Firearm accessory clamp mount having rotatable locking lever and lower adjustment nut

Abstract

An adjustable accessory mounting mechanism for firearms has an accessory mount rail having clamp surfaces. A mount base member has a clamp structure in retaining engagement with the clamp surfaces and supports a clamp plate member for rotary clamping engagement with the accessory mount rail. A clamp retainer screw extends through the retainer opening and pivotally supports the clamp plate member for rotary locking and unlocking movement. An adjustment nut member is threaded to the clamp retainer screw and adjusts the position of the clamp plate member. The adjustment nut is located below the lower surface of the clamp plate and clamp support to prevent its catching on brush, vines and other objects during field use.

I claim: 
     
         1 . An adjustable accessory mounting mechanism, comprising:
 an accessory mount rail having clamp surfaces;   a mount base member having a clamp structure disposed for retaining engagement with said clamp surfaces;   a clamp support structure being defined by said mount base member having upper and lower surfaces and defining a retainer opening;   a clamp member having a clamping portion disposed for clamping engagement with a clamp surface of said accessory mount rail and being moveable to a locking position securing said mount base member to said mount rail and to an unlocked position permitting removal of said mount base from said mount rail;   a clamp retainer member extending through said retainer opening and pivotally supporting said clamp member for locking and unlocking movement; and   an adjustment member having adjusting engagement with said clamp retainer member and having positioning engagement with said clamp member, said adjustment member being located below said lower surface of said clamp support structure.   
     
     
         2 . The adjustable accessory mounting mechanism of  claim 1 , comprising:
 said clamp member having rotary movement relative to said clamp support structure and having upper and lower clamp surfaces and defining an elongate tapered cam surface establishing camming relationship with a clamp surface of said accessory mount rail;   said clamp retainer member being a retainer screw having a lower threaded end; and   said adjustment member being a retainer nut being threaded to said lower threaded end of said clamp retainer member and having position controlling engagement with said lower clamp surface of said clamp member.   
     
     
         3 . The adjustable accessory mounting mechanism of  claim 1 , comprising:
 said clamp retainer member being a retainer screw having a shaft portion of non-circular configuration; and   said clamp member having a retainer screw aperture of non-circular internal configuration and establishing a non-rotatable and linearly moveable relation with said non-circular shaft portion of said clamp retainer member.   
     
     
         4 . The adjustable accessory mounting mechanism of  claim 1 , comprising:
 an actuating lever extending from said clamp member and being manually rotatable for imparting rotary locking and unlocking movement to said clamp member.   
     
     
         5 . The adjustable accessory mounting mechanism of  claim 4 , comprising:
 a lock member being mounted to said mount base member and having an actuating lever locking position engaging said actuating lever when said clamp member is located at said locked position thereof and preventing unlocking rotation of said actuating lever, said lock member having an actuating lever release position permitting manual rotation of said actuating lever and said clamp member from said locking position.   
     
     
         6 . The adjustable accessory mounting mechanism of  claim 1 , comprising:
 said clamp support structure being a clamp support platform having upper and lower platform surfaces;   an annular bushing insert being located within said retainer opening and having a lower end projecting downwardly beyond said lower platform surface; and   said clamp member engaging said lower end of said annular bushing insert and having spaced relation with said lower platform surface.   
     
     
         7 . The adjustable accessory mounting mechanism of  claim 1 , comprising:
 a spring member being located within said retainer opening and having force transmitting engagement with said clamp retainer member and said clamp member and maintaining said clamp member in engagement with said adjustment member.   
     
     
         8 . The adjustable accessory mounting mechanism of  claim 1 , comprising:
 an upwardly facing annular support shoulder being defined within said retainer opening of said clamp support structure; and   an annular bushing insert being located within said retainer opening and having positioning engagement with said upwardly facing annular support shoulder.   
     
     
         9 . The adjustable accessory mounting mechanism of  claim 1 , comprising:
 an annular bushing insert being located within said retainer opening and having a circular recess therein;   said clamp retainer member being a retainer screw having a head portion located within said circular recess of said annular bushing insert and defining a downwardly facing annular spring retainer groove;   an annular spring member having an upper end portion seated within said downwardly facing annular spring retainer groove and having a lower end portion disposed in force transmitting relation with said clamp member.   
     
     
         10 . The adjustable accessory mounting mechanism of  claim 1 , comprising:
 an insert member being located within said retainer opening and defining a circular rim and a retainer receptacle;   said clamp retainer member being a retainer screw having a screw head portion located within said retainer receptacle; and   said screw head portion and said circular rim of said insert member being substantially positioned in alignment and being in substantial alignment with said upper surface of said mount base member, thus providing said mount base with a substantially unobstructed upper surface and minimizing the potential for inadvertently catching the mount base on brush and other field debris during handling in the field.   
     
     
         11 . An adjustable accessory mounting mechanism, comprising:
 an accessory mount rail having angulated clamp surfaces;   a mount base member having internal angulated clamp surface structure disposed for retaining engagement with said clamp surfaces of said accessory mount rail;   a clamp support structure being defined by said mount base member having upper and lower surfaces and defining a retainer opening;   a rotary clamp plate member having a tapered cam surface clamping portion disposed for camming engagement with a tapered clamp surface of said accessory mount rail and being rotatably moveable to a locking position securing said mount base member to said mount rail and to an unlocked position permitting removal of said mount base from said mount rail;   a clamp retainer screw member extending through said retainer opening and supporting said rotary clamp plate member for rotary locking and unlocking movement; and   an adjustment nut member being threaded to said clamp retainer member and having positioning engagement with said clamp plate member, said adjustment nut member and a lower end portion of said clamp retainer screw being located below said lower surface of said clamp support structure.   
     
     
         12 . The adjustable accessory mounting mechanism of  claim 11 , comprising:
 said rotary clamp plate member having rotary movement relative to said clamp support structure and having upper and lower clamp surfaces and defining an elongate tapered cam surface at its periphery establishing camming relationship with a tapered clamp surface of said accessory mount rail;   said clamp retainer member being a retainer screw having a lower threaded end and having a shaft portion of non-circular configuration;   said clamp member having a retainer screw aperture of non-circular internal configuration and establishing a non-rotatable and linearly moveable relation with said non-circular shaft portion of said clamp retainer member; and   said adjustment member being a retainer nut being threaded to said lower threaded end of said clamp retainer member and having position controlling engagement with said lower clamp surface of said clamp screw.   
     
     
         13 . The adjustable accessory mounting mechanism of  claim 11 , comprising:
 an actuating lever extending from said clamp member and being manually rotatable for imparting rotary locking and unlocking movement to said clamp member.   
     
     
         14 . The adjustable accessory mounting mechanism of  claim 13 , comprising:
 a lock member being mounted to said mount base member and having an actuating lever locking position engaging said actuating lever when said clamp member is located at said locked position thereof and preventing unlocking rotation of said actuating lever, said lock member having an actuating lever release position permitting manual rotation of said actuating lever and said clamp member from said locking position.   
     
     
         15 . The adjustable accessory mounting mechanism of  claim 11 , comprising:
 said clamp support structure being a clamp support platform having upper and lower platform surfaces;   an annular bushing insert being located within said retainer opening and having a lower end projecting downwardly beyond said lower platform surface, said annular bushing insert defining a circular insert rim and defining a retainer receptacle;   said clamp plate member engaging said lower end of said annular bushing insert and having spaced relation with said lower platform surface; and   a spring member being located within said retainer opening and having force transmitting engagement with said clamp retainer member and said clamp plate member and maintaining said clamp plate member in engagement with said adjustment nut member.   
     
     
         16 . The adjustable accessory mounting mechanism of  claim 11 , comprising:
 a spring member being located within said retainer opening and having force transmitting engagement with said clamp retainer member and said clamp member and maintaining said clamp member in engagement with said adjustment member.   
     
     
         17 . The adjustable accessory mounting mechanism of  claim 11 , comprising:
 an upwardly facing annular support shoulder being defined within said retainer opening of said clamp support structure; and   an annular bushing insert being located within said retainer opening and being seated on said upwardly facing annular support shoulder.   
     
     
         18 . The adjustable accessory mounting mechanism of  claim 11 , comprising:
 an annular bushing insert being located within said retainer opening and having a circular recess therein;   said clamp retainer member being a retainer screw having a head portion located within said circular recess of said annular bushing insert and defining a downwardly facing annular spring retainer groove;   an annular spring member having an upper end portion seated within said downwardly facing annular spring retainer groove and having a lower end portion disposed in force transmitting relation with said clamp member.   
     
     
         19 . The adjustable accessory mounting mechanism of  claim 11 , comprising:
 an insert member being located within said retainer opening and having a circular rim defining a retainer receptacle;   said clamp retainer member being a retainer screw having a screw head portion located within said retainer receptacle; and   said screw head portion and said circular rim of said insert member being substantially positioned in alignment and being in substantial alignment with said upper surface of said mount base member, thus providing said mount base with a substantially unobstructed upper surface and minimizing the potential for inadvertently catching the mount base on brush and other field debris during handling in the field.