Patent Publication Number: US-11391533-B2

Title: Rifle bipod

Description:
TECHNICAL FIELD 
     This invention relates to a rifle bipod and an associated method of supporting a rifle. 
     BACKGROUND ART 
     The following discussion of the background art is intended to facilitate an understanding of the present invention only. The discussion is not an acknowledgement or admission that any of the material referred to is or was part of the common general knowledge as at the priority date of the application. 
     When shooting rifles and other firearms, especially in stressful tactical situations, it is important that the firearm be maintained in a steady, stable position to insure accuracy of aim. Most shooters are not able to hold a firearm consistently in a set position without wavering, especially after the onset of fatigue resulting from strain due to the size and weight of the firearm. Accordingly, peripheral support devices have been used in conjunction with firearms since the early creation of firearms as a means of stabilising a firearm to reduce vibration and wavering and to improve accuracy. 
     In the past, shooters have used everything from large stationary objects such as rocks and tree branches to forked sticks, shooting slings, bipods and tripods. Early bipod and tripod supports were typically somewhat crude stands that generally were bulky, inconvenient and difficult to use and typically were not easily adjustable. In more recent times, bipod supports have been developed that are compact and relatively lightweight and are mountable to the forearm stock of a firearm, such as a rifle, to make the bipods portable with the firearm. 
     As is known in the art, a bipod is an attachment, usually to a weapon, that helps support and steady it. The bipod generally provides significant stability along two axes of motion (side-to-side, and up-and-down). On firearms, bipods are commonly used on rifles and machine guns to provide a forward rest and reduce motion. They are also seen on other long-barreled weapons. Bipods permit operators to easily rest a weapon on objects, like the ground or a wall, reducing their fatigue and increasing accuracy and stability. Bipods can be of fixed or adjustable length. Some can be tilted and also have their tilting point close to the barrel&#39;s central axis, allowing the weapon to tilt left and right. 
     A problem with conventional bipods has been in allowing adjustability of the bipod to suit a shooter&#39;s preference, rather than the shooter having to compensate for shortcomings of the bipod. A further shortcoming with conventional bipods is that various surfaces on which a bipod can be rested can affect the stability thereof, leading to reduced accuracy from a firearm supported thereon. 
     The current invention was conceived with these shortcomings in mind. 
     SUMMARY OF THE INVENTION 
     Reference herein to a ‘rifle’ is to be understood to refer to any firearm, whether rifled or smoothbore, from which a projectile (bullet or otherwise) is dischargeable, when in use. Accordingly, the use of a bipod generally facilitates accurate and precise aiming of such a rifle, where the rifle is supportable on a variety of surfaces allowing a marksman or shooter to aim said rifle. 
     According to a first aspect of the invention there is provided a rifle bipod comprising: 
     a rifle support configured for operatively receiving and supporting a portion of a rifle; 
     two legs each having a tubular upper and lower portion telescopically arranged with an urging element operatively urging said portions into an extended position and having a cam lock arrangement configured to allow infinite length adjustability between the telescoping upper and lower portions, each leg further having a foot attachment configured to releasably receive interchangeable feet whereby each leg is operatively able to engage a surface; and 
     a stabilising arrangement pivotably attaching the legs to the rifle support at a commensurate off-vertical angle and having a biasing element configured to operatively bias both legs towards each other, and a linkage configured to maintain the off-vertical angle commensurate as the legs pivot apart, wherein the rifle support is height adjustable via the telescoping legs and the linkage maintaining the off-vertical angle commensurate whilst the feet are engaged with the surface. 
     In one example, the rifle support is configured to receive a rifle by defining a suitable rail attachment. 
     Typically, the rail attachment is selected from a group consisting of a Picatinny rail (also known as a MIL-STD-1913 rail), a Weaver rail, a NATO accessory rail, a Warsaw Pact rail, a UIT rail, KeyMod, M-LOK, or any other rail integration system. 
     Typically, the rail attachment includes a quick-release mechanism. 
     Typically, the rifle support is located at or proximate an apex of a triangle formed by the pivotally attached legs. 
     In one example, the rifle support is configured to receive and support a portion of a rifle such that a barrel of said rifle is above the apex. 
     Alternatively, the rifle support is configured to receive and support a portion of a rifle such that a barrel of said rifle is below the apex. 
     Typically, the lower portion of each leg is manufactured from titanium. 
     Typically, the urging element includes a spring, pneumatic and/or hydraulic biasing means arranged within the telescoping upper and lower portions. 
     In one example, an urging force provided by the urging element is selected according to a weight of a firearm to be supported by the bipod. 
     In one example, the urging element is configured so that an urging force thereof is user-configurable according to a weight of a firearm to be supported by the bipod. 
     Typically, the cam lock arrangement comprises an over-centre locking arrangement to secure the cam lock arrangement when locked. 
     Typically, the cam lock arrangement comprises a rotatable annulus eccentrically arranged about each leg and configured so that rotation of said annulus urges the eccentric annulus against the tubular portions to lock said telescoping portions in position with respect to each other. 
     In one example, the rotatable annulus comprises an internally interspaced pattern configured to complementarily receive and capture a pin defined on a leg to allow length adjustability between the telescoping upper and lower portions and/or lock a leg into an unextended or compressed position. 
     Typically, the foot attachment on each leg includes an interference-fit or press-fit attachment. 
     In one example, the interference-fit attachment includes a magnet to retain the feet therein. 
     In one example, the bipod includes interchangeable feet selected from a group consisting of claw feet, stake feet, magnetic attachment feet, and non-slip knob feet. 
     Typically, the stabilising arrangement is configured to allow the legs to be swivelled into a storage position wherein the legs lie longitudinally with a firearm received by the rifle support. 
     Typically, the biasing element comprises a spring configured to bias the legs towards each other. 
     In one example, the stabilising arrangement comprises an inverted triangular member with the rifle support fast at an upper side thereof so that the inverted triangular member points downwards, each leg pivotably attached at an upper vertex of said triangular member, the linkage comprising two links rotatably fast proximate the bottom vertex inside a vertically guiding slot and respectively fast to a leg below the upper vertex attachment, so that angling of the legs is facilitated by the bottom vertex attachment sliding within the guiding slot. 
     In one example, the linkage is configured to separate the legs at the off-vertical angle when the legs are attached to the triangular member. 
     Typically, the linkage includes a locking means configured to lock the linkage in position to maintain the commensurate off-vertical angle of the legs. 
     In one example, the locking means is configured to lock the bottom vertex attachment of the linkage in position in the vertical guiding slot. 
     In one example, the locking means comprises each link defining a rack and shared pinion arrangement, the pinion linked to a locking lever to allow the links to be locked in place via the locking lever. 
     In one example, each cam lock arrangement is linked to the locking means so that actuation of the locking means releases or locks each respective leg&#39;s cam lock arrangement and the linkage simultaneously. 
     Typically, the cam lock arrangement is linked to the locking means via a cable arrangement, said cam lock arrangement biased into a locking state with tension on a cable configured to counteract said bias and release the cam lock arrangement. 
     According to a second aspect of the invention there is provided a method of supporting a rifle, said method comprising the steps of: 
     attaching a rifle to the rifle bipod in accordance with the first aspect of the invention; and 
     adjusting a height of the rifle support to suit a shooting position of a shooter. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The description will be made with reference to the accompanying drawings in which: 
         FIG. 1  is a diagrammatic front-view representation of one embodiment of a rifle bipod, in accordance with an aspect of the invention; 
         FIG. 2  is a diagrammatic front-view representation of the rifle bipod of  FIG. 1 , showing the rifle support adjusted downwards; 
         FIG. 3  is a diagrammatic side-view representation of the rifle bipod of  FIG. 1 , showing the legs swivelled into a storage position; 
         FIG. 4  is a diagrammatic front-view representation of the stabilising arrangement of the rifle bipod of  FIG. 1 ; 
         FIGS. 5A and 5B  are diagrammatic front- and side-view representations of a further embodiment of a rifle bipod with a rifle support supporting a rifle below an apex of a triangle formed by the legs; 
         FIGS. 6A and 6B  are diagrammatic front- and side-view representations of a rifle bipod with locking means comprising each link having a rack and shared pinion arrangement with a shared locking lever; and 
         FIGS. 7A, 7B and 7C  are diagrammatic representations of different examples of cam lock arrangements of the bipod&#39;s legs. 
     
    
    
     DETAILED DESCRIPTION OF EMBODIMENTS 
     Further features of the present invention are more fully described in the following description of several non-limiting embodiments thereof. This description is included solely for the purposes of exemplifying the present invention to the skilled addressee. It should not be understood as a restriction on the broad summary, disclosure or description of the invention as set out above. In the figures, incorporated to illustrate features of the example embodiment or embodiments, like reference numerals are used to identify like parts throughout. 
     With reference now to the accompanying figures, there is shown one embodiment of a rifle bipod  10 . The exemplified embodiment of the rifle bipod  10  broadly comprises a rifle support  12 , two legs  14 , and a stabilising arrangement  30 . The bipod  10  is shown resting on a surface  28 . 
     The rifle support  12  is typically configured for operatively receiving and supporting a portion of a rifle  8  thereon and/or thereby. In the present example, the rifle support  12  is configured to receive a rifle (not shown) by defining a suitable rail attachment  13 , as shown. Typically, the rail attachment is selected from a group consisting of a Picatinny rail (also known as a MIL-STD-1913 rail), a Weaver rail, a NATO accessory rail, a Warsaw Pact rail, a UIT rail, KeyMod, M-LOK, or any other rail integration system. Typically, the rail attachment  13  includes a quick-release mechanism, as is known in the art. Similarly, other types of attachment are possible, e.g. threaded, press-fit, friction fit, etc., and are within the scope of the present invention. 
     Typically, the rifle support  12  is located at or proximate an apex of a triangle formed by the pivotally attached legs  14 . In one example, the rifle support  12  is configured to receive and support a portion of a rifle  8  such that a barrel of said rifle is above the apex. Alternatively, as shown in  FIG. 5 , the rifle support  12  can also be configured to receive and support a portion of a rifle  8  such that a barrel of said rifle is below the apex. This arrangement may have benefits concerning a lower centre of gravity of the bipod  10  with attached rifle  8  to allow ease-of-use. 
     The two legs  14  each typically comprises a tubular upper portion  16  and a lower portion  18  which have been telescopically arranged within each other, as shown. The lower portions  16  of each leg  14  are typically manufactured from titanium in one example, but the skilled addressee will appreciate that various other materials can be used for the constituent parts of the bipod  10 , depending on requirements, including steel, aluminium, polymer materials, and the like. 
     Each leg  14  also includes an urging element  20  that urges said portions  16  and  18  into an extended position, i.e. pushes them telescopically apart. The urging element is typically a spring or similar device. The skilled addressee will appreciate that the upper and lower portions  16  and  18  have been arranged such that a suitable detent or stop (not shown) prevents the upper and lower portions  16  and  18  from separating entirely, i.e. pull apart. 
     As mentioned, the urging element  20  typically includes a coiled spring arranged within the telescoping upper and lower portions  16  and  18 , but other configurations are possible, e.g. a compressible gas, or similar pneumatic or hydraulic arrangements, etc. In a typical example, an urging force provided by the urging element  20  is selected according to a weight of a firearm to be supported by the bipod  10 . In another example, the urging element  20  is configured so that an urging force provided thereby is user-configurable according to a weight of a firearm to be supported by the bipod, i.e. to allow firearms of various weights to be supported. 
     It is to be appreciated that by selecting an appropriate urging force for the urging element  20  generally allows a supported firearm to be suspended or create an impression with a shooter that the firearm ‘floats’ such that minor and effortless motions are required to alter the aim of such a firearm. 
     Each leg further includes a cam lock arrangement  22  which is generally configured to allow infinite length adjustability between the telescoping upper and lower portions  16  and  18 . This allows the upper and lower portions  16  and  18  to be adjusted along the entire length of motion provided by such telescopic arrangement to be locked in place according to a shooter&#39;s requirements. 
     One example of the cam lock arrangement  22  comprises an over-centre locking arrangement to secure the cam lock arrangement  22  when locked. The cam locking arrangement may also be configured to lock the cam lock arrangement  22  in a neutral position, so that during adjustment of the legs  14 , the cam lock arrangement  22  is positively in a position that allows the legs  14  to freely move, e.g. a ball and spring which fits into a suitable indent to locate the neutral position (example shown in  FIG. 7A ), a circlip or retaining ring arrangement, or the like. 
     Typically, the cam lock arrangement  22  comprises a rotatable annulus  60  eccentrically arranged about each leg  14  and configured so that rotation of said annulus urges the eccentric annulus against the tubular portions  16  or  18  to lock the telescoping portions  16  and  18  in position with respect to each other. The skilled addressee will appreciate that other locking arrangements are possible and within the scope of the present invention. 
     For example, with reference to  FIG. 7 , there are shown various types of potential locking arrangements  22 .  FIG. 7A  shows an example of an over-centre locking arrangement with a circlip-type biasing element  58 .  FIG. 7B  shows an example of a cam lock arrangement  22  which is linked to the locking means  50  (described in more detail below) via a cable arrangement  56 . 
       FIG. 7C  shows one example of the rotatable annulus  60  comprising an internally interspaced pattern  62 , such as the exemplified saw-tooth pattern  62 , configured to complementarily receive and capture a pin defined on a leg to allow infinite length adjustability between the telescoping upper and lower portions  16  and  18  and/or lock a leg into an unextended position. For example, the rotatable annulus  60  comprising an internally interspaced pattern  62  can be used similar to a retractable or ‘click’ pen so that when the rifle support  12  is pushed down to compress the legs, the annulus  60  captures a suitable pin to engage and lock the legs in a compressed or unextended position, i.e. minimum length. The bipod can then be folded back for stowing. If needed again, the rifle support  12  can be urged downward to disengage the pin from the annulus to again allow length adjustability of the legs. 
     Each leg  14  also typically includes a foot attachment  24  which is configured to releasably receive interchangeable feet  26  whereby each leg is operatively able to engage a surface  28 . Typically, the foot attachment  24  on each leg  14  includes a press-fit attachment, i.e. having a somewhat elastic nylon ring into which a foot  26  can be pressed and held in place, or a dowel pin configured to engage a suitable aperture in the foot attachment, a magnet to retain the feet therein, etc. Other configurations are possible and within the scope of the present invention. A variety of feet  26  are possible according to requirements, including rubber ball feet, pointed feet, claw feet, stake feet, magnetic attachment feet for securing the bipod to a magnetic surface, non-slip knob feet, etc. Some feet  26  may be able to swivel via a suitable ball-and-socket configuration, where other feet  26  may be fixed, or the like. 
     The rifle bipod  10  further includes a stabilising arrangement  30  which is configured to pivotably attach the legs  14  to the rifle support  12  at a commensurate off-vertical angle  32 , as shown. Reference to such off-vertical angle  32  refers to the angle formed by each leg with the vertical, as indicated. Similarly, the stabilising arrangement  30  is configured to substantially maintain the angle  32  of each leg the same or commensurate with the other, as described in more detail below. 
     The stabilising arrangement  30  includes a biasing element  34  which is configured to operatively bias both legs  14  towards each other, such as a coiled or leaf spring configured to bias the legs  14  towards each other. Accordingly, when there is no downward force, such as the weight of a rifle supported by the rifle support  12 , acting on the legs  14 , the legs  14  will be maintained in a particular off-vertical angle  32 , an example of which is shown in  FIG. 1 . Conversely, when a downward force acts upon the legs  14 , the legs  14  can shorten via the telescoping upper and lower portions  16  and  18  such that the off-vertical angle  32  increases, as shown in  FIG. 2 . 
     The stabilising arrangement  30  further includes a linkage  36  which is configured to maintain the off-vertical angle  32  commensurate as the legs  14  pivot apart, so that the rifle support  12  is height adjustable closer to, or further away from, the surface  28  via the telescoping legs  14  and the linkage  36  maintaining the off-vertical angle  32  similar or commensurate whilst the feet  26  are engaged with the surface  28 . 
     As shown in  FIG. 3 , the stabilising arrangement  30  is typically configured to allow the legs  14  to be swivelled into a storage position wherein the legs  14  lie longitudinally with a firearm received by the rifle support  12 . 
       FIG. 4  shows a closer view of one example of the stabilising arrangement  30  which comprises an inverted triangular member  38  with the rifle support  12  fast at an upper side  40  thereof. In such a configuration, the inverted triangular member  38  points downwards, as shown, with each leg  14  pivotably attached at an upper vertex  42  of the triangular member  38 , as shown. The linkage  36  comprises two links  44  rotatably fast proximate the bottom vertex  46  inside a vertically guiding slot  48  with each link  44  respectively fast to a leg  14  below the upper vertex attachment  42 . In this manner, angling (via pivoting) of the legs  14  is facilitated by the bottom vertex attachment  46  sliding up and down within the guiding slot  48 , as will be apparent to the skilled addressee. 
     In one example, the linkage  36  is configured to separate the legs  14  at the off-vertical angle  32  when the legs are attached to the triangular member  38 . In such an example, a length of each link  44  determines the off-vertical angle  32  when there is no incident downward force applied to the rifle support  12 , as described above. In one example, the bottom vertex attachment  46  also includes a locking means  50 , such as a bolt or nut, wingnut, etc., configured to lock the bottom vertex attachment  46  of the linkage  36  in position in the vertical guiding slot  48 . Such locking means  50  locks the legs  14  in a particular off-vertical angle  32 , as per requirements. 
     In use, a shooter attaches a rifle to the bipod  10  via the rifle support  12 . The legs  14  are able to lengthen or shorten whilst the stabilising arrangement  30  facilitates in maintaining the off-vertical angle  32  of the legs  14 , as well as maintaining the rifle support  12  substantially horizontal. 
     In a further example, shown in  FIG. 6 , the locking means  50  comprises each link  44  defining a rack and shared pinion arrangement  52 , with this shared pinion linked to a locking lever  54  to allow the links  44  to be locked in place via the locking lever  54 . In one example, each cam lock arrangement  22  is linked to the locking means  50  so that actuation of the locking means releases or locks each respective leg&#39;s cam lock arrangement  22  and the linkage  36  simultaneously. In the example of  FIG. 7B , the cam lock arrangement  22  is linked to the locking means  50  via a cable arrangement  56 , wherein the cam lock arrangement  22  is biased into a locking state by bias spring  58  with tension on a cable  64  configured to counteract said bias and release the cam lock arrangement  22 . Other variations hereon as possible and within the scope of the present invention. 
     Accordingly, embodiments are possible wherein a user is required to actuate each respective lock arrangement  22  for each leg, as well as the locking means  50  to locks the legs  14  in a particular off-vertical angle  32 , as per requirements. Similarly, the bipod  10  can be configured with a single locking lever  54  or the like, whereby each respective lock arrangement  22  for each leg and the locking means  50  can be simultaneously actuated. Variations hereof are possible and within the scope of the present invention. For example, the locking lever  54  may be linked to the linkage via a gear or gears to lock the linkage in place, or the like. 
     The skilled addressee will further appreciate that the present invention also includes an associated method of supporting a rifle. Such a method typically comprises the steps of attaching a rifle  8  to the rifle bipod  10  and adjusting a height of the rifle support  12  to suit a shooting position of a shooter. 
     Applicant believes is particularly advantageous that the present invention provides for a rifle bipod  10  that allows infinite adjustability of the legs  14  via the cam lock arrangement  22 . It is further believed to be advantageous that the stabilising arrangement  30  maintains the off-vertical angle of each leg  14  commensurate to facilitate in allowing the feet  26  of the bipod  10  to engage with a surface  28  that may be angled and/or uneven such that the rifle support  12  is maintained substantially level to facilitate aiming of a rifle supported thereby. 
     Optional embodiments of the present invention may also be said to broadly consist in the parts, elements and features referred to or indicated herein, individually or collectively, in any or all combinations of two or more of the parts, elements or features, and wherein specific integers are mentioned herein which have known equivalents in the art to which the invention relates, such known equivalents are deemed to be incorporated herein as if individually set forth. In the example embodiments, well-known processes, well-known device structures, and well-known technologies are not described in detail, as such will be readily understood by the skilled addressee. 
     The use of the terms “a”, “an”, “said”, “the”, and/or similar referents in the context of describing various embodiments (especially in the context of the claimed subject matter) are to be construed to cover both the singular and the plural, unless otherwise indicated herein or clearly contradicted by context. The terms “comprising,” “having,” “including,” and “containing” are to be construed as open-ended terms (i.e., meaning “including, but not limited to,”) unless otherwise noted. As used herein, the term “and/or” includes any and all combinations of one or more of the associated listed items. No language in the specification should be construed as indicating any non-claimed subject matter as essential to the practice of the claimed subject matter. 
     It is to be appreciated that reference to “one example” or “an example” of the invention, or similar exemplary language (e.g., “such as”) herein, is not made in an exclusive sense. Various substantially and specifically practical and useful exemplary embodiments of the claimed subject matter are described herein, textually and/or graphically, for carrying out the claimed subject matter. 
     Accordingly, one example may exemplify certain aspects of the invention, whilst other aspects are exemplified in a different example. These examples are intended to assist the skilled person in performing the invention and are not intended to limit the overall scope of the invention in any way unless the context clearly indicates otherwise. Variations (e.g. modifications and/or enhancements) of one or more embodiments described herein might become apparent to those of ordinary skill in the art upon reading this application. The inventor(s) expects skilled artisans to employ such variations as appropriate, and the inventor(s) intends for the claimed subject matter to be practiced other than as specifically described herein.