Abstract:
An item handling system includes a vacuum source, a transport element defining a plurality of vacuum openings in fluid communication with the vacuum source to create a securing force on an item proximate to the transport element for holding the item in contact with the transport element, and a drive element for driving the transport element to transport the item. The transport element further defines a plurality of sensor openings arranged in two substantially parallel arrays along a longitudinal direction of the transport element. The system further includes a sensor associated with each array of sensor openings for sensing energy passing through the sensor openings to thereby sense the item on the transport element. Each sensor is disposed at a common longitudinal position relative to the transport element. Sensing the item corresponds to a condition where the sensor associated with each array is blocked.

Description:
CROSS REFERENCE TO RELATED APPLICATION 
       [0001]    This application is a Divisional Patent Application of prior application Ser. No. 12/613,085, filed Nov. 5, 2009, entitled “Item Handling System with Tracking” which application is hereby incorporated by reference in its entirety. 
     
    
     FIELD OF THE INVENTION 
       [0002]    The invention relates to system and method for handling items and, more particularly, to an item handling system having the capability to track items in the system. 
       BACKGROUND OF THE INVENTION 
       [0003]    Item handling systems, such as mail piece handling systems, for example, are known in the art. These systems include inserter systems, sortation systems, and document transports. Inserter systems generally create mail pieces and prepare them for mailing. Sortation systems sort completed mail pieces by a designated parameter, such as delivery address, for example, and deposit the mail pieces in a respective pocket or bin. Document transports move documents between processing devices. Other types of item handling systems and related applications are known. 
         [0004]    In some handling systems, documents are transported using belts or chain drives between stations where they undergo various types of processing. The processing may include cutting, folding, scanning, weighing, printing, and labeling, for example. 
         [0005]    Some of the processing steps require that a document be maintained in a particular orientation or at a particular distance from a processing element. In one example, a scanning device may require a particular alignment or offset distance between the document and the device. In another example, certain printing devices, such as inkjet printers, for example, require a constant offset with respect to the document to ensure printing integrity. 
         [0006]    In addition, many of the processing steps require precise knowledge of the location of the document. For example, labeling devices and/or printers require information regarding a document&#39;s location in order to apply a label or an image in a desired location on the document. 
         [0007]    In those cases, the control of the document provided by the transport belts or chains may affect the ability to properly orient and register the document for processing. Moreover, conventional sensors for determining a document&#39;s location may require the use of transport systems that provide holding forces that are insufficient to properly maintain documents on the transport element during transport. 
       SUMMARY OF EXEMPLARY ASPECTS 
       [0008]    In the following description, certain aspects and embodiments of the present invention will become evident. It should be understood that the invention, in its broadest sense, could be practiced without having one or more features of these aspects and embodiments. It should also be understood that these aspects and embodiments are merely exemplary. 
         [0009]    In accordance with the purpose of the invention, as embodied and broadly described herein, one aspect of the invention relates to an item handling system comprising a vacuum source, a transport element, and a drive element for driving the transport element to transport the item. As used herein, “items” include papers, documents, postcards, brochures, enclosures, booklets, magazines, and media items, including CDs, DVDs, computer disks, and/or other digital storage media. 
         [0010]    The transport element may define a plurality of vacuum openings in fluid communication with the vacuum source to create a securing force on an item proximate to the transport element for holding the item in contact with the transport element. The transport element may further define a plurality of sensor openings arranged in two substantially parallel arrays along a longitudinal direction of the transport element. 
         [0011]    The item handling system may further comprise a sensor associated with each array of sensor openings for sensing energy passing through the sensor openings to thereby sense the item on the transport element. Each sensor may be disposed at a common longitudinal position relative to the transport element. Sensing the item may correspond to a condition where the sensor associated with each array is blocked. 
         [0012]    In another aspect, the invention relates to a method of handling an item, comprising placing a plurality of vacuum openings of a transport element in fluid communication with a vacuum source to create a securing force on an item proximate to the transport element for holding the item in contact with the transport element. The transport element may further define a plurality of sensor openings arranged in two substantially parallel arrays along a longitudinal direction of the transport element. 
         [0013]    The method may further comprise driving the transport element with a drive element to transport the item and sensing energy passing through the sensor openings using a sensor associated with each array to thereby sense the item on the transport element. Each sensor may be disposed at a common longitudinal position relative to the transport element. Sensing the item may correspond to a condition where the sensor associated with each array is blocked. 
         [0014]    Aside from the structural and procedural arrangements set forth above, the invention could include a number of other arrangements, such as those explained hereinafter. It is to be understood that both the foregoing description and the following description are exemplary only. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0015]    The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate exemplary embodiments of the invention and, together with the description, serve to explain the principles of the invention. In the drawings, 
           [0016]      FIG. 1  is a schematic view of an apparatus comprising features of the invention; 
           [0017]      FIG. 2  is a top plan view of a portion of the item transport system shown in  FIG. 1 ; 
           [0018]      FIG. 3  is a side view of the portion of the item transport system shown in  FIG. 2 ; 
           [0019]      FIG. 4  is a schematic view of several components of the item transport system shown in  FIG. 2 ; and 
           [0020]      FIG. 5  is a top plan view of the transport element shown in  FIGS. 2-3 . 
       
    
    
     DETAILED DESCRIPTION OF EXEMPLARY EMBODIMENTS 
       [0021]    Reference will now be made in detail to exemplary embodiments of the invention, examples of which are illustrated in the accompanying drawings. Wherever possible, the same reference numbers will be used throughout the drawings to refer to the same or like parts. 
         [0022]    Referring to  FIG. 1 , there is shown a diagram illustrating an apparatus  40  incorporating features of the invention. Although the invention will be described with reference to the example embodiment shown in the drawings, it should be understood that the invention can be embodied in many alternate forms of embodiments. In addition, any suitable size, shape, or type of elements or materials could be used. 
         [0023]    In the illustrated embodiment, the apparatus  40  comprises an inserter configured to insert mail pieces, e.g., documents, into envelopes. As discussed above, embodiments of the invention may be used with a range of other items. Accordingly, the term “documents” is used interchangeably with “items” herein. Moreover, embodiments of the invention may also have applications in mail and document handling devices additional to inserters. 
         [0024]    The inserter  40  generally comprises document supply units  42 , an insertion station  44 , an envelope supply unit  46 , an item transport system  48 , and an output  50 . The document supply units  42  can each hold a supply of similar or dissimilar documents  16 . In some embodiments, the supply may be arranged as a stack. The documents  16  may be mail piece inserts or mail piece documents, for example. 
         [0025]    The item transport system  48  is adapted to transport documents from the document supply units  42  to the insertion station  44  for insertion into an envelope at the insertion station  44 . In one embodiment, the assembly of the documents from each of the document supply units  42  into a stacked assembly occurs on the item transport system  48 . After the documents are inserted into the envelope at the insertion station  44 , the envelope is then sent to the output  50 . 
         [0026]    Referring also to  FIGS. 2-5 , the item transport system  48  includes a printing system for personalizing at least one of the documents from the document supply units  42  before insertion into the envelope at the insertion station  44 . The item transport system  48  comprises a vacuum source  22 , a transport element  52 , rollers  18 ,  19 , a print head  24 , through beam detectors  54 / 56 , and a controller  58 . The transport element  52  may comprise a belt comprising a variety of materials and having a range of surface finishes. Examples of belt materials include fabrics, rubber and/or other synthetic compounds, and combinations thereof. Other transport elements may also be used. Accordingly, the term “belt” is used interchangeably with “transport element” herein. 
         [0027]    One or both of the rollers  18 ,  19  are driven by a drive element, identified as a belt drive  23  in  FIG. 4 . The belt drive  23  may comprise a motor or other drive element. 
         [0028]    As seen best in  FIG. 5 , the belt  52  is a one-piece continuous belt defining a plurality of openings. The openings comprise vacuum openings  60  and sensor openings  62 . The vacuum openings  60  extend across substantially the entire width and length of the belt  52 , such as arranged in an array of rows across the width  64  and columns along the length. The first run  66  of the belt  52 , between the rollers  18 ,  19 , is located against the top of the deck  21  in sliding engagement. The belt  52  is in fluid communication with the vacuum source  22  to allow a vacuum holding force against the document  16  through the vacuum openings  60  to hold the document  16  against the top side of the belt  52 . 
         [0029]    The sensor openings  62  are larger than the vacuum openings  60  and have an elongate, i.e., oblong shape. The sensor openings  62  are intermixed among at least some of the vacuum openings  60 . In this embodiment, the sensor openings  62  are arranged in two arrays  68 ,  69  along the longitudinal length of the belt  52 . The leading edges  70  of the sensor openings  62  in the first array  68  are longitudinally offset  71  relative to leading edges  70  of the sensor openings in the second array  69 . Due to the arrangement of the two arrays  68 ,  69 , there is always at least one of the openings  62  at any single length of the belt  52 , so at least one of the detectors  54 / 56  is always aligned with one of the openings  62 . 
         [0030]    In this embodiment the sensor openings  62  are spaced inward from outer lateral edges  72  of the belt  52 . The two arrays form a first column of the sensor openings adjacent a second column of the sensor openings, wherein the second column of sensor openings is partially longitudinally offset from the first column of sensor openings. 
         [0031]    The detector  54 / 56  is a through beam sensor, generally comprising at least one energy transmitter  54  and at least one sensor  56 . The respective transmitters  54  are disposed on opposite sides of the belt  52  relative to the corresponding sensors  56 . In this embodiment, the transmitters  54  are located in the area  74  between the first and second runs of the belt  52 , and the sensors  56  are located above the top side of the belt  52  at the first run  66 . The first and second runs of the belt correspond to top and bottom runs, respectively, because the item transport system  48  is shown in a horizontal arrangement in the drawings. Other arrangements may also be used. 
         [0032]    As illustrated best in  FIG. 2 , the detectors  54 / 56  are provided in pairs  76 . The pairs  76  are at longitudinally spaced locations along the belt  52 . In the illustrated embodiment, the transport system  48  also includes a detector  54   a / 56   a  at the second run  67  of the belt  52  (bottom, as shown in  FIG. 3 ). Thus, pairs of the detectors are located on a first run of the belt, and a pair of the detectors is located on a second run of the belt. The additional bottom side through beam photocell detector  54   a / 56   a  can sight through belt slots to track the position of the belt as it passes by, without regard for whether or not a document is located on the belt, or if the document blocks all three top detector pairs  76 . 
         [0033]    The print head  24  is configured to print on the document  16 . The document transport belt  52  is configured to move the document  16  to the print head  24 . The print head  24  is connected to the controller  58  such that the controller  58  controls printing by the print head. The detectors  54 / 56  are connected to the controller  58 . The detectors  54 / 56  are adapted to determine the location of the document  16  on the belt  52  and signal the controller  58 . The controller comprises a processor and a memory which, based upon signals from the detectors  54 / 56 , can determine when the document is located at the print head  24  for precise location printing by the print head on the document. 
         [0034]    In some applications, users of mail piece inserters may require personalization of the documents they print, insert, and mail to customers. To personalize documents, “on-demand” printing is utilized on the inserting system. According to embodiments of the invention, a vacuum transport is utilized to ensure that there is no slippage between the document and the transport. The illustrated embodiments utilize a transport having a single wide vacuum belt  52  for flexibility and design robustness, provided with through beam photocells. This arrangement may provide reliable document tracking everywhere in an inserter system. 
         [0035]    Embodiments of the invention may have applicability in a variable thickness vacuum printing base for an inserter, utilizing a full width belt and through beam sensors. Optionally, the oblong shapes of the sensor openings  62  may be slots cut in the belt at manufacture.  FIG. 2  shows a top view of a transport with slotted belt and the detectors  54 / 56  (the through beam sensors) sighting through openings in the deck  21 . 
         [0036]    In some embodiments, through beam sensor pairs  76  may be used in sets side-by-side. Because the slots  62  in the belt are staggered, one of the detectors of each pair  76  can always sight through the belt  52  and deck  21  to determine the presence or absence of a document at that location. This geometry and pairing of sensors enables use of the through beam sensors with a full width belt, which was previously unavailable. 
         [0037]    The belt  52  is configured so as not to block both of the detectors of the pair at that location simultaneously. Both detectors of the pair will be blocked only upon the arrival of the leading edge of a document on the belt  52 . The position of that leading edge may be tracked as subsequent, downstream sensor pairs  76  are blocked by the arrival of the document&#39;s leading edge. 
         [0038]    The securing force on the documents provided by the full width belt may allow improved accuracy of the text or images to be printed on the documents by the printer associated with the system. Such accuracy is more significant for color printing, as alignment among the four colors that make up the image is directly related to image quality. Thus, embodiments of the invention may provide improved document sensing using the through beam detectors, while providing secure transport of the documents using the single full width belt design. 
         [0039]    With embodiments of the invention, a method of transporting a document can be provided comprising holding the document against a belt by a vacuum force extending through multiple vacuum openings arranged across a length and a width of the belt. The method can include sensing location of the document on the belt as the document is moved by the belt. Radiant energy from the transmitters  54  can be sent towards the belt located opposite a first side of the belt. The belt can comprise sensor openings  62  which are adapted to allow the radiant energy to pass through the belt at the sensor openings. A sensor  56  on an opposite second side of the belt can sense when the radiant energy is blocked from passing through one of the sensor openings by presence of the document  16  at least partially over the blocked sensor opening. 
         [0040]    Embodiments of the invention further relate to a system, comprising a document transport belt  52  having an array of vacuum openings  60  across a width  64  and a length of the belt, wherein the belt further comprises sensor openings  62  along the length of the belt interspersed with the vacuum openings. The sensor openings  62  can comprise a first array  68  of the sensor openings and a second array  69  of the sensor openings. The sensor openings in the first array  68  are partially longitudinally offset  71  relative to the sensor openings in the second array  69 . For each of the first and second arrays of sensor openings, an energy transmitter  54  and an energy sensor  56  can be located on respective opposite sides of the belt such that energy from at least one of the transmitters can pass through at least one of the sensor openings  62  to at least one of the sensors except when blocked by a document on the belt. 
         [0041]    It will be apparent to those skilled in the art that various modifications and variations can be made to the structure and methodology described herein. Thus, it should be understood that the invention is not limited to the examples discussed in the specification. Rather, the present invention is intended to cover modifications and variations.