Patent Publication Number: US-7905076-B2

Title: Apparatus and method for conveying envelopes in a mailpiece insertion system

Description:
FIELD OF THE INVENTION 
     The invention relates to an envelope transport and, more particularly, to the feeding of envelopes to a mail piece insertion location. 
     BACKGROUND OF THE INVENTION 
     Inserter machines are used to create mail pieces for many different applications. Inserters contain a generally modular array of components to carry out the various processes associated with mail piece creation. The processes include preparing documents, assembling the documents associated with a given mail piece, adding any designated inserts, stuffing the assembly into an envelope in the envelope insertion engine, and printing information on the envelope. 
     In the inserter industry, there are generally two arrangements utilized for the envelope insertion engine: “flap-up” insertion and “flap-down” insertion. Flap-up insertion refers to an envelope orientation in which the flap of the open envelope is located above the prepared collation, which is substantially horizontal during the insertion of the collation into the envelope. The geometry of some flap-up insertion engines allows the envelope hopper to be located on the operator side of the machine without introducing the complexity and reduced reliability of a right angle turn. In other words, the envelope path from the envelope hopper to the insertion location is substantially linear. 
     However, some flap-up inserter designs require additional steps in building the collation in order to place the address-bearing document on the top of the collation. The additional steps may reduce the operating reliability of those systems. 
     Flap-down insertion refers to an envelope orientation in which the open envelope is arranged in the insertion engine with its flap located underneath a prepared collation, which is substantially horizontal during the insertion of the collation into the envelope. In flap down inserting, the address-bearing document remains on the bottom while the collation is built. That arrangement may simplify the process of building the collation. 
     In some flap-down inserter designs, however, it is necessary to utilize a more complex feed path including a right angle turn, for example, in order to locate the envelope hopper on the operator side of the machine. 
     SUMMARY OF EXEMPLARY ASPECTS 
     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. 
     In accordance with one aspect of the invention, an apparatus is provided comprising a first feed path configured to transport an envelope from an input at an envelope supply to an insertion location and a second feed path configured to transport the envelope with a mail piece insert therein from the insertion location to an output. The first feed path and the second feed path may intersect at an intersection spaced from the insertion location. 
     In another aspect, the invention relates to an apparatus comprising an envelope supply, an insertion device configured to insert a mail piece insert into an envelope while the envelope is in a flap-down position in an insertion location, and a transportation system configured to transport the envelope from the envelope supply to the insertion location with a closed end of the envelope, which is located opposite a flap end of the envelope, as a forward leading edge of the envelope. The transportation system may comprise a first feed path from the envelope supply to the insertion location and a second feed path from the insertion location to an output. The first feed path and the second feed path may intersect at an intersection spaced from the insertion location. 
     In yet another aspect, the invention relates to a method comprising transporting an envelope along a first feed path from an input to an insertion location and transporting the envelope, with a mail piece insert therein, along a second feed path from the insertion location to an output. The first feed path and the second feed path may intersect at an intersection spaced from the insertion location. 
     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 
       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, 
         FIG. 1  is a block diagram schematic of a document inserting system having an envelope insertion station according to one illustrative embodiment of the invention; 
         FIG. 2  is a side elevational view of the document inserter of the envelope insertion station shown in  FIG. 1 ; 
         FIG. 3  is a side elevational view of the envelope insertion station shown in  FIG. 1 ; 
         FIG. 4  is a partial schematic view of the envelope insertion station shown in  FIG. 3  illustrating locations of leading edges of envelopes during travel through the envelope insertion station; 
         FIG. 5  is a schematic view of the intersection of the first feed path and the second feed path; 
         FIG. 6  is a top plan view of a top side of an envelope with the flap in an open position; and 
         FIG. 7  is a diagram illustrating a method of the invention. 
     
    
    
     DETAILED DESCRIPTION OF EXEMPLARY EMBODIMENTS 
     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. 
     Envelope insertion stations are important subsystems of document inserting systems. An envelope insertion device typically inserts collated enclosures into a waiting envelope. The envelope insertion device may be used with enclosures of varying thickness and with enclosures that are not significantly different in length than the length of the envelopes into which they are inserted. 
     Some envelope insertion stations use continuously running transport belts on the deck of the insertion station, wherein the transport belts feed the envelope. Once the envelope is at an insertion position, a stop is used prevent the envelope from continuing with the belt. In one example, the transport belt slides along the underside of the envelope while the envelope is stopped by the stop. 
     Referring to  FIG. 1 , there is shown a schematic block diagram of a document inserting system  10  incorporating features of the invention. Although the invention will be described with reference to exemplary embodiments shown in the drawings, it should be understood that the invention may be embodied in many alternate forms of embodiments. In addition, any suitable size, shape or type of elements or materials may be used. The document inserting system  10  shown in  FIG. 1  includes an insertion station  100 . The document inserting system  10  is illustrative and many other configurations may be utilized. 
     The system  10  includes an input system  12  that feeds paper sheets from a paper web to an accumulating station that accumulates the sheets of paper in collation packets. In one example, only a single sheet of a collation (e.g., the control document) is coded. The coded information enables the control system  14  of the inserter system  10  to control the processing of documents in the various stations of the mass mailing inserter system. 
     The input system  12  feeds sheets in a paper path, as indicated by arrow “a”, along what is known as the main deck of the inserter system  10 . After sheets are accumulated into collations by the input system  12 , the collations are folded in a folding station  16 . The folded collations are then conveyed to a transport station  18 . In one example, the transport station  18  is operative to perform buffering operations for maintaining a proper timing scheme for the processing of documents in the insertion system  10 . 
     Each sheet collation is fed from the transport station  18  to the insert feeder station  20 . It is to be appreciated that an inserter system  10  may include a plurality of feeder stations, but for clarity, only a single insert feeder  20  is shown in  FIG. 1 . 
     The insert feeder station  20  is operational to convey an insert (e.g., an advertisement) from a supply tray to the main deck of inserter system  10  to be combined with the sheet collation conveying along the main deck. The sheet collation, along with the nested insert(s), are next conveyed into the envelope insertion station  100  that is operative to first open the envelope and then to insert the collation into the opening of the envelope. The envelope is then conveyed to a postage station  22 . Finally, the envelope is conveyed to a sorting station  24  that sorts the envelopes in accordance with postal discount requirements. 
     Referring now to  FIG. 2 , the envelope insertion station  100  according to an illustrative embodiment is shown. In operation, an envelope enters the insertion station  100  along a guide path  114  and is transported into the insertion station  100  by a set of transport rollers  116 ,  118  and continuously running transport belts  121 ,  123 ,  125 . Each transport belt  121 ,  123 ,  125 , respectively, wraps around rollers  127 ,  129 ,  131 , each roller being connected to a common shaft  133   a . Each transport belt  121 ,  123 ,  125  is juxtaposed between deck strips that form the transport deck  141  of the insertion station  100 . 
     The motion of each transport belt  121 ,  123 ,  125  is continuous for maintaining registration of an envelope  112  against a backstop  180 . Continuous vacuum from each of the deck strips via their respective vacuum plenums prevents undesirable motion of the envelope due to the transport belts  121 ,  123 ,  125  continuously running beneath. 
     In one embodiment, rotating backstop members  180  are located outside the vacuum deck strips in an elongate slot. Each backstop member  180  is concentrically mounted about a common shaft  182  for effecting rotation thereof. Each stopping portion  184  is configured to stop an envelope when it is above the deck  141  of the insertion station  100 . A servo motor (not shown) causes rotation of the backstop members  180  about an axle  182 . Other arrangements may also be used. 
     The insertion station  100  includes envelope flap retainers  124  and rotating insertion horns  126 ,  128 , each having an underside that helps to conform an envelope to each transport belt  121 ,  123 ,  125 , while not presenting any catch points for the leading edge of the enclosure collation  130  to be inserted in a waiting open envelope  112 . 
     The horns  126 ,  128  are supported from above the envelope path and are eccentrically mounted on pivot shafts  103 . They are positioned perpendicular to the path of the envelope travel as the envelope is conveyed to backstop members  180 . In some embodiments, discussed below, a vacuum assembly is used to open the envelope during insertion of the collation. Once the vacuum assembly  70  has begun to open the envelope, the insertion horns  126 ,  128  pivot into the envelope and continue their pivoting motion until the extreme edges of the envelope have been shaped and supported by the profile of each horn  126  and  128 . 
     Rotating insertion horns  126 ,  128  perform the additional function of centering the envelope  112  in the path of the oncoming enclosure collation  130 . At this time an oncoming enclosure collation  130  may be introduced and pushed through the insertion horns  126 ,  128  into a waiting envelope  112 . In one embodiment, the pivot shaft of each insertion horn  126 ,  128  is driven by a servo motor (not shown). Other arrangements may also be used. 
     The insertion station  100  further includes an envelope opening vacuum assembly  70  for separating the back panel of an envelope from its front panel. The vacuum assembly  70  is perpendicular to the transport deck  141  of the insertion station  100 . The vacuum assembly  70  includes a reciprocating vacuum cup  72  that translates vertically downward toward the surface of the transport deck  141  and then upward away from the transport deck  141  to a height sufficient to allow a stuffed envelope to pass under it. The vacuum cup  72  adheres to the back panel of an envelope through a vacuum force present in the vacuum cup  72 , so as to separate the envelope&#39;s back panel away from its front panel during the upward travel of the vacuum cup  72 . 
     The enclosure collations  130  are fed into the insertion station  100  by means of a pair of overhead pusher fingers  132  extending from a pair of overhead belts  134  relative to the deck of the inserter system  10 . As with the envelope  112 , the top side of the envelope flap retainers  124  and the associated interior of the insertion horns  126 ,  128  must not present any catch points for the leading edge of the enclosure collation  130 . 
     An envelope  112  is conveyed to the transport deck  141  of the insertion station  100  via guide path  114 , which is in connection with an envelope supply. Once a portion of the envelope  112  contacts the continuous running transport belts  121 ,  123 ,  125 , these transport belts convey the envelope  112  downstream, as indicated by arrow b, in the insertion station  100 . Concurrently, each deck strip of the transport deck  141  provides a continuous vacuum force upon the envelope  112  via vacuum plenums, so as to force the envelope  112  against the continuous running transport belts  121 ,  123 ,  125 . 
     Next, an elongate stopping portion  184  of the backstop member  180  is caused to extend above the transport deck  141  at a height sufficient to stop travel of the envelope  112  in the insertion station  100 . The leading edge of the envelope  112  then abuts against the stopping portion  184  of the backstop member  180 , so as to prevent further travel of the envelope  112 . 
     While the envelope  112  is abutting against the stopping portion  184  of the backstop member  180 , the transport belts  121 ,  123 ,  125  are continuously running beneath the envelope  112 . The continuous vacuum force applied to the envelope  112  by the deck strips acts to stabilize the envelope  112  on the transport deck  141  while it is abutting against backstop member  180 . The vacuum force, therefore, prevents undesirable motion of the envelope  112  caused by the friction of the continuously running transport belts  121 ,  123 ,  125 . 
     When the envelope  112  is disposed in the insertion station  100 , the vacuum cup  72  of the vacuum assembly  70  is caused to reciprocate downward towards the back panel of envelope  112 . The vacuum cup  72  adheres to the back panel and then reciprocates upwards, so as to separate the back panel from the envelope front panel to create an open channel in the envelope  112 . The enclosure collation  130  is then conveyed towards the envelope  112  by the pusher fingers  132 . 
     At first, the insertion horns  126 ,  128  are positioned in a first position in which their respective stripper blade portions  170  are positioned outside of the open end of the closed envelope  112 . Before the conveying enclosure collation  130  is advanced into the open channel of envelope  112 , each insertion horn  126 ,  128  is pivoted approximately 65 degrees towards its second position. When pivoted, the insertion horns  126 ,  128  provide a guide path into the open channel of the envelope  112  through which an enclosure collation  130  travels into the envelope  112 . 
     Referring also to  FIG. 3 , the invention may provide intersecting paper paths for a high speed inserter. In one embodiment, the invention comprises intersecting envelope paths and a controller to provide uninterrupted material flow of un-stuffed envelopes and stuffed envelopes through the intersection to a flap-down insertion location. The envelope hopper  200  may be located so as to be accessible to the operator and may provide a linear motion of the envelopes (i.e., no abrupt lateral or right-angle shifts in direction) down to the insertion deck. In some embodiments, the invention provides a flap-down inserter that includes many of the benefits of a flap-up inserter. 
       FIG. 3  illustrates the intersecting envelope paths and the surrounding geometry according to embodiments of the invention. The envelope hopper  200  contains a stack of envelopes  112  oriented face-up. The flaps of the envelopes are in a closed position in a flap-down and flap trailing orientation. Based on its location, as seen in  FIG. 1 , the envelope hopper  200  is accessible to the operator proximate to the open side  202 . The hopper  200  is located vertically above the transport deck  141 . The envelope path from the hopper  200  down to the deck  141  at the insertion station  100  provides a linear motion of the envelope (i.e., no abrupt right angle shifts in direction of the envelope from a first direction to an orthogonal second direction). In several conventional flap-down embodiments, the envelope hopper is located outboard (i.e., to the extreme right in  FIG. 3 ) of the Mailing Output System (MOS), making envelope loading difficult or impossible to accomplish from the operator side  202 . 
     Envelopes are fed by an envelope feeder from the hopper  200 . The envelope feeder comprises an envelope separating device  204  and an envelope staging nip  206 . Once an envelope is at rest and staged under the control of this nip  206 , at the appropriate time the staging nip  206  accelerates the envelope vertically downward and through the paper path intersection zone  208  to be received by the envelope staging areas  210 . 
     An envelope flap opening mechanism  212  is provided downstream of the intersection zone  208 . Also located within the envelope staging area  210  is an envelope diverter  214 , which is actuated to remove an envelope from the paper path in the event that that the envelope failed to open the flap at the envelope flap opener  212 . After an envelope exits the envelope staging area  210 , it enters the envelope insertion location  216  under the control of the vacuum deck  141  and comes to rest with its leading edge located at the rotary backstops  180 . 
       FIG. 4  illustrates diagrammatically the staging locations for leading edges (LE) of an envelope as it moves from the envelope hopper  200  to the insertion location  216  on the vacuum deck  141 , also sometimes referred to as the insertion deck. 
     As shown in  FIG. 4 , LE  1  is the position of the leading edge of the bottom-most envelope in the envelope hopper  200 . LE  2  is the position of the leading edge of the envelope at the envelope staging location proximate to the staging nip  206  upstream of the intersection zone  208 . LE  3  is the position of the leading edge of the envelope at the envelope staging location  210  downstream from the intersection zone  208 . LE  4  is the position of the leading edge of the envelope at the final envelope staging location (sometimes referred to as the arm position) before the envelope is delivered to the insertion deck  141 . LE  5  is the position of the leading edge of the envelope at the location of the envelope during insertion, where the leading edge of the envelope is defined by the location of the rotary backstops  180 . 
       FIG. 4  illustrates the five staging positions for a small depth envelope. Small depth envelopes are defined herein as envelopes having a depth of approximately 6.5 inches or less. Such envelopes typically accommodate tri-fold and half-fold applications. For small depth envelopes, the staging area  210  normally contains two envelopes. 
     Larger depth envelopes are defined as envelopes having a depth greater than approximately 6.5 inches. Those envelopes typically accommodate flats applications. For larger depth envelopes, the staging area  210  normally contains only one envelope, and the staging position shown in  FIG. 4  as LE  3  is eliminated. However, features of the invention may be used with envelopes having any suitable size. 
     The envelope staging nip  206  and the staging area  210  may be driven by a single servo motor or a plurality of motors (M 2 , M 3 , M 4 ), as shown in  FIG. 4 , to provide a rapid incremental start/stop motion to transfer envelopes from stage to stage within one insertion cycle. Once an envelope is stuffed on the vacuum deck  141 , its departure is controlled by the rotary motion of the backstops  180 , which pivot below the insertion deck, allowing the stuffed envelope to be pushed out of the insertion area by the overhead pushers  132  with the assistance of the constant velocity vacuum deck belts  121 ,  123 ,  125 . The stuffed envelope is subsequently held at nip  207  prior to passing through the intersection zone  208 . 
     The control system  14  (see  FIG. 1 ) ensures that all five envelopes move in unison, or perhaps slightly offset, in start/stop fashion and advance to the next staging area (i.e., LE location) within one cycle time. Once the stuffed envelope passes through the intersection zone  208 , it is conveyed by an output belt  218  for subsequent mail finishing in the MOS. 
     Control logic and envelope motion profiles are engineered and paper (e.g., envelope) path lengths are tuned and finalized to a single fixed geometry to allow un-stuffed envelopes to pass vertically through the intersection zone  208  when an inserted envelope (i.e., horizontal motion) is not present in the zone. Similarly, stuffed envelopes pass horizontally through the insertion zone  208  when an un-stuffed envelope (i.e., vertical motion) is not present in the zone. Therefore, during steady state operation, un-stuffed and stuffed envelopes pass through the intersection zone  208  alternately without colliding. In order to accomplish this, the combined time of both a stuffed envelope and an un-stuffed envelope (with the maximum allowable flap length) in the intersection zone  208  should not exceed one machine cycle. Velocities, motion profiles, and paper path lengths are determined accordingly to guarantee this across a wide range of envelope sizes. 
       FIG. 5  illustrates a rule that was created to ensure a highly reliable intersection zone  208 . The intersection zone  208  was established and timing was generated to ensure that no portion of two envelopes (stuffed and un-stuffed) are present in the intersection zone  208  simultaneously. In one embodiment, an intersection zone having a side dimension of approximately 2 inches was established to provide a large design margin in a motion control system, where maximum servo motion control errors typically do not exceed 1/16 of an inch. Intersection zones of other sizes may also be used. 
     The following table with the resulting cycle rates is an example for a wide range of envelope depths achieved without paper path velocities exceeding 125 inches/second or accelerations exceeding 8 g, where Tcycle is the period of a machine cycle in seconds. 
     
       
         
           
               
               
            
               
                   
                   
               
               
                   
                 Envelope Size 
               
            
           
           
               
               
               
               
               
            
               
                   
                 #10 
                 6.5″ × 9″ 
                 10″ × 13″ 
                 12″ × 9″ 
               
               
                   
                   
               
            
           
           
               
               
               
               
               
            
               
                 Envelope Depth 
                 4.125 
                 6.5 
                 10 
                 12 
               
               
                 (inches) 
               
               
                 Cycle Rate (K/hour) 
                 22 
                 18 
                 13 
                 11 
               
               
                 Max Flap (inches) 
                 2.56 
                 2.56 
                 2.56 
                 2.56 
               
               
                 Tcycle (seconds) 
                 0.164 
                 0.200 
                 0.277 
                 0.327 
               
               
                   
               
            
           
         
       
     
     Embodiments of the invention may provide a system having the advantages of flap-up devices, such as a simple paper path and accessible envelope hopper, as well as the advantages of flap-down devices, such as reliability of inserting. 
     Embodiments of the invention may provide an apparatus having an envelope transport system comprising a first feed path  230  configured to transport an envelope  112  from an input at an envelope supply  200  to an insertion location  216 , and a second feed path  232  configured to transport the envelope with an insert  130  therein from the insertion location  216  towards an output. The first and second feed paths intersect at the intersection zone  208 , which is spaced from the insertion location  216 . The paths  230 ,  232  are angled relative to each other at the intersection zone  208 . 
     The first feed path  230  is substantially vertical at the intersection zone  208  and the second feed path  232  is substantially horizontal at the intersection zone  208 . The first and second feed paths are angled relative to each other at the intersection at an angle of approximately 90 degrees. However, any suitable angle could be provided. The input from the envelope supply  200  is located vertically above the second feed path  232 . 
     In the embodiment shown, as best seen in  FIG. 3 , the second feed path  232  is substantially straight. The first feed path  230  comprises a downstream redirection of the envelope of approximately 180 degrees. The first feed path also comprises at least one redirection of about 90 degrees located upstream from that redirection. 
     The first and second feed paths may be configured to transport the envelope substantially simultaneously with a second envelope. The controller  14  is connected to drives M 1 -M 5  of the first and second feed paths. The controller, by controlling the drives M 1 -M 5  and the backstops  180 , is configured to allow only one envelope at a time in the intersection zone  208  proximate to the intersection. 
     Referring also to  FIG. 6 , the first feed path is configured to transport the envelope from the input to the insertion location  216  with a closed end  234  of the envelope, which is located opposite a flap end  236  of the envelope, as a forward leading edge of the envelope, and to deliver the envelope at the insertion location  216  in a flap-down position to insert the mail piece insert into the envelope. 
     Embodiments of the invention may provide an apparatus comprising an envelope supply, an insertion station configured to insert a mail piece insert into an envelope while the envelope is in a flap-down position, and a transportation system configured to transport the envelope from the envelope supply to the insertion location  216  with a closed end  234  of the envelope  112 , which is located opposite a flap end  236  of the envelope, as a forward leading edge of the envelope. 
     Referring also to  FIG. 7 , a method of the invention may comprise transporting an envelope along a first path from an input to an insertion location as indicated by block  240 , and transporting the envelope with a mail piece insert therein along a second path from the insertion location to an output, as indicated by block  242 . As indicated by block  244 , the first and second paths intersect at an intersection that is spaced from the insertion location. 
     Referring also to  FIG. 1 , the invention may comprise a controller  14  having a memory  26  with software forming a program storage device tangibly embodying a program of instructions executable by a machine for performing operations as described above. For example, the operations may comprise transporting an envelope along a first path from an input to an insertion location, and transporting the envelope with a mail piece insert therein along a second path from the insertion location to an output, wherein the first and second paths intersect at an angle at a location spaced from the insertion location. 
     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.