Patent Publication Number: US-11644281-B2

Title: Lever based clamping device

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application is a continuation of U.S. patent application Ser. No. 16/270,452 filed Feb. 7, 2019, which claims the benefit of U.S. Provisional Patent Application No. 62/663,509 filed Apr. 27, 2018 entitled Lever Based Clamping Device. 
    
    
     BACKGROUND OF THE INVENTION 
     The present invention relates to a dual clamping device. More specifically, a dual clamping device that works in conjunction with commonly available dovetail brackets for imaging devices and commonly available accessory rails for rifles. 
     A Picatinny rail, also known as a MIL-STD-1913 rail, or Standardization Agreement 2324 rail, or also generally a NATO Accessory Rail referred to as STANAG 4694, is a bracket on some firearms that provides a mounting platform consisting of rails with multiple transverse slots. Referring to  FIG.  1   , the dimensions of the NATO Accessory Rail are illustrated. The Picatinny rail is designed to mount heavy sights and other attachments to the upper, side, or lower surfaces of all manner of weapons from crossbows to pistols and long arms up to and including anti-materiel rifles. The Picatinny rail consists of a strip undercut to form a flattened T cross-section provided with crosswise slots at intervals interspersed with flats that allow accessories to be slid into place from the end of the rail then locked in place; slid into the slots between raised flats then moved a short distance back or forth or clamped to the rail with bolts, and thumbscrews or levers. The Picatinny locking slot width is 0.206 in (5.23 mm). The spacing of slot centers is 0.394 in (10.01 mm) and the slot depth is 0.118 in (3.00 mm). 
     Referring to  FIG.  2   ,  FIG.  3   , and  FIG.  4   , a NATO Picatinny Dovetail Adapter is illustrated. The adapter includes a body  100  with a clamp  110  that is movable with respect to the body  100 . A set of three threaded screws  120 , each of which may include a countersunk head  130 , is rotatably interconnected with matching threads on the body  100 . By rotation of the threaded screws  120 , the clamp  110  is moved laterally with respect to the body  100 . The body  100  defines a pair of dovetail groves  140  that fit arca-swiss style clamps. 
     Referring also to  FIG.  5   , the three screws  120  are loosened using a hex key until the jaw is fully opened. The body  100  is installed onto the rail  150  by aligning the screws with the slots in the rail. Each of the screws  120  are lightly tightened, and then further tightened using a hex key. Referring to  FIG.  6   , with the adapter securely affixed to the rail  150 , a quick release clamp  160  may be detachably attached to the dovetail grooves  140  to support the firearm on a tripod. 
     Unfortunately, when the firearm is not being used with a compatible clamp the shooter may desire to remove the adapter from the firearm in an efficient manner which is a burdensome task. Also, the clamp that is detachably secured to the adapter tends to permit the firearm to slide within the clamp if not sufficiently secured in an efficient manner. 
     The foregoing and other objectives, features, and advantages of the invention may be more readily understood upon consideration of the following detailed description of the invention, taken in conjunction with the accompanying drawings. 
    
    
     
       BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS 
         FIG.  1    illustrates a NATO Accessory Rail. 
         FIG.  2    illustrates a top perspective view of a NATO Picatinny Dovetail Adapter. 
         FIG.  3    illustrates a bottom perspective view of the NATO Picatinny Dovetail Adapter of  FIG.  2   . 
         FIG.  4    illustrates a bottom view of the NATO Picatinny Dovetail Adapter of  FIG.  2   . 
         FIG.  5    illustrates the NATO Picatinny Dovetail Adapter of  FIG.  2    being attached to a Picatinny rail. 
         FIG.  6    illustrates the NATO Picatinny Dovetail Adapter of  FIG.  2    attached to a Picatinny rail. 
         FIG.  7    illustrates a tripod. 
         FIG.  8    illustrates an embodiment of a clamp assembly suitable to alternatively connect a dovetail plate of a camera or a Picatinny rail. 
         FIG.  9    illustrates an exploded view of clamp assembly of  FIG.  8   . 
         FIG.  10    illustrates a compression assembly of the clamp assembly of  FIG.  8   . 
         FIG.  11    illustrates an exploded view of a portion of the clamp assembly of  FIG.  8   . 
         FIG.  12    illustrates a lever portion of the clamp assembly of  FIG.  8   . 
         FIG.  13    illustrates a base portion of the clamp assembly of  FIG.  8   . 
         FIG.  14    illustrates a base view of the clamp assembly of  FIG.  8   . 
         FIG.  15    illustrates a view of the adjustment arm of the clamp assembly of  FIG.  8   . 
         FIG.  16    illustrates another view of a portion of the clamp assembly of  FIG.  8   . 
         FIG.  17    illustrates a view of a portion of the clamp assembly shown in  FIG.  8   . 
         FIG.  18    illustrates an exploded view of a portion of the clamp assembly of  FIG.  8   . 
     
    
    
     DETAILED DESCRIPTION OF PREFERRED EMBODIMENT 
     Referring to  FIG.  7   , in many situations it is desirable to have a stable, yet portable, support to permit a shooter to reliably take long and extreme long distance shots (e.g., even beyond 1,000 yards). In many cases, it is desirable that the support is suitable for positioning a rifle of a shooter over two feet or more from the ground, preferably over three feet or more from the ground, and preferably at a height consistent with a standing position of the shooter from the ground. By positioning the support at an elevated height, the shooter is able to shoot over most obstacles without meaningfully compromising the stability of the system or otherwise meaningfully diminishing accuracy. One suitable type of support is a tripod that includes three legs, each of which may be moved inward and outward along an arc from an upper central region. In addition, each of the legs has an adjustable length so that the upper region may be leveled or otherwise oriented in any desired orientation. In addition, the upper region typically includes a threaded member, or otherwise, suitable to be attached to the base of an imaging device or a ball head. An exemplary tripod is illustrated in U.S. Pat. No. 8,398,037, incorporated by reference herein in its entirety. Other supports include, for example, a monopod or a bipod. 
     Referring to  FIG.  8   ,  FIG.  9   ,  FIG.  10   , and  FIG.  11   , a clamp assembly  200  is preferably detachably interconnected to a support or otherwise a ball head. The clamp assembly  200  includes a body  210  (see also  FIG.  13   ) and an adjustable arm  212  (see also  FIG.  11   ,  FIG.  16   , and  FIG.  17   ) that together form an upper channel  214  having upper opposed side walls  216  and  218 . The upper channel  214  may include a pair of opposing supporting surfaces, which are part of the body  210  and/or part of the adjustable arm  212 . Preferably, at least one of the supporting surfaces of the upper channel  214  extends more than half of the width of body  210  and is preferably substantially centered with respect to the adjustable arm  212 . The body  210  may define an opening  220  through which the clamp  200  may be secured to the upper portion of a tripod or other support. Referring also to  FIG.  14   , the base of the body  210  may include a tongue and groove interface to facilitate it to key the rotation of the clamp relative to a support, such as a ball head. Alternatively, the base of the body may include a planar surface suitable for a support having a flat upper surface. Alternatively, the base and/or the adjustable arm may define a lower pair of dovetail grooves for attachment to a suitable clamp. Referring also to  FIG.  16    and  FIG.  17   , the adjustable arm  212  is slidably engaged along a stud  222  which is secured to a corresponding compression assembly  224  maintained within a cavity  250  (see  FIG.  15   ) in the adjustment arm  212 . The stud  222  is secured to a lever  226  together with a pin  252  extended through the stud  222  together with a washer  228 , and arranged through an external opening  231  (see  FIG.  11   ) in the base  210  and an external opening  250  in the adjustable arm  212  (see  FIG.  16   ). The end of the stud  222  is secured to the compression assembly  224  in the adjustable arm  212 . Rotation of the lever  226  selectively adjusts the width of the upper channel  214  and is accomplished through manual operation of the lever  226  fastened to the distal end of the stud  222 . Alternatively, the adjustable spacing may be achieved with any other suitable structure. By way of example, one exemplary ball head is illustrated in U.S. Patent Publication No. 2006/0175482, incorporated by reference herein in its entirety. 
     The lever  226 , operably attached to the adjustable arm  212 , permits adjustment of the spacing between the side walls  216  and  218  so that the upper channel may selectively either grip or release a pair of grooves attached to a camera body (not shown). An exemplary set of grooves attached to a camera body is illustrated in U.S. Pat. No. 9,298,069, incorporated by reference herein in its entirety. Each respective side wall  216  and  218  is preferably angled upward and inward to facilitate engagement with such grooves. In this manner, photographic equipment may be quickly engaged or released from the clamp assembly by using the upper channel. 
     A pair of springs  230  and  232  may be interconnected between the body  210  (preferably retained in a depression) and the adjustable arm  212  (preferably retained in a depression) so that an outwardly directed force is exerted between the body  210  and the adjustable arm  212  to assist in maintaining the adjustable arm  212  in a suitable position. Other structures may be included that operably tend to exert an outward force on the adjustment arm with respect to the body. By way of example, the upper channel  214  may define a minimum channel that is generally a maximum of about 41 millimeters wide at the inside of the channel, generally about a minimum of 34 millimeters wide at the top of the side walls  216  and  218 , with a height of generally about 4 millimeters, and an angle of substantially 45 degrees. Other channel sizes and structures may be used to correspond with the desired support structure for an imaging device. 
     In many situations, it is desirable to remove the camera being used to capture images of a scene from the clamp assembly and support a firearm together with a scope thereon to obtain a sharpened view of the particular scene. In many cases, the firearm includes a Picatinny rail on the lower surface thereof. To facilitate interconnection of the clamp assembly to the Picatinny rail, the clamp assembly preferably includes a lower channel, at an elevation lower than the upper channel, suitable for detachably interconnecting with the Picatinny rail. 
     The clamp assembly  200  includes the body  210  and the adjustable arm  212  that together form a lower channel  300  having lower opposed side walls  302  and  304 . The lower channel  300  may include a supporting surface which is primarily defined by the body  210  and a portion of which may be defined by the adjustable arm  212 , if desired. Preferably, the supporting surface of the lower channel  300  extends the width of body  210 . The adjustable arm  212  is slidably engaged along the stud  222  which is secured to the corresponding compression assembly  224  in the adjustable arm  212 . Movement of the adjustable arm  212  selectively adjusts the width of the lower channel  300  and is accomplished through manual operation of rotating the lever  226  fastened to the distal end of the stud  222 . The lever  226 , attached to the adjustable arm  212 , permits adjustment of the spacing between the side walls  302  and  304  so that the lower channel may selectively either grip or release one or more rails attached to the base of a firearm. Each respective side wall  302  and  304  includes a portion of which is preferably angled upward and inward to facilitate engagement with such rails. The lower channel  300  also preferably defines a raised central portion, which may be defined by the stud  222  or any other structure, which preferably has a width suitable to be positioned between a pair of rails of the Picatinny rail. In this manner, the raised central portion will tend to inhibit the clamp sliding with respect to the Picatinny rail because the raised central portion will come into contact with one of the rails of the Pictinny rail. The adjustment mechanism may be achieved using an off-centered shaft, and may be more than one off-centered shafts and/or one or more centered shafts. Preferably, the shaft occupies the same region of space as the Picatinny clamp. The shaft may be positioned beneath the lower channel, if desired. As described, the shaft which is preferably part of the adjustment arm adjustment mechanism may be used to engage the grooves of the Picatinny clamp to prevent shifting of the clamp under loaded conditions. Alternatively, other structures may be used for engagement with the grooves of the Picatinny clamp, such as one or more pins or protruding features. In this manner, firearms may be quickly engaged or released from the clamp assembly by using the lower channel. 
     Referring to  FIG.  18   , the compression assembly  224  may include one or more compression members  280 , such as Belleville spring washers and/or disc springs. The amount of compression may be varied by changing the orientation of one or more of the compression members  280 . The compression members  280  may be maintained on a threaded end member  282  by a resilient rubber washer  284  maintained in a groove  286 . The compression assembly  224  may be maintained centered within the cavity  250  by another resilient rubber washer  288  maintained within another groove  290 . In this manner, the compression assembly  224  includes one or more compression members that are centered on the compression assembly  224  while being aligned with the stud  222  and the compression assembly  224  is centered within the cavity  250  while being aligned with the stud  222 . 
     The lever  226  is preferably a cam lever that includes a cam portion that rotates about a pivot axis as the cam lever is moved between a first, unlocked position, and a second, locked position. The cam portion has an asymmetrical shape about the pivot axis so that the lever pulls the adjustable arm inward as the lever is moved from a first position for releasing equipment from the clamp to a second position for gripping equipment to the clamp. Conversely, as the lever is moved from the second position to the first position, the pair of counterforce springs, housed within the body, push outward on the adjustable arm so that the channel expands. 
     The outwardly directed force applied by the springs on the adjustable arm is at a maximum when the lever is in the second position, i.e. when the channel is intended to grip equipment. The force applied by the springs therefore acts to undesirably loosen the grip on the equipment. The clamp, however, includes the compression assembly that prevents any outward movement of the adjustable arm that might otherwise result from the force applied by the springs. The compression assembly may preferably apply an inwardly-directed force on the adjustable arm that increases as the lever is moved from the first position towards the second position. The inward force applied on the adjustable arm by the compression assembly may preferably be greater than the outward force applied by the springs when the lever is in the second position. Also, the lever may preferably include an over-center detent position. 
     The lever in the first position, i.e. the released position the adjustable arm is spaced apart from the body by an applied force from the springs, thus widening the channel to allow the insertion or removal of equipment. The cam portion is oriented such that the compression assembly, which in this instance is a series of Belleville springs that act as a compression spring, is sufficiently relaxed so as to not apply a sufficient inward force on the adjustable arm to overcome the outward force of the springs. In this position, the cam portion preferably abuts the adjustment arm at a minimum distance from the pivot axis. As the lever is moved from the first position toward the second position, the cam portion pulls the compression assembly and the adjustable arm, inward. The compression assembly begins to compress to counterbalance the outward force of the springs applied to the adjustable arm as it moves inward. 
     In a first intermediate position where the lever has been moved to a position where the adjustable arm is flush with the body, the forces applied by the compression assembly and the springs counterbalance each other; further movement of the lever towards the second position, however causes the inward force applied by compression of the compression assembly to increase over that of the springs because the adjustable arm may not move any further while the compression assembly will continue to compress. 
     In a second intermediate position where the compression assembly is applying a maximum inward force on the adjustable arm where the cam portion preferably pulls the compression assembly at a maximum distance from the pivot axis. In this position, the inward force applied by the compression assembly to the adjustable arm is substantially greater than the outward force applied by the springs. Further movement of the lever toward either the first or second position will relax the compression assembly with respect to the maximum inward force as the distance from the pivot axis on which the compression assembly abuts the cam portion decreases. 
     In the second position, the lever is in an over-center detent configuration such that movement of the lever toward the first position will act to compress the compression assembly. Thus, the compression assembly resists movement of the lever toward the first position. Preferably, when in this position, the inward force applied by the compression assembly to the adjustable arm is still greater than the outward force applied by the springs. Alternatively, the two forces could be precisely counterbalanced. In this manner, the adjustable arm is locked into place because the springs do not apply a sufficient force to overcome that force applied by the compression assembly. 
     The compression assembly preferably applies a force to the adjustable arm and the lever that varies with the position of the lever. The force preferably increases as the lever is moved from the first position towards the second position. The force preferably reaches a maximum before the lever reaches the second position. More preferably, the force applied by the compression assembly is less than that maximum when in the second position, so that the force applied by the compression assembly also increases as the lever is moved from the second position towards the first position. As the lever is moved over a range of motion extending from the first position to the second position, the force increases to a maximum at a second intermediate position and then decreases as the lever continues to the second position. 
     The adjustable arm may cease its inward motion at a first intermediate position before the compression assembly has reached its maximum force. This may be preferable so that the inward force applied by the compression assembly on the adjustable arm, when the lever is in the second position, can still overcome the outward force applied by the springs even though the force applied by the compression assembly has fallen from its maximum. It should be further noted that the movement of the adjustable arm corresponds to the movement of the lever. Therefore, it is desirable that the lever move through a large percentage of its range of motion before the adjustable arm ceases to move, and achieve a maximum force in the remaining range of motion of the lever. For that reason, the force applied by the compression assembly in the clamp achieves its maximum value at approximately 80-90% of the lever&#39;s range of motion. It should be understood, however, that other embodiments may achieve a maximum force anywhere along the lever&#39;s range of motion, but preferably greater than 50%. 
     As the lever is moved from the first position, the force increases continuously to a maximum and decreases continuously until the lever reaches the second position. Alternative embodiments may design a lever that permits the force profile to decrease at certain intervals on the lever&#39;s path from the first position to the second intermediate position of maximum force, or to increase on the lever&#39;s path from that second intermediate position to a lesser force at the second position, or both. Preferably, however, the force profile is increasing over at least 65% of the lever&#39;s path from the first position to the second intermediate position and is decreasing over at least 65% of the path from the second intermediate position to the second position. 
     As previously described, the clamp assembly  200  with a “stationary” body together with a moving adjustment arm defines the upper clamp that is preferably compatible with Really Right Stuff™ and Arca-Swiss style dovetails. As previously described, the clamp assembly  200  with a “stationary” body together with a moving adjustment arm defines the lower clamp that is preferably compatible with the Pictinny rail. With separate structures at different elevations within the same clamp assembly facilitates a compact clamp assembly that defines a pair of adjustable spacing structures. 
     The lever  226  of the clamp assembly  200  may be rotated in a clockwise direction to engage the jaws of the clamp assembly  200  to secure a device therein. Also, lever  226  of the clamp assembly  200  may be rotated in a counter-clockwise direction to engage the jaws of the clamp assembly  200  to secure a device therein. The capability of rotating the lever  226  selectively in either a clockwise or a counter-clockwise direction to engage the jaws of the clamp assembly  200  permits the user to select the direction of rotation that is most comfortable for them. In addition, the capability of rotating the lever  226  selectively in either a clockwise or a counter-clockwise direction accommodates users regardless of whether they are right hand dominant or left hand dominant. 
     In another embodiment, the lever may be omitted if desired. The lever would be replaced with a rotational member, such as a screw. In this manner, the clamp assembly may secure a device therein by rotation of the screw in a first direction (e.g., clockwise) and may detach a device therein by rotation of the screw in a second direction (e.g., counter-clockwise). 
     The terms and expressions which have been employed in the foregoing specification are used therein as terms of description and not of limitation, and there is no intention, in the use of such terms and expressions, of excluding equivalents of the features shown and described or portions thereof, it being recognized that the scope of the invention is defined and limited only by the claims which follow.