FIREARM ATTACHMENT ASSEMBLY FOR AMBIDEXTROUS USE

Description

BACKGROUND OF THE INVENTION

Field of the Invention

The present disclosure relates generally to accessories for firearms, more specifically, to a modular attachment block for firearm accessories, and most specifically to a folding gun stock for ambidextrous use.

Description of Related Art

Firearms, such as a rifle or a shotgun, typically include a receiver and a barrel attached to the forward end of the receiver. The receiver commonly houses the primary components of the firearm such as the firing mechanism and the firing chamber. In some modern firearms, the receiver can be further divided into an “upper receiver” and a “lower receiver,” with the lower receiver being the part that encloses the primary components of the firearm. The upper receiver in these firearms typically houses the bolt and connects to the barrel. Many firearms, particularly rifles and shotguns, include a stock or buttstock extending rearwardly from the receiver. The buttstock is the end of the firearm an operator braces himself against, typically in the shoulder area, to steady the firearm prior to and during firing events, to allow the operator to absorb recoil energy and to stabilize the firearm to ensure accuracy during firing.

While the buttstock is an important feature of the firearm, it can also add significant weight to the firearm, making certain firearms less desirable to use in certain scenarios. Further, the buttstock can significantly increase the overall length of the firearm thereby posing spatial limitations on transport and use. To reduce weight added by the buttstock, many modern rifle designs use a synthetic or composite material to form the buttstock, which is significantly lighter than hardwood.

The length that a buttstock adds to the firearm remains problematic. To address this issue, various folding and telescoping buttstocks have been made to allow for temporary reduction in the overall length of the firearm. Many telescoping buttstocks, however, reduce the overall length by only a few inches, which may not be sufficient for certain military usage and may still pose issues with handling and transport. While some folding buttstocks increase the amount of length reduction when folded, the designs are typically limited to either left-hand or right-hand folding and can be bulkier and heavier than the telescoping options. Further, the actual folding action may be cumbersome and time consuming, significantly reducing the ability of an operator to quickly fold or deploy the buttstock when needed in the field.

Firearm buttstocks also require a high level of durability to be able to withstand the rough handling firearms are typically exposed too, particularly in military and law enforcement uses. For instance, some U.S. military specifications require firearms, including an attached buttstock, to survive repeated drops from five feet high directly onto a concrete or other type of hard surface. These drop tests typically involve repeatedly dropping the firearm onto the hard surface at different angles to test the durability of specific components of the firearm, e.g., the buttstock, while ensuring overall structural integrity is maintained throughout the test. However, the structural durability of the firearm and attachments must be balanced against the continuing need to reduce the overall weight of the firearm, particularly in the context of military use where added weight to the firearm increase the total load a soldier must carry into the field.

Further improvements are needed to address all of the aforesaid problems.

SUMMARY OF THE INVENTION

The invention disclosed herein relates to an attachment platform that can mount firearm accessories to a firearm and provide for both right-hand and left-hand folding (hereafter “ambidextrous folding”) for a buttstock. In some embodiments, an ambidextrous folding gun stock assembly is disclosed. The ambidextrous folding gun stock assembly includes an attachment block, a hinge block, and a latching mechanism. The attachment block has a distal side defining a means for removably engaging a firearm receiver, and a proximal side that defines an engagement interface with a transverse engagement channel. A pair of hinge pin holes are defined at both ends of the transverse engagement channel. The hinge block removably attaches to the attachment block. The hinge block includes a stock receiving side and a latching side defining a latching interface. The latching interface includes a transverse latching channel and a pair of pin holes formed at opposite ends of the channel. The latching mechanism extends through the transverse latching channel and is partially retained therein at one end of the channel by a set pin. A removable hinge pin removably attaches the hinge block to the attachment block and extends through concentrically aligned pin holes of each component piece.

Each pair of hinge pin holes of the attachment block defines an axis of rotation for the hinge block when assembled. The axis of rotation defined by the hinge pin holes is substantially perpendicular to the direction of the transverse engagement channel. In preferred embodiments, the engagement interface is bilaterally symmetrical. Similarly, the second pair of pin holes for the hinge block defines another axis of rotation. The latching interface of the hinge block is preferably bilaterally symmetrical about this other axis of rotation.

In preferred embodiments, the transverse engagement channel of the attachment block includes a planar surface disposed between two angled surfaces defined at each end of the channel. Preferably, each angled surface is disposed between one pair of the hinge pin holes so that the pin holes are perpendicular to the channel. The body of the attachment block includes a first hook catch and a second hook catch formed in a thickness of the body. Preferably, each hook catch is formed in the body between the distal side and one of the angled surfaces formed on the proximal side. The latching mechanism is designed to engage one of the hook catches when the assembly is in a deployed position. The opposite end of the latching mechanism is designed to rotationally engage one of the angled surfaces when the assembly is in the folded position.

In some embodiments, the latching mechanism has an elongated body extending between apertures defined at either end of the body. Each of the apertures is preferably horizontally elongated or slotted, where the length of the slots defines the maximum horizontal distance the latching mechanism is movable across the hinge block. Preferably, the elongated body of the latching mechanism is greater than a horizontal length of the transverse engagement channel. A first end of the elongated body may include a hook configured to removably engage one of the hook catches and a second end, opposite the first end, may include a curved surface designed to rotatably engage one of the angled surfaces of the attachment block. Movement of the latching mechanism across the hinge block detaches the hook from the hook catch thereby allowing the hinge block to rotate about the hinge pin connecting the hinge block to the attachment block. Rotation may continue until the hinge block has been rotated substantially 180 degrees to the folded position. When folded, the curved end of the latching mechanism engages a portion of the transverse engagement channel, e.g., one of the angled surfaces, to generate a resistance force thereby securing the assembly in the folded position.

In further embodiments, the invention may relate only to a hinge block assembly. The hinge block assembly includes the hinge block and the latching mechanism attached to the hinge block. A latching side of the hinge block defines a transverse latching channel that partially encloses the latching mechanism therein. A pair of pin holes are defined at either end of the transverse latching channel. One set of the pin holes defines an axis of rotation about which the latching side is bilaterally symmetrical.

Similarly, in other embodiments the invention may relate only to the attachment block. The attachment block has a proximal side and a distal side. The distal side defines a means for removably attaching the block to a firearm receiver. The proximal side defines a mounting interface that includes a transverse engagement channel with a pair of pin holes defined at both ends thereof. The mounting interface is bilaterally symmetrical about a central axis. In some embodiments, the transverse engagement channel includes a planar surface disposed between two angled surfaces.

These and other features of the disclosed invention will become apparent to those skilled in the art in view of the following detailed disclosure.

BRIEF DESCRIPTION OF THE DRAWINGS

Other systems, methods, features and advantages of the invention will be or will become apparent to one with skill in the art upon examination of the following figures and detailed description. It is intended that all such additional systems, methods, features and advantages be included within this description, be within the scope of the invention, and be protected by the accompanying claims. Component parts shown in the drawings are not necessarily to scale, and may be exaggerated to better illustrate the important features of the invention. Dimensions shown are exemplary only. In the drawings, like reference numerals may designate like parts throughout the different views, wherein:

FIG. 1 is a perspective view of one embodiment of an ambidextrous folding gun stock assembly in a left-handed folding configuration, according to the present invention.

FIG. 2 is a perspective view of the ambidextrous folding gun stock assembly of FIG. 1 in a right-handed folding configuration.

FIG. 3 is a side view of an embodiment of the ambidextrous folding gun stock according to the present invention.

FIG. 4 is a perspective view of a distal side of one embodiment according to the invention of an attachment block isolated from the remaining components of the ambidextrous folding gun stock assembly.

FIG. 5 is a perspective view of a proximal side of the attachment block shown in FIG. 4.

FIG. 6 is a perspective view of a front end of one embodiment according to the invention of a hinge block isolated from the remaining components of the ambidextrous folding gun stock assembly.

FIG. 7 is a perspective view of a back end of the hinge block shown in FIG. 6.

FIG. 8 is a side view of one embodiment according to the invention of a latching mechanism isolated from the remaining components of the ambidextrous folding gun stock assembly.

FIG. 9 is a cross-sectional view of the latching mechanism taken along lines C-C in FIG. 8.

FIG. 10 is a cross-sectional view taken along line A-A of FIG. 3, showing the ambidextrous folding gun stock assembly in a deployed position.

FIG. 11 is a cross-sectional view of the ambidextrous folding gun stock as in FIG. 10, but shown in a folded position with the hinge block rotated clockwise 180 degrees.

FIG. 12 is a series of five images illustrating salient steps for switching an embodiment of the ambidextrous folding gun stock assembly between a left-handed folding operation and a right-handed folding operation.

FIG. 13 is a partial perspective view of the ambidextrous folding gun stock assembly showing an optics assembly in a stowed position according to one embodiment of the present invention.

FIG. 14 is a partial perspective view of the ambidextrous folding gun stock assembly of FIG. 13 showing the optics assembly in a deployed position.

FIG. 15 is a partial cross-sectional view taken along line B-B of FIG. 3 of one embodiment of the attachment block with an optics assembly deployed therefrom.

FIG. 16 is a perspective view of one embodiment according to the invention of an attachment block for attaching an external trigger assembly to a firearm.

DETAILED DESCRIPTION OF THE INVENTION

The following disclosure provides exemplary embodiments of a foldable firearm accessory attachment platform. In particular, the inventive concepts disclosed herein relate to an attachment assembly that can removably attach various firearm accessories, such as a buttstock, to a modern firearm. According to aspects of the inventive concepts disclosed herein, some embodiments of the invention may include an attachment block directly engaged to the firearm receiver. The attachment block may thereafter be used as a platform to removably attach various firearm accessories, such as a butterfly trigger assembly. In other embodiments, the invention may include an attachment block and a hinge block rotatably engaged thereto. The hinge block may rotatably attach a buttstock or other accessories to the rear of the firearm.

Throughout the following disclosure, terms such as “firearm” and “gun” may be used interchangeably and it should be understood that use of these terms is meant to refer to the broad categories of rifles and shotguns for both military and civilian use. Further, directional terms such as forward, rear, distal, proximal, etc. may be used throughout the disclosure to aid the reader in understanding the invention. These terms are made in reference to a standard firearm being handled normally so that the “forward” or “distal” end is the end having the barrel. In contrast, the “proximal” end would be the opposite end of the firearm having the buttstock. Furthermore, it should be understood that reference to a longitudinal axis is meant to refer to the imaginary axis defined by the barrel and, unless otherwise noted, reference to a “transverse” direction is meant to describe a direction with regard to the normal longitudinal axis defined by the barrel. As such, a “transverse” feature is to be understood as a feature perpendicular to the longitudinal axis of the gun. It should also be understood that left-handed and right-handed is used in reference to a standard firearm handled normally by an operator so that a “left-handed” folding action results in folding occurring down the left-side of the firearm leaving the trigger assembly exposed from the right-side.

FIG. 1 is a perspective view of one embodiment of an ambidextrous folding gun stock assembly 10 according to the present invention. The ambidextrous folding gun stock assembly 10 includes an attachment block 12 and a hinge block 14 having a latching mechanism 18 retained therein. A buttstock 16 can be removably attached to the hinge block 14. Alternatively, many other types of firearm accessories may be removably attached to the hinge block 14 or may be directly attached to the attachment block 12, depending on the requirements of the firearm and the accessory to be mounted.

Note, for ease of illustration and to ensure the focus remains on the inventive ambidextrous folding gun stock assembly 10, the firearm to which the assembly would attach is not illustrated. It should be understood that the firearm attaches to the distal side of the attachment block 12, as explained in more detail below.

The ambidextrous folding gun stock assembly 10 illustrated in FIG. 1 is configured for a left-handed folding action, which leaves the trigger assembly exposed for a right-handed shooter. In contrast, FIG. 2 is a perspective view of the ambidextrous folding gun stock assembly 10 configured for a right-handed folding action, leaving the trigger assembly exposed for a left-handed shooter. FIGS. 1 and 2 illustrate the same embodiment of the ambidextrous folding gun stock assembly 10, with the only difference being the direction in which the folding action will occur. As will be explained in further detail below, the hinge block 14 is engineered so that the latching mechanism 18 can engage either the left side or the right side of the attachment block 12, depending on need of the operator, e.g., right-handed shooter versus left-handed shooter, to allow for an ambidextrous folding action.

FIG. 3 is a side view of an embodiment of the ambidextrous folding gun stock assembly 10. The ambidextrous folding gun stock assembly 10 is illustrated as being in a deployed position for a right-handed shooter. The ambidextrous folding gun stock assembly 10 can fold down the left side of the firearm, allowing a right-handed shooter to continue operation of the firearm in either the folded or deployed positions. The same ambidextrous folding gun stock assembly 10 can be configured for a left-handed shooter so that the folding action occurs down the right side of the firearm, as discussed in more detail herein.

FIG. 4 is a perspective view of a distal side of an embodiment of the attachment block 12 according to the present invention. FIG. 5 is a perspective view of a proximal side of the attachment block 12 from FIG. 4. The attachment block 12 illustrated in FIGS. 4 and 5 has been removed from the other components of the ambidextrous folding gun stock assembly 10. The attachment block 12 has a distal side 20 (e.g., FIG. 4) distinct from its proximal side 22 (e.g., FIG. 5). A body 24 connects the distal side 20 and the proximal side 22. A means for removably attaching the attachment block 12 to a firearm receiver is formed on the distal side 20. In some embodiments, the firearm receiver attachment means may include a hook 26 and a lower locking pin channel 28. The locking pin channel 28 extends transversely through the body 24. The hook 26 may be integrally formed with and extending upwards from the distal side 20. The hook 26 is configured to engage a pocket defined in the firearm receiver. Note, the exact profile of the hook 26 may vary depending on the specific firearm to which the assembly 10 is designed to mount. When the hook 26 is properly engaged with a pocket on the firearm receiver, the locking pin channel 28 will align between opposing retention apertures on the firearm receiver and a removable retention pin may be installed through the locking pin channel 28 to secure the attachment block 12 to the firearm receiver. An example of this alignment and engagement of the attachment block 12 to a firearm receiver can be found in FIG. 16, where the attachment block 12 is utilized to attach a butterfly trigger assembly to the firearm. The retention pin may be press fit through the locking pin channel 28 to allow for easy and convenient installment or removal of the attachment block 12 to the firearm receiver. Engagement of the attachment block 12 to a firearm receiver is independent of the accessory attached to the attachment block. Thus, the interaction between the attachment block 12 and the firearm receiver illustrated in FIG. 16 is the same interaction that would be found if, for example, the hinge block 14 were attached thereto instead of to the butterfly trigger assembly.

The distal side 20 also defines a stopping surface 30. The stopping surface 30 is designed as a backstop for the internal buffer cartridge that receives the bolt as it recoils backwards under normal firing conditions. Upon discharge of the firearm, the bolt recoils backwards and contacts a spring contained within a buffer cartridge. The stopping surface 30 acts as the backstop for the buffer cartridge and prevents the buffer cartridge from being blown out of the rearward end of the firearm. The spring absorbs the recoil energy and thereafter moves the bolt forward to chamber the next round. The stopping surface 30 ensures that a firearm with the attachment block 12 mounted thereto remains operational regardless of the accessory, if any, engaged to the attachment block and regardless of whether the assembly is in the folded or deployed position.

The proximal side 22 of the attachment block 12 defines an engagement interface 32 that is bilaterally symmetrical about a central axis extending from the top end to the bottom end of the proximal side. The bilateral symmetry of the proximal side 22 adds to ambidextrous folding capability of the folding gun stock assembly 10. The engagement interface 32 includes a transverse engagement channel 34 and two pairs of hinge pin holes 36A, 36B defined at either end of the channel. Preferably, the two pairs of hinge pin holes 36A and 36B are oriented perpendicular to the direction of the transverse engagement channel 34. Each pair of hinge pin holes 36A, 36B includes an upper 35 and a lower 37 pin hole concentrically aligned with one another with the transverse engagement channel 34 extending therebetween.

In some preferred embodiments, the transverse engagement channel 34 includes a planar surface 38 disposed between two angled surfaces 40, 42. Preferably, each angled surface 40, 42 is aligned between an upper 35 and a lower 37 pin hole for each pair of pin holes 36A, 36B. In some embodiments, each angled surface 40, 42 acts as a detent surface, in cooperation with the latching mechanism 18, to secure the ambidextrous folding gun stock assembly 10 in a folded position. The attachment block 12 also includes a pair of hook catches 23 defined in the body 24 between the distal side 20 and the proximal side 22. Preferably, each hook catch 23 is defined between the distal side 20 and one of the angled surface 40, 42 of the proximal side 22. Each hook catch 23 is designed to engage a portion of the latching mechanism 18 to secure the ambidextrous folding gun stock assembly 10 in the deployed position, as shown in FIGS. 1-2.

In some embodiments of the attachment block 12, the upper surface 90 may include an optics channel 88. The optics channel 88 is engineered for the removable engagement of an optics assembly, such as assembly 86 illustrated in FIGS. 13-15 and described below. In preferred embodiments, the optics channel 88 extends through the upper surface 90 and opens into the distal side 20. A drain channel 89 may align with the optics channel 88 to allow buildup and other debris to be easily cleaned from the optics channel by an operator.

FIG. 6 is a perspective view of a front end of an embodiment of the hinge block 14 according to the present invention. FIG. 7 is a perspective view of a back end of the hinge block 14 shown in FIG. 6. The hinge block 14 illustrated in FIGS. 6 and 7 is shown isolated from the other components of the ambidextrous folding gun stock assembly 10 for ease of illustration and clarity. The hinge block 14 has a latching side 44 and a stock receiving side 46. The stock receiving side 46 includes a means for removably engaging a buttstock or other firearm accessory type. In some embodiments, the buttstock engagement means includes an internally threaded aperture 48 configured to threadably engage a buttstock such as buttstock 16. The threaded aperture 48 may extend fully through the hinge block 14 from the stock receiving side 46 to the latching side 44 to further reduce the weight of hinge block 14 and allow for easy cleaning of the block as needed.

The latching side 44 defines a latching interface 50 that will rotatably contact the engagement interface 32 of the attachment block 12 when in a deployed position. The latching interface 50 includes a transverse latching channel 52 with a pair of pin holes disposed at either end of the channel. Preferably, a pair of set pin holes 54 are defined at one end of the transverse latching channel 52 and a pair of hinge pin holes 56 are defined at the opposite end of the channel. The pair of set pin holes 54 are preferably designed to receive a press-fit set pin so as to be permanently set therein (e.g., set pin 80 shown in FIGS. 10-11). In contrast, the pair of hinge pin holes 56 are preferably designed to removably receive a hinge pin in clearance fit (e.g., hinge pin 82 shown in FIGS. 10-11). The transverse latching channel 52 is sized to house the latching mechanism 18, as described in more detail below.

The transverse latching channel 52 is formed between a first rail 58 and a second rail 60. Each pin hole in the pair of set pin holes 54 and each pin hole in the pair of hinge pin holes 56 is defined through one of the first rail 58 and the second rail 60. The pin holes 54, 56 are perpendicular to the direction of the transverse latching channel 52. Further, each hole in each pair of pin holes 54 and 56 is concentrically aligned with the opposing hole from that pair of holes 54 or 56, with the transverse latching channel 52 extending therebetween. Preferably, the first rail 58 and the second rail 60 include a rotational stopping surface 62 formed proximate to the set pin holes 54. The rotational stopping surfaces 62 are thickened portions of the first and second rails 58, 60 formed to rotatably contact a portion of the planar surface 38 to limit the maximum rotation of the hinge block 14 in the direction the attachment block 12 when the ambidextrous folding gun stock assembly 10 is in a deployed position. The rotational stopping surfaces 62 also differentiate the set pin holes 54 from the hinge pin holes 56 because the rotational stopping surfaces 62 are only formed on the set pin side of the transverse latching channel 52. It is preferred that the hinge pin holes 56 be configured to receive the hinge pin 82 in a clearance fit engagement so that the hinge block 14 may be quickly detached from the attachment block 12 to switch the configuration from left-handed to right-handed (or vice versa). In contrast, the set pin holes 54 receive the set pin 80 in a press fit engagement to ensure the latching mechanism 18 is at least partially retained in the transverse latching channel 52 regardless of whether the hinge block 14 is attached to the attachment block 12. In this manner, the latching mechanism 18 is also at all times at least partially engaged to the hinge block 14.

The pair of hinge pin holes 56 define an axis of rotation about which the hinge block 14 can rotate when installed to the attachment block 12 to form the ambidextrous folding gun stock assembly 10. In preferred embodiments, the hinge block 14 can rotate around the axis defined by the hinge pin holes 56 substantially 180 degrees off the engagement interface 32 of the attachment block 12. The latching interface 50 is also designed to be bilaterally symmetrical about the rotational axis of the hinge pin holes 56. That is, the hinge block can be flipped or inverted substantially 180 degrees about the axis of the hinge pin holes 56 resulting in a mirror image of the latching interface 50. The bilateral symmetry of the latching interface 50 defined by the axis of the hinge pin holes 56 aids in making the folding gun stock assembly 10 ambidextrous for both left-handed and right-handed folding actions, as explained in more detail below.

FIG. 8 is a side view of an embodiment of a latching mechanism 18, isolated from the hinge block 14, according to aspects of the present invention. FIG. 9 is a cross-sectional view of the latching mechanism, taken along lines C-C of FIG. 8. The latching mechanism 18 includes a hook 64 formed at one end and a curved cam 66 formed at an end opposite the hook. The hook 64 and the curved cam 66 are integrally connected by an elongated body 68. The curved cam 66 is oriented in the opposite direction of the hook 64. The elongated body 68 is preferably longer than a horizontal length of the transverse latching channel 52 so that the latching mechanism 18 can move therethrough for purposes of engaging and disengaging the attachment block 12.

A first aperture 70 is defined through the elongated body 68 proximate to the hook 64. Similarly, a second aperture 72 is defined through the elongated body 68 at the opposite end proximate to the curved cam 66. Each of the first aperture 70 and the second aperture 72 are slotted or horizontally elongated. As such, these features will be referred to as the first slot 70 and the second slot 72 hereafter. The length of each of the first slot 70 and the second slot 72 defines the maximum horizontal distance the latching mechanism 18 is movable across the transverse latching channel 52. The horizontal movement of the latching mechanism 18 is designed to lock and unlock the ambidextrous folding gun stock assembly 10 in a deployed position and rotatably secure and unsecure the hinge block 14 in a folded position.

An internal channel 74 is defined within the elongated body 68 and extends from the first slot 70 towards the second slot 72. A drain channel 76 connects one end of the internal channel 74 to the second slot 72 and provides a convenient escape path for any buildup that may need to be cleaned out from the latching mechanism 18. A compression spring 78, e.g., see FIGS. 10-11, is housed in the internal channel 74. When the latching mechanism 18 is installed in the hinge block 14, the spring 78 is fixed at one end of the internal channel 74 in the first slot 70 and extends towards the second slot 72. The spring 78 terminates at the drain channel 76, which has a diameter less than the diameter of the internal channel 74. The spring 78 provides a compressive force to secure the hook 64 in engagement with a hook catch 23 when the hinge block 14 is in the deployed position and to engage the curved cam 66 against the angled surface 40 or 42 when the hinge block 14 is in the folded position. The spring 78 is retained in internal channel 74 by set pin 80 extending through the first slot 70 when the latching mechanism 18 is installed in the hinge block 14.

FIG. 10 is a top-down cross sectional view of an embodiment of the ambidextrous folding gun stock assembly 10 in a deployed position. FIG. 10 is taken along section line A-A marked in FIG. 3. A set pin 80 extends through the pair of set pin holes 54 and the first slot 70 to fixedly attach the latching mechanism 18 to the hinge block 14 at one end of the transverse latching channel 52. The set pin 80 also secures the spring 78 within the internal channel 74 and is fixed partially in the first slot 70. At the opposite end, a removable hinge pin 82 extends through one of the pairs of the pin holes 36A or 36B, through the hinge pin holes 56 and through the second slot 72 to rotatably attach the hinge block 14 to the attachment block 12. The hook 64 removably engages the hook catch 23 defined in the body 24 of the attachment block 12 to lock the ambidextrous folding gun stock assembly 10 in the deployed position, as shown in FIG. 10.

To effectuate the folding action, an operator first applies a force to the latching mechanism 18 at the curved cam 66 in the direction of arrow Y shown in FIG. 10. The force applied to the latching mechanism 18 in direction Y compresses the spring 78 allowing the latching mechanism 18 to move in the same direction in which the force is applied. The set pin 80 and the hinge pin 82 will engage an inner edge of the first slot 70 and second slot 72, respectively, to limit the distance the latching mechanism 18 can move horizontally. When the force Y is applied to the latching mechanism 18, the hook 64 disengages the hook catch 23 allowing the hinge block 14 to rotate about the axis defined by the hinge pin 82. Once the hook 64 has disengaged from the hook catch 23, the force Y may be removed from the latching mechanism 18 allowing it to return to its original position on the hinge block 14.

To complete folding of the gun stock assembly 10, a rotational force is applied to the hinge block 14 in the direction of arrow X shown in FIG. 10, causing the hinge block 14 to rotate about the hinge pin 82 and away from the attachment block 12. As the hinge block 14 continues to rotate about the hinge pin 82, the curved cam 66 comes into contact with the one of the angled surfaces 40, 42 which applies a counter force to the latching mechanism 18 again compressing the spring 78. The hinge block 14 continues to rotate in direction X until the curved cam 66 overcomes the angled surface 40 or 42 and the compressive force applied to the spring 78 is relieved. The latching mechanism 18 moves back to its original positioning in the hinge block 14 and the curved cam 66 is maintained in frictional engagement with the angled surface 40 or 42. The frictional engagement between the curved cam 66 and the angled surface 40 or 42 secures the assembly 10 in the folded position.

FIG. 11 is a top-down cross sectional view of an embodiment of the ambidextrous folding gun stock assembly 10 in a folded position. FIG. 11 is the same cross-sectional view as FIG. 10, but shows the assembly in a folded position with the hinge block rotated clockwise 180 degrees. The curved cam 66 engages the angled surfaces 40 or 42 to secure the gun stock assembly 10 in the folded position. The hinge block 14 is attached to one side of the attachment block 12 through either pin holes 36A or pin holes 36B so that the hinge block 14 can rotate about the hinge pin 82 between the deployed position (e.g., FIG. 10) and the folded position (e.g., FIG. 11). To ensure the rotational capability is achieved, the second slot 72 is concentrically aligned with the hinge pin holes 56 in the hinge block 14 and the same hinge pin holes 56 are thereafter concentrically aligned with one of the pairs of pin holes 36A or 36B prior to installation of the removable hinge pin 82. The removable hinge pin 82 defines the axis of rotation and securely attaches the hinge block 14 to the attachment block 12.

To re-deploy the folding gun stock assembly 10, an operator applies a rotational force to the hinge block 14 in the direction of arrow Z. The hinge block 14 begins to rotate about the hinge pin 82 and the curved cam 66 engages the angled surface 40 or 42 to begin compressing the spring 78 and move the latching mechanism 18 across the transverse latching channel 52. An operator continues application of the rotational force Z until the curved cam 66 overcomes the angled surface 40 or 42 relieving the compression of the spring 78. Rotation of the hinge block 14 continues until it is substantially in line with the longitudinal axis of the firearm. At this point, an operator again applies a compressive force Y (e.g., FIG. 10) to the curved cam 66 end of the latching mechanism 18 to move the latching mechanism across the transverse latching channel 52 so that the hook 64 can re-engage one of the hook catches 23. The force is then removed causing the latching mechanism 18 to return to its original position with the hook 64 securely engaged with a hook catch 23.

In FIGS. 10 and 11, the ambidextrous folding gun stock assembly 10 is configured for a right-handed operator. That is, the ambidextrous folding gun stock assembly 10 as depicted folds along the left side of the firearm so that the right-handed operator can access the trigger from the right side thereby ensuring the firearm remains operational in both the folded and the deployed positions. The folding and deploying actions can be accomplished with one hand, e.g., the left hand in the depicted configuration, with the other hand free to continue holding and firing the firearm.

In some preferred embodiments, the spring 78 has a spring rate of at least 8 pounds of force (“lbf”), which is sufficient to secure the latching mechanism 18 in both the folded and deployed positions. Along similar lines, the angle for each angled surface 40, 42 is preferably about 20 degrees, defined from the planar surface 38 and extending toward the distal side 20. A spring 78 having a spring rate of at least 8 pounds of force and a 20 degree angle for each angled surface 40, 42 has been determined to provide adequate retention torque to lock the hinge block 14 in the folded position while requiring a minimal amount of force to overcome the retention torque for rapid deployment from the folded position. Further, an 8 lbf spring rate for the spring 78 has been determined to be optimal to ensure the ambidextrous folding gun stock assembly 10 is secured in the deployed position while requiring a minimal amount of force to activate the latching mechanism 18 to begin the folding action.

FIG. 12 is a series of perspective views of an embodiment of the ambidextrous folding gun stock 10 illustrating the salient steps for switching from a right-handed configuration to a left-handed configuration, according to the present invention. As used herein, it should be understood that a right-handed configuration is meant to refer to the folding gun stock assembly 10 being configured for a right-handed operator so that the hinge block 14 is folded down the left side of the firearm to leave the trigger assembly accessible from the right side. Similarly, the left-handed configuration is meant to refer to the folding gun stock assembly 10 being configured for a left-handed operator so that the hinge block 14 is folded down the right side of the firearm to leave the trigger assembly accessible from the left side.

The firearm has been omitted from this series of images in FIG. 12 for purposes of clarity and to ensure the focus remains on the inventive assembly 10. Similarly, through several of the illustrated steps, the buttstock 16 has been purposefully omitted for clarity purposes.

Starting at the top left side of the page, Step 1 illustrates a portion of the ambidextrous folding gun stock assembly 10 as deployed in a right-handed configuration. To swap the folding gun stock assembly 10 into a left-handed configuration, the operator at Step 2 removes the hinge pin 82 from the assembly 10 to detach the hinge block 14 from the attachment block 12. For descriptive purposes only, the left pair of pin holes on the attachment block 12 may be identified as pin holes 36A and the right pair of pin holes on the attachment block 12 may be identified as pin holes 36B. As illustrated for this example, the hinge pin 82 is removed from the pair of pin holes 36A on the left side of the attachment block 12. When the assembly 10 is installed on a firearm, the attachment block 12 remains attached thereto throughout the ambidextrous flipping operation. A small punch or other type of durable cylindrical tool may be used to remove the hinge pin 82 from the assembly 10. The latching mechanism 18 is retained in the hinge block 14 by the set pin 80, which is not removed during the process.

At Step 3, the hinge block 14 is flipped or inverted 180 degrees around the axis defined by the pair of hinge pin holes 56 so that the hook 64 is oriented in a direction opposite from its original direction (e.g., right versus left). Once the hinge block 14 is inverted, at Step 4 the hinge block is realigned in the transverse engagement channel 34 so that the pair of hinge pin holes 56 and the second slot 72 are aligned between the pair of pin holes 36B on the right side of the attachment block 12. The hook 64 may also be positioned to engage a hook catch 23 during the realignment of the hinge block 14 with the attachment block 12. The hinge pin 82 is reinstalled through the concentrically aligned pin holes 36B, 56 and 72 to rotatably secure the hinge block 14 to the right side of the attachment block 12.

The bilateral symmetry of the engagement interface 32 ensures that the hinge block 14 can be readily attached to the attachment block 12 regardless of whether it is in a right-handed or left-handed configuration. Further, by designing the latching interface 50 to be bilaterally symmetrical about the rotational axis defined by the hinge pin holes 56, an operator can quickly switch between the right-handed and left-handed configurations by removing the hinge pin 82 and inverting the hinge block 14 prior to reinstalling the hinge pin on the opposite side. Operation of the ambidextrous folding gun stock assembly 10 is the same regardless of whether it is installed in a right-handed or left-handed configuration, with the only difference being the direction in which the folding action takes place.

Once the hinge block 14 has been inverted and reinstalled on the opposite side of the attachment block 12, Step 5 requires flipping the orientation of the buttstock 16. To effectuate this flip of the buttstock 16, an operator can loosen a removable locking ring 84 installed with the buttstock 16 so that the buttstock can be rotated substantially 180 degrees about the longitudinal firearm axis. The operator simply tightens the locking ring 84 once the buttstock 16 is properly oriented thereby locking the buttstock in position.

FIG. 13 is a perspective view of a portion of an ambidextrous folding gun stock assembly 10 according to one embodiment of the present invention. The ambidextrous folding gun stock assembly 10 may include an adjustable sight optic assembly 86. FIG. 13 illustrates the optic assembly 86 in stowed position. FIG. 14 is a perspective view of a portion of the ambidextrous folding gun stock assembly 10 with the optic assembly 86 in a deployed position. The optic assembly 86 includes a sight post 94 having a plurality of notches 96 defined along the vertical length of the post 94. A windage adjustment assembly 98 is formed at the top end of the sight post 94 and includes an adjustment knob 100 configured to incrementally move a sight 102 horizontally across the assembly 98.

Preferably, the optic assembly 86 is removably installed in the optics channel 88 defined through the upper surface 90 of the body 24 of the attachment block 12. A sight lock 92 is retained in the body 24 proximate the upper surface 90 and extends partially through the optic channel 88 to engage a portion of the sight optic 86 to provide incremental adjustment thereof. FIG. 15 is a magnified cross-sectional view of a portion of the attachment block 12 having an optic assembly 86 installed therein. FIG. 15 is taken along section lines B-B marked in FIG. 3. The sight post 94 extends through the optics channel 88 defined through the top surface 90 of the attachment block 12. The sight lock 92 includes a spring loaded locking tab 104 which extends partially into the optics channel 88 to engage one of the plurality of notches 96 defined along the vertical length of the sight post 94. To adjust the sight optic 86, an operator would depress the sight lock 92 so the spring loaded locking tab 104 disengages from the sight post 94 allowing vertical adjustment thereof. Once the operator has set the sight post 94 to the desired height, the sight lock 92 is released so the spring loaded locking tab 104 can re-engage one of the notches 96 along the sight post 94 to lock the post at the set height.

Each of the plurality of incremental notches 96 allows for the incremental vertical adjustment of the optic assembly 86 corresponding to a downrange distance. Preferably, the plurality of notches 96 correspond to a downrange distance between 0 meters to 20 meters thereby allowing the operator to quickly adjust the sight optic 86 for accurate shooting between 0 and 20 meters using only the included metal sights. The windage adjustment assembly 98 is preferably adjustable between (+) 6 and (−) 6 millimeters to provide for a variety of incremental adjustments accounting for present windage.

FIG. 16 is a partial perspective view of one embodiment of an attachment block 12 used to mount a firearm accessory other than a foldable buttstock, such as a butterfly trigger assembly 112. To mount an alternative firearm accessory which does not require a folding action, an operator will only need the attachment block 12. The attachment block 12 engages the firearm receiver, as described above, by engaging the hook 26 in a pocket 114 defined in the firearm receiver 1. Similarly, the lower locking pin channel 28 is aligned between pin apertures 115 formed on the receiver 1 and a pin 116 is installed therethrough to secure the attachment block 12 to the firearm receiver 1.

Once the attachment block 12 is installed to the firearm receiver 1, two set pins 110 can be used to secure an external firearm accessory to the engagement interface 32. As shown, a butterfly trigger assembly 112 is mounted to the attachment block 12 using the two set pins 110. Each set pin 110 will extend through one pair of the pin holes 36A, 36B and through a portion of the accessory, e.g., butterfly trigger assembly 112, to secure the accessory to the engagement interface 32.

While the invention has been described with regard to an ambidextrous folding gun stock assembly, the attachment block can also serve as a mounting interface for removably mounting a firearm to a vehicle or other type of firing station. In such embodiments, the mounting interface on the vehicle or firing station may provide the mechanical linkage to activate the trigger assembly while the attachment block provides an easy and convenient interface to quickly mount and dismount the firearm, as needed. Such a configuration will allow an operator to quickly retrieve a mounted firearm to allow continued use of that firearm away from its initial mounted position, for instance in the case where the vehicle has become disabled.

Exemplary embodiments of the invention have been disclosed in an illustrative style. Accordingly, the terminology employed throughout should be read in a non-limiting manner. Although minor modifications to the teachings herein will occur to those well versed in the art, it shall be understood that what is intended to be circumscribed within the scope of the patent warranted hereon are all such embodiments that reasonably fall within the scope of the advancement to the art hereby contributed, and that that scope shall not be restricted, except in light of the appended claims and their equivalents.