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CROSS REFERENCE TO RELATED APPLICATION  
       [0001]     This application claims the benefit of United States Provisional Patent Application No. 60/749,561, entitled “LOCK WITH OPERATION INDICATOR” and filed Dec. 12, 2005, the entire disclosure of which is hereby incorporated by reference. 
     
    
     FIELD OF INVENTION  
       [0002]     The invention relates to locking devices and to the inclusion of an indicator with the locking device to determine if the locking device has been operated.  
       BACKGROUND  
       [0003]     Locks and other securing devices are employed to secure all types of objects, containers, and spaces against unauthorized use. Locks are typically unlocked through the use of a key, combination, code, or other such authorizing mechanism. Many of these mechanisms allow for several people to have the ability to open the lock. For instance, keys can be duplicated and combinations can be memorized or recorded, such that multiple people can open a given lock. When a key is duplicated or several people have knowledge of a combination, it is difficult for an authorized user of the lock to determine if the lock has been opened without authorization since the lock was last closed.  
         [0004]     It is desirable to develop methods and apparatus through which an authorized user can determine if a lock has been operated since the last authorized use of the lock.  
       SUMMARY  
       [0005]     A lock that features an actuation indicator includes a lock body and a lock mechanism actuable between a locked and an unlocked condition. The lock mechanism includes a shackle that is movable relative to the lock body between a closed position corresponding to the locked condition in which the shackle is fixed in position with respect to the lock body and an open position corresponding to the unlocked condition in which the locking member is moveable with respect to the lock body. A lock sensor is configured to sense actuation of the lock mechanism and to send a trigger signal indicative of actuation of the lock mechanism. An actuation identifier generator in signal communication with the locking member sensor generates an alphanumeric actuation identifier in response to the trigger signal. The actuation identifier can be, for example, a random number or set of alphanumeric characters, or a serial number. The lock may include a display that displays the actuation identifier and actuation identifier recorder with memory storage for storing a succession of actuation identifiers and associated times and dates of actuation. 
     
    
     DESCRIPTION OF DRAWINGS  
       [0006]     In the accompanying drawings, which are incorporated in and constitute a part of this specification, embodiments of the invention are illustrated, which, together with a general description of the invention given above, and the detailed description given below serve to illustrate the principles of this invention. The drawings and detailed description are not intended to and do not limit the scope of the invention or claims in any way. Instead, the drawings and detailed description only describe embodiments of the invention and other embodiments of the invention not described are encompassed herein.  
         [0007]      FIG. 1  is a perspective view of a lock constructed in accordance with an embodiment of the present invention;  
         [0008]      FIG. 2  is a cross-sectional view of the lock of  FIG. 1 , illustrating a locking mechanism;  
         [0009]      FIG. 3  is a front elevation view of the lock of  FIG. 1 , showing the lock in an open position;  
         [0010]      FIG. 4A  is front elevation view of the lock of  FIG. 1 , showing the lock in a closed position and displaying an identifier on a digital display;  
         [0011]      FIG. 4B  is a front elevation view of the lock of  FIG. 1 , showing the lock in the open position and displaying an identifier on the digital display;  
         [0012]      FIG. 4C  is front elevation view of the lock of  FIG. 1 , showing the lock in the closed position and displaying an identifier on the digital display;  
         [0013]      FIG. 5A  is a perspective view of the lock of  FIG. 1 , showing the digital display unilluminated;  
         [0014]      FIG. 5B  is a perspective view of the lock of  FIG. 1 , showing the digital display illuminated;  
         [0015]      FIG. 6  is a flow diagram of a method of using the lock of  FIG. 1 ;  
         [0016]      FIG. 7  is a cross section view of the lock of  FIG. 1 ; and  
         [0017]      FIG. 8  is a schematic diagram of an exemplary control system for the lock of  FIG. 1 . 
     
    
     DETAILED DESCRIPTION  
       [0018]     The Detailed Description of the invention merely describes embodiments of the invention and is not intended to limit the scope of the claims in any way. Indeed, the invention is broader than and unlimited by the disclosed embodiments and the language used in this specification, and the terms used have their full ordinary meaning.  
         [0019]     An embodiment of the invention provides for a lock including a locking mechanism, a sensing arrangement, a circuit, and a display. The locking mechanism is operable to selectively lock and unlock the lock. The sensing mechanism senses when the lock is operated. The circuit generates an identifier each time the sensing arrangement senses the locking mechanism is operated, and the display reveals the identifier each time one is generated.  
         [0020]     The invention will be described using a padlock. It should be understood this is for exemplary purposes only and the invention may be practiced with other types of locking mechanisms, such as for example, combination locks.  
         [0021]     As shown in  FIG. 1 , a lock  10  includes a lock body  12 , a shackle  14 , and a digital display  16 . The lock  10  also includes an actuation identifier generator ( FIG. 8 )located inside the lock body  12 . The lock  10  operates between open and closed positions. The shackle  14  is moveably coupled to the lock body  12  such that the lock  10  can move between the open and closed positions. As best seen in  FIG. 2 , the shackle  14  includes a long leg  18  and a short leg  20 . The lock  10  can move from a closed position to an open position by moving the shackle  14  upwards (with respect to  FIGS. 1 and 2 ) until the short leg  20  exits the lock body  12 , as shown in  FIG. 3 . The lock  10  can be move from the open position to the closed position by moving the shackle  14  downwards (with respect to  FIGS. 1, 2 , and  3 ) until the short leg  20  of the shackle  14  is inserted into the lock body  12 , as shown in  FIG. 2 .  
         [0022]     The lock  10  includes a locking mechanism by which the lock  10  can be locked and unlocked. The lock  10  generally needs to be unlocked for the shackle  14  to be moved from a closed position (shown in  FIG. 1  and  2 ) to an open position (shown in  FIG. 3 ). The lock  10  can be arranged such that the shackle  14  can be moved from the open position to the closed position only when the lock  10  is unlocked. Alternatively, the lock  10  can be arranged such that the shackle  14  can be moved from an open position to a closed position when the lock  10  is either locked or unlocked.  
         [0023]     The locking mechanism can be operated by inserting a key (not shown) into a key slot in a key cylinder (not shown). Typically, turning the key in a first direction unlocks the lock  10  and turning the key in a second and opposite direction locks the lock  10 . When the lock  10  in closed and locked, turning the key to unlock the lock  10  rotates a keeper  33  to release a pair of shackle retaining balls  31  and allow the shackle  14  to be moved upwards to open the lock  10 . As described above, the lock  10  can be arranged such that the key generally must maintain the locking mechanism in the unlocked state for the shackle  14  to move from an open to a closed position. Alternatively, the lock  10  can be arranged such that the locking mechanism may be in either an unlocked or a locked state for the shackle  14  to be moved from on open position to a closed position.  
         [0024]     As shown in detail in  FIG. 7 , a sensor  70  is mounted in the lock body  12  to sense when the lock  10  is operated. The sensor  70  can be a mechanical switch that is closed by contact with, for example, a leg of the shackle, or the shackle balls (not shown). The sensor  70  can be a photoelectric sensor that senses a proximity of, for example, a leg of the shackle without mechanical contact. The switch or sensor can be arranged to sense one or more different movements within the lock  10  that indicate operation. For example, a switch or sensor can be arranged to sense when the lock  10  moves from an open position to a closed position, or a switch or sensor can be arranged to sense when the lock  10  moves from a closed position to an open position. In addition, the switch or sensor can be arranged to sense any change in the state of the lock  10 . Such changes in state include, for example, the shackle  14  moving from an open position to a closed position, the shackle  14  moving from a closed position to an open position, the lock  10  being unlocked, the lock  10  being locked, or the lock  10  being sufficiently tampered with in an attempt to pick the lock  10 .  
         [0025]     The switch or sensor  70  can use a variety of methods in determining that the state of the lock  10  has changed. For example, the switch or sensor  70  can be positioned to sense movement of the shackle  14  during opening or closing of the lock  10 . The movement detected can be either upward movement of the shackle  14 , downward movement of the shackle  14 , rotational movement of either shackle leg  18 ,  20 , lateral movement of the shackle, or any other movement of the shackle  14 . Alternatively, the switch or sensor can be positioned to sense operation of the locking mechanism. The operations detected can be the insertion of a key or other object into a key slot or the turning of a key in the key slot. These movements and operations of the lock  10  can be sensed through a variety of methods. For example, a mechanical switch can be used. Alternatively, a photoelectric sensor can be positioned proximate to a shackle  14  to determine movement of the shackle  14  through changes in light waves or electrical current caused by the movement of the shackle  14 . Similarly, a photoelectric sensor can be positioned proximate to the locking mechanism to sense the insertion of a key or other object or the turning of a key. In addition to the embodiments described, this invention includes the use of any other switch or sensing mechanism known in the art that can sense a change in state of the lock  10  or movement of components in the lock  10 .  
         [0026]     Referring to  FIG. 8 , a schematic cross section of a display portion of the lock body  12  is shown. The display portion houses a circuit board  29  that includes an integrated circuit  21 , or set of integrated circuits, that is capable of driving the display  16 . The integrated circuit includes an actuation identifier generator  23  that generates a unique actuation identifier, such as a random combination of alphanumeric characters or a serial number, in response to a trigger signal on lead  71 . When the switch or sensor  70  has sensed that the lock  10  had been operated, the switch or sensor  70  generates a trigger signal on an associated trigger lead  71  indicating that the lock  10  has been operated. This signal is inputted to the integrated circuit and triggers the actuation identifier generator  23  to generate a new actuation identifier. The actuation identifier is displayed on the display  16 . A display illumination button  24  may also provide an input to the integrated circuit  21  that enables display of the actuation identifier for a limited duration of time to conserve power consumption. The displayed actuation identifier can be used by a user of the lock  10  to identify a particular instance of the lock  10  being operated. An actuation identifier recorder  27  is also included as part of the integrated circuit  21 . As will be described below, the recorder provides a memory function to the lock.  
         [0027]     Some of the components described above require electric power in order to operate correctly. A battery contained in the lock body  12  can supply this power. This battery can provide power to several components, including the switch or sensor, which senses change of state of the lock  10  and relays signals to other components in the lock  10 ; the integrated circuit, the actuation identifier generator; the actuation identifier recorder; and the digital display  16 , which reveals the identifier  22 .  
         [0028]     The actuation identifier recorder  27  provides for the storage of the actuation identifier associated with the current state of the lock  10 , along with storage of past actuation identifiers associated with past states of the lock  10 . In addition to generating an actuation identifier and relaying the number to the digital display  16 , the actuation identifier can be stored in the memory function so that it can be retrieved if the digital display  16  malfunctions. In addition, the actuation identifier recorder can retain an index of all actuation identifiers generated so that a user can determine information other than if lock  10  had been previously operated, such as for example, the number of times it has been operated.  
         [0029]     A time stamp can be associated with each actuation identifier generated and stored in the recorder  27 . This feature allows a user to determine the date and time that each lock  10  operation occurred. The actuation identifier recorder can include other information important to an authorized user. For example, the actuation identifier recorder can include information related to the type and quantity of goods in a secured container or the point of origin and destination of the container. Alternatively, the actuation identifier recorder can reside on a separate circuit from the actuation identifier generator  23 . Optionally, the lock  10  can include a data port (not shown), such as for example, a universal serial bus (USB), parallel port, or serial port to upload and download information from integrated circuits, the system board, or the digital display  16 .  
         [0030]     The digital display  16 , as shown, is a liquid crystal display (LCD). However, any mechanism known in the art for displaying an identifier is included in this invention. For example, the digital display can be a series of light emitting diodes (LED). Alternatively, the display may be mechanical as opposed to digital, such as for example, a series of mechanically or electrically driven wheels or tumblers. Although the exemplary illustration shows an eight digit number as the product of the random number generator, it should be understood that a set of numbers of any length can be produced by an integrated circuit and displayed on a digital display. In addition, the characters generated and displayed are not limited to numbers. The characters could be any symbols, such as for example, upper and lower case letters, ampersands, asterisks, and the like.  
         [0031]     The battery life can impact the performance and usefulness of the lock  10 . Therefore, efficiencies and conservation methods that prolong battery life are useful. For instance, the digital display  16  can be arranged so that the identifier  22  is selectively displayed. To continuously display an actuation identifier  22  when it is normally only read shortly after a lock  10  is closed and shortly before a lock  10  is opened is inefficient use of battery power. The integrated circuit or display  16  can be arranged such that the actuation identifier  22  is shown on the display  16  for only a period of time after the actuation identifier is generated. This period of time can be selected such that it is long enough for a user to note the actuation identifier generated. As best shown in  FIGS. 5A and 5B , an illuminating button  24  can be added to re-illuminate the digital display  16  once the period of time has expired. The actuation identifier can be retained by the digital display  16  or retrieved from the actuation identifier recorder when the illuminating button  24  is pressed.  FIG. 5A  shows the lock  10  after the display period has expired.  FIG. 5B  shows the lock  10  with in the display period after the illuminating button  24  has been depressed. With this arrangement, a user can depress the button  24  prior to opening the lock  10  to view the last actuation identifier generated  22  and compare the displayed actuation identifier  22  with the identifier associated with the last authorized closing of the lock  10 .  
         [0032]     One embodiment of an actuation identifier generator  23  is a random number generator that can be designed to generate, at random, a series of numbers or other characters to produce a generally unique identifier. Electronic random number generators are known in the art. In an embodiment of the invention, the generation of a random number or identifier is initiated by the electronic input signal on lead  71  from the switch or sensor  70 , produced when the lock  10  has been operated. Once this random number is generated, the identifier can be provided or revealed to a user of the lock  10 . The user can record or remember the number and associate that number with the specific instance of the operation of the lock  10 . This operation can be associated with a unique time, location, or event, or combination thereof.  
         [0033]     As shown in  FIG. 3 , one method of providing a user with the randomly generated number or identifier is to display the identifier  22  on a digital display  16 . The digital display  16  can be in electronic communication with the integrated circuit, such that each time a number is generated in response to the operation of the lock, the identifier  22  shown on the digital display  16  updates to correspond with the random number generated for that specific operation of the lock  10 .  
         [0034]     An arrangement where a random number is generated for each opening and closing of the shackle  14  is shown in  FIGS. 4A, 4B , and  4 C. In  FIG. 4A , the lock  10  is shown in a closed position, with the digital display  16  showing a first number  22 A generated the last time the lock  10  was closed.  FIG. 4B  shows the lock  10  now in an open position, with the digital display  16  showing a second number  22 B generated when the lock  10  is opened, which is used to identify that instance of the lock  10  being opened.  FIG. 4C  shows the lock  10  again closed, with a third number  22 C generated when the lock  10  is again closed, which is used to identify that instance of the lock  10  being closed.  
         [0035]     The random number generator is described as an integrated circuit. It should be understood that a random number can be generated by a variety of means. For instance, random numbers can be generated by the rotation of mechanical wheels or tumblers. Any method or means of generating a random number or identifier is incorporated into this invention.  
         [0036]     The apparatus and functionality as described above can be used in a variety of circumstances to determine if a lock  10  has been operated since the last authorized use of the lock  10 . One such circumstance is common to the shipping and carrier industries. In these industries, it is common for goods and inventory to be shipped significant distances in trucks, railcars, cargo ships, and the like. During shipping, goods are often secured within shipping containers. Between the origination point and the final destination, these containers may be passed through a chain of custody that includes local transporters, customs officials, distributors, consolidators, and warehousers. To discourage theft during the transportation from manufacturer to final destination, these containers are often locked with keyed padlocks. Although containers are locked, theft can still occur if the container is unlocked by an unauthorized person. Sometimes theft from shipping containers or of shipping containers is hard to detect. However, such unauthorized access can be detected through the use of the lock  10  as described above.  
         [0037]     A method of using the lock  10 , as described, is illustrated in  FIG. 6 . The lock  10  can be arranged such that each time the lock  10  on a container is closed, the switch or sensor senses the closing of the lock  10  and sends a signal to the integrated circuit to generate a new actuation identifier. Each time the lock  10  is opened and closed for an authorized purpose a new actuation identifier is generated. This number can be documented on the paperwork accompanying the container. Each time the container is reopened by an authorized user, the user can check the number  22  displayed by the digital display  16  against the actuation identifier documented in the paperwork to determine if there has been an unauthorized opening of the lock  10  since the last authorized user closed the lock  10 . If the displayed actuation identifier  22  matches the documented number, there has not been an unauthorized opening of the lock  10 . If the actuation identifiers differ, there is likely to have been an unauthorized opening of the lock  10 . This process can be repeated each time the lock  10  is opened by an authorized user from the origination of the shipment to the shipment&#39;s final destination.  
         [0038]     An additional security measure is the inclusion of a unique serial number  26  on the lock  10 , as best seen in  FIG. 3 . This allows the user to confirm that the specific lock being inspected matches the specific lock documented on the paperwork accompanying the container. Additional security measures include visual and audio alarms that indicate that the lock has been opened.  
         [0039]     While various aspects of the invention are described and illustrated herein as embodied in combination in the exemplary embodiments, these various aspects may be realized in many alternative embodiments not shown, either individually or in various combinations and sub-combinations thereof. Unless expressly excluded herein all such combinations and sub-combinations are intended to be within the scope of the present invention. Still further, while various alternative embodiments as to the various aspects and features of the invention, such as alternative materials, structures, configurations, methods, devices, and so on may be described herein, such descriptions are not intended to be a complete or exhaustive list of available alternative embodiments, whether presently known or later developed. Those skilled in the art may readily adopt one or more of the aspects, concepts or features of the invention into additional embodiments within the scope of the present invention even if such embodiments are not expressly disclosed herein. Additionally, even though some features, concepts or aspects of the invention may be described herein as being a preferred arrangement or method, such description is not intended to suggest that such feature is required or necessary unless expressly so stated. Still further, exemplary or representative values and ranges may be included to assist in understanding the present invention however; such values and ranges are not to be construed in a limiting sense and are intended to be critical values or ranges only if so expressly stated.

Summary:
A lock includes an actuation indicator that displays a unique actuation identifier. The actuation identifier changes with each actuation of the lock to provide an indication that the lock has been actuated.