Abstract:
There is provided an envelope sealing apparatus for sealing an envelope (E) having a main body (m) and a sealable flap (f) at one end of the main body foldable about a hinge (h) between the flap and main body, the flap being sealable to said main body under applied pressure when folded about said hinge into contact with the main body, the apparatus comprising: a feed path along which an envelope can be fed; driving means associated with said feed path for, at least in part, feeding an envelope along said feed path; flap securing means cooperative with said driving means to secure an open envelope flap in contact with the driving means; and flap sealing means cooperative with said driving means to seal the flap to the main body when the driving means drives the envelope in a flap sealing direction along the feed path, wherein said driving means is movable from a flap securing position to a flap sealing position, the driving means being operable, in use of the sealing apparatus: (i) to secure an open envelope flap (f) in contact therewith cooperatively with said flap securing means; (ii) to move from the flap securing position to the flap sealing position with the flap secured in contact therewith, so as to at least partially fold the flap (f) about the hinge (h); and (iii) thereafter to drive the envelope (E) in the flap sealing direction along the feed path, so as to seal the flap (f) to the main body (m) by applying pressure cooperatively with said flap sealing means. A mail piece creation device incorporating such an envelope sealer is further provided, along with corresponding methods.

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
       [0001]    This application claims the benefit of the filing date of Dec. 21, 2006, for United Kingdom application number 0625656.4 which is owned by the assignee of the present application. 
       FIELD OF THE INVENTION 
       [0002]    The present invention relates to an envelope sealing apparatus and to a method of sealing an envelope. The invention finds specific application within a mail piece creation device, and to a method of creating a mail piece. 
       BACKGROUND 
       [0003]    It has been known to provide devices for automatically creating a finished mail piece. Such devices range from industrial scale units capable of producing a large throughput (high output) of mail pieces for distribution to a wide audience down to so-called SOHO (Small Office Home Office) mail creation devices having much smaller output capacity. 
         [0004]    The functionality of mail piece creation devices typically increases as the size of the device increases. Industrial scale mail piece creation devices represent a production facility in their own right. These facilities are configured to print large numbers of mail items for delivery to individual addressees. Each mail item is printed, collated, accumulated as necessary with other mail items, folded and inserted into an individual envelope. The envelope may bear an address window for displaying an address printed on the mail item, or may be separately addressed, in which case the envelope must be properly addressed to the intended recipient of the enclosed mail items. Once the mail item is inserted into its envelope, the envelope is automatically sealed and processed for delivery. Known devices of this kind are capable of producing individual mail items properly addressed for delivery to large target audiences, perhaps in mail shots of tens or hundreds of thousands of mail pieces, for example as would be required by large service organizations such as banks, utilities companies and governments. 
         [0005]    On a more modest scale, SOHO mail piece creation devices have been proposed for home and office use. Such devices are often also referred to as “desktop” mail piece creation devices, although they may, in fact, be floor-standing. Whereas industrial scale mail piece creation devices typically require a dedicated team of highly trained operators in order to maintain and run the production process, SOHO mail piece creation devices are intended to be facile to use and maintain, for operation by non-dedicated staff with a minimum of training. These devices are typically of the scale to produce a few thousand mail pieces per day, and thus find greatest applicability to medium-sized companies reaching a more modest target audience. Whereas the largest mail piece creation devices can achieve the full functionality described above, and are able to process a range of sizes of envelopes and sheets of paper, as well as being able to insert additional items into the envelopes via special inlet feeds, most SOHO mail piece creation devices are typically of a reduced functionality. Usually, this will entail the mail items being pre-printed, and then loaded into appropriate inlet feed trays. Similarly, the devices may be restricted to one, or maybe two, acceptable standard sizes for the mail items and envelopes from which the mail pieces are to be created. Furthermore, SOHO mail piece creation devices are typically designed to deliver large numbers of an identical mail piece to many receivers, rather than for creating recipient-specific mail pieces. 
         [0006]    Despite having been labeled as SOHO devices, very few existing mail piece creation devices are particularly suited for home use, and it would be very uncommon to find such a device as a piece of household equipment. However, household-related written correspondence continues in vast quantities, despite the recent advances in electronic communication, and a market exists for mail piece creation devices that would be suitable for individual or home use. 
         [0007]    The limiting factor in reducing the size of mail piece creation devices for such suitability has been in the need to retain adequate functionality in the device. Within such mail piece creation devices, each particular function in the above-noted process is carried out by separate mechanical system, requiring a corresponding proportion of space within such a machine for each paper handling or envelope handling process that is to be carried out. One such mechanism is the sealer apparatus that is used to close and seal the flap of an envelope, once the contents of the envelope have been inserted. 
         [0008]    A typical known envelope sealer receives an envelope along a path, with the open flap of the envelope at the trailing end with respect to the envelope feeding direction. The envelope is typically fed around a curved path portion into a straight insertion section, so that the main body of the envelope is held in an aligned configuration at the insertion location. As the envelope is fed so that its main body rests within the insertion chamber, it is halted at a position where the open flap remains partially within the curved path preceding the straight insertion chamber, to thereby hold the envelope in an open configuration, with the mouth of the envelope held open. Mail items can then be inserted into the envelope, into the open mouth. To assist in the insertion operation, insertion fingers may be inserted into the mouth of the envelope, to assist in guiding a mail item there into, while the flap is usually held securely in the open configuration, typically by a roller pair located in the curved path. 
         [0009]    Once the mail item has been inserted into the envelope, the envelope must typically be fed further along the feed path, to bring the hinge between the envelope flap and the main body into line with a sealing roller pair. The envelope is then fed hinge-first through the nip of the sealing roller pair, to close the flap to the main body, thereby sealing the envelope. Where a traditional gum-sealed envelope is to be used, a moistener is provided during this operation, to moisten the gum so that the envelope flap will seal. 
         [0010]    Due to the requirement for further transporting the envelope to bring the hinge into alignment with feed rollers, and in order to feed the envelope hinge-first into the roller nip, such a system is unsuitable for sealing envelopes containing very thick or non-flexible mail items, due to the need for the mail item to pass around a curved path so as to enter the roller nip hinge-first. Moreover, the various transporting, flap holding and flap sealing operations, including, where applicable, a flap moistening operation, require a complex series of mechanical feed devices for transporting and feeding the envelope and contents, resulting in fairly large and complex mechanical arrangements. 
       SUMMARY OF THE INVENTION 
       [0011]    According to a first aspect of the present invention, there is provided an envelope sealing apparatus for sealing an envelope having a main body and a sealable flap at one end of the main body foldable about a hinge between the flap and main body, the flap being sealable to said main body under applied pressure when folded about said hinge into contact with the main body, the apparatus comprising: a feed path along which an envelope can be fed; driving means associated with said feed path for, at least in part, feeding an envelope along said feed path; flap securing means cooperative with said driving means to secure an open envelope flap in contact with the driving means; and flap sealing means cooperative with said driving means to seal the flap to the main body when the driving means drives the envelope in a flap sealing direction along the feed path, wherein said driving means is movable from a flap securing position to a flap sealing position, the driving means being operable, in use of the sealing apparatus: (i) to secure an open envelope flap in contact therewith cooperatively with said flap securing means; (ii) to move from the flap securing position to the flap sealing position with the flap secured in contact therewith, so as to at least partially fold the flap about the hinge; and (iii) thereafter to drive the envelope in the flap sealing direction along the feed path, so as to seal the flap to the main body by applying pressure cooperatively with said flap sealing means. 
         [0012]    In preferred embodiments said driving means is movable from a flap securing position on one side of the feed path to a flap sealing position on the other side of the feed path. 
         [0013]    In further preferred embodiments, said driving means and said flap securing means may be mounted on a common securing support structure, so that as the driving means moves from the flap securing position to the flap sealing position, the flap securing means is supported to effect a complementary motion to ensure that an envelope flap thereby secured is maintained in contact with the driving means through at least a substantial portion of the motion. Similarly, said driving means and said flap sealing means may be mounted on a common sealing support structure, so that as the driving means moves from the flap securing position to the flap sealing position, the flap sealing means is supported to effect a complementary motion to ensure that, at the flap sealing position, an envelope driven in the flap sealing direction along the feed path by the driving means is subjected to an applied pressure. 
         [0014]    Embodiments of such an envelope sealing apparatus may further comprise a moistener adjacent to the flap sealing position, the moistener being configured and arranged to be capable of applying moisture to a portion of the flap prior to or during the envelope being driven in the flap sealing direction along the feed path. 
         [0015]    Typical embodiments of such an envelope sealing apparatus may comprise an envelope entry path, separate from the envelope feed path, along which envelopes are received into the sealing apparatus, wherein, with the driving means at the flap securing position, the driving means and flap securing means are configured cooperatively to secure the flap at a location along the envelope entry path. 
         [0016]    Further embodiments of the sealing apparatus may usefully comprise a flapper mechanism configured to unfold about the hinge the closed unsealed flap of an envelope received into the sealing apparatus with a closed unsealed flap, thereby to ensure that the envelope flap is open to be secured cooperatively by the flap securing means and the driving means at the flap securing position. In most useful arrangements the flapper mechanism will be located along an envelope entry path, to unfold the closed unsealed envelope flap at a location upstream of the location along the entry path where the driving means and flap securing means are configured cooperatively to secure the flap as the envelope is received into the apparatus. 
         [0017]    Even further preferred embodiments comprise an insertion location, wherein the main body of an envelope extends at least partially into the insertion location when the open flap of the envelope is cooperatively secured by the flap securing means and the driving means at the flap securing position and the envelope is thereby held open for items to be inserted into the main body of the envelope. In such embodiments, the envelope sealing apparatus may preferably further comprise an insertion frame including one or more insertion fingers arranged for insertion into the opening of an envelope held open at the insertion location, thereby to contribute to holding the envelope open for the entry of items into the envelope main body. Moreover, in embodiments including an envelope entry path as described above, then, at the flap securing position, the driving means is preferably arranged to engage an envelope received along the entry path and to drive the envelope along the entry path so that the main body extends at least partially into the insertion location. 
         [0018]    In yet further preferred embodiments said driving means comprises a driven roller movable from the flap securing position to the flap sealing position. In one preferred configuration the flap securing means includes a securing idler roller in cooperative engagement with the driven roller, the securing idler roller being mounted on a common securing support structure as described above; and said securing support structure is configured so that as the driven roller moves from the flap securing position to the flap sealing position the securing support structure rotates about an axis collinear with the driven roller axis to cause the securing idler roller to roll around at least a portion of the outer circumference of the driven roller, thereby to maintain a flap securely in contact with the driven roller as the driven roller moves. Similarly, said flap sealing means may include a sealing idler roller in cooperative engagement with the driven roller and defining a sealing nip between the driven roller and the sealing idler roller, the sealing idler roller being mounted on a common securing support structure as described above, with said sealing support structure configured so that as the driving means moves from the flap securing position to the flap sealing position, with a flap secured in contact with the driving means by said flap securing means, the sealing nip is brought into alignment with the feed path and substantially into engagement with the at least partially folded hinge. 
         [0019]    In still further preferred embodiments, the apparatus comprises a trapdoor forming at least a portion of the feed path, the trapdoor being mounted in proximity to the driving means and being displaceable from an envelope guiding position to a retracted position, thereby to allow the driving means to move from the flap securing position to the flap sealing position. In such embodiments, the trapdoor may be mounted on a trapdoor support frame, the trapdoor support frame being attached at least at one end to a support frame of the driving means, thereby to cause displacement of said trap from the envelope guiding position to the retracted position as the driving means moves from the flap securing position to the flap sealing position. 
         [0020]    The present invention further provides a mail piece creation device: for automatically inserting mail items into an envelope and automatically sealing the envelope, comprising: an envelope sealing apparatus according to any combination of the preferred embodiments set out above. 
         [0021]    According to a second aspect of the present invention, there is provided a method of sealing an envelope having a main body and a sealable flap at one end of the main body foldable about a hinge between the flap and main body, the flap being sealable to said main body under applied pressure when folded about said hinge into contact with the main body, the method comprising the steps of: providing an envelope to a flap securing location with the flap open; securing the flap in contact with driving means at the flap securing location, at least partially folding the flap about the hinge by moving the driving means with the flap secured in contact therewith to a flap sealing position, and driving the envelope with the driving means in a flap sealing direction along a feed path, and applying pressure cooperatively with flap sealing means as the envelope is driven, so as thereby to seal the flap to said main body. 
         [0022]    In the above method, the step of providing an envelope to a flap securing location with the flap open preferably includes opening the flap of a closed unsealed envelope before providing the envelope to the flap securing location. Furthermore, the step of providing an envelope to a flap securing location with the flap open preferably includes providing the envelope along an entry path with the main body trailing the flap. 
         [0023]    In a preferred embodiment of the method, the step of providing an envelope to a flap securing location with the flap open includes providing the flap to the flap securing location so that the main body extends into an insertion location; and the step of securing the flap in contact with driving means at the flap securing location includes holding the envelope open so that items may be inserted into the envelope main body. 
         [0024]    In a further preferred embodiment of the method, the step of at least partially folding the flap about the hinge by moving the driving means with the flap secured in contact therewith to a flap sealing position includes moving the driving means from one side of the feed path to the other side of the feed path. 
         [0025]    In yet further preferred embodiments of the method, the step of at least partially folding the flap about the hinge by moving the driving means with the flap secured in contact therewith to a flap sealing position includes moving the securing means relative to the driving means in order to maintain the flap secured in contact with driving means at least substantially entirely to the flap sealing position. 
         [0026]    In more preferred embodiments of the method, the step of securing the flap in contact with driving means at the flap securing location further includes inserting envelope opening means at least partially into the main body in order to hold the envelope open for the insertion of items into the main body. 
         [0027]    In even more preferred embodiments of the method, the step of at least partially folding the flap about the hinge by moving the driving means with the flap secured in contact therewith to a flap sealing position includes moving the flap sealing means so as to align the flap sealing means with the feed path. Preferably, the step of at least partially folding the flap about the hinge by moving the driving means with the flap secured in contact therewith to a flap sealing position includes substantially engaging the hinge with the flap sealing means. 
         [0028]    Even further preferred embodiments of the method further comprise the step of moistening at least a portion of the flap, before or during the step of driving the envelope with the driving means in a flap sealing direction along a feed path, and applying pressure cooperatively with flap sealing means as the envelope is driven, so as thereby to seal the flap to said main body. 
         [0029]    In yet more preferred embodiments, the step of driving the envelope with the driving means in a flap sealing direction along a feed path, and applying pressure cooperatively with flap sealing means as the envelope is driven, so as thereby to seal the flap to said main body, includes driving the envelope through a sealing nip of a sealing roller pair. 
         [0030]    In particularly preferred embodiments, the method is carried out automatically by an envelope sealing apparatus capable of applying the method to one or a plurality of envelopes sequentially. 
         [0031]    In still further preferred embodiments, the step of at least partially folding the flap about the hinge by moving the driving means with the flap secured in contact therewith to a flap sealing position further includes displacing at least a portion of a guide forming part of the feed path, thereby to allow the driving means to move to the flap sealing position. 
         [0032]    The present invention further provides a method including any combination of the methods set out above, and further comprising the step of inserting at least one mail item into the open envelope before the step of at least partially folding the flap about the hinge by moving the driving means with the flap secured in contact therewith to a flap sealing position. 
         [0033]    Embodiments of the present invention advantageously can provide a sealing apparatus that is useful for sealing envelopes containing thick or non-flexible mail items therein. Embodiments of the invention may also advantageously provide a sealing apparatus having a reduced size and being of relatively simple mechanical complexity, thereby facilitating incorporation of such an apparatus into a mail piece creation device. 
         [0034]    The mail piece creation devices provided according to the invention can be of reduced size and complexity, as well as being capable of creating mail pieces that include thicker or non-flexible mail items. 
         [0035]    Embodiments of the methods of the invention can achieve the aforementioned advantages when applied to a suitable sealing apparatus or mail piece creation device. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0036]    To enable a better understanding of the present invention, and to show how the same may be carried into effect, reference will now be made, by way of example only, to the accompanying drawings, in which: 
           [0037]      FIG. 1  is an external perspective view of a mail piece creation device loaded with paper and envelopes; 
           [0038]      FIG. 2  is an external perspective view of the mail piece creation device of  FIG. 1  in its unloaded state; 
           [0039]      FIG. 3  shows an internal cross-sectional view, schematically depicting the main internal components of the mail piece creation device of  FIGS. 1 and 2 ; 
           [0040]      FIG. 4  is an internal cross-sectional view of the mail piece creation device of  FIG. 1 , as an envelope is fed into the device; 
           [0041]      FIG. 5  is an internal cross-sectional view of the mail piece creation device of  FIG. 1 , showing the flap of an envelope being opened as the envelope is fed into the device; 
           [0042]      FIG. 6  is a close-up view showing the flap opening operation of  FIG. 5  in more detail; 
           [0043]      FIG. 7  is an internal cross-sectional view of the mail piece creation device of  FIG. 1 , showing the envelope at a flap securing position; 
           [0044]      FIG. 8  is an internal cross-sectional view showing the envelope at the flap securing position, and showing further details of the associated flap sealing apparatus; 
           [0045]      FIG. 9  is an internal cross-sectional view of the flap sealing apparatus of the mail piece creation device of  FIG. 1 , showing the envelope at the insertion position; 
           [0046]      FIG. 10  is an internal cross-sectional view of the sealing apparatus of the mail piece creation device of  FIG. 1 , showing the envelope at the envelope sealing position, immediately prior to sealing the envelope flap; and 
           [0047]      FIG. 11  is an internal perspective view showing the main components of the flap sealing apparatus and an associated drive mechanism. 
       
    
    
     DETAILED DESCRIPTION 
       [0048]      FIG. 1  shows a mail piece creation device  1 , loaded with a stack of sheets S held in a sheet feed tray  7  and a plurality of envelopes E held in an envelope feed tray  5 . The mail piece creation device  1  is a desktop mail piece creation device, of an equivalent or similar size to typically known desktop printers for personal or home use. The mail piece creation device  1  is generally contained within a housing  3 , from which project the sheet feed tray  7  and envelope feed tray  5 . At the front of the mail piece creation device  1 , there is provided a mail piece collection tray  9 , onto which completed mail pieces M can be received from mail piece ejection opening  13 . Power is supplied to the mail piece creation device  1  via a typical power supply cable  11 , configured to fit into the socket of a local electrical power supply. As shown in  FIG. 1 , the housing  3  is formed from an upper section  3   a  and a lower section  3   b , which can be opened about a hinge at the rear of the machine, to gain access to the internal paper handling feed paths of the mail piece creation device  1 , for clearing jammed envelopes and paper sheets. As is also suggested by the illustration in  FIG. 1 , the mail piece collection tray  9  is pivotally mounted to the lower housing section  3   b  to fit within a complementary recess in the housing  3 , for storing and packaging the device in a compact configuration. 
         [0049]    Referring to  FIG. 2 , the mail piece creation device  1  of  FIG. 1  is shown, absent the loaded sheets S and envelopes E, and finished mail piece M. As can be seen, sheet feed tray  7  feeds sheets into the mail piece creation device  1  through sheet insertion opening  15 , while envelopes held in the envelope feed tray  5  are fed into the mail piece creation device  1  through envelope insertion opening  17 . As well as mail piece collection tray  9  being retractable, as noted above, sheet feed tray  7  is also telescopically retractable from the position shown in  FIG. 2 , to reduce the external configuration of the mail piece creation device  1 . Both sheet feed tray  7  and envelope feed tray  5  may also be pivotally mounted to the upper housing section  3   a , for rotation between a retracted low-profile position and the unretracted operational position of  FIG. 2 . Furthermore, the sheet feed tray  7  and envelope feed tray  5  may be removable, if required for storage or transport. 
         [0050]      FIG. 3  shows the main internal components of the mail piece creation device  1 , in schematic form, in cross-sectional view. 
         [0051]    As shown, the mail piece creation device includes a sheet feed tray  7  which delivers sheets held in a stack on the sheet feed tray to a sheet inlet separator  74 . The sheet inlet separator comprises a roller and separator block, as commonly known, for feeding sheets individually one-at-a-time into the sheet insertion opening  15 . Sheets fed into the sheet insertion opening  15  are fed into a sheet inlet feed path  70 , where they are detected by sheet inlet sensors  72 . Sheets are driven along the sheet inlet feed path  70  by a pair of feed rollers  71 . Sheets fed along the sheet inlet feed path  70  pass into a sheet folding location, where they are received by sheet folder feed roller pair  76 . The sheets are then fed into the sheet folder formed by sheet folder rollers  78   a ,  78   b ,  78   c  and  78   d . As a sheet is fed between the first pair of rollers  78   a  and  78   b , the sheet leading end is halted (for example in a buckle chute), causing the sheet to buckle. The buckle is fed between the second roller pair  78   b  and  78   c , thereby creating a fold as the buckle passes through the nip between rollers  78   b  and  78   c . The sheet thus folded is typically formed with the fold one third of the length along the sheet. As the sheet is then fed through the second roller pair  78   b  and  78   c , it is again halted at the leading end (now formed by the fold), causing the sheet to buckle at a different location. The second buckle is now fed between the third roller pair  78   b  and  78   d , to cause a second, further fold in the sheet, typically two thirds of the length down the sheet. In the depicted arrangement of rollers  78   a ,  78   b ,  78   c  and  78   d , a so-called C-fold is produced, as known in the art, although the rollers may be operated to form a so-called Z-fold, if preferred. For simplicity, since such buckle folders are known in the art (see, for example, EP1 634 840 A1, which discloses a similar sheet folding arrangement), further description of the sheet folding apparatus is omitted. Other sheet folding mechanisms are known in the art, and may be used as appropriate to the particular application. 
         [0052]    Turning now to the envelope handling portion of the mail piece creation device  1 , envelopes are held in a stack on the envelope feed tray  5 . A feeder/separator  18  similar to the sheet inlet separator  74  is provided to feed envelopes one-at-a-time into the envelope insertion opening  17 . The envelopes fed into the envelope insertion opening  17  are received by a roller pair  20 , and detected by envelope inlet sensor  22 . The envelope inlet feed roller pair feeds the envelope, with the sealed end first, along envelope inlet feed path  26  formed by envelope inlet feed path guide plates  26   a  and  26   b . Just beyond the envelope inlet feed roller pair  20  is located a flapper  24  for opening the flap of an envelope that is fed into the mail piece creation device with the flap closed. Flapper  24  is actuated by a flapper link mechanism  24   a.    
         [0053]    Further along the envelope inlet feed path  26  there is a flap securing location at which a drive roller  32  and a securing roller  34  form a flap securing nip  35 . Beyond the flap securing location there is a trap door  28 , which forms a shaped guide panel of the feed path, to direct the envelope into an insertion location  30 , where the main body of the envelope can be retained in a straight configuration. Insertion feed roller pair  38  is provided to assist with receiving and feeding an envelope into and out from the insertion location  30 . A common securing support frame  40  links drive roller  32  and securing roller  34 , to thereby maintain these rollers in engagement, to form the securing nip  35  there between. The securing support frame  40  is rotatable about a pivot  40   a . The drive roller  32  is also mounted on a sealing support frame  42 , to which a sealing roller  36  is commonly mounted, preferably biased into engagement with the drive roller  32 . 
         [0054]    Beneath the trap door  28 , there is provided an insertion frame  50 , mounted to be rotatable around a pivot  51 . The insertion frame  50  includes insertion fingers  52  that are spring-mounted to be rotatable on the insertion frame  50  about a further pivot point  55 . The insertion frame is mounted so that as it rotates around pivot  51 , insertion fingers  52  extend to displace trap door  28  (also about a pivot), forcing the insertion fingers into the insertion location  30 , whereby they can extend into the open mouth of an envelope held in the insertion location. An insertion drive roller  53  is provided to assist in feeding items into the mouth of the envelope with the insertion fingers inserted therein. Furthermore, insertion frame  50  includes insertion guide  54  that can direct folded sheets from the sheet folding location along a path between the insertion fingers  52  and trap door  28 , to be driven into an envelope held in the insertion location  30  by a driving force from the drive roller  53 . By mounting drive roller  53  and insertion fingers  52  to be rotatable about a common axis, or closely spaced axes, items to be inserted into the envelope may be assuredly driven fully into the envelope from a position immediately adjacent to the open mouth of the envelope. 
         [0055]    Below the insertion location, there is provided a moistener wick  60 , held within a container  62  of moistening agent  62   a . The moistener wick is located so that, during a sealing operation, it will moisten the gum portion of an envelope flap, to thereby seal the envelope when the flap is closed against the envelope main body. 
         [0056]    Formed mail pieces are fed out of the mail piece creation device  1  by feeding them along feed path  46 , for ejection out of the mail piece ejection opening  13 , under the influence of mail piece ejection roller pair  13   a.    
         [0057]    More detailed description of the operation of mail piece creation device  1  will now be given with reference to  FIGS. 4-10 . 
         [0058]    As shown in  FIG. 4 , an envelope E has a main body m and a flap f joined to one another along a hinge h. The envelope is loaded on the envelope feed tray  5  either singly or in a stack, with the flap end at the trailing edge. As shown in  FIG. 4 , the envelope is fed by separator roller  18  into the mail piece creation device  1 , into the envelope insertion opening  17 , with the flap in the closed position (i.e., folded at hinge h). The single envelope E is fed into the envelope insertion opening  17 , where it is detected by inlet sensor  22 , and received by inlet feed roller pair  20 , at the inlet to envelope inlet feed path  26 . 
         [0059]    As shown in  FIG. 5 , an envelope so received is fed along the envelope inlet feed path  26 , between the fixed feed path guide plates  26   a  and  26   b , so as to follow a curved path that brings the envelope through the flap securing location by causing the envelope to be fed between nip  35  formed between drive roller  32  and securing roller  34  at a point along the envelope inlet feed path  26 . As shown in  FIG. 5 , as the envelope leading end proceeds along the envelope inlet feed path  26 , it engages kicker link  25  of the flapper link mechanism  24   a . With reference also to  FIG. 6 , it can be seen that as the envelope forces the toe of kicker link  25  out of the envelope inlet feed path  26 , the rotation of kicker link  25  causes the flapper link mechanism  24   a  to be actuated, bringing the flapper  24  into the envelope inlet feed path  26 . The flapper link mechanism  24   a  and the flapper  24  are so configured that, for envelopes above a certain size, the flapper  24  will be in the envelope inlet feed path  26  as the envelope flap f approaches the flapper  24 . As shown in detail in  FIG. 6 , the flapper  24  becomes forced between the envelope main body m and the envelope flap f. As the envelope E is further fed around the envelope inlet feed path  26 , through nip  35 , driven by drive roller  32 , the leading end of the envelope is directed by trap door  28  into the insertion location  30 . At the same time, the envelope flap f is forced by flapper  24  upwardly out of the envelope inlet feed path  26 , thereby obtaining an open configuration. 
         [0060]    Turning now to  FIG. 7 , there is illustrated the situation when envelope E has been fed further around the envelope inlet feed path  26 , so that the main body m of the envelope E is substantially entirely located within the insertion location  30 . The envelope may be driven into such a location by the drive roller  32 , with assistance from insertion feed rollers  38  in the insertion location. Feeding of the envelope E is halted as the envelope hinge h approaches the hinge threshold T (see  FIG. 8 ). In this location, the envelope flap f is retained in the nip  35  between drive roller  32  and securing roller  34 . Due to rollers  32  and  34  being cooperatively mounted on a common securing support frame  40 , the envelope flap f becomes securely held in the nip  35 . This may be achieved, for example, by forming the rollers  32  and  34  with an appropriately small clearance, or by biasing the securing roller  34  towards drive roller  32 . Referring to  FIG. 8 , the position of the envelope E shown in  FIG. 7  is depicted in more detail. 
         [0061]    As shown in  FIG. 8 , there is a hinge threshold T to or beyond which the hinge h must travel so as to ensure that the mouth of the envelope is properly received into the insertion location  30 , to enable mail items to be inserted into the envelope. 
         [0062]      FIG. 8  additionally illustrates an example of how the trap door  28  can be mounted onto a trap door frame  29 , to thereby form a guide path for the envelope, in the position shown in  FIG. 8 , so as to direct the envelope from the envelope inlet feed path  26  into the insertion location  30 . Trap door  28  is rotatably mounted onto the trap door support frame  29 , biased in a clockwise direction as shown in  FIG. 8 . One end of the trap door support frame  29  is pivotally mounted to the securing support frame  40  to which drive roller  32  and securing roller  34  are commonly mounted. The other end of the trap door support frame  29  is mounted on a follower  29   b , constrained to follow trap door frame guide path  29   a.    
         [0063]    In the embodiment shown, the flap f of the envelope E is held securely in the position shown in  FIG. 8  by locking the drive roller  32  against rotation. This allows a mail item to be inserted into the envelope at the mouth, during an insertion operation. 
         [0064]    An insertion operation takes place with the apparatus in the configuration depicted in  FIG. 9 . Specifically, with the flap f held between drive roller  32  and securing roller  34 , insertion frame  50  is rotated around pivot  51  so that the insertion fingers  52  extend into the mouth of the envelope E near to the envelope hinge h. This is achieved by the insertion fingers  52  forcing the trap door  28  into the feed path, against the trap door biasing force, so as to bring the insertion fingers  52  and insertion drive roller  53  into proximity with, and into, the open mouth of envelope E held in the insertion location  30 . As shown, this rotation by the insertion frame  50  in the direction of arrow A about the pivot  51  brings the insertion guide  54  into alignment both with a sheet insertion path  80  and with an inlet opening formed between the trap door  28  and the insertion fingers  52 . In this manner, folded sheets can be fed between roller pair  78   b  and  78   d , along sheet insertion path  80 , to be guided by insertion guide  54  between trap door  28  and insertion fingers  52 , into the mouth of the envelope E. Insertion drive roller  53  is then able to fully drive the folded sheet into the envelope E, due to its proximity to the mouth of the envelope at the location of the hinge h. 
         [0065]    With reference to  FIG. 10 , the filled envelope can then be sealed. To achieve this, the insertion frame  50  is first rotated in the direction opposite to arrow A in  FIG. 9 , away from the insertion location  30 . The drive roller  32  is then moved from its position at the envelope flap securing location, where it was originally located, to an envelope sealing position. As shown in  FIG. 10 , the envelope sealing position is reached by moving the drive roller  32  substantially in the direction of arrow B. This takes the drive roller  32  from one side (the upper side, in  FIG. 9 ) to the other side (the lower side, in  FIG. 10 ) of the feed path  46 , which is a continuation of the insertion location  30 . As the drive roller  32  moves in the direction of arrow B, securing support frame  40  is caused to rotate about pivot  40   a , giving rise to a relative rotation between drive roller  32  and securing roller  34  in the direction of arrow C around the axis  44 . This causes the securing roller  34  to travel part way around the outer circumference of drive roller  32 , as the drive roller moves in the direction of arrow B. This enables the end of the flap f to be retained securely between the drive roller  32  and securing roller  34  in the nip  35 . To ensure that grip of the flap is not lost, an appropriate amount of rotation of the drive roller  32  may be allowed, in order to maintain the desired position of the flap f in the nip  35 . As shown in  FIG. 10 , the rotation and downward motion of the drive and securing roller pair  32  and  34  brings the nip  33  of the drive and sealing roller pair  32  and  36  into the feed path  46  at the insertion location  30 . Furthermore, the motion of the securing roller  34 , constrained by the common securing support frame  40 , assists in maintaining the hinge h at a desired location in the feed path  46 , to thereby force the hinge h into the roller nip  33  between the drive roller  32  and sealing roller  36 . As shown schematically in  FIG. 10 , the hinge h of the envelope E is thus positioned ready for sealing in the sealing nip  33 . 
         [0066]    As is further evident from  FIG. 10 , the motion of the drive and sealing roller pair  32  and  36  in the direction of arrow B is constrained both by the rotation of the securing support frame  40  about its pivot  40   a , and by a follower portion  43  of the sealing support frame  42  being located within guide path  42   a . Likewise, the follower  29   b  of the trap door support frame  29  is constrained to follow the trap door frame guide path  29   a , as the other end supported by the common securing frame  40  is moved in the direction of arrow B while the support frame  40  is rotated in the direction of arrow C. This effectively brings the trap door out of the way of the feed path  46 , during the transition. 
         [0067]    In the configuration shown in  FIG. 10 , a moistening wick  60  is positioned adjacent to the drive roller  32  in the sealing position of  FIG. 10 . Because the flap is securely held in the nip  35  between drive roller  32  and securing roller  34 , the flap f is also brought into proximity or contact with the moistening wick  60 . The moistening wick  60  is located in a container  62  of moistening agent  62   a , typically water. 
         [0068]    To seal the envelope, drive roller  32  is driven in the direction of arrow C, to force the hinge h through the sealing nip  33 . As shown, driving engagement is maintained by the sealing roller  36  being held in biased engagement with the drive roller  32  by biasing means  36   a . As is evident, as the hinge h is fed through the sealing nip  33 , the envelope E is driven along feed path  46 . As the drive of the envelope E progresses, the flap f released from its held position in nip  35 , due to rotation of drive roller  32 , whereby the natural resiliency of the flap f brings the flap into contact with the moistening wick  60 , to thereby moisten the gum on the envelope flap. As the flap f and main body m are fed through the sealing nip  33  by continued drive of the drive roller  32 , the flap f is brought into pressing engagement with the main body m of the envelope E. This securely seals the envelope flap f against the envelope main body m. To assist in driving the envelope through the sealing nip  33 , drive may be supplied from the insertion feed rollers  38 . The envelope E is then fully fed through the roller nip  33  between drive roller  32  and sealing roller  36 , along the feed path  46 , as a completed mail piece M. Referring once more to  FIG. 3 , the completed mail piece M is received by ejection roller pair  13   a  and ejected from the mail piece ejection opening  13  onto the mail piece collection tray  9 . 
         [0069]    As an alternative to relying on the natural resiliency of the envelope flap f in order to moisten gum on the underside of the flap, the flap may instead be brought into positive engagement with the moistening wick  60 . One method is to move the hinge threshold T, or to reduce the radius of drive roller  32 , so that as the drive and sealing roller pair  32  and  36  moves to the envelope sealing position, with flap f securely held in the nip  35 , a buckle forms in the flap f that brings it positively into contact with moistening wick  60 . A further alternative is to provide a portion  40   b  of the feed path leading into the insertion location  30 , mounted on the securing support frame  40  between the drive roller  32  and the position of the secured flap (see  FIGS. 10 and 11 ). This portion  40   b  can be configured to press the flap f into engagement with the moistening wick  60  as the securing support frame  40  rotates to the envelope sealing position. 
         [0070]    The envelope sealing apparatus, which includes the drive roller  32 , sealing roller  36  and securing roller  34 , mounted on common support frames  40  and  42 , can then be returned from the envelope sealing position of  FIG. 10  to the securing position of, for example,  FIG. 3 , ready to receive any further envelope. 
         [0071]    Referring now to  FIG. 11 , the main components of the flap sealing apparatus are shown in perspective view, from the bottom-front-left-side of the mail piece creation device. From this view, the arrangement of the various rollers  32 ,  34 ,  36  on support frames  40 ,  42  can be seen. 
         [0072]    In particular, it can be seen how sealing roller  36  is held in biasing engagement with drive roller  32  by biasing means  36   a  mounted in sealing support frame  42 . On the right-hand-side of  FIG. 11 , the trap door support frame  29  is shown, including follower  29   b  in guide path  29   a , for moving the trap door  28  out of the path of the flap sealing mechanism as it descends to the flap sealing position. The feed path portion  40   b  for pressing flap f into contact with moistening wick  60  (in selected embodiments) is also visible. 
         [0073]    On the left-hand side of  FIG. 11 , detail of the sealing support frame  42  and how it is mounted to follower  43  to follow guide path  42   a  is shown. Guide paths  29   a  and  42   a  may simply be tracks formed in side plates that define the side edges of the paper feed paths, for example. Also shown, schematically, is a motor drive arrangement  90  for supplying drive from a motor  92  to the drive roller  32 . Because gears  94 ,  95  are mounted coaxially with the pivot  40   a  of securing support frame  40  and axis  44  of drive roller  32 , drive can be supplied from motor  92  to drive roller  32  at both the flap securing and flap sealing positions of the sealing mechanism, without requiring a complex drive-engaging mechanism, such as electronic clutches and the like. 
         [0074]    It will further be apparent that the securing support frame  100  on the left-hand-side of  FIG. 11  is shaped as a link mechanism, cooperating with actuating link arm  102 , to move the sealing mechanism between the flap sealing position and flap securing position, differently from securing support frame  40  that is configured to (simultaneously) actuate the trap door  28  by moving trap door support frame  29 . Any suitable means may be utilized to actuate link arm  102 , although a preferred embodiment is cam-driven. 
         [0075]    It will be appreciated that the envelope sealing apparatus described herein will be applicable to envelope sealing operations not restricted to the particular arrangement in the mail piece creation device herein described. For example, while the illustrated embodiment utilizes an insertion frame  50  and trap door  28  for inserting mail items into the envelope, such a configuration is not essential, and mail items may be inserted into envelope E along a different path, such as along feed path  46 . 
         [0076]    It is further to be noted that because the sealing apparatus is mobile from a flap securing position to an envelope flap sealing position, the envelope with mail item inserted therein is fed along a straight feed path from insertion location  30 , through feed path  46  and out of mail piece ejection opening  13 . This enables such an envelope sealing apparatus to be of particular use for sealing envelopes that contain rigid or non-flexible mail items. Such mail items might typically include, for example, CDs or DVDs, thick booklets, cardboard, and many other non-flexible mail items that one might wish to deliver by post. 
         [0077]    Similarly, while the illustrated embodiment is suitable for inserting a single folded sheet into a single envelope, each fed from a respective stack, it will be appreciated that the mail piece creation device is not so limited. In particular, known mail piece creation devices include means for collating a plurality of sheets, folding these simultaneously, and inserting them into an open envelope. The envelope sealing apparatus disclosed herein would be suitable for inclusion within such a mail piece creation device. 
         [0078]    Furthermore, it should be noted that specific components have been described which are useful for handling the envelope E in the described operation. However, flapper  24  and flapper link mechanism  24   a  would not be required at all in a device configured to receive envelopes that are provided in the open configuration, while moistening wick  60  and moistening agent container  62  would not be required for envelopes where it is not necessary to moisten the gum on the envelope flap. Envelopes are known, for example, containing gum portions on both the envelope flap f and envelope main body m that react when brought into mutual engagement so as to form a seal. 
         [0079]    Additional modifications are also conceived, for the various components of the sealing apparatus. For example, the flap securing operation could be achieved using an appropriate electromechanical gripping apparatus, other than a securing roller  34 . Likewise, an equivalent sealing operation may be achieved by using alternative cooperating feeding members, such as driving feed belts, to seal the envelope. This might be appropriate, for example, where it is required to fit the sealing apparatus into a mail creation device that has space only for a particular size or shape of sealing apparatus within the housing, within which to accommodate the apparatus. 
         [0080]    It is, of course, also apparent that rather than proceeding to feed the sealed envelope along feed path  46 , the finished mail piece could be ejected out of an opening at the end of insertion location  30 , by reversing the feed motion of the drive roller  32  and feed roller pair  38 , or equivalent driving means, after the sealing operation. 
         [0081]    Although mail piece creation is described above firstly by reference to feeding and folding a sheet and secondly by reference to inserting such a sheet, as one example of a mail item, into an envelope, it will be apparent that the sheet handling and envelope handling steps set out above can be carried out simultaneously or in different sequences of operation, up until the point of inserting the sheet into the envelope prior to sealing. The sequences of such operation are thus open to preference. 
         [0082]    Accordingly, it is to be understood that the present invention is defined by the scope of the appended claims. The accompanying drawings are merely illustrative, by way of example, and not limiting of the scope of protection. 
         [0083]    By utilizing the sealing apparatus and associated method of the present invention, the size of a sealing apparatus and associated mail piece creation device can be reduced, by reducing the amount of motion that the envelope to be sealed must undertake. Furthermore, the sealing apparatus can be utilized for sealing mail pieces including mail items that are thick, non-flexible or rigid, where the mail item could not be fed around a curved path.