You are an expert at summarizing long articles. Proceed to summarize the following text:

You are an expert at summarizing long articles. Proceed to summarize the following text: 
BACKGROUND OF THE INVENTION  
       [0001]    1. Field of the Invention 
         [0002]    The invention relates, generally, to locks, and more specifically, it relates to a multi-shackle lock for locking luggage that can be subjected to inspection and then be relocked. 
         [0003]    2. Description of the Related Art 
         [0004]    Combination operated padlocks of the type typically used to secure luggage during travel and transport are well known. U.S. Pat. No. 6,877,345 teaches combination operated luggage padlocks that also may be operated by a key to facilitate inspection of the contents of luggage. Specifically, the combination and key operated luggage padlocks and the like have a resettable indicator to advise the owner of the luggage that a lock on the bag has been opened presumably by a key for inspection. The opened luggage indicator preferably can be reset only by the owner after he/she has opened the lock by entering a respective combination. 
         [0005]    When the U.S. Transportation Security Administration (TSA) took over the handling of airport security in accordance with the Homeland Security Act, the intensified effort made by federal employees to inspect locked bags of airline passengers often resulted in the destruction of luggage padlocks when the shackles thereof were severed to permit inspection of the luggage contents. The destruction of luggage padlocks unfortunately leaves inspected bags unlocked, with their contents subject to pilfer and theft during travel and transport. 
         [0006]    The need of travelers for post-inspection luggage security while also accommodating the need of government employees to quickly and easily open and inspect selected and suspect bags, lead to the development of override keys for nondestructively opening the luggage. 
         [0007]    Combination operated luggage padlocks that have built-in key override features were now introduced. Such padlocks may be purchased by consumers for locking their luggage; and, if their locked bags are inspected by government personnel, the padlocks will be opened for baggage inspection using keys that are made available to government inspectors (but not to the owners of the padlocks), and then will be relocked by the inspectors. Bags inspected and relocked in this manner will have their contents secured by the same combination operated padlocks that were installed on the bags by the owners thereof. 
         [0008]    Padlocks that can be operated by combination and by key are not new. Combination padlocks have been used for many years on gym lockers in schools, with coaches and principals having keys that can open these padlocks should lockers need to be inspected, or should a padlock be snapped closed on an incorrect locker by mistake or by prank. It also is known to provide combination padlocks with keys so that their owners may elect whether to open the locks by entry of a combination, or by using a key. 
         [0009]    It is not completely new to provide padlocks with some form of indicator. For example, padlocks that are not of the type that can be opened both by combination and by key have been provided with indicators that are intended to prevent accidental resetting of the combinations of the locks, or that are intended to reflect when the padlocks are incompletely or improperly relocked after being opened. However, prior proposals relating to padlocks of the type that can be opened by combination or by key have not taught or suggested the provision of indicators constructed to advise the owners of the locks that the luggage on which the padlocks are installed has been inspected by opening the padlocks with a key. 
       SUMMARY OF THE INVENTION  
       [0010]    It is accordingly an object of the invention to provide a multi-shackle lock and method of using the multi-shackle lock, which overcomes the herein-mentioned disadvantages of the heretofore-known devices and methods of this general type, which allows the lock to be opened and relocked without the need of a special key. 
         [0011]    With the foregoing and other objects in view there is provided, in accordance with the invention, a lock. The lock is formed of a housing, a locking mechanism supported by the housing, and three shackles being lockable by the locking mechanism or the housing. 
         [0012]    As noted above, after Sep. 11, 2001 the Transportation Security Administration (TSA) took over the handling of airport security and inspection of luggage. In order to inspect the luggage, the baggage locks had to be cut and the luggage was left unsecured as it traveled throughout the transportation system. TSA then requested that customers not lock their luggage in order to allow inspection without damaging the luggage and the locks. 
         [0013]    In an attempt to provide the customers a way of securing their bags while still allowing TSA to carry out their inspection, several companies configured locks with both a key lock and a combination lock and many of these locks have an indicator for identifying if the lock was opened for inspection. Special master keys were then given to the TSA for opening all the locks. 
         [0014]    However, these prior art locks simply do not provide the security they advertise. It is a false sense of security for the following few and simple reasons. There are thousands of TSA agents throughout our country, all of which have access to the keys that open the locks. It is only a matter of time, if it has not already occurred that these keys will fall into the hands of what we call the luggage bandit. In many cases the locks have the second key operation option but have no measure for letting the customer know that someone has opened the lock. This is equivalent to having a home alarm system and giving a second alarm security code to thousands of people you do not know. The second reason is that 90% of all luggage used today is of the zipper closure type. On this type of luggage you can simply pull the zipper closure with the locked lock to one extreme of the luggage zipper. Using a sharp object as simple as a ball point pen you can open the zipper and pilfer the luggage. Once finished you can simply pull the closed lock and secured zipper closure to the opposite extreme. This re-zips and closes the zipper 99%. To the untrained eye the luggage shows no signs of having been tampered with until you have arrived to your home or vacation destination. In addition the above-mentioned keys are only available to USA agents and are not available on an international level. Therefore, when traveling internationally, the current so called TSA luggage locks will be cut as before and the luggage will be left unsecured throughout the rest of its journey. 
         [0015]    In accordance with an added feature of the invention, the housing includes a main housing and a shackle housing releasably holding one of the three shackles for replacing the one shackle. The main housing houses the locking mechanism and the shackle housing supports two of the three shackles. The shackle housing is releasably connected to the main housing for replacing the shackle housing containing the two shackles with a new shackle housing contain two new shackles. 
         [0016]    In accordance with another feature of the invention, the three shackles include a luggage securing shackle made from metal, plastic, cabling, wiring or a combination of at least two of metal, cabling and wiring. 
         [0017]    Ideally, the housing has a serial number for at least one of identification, tracking, travel insurance and travel assistance service. Alternatively or additionally, a tracking device is supported by the housing and the lock can be tracked world wide. 
         [0018]    In a further embodiment of the invention, each of the three shackles is color coded for identifying the shackle function. The three shackles include a first shackle locked in place by the locking mechanism, a second shackle locked in place by the locking mechanism, and a third shackle locking to the shackle housing. 
         [0019]    Preferably, the second shackle is releasable secured to the shackle housing, and the third shackle is permanently fixed to the shackle housing. 
         [0020]    In accordance with another feature of the invention, the shackle housing has a locking key for releasably securing the shackle housing to the main housing. The main housing has a housing side wall with a recess formed           locking key can be inserted through the recess and held in place by the housing side wall. The shack           rotatable about the locking key for replacing the second shackle. The shackle housing has a wall and the locking key has a cutout formed therein next to the wall for fixing around the housing side wall. 
         [0021]    In accordance with another feature of the invention, the main housing and the shackle housing define a recess therebetween. The shackle housing has an abutment extending out from the recess, and the third shackle secures to the abutment when inserted in the recess. Uniquely, the third shackle is released from the abutment when the shackle housing is rotated. 
         [0022]    With the foregoing and other objects in view there further is provided, in accordance with the invention, a method of operating a luggage lock. The method includes providing a multi-shackle lock having a main housing, a shackle housing, and three shackles, including a first shackle, a second shackle and a third shackle. The first shackle is secured to an anchor part of a piece of luggage having a zipper. The second shackle is secured to a zipper pull-tab for preventing an opening of the piece of luggage. The third shackle is left unlocked. 
         [0023]    In accordance with a further mode of the invention, the second shackle is cut resulting in a cut second shackle. The piece of luggage is opened for inspection and then relocked by securing the third shackle to the zipper pull tab. After this, the cut second shackle is removed and a new second shackle is inserted putting the lock back to a as new condition. 
         [0024]    Alternatively, the shackle housing containing the cut second shackle and the third shackle is removed from the main housing and a new shackle housing containing a new second shackle and a new third shackle is reconnected to the main housing. 
         [0025]    In order to perform the replacement, the shackle housing is rotated about the main housing for getting access to the cut second shackle. The cut second shackle is removed and the new second shackle is inserted. The shackle housing is rotated back and the shackle housing is secured in place by inserting the new second shackle into the main housing. 
         [0026]    Other characteristic features of the invention are set forth in the appended claims. 
         [0027]    Although the invention is illustrated and described herein as embodied in a multi-shackle lock and a method of using the multi-shackle lock, it is nevertheless not intended to be limited to the details shown, since various modifications and structural changes may be made therein without departing from the spirit of the invention and within the scope and range of equivalents of the claims. 
         [0028]    The construction of the invention, however, together with additional objects and advantages thereof will be best understood from the following description of specific embodiments when read in connection with the accompanying drawings. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWING 
         [0029]      FIG. 1  is a diagrammatic, perspective view of a multi-shackle lock according to the invention; 
           [0030]      FIG. 2  is a diagrammatic, exploded perspective view of the multi-shackle lock; 
           [0031]      FIG. 3  is a diagrammatic, top plan view of a shackle housing; 
           [0032]      FIG. 4  is a perspective view of the multi-shackle lock with a top cover removed; 
           [0033]      FIG. 5  is a perspective view of the multi-shackle lock with a shackle housing in a rotated position and a bottom cover removed; and 
           [0034]      FIG. 6  is a diagrammatic, longitudinal view of the shackle housing showing only the openings for a second shackle. 
       
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS  
       [0035]    Referring now to the figures of the drawing in detail and first, particularly, to  FIG. 1  thereof, there is shown a lock  20  being a combination operated lock, a key operated lock or both a combination and key operated lock  20  all with a multi-shackle locking system. 
         [0036]    The multi-shackle lock  20  can be operated by a preset combination, a key, or both the preset combination and the key. The operation of the lock  20  is similar to locks currently on the market for use on luggage, sport bags or equipment cases. In  FIG. 1 , the lock  20  is provided with a single combination lock mechanism  2  having three combination thumb wheels  4  for operating the combination lock mechanism  2 . Of course the number of thumb wheels  4  can vary between 2-6. A single key lock or two locks being a key and combination lock are also possible, however  FIG. 1  only shows a single combination lock  2  without the need for a key. 
         [0037]    As best shown in  FIG. 2 , the multi-shackle lock  20  has a housing formed of two connectable housing parts  8 ,  12  and a removable shackle housing  9 . 
         [0038]    The lock  20  features a unique multi shackle system that allows the lock  20  to be secured to a piece of luggage, more particularly to a luggage handle. What is further specific and unique about the lock  20  is that it can only be operated by the owner of the lock  20  because only the single combination lock mechanism  2  is present. However, the lock  20  still allows TSA and all international security agents to inspect the luggage and return it to a locked condition by providing additional unlocked shackles. A first shackle  7  is used to secure the lock  20  to a luggage handle or similar anchor part on a piece of luggage. The use of the luggage handle eliminates the possibility of moving the lock  20  to the zipper extreme, opening the luggage and using the closed lock to reseal the zipper. A second shackle  10  is used by the owner to close or secure the luggage opening, e.g. lock the zipper tab (slider) to the luggage handle. A third shackle  11  is left in the open position so that security agents can cut open the lock (e.g. the second shackle  10 ) as they have done for many years and re-close the lock  20  using the third shackle  11  after the luggage has been inspected. 
         [0039]    The multi-shackle lock  20  further has the capability of replacing the shackle housing  9 . The shackle housing  9  with the second and third shackles  10 ,  11  is supplied as a disposable part. Once the second shackle  10  has been cut by TSA, the owner can open the lock  20 , replace the shackle housing  9  containing new second and third shackles  10 ,  11  and return the lock  20  to an as new condition. The shackle housing  9  has a locking key  21  for engaging on an inside wall  22  of the upper and lower housings  8 ,  12 . The locking key  21  is initially positioned at a 90 degrees angle so that the locking key  21  slides through a recesses  23 . As the shackle housing  9  is rotated from the 90 degrees angle back to the normal, the locking key  21  engages the inside wall  22  and secures the shackle housing  9 . As best seen in  FIG. 3 , there is a space  24  between the locking key  21  and a wall of the shackle housing  9  for allowing the connection between the shackle housing  9  and the upper and lower housing parts  8 ,  12 . 
         [0040]    The second shackle  10  has a notch  17  for engaging into a locking projection  18  of the combination lock mechanism  2 . When the locking projection  18  engages in the notch  17  of the second shackle  10 , the second shackle  10  secures the shackle housing  9  to the lock housing  8 ,  12 , see  FIG. 4 . When the second shackle  10  is cut the, the second shackle  10  can be removed. After the second shackle is removed, the shackle housing  9  can be rotated and physically pulled out from the housing  8 ,  12  because the locking key  21  can now slip out of the recess  23 . In this way the whole shackle housing  9  can be rotated, removed and then replaced as described above.  FIG. 5  shows the shackle housing  9  in a rotated position for removal or insertion. 
         [0041]    Alternatively, the shackle housing  9  need only be partially rotated in which access to a first hole  25  is provided. As noted, the shackle housing  9  is partially rotated, the cut second shackle  10  is removed and a replacement shackle  10  is threaded through the first hole  25  and the shackle housing  9  is closed again. 
         [0042]    At this point it needs to be emphasized that when replacing either the shackle housing  9  or the second shackle  10 , the housing parts  8 ,  12  remain secured to each other at all times and are not separated from each other as shown in the figures. 
         [0043]      FIG. 6  shows a top, sectional view of the shackle housing  9  showing only the openings for the second shackle  10 . The second shackle  10  has a winged end  26  for fitting in a recess  27  at the end of the first hole  25  and therefore securing the second shackle  10  to the shackle housing  9 . The second shackle  10  has a mid-section  29  formed from wiring or cabling and is bent around and reinserted into a second hole  28 . In this manner, a supply of second shackles  10  is sold with the lock for multiple reuses. 
         [0044]    Returning to  FIG. 2 , a first end  30  of the third shackle  11  is fixedly secured in a third hole  31  of the shackle housing  9 . A second end  34  of the third shackle  11  has a notch  32  (see  FIG. 5 ) for locking with an abutment  33  (see  FIG. 2 ) when the second end  34  is inserted into recess  35  formed between the top cover  8  and the shackle housing  9 . Of course the locking mechanism can be reversed with an abutment formed on the second end  34  of the third shackle  11  for latching with a cutout formed in the recess  35 . As can best be seen in  FIG. 5 , when the shackle housing  9  is rotated, the second end  34  of the third shackle  11  is automatically released and ready for reuse. 
         [0045]    The multi-shackle lock  20  addresses all the fore mentioned issues relating to the prior art locks alone or the locks with a special TSA key. By securing the lock  20  to the luggage or luggage handle you eliminate the possibility of having the lock being used to reseal the zipper. With this method the zipper can&#39;t be re-closed and therefore will most likely never be opened. By providing the additional shackles  10 ,  11  the customer can lock his\her luggage and use it both nationally and internationally. The customer simply locks the luggage, the international agent simply cuts it open for inspection and re-locks it with the additional shackle. 
         [0046]    Ideally, the locks will all be the same colors, such as a bright orange with separate colors to identify the different shackle of the system. Therefore the lock of the instant application requires no intervention or cooperation with TSA or other agencies (e.g. send them master keys). 
         [0047]    In addition the multi-shackle lock  20  may be provided with additional security features such as a serial number  15  or tracking bar code and/or tracking device  16 . The tracking device  16  may be an active or passive radio frequency identifier (RFID), a global positioning satellite (GPS) reader or other electronic/visual tracking device. 
         [0048]    In this manner, a luggage tracking service and a travel assistance service can be easily incorporated or used with the lock. Ideally, the information relating to the location of the lock  20  can be provided on a web site under each specific customer account. The customer logs on to our web sit using his or her user name and password. The site shows a page that displays all the locks owned by that specific customer and where they are. In addition, the website allows reorders for new shackles. 
         [0049]    As noted above, the multi-shackle lock can be used universally (e.g. internationally) where any airport inspection agency can use the lock and at the same time, the owner will know that his luggage has been inspected.

Summary:
A lock for luggage, sports gear or any type of travel enclosure which can be operated by a key, combination or both, which has more than one shackle. The lock has one shackle that secures the lock to the luggage or luggage handle while the other shackle secures the luggage closure or zipper. An addition shackle is provided for the purpose of re-closing the luggage after the luggage is inspected by an international airport security agent. If the luggage is inspected, the inspector simply cuts the zipper shackle and re-secures the luggage using the additional or third shackle. A disposable shackle system allows the customer to replace the cut shackle and return the lock to its original condition for reuse.