CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application is entitled to the benefit of Canadian Patent Application 2,231,428 filed on Jun. 30, 2000. 
     BACKGROUND 
     1. Field of the Invention 
     This invention relates to firearms, specifically to a trigger lock for a firearm to prevent the trigger device from movement. 
     2. Description of the Prior Art 
     Unauthorized or inadvertent discharge of a firearm is a problem that injures or kills many people. This problem is particularly acute and distressing in the case of children who play with their parent&#39;s firearm. The prior art reveals many attempts to alleviate this problem by selectively disabling the gun by locking blocking devices to obstruct the barrel of the gun or by locking trigger blocking or guarding devices to the trigger guard. 
     One such prior art device is described in U.S. Pat. No. 5,910,002 issued to Hunter on Jun. 8, 1999 and entitled “Gun Trigger Safety Device”. Hunter describes a trigger-blocking plug that conforms to the space behind the trigger to prevent the weapon from firing. However, the Hunter device cannot be securely locked to the weapon to disable it and therefore it is unsuitable for securing safe a weapon in a home or for long periods of time. 
     Another attempt at a plug-type tigger safety device is described in U.S. Pat. No. 5,724,760 issued to Langner on Mar. 10, 1998 and entitled “Trigger Safety Device”. Langer discloses a design that permits a trigger blocking device to be locked to the weapon. Langner&#39;s device includes a horizontal extension from one side of the trigger-blocking plug that includes a hole at right angles to the plug&#39;s axis and through which a small padlock may be engaged. Since the padlock shackle is disposed at right angles to the plug, it engages a side of the trigger guard and trigger to prevent unauthorized removal of the plug from behind the trigger. However, the padlock shackle may be used to twist and break the extension and thereby free the device from the firearm. As well, Langner teaches a two-piece system comprising a lock and a separate trigger blocking device leaving the smaller trigger blocking device vulnerable to misplacement and loss. Additionally, the separate padlock dangles freely from the firearm and therefore may scratch the finish of the gun. 
     SUMMARY 
     In accordance with my present invention there is provided a trigger lock for a firearm having a barrel, a frame, a handle and a trigger depending from the bottom of the frame and disposed in front of the handle. The trigger lock comprises a trigger lock body comprising a trigger blocking portion for placement behind the trigger to prevent rearward movement of the trigger to a firing position. Also included is a flange adjacent to and integral with the trigger blocking portion for positioning in an abutting relationship with one side of the trigger guard to prevent lateral and twisting movement of the trigger blocking portion. Also included is a padlock having a locking body with a top surface and a U-shaped shackle. The shackle has a curved head from which depends a first leg lockably disengagable from the top surface of the locking body and a second leg pivotally and permanently engaged to the top surface of the locking body. Means for removably mounting the guard body in a cooperative frictional engagement on to the free leg of the shackle is also provided. This permits the guard body and shackle first leg combination to be positioned horizontally behind the trigger as a single piece so that when the trigger blocking portion is behind the trigger and the padlock is closed, the top surface of the padlock creates an abutment abutting against the trigger guard opposite the first flange preventing movement of the trigger blocking portion. 
     Objects and Advantages 
     Accordingly, several objects and advantages of my invention are: 
     a. to provide a trigger lock that overcomes the deficiencies observed in the prior art; 
     b. to provide a trigger lock that permits the locked gun to be safely stored in a loaded condition; 
     c. to provide a trigger lock that can be quickly fitted to and removed from the gun; 
     d. to provide a trigger lock that may be easily adapted to fit a wide variety of existing firearms; 
     e. to provide a trigger lock that is difficult for unauthorized persons to remove; 
     f. to provide a simplified gun trigger lock that is inexpensive to manufacture using off the shelf padlocks; and, 
     g. to provide a trigger lock that does not scratch the gun to which it is affixed. 
     A further object and advantage of my invention is to provide a trigger lock that can be mounted to the shackle of a commercial padlock without further modification to the padlock and create a single piece device that is difficult to misplace or loose. 
     Still further objects and advantages of my invention will become apparent from a consideration of the ensuing description and drawings. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 illustrates in perspective view a padlock suitable for use as part of my invention in the closed position. 
     FIG. 2 illustrates the same padlock in another perspective view for use as part of my invention in the open position. 
     FIG. 3 illustrates a typical trigger guard in side view that my invention may be adapted to. 
     FIG. 4 illustrates in perspective view one embodiment of the locking body of my invention. 
     FIG. 5 illustrates the same embodiment of the locking body of my invention shown in FIG. 4 from a different perspective. 
     FIG. 6 illustrates one embodiment of my invention mounting in a sliding engagement with a shackle of a padlock suitable for use in my invention. 
     FIG. 7 illustrates one embodiment of my invention mounted on a shackle of a closed padlock and placed behind the trigger of a firearm. 
     FIG. 8 illustrates the same embodiment as that in FIG. 7 from a different perspective. 
     FIG. 9 illustrates another embodiment of the locking body of my invention. 
     FIG. 10 illustrates yet another embodiment of the locking body of my invention. 
     FIG. 11 illustrates the same embodiment of FIG. 10 from a different perspective. 
    
    
     DETAILED DESCRIPTION 
     One advantage of my invention is that it is used in combination with a suitable commercially available padlock without having to make any modifications to the padlock. One example of padlocks that work well with my invention are those manufactured under the trademark MASTER™. These padlocks are known to be very strong and tamper resistant and therefore well suited for securing a firearm. 
     FIG.  1  and FIG. 2 illustrates padlock  10  suitable for use with my trigger lock in the closed position and open position respectively. Padlock  10  has a top surface  8  and is comprised of locking body  12 , which engages both ends of shackle  14  within a locking socket  18  and, swivel socket  16 . Shackle  14  is typically hardened steel rod formed into a “U” shaped shackle comprised of a semi-circular head  20  and a first leg  22  and a second leg  24  depending from the head. Means for locking and unlocking the shackle from the locking body is shown in FIG. 2 as key  26  inserted into key lock  28 . A padlock with a combination locking means may also be used. 
     When the padlock is opened, first leg  24  is disengaged from the locking socket  18  of the locking body  12  it is free to pivot about locking socket  16  in which second leg  24  is permanently secured. 
     FIG. 3 illustrates a common trigger guard  54  as might be found on a variety of typical firearms. It is to be understood that my invention is easily adaptable to almost any manufacture of handgun having a trigger  48  and trigger guard  54  similar to that illustrated here. The trigger guard  54  surrounds trigger  48 . The trigger  48  has a front surface  50 , a rear surface  52 , a first side  41  and a second side  43 . The trigger guard has a first side  56  and a second side  58 . Void  60  is created between the rear surface of the trigger  52  and the trigger guard  54 . Typically the width of the trigger is slightly less than the width of the trigger guard. 
     FIG.  4  and FIG. 5 illustrate one embodiment of the trigger lock body  70  of my invention from different perspectives. Locking body  70  comprises a trigger blocking portion  72  for placement behind the trigger  48  of a firearm to prevent rearward movement of the trigger  48  to a firing position. The trigger blocking portion  72  has a head  73  (shown as hash marked portion) and a body  75  and a width at least equal to the trigger but generally slightly wider than the width of the trigger. The trigger blocking portion  72  is configured to substantially fill the void  60  between the rear of the trigger  48  and the trigger guard  54  to prevent required movement of the trigger to a firing position. A flange  74  is placed adjacent to and integral with the trigger blocking portion  72  for positioning in an abutting relationship with side  56  of the trigger guard  54  thereby preventing lateral and twisting movement of the trigger blocking portion  72 . Stop member  76  is integral to the trigger blocking portion  72  and raised from the side  78  of the trigger blocking portion and is adapted to engage in an abutting relationship the side  43  of the trigger  48 . Stop  76  assists flange  74  to prevent lateral movement  73  of the locking body  70  within the trigger guard  54 . Alternatively, stop member  76  may be removed thereby leaving flange  74  to absorb twisting forces placed on the trigger lock body. 
     Still referring to FIGS. 4 and 5 the trigger blocking portion  72  comprises, a first side  78 , a second side  80 , a front surface  82 , a top surface  84 , a bottom surface  86  and a rear surface  88 . Front surface  82  is concave in shape and adapted to generally agree with the rearward convex-shaped surface of the trigger  48 . Rear surface  88  is convex in shape and adapted to generally agree with the concave-shaped trigger guard  54 . Top surface  84  is generally rounded and adapted to extend upwards towards the top of the trigger guard  54  so that it substantially fills void  60  and prevents rearward movement of the trigger  48  to a firing position. Bottom surface  86  is generally curved in a convex shape and tapered to a truncation  85  that extends downwards and forwards to the bottom of the trigger  48  to further fill void  60 . 
     Still referring to FIGS. 4 and 5, flange portion  74  comprises a first side  90 , a second side  92 , a front surface  94 , a rear surface  96 , a top surface  98  and a bottom surface  100 . At least 50% of first side  92  of flange  74  is attached to and integral with side  78  of the trigger blocking portion  72 . The bottom portion  93  (shown in the hash lines) of flange  74  extends below the bottom of the trigger guard  54  to inhibit lateral and twist movement of the trigger blocking portion  72 . Flange  74  is substantially rectangular in shape. 
     Shoulder portions  102  and  104  extend from the head portion (shown as  73  in the hashed area) of the trigger blocking portion  72 . They are contiguous with and integral to each side of the head  73  of trigger blocking portion  72  respectively and have the same top surface profile as the trigger blocking portion. The bottom surface  106  and  107  of shoulder  102  and  104  respectively are flat and parallel to the flat bottom surface  100  of the flange portion  74 . 
     Referring now to FIGS. 4,  5  and  6  together there is illustrated the manner in which the locking body  70  of my invention is removably and slidably mounted to the shackle  14  of a padlock  10  to advantageously form a single piece trigger lock. This greatly reduces the chances of losing the locking body when it is removed from the firearm. FIGS. 4,  5  and  6  illustrate that the locking body  70  has means for removable and slidingly mounting itself to leg  22  of the U-shaped shackle  14  of a padlock  10 . The means comprises an aperture  110  through the flange portion  74  and the trigger blocking portion  72  of the guard body  70 . The aperture  110  is sized to receive  24  of shackle  14  in frictional sliding engagement by using hand force. Once guard body  70  is placed onto the shackle leg  22  the locking tip  112  of the leg  22  is exposed beneath the shoulder portion  102  of the body  70  for lockable engagement with socket  18  in the locking body  12  of the padlock  10 . Also shown in FIGS. 4,  5  and  6  is groove  114  within the surface  90  of flange  74 . Groove  114  is adapted in shape receive the head  20  of the U-shaped shackle  14 . Groove  114  is sufficiently deep to enclose the head of the U-shaped shackle so that the top surface of the head  20  of the shackle  14  is substantially flush with the outside side surface of the flange  90 . 
     Referring now to FIG.  7  and FIG. 8, there is shown one embodiment of my invention locking body  70  mounted to the shackle  14  of a padlock  10  and the shackle  14  and locking body  70  combination placed behind the trigger  48  within trigger guard  54 . The blocking portion  72  is placed in sliding engagement behind the rear surface  52  of the trigger  48  so that rearward movement of the trigger to a firing position is prevented. Trigger stop  76  abuts against the side  43  of trigger  48  to prevent the locking body from sliding too far into the trigger guard. Flange  74  abuts against the side  56  of the trigger guard and also prevents any lateral movement of the locking body within the trigger guard. The stop  76  and the flange  74  also prevent any twisting movement of the locking body within the trigger guard  54 . It is important to note that one advantage of my invention is to place the shackle of the lock in combination with the locking body horizontally behind the trigger instead of hanging the padlock vertically beside trigger guard. This configuration prevents twisting of the lock and breaking of the locking body. It is virtually impossible to remove the combined shackle and locking body without having to cut the trigger guard away from the frame of the firearm or cut the shackle of the lock. It also prevents scratching of the firearm. 
     Shoulder portions  102  and  104  of the locking body  70  extend from both sides of the blocking portion  72  and are integral to the blocking portion. The shoulders to provide additional resistance to any attempt to twist the locking body from the behind the trigger. There is at least one shoulder although there may be two. 
     Still referring to FIG.  7  and FIG. 8, there is shown my invention mounted behind the trigger  48  with the padlock  10  closed and locked. The top surface  8  of the locking body  12  of the padlock  10  abuts against the opposite side  58  of the trigger guard  54  and forms an opposing abutment to flange  74 . In this manner the body  70  is sandwiched between the top surface of the padlock locking body  8  abutting against side  58  and flange  74  abutting against side  56 . 
     The embodiment of my invention shown in FIGS. 4 and 5 will accommodate many types of trigger and trigger guard configurations. However, some trigger and trigger guard configurations will demand that an inventory of trigger lock bodies by kept with each one configured to exactly fit a different make of firearm. For that reason, additional embodiments of my invention are described below. 
     Referring now to FIGS. 3 and 9 there is shown an alternate embodiment  120  of the locking body of my invention suited to firearms having a small void  60  behind trigger  48 . 
     The locking body  120  of this embodiment of my invention comprises a trigger blocking portion  122  for placement behind the trigger  48  to prevent rearward movement of the trigger to a firing position. The trigger blocking portion is configured to substantially fill the void  60  between the rear of the trigger  52  and the trigger guard  54 . A flange portion  124  is placed adjacent to and integral with the trigger blocking portion  122  for positioning in an abutting relationship with side  56  of the trigger guard  54  thereby preventing lateral and twisting movement of the trigger blocking portion  122 . 
     Still referring to FIG. 9 the trigger blocking portion  122  comprises, a first side  126 , a second side  128 , a front surface  129 , a top surface  130 , a bottom surface  132  and a rear surface  131 . Front surface  129  and rear surface  131  are both generally concave so that blocking portion  122  is generally ovular in shape with an axis  134  that is disposed at an angle  137  of less than 90 degrees to the horizontal axis  136  of flange  124 . Blocking portion  122  is adapted to substantially fill the void behind trigger  48 . 
     Referring to FIG. 9, flange portion  124  comprises a first side  140 , a second side  142 , a front surface  144 , a rear surface  146 , a top surface  150  and a bottom surface  148 . Side  128  of the blocking portion  122  is fixed to and integral with side  140  of flange  124 . The bottom surface  148  is adapted to extend below the bottom of the trigger guard  54  to inhibit lateral movement of the trigger blocking portion  122 . Flange  124  is substantially rectangular in shape. 
     Referring to FIGS. 6 and 9, there is illustrated the manner in which the locking body  120  of my invention is mounted to the shackle  14  of a padlock  10  to advantageously form a single piece trigger lock. The means comprises an aperture  152  through the flange  124  and the trigger blocking portion  122  of the guard body  120 . The aperture  150  is sized to receive leg  22  of shackle  14  in frictional sliding engagement by using hand force. Also shown in FIG. 9 is groove  154  within flange  124 . Groove  154  is adapted in shape receive the head  20  of the U-shaped shackle  14 . The groove is sufficiently deep to enclose the head of the U-shaped shackle so that the top surface of the head of the shackle is substantially flush with the outside side surface of the flange  124 . Body  120  is mounted to a padlock shackle and placed behind the trigger of a firearm substantially as shown in FIG.  6 . 
     Referring now to FIGS. 10 and 11 there is shown yet another embodiment of my invention. The locking body  180  comprises a trigger blocking portion  182  for placement behind the trigger of a firearm to prevent rearward movement of the trigger to a firing position. The trigger blocking portion may have a width equal to the trigger or slightly wider than the width of the trigger. The trigger blocking portion is configured to substantially fill the void  60  between the rear of the trigger  52  and the trigger guard  54 . A flange  184  is placed adjacent to and integral with the trigger blocking portion  182  for positioning in an abutting relationship with side  56  of trigger guard  54  thereby preventing lateral and twisting movement of the trigger blocking portion. 
     Still referring to FIGS. 10 and 11 the trigger blocking portion  182  comprises, a side  186 , a front surface  190 , a top surface  194 , a bottom surface  196  and a rear surface  192 . Front surface  190  is concave in shape and adapted to generally agree with the rearward convex-shaped surface of the trigger  48 . Rear surface  192  is convex in shape and adapted to generally agree with the concave-shaped trigger guard  54 . Top surface  194  is rounded and tapered and adapted to extend upwards towards the top of the trigger guard  54  so that the body  180  substantially fills void  60 . Bottom surface  196  is rounded and tapered and adapted to extend downwards towards the bottom of the trigger  48  again to fill void  60 . 
     Still referring to FIGS. 10 and 11, flange portion  184  comprises a first side  200 , a second side  202 , a front surface  204 , a rear surface  206 , a top surface  208  and a bottom surface  210 . Side  202  is partially contiguous and integral with the trigger blocking portion  182 . Flange  184  extends substantially below the bottom of the trigger guard  54  to inhibit lateral movement of the trigger blocking portion. Top surface  208  of flange  184  has a profile identical to that of the top surface  182  of the trigger blocking portion and a back surface  206  that is substantially planar. Bottom surface  210  of the flange is flat. 
     Shoulder portion  212  is contiguous with and integral to the first side  186  of the trigger blocking portion  182  and has generally semi-circular shape having a top surface  214  profile identical to the top surface profile  194  of the trigger blocking portion  182  and a bottom surface  216  that is flat and parallel with the flat bottom surface  210  of the flange portion. 
     Still referring to FIGS. 10 and 11 there is shown aperture  220  through the flange portion  184  and the trigger blocking portion  182  of the guard body  180  for mounting the body to the shackle of a padlock. Aperture  220  is sized to receive leg  22  of shackle  14  in frictional sliding engagement by using hand force. Once body  180  is placed onto the shackle leg  22  the locking tip  82  of the leg  22  is exposed beneath the shoulder portion  212  of the body  180  for lockable engagement with the locking body  12  of the padlock  10 . Also shown is groove  222  within the surface  200  of the flange portion  184  of the guard body  180 . The groove  222  is adapted in shape receive the head  20  of the U-shaped shackle  14 . The groove is sufficiently deep to enclose the head of the U-shaped shackle so that the top surface of the head of the shackle is flush with the outside side surface of the flange. 
     The body  180  mounts to a padlock shackle and behind the trigger  48  of a firearm as shown in FIG.  6 . 
     Although this description contains much specificity, these should not be construed as limiting the scope of the invention by merely providing illustrations of some of the embodiment of the invention. Thus the scope of the invention should be determined by the appended claims and their legal equivalents rather than by the examples given.
A trigger lock for a firearm lock is disclosed comprising a trigger lock body having a trigger blocking portion. The trigger blocking portion has a head and a body for placement behind the trigger to prevent rearward movement of the trigger to a firing position. The trigger lock body includes a flange adjacent to and integral with the trigger blocking portion for positioning in an abutting relationship with the trigger guard thereby preventing lateral and twisting movement of the trigger blocking portion once placed behind the trigger. There is provided at least one shoulder portion extending laterally from the head of the body beyond the corresponding side of the trigger guard when the body is placed behind the trigger to resisting twisting motion. The trigger lock body mounts to a shackle of a padlock so that the body and padlock shackle to which it is mounted forms a unitary trigger guard for insertion behind the trigger.