Abstract: An image forming apparatus that can detect a leading edge of a tabbed sheet after skew correction with high accuracy and without increasing a size of the apparatus. A transfer unit transfers a toner image to the sheet, the skew of which having been corrected based on a detection result of a first skew detection unit, while the toner image is controlled to be synchronized with the sheet based on the detection result of the first skew detection unit and a detection result of a second skew detection unit.

Abstract: Sheet registration method and system includes transporting a sheet including a leading edge and a trailing edge between a first and second sensor. The first and second sensors each have a linear sensing area with a longitudinal axis aligned at a non-zero angle to each other. The first and second sensors are adapted to identify positions of the leading edge and the trailing edge. An alignment of the sheet is adjusted responsive to a sheet length determined using the output from the first and second sensors.

Abstract: The skew feeding amount of a sheet front end is calculated according to the difference between timings when activation sensors detect the sheet front end, and the skew feeding amount of the sheet side edge is calculated according to the difference between side edge positions of the sheet detected by the first side registration detection sensor or the second side registration detection sensor. Further, whether a sheet is a rectangular sheet or a non-rectangular sheet is determined before skew feeding of the sheet is corrected, and, when the sheet is determined to be a rectangular sheet, the skew feeding correcting portion is controlled based on one of the sheet side edge skew feeding amount and sheet front end skew feeding amount and the skew feeding correcting portion is controlled based on the sheet side edge skew feeding amount when the sheet is determined to be a non-rectangular sheet.

Abstract: A sheet reversing apparatus including: a right angle reversing conveyance section which reverses front/back sides of a sheet while changing a conveyance direction of the sheet, being conveyed in a first conveyance direction, to a second conveyance direction perpendicular to the first conveyance direction; a sheet skew sensor which detects a sheet skew of the sheet being conveyed by the right angle reversing conveyance section; and a sheet skew correction mechanism which corrects the sheet skew of the sheet while the sheet is being conveyed by the right angle reversing conveyance section.

Abstract: Apparatus and a method aligns and orients a moving article, such as a sheet or a carton blank during processing of the sheet/carton blank, relative to its intended path of travel through a conveyor-type assembly machine. In one embodiment, a pair of sensors detect passage of respective laterally spaced leading edge portions of the moving sheet and provide inputs to a controller which, in turn, provides an appropriate signal to one of a pair of spaced sheet-gripping rollers in contact with the respective laterally spaced portions of the sheet for aligning, or squaring, the sheet's leading edge relative to its intended path through the assembly machine. In another embodiment, a single sensor detects a linear lateral edge of the sheet and a single drive element orients and aligns the sheet's edge so that it is coincident with and parallel to a linear target line defining the intended path of travel.

Abstract: A sheet supplying unit having no need to place a great many skew sensors and enabling printing apparatus to simplify structure and to reduce cost. The sheet supplying unit moves a skew sensor to a most left sensor position in which the table sensor detected that the print medium exists, detects the upper edge of print medium, and executes a skew detection; in the case that the print medium is narrow, moves a skew sensor, detects the upper edge of print medium, and executes a skew detection; in the case that a position of skew sensor does not place at a position keeping a predetermined margin at the inside of the print medium, moves skew sensor to the inside of the print medium and executes again an inclination detection; or according to print medium width and skew sensor width, changes a skew judgment quantity.

Abstract: A recording medium conveyor includes a first conveyance part conveying a recording medium; a second conveyance part conveying the conveyed recording medium toward a transfer position; a detection part detecting the position of the recording medium conveyed by the second conveyance part; a position error detection part detecting a position error between the transfer position and a position at which there is to be the recording medium when an image reaches the transfer position; a position error storage part storing the detected position errors; a steady-state position error calculation part calculating a steady-state position error from the stored position errors; a first control part controlling the conveyance speed of the first conveyance part to reduce the steady-state position error; and a second control part controlling the conveyance speed of the second conveyance part to reduce the detected position error, with the steady-state position error being reduced.

Abstract: A sheet conveyance device that is capable of appropriately correcting a position of a sheet in the sheet width direction with respect to an image transferred thereon. A shift mechanism shifts a sheet conveyed in a sheet width direction perpendicular to a sheet conveyance direction. A first sensor detects one side edge of the sheet in the sheet width direction. A second sensor detects the other side edge of the sheet in the sheet width direction. A control unit drives the shift mechanism so that the center of the sheet in the sheet width direction is coincident with a predetermined target position based on the gap of the first and second sensors, detection timing of the one side edge by the first sensor, detection timing of the other side edged by the second sensor, and a predetermined standard value of sheet width.

Abstract: An image recording apparatus includes: a sheet supplier configured to supply a recording medium; a first conveyor configured to convey the recording medium supplied from the sheet supplier in a conveying direction; a recording portion configured to record an image on the recording medium conveyed by the first conveyor; and a controller configured to detect an orientation of the recording medium with respect to the conveying direction while the recording medium is conveyed and change a conveying speed of the recording medium conveyed by the first conveyor depending on the detected orientation of the recording medium.

Abstract: A device for measuring a length of a recoding material, includes: a rotating body that rotates in contact with a recording material which is transported; a length measuring unit that measures a length of the recording material based on a rotation of the rotating unit; a detecting unit that detects at least one of a rotation and an oblique advance of the recording material; and a correcting unit that corrects a value measured by the length measuring unit based on an output of the detecting unit.

Abstract: A method and system feeds sheets through a media path in a process direction and moves a laterally movable sheet registration carriage (positioned within the media path) in a lateral direction perpendicular to the process direction. It determines the lateral error of the sheets within the media path before the sheets enter the sheet registration carriage, using first sensors positioned within the media path. This allows the sheet registration carriage to be moved to a variable lateral starting position (as opposed to a consistent reset position or centered reset position) before the sheets enter the sheet registration carriage based on the error of the sheets as determined by the first sensors. The error can be the amount of lateral error, or simply can be a classification of lateral error (right error, left error, etc.).

Abstract: A reference member which regulates a position of one side end of a sheet along the sheet conveying direction is provided at one side of a sheet conveying path in the width direction so as to follow the sheet conveying direction and to be rotatable about its downstream end portion in the sheet conveying direction. Then, one side end of the sheet is skew-conveyed toward the reference member by a plurality of pair of skew-conveying rollers which is arranged in the sheet conveying path along the sheet conveying direction. Then, when forming an image on both faces of the sheet, a control portion rotates the reference member so that the sheet is displaced to the center side in the sheet conveying path compared to the case of forming an image on one face of the sheet.

Abstract: After a sheet has once passed through a punching position, a conveyance roller pair conveys the sheet backward to the punching position. A lateral registration detection sensor detects a side edge position of the sheet in a width direction. When a sheet processing apparatus corrects the side edge position of the sheet by controlling a shift unit for moving the sheet in the width direction so as to correct the side edge position of the sheet, the sheet processing apparatus sets a shifting amount of the sheet to a value that is a predetermined amount greater than a shifting amount required to correct the side edge position of the sheet according to the side edge position of the sheet detected by the lateral registration detection sensor. After the sheet has passed through the die hole the sheet processing apparatus sets the shifting amount to the required value.

Abstract: A sheet conveying apparatus in which a sheet is abutted on a stopped registration roller to correct skew feeding, including: a sheet detecting portion, a first stepping motor and a second stepping motor. The conveying roller is controlled to tentatively stop the sheet, the conveying roller is driven prior to the start of the drive of the registration roller, the registration roller is driven after a loop of a predetermined amount is formed in the sheet, the conveying roller is driven at a sheet conveying speed that is equal to or lower than a sheet conveying speed of a self-start frequency when the conveying roller forms the loop in the sheet, rotation of the first stepping motor being able to be started at the self-start frequency, and acceleration of the registration roller and acceleration of the conveying roller are started after the loop of the predetermined amount is formed.

Abstract: A disclosed sheet aligning device includes a sheet conveyance path; a detecting unit configured to detect a side edge of a sheet being conveyed in the sheet conveyance path; a stopper provided on an upstream side of the detecting unit and configured to open/close in such a manner as to allow/prevent passage of the sheet through the sheet conveyance path and to position a leading edge of the sheet being conveyed in the sheet conveyance path; a first conveying unit provided on an upstream side of the stopper, the first conveying unit including a pair of first rollers configured to come in contact with/separate from each other; a second conveying unit provided on an upstream side of the first conveying unit, the second conveying unit including a pair of second rollers configured to come in contact with/separate from each other; and a horizontal movement unit configured to move the pair of first rollers in an axial direction of the first rollers based on a detection result output by the detecting unit.

Abstract: A sheet conveying apparatus includes a conveying path for conveying a sheet, an optical displacement sensor that detects displacement of the sheet, and a calculating unit that calculates a movement index value indicating moving distances of the sheet in a conveying direction and a direction perpendicular thereto based on an output from the optical displacement sensor. The optical displacement sensor includes a plurality of light receiving elements arranged in a matrix array. A row alignment direction and a column alignment direction of the light receiving elements are tilted with respect to the conveying direction.

Abstract: A skew correction device includes a first conveying unit arranged in a sheet conveying path; a second conveying unit arranged downstream of the first conveying unit in a conveying direction of a sheet; and a skew correction unit. When the sheet is unfolded paper, the skew correction unit performs a first skew correction that corrects for the skew of the sheet so that a leading edge of the sheet conveyed by the first conveying unit abuts on the second conveying unit that is stopped. When the sheet is fold paper, the skew correction unit performs a second skew correction that corrects for the skew of the sheet so that a leading edge of the sheet conveyed by the first conveying unit abuts the second conveying unit and the second conveying unit is driven in a reverse direction to the conveying direction at a predetermined operational timing.

Abstract: A sheet conveying apparatus including: a sheet conveying unit; an upstream side guiding member that forms an upstream side conveying route of a sheet; a downstream side guiding member that forms a downstream side conveying route of the sheet; an upstream side detection unit; and a downstream side detection unit, wherein a detection position of the sheet for the upstream side detection unit is set between the sheet conveying unit and a position where the sheet is in contact with the upstream side guiding member, and a detection position of the sheet for the downstream side detection unit is set between the sheet conveying unit and a position where the sheet is in contact with the downstream side guiding member.

Abstract: A sheet processing apparatus capable of high-speed and accurate detection of a lateral displacement and a skew of a sheet. A motor laterally shifts the sensors during sheet conveyance by a conveying motor, to determine first and second positions of the sheet lateral edge detected respectively by first and second sensors. A finisher controller determines a third position of the lateral edge of the sheet closer to a sheet trailing edge, based on the first and second positions and an amount of conveyance of the sheet from when the first position is detected to when the second position is detected. A lateral displacement of the sheet is corrected by laterally shifting the sheet according to the third position of the sheet lateral edge.

Abstract: A sheet processing system capable of performing lateral shift correction of a sheet in an upstream sheet processing apparatus based on an amount of lateral shift to be caused by conveying thereof into a downstream sheet processing apparatus. A side edge sensor of a stacker detects a lateral shift amount of a sheet conveyed into the stacker. A stacker controller corrects lateral shift of the sheet by a shift unit. A side edge sensor of a finisher disposed downstream of the stacker detects a lateral shift amount of a sheet conveyed into the finisher. The finisher sends the detected lateral shift amount to the stacker. The stacker receives the lateral shift amount from the finisher, and the stacker controller corrects lateral shift of subsequent sheets based on both the lateral shift amount detected in the stacker and the lateral shift amount sent from the finisher.

Abstract: An image forming apparatus acquires sheet information indicating paper weight or the like of a transported sheet of paper. The apparatus also has a control portion and shifts a reference position which has been previously set to a direction orthogonal to a transporting direction of the sheet of paper based on the paper weight or the like of the transported sheet of paper. A deviation sensor detects a deviation of the sheet of paper with regard to the shifted reference position along the direction orthogonal to the transporting direction of the sheet of paper. A sheet shift portion shifts the sheet of paper to the shifted reference position based on the deviation detected by the deviation sensor.

Abstract: Accurate sheet leading edge registration system and method including a first and second nip assembly, a first sheet leading edge sensor and a controller. The first and second nip assemblies being spaced apart from one another. The first sheet leading edge sensor capable of detecting an arrival of a leading edge of a sheet at a point in the process direction. The arrival being associated with engagement of the first and second nip assemblies with the sheet. The controller capable of imparting a rotational skew velocity to the sheet using the first and second nip assemblies. A center of rotation of the skew velocity being offset laterally from a center of the sheet leading edge and being coincident with a lateral position of a virtual point, the virtual point lateral position being offset from a lateral position of the first sheet leading edge sensor.

Abstract: This paper feeder brings the uppermost paper sheet of a plurality of stacked paper sheets into contact with paper feed rollers and feeds out the paper sheet in a paper feeding direction by the drive thereof. Side fences for guiding both side edges of the paper sheet on a paper feeding table are provided with a pair of blowing units for blowing air to both side edges of the paper sheet, whose air quantity can be controlled independently of each other. When skewing occurs, the blowing units are controlled to blow a larger quantity of air to the paper side edge having larger friction against a lower paper sheet as compared with the quantity of air to the other paper side edge. In paper feeding, problems such as skewing, multi-feeding and idle feeding can be addressed.

Abstract: There are provided a sheet stacking apparatus capable of stably stacking a large number of sheets and an image forming apparatus. The sheet stacking apparatus configured to stack sheets includes a plurality of discharge units disposed to an apparatus main body in a vertical direction and configured to discharge sheets, a plurality of sheet stacking units disposed to be independently elevatable on a side surface of the apparatus main body corresponding respectively to the plurality of discharge units and configured to stack thereon the sheets discharged from the discharge units, and an alignment unit disposed between the plurality of sheet stacking units and configured to sequentially align a position in a width direction perpendicular to a discharging direction of the sheets stacked on a lower sheet stacking unit among the plurality of sheet stacking units.

Abstract: A sheet conveying apparatus and an image forming apparatus capable of high-precision sheet position correction is provided. At the time of moving a pair of registration rollers in the width direction, a data storage portion stores the deficiency quantity of a motion quantity in the width direction and an inclination quantity incurred in the pair of registration rollers with respect to the sheet conveying direction. At the time of correcting a skew feeding of a sheet by a pair of skew feeding correction rollers, a controller adjusts a skew feeding quantity detected by an activation sensor by the inclination quantity stored in the data storage portion, and at the time of moving the pair of registration rollers in the width direction, the controller adjusts the motion quantity by the deficiency quantity of the motion quantity stored in the data storage portion.

Abstract: The skew feeding amount of a sheet front end is calculated according to the difference between timings when activation sensors detect the sheet front end, and the skew feeding amount of the sheet side edge is calculated according to the difference between side edge positions of the sheet detected by the first side registration detection sensor or the second side registration detection sensor. Further, whether a sheet is a rectangular sheet or a non-rectangular sheet is determined before skew feeding of the sheet is corrected, and, when the sheet is determined to be a rectangular sheet, the skew feeding correcting portion is controlled based on one of the sheet side edge skew feeding amount and sheet front end skew feeding amount and the skew feeding correcting portion is controlled based on the sheet side edge skew feeding amount when the sheet is determined to be a non-rectangular sheet.

Abstract: A label sheet conveyance device is provided to more accurately automatically detect seams between label sheets in a label printer. Using a first threshold value that is set according to the mode of sensor output values for detecting the sheet portion between labels, and a second threshold value that is greater than the first threshold value for detecting holes in the label sheet, a label printer determines a sheet position where the sensor output value is equal to each threshold value. If a sheet position equal to the second threshold value is detected, the center of that sheet position is identified as the seam position. If a sheet position equal to the second threshold value is not identified and a sheet position equal to the first threshold value is identified, the center of that sheet position is identified as the seam position.

Abstract: In an apparatus for correcting a position of a sheet which is transported in the grip of grippers on a feed drum of a sheet processing machine, in particular a sheetfed rotary printing press, provision is made for a gripper device of the drum to be mounted in independently rotatable arranged supports and for it to be possible for each support to be driven by a step-up gear mechanism.

Abstract: A sheet conveyance apparatus includes a control unit which controls the operation of a registration roller shift motor so as to perform positional deviation correction based on the detection result of a contact image sensor (CIS) configured to detect positional deviation in the width direction of a sheet. When the amount by which the registration roller shift motor moves the registration roller in the width direction exceeds an upper limit value, the control unit limits the movement amount by which the registration roller shift motor moves the registration roller in the width direction.

Abstract: A control system and method for a sheet registration device including a general unit which determines desired contact point velocities for moving a sheet along a reference trajectory. The contact point velocity determination is independent of the sheet registration device. A specific unit is operably connected to the general unit. The specific unit determines registration device specific operating parameters for controlling registration device actuators to move the sheet along the reference trajectory.

Abstract: An image forming unit may include a capability of determining whether paper conveyed through the unit is bending. In some embodiments, an amount of bending of the conveyed paper may be determined. An embodiment of an image forming apparatus may include a paper feeding unit, an image forming unit, a skew correcting roller pair, a rotary member pair, sensors, signal processing units, and a control unit. A rotary member pair may convey a sheet to the skew correcting roller pair. Sensors may be disposed at various positions along the conveying path. In some embodiments, the sensors may include transmitting units and/or receiving units. These units may be positioned such that a conveyed sheet passes through therebetween. Signal processing units and control units may allow for the determination of the bending of conveyed sheets.

Abstract: An image forming apparatus includes a main body, a sheet conveyance apparatus, and a control unit. The main body includes an image forming unit to form an image on a sheet. The sheet conveyance apparatus and the main body are detachable from each other and the sheet conveyance apparatus may convey the sheet to the image forming unit. The sheet conveyance apparatus includes a sheet conveyance path through which the sheet passes and a detection unit. The detection unit includes light emitting and receiving units that transmit light across the sheet conveyance path therebetween. The detection unit detects a reference and an edge position of the conveyed sheet in a width direction of the sheet orthogonal to a sheet conveyance direction. The control unit determines a position of the sheet based on detections of the reference and the edge position of the conveyed sheet by the detection unit.

Abstract: After a sheet has once passed through a punching position where punching processing is performed, a conveyance roller pair conveys the sheet backward to the punching position. A lateral registration detection sensor detects a side edge position of the sheet in a width direction. When a sheet processing apparatus corrects the side edge position of the sheet by controlling a shift unit configured to move the sheet in the width direction so as to correct the side edge position of the sheet, the sheet processing apparatus sets a shifting amount of the sheet to a value that is a predetermined amount greater than a shifting amount required to correct the side edge position of the sheet according to the side edge position of the sheet detected by the lateral registration detection sensor. After the sheet has passed through the die hole in the backward movement toward the punching position, the sheet processing apparatus sets the shifting amount to the required value.

Abstract: The present invention provides a sheet conveying apparatus and an image forming apparatus capable of preventing occurrence of skew feeding when correcting sheet lateral deviation. A pair of lateral-shift correcting rollers 305 to correct positional deviation in the sheet width direction based on positional deviation quantity detected by a lateral-registration detection sensor 204c is controlled after controlling a skew feeding correcting roller 203 so as to correct sheet skew feeding based on skew-feeding quantity at a sheet leading edge detected by skew-feeding detection sensors 204a and 204b. Then, skew-feeding quantity of the sheet leading edge to be detected by the skew-feeding detection sensors 204a and 204b for correcting skew feeding of the next sheet is adjusted with skew-feeding quantity at the sheet trailing edge detected by the lateral-registration detection sensor 204c after positional deviation in the sheet width direction is corrected.

Abstract: In a sheet conveying apparatus a first shape information that expresses at least a part of the outer shape of a sheet. An obtaining unit obtains second shape information that expresses at least the part of the outer shape of the sheet. A correction amount computing unit computes a correction amount of the sheet for correcting an image to be formed on the sheet and/or correcting the position and/or orientation of the sheet based on the first shape information and the second shape information. A correction amount computing unit computes a correction amount for correcting the position and/or orientation of the sheet relative to the conveying direction from the computed skew amount. A position and/or orientation correction unit corrects an image to be formed on the sheet and/or the position and/or orientation of the sheet, according to the computed correction amount.

Abstract: A sheet alignment device includes a first alignment arm, a second alignment arm, a first sensor and a controller. The first alignment arm includes a first blocking piece and a second blocking piece. During the sheet-aligning action of each sheet, the first alignment arm is moved for a preset distance from a standby position. Then, the first alignment arm is moved back to the standby position, and a waiting time is required to introduce a next sheet into the sheet placement tray. When the first sensor is no longer interrupted by the second blocking piece of the first alignment arm, the controller starts to calculate the moving distance of the first alignment arm. Since the moving distance of the first alignment arm is calculated at the same start point during the sheet-aligning action of each sheet is performed, the possibility of resulting in the moving distance error is minimized.

Abstract: A method and system have a media path having moving devices that move a media sheet in a processing direction. At least two elongated sensors within the media path are positioned diagonally relative to the processing direction. The media sheet has two lateral sides, a leading edge, and a trailing edge. A registration controller is operatively connected to the media path and to the elongated sensors. Each of the elongated sensors simultaneously identifies: a location of one of the lateral sides of the media sheet, such that a combination of the elongated sensors simultaneously outputs at least two lateral measures of locations of the lateral sides of the media sheet; and at least one measure leading edge or at least one measure of the trailing edge of the media sheet.

Abstract: An inserting apparatus for inserting documents into envelopes comprising an envelope holder for holding an envelope in a document inserting position, wherein a first upstream end of the envelope is in an open position for receiving the document, a document displacement arrangement for displacing the document along a document inserting path into the envelope, wherein the apparatus further comprises a document steering arrangement arranged opposite to an envelope crease line provided between an envelope flap and an envelope body. The arrangement comprises steering elements spaced apart along a central axis that in use is substantially aligned with the envelope crease line. The steering elements are interconnected such that in use the respective steering elements are rotatable about the central axis in a similar direction with a similar speed during a similar time interval.

Abstract: A transporting device includes steering rollers, a center roller which is disposed between the steering rollers and deflection-detecting sensors that are positioned downstream from the steering rollers. When a sheet of paper has a width which is narrower than a width of a reference sheet of paper, the positional deflection of the sheet of paper is corrected by transporting the sheet of paper to a shift roller with the sheet of paper being nipped by the center roller and thrusting a forward end of the sheet of paper against a shift roller. When a sheet of paper has a width which exceeds the width of the reference sheet of paper, the positional deflection of the sheet of paper is corrected by rotating the steering rollers separately based on a detected result of the sensors with the sheet of paper being nipped by the steering rollers.

Abstract: A registration portion which conveys a sheet toward an image forming portion forming an image on the sheet includes a controlling portion which regulates a sheet skew feeding correction amount by the skew feeding correcting portion based on the sheet right angle degree detected by the end detection sensor. The controlling portion automatically calculates, from the sheet right angle degree detected by the end detection sensor, a skew feeding regulation amount used for making any one of the two sides, forming the corner of the sheet, parallel to the image and corrects the skew feeding of the sheet by the skew feeding correcting portion with the use of the skew feeding regulation amount so that any one of the two sides forming the corner of the sheet is parallel to the image.

Abstract: A skew correction device includes a first conveying unit arranged in a sheet conveying path; a second conveying unit arranged downstream of the first conveying unit in a conveying direction of a sheet; and a skew correction unit. When the sheet is unfolded paper, the skew correction unit performs a first skew correction that corrects for the skew of the sheet so that a leading edge of the sheet conveyed by the first conveying unit abuts on the second conveying unit that is stopped. When the sheet is fold paper, the skew correction unit performs a second skew correction that corrects for the skew of the sheet so that a leading edge of the sheet conveyed by the first conveying unit abuts the second conveying unit and the second conveying unit is driven in a reverse direction to the conveying direction at a predetermined operational timing.

Abstract: The skew feeding amount of a sheet front end is calculated according to the difference between timings when activation sensors detect the sheet front end, and the skew feeding amount of the sheet side edge is calculated according to the difference between side edge positions of the sheet detected by the first side registration detection sensor or the second side registration detection sensor. Further, whether a sheet is a rectangular sheet or a non-rectangular sheet is determined before skew feeding of the sheet is corrected, and, when the sheet is determined to be a rectangular sheet, the skew feeding correcting portion is controlled based on one of the sheet side edge skew feeding amount and sheet front end skew feeding amount and the skew feeding correcting portion is controlled based on the sheet side edge skew feeding amount when the sheet is determined to be a non-rectangular sheet.

Abstract: A paper delivering device includes a delivering module and a detecting module. The delivering module includes a paper tray for supporting at least one paper, at least one roller attached on the paper tray for delivering the at least one paper, and a blocking member pivotably attached to the paper tray. The detecting module detects whether the at least one paper is placed in a position predetermined as correct. The blocking member is locked at a first position to prevent the sliding movement of the at least one paper when the at least one paper is not placed at the predetermined position, or may be rotated to a second position to allow the forward movement of the at least one paper when the at least one paper is correctly placed.

Abstract: A sheet conveyance device that is capable of correcting skew of a sheet like an index sheet without complicating a use setting and without increasing a cost significantly. A plurality of conveyance units are arranged in a direction intersecting a sheet conveyance direction to convey a sheet. At least three detection sensors are arranged in a direction intersecting the conveyance direction at an upstream side from the conveyance units to detect the sheet. A skew amount computation unit measures a time difference between detection timings of a front end of the sheet by two of the at least three detection sensors except the detection sensor that detects first, and computes a front-end skew amount according to the time difference. A speed change unit makes the conveyance speeds of the conveyance units be different according to the front-end skew amount so as to correct the skew of the sheet.

Abstract: A sheet of material is received at a sensor assembly, which includes a sensor operable to measure a property of the sheet. An air flow is generated that is substantially tangential to the sheet in order to at least partially control a position of the sheet relative to the sensor assembly. For example, the sheet may be associated with an upstream boundary layer of air and a downstream boundary layer of air. At least part of the air from the upstream boundary layer could be removed and used to provide an air flow forming at least part of the downstream boundary layer. Also, the air flow could be provided between a surface of the sensor assembly and the sheet to at least partially control a distance of the sheet from the surface of the sensor assembly and/or an angle at which the sheet passes the surface of the sensor assembly.

Abstract: A document feeder to reverse a document by conveying the document to a reverse path. The document feeder includes a conveyance roller to convey the document, a reverse roller provided along a conveyance path of the document conveyed by the conveyance roller to convey the document to the reverse path by changing a direction of conveyance of the document, and a reverse roller control unit to control the reverse roller to correct skew of the document. The reverse roller control unit controls the reverse roller to correct the skew of the document by striking the document conveyed by the conveyance roller against a nip formed between the reverse roller and a roller provided opposite the reverse roller to temporarily bend the document.

Abstract: Accurate sheet registration is achieved by measuring the arrival of a leading edge and/or a trailing edge of the sheet using a first sensor. Also, measuring a first position of the sheet using a second sensor on a lateral edge of the sheet. Then performing a first adjustment moving the sheet laterally using the first position measurement. The first adjustment actuated prior to the sheet reaching a third sensor for measuring a second position of the sheet. The third sensor disposed downstream in the process direction of the second sensor and a sheet feeding nip. Then measuring a second position of the sheet using the third sensor on the lateral edge and performing a second adjustment of the sheet with regard to at least one of sheet skew, sheet velocity and sheet lateral position using at least one of the arrival, first position and second position measurements.

Abstract: A method and apparatus align an adjuster with an edge of media supported by a tray. The adjuster is operably coupled to a gauge that moves in response to movement of the adjuster. A sensor senses the gauge to detect a dimension of the media while the media is supported by the tray.

Abstract: A method and an apparatus for detecting a folded corner of a sheet in a sheet-fed printing press automatically select which of a pair of folded corner detectors provided integrally with right and left side lay devices should be used, in accordance with a setting of which of the side lay devices is to be used, thereby making it possible to raise the rate of operation and lightening the burden on an operator. When the left-hand side lay device is used, a first left-hand end detector supported in the left-hand side lay device and a second right-hand end detector supported in the right-hand side lay device are actuated. When the right-hand side lay device is used, a first right-hand end detector supported in the right-hand side lay device and a second left-hand end detector supported in the left-hand side lay device are actuated.

Abstract: The present invention relates to a media separating device of an automatic media dispenser. According to the present invention, when a skew of a medium is detected when the medium is separated and conveyed, a pick-up bracket mounted with a pick-up roller is rotated in a direction away from the push plate, so that the pick-up bracket is separated from the medium which is ready to be received in the media box.