Document image acquisition system and document image acquisition method

Abstract

A method and apparatus for processing documents is provided. The documents may be conveyed to a feeder for feeding the documents to a scanner. The scanner acquires image data by scanning each document and ejects the documents to one or more output or sorting locations. The method may include a deskewing reduction assembly for reducing skew of the documents as they are fed to the scanner. The method may also include elements for improving image quality and reducing damage to the documents during scanning of the documents. The method may further include features for improving stacking of the ejected documents.

Description

REFERENCE TO RELATED APPLICATIONS

[0001] This application claims priority to U.S. Provisional Patent Application No. 63 / 325,605, filed March 30, 2022, which is incorporated herein by reference. This application is also related to U.S. Patent Application No. 18 / 129,063, filed March 30, 2023, which is incorporated herein by reference. [Technical field]

[0002] The present invention relates to the field of document processing. The invention has particular application in the field of document image acquisition, where documents are fed into an image acquisition system such as a document scanner. [Background technology]

[0003] Automated and semi-automated machines have been used for document processing. There have been many improvements in the area of ​​document processing, such as scanning and sorting incoming mail and other documents. However, a need remains for improvements in document handling and processing. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] U.S. Patent No. 9,079,730 Summary of the Invention [Problem to be solved by the invention]

[0005] The document processing system of the present invention provides many improvements in the document processing field, including separate inventions in document handling and document scanning. Although each of these improvements has been incorporated into a single document processing system, each improvement may also be used as a separate invention in a document processing system. [Means for solving the problem]

[0006] For example, according to a first aspect, there is provided a system including a scanner for scanning a document, such as a receiving envelope, to obtain image data of the scanned document. According to another aspect, a document processing system is provided that includes a conveyor for receiving documents, a plurality of output locations configured to receive the documents from the conveyor, and a sorting device for sorting the documents to the output locations. Optionally, the conveyor may be configured to transport the documents along the document path without holding down the documents.

[0007] According to a further aspect, a document processing system is provided that includes a document processing device including a scanner, a conveyor, a feeder that feeds a document from the conveyor to the scanner, and a skew reduction means that prevents the document from rotating about a vertical axis as the feeder feeds the document. Optionally, skew reduction means may be arranged upstream of the feed device. Additionally, the feed device may be configured to provide a net forward force to the first side of the document at a point spaced laterally from the centerline of the document, and the skew reduction means may provide a resistance force to the first side of the document at a location spaced from the centerline of the document in a direction opposite to the net forward force.

[0008] According to another aspect, a document processing system may provide a document processing method including the steps of: feeding a document in a first direction along a document path by applying a feed force that generates a torque in a first direction to a leading portion of the document at a location spaced from a centerline of the width of the document; and applying an anti-skew force to a trailing portion of the document while the feed force is being applied to the leading portion of the document, the anti-skew force being in a direction opposite to the direction of the feed force and being applied at a location spaced from the centerline of the width of the document.

[0009] According to a further aspect, the document processing system provides a document processing device including means for feeding a plurality of documents towards a document transport device and means for sorting the documents into one or more output bins. The sorting means may include a document transport device configured to transport documents at a first speed, and an output transport device configured to transport the documents from the document transport device toward a first of the one or more output bins, selectively accelerate the speed of the documents to a second speed, and then decelerate the speed of the documents to a third speed slower than either the first speed or the second speed.

[0010] According to yet another aspect, a method of document processing may be provided that includes a document processing system feeding a plurality of documents, one at a time, toward a document transport device and sorting the documents into one or more output bins. Sorting the documents may include varying the speed of the documents as they are ejected. For example, the document may be accelerated before it is ejected. Additionally, the speed may be increased and then decreased before the document is ejected.

[0011] Although the method and apparatus are described herein with reference to several exemplary embodiments and illustrative figures, the present method and apparatus for scanning and processing documents is not limited to the described embodiments or figures. The drawings and the detailed description related thereto are not intended to limit the embodiments to the particular forms disclosed. The headings used herein are for organizational purposes only and are not meant to limit the scope of the specification or the claims. As used herein, the word "may" is used in its permissive sense (i.e., may) rather than its required sense (i.e., must). Similarly, the word "including" means including but not limited to. [Brief description of the drawings]

[0012] The detailed description of the invention is best understood when read in conjunction with the accompanying drawings.

[0013] [Figure 1] FIG. 1 is a perspective view of a document processing system.

[0014] [Diagram 2] 2 is an enlarged rear perspective view of a feeder of the document processing system shown in FIG. 1;

[0015] [Diagram 3] FIG. 3 is an enlarged rear perspective view of the feeder shown in FIG. 2 with the pre-feeder in a raised position;

[0016] [Figure 4] FIG. 3 is an enlarged partial side view of the feeder shown in FIG. 2 .

[0017] [Diagram 5] FIG. 3 is a partial plan view of the feeder shown in FIG. 2 .

[0018] [Figure 6] 2 is a perspective view of an image capture assembly of the document processing system shown in FIG. 1.

[0019] [Figure 7] FIG. 7 is an enlarged partial side view of the image acquisition assembly shown in FIG. 6.

[0020] [Figure 8] 8 is a cross-sectional view of the image capture assembly shown in FIG. 6 taken along line 8-8.

[0021] [Figure 9] 2 is an exploded side view of a feeding device and a sorting device of the document processing system shown in FIG. 1.

[0022] [Figure 10] 10 is an enlarged, partial side view of a portion of the sorting device shown in FIG. 9.

[0023] [Figure 11] 10 is a partial rear perspective view of a portion of the sorting device shown in FIG. 9.

[0024] [Figure 12] 10 is an enlarged partial perspective view of a portion of the sorting device shown in FIG. 9.

[0025] [Figure 13] 10 is an enlarged partial perspective view of a portion of the sorting device shown in FIG. 9.

[0026] [Figure 14] 10 is an enlarged, partial side view of a portion of the sorting device shown in FIG. 9. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0027] Some portions of the detailed description of the invention which follow are described in terms of operations on binary digital signals stored within the memory of a particular apparatus or special purpose computer or platform. In this particular specification, the term specific apparatus or the like includes a general purpose computer that is programmed to perform particular functions pursuant to instructions from program software. The operations or processing herein involve physical manipulations of physical quantities. Usually, though not necessarily, these quantities take the form of electrical or magnetic signals capable of being stored, transferred, combined, compared, and otherwise manipulated. It is sometimes convenient, principally for reasons of common usage, to refer to such signals as bits, data, values, elements, symbols, characters, terms, numbers, numeric values, or the like. It should be understood, however, that all of these or similar terms are to be associated with appropriate physical quantities and are merely convenient labels. Unless otherwise indicated, and as will become apparent from the description that follows, descriptions using terms such as "processing," "computing," "determining," and the like throughout this specification will be understood to refer to the operations or processing of a specific apparatus, such as a special purpose computer or similar special purpose electronic computer. Thus, as used herein, a special purpose computer or similar special purpose electronic computer can manipulate or transform signals that are normally represented as physical electronic or magnetic quantities within the memory, registers or other information storage, transmission or display devices of the special purpose computer or similar special purpose electronic computer.

[0028] Referring now to the figures generally, and to FIG. 1 in particular, there is shown a document scanning station 10. The workstation 10 processes documents by dropping them, either individually or in stacks, onto a conveyor which transports the documents to an image capture station. The image capture station separates the documents and sequentially feeds the documents to an image capture device which captures image data of the documents. The documents are then sorted into one or more output bins.

[0029] The invention has particular application in a workplace 10 for document processing purposes, and in particular for processing document batches in which documents are scanned to obtain image data. In an embodiment, workstation 10 is configured as a semi-automated system that processes a variety of document types, including documents of various sizes as well as folded documents, such as documents removed from envelopes. The system may be integrated into a larger document processing system that includes elements such as a cutting station for slicing envelopes and a removal station for opening envelopes and removing documents for presentation to a user. Such a document processing system is described in detail in US Pat. No. 6,399,323, the entire disclosure of which is incorporated herein by reference. However, it should be understood that the document processing system also applies to systems that do not incorporate document retrieval functionality, but instead serve general document processing purposes. For example, the functionality of the document processing system may be incorporated into a system that includes a conveyor, image capture station, and sortation station, without including pick functionality. Thus, in the following description, the term document, as used throughout the specification and claims, unless otherwise noted, refers to any kind of written or printed matter, and may include envelopes and other mailings. Moreover, the document processing system functionality is generally applicable to any document processing system where it is desirable to manually feed a batch of documents to the document processing system without having to organize or prepare the batch for feeding to the document processing system.

[0030] The work station 10 includes a scanner 60 that scans documents to obtain image data of the documents. Additionally, workstation 10 may include any of a variety of feeding mechanisms for feeding documents to scanner 60 . In the embodiment shown in Figures 1-3, the document processing system may include a horizontal drop conveyor 40 configured to receive documents in a generally flat or horizontal orientation. The drop conveyor 40 transports the documents to a feeder 50 . Feeder 50 is configured to continuously feed documents to scanner 60 . Feeder 50 is preferably configured to receive stacks of documents from drop conveyor 40, separate individual documents from the stack, and store the stack so that the documents can be fed sequentially to scanner 60.

[0031] In the scanner 60, each document is scanned to obtain optical image data for each document. The scanned documents are sorted into one of a number of output bins 70 . Alternatively, the scanned document is ejected into a bypass or through path 75.

[0032] With the above in mind, a general overview of the flow of documents through workshop 10 is as follows: First, one or more documents are provided for processing. For example, a stack of documents called jobs is provided. To process a document, an operator unfolds the document if necessary and drops or places the document on the drop conveyor 40 . The drop conveyor 40 transports the documents towards a scanner or image capture station 60 . An image acquisition station feeder 50 receives documents from the drop conveyor 40 and controls the feeding of the documents to an image acquisition station 60 . The image capture station feeder 50 is configured to receive and feed documents of various sizes and conditions. For example, a document may be folded or creased, such as a document removed from an envelope. When the document is removed and opened, it may have creases or folds so that it is not flat. The image capture station feeder 50 is preferably configured to receive such documents, even if they are creased or folded, and to continuously feed the folded documents to the image capture station 60 with minimal manual preparation by the operator.

[0033] Image capture station 60 contains image capture devices that capture image data for each document as the document passes through the device. For example, the image capture device is preferably a scanner 60 that captures grayscale or color image data representative of an image of each document. The scanner 60 scans each document at multiple points as the document passes through the scanner 60 . The data acquired by the scanner 60 is processed by one or more image processing devices. The image processor may be in the form of a microprocessor on a separate image computer that is connected to the line scan camera. However, in this embodiment, the image processor is a processor integrated into the line scan camera assembly. The image processor can convert the image data to grayscale (eg, 8-bit grayscale). Additionally, as will be explained further below, the image processor can binarize grayscale image data to provide a black and white representation of the document image.

[0034] The image data is then stored in short-term or long-term storage. For example, an image processing system may be connected to a network to output document images and store them in a server 250 such as a file server. The server 250 may be a local server or a remote server. As previously mentioned, the image processing system binarizes the image data to create a black and white image. In this embodiment, the binarized data is analyzed and used to control further processing of the document. However, the binarized image data does not need to be stored on a file server. Instead, the grayscale image data is stored on an image server.

[0035] From the image capture device, an image transport device carries the documents to a sortation station 70 where the documents are sorted into a number of output bins. Documents can be sorted in a variety of ways. For example, documents can be sorted based on document information obtained from image data received at image acquisition site 60 . Alternatively, an operator may specify information about the documents before scanning, and the documents may be sorted based on the operator-specified information. As a further alternative, the documents may be stacked in one or more bins based on the order in which they are to be processed.

[0036] The operation of the various devices is controlled by a central controller such as a microprocessor 90 . A central controller 90 controls the processing of mail pieces in response to signals received from various sensors in various locations in the work station 10, and in response to parameters set for a job by an operator. The central controller 90 may also function as an image processor. In particular, microprocessor 90 may be configured to process image data acquired by scanner 60 . For example, image processor 90 may process image data to attempt to identify and read text. Similarly, the imaging device may attempt to identify and read indicia such as bar codes. Additionally, the image processing system may include input / output devices that provide information to an operator and allow the operator to input information regarding the document being processed. For example, an operator may enter data that controls how a batch of documents is processed. Additionally, the operator may enter information that controls how a particular document or document batch is processed. The input / output device may be a touch screen display. Alternatively, the system may include any of a variety of input mechanisms, such as a mouse, touchpad, pen input, keyboard, etc. [Input conveyor]

[0037] The operator may prepare one or more documents and place them directly on the image capture site feeder 50 . Additionally, the image processing system may include an input conveyor for transporting documents to the image capture feeder 50 . The input conveyor may be any of a variety of vertical or horizontal conveyors. FIG. 1 illustrates an exemplary embodiment in which the input conveyor is a horizontal conveyor configured to receive documents in a generally horizontal orientation. The input conveyor may be referred to as a drop conveyor because it is configured to receive documents dropped onto the input conveyor and advance the dropped documents to the image capture station feeder 50 .

[0038] The input conveyor 100 may be positioned along the front edge of the station 10 such that the input conveyor 100 can transport documents adjacent to and parallel to the front edge of the station 10 . Additionally, input conveyor 100 preferably transports dropped documents toward the left side of workstation 10 as viewed from the perspective of FIG.

[0039] The input conveyor 100 is preferably configured to easily receive a variety of documents of different sizes and different orientations. Additionally, the input conveyor 100 is preferably configured to transport documents that are not necessarily flat, such as documents that are creased. More specifically, the input conveyor 100 may be configured to simply receive documents dropped onto the input conveyor 100 and then transport the dropped documents to the image capture station 210 . In this manner, the operator can minimize the work involved by simply unfolding the documents and dropping the document or document stack onto the input conveyor 100 in preparation for scanning the documents.

[0040] FIG. 1 shows an embodiment in which the drop conveyor is a roller bed conveyor. The roller bed provides a generally horizontal surface onto which the document can be dropped. The roller bed consists of a number of horizontally arranged cylindrical rollers driven by a belt that engages the bottom of the rollers. The belt is driven by a motor that is controlled by the system controller. When a document is placed or dropped onto the rollers, it rests on the rollers. Thus, as the roller 102 rotates, it moves the document forward.

[0041] The rollers 102 are parallel to each other and perpendicular to the direction of travel so that the document moves in a straight line along the roller bed 100 . However, it is preferred that rollers 102 are disposed at an angle so that rollers 102 drive the document forward along the roller bed and laterally towards registration rail 105 . In this manner, the skew rollers 102 move the document against the rails 105 aligning the edges of the document against the rails 105 .

[0042] Although the drop conveyor 100 is described as a roller bed conveyor, other types of conveyors may be used as the drop conveyor 100. For example, the drop conveyor 100 may consist of a horizontal conveyor belt. If a conveyor belt is used, it is preferred that the belt be angled toward the rail 105 so that the documents are aligned against the rail 105 . Alternatively, rather than being a single conveyor belt, the drop conveyor 100 may be made up of multiple smaller conveyor belts onto which documents can be dropped.

[0043] Although the drop conveyor 100 is referred to as a horizontal conveyor, the drop conveyor 100 is preferably inclined downward so that gravity forces the documents towards the guide rails 105 . The drop conveyor 100 is preferably inclined at an angle of about 5 degrees, although this angle may be greater, and in fact the angle of the drop conveyor 100 may be so great that it is vertical rather than horizontal. Additionally, image capture station 210 and sortation station 70 are preferably inclined downwardly, similar to drop conveyor 100. [Image acquisition feeder]

[0044] Further details of the image capture feeder 110 will now be described with reference to FIGS. The image capture station feeder 110 is positioned adjacent to the end of the drop conveyor 100 , which transports documents to the image capture station feeder 110 , which feeds the documents to the image capture station 210 . As the document is being transported to the image capture station feeder 110 , the document is positioned approximately horizontally and rests on the drop conveyor 100 with the document edge aligned with the registration rail 105 .

[0045] The image capture station feeder 110 can continuously feed documents from the drop conveyor 100 to the image capture station 210 so that images can be captured individually from the documents. The image capture feeder 110 is operable to receive various types of documents, including individual documents, envelopes and stacks of envelopes. In the following description, a document stack should be understood to mean a group of two or more overlapping documents rather than a stack of interrelated documents that are fed sequentially to the image capture feeder 110. A document batch may be as few as two documents or may be much larger. Specifically, as described further below, the image processing system may be configured to process thick stacks of 50, 100, or even hundreds of documents. A thick stack of documents is commonly called a stack. However, for ease of explanation, it should be understood that a document batch includes any grouping of two or more documents, including thick stacks commonly referred to as stacks.

[0046] When processing a batch of documents, the image acquisition station feeder 110 separates the documents from one another and sequentially feeds each document in the batch to the image acquisition station 210 . The image capture station feeder 110 includes a pre-feed assembly 120 and a separation mechanism 180 . The pre-feed assembly 120 is configured to prepare the document stack for feeding to the feeder 180, thereby reducing the possibility of a paper jam occurring as the document stack enters or is processed by the feeder.

[0047] The pre-feed assembly 120 includes a first pre-feed assembly 130 and a second pre-feeder 140 which control the movement of the document stack from the drop conveyor 100 to a feeder 180 . The first pre-feed assembly 130 includes a pair of opposed rollers 132 and 134 forming a pinch mechanism. An angled belt 115 at the end of the registration rail 105 extends from the drop conveyor 100 to guide documents downward toward the nip mechanism of the first pre-feed assembly 130 . More specifically, for unfolded but creased documents, or documents that are not flat, the top edge of the document will tend to be spaced away from the surface of the drop conveyor 100 . The alignment rail 105 has an edge that extends beyond the drop conveyor 100 , and as the drop conveyor 100 moves the document towards the alignment rail 105 , the top edge of the document moves below the edge of the alignment rail 105 . The angled belt 115 interacts with the alignment rail 105 to flatten the top edge of the folded document downward onto the drop conveyor 100 so that the leading edge of the document can enter the clamping mechanism of the first pre-feed assembly 130 without being folded.

[0048] As mentioned above, the first pre-feed assembly 130 includes an upper roller 132 and a lower roller 134 that form a nip mechanism. The upper roller 132 is a drive roller and the lower roller 134 is a driven roller. The upper roller 132 is mounted on a moveable arm that rotates about a pivot point. A biasing element biases the pivot shaft to urge the upper roller 132 towards the lower roller 134 . As a document enters the first pre-feed assembly 130, the upper roller 132 and pivot arm rotate away from the lower roller 134 against the force of the biasing element to create a gap large enough to accommodate the document or stack of documents entering the first pre-feed assembly 130.

[0049] As the trailing end of the document or document stack exits the first pre-feed assembly 130 , the upper roller 132 rotates into position to engage the lower driven roller 134 until the next document or document stack enters the first pre-feed assembly 130 . Alternatively, if the document stack contains many documents, the actuator may rotate the upper roller 132 upward (counterclockwise from the perspective of FIG. 4) to reduce the likelihood that the first pre-feed assembly 130 will push out the top documents of the document stack as the document stack enters the first pre-feed assembly 130.

[0050] From the first pre-feed assembly 130 , the document enters a second pre-feed assembly 140 . The second pre-feed assembly 140 also includes an upper drive roller 142 that is biased against a lower driven roller 144 to form a pinch mechanism.

[0051] As mentioned above, the first and second pre-feed assemblies 130, 140 have upper drive rollers 132, 142 biased against opposing lower driven rollers 134, 144. The upper drive rollers 132, 142 can rotate to accommodate thicker document stacks, but as the document stack enters the pre-feed assembly 120, the upper rollers 132, 142 may push the top document in the stack backwards (i.e., upstream toward the drop conveyor 100). To keep the document stack neatly stacked, it may be desirable to automatically lift the upper rollers 132 , 142 of the pre-feed assembly 120 before the document stack enters the first pre-feed assembly 130 .

[0052] The pre-feed assembly 120 is controlled to rotate the pre-feeder arm upward before each document or stack of documents enters the pre-feed assembly 120 . However, raising the pre-feed rollers 132 and 142 is useful when the document stack is primarily a thick stack of many documents. Thus, the system monitors the thickness of the documents being transported along the drop conveyor 100 . If the document stack exceeds the threshold, the prefeeder arm is raised before the document stack enters the prefeed assembly 120 .

[0053] A variety of sensors can be used to measure the thickness of the stack of documents on the drop conveyor 100 . In this embodiment, one or more sensors are mounted on an adjustment rail upstream of the pre-feed assembly 120 . When the sensor detects a thickness above a threshold, the controller sends a signal to a motor connected to the pre-feed arm to raise the arm.

[0054] As the upper rollers 132 , 142 rise, the drop conveyor 100 continues to feed the document stack forward into the pre-feed assembly 120 . A first sensor between the first pre-feed assembly 130 and the second pre-feed assembly 140 is operable to detect the leading edge of the document stack. When the first sensor detects the leading edge of the thick document stack, the first pre-feed arm rotates downward so that the upper drive roller 132 contacts the topmost document in the document stack. The upper roller 142 of the second pre-feed assembly 140 may also be lowered at the same time.

[0055] As shown in FIG. 4, a document stack detector 145 is disposed between the first pre-feed assembly 130 and the second pre-feed assembly 140 . The document stack detector 145 may be configured to provide an indication of the number of documents being transported from the first pre-feed assembly 130 to the second pre-feed assembly 140 . In one method, thickness detector 145 determines the thickness of a document or stack of documents and estimates the number of documents based on the assumed thickness of each individual document. However, in this embodiment, thickness detector 145 does not directly measure the thickness of the document or document stack. Instead, thickness detector 145 is an ultrasonic detector that uses ultrasonic waves transmitted by a transmitter and received by a receiver. Based on the signals received by the receiver, the change in the number of sheets of paper can be determined and the number of documents in the stack can be assessed. More specifically, document stack detector 145 detects whether the document in pre-feed assembly 120 is a stack of two or more documents rather than a single document.

[0056] From the first pre-feed assembly 130 and the second pre-feed assembly 140 , the documents advance to a separator mechanism 180 . The separation mechanism 180 is a feed belt that rotates around a series of rollers. A blocking mechanism opposite the feeder defines an entrance path for the document stack. Rotation of the separator mechanism 180 in a first direction advances the topmost document from the stack and the blocking mechanism prevents movement of the remaining documents in the stack. In this manner, the feeder feeds the documents one by one to the image capture location 210 .

[0057] As shown in FIG. 5, when a first edge of document 20 is aligned against alignment rail 105, a separator mechanism 180 located adjacent the aligned edge engages document 20. As shown in FIG. In this manner, the separating mechanism 180 may apply a forward driving force to the document 20 at a point spaced from the centerline of the document 20 . Therefore, when the separating mechanism 180 drives the document 20 forward, a forward force is applied to the document 20, which may cause the document 20 to skew. Skew refers to the rotation of document 20 causing the edge of the paper to shift or rotate laterally relative to the direction of travel. Specifically, when document 20 is properly oriented, the edges of document 20 are parallel to alignment rails 105 . Skew refers to the lateral angular movement of document 20 relative to registration rail 105 , causing an edge of document 20 to rotate or shift laterally relative to registration rail 105 .

[0058] Skew can adversely affect the scanned image of document 20 . Therefore, the pre-feed assembly 120 optionally includes a mechanism to prevent or reduce skew as the document 20 is fed to the image acquisition station 210 .

[0059] 2-5, a skew reduction assembly 150 is shown. The deskew reduction assembly 150 is configured to apply a force to the document 20 to prevent the document 20 from rotating or skewing in response to the force applied by the separating mechanism 180 . In particular, the skew reduction assembly 150 exerts a rearwardly directed drag force on the document 20 in a direction opposite to the driving force exerted by the separating mechanism 180 . Additionally, as shown in FIG. 5, the skew reduction assembly 150 is positioned adjacent the registration rail 105 to apply a drag force to adjacent aligned document edges. In this manner, the drag force is applied at a point spaced from the centerline of the document 20 on the same side as the driving force applied by the separating mechanism 180 . Thus, from the perspective of FIG. 5, the drag force generated by the skew reduction assembly 150 applies a counterclockwise torque to the document 20, while the drive force generated by the separation mechanism 180 applies a clockwise torque to the document 20. In this manner, the skew reduction assembly 150 applies a torque to the document 20 in an opposite direction to the torque applied by the separating mechanism 180 .

[0060] With reference to FIG. 4, further details of the skew reduction assembly 150 are provided. The skew reduction assembly 150 includes a weighted blocking mechanism 155 that rests on top of the stack of documents 20 . The weighted blocking mechanism 155 is comprised of a block of material that adds a desired weight to a stack of documents 20 . The entire block may be made from a high friction material. However, in this embodiment, a high friction pad 157 is applied to the bottom surface of the weighted blocking block 155 . High friction generally means having a higher coefficient of friction than standard paper. For example, the coefficient of friction is greater than 0.5. Optionally, the coefficient of friction may be greater than 0.75 and greater than 1.0.

[0061] The weighted blocking block 155 is movable between a raised position and a lowered position. And, in this raised position, the weighted blocking mechanism 155 has been moved above the paper path such that the weighted blocking block 155 is positioned above the drop conveyor 100 and above the documents in the pre-feed assembly 120 . Also, in the lowered position, the weighted blocking block 155 is positioned above the document stack. Optionally, in this lowered position, the weighted blocking block 155 may be spaced apart from the surface of the conveyor 120, forming a gap between the drop conveyor 100 and the bottom surface 157 of the weighted blocking block 155, as shown in FIG. 4. The gap in the lowered position is large enough to allow a single sheet of paper to pass through the weighted blocking block 155 without contacting it. Optionally, the gap is large enough to allow a thin document stack (such as a document stack containing a few sheets of paper) to pass through without contacting the weighted blocking block 155 .

[0062] The weighted blocking mechanism 155 is movable between a raised position and a lowered position by the mounting arm 152 . In this embodiment, the mounting arm 152 is connected to the first pre-feed assembly 130 and optionally also to the second pre-feed assembly 140, so that when the first pre-feed assembly 130 and / or the second pre-feed assembly 140 move, the mounting arm 152 also moves.

[0063] The skew reduction assembly 150 may be configured to engage the trailing end of the document stack when the leading end of the document stack is located at the separation mechanism 180 . In this manner, the skew reduction assembly 150 acts on the document stack at a location spaced rearward from the longitudinal midpoint of the document stack.

[0064] The mounting arm 152 may be an elongated arm extending rearwardly from the first pre-feed assembly 130 . Optionally, the mounting arm 152 may extend rearwardly to position a weighted blocking mechanism 155 above the drop conveyor 100 . The mounting arm 152 may extend inwardly toward the alignment rail 105 such that the weighted blocking mechanism 155 is positioned adjacent to the alignment rail 105 .

[0065] Weighted blocking mechanism 155 may be fixedly or pivotally connected to mounting arm 152 such that as mounting arm 152 moves up and down, weighted blocking mechanism 155 also moves up and down. Alternatively, the weighted blocking mechanism 155 may be removably connected to the mounting arm 152 . For example, as shown in FIG. 2, a lift tab 158 may project outwardly from the body of the weighted blocking mechanism 155 . A lift tab 158 may be located on the end of the mounting arm 152 such that the lift tab 158 is positioned opposite the mounting arm 152 . Thus, when the mounting arm 152 is lifted upward, it engages the lift tab and lifts the weighted blocking mechanism 155 . Conversely, when the mounting arm 152 moves downward, the weight of the weighted blocking mechanism 155 causes the weight to move downward while resting on the end of the mounting arm 152 . However, when the lower surface 157 of the weighted blocking mechanism 155 engages the top of the document stack, the tab disengages from the mounting arm 152 as it moves downward.

[0066] The skew reduction assembly 150 may also include a track 159 for guiding the weighted blocking mechanism 155 as it moves vertically. For example, with reference to FIG. 5 , the track 159 may include a vertical path and the weighted blocking mechanism 155 may include a flange that protrudes into the vertical path to guide vertical movement of the weighted blocking mechanism 155. [Image source]

[0067] From the drop-off point 110, the documents enter the image capture point 200 where the documents are scanned to obtain image data for each document. The image capture device preferably includes a pair of scanners 210 for scanning both sides of a document. In particular, the image capture device 200 preferably includes a lower plate on which a lower scanner 210 is disposed, and an upper plate on which an upper scanner is disposed. The lower scanner 210 scans the bottom side of the document and the upper scanner scans the top side of the document.

[0068] The scanner may be black and white or grayscale, however, preferably scanner 210 is a color scanner. More specifically, scanner 210 is preferably a contact image sensor (CIS) module comprised of an array of photodiodes acting as the scanning elements and an LED light source.

[0069] 6-8, details of the image acquisition station 200 are shown. As previously mentioned, the image acquisition station 200 may include an upper scanner and a lower scanner. The detailed configuration of the upper and lower scanners are substantially the same, except that the upper scanner is inverted relative to the lower scanner. Therefore, in the following description, only one scanner is shown and described. It should be understood that the scanner descriptions apply to both the upper and lower scanners 210 .

[0070] The scanner / image capture assembly 210 includes an elongated housing 215 that extends across the width of the document path. The length of the housing 215 is equal to or greater than the width of the widest document that will be processed by the scanner 210 . Additionally, the housing 215 is generally box-shaped and open-topped. A glass cover or lens 230 extends across the open top surface of the housing 215 . A contact image sensor PCB circuit (CIS) 220 is disposed on the bottom of the housing 215 . The CIS is comprised of a series of elements that extend along the length of the housing 215, with the CIS extending across the width of the paper path. In this manner, the image capture sensor can capture image data across the width of the paper path. A plurality of light elements 225 provide illumination to illuminate documents passing through the CIS.

[0071] The image acquisition station 200 may optionally include a roller assembly 250 that faces the scanner 210 . The roller assembly 250 is configured to have a background surface for the document and one or more drive rollers to prevent the document from jamming or folding as it passes between the scanner 210 and the background surface.

[0072] The roller assembly 250 also includes a roller housing 260 that overlies a pair of rollers, a leading roller 270 and a trailing roller 275 . The roller housing 260 and rollers 270 , 275 extend across the width of the paper path and are substantially the same width as the scanner 210 . The rollers 270, 275 are spaced apart from one another by a gap. Specifically, the gap between rollers 270 , 275 is wider than the field of view of scanner 210 , and rollers 270 and 275 are located outside the field of view of scanner 210 . The ends of each roller 270, 275 are supported by end brackets 265 which keep the rollers 270, 275 parallel and properly spaced from one another. Optionally, as shown in FIG. 6, rollers 270, 275 may be operatively connected by a timing belt or the like such that rollers 270, 275 are driven synchronously. For example, as described further below, the rollers 270, 275 may be driven synchronously in a clockwise direction as viewed from the perspective of FIGS.

[0073] The roller assembly 250 is biased toward the top surface of the scanner 210 . The end bracket 265 may be configured such that the rollers 270 , 275 are spaced from the top surface 230 of the scanner 210 when the end bracket 265 is in contact with the top surface 230 of the scanner 210 . The gap formed between the rollers 270, 275 and the scanner surface 230 is shown at 235 in FIG. This gap 235 is preferably larger than the thickness of a standard gauge paper. For example, the height of the gap 235 may be 0.020 inches.

[0074] The image sensor 220 of the scanner 210 faces upward into the gap between the leading roller 270 and the trailing roller 275 . In other words, the rollers 270 , 275 straddle the field of view of the scanner 210 . In this manner, the inner surface 262 of the roller housing 260 provides a background for the scanner 210 . The inner surface 262 is configured to significantly reduce light that is reflected towards the image capture array. For example, the interior surface 262 may be constructed of a substantially light-absorbent surface, such as flat black. Additionally, the inner surface 262 may be covered with a light absorbing finish, such as flocking. In this manner, as the document passes between roller assembly 250 and image capture assembly 210, the portions of housing 260 that are not covered by the document are scanned as substantially black. Therefore, an image processor can identify document edges and process image data using the dark black edges as document edge indicators. Similarly, the gaps between successive documents do not cover the guide members, so that the leading and trailing edges of the documents appear substantially black.

[0075] As previously mentioned, the rollers 270 , 275 are spaced apart from the scanner surface 230 . As such, rollers 270, 275 do not form a nip mechanism to feed the document into the scanning station. Instead, rollers upstream of the scanner 210 pinch the document and provide the drive to feed the document into the scanning station. Similarly, nip rollers downstream of the scanner 210 engage each document and provide the driving force that moves the document away from the scanning station.

[0076] Rollers 270 , 275 do not provide a forward driving force, but rather selectively guide the document into a gap 235 between rollers 270 , 275 and scanner 210 . Specifically, rollers 270, 275 rotate clockwise when viewed from the perspective of FIG. If the document is substantially flat, it may pass through gap 235 and over scanner 210 . In such a case, the rollers 270, 275 may not engage the document.

[0077] In contrast, if the document is creased or folded, the leading edge of the document may protrude upward beyond the upper limit of gap 235 . In such a case, leading roller 270 engages the leading edge of the document and guides it downward toward upper surface 230 of scanner 210 . In this manner, the tip is guided through the gap 235 . Similarly, after passing through the field of view of the scanner 210 , the tip may be bent or creased and may protrude upward beyond the height of the gap 235 . In such a case, trailing roller 275 guides the leading edge downward through gap 235 . Once the leading edge is cleared from gap 235 by trailing roller 275 , the leading edge of the document engages the downstream nip roller and the document is pulled through gap 235 and onto scanner surface 230 . [Sorting area]

[0078] As shown in FIGS. 9-12, documents are transported from the scanning station 200 to a sorting station 300. Sorting station 300 includes a number of sorting bins 400, 402, 404, 406, 408 for receiving scanned documents. Alternatively, the document may be scanned into the bypass path and deposited in the bypass bin 410 .

[0079] A document path extends from the scanning station 200 to the sorting bins 400 through 408. In this embodiment, the document path curves upwards, feeding the document along a vertical path 310 . The vertical path 310 leads to a number of sorting paths 340, each of which leads to one of the bins 400-408. As shown in Figures 9-10, the vertical path 310 includes a series of opposed rollers 320 forming a drive nip mechanism along the length of the path. Further, as shown in Figures 11-12, each roller 320 includes multiple rollers spaced across the width of the document path such that the vertical path 310 engages the document across its width to feed the document forward.

[0080] Various sorting criteria or techniques may be used to sort the documents into the different bins 400-410. For example, documents may simply be sorted into the top bin 408 and when this bin 408 is full, they are sent to the next bin, such as bin 406. In this manner, documents may be sorted from the top bin onwards, with documents being fed into a bin and when the bin is full, the documents are sorted into the next bin. Alternatively, documents may be sorted into one of the bins based on a characteristic of the document. For example, documents with a thickness above a certain threshold may be sent to a bypass bin 410 . Similarly, documents identified as a first type of document may be sorted into bin 400 and documents identified as a second type of document may be sorted into bin 402 . The document type of a document may be determined based on physical characteristics of the document, such as length, thickness, width, etc. Alternatively, the document type may be determined based on characteristics identified from the scanned image data for each document. For example, image data for each document may be processed to determine whether the document has a particular indicia present. Marked documents may be sent to a particular receptacle from receptacles 400-410.

[0081] Regardless of the sorting technique used on the stack of documents, documents identified for delivery to any of the bins 400 - 408 are delivered to the vertical path 310 . The vertical path 310 feeds the documents upwardly towards a sortation path 340 . A series of gates 330 associated with the bins 400 through 406 selectively operate to route documents to the appropriate bin. Specifically, each gate 330 is movable between a first position and a second position. In the first position, the gate 330 allows the document to continue along the vertical path 310 . In the second position, gate 330 redirects the document to an adjacent sortation path 340 .

[0082] Each sort path 340 optionally includes an entrance nip mechanism 342 formed by a pair of opposed rollers. Additionally, each sorting path 340 includes an output nip mechanism 345 formed by a pair of opposed rollers. As previously described for rollers 320 of vertical path 310, the rollers of entrance nip mechanism 342 and exit nip mechanism 345 are a series of opposed rollers that extend across the width of the paper path.

[0083] The entrance nip mechanism 342 and the exit nip mechanism 345 are interconnected to the vertical drive rollers 320 such that the rollers of the sort path 340 may also be driven by the vertical path 310 . However, in this embodiment, one or more rollers in each sort path 340 are provided with individual drives. For example, with reference to FIG. 11, sorter 300 optionally includes a first motor 370 that drives vertical path 310 . Additionally, sorting apparatus 300 optionally includes one or more individual motors for driving one or more rollers in sorting path 340. For example, sorter 300 may include a first sort path motor 360 for driving first sort path 340 to bins 400 . Similarly, the sorting apparatus 300 may include individual motors 402 , 404 , 406 , 408 for each sorting path 340 of the bins 402 , 404 , 406 , 408 .

[0084] Each individual sort path drive motor 360 - 368 may be interconnected with all of the rollers in each sort path 340 . As shown in FIG. 10, in this embodiment, each sort path motor 360 - 368 is directly connected only to the discharge nip mechanism 345 of its respective sort path 340 . For example, the sort path 340 leading to the sort bin 402 includes a discharge pinch mechanism 345 . The sort path drive motor 362 directly drives the drive roller shaft of the discharge nip mechanism 345 . Thus, operation of the sort path drive motor 362 controls operation of the discharge nip mechanism 345 . Additionally, the entrance clamp mechanism 342 to the sort path 340 is optionally connected to a vertical path drive motor 370 . For example, a drive belt interconnects the drive rollers of the entrance pinch mechanism 342 with the rollers 320 of the vertical path 310 . In this manner, the entrance pinch mechanism 342 is driven at the same speed as the vertical path 310 and is controlled by the operation of the vertical path drive motor 370 .

[0085] Sorting station 300 includes a number of sensors that detect the presence of documents. For example, sortation station 300 may include multiple infrared sensors across the pathway. In such an embodiment, an infrared emitter is located on one side of the document path and an infrared detector is located on the opposite side of the document path. As the document passes the sensor, it obstructs the detector and a signal is provided indicating the presence of the document. Central controller 90 controls the various operations of sorter 300 in response to signals received from the sensors. The sensors are positioned at various locations along the document paths, including the vertical path 310 and the sorting path 340 . It should also be appreciated that at each location along the path where a sensor is located, the sensor may be an assembly including multiple sensors extending along the width of the document path. For example, with reference to FIG. 11, sensor 325 is a PCB assembly that spans the width of the document path and has multiple sensors spaced apart along the length of the PCB assembly.

[0086] Additionally, the document processing system may include one or more sensors that detect the movement of documents along the sortation path 340 . For example, with reference to FIG. 10, each sort path 340 may include one or more sensors 350 that detect the presence of documents. The sensor 350 may be located anywhere along the sort path 340 or may be located along the vertical path 310 . In some applications, signals from a document sensor 325 in the sorting path 340 can be used to control the document as it passes through both the vertical path 310 and the sorting path 340, as described below.

[0087] In this embodiment, the sensor 350 is disposed adjacent to the discharge pinch mechanism 345 and is disposed upstream of the discharge pinch mechanism 345 . In this manner, the sensor 350 detects the leading edge of each document before it enters the output nip mechanism 345 . In addition, a sensor 350 detects the trailing edge of each document before it enters the output nip mechanism 345 .

[0088] Since the distance between the sensor 350 and the discharge clamping mechanism 345 is a predetermined distance, the time from when the leading edge of the document is detected by the sensor 350 to when it enters the discharge clamping mechanism 345 can be determined based on the moving speed of the leading edge of the document after it passes the sensor. Similarly, the time between when the trailing edge passes sensor 350 and when it enters output nip mechanism 345 can be known based on the speed at which the document moves after passing sensor 350 .

[0089] For example, as the document moves along the output path 340 upstream of the output nip mechanism 345, the document may move at a first speed that is the same as the speed at which it moves along the vertical path 310, as described further below. When the document passes the sensor 350, the time it takes to enter the output nip mechanism 345 is known based on the distance between the sensor 350 and the output nip mechanism 345 and the first speed.

[0090] As the document enters the output nip mechanism 345 , the velocity of the document may be controlled by the output nip mechanism 345 . The velocity of the document may be selectively increased or decreased by the exit nip mechanism 345 . For example, as the leading edge enters the output nip 345, the speed of the output nip 345 may increase to a second speed and the output nip 345 may function as a tension nip, pulling the document through the entry nip 342, which continues to operate at the first speed. Similarly, the output nip mechanism 345 may reduce the speed of the document to a third speed that is slower than the second speed and optionally slower than the first speed. The timing of speeding up and / or slowing down the document as it passes through the output nip mechanism 345 may be controlled based on the signal received by the sensor 350 .

[0091] 13-14, the system may optionally incorporate one or more elements that corrugate documents to facilitate stacking of the documents in sorting bins 400-408. Document stacking tends to be improved if the documents are corrugated as they are discharged into the container.

[0092] With reference to FIG. 13, the discharge nip mechanism 345 includes a plurality of upper rollers 348 mounted on an axle 349 . The upper rollers 348 are spaced apart along the length of an axis 349 and extend across the width of the document path. Similarly, the discharge nip mechanism 345 also includes a plurality of lower rollers 346 mounted on an axle 347 . The lower rollers 346 are spaced apart along the length of an axis 347 and extend across the width of the document path. In this embodiment, the lower roller 346 is a drive roller and the upper roller 348 is a driven roller. Specifically, shaft 347 may be directly connected to one of the sort path motors 360-368.

[0093] As shown in FIG. 13, a plurality of corrugated elements 380 may be disposed in the gap between the upper roller 346 and the lower roller 348 along the length of the shafts 347, 349. The corrugated elements 380 project above the upper surface of the lower roller 346 . In this manner, the corrugated element 380 pushes the document 20 upward while the output nip mechanism 345 holds a portion of the document underneath. In this manner, the corrugation element 380 creates corrugations in the document 20 as it is ejected through the ejection nip mechanism 345 .

[0094] In this embodiment, the corrugated element 380 has a variable corrugation force. Specifically, the height to which the corrugated elements 380 project above the paper path varies. For example, the height to which the corrugated elements 380 protrude upwardly may vary based on the thickness of the document. More specifically, the distance that the corrugated elements 380 protrude above the paper path is optionally inversely proportional to the thickness of the document.

[0095] With reference to FIG. 14, the corrugation elements 380 may be elongated finger-like members 380 that project upwardly at an angle relative to the paper path. Finger 380 may be a pivotable lever that pivots about pivot point 382 . The fingers 380 may be biased upwardly. Specifically, the rear end of finger 380 may be connected to a biasing element 384 that biases the rear end of finger 380 downward, thereby biasing the upper end of finger 380 upward. As the document moves over the fingers 380, the fingers 380 push the paper upwards causing the paper to corrugate. The document presses against finger 380, forcing finger 380 downward against the bias of the spring. The amount of force that the document exerts on the finger 380 increases with the thickness of the document. In this manner, the corrugated elements 380 will protrude upwardly less for a thicker document than for a thinner document. Thus, the height of the corrugations varies depending on the thickness of the document, with thicker documents having shallower corrugations than thinner documents. [How to use]

[0096] The workstation 10 and sortation station 300 may be used for a variety of document processes using a variety of document processing flows. The combination of workstation 10 and sortation station 300 provides alternative process flows that can be used for a variety of document batches. For example, the initial document batch may be a stack of documents in the form of contents removed from an envelope. For such jobs, an operator may input information into the system indicating that the documents for that job are to be scanned by scanner 60 and sorted into output bin 70 .

[0097] It will be appreciated that the image processor 90 of the system is operable to process image data acquired by the scanner 60 from the document. Specifically, image processor 90 is capable of processing data to identify and read indicia on a document. For example, image processor 90 may use OCR to identify characters such as a recipient's address printed on a document. Similarly, image processor 90 may identify and read indicia such as bar codes. The identification indicia can be used to control the processing of documents at sorting station 300, as previously described.

[0098] Optionally, sorting station 300 may be operated so that documents within sorting bins 400-408 are neatly stacked. For example, the vertical path 310 may move at a set speed. By way of example, a speed of 50 to 70 inches / second (or 125 to 175 cm / second) may be used. In particular, the orbital velocity may be about 60 inches / second (or 150 cm / second). However, there are times when it is desirable to eject documents at a very slow trajectory speed so that the documents are ejected slowly into the sorting bins and neatly stacked. As an example for ejecting documents at slow trajectory speeds, the starting speed may be approximately 15 to 30 inches / second (or 35 to 75 cm / second). In particular, the discharge velocity may be about 20 inches / second (or 50 cm / second).

[0099] Slowing down the document as it is ejected can cause problems upstream with subsequent documents. Specifically, slowing down the speed of the trajectory along which the documents are discharged may cause upstream documents to become jammed. Therefore, it may be desirable to provide some distance between the ejected document and any subsequent documents. This distance is achieved by significantly increasing the speed of the sort path 340 before the documents are ejected, and then slowing the documents down as they are ejected. For example, the document speed may be increased to approximately 120 to 150 inches / second (or 300 to 375 cm / second). An example of a fast speed is a speed of 135 inches / second (or 340 cm / second).

[0100] In an exemplary method, the document is transported along a vertical transport at a first speed (eg, 60 inches / second). The document is sent to one of the sorting paths 340 . For example, gate 330 may selectively route documents to a first sortation path 340 . In the sort path 340, the document path speed may be increased to a second speed (eg, 135 inches / second) for a period of time or until the document has traveled a certain distance. Before the trailing edge of the document enters the output nip mechanism 345, the document path speed may be reduced to a third speed (eg, 20 inches / second) slower than the first and second speeds. After the trailing edge of the document passes through the output nip mechanism 345 , the document path speed may be increased to a first document path speed such that the document path speed of the sort path 340 matches the document path speed of the vertical path 310 .

[0101] More specifically, the entrance nip mechanism 342 of the vertical path 310 and sorting path 340 may operate at a relatively constant speed, while the speed of the exit nip mechanism 345 may vary depending on the location of the document being sorted. For example, the document may be transported at a track speed (eg, 60 inches / second) as it is transported by the vertical path 310 and the entrance nip mechanism 342 . The document continues to be transported at orbital speed until it engages the exit nip mechanism 345 . As the document enters the output nip 345, the motor 360 increases the speed of the output nip rollers 345 (e.g., 135 inches / second) so that the output rollers pull the document through the output nip 345, increasing its speed relative to subsequent documents in the vertical path 310 and widening the gap between the document and the subsequent documents. The output nip mechanism 345 operates at its elevated speed until the majority of the document has passed the output nip mechanism 345 . The speed of the motor 360 is then significantly reduced (eg, 20 inches / second) to move the trailing edge of the document slowly past the exit nip 345 . In this manner, the documents are discharged at a slower rate and neatly stacked within the sorting bin 400 . The motor 360 is then again increased in speed to drive the ejection pinch mechanism 345 at an orbital speed (eg, 60 inches / second).

[0102] The timing of the speed change may be controlled based on one or more sensors 325, 350 that detect the presence of a document. For example, a sensor 325 located in the vertical path 310 just prior to the sorting path 340 through which the documents are fed may be used to control the transport speed of the documents. For example, a document may be driven at a first speed (eg, 60 inches / second) as it is fed along the document path to the sortation path 340 . After the document passes a sensor 325 adjacent the sorting path 340, the sensor 325 detects the trailing edge of the document. Upon detecting the trailing edge of the document, a timer is started to control the speed of the output nip mechanism 345 . Specifically, when the trailing edge of the document is detected, the speed of the output nip mechanism 345 increases to an increased speed (e.g., 120 inches / second) for a specific predetermined time corresponding to the time it takes for the leading edge of the document to travel from the sensor 325 to the output nip mechanism 345 when moving at transport speed. The discharge pinch mechanism 345 is driven at this elevated speed for a predetermined period of time. In particular, this predetermined time may be the time it takes for the trailing edge to travel from the discharge pinch mechanism 345 to a predetermined point upstream. For example, it may be the time it takes for the trailing edge to move from the sensor 325 to one inch before the ejection pinch mechanism 345. After a predetermined time has elapsed, the motor 360 slows down to a slower speed (eg, 20 inches / second) long enough to allow the document to be ejected past the ejection nip 345 and into the bin 400 . After this time has elapsed, the speed of the output nip mechanism 345 increases to the transport speed.

[0103] Changes and modifications may be made to the embodiments described above without departing from the broad inventive concept of the present invention. It is intended, therefore, that this invention not be limited to the specific embodiments described herein, but that it includes all changes and modifications included within the scope and spirit of the present invention as defined by the appended claims.

Claims

1. a scanner for scanning a stack of documents to obtain image data of each document; a conveyor for transporting the stack of documents to the scanner, the conveyor being configured to transport the stack of documents in a substantially horizontal direction with the stack of documents facing upward; a feeder configured to feed the documents in the stack from the conveyor to the scanner, the feeder configured to separate and sequentially feed the documents to the scanner; a skew reduction assembly disposed upstream of the feeder to prevent the document from rotating about a vertical axis as the feeder feeds the document; The document processing device comprises:

2. the feeder providing a net forward force to a first side of the document at a point spaced laterally from a centerline of the document; 2 . The document handling device of claim 1 , wherein the skew reduction assembly provides a resistance force to the first side of the document in a direction opposite to the net forward force at a location spaced from the centerline of the document.

3. 3. The document handling device of claim 2, wherein the skew reduction assembly includes a weight configured to rest on a trailing portion of the document stack while the feeder engages a leading portion of the document stack.

4. the document stack having a length, the trailing end portion of the document stack includes a portion rearward of the midpoint of the length, 4. The document processing device of claim 3, wherein said leading edge portion includes a portion forward of said center point.

5. 4. The document handling system of claim 3, wherein said weight has a high friction surface for engaging a top document of said stack.

6. 2. The document processing device of claim 1, further comprising a sensor for detecting a characteristic of said document stack, and a controller for selectively controlling said deskew reduction assembly in response to a signal from said sensor.

7. the characteristic is indicative of a thickness of the document stack, 7. The document processing device of claim 6, wherein the controller is configured to operate the skew reduction assembly in response to a signal from the sensor indicating that the thickness of the document stack is below a threshold value.

8. the skew reduction assembly having a movable arm; 2. The document handling device of claim 1, wherein the movable arm is selectively operable to move the skew reduction assembly into engagement with the document stack or out of engagement with the document stack.

9. 1. A document processing method comprising: feeding the document in a first direction along a document path by applying a feeding force that creates a torque in the first direction to a leading edge portion of the document at a location spaced from a centerline of the width of the document; applying an anti-skew force to the trailing portion of the document while the feed force is being applied to the leading portion of the document, the anti-skew force being applied in a direction opposite to the direction of the feed force and at a location spaced from the centerline of the document widthwise; A document processing method comprising:

10. said step of sending said document includes sending said document to a scanner; 10. The document processing method of claim 9, further comprising the step of scanning the documents, the step of scanning the documents to obtain image data for each document indicative of an image of the document.

11. 10. The method of claim 9, further comprising the step of conveying the document in a generally horizontal direction toward the feeder with the document facing up.

12. 12. The method of claim 11, wherein the step of transporting the document in a generally horizontal direction toward the feeder includes engaging a bottom surface of the document without engaging the top surface of the document.

13. 10. The method of claim 9, wherein the leading edge portion is forward of the midpoint along the length of the document.

14. 10. The method of claim 9, wherein the trailing portion is behind the midpoint along the length of the document.

15. 10. The method of claim 9, wherein the step of feeding the document includes the step of applying the feeding force to a first side of the document widthwise centerline.

16. 10. The method of claim 9, wherein the step of applying the anti-skew force includes applying the anti-skew force on the first side of the centerline across the width of the document.

17. 17. The method of claim 16, wherein the step of applying the counter-skew force includes applying a force normal to the first side of the widthwise centerline of the document.

18. 20. The method of claim 17, wherein the step of applying a normal force comprises the step of applying a weight to the document.

19. the document is part of a document batch; 20. The method of claim 18, wherein the step of applying weights to the documents includes applying the weights to the top of the document stack.

20. 20. A method of document processing as claimed in claim 18 or claim 19, including the step of selectively lifting said weights to eliminate said counter-skew forces.

21. 10. The method of claim 9, wherein the step of applying the anti-skew force includes the step of selectively applying the anti-skew force in response to a characteristic of the document.

22. 22. A method for processing documents as recited in claim 21, wherein the counter-skew force is applied in response to detecting that the document is part of a stack of documents having a thickness exceeding a threshold value.

23. 23. A method as recited in claim 22, wherein the counter tilt force is not applied upon detecting that the document is a single document or part of a stack of documents having a thickness below the threshold.

Images