Patent Publication Number: US-6663100-B2

Title: System and method for supplying stacked material to a utilization device

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
     The present application claims benefit of U.S. Provisional Patent Application Ser. No. 60/234,155, which was filed on Sep. 21, 2000, by H. W. Crowley entitled MATERIAL SUPPLYING METHOD AND SYSTEM, and is hereby incorporated by reference. 
    
    
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     This invention relates to devices that feed envelopes and other sheet-like material from stacks. 
     2. Background Information 
     Current estimates place the number of envelopes used annually in the United States at over 100 billion. A significant percentage of these envelopes are used in connection with bulk mailings, and are accordingly filled, addressed and processed by a variety of automated machines. A lynchpin of all automated processes is the automatic envelope inserter. Automatic inserters are large, complex machines that are loaded with contents to be inserted (e.g., individual letter sheets and/or fillers) and envelopes in which these contents are to be inserted. Other machines such as binders, that bind inserts together (into a books, catalogs, newspapers or magazines), presses that apply logos and decoration, addressing machines, and a variety of other machines are also used selectively to process individual sheet-like materials in bulk mailing and other processes. These various devices can be termed generally “utilization devices” as they utilize sheet-like materials that are typically dispensed in stacks. 
     FIG. 1 shows a high-volume envelope inserter used by industry. The exemplary inserter  100  is a large, modular unit that combines various contents stored in hoppers (not shown) in the rear  102  of the machine and that directs the contents (arrows  104  and  106 ) onto a raceway  108  downstream (arrow  110 ) toward a stack of envelopes  112 . At each point along the raceway, additional insert sheets are added to the contents. These contents may be folded, or otherwise compacted, to fit within the selected envelope by mechanism within the inserter. Envelopes are drawn from the stack  112 , and directed downstream (arrow  114 ) to a inserting station  116  at which the closed-but-unsealed envelope flaps  118  are opened so that the final contents  120  (shown in phantom for clarity) can be inserted thereinto. The filled envelopes  112  are then transferred further downstream (arrow  124 ) to a stacking position or further-processing module (not shown). 
     Industrial inserters are available from a variety of well-known companies including Bell &amp; Howell and Pitney Bowes. One example is the Bell &amp; Howell Imperial™. With reference to the envelope stack  112 , the stacking location or “feed station”  130  consists of a series of upright guide rails  132 ,  134  that, respectively, contain the four opposing sides of each envelope in the stack. In most commercially available machines, the envelope stack, as well as the hoppers (not shown) for the insert contents, are open at the top and exposed for easy access. This is, in part, because inserters typically consume envelopes in the range of 3000-25000 pieces per hour. Conversely, the contents hopper and envelope feed station only have capacity for a stack of approximately 300-400 pieces. As such, the various stations of the inserted must be constantly monitored and reloaded by one or more individual operators. 
     With further reference to FIG. 2, the cycle of feed station loading is more-clearly illustrated. A stack of a few hundred blank or pre-printed envelopes  142  is removed from a box  140  of one thousand. The box may be accessed through a top that exposes the envelopes on-edge as shown, or through another opening. In any case, a grouping  150  is lifted manually from the box  140 , often bounced one or more times against a flat surface in an attempt to ensure registration, and then deposited (arrow  152 ) to the feed station  130  onto the stack  112 . The envelopes are then drawn out of the stack  112  one at a time using any one of a number of singulating feed techniques. In the exemplary feed station, friction feed rollers  156 ,  158  and  160  operate in conjunction with a non-rotating gate wheel  162  to singulate and feed envelopes downstream to the insertion location from the stack bottom. Pushers, vacuum belts and sliding tables are also used to singulate envelopes and/or contents according to alternate arrangements. 
     The above-described stack-loading technique, in which small discrete bundles are transferred from the box to the feed station, can give rise to may different (often recurring) failures. For example, repetitive loading of relatively small bundles of envelopes increases the possibility of a feed failure for a given envelope from the stack based upon the sudden application of significant force to the stack bottom as envelopes are dropped into the feed station. This is an ongoing concern as stacks are typically fed from their bottoms against the entire overlying weight/friction of the remaining stack. In addition, it is critical that envelopes be loaded in only one orientation every time. In other words, flaps must generally be placed face-up, and in a specific direction. Nevertheless, there are at least four different possible orientations in which rectangular envelopes can be loaded into the stack—of which three out of the four orientations are incorrect. Given the continuous and repetitive nature of the loading process, it is not uncommon for an operator to miss-load envelopes fairly regularly. Moreover, the stack orientation of envelopes required by the inserter may be geometrically reversed from that in which the envelopes are removed from the box. This means that the operator must often rotate, flip over, or otherwise reorient the envelopes each time they are loaded. Over a period of time, the repetitive lifting of a heavy stack of envelopes and constant reorienting of this time can fatigue the operator and cause progressive orthopedic injuries. In fact, the related motions involve slitting open a continuous progression of envelope boxes with sharp blades to remove the contents further exasterbates fatigue and possible injury. Finally, the simple monotony of constantly and repeatedly reloading of relatively small bundles of envelopes into an open hopper seems an unavoidable but equally undesirable byproduct of inserter operation. 
     Prior proposals for increasing the efficiency of envelope and contents stack-loading have included the feeding of envelopes or insert pieces from large bound rolls, such as described in U.S. Pat. No. 5,282,350 to Crowley. Alternatively, the feeding of envelopes from large, palletized balk cassettes has been suggested according to U.S. Pat. No. 5,478,185 to Krantz. However, while these techniques show promise, they require owners of inserting machines to make a large investment to retool the existing install base of machines, which may unacceptably increase production costs thereby straining fragile profit margins. In addition, these techniques may prevent the equipment from being easily returned to conventional bundle-feeding when needed (such as when a small custom job is desired). 
     Accordingly, it is an object of this invention to provide an system and method for providing a large stack of sheet-like materials, such as envelopes, to a utilization device that reduces the number of stack-loading cycles required by the operator and essentially eliminates direct operator contact with discrete bundles of the materials. This system and method should also reduce the amount of effort spent by an operator in preparing a material supply container (box of envelopes) for use, and should increase the stack capacity of existing utilization devices without requiring substantial refit or retooling or the devices&#39; feeding components. This system and method should also preferably allow material supply containers to be easily reused with minimal repair or refit. The containers should be collapsible into easily stored and transported shapes. 
     SUMMARY OF THE INVENTION 
     This invention overcomes the disadvantages of the prior art by providing a system and method for storing and dispensing stacks of sheet-like materials using a container that encloses a large number of stacked, sheet-like materials (such as envelopes) having a common predetermined orientation within the container. The container is arranged with a release mechanism at a dispensing end or opening thereof, arranged so that when the container is mounted in an appropriate sequence on a stacking location/feed station on a utilization device, the container releases its stack into the feed station for use by the utilization device. 
     In an illustrative embodiment, the feed station can include guides that, in conjunction with the container, enable the container to extend and further guide the stack beyond the top ends of the guides. In this manner, the overall capacity of the utilization device feed station is increased. The feed station is preferably adapted so that it can be readily used in a conventional manner by manual loading of smaller, discrete bundles materials and/or stacks of materials without use of the container if desired. 
     According to one embodiment, the dispensing end or opening includes a set of folds adapted to fold inwardly toward the inside walls of the container when the container is directed over the guides. This enables the stack to drop onto the feed station guides. The outer dimensions of the container can be sized to allow the container to fit over the guides so that it comes to rest at the bottom of the feed station. 
     According to another embodiment, the container can comprise a box-like structure having a variety of operator-actuated release mechanisms that normally restrain the stack from passage out of the dispensing end or opening, but based upon a predetermined movement (generally once the dispensing end or opening confronts the opening of the feed station), the dispensing end or opening releases the stack into the feed station. The container may be adapted to define an extended guide for a deeper stack, and appropriate internal structures can be provided to the container to facilitate support and guiding of a deeper stack. In one embodiment the dispensing end or opening of the container includes an interlocking flap closure structure with a series of overlapping tab sections that positively retain the stack against outward movement, but that can be opened by applying a force in an opposing inward direction to unlock the interlocking flaps from each other. 
     In another embodiment, the container can define any number of non-fully enclosing structures that restrain the breakup of the storage stack until the release mechanism is activated. For example, the container can be a ribbon or wrap that is broken and withdrawn once the stack is deposited in the feed station. The container can be a comb-like structure that supports an edge of the stack, and is withdrawn after deposition in the feed station. Similarly, the container can be a plurality of interconnections between adjacent materials in the stack, that are typically adhesively joined, and broken free at a desired time. The container can also comprise an extended feed surface that may be removable, for causing a waterfall of materials into the feed station from the larger feed surface. 
     In yet another illustrative embodiment, a container in the form of an envelope-filled cassette is provided. The cassette is arranged with a dispensing end or opening that can be opened by the user or an alternate closure along some or all of the elongated length thereof so that all, or a substantial portion, of the envelope contents can be randomly accessed for manual feeding or other uses. The dispensing end or opening, in one embodiment can be opened by removing the bottom using a tear strip, embedded below the surface of the cassette, that causes the bottom to separate from the remainder of the dispensing cassette by pulling the tear strip away from the circumference of the box. A fixture is located on the stacking location/feed station and defines a receptor for the cassette. The receptor is adapted to support the cassette so that it is suspended out of interfering contact with the workings of the feed station, bridges and maintains continuity between any material previously located at the feed station and the start of feed from the newly mounted cassette, and generally allows visual inspection of the flow of envelopes from the feed station so as to enable change of the cassette at the appropriate time and overall observation of the rate of consumption. To accomplish this interconnection between the receptor and cassette, the receptor includes three or four sides in which opposing sides force the cassette into a proper (squared) orientation. The receptor can include a slanted wall and a straight wall, opposite thereto, in which the slanted wall urges envelopes entering (dropping into) the feed station from the cassette against the straight wall for proper justification of the entering envelopes. The receptor can include, on two opposing walls, sets of flexible guide strips that deflect away from the cassette in the area in which it occupies, but that straighten in an area below the bottom edge of the cassette so as to firmly hold the cassette in place and justify the envelopes along adjacent edges as they leave the cassette bottom. The guides can be adjustable for length and width using a variety of moving and locking mechanisms (for example, slides, thumb screws, etc.). Finally, the cassette can be constructed with a shoulder seam or other key that interacts with a corresponding structure in the receptor in a manner that allows the cassette and receptor to mate only in a desired orientation. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The foregoing and other objects and advantages of the invention will become clearer with reference to the following detailed description as illustrated by the drawings in which: 
     FIG. 1, already described, is a somewhat schematic perspective view of a material utilization device in the form of an envelope inserter, according to the prior art; 
     FIG. 2, already described, is a schematic diagram of a conventional procedure for loading materials that comprise envelopes into the inserter of FIG. 1 according to the prior art; 
     FIG. 3 is a perspective view of an envelope loading system and corresponding feed station on a utilization device for receiving the envelope loading system according to an embodiment of this invention; 
     FIG. 4 is a perspective view of a container for storing and dispensing envelopes according to an embodiment of this invention; 
     FIG. 5 is a perspective view of the container of FIG. 4 shown in an opened configuration; 
     FIG. 6 is a schematic side view of a loading procedure for a container containing envelopes onto the feed station according to an embodiment of this invention; 
     FIG. 7 is a schematic side view of the completed loading procedure according to FIG. 6; 
     FIG. 8 is a schematic side view of a modified feed station for use with containers of this invention; 
     FIG. 9 is a schematic side view of a container in engagement with the modified feed station of FIG. 8; 
     FIG. 10 is a perspective view of a folded container end adapted to release envelopes into the feed station shown in a closed state; 
     FIG. 11 is a perspective view of a container end of FIG. 10 shown in an open state; 
     FIG. 12 is a perspective view of a container for dispensing envelopes according to an alternate embodiment; 
     FIG. 13 is a schematic side view of a container for dispensing envelopes according to another alternate embodiment of this invention; 
     FIGS. 14-17 are each schematic side views of containers for dispensing envelopes according to various alternate embodiments; 
     FIG. 18 is a schematic perspective view of a framework for storing and dispensing envelopes according to an embodiment of this invention; 
     FIG. 19 is a schematic side view of the framework of FIG. 18 to dispense envelopes to utilization device feed station; 
     FIG. 20 is a schematic side view of a wrap for enclosing and dispensing envelopes into the feed station according to an embodiment of this invention; 
     FIG. 21 is a schematic side view of a series of interconnections that contain and facilitate dispensing of the envelopes to the feed station according to an embodiment of this invention; 
     FIG. 22 is a schematic side view of an extended feed dispenser according to an embodiment of this invention; 
     FIG. 23 is a schematic representation of the removal of bulk envelopes for transfer to the extended feed dispenser of FIG. 22; 
     FIG. 24 is perspective view of a feed station receptor structure according to an illustrative embodiment of this invention; 
     FIG. 25 is a perspective view of a container defining an envelope cassette for use with the receptor of FIG. 24; 
     FIG. 26 is a perspective view of the receptor of FIG.  24  and cassette of FIG. 25 in engagement with each other; and 
     FIG. 27 is an exposed perspective view of an alternate embodiment of a container or cassette for dispensing envelopes or other sheet-like materials according to this invention; 
     FIG. 28 is a perspective view of another alternate embodiment of a container or cassette for dispensing envelopes or other sheet-like materials according to this invention; and 
     FIG. 29 is a perspective view of another alternate embodiment of a container or cassette for dispensing envelopes or other sheet-like materials according to this invention. 
    
    
     DETAILED DESCRIPTION OF ILLUSTRATIVE EMBODIMENTS 
     FIG. 3 shows a generalized system for feeding of envelopes or other sheet-like materials in stacks according to an embodiment of this invention. A utilization device feed station  200  is provided. This feed station for the purposes of this example, is the envelope feed location for a conventional high volume inserter as described above. It is adapted to hold a stack of envelopes approximately 300-400 pieces high. The exact size and shape of the envelopes or other sheet materials described for the purpose of this embodiment. They can be rectangular, square or even non-rectangular shapes. All items in a stack are approximately the same size and shape for ease of dispensing and storage. The feed station  200  includes a set of upright guides  202 ,  204   206  and  208 . The guide define narrow-width bars, typically formed from metal or another rigid material. In this example, side guides  202  and  204  are place along the exemplary narrow sides of the envelope while two sets of three guides  206 ,  208  along the opposing elongated sides of the envelopes. Spaces  210  are defined generally between the guides  206  and  208  and the corners are left open ( 212 ). The open nature of the guide allows the level and condition of the envelope stack to be easily viewed, jams to be cleared quickly and friction on the envelopes as they drop down the feed station, being withdrawn by the feeder mechanism, to be reduced. With reference to the feeder mechanism, any acceptable feed device for removing envelopes can be employed. The mechanism shown in FIG. 2 is one possible feed mechanism. However, it is expressly contemplated that feeding of envelopes from the bottom, or any point along the stack can be performed according to this invention. 
     Shown above the feed station  200  is an envelope storing and dispensing container  230  according to an embodiment of this invention. The container is sized with a width W and length L that is sufficient to enclose the perimeter of subject envelopes  232  stacked therein. The container includes a top section  234  that can be partially open/exposed (as shown—revealing a flap side of an exemplary envelope) or the top  234  can be fully covered. A groove  236  can be defined along the length of at least one side  238  of the container to show the level of envelopes within the container and their general condition. It is contemplated that all envelopes are placed in the same orientation (e.g., all flaps are located in the same direction along the side of the container). One or more indicia  240  can be provided on the container to assist an operator in understanding the orientation of the container contents. 
     As will now be described in detail, the container “dispensing end or opening”  242  is particularly adapted to enable envelopes to be easily transferred in bulk, from the container  230  into the feed station  200  without requiring individual subsets of envelopes to be handled or removed by an operator. In other words, this container and the others to be described herein enable direct transfer of envelopes and other sheet-materials in their entirety from the container into the stack feed location with little or no operator contact with the container content. In addition, where applicable, the container provides further guidance of envelopes or other sheet-materials while the container remains engaged with the feed station. 
     FIGS. 4 and 5 show an exemplary dispensing and storage container  350 , according to an embodiment of this invention, in more detail. The container in this embodiment can be formed from a durable plastic, card stock, corrugated cardboard or any other material appropriate for constructing containers designed to support the weight of 500-1000 envelopes or other sheet-like items during shipment and handling. The thickness of the container stock, as well as the kind of joints used to secure the container stock together (staples, adhesives, folds), are widely variable and depend in part upon the desired strength characteristics of the container. 
     The container  350  defines a width W and length L that are scaled generally to the perimeter size of the envelopes and a depth D that depends upon the total number of envelopes to be stacked within the container. The dispensing end or opening  352 , and opposing closed end  354  of the container  350  are shown alternately in a closed an opened configuration in FIGS. 4 and 5, respectively. The ends  352  and  354  are defined from a series of folds in the corresponding sides that generate an open center  356 . This closure structure retains the stored envelope stack against passage out of the container. In particular flaps or shoulders  358  and  360 , that result from folds along the fold lines  362  (FIG. 5) generate the desired closure. An optional retaining strip  366  (shown in phantom) can be applied over one or both of the container ends  352  and  354  to prevent the flaps/shoulders  358  and  360  from releasing inadvertently during transport or handling. This tape can be quickly removed prior to use. Other temporary end reinforcing techniques such as adhesive spots on folds, removable pull tabs or other techniques for strengthening the ends can be employed, an end can remain relatively free to open so long as it is left upright so that the weight of the envelope stack within the container does not bear upon it. In addition, more advanced folding techniques (described below) can be employed that resist outward opening (yet enable ready dispensing) at the dispensing end or opening. 
     Referring now to FIG. 6, use of the container in a feed station stack-loading process is described in detail. The container  350  contains a stored stack  370  of envelopes or other sheet-like materials to be dispensed. The dispensing end or opening  352  of the container  350  is brought over (or adjacent to) the feed station  200  so that sides of the container are aligned with the upright feed station end guides ( 202  and  204 ). The counter-posed sides of the container should, likewise, be aligned with the corresponding side guides  206  and  208  (not shown for clarity—refer to FIG.  3 ). 
     In this embodiment, the length L and width W of the container  350  should be at least slightly greater than length LF and width WF defined by the outer perimeter of the feed station guides  202 ,  204 ,  206  and  208 . In addition, the top edges  376  of the guides  202  and  204  should be shaped to assist in directing the inner surfaces of the container over the outer surface of the guides. A downward pressure (arrow  380 ) is applied to the container  352  onto the guides. The top edges  376  of the guides force the container flaps/shoulders  360  (and corresponding opposing flaps/shoulders  358 , not shown for clarity—refer to FIG. 4) to pivot upwardly (arrows  381 ) about their respective folds  382 . 
     The length LE of the envelopes in the stack is less than the average length L of the container. Likewise the length of the envelope stack is less than the width W of the container. In this manner, an open space SC is created between the envelope stack and the container walls. The open space SC, combined with the inherent compressibility of the envelopes, enables the container closure flaps/shoulders  360  (and counter-posed flaps/shoulders  358 ) to fold fully against the inner walls of the container sides. 
     As the forcible directing of the container down onto the guides  202  and  204  continues, the stored stack  370  is released onto the feed station  200  to join the preexisting stack  390  (if any) in the feed station. The open space SC provides clearance for the guides to nest when the container is passed fully thereover. Note that the shoulders  360  are folded up between the inner walls of the container and the outer surfaces of the guides. The top edges  376  of the guides should be shaped (typically with a funnel-like profile) so as to urge the stack into the guides free of any binding of envelopes at the top of the guides. 
     Since the overall depth D of the container is greater than the length of the guides, it enables the container to act as a supplemental guide unit, thereby enabling additional envelopes or other sheet-materials to be fed to the feed station  200 . While it is contemplated that sheet-to-sheet friction can generally maintain the stack in appropriate alignment, additional inner guides  392  (shown in phantom) can be deployed within the container. These guides can comprise perforated strips that are folded-in to fill the distance SC in the upper portion of the container or another acceptable structure. They can also comprise external guide bars that are placed through holes in the top of the container such as the exemplary bar  394  (shown in phantom). Such bars are removed prior to removal of the container  350 , once a certain level of the stack therein has been exhausted by the feeding process. 
     A variety of other deployable structures can be provided to the container so as to selectively project into the enclosure of the container to contact the envelopes. One such possible structure is a deployable shoulder that provides drag on envelopes at predetermined locations along the depth D. This can serve to prevent the extended feed stack within the container from bearing to heavily on the bottom of the stack until a predetermined number of envelopes below the deployable structure have been exhausted. Such shoulders operate by hanging-up a side of the envelope requiring it, and overlying envelopes to become angled sufficiently downwardly before they drop toward the bottom of the stack. The envelopes only become sufficiently angled when the opposing side is lowered sufficiently as a result of the feeding away of the lower portion of the stack-until it is safe top deposit additional weight onto the lower portion. 
     Additionally, spacers (not shown) can be provided to limit the final resting position of the dispensing end or opening of the container with respect to the feed station surface. In other words the distance that the container can move downward onto the guides can be limited. This serves to prevent the dispensing end or opening from interfering with passage of sheets out of the bottom of the stack or interference with any part of the feed station&#39;s singulating/advance mechanism. Spacers can be attached to the guides, placed at non-interfering locations on the feed station perimeter surface, or formed onto the dispensing ends/openings as pullout tabs, for example. 
     Note that a particular advantage of the above-described arrangement is that the feed station can be used in a conventional manner without the use of the container according to this invention. In other words, manual feed of batches of envelopes can still be accomplished when container-feeding is not desired or is not available. 
     FIG. 8 shows further modified guides  202  and  204  including hook members  400 . As shown further in FIG. 9, placement of the container  350  over the guides  202 ,  204  causes folding of the flaps/shoulders  360  as described above. The folded flaps/shoulders  360  are then captured by the undercut lower ends of the hooks  400  so that upward movement (withdrawal) of the container out of contact with the guides  202  and  204  is resisted. This can be used to provide a safety mechanism to prevent containers to be removed prematurely. Alternatively, where containers are sufficiently flexible the hooks  400  can be used to force the shoulders open as the container is removed. This is accomplished because the hooks cause the shoulders to pivot outwardly along their folds  382  as force is applied in an upward direction. 
     FIGS. 10 and 11 show an embodiment of a container dispensing end or opening  430  having a flap/fold structure that particularly resist outward opening, but that are capable of being forced inwardly to dispense its materials, in the manner described generally above, when the container end  430  is directed into contact with appropriately shaped guides. The end  430  consists of four discrete flap closure sections. Two side flaps  432  are joined to the corresponding side corners  434 . These flaps are angled downwardly to tabs  436 . A somewhat trapezoidal upper flap  440  is joined to the upper corner  442 . It is angled toward a centralized tab  444  that extends beyond the midpoint along the widthwise direction (double arrow  448 ). Note, “upper” is used only for the purposes of this illustration. An opposing, somewhat rectangular lower flap  450  is joined to the lower corner  452 . It defines a notch  454  between two end tabs  456  that each extend beyond the midpoint in the widthwise direction. The length of the notch in the lengthwise direction (double arrow  460 ) is slightly longer than the upper flap tab  144 . 
     The flaps  432 ,  440  and  450  form an interlocking closure (FIG. 10) in which and extended portion of each half (tabs  436 ,  444  and  456 ) underlie an inner-facing portion of an adjacent flap. This positively prevents outward opening of the closure. 
     Conversely, when upright guides  470  (shown in phantom) are directed (arrow  472 ) against the flaps, the fold inwardly about their respective corners as denoted by the curved arrows  480  with little resistance from the closure structure. The inner perimeter dimensions of the container, and the compressibility of the stack can enable guides to enter the container, and the flaps to fold up into a space between the edge of the stack and the inner container walls (as described generally above). 
     Note that, following a movement inwardly to collapse the interlocking flap structure, a subsequent outward/withdrawal movement may allow the flap members to become opened outwardly, thereby enabling the materials to be dropped from the container into the feed station without fully engaging the container onto the feed station. 
     The particular size and shape of the flaps and folds for the container end  430  can be varied based upon the characteristics desired. By reducing the area between interengaging members of the flaps, the flaps may be easier to open, but may also exhibit weaker materials-retention characteristics when closed (FIG.  10 ). The best shape for flaps can be determined by trial and error, feeding actual stacks into the feed station using containers differing flap dimensions, until a desired balance of strength to ease of opening is achieved. As used herein the term “interlocking flap closures” can be used to describe a flap and fold structure that includes overlapping, interlocking pieces that hold together in one direction to positively retain the materials in the container, but that can be unlocked by applying a release force in a second direction. 
     FIG. 12 shows a more basic release mechanism for a container  500  used for storing and dispensing a full stored stack of envelopes, or other sheet-like materials, to a feed station according to an embodiment of this invention. The container  500  can include a stack  502  of envelopes or other sheet-materials that is dispensed through its downwardly facing dispensing end or opening  504  after first removing an optional adhesively attached securing strip  506  or other retaining device and then allowing the envelope stack  502  to drop, shingle or waterfall into the feed station. This strip can be substituted for an alternative storage/shipping lid or cover. In another embodiment, the lid/cover can be omitted entirely, and the container can be simply stored with the open dispensing end or opening facing upwardly. A slot  510  can be provided for one or more fingers of an operator&#39;s hand  512  to holds the envelope stack in place as the container is turned over into a dispensing position—in which the stack drops by gravity into the guides of the feed station. The bottom is otherwise open and free of any obstructions to the flow of envelopes there through, requiring the finger to retain envelopes until final dispensing can be accomplished. The size of the container can be closely conformed to that of the envelope stacked perimeter, or it can be large enough to pass over the outer edges of the guides (in which case, the container can also act as a supplemental extension stack guide as described above). Note that the opposing closed end  508  of the container  500  is typically enclosed sufficiently to prevent escape of the envelope stack therefrom. This enables the container to be securely held in an inverted orientation, with the envelope stack supported against the closed end  508  under gravity, until final dispensing is accomplished by turning over the container to present the dispensing end or opening  504  to the feed station. 
     The basic embodiment of FIG. 12 clearly illustrates a salient concept of the invention. That is, that a container or other device for collecting an entire stack of envelopes or sheet-materials can be provided that enables bulk transfer of container&#39;s contents to an appropriate feed station without substantial operator intervention in the transfer of discrete subsets of the overall container contents. 
     FIG. 13 details an alternate embodiment of the invention in which the container  520  includes an active release mechanism. The internal stack  522  of the container is normally blocked by triangular shoulders  524  formed on at least two of the four container sides. These shoulders can be constructed by joining separate pieces together, or preferably, by folding and joining extensions of the container side walls. The shoulders act as a triangular truss support that normally serves to provide substantial resistance to passage of the stack  522  therethrough in a closed orientation. A clearance space CS 1  is defined between the edges of the stack  522  and the outer sides  530  of the container. This space is sufficient to enable passage of the sides  530  over the sides  202  and  204  of the feed station  200 . The container can be adapted to be passed fully over the guides, or can be used simply to transfer stack onto the feed station without acting as a supplemental guide. Where the container is adapted to be passed over the guide, the stops  524  can be segmented so that they are located only between the guides, and for example, the corner spaces (see FIG.  3 ). 
     In a dispensing operation, the container  520  is first presented to the feed station guides  202 ,  204 . Then, selected portions  536  of the container sides  530  can be depressed (arrows  534 ) inwardly as shown in phantom, into a clearance space CS 1  by inwardly pressing the selected portions  536 , a bending moment (curved arrows  538 ) is generated adjacent the supports  524 , thereby allowing the stack  522  to pass through the bottom of the container and into the feed station  200 . 
     FIG. 14 illustrates anther embodiment for a container  550  having a release mechanism in which triangular supports  552  enclose the dispensing end or opening of the container  550 . Tabs  554  extend outwardly from the container sides  556  when the container is located over the feed station  200 , the tabs  554  are moved outwardly (arrows  558 ), causing the tabs  552  to withdraw sufficiently for the stack  560  to pass into the feed station  200 . 
     FIG. 15 shows an embodiment of the container  570  in which the dispensing end or opening is enclosed by a tab or other flexible securing mechanism  572 . By removing the tab or other mechanism, the stack  574  passes into the feed station. The container can be passed over the guides  202  and  204  once the tab  572  is removed. Alternatively, the tab  572  can be segmented so that it passes between the guides  202 ,  204  allowing the container to be passed mostly onto the feed station before the tab assembly requires removal. 
     FIG. 16 shows another embodiment for a container  580  in which the dispensing end or opening is enclosed by a rigid plate member  582 . This member can be constructed from the same material as the remaining container (e.g. card stock, etc.). The member  582  is secured through the lower ends of the side walls  584  via slots or other structures defined on the container side walls. The member  582  can include a folded exterior tab or other handle  586  for gripping. When the member  582  is slid (arrow  588 ) out from under the dispensing end or opening, the stack  590  is released into the feed station  200 . Again, this container  580  can be adapted for mounting over the guides  202  and  204 . 
     FIG. 17 shows yet another embodiment of a container  600  in which a pair of folding triangular cross-section closures  602  (e.g. triangular truss/bracket shapes) are formed by folds in the side wall ends of the container. The closures support at least two opposing sides of the stack  604 . The closures can be pivoted (curved arrows  606 ) to the outwardly opened positions shown in phantom in the manner of bomb bay doors. This enables the stack  604  to be released onto the feed station, and the container to be slid over the guides if desired. The closures can be adapted to act as spacers to suspend the box end above and remote from the feed station feeder components/pathway as described generally above. This spacer function can also be accomplished by the container shown and described according to FIG.  13 . 
     Each of the preceding embodiments has described a container that defines a substantially fully enclosing box on at least four contiguous sides. FIGS. 18 and 19 illustrate an embodiment in which sheets are restrained by a non-enclosing structure that, nevertheless, selectively enables storage and transport of materials in a stack at first time, followed by dispensing of the materials into the feed station at a second time. 
     As shown in FIG. 18, a comb-like frame  620  defines a form of container/containment structure for storing and selectively dispensing envelopes according to an embodiment of this invention. The container structure  620  defines a spine  622  and a series of comb-like, flat projections  624 . Within the space  626  between each projection are located individual envelopes  628  and other sheet-like materials. The space  626  between projections  624  can be relatively small, assisting in holding the sheets therein by force or friction. The container structure  620  can be located so that it is disposed between selected guides to be removed after a stack is placed within the feed station  200 . 
     As shown in FIG. 19, the stack  630  when supported by the comb-like container structure  620  is lowered (arrow  632 ) into the feed, and the comb is removed (arrow  634 ). This enables the individual envelopes in the stack to lay atop each other free of intervention from the comb projections. 
     Another embodiment for containing and dispensing a stack is shown in FIG. 20 using a surrounding flexible binding member  650  (the “container” of this embodiment) that secures the stack  652  together for storage and shipment. The binding member  650  can be one or more flat ribbons, joined at its normally free ends with adhesive or another mechanical joint system. Alternatively the binding member  650  can be or one or more string/cord ties secured at free ends with a knots or secondary joint members (clamps, twist-ties, etc.). The free ends of the binding member  650  are joined at a securing location  658  that is conveniently located for removal by the operator—such as along a stack side that is readily reached at the feed station. In general the free ends are joined by any mechanism that firmly secures the ends  660  and  662  together until release is desired. The release mechanism can involve a forcible movement to cause release, or even a cutting action using a blade. 
     To dispense, the stack is first located over the feed station. The tie ends are released from each other (arrow  664 ), enabling the overall binding member  650  to be removed from the stack  652 . This usually occurs after the stack is loaded into the feed station along the guides so it does not lack side-support at any time. Because there is no separate side support provide by the container of this embodiment, the stack  652  is generally sized in depth no larger than the height of the guides  202  and  204 —unless guide extensions are provided to enable a higher stack to be accommodated at the feed station  200 . The binding member, in one or more pieces, can be easily slipped out from beneath the newly-deposited stack bottom after it is cut. 
     FIG. 21 illustrates yet another embodiment for containing and dispensing a stack of envelopes or other sheet-like materials. The stack  680  is joined together by a series of alternating, removable left tabs  682  and right tabs  684  that, in this embodiment, extend outwardly beyond the length LF of the feeder guides  202  and  204 . The tabs  682  and  684  define folds at their ends and are joined to adjacent envelopes in the stack  680 . A light removable adhesive can be applied to each of the tabs so that they pull easily from the envelopes to which they are joined using minimal tension. This adhesive can be similar in composition and performance to that available on popular self-adhesive memo/note pads that are commercially available. The tabs can be located so that they are positioned in the open space between guides. In this manner, they may project outward beyond the inner walls of the guides while the stack is deposited into the feed station. Tabs can be removed by a variety of techniques. For example, a pair of spines, shown generally by the dashed line elements  686  and  688 , can be firmly joined to the folds of each tab. In one embodiment, these spines can be constructed from paper or plastic ribbon adhered to the folds of the tabs  682 ,  684  or can be strings/cords that are passed through perforated holes at each tab. In any case, the tabs are typically removed once the stack is deposited into the feed station  200  as depicted by arrows  690 . Alternatively, the guides can be adapted to physically remove the tabs as the stack is driven down over the feed station. Appropriate mechanism for gathering, and disposing of, spent tabs are desirable in this example. 
     Finally, FIG. 22 illustrates an alternate embodiment of the invention, in which a container structure  700  defining a bottom  702  and, an enclosed end  704  is provided adjacent the feed station  200 . A secondary support  706  can be provided along the length of the bottom  702  to assist in supporting a container appropriately with respect to the feed station, or the container can include it&#39;s own internal support structure. Any acceptable bracket or support arrangement can be used to maintain the container  700  in place adjacent to the feed station. In fact, the container may be slightly canted downwardly toward the feed station in an alternate embodiment. A horizontal material/envelope stack  710  is located in the container. The stack is allowed to waterfall  712  into the primary feed stack  714  within the feed station through an open front end  716  of the container. The container  700  can be provided as a ready made unit with appropriate walls and guides, including a removable closure for the open front end  716  that enables the waterfall  712  to occur upon demand. Conversely, the container can be a fixed unit from which a large group of envelopes are deposited or carried from a separate storage container  720  as shown in FIG.  23 . As such, the envelopes  722  in FIG. 23 are moved or otherwise transferred as a large group (arrow  724 ) out of the container  720  and onto the extended feed container  700 . 
     FIG. 24 shows a feed station  800  for an envelope feeder or other sheet utilization device with a container or cassette receptor  802  according to an illustrative embodiment of this invention. The receptor  802  includes four upstanding walls  810 ,  812 ,  814 , and  816  that generally define a rectangle. In this embodiment, the opposing walls  810  and  812  engage the elongated edges of the envelope stack  818 , while the walls  814  and  816  engage the shorter side edges of the envelope stack. The wall  816  defines a U-shaped inverted metal bar that is adapted to enable the envelopes to pass thereunder in the direction of the arrow  820  to a feed location as described generally above. 
     The adjacent walls  810  and  816  in this embodiment are fixed so as to provide justifying locations for the envelopes so that they are aligned appropriately for entry into the downstream feed area of the utilization device. The walls  812  and  814  can be adjustable using appropriate adjustment members  824  that can include slides, cams or other locking mechanisms (such as the exemplary thumb screws  826  that interact with slots). In this manner, the walls  812  and  814  can be adjusted within a desired range of travel to accommodate varying sizes of envelopes or other sheet-like materials. The opposing walls  810  and  812  include, along their side edges, flexible strip members  830  and  832 , respectively. These flexible strip members will be described further below. In general, they project approximately the width of the container plus about one-half the clearance of the envelopes with respect to the box. They are relatively thin (5 mils to ⅛ inch in one example) and are constructed from a variety of materials. Generally, a thin, flexible-yet-rigid material is used, such as a polyvinyl chloride (PVC), rubber or another elastomer. However, brush bristles, hinge members or another mechanism can be substituted. The strips are typically formed from a solid strip of material from top to bottom. However, they can be provided with comb-like slits that define a series of fingers according to an alternate embodiment. 
     The wall  812  includes a sensor  840  interconnected with a controller or other component, which can be used to detect the presence of a cassette within the receptor. This sensor can be optical, acoustic, capacitance, or any other acceptable sensing technology. The sensor can also define a bar-code reader, or a radio frequency identification mechanism, that detects a specific indicia on the cassette to determine, for example, its type, capacity, any preprint information, or other identifying information. The sensor is connected to a controller or other data gathering circuitry (a networked computer, for example—not shown). 
     On the adjacent wall  816 , there is provided a block  842  that projects into the area of the envelope stack  818 . The block  842  can be moved laterally along a slot (double arrow  844 ) to accommodate differently sized or located lips on cassettes—as will be described further below. A thumb screw or other lock mechanism can be used to adjust and fix the block in an appropriate position for receiving the selected cassette. Note that a variety of block structures and shapes can be used that are specific to particular patterns and/or sizes of cassettes. In addition, a projecting box opener  846  comprising, for example, a box-cutting blade can be provided to the block  842  for enabling a cassette loaded onto the receptor to be slit and spread, thereby facilitating easier passage of envelopes therefrom onto the stack  818 . 
     FIG. 25 shows an exemplary cassette  900 , according to an illustrative embodiment of this invention, adapted to mate with the receptor  802  shown in FIG.  24 . It is expressly contemplated that the cassette  900  can be mated to alternate styles and types of receptors described above and otherwise contemplated by this invention. Similarly, the receptor  802  can receive a variety of cassette or container structures including those described herein and otherwise within the spirit and scope of this invention. The cassette  900  comprises a box structure generally constructed from cardboard or card stock (for example, corrugated cardboard), or a similar material having a sufficient wall thickness and strength to hold approximately 1,000 envelopes or other sheet-like materials. The internal structure of the cassette can be somewhat conventional in terms of its assembly and closure. For example, the edges can be folded and adhered or stapled together. Likewise, appropriate packing tape can be used. 
     Notably, the cassette  900  includes an overlapping flap  902  that, in this embodiment, is disposed on the outside of the box. However, it is contemplated that this edge can be placed inside the box in alternate embodiment. The flap  902  includes a finger cutout  904  that is optional. The flap  902  is tacked to the wall of the cassette so that it remains closed unless forcibly pried open. The tacking can be accomplished using intermittent glue spots, tape, staples or another suitable mechanism. The upper corner of the edge  906  is angled inwardly to prevent protrusion of the overlapping flap  902  beyond the top  910  of the cassette  900 . The lower edge  912  is also angled inwardly. However, it is offset from the bottom portion  914  of the box to accommodate a bottom end opening mechanism  916 . According to one embodiment, this mechanism consists of a pull tab  920  cut from the outer skin of the box, and adhered to a tear tape  922  (shown in phantom) of somewhat conventional design. The tear tape  922  in this embodiment comprises a sturdy piece of nylon strip or string that, when an outward pulling force is applied to the tab, causes the drawn tear tape to shear the cassette material so as to fully separate the bottom portion  914  along the tape line from the remaining upper portion of the cassette box. 
     As shown in FIG. 26, the cassette  900  is suspended over the receptor  802 , having had its bottom portion  914  removed (arrow  930 ). The cassette  900  is, thus, lowered (arrow  930 ) onto the receptor so that it is engaged by the side walls  810 ,  812 ,  814 , and  816 . 
     As noted above, the cassette  900  is justified against the walls  810  and  816 . The block  842  is set so that it bears against the raised edge  942  of the overlapping flap  902  of the cassette. In this manner, the block prevents the cassette from being inserted in any other orientation, thus ensuring that all envelopes are provided with the proper justification into the stack  818 . Envelopes from the cassette are held in place by a finger or other retainer after the bottom portion  914  is removed, but before the cassette is placed fully into the receptor into communication with the top  950  of the preexisting envelope stack  818 . Alternatively, a temporary retaining structure of a form described above or otherwise within the spirit and scope of this invention can be manually released or automatically actuated by an appropriate structure within the receptor  802  to cause envelopes to drop into the lower stack  818 . 
     Note that the cassette  900  is suspended at a distance above the lower, preexisting stack  818  so as to not interfere with any output envelopes (note arrow  820 ) at the base of the stack. As the cassette  900  is lowered into the receptor, the cutter  846  may slit and spread the lower portion of the cassette at its point of contact with the cutter  846  to provide space for exiting envelopes, and to reduce friction generated by the cassette interior side walls. 
     Note also that the receptor wall  814  includes an angled lower edge  958 . This angled edge is disposed at an angle of approximately 45 degrees to 85 degrees (but this is highly variable). The edge  958  engages the bottom edge  960  of the cassette when the cassette is lowered fully into position. The angle serves as a variable stop for the bottom edge  960  so that variations in the size of the cassette with respect to the receptor can be accommodate within a certain range while still suspending the cassette at a desired distance above the base of the stack  818 . In addition, the edge helps to force the cassette into justification against the opposing fixed wall  816 . As shown clearly by the bias of the strip  832  along the wall  812 , a bend  970  is developed near the bottom edge  960  of the cassette. This bend transitions between an inwardly disposed portion  972  of the strip (adjacent the cassette side) and an unbent portion  974  of the strip (adjacent the lower stack  818 ). The strips  830  along the opposing wall  810  are also similarly bent. In this manner, the strips  830  and  832  firmly secure the cassette in place while it is mounted in the receptor, but enable the stack below the bottom edge  960  of the cassette to be properly justified by the outward edges of the strips  830  and  832 . At the bend  970  a gradual transition is made that assists in guiding the envelopes into a properly justified position within the lower portion of the stack from their floating orientation between interior side walls of the cassette. As noted above, a more-abrupt transition can be generated if a series of fine slits are cut along the length of the strips to generate a comb-like structure. This arrangement may be desirable according to an alternate embodiment. Accordingly, the term “flexible strip” should be taken broadly to include any such structure that selectively bends to accommodate displacement by the cassette while remaining straightened at some location below (adjacent to the lower stack  818 ). 
     The receptor opposing receptor walls  810  and  812  are typically adjusted (moving wall  812  as appropriate) so that they firmly confront the outer faces of the cassette  900 . These walls thus serve to firmly locate and justify the cassette along the axis therebetween, and correct any skew in the box structure by forcing the walls into line. The adjacent wall  814  and edge  858  further corrects skew in this manner. In general it is contemplated that at least two adjacent or opposing surfaces that apply normal forces to the walls of the cassette can be employed as a receptor according to this invention. 
     It should be clear that the receptor  802  functions without the presence of a cassette to feed a stack of a certain size, delimited by the height of the walls  810 ,  812 ,  814  and  816 . Appropriate readjustment of one or more walls may be desired to better fit the stack without a cassette attached. 
     Some further variations of the cassette structure and dispensing arrangement will now be described. FIG. 27 shows a cassette  1000  in which the envelopes or other sheet-like materials  1002  are dispensed from the cassette&#39;s bottom edge  1004  in an on-end configuration. In this embodiment at least a portion of the stack is dispensed to the feed station “simultaneously.” This means that a group of envelopes/sheet-like materials is dispensed en masse to the appropriate site in the feed station. This can be desirable where a feeding arrangement such as shown in FIG. 22 is employed. The bottom edge  1004  can be open prior to loading (e.g. while still upright), so that dispensing occurs when the cassette is flipped over, or the bottom edge can be closed using a variety of closure/release methods and mechanisms described herein—including the tear tape of FIG.  25 . It is noted that certain utilization devices employ an auto-load principal in which on-edge envelopes/sheet-like materials are deposited on a conveying structure  1006  so that they become shingled over one another once they are deposited. The cassette  1000  of this embodiment particularly facilitates batch-loading of such a device&#39;s conveyor. In particular, the Bell &amp; Howell 4000 series employs such an auto-loader, and this cassette  1000  can be adapted specifically for use with such a device. 
     FIG. 28 shows another embodiment of a cassette  1100  in which envelopes or other sheet-like materials  1102  are dispensed from a partially opened bottom end  1104 . The partial opening has a distance DO that is sufficient to enable the bottommost envelope/sheet-like material  1106  to engage a mechanical, vacuum or other extraction mechanism (for example, the wheel  1108 ) so as to move (arrow  1110 ) the bottommost envelope/sheet-like material out of the opening. The extraction technique can include direct sliding or a peeling-down motion (as shown), or any other motion that effectively removes the bottommost envelope/sheet-like material  1106  from the opening. 
     Finally, FIG. 29 shows a further variation of a dispensing technique for a basic box-like, open-bottomed cassette  1200 . This cassette can be opened along its bottom edge  1202  using a variety of techniques described herein, and otherwise contemplated within the spirit and scope of this invention. This cassette  1200  is located at an angle AD that is non-perpendicular with respect to the plane  1204  of a feed surface  1206  (moving or stationary). In this manner, an angular opening is created with respect to the feed surface is by which envelopes are moved downwardly (arrow  1206 ) and outwardly  1208  away from the cassette&#39;s bottom edge opening in a more-efficient manner. This techinique assumes that singulating of envelopes or other sheet-like materials from the cassette occurs at a later time, downstream of the cassette  1200 . Alternatively, the cassette can be placed perpendicularly so that the angle AD is, in fact, 90 degrees and an angled opening  1220  (shown in phantom) can be defined on the cassette bottom. The cassette  1200  can be provided with a separate tear tape or other mechanism (a perforation, for example) for selectively defining either a flat perpendicular bottom or angled bottom as shown. Alternatively, the cassette can have either a perpendicular bottom or angled bottom exclusively. All of the cassettes described herein can include the above-described overlapping side to enable random access to the entire length of the cassette for more-conventional access of the contents. 
     The foregoing has been a detailed description of numerous embodiments of the invention. Various other additions and improvements can be made without departing from the spirit and scope of this invention. For example, containers or other storage mechanisms described herein can include a variety of additional features for aiding in loading, unloading, stacking and storing of the materials therein. In particular, containers can include a variety of different flaps and covers that can be accessed for different purposes. One purpose can be to enable to container to be used as a conventional storage container in which envelopes or other sheet-materials are removed in small bundles by hand. This can include providing an elongated flap along one side of the container that can be opened to reveal the entire stack on edge. It is also expressly contemplated that a variety of different feed station elements can be provided to assist in the support and loading of containers, as well as the use of the feed station in a conventional manner in which individual bundles are transferred by hand. Significantly, the term “stack” should be taken broadly to include a variety of different groups of envelopes/sheet-like materials that are fed to a utilization device (including, but not limited to, edge-on groups, shingled feed arrangements, and the like). Finally, while the stack contents of various containers described herein are shown as released in their entirety in a single operation, it is expressly contemplated that less than the entire contents of a container can be dispensed at one time by the selective, controlled actuation of the container release mechanism. It is should be clear that the beneficial effects of this invention continue to be enjoyed even where less than the entire contents are dispensed, namely—minimal direct operator intervention, and more assurance of proper stack orientation. Accordingly, this description is meant to be taken only by way of example, and, not to otherwise limit the scope of this invention.