently through the remaining downstream transfer nips.

Abstract: An image reading device is operable in a manually placed document reading mode offered by a manually placed document reading section and an ADF document reading mode offered by an ADF document reading section. Reading mode detecting section detects in which mode a document to be read is in. First reading-speed setting section sets a reading speed of the ADF document reading section to a predetermined reading speed, upon detection by the reading mode detecting means that the document to be read is in the ADF document reading mode. Second reading-speed setting section sets a reading speed of the manually placed document reading section to a predetermined reading speed sufficient to reduce image vibration caused by reading by the manually placed document reading section, upon detection by the reading mode detecting section that the document to be read is in the manually placed document reading mode.

Abstract: An image forming apparatus in which the rotational speed of register rollers is calculated at first to fourth stations at a transfer belt drive system, and transfer feedback control for varying the speed of a transfer drive motor is carried out on the transfer drive motor so that the speed of movement of a transfer belt is maintained at a predetermined value. The transfer feedback control is carried out on the image forming apparatus so as to vary the speed of the transfer drive motor so that the speed of movement of the transfer belt is maintained at a predetermined value or so as not to vary the speed of the transfer drive motor as a result of not carrying out the transfer feedback control.

Abstract: A belt apparatus having an endless belt which is wound around and movably driven by a plurality of support rollers. The speed fluctuations of the endless belt due to the variations in thickness of the endless belt are prevented. A driving apparatus for driving the endless belt has a driving roller and an opposite roller facing with each other across the endless belt, and a driving motor for driving the driving roller, the driving roller and the opposite roller being in pressure contact with each other only at both end parts in their axial direction via the endless belt and the pressure contact part forming a plane.

Abstract: An image forming apparatus in which the rotational speed of register rollers is calculated at first to fourth stations at a transfer belt drive system, and transfer feedback control for varying the speed of a transfer drive motor is carried out on the transfer drive motor so that the speed of movement of a transfer belt is maintained at a predetermined value. The transfer feedback control is carried out on the image forming apparatus so as to vary the speed of the transfer drive motor so that the speed of movement of the transfer belt is maintained at a predetermined value or so as not to vary the speed of the transfer drive motor as a result of not carrying out the transfer feedback control.

Abstract: An image forming apparatus is configured to develop a latent image corresponding to a line-like image of a predetermined pitch on photosensitive bodies provided for respective colors for a color image formation and rotatable about a predetermined axis and transfer the developed image to a transfer belt. The apparatus detects the presence or absence of any line from the transferred line-like image for respective colors and calculates a phase displacement, from a phase of a reference photosensitive drum, of the phases of the other photosensitive drums on the basis of waveforms calculated from the detected line pitches for respective colors. The apparatus adjusts the rotation positions of these other photosensitive drums to allow the phases of these other photosensitive bodies to be substantially matched to the phase of that given photosensitive body.

Abstract: An image forming apparatus and image forming method including a low-noise mode at paper sheet reverse section to decrease a reverse convey speed of reverse conveyance by a reverse roller pair, where necessary, a reverse convey speed of reverse conveyance.

Abstract: A method of controlling the velocity of a copy substrate in an electrophotographic reproduction machine which includes a substrate registration system for transporting and registering the substrate and a toner image traveling to a toner image transfer point at a transfer velocity. The method includes decelerating the substrate from a process velocity to a low velocity, where the transfer velocity is greater than the low velocity and less than the process velocity, registering the substrate via the substrate registration system, and accelerating the substrate to the transfer velocity for image transfer.

Abstract: There is provided an image forming apparatus that can suppress the formation of creases when forming images on both surfaces of a sheet and can greatly reduce the incidence of unprinted areas. The image forming apparatus has a sheet stacking section in which sheets are stacked, a sheet conveying section that conveys a sheet, an image forming section that forms an image on the sheet while the sheet is conveyed, a re-conveying section that again conveys the sheet with the image formed on a first surface thereof to the image forming section, and a sheet feeding section that feeds a sheet from the sheet stacking section or the re-conveying section to the image forming section.

Abstract: A sheet conveying apparatus has a first conveying unit for conveying a sheet, a second conveying unit for conveying a sheet in merging with the first conveying unit and a sheet merging overlapping device. At a junction between the first and second conveying unit, the sheet merging overlapping device overlaps the sheet conveyed by first conveying unit with the sheet conveyed by the second conveying unit in a sheet conveyance direction.

Abstract: There is provided an image forming apparatus that can suppress the formation of creases when forming images on both surfaces of a sheet and can greatly reduce the incidence of unprinted areas. The image forming apparatus has a sheet stacking section in which sheets are stacked, a sheet conveying section that conveys a sheet, an image forming section that forms an image on the sheet while the sheet is conveyed, a re-conveying section that again conveys the sheet with the image formed on a first surface thereof to the image forming section, and a sheet feeding section that feeds a sheet from the sheet stacking section or the re-conveying section to the image forming section.

Abstract: An image forming section forms images, which are transferred onto a primary medium. A medium cassette holds a stack of print medium. A remaining-medium detector detects the number of pages of remaining print medium held in the medium cassette. The image on the primary medium are transferred onto a print medium fed from the medium cassette. A controller changes a timing at which the image forming section forms the images, the timing being changed in accordance with the number of pages of remaining print medium. The timing is changed in such a way that the images are formed at greater distance intervals on the primary medium when the number of pages of the medium cassette in the medium cassette is equal to or less than a reference value than when the number of pages of the medium cassette in the medium cassette is more than the reference value.

Abstract: An image forming apparatus includes a main body including a sheet transport path having an output part and an image forming part for forming an image on a sheet, and a sheet discharging device located in the vicinity of the output part, and a sheet receiving part. The sheet discharging device discharges the sheet having an image formed thereon by the image forming part. The sheet receiving part receives the sheet discharged by the sheet discharging device. The sheet discharging device includes a discharging member, disposed in the vicinity of the output part, for transporting the sheet in a nipping manner, a drive force transmitting mechanism for driving the discharging member to rotate, and a discharge control unit for controlling the drive force transmitting mechanism when the sheet passes the discharging member so as to temporarily delay a time taken for sheet discharging by the discharging member.

Abstract: An image forming apparatus includes a plurality of image forming devices for forming respective monochromatic images in accordance with input image signals. The apparatus is operable in a first mode for forming a multi-color image by the plurality of image forming devices at a first image formation speed and in a second mode for forming a multi-color image by the plurality of image forming devices at a second image formation speed. The apparatus also includes an execution device for executing, for respective image formation speeds, calibrating operations for correcting image density levels of output images formed by the image forming devices in response to image density levels of the input image signals.

Abstract: The image forming apparatus of the present invention having a developer containing section and a developer remaining amount detecting member, and capable of forming an image at any of a plurality of printing speeds, has a configuration in which the averaging method of the developer remaining amount by the developer remaining amount detecting member is changed in response to the printing speed. The invention thus provides an image forming apparatus having a plurality of printing speeds, which permits successive detection of the remaining amount of developer at a high accuracy in response to the printing speed.

Abstract: An image forming apparatus forms a latent image on the basis of a signal outputted at a constant time interval, and develops the latent image on a sheet in an image forming section. A resist roller pair arranged upstream of the image forming section and able to change a conveying speed re-feeds the sheet after the sheet is stopped for a predetermined time. A controller starts the conveyance of the sheet at a speed higher than an image forming speed, controls the speed of the resist roller pair so as to be equal to the image forming speed at a position before a predetermined distance from the image forming section and sets the conveying speed at a high speed conveying time in the resist roller pair so as to be equal to the image forming speed at the position before the predetermined distance from the image forming section.

Abstract: A CPU 111 drives an intermediate transfer belt at a first speed in a normal mode, but drives the intermediate transfer belt at the first speed in a low speed mode at least until the end of forming a toner image performed by a developer part 20, reduces the speed from the first speed to a second speed after the end of forming the toner image and then maintains the second speed at least until the end of secondary transfer. In the intermediate transfer belt, there are a transfer area, in which primary transfer of a toner image is possible, and a transfer protection area in which primary transfer of a toner image is prohibited and which is provided along a direction of rotation axis. In the low speed mode, the CPU 111 controls image forming so that a toner image will be primarily transferred onto such a portion of the transfer area which is close to the transfer protection area and on the upstream side of the intermediate transfer medium along a direction of rotational driving.

Abstract: A sheet transferring apparatus for use in an image forming apparatus including a sheet transferring mechanism and a controller. The sheet transferring mechanism transfers a recording sheet at a transfer speed to an image forming mechanism in the image forming apparatus. The controller determines the transfer speed based on a transfer speed used for an immediately previous recording sheet.

Abstract: An image forming apparatus is provide which includes an ADU that can sustain productivity per unit of time, without controlling the operation of registration rollers at fixed intervals determined by CPM that leads to temporary stopping of paper. During non-stacked circulatory conveyance for forming images on both sides of a sheet of paper, the position or the timing is corrected at which the paper is accelerated and/or decelerated in a circulatory conveyance path, whereby the image forming apparatus does not control the operation of registration rollers at fixed intervals determined by CPM when forming another image on a back side of the paper.

Abstract: An image forming apparatus of the present invention includes an image carrier for carrying a toner image thereon while being driven to rotate. A conveyor conveys a recording medium, to which the toner image is to be transferred from the image carrier, to an image transfer position. An image carrier controller controls the linear velocity of the image carrier in rotation. A conveyance controller controls the linear velocity of the recording medium being conveyed by the conveyor. A main controller controls the image carrier controller and conveyance controller such that the mean linear velocity of the image carrier and that of the recording medium are different from each other.

Abstract: An image forming device having a sheet conveying path extending from a feeder unit to an image forming unit. A convey roller positioned downstream of the sheet supply roller is rotated at a peripheral speed V3. Additional convey roller positioned downstream of the first convey roller is rotated at a peripheral speed V2 lower than V3. A register roller positioned downstream of the second convey roller is rotated at a peripheral speed V1 lower than V2. A transfer roller of the image forming unit is rotated at a peripheral speed V0 lower than V1. Each convey roller, the register roller, the sheet supply roller is connected to each clutch. Sheet sensors are provided between neighboring rollers for detecting a leading edge of the sheet. Upon detection of the leading edge, the roller positioned immediately upstream of the one of the sensors is shifted to its non-driving state.

Abstract: A voltage generated when a predetermined electric current is applied to a transfer roller is measured, and a sheet transport speed is determined based on the measured voltage, a sheet type, and a sheet width. The transport speed is reduced when current leakage tends to occur due to a narrow sheet width or low resistance in the transfer roller, so that the electric charge per unit area applied to the sheet is maintained constant without increasing a transfer bias to be applied to the transfer roller.

Abstract: An image forming apparatus has a main unit including a printing section for executing printing on a paper sheet and a first conveyance section for conveying a paper sheet at a set speed, and a peripheral unit connected to the main unit and having a second conveyance section for conveying a paper sheet at a predetermined speed. The apparatus includes a storage for storing the conveyance speed of the second conveyance section, and the upper limit of the current used to drive a motor in the second conveyance section, the conveyance speed and the upper limit being varied in accordance with the type of main unit and stored in association with the upper limit, a type setting section for setting the type of main unit, and a setting section for setting, in accordance with the set type, the conveyance speed of the second conveyance section and the upper limit of the current used to drive the motor.

Abstract: An image-production system includes a marking engine. The image-forming production system may also include an inserter. The marking engine includes a marking engine controller, a speed adjust system and a registration system. The registration system aligns sheets going to an imaging unit. The speed adjust system controller includes a speed adjust system controller. When at least one sheet approaches the speed adjust system, the marking engine controller transmits a synch pulse signal to the speed adjust system controller. The speed adjust system transmits a signal to the speed adjust system controller of the arrival time of the at least one sheet. The speed adjust system compares the measured arrival time with the synch pulse signal to adjust a speed and timing of the sheet before the sheet is transferred to the registration system.

Abstract: In an image forming apparatus which has a primary sheet feeder, a secondary sheet feeder for conveying a recording sheet which is fed from the primary sheet feeder to an image forming position in timed relationship with image formation, and a controller for controlling the primary sheet feeder and the secondary sheet feeder, the controller selects long and short two kind of sheet feed intervals according to a detection signal of a recording sheet detector provided upstream of the secondary sheet feeder.

Abstract: An image forming section forms images, which are transferred onto a primary medium. A medium cassette holds a stack of print medium. A remaining-medium detector detects the number of pages of remaining print medium held in the medium cassette. The image on the primary medium are transferred onto a print medium fed from the medium cassette. A controller changes a timing at which the image forming section forms the images, the timing being changed in accordance with the number of pages of remaining print medium. The timing is changed in such a way that the images are formed at greater distance intervals on the primary medium when the number of pages of the medium cassette in the medium cassette is equal to or less than a reference value than when the number of pages of the medium cassette in the medium cassette is more than the reference value.

Abstract: There is provided an image forming apparatus that can suppress the formation of creases when forming images on both surfaces of a sheet and can greatly reduce the incidence of unprinted areas. The image forming apparatus has a sheet stacking section in which sheets are stacked, a sheet conveying section that conveys a sheet, an image forming section that forms an image on the sheet while the sheet is conveyed, a re-conveying section that again conveys the sheet with the image formed on a first surface thereof to the image forming section, and a sheet feeding section that feeds a sheet from the sheet stacking section or the re-conveying section to the image forming section.

Abstract: An image forming apparatus includes an image bearing member, an electrifying member for electrifying the image bearing member; an image forming member for forming an image on the image bearing member electrified by the electrifying member; a conveying member for making a recording material, which has been conveyed from a recording material receiving portion held in waiting and waiting then conveying the image on the image bearing member to a transfer portion for transferring the image onto the recording material; and a control member controls a start timing of electrification by the electrifying member in accordance with a start timing of a conveyance of the recording material by the conveying member.

Abstract: An image forming apparatus has a main unit including a printing section for executing printing on a paper sheet and a first conveyance section for conveying a paper sheet at a set speed, and a peripheral unit connected to the main unit and having a second conveyance section for conveying a paper sheet at a predetermined speed. The apparatus includes a storage for storing the conveyance speed of the second conveyance section, and the upper limit of the current used to drive a motor in the second conveyance section, the conveyance speed and the upper limit being varied in accordance with the type of main unit and stored in association with the upper limit, a type setting section for setting the type of main unit, and a setting section for setting, in accordance with the set type, the conveyance speed of the second conveyance section and the upper limit.

Abstract: A main CPU effects a control to decrease a reverse convey speed of reverse conveyance by a reverse roller pair when a low-noise mode is set, a control to decrease, where necessary, a reverse convey speed of reverse conveyance by an ADU reverse roller pair, and a control to set a sheet at an optimal reverse position when a convey speed for a fixing device, the reverse roller pair or the ADU reverse roller pair is varied.

Abstract: An image bearing member life detecting method capable of accurately detecting that the life of an image bearing member has expired or will expire soon, an image forming apparatus using the method, and a cartridge detachably attachable to the image forming apparatus, are provided. An image bearing member damage index number D representing the consumption degree of an image bearing member is calculated on the basis of an applying period under each condition of an electrostatic charge bias applied to an electrostatic charging portion for forming an electrostatic latent image on the image bearing member, and/or the contact period of a developing portion for developing the electrostatic latent image on the image bearing member. When the process speed is switched, the calculation method is switched in accordance with the process speed, and the image bearing member damage index number D is calculated.

Abstract: An apparatus and method for advancing a receiver into registered relationship with a moving image-bearing member. A motor is provided that is responsive to motor drive pulses. A drive member engages the receiver, and a drive coupling connects the drive member and the motor. An encoder generates encoder pulses that correspond with movement of the image-bearing member. A pulse generator generates motor drive pulses in response to the encoder pulses to accelerate the receiver to a speed approximately equal to the speed of the image-bearing member speed. A timer determines an amount of delay time between detection of the receiver by an in-track sensor and the beginning of a subsequent movement of the motor. A delay mechanism delays the acceleration of the receiver to the image-bearing member speed by the amount of delay time.

Abstract: A controller outputs a PRE CPF-N signal and a CPF-N signal following the PRE CPF-N signal to an electrophotographic printer. The electrophotographic printer 1 starts a predetermined preparation process in response to the PRE CPF-N signal, and starts irradiation in response to the CPF-N signal. The preparation process completes by the time of when a toner image for a first page formed on a photosensitive drum reaches a transfer point where the toner image is transferred onto a recording medium.

Abstract: An image forming apparatus of the present invention includes an intermediate image transfer belt to which a toner image is to be transferred from an image carrier, an image transferring device for transferring the toner image from the intermediate image transfer belt to a sheet, and a fixing device for fixing the toner image on the sheet. When the length of the sheet in the direction of conveyance is smaller than a distance between the image transferring device and the fixing device, a matching circuit varies only the speeds of the image transferring device and fixing device, but does not vary the speed of a device that executes a step preceding the image transfer step. The matching device then sets an interval between consecutive sheets matching with the varied speeds of the image transferring device and fixing device, thereby matching opposite sides with respect to the image transfer step to each other as to the number of sheets to be conveyed.

Abstract: An image forming apparatus has a sheet material conveying system for conveying the sheet material to an image forming device and has an image formation driving source for driving the image forming device.

Abstract: An image forming apparatus is provide which comprises an ADU that can sustain productivity per unit of time, without controlling the operation of registration rollers at fixed intervals determined by CPM that leads to temporary stopping of paper. During non-stacked circulatory conveyance for forming images on both sides of a sheet of paper, the position or the timing is corrected at which the paper is accelerated and/or decelerated in a circulatory conveyance path, whereby the image forming apparatus does not control the operation of registration rollers at fixed intervals determined by CPM when forming another image on a back side of the paper.

Abstract: The present invention relates to a sheet conveying apparatus comprising a first conveying means for conveying a sheet, a second conveying means for conveying a sheet in merging with the first conveying means and a sheet merging overlapping means. At a junction between the first and second conveying means, the sheet merging overlapping means overlaps the sheet conveyed by the first conveying means with the sheet conveyed by the second conveying means in a sheet conveyance direction.

Abstract: An image forming apparatus forms a latent image on the basis of a signal outputted at a constant time interval, and also forms the image on a sheet by developing the latent image in an image forming section. In the image forming apparatus, a resist roller pair arranged on the upstream side of the image forming section and able to change a conveying speed re-feeds the sheet after the sheet is stopped for a predetermined time. A controller starts the conveyance of the sheet re-fed by the resist roller pair where a speed higher than an image forming speed in the image forming section, and controls the speed of the resist roller pair so as to be equal to the image forming speed at a position before a predetermined distance from the image forming section. The controller sets the conveying speed at a high speed conveying time in the resist roller pair so as to be equal to the image forming speed at the position before the predetermined distance from the image forming section.

Abstract: An image forming apparatus includes, a rotatable image carrier, a writing exposure device to write the image and form a latent image in the rotatable image carrier, a developing device to form a toner image, a registration roller to convey a transfer sheet to an image transfer area where the toner image is transferred from the image carrier onto the transfer sheet, and a fixing roller to heat and fix the toner image, wherein when the length of a transfer sheet is longer than the length of the transfer sheet path between the registration roller and the fixing roller, according to the size of the transfer sheet, the controller changes and controls the relative rotating speed of the registration roller to a rotating speed of the fixing roller, and one of a rotating speed of the rotatable image carrier and a writing speed of the image.

Abstract: An image forming device having a sheet conveying path extending from a feeder unit to an image forming unit. In the feeder unit, a sheet supply roller is rotated at a peripheral speed Vs. A convey roller positioned immediately downstream of the sheet supply roller is rotated at a peripheral speed V3 lower than Vs. Additional convey roller positioned immediately downstream of the first convey roller is rotated at a peripheral sped V2 lower than V3. A register roller positioned downstream of the second convey roller is rotated at a peripheral speed V1 lower than V2. A transfer roller of the image forming unit is rotated at a peripheral speed V0 lower than V1. Each convey roller, the register roller, the sheet supply roller is connected to each clutch. Sheet sensors are provided each positioned between neighboring rollers for detecting a leading edge of the sheet.

Abstract: An image-forming apparatus includes a photosensitive drum, scuff rollers to move recording paper along a transfer path, a tractor disposed upstream from the scuff rollers, back-tension rollers disposed upstream from the tractor to exert a tension on the recording paper, and a speed controller to adjust the transfer speed of the recording paper. The speed controller makes greater the circumferential speed of the back-tension rollers than the transfer speed by the tractor during a period after the recording paper is started to move along the transfer path and before image-printing is begun.

Abstract: An image forming apparatus of the present invention includes an image carrier for carrying a toner image thereon while being driven to rotate. A conveyor conveys a recording medium, to which the toner image is to be transferred from the image carrier, to an image transfer position. An image carrier controller controls the linear velocity of the image carrier in rotation. A conveyance controller controls the linear velocity of the recording medium being conveyed by the conveyor. A main controller controls the image carrier controller and conveyance controller such that the mean linear velocity of the image carrier and that of the recording medium are different from each other.

Abstract: An image forming apparatus of the present invention includes an image carrier for carrying a toner image thereon while being driven to rotate. A conveyor conveys a recording medium, to which the toner image is to be transferred from the image carrier, to an image transfer position. An image carrier controller controls the linear velocity of the image carrier in rotation. A conveyance controller controls the linear velocity of the recording medium being conveyed by the conveyor. A main controller controls the image carrier controller and conveyance controller such that the mean linear velocity of the image carrier and that of the recording medium are different from each other.

Abstract: A document-handling apparatus and method for transporting documents along a document feed path from an upstream end to a downstream end. The apparatus includes at least one document-handling subassembly along the document feed path for singulating the documents, controlling gaps between the documents, and conveying the documents toward the downstream end; a sensor mounted along the document feed path for sensing the positions of the documents and for generating position signals based on the document positions; and a control apparatus for receiving the position signals and for controlling the velocity and acceleration of the document-handling subassembly so as to regulate the size of the document gaps and to maximize document throughput. The document-handling subassemblies can include a stack advance mechanism, an input feeder, one or more singulators, and one or more output feeders. A trap can also be included to stop a document along the feed path. The apparatus can operate at accelerations as low as 0.

Abstract: The present invention relates to a method for improving a print quality of an image forming apparatus. The invention provides a method for improving the print quality of an image forming apparatus capable of preventing the deterioration of the print image according to the change of the environment condition around the image forming apparatus by controlling the print speed of the image forming apparatus in case that the environment condition is at a low temperature and low humidity when checked at the non-image stage of the apparatus. According to the present invention, it is checked whether or not the environment condition around the image forming apparatus is at a low temperature and low humidity at a non-image period prior to the beginning of print after the print data received externally are stored at a memory of the image forming apparatus.

Abstract: An image forming apparatus includes an image forming portion for forming an image on a sheet. A separating and feeding portion feeds sheets stacked on a sheet supporting portion one-by-one toward the image forming portion. A sheet conveying portion conveys the sheets fed by the separating and feeding portion. Registration rollers of a variable rotating speed are disposed upstream of the image forming portion with respect to a sheet conveying direction. A sheet conveyance controlling portion causes the registration rollers to effect the conveyance of the sheets at a speed higher than the image forming speed in the image forming portion. Thereafter, the registration rollers are decelerated so as to assume substantially the same speed as the image forming speed at a timing earlier than a latest image forming timing in the image forming portion.

Abstract: An image forming apparatus which can suppress the occurrence of noises without reducing productivity. Sheet transporting units are provided in a paper supply transport section for transporting a sheet to an image forming section, and in a paper ejection transport section for transporting the sheet, on which an image has been formed in the image forming section, to a paper ejection section. When an image is formed on a predetermined sheet, a speed control unit controls a sheet transport speed of at least one of the sheet transporting units provided in the paper supply transport section and the paper ejection transport section to be higher than that in the image forming section.

Abstract: A method for calculating a print medium pick time for an imaging apparatus that transports media at variable speeds along a media path, includes the steps of providing a staging process for varying a transport velocity of a media sheet before transferring an image to the media sheet at the image transfer location, the staging process being used for positioning a top writing line margin of the media sheet in relation to the image at the image transfer location; determining a time period t1 corresponding to a time when a pick motor is started to pick the media sheet to a time when the staging process is started; determining a derived time period t2 representative of a normalized time from when the staging process is started to a time when a media path sensor senses the media sheet; and determining a compensated calculated pick time for the media sheet by summing the time period t1 with the time period t2.

Abstract: An image forming apparatus such as a printer and a copier has rotating devices such as a drum and a press roller to print an image on a paper sheet while rotating and a paper-transporting mechanism having guide rollers and timing rollers for transporting a paper sheet to these rotary devices, controlled by a control device such that irregularities in the printed images due to fluctuations in the speed of transportation of the paper sheets. The guide rollers may be operated to transport the paper sheet at a faster speed than the paper sheet is transported by the rotary devices such that the paper sheet becomes bent before being delivered to the rotary devices to be printed on. The control may be such that the guide rollers transport the paper sheet while the timing rollers downstream is released from the transportation of paper sheets. The control device may also operate so as to stop the guide rollers when the paper sheet comes to a position where the rotary devices can start transporting it.