Patent Publication Number: US-8978285-B1

Title: Anti-rattle collapsible buttstock

Description:
TECHNICAL FIELD 
     The invention relates generally to buttstocks for attachment to firearms, and more particularly to a buttstock assembly that has an improved slide lock mechanism which provides an anti-rattle assembly. 
     BACKGROUND 
     For several military applications and/or operational groups, weapons may need to be collapsible for ease of transportation to a field venue, and then easily assembled in the field. For example, rifles are frequently designed to be collapsible. One typical portion of a collapsible rifle assembly is the buttstock that forms the aft-most part of the assembled rifle, which is received and covers a recoil absorption appendage, or “receiver extension.” In general, modern conventional buttstocks are ergonomic since the buttstock forms the interface with the user&#39;s shoulder area, and adjustable along the receiver extension to further form fit the rifle to the user. One manner in which modern conventional buttstocks are made adjustable is via a slide lock mechanism, which provides a biasing pin that fits into a retaining feature, such as a pin seat or hole, provided along the receiver extension. A number of such pin seats or holes are so provided by the receiver extension to provide multiple adjustment points which are used to either lengthen or shorten the rifle as a user may desire. 
     SUMMARY 
     In one embodiment, an apparatus for an anti-rattle assembly for a collapsible buttstock for a firearm may include a baseplate with a plurality of lower guides and a plurality of fasteners wherein the plurality of fasteners removably secure the anti-rattle assembly to a plurality of fastener positions of a buttstock body. The anti-rattle assembly may further include a pressure plate with one or more ridges to engage one or more rail surfaces of a receiver extension and a plurality of upper guides and a plurality of biasing members wherein the pressure plate is vertically aligned with the baseplate and the plurality of biasing members are coupled between the upper guides and the lower guides and bias the one or more ridges against the one or more rail surfaces. The anti-rattle assembly restricts the movement of the receiver extension in a tubular aperture of the buttstock body. 
     In another embodiment, an apparatus for a collapsible buttstock assembly may include a receiver extension, a buttstock body, and an anti-rattle assembly. The receiver extension may include an outer an alignment rail extending longitudinally along the receiver extension and comprising an elongated slot with a plurality of cavities spaced apart at regular intervals and one or more rail surfaces spanning a length of the alignment rail wherein each rail surface is situated on either side of the plurality of cavities. The buttstock body may include a body axis that runs longitudinally from a first end to a second end, and a tubular aperture with a tubular axis and a groove parallel with the tubular axis and is situated along an outer tube wall of the tubular aperture, the tubular axis is parallel to the body axis, and wherein the tubular axis receives the receiver extension. The buttstock body may further include a locking pin situated in a pin aperture with a pin axis that orthogonally penetrates the groove and wherein the locking pin in the extended position engages a cavity of the plurality of cavities and restricts the movement of the receiver extension, and a pin biasing spring that biases the locking pin into the groove. The buttstock body may further include a lever coupled to the locking pin wherein when the lever is actuated in a first direction, the locking pin is in retracted position and when the lever is in a resting state, the locking pin is in an extended position, and a plurality of fastener positions located around a perimeter wall of a rattle aperture. 
     In yet another embodiment, a method for reducing movement in a collapsible buttstock may include applying pressure on a receiver extension inserted into a tubular aperture of a buttstock body by using the anti-rattle kit. The method of reducing movement may further include aligning an upper tube portion of the receiver extension with an upper body portion of the tubular aperture with the applied pressure to reduce the movement of the buttstock body in relation to the receiver extension, and maintaining the alignment a tubular axis of the buttstock body with a firearm axis. The anti-rattle kit may include a baseplate with a plurality of lower guides and a plurality of fasteners wherein the plurality of fasteners removably secure the anti-rattle assembly to a plurality of fastener positions of the buttstock body, a pressure plate with one or more ridges to engage one or more rail surfaces of the receiver extension and a plurality of upper guides, and a plurality of biasing members wherein the pressure plate is vertically aligned with the baseplate and the plurality of biasing members are coupled between the upper guides and the lower guides and bias the one or more ridges against the one or more rail surfaces. 
     These and other features, aspects, and advantages of the present invention will become better understood with reference to the following description and the appended claims. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The embodiments set forth in the drawings are illustrative and exemplary in nature and not intended to limit the subject matter defined by the claims. The following detailed description of the illustrative embodiments can be understood when read in conjunction with the following drawings, where like structure is indicated with like reference numerals and in which: 
         FIG. 1  depicts a firearm with a collapsible buttstock according to one or more embodiments shown and described herein; 
         FIG. 2  depicts the receiver extension according to one or more embodiments shown and described herein; 
         FIG. 3  depicts the components of an anti-rattle assembly according to one or more embodiments shown and described herein; 
         FIG. 4A  depicts a right side view of the anti-rattle assembly in relation to a buttstock body according to one or more embodiments shown and described herein; 
         FIG. 4B  depicts a front view of the anti-rattle assembly in relation to a buttstock body according to one or more embodiments shown and described herein; 
         FIG. 5A  depicts a cross-section view taken along line  5 A- 5 A shown in  FIG. 1 , of the anti-rattle assembly within a rattle aperture within the buttstock body according to one or more embodiments shown and described herein; 
         FIG. 5B  depicts a close-up section view shown in  FIG. 5A , of the anti-rattle assembly within a rattle aperture within the buttstock body according to one or more embodiments shown and described herein; and 
         FIG. 5C  depicts a cross-section view taken along section line  5 B- 5 B shown in  FIG. 1 , of the anti-rattle assembly within a rattle aperture within the buttstock body according to one or more embodiments shown and described herein. 
     
    
    
     DETAILED DESCRIPTION 
     An anti-rattle assembly may be used in any type of collapsible firearm stock to reduce the play between a receiver extension of the firearm and a buttstock assembly that is slideably coupled to the receiver extension. The anti-rattle assembly may be mounted to the buttstock assembly and apply pressure to the receiver extension to reduce and/or eliminate any freedom of movement between the receiver extension and the buttstock assembly. The reduction and/or elimination of movement between the receiver extension and the buttstock assembly will reduce and/or eliminate noise from contact between the receiver extension and the buttstock assembly when the firearm is not under tension (e.g. not shouldered and/or in preparation to fire the firearm). In other words, when the firearm is being carried and/or moved, a noise or a rattle may emanate from contact between the receiver extension and buttstock assembly. In the field, such unwanted noise can be to a user&#39;s disadvantage by disclosing presence and/or position of the user to an adversary. Alternatively, when the firearm is under tension, (e.g. the firearm is shouldered) the freedom of movement between the receiver extension and buttstock assembly may affect a proper sight picture with a target. In other words, the gaps or space between the receiver extension and the buttstock may allow for the collapsible firearm stock to bend and/or deflect at an interface between the receiver extension and the buttstock assembly thereby allowing for an improper alignment of a user&#39;s line of sight with the sights on the firearm for a proper sight picture. As such, it is to be understood that the particular embodiment shown and described herein is merely one example of a suitable firearm and buttstock assembly, and that a firearm and/or buttstock assembly of any other type, kind, configuration, construction and/or arrangement in accordance with the subject matter of the present disclosure could alternately be used. 
     Referring now to  FIG. 1 , a firearm  100  is shown with a collapsible buttstock  105 . The collapsible buttstock  105  may have a buttstock assembly  110  and a receiver extension  115 . The receiver extension  115  may slideably couple with the buttstock assembly  110 . In other words, the receiver extension  115  may be coupled with the buttstock assembly  110  to allow the buttstock assembly  110  to expand and contract like a telescope in relation to the receiver extension  115 . The receiver extension  115  may have an upper tube portion  125  that is opposite an alignment rail  200  on the outer surface  205  ( FIG. 2 ). The buttstock assembly may be removably secured at one or more telescoping positions in relation to an aft end  120  of the firearm  100 . 
       FIG. 2  depicts the receiver extension  115 . The receiver extension  115  may have a length L that may vary depending on the configuration of the collapsible buttstock  105 . The receiver extension  115  may include the alignment rail  200  that extends longitudinally along the length L of the receiver extension  115 . The alignment rail  200  projects radially outwardly from an outer surface  205  and has a somewhat rectangular shaped cross section. An elongated slot  210  is formed into the alignment rail  200  and may include a plurality of cavities  215  provided within the elongated slot  210 . The plurality of cavities  215  are shown extending inwardly into the alignment rail  200  and may be disposed in a longitudinally-spaced relation to one another along a length C of the elongated slot  210 . The plurality of cavities may be spaced apart at regular intervals and may correspond to one or more telescoping positions. The alignment rail  200  may include one or more rail surfaces  220 . In the embodiment shown, the one or more rail surfaces  220  may include a first rail surface  220   a  and a second rail surface  220   b . In another embodiment, the one or more rail surfaces  220  may include the first rail surface  220   a  and the second rail surface  220   b  in addition to one or more intermediate rail surfaces that may be situated between the plurality of cavities  215 . The intermediate rail surfaces may be of the same height as the first rail surface  220   a  and the second rail surface  220   b  and may couple the first rail surface  220   a  to the second rail surface  220   b  between the plurality of cavities  215 . 
     As stated above, the receiver extension  115  may be configured for any length L. With the variation in the length L, the number of the plurality of cavities  215  may also be varied based on the application of the collapsible buttstock  105  ( FIG. 1 ). The number of telescoping positions as discussed above depends on the number of the plurality of cavities. In one example, the plurality of cavities  215  may be as few as two cavities. In another example, the plurality of cavities  215  may be as numerous as twenty cavities. In another embodiment, the plurality of cavities  215  may be as few as four cavities and as numerous as nine cavities. For a given length L, the plurality of cavities  215  may depend on a size and shape of a locking pin  405 , which is best shown in  FIG. 4A . The length L of the receiver extension  115  may be a standard length; however the locking pin  405  may be smaller than the standard size and shape. This may allow for more plurality of cavities  215  along the length L and allow for more telescoping positions. 
     The receiver extension  115  may be used to house a recoil assembly (not shown) to allow for operation of the firearm  100 . The recoil assembly may include an action spring (not shown) and a buffer assembly (not shown). The receiver extension  115  may be coupled to a firearm body  225  by welding, adhesives, twist lock, or a nut and bolt. In one embodiment, the receiver extension  115  may include a threaded body at one end of the outer surface  205  and the firearm body  225  may include a nut assembly. The threaded body of the receiver extension  115  may threadably couple with the nut assembly of the firearm body  225  and restrict the receiver extension  115  from rotating in relation to the firearm body  225 . In another embodiment, the receiver extension  115  may also be a buttstock mount (not shown) that does not serve to house the recoil assembly. The buttstock mount may be coupled to the firearm body  225  and may allow the buttstock assembly  110  to be slideably couple with the firearm  100 . The buttstock mount may mimic the features of the receiver extension  115  as shown in  FIG. 2 . 
       FIG. 3  depicts the components of the anti-rattle assembly  300 . A baseplate  305  may include a plurality of lower guides  310 , and a plurality of fasteners  320 . The plurality of lower guides  310  may be a vertical structure designed to capture and retain a bottom biasing portion  330 , respectively, of a respective biasing member  325 . The plurality of fasteners  320  may be used to secure the baseplate  305  to a buttstock body  400  as shown in  FIG. 5 . Each of the biasing members  325  may be a spring, a compressible foam, a compressible gel, and a compressible fluid. In some embodiments, the baseplate  305  may include a plate aperture  315  to allow the locking pin  405  (best shown by  FIG. 4A ) to pass through the baseplate  305  unimpeded. In this embodiment, the baseplate  305  may serve as a lower pin biasing guide for a pin biasing spring  410 . This would allow the pin biasing spring  410  to provide a biasing force on the locking pin  405  in an upward direction until the locking spring is acted on by a lever  450  as described below. 
     A pressure plate  340  may be situated vertically above the baseplate  305  as depicted by  FIG. 3  along vertical axis V. The pressure plate  340  may include one or more ridges  345   a  and  345   b , and a plurality of upper guides ( FIG. 5A ). The one or more ridges  345   a  and  345   b  are configured to contact under a biasing force from the biasing members  325 , the one or more rail surfaces  220   a  and  220   b , respectively, of the receiver extension  115  of  FIG. 2 . The plurality of upper guides may be vertically aligned with the plurality of lower guides  310 , and may be operable to capture and retain an upper biasing portion  355  of the biasing members  325 . The lower guides  310  and the upper guides may be operable to ensure that the biasing members  325  remain in an upright and/or vertical position. Each of the biasing members  325  provides a biasing force between the baseplate  305  and the pressure plate  340 . As explained below, the baseplate  305  may be coupled to the buttstock body  400  in one embodiment. The biasing force applies pressure along the vertical axis V to the pressure plate  340  and in turn, applies pressure to the one or more rail surfaces  220   a ,  220   b  through the one or more ridges  345   a ,  345   b . The biasing force, or pressure, applied to the receiver extension  115  creates a contact surface between the upper tube portion  125  of the receiver extension  115  and an upper body portion  415  of a tubular aperture  420  (best shown by  FIG. 4B ). The contact surface may be of any length to reduce or eliminate movement between the upper tube portion  125  and the receiver extension  115 . The biasing force is operable to reduce the movement of the buttstock body  400  in relation to the receiver extension  115 . The contact surface allows for the alignment of the upper tube portion  125  of the receiver extension  115  with an upper tube portion  125  of the tubular aperture with the applied pressure to reduce the movement of the buttstock body in relation to the receiver extension  115  and to maintain the alignment a tubular axis of the buttstock body  400  with a firearm axis F of the firearm  100  of  FIG. 1 . By maintaining the alignment of the buttstock body  400  with the firearm  100 , a user is able to maintain a sight picture and a cheek weld with the collapsible buttstock  105  with the need to readjust because of a shift of the buttstock body  400  in relation to the firearm  100 . 
     If the alignment rail  200  has the intermediate rail surfaces as described above, the one or more ridges  345   a ,  345   b  of the pressure plate  340  may include an intermediate ridge to contact and apply a biasing force or pressure to the receiver extension  115 . The intermediate ridge may span the distance between the one or more ridges  345   a ,  345   b  to contact the intermediate rail surfaces or the intermediate ridge may be a solid surface running the length of the one or more ridges. If the intermediate ridge is solid, a second plate aperture may be present and aligns with the plate aperture  315  of the base plate to allow the locking pin  405  to slideably couple with the pressure plate  340 . 
     A plurality of fastener apertures  360  may be included in the pressure plate  340  to allow for the movement of the pressure plate  340  along the vertical axis V without interference from the plurality of fasteners  320  being coupled to the buttstock body  400 . Referring to  FIG. 4A , when the baseplate  305  is coupled to the buttstock body  400  (i.e. the plurality of fasteners  320  coupled to a plurality of fastener positions  460  (same on opposite, non-depicted side of buttstock body  400 ), respectively, the plurality of fasteners  320  may restrict the movement of the pressure plate  340  along the vertical axis V. The plurality of fastener apertures  360  may allow for the movement of the pressure plate  340  without interference from the plurality of fasteners  320 . 
     The pressure plate  340  may also include one or more lower stops  370 . The buttstock body  400  may include one or more upper stops  500  of  FIG. 5A . When the one or more lower stops  370  and the one or more upper stops  500  are making contact, the pressure plate  340  is at an uppermost position along the vertical axis V. For example, when the receiver extension  115  is slideably coupled with the tubular aperture  420 , the one or more rail surfaces  220  of the alignment rail  200  exert a downward force in the direction of the vertical axis V on the pressure plate  340 . While the receiver extension  115  is slideably coupled with the tubular aperture  420  of the buttstock body  400 , the one or more upper stops  500  are not in contact with the one or more lower stops  370  i.e., a gap  590  exist between the lower and upper stops  370 ,  500  as depicted by  FIG. 5C . When the receiver extension  115  is removed from the tubular aperture  420  of the buttstock body  400 , the one or more upper stops  500  are in contact with the one or more lower stops  370  due to the biasing force apply by biasing members  325  ( FIG. 5A ) to move the one or more lower stops  370  into contact with the one or more upper sops  500 . 
       FIGS. 4A ,  4 B,  5 A,  5 B and  5 C depict the anti-rattle assembly  300  in relation to the buttstock body  400 . As depicted by  FIG. 4A , the buttstock body  400  may include a body axis B that runs longitudinally from a first end  435  to a second end  440  of the buttstock body  400 . The tubular aperture  420  may include a tubular axis T that may be parallel to the body axis B and a groove  425 , which the groove  425  is depicted in  FIG. 4B . The groove  425  is operable to receive the alignment rail  200  of the receiver extension  115 . The groove  425  may be along an outer tube wall  445  of the tubular aperture  420 . The groove  425  may be at the opposite from the upper body portion  415  along the outer tube wall  445 . 
     The locking pin  405  may be operable to removably secure the receiver extension  115  in relation to the buttstock body  400 . The locking pin  405  may include a pin axis P that is orthogonal to the tubular axis T as depicted in  FIG. 4A . The pin biasing spring  410  may provide a biasing force in an upward direction towards the groove  425  so that the locking pin  405  removable couples with the plurality of cavities  215  of the receiver extension  115 . When the locking pin  405  is in an extended position, the locking pin  405  may be removably coupled with a cavity of the plurality of cavities  215 . The coupling of the locking pin  405  and a cavity of the plurality of cavities  215  may restrict the movement of the receiver extension  115 , as depicted in  FIGS. 5A ,  5 B and  5 C. 
     A lever  450  may be hingedly coupled to the locking pin  405  and may provide a lever force to retract the locking pin  405  from the cavity of the one or more cavities  215 . A retracted position is defined when the lever  450  retracts the locking pin  405  from the cavity of the plurality of cavities  215 . The retracted position allows the collapsible buttstock  105  to either be moved to another telescoping position or to allow the receiver extension  115  to be removed from the tubular aperture  420  of the collapsible buttstock  105 . The pin biasing spring  410  biasing force may provide enough tension between the locking pin  405  and the lever  450  to ensure that the lever  450  does not move or slide when in a resting position. The pin biasing spring  410  also provides enough biasing force for the locking pin  405  to maintain the extended position. The resting position of the lever  450  may be when the locking pin  405  is in the extended position as it does not require any actuation to maintain the extended position. When the lever  450  is actuated in a first direction D (i.e. when a force is placed on the lever  450  in the first direction D as depicted by  FIG. 4A ), the locking pin  405  is placed in the retracted position. The retracted position allows the receiver extension  115  to be moved between cavities, i.e. telescoping position. However, the locking pin  405  is not retracted enough to remove it from the elongated slot  210  of  FIG. 2 . Therefore, the receiver extension  115  may still be captured by the buttstock body  400 . Alternatively, when the lever  450  is actuated in a second direction E as shown in  FIG. 4A , the locking pin is placed in a release position. The release position enables the receiver extension  115  to be removed from the tubular aperture  420 . 
     In another embodiment, a retaining ring  455  may be coupled to the locking pin  405  to capture and secure the lever  450 . In the illustrated embodiment, the lever  450  may be slideably coupled to the locking pin  405 . The retaining ring  455  may be threaded onto the locking pin  405  to secure and couple the retaining ring  455  to the locking pin  405 . In other embodiments, any suitable means for coupling the lever  450  to locking pin  405 , such as gluing, welding, etc., may be used. 
     The plurality of fastener positions  460  ( FIG. 4A ) may be located around a perimeter wall  465  of a rattle aperture  470 . The anti-rattle assembly  300  may be placed within the rattle aperture  470  of the buttstock body  400 . The plurality of fasteners  320  of the baseplate  305  removably secure with the plurality of fastener positions  460  to secure the anti-rattle assembly  300  within the buttstock body  400 . The one or more ridges  345  may protrude from the rattle aperture  470  into the groove  425  of the tubular aperture  420 . This may allow for the pressure plate  340  to apply the biasing force from biasing members  325  to the receiver extension  115 , via the one or more ridges  345   a ,  345   b  contacting the one or more rail surfaces  220   a  and  220   b , respectively, of the receiver extension  115  ( FIG. 2 ), to stop and/or restrict the movement of the receiver extension  115  within the tubular aperture  420 . 
       FIGS. 5A ,  5 B and  5 C depict the anti-rattle assembly  300  within the rattle aperture  470 . As described above, in one embodiment, the plurality of fasteners  320  are coupled with the plurality of fastener positions  460  to secure the baseplate  305  to the buttstock body  400 . The plurality of fasteners  320  may include at least one of the following, a barb fastener, a clip fastener, a rivet, a screw, a bolt and nut, an expansion bolt, a cantilever hook, a spring toggle, a turnbuckle, a pine in hole, a wedge in slot, a trap, a snap, a ball and socket, a cantilever spring, a crush rib, welding, brazing, solvent bonding, Velcro, a crimp, and a seam. The plurality of fastener apertures  360  include at one of the following fastener aperture operable to receive the fastener and a solid blank. The biasing members  325  may be captured and secured between the baseplate  305  and the pressure plate  340 . The locking pin  405  is shown protruding into the a cavity of the plurality of cavities  215  while the locking pin  405  is in the extended position (e.g. resting position). The receiver extension  115  of  FIG. 2  is shown inserted into the tubular aperture  420 . 
     When the receiver extension  115  is inserted into the tubular aperture  420 , the pressure plate  340  may be directed downward along the vertical axis V ( FIG. 3 ) and partially or completely compress the biasing members  325 . A ramp  520  as shown in  FIGS. 4A and 5B , may be operable to move the pressure plate  340  in the downward direction as the receiver extension  115  is inserted into the tubular aperture  420 . In other words, as the receiver extension  115  engages the ramp  520  of the pressure plate  340 , the pressure plate  340  is directed down along vertical axis V of  FIG. 3 . A stop gap  510  may be created when the receiver extension  115  is inserted into the tubular aperture  420 . The stop gap  510  is the space between the one or more upper stops  500  and the one or more lower stops  370  when the receiver extension  115  is inserted into the tubular aperture  420 . Alternatively, with the receiver extension  115  removed from the tubular aperture  420 , the one or more ridges  345  may fully protrude into the groove  425 . The one or more upper stops  500  are in contact with the one or more lower stops  370  when the receiver extension  115  is removed from the tubular aperture  420  of the buttstock body  400 . The contact between the one or more upper stops  500  and the one or more lower stops  370  may also serve to restrict the amount of pressure the biasing member  325  may exert on the receiver extension  115  when the receiver extension  115  is slideably coupled with the tubular aperture  420 . 
     In another embodiment, the lever  450  may include features of the baseplate  305  to include the plurality of lower guides  310  and the plurality of fasteners to removably secure the anti-rattle assembly to the plurality of fastener positions within the rattle aperture of the buttstock body  400 . In other words, the baseplate  305  is integral with the lever  450 . The plate aperture  315  of the baseplate  305  may be disposed on the lever  450 . The second plate aperture (not shown) of the pressure plate  340  may align with the plate aperture  315  of the lever  450  to define a through bore. It is to be appreciated that placing the locking pin  405  in the retracted position and/or the release position, lessens the biasing force applied by biasing members  325 . In the retracted position, the lever  450  moved away from the buttstock body  400  and hence the pressure applied by the pressure plate  340  to the one or more rail surfaces  220   a ,  220   b  through the one or more ridges  345   a ,  345   b , may be reduced as the biasing members  325  extend and/or relax. In other words, this lessening of the biasing force, and hence contact pressure, results from applying a force to the lever  450  in the first direction D, which creates spacing that likewise permits plurality of lower guides  310  to move away relatively from the pressure plate  340  via expansion of the biasing members  325   a ,  325   b , basically simultaneously, when the locking pin  405  is place in the retracted position. This reduction of the pressure applied by the pressure plate  340  to the one or more rail surfaces  220   a ,  220   b , is such that the pressure plate  340  will not hinder the movement of the collapsible buttstock  105  along the receiver extension  115 . Likewise, when the locking pin  405  is in the extended position, i.e., normal resting position, the lever  450  closes the spacing between the plurality of lower guides  310  and the pressure plate  340 , via pin biasing spring  410  providing a biasing force on the locking pin  405  in the upward direction and which results in the locking pin  405  and the pressure plate  340  engaging in at least two different places and at least under two different biasing forces, via biasing members  410 ,  325 , the receiver extension  115  as is depicted by  FIG. 5A . 
     It is noted that the terms “substantially” and “about” may be utilized herein to represent the inherent degree of uncertainty that may be attributed to any quantitative comparison, value, measurement, or other representation. These terms are also utilized herein to represent the degree by which a quantitative representation may vary from a stated reference without resulting in a change in the basic function of the subject matter at issue. 
     Certain terminology is used in the disclosure for convenience only and is not limiting. The words “left”, “right”, “front”, “back”, “top”, “bottom”, “upper”, and “lower”, “vertical”, and “horizontal” designate directions in the drawings to which reference is made. The terminology includes the words noted above as well as derivatives thereof and words of similar import. 
     While particular embodiments have been illustrated and described herein, it should be understood that various other changes and modifications may be made without departing from the spirit and scope of the claimed subject matter. Moreover, although various aspects of the claimed subject matter have been described herein, such aspects need not be utilized in combination. It is therefore intended that the appended claims cover all such changes and modifications that are within the scope of the claimed subject matter.