Abstract:
A method of mounting a lock to a pick-up truck tailgate latching mechanism including the steps of locating targets for holes to be formed in a plastic bezel, the bezel carrying a handle for the tailgate, forming the holes in the plastic bezel, and securing the locking mechanism to the bezel via the formed holes.

Description:
RELATED APPLICATION(S) 
       [0001]    This application is a continuation of U.S. application Ser. No. 11/978,994, filed on Oct. 30, 2007 which claims the benefit of U.S. Provisional Application No. 60/855,300 filed Oct. 30, 2006. The entire teachings of the above application(s) are incorporated herein by reference. 
     
    
     BACKGROUND OF THE INVENTION 
       [0002]    A pickup truck typically has a cargo space secured by a tailgate. Pulling up on the tailgate handle releases a latching mechanism so that the tailgate may be swung down around its hinges to a horizontal position to provide access to the cargo area for loading and unloading. Generally, the hinges are constructed to permit lifting the tailgate off its hinges when it is in the horizontal position and removing it from the truck. 
         [0003]    The need to lock the tailgate is twofold. First, particularly when a camper top or a tonneau cover is mounted on the truck, it is desirable to be able to lock the tailgate to protect the gear stowed inside. Secondly, the tailgate itself is a desirable object for theft. 
         [0004]    A tailgate is generally constructed as a box section with the inner panel and the outer panel spaced apart by several inches. The handle and the latching mechanism are mounted between the two panels. To install the latching mechanism, truck manufacturers have taken two different approaches. One approach is to insert the mechanism from the inside, by providing a removable access door on the inside panel. The other, less expensive approach is to insert the mechanism from the outside through a handle aperture in the outside panel. In that instance, the handle aperture must be made big enough to accommodate the latching mechanism. To improve the appearance of the tailgate exterior, a snap-in plastic bezel may be mounted to the tailgate outer panel filling the void between the handle and the edges of an aperture. Some bezels have an aperture roughly equivalent in size to the handle of the tailgate latching mechanism such that if the tailgate were disassembled, the handle could be passed through the aperture. The aperture, in this configuration, is generally hidden from casual view by the handle when the tailgate is properly assembled. In an alternative configuration, the bezel may only have small apertures that accommodate a portion of the handle, such as arms that attach the handle to actuating mechanisms for the tailgate on the interior of the tailgate. 
         [0005]    One anti-theft device comprises a replacement bezel supporting a lock with a locking arm that prevents actuation of the tailgate handle and with a locking bolt that prevents removal of the bezel when the device is in the locked position. While this device affords a convenient and secure anti-theft solution, it is relatively expensive to manufacture. The replacement bezel has an intricate shape with retaining clips that has to be molded by precision injection molding tools. A truck manufacturer can amortize the cost of these tools over the entire number of trucks that are manufactured. However, an after-market manufacturer of the replacement bezel has to amortize the same tooling cost over a much smaller number of units sold, which adds significantly to the cost of those units. In addition, the cost of the prior anti-theft device is raised further by the need for both a locking arm and a locking bolt. 
       SUMMARY OF THE INVENTION 
       [0006]    The present invention comprises a locking mechanism mounted to the plastic bezel of a tailgate that requires only minor modification to the bezel when the bezel does not provide ready access to the interior components of the tailgate. 
         [0007]    In one embodiment of the invention comprises a method of mounting a lock to a tailgate comprising the steps of locating targets for holes to be drilled in the plastic bezel surrounding a tailgate handle, forming one or more holes at the targets, and securing a locking mechanism at an exterior portion of the bezel via the one or more holes. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0008]    The foregoing will be apparent from the following more particular description of example embodiments of the invention, as illustrated in the accompanying drawings in which like reference characters refer to the same parts throughout the different views. The drawings are not necessarily to scale, emphasis instead being placed upon illustrating embodiments of the present invention. 
           [0009]      FIG. 1A  shows a typical pick-up truck bed and a tailgate with two latches; 
           [0010]      FIG. 1B  shows the tailgate of  FIG. 1A  with the tailgate swung down to an open position; 
           [0011]      FIG. 1C  shows the tailgate of  FIG. 1A  with the tailgate swung to the side in an open position; 
           [0012]      FIG. 2A  shows a detail view of the exterior portion of a handle assembly; 
           [0013]      FIG. 2B  shows a detail view of the interior portion of a handle assembly; 
           [0014]      FIG. 3A  shows a method of using a template to locate a hole to be drilled in a first embodiment of a handle assembly; 
           [0015]      FIG. 3B  shows an exploded view of the handle assembly of  FIG. 3A  and a locking mechanism; 
           [0016]      FIG. 3C  shows the handle assembly and locking mechanism of  FIG. 3B  from an exterior perspective; 
           [0017]      FIG. 3D  shows a cross sectional view of the handle assembly and locking mechanism of  FIG. 3B ; 
           [0018]      FIG. 4A  shows a detail view of the interior portion of a second embodiment of a handle assembly; 
           [0019]      FIG. 4B  shows a method of using portions of the handle assembly to locate a hole to be drilled in the handle assembly of  FIG. 4A ; 
           [0020]      FIG. 4C  shows an exploded view of the handle assembly of  FIG. 4A  and a locking mechanism; 
           [0021]      FIG. 4D  shows a cross sectional view of the handle assembly and locking mechanism of  FIG. 4C ; 
           [0022]      FIG. 5A  shows an exploded view of a handle assembly and a locking mechanism according to a third embodiment; 
           [0023]      FIG. 5B  shows a cross sectional view of the handle assembly and locking mechanism of  FIG. 5A ; 
           [0024]      FIG. 6  shows an exploded view of a handle assembly and a locking mechanism according to a fourth embodiment; 
           [0025]      FIG. 7  shows an interior view of a tailgate latching mechanism and an interfering locking cam mechanism; and 
           [0026]      FIG. 8  shows an exploded view of a locking mechanism. 
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       [0027]    A description of example embodiments of the invention follows. 
         [0028]    In U.S. Pat. No. 6,427,502 (“the &#39;502 patent”), I disclosed a locking mechanism that includes a mounting bracket that passes through a large aperture in a bezel of a tailgate. The locking mechanism disclosed in that patent is generally seated immediately beneath the tailgate handle in a recess. The locking mechanism includes a cam that moves between a first position and a second position. In the first position, the cam interferes with the path of movement of the tailgate handle, preventing the handle from being pulled, effectively locking the tailgate. In the second position, the cam does not interfere with the path of movement of the tailgate handle, allowing the handle to be pulled. 
         [0029]    The locking mechanism disclosed in the &#39;502 patent does not address two issues. First, some tailgate bezels do not include the large aperture that would allow bracket mounting as taught in the &#39;502 patent. Second, some tailgates are now constructed to allow swinging in two directions: swinging down on a horizontal axis or swinging to the side on a vertical axis. These bi-directional tailgates often have two separate handles, each handle controlling the latching mechanism for one of the two types of movement. A single locking mechanism of the type disclosed in the &#39;502 patent cannot effectively lock such a tailgate. 
         [0030]    The locking mechanism disclosed herein may be mounted to a bezel without an adequately sized aperture for a bracket. Furthermore, this locking mechanism may be mounted to the bezel to allow the locking mechanism to create a moveable interference with a portion of the tailgate latching mechanism utilized in all directions of movement of the tailgate. 
         [0031]      FIG. 1A  shows a typically configured pick-up truck bed  100  with a cargo area  102 . The cargo area  102  is boxed in by a front wall  126 , two side walls  118 ,  120 , and a tailgate  104 .  FIG. 1A  shows two bezels  106 ,  110 , each bezel carrying a handle  108 ,  112  mounted to tailgate  104 .  FIG. 1B  shows a typical mounting and movement of a tailgate  104 , in which the tailgate is rotated in the direction of arrow  114  by hinge  122 . Handle  108 , when pulled, releases latches (not shown), freeing the tailgate to swing around hinge  122  in the direction of arrow  114 .  FIG. 1C  shows a second mounting and movement of a tailgate  104 , in which the tailgate is rotated in the direction of arrow  116  by hinge  124 . Handle  112 , when pulled, releases latches (not shown), freeing the tailgate to swing around hinge  124  in the direction of arrow  116 . A pick-up truck may be equipped with one or both of the latch/hinge configurations shown above. The exact placement of the handles  108 ,  112  are not important. 
         [0032]      FIG. 2A  shows an exemplary handle assembly  200  that would be mounted in the tailgate  104  of a pick-up truck. The handle assembly  200 , as shown in  FIG. 2A  includes an exterior portion of a bezel  204 , typically made of plastic, surrounding a handle  202 . The handle  202  is pivotally mounted to arm portions  214  of the handle assembly  200  with pins  210 . The handle  202  also has arms  208  that interact with the latching mechanism (not shown) inside the tailgate  104 . The exterior portion of the plastic bezel  204  includes a recess  206  providing access to grip the handle  202 . 
         [0033]      FIG. 2B  shows an opposite view of the exemplary handle assembly  200  of  FIG. 2A . The view in  FIG. 2B  shows an interior portion of the bezel  212  and clearly shows the arm portions  214  of the handle assembly  200 .  FIG. 2B  also shows bolts  216  screwed into bolt receptacles (not visible) located on the interior portion of the bezel  212 . The bolt receptacles are typically molded in the handle assembly  200 . When the handle assembly  200  is installed in a tailgate  104 , bolts  216  would also pass through an interior mounting (not shown) in the tailgate  104  to rigidly attach the handle assembly  200  to the tailgate  104 . 
         [0034]      FIGS. 3A-3D  show one method of attaching a locking mechanism  312  (shown in  FIGS. 3B-3D ) to a handle assembly  200 .  FIG. 3A  shows the interior portion of bezel  212 . Template  304  is attached to handle assembly  200  by bolts  216 . Template  304  is attached by temporarily removing bolts  216  so template  304  can be moved into place such that holes (not visible) in template  304  align with holes (not visible) located on the interior portion of the bezel  212 . Bolts  216  are then replaced, rigidly holding template  304  in place relative to the interior portion of the bezel  212 . Template  304  also could be rigidly held by pins, dowels, rivets, or screws instead of using bolts  216 . Note that when bolts  216  are removed from handle assembly  200 , the handle assembly  200  may be easily removed from tailgate  104 , which may make the method disclosed herein easier to perform. After template  304  is installed on the interior portion of the bezel  212 , a drill  300  and drill bit  302  are used to drill a hole (not visible) in the handle assembly  200  from the interior portion of the bezel  212  to the exterior portion of the bezel  204 . The drill bit  302  is positioned and guided during the drilling process by hole  306  located in template  304 . 
         [0035]    As illustrated in  FIG. 3B , after hole  308  is drilled in the handle assembly  200 , lock assembly  312  is mounted to the exterior portion of the bezel  204 , in recess  206  in this example. The lock assembly  312  is held in place by bolt  310 , which passes through hole  308  to interface with bolt receptacle  318 . Alternatively, the lock assembly  312  can be held in place by a rivet passing through hole  308  or by a threaded portion of the locking mechanism (not shown) that passes through hole  308  and tightening a nut onto the threads extending to the interior portion of the plastic bezel. Note that  FIG. 3B  shows template  304  being removed prior to the installation of lock assembly  312  and bolt  310 . Alternatively, template  304  could be left in place such that bolt  310  passes through template guide hole  306  and hole  308  in handle assembly  200 . 
         [0036]    Lock assembly  312 , in addition to bolt receptacle  318 , also has a lock cylinder  314  and a cam  316 . The lock cylinder  314 , in this example, has a square end portion, enabling the cam  316  to be properly rotationally positioned with respect to lock cylinder  314 . 
         [0037]      FIG. 3C  shows the handle assembly  200  and a view of the exterior portion of bezel  204  with lock assembly  312  installed. Lock assembly  312 , in this embodiment, is nestled within recess  206 . A key interface  320  is present on an exterior surface of lock assembly  312  for a user to insert a key (not shown) and turn the lock to engage cam  316  in either a locked position or an unlocked position. Lock assembly  312 , in this example, fills a portion of recess  206 , but still leaves room for access to handle  202 . 
         [0038]      FIG. 3D  shows the handle assembly  200  with installed lock assembly  312  in cross-section. For clarity, lock cylinder  314  is removed in  FIG. 3D  and replaced with a representation of its axis of rotation  322 . Cam  316  is shown in the “locked” position, wherein a portion of cam  316  interferes with the path of movement  324  of handle  202 . If someone tries to open the tailgate  104  by pulling handle  202 , cam  316  will prevent handle  202  from moving far enough for arm  208  to actuate the tailgate latching mechanism (not shown). 
         [0039]      FIGS. 4A-4D  show an alternative method of mounting a lock mechanism  312  to a handle assembly  400 .  FIG. 4A  shows the interior portion of the bezel  402  of the handle assembly  400 . The interior portion of the bezel  402  includes a raised cylindrical boss  404 , which surrounds a hole  406  extending through the boss  404 . The hole  406 , if extended to the exterior portion of the bezel  204 , would also be present in the recess area  206 . However, when the bezel is molded, the hole  406 , at the exterior end, is covered with plastic. When a user wishes to add a lock mechanism  312  to the handle assembly, a drill  300  and drill bit  302 , as shown in  FIG. 4B , are used to create hole  406 . Drill bit  302  is inserted into hole  406 . Hole  406  guides drill bit  302  to properly drill out the bezel material in recess  206 , making the hole continuous from the interior portion of the bezel  402  to the exterior portion of the bezel  202 . 
         [0040]    After the hole is formed, lock assembly  312  is mounted to the exterior portion of the bezel  204 , in recess  206 . Bolt  408  passes through hole  406  and interfaces with bolt receptacle  318  in the lock assembly as is shown in  FIG. 4C .  FIG. 4D  shows the handle assembly  400  with installed lock assembly  312  in cross-section. For clarity, lock cylinder  314  is removed in  FIG. 3D  and replaced with a representation of its axis of rotation  322 . Cam  316  is shown in the “locked” position, wherein a portion of cam  316  interferes with the path of movement  324  of handle  202 . If someone tries to open the tailgate  104  by pulling handle  202 , cam  316  will prevent handle  202  from moving far enough for arm  208  to actuate the tailgate latching mechanism (not shown). 
         [0041]    A further embodiment is shown in  FIGS. 5A and 5B .  FIG. 5A  shows the interior portion of the bezel  212  of handle assembly  200  of  FIG. 3B , except two holes  308 ,  502  have been drilled in the handle assembly  200 . If a template is used like the template  304  used in the embodiment of  FIGS. 3A-3D , then the template here (not shown) would have two holes for making holes  308  and  502 . Here, as in  FIG. 3B , bolt  310  passes through hole  308  and into bolt receptacle  318  of the lock mechanism  312 . However, in this embodiment, lock cylinder  314  is longer and, when installed into the handle assembly  200 , lock cylinder  314  extends through hole  502  such that cam  316  is located beyond the interior portion of the bezel  212 .  FIG. 5B  shows this embodiment in cross-section. Lock cylinder  314  is not shown, but its axis of rotation  504  is shown extending through the bezel at recess  206 . Cam  316  is shown beyond the interior portion of the bezel  212 . In this position, cam  316  does not interfere with the path of movement  324  of handle  202 . However, cam  316  may now interfere with other portions of the tailgate latching mechanism (not shown) that ultimately attach to arm  208  of handle  202 . This arrangement, wherein the cam  316  interferes with internal portions of the tailgate  104  latching mechanism (not shown) may be preferable for tailgates  104  such as that illustrated in  FIGS. 1A-1C , in which there are multiple handles  108 ,  112 , each handle  108 ,  112  actuating a portion of the latching mechanism (not shown) to cause the tailgate  104  to either swing down, as in  FIG. 1B , or swing to the side, as in  FIG. 1C . A person having ordinary skill in the art would understand that cam  316  could be shaped and positioned to interfere with the movement of latching mechanism (not shown) for both handles  108 ,  112 . A person having ordinary skill in the art would also understand that cam  316  may be installed on lock cylinder  314  after lock cylinder  314  is passed through hole  502 . 
         [0042]      FIG. 6  shows a further embodiment in which the lock assembly  600  is mounted on an exterior portion of the bezel  204  away from the recess  206  for the handle  202 . In this case, the lock shaft  314  and cam  316  have to penetrate the handle assembly  200  to reach past the interior portion of the bezel  212  to interact with the latching mechanism (not shown).  FIG. 6  shows holes  602  and  604  drilled in the handle assembly  200  to receive bolt  310  and lock shaft  314 , respectively. Like the embodiments in  FIGS. 5A-5B , when the lock assembly  600  is installed on the handle assembly  200 , the cam  316  will be positioned to interfere with portions of the tailgate latching mechanism (not shown). A person having ordinary skill in the art would understand that cam  316  could be shaped and positioned to interfere with the movement of latching mechanism (not shown) for both handles  108 ,  112 . A person having ordinary skill in the art would also understand that cam  316  may be installed on lock cylinder  314  after lock cylinder  314  is passed through hole  604 . 
         [0043]      FIG. 7  shows a locking mechanism for a dual mode hinge tailgate such as described in U.S. Pat. No. 6,938,941. Such tailgates can be opened either side ways or up and down. Two separate handles are provided for each mode of operation. A synchronizing linkage mechanism assures that the tailgate cannot be opened both ways simultaneously. 
         [0044]    The layout of my invention is shown in  FIG. 7  in a plan view. The linkage  1  that opens the tailgate horizontally is actuated by a rod  2  that connects to the tailgate handle. The linkage  4  that opens the tailgate sideways is actuated by a cable pull that connects to a second handle (not shown). According to my invention a Bolt  5  is mounted so that it pivots on rivet  6 . Bolt  5  has a tooth  7  and another tooth  8  which engage linkage  1  and linkage  4  respectively. When Bolt  5  is turned to the right it blocks linkages  1  and  4  from moving, thus locking the tailgate. A Spring  9  is arranged to provide an over center force that biases the Bolt  5  either to the right in the locked position, or when the Bolt  5  is turned a few degrees to the left, it biases the Bolt  5  to the unlocked position. 
         [0045]    Bolt  5  carries two lugs  11  and  10 . Lug  11  engages Actuator Bolt  17  with a slot  18  that provides some lost motion between the two. Electro mechanical Actuator  19  can pull the Actuator Bolt  17  to lock the Bolt  5 , or can push it to unlock the Bolt  5 , depending on the polarity of the applied voltage. Spring  20  returns the Actuator Bolt  17  to the neutral position when no voltage is applied to the Actuator  19 . 
         [0046]    Lug  1  engages Connecting Rod  12  with a slot  13  that also provides some lost motion between the two. The Crank  15  can pull the Connecting Rod  12  to also lock Bolt  5 , or can push it to also unlock Bolt  5 . Crank  15  attaches to the Lock Shaft (shown in detail in  FIG. 8 ) and can be turned manually 45 degrees in both directions by the Key of the Lock. 
         [0047]      FIG. 8  shows the mechanism by which the Shaft  43  is spring loaded to return to the neutral position by the Spring  47  after the key is released. Additionally, Detent Spring  45  and Ball  44  bias the Shaft in the neutral position. 
         [0048]    One feature of my invention is that the Tailgate can be locked and unlocked both electrically or manually by virtue of the lost motion afforded by the Slots  13  and  18  and the fact that both the Actuator and the Lock are spring loaded to return to the neutral position. Since both the Actuator Bolt  17  and the Connecting Rod  12  are spring loaded in the neutral position, either linkage can be actuated to lock or unlock the Bolt  5 . The advantage of this feature is that since both modes function independently, the tailgate can be operated manually in the case of battery failure, or conversely, electrically if the key is misplaced. 
         [0049]    The teachings of all patents, published applications and references cited herein are incorporated by reference in their entirety. 
         [0050]    While this invention has been particularly shown and described with references to example embodiments thereof, it will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the scope of the invention encompassed by the appended claims.