Bi-folding Buttstock Hinge System, Device and Assembly

Abstract

Embodiments of a bi-folding buttstock hinge system, device and assembly include multiple spring-loaded hinge pins that operate in an opposed manner. Each pair of opposed pins is maintained in a hinge plate and can drive across a shear line to latch and detach from a receiver back plate. In various embodiments, a leaf spring acting on the hinge plate can bias the movement and retention of the hinge plate's position while minimizing rattling of parts. Among different advantages, the presently disclosed embodiments facilitate a firearm stock folding to the left and right while being completely removable from the firearm.

1 . A buttstock hinge assembly, comprising:
 a hinge plate comprising a back wall formed with first and second arms, wherein each of the first and second arms comprises a substantially cylindrical wall having an opening extending therethrough;   a first hinge spring positioned in the opening of the first arm, wherein the first hinge spring has a first axial end and a second axial end;   a second hinge spring positioned in the opening of the second arm, wherein the second hinge spring has a primary axial end and a secondary axial end;   a first hinge pin operably engaged with the first axial end of the first hinge spring;   a second hinge pin operably engaged with the second axial end of the first hinge spring;   a primary hinge pin operably engaged with the primary axial end of the second hinge spring;   a secondary hinge pin operably engaged with the secondary axial end of the second hinge spring;   a receiver back plate securable to the hinge plate, wherein the receiver back plate comprises upper left, upper right, lower left and lower right collar arms, wherein each of the collar arms has a bore opening extending therethrough;   a first activation button retained at least partially within the upper left collar arm bore opening, wherein the first activation button is operably engageable with the first hinge pin;   a second activation button retained at least partially within the lower left collar arm bore opening, wherein the second activation button is operably engageable with the second hinge pin;   a third activation button retained at least partially within the upper right collar arm bore opening, wherein the third activation button is operably engageable with the primary hinge pin;   a fourth activation button retained at least partially within the lower right collar arm bore opening, wherein the fourth activation button is operably engageable with the secondary hinge pin;   wherein the first and second hinge pins are disengageable from the upper left and lower left collar arms upon pressure being applied to the first and second activation buttons, respectively; and   wherein the primary and secondary hinge pins are disengageable from the upper right and lower right collar arms upon pressure being applied to the third and fourth activation buttons, respectively.   
     
     
         2 . The buttstock hinge assembly of  claim 1 , further comprising a leaf spring secured to a center wall of the receiver back plate, wherein the leaf spring is operably engageable with the hinge plate. 
     
     
         3 . The buttstock hinge assembly of  claim 1 , wherein the first and second hinge pins are at least partially positioned within the opening of the first arm, and wherein the primary and secondary hinge pins are at least partially positioned within the opening of the second arm. 
     
     
         4 . The buttstock hinge assembly of  claim 1 , wherein the bore openings of the upper left and lower left collar arms are axially aligned, and wherein the bore openings of the upper rights and lower right collar arms are axially aligned. 
     
     
         5 . The buttstock hinge assembly of  claim 1 , wherein the first, second, primary and secondary hinge pins are formed with an outer wall comprising a taper from a first diameter to a second diameter, wherein the first diameter is larger than the second diameter. 
     
     
         6 . The buttstock hinge assembly of  claim 5 , wherein each of the bore openings comprises a bore diameter that is larger than the second diameter and smaller than the first diameter of each of the first, second, primary and secondary hinge pins. 
     
     
         7 . The buttstock hinge assembly of  claim 1 , wherein the receiver back plate comprises a center wall formed with a slot extending therethrough, wherein the hinge assembly further comprises a center wall spring and first and second detents maintained within the slot, wherein the first detent is engageable with the first activation button and wherein the second detent is engageable with the second activation button. 
     
     
         8 . The buttstock hinge assembly of  claim 7 , wherein each of the first and third activation buttons comprises a button outer wall formed with an indentation therein, wherein the first detent is engageable with the outer wall indentation of the first activation button and wherein the second detent is engageable with the outer wall indentation of the second activation button. 
     
     
         9 . The buttstock hinge assembly of  claim 1 , wherein the receiver back plate is formed with a ramp wall proximate each of the upper left, upper right, lower left and lower right collar arms. 
     
     
         10 . The buttstock hinge assembly of  claim 1 , wherein the receiver back plate is secured to a firearm. 
     
     
         11 . A buttstock hinge assembly, comprising:
 a receiver back plate comprising a left collar assembly and a right collar assembly;   a hinge plate;   a first hinge assembly removably securing the hinge plate to the left collar assembly; and   a second hinge assembly removably securing the hinge plate to the right collar assembly.   
     
     
         12 . The buttstock hinge assembly of  claim 11 , wherein the left collar assembly comprises upper left and lower left collar arms, wherein each of the upper left and lower left collar arms comprises a bore opening extending therethrough, wherein the left collar assembly further comprises a first activation button retained at least partially within the upper left collar arm bore opening and a second activation button retained at least partially within the lower left collar arm bore opening; and
 wherein the right collar assembly comprises upper right and lower right collar arms, wherein each of the upper right and lower right collar arms comprises a bore opening extending therethrough, wherein the right collar assembly further comprises a third activation button retained at least partially within the upper right collar arm bore opening and a fourth activation button retained at least partially within the lower right collar arm bore opening.   
     
     
         13 . The buttstock hinge assembly of  claim 12 , wherein the left collar assembly further comprises a first activation button retained at least partially within the upper left collar arm bore opening and a second activation button retained at least partially within the lower left collar arm bore opening, and wherein the right collar assembly further comprises a third activation button retained at least partially within the upper right collar arm bore opening and a fourth activation button retained at least partially within the lower right collar arm bore opening. 
     
     
         14 . The buttstock hinge assembly of  claim 11 , wherein the hinge plate comprises a back wall formed with first and second arms, wherein each of the first and second arms comprises a substantially cylindrical wall having an opening extending therethrough;
 wherein the first hinge assembly comprises a first hinge spring positioned in the opening of the first arm and comprising a first axial end and a second axial end,   wherein the first hinge assembly further comprises a first hinge pin operably engaged with the first axial end of the first hinge spring and a second hinge pin operably engaged with the second axial end of the first hinge spring;   wherein the second hinge assembly comprises a second hinge spring positioned in the opening of the second arm and comprising a primary axial end and a secondary axial end; and   wherein the second hinge assembly further comprises a primary hinge pin operably engaged with the primary axial end of the second hinge spring and a secondary hinge pin operably engaged with the secondary axial end of the second hinge spring.   
     
     
         15 . The buttstock hinge assembly of  claim 11 , further comprising a leaf spring secured to a center wall of the receiver back plate, wherein the leaf spring is operably engageable with the hinge plate. 
     
     
         16 . The buttstock hinge assembly of  claim 12 , wherein the bore openings of the upper left and lower left collar arms are axially aligned, and wherein the bore openings of the upper rights and lower right collar arms are axially aligned. 
     
     
         17 . The buttstock hinge assembly of  claim 14 , wherein the first, second, primary and secondary hinge pins are formed with an outer wall comprising a taper from a first diameter to a second diameter, wherein the first diameter is larger than the second diameter. 
     
     
         18 . The buttstock hinge assembly of  claim 17 , wherein each of the bore openings comprises a bore diameter that is larger than the second diameter and smaller than the first diameter of each of the first, second, primary and secondary hinge pins. 
     
     
         19 . The buttstock hinge assembly of  claim 12 , wherein the receiver back plate is formed with a ramp wall proximate each of the upper left, upper right, lower left and lower right collar arms. 
     
     
         20 . The buttstock hinge assembly of  claim 11 , wherein the receiver back plate is secured to a firearm.