Abstract:
An electronic security system for a parking meter includes a vault door having a spring-biased contact terminal for making breakable electrical contact with a housing hinge bracket contact terminal mounted in a vault opening. An electronic lock control circuit is able to communicate with a meter control (coin counting/auditing) circuit in the meter portion of the system through the vault door/housing hinge bracket contact terminals, thus eliminating a direct cable connection between the lock circuit and the meter circuit. The spring-biased contact may be substituted by equivalent breakable electrical contacts such as optocoupler contacts.

Description:
[0001]    This application is a continuation of application Ser. No. 09/837,175 filed Apr. 19, 2001, which claims priority under 35 U.S.C. § 119(e) from provisional application Serial Nos. 60/198,385 filed Apr. 19, 2000, and 60/242,142 filed Oct. 23, 2000. 
     
    
     
       BACKGROUND OF THE INVENTION  
         [0002]    1. Field of the Invention  
           [0003]    This invention relates generally to electronic security systems, and more particularly to electronic security systems for money-containing devices such as parking meters, which must be periodically accessed by a collector in order to retrieve the funds accumulated in the device. While the preferred embodiment will be described with respect to a parking meter configuration, the invention could be used with other devices, such as pay telephones, bill changer machines, fare card machines, or vending machines, where a data collection and storage section of the device is separate from the money-containing vault section of the device.  
           [0004]    2. Background and Prior Art  
           [0005]    Typically, the collection of money from coin or currency operated devices such as parking meters, pay telephones, transit system fare card machines or the like is a costly and burdensome operation. For instance, a company may own tens or even hundreds of thousands of pay telephones for which tens or hundreds of thousands of keys must be kept in order to prevent the loss of a key from requiring the changing of locks on thousands of devices which would operate with the lost key.  
           [0006]    Another problem involved with the collection of funds from currency operated devices is the possibility of fraud or theft by a collector. Typically, a collector should remove a locked coin box from the device and replace it with an empty lock box to which he does not have access. However, it is possible that a removed coin box will not be replaced with another lock box but rather will be replaced with an unlocked receptacle which can be later removed by that collector before turning in his key at the end of the collection shift.  
           [0007]    Yet another cost involved in the collection process is the sheer manpower required for the task of distributing, collecting, and keeping track of many thousands of keys on a daily basis.  
           [0008]    Another shortcoming in the art pertains to electronic parking meters having coin counting or auditing circuitry for keeping track of the amount of revenue collected by the meter. Such meters have separate upper (i.e. meter) and lower (i.e. coin vault) housings, wherein coins are fed into the upper housing, pass through a coin identification mechanism, and drop into a secure coin box or vault located in a locked lower housing. The upper housing has a coin counting/auditing circuit (typically provided on a circuit board) coupled to the coin identification mechanism, and stores information relating to the count of coins received since the last time the device was emptied. The coin counting/auditing circuit communicates inserted coin information to a meter circuit, which adds time to the meter in response to the monetary amount of coins inserted into the meter, according to a preprogrammed algorithm which specifies the number of minutes added for each domination of coin. The meter circuit typically is coupled to a display or other visual indicator that displays the amount of time remaining on the meter. The lower housing includes an electronic lock mechanism for interfacing with an electronic key system for accessing the coin vault.  
           [0009]    In such systems, the coin audit information is retrieved from the electronic circuitry in the upper housing either by radio frequency transmission from the circuit in the upper housing to a separate handheld receiver device, or by transferring the information to a “smart” card inserted into a card slot provided in the upper housing. Alternatively, the circuitry in the upper housing may be wire-connected to the electronic lock circuitry within the lower housing containing the coin vault. Coin count information is passed from the circuit board in the upper housing to the lower housing by a flexible wire conductor hard-wired between the two circuit boards, from where it is sent to a handheld electronic key device once authorization has been verified. In such systems, a “living hinge” was created by a flexible wire between the two housings, and thus presented a poor design from an engineering and security viewpoint. Problems encountered with this system include frequent damage to the flexible wiring, due to pinching of the wiring between the door and the vault and due to wear from continued opening and closing of the door.  
           [0010]    Parking meters typically are located on the streets of major cities, and are subject to vandalism and break-in attempts. The construction of prior art vault doors rendered them readily subject to such attacks by using simple tools such as a hammer and driver or chisel to punch the lock cylinder into the door and thereby gain access to the vault.  
           [0011]    The electronics in the meter stores a large amount of data in addition to collected coin information. For example, the meter circuitry may store its status, meter identification information, zone information, e-cash purchase information, and profile data. It would be desirable to enable such data to be modified in the meter without the necessity of replacing the meter circuitry.  
           [0012]    Although electronic security systems are known and have been used for various purposes, see e.g. U.S. Pat. Nos. 4,789,859, 4,738,334, 4,697,171, 4,438,426, applicants are unaware of any which specifically address the problems noted above. An example of a prior art vending machine including coin count audit information circuitry is disclosed in U.S. Pat. No. 4,369,442.  
         SUMMARY OF THE INVENTION  
         [0013]    The present invention provides an electronic security system which overcomes the problems mentioned above and significantly reduces collection costs. 
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0014]    The present invention will become more fully understood from the detailed description given hereinbelow and the accompanying drawings which are given by way of illustration only, and are not limitative of the present invention, and wherein:  
         [0015]    [0015]FIG. 1 is an exploded view of a vault door assembly according to one preferred embodiment of the present invention;  
         [0016]    [0016]FIG. 2 is a perspective view of a two-part parking meter housing assembly used in one embodiment of the present invention;  
         [0017]    [0017]FIG. 3 is a partial cut-away view of the vault door showing the installation of a solenoid blocker tab according to the invention;  
         [0018]    [0018]FIG. 4 is a partial cut-away view of the vault door showing the solenoid blocker tab removed to enable operation of the solenoid according to the invention;  
         [0019]    [0019]FIG. 5 is a perspective detail view of the solenoid blocker tab according to the invention;  
         [0020]    [0020]FIG. 6 is an elevational view of the vault door opening according to a preferred embodiment of the invention;  
         [0021]    [0021]FIGS. 7A and 7B are elevational and side views, respectively, of the vault door according to the invention showing the details of the electrical spring contacts;  
         [0022]    [0022]FIG. 8 is an exploded view of the housing hinge bracket assembly according to a preferred embodiment of the invention; and  
         [0023]    [0023]FIGS. 9A and 9B are data flow tables for the meter, lock and access device according to a preferred embodiment of the invention. 
     
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS  
       [0024]    [0024]FIG. 1 shows an electronic vault door for a parking meter according to a preferred embodiment of the invention. The parking meter housing  200  is shown in FIG. 2. The housing  200  includes an upper or meter half  201 , and a lower or vault half  202 . A pair of through-holes  205  provides a conduit between the two halves of the housing for wire conductors (to be described in detail below). The electronic vault door is mounted against hinge brackets  204   a - 204   b  in the vault opening  203 . The vault door is locked in place over the vault opening  203  by rotating the plug assembly  2 , which turns a locking cam  12  that is coupled to bolts  10 . The cam  12  is turned to a locking position wherein the bolts  10  are moved outwardly and behind the brackets  204   a - 204   b  in the vault opening  203 , thereby locking the vault door in place over the opening  203 . To unlock the vault door for access to the vault, the cam  12  is turned in the opposite direction wherein the bolts  10  are retracted inward towards the center of the vault door, thereby allowing the service personnel to remove the vault door from the vault opening and to gain access to the contents of the vault.  
         [0025]    As shown in FIG. 1, the vault door assembly  100  includes a metal vault door  1 , a plug (lock cylinder) assembly  2  that is mounted inside a shell  3 , which is inserted into a central aperture  101  in the vault door  1  and retained rotationally therein by shell retainer  11 . A shell retainer bushing nut  4  is screw-threaded into the aperture  101  to retain the shell and plug assembly securely mounted in the vault door. A hinge assembly  8 , bolt retainer bracket  9 , and solenoid cover  15  are securely mounted to the vault door  1  with tri-groove security screws  16 . Bolts  10  are held by retainer bracket  9 . Pins  104  on bolts  10  are located inside grooves  105  in locking cam  12 . A cam shaft  102  of plug assembly  2  is inserted into cam shaft opening  103  of locking cam  12  and retained by cam spacer  13  and retainer ring  14 . A rubber door rest  19  is attached to the top of the vault door with a screw  20 . The door rest  19  is used as a rest for the vault door  1  when removed from the vault.  
         [0026]    A solenoid  6  is nested on the vault door  1  within a solenoid bracket  5 . The solenoid  6  includes a plunger  106  that is normally spring-biased in an extended position (i.e., when the solenoid is not energized) that blocks rotation of the locking cam  12 . A lock control circuit  17  in the form of a circuit board is mounted in a recess in the vault door, and is coupled via wire conductor(s) to a contact terminal on the face (not shown) of the plug assembly  2 . The circuit board  17  also is coupled via wire conductor to the solenoid  6 .  
         [0027]    The control circuit  17  communicates with an electronic or electronic-mechanical key (not shown) inserted into the keyway of the plug assembly  2 . The electronic/electronic-mechanical key contains a contact terminal that makes electrical contact with the terminal on the face of the plug  2  when the key is fully inserted into the keyway. When the control circuit  17  determines that an authorized key is inserted into the keyway of the plug, the control circuit energizes the solenoid  6 , causing the solenoid plunger  106  to retract, allowing the key to turn the plug (and thereby rotate the locking cam  12 ) to retract the bolts  10 . The operation of the electronic security system is described in U.S. Pat. No. 6,005,487 issued Dec. 21, 1999 to the same assignee as the present application, the disclosure of which is hereby incorporated by reference in its entirety. Accordingly, the description of operation will not be further described herein. The components  2 - 14  of the vault door assembly are covered by solenoid cover  15  which is mounted to the vault door via the screws  16  as shown.  
         [0028]    A contact base assembly  7  also is mounted on the vault door  1 . The contact base assembly  7  includes a pair of metal spring contacts  107   a,    107   b,  which are connected to the lock control circuit  17  via wire conductors (see also FIGS.  7 A- 7 B). As shown in FIG. 6, two hinge brackets  204   a  and  204   b  are provided adjacent to the vault opening  203 . Hinge bracket  204   b  includes a pair of flat-head metal contacts  602   a  and  602   b,  which make contact with the springs  107   a  and  107   b  of the vault door  1  when the vault door is locked in place in the vault opening. As shown in FIG. 8, contacts  602   a  and  602   b  are connected to an interface cable  87 , the other end  87   a  of which is connected to an input/output terminal of the meter electronic circuit (not shown) located in the meter half  201  of the housing  200 . The interface cable  87  is threaded through one of the through-holes  205  as shown in FIG. 2. The metal contact pins  602   a,    602   b  are inserted into the bracket  204   b  via insulating washers  83 ,  84 . Spacers  85  are provided on the ends of the contact pins  602   a  and  602   b  for connection of the wire terminals  87   a - 87   c  of the interface cable  87 , which are secured to the contact pins with lock nuts  86 . A wire form retainer  89  mounted to the bracket  204   b  with a screw  88  includes hook ends  801   a  and/or loop ends  801   b  through which the interface cable  87  is threaded. The wire form retainer is made of a stiff wire which does not easily bend, and it is oriented in a direction into the vault and away from the vault opening. The wire form retainer  89  functions as a guide to keep the interface cable  87  away from the vault opening and the vault door during access/reinstallation operations so as to avoid damage to the cable during collection operations.  
         [0029]    According to another aspect of the invention, as shown in FIGS.  3 - 5 , a blocker tab  301  is provided to disable the functioning of the solenoid plunger  106 . The blocker tab is used in installations where no electronic lock functions are implemented, but only mechanical locking functions are provided. Such installations can be later upgraded to provide the more sophisticated electronic security/monitoring functions by adding or activating the lock control circuit board.  
         [0030]    The blocker tab  301  contains two bent end tip portions  501   a  and  501   b  as shown in FIG. 5. The tab may be made of any relatively stiff material, and is preferably made of plastic. As shown in FIG. 3, the tab  301  is inserted between the solenoid plunger  106  and the plunger stop  302  (see also solenoid bracket  5 , FIG. 1) such that the end tip portions  501   a  and  501   b  force the plunger  106  to its retracted position within the solenoid  6 . At the time that the solenoid  6  needs to be activated, the blocker tab  301  is pulled out from between the plunger  106  and the plunger stop  302 . This releases the plunger to its fully extended position against the plunger stop  302  as shown in FIG. 4.  
         [0031]    [0031]FIGS. 9A and 9B illustrate various data flows between the parking meter circuit, the electronic lock circuit, and the handheld access device. When the meter is in a normal (operative) state, the lock is powered down. Time may be purchased on the meter either by insertion of coins into the provided coin slot, or by an electronic cash (“e-cash”) transaction. Upon such purchase, the meter powers up the lock and transmits the purchase information to the lock. The lock then stores the information in an appropriate memory location, and sends back to the meter an acknowledgment signal indicating that the purchase information was successfully transmitted to the lock and processed. After a predetermined time period has elapsed with no additional purchase activity, the meter removes power from the lock.  
         [0032]    Upon a change in meter status (such as from a ready state to a disabled state, etc.) the meter powers up the lock, waits to receive a ready signal from the lock, sends to the lock the new status, and waits for an acknowledgment from the lock.  
         [0033]    When a collector inserts an access device into the lock, the access device provides power to the lock which places the lock in a wake-up state. The lock notifies the meter that a collection wake-up has occurred. The lock sends a challenge to the access device and waits for a response. If a correct response is received from the access device, the lock sends an acknowledgment to the access device. The access device then sends an open command and the current time to the lock. The lock sends the access time information to the meter circuit, where it is stored. The meter sends an acknowledgment to the lock, and the lock circuit then enables the lock to be opened by the collector. While the vault door is open, the lock circuit provides from its memory to the access device memory data including coin data, e-cash purchases, the meter ID, the meter status, the meter profile ID, and the meter zone ID. Upon successful receipt of this information, the access device sends an acknowledgment to the lock circuit. When the collection is completed, the collector closes the vault door, reestablishing contact between the lock circuit and the meter circuit. The lock circuit then sends a “collection done” signal to the meter indicating the completion of the collection operation. The lock is powered down upon removal of the access device.  
         [0034]    The access device also may communicate directly with the meter circuit in a pass-through mode of operation, in which the lock circuit simply passes information signals between the access device and the meter circuit. In this mode, the vault door remains closed. The service personnel inserts the access device, which powers the lock, and the lock and access device conduct the challenge-and-response routine as described above. Upon receipt of the acknowledgment from the lock indicating a proper challenge response, the access device sends an audit command to the meter circuit. In this mode, the meter circuit sends audit data, including the data mentioned above, to the access device. The access device also may update the meter to load a new profile, change zone information, or change other meter information stored in the memory of the meter circuit. When the audit operation is complete, the access device sends a done signal to the meter. The meter then sends an “exit pass through” command to the lock to take the lock out of pass through mode and power down the lock. The meter alternatively may allow the lock to be powered down upon removal of the key from the lock interface.  
         [0035]    The invention being thus described, it will be apparent to those skilled in the art that the same may be varied in many ways without departing from the spirit and scope of the invention. For example, while the spring contacts in the illustrated embodiment are provided on the vault door, they may be provided equivalently on the housing hinge bracket. Additionally, while in the illustrated embodiments the contacts between the vault door and the housing hinge bracket are metal contacts, such contacts equivalently may be provided as optocoupler contacts, without metal-to-metal connection. These and all other such modifications are intended to be included within the scope of the following claims.