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FIELD OF INVENTION 
     The present invention relates generally to security systems and in particular security systems for portable equipment, specifically expensive portable equipment such as computers. 
     BACKGROUND OF THE INVENTION 
     The present invention relates to anti-theft devices for deterring the theft of small but expensive pieces of equipment. Many devices have been developed to help prevent the theft of computers and other electronic equipment. Since many systems that need security include several items, such as a computer and a monitor and a printer, such security devices often utilize a cable which connects each of the components to each other and/or to a relatively immovable object such as a desk. 
     Most computer manufacturers incorporate some attachment method for security devices. This practice began on some of the earliest Macintosh computer models, where they provided several different sized security slots designed to accept ‘snap-in’ security attachments that would then allow a security cable to pass through that attachment. Other manufacturers provided reversible brackets built into the computer chassis that allowed you to remove the computer cover and turn the bracket around for use with a security cable. Even others had nothing but regular chassis screws that were secured by use of “screw-on” fasteners that security cables passed through to prevent unscrewing the fastener and thus secure the equipment. All this has evolved over the years to the point where most manufacturers of desktop computers provide a bracket already protruding from the back of the chassis with a hole that a security cable can pass through. 
     On smaller devices like laptops where a protruding bracket is undesirable, manufacturers have adopted a small security slot in the exterior wall. Many different security devices have been developed over the years to fit into this security slot. The majority of those devices rely on two or more tiny opposing hooks to maintain a locked position in the security slot, or one slot engagement member with one or two pins also entering the slot to maintain the locked position of the slot engagement member, the pins preventing rotation of the entire housing to prevent moving the slot engagement member to align with the slot and pull back out of the security slot. 
     One of the biggest drawbacks of the existing devices is that all the laptop manufacturers design this security slot in vastly different sizes and the wall through which the hole, opening aperture or slot passes is made of a wide range of thicknesses. The existing security devices must be designed to fit the thickest of these walls, and thus they “flop around loosely” on most laptops. This creates a perception of insecurity that has plagued the industry since its inception. The present inventor has been in the industry for almost 15 years and dealt with many different laptop security devices and has had to deal with this major complaint from customers ever since computer manufacturers started putting existing slots into the computers. 
     The second major drawback of existing devices for laptop security is that previous thinking has limited the inventions to a slot engagement member providing security and a second engagement member or pin entering the security slot to maintain the locked position. This cuts down the raw physical size of the engagement member to a fraction of the size of the available security slot, making the device much easier to break, or snap off, at the point of security. The present inventor has seen customer tests of existing products that work with the small security slot in laptops fail by breaking year after year. 
     Overriding the considerations of laptop security are computer security needs in general. For many years, there have been countless security devices for computers that were model-specific, such as special sized enclosures or straps, or cables with special fasteners for the exact computer they were meant to protect. Many times the user did not realize that the security device they purchased would not work on other computers until they replaced the computer with the next model. With today&#39;s constant upgrades, this type of security device is simply inefficient and costly. 
     SUMMARY OF THE INVENTION 
     The present invention provides a cable lock that addresses all of the above weaknesses of cable locks currently provided for computer and electronic equipment, while also providing a cable lock for use in other industries because of its universal nature. It addresses the major problem of perceived insecurity of the loose, floppy cable locks by ratcheting tightly against the equipment to be secured and is perceived as a “solid” security measure. The present invention also overcomes the weaknesses of previous designs that required multiple hooks or pins to maintain a locked position in existing laptop security slots by providing for a hook that is the full peripheral dimension of the hole that it passes through, maximizing the level of security. The present invention also addresses the problem of existing locking cables in the market that fit into existing security slots on laptops, but the locking mechanism is permanently attached to the end of the cable and cannot be removed to allow the cable to thread through fasteners on multiple pieces of equipment. The present invention is the first truly universal security device that is intended to work on any technology device, whether it has a security slot or not. It doubles as a laptop security cable or a desktop security cable, adapting as the user updates their equipment. 
     The basic design of the hook requires the hook to be taller than it is wide, so that entry into a round hole with a diameter greater than the width of the hook can occur, and when the hook is then moved to an angle more perpendicular to the external wall of the equipment, it cannot be removed from the round hole when the hook is at that angle as long as the diameter of the hole is less than the height of the hook. Thus the diameter of any round hole must be greater than the width of the hook and less than the height of the hook. It is foreseen that a standard hook size will be sold with instructions to drill a standard hole size to work with that hook. However, it is expected that as equipment is recognized as having built-in holes that do not work with standard hooks, cables with different sized hooks will be sold. It is also expected that future cables will have a replaceable or adjustable hook design to fit any size hole. 
     Another major improvement over existing devices is the ability of the present invention to secure multiple pieces of equipment with one lock. The housing of the cable lock is intended to be removed, allowing the cable to pass through multiple pieces of equipment or security fasteners (common when securing desktop computers). The housing can then be replaced on the cable to be secured independently (as a standard desktop cable lock is secured), or to fit into a vent slot, drilled hole, or security slot as might be required for laptop security or flat screen monitors. 
     The following drawings are for the purpose of illustration only and are not intended to define the limits of the invention. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Advantages of the present invention will be apparent from the following detailed description of exemplary embodiments thereof, which description should be considered in conjunction with the accompanying drawings, in which: 
         FIG. 1  is a perspective view of a first embodiment of the present invention of the housing assembly clamped onto the cable; 
         FIG. 2  is a perspective view of a first embodiment of the present invention attached to another object such as a desk by way of a loop on one end of the cable. The invention is shown in one of its “multiple-use” configurations having passed through holes on security fasteners (built-in or add-on brackets) on one or more pieces of equipment, with the housing assembly of  FIG. 1  locked onto the end of the cable without the hook being used to secure a final piece of equipment. 
         FIG. 3  is a perspective view similar to  FIG. 2  but the invention is shown in a second of its “multiple-use” configurations having passed through holes on security fasteners (built-in or add-on brackets) on one or more pieces of equipment, with the last piece of equipment being secured by use of the hook hooking into a slot or hole (either built-in or added-on) as shown in  FIG. 8 . 
         FIG. 4  is a perspective view similar to  FIG. 2  but the invention is shown in a third of its “multiple-use” configurations having been secured on its loop end to a another object (in this case a ceiling beam) and only used to secure a single piece of equipment (in this case an overhead projector) by use of the hook hooking into a slot or hole (either built-in or added-on) as shown in  FIG. 8 . 
         FIG. 5  is a perspective view similar to  FIG. 2  but the invention is shown in a fourth of its “multiple-use” configurations having been secured on its loop end to a another object (in this case a pole) and only used to secure a single piece of equipment (in this case a toolbox) but also being used to keep that equipment closed (see  FIG. 7 ) by use of the hook hooking through two aligned holes (either built-in or added-on), one hole in the cover, and one in the main case. 
         FIG. 6A  is a side view of the hook in the first embodiment of the present invention as it enters the hole or slot in the external wall of the equipment at a second angle to the external wall. 
         FIG. 6B  is a side view of the hook in the first embodiment of the present invention after it has been hooked into the hole and moved to the first angle to the external wall, an angle in which the hook cannot be pulled out. 
         FIG. 6C  is a side view of the hook in the position of the first angle of  FIG. 6B  with the housing of the first embodiment moved into a position that prevents movement of the hook back to the second angle, thus preventing removal of the hook from the exterior wall. 
         FIG. 7  is similar to  FIG. 6C  except that it shows the method of  FIG. 5  of keeping a cover closed by hooking the hook through aligned apertures in the walls of the cover and the case. 
         FIG. 8  is a cross-sectional end view of one possible clamping means inside the housing of the present invention to clamp onto the cable, biased in the clamped position with the spring. It also shows one possible design of the locking mechanism with the base of a lock cylinder in between the top of the clamp to separate and release the clamp when the key is turned. It is envisioned that the clamping means does not have to be biased in the clamped position, as it can be moved from clamped to unclamped by use of a locking mechanism that can leave it in either position. 
         FIG. 9  is an exploded perspective view of the preferred embodiment of  FIG. 1   
         FIG. 10A  is a perspective view of one preferred embodiment of the hook end of the cable, with grooves at specific locations to lock the housing onto multiple locations of the cable. Some of the grooves allow for ratcheting in only one direction without the key, the end groove will not allow movement in either direction without the key. 
         FIG. 10B  is a perspective view of another preferred embodiment of the hook end of the cable, intended for use with a clamp that locks directly onto the cable jacket, normally a type of rubber. Depending on the design of the clamp teeth, the housing assembly of  FIG. 1  would either slide only one direction without the key, or not slide at all without the key. 
         FIG. 11A  is a perspective view of a second preferred embodiment of the present invention, while 
         FIG. 11B  is an exploded perspective view of the internal components of  FIG. 11A . In this embodiment, the hook is not at the end of the cable, but integrated into the housing as a retractable hook. This embodiment would still be attached to a hole or slot in an external wall in the same method of  FIGS. 6 . The hook would be biased in the extended position by use of a spring, retracted into the housing by use of levers or gears, and would only move in the direction of retraction without unlocking the locking mechanism to allow extension. 
         FIG. 12  is a perspective view of a security fastener, that works similar to  FIG. 11 , but uses a security cable or padlock shackle passed transversely through the housing to maintain or release the hook retraction instead of an integrated locking mechanism. 
         FIG. 13  is a perspective view of a housing having a clamshell design, which enables the security cable to be inserted through the housing the hooking mechanism is too large to fit through the transverse hole of the housing. 
     
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     The object of the present invention is a method of attaching a cable  12  to a hole or slot  19  in an external wall  20  ( FIG. 6 ) of the portable equipment to be secured by hooking the hook  1  at the distal end of the cable  12  into that hole or slot  19  and maintaining the hooked position by locking a housing assembly  2  onto the cable  12 , close enough to the external wall  20  to prevent unhooking the hook  1 . The housing assembly  2  is locked or unlocked from the cable  12  by use of a locking mechanism  3 , in this illustration a keyed lock cylinder. The illustrated housing assembly  2  has a lengthwise hole  4  through which the cable  12  can be passed. 
     The preferred design of the present invention relies on the height  10  of the hook  1  from the top  6  to the bottom  7  being greater than the width  9  between the sides  8 . This allows the present invention to be secured into any hole  19  that has a round diameter less than the hook&#39;s height  10  and greater than the hook&#39;s width  9 . It also allows the present invention to be secured into any hole  19  into which it fits that has a square or rectangular shape where its short side is shorter than the hook&#39;s height  10 . Thus the invention can work with any existing hole or slot  19  in and external wall  20 , such as vent holes or security holes, whether those holes  19  are round, square, or rectangular, or one can be drilled if none exist. 
     Thus very few, or even one, standard sized hooks  1  can fit a very wide range of built-in or added-on holes  19  in exterior walls  20 . It is also envisioned that replaceable or ‘height adjustable’ hooks  1  will be added to the product as it is called for. 
     One major improvement of the invention over existing cable locks, especially for use in the technology industry, is that it works in multiple configurations as the user&#39;s needs change with rapid changes in technology. Several of these configurations are shown in  FIGS. 2 ,  3 ,  4  and  5 . It can be used to secure single or multiple pieces of equipment, whether the pieces of equipment  14  have built-in or add-on security fasteners  15 , or whether the pieces of equipment  14  have built-in or add-on holes or slots  19  that the hook  1  can attach to. 
     In general, the cable  12  is attached on its loop  11  at the proximal end to another object  13  such as a desk, beam, or pole by inserting the distal end through the loop  11  of the proximal end and tightening the cable  12  around the object  13 . When securing multiple pieces of equipment  14 , the housing assembly  2  would be temporarily removed from the cable  12  and the cable  12  would be passed through existing or added-on security fasteners  15  on the equipment to be secured  14 . Added-on security fasteners  15  are well known in the art and can be glue-on, screw-on, or hook-on types. A type of added-on security fastener that uses the technology of the current invention is shown in  FIG. 12 . 
     The housing assembly  16  can then be locked back onto the cable  12  to be secured independently as in  FIG. 2 , or hooked into one last piece of equipment  17  as shown in  FIG. 3 . It can also be used to secure a single piece of equipment  17  like a laptop or projector as shown in  FIG. 4 . It can also be used to secure a piece of equipment like a toolbox  18  or equipment  17  (such as a CPU) from being opened in addition to securing it in place if the hook  1  is hooked simultaneously through aligned holes in the cover and case of the equipment to be secured (see  FIG. 7 ). 
     It is recognized that many different methods of locking or clamping the housing assembly  2  onto the cable  12  are well known in the art, but one preferred method is illustrated in  FIG. 8  by use of a gate or clamp  21  pivoting around a pivot point  22  and biased in the clamped or locked position by use of a spring  23  and unlocked or released from the clamped position by turning the key in locking mechanism  3  causing the base  25  of the locking mechanism  3  to separate the gate  21 . 
       FIG. 9  shows a preferred optional gate spring  24  similar in function to  23  and a spring-loaded mounting pin  26  used to assemble the locking mechanism  3  into the housing  5 . Teeth  27  that point in one direction are located on the interior surface of the gate  21  to allow the housing assembly  2  to slide freely in one direction on the cable  12  and bite into the cable  12  in the other direction, requiring use of the key to unlock the gate  21  to move the housing assembly  2  in the other direction. 
     In one preferred embodiment of the cable  12  ( FIG. 10A ), small grooves  28  cut into the distal end of the cable  12  that correspond in shape and size to the teeth  27  on the gate  21  allow the position of the housing assembly  2  relative to the cable  12  to be locked on in a tighter and more precise location if desired than locking onto the rubber jacket of the cable  12 . A special, deeper groove  29  is also provided that doesn&#39;t allow the housing assembly  2  to move in either direction, and locks the housing assembly  2  onto the cable  12  in an exact position when used in the configuration of  FIG. 2  so that it is more aesthetically pleasing because the hook  1  does not protrude outside the housing assembly  2  when it is not in use. 
     Another preferred embodiment of the current invention does not have a hook  32  at the end of the cable  40 . Instead the hook  32  is integral with the housing assembly  38 . The basic operating principle of the invention is the same and the hook assembly  31  is biased towards an extended position from the housing assembly  38  by use of a spring  42 . This extended position allows for hooking of the hook  32  into the hole or slot  19  in the external wall  20  of the protected equipment. As shown in  FIG. 6  the hook is moved from a second angle to a first angle, and then the hook assembly  31  is retracted into the housing assembly  38  by pulling the lever  30  which is part of the hook assembly  31  towards the back end  50  of the housing assembly  38  along the guide slot  49 . 
     As the hook assembly  31  is retracted into the housing assembly  38 , it is ratcheted into incrementally more retracted positions by the hook  34  on the locking bar  35  riding up the sloped side of each groove  33  on the hook assembly  31  and being pushed down into a locked position on the next groove  33  by the force of the spring  41 . It continues to ratchet into each groove  33  incrementally until the housing assembly  38  is tight against the exterior wall  20  to prevent unhooking of the hook  32  from the protected equipment. 
     The illustrated locking mechanism, lock cylinder  39 , is made up of the lock core  44  the lower washer  45  the upper washer  46  and the lock shell  47  and is all held together with a retaining pin  48  and is well known in the industry. It is envisioned that many types of locking mechanisms, such as keyed and combination lock cylinders can be used in the present embodiment. 
     Turning the key (not shown but as known in the art) in the lock cylinder  39 , forces the base  43  of the lock core  44  to rotate into the upper side  37  of the locking bar  35 , pivoting it around pivot point  36  and lifting hook  34  out of the grooves  33  and allowing the hook assembly  31  to extend back into its biased position and allowing the hook  32  to be removed from the protected equipment. The security cable  40  may be permanently or removably attached to the housing assembly  38  and attached at the other end to another object. The security cable  40  is also optional as the housing assembly  38  could be used simply to connect two external walls  20  together or keep a cover closed as shown in  FIG. 7 . 
     The hook assembly  31  can also be held in the retracted position by use of a padlock or security cable  52  instead of a locking mechanism by passing through a transverse aperture  53  of the security fastener  51  and not allowing removal of the security fastener  51  from the external wall.  20 . Finally, in instances where a large hooking mechanism is required, a clamshell design may be used to construct the housing assembly  2  in the event the hooking mechanism is too large to fit through the transverse hole of said housing. 
     While several embodiments of the present invention have been illustrated by way of example, it is apparent that further embodiments could be developed within the spirit and scope of the present invention. However, it is to be expressly understood that such modifications and adaptations are within the spirit and scope of the present invention, as set forth in the following claims.

Summary:
A locking cable device, which generally inhibits the theft of portable and more specifically inhibits the theft of expensive, electronic devices such as computers, laptops, and projectors. The security device works by use of a hook that hooks through an opening in an outside wall of the equipment to be secured. The hole can be an existing hole in the outside wall of the equipment, either round, square, or rectangular, such as a vent slot or security slot. A user may also add the opening by merely drilling an aperture or slot, sized appropriately for the corresponding hook on the security device. The hooked position is maintained by use of a housing locked on to the cable, close enough to the equipment being secured that the hook cannot be moved to an angle necessary for removal.