US20070235925A1 - Constant lead edge paper inverter system - Google Patents

Constant lead edge paper inverter system Download PDF

Info

Publication number
US20070235925A1
US20070235925A1 US11/394,321 US39432106A US2007235925A1 US 20070235925 A1 US20070235925 A1 US 20070235925A1 US 39432106 A US39432106 A US 39432106A US 2007235925 A1 US2007235925 A1 US 2007235925A1
Authority
US
United States
Prior art keywords
sheet
transport path
processing direction
printing apparatus
along
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Abandoned
Application number
US11/394,321
Inventor
Donald Johnston
David Cipolla
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Xerox Corp
Original Assignee
Xerox Corp
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Xerox Corp filed Critical Xerox Corp
Priority to US11/394,321 priority Critical patent/US20070235925A1/en
Assigned to XEROX CORPORATION reassignment XEROX CORPORATION ASSIGNMENT OF ASSIGNORS INTEREST (SEE DOCUMENT FOR DETAILS). Assignors: CIPOLLA, DAVID, JOHNSTON, DONALD EUGENE
Publication of US20070235925A1 publication Critical patent/US20070235925A1/en
Abandoned legal-status Critical Current

Links

Images

Classifications

    • GPHYSICS
    • G03PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
    • G03GELECTROGRAPHY; ELECTROPHOTOGRAPHY; MAGNETOGRAPHY
    • G03G15/00Apparatus for electrographic processes using a charge pattern
    • G03G15/22Apparatus for electrographic processes using a charge pattern involving the combination of more than one step according to groups G03G13/02 - G03G13/20
    • G03G15/23Apparatus for electrographic processes using a charge pattern involving the combination of more than one step according to groups G03G13/02 - G03G13/20 specially adapted for copying both sides of an original or for copying on both sides of a recording or image-receiving material
    • G03G15/231Arrangements for copying on both sides of a recording or image-receiving material
    • G03G15/232Arrangements for copying on both sides of a recording or image-receiving material using a single reusable electrographic recording member
    • G03G15/234Arrangements for copying on both sides of a recording or image-receiving material using a single reusable electrographic recording member by inverting and refeeding the image receiving material with an image on one face to the recording member to transfer a second image on its second face, e.g. by using a duplex tray; Details of duplex trays or inverters
    • GPHYSICS
    • G03PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
    • G03GELECTROGRAPHY; ELECTROPHOTOGRAPHY; MAGNETOGRAPHY
    • G03G2215/00Apparatus for electrophotographic processes
    • G03G2215/00362Apparatus for electrophotographic processes relating to the copy medium handling
    • G03G2215/00367The feeding path segment where particular handling of the copy medium occurs, segments being adjacent and non-overlapping. Each segment is identified by the most downstream point in the segment, so that for instance the segment labelled "Fixing device" is referring to the path between the "Transfer device" and the "Fixing device"
    • G03G2215/00417Post-fixing device
    • G03G2215/0043Refeeding path
    • G03G2215/00438Inverter of refeeding path

Definitions

  • the present disclosure relates to digital document production equipment and, more specifically, to duplex capable imaging machines.
  • Digital document production equipment is very common in today's office environment.
  • such equipment which includes printers, copiers, facsimiles, or other multifunction machines, is configured to place text and images, based on digital data, onto media, such as paper sheets.
  • the digital copier also employs an edge position detector.
  • the edge position detector is configured to determine the location of a side edge of the sheet relative to a fixed point within the copier. That is, prior to subjecting the sheet to the marking device, the sheet passes over the edge position detector that registers the side edge of the sheet to ensure proper alignment and placement of the recorded image as the sheet is guided across the marking device.
  • duplex capable machines In order to print on both sides of the same sheet, duplex capable machines typically feed a sheet through the edge detector and marking device a first time to receive a first image on one side thereof, suck the sheet back out, invert or flip the sheet, and then re-feed the sheet back through the edge detector and marking device so that the device can place a second image on the opposite side of the sheet.
  • duplex path The path by which the sheet has been output by the marking device, inverted, and re-fed back to the marking device, is generally referred to as the “duplex path.”
  • duplex path The path by which the sheet has been output by the marking device, inverted, and re-fed back to the marking device, is generally referred to as the “duplex path.”
  • the registration of duplexed images should result in images recorded on opposite sides of the sheet to be substantially aligned with each other. In other words, the margins of the images on opposite sides of the sheet should appear to be superimposed.
  • the edge detector registers the side edge of the sheet that is opposite to the initially detected side edge, in anticipation of the sheet being re-fed back to the marking device. It will be appreciated that, given paper length and cut angle tolerances, the use and registration of opposite side edges increases the risks of duplex image misalignment and placement errors.
  • the printing apparatus includes a first transport path to route a sheet along a processing direction, an edge position detector to detect a lead edge of the sheet, a marking device that prints on a first side of the sheet, a second transport path to receive the sheet from the marking device, and an inverter mechanism that receives the sheet from the second transport path and inverts the sheet along a cross-processing direction that is perpendicular to the processing direction.
  • the printing apparatus also includes a third transport path that receives the inverted sheet and routes the inverted sheet back to the first transport path. With this configuration, upon being routed back to the first transport path, the edge position detector detects the same lead edge of the sheet as previously detected and the marking device prints on a second side of the sheet.
  • Other embodiments include a method of printing on opposite sides of a sheet, comprising routing the sheet across a first transport path along a processing direction, detecting a lead edge of the sheet, printing on one side of the sheet, routing the sheet across a second transport path, inverting the sheet along a cross-processing direction that is perpendicular to the processing direction, and routing the sheet across a third transport path that feeds back towards the first transport path.
  • the method further includes detecting the same lead edge, and printing on a second side of the sheet.
  • FIG. 1 depicts the principle of elements of duplex-capable printing apparatus, in accordance with an embodiment of the present invention
  • FIG. 2A depicts features of a sheet to be processed by the duplex-capable printing apparatus of FIG. 1 ;
  • FIG. 2B is a simplified diagram of FIG. 1 that depicts the orientation and alignment of a sheet at different time intervals.
  • the present invention provides a printing apparatus and method of providing duplex imaging with single lead edge registration.
  • FIG. 1 schematically depicts the principle elements of the image processing station of a duplex capable printing apparatus 100 , in accordance with an embodiment of the present invention.
  • printing apparatus 100 comprises a side edge position detector 110 , a marking device 120 , a simplex transport path 130 , and a constant lead edge paper inverter system 160 .
  • constant lead edge inverter system 160 comprises an upper duplex transport path 140 and a lower duplex transport path 150 .
  • the image processing direction that is, the general direction in which a sheet of paper is transported and routed to receive an image
  • P the cross processing direction (i.e., perpendicular to P)
  • P′ the cross processing direction
  • simplex transport path 130 configured for single-sided imaging and for accommodating possible duplex imaging, comprises a plurality of drive roller nips 102 oriented to guide a sheet of paper across side edge position detector 110 and marking device 120 along the image processing direction P. That is, in the case of single-sided imaging in which the digital signals representative of the captured image have been supplied to marking device 120 , the sheet is supplied to and enters the simplex transport path 130 at intake portion 131 and drive roller nips 102 engage the sheet and transport the sheet across side edge position detector 110 . Side edge position detector 110 registers the side edge of the sheet, in this case, the lead edge, to ensure proper alignment and placement of the recorded image. After registering the side edge, drive roller nips 102 guide the sheet across marking device 120 to record the captured image onto one side of the sheet. Finally, the single-sided imaged sheet is then routed to an output portion 139 of simplex path 130 .
  • constant lead edge inverter system 160 comprises an upper duplex transport path 140 and a lower duplex transport path 150 .
  • upper duplex transport path 140 comprises U-shaped inverter 145 , a plurality of drive roller nips 102 configured to guide and transport the sheet to inverter 145 , a plurality of cross-direction drive roller nips 142 and a sensor 143 configured to identify the lead edge of the sheet at a constant stop point S.
  • U-shaped inverter 145 may comprise rolls, vacuum transport, or any mechanism suitable for such purposes.
  • Both U-shaped inverter 145 and cross-direction drive roller nips 142 are oriented and configured to operate along the cross-process direction P′ direction.
  • the combination of U-shaped inverter 145 and cross-direction drive roller nips 142 cooperate to receive and engage the sheet of paper containing a previously recorded image on one side, flip the sheet along the cross-process direction P′ to the opposite side, and forward the flipped sheet to lower duplex transport path 150 .
  • Lower duplex transport path 150 is configured to receive and route the flipped sheet back over to the intake portion 131 of simplex transport path 130 in order for the marking device 120 to record a second image on the blank side of the sheet.
  • the sheet is supplied to and enters the simplex transport path 130 at intake portion 131 , so that drive roller nips 102 engage the sheet and transport the sheet across side edge position detector 110 .
  • the detector 110 registers the side edge (i.e., the lead edge) of the sheet to ensure proper alignment and placement of the first recorded image.
  • drive roller nips 102 guide the sheet across marking device 120 to record the first captured image onto one side of the sheet.
  • the sheet is routed to duplex path intake portion 141 .
  • FIG. 2A illustrates a sheet having a blank side SH 1 onto which a second image will be recorded thereon, a side SH 2 having a first recorded image, and the lead side edge E of the sheet having been identified and registered by side edge position detector 110 .
  • FIG. 2B illustrates the operation of constant lead edge inverter system 160 at different time intervals ti.
  • time interval t 1 represents the sheet after passing through side edge position detector 110 and marking device 120 , in which the first image is recorded on side SH 2 .
  • the sheet is routed to duplex path intake portion 141 where the drive roller nips 102 engage the sheet and transport the sheet along the upper process direction P, as indicated by time interval t 2 .
  • the sheet continues to be transported along the upper process direction P until reaching the upper drive roller nips 102 at the U-shaped inverter 145 , as indicated by time interval t 3 .
  • sensor 143 disposed proximate to the distal end of U-shaped inverter 145 , identifies the lead edge of the sheet at a constant stop point S under the cross-direction drive roller nips 142 .
  • the sheet is stopped and cross-direction drive roller nips 142 engage the sheet while drive roller nips 102 disengage.
  • the sheet is turned upside down so that recorded side SH 2 is on top and blank side SH 1 is on the bottom.
  • the cross-direction drive roller nips 142 drive the sheet in the cross-process direction P′ of the U-shaped inverter 145 .
  • the combination of cross-direction drive roller nips 142 and inverter 145 effectively flips the sheet and feeds the sheet to lower duplex transport path 150 , where the cross-direction drive roller nips 142 disengage and drive roller nips 102 on the lower path engage the sheet.
  • the flipping results in the sheet having blank side SH 1 on top while recorded side SH 2 is on the bottom.
  • the lead edge E remains on the same side after the sheet is flipped.
  • the lower path drive roller nips 102 transport the sheet along the lower processing path onto duplex output portion 159 , which directs the sheet back into a beginning portion of simplex path 130 .
  • the sheet is placed back on simplex path 130 prior to being imaged for the second time.
  • the sheet is once again turned upside down so that recorded side SH 2 is on top and blank side SH 1 is on the bottom.
  • lead edge E of the sheet remains on the side after the sheet is flipped.
  • the drive roller nips 102 on the simplex path 130 engage the sheet and transport the sheet across side edge position detector 110 , detector 110 registers the same lead edge E of the sheet, as previously registered.
  • drive roller nips 102 guide the sheet again across marking device 120 to record the second captured image onto the blank side SH 1 of the sheet, and thereafter, the duplex imaged sheet is routed to output portion 139 .
  • printing apparatus 100 is capable of rendering images on both sides of the sheet while maintaining the same lead edge.
  • the presentation of the same lead edge to the edge detector for both the pre-inverted and post-inverted sheet reduces the risks of duplex image misalignment and placement errors due to the use and registration of opposite side edges.
  • Other advantages may include higher throughput speeds, as the cross-direction drive roller nips do not have to reverse directions as conventional roller nips do when the sheets have to be sucked back out prior to flipping.

Landscapes

  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Separation, Sorting, Adjustment, Or Bending Of Sheets To Be Conveyed (AREA)
  • Registering Or Overturning Sheets (AREA)
  • Conveyance By Endless Belt Conveyors (AREA)

Abstract

A printing apparatus capable of duplex imaging that maintains the lead edge of a sheet constant, is disclosed. The printing apparatus includes a first transport path to route a sheet along a processing direction, an edge position detector to detect a lead edge of the sheet, a marking device that prints on a first side of the sheet, a second transport path to receive the sheet from the marking device, and an inverter mechanism that receives the sheet from the second transport path and inverts the sheet along a cross-processing direction that is perpendicular to the processing direction. The printing apparatus also includes a third transport path that receives the inverted sheet and routes the inverted sheet back to the first transport path. With this configuration, upon being routed back to the first transport path, the edge position detector detects the same lead edge of the sheet as previously detected and the marking device prints on a second side of the sheet.

Description

    BACKGROUND OF THE INVENTION
  • 1. Field of Invention
  • The present disclosure relates to digital document production equipment and, more specifically, to duplex capable imaging machines.
  • 2. Description of Related Art
  • Digital document production equipment is very common in today's office environment. Generally, such equipment, which includes printers, copiers, facsimiles, or other multifunction machines, is configured to place text and images, based on digital data, onto media, such as paper sheets.
  • By way of example, consider the case of digital copiers, where original documents bearing images to be recorded on paper sheets are typically loaded into the tray of a document handler. The documents are drawn one sheet at a time and moved relative to an image sensor. The image sensor records reflected light from a series of small areas in the original image as the image moves past the sensor to yield a set of digital signals representative of the image to be recorded on a sheet of paper. The digital signals are then supplied to a marking device, such as, for example, an electrophotographic laser printing device or an inkjet printhead device, which renders the recorded image on one side of the sheet of paper as the sheet passes across the marking device.
  • To ensure proper image placement and alignment, the digital copier also employs an edge position detector. The edge position detector is configured to determine the location of a side edge of the sheet relative to a fixed point within the copier. That is, prior to subjecting the sheet to the marking device, the sheet passes over the edge position detector that registers the side edge of the sheet to ensure proper alignment and placement of the recorded image as the sheet is guided across the marking device.
  • More sophisticated types of document production equipment are also capable of rendering images on both sides of a single sheet of paper, a feature commonly referred to as “duplexing” or “duplex imaging.” In order to print on both sides of the same sheet, duplex capable machines typically feed a sheet through the edge detector and marking device a first time to receive a first image on one side thereof, suck the sheet back out, invert or flip the sheet, and then re-feed the sheet back through the edge detector and marking device so that the device can place a second image on the opposite side of the sheet. The path by which the sheet has been output by the marking device, inverted, and re-fed back to the marking device, is generally referred to as the “duplex path.” Although the specific architectures vary, most conventional duplex paths employ an inverter transport loop that guides the lead edge of the paper sheet over the trail edge to effectively flip the sheet.
  • Ideally, the registration of duplexed images should result in images recorded on opposite sides of the sheet to be substantially aligned with each other. In other words, the margins of the images on opposite sides of the sheet should appear to be superimposed. However, as a practical matter, after the sheet has been sucked out and flipped by the inverter transport loop, the edge detector registers the side edge of the sheet that is opposite to the initially detected side edge, in anticipation of the sheet being re-fed back to the marking device. It will be appreciated that, given paper length and cut angle tolerances, the use and registration of opposite side edges increases the risks of duplex image misalignment and placement errors.
  • SUMMARY OF THE INVENTION
  • Principles of the present invention, as embodied and broadly described herein, provide a printing apparatus capable of duplex imaging that maintains the lead edge of a sheet constant. In one embodiment, the printing apparatus includes a first transport path to route a sheet along a processing direction, an edge position detector to detect a lead edge of the sheet, a marking device that prints on a first side of the sheet, a second transport path to receive the sheet from the marking device, and an inverter mechanism that receives the sheet from the second transport path and inverts the sheet along a cross-processing direction that is perpendicular to the processing direction. The printing apparatus also includes a third transport path that receives the inverted sheet and routes the inverted sheet back to the first transport path. With this configuration, upon being routed back to the first transport path, the edge position detector detects the same lead edge of the sheet as previously detected and the marking device prints on a second side of the sheet.
  • Other embodiments include a method of printing on opposite sides of a sheet, comprising routing the sheet across a first transport path along a processing direction, detecting a lead edge of the sheet, printing on one side of the sheet, routing the sheet across a second transport path, inverting the sheet along a cross-processing direction that is perpendicular to the processing direction, and routing the sheet across a third transport path that feeds back towards the first transport path. The method further includes detecting the same lead edge, and printing on a second side of the sheet.
  • BRIEF DESCRIPTION OF DRAWINGS
  • The accompanying drawings, which are incorporated in and constitute a part of the present patent specification, depict corresponding embodiments of the invention, by way of example only, and it should be appreciated that corresponding reference symbols indicate corresponding parts. In the drawings:
  • FIG. 1 depicts the principle of elements of duplex-capable printing apparatus, in accordance with an embodiment of the present invention;
  • FIG. 2A depicts features of a sheet to be processed by the duplex-capable printing apparatus of FIG. 1; and
  • FIG. 2B is a simplified diagram of FIG. 1 that depicts the orientation and alignment of a sheet at different time intervals.
  • DETAILED DESCRIPTION OF THE INVENTION
  • As will be evident by the ensuing detailed description, the present invention provides a printing apparatus and method of providing duplex imaging with single lead edge registration.
  • FIG. 1 schematically depicts the principle elements of the image processing station of a duplex capable printing apparatus 100, in accordance with an embodiment of the present invention. Such an apparatus is intended to cover printers, copiers, facsimiles, or other multifunction machines that are capable of duplex imaging. As illustrated in FIG. 1, printing apparatus 100 comprises a side edge position detector 110, a marking device 120, a simplex transport path 130, and a constant lead edge paper inverter system 160. In turn, constant lead edge inverter system 160 comprises an upper duplex transport path 140 and a lower duplex transport path 150. The orientation of FIG. 1 is depicted so that the image processing direction, that is, the general direction in which a sheet of paper is transported and routed to receive an image, is indicated by P, while the cross processing direction (i.e., perpendicular to P) is indicated by P′.
  • As shown in FIG. 1, simplex transport path 130, configured for single-sided imaging and for accommodating possible duplex imaging, comprises a plurality of drive roller nips 102 oriented to guide a sheet of paper across side edge position detector 110 and marking device 120 along the image processing direction P. That is, in the case of single-sided imaging in which the digital signals representative of the captured image have been supplied to marking device 120, the sheet is supplied to and enters the simplex transport path 130 at intake portion 131 and drive roller nips 102 engage the sheet and transport the sheet across side edge position detector 110. Side edge position detector 110 registers the side edge of the sheet, in this case, the lead edge, to ensure proper alignment and placement of the recorded image. After registering the side edge, drive roller nips 102 guide the sheet across marking device 120 to record the captured image onto one side of the sheet. Finally, the single-sided imaged sheet is then routed to an output portion 139 of simplex path 130.
  • As noted above, constant lead edge inverter system 160 comprises an upper duplex transport path 140 and a lower duplex transport path 150. In turn, upper duplex transport path 140 comprises U-shaped inverter 145, a plurality of drive roller nips 102 configured to guide and transport the sheet to inverter 145, a plurality of cross-direction drive roller nips 142 and a sensor 143 configured to identify the lead edge of the sheet at a constant stop point S. U-shaped inverter 145 may comprise rolls, vacuum transport, or any mechanism suitable for such purposes.
  • Both U-shaped inverter 145 and cross-direction drive roller nips 142 are oriented and configured to operate along the cross-process direction P′ direction. In particular, the combination of U-shaped inverter 145 and cross-direction drive roller nips 142 cooperate to receive and engage the sheet of paper containing a previously recorded image on one side, flip the sheet along the cross-process direction P′ to the opposite side, and forward the flipped sheet to lower duplex transport path 150.
  • Lower duplex transport path 150 is configured to receive and route the flipped sheet back over to the intake portion 131 of simplex transport path 130 in order for the marking device 120 to record a second image on the blank side of the sheet.
  • In an exemplary embodiment, consider the case in which duplex imaging has been selected and the two images to be recorded on opposite sides of the sheet have been digitally captured by the image sensor (not shown), so that the digital signals representative of the captured images have been supplied to marking device 120. Initially, much like the single-sided imaging case, the sheet is supplied to and enters the simplex transport path 130 at intake portion 131, so that drive roller nips 102 engage the sheet and transport the sheet across side edge position detector 110. The detector 110 registers the side edge (i.e., the lead edge) of the sheet to ensure proper alignment and placement of the first recorded image. After registering the side edge, drive roller nips 102 guide the sheet across marking device 120 to record the first captured image onto one side of the sheet. However, unlike the single-sided imaging case, where the single-sided imaged sheet is routed the to output portion 139, the sheet is routed to duplex path intake portion 141.
  • For the sake of clarity regarding the subsequent description of constant lead edge inverter system 160, reference is made to FIGS. 2A, 2B. FIG. 2A illustrates a sheet having a blank side SH1 onto which a second image will be recorded thereon, a side SH2 having a first recorded image, and the lead side edge E of the sheet having been identified and registered by side edge position detector 110. FIG. 2B illustrates the operation of constant lead edge inverter system 160 at different time intervals ti.
  • With this said, time interval t1 represents the sheet after passing through side edge position detector 110 and marking device 120, in which the first image is recorded on side SH2. After time interval t1, the sheet is routed to duplex path intake portion 141 where the drive roller nips 102 engage the sheet and transport the sheet along the upper process direction P, as indicated by time interval t2.
  • The sheet continues to be transported along the upper process direction P until reaching the upper drive roller nips 102 at the U-shaped inverter 145, as indicated by time interval t3. At this point, sensor 143, disposed proximate to the distal end of U-shaped inverter 145, identifies the lead edge of the sheet at a constant stop point S under the cross-direction drive roller nips 142. Upon reaching constant stop point S, the sheet is stopped and cross-direction drive roller nips 142 engage the sheet while drive roller nips 102 disengage. As depicted in FIG. 2B, the sheet is turned upside down so that recorded side SH2 is on top and blank side SH1 is on the bottom. It will be appreciated that, at this point, other quality control measures may be taken to further ensure proper alignment and image placement. For example, with the sheet being in a prone position on top of U-shaped inverter 145, gross deskewing and top edge registration could be performed to measure and account for side edge skew.
  • At time interval t4, the cross-direction drive roller nips 142 drive the sheet in the cross-process direction P′ of the U-shaped inverter 145. The combination of cross-direction drive roller nips 142 and inverter 145 effectively flips the sheet and feeds the sheet to lower duplex transport path 150, where the cross-direction drive roller nips 142 disengage and drive roller nips 102 on the lower path engage the sheet. As depicted in FIG. 2B, the flipping results in the sheet having blank side SH1 on top while recorded side SH2 is on the bottom. However, as also indicated in the figure, the lead edge E remains on the same side after the sheet is flipped.
  • As indicated by time interval t5, the lower path drive roller nips 102 transport the sheet along the lower processing path onto duplex output portion 159, which directs the sheet back into a beginning portion of simplex path 130.
  • At time interval t6, the sheet is placed back on simplex path 130 prior to being imaged for the second time. As depicted in FIG. 2B, by virtue of the lower duplex transport path 150, the sheet is once again turned upside down so that recorded side SH2 is on top and blank side SH1 is on the bottom. However, as noted above, lead edge E of the sheet remains on the side after the sheet is flipped. Subsequently, the drive roller nips 102 on the simplex path 130 engage the sheet and transport the sheet across side edge position detector 110, detector 110 registers the same lead edge E of the sheet, as previously registered. After registering the lead edge E, drive roller nips 102 guide the sheet again across marking device 120 to record the second captured image onto the blank side SH1 of the sheet, and thereafter, the duplex imaged sheet is routed to output portion 139.
  • Given the above-described configuration, printing apparatus 100 is capable of rendering images on both sides of the sheet while maintaining the same lead edge. The presentation of the same lead edge to the edge detector for both the pre-inverted and post-inverted sheet, reduces the risks of duplex image misalignment and placement errors due to the use and registration of opposite side edges. Other advantages may include higher throughput speeds, as the cross-direction drive roller nips do not have to reverse directions as conventional roller nips do when the sheets have to be sucked back out prior to flipping.
  • It will be appreciated that various of the above-disclosed and other features and functions, or alternatives thereof, may be desirably combined into many other different systems or applications. Also that various presently unforeseen or unanticipated alternatives, modifications, variations or improvements therein may be subsequently made by those skilled in the art which are also intended to be encompassed by the following claims.

Claims (16)

1. A printing apparatus, comprising:
a first transport path configured to route a sheet along a processing direction;
an edge position detector configured to detect a lead edge of the sheet;
a marking device configured to print on a first side of the sheet;
a second transport path configured to receive the sheet from the marking device;
an inverter mechanism configured to receive the sheet from the second transport path and invert the sheet along a cross-processing direction that is perpendicular to the processing direction; and
a third transport path configured to receive the inverted sheet and route the inverted sheet back to the first transport path,
wherein, upon being routed back to the first transport path, the edge position detector detects the same lead edge of the sheet and the marking device prints on a second side of the sheet.
2. The printing apparatus of claim 1, wherein the inverter mechanism comprises a U-shaped inverter.
3. The printing apparatus of claim 2, wherein the U-shaped inverter includes a plurality of rolls.
4. The printing apparatus of claim 2, wherein the U-shaped inverter includes a vacuum transport.
5. The printing apparatus of claim 1, wherein the first, second, and third transport paths are arranged to form a circuit path.
6. The printing apparatus of claim 1, wherein the first, second, and third transport paths include a plurality of drive roller nips that engage the sheet and are oriented and aligned to guide the sheet along the processing direction.
7. The printing apparatus of claim 1, wherein the inverter mechanism includes a plurality of cross-drive roller nips that engage the sheet and are oriented and aligned to guide the sheet along the cross-processing direction.
8. The printing apparatus of claim 1, wherein the first transport path includes an input portion to initially receive the sheet and an output portion to output the sheet.
9. The printing apparatus of claim 1, wherein the second transport path includes an intake portion to receive the sheet from the first transport path.
10. The printing apparatus of claim 1, wherein the third transport path includes an output portion to direct the sheet back to the first transport path.
11. A sheet inverter mechanism, comprising:
a U-shaped inverter configured to receive a sheet along a processing direction; and
a plurality of roller nips oriented and arranged to engage and drive the sheet across the U-shaped inverter to invert the sheet, the sheet being inverted along a cross-processing direction that is perpendicular to the processing direction,
wherein a lead edge of the sheet prior to being inverted remains on a same side after being inverted.
12. A method of printing on opposite sides of a sheet, comprising:
routing the sheet across a first transport path along a processing direction;
detecting a lead edge of the sheet;
printing on one side of the sheet;
routing the sheet across a second transport path;
inverting the sheet along a cross-processing direction that is perpendicular to the processing direction;
routing the sheet across a third transport path that feeds back towards the first transport path;
detecting the same lead edge; and
printing on a second side of the sheet.
13. The method of claim 12, wherein the inverting of the sheet includes engaging and driving the sheet across a U-shaped inverter along the cross-processing direction.
14. The method of claim 12, wherein the first, second, and third transport paths are arranged to form a circuit path.
15. The method of claim 12, wherein the routing of the sheet within the first, second, and third transport paths includes the use of a plurality of drive roller nips that are oriented and aligned to engage and guide the sheet along the processing direction.
16. The method of claim 12, wherein the inverting of the sheet includes the use of a plurality of cross-drive roller nips that are oriented and aligned to engage and guide the sheet along the cross-processing direction.
US11/394,321 2006-03-31 2006-03-31 Constant lead edge paper inverter system Abandoned US20070235925A1 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
US11/394,321 US20070235925A1 (en) 2006-03-31 2006-03-31 Constant lead edge paper inverter system

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
US11/394,321 US20070235925A1 (en) 2006-03-31 2006-03-31 Constant lead edge paper inverter system

Publications (1)

Publication Number Publication Date
US20070235925A1 true US20070235925A1 (en) 2007-10-11

Family

ID=38574388

Family Applications (1)

Application Number Title Priority Date Filing Date
US11/394,321 Abandoned US20070235925A1 (en) 2006-03-31 2006-03-31 Constant lead edge paper inverter system

Country Status (1)

Country Link
US (1) US20070235925A1 (en)

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20100278575A1 (en) * 2009-05-01 2010-11-04 Konica Minolta Business Technologies, Inc. Image forming apparatus
US20110211898A1 (en) * 2010-02-26 2011-09-01 Canon Kabushiki Kaisha Printing apparatus and control method of printing apparatus
US20130214479A1 (en) * 2010-07-28 2013-08-22 Dirk Dobrindt Sheet-transport device, sheet-turning unit and method for turning sheets
US20130320615A1 (en) * 2012-06-04 2013-12-05 Konica Minolta, Inc. Image forming apparatus
US20170326889A1 (en) * 2016-05-13 2017-11-16 Océ Holding B.V. Duplex printing system for cut sheets and a method therefore

Citations (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4432541A (en) * 1981-08-27 1984-02-21 International Business Machines Corporation Recirculating document feed apparatus and method for aligning documents therein
US4761001A (en) * 1984-07-10 1988-08-02 Canon Kabushiki Kaisha Automatic document feeder
US6044760A (en) * 1997-11-05 2000-04-04 Heidelberger Druckmaschinen Ag Reversing device with a linear drive for a sheet-fed rotary printing press
US6373042B1 (en) * 2000-08-29 2002-04-16 Xerox Corporation Registration system for a digital printer which prints multiple images on a sheet
US6401610B1 (en) * 1998-07-28 2002-06-11 Heidelberger Druckmaschinen Ag Method for taking over a sheet by a trailing edge thereof from an upline cylinder of a sheet-fed rotary printing press, and a transmission system for performing the method
US6554276B2 (en) * 2001-03-30 2003-04-29 Xerox Corporation Flexible sheet reversion using an omni-directional transport system
US6669192B2 (en) * 2001-07-18 2003-12-30 Ferag Ag Method and device for transforming a conveying stream of flat articles
US6726198B2 (en) * 2001-01-23 2004-04-27 Heidelberger Druckmaschinen Ag Device for aligning sheets of printed materials
US6767013B2 (en) * 2001-05-04 2004-07-27 Mathias Bäuerle GmbH Turning device for individual sheets
US6993282B2 (en) * 2003-03-31 2006-01-31 Canon Kabushiki Kaisha Sheet conveying apparatus and image forming apparatus

Patent Citations (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4432541A (en) * 1981-08-27 1984-02-21 International Business Machines Corporation Recirculating document feed apparatus and method for aligning documents therein
US4761001A (en) * 1984-07-10 1988-08-02 Canon Kabushiki Kaisha Automatic document feeder
US6044760A (en) * 1997-11-05 2000-04-04 Heidelberger Druckmaschinen Ag Reversing device with a linear drive for a sheet-fed rotary printing press
US6401610B1 (en) * 1998-07-28 2002-06-11 Heidelberger Druckmaschinen Ag Method for taking over a sheet by a trailing edge thereof from an upline cylinder of a sheet-fed rotary printing press, and a transmission system for performing the method
US6373042B1 (en) * 2000-08-29 2002-04-16 Xerox Corporation Registration system for a digital printer which prints multiple images on a sheet
US6726198B2 (en) * 2001-01-23 2004-04-27 Heidelberger Druckmaschinen Ag Device for aligning sheets of printed materials
US6554276B2 (en) * 2001-03-30 2003-04-29 Xerox Corporation Flexible sheet reversion using an omni-directional transport system
US6767013B2 (en) * 2001-05-04 2004-07-27 Mathias Bäuerle GmbH Turning device for individual sheets
US6669192B2 (en) * 2001-07-18 2003-12-30 Ferag Ag Method and device for transforming a conveying stream of flat articles
US6993282B2 (en) * 2003-03-31 2006-01-31 Canon Kabushiki Kaisha Sheet conveying apparatus and image forming apparatus

Cited By (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20100278575A1 (en) * 2009-05-01 2010-11-04 Konica Minolta Business Technologies, Inc. Image forming apparatus
US8437684B2 (en) * 2009-05-01 2013-05-07 Konica Minolta Business Technologies, Inc. Image forming apparatus
US20110211898A1 (en) * 2010-02-26 2011-09-01 Canon Kabushiki Kaisha Printing apparatus and control method of printing apparatus
US8430586B2 (en) * 2010-02-26 2013-04-30 Canon Kabushiki Kaisha Printing apparatus and control method of printing apparatus
US20130214479A1 (en) * 2010-07-28 2013-08-22 Dirk Dobrindt Sheet-transport device, sheet-turning unit and method for turning sheets
US8820737B2 (en) * 2010-07-28 2014-09-02 Eastman Kodak Company Sheet-transport device, sheet-turning unit and method for turning sheets
US20130320615A1 (en) * 2012-06-04 2013-12-05 Konica Minolta, Inc. Image forming apparatus
US8746691B2 (en) * 2012-06-04 2014-06-10 Konica Minolta, Inc. Image forming apparatus
US20170326889A1 (en) * 2016-05-13 2017-11-16 Océ Holding B.V. Duplex printing system for cut sheets and a method therefore
US10137701B2 (en) * 2016-05-13 2018-11-27 Océ Holding B.V. Duplex printing system for cut sheets and a method therefore

Similar Documents

Publication Publication Date Title
US7583282B2 (en) Image printing apparatus and image printing method
JP6833340B2 (en) Image reader and image forming device
US20120269563A1 (en) Transporting device and image forming apparatus using the same
US6340984B1 (en) Image forming apparatus for correcting an angle of inclination of the recording material and for recording corrected image
US20070235925A1 (en) Constant lead edge paper inverter system
JP2010269862A (en) Paper sheet conveying device, image reading device, and image forming device
JP2007070037A (en) Automatic document feeder, and image reader
JP4693725B2 (en) Sheet conveying apparatus and image forming apparatus
JP2006347645A (en) Image forming apparatus
JP2019147663A (en) Sheet conveying device, automatic document conveying device, image reading device and image forming device
JP4701612B2 (en) Image forming apparatus and method, and image forming result inspection method
JP5325350B1 (en) Image forming apparatus
JP2017194610A (en) Image forming apparatus
JP5340007B2 (en) Image forming apparatus
JP2000153967A (en) Image forming device
JP2006094090A (en) Image printing device, device and method for printing result inspection
JP6579437B2 (en) Document conveying apparatus and image forming apparatus
JP4232644B2 (en) Image forming apparatus, printing result inspection apparatus, and flexible sheet member positioning method
JP4198633B2 (en) Image forming apparatus, image reading apparatus, image forming method, image forming program, and recording medium therefor
JP3808770B2 (en) Sheet transport device
JP2011195211A (en) Recording medium carrying device and image forming device
US9250598B2 (en) Image forming apparatus with an arc-shaped duplex feed path having increased radius of curvature
JP4883893B2 (en) Image forming apparatus
JP2004244125A (en) Inspection device and image formation device
JP6134939B2 (en) Image forming system

Legal Events

Date Code Title Description
AS Assignment

Owner name: XEROX CORPORATION, CONNECTICUT

Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNORS:JOHNSTON, DONALD EUGENE;CIPOLLA, DAVID;REEL/FRAME:017948/0311

Effective date: 20060330

STCB Information on status: application discontinuation

Free format text: ABANDONED -- FAILURE TO RESPOND TO AN OFFICE ACTION