Abstract:
Public storage lockers are designed particularly for storage of bicycles, such as at a public transportation terminal. In a preferred embodiment the storage lockers are on-demand, lockable by a user who must unlock the locker using the same electronic key and who must unlock the locker before using the key for any other locker. The lockers are visually open, with a secure screen or mesh on the locker door and optionally on walls and top cover. This reveals that the bike locker is occupied and prevents the use of the locker for unauthorized, privacy-requiring activities. The bike enclosure has a floor wheel guide for conveniently loading the bike, and a special door latch mechanism which provides for security by including a latch bar in a fixed frame, while a latch bar lifter, operable to permit door opening when the lock is unlocked, is on the door. The door lock is always locked, in an available locked mode or an unavailable locked mode, except when unlocked for only a few seconds before the lock automatically locks down the latch bar again, so the door is locked as soon as re-closed. LED status indicator lights can be included. Preferably the lock and the electronic keys have logic which prevents use of the key if the user fails to reopen the lock within a prescribed period of time, and other safeguards.

Description:
SPECIFICATION  
       [0001]    This application is a continuation-in-part of application Ser. No. 09/591,210, filed Jun. 9, 2000, which claimed priority under provisional application Serial No. 60/138,304, filed Jun. 9, 1999. 
     
    
     
       BACKGROUND OF THE INVENTION  
         [0002]    The invention concerns public on-demand storage lockers, and in a specific embodiment, bicycle lockers such as may be used to store bicycles at a public transportation station. The invention has several aspects, including the manner of fabrication of the storage lockers, the secure latching mechanism and an electronic locking system.  
           [0003]    The need for a highly secure, highly vandal-proof, on-demand public storage locking system is readily apparent. For example, in response to user demand, Bay Area Rapid Transit in the San Francisco Bay Area recently installed a large number of bicycle lockers with hasps designed to accommodate user-supplied locks. Unfortunately, these lockers have suffered from use as homeless shelters, fires as a consequence of homeless use, poor security characteristics due to the ease with which prying tools can be used when user-supplied mechanical locks are exposed, concern by police about potential for bomb planting, high maintenance costs due to lock clipping and locker cleaning requirements, and prevention of general availability by users who keep their locks on the lockers even when they are not storing a bike.  
           [0004]    Standard coin/key locker locking systems have been tried for bike lockers (by the City of Palo Alto, Calif. for example), but have proven too vandal and damage-prone, and require lock cylinder changing when keys are lost.  
           [0005]    High security mechanical key locks have proven successful for bike lockers, but require a long-term rental commitment by users and generally do not permit a single locker to be used by multiple users on an on-demand basis, or for a user to secure a bike at different locations.  
           [0006]    Double mechanical lock systems (one individual user-supplied lock and one built-in lock which opens to any issued key) are successful in allowing multiple users access to all available lockers, but are successful overall only in situations where security among key-issued users is relatively high, such as within a company. These systems are not well suited to truly public settings, such as transit stations.  
           [0007]    Most public storage lockers, whether on-demand lockers or long-term lockers, have inadequate security against vandalism, theft by breaking open the locker door, or jamming of the lock to an unlocked position. Typically, the latch mechanism, as well as the lock itself, is mounted on the door, in a manner that is not totally secure, leaving parts of the mechanism accessible when the door is open.  
           [0008]    It is desirable for a public locker system to be set up for on-demand use, to be always locked except when unlocked for access, which is for only a few seconds, to be easily accessed by a key, preferably electronically, and to be visually open so as to preclude privacy, hiding or storage of unauthorized materials, and discourage unauthorized activities. These are objects of the invention described below.  
         SUMMARY OF THE INVENTION  
         [0009]    These goals are addressed by the invention described below, wherein public storage lockers are designed particularly for storage of bicycles, such as at a public transportation terminal. In a preferred embodiment the storage lockers are on-demand, lockable by a user who must unlock the locker using the same electronic key (or PIN for a keypad, both of which may be referred to herein as “key device”) and who must unlock the locker before using the key for any other locker. In the preferred embodiment, the lockers are visually open, with a secure screen or mesh on the locker door and optionally on walls and top cover. This reveals that the bike locker is occupied and prevents the use of the locker for unauthorized, privacy-requiring activities, or storage, or hiding of a bomb. Preferably the bike enclosure has a floor wheel guide for conveniently loading and unloading the bike and to maintain an orderly appearance.  
           [0010]    A special door latch mechanism provides for security by including a latch bar in a fixed frame, while a latch bar lifter, operable to permit door opening when the lock is unlocked, is on the door. The door also has one or more angled, camming latch hooks, which penetrate the frame through slots to momentarily lift a spring-loaded or gravity-actuated latch member connected to the latch bar in a camming action when the door is closed. In another embodiment the camming latch on the door is permitted spring-loaded movement, camming over a surface of the latch bar when the door closes, and lifting clear of the larch hook when the latch bar is lifted in the unlocked mode. Thus, the door lock is always locked, in an available locked mode or an unavailable locked mode, except when unlocked for a only a few seconds before the lock automatically locks down the latch bar again, so the door is locked as soon as re-closed. LED indicator lights show whether the locker unit is in the available locked mode or the unavailable locked mode.  
           [0011]    Preferably the electronic lock and keys have logic which prevents use of the key if the user fails to reopen the lock within a prescribed period of time, and other safeguards against user abuse.  
           [0012]    In a specific embodiment the electronic keys are of the iButton type, which are merely touched to a designated spot on the lock in order to cause retraction of a bolt by a solenoid in the preferably battery-powered electronic lock, provided access criteria are met. If battery-powered, the lock enjoys a long battery life because the only mechanical movement performed in the lock is to retract a small bolt which normally blocks movement of the latch bar. The lifting of the latch bar and the opening of the door are performed manually by the user. The locks can be wired and powered externally if desired, facilitated by location of the lock in the frame (which is not possible in a secure and economical manner with the normal latch bar, lifter and lock in the door).  
           [0013]    The cage is a heavy steel angle frame approximating the shape of a slice of pie in one preferred embodiment. Diagonal members on the sides can be added to provide additional strength and security. The cage can be bolted to the ground, to other cages side by side and/or to another cage stacked on top. Cages can be combined to create a partial or full circle, linear or sawtooth pattern. In a preferred embodiment, the cage also provides a secure enclosure for the automated elements. In the preferred embodiment, the cage design can support the installation of the automated elements in two different positions so that lockers can be stacked and the lock release mechanism is in reach for both upper and lower units.  
           [0014]    The door is also constructed from a strong frame designed to be rigid against in- and out-of-plane bending when pried. It is attached to the cage with a hinge using a continuous piano hinge in the preferred embodiment. The door has rounded edges and fits into the surrounding cage frame, also with rounded edges, as it closes to prevent prying.  
           [0015]    A secure enclosure is required to house the automated elements to prevent against tampering. A competing requirement is the infrequent requirement of accessing the automated elements for maintenance. These requirements are met by permitting access to the secure enclosure only when the Locker is open, and by using standard techniques such as cam locks in the preferred embodiment, tamper-proof screws, or a small hasp and lock to attach the access cover of the secure enclosure, accessible only from inside the locker.  
           [0016]    In the preferred embodiment optimized for bicycle storage, a wheel guide bisects the bottom of the cage. Like wheel guides used in bicycle storage racks for retail stores, the open, reentrant corners are oriented inward to accept the bicycle tire. This element facilitates loading and unloading a bicycle. It also creates a rugged surface on the floor that impedes using the cage as place to rest or sleep.  
           [0017]    A heavy chain with vinyl cover and large ring may be attached to the frame in the locker for additional security. This enables the user to secure the bike frame and wheel(s) using the chain and a user-supplied bike lock fit into a large ring on the end of the chain.  
           [0018]    The infill creates the walls of the cage and door. Expanded metal or mesh is attached to the frame, providing structural support and securing the contents while still allowing visibility into the cage. Alternatively, strong and secure transparent solid plastic sheets or virtually any other panel material having the required transparency can be used. Transparent sheets can be reinforced with glass fibers. In a preferred embodiment, additional interior members are added which would require a different tool to compromise, further impeding removal of contents even if the infill is compromised.  
           [0019]    A powder-coated, galvanized or similar finish should be applied to the cage, door and infill for long term wear and weathering, or the cage can be constructed out of stainless steel. A weatherproof top can be used when the lockers are installed outside, without a secondary roof overhead.  
           [0020]    The automated locking system is what allows the user to lock the door of the cage, and comprises both manually powered elements and automated elements. The automated elements control the user&#39;s ability to operate a secondary multi-point door latching system which secures the door to the cage.  
           [0021]    In the preferred embodiment, the hardware that secures the door to the cage uses, in part, a standard multi-point latching system often found in wardrobe lockers. The user provides the power to open and close the latch using a pry- and push-protected handle. The automated elements control a bolt that enables and disables the latching system.  
           [0022]    In one embodiment, rechargeable batteries provide power, supported by an external standard A/C line running a trickle charger. This allows the lockers to operate in the event of a power outage, and requires less maintenance than a battery-only system. An external port for a 9-volt DC power probe is provided that the lock can be operated by “jumping” power even when the batteries have expired or the supply system is down.  
           [0023]    A communications port can be installed on the logic board of the electronic lock, to report activity and current status of all lockers. Depending on its intended use, the port can be installed to be accessed from the front of the unit, from the inside of the unit, from inside the secure steel box, or it can be wired directly to an external connection, such as a telephone line or a separate communications hub for a bank of lockers, so information or control of the lock mechanisms on all lockers can be accessed from a single location. Preferably the user is prevented by the electronics from using more than one locker at a time.  
           [0024]    The locker is in a locked available mode or a locked unavailable mode at all times, except when momentarily unlocked, and the user has no power to extend the momentarily unlocked mode, which is only a few seconds. LEDs on the locker may operate to indicate status to users or potential users or to officials. For example, different colors can be used for different status (locked/available, locked/unavailable, expired usage period, out of order), or flashing or solid for different status. When the electronic key is touched to the electronic keypad on the lock, a solenoid or micro-motor retracts the lock bolt, allowing the user to lift the latch bar and open the door. The user then puts his bike inside the locker. The LED may flash as long as the lock is retracted. When the user closes the locker door, this status is indicated by the LED(s), indicating the locker is secured and in use. Once in this locked/unavailable mode, the locker can be opened once by the same user key. Once re-accessed, the lock reverts to the available mode, so indicated by LED.  
           [0025]    If the locked/unavailable mode lasts for more than a certain period of time (such as, for example, one week for a bicycle locker), then the LED may so indicate, and a different electronic key is required to open the locker, the user&#39;s key being no longer effective, or to reset the lock allowing the user&#39;s key to work again. The different key may be in the hands of the police or a key-issuing agency, normally municipal or other government agency. This provides a deterrent to those who would monopolize lockers for long-term storage, as well as a mechanism for police or other officials to impound offending bikes, or to ticket offenders.  
           [0026]    As noted above, the electronic lock can include a read/write memory capable of tracking usage of a locker, including blocking modes, and to report real time status of a large number of lockers, through wiring to a central facility or by telephone or other access.  
           [0027]    A red LED mode (or another special mode) may be included on the lock, to indicate when the locker is out of order.  
           [0028]    For security the door preferably is spring-loaded so as to be self-closing even if not deliberately closed by the user. Closing of the door is effective to cam and reset one or more latch members associated with the latch bar, securely locking the door.  
           [0029]    Instead of being constructed in the way known prior art storage lockers, using sheet metal panels attached together, or molded materials, another important feature of this invention is that the infill panels are attached to a metal framework, allowing for greater flexibility in selecting transparent, translucent, opaque, metallic or non-metallic materials in any combination for the sides and top of the locker. The framework system also allows for flexible arrangement and ganging of the lockers without special party walls and/or end walls as are required in many bike locker systems.  
           [0030]    It is thus among the objects of the invention to provide a conveniently used, highly secure, tamper-resistant and abuse-resistant on-demand or individually assigned locker, latch and lock mechanism, particularly adaptable for bicycle storage at a public transit facility. These and other objects, advantages and features of the invention will be apparent from the following description of a preferred embodiment, considered along with the accompanying drawings. 
       
    
    
     DESCRIPTION OF THE DRAWINGS  
       [0031]    [0031]FIG. 1 is a perspective schematic view showing an embodiment of a bicycle locker according to the invention.  
         [0032]    [0032]FIG. 2 is a plan view showing the bicycle locker of FIG. 1.  
         [0033]    [0033]FIG. 3 is an elevational section view showing a latch mechanism of the locker.  
         [0034]    [0034]FIG. 3A is a view showing a latch bar of the lock mechanism, in an elevation at right angles to the view in FIG. 3.  
         [0035]    [0035]FIG. 4 is a partial view showing the front of the locker, showing an electronic lock in the frame, and showing a corner of the closed door.  
         [0036]    [0036]FIG. 5 is an enlarged view showing an upper portion of FIG. 3.  
         [0037]    [0037]FIG. 5A is a view similar to FIG. 5 but showing a modified latch embodiment.  
         [0038]    [0038]FIG. 6 is a sectional plan view showing a portion of the locker assembly.  
         [0039]    [0039]FIG. 6A is a view similar to FIG. 6 but showing the embodiment of FIG. 5A.  
         [0040]    [0040]FIG. 6B is another similar section view, taken lower in the assembly.  
         [0041]    [0041]FIG. 6C is an exploded perspective view showing a latch unit included in the arrangement of FIGS. 5A and 6A.  
         [0042]    [0042]FIG. 7 is another sectional plan view showing a portion of the assembly.  
         [0043]    [0043]FIG. 8 is another sectional plan view showing a portion of the assembly.  
         [0044]    [0044]FIG. 9 is another sectional plan view showing a portion of the assembly. 
     
    
     DESCRIPTION OF PREFERRED EMBODIMENTS  
       [0045]    In the drawings, FIG. 1 shows a bicycle locker  10  according to a preferred embodiment of the invention. The locker  10  comprises an enclosure formed by a rigid frame  12  such as of steel or aluminum and preferably comprising angle members  14 ,  16 ,  18 ,  20 ,  22  and  24  as shown, with an access opening at the front of the enclosure. Additional structural members, particularly to rigidify and reinforce walls and roof of the structure, may be included at  26  (diagonal),  28  and  30 . The member  30  preferably is in a V-shape or channel shape, to receive and guide the tires  32 ,  34  of a bicycle  36  schematically indicated as stored within the locker unit  10 . The tire guide channel  34  helps guide the rear tire into a narrow rear portion of the preferably triangular-shaped enclosure, as well as holding the front wheel  34  in alignment while the bicycle is loaded.  
         [0046]    The enclosure has a door  40  which is hinged at one side as shown, and with a handle  42  at an opposite edge of the door, for lifting when the lock has been successfully accessed. An electronic lock  44  preferably is positioned on the frame  46  around the door, the frame being comprised of members  20  and  24 .  
         [0047]    In FIG. 1 no infill is shown on the frame, and this infill may comprise a steel mesh, a strong plastic or fiber-reinforced mesh, sheets of rigid plastic or other appropriate secure material, preferably material which permits visibility into the unit. In one preferred embodiment, the door and at least one of the two sides of the unit have a transparent or translucent material as infill, allowing visibility into the unit for purposes of security and preventing undesired uses of the enclosure. More preferably, both sides, the door and the top all have this visibility-permitting material, allowing plenty of light into the unit.  
         [0048]    An interior security chain  48  may be included, to enable a user of the locker to secure a lock to the bicycle frame for additional security.  
         [0049]    [0049]FIG. 2 shows a preferred embodiment of the locker in a top plan view. This view shows a secure wire mesh  50  used as the infill on the frame  12 , preferably welded to the frame, but alternatively connected by secure bolts or other fasteners inaccessible from the outside of the storage unit  10 . In FIG. 2 the bicycle  36  is seen to be visible from above, as is preferred, and the bicycle is aligned and neatly arranged within the storage unit, due primarily to the wheel guide  30  in which the tires reside. As shown, the bicycle&#39;s handlebars  52  may reach nearly to the side walls.  
         [0050]    [0050]FIGS. 3, 3A and  4 - 9  show details of a preferred form of latch mechanism for the storage unit, an important feature of the invention, as well as other constructional details. In FIG. 9 one manner of securing the infill mesh  50  to the frame is shown, with the hinged-side vertical frame member  20  shown in this particular view. The mesh (or other infill material) can be secured to the frame member  20  by a series of machine screws  54  with nuts  56 , connecting to a metal margin piece  57  secured to the edge of the mesh preferably by welding. The machine screws, which may be {fraction (3/16)}″ diameter stainless flat head countersunk machine screws, preferably have a secure head which is blank or requires a special tool to be engaged, or the nut  56  can be fixed to the screw threads sufficiently that the rotation of the screw head will simply rotate the nut and bolt together, preventing unauthorized disassembly. Alternatively, the mesh may be secured by welding or other secure mechanical means.  
         [0051]    [0051]FIG. 9 also shows the door hinge  58 , which preferably is a continuous hinge down the height of the door, heavy enough to be secure. The hinge  58  is attached as a butt hinge (as by welding or secure bolts or rivets) to the structural frame member  20  and to an edge channel  60  of the door, as shown. The door has similar infill material  50  to the walls and roof in the preferred embodiment.  
         [0052]    [0052]FIG. 4 shows a portion of the front of the unit, at the upper left, revealing that in the preferred embodiment the door edge  40  fits flushly within the unit&#39;s front frame  46 , for a clean appearance and for security against tampering. The lock for the door is shown generally at  44 , and specifically a front plate  44   a  is seen in this figure. This may be an electronic lock with a contact pad  64  for touch-controlled access. Thus, an iButton or touch memory cell is used to access the lock, by contacting the iButton against the touch pad  64 . In an alternative embodiment, the lock can have a keypad, such as an alphanumeric keypad, instead of being activated by touch memory. A mechanical lock could be used if desired. A multi-color LED  66  is shown for displaying colors as discussed above for an electronic lock, or this can be an LED with different flashing modes, indicating modes of operation to the user and to officials. The electronic lock unit  44  preferably also has external contacts  68  as discussed above, for “jumping” the lock with an external battery, such as a 9-volt battery, in the event power is out. This does not access the lock, but merely provides power so that the lock can be accessed with the appropriate iButton, or keypad entry.  
         [0053]    The locker door handle is shown at  42 , including a stationary portion  72  and, in the preferred embodiment, an upwardly slidable upper portion  74 , which is slidable within the sleeve-shaped fixed portion  72 . The sleeve configuration protects the movable handle from being pried or forced.  
         [0054]    The door handle  42  is also seen in FIG. 3 and FIG. 5, and these should be viewed together in understanding the mechanism. FIG. 3 shows in elevational profile the door  40  as surrounded by the frame  46 . The door includes, fixed to the door, at least one latch hook  76 , and preferably three such latch hooks, as shown. These latch hooks, as better seen in FIG. 5, include a sloped back, forward end or ramp  78 , adjacent to which is a notch  80  at the back edge of the sloped end, for receipt of a latch  82  which is inside the door frame. The latch  82  is connected to, or at least engaged by, a vertically-slidable latch bar or latch attachment  84  which extends at least most of the height of the door as shown. The latch bar  84  can extend to the bottom of the door frame as shown, and at its upper end it is normally blocked from upward movement by a retractable bolt  86  of the lock  42 . When the bolt extends out, it blocks the lifting of the latch bar, by abutting directly against the upper end  88  of the latch bar or by entry of the bolt  86  into a notch or hole in the latch bar.  
         [0055]    Since it is desirable that the accessing of the lock only retracts the lock bolt  86  to the release mode momentarily, e.g. for a few seconds, it is preferable that the closure of the door be effective to latch the door in locked position automatically, without any further manual input and without requiring lifting of the latch bar, which is by this time locked to the down position shown. Therefore, the latch  82 , which is cammed upwardly by the latch hook surface  78  as the door closes and then falls back into the latch hook notch  80  under the influence of a latch spring  90  (or by gravity, with a heavier latch member  82 ), is permitted movement independent of the latch bar  84 . The latch member  82  is shown as an oval or racetrack-shaped chain link in the drawings, but it can take other appropriate configurations such as a horizontal bar contained within a slot in the latch bar and urged downwardly either by the tension spring  90  or by gravity. The latch member  82  is restricted as to downward movement by engagement with the latch bar, which lifts the latch member upwardly (to the extent of escaping the locking notch  80 ) as the latch bar is lifted. This restriction can be by any appropriate seat on the latch bar for engaging the latch member, or any appropriate projection of the latch bar which engages the latch member in one direction, preventing down movement of the latch member relative to the latch bar. FIG. 6 shows the latch member  82  as contained within a fold or pocket of the latch bar  84 , which preferably is S-shaped in cross section as shown. The latch member  82  is nested within the latch bar and can be supported against downward movement in the latch bar by an appropriate form of ledge or projection below the latch member. FIG. 6 also shows the latch hook  76  fixed (as by welding) to the door edge  40   a  through the frame member or jamb  20 , into the interior of the frame and through the latch bar  84 , intercepting and engaging with the latch member  82 . FIG. 6 also shows in dashed lines a vertically oriented latch bar restraint  92  that retains the vertically slidable latch bar within a pocket  94  of the frame.  
         [0056]    The door handle  42  operates in a manner which provides for maximum security. Instead of being located on or inside the door, as is typical, the vertically slidable latch bar  84  is secured within the door jamb or frame member  20  as explained above. The handle  42  needs to be capable of engaging and lifting this latch bar, but only for initially releasing the latch hooks  76  from the latch members  82 . Once the door is free of the latch, the latch bar can be returned to its normal, down position. For this purpose, the movable part  74  of the handle  42  is fixed to a latch bar lifter or latch bar shifter  96  which extends into the frame and into holes  98  in the latch bar itself, as seen particularly in FIGS. 5 and 8. The frame member  20  has a vertically elongated slot  100  through which the latch bar lifter  96  passes, allowing it free up-and-down movement relative to the frame.  
         [0057]    Thus, when the lock  44  is successfully accessed, causing the lock bolt  86  to retract to the release mode, at that instant the user is permitted to pull upwardly on the upper, release portion  74  of the handle and thus to lift the latch bar shifter  96 . This lifts the latch bar, which in turn lifts the latch member  82  as explained above. Thus, with the handle portion  74  held upwardly for a second or even a fraction of a second, the user pulls the door open, clearing the latch hook  76  from the latch  82 . As this is accomplished, the latch bar lifter  96  pulls away from the latch bar  84  allowing the latch bar to drop back to its down position. All this takes places within a few seconds, or even less than a second, and the lock bolt  86  extends back outwardly to its locked position, preferably by spring force or timed delay (as with a double-acting solenoid). Thus, the actual retraction of the lock bolt can be for only about one second, or it can be two to four seconds to assure that the user has plenty of time to open the door. Once the latch bar is lifted, even if the lock bolt tries to re-extend (by spring force) it will merely be delayed until the latch bar drops.  
         [0058]    After the door is opened, the latch mechanism is essentially locked. The latch bar shifter is preferably short enough that the latch bar drops back to normal position even before the door edge is fully clear of the frame, preventing insertion of a tool to hold the bar in the up position.  
         [0059]    Closing of the door will effect the upward camming of the latch member by the latch hook ramp  78  to relatch the door in the closed, locked position.  
         [0060]    [0060]FIGS. 5A, 6A,  6 B and  6 C show a modified embodiment of the invention wherein the automatic latching of the door upon closure is accommodated by movement in the latch hook (connected to the door) rather than movement of the latch member (contained within the frame). Here, the latch bar  84   a  has a slotted opening  110  (and the frame has an adjacent opening) through which extends a housing  112  for the latch hook  76   a , which in this case comprises a vertically reciprocable plunger. The plunger and housing assembly are shown in FIG. 6C, indicating that the housing is a folded component, preferably of metal, within which the plunger  76   a  is slidable, biased upwardly by a compression spring  114 . A jamb clip  116  fits within the housing  112  and retains the plunger in the housing, within the limits of its range of motion. This plunger and housing assembly is a locker part sold by Worley, such as available at ROBERTBROOKE.COM, part number 530100.  
         [0061]    The housing as mounted to the door  40  is shown in FIG. 6A. A mounting flange  112   a  is secured to a bracket  118  at the inside of the door, and the folded-over portion  112   b  extends into the frame, as shown. FIG. 6A shows the sloped-back upper end  76   b  of the latch hook or plunger  76   a . The latch bar is indicated at  84   a , in this case preferably a rectangular latch bar having an interior within which the plunger  76   a  and folded-over portion  112   b  of the plunger housing can fit.  
         [0062]    [0062]FIG. 5A shows that the door is latched by positioning of the plunger or latch hook  76   a  at its extended position behind a wall  84   b  of the latch bar. As the door is closed, the sloped-back forward and upper surface  76   b  of the plunger engages the bottom edge of the wall or plate  84   b  of the latch bar, camming the plunger downwardly into the housing, against the force of the compression spring  114 . Once the door is sufficiently closed that the plunger clears the latch bar wall  84   b , the plunger springs upwardly to its normal and extended position, latching the door closed. When access is granted via the lock, with retraction of the lock bolt  86 , however, the latch bar is permitted upward movement by the user&#39;s pulling upwardly on the handle  74 . The latch bar opening  110  has sufficient space below the plunger housing  112  to allow the latch bar to be lifted such that the plate or wall  84   b  is clear of the extended plunger  76   a , i.e. the opening  110  has been shifted to clear the plunger for opening of the door.  
         [0063]    [0063]FIGS. 5A and 6B also show a rod  120  which is included in a preferred embodiment, fixed to the frame and supporting the latch bar for vertical sliding movement. FIG. 5A shows a groove  122 , formed in parallel at both sides of the latch bar, which travels over the rod  120 . The groove is shown with a J-shaped lower end  124  for initial assembly into the frame.  
         [0064]    [0064]FIG. 7 is a top plan sectional view at the lock  44 . This view shows some aspects of security of the system, in which access to the lock  44  is not permitted the user even from the inside of the enclosure, when the door is open. The lock, if electronic, may be in two components: the front plate  44   a  seen in FIG. 4, and the lock mechanism  44   b  with retractable bolt  86  as seen in FIG. 7. A security plate  102  is connected into the frame member  20  and preferably locked in place, as by keyed cam locks at appropriate locations on the inside of the frame. This security plate may extend the full height of the frame member  20  if desired, or it can be in separate sections. In any event, as seen in FIG. 3, this plate also protects the frame  46  from being accessed at the locations of the latch members  82 , which may be at three different locations in the frame as shown in FIG. 3. FIG. 3 indicates two different locks  104  provided to secure the security plate  102  in place. Alternatively, secure fasteners requiring a special tool could be used.  
         [0065]    [0065]FIG. 7 also indicates an electrical cable  106  extending from the rear lock component  44   b . This connects to the front lock plate  44   a , not seen in FIG. 7. An additional cable (not shown) can extend from the lock for providing audit and current status information for all units, since the electronic lock preferably has microcontroller and memory, recording access events. Power wires may also be desired. The invention makes this wiring possible in a secure way, since the electronic lock is located in the fixed frame rather than in the door, where a cable would have to pass from the frame to the door, most likely exposing the cable to tampering or vandalism.  
         [0066]    The invention allows opening of the door with one hand after the lock is released. Although the accessing handle could be on the frame instead of the door, this would require two hands to open the door.  
         [0067]    The invention is described with a vertically slidabie latch bar that falls by gravity to its normal, locking position, but the normal position could alternatively be an upper position, biased by a spring. The latch hooks, latch members, latch bar shifter, lock, etc. would still function similarly except in requiring a down motion to shift the latch bar permitting the door to open.  
         [0068]    Although the invention is described above in its preferred embodiment with a vertically slidable latch bar, parallel to a vertical-axis hinge arrangement for the door, the important principles of the invention also apply to other arrangements. For example, the hinge could be on a horizontal axis for some applications such as where space or convenience require this, and the latch bar could be a horizontally slidable latch, thus being parallel to the hinge axis, biased to a normal, locked position by a spring and movable against the spring when the lock is in release mode; references herein and in the claims to lifting, up, down, above, below, etc. are not to be taken as limiting in this regard but only as indicating relative positions and movements. Still further, instead of an elongated latch bar this element could simply comprise a movable latch element, which could be shorter and still slidable, or which could be a rotatable latch element. In any event, the latch element is contained securely within the door frame and preferably it is not movable to its release position except when the lock is in release mode and the door is closed, putting in operative position a latch element mover or shifter which could be a rotational component extending into the frame from the door, rather than a slidable latch element shifter as disclosed above, co-acting with a slidable latch element. With the lock, movable latch element and latch member or members contained within the frame and inaccessible to vandals or to the user even when the door is open, the latch mechanism of the invention in any of the above forms provides distinct advantages and heightened security in a mechanism which is still relatively simple in construction.  
         [0069]    An alternative embodiment of the invention still includes the two locked modes—available locked and unavailable locked—but eliminates the latch mechanism. In such form the lockers have electronic locks that are always in locked mode when the doors are closed. This can be with electrically retractable spring latches or electrically movable bolts that sense door closure and extend upon closure. Multiple bolt or latch points can be included. Generally, in a battery-powered system for large lockers such as bicycle lockers, the mechanical latch (controlled by electronic lock) is preferred, so that the user moves relatively heavy latch components and only a lightweight bolt is moved electrically.  
         [0070]    The above described preferred embodiments are intended to illustrate the principles of the invention, but not to limit its scope. Other embodiments and variations to this preferred embodiment will be apparent to those skilled in the art and may be made without departing from the spirit and scope of the invention as defined in the following claims.