Patent Abstract:
A firearm includes a frame and a firing mechanism having a sear (e.g., configured for controlled release of a firing pin) and a trigger bar for actuating the sear. The trigger bar is disengageable from the sear. A locking mechanism is attached to the frame and can be actuated (e.g., by using a key) to selectively disengage the trigger bar from the sear. The locking mechanism may include a pin extending through the frame and axially rotatable in place. A first end of the pin is accessible from the exterior of the frame for key actuation, and a second end of the pin is positioned proximate to the trigger bar in the interior of the frame. The second end of the pin is provided with a cam surface for laterally shifting the trigger bar out of engagement from the sear when the pin is axially rotated using a key.

Full Description:
This application claims the benefit of the following U.S. Provisional Applications: Ser. No. 60/639,187; Ser. No. 60/638,594; Ser. No. 60/638,753; Ser. No. 60/638,593; Ser. No. 60/638,746; Ser. No. 60/638,592; Ser. No. 60/638,751; and Ser. No. 60/638,752, all filed Dec. 22, 2004, and all hereby incorporated by reference herein in their entireties. 

   TECHNICAL FIELD 
   The present invention relates generally to devices for locking firearms and, more particularly, to key locks for semiautomatic pistols or handguns. 
   BACKGROUND OF THE INVENTION 
   Various devices have been used to prevent the discharge of firearms. Such devices have included trigger locks or similar mechanisms that, when incorporated into the firearm, deter the firing of the firearm by incapacitating the trigger. Trigger locks typically consist of two mating elements that are mounted and locked together over or around the trigger guard and trigger of the firearm, thereby blocking access to and/or movement of the trigger. 
   Other devices used to prevent the discharge of firearms employ an integral mechanical combination lock to secure the firearm. These devices typically employ mechanical keypads with small numbered buttons or dials that are used to enter the numbered code to unlock the device and remove it from the firearm. 
   Although the aforesaid devices can be effective, they generally work in a manner where certain firearm components, e.g., the trigger, are blocked or restricted. Thus, if the device is bypassed and the trigger accessed, it may be possible to discharge the firearm. What is needed is a locking device that, when enabled, prevents the firing of a firearm even if the trigger is actuated. 
   SUMMARY OF THE INVENTION 
   A firearm incorporating an embodiment of the locking mechanism of the present invention includes a frame and a firing mechanism. The firing mechanism has a sear (e.g., configured for controlled release of a firing pin) and a trigger bar for actuating the sear. The trigger bar is disengageable from the sear. The locking mechanism is attached to the frame and can be actuated using a key to selectively disengage the trigger bar from the sear. 
   In another embodiment, the locking mechanism includes an axially rotatable pin. A first end of the pin is accessible from the exterior of the firearm for key actuation, and a second end of the pin is positioned proximate to the trigger bar in the interior of the frame. The second end of the pin is provided with a cam surface for laterally shifting the trigger bar out of engagement from the sear when the pin is axially rotated. For example, the second end of the pin may include a face surface perpendicular to the axis of the pin, a stepped land integral therewith, and an arcuate, ramp-like surface extending between the face and land. In a first axial position of the pin, the trigger bar lies against the face surface. When the pin is rotated in place, the arcuate, ramp-like portion of the pin rotates into contact with the trigger bar, gradually laterally shifting the trigger bar until it comes to rest against the land, out of engagement with the sear. 
   One advantage of the locking apparatus of the present invention is that a handgun incorporating such a locking apparatus blocks the operation of the trigger. The operation of the trigger is blocked because the mechanical link between the trigger assembly and the fire control mechanism (namely, the trigger bar) is disengaged. 
   Another advantage is that such a locking apparatus is made difficult or impossible to defeat by smashing the exposed end of the pin. In particular, because the operable portion of the locking apparatus (e.g., the cammed surface that causes the disengagement of the trigger bar from the sear) is housed within the frame of the handgun, an attempted defeat of the apparatus will likely result in damage being caused to the portion at which the key engages the pin to lock or unlock the handgun. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The present invention will be better understood from reading the following description of non-limiting embodiments, with reference to the attached drawings, wherein below: 
       FIG. 1  is a simplified schematic side view of a semiautomatic pistol; 
       FIG. 2  is a simplified schematic side view of the pistol of  FIG. 1  shown with the slide moved to a rearward position on the pistol frame; 
       FIG. 3  is a simplified schematic perspective view of a fire control mechanism portion of the pistol of  FIG. 1 ; 
       FIG. 4  is a simplified schematic perspective view of a key lock according to an embodiment of the present invention; 
       FIG. 5  is a simplified schematic perspective view of the key lock of  FIG. 4  illustrating a sleeve disposed over the key lock; 
       FIGS. 6A to 6E  are exemplary schematic views of various configurations for an irregular shape of the key lock; 
       FIG. 7  is a simplified schematic perspective view of the sear assembly illustrating operable communication between the key lock and a trigger bar of the firing mechanism; and 
       FIG. 8 ,  FIG. 9 , and  FIG. 10  are simplified schematic perspective views of the key lock of the present invention as it inter-engages with the trigger bar. 
   

   DETAILED DESCRIPTION 
   Referring to  FIGS. 1 and 2 , one exemplary embodiment of a semiautomatic pistol or handgun which may incorporate the locking apparatus of the present invention is shown generally at  10  and is hereinafter referred to as “firearm  10 .” The firearm  10  comprises a frame  12 , a slide  14 , and a fire control mechanism  18  (see  FIG. 2 ) that operates via actuation of a trigger  22 . The frame  12  is fabricated of a high-impact polymer material, metal, a combination of polymer and metal, or other suitable materials. The slide  14  houses a barrel  16  in the forward end thereof. The barrel  16  is cooperatively linked with the slide  14  and, together with the slide  14 , defines a longitudinal firing axis  17 . A rearward end  19  of the barrel  16  is adapted for receiving an ammunition cartridge. 
   The slide  14  is fitted to opposingly-positioned rails  28  on the frame  12  to effect the reciprocal movement of the slide  14  along the longitudinal firing axis  17 . The rails  28  extend along the underside of the slide  14  in the longitudinal direction and are cooperative with the frame  12  to allow the cycling of the slide  14  between forward (battery) and rearward (retired) positions. The slide  14 , which is defined by a slide frame  30 , further includes a breech face  32  and an extractor port  34 . The breech face  32  is engagable with the rearward end  19  of the barrel  16  to form a firing chamber when the slide  14  is disposed forwardly on the frame  12  (see  FIG. 1 ). An ejection mechanism provides for the ejection of a cartridge casing  40  in a direction indicated by an arrow  42  upon firing the firearm  10  or manually cycling the slide  14 . 
   Referring now to  FIG. 3 , the fire control mechanism is shown at  18 . The fire control mechanism  18  is of a striker-type firing pin configuration, and comprises a striker-type firing pin  23  having a firing pin portion  20  and a depending leg  21 . The fire control mechanism further comprises a sear assembly  26  and a trigger assembly  42 . The sear assembly  26  has a pivotally-mounted sear  50  that selectively engages the firing pin  23 . The trigger assembly  42 , which functions to actuate the sear  50 , includes the trigger  22  and a trigger bar  31  pivotally connected to the trigger  22  via a pin  34 . The trigger bar  31  connects the trigger  22  and the sear assembly  26 . A trigger bar extension  33  extends from the trigger bar structure into a channel  29  of the sear assembly  26 . The trigger  22  may be of unitary construction, as shown, or of a multiple-piece articulated construction. When the trigger  22  is actuated by being pressed in a rearward direction, the trigger  22  pivots about a pin  38  and transmits movement to the trigger bar  31  via the pin  34 . The trigger bar  31  is thereby moved in a rearward direction substantially parallel to the longitudinal firing axis such that the trigger bar extension  33  correspondingly translates in the channel  29 . The connection of the trigger bar  31  to the trigger  22  and sear assembly  26  is such that the trigger bar  31  can be laterally displaced away from the sear assembly  26  when pressure is exerted on the trigger bar  31  and/or trigger bar extension  33 , e.g., in a direction that is perpendicular to the direction in which the longitudinal firing axis extends. 
   Referring now to  FIGS. 4 and 5 , a key lock (locking mechanism means) of the present invention is shown generally at  60 . The key lock  60  includes a selectively rotatable element mounted on the frame of the handgun to effect the selective engagement of the trigger bar  31  with the sear  50 . A positive force is used to rotate the selectively rotatable element about an axis  61 . In one embodiment, the selectively rotatable element is a pin  70 . When the handgun is in an operational mode (e.g., when the key lock  60  is disengaged or in the “unlocked” position), a cooperating sloped surface  75  on the trigger bar engages the sear  50 . Longitudinal movement of the trigger bar  31  in a rearward direction causes the sear  50  to rotate and eventually disengage from the depending leg  21  of the firing pin  23 . This unblocks the firing pin, allowing the firing pin to translate in a forward direction under the urging of a decompressing firing pin spring, and to engage a cartridge in a firing chamber to fire the handgun. When the handgun is “locked” (e.g., when the key lock  60  is engaged), the pin  70  urges the trigger bar laterally within the frame of the handgun such that the cooperating surface  75  on the trigger bar is disengaged from the sear  50 . Thus, because the mechanical link between the trigger bar and the sear is interrupted, the operation of the trigger has no effect on the movement of the sear  50 . 
   A sleeve  62  ( FIG. 5 ) may be mounted over a first end  64  ( FIG. 4 ) of the pin  70  to receive a key  63 , the rotation of which provides for the rotation of the pin  70 . The first end  64  of the pin  70  is contoured to receive the key. For example, in the embodiment depicted, the first end  64  is contoured to have an irregular shape that corresponds to an irregularly shaped receiving surface on the key. The irregular shape of the first end  64  and the corresponding receiving surface of the key are closely machined such that the surfaces inter-engage to have little tolerance. The irregular shape is preferably configured such that a key having receiving surfaces cannot be readily fabricated by an unauthorized user of the handgun for the purpose of defeating the key lock  60 . 
   The irregular shape contoured into the first end  64  may comprise at least one groove, indentation, hole, slot, or other channel  80  that extends from an end surface of the first end  64  longitudinally into the surface. Referring now to  FIGS. 6A through 6E , various configurations of the irregular shape of the key lock are shown. The channel  80  formed in the first end  64  of the pin  70  may be continuous as shown in  FIG. 6A , or it may be discontinuous and include at least two terminal end points as shown in  FIG. 6B . In the embodiment shown in  FIG. 6C , a plurality of short channels  80  may be formed in the first end  64  to receive corresponding projections on a key. In another embodiment shown in  FIG. 6D , two or more continuous channels  80  may be nested. In still another embodiment shown in  FIG. 6E , combinations of continuous, discontinuous, and nested channels  80  may be formed or otherwise disposed into the end surface of the first end  64  of the pin  70 , such channels  80  being dimensioned to receive the corresponding projections of a key. 
   The pin  70  is positioned through the frame and the sear assembly  26  such that the pin  70  is rotatable about the axis  61 . Referring now to  FIG. 7 , a second end  72  of the pin has a cammed surface  74  that extends axially in the direction of the axis of the pin. When the key lock  60  is disengaged or is in the “unlocked” position and the handgun is operational, the cammed surface  74  at the second end  72  is positioned under the (non-displaced) trigger bar extension  33  and a face surface  35  of the second end  72  of the pin engages a side surface of the trigger bar extension  33 . 
   The cammed surface  74  is defined by a protrusion extending longitudinally from the face surface  35  and in a direction that corresponds with the axis (axis  61  shown in  FIG. 4 ). Preferably, outermost surfaces of the protrusion are continuous with the outer surfaces of the body of the pin  70  such that a transition from the body of the pin  70  to the protrusion is smooth. 
   Referring now to  FIGS. 8-10 , the protrusion has a first end and a second end. The first end is defined by an edge  82  that extends parallel to the axis  61 . The second end terminates at the face surface  35  in an edge that extends along the face surface  35  radially outward from the axis  61 . The protrusion itself is chamfered such that the edge  82  and the edge at which the second end terminates are connected by the cammed surface  74 , which comprises a continuous arcuate surface that provides a gradual incline from the edge  82  to the face surface  35  along which an object (namely, the trigger bar extension  33 ) can be cammed to provide movement in a direction parallel to the axis  61 . The cammed surface  74  can also be thought of as comprising a stepped land parallel to the face surface  35  (see  FIG. 7 ), with an arcuate ramp portion extending between the face surface  35  and land. 
   As stated above, the trigger bar  31  is laterally displaceable in a direction that is substantially perpendicular to the longitudinal firing axis  17 , as indicated by arrow C in  FIG. 9 . As the key lock  60  is operated, the pin  70  axially rotates and the edge  82  is urged against the undersurface of the trigger bar extension  33 . As the edge  82  is urged against the trigger bar extension  33 , the cammed surface  74  displaces the trigger bar extension  33  (and the trigger bar  31 ) laterally within the channel  29  and pushes the trigger bar extension  33  out of registration with the cooperating surface on the sear  50 . More specifically, when the key lock  60  is operated, the pin  70 , upon overcoming the bias of an optional spring component  76 , axially rotates. As the pin  70  axially rotates, the trigger bar extension  33  is cammed by the curved surface  74 , which thereby forces the trigger bar  31  in the direction indicated by arrow C ( FIG. 9 ). When the trigger bar extension  33  reaches the end of the pin  70  ( FIG. 10 ), the trigger bar  31  is fully displaced and the trigger bar extension  33  has been pushed out of registration with the sear  50 , thereby effecting a “locked” or disabled position. Once locked or disabled, the sear  50  is prevented from rotating via movement of the trigger (and the associated movement of the trigger bar) to operate the handgun. 
   It is only when the key lock  60  is rotated by the user to overcome the pressure of the spring  76  that the trigger bar extension  33  is allowed to return into engagement with the cooperative surface on the sear  50 , thereby rendering the handgun operational. 
   In one embodiment of the present invention, as described above, a semiautomatic handgun comprises a frame, a reciprocating slide mounted on the frame, and a barrel mounted inside the slide. The slide comprises an elongated structure having a forward end for housing the barrel and a rearward end that houses a firing pin mechanism that cooperates with a trigger assembly and a fire control mechanism mounted in the frame. The frame includes a key lock mounted thereon. The key lock includes a pin that is mounted transversely to a longitudinal firing axis of the handgun. The pin is selectively rotatable about an axis thereof using a key. Rotation of the pin using the key causes a surface on the pin to urge a trigger bar of the trigger assembly out of contact with a sear of the fire control mechanism, thereby preventing the firing of the handgun by the actuation of the trigger. 
   In another embodiment of the present invention, as described above, a key lock for a handgun includes a pin mounted in the frame of the handgun transverse to a longitudinal firing axis of the handgun. The pin has a first end and a second end. The first end has a surface at which a key having a corresponding mating surface can be presented to rotate the pin in an axial direction. The second end has a cammed surface that engages a surface of a trigger bar of the handgun. The cammed surface is configured such that upon rotation of the pin in the axial direction using the key, the trigger bar is urged out of registration with a sear of a fire control mechanism to prevent firing of the handgun. 
   As should be appreciated, the locking mechanism could be oriented in other manners than as shown in the figures, e.g., coincident to a plane defined by the firearm frame as opposed to lying perpendicular thereto (in other words, accessible from the top or bottom of the handgun), while still effectuating a camming action upon the trigger bar. 
   Although this invention has been shown and described with respect to the detailed embodiments thereof, it will be understood by those of skill in the art that various changes may be made and equivalents may be substituted for elements thereof without departing from the scope of the invention. In addition, modifications may be made to adapt a particular situation or material to the teachings of the invention without departing from the essential scope thereof. Therefore, it is intended that the invention not be limited to the particular embodiments disclosed in the above detailed description, but that the invention will include all embodiments falling within the scope of this disclosure.

Technology Classification (CPC): 5