Abstract:
A multi-user mail box including a letter drop assembly which is susceptible to easy replacement by a delivery person without requiring substantial disassembly of the mail box. The letter drop assembly includes a slotted body held in inserted relation between cross-bars extending transverse to vertical frame members of an access door structure. The slotted body includes upper and lower open grooves oriented in opposing relation to the adjacent cross-bars. Retention pin elements are inserted axially into the grooves thereby holding the slotted body in place. The slotted body may be replaced by displacement of the retention pin elements.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
   This application claims the benefit of and priority from U.S. provisional application 61/068,315 filed Mar. 6, 2008 in the name of James R. Bond, the contents of which are hereby incorporated by reference in their entirety as if fully set forth herein. 
   TECHNICAL FIELD 
   This patent disclosure relates generally to mail box units and, more particularly, to multi-unit mail box structures having one or more built-in letter drops accessible for the deposit of letters and/or packages by users from the exterior. 
   BACKGROUND 
   In many environments, mail in the form of letters and/or packages is received at a central location using containment structures having multiple storage receptacles. Typically, these storage receptacles are individually accessible by users through the use of keys, combination locks or other access mechanisms as will be well known to those of skill in the art. Such containment structures are typically referred to as central box units or “CBU&#39;s”. In this regard, it is to be understood that the term “mail” is intended to include not only governmental postal delivery but also to delivery of letters and/or packages by non-governmental entities. Thus, it is intended that units consistent with this disclosure may find application in both governmental and non-governmental delivery systems. 
   Central box units typically include one or more deposit slots for general use by persons wishing to have letters and/or packages picked up for subsequent delivery to another location. Such deposit slots are generally constructed to avoid incursion by the elements. However, they must also be sufficiently accessible to permit relatively easy deposit. Deposit slots may be prone to damage during the life of the central box unit due to the relatively high levels of use, misuse, and/or theft attempts. Historically, when a deposit slot has been damaged, it was necessary to engage in a relatively complex disassembly of the central box unit to fix the damaged slot. This disassembly and repair operation often involved the removal of an entire access door or other large structure and was generally beyond the capabilities of the regular delivery person. 
   SUMMARY 
   The present invention offers advantages and alternatives over the prior practices by providing a letter drop assembly adapted for use within a central box unit which is susceptible to easy replacement by a delivery person without requiring substantial disassembly of the central box unit. The letter drop assembly includes a slotted body held in inserted relation between cross-bars extending transverse to vertical frame members of an access door structure. The slotted body includes upper and lower open grooves oriented in opposing relation to the adjacent cross-bars. Retention pin elements are inserted axially into the grooves thereby holding the slotted body in place. The slotted body may be replaced by displacement of the retention pin elements. 
   According to one aspect, a multi-user mail box unit including at least one deposit opening is provided. The mail unit includes multiple individually accessible interior storage compartments. At least one general access door is adapted to open and close in relation to the interior. The general access door includes an inboard vertical frame member and an outboard vertical frame member. At least one removable letter drop assembly is supported within the general access door between a first crossbar and a second crossbar. The first crossbar and the second crossbar are in spaced relation to one another and extend between the inboard vertical frame member and the outboard vertical frame member. The letter drop assembly includes a body portion having a length dimension oriented transverse to the inboard vertical frame member and the outboard vertical frame member. The body portion includes a slot defining the deposit opening. The body portion includes a first open groove extending in the length dimension along an upper edge of the body portion. The first open groove is in opposing relation to the first crossbar. The body portion includes a second open groove extending in the length dimension along a lower edge of the body portion. The second open groove is in opposing relation to the second crossbar. A displaceable first elongate pin element normally extends across the inboard vertical frame member and axially through the first open groove. The first elongate pin element includes a first distal tip normally projecting into a first receiving opening within the outboard vertical frame member. The first elongate pin element is axially moveable within the first open groove. The first open groove is adapted to block radial displacement of the first elongate pin element when the first elongate pin element is within the first open groove. A displaceable second elongate pin element normally extends across the inboard vertical frame member and axially through the second open groove. The second elongate pin element includes a second distal tip normally projecting into a second receiving opening within the outboard vertical frame member. The second elongate pin element is axially moveable within the second open groove. The second open groove is adapted to block radial displacement of the second elongate pin element when the second elongate pin element is within the second open groove. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The following drawings which are incorporated in and which constitute a part of this specification illustrate several exemplary embodiments and constructions consistent with this disclosure wherein: 
       FIG. 1  is a face view of an exemplary central box unit including a removable letter drop assembly; 
       FIG. 2  is a view similar to  FIG. 1 , with access doors in an open position; 
       FIG. 3  is an exploded perspective view illustrating an exemplary letter drop assembly consistent with the present disclosure; 
       FIG. 4  is an exploded perspective view illustrating a subassembly of the removable letter drop assembly in  FIG. 3  incorporating a slotted body panel and a slidably insertable anti-fishing security screen; 
       FIG. 5  is perspective view of an exemplary anti-fishing security screen; and 
       FIGS. 6A-6C  illustrate several exemplary alternative geometries for elongate locking pin elements. 
   

   Before the exemplary embodiments of the invention are explained in detail, it is to be understood that the invention is in no way limited in its application or construction to the details and the arrangements of the components set forth in the following description or illustrated in the drawings. Rather, the invention is capable of other embodiments and being practiced or being carried out in various ways. Also, it is to be understood that the phraseology and terminology used herein are for purposes of description only and should not be regarded as limiting. The use herein of terms such as “including” and “comprising” and variations thereof is meant to encompass the items listed thereafter and equivalents thereof as well as additional items and equivalents thereof. 
   DETAILED DESCRIPTION 
   Reference will now be made to the drawings wherein to the extent possible, like elements are designated by like reference numerals throughout the various views.  FIG. 1  illustrates an exemplary central box unit or “CBU”  10  such as may be used to collect mail at a central location such as an apartment lobby or the like. As shown, the central box unit  10  includes a number of discreet user boxes  12  of various size and shape. The user boxes  12  may be accessed by individual users using keys to engage locks  14  in a manner as will be well-known to those of skill in the art. Of course, other access techniques such as combination locks, electric locks and the like may also be used, if desired. 
   In the illustrated exemplary construction, the central box unit  10  also includes at least one so-called letter drop  16  including a slot opening  18  adapted to receive letters, post cards, small parcels, and the like for subsequent pick up by a delivery person. In this regard, it is to be understood and appreciated that in this application the term “mail” is in no way limited to governmental postage. Rather, it is intended that the present invention shall include and extend to any public or private delivery system as may be desired. Moreover, while the central box unit  10  is illustrated as having two generally vertically oriented cabinets, such a construction is merely exemplary and any number of other configurations may be utilized as desired. By way of example only, and not limitation, a larger or smaller number of user boxes may be arranged in a larger or smaller number of cabinet structures. 
   As illustrated in  FIG. 2 , the central box unit  10  includes an arrangement of general access doors  20  that are adapted to be opened by a delivery person to gain access to the interior compartments of the user boxes  12 . By way of example only, and not limitation, this opening may be carried out by use of a master door latch  22  ( FIG. 1 ) which may be manipulated by a delivery person. Such master door latches are well-known to those of skill in the art and form no part of the present invention. 
   As illustrated in  FIG. 2 , individual access doors  30  for each of the user boxes  12  are separated by cross bars  26 . The cross bars  26  extend across the general access doors  20  between an inboard vertical frame structure  28  and an outboard vertical frame structure  29 . The inboard vertical frame structure  28  and the outboard vertical frame structure  29  extend generally along the length of the general access doors  20 . The cross bars  26  provide support for the individual access doors  30  that are used to gain access to individual interior compartments  32 . The cross bars  26  also project inwardly to a degree to separate the individual interior compartments  32  from one another when the general access doors  20  are in a closed position. 
   As indicated previously, the central box unit  10  includes at least one letter drop structure  16  configured to accept deposit of letters or the like. In accordance with a feature of the present invention, the letter drop structure  16  is adapted for easy removal and replacement by a delivery person when the general access doors  20  are in the open position as illustrated in  FIG. 2 . By way of example only, and not limitation, an exemplary removable letter drop assembly is illustrated in  FIG. 3  in relation to sections of the inboard vertical frame member  28  and the outboard vertical frame member  29 . As illustrated, the exemplary letter drop structure  16  includes a slotted body  40  having a length and width substantially corresponding to the shape of the individual access doors  30  for the individual user boxes  12 . Thus, the slotted body  40  may be positioned between complimentary crossbars  26  in spanning relation to the inboard vertical frame member  28  and the outboard vertical frame member  29 . 
   As shown, the slotted body  40  includes an angled rain guard  42  extending in covering relation to the slot opening  18 . The slotted body  40  also includes a pair of rearwardly extending leg members  44  disposed in generally opposing relation to the adjacent crossbars  26 . In the illustrated configuration, the space between the leg members  44  defines a channel for sliding insertion of a anti-fishing security screen  46  as will be described further hereinafter. As shown, the rearwardly extending leg members  44  include open grooves  50  extending along the length dimension of the slotted body  40 . The open grooves  50  are disposed along the upper edges of the rearwardly extending leg members  44  facing towards the adjacent crossbars  26 . 
   In the illustrated exemplary construction, the open grooves  50  are disposed in opposing relation to complimentary grooves disposed along the surfaces of the opposing cross bars  26 . In the exemplary configuration, the open grooves  50  are configured to accept and retain the legs of an insertable pin member  56 . Specifically, in the illustrated construction, the legs of the pin member  56  define elongate pin elements that may be inserted through inboard access openings  58  disposed at the inboard vertical frame member  28 . The distal ends of the legs on the pin member  56  are then passed into the corresponding open grooves  50  in aligned relation with the inboard access openings  58 . The open grooves  50  are sized to extend partially but not completely about the legs of the pin member  56 . In this regard, the cross-sectional geometry of the open grooves  50  is set such that the legs of the pin member  56  may be pushed axially along the length of the open grooves  50 . However, the legs of the pin member  56  are blocked against moving radially out of the open grooves  50 . 
   By way of example only, and not limitation, according to the illustrated construction, entrapping engagement between the open grooves  50  and the legs of the pin member  56  may be achieved by providing the open grooves  50  with a partial circular profile such that the walls of the grooves extend around an angle greater than about 180°. Thus, when the legs of the pin member  56  are inserted axially into the open grooves  50 , the walls of the grooves extend upwardly beyond the centerline of the legs on the pin member  56  to block outward movement. Of course, it is likewise contemplated that other pin-retaining arrangements may be used such as using open grooves with angled profiles corresponding to legs with angular cross-sections to permit axial insertion while restricting radial withdrawal of the legs. In this regard, while the cross-sectional geometry of the open grooves  50  may be in the form of a partial circle adapted to accept substantially round legs, it is contemplated that other cross-sectional geometries may likewise be used to accept other pin geometries as may be desired. By way of example only and not limitation such alternative geometries may include a square or rectangular cross-sectional pin element  156  with substantially straight planar surfaces ( FIG. 6A ); a square or rectangular cross-sectional pin element  256  with an undulating surface ( FIG. 6B ); and a triangular cross-sectional pin element  356  with substantially straight planar surfaces ( FIG. 6C ) or undulating surfaces (not shown). Each of these may be inserted into an open groove of substantially complementary cross-section. Of course, any number of other cross-sectional geometries may also be used. 
   As illustrated through reference to  FIG. 3 , in the final assembled condition the distal ends of the legs on the pin member  56  ultimately extend axially beyond the open grooves  50  and into outboard acceptance openings  60  at the outboard vertical frame member in aligned relation with the axis of the open grooves  50 . As will be appreciated, once the legs of the pin member  56  have been fully inserted, the slotted body panel is held in secure relation between the inboard vertical frame member  28  and the outboard vertical frame member  29 . The adjacent crossbars  26  are disposed in covering relation to the legs of the pin member  56  and are held in place by screws or other attachment means (not shown) as may be desired. 
   In the illustrated exemplary construction, the pin member  56  is characterized by a generally “U” shaped configuration with two legs projecting away from a substantially straight cross member. As will be appreciated, such a construction permits a delivery person or other person servicing the letter drop  16  to grasp the cross member as a handle during insertion and removal of the pin member  56 . Of course, pin members with other constructions may likewise be utilized. By way of example only, and not limitation, other generally “U” shaped configurations incorporating finger loops at the cross member may be utilized. Individual straight pins with flared heads that can be grasped by a user may also be used if desired. 
   Referring now to  FIG. 4 , it may be seen that in the exemplary construction a panel acceptance channel  60  is disposed across a rear surface of the slotted body  40 . As indicated previously, the panel acceptance channel  60  is configured to slidingly accept insertion of the anti-fishing security screen  46 . As shown in  FIG. 4 , the panel acceptance channel  60  includes a pair of inwardly extending ears  62  extending along the length of the slotted body  40 . The inwardly extending ears  62  are spaced apart from the rear face of the slotted body  40  such that the anti-fishing security screen  46  may slide between the inwardly extending ears  62  and the rear face of the slotted body  40 . In this arrangement, the inwardly extending ears  62  serve to prevent the anti-fishing screen  46  from falling out of position. 
   As illustrated, the anti-fishing security screen  46  includes a window opening  68  which is oriented for substantial alignment with the slot opening  18  in the slotted body  40 . Thus, in the assembled condition, a letter or parcel may be inserted through the aligned slot opening  18  and the aligned window opening  68 . As seen through joint reference to  FIGS. 4 and 5 , the anti-fishing screen  46  also includes an arrangement of teeth  70  projecting in downwardly angled relation away from the window opening  68 . The teeth  70  provide a barrier against the insertion and manipulation of a wire or other elongate structure to reach and retrieve articles that have been deposited through the slot opening  18 . The presence of the teeth  70  may also provide a ramped surface useful in carrying deposited envelopes to a rearward position. 
   One potential benefit of the illustrated and described construction is the ability to form the slotted body  40  substantially by extrusion techniques. In this regard, it will be noted that the rain guard  42 , the open grooves  50 , and the panel acceptance channel  60  may all be formed during an extrusion process. The use of such extrusion processing may promote substantial efficiency during the formation process. 
   Another potentially beneficial feature of the illustrated and described construction is the ability to rapidly remove and replace the letter drop structure  16  in the event of damage. In this regard, it will be appreciated that when the general access doors  20  are in the open position as shown in  FIG. 2  the pin member  56  is readily accessible. By simply removing the pin member  56 , the engagement between the slotted body  40  and the inboard and outboard vertical frame members  28 ,  29  is released. Without this engagement, the slotted body  40  may be easily removed by grasping the rain guard  42  or other portion and pulling outwardly. Thereafter, a replacement slotted body  40  may be inserted and locked in place by reinsertion of the pin member  56 . 
   Of course, it is contemplated that any number of other structures and combinations may likewise be utilized. In this regard, it will be appreciated that the foregoing description and drawings provide exemplary embodiments. However, it is contemplated that other implementations of the disclosure may differ in detail from the foregoing examples. Accordingly, this disclosure contemplates the inclusion of all modifications and equivalents of the subject matter disclosed herein as permitted by applicable law. Moreover, any combination of the above-described elements in all possible variations thereof is contemplated unless otherwise indicated herein or otherwise clearly contradicted by context. 
   Various features of the invention are set forth in the following claims.