Patent Publication Number: US-2021180916-A1

Title: Weapon anti-cant indicator

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
     The present application claims priority to U.S. Provisional Patent App. No. 62/948,618, filed Dec. 16, 2019, which is hereby incorporated by reference in its entirety. 
    
    
     FIELD 
     The present disclosure generally relates to firearm accessories, and more particularly to a weapon anti-cant indicator. 
     BACKGROUND 
     Various types of weapons (e.g., firearms) include sights for aiming the weapons toward a target downrange. In general, it is desirable to avoid canting a weapon such as a rifle so that a sight of the rifle is directly above a bore of the rifle. 
     SUMMARY 
     In one aspect, an anti-cant indicator assembly is for indicating the orientation of a weapon with respect to vertical. The anti-cant indicator assembly includes a mount configured to mount to the weapon, a level including a vial containing a bubble, and a pivot connection connecting the level to the mount. The pivot connection is configured to permit movement of the level with respect to the mount about the pivot connection between an operational position in which the bubble can be referenced by the user for indicating orientation of the weapon with respect to vertical, and a stowed position different from the operational position. The pivot connection includes a retainer configured to releasably retain the level in at least one of the operational position or the stowed position. 
     In another aspect, an anti-cant indicator assembly is for indicating the orientation of a weapon with respect to vertical. The anti-cant indicator assembly includes a mount configured to mount to the weapon. The anti-cant indicator includes a bracket and a vial containing a bubble. The bracket is connected to the mount. A pivot connection connects the vial to the bracket. The pivot connection is configured to permit movement of the vial with respect to the bracket and the mount about the pivot connection between an operational position in which the bubble can be referenced by a user for indicating orientation of the weapon with respect to vertical, and a stowed position different from the operational position. The bracket is selectively movable with respect to the mount to change an orientation of the vial with respect to the mount in the operational position. 
     In another aspect, the anti-cant indicator assembly is for indicating the orientation of a weapon with respect to vertical. The weapon includes a forward end which a user points toward a target for aiming the weapon at the target. The anti-cant indicator assembly includes a mount configured to mount to the weapon. The mount includes a forward portion and a rearward portion. The forward portion is arranged to be in front of the rearward portion when the mount is mounted on the firearm. The anti-cant indicator includes a level including a vial containing a bubble, and a pivot connection connecting the vial to the mount. The pivot connection is configured to permit movement of the vial with respect to the mount and the weapon about the pivot connection between an operational position in which the bubble can be referenced by a user for indicating orientation of the weapon with respect to vertical, and a stowed position different from the operational position. The pivot axis of the pivot connection extends in a rearward-to-forward orientation with respect to the mount. 
     Other objects and features of the present disclosure will be in part apparent and in part pointed out herein. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a perspective of a first embodiment of a weapon aiming accessory of the present disclosure; 
         FIG. 2  is a perspective of a mount and anti-cant indicator of the weapon aiming accessory of  FIG. 1 ; 
         FIG. 3  is a rear elevation of the mount of  FIG. 2 , the anti-cant indicator being shown in a stowed position; 
         FIG. 4  is a rear elevation similar to  FIG. 3  but showing the anti-cant indicator in an operational position; 
         FIG. 5  is a perspective of the mount of  FIG. 2  having the anti-cant indicator removed; 
         FIG. 6  is a perspective of the anti-cant indicator; 
         FIG. 7  is a section of the mount taken in a plane including  7 - 7  of  FIG. 2 ; and 
         FIG. 8  is a section of the mount taken in a plane including  8 - 8  of  FIG. 3 . 
     
    
    
     Corresponding reference numbers indicate corresponding parts throughout the drawings. 
     DETAILED DESCRIPTION 
     Referring to  FIG. 1 , a weapon aiming accessory (broadly, “anti-cant indicator assembly”) of the present disclosure is indicated generally by  10 . In the illustrated embodiment, the weapon aiming accessory  10  comprises a sight  12  (e.g., scope) and at least one mount  14  for mounting the sight on a weapon such as a firearm. The user aims the weapon by generally looking down a longitudinal sighting axis LSA to point a forward end (e.g., muzzle) of the weapon toward a target for aiming the weapon at the target. As explained in further detail below, the weapon aiming accessory  10  includes an anti-cant indicator  20  for indicating whether the weapon is canted with respect to vertical. 
     In the illustrated embodiment, two mounts  14 A,  14 B are provided. The first and second mounts  14 A,  14 B each comprise a sight connector  16  for connecting the sight  12  to the mounts. In the illustrated embodiment, the sight connectors  16  form rings for connecting the sight  12  to the mounts  14 A,  14 B. The mounts each include a main body  13  defining a first portion of the ring, and a secondary body  15  defining a second portion of the ring connectable to the main body by fasteners  17  (e.g., bolts) for forming the ring. The sight  12  is connected to the mounts  14 A,  14 B by locating respective portions of the sight between the ring portions and connecting the ring portions to each other with the fasteners  17 . Other types of sight connectors can be used without departing from the scope of the present disclosure. Moreover, the sight connectors may be omitted, and/or the sight may be formed integrally with the mounts. 
     The mounts  14 A,  14 B also each comprise a weapon connector  18  for connecting the mounts  14 A,  14 B and thus the sight  12  to the weapon. In the illustrated embodiment, the weapon connectors  18  comprise clamps configured to clamp to the weapon (e.g., to a dovetail rail of the weapon). A first jaw  18 A of the clamp is defined by the main body  13 . A second jaw  18 B is movable with respect to the first jaw  18 A and is connected to the main body  13  by a fastener  19  (e.g., bolt). The first and second jaws  18 A,  18 B can be drawn toward each other to decrease a space between the jaws to clamp on the rail of the weapon. In the illustrated embodiment, this is done by threading a nut  19 A onto the fastener  19  to push the jaws  18 A,  18 B toward each other. Other types of weapon connectors (e.g., other types of clamps, etc.) can be used without departing from the scope of the present disclosure. 
     As shown in  FIG. 1 , the first mount  14 A may be used to mount a rear portion of the sight  12  to a weapon, and the second mount  14 B may be used to mount a forward portion of the sight  12  to the weapon. The mounts  14 A,  14 B have respective forward end portions (facing to the right in  FIG. 1 ) and rearward end portions (facing to the left in  FIG. 1 ). The forward end portion of the rear mount  14 A faces toward the rearward end portion of the forward mount  14 B. In other words, the forward end portion of each mount  14 A,  14 B is arranged to be in front of the mount&#39;s rearward end portion when the mount  14 A,  14 B is mounted on the firearm. 
     In other embodiments, the sight connectors  16  may be connected (e.g., releasably connected or fixed) to a shared bracket (not shown) having one or more weapon connectors  18  for connecting the bracket and thus the sight  12  to the firearm. Other configurations can be used without departing from the scope of the present disclosure. 
     While aiming the weapon (e.g., looking generally down the longitudinal sighting axis LSA), the user may desire to know whether the weapon is canted with respect to vertical. To facilitate the user properly orienting the weapon, the assembly  10  includes the anti-cant indicator  20 . The anti-cant indicator  20  includes a mounting bracket  22  (broadly, mount or support), an arm  24  pivotably connected to the mounting bracket, and a level vial  26  supported by the arm. The arm  24  and vial  26  can be referred to broadly as a level. 
     The main body  13  defines anti-cant indicator support structure to which the mounting bracket  22  is connectable by two upper fasteners  28 A and two lower fasteners  28 B (e.g., bolts) passing through openings  30  in the mounting bracket  22 . The fasteners  28 B are threadably received in openings  32  in the main body  13 . 
     The arm  24  is pivotable with respect to the mount  14 A from a stowed position (e.g.,  FIGS. 2, 3 ) in which the arm extends upward, to an operational (e.g., deployed) position (e.g.,  FIG. 4 ) in which the arm extends laterally. The arm  24  is connected to the bracket  22  by a pivot connection. A proximal end of the arm  24  (defining a first pivot connector) is connected to the bracket  22  by a pin  36  extending through the arm and into two portions of the mounting bracket  22  (defining a second pivot connector) on opposite forward and rearward sides of the arm. The arm  24  is pivotable about a pivot axis PA defined by the pin  36 . The pivot axis PA extends in a rearward-to-forward orientation with respect to the arm  24  and the mount  14 A. The pivot axis PA is transverse to the longitudinal axis LA of the vial. Moreover, the pivot axis PA extends generally parallel with the longitudinal sighting axis of the weapon or sight  12  when the mount is mounted on the weapon. The arm  24  is pivotable about the pivot axis PA in a pivot plane extending transversely with respect to the longitudinal sighting axis of the weapon or sight  12 . Other arrangements can be used without departing from the scope of the present disclosure. 
     The anti-cant indicator  20  includes retaining structure (broadly, at least one retainer) on at least one of the arm  24  and/or the mounting bracket  22  configured to retain the arm in the stowed position and in the operational position. In the illustrated embodiment, arm  24  has a proximal end defining a first pivot connector, and the bracket  22  defines a second pivot connector. The retaining structure comprises two balls  40  (broadly, “detents”) captured in a bore in the arm  24  and biased in opposite directions by a spring  42  in the bore between the balls. The mounting bracket  22  includes two pairs of openings  46 A,  46 B (broadly, “retainer recess”). One pair of openings  46 A receives respective ones of the spring biased balls  40  in the stowed position. The other pair of openings  46 B receives the spring biased balls  40  in the operational position. The balls  40  when received in the openings  46 A,  46 B resist movement of the arm  24  out of the respective stowed or operational position. Application of force on the arm  24  tending to pivot the arm out of the stowed position toward the operational position can overcome the bias of the spring  42  (permitting the balls  40  to move inward, toward each other) to dislodge the balls from the openings  46 A and permit pivoting of the arm  24  to the operational position, where the balls are forced by the spring into the other pair of openings  46 B. Conversely, application of force on the arm  24  tending to pivot the arm out of the operational position toward the stowed position can overcome the bias of the spring  42  to dislodge the balls  40  from the openings  46 B and permit pivoting of the arm to the stowed position, where the balls are forced by the spring into the other pair of openings  46 A. 
     It will be appreciated that the pivot connection of the arm  24  permits the arm to be selectively moved between the stowed and operational positions. In the stowed position, the arm  24  is relatively streamlined with the bracket  22  and mount  14 A and is braced above the pivot connection by portions of the bracket  22  in front of and behind the arm. In the operational position, the arm  24  protrudes a greater amount from the bracket  22  and is viewable to the side of the sight  12  as the user looks generally down an aiming axis of the sight to aim the weapon. The pivot connection of the arm  24  to the mount  14 A is provided at a lateral side of the main body  13  below a top of the main body and above a bottom of the main body, such that in the operational position the arm (and the longitudinal axis LA of the vial) extends laterally away from the side of the main body in a space laterally of the sight connector  16  below the top of the sight connector and above the bottom of the sight connector, such that the bubble  50  is below the top of the mount. 
     Referring to  FIG. 4 , when the arm  24  is in the deployed position, the user can reference a bubble  50  (broadly, “anti-cant gauge”) in the level vial  26  to determine whether the weapon is oriented properly with respect to vertical. For example, if the bubble  50  in the level vial  26  is between two lines  52  (broadly, one or more “references”) on the level vial  26 , the anti-cant indicator  20  indicates the firearm is vertical (not canted). On the other hand, if the bubble  50  is not between the two lines  52 , the anti-cant indicator  20  indicates the firearm is canted and should be better oriented by the user for optimal performance of the weapon. 
     The anti-cant indicator  20  is adjustable to calibrate the anti-cant indicator  20  with respect to the mount  14 A and the particular weapon on which the aiming accessory  10  is mounted. The level vial  26  extends laterally along a level vial axis LA when the arm  24  is in the operational position. In some instances, the level vial axis LA may need to be adjusted to be square with respect to a vertical reference plane VP of the firearm so that the anti-cant indicator properly indicates cant of the firearm. To permit such adjustment, the mounting bracket  22  of the anti-cant indicator  20  is adjustably connected to the anti-cant indicator support structure of the main body  13 . The mounting bracket  22  and main body  13  include respective pivot engagement surfaces at which the mounting bracket and main body engage each other. In the illustrated embodiment, the mounting bracket  22  includes first and second ribs  60  defining respective male arcuate (broadly, “convex”) pivot engagement surfaces, and the main body includes a channel  62  defining a female arcuate (broadly, “concave”) pivot engagement surface. The ribs  60  are received in the channel  62 , and the mounting bracket  22  is pivotable with respect to the main body  13  by pivoting the mounting bracket  22  about the ribs received in the channel. To permit pivoting of the mounting bracket  22 , the fasteners  28 A,  28 B can be loosened (unthreaded). To maintain the mounting bracket  22  in a desired position, the fasteners  28 A,  28 B are tightened (threaded in). It will be appreciated that the channel  62  can be on the mounting bracket  22  and the rib  60  on the ring  16 , and other types of pivot engagement surfaces (or other types of pivot connections) can be used without departing from the scope of the present disclosure. 
     In one method of adjusting the anti-cant indicator  20 , the firearm is positioned in a vise so that the weapon is held securely in a non-canted orientation as can be determined by supporting a calibration level (not shown) on a surface (e.g., bolt ways) of the firearm known to have a horizontal orientation with respect to the firearm. When the firearm is in the non-canted orientation (as indicated by the calibration level), the anti-cant indicator  20  can be adjusted to calibrate for proper anti-cant indication. In particular, the upper and/or lower fasteners  28 A,  28 B can be loosened to permit the mounting bracket  22  to pivot with respect to the mount  14 A. Desirably, the mounting bracket  22  engages the main body  13  only at the pivot engagement surface  60  (within a range of pivoting) such that the mounting bracket is not obstructed from pivoting to calibrate the level vial axis LA. In one example, the lower fasteners  28 B are unthreaded, and then the upper fasteners  28 A are threaded in or out (and/or the bracket  22  or arm  24  is manually manipulated by the user) to cause the mounting bracket  22  to pivot about the engagement of the ribs  60  with the channel  62 . When the level vial axis LA is horizontal (e.g., bubble indicating no cant), the lower fasteners  28 B (and, if necessary, the upper fasteners  28 A) are threaded in to secure the anti-cant indicator  20  in the calibrated configuration. In the calibrated configuration, the fasteners  28 A,  28 B cause the ribs  60  of the mounting bracket  22  press against the channel  62  of the main body  13 , and the mounting bracket is otherwise slightly spaced from the main body. 
     It will be appreciated that the weapon aiming accessory can be referred to as an anti-cant indicator assembly. Although the illustrated embodiment is configured to mount a sight to a weapon, in other embodiments the anti-cant indicator assembly may not mount a sight to the weapon. For example, the anti-cant indicator assembly may mount only the anti-cant indicator to the weapon. 
     It will be apparent that modifications and variations are possible without departing from the scope of the invention defined in the appended claims. 
     As various changes could be made in the above constructions and methods without departing from the scope of the invention, it is intended that all matter contained in the above description and shown in the accompanying drawings shall be interpreted as illustrative and not in a limiting sense.