Abstract:
A cam lock for cabinets, drawers, drug cabinets, credenzas, sliding doors, lockers, mail boxes and other door type applications is compact in size, fits an existing cam lock opening and provides electronic access via a keypad or other electronic access. Using batteries, such as AAA size batteries or smaller, the lock has electronics that release a lock turn knob or handle when the correct code is entered. Preferably a set of electronic contacts is included at an accessible position on the lock housing to allow both master access and power jumping with a common manager&#39;s implement, for situations of lost codes and/or battery failure. In a particular embodiment the lock is long, narrow and low in profile so as to fit on the margin of a steel or wood file cabinet, compatible with the cam lock opening already provided. The locks, NFC-enabled, can be used in securing delivery boxes to enable delivery access, when authorized.

Description:
[0001]    This application is a division of application Ser. No. 14/252,503, filed Apr. 14, 2014, now ______, which was a continuation-in-part of application Ser. No. 13/945,695, filed Jul. 18, 2013, which was a continuation-in-part of two prior applications: Ser. No. 11/809,172, filed May 30, 2007, now U.S. Pat. No. 8,495,898, and Ser. No. 12/214,357, filed Jun. 17, 2008, now U.S. Pat. No. 8,490,443. Ser. No. 13/945,695 fully incorporated by reference all of the content of U.S. Pat. Nos. 8,495,898 and 8,490,443, which content is repeated and incorporated here. All content of application Ser. No. 13/945,695 is incorporated by reference here. Application Ser. No. 11/809,172 claimed benefit from provisional application No. 60/810,195, filed May 31, 2006. 
     
    
     BACKGROUND OF THE INVENTION 
       [0002]    This invention concerns locks for cabinets, lockers, drawers, access panels and similar situations. Specifically the invention embraces an electronic cam lock that fits standard cam lock openings. 
         [0003]    Metal and wood file cabinets, desk and cabinet drawers, locker doors, access panels and doors, mail boxes, dispensers and other secure situations often utilize relatively simple lock mechanisms known as cam locks. Such cam locks may or may not involve a camming action. In some cases they move other mechanisms that are engaged with the door or drawer of the cabinet or engaged with other mechanisms that are linked to the door and drawer of the cabinet or multiple doors or drawers of the cabinet. In one of the simplest forms, a cam lock on a cabinet door typically fits in a ¾ inch diameter D-shaped or double D-shaped hole and, at the back side of the cam lock cylinder unit, has a metal blade or arm called a cam that rotates when the key is turned, from a position disengaged from surrounding cabinet hardware to a position of engagement in a slot or behind a ledge of the surrounding cabinet hardware. Other locks, such as those for desk drawers, commonly referred as cabinet locks, involve a camming type action as the key and plug are rotated. The rotation causes a cam or nipple to move a deadbolt linearly to a locking or unlocking position or in the case of a spring loaded latch or deadlatch the rotation causes the cam or nipple to move a latch or deadlatch to unlocking position and removing the key keeps the latch or deadlatch in the extended locked position. 
         [0004]    Metal filing cabinets often utilize cam locks, or a variation known as a plunger type lock in which a spring loaded plunger/lock cylinder located in the top horizontal margin of the cabinet, when pushed in, will lock all drawers. The use of a key releases the spring plunger to return to the outward position and unlock the drawers. 
         [0005]    Locker and cabinet locks have included electronic locking devices, some of which utilized keypads and some of which utilized IButtons or other ID or non-volatile memory devices which work on contact to release the lock. See, for example, U.S. Pat. Nos. 5,894,277, 5,886,644, 6,655,180 and 6,791,450. The disclosures of all of these patents are incorporated herein by reference. 
         [0006]    There is a need for a relatively simple, easily used, reliable and compact electronic lock, preferably a keypad lock but optionally operable by an electronic key, or both, for situations in which typically cam, plunger and cabinet locks were employed, and capable of fitting in a standard opening or bore of a standard cam, plunger or cabinet lock cylinder in a cabinet, door, access panel, mail box, dispenser, etc. and alternatively capable of fitting in a standard shell of a standard cam, plunger or cabinet lock cylinder in a cabinet, door, access panel, mail box, dispenser, etc. This is an objective of the current invention described below. 
       SUMMARY OF THE INVENTION 
       [0007]    The invention addresses these needs with a low profile and very compact electronic lock that, in one application, fits in the top one inch horizontal margin of a steel file cabinet (or a side vertical margin). The compact electronic locking device in one embodiment has a knob or handle that can rotate the cam lock cylinder plug when such manual rotation is permitted by the lock electronics. A keypad for entry of a code may be included, and if so, the code in preferred embodiments can be either permanently set to a reprogrammable code, or set in each case by a temporary user, who can then input the same code to lock and unlock the lock, this feature depending on circumstances and function desired. 
         [0008]    In one preferred embodiment particularly adapted for a file cabinet, the locking device is less than one inch in height, about two inches in length for one form, about three to five inches for another form, and about ⅜ to ¾ inch in depth or more preferably no more than about ⅝ inch or less in depth, as to the housing of the device. A cam locking device of this size will fit unobtrusively on the surface of the horizontal top margin area of a steel file cabinet. The housing may contain several small battery cells, such as two AAA batteries, but preferably smaller batteries such as coin cell or button-type batteries for further reduction of housing size. From the back of the housing in one embodiment extends the cam lock cylinder unit of conventional cam lock size, and with a length to fit the application, i.e. the depth of material and configuration where mounted. The rear-extending cylinder unit may have an external thread, so that a nut or threaded ring is tightened down to firmly retain the cylinder and housing in place. In other embodiments a dummy plug can extend back from the housing unit, or simply a driver or spindle. Since the cam lock opening in the cabinet or door or panel will typically be the conventional D-shaped opening or double D-shaped opening, the housing is fixed in place against rotation by this configuration. However, another fastening location(s) may be included, such as a machine screw assembled from the back and through a hole in the drawer or panel, engaging in a threaded hole provided in the housing, or screw posts extending from the back of the housing. This threaded hole or screw post preferably is at an opposite end of the housing from the location of the cylinder and turning knob or handle. There may be more than one threaded hole or screw post depending on the mounting preferences. In an alternative configuration, the housing back can simply have a nipple that extends in a hole formed in the cabinet, drawer or door, or a hook-shaped element that extends from the back of the housing and engages firmly in the hole, particularly for relatively thin metal cabinets. 
         [0009]    It is an important feature of the invention that the electronic cam lock device be compact and relatively simple, at least as to mechanical elements, and without any further electronics or housing required at the back side of the door or panel. Essentially the only element at the back side of the door, drawer or panel is the rear-extending cam lock cylinder unit itself, with attached cam positioned to engage with a ledge or slot or other hardware to retain the door(s) or panel locked. In some embodiments the rear-extending element is a dummy plug or driver. An alternative form of the lock still comprises a single housing but is positioned at the back side of the panel, drawer, etc., in a through-the-panel mounting with only the knob or handle and the access terminal or keypad extending through the panel. 
         [0010]    In one preferred form, the invention is embodied in a cam lock for a door, cabinet or drawer and includes a compact housing containing electronics and having a keypad or other terminal enabling entry of codes by a user, a cam cylinder unit or driver extending from a back side of the housing, in a standard cam lock size adapted to fit through a standard cam lock opening in a cabinet or door for extending therethrough, and with a knob or handle on the housing for operating the cam lock manually when permitted by the electronics. A battery compartment in the housing, accessible from the front of the cabinet, contains one or more battery cells for operating the electronics. 
         [0011]    In another preferred form, the invention is embodied in a cam lock for a door, cabinet or drawer and includes a compact housing containing electronics and having a keypad or other terminal enabling entry of codes by a user, a plug of the cam, plunger or cabinet lock cylinder unit extending from a back side of the housing that matches the size and shape of the cam lock shell already mounted on the door, cabinet or drawer, and with a knob or handle on the housing for operating the cam lock manually when permitted by the electronics. Again, a battery compartment in the housing, accessible from the front of the cabinet, contains one or more battery cells for operating the electronics. 
         [0012]    In another preferred form, the invention is embodied in a cam lock for a door, cabinet or drawer and includes a compact housing containing electronics and having a keypad or other terminal enabling entry of codes by a user, a special shaped driver unit extending from a back side of the housing that matches an opening on the plug of the cam cabinet or drawer, a lock shell already mounted on the door, and with a knob or handle on the housing for operating the cam lock manually when permitted by the electronics. Again, a battery compartment in the housing, accessible from the front of the cabinet, contains one or more battery cells for operating the electronics. 
         [0013]    In another preferred form, the invention is embodied in a cam lock for a door, cabinet or drawer mountable from back of the door, cabinet or drawer such that only the user interface extends through the face of the door, cabinet or drawer and includes a compact housing containing electronics and having an electronic key receptacle and in some cases, a keypad for entry of codes by a user, a specially shaped driver unit extending from a back side of the housing that matches the end of a cam lock or cam lock plug of the typical mechanical lock for engaging with a strike or other locking bars, cams or apparatus, and with a knob or handle on the housing for operating the cam lock manually when permitted by the electronics. A battery compartment in the housing, accessible from the back of the lock, contains one or more battery cells for operating the electronics. 
         [0014]    In another preferred form, the invention is embodied in a cam lock for a door, cabinet or drawer mountable from back of the door, cabinet or drawer such that only the user interface extends through the face of the door, cabinet or drawer and includes a compact housing containing electronics and having an electronic key receptacle and an RF reader or wireless reader or IButton reader for entry of a code by a user, a specially shaped driver unit extending from a back side of the housing that matches the end of a cam lock or cam lock plug of the typical mechanical lock for engaging with a strike or other locking bars, cams or apparatus, and with a knob or handle on the housing for operating the cam lock manually when permitted by the electronics. 
         [0015]    In another preferred form the lock devices are fitted with an RJ45 jack or wireless antenna for network connectivity and external power. The locks may be fitted for NFC communication. 
         [0016]    It is therefore among the objects of the invention to improve over prior cam and cabinet locks, with an electronic cam lock that can be retrofitted to existing cam lock and cabinet lock openings in doors, drawers, access panels, mail boxes, dispensers, and other furniture that provides access and no egress without a mechanical key, as well as to provide an improved locking solution for new applications wherein the internal locking systems for locking multiple points are configured to receive a cam, plunger or cabinet lock. The device is relatively simple, compact and unobtrusive. These and other objects, advantages and features of the invention will be apparent from the following description of preferred embodiments, considered along with the accompanying drawings. 
     
    
     
       DESCRIPTION OF THE DRAWINGS 
         [0017]      FIG. 1  is a perspective view showing an electronic cam lock device of the invention. 
           [0018]      FIG. 1A  is a schematic view showing a feature internal to the cam lock. 
           [0019]      FIG. 2  is a view showing the device on a metal file cabinet. 
           [0020]      FIG. 3  is an elevation view showing the front of the device. 
           [0021]      FIG. 4  is a sectional plan view showing the electronic cam lock device as installed, in one preferred manner of installation, on a cabinet or door. 
           [0022]      FIG. 4A  is a sectional view showing a variation of what is shown in  FIG. 4 . 
           [0023]      FIG. 5  is a view similar to  FIG. 4 , but showing the device in a locked position for a drawer, panel or door. 
           [0024]      FIGS. 6 and 6A  show a typical cam lock shell mounted on a door with its plug being inserted. 
           [0025]      FIGS. 7 and 7A  show the same configuration shown in  FIGS. 6-6A  replaced by the plug of the current invention. 
           [0026]      FIGS. 8, 8A and 8B  are perspective views showing replacement of an existing key operated cam lock cylinder plug with the current invention. 
           [0027]      FIG. 9  is a perspective view showing the current invention with matching plug being applied to a cabinet lock with a bolt. 
           [0028]      FIG. 10  is a perspective view showing the current invention with matching plug being applied to a cabinet lock with a spring loaded latch or deadlatch. 
           [0029]      FIG. 11  shows a side view of what is shown in  FIG. 9  being installed on a door or drawer. 
           [0030]      FIG. 12  shows a side view of what is shown in  FIG. 10  being installed on a door or drawer. 
           [0031]      FIG. 13  shows a perspective view of an electronic cam, cabinet or plunger lock of the invention with special shaped driver extending from the rear of the device. 
           [0032]      FIG. 14  shows a perspective view of the current invention with a specially shaped driver being applied to a cam lock with matching plug. 
           [0033]      FIG. 15  shows a perspective view of the current invention with a specially shaped driver being applied to a cabinet lock with bolt with matching plug. 
           [0034]      FIG. 16  shows a perspective view of the current invention with a specially shaped driver being applied to a cabinet lock with latch or deadlatch. 
           [0035]      FIG. 17  shows a perspective view of the current invention with a specially shaped driver being applied to an oval shaped plunger lock with matching plug. 
           [0036]      FIG. 18  shows a perspective view of the current invention with a specially shaped driver being applied to a round shaped plunger lock with matching plug. 
           [0037]      FIG. 19  shows a perspective view of the current invention with a specially shaped driver being applied to a switch lock with matching plug. 
           [0038]      FIG. 20  shows a perspective view of the current invention with a specially shaped driver being applied to a screw type T handle lock with matching plug. 
           [0039]      FIG. 21  shows a perspective view of the current invention with a specially shaped driver being applied to a cam type T handle lock with matching plug. 
           [0040]      FIG. 22  shows a perspective view of the current invention with a built in flange allowing recess mounting. 
           [0041]      FIG. 22A  shows a variation of  FIG. 22  in which a lever replaces a knob, a variation applicable to all embodiments. 
           [0042]      FIG. 23  shows a typical prior art mechanical key-operated cam lock. 
           [0043]      FIG. 24  shows a typical prior art oval shaped plunger lock. 
           [0044]      FIG. 25  shows a typical prior art round shaped plunger lock. 
           [0045]      FIG. 26  shows a typical prior art cabinet lock with bolt. 
           [0046]      FIG. 27  shows a typical prior art cabinet lock with spring loaded latch or deadlatch. 
           [0047]      FIG. 28  shows a typical prior art switch lock. 
           [0048]      FIG. 29  shows a typical prior art T handle screw type lock. 
           [0049]      FIG. 30  shows a typical prior art T handle cam type lock. 
           [0050]      FIG. 31  is a perspective view showing an electronic cam type lock of the invention, for a cam lock and similar functions, with a receptacle for electronic input and without a keypad. 
           [0051]      FIGS. 32 and 33  are sectional plan and elevation views showing the lock device of  FIG. 31 . 
           [0052]      FIGS. 34A and 34B  are partially sectioned side elevation views showing a modified lock device as fitted into an existing cam lock or similar situation. 
           [0053]      FIGS. 35A, 35B and 35C  are perspective views showing a drawer or door panel having provision (a hole) for a cam lock or cabinet lock, an embodiment of a cam lock of the invention, and the cam lock as installed in the panel. 
           [0054]      FIG. 36  is a perspective view, exploded, showing a lock device of the invention and indicating its installation into a modified cylinder device of a cam lock or cabinet lock. 
           [0055]      FIG. 37  is a view somewhat similar to  FIG. 36 , but showing the device being fitted with a pin/tumbler cylinder of a cabinet lock and with a spring latch. 
           [0056]      FIG. 38  is a perspective view showing a modified lock device of the invention with provision for recessed mounting. 
           [0057]      FIGS. 39A to 39C  are perspective and cross section views showing a through-panel mounting for an electronic lock of the invention. 
           [0058]      FIGS. 40A to 40C  are perspective and cross section views similar to  FIG. 39A-39C , showing a modified lock with a keypad. 
           [0059]      FIG. 40D  shows an alternative battery arrangement. 
           [0060]      FIG. 41  is a perspective view showing a lock device of the invention with a key reader and an IButton reader. 
           [0061]      FIG. 42  is a perspective view showing a lock device of the invention with a key reader and a wireless reader. 
           [0062]      FIG. 43  is the same lock device shown in  FIG. 41  but configured for mounting through the panel of a door, cabinet or drawer. 
           [0063]      FIG. 44  is the same lock device shown in  FIG. 42  but configured for mounting through the panel of a door, cabinet or drawer. 
           [0064]      FIG. 45  is the same lock device shown in  FIG. 40A  but with the addition of a network antenna, network jack receptacle and external power port. 
           [0065]      FIG. 46  is the same lock device shown in  FIG. 39A  but with the addition of a network antenna, network jack receptacle and external power port. 
           [0066]      FIG. 47  is the same lock device shown in  FIG. 43  but with the addition of a network antenna, network jack receptacle and external power port. 
           [0067]      FIG. 48  is the same lock device shown in  FIG. 44  but with the addition of a network antenna, network jack receptacle and external power port. 
       
    
    
     DESCRIPTION OF PREFERRED EMBODIMENTS 
       [0068]      FIG. 1  shows an electronic cam lock  10 , in a preferred form of a keypad cam lock, with a rotatable knob or handle  12  extending from a housing  14 . A keypad  15  is exposed at the front of the housing to allow entry of a code, using the usual numerical digits 1 to 0 and/or letters of the alphabet, as illustrated. The keypad preferably includes a “clear” button  16  and an “enter” button  18 , the latter shown with a key symbol in the drawing. The lock can be programmed such that the enter button is pushed as the last button in all code entries, thus enabling different numbers of digits for different purposes, as well as some other functions. However, the lock can be programmed otherwise if desired, such as being programmed to operate after a designated number of valid key strokes. A status LED is included at  20 ; this can show locked/unlocked states as well as battery status. 
         [0069]    At  22  is shown a recess or connection with a plurality of electrical contacts, preferably three as shown. This can be for several purposes, including providing “jump” power in the event of battery failure, and use of an electronic master key for entry of a master code by contact with this connection, when a key code to which the device is set has been forgotten or lost. As in U.S. Pat. No. 7,336,150, which is incorporated herein by reference, this set of contacts  22  can be connected to receive both jump power and a master code simultaneously (or either one, or both separately). 
         [0070]    Batteries are contained within the housing  14 . In the embodiment shown, a slide door  24  connects with the housing to close a battery compartment which may be, for example, for two AAA battery cells. The slide door  24  may be locked against sliding whenever the cam lock device is in the locked configuration, such as by a slide pin driven by turning of the cylinder plug. This prevents unauthorized removal of batteries or tampering with the interior of the electronic lock. The door  24  may be hinged rather than slidable, or secured by a screw, which can be a security screw. The unauthorized opening may also be prevented by incorporating a single or multi-point press-to-release lock that requires a special tool for opening the battery compartment. 
         [0071]    In  FIG. 1  the lock device  10  is shown as secured on a surface or panel  25 . The word “panel” is sometimes used herein and in the claims to refer to the component or surface to which the lock is secured, whether the panel is a drawer front, or margin area above, below or to the side of the drawer front, a cabinet door or margin, an access panel or adjacent structure, etc. 
         [0072]      FIG. 3  is a frontal view of the lock device, and  FIGS. 4 and 5  show that the handle or knob  12  connects directly with a cam lock cylinder unit  26 , and specifically the handle  12  turns with a movable member, e.g. rotatable bolt or core  28  which rotates within the fixed cylinder unit  26  when permitted by the electronics.  FIG. 5  is a side view of the lock device, generally as seen from the right side of  FIG. 1  or  FIG. 3  and showing one example of latching. Note that the cylinder unit&#39;s bolt or core  28  can be extended as needed, such as for a wood drawer, panel, etc. 
         [0073]      FIG. 23  shows a typical, simple prior art cam lock  29 , of a type which can be replaced by the electronic cam lock unit  10 . 
         [0074]    The rotatable plug  28  of the cam lock cylinder unit  26  ( FIGS. 3-5 ) is shown fixed to a metal arm or cam  30  as this actuator is typically called. The cam is secured on the plug or rotatable member  28  via a flat  32  on the rotatable plug number and a corresponding hole in the cam (hole not shown), so that the cam is fixed against relative rotation on the plug. Further, the end of the plug is threaded and a nut  34  is tightened down for retention. 
         [0075]      FIG. 5  shows the cam  30 , which can be in a bent offset shape as shown or can be any other desired configuration (a multiplicity of different cam shapes are available), engaged in a slot  36  in a structure  38  adjacent to a panel  40  to which the cam lock device is secured, via a nut or threaded ring  42 . A flat  43  on the cylinder  26  matches the D configuration, or two opposed such flats can be included. Thus, the panel  40  may be a drawer to be pulled outwardly from the structure  38  when the lock is unlocked, or a door or cabinet or access panel. Similarly the lock device  10  can be installed in a panel of a fixed structure, such as the two locks shown as secured to the top margin areas of  44  and  46  in two adjacent banks of file drawers or file cabinets  48  and  50  in  FIG. 2 . In that case a cam can engage downwardly against a ledge or into a slot in the adjacent file drawer  52  or  54  when locked, preventing the pulling out of a drawer, or a more complex mechanical arrangement can be included, typical of such lateral file cabinets, whereby the lock either holds a locking mechanism in place for both drawers, or the locking of the top drawer effects the locking of the lower drawer as well, through a well-known form of mechanical interlinkage. 
         [0076]    In a simple cam lock arrangement such as shown in  FIGS. 3, 4 and 5 , and referring to the simplified schematic view of  FIG. 1A , the electronics (not shown but indicated at E in  FIG. 1A ) within the lock housing  14  can include or be connected to a slidable pin  55  driven by an electrically operated device, i.e. a solenoid or miniature motor M, for engaging the pin with a notch  55   a  in the internal rotatable member  55   b  leading from the handle or knob  12  to the rear-extending bolt  32 , to prevent rotation. The pin may be urged toward the notch by a spring  55   c . The electronics can be similar to those disclosed in any of the above patents incorporated herein by reference. PIN code actuated electronics are well known to those skilled in the art, and, when an appropriate code is entered using the keypad, the electronics will connect power to the motor or solenoid, or other electronic device to momentarily retract the blocking pin from such a notch in the rotatable member. If a solenoid is used it is biased to be normally urged into engagement with the notch whenever the notch is located in the appropriate position. If desired the lock can be set up to simply leave the notch out of contact with the biased pin when the knob has been rotated to unlock the cam lock device. The drawer or door or panel can thus be left with the lock in this state during working hours or during any period desired, until the user wishes to secure the drawer or door again. At that point, the user rotates the knob or handle until a “click” is felt, when the pin has re-engaged in the notch to lock the knob against further turning. A motor can also operate the pin with spring linkage. 
         [0077]    An alternative arrangement is to have the cam lock cylinder unit define two different positions in which its movement is blocked. In this case, two notches (not shown, but second notch similar to  55   a  in  FIG. 1A  but at different rotational position) are provided in the internal rotatable member, one for locking the door or drawer and one for holding the knob and cam in a fully unlocked position, and in this situation a code must be entered in order to return the lock to the locked position. 
         [0078]    Although the cam lock device  10  can be securely retained on a door front panel or metal file cabinet panel or other door, drawer or access panel using the threaded cam lock cylinder unit  26  with the tightened nut  42  and the registry provided by the D or double D-shaped cam lock cylinder and opening typical of cam locks (see flat  43  shown in  FIGS. 4 and 5 ), the installation may include an attachment at the other end of the lock housing, i.e. the end opposite where the handle or knob  12  is located (left side in  FIG. 3 ). In  FIG. 4  is shown a machine screw  56  that passes through a hole  58  in the panel  40   a , tightened into a threaded opening in the housing  14 . This will require drilling of a small hole, approximately ⅛ inch diameter, through the panel. Alternatively, the back of the housing  14  can simply have a nipple  57  that extends into the hole  58  (as indicated in  FIG. 4A ), or a hooked nipple, generally L-shaped, which is extended such that the leg of the L-shape goes through the hole to the back of the panel, then the housing is pivoted down against the panel until the cam lock cylinder unit  26  passes through the cam lock hole in the cabinet or panel. 
         [0079]    An important feature of the invention is that the keypad-operated electronic cam lock device  10  includes no housing or electronic components at the inside of a door or drawer or panel. The only structure of the lock device extending into the interior or back side of the panel on which attached is the cam lock cylinder unit  26  and, optionally, a threaded fastener or machine bolt  56 . This makes the unit of the invention compatible with situations in which nearly all cam locks are used, since those simple prior art key-operated devices typically comprise a rotatable plug for receiving the mechanical key, a cam lock cylinder shell with a front face plate, and a tail on the plug which has the cam affixed to the tail. Access can be difficult at the inside of a cabinet, and the avoidance of any inner housing or electronics (such as included in the some of the locker locks disclosed in the patents referenced above) is an important feature. 
         [0080]    Although a plunger type lock of the type often included on multiple-drawer file cabinets is not illustrated in the drawings, the invention applies to this type of lock as well. In that case the rotatable handle  12  on the lock unit  10  is replaced with a spring plunger unit with rotatable core, similar to a typical key-operated spring plunger unit such as the unit  60  shown in  FIG. 24 ; the internal mechanism for holding the core against rotation can be similar to that described above, that is, an electrically operated blocking pin will release the rotatable core and handle  12  and upon core rotation the plunger slide blocking device ( 62  in  FIG. 24 ) will be retracted allowing the spring plunger unit to release out by action of a spring thus opening the drawers. The side of the sliding plunger unit can be slotted to allow the electrically operated blocking pin to enter a channel in the side of the rotatable core, to hold the core against rotation when locked. 
         [0081]    As mentioned above, instead of a solenoid operating the blocking pin operating in the lock housing  14 , a miniature motor can be used. Such miniature motors require very small current and can be used to implement the extension or retraction of the pin that blocks the handle  12  or other device from being manipulated. The term electromagnetically operated device includes a solenoid or miniature motor or other appropriate driving electric device. 
         [0082]      FIGS. 6-6A and 7-7A  show a typical cam lock shell mounted on a door, with the plug  70  shown removed in  FIG. 6  and inserted into the shell  72  in  FIG. 6A  to form the cylinder unit; and replacement by an electronic lock  74  with cylinder plug  75 , retrofitted into the shell  72  in accordance with the invention ( FIGS. 7 and 7A ). The plug  75  is a “blank” plug that will operate the lock when installed via a retainer clip or pin  81 , with the electronics to control access. In  FIG. 7  the electronics housing  76  has a recess  78  shown in dashed lines, surrounding the extending plug  75 , for the purpose of accommodating the slightly protruding face  80  of the cylinder shell  72  as installed in the door or drawer  71 . Many of the cam locks used in furniture do have this type of front loaded plug which can also be removed for service and rekeying purposes. 
         [0083]      FIGS. 8, 8A and 8B  show another door or drawer front  82  as fitted with a conventional cam lock or cabinet lock having a cylinder shell  72  such as shown in  FIGS. 6 and 7 .  FIG. 8  shows the prior art lock  72   a  with a key  73  extending into a cam lock plug  84 , while  FIG. 8A  shows the plug removed, revealing only the face plate  80  of the cam lock/cabinet lock cylinder  72 .  FIG. 8B  shows the electronic lock  74  of the invention as installed into the opening defined by the lock cylinder  80  in door or drawer front  82 . The lock  74  preferably has the same operational features as the lock described above with respect to  FIGS. 1-5 , the difference being that the plug  75  ( FIG. 7 ) extends back from this unit, for fitting or retrofitting into an existing cylinder  72  that previously has had a conventional plug and key. 
         [0084]    As is known by those skilled in the art, the prior art current plugs  70 ,  75  can be removed from the cylinder shell  72 . This can be done by access to the spring loaded wafer or retainer clip  81 . Access to this spring loaded retention device is restricted as is well known in the art. 
         [0085]      FIGS. 9-12 , as well as the prior art views of  FIGS. 26  and  27  all relate to another application of the invention.  FIG. 9  shows an electronic lock unit  74  according to the invention in position to be assembled into an existing cabinet lock  86  of conventional design, the cabinet lock including an extendable/retractable bolt  88  which extends or retracts in response to, in the case of the prior art as shown in  FIG. 26 , rotation of a cylinder plug  90  that is positioned for rotation in the cabinet lock cylinder shell  92 , and accessed by a key  94 . The cylinder shell  92  extends through a door, drawer or other wall  96  as shown in the side elevation view of  FIG. 11 . Thus, in this type of lock there is no protruding face plate on the cylinder shell; the unit  86  is secured from the back, preferably via screws. 
         [0086]    The exploded view of  FIG. 9  shows that the unit  74  of the invention is simply inserted into the lock&#39;s plug opening  98 , such that the plug  75  of the new unit goes into the hole  98  and refits the lock  86  just as the keyed plug was fit therein. Again, a spring loaded secure retainer  81  is included so that access is restricted. The retention of the plug can be achieved by another type of clip or retainer ring as well. 
         [0087]      FIGS. 10, 12 and 27  show a slightly different type of unit  86   a  wherein the locking device is a spring or dead latch  100  rather than a bolt such as shown in  FIG. 9 . The rest of the apparatus, including the unit  74  of the invention and the manner in which it is fitted into the lock to replace a keyed plug from the prior art, are the same. 
         [0088]      FIGS. 13 through 21  show modified embodiments of the invention, particularly addressing situations in which an electronic lock of the invention will require components assembled from both inside and outside of a door, drawer, etc., as in the case of a cabinet lock, for example, as well as providing for a universal front electronic unit. The devices described with reference to  FIGS. 9 through 12  are examples of two-part systems but they are principally for retrofit situations where in a “blank” plug extending from the electronic access device  74  of the invention is fitted into a cabinet lock type cylinder shell which is without a plug. In the variations shown in  FIGS. 13 through 21 , which should be viewed along with corresponding prior art views of  FIGS. 23-30 , the outside and inside components are connected together simply by a driver or extension of keyed shape, such as square, splined, D-shaped, flat, etc., since no plug or conventional cylinder with mechanical bittings or wafers is needed. Moreover, the embodiments of these drawings enable variations in depth to be accommodated, since a plug is not required to be seated to a prescribed depth in a cylinder shell. 
         [0089]      FIG. 13  shows an electronic lock  74   a  of the invention, similar to the lock  74  described above in most respects and applicable to a cam, cabinet, plunger lock or similar lock, but with a specially shaped driver  102  extending back for engagement with a latching or locking device (lock unit) to be secured on the back side of a door, drawer, panel, etc. The driver  102  is operable by rotating the knob  12  as described previously, or a handle as shown and discussed below. The driver may permanently attach to the knob or handle, or it can be an insert, whereby different lengths of driver can be used for different panel thicknesses. 
         [0090]      FIG. 14  is an assembly view indicating the electronic lock unit  74   a , with the lock driver  102  being essentially straight and perpendicular to the back of the unit and having a square cross sectional shape, and a cam lock or lock unit  104  with a similar specially shaped hole or receiving socket  106  in a rotatable plug  108 . As noted above, it should be understood that any slide-in keyed cross-sectional shape can be employed, square being one example, but also including, flat, star-shaped, splined, D-shaped, etc. It can be seen, by comparison to  FIGS. 3-5 , that the embodiment of  FIG. 14  is an alternative to that earlier-described embodiment. 
         [0091]      FIG. 15  shows the electronic lock unit  74   a , with the specially shaped driver  102 , positioned for assembly into a different type of lock, in this case a cabinet lock  110  of the type shown in  FIG. 9  as the cabinet lock  86 . In this case, of course, the special driver  102  extends into a complementary hole  106  in a rotatable plug  108  of the cabinet lock  110 , rather than a blank plug extending into a plug opening as in the embodiment of  FIG. 9 .  FIG. 16  shows a similar arrangement, with the cabinet lock  110   a  having a latch or dead latch  112  rather than a deadbolt. In  FIG. 16  the cabinet lock unit  110   a  is shown without an extending barrel or shell  114  as in  FIG. 15 . In some cases, especially metal cabinets (such as file cabinets), there is no need for this projection  114 . The components can be arranged so that the fasteners shown extending back from the housing will not interfere with the lock unit  110   a . The lock unit  110   a  can be mounted onto the unit  74   a  sandwiching the door panel or each can be mounted independently to the panel. In  FIG. 15  as well, the extension  114  can be eliminated. 
         [0092]    The lock unit as shown in  FIGS. 15 and 16  provides for more universal connections and standardization of lock components as compared to the earlier-described embodiments. A manufactured line of cabinets, drawers, doors, etc. can have prescribed types of lock units, with a cam lock, cabinet lock, plunger or other types as described below, and all can be arranged to be engaged with the electronic lock unit  74   a  of the invention. Depths due to different thicknesses of drawers, doors, etc. can be accommodated without providing a series of different shell depths for the shell  114  extending forward from the mechanical cam lock or cabinet lock or other lock unit. The electronic lock unit  74   a  can be universal for many different situations and applications. 
         [0093]      FIG. 17  shows the same electronic lock unit  74   a  of the invention being applied to an oval shaped plunger lock  117 , again with a matching rotatable plug  108  for receiving the special driver  102 .  FIG. 18  shows the lock unit  74   a  being applied to a round shaped plunger lock  118 , again with a plug  108  matched to the driver  102  of the unit  74   a .  FIG. 19  shows the same electronic lock unit  74   a  being applied to an electric switch lock  119 , again with a plug  108  matched to the driver  102 . 
         [0094]      FIG. 20  shows a modified electronic lock unit  74   b  being applied to a screw type T handle lock  120 , again having a plug  108  matched to the special driver  102 ;  FIG. 21  similarly shows the modified electronic lock unit  74   b  being applied to a cam type T handle lock  121 , with the plug  108  and driver  102  matched. In both  FIGS. 20 and 21 , the back side of the lock unit  74   b  has a recess  124  that accommodates the outward extension  126  of the T handle lock, to the extent it protrudes out from the surface of the door, drawer, etc. When the electronic lock unit  74   b  is secured fast to the door, drawer or panel it appears integrated with the T handle lock  120  or  121 . Note that in this case, the invention involves a lock unit  120 ,  121  that is assembled onto the front of the door or drawer, with the electronic unit  74   b  installed over it. 
         [0095]      FIG. 22  shows a modified electronic lock unit  74   c  of the invention, in this case with an integral flange  130  designed to allow recess mounting of the base part  132  of the housing.  FIG. 22A  simply shows a variation, applicable to all embodiments, wherein the rotatable handle  12  is replaced with a lever  134 , which may be needed for handicap access or for other purposes as desired. The term cam lock as used in the claims is intended to refer to a cam lock or cabinet lock, or a plunger lock or switch lock or T handle lock. Also, references to a knob or handle are to be taken as referring to any type of turning device provided to operate the cam lock manually. Further, reference to a panel of a door, cabinet or drawer is intended to refer to any access panel or a fixed panel from which an openable component is controlled. 
         [0096]    Note also that although a keypad is shown in the preferred embodiment above, the lock can be operated by a keypad in combination with an electronic key (used at the contact connection  22 ), or the keypad can be eliminated in favor of an electronic key alone. The term electronic access device refers to either type of electronic access. 
         [0097]    Also, the electronic lock housing  14  can be oriented vertically instead of horizontally, with keypad characters oriented 90° from what is shown. Further, the cam in the illustrated embodiment can be rotatable to various degrees to fit the application. 
         [0098]      FIGS. 31-33  show a lock  140  according to the invention. The lock  140 , which has a housing  142 , preferably has batteries within a battery compartment  144  shown on a side of the unit, and a terminal  145  is also included. The lock unit  140  is the sole electronic housing for a lock, and may be part of a cam lock or cabinet lock, as well as a locker lock or a driver for any kind of lock or key switch mechanism which is mounted on a panel behind the lock  140 . All of the drawings show different forms of this compact electronic lock unit. 
         [0099]    The lock  140  has a rotatable knob or handle  146  extending from the housing  142  (the handle could be a lever if required or desired). The lock  140  is preferably without a keypad but in other respects is preferably very similar to the lock shown in U.S. Pat. No. 8,495,898. The lock unit  140  is very compact and if it has onboard batteries they can be small standard cells or coin cell type batteries. A status indicator light is shown at  148 . 
         [0100]    The lock is operated using a key device such as that shown in copending application Ser. No. 12/072,557, and related U.S. Pat. No. 7,336,150, and the disclosure of both are fully incorporated herein by reference. The key device preferably has batteries and makes contact with the electrical contacts  150  shown in the terminal  145  at the front side of the housing. The lock unit  140  can be without batteries; if it does have onboard batteries within the housing  142  (within the compartment  144  shown in  FIG. 31 ), then a set of key devices for the lock, or for a series of similar locks, can include small key contact devices having no battery and having two contacts for engagement with two of three contacts  150  shown in the terminal  145  on the lock. A master or manager&#39;s key device can be somewhat larger, with onboard batteries carried in the key device, with three contacts for engaging with all three of the contacts  150  in the terminal  145 . This enables a manager to use the special key to provide jump power to the lock  140  in a case where the lock&#39;s battery is low or when a user of the lock has forgotten his key or the key is somehow nonfunctional, or for both situations simultaneously. The terminal  145 , and the contacts on the key, can be structured in accordance with the drawings and description of copending application Ser. No. 12/072,557, as well as U.S. Pat. No. 7,336,150, for protection of the contacts of both the lock and the key and to ensure proper engagement. 
         [0101]      FIGS. 32 and 33  show one form of the lock  140  in a side or top elevation view, installed in  FIG. 32  in a panel  152  such as on a door, file cabinet, drawer, locker door, or other type of application. In  FIGS. 32 and 33  the lock is essentially in the configuration of a cam lock, wherein the handle or knob  146  connects directly with a cam lock cylinder unit (without tumbler pins or wafers)  154 ; specifically, the handle  146  turns a moveable member, e.g. a rotatable bolt or core  156  which rotates within the fixed cylinder unit  154  when permitted by the electronics.  FIG. 32  shows one example of latching with the cam lock device, with a metal arm or cam  158  rotatable with the bolt  156 , to be rotated using the handle  146  when permitted. A nut or threaded ring  160  retains the lock unit to the panel  152 , in a position such that the arm or cam or latch  158  engages behind a ledge or in a slot or other appropriate element when the door, drawer, locker door, etc. is to be in a locked condition. 
         [0102]    The lock unit  140  is extremely compact and can have dimensions of, for example, about two inches in width (the horizontal direction as seen in  FIG. 33 ); about ⅞ inch in height (the vertical direction in  FIG. 33 ); and about inch in thickness. More broadly the size is in the range of about ½ to 3 inches wide, about ⅞ to 1⅛ inch in height and about ⅜ to 1 inch thick. 
         [0103]      FIGS. 34A and 34B  show a typical cam lock shell  170  mounted on a door or drawer  171 , with the typical cam lock plug removed, and replaced with an electronic lock  174  with a cylinder plug  175 , retrofitted into the shell  170  in accordance with the invention. The plug  175  is a “blank” plug that will operate the lock when installed via a retainer clip or pin  176 , with the electronics as discussed above to control access. In  FIG. 34A  the electronics housing  174  has a recess  178  shown in dashed lines, surrounding the extending plug  175 , for the purpose of accommodating the slightly protruding face  180  of the cylinder shell  170  as installed in the drawer or door  171 . Many cam locks used in furniture have this type of front loaded plug which can also be removed for service and re-keying purposes. This is similar to what is shown and discussed above, but with the more compact electronic lock unit of the type shown in  FIGS. 31-33 . This continuation is advantageous in applications where an existing mechanical lock is fitted to the cabinet that has a brand-specific cam device or other linkages that are attached to the cam device for operating multiple drawers or doors. 
         [0104]      FIG. 35A  shows the door or drawer front  182  with a lock mounting hole  180   a . This hole may be round as shown or a single or double “D” shape commonly used in the industry. The mounting can be similar to  FIGS. 32 and 33 .  FIGS. 35A-35C  show a panel, drawer or door  182  with a conventional cam lock removed.  FIG. 35B  shows the compact self-contained electronic lock  174  of the invention as a replacement installed through the hole  180   a  in the same manner as the mechanical lock it replaces. 
         [0105]    Reference is made to U.S. Pat. No. 8,495,898 (incorporated by reference herein) regarding other applications of the electronic lock generally as shown in  FIGS. 31-33  and  FIGS. 34A and 34B  herein. The compact lock of the invention can be formed with a cylinder plug type rear extension that fits into an existing cabinet lock with bolt or latch of the types as shown, for example, in  FIGS. 9-12  of that patent. 
         [0106]      FIG. 36  shows another application of the compact lock of the invention, similar to that of  FIGS. 13-14 . Here, a compact electronic lock  140   a  operates similarly to the lock  140  of  FIGS. 31-33  but has a simple spindle or driver  183  extending back from the rear of the unit, essentially straight and perpendicular to the back of the unit and having, for example, a square cross sectional shape. The driver  183  fits in driving contact with a similarly shaped driver hole or receiving socket  184  in a cam lock or lock unit  186 . The receiving socket  184  is in a rotatable plug  188  of the lock unit  186 . As discussed above, it should be understood that any slide-in keyed cross-sectional shape can be employed for the driver  183 , square being one example but also including flat, star-shaped, splined, hex, D-shaped, etc. The lock shown in  FIG. 36  is an alternative to other lock arrangements such as  FIGS. 34A-34B  wherein a dummy cylinder plug is the element that extends to the rear of the electronic lock unit. 
         [0107]      FIG. 37  shows another application of the compact electronic lock unit  140   a , with the specially shaped driver  183  positioned for assembly into a different type of lock, in this case a cabinet lock  190  of the type that has an off-center rotatable plug  192 , a replacement for a conventional cabinet lock device having internal pins and tumblers that act between the plug  192  and the cylinder shell  194 . Here, the driver  183  extends into a complementary hole  196  in the rotatable plug  192 . Note that the drawing shows a retractable spring latch or dead latch  198  in this embodiment, but instead there could be a deadbolt. This is similar to an embodiment described earlier and in U.S. Pat. No. 8,495,898, but with the abbreviated and compact electronic lock  140   a  of the invention. As explained in that patent, this application of the lock provides for more universal connections and standard provision of lock components as compared to some of the earlier-described embodiments. A manufactured line of cabinets, drawers, doors, etc. can have prescribed types of lock units, with a cam lock, cabinet lock, plunger or other types, and all can be arranged to be engaged with the electronic lock unit  140   a  of the invention. Depths to the different thicknesses of drawers, doors, etc. can be accommodated without providing a series of different shell depths for the shell  194  extending forward from the mechanical cam lock or cabinet lock or other lock unit. The electronic lock unit  140   a  can be universal for many different situations and applications. Note that a single threaded stud  199  is shown in this and other drawings for securing the compact lock to a door, drawer, etc., but any suitable form of attachment can be used. In the case of  FIG. 37  the stud  199  or studs (or threaded holes) must be wide enough out from the driver  183  that they will clear the cabinet lock unit  190 . 
         [0108]      FIG. 38  shows a modified electronic lock unit  140   c  of the invention, in this case with a flange  210  designed to allow recess mounting of the base part  212  of the housing. The flange  210  may be integrally formed with the base part  212 . Thus, the flange  210  is configured to engage against the outside surface of a door or drawer. It should be understood, as pointed out earlier, that the rotatable knob or handle  146  shown in  FIG. 38  can be replaced with a lever, which may be needed for handicap access or for other purposes as desired. 
         [0109]      FIGS. 39A through 39C  show a self-contained electronic lock unit  140   d  similar to the locks shown above and including a cylinder  215  with an appropriate actuator such as a cam or other latching device, or simply with a driver such as shown at  183  in  FIGS. 36 and 37 . In this case the electronic lock device  140   d  is mounted behind the panel  216  of a door, drawer, etc. in a through-the-panel mounting, with the knob or handle  146  and the terminal  145  having an adequate mounting depth protruding from a base plate  218  to extend through the thickness of the panel  216 , as shown in  FIGS. 39B and 39C . The base plate  218  installs flatly against the back side of the panel  216  and is secured by appropriate fasteners  219  through holes  220 . The depth to which the knob or handle  146  and the terminal  145  are floated out from the base  218  is matched to the type of panel  216  to which the lock is to be secured (e.g. wood panel, steel panel, etc.). It should be understood that although a cylinder structure is shown in  FIG. 39C , this could simply be a cam such as shown at  158  in  FIG. 32 , or a latch such as shown at  190  in  FIG. 37  or another type of engaging device for locking the panel to other structure. Depth concerns may dictate that a cam or latch be provided immediately behind the housing  222  shown in  FIG. 39C , without the cylinder structure  215  extending back to increase the depth. A battery compartment (not shown) can be located similarly to what is shown in the locks described above, with a battery door located for maximum convenience. In a low-battery condition a power jump can be made via the terminal  145  as described earlier. 
         [0110]      FIGS. 40A through 40C  are similar to  FIGS. 39A through 39C , but show a keypad  225  on an electronic lock device  140   e . This lock device  140   e  is similar to above-described embodiments, but with the lock unit mounted behind the panel  216   a  in a through-the-panel mounting, as described with respect to  FIGS. 39A-39C . Holes  226 ,  228  and  230  are provided in the panel for this purpose. Note that the holes  228  and  230  could be replaced by a singular rectangular opening. Again, a different latching or securing mechanism can be included instead of the cylinder structure  215  shown in  FIG. 40C , for the reason explained above for  FIGS. 39A-39C .  FIG. 40D  shows that, as an alternative to a battery compartment located accessibly in the housing of the lock  140   e , the battery can be in a separate battery pack or casing  238  as shown. The battery  238   a  connects to the lock housing by a wire  238   b ; a magnet  238   c  can be provided to mount the battery on a steel panel, or adhesives or Velcro (hook and loop fasteners) can be used. 
         [0111]    The term cam lock as used in the claims is intended to refer to a cam lock or cabinet lock, or a plunger lock or switch lock or T handle lock or locks of similar application. Also, references to a knob or handle are to be taken as referring to any type of turning device provided to operate the cam lock manually. Further, reference to a panel of a door, cabinet or drawer is intended to refer to any access panel or a fixed panel from which an openable component is controlled, in situations where ingress is provided but not egress, as in office furniture. 
         [0112]    It should also be understood that the manually-operated locks described above relative to all figures could instead be automatic, with electromagnetic operation to retract a latch or rotate a cam, such as a solenoid or miniature motor, both of which are referred to as an electromagnetic actuator. 
         [0113]    The term driver, although used above to refer to the cross-section specific driver  183  in  FIGS. 36 through 38 , more generally refers to an element that transfers the rotational motion of the knob or handle to the rear of the lock device, which can be through a cylinder, or via a dummy plug or other element, including a cross-section specific driver or spindle. 
         [0114]    The term “cylinder” or “cylinder unit” as used herein is intended to mean at least a collar extending part way back from the housing, not necessarily as deep as the driver within the cylinder or collar, the driver being within the collar and rotatable within the collar. 
         [0115]      FIG. 41  shows a panel with another application of a compact lock  240  of the invention, similar to that of  FIG. 35C  but with the additional input device  241  designed to receive an IButton input, which can be the primary means of accessing the lock. 
         [0116]      FIG. 42  shows another application of a compact lock  250  of the invention, similar to that of  FIG. 35C  but with an additional input device  242  designed to receive wireless input from wireless access credentials such as RFID tags, proximity access cards and other wireless access technologies. The wireless technologies are commonly used for accessing the lock devices of the invention, reducing the number of credentials the user has to carry. Additionally the lock devices may be fitted with Bluetooth or similar interfaces to communicate with handheld small computers, PDAs or mobile telephones for access as well as uploading and downloading data to and from the lock devices. The lock driver may also communicate with specially designed holes as part of a network and receive valid access data and send audit data or maintenance data or other desired data. This data may be access programming data or data containing audit trail or usage information as well as application specific data for the usage of the cabinet such as insertion or removal of files or other items to and from the cabinet. 
         [0117]      FIGS. 45 and 46  also show the lock device of the invention with an antenna  233  for wireless network connection. This connection may be an Ethernet connection or Bluetooth or similar connection or both. The lock units  260  and  270  shown in  FIGS. 45 and 46  (similar to those of  FIGS. 40A and 39A ) are also equipped with a receptacle  234  for direct network connection (as an alternative to wireless) as well as a power receptacle  235  for external (line) power if required or desired. A network can be used to control what codes have access to a series of cabinets, drawers, etc. Such a network will include a terminal or central control system which can simply be a microprocessor with a database listing all locks. A laptop or hand held computer device is all that is required, or a network hub connected to a group of locks, wired or wirelessly. 
         [0118]    With the central control a manager connects to any one lock or all locks when desired, to update which “keys” or codes will have access, and even the times of permitted access if desired. Each lock can include a processor to receive the control signal and to set the lock&#39;s electronics to allow access by employees A, B, C and D but not employee E, for example. This is changeable at any time, instantly. The programming and electronics for this networking and control function are well within the ability of a person of ordinary skill in the art. A panel hole  231  is provided for the antenna  233 . A single panel opening could be provided for all projecting elements, or one for the antenna, one for all keys and the terminal  145 , and one for the knob, or other similar arrangements. Note that the antenna and/or direct network receptacle, as well as the line power connection  235 , can be included on any of the embodiments described above. 
         [0119]    The locks of the invention, having the antenna  233 , can have internally, connected to the antenna, a near-field communication (NFC) device that can communicate with a hand-held wireless device in proximity to the lock, for accessing the lock and also for purposes of lock settings and audit of lock access events. This near-field signal can be triggered to be activated by a smartphone (with appropriate programming, a phone app) or other portable electronic device, held close to the lock. The lock security and accessing of the lock could work in several different ways; the interrogation can be made either by the hand-held device or by the lock (with the lock having access to a database). One way is that the smartphone or other device must first authenticate the user, which could be by fingerprint, face recognition, voice recognition or simply a PIN. This will improve security. Upon authentication the hand held device can send an operating code to the lock. If the lock unit is not line powered but powered by batteries the user may “wake up” the lock by pressing a key on the lock prior to sending the code. The authentication and its method can be in accordance with the individual app and its objectives. A NFC capable hand-held device can send a signal containing the access code to operate the lock with or without prior authentication of the user of the hand-held device. 
         [0120]    In another embodiment where the standalone lock unit either does not have a database of authorized codes or is not connected to a network for updating its database of valid codes, on authenticating the user the phone or hand-held device will send out a code asking for the lock&#39;s ID. This will “wake up” the lock, the electronics of which have been on a standby mode when not used, so as not to draw power (waking the lock could also require pressing a key on the lock&#39;s terminal, especially where the lock is battery-powered). On receiving the lock ID, the phone can, over the Internet or over a local network if desired, send the data of the user and the lock desired to be accessed, using the data connection of the phone. A database, which can be remote, will then send back an allowance or rejection code to the phone regarding this request for access. On receiving an allowance code from the access control database, the phone via its programming will transmit an access code to the lock, causing the lock to open. This protocol can also be used for updating the database of the lock if it has one. For audit purposes, the lock can then send a verification code back to the phone, if the lock was actually accessed. This code will be transmitted via the phone to the access control database. A denial of access can also be transmitted to the access control database for audit purposes. If receiving a rejection code the phone app will inform the user that access was denied. In an NFC system a new employee, for example, not currently in the system, can have the employee&#39;s new code added to the system using the NFC device. The update can include whether the code is to be one-time access, permanent access, or limited access. 
         [0121]    In a different operational protocol the lock can have an RFID reader that sends out an interrogating signal to a hand-held device or credential. Although such a credential could be a card containing an RFID tag, a smartphone can have a program or app that mimics an RFID tag transmitting an ID signal, or transmitting, receiving and calculating algorithms to authenticate the signal sent back by an RFID tag, in order to provide access. The sending of the code for access by the phone may be subject to prior user authentication as outlined above. In this case the access decision is provided by the lock electronics, rather than by the phone or other hand-held device, using database information as in the system described above. 
         [0122]    Note that RFID and NFC are closely related wireless communication technologies, both used for a large number of applications including access control, asset and inventory tracking, etc. RFID was the precursor to NFC, and the range of frequency utilized in RFID has a frequency band in common with NFC. RFID involves unpowered tags capable of sending back a simple response to a reader, using the power of the reader&#39;s transmission. NFC operates at 13.56 MHZ and is an extension of HF RFID standards. NFC is capable of more complex two way communication interactions and is thus more versatile in that respect than RFID. NFC is limited to communication at close proximity, such as 5 cm or less. Also, only a single NFC tag can be scanned at one time by a reader, whereas many RFID tags can be scanned simultaneously. NFC is available in a great many mobile phones or smartphones. 
         [0123]      FIGS. 43 and 44  show panels  232   a  and  232   b  with lock devices  240   a  and  250   a  similar to those shown in  FIGS. 41 and 42  but configured for installation through the panel of the door, cabinet or drawer. In this case the battery access will be from behind the lock device. The lock is mounted to studs on the panel through the mounting holes at each end or the unit may be mounted with screws or other fasteners directly to the panel from behind. Note again that common openings rather than individual holes can be provided in the panel for the knob, terminal, and input device. 
         [0124]      FIGS. 47 and 48  show through-the-panel lock devices  280  and  290  as shown in  FIGS. 43 and 44  fitted with the same apparatus for network and power connections  234  and  235  (and antenna  235  if needed) discussed above for  FIGS. 45 and 46 . 
         [0125]    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 these preferred embodiments 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.