Abstract:
Slide retraction levers for use with firearms are described. In one example implementation, the slide retraction lever for use with a firearm includes a first handle and a second handle. The first and second handles are used to retract the slide retraction lever. Additionally, the first and second handles are positioned on opposite sides of the slide retraction lever. The slide retraction lever further includes a locking device that is associated with the first handle. Operating the first handle releases an engagement with the firearm. Additionally, the locking device is associated with the second handle. Operating the second handle releases the engagement with the firearm independent of the operation of the first handle.

Description:
RELATED APPLICATION 
       [0001]    This patent is a continuation of International Patent Application Serial No. PCT/EP2007/001005, filed Feb. 6, 2007, which claims priority to German Patent Application 10 2006 006 034.2, filed on Feb. 9, 2006, both of which are hereby incorporated herein by reference in their entireties. 
     
    
     FIELD OF THE DISCLOSURE 
       [0002]    This patent relates generally to firearms and, more specifically, to slide retraction levers for use with firearms. 
       BACKGROUND 
       [0003]    Some semi-automatic hand held firearms, including lower-cost semi-automatic rifles for small-caliber cartridges, are provided with a slide retraction lever or locking device that is coupled to the breech and extends through the weapon housing. The slide-retraction lever can advantageously be used to press the breech shut if it does not fully and/or properly close. However, because the slide retraction lever is coupled to the breech, it extends through the weapon housing and must be allowed to move parallel to the firearm. Specifically, as the breech opens and closes during firing, the slide retraction lever moves along with the breech on the outside of the firearm. If the slide retraction lever collides with an obstacle, there is a tendency for the firearm to jam. Additionally, injury may occur if the slide retraction lever collides with a body part of the marksman or a person in close proximity to the marksman. 
         [0004]    Prior to the First World War, reloading devices were manufactured that were provided with a slide retraction lever that decoupled from the breech after the breech was initially retracted to chamber a round (e.g., a bullet). By decoupling the slide retraction lever from the breech, the slide retraction lever no longer had the tendency to collide with obstacles. However, the slide retraction lever could not advantageously be used to close the breech if it did not fully and/or properly close. Today, slide retraction levers typically decouple from the breech. 
         [0005]    Known slide retraction levers are attached to either the right side or the left side of the firearm. For example, DE 101 22 345 C1, which is assigned to the assignee of the present patent, describes a cocking lever that is attached to one side of the firearm. The cocking lever may move the breech against the force of a spring into various positions. The weapon housing is provided with a longitudinal slot with a rigid clamping rail in which the cocking lever can be inserted and clamped. 
         [0006]    Additionally, for example DE 39 28 125 A1, which is assigned to the assignee of the present patent, describes a slide retraction lever that is rotatable between the right side and the left side of the firearm. The slide retraction lever is inserted in a slot that longitudinally extends in the weapon housing outside of the firearm. 
         [0007]    Further, DE 19545774 C2, which is assigned to the assignee of the present patent, describes a self-loading rifle that includes a cocking lever with a hand grip that protrudes from the weapon housing. The cocking lever can only be operated on one side of the firearm. The cocking lever is biased by a spring and includes a nose that can engage a construction within the weapon housing. To disengage the nose from the construction, the hand grip can be rotated while sliding the cocking lever back. 
         [0008]    The American M16A2 includes a slide retraction lever that has a T-shaped hand grip that can be operated from both sides of the firearm. However, an arm that is removably coupled to the weapon housing between an unlocked and a locked position is only on one side of the hand grip. Specifically, the arm includes a protrusion that engages a recess defined by the weapon housing to substantially prevent movement of the slide retraction lever relative to the weapon housing. To release the slide retraction lever, the protrusion is removed from the recess by rotating the arm. 
         [0009]    During operation and/or firing of military rifles, conditions such as pollution and temperature vary, which impact the likelihood of a cartridge getting jammed in a cartridge chamber. If a cartridge gets jammed, the breech can no longer properly close and the rifle may become inoperable. Additionally, significant danger may be posed to the operator if the breech is unable to close. 
         [0010]    Known reloading devices can operate only from the right side or the left side of the firearm. Specifically, in known firearms, the slide retraction lever locks (e.g., engages the recess) on only one side of the firearm. Therefore, known slide retraction levers are designed for a right handed marksman or a left handed marksman, but not a right handed marksman and a left handed marksman. Having different firearms for right handed marksmen and left handed marksmen impacts costs related to storage, distribution, logistics and administration. Additionally, firearms manufactured for left-handed marksman increase production and acquisition costs because production runs are relatively low. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS  
         [0011]      FIG. 1  illustrates a partially sectional view of a portion of an example firearm including an example slide retraction lever. 
           [0012]      FIG. 2  illustrates a cross-sectional view of the example firearm and the example slide retraction lever of  FIG. 1  in a locked position. 
           [0013]      FIG. 3  illustrates a cross-sectional view of the example firearm and the example slide retraction lever of  FIG. 1  in an unlocked position. 
           [0014]      FIG. 4   a  illustrates a top view of the example slide retraction lever of  FIG. 1 . 
           [0015]      FIG. 4   b  illustrates a top cross-sectional view of the example slide retraction lever of  FIG. 1 . 
           [0016]      FIG. 5  illustrates a side view of the example slide retraction lever of  FIG. 1 . 
           [0017]      FIG. 6   a  illustrates a perspective view of the example slide retraction lever of  FIG. 1  and an example guide. 
           [0018]      FIG. 6   b  illustrates a bottom view of the example slide retraction lever and the example guide of  FIG. 6   a.    
       
    
    
     DETAILED DESCRIPTION  
       [0019]    Certain examples are shown in the above-identified figures and described in detail below. In describing these examples, like or identical reference numbers are used to identify common or similar elements. The figures are not necessarily to scale and certain features and certain views of the figures may be shown exaggerated in scale or in schematic for clarity. Additionally, several examples have been described throughout this specification. Any features from any example may be included with, a replacement for, or otherwise combined with other features from other examples. Further, throughout this description, position designations such as “above,” “below,” “top,” “forward,” “rear,” “left,” “right,” etc. are referenced to a firearm held in a normal firing position (i.e., wherein the “shooting direction” is pointed away from the marksman in a generally horizontal direction) and from the point of view of the marksman. Furthermore, the normal firing position of the weapon is always assumed, i.e., the position in which the barrel runs along a horizontal axis. 
         [0020]    The example methods and apparatus described herein can be used advantageously to retract a slide-retraction lever on either the right hand side or the left hand side of a firearm. In particular, the example methods and apparatus described herein can be interchangeable used by both right handed marksmen and left handed marksmen to retract the slide retraction lever to move the breech system and/or to remove jammed cartridges from a cartridge chamber. The example methods and apparatus described herein reduce costs associated with storing and distributing the firearms because the same firearms may be used by both right handed marksmen and left handed marksmen. Further, the example methods and apparatus described herein reduce costs associated with manufacturing because different parts are no longer needed to manufacture weapons for right handed marksmen and weapons for left handed marksmen. 
         [0021]    The example methods and apparatus described herein relate to a firearm that is provided with a slide retraction lever that includes a first handle and a second handle to move the slide retraction lever. The first handle and the second handle are arranged on opposite sides of the weapon. The first handle and the second handle each include a clip that is moveable between a locked position and an unlocked position to release the slide retraction lever upon operating either the first handle or the second handle. 
         [0022]      FIG. 1  is an illustrated example of a firearm  100  including a weapon housing  2 , a barrel  4 , a breach system  6 , a stock  8 , a trigger  10 , and a handle  12 . For clarity, some components are not depicted and/or described herein such as, for example, a trigger mechanism. 
         [0023]    A cartridge chamber  102  is positioned towards the rear of the barrel  4  and is adjacent the breech system  6 . The breech system  6  can move within the weapon housing  2  to lock and/or move a cartridge (not shown) into the cartridge chamber  102  (e.g., the position in which the cartridge may be fired through the barrel  4 ). The breech system  6  includes a breach head  16  and a breach block support  18 . A surface  104  of the breech head  16  defines a recess  106  that substantially corresponds to a size and/or a shape of the cartridge. An extractor (not shown) is positioned adjacent the recess  106  and engages an edge (e.g., a base edge) of the cartridge. Additionally, the extractor assists in ejecting a casing (not shown) of the cartridge from the cartridge chamber  102  after the cartridge is fired. 
         [0024]    Towards the rear of the weapon housing  2 , a slide retraction lever  22  is positioned above and substantially coaxial with the barrel  4 . The slide retraction lever  22  is provided with a hand grip  24  (e.g., a T-shaped hand grip  24 ) that extends out of the weapon housing  2  and towards the rear of the firearm  100 . 
         [0025]    Turning to  FIG. 2 , the hand grip  24  includes a first handle  26  and a second handle  28  that are positioned on opposite sides of the firearm  100 . The first handle  26  and the second handle  28  include a first gripping surface  202  and a second gripping surface  204 , respectfully. Additionally, the first and second handles  26  and  28  are associated with unlocking the slide retraction lever  22 . To unlock the slide retraction lever  22 , a force is applied to either the first gripping surface  202  and/or the second gripping surface  204  in a direction generally indicted by arrows  206  and  208 . In this example implementation, the first and second gripping surfaces  202  and  204  include ribs or ridges  212  or any other suitable surface structure that may assist the marksman in gripping the first and/or second handles  26  and  28 . Additionally, the first handle  26  and the second handle  28  define a first aperture  214  and a second aperture  216 , respectfully, that reduce the overall weight of the hand grip  24 . 
         [0026]    The hand grip  24  may be manufactured or otherwise fabricated (e.g., milled) from a single piece of material. The first handle  26  includes a protrusion  32  that substantially corresponds to a recess  34  defined by the second handle  28 . The first handle  26  defines a first bore  218  and the second handle  28  defines a second bore  220 . The first bore  218  and the second bore  220  each receive fasteners  222 ,  223  and, the first and second handles  26  and  28  respectfully pivot around the fasteners  222 ,  223 . Additionally, the first handle  26  defines a first spring seat  224  and the second handle  28  defines a second spring seat  226 . A spring  30  is positioned within a transversal bore  228  defined by the hand grip  24  between the first and second spring seats  224  and  226 . The spring  30  exerts a force and/or pre-stresses the first and second handles  26  and  28 .  FIG. 2  depicts the first and second handles  26  and  28  in a substantially rest position. 
         [0027]    A coupling mechanism between the first handle  26  and the second handle  28  includes the protrusion  32  and the recess  34 . As discussed above, the protrusion  32  corresponds to the recess  34 . Specifically, the protrusion  32  and the recess  34  are positioned adjacent each other to couple the rotational movement of the first handle  26  and/or the second handle  28  together. More specifically, the protrusion  23  includes a rounded portion  230  that engages a substantially rectangular profile  231  of the recess  34 . If the first handle  26  is rotated around the fastener  222  in a direction generally indicated by arrow  208 , the protrusion  32  rotates along with the first handle  26 . As the protrusion  32  rotates, the rounded portion  230  of the protrusion  32  engages and exerts a force within the recess  34 , which, in turn, rotates the second handle  28  around the fastener  223  in a direction generally indicated by arrow  206 . Alternatively, if the second handle  28  is rotated around the fastener  223  in a direction generally indicated by arrow  206 , the recess  34  rotates along with the second handle  28 . As the recess  34  rotates, the rectangular profile  231  of the recess  34  engages and exerts a force against the protrusion  32 , which, in turn, rotates the first handle  26  around the fastener  222  in a direction generally indicated by arrow  208 . The force applied to rotate either the first and/or second handles  26  and  28  substantially overcomes the force exerted by the spring  30 . 
         [0028]    The first handle  26  is provided with a first arm  232  including a first clip  234  that corresponds to a first recess  236 . The spring  30  exerts a force on the first handle  26  to urge the first clip  234  to engage the first recess  236  and to substantially lock the slide retraction lever  22  relative to the weapon housing  2  as shown in  FIG. 2 . However, if a force is applied to the first handle  26  as described above, the first clip  234  disengages the first recess  236  as shown in  FIG. 3 . Additionally, the second handle  28  is provided with a second arm  238  including a second clip  240  that corresponds to a second recess  242 . The spring  30  exerts a force on the second handle  28  to urge the second clip  240  to engage the second recess  242  and to substantially lock the slide retraction lever  22  relative to the weapon housing  2  as shown in  FIG. 2 . However, if a force is applied to the second handle  28  as described above, the second clip  240  will disengage the second recess  242  as shown in  FIG. 3 . 
         [0029]    Additionally, the coupling mechanism may unlock and/or release the slide retraction lever  22 . For example, to release the slide retraction lever  22 , the marksman may apply a force to the first handle  26  and the first clip  234  may disengage the first recess  236 , which, in turn, causes the second clip  240  to disengage the second recess  242 . Alternatively, to release the slide retraction lever  22 , the marksman may apply a force to the second handle  28  and the second clip  240  may disengage the second recess  242 , which, in turn, causes the first clip  234  to disengage the first recess  236 . The force applied to either the first and/or second handles  26  and  28  (e.g., toward the rear of the firearm  100 ) to disengage the first and/or second clips  234  and  240  is substantially opposite the force applied by the spring  30 . 
         [0030]    In the rest position (e.g., the position in which the first and second clips  234  and  240  engage the first and second recesses  236  and  242 ), the hand grip  24  of the slide retraction lever  22  is adjacent to and/or rests on a surface  108  ( FIG. 1 ) of the weapon housing  2 . Turning to  FIG. 3 , if the first and second clips  234  and  240  disengage the first and second recesses  236  and  242 , an elongated portion  302  of the slide retraction lever  22  may move and/or slide within a guide  44  defined by the weapon housing  2  in a direction generally indicated by arrow  304  toward the rear of the firearm  100 . A size and/or shape of the elongated portion  302  substantially corresponds to a size and/or shape the guide  44 . Specifically, the elongated portion  302  includes one or more ribs  56  ( FIG. 6   a ) (e.g., horizontal ribs) that correspond to one or more grooves  602  ( FIG. 6   a ) (e.g., transversal groove) defined by the guide  44 . The interaction between the ribs  56  ( FIG. 6   a ) and the grooves  602  ( FIG. 6   a ) may maintain the coaxial position of the slide retraction lever  22  relative to the weapon housing  2 . In some examples, the elongated portion  302  may have two ribs  56  on opposite sides of the elongated portion  302  that correspond to two grooves  602  ( FIG. 6   a ) defined by the guide  44 . 
         [0031]    Turning back to  FIG. 1 , the slide retraction lever  22  includes a nose  60  on an end of the slide retraction lever  22 . The nose  60  is adjacent to and may engage a surface  110  of a step  62  of the breech system  6 . If the slide retraction lever  22  is disengaged and moved toward the rear of the firearm  100 , the nose  60  engages the step  62  and moves and/or retracts the breech system  6  to, for example, initiate chambering a round (e.g., a cartridge). The firearm  100  includes a gas extraction rod (not shown) that interacts with the breech system  6 . Specifically, after a round is fired, the gas extraction rod moves the breech system  6  toward the rear of the firearm  100  to initiate reloading. 
         [0032]    Turning to  FIG. 6   a , the guide  44  defines an aperture  58  that may be substantially semi-circular. The aperture  58  enables a control bolt (not shown) to move at least partially within the aperture  58  when the breech system  6  is being guided into a locked position. To remove the slide retraction lever  22  from the guide  44 , the breech system  6  ( FIG. 1 ) is pulled and/or moved toward the rear of the firearm  100  ( FIG. 1 ) and rotated downwards, which then provides access to the slide retraction lever  22 . The slide retraction lever  22  is then moved and/or pulled toward the rear of the firearm  100  until the ribs  56  are substantially adjacent a clearance  54 . Once the ribs  56  are adjacent the clearance  54 , the ribs  56  may disengage the grooves  602  and, the slide retraction lever  22  may be removed from the firearm  100  (e.g., removed downwardly from the firearm  100 ). The slide retraction lever  22  may be removed for any suitable purpose such as, for example, cleaning and/or replacement. 
         [0033]    Turning now to  FIGS. 4   a  and  4   b , the slide retraction lever  22  defines a slot  50  (e.g., a longitudinal slot) along the elongated portion  302  between the nose  60  and the hand grip  24 . The slot  50  enables the breech block support  18  ( FIG. 1 ) along with a gas rod (not shown) to move back and forth freely within the slot  50 . As the slide retraction lever  22  is moved toward the rear of the firearm  100 , the nose  60  engages and moves the breech block support  18  ( FIG. 1 ) into the clamped and/or locked position against a force of a recoil spring (not shown). Once the breech system  6  ( FIG. 1 ) and the breech block support  18  ( FIG. 1 ) are retracted and in the clamped and/or locked position, the slide retraction lever  22  may then be moved back to the position in which the first and second clips  234  and  240  ( FIG. 2 ) engage the first and second recesses  236  and  242  ( FIG. 2 ) (e.g., the locked position). However, the breech system  6  ( FIG. 1 ) and the breech block support  18  ( FIG. 1 ) may remain in the clamped and/or locked position. 
         [0034]    If the firearm  100  is a closed bolt position firearm, retracting the slide retraction lever  22  may retract the breech system  6  to guide a cartridge into the cartridge chamber  102  and then the breech system  6  may close and/or lock. Alternatively, if the firearm  100  is an open bolt position firearm, retracting the slide retraction lever  22  may retract the breech system  6  until the breech system  6  is engaged by the trigger mechanism behind a cartridge feed (not shown). 
         [0035]    If a cartridge becomes jammed within the firearm  100 , for example, within the cartridge chamber  102  and/or the breech system  6 , the slide retraction lever  22  may be unlocked and pulled and/or moved toward the rear of the firearm  100 , as described above. Moving the slide retraction lever  22  may engage the nose  60  with at least a portion of the breech system  6  to dislodge and/or eject the jammed cartridge and enable the firearm  100  to again be loaded and fired. 
         [0036]      FIG. 2  illustrates a top view of the first and second handles  26  and  28  of the slide retraction lever  22  in the locked position. Specifically,  FIG. 2  depicts the first and second clips  234  and  240  engaging the first and second recesses  236  and  242  and, the spring  30  in a substantially relaxed position. 
         [0037]      FIG. 3  illustrates the first and second handles  26  and  28  in an unlocked position and the elongated portion  302  partially removed from the guide  44 . 
         [0038]      FIG. 4   a  illustrates a top of the slide retraction lever  22 , and  FIG. 4   b  illustrates a top cross-sectional view of the slide retraction lever  22 . 
         [0039]    As discussed above, the firearm  100  includes the slide retraction lever  22  that has the first handle  26  and the second handle  28  that are on opposite sides of the firearm  100  and may be utilized to retract the slide retraction lever  22 . The first handle  26  includes the first arm  232  with the first clip  234  that corresponds to the first recess  236 . In addition, the second handle  28  includes the second arm  238  with the second clip  240  that corresponds to the second recess  242 . By moving the first or second handles  26  and  28 , the first and second clips  234  and  240  disengage their respective recesses  236  and  242 . Specifically, the first handle  26  may independently disengage the first recess  236  even if the marksman does not move the second handle  28 . Additionally, the second handle  28  may independently disengage the second recess  242  even if the marksman does not move the first handle  26 . 
         [0040]    As discussed above, the first and second clips  234  and  240  may be disengaged from the first and second recesses  236  and  242  from either the right side or the left side of the firearm  100  by moving either the first or second handles  26  and  28 . Firearms that may be universally used by both right handed marksmen and left handed marksmen decrease the amount of time and cost associated with procuring, managing and distributing the firearms, specifically, for example, during military actions or in the military field. 
         [0041]    The methods and apparatus described herein may be used with any suitable firearm or weapon such as, for example, any hand-held firearm that includes a slide retraction lever, such as, an automatic weapon, a semi-automatic weapon, a small-caliber weapon, a large-caliber weapon, a machine gun, a submachine gun, a pistol, etc. Additionally, the methods and apparatus described herein may be advantageously used to remove and/or eject a jammed cartridge within the firearm. Further, the methods and apparatus described herein may reduce some dangers posed to the marksman and those in close proximity to the marksman in addition to reducing operation failures associated with known firearms. For example, if the marksman is left handed, the marksman does not have to reach over to the right hand side of the firearm  100  to retract the slide retraction lever  22  as would be necessary if the left handed marksman was operating a known right handed firearm. Additionally, for example, if the marksman is right handed, the marksman does not have to reach over to the left hand side of the firearm  100  to retract the slide retraction lever  22  as would be necessary if the right handed marksman was operating a known left handed firearm. 
         [0042]    As discussed above, the first handle  26  includes the protrusion  32  that corresponds to the recess  34  defined by the second handle  28 . The first handle  26  is rotatably coupled to the slide retraction lever  22  via the fastener  222  and the second handle  28  is rotatably coupled to the slide retraction lever  22  via the fastener  223 . The interaction between the protrusion  32  and the recess  34  are associated with coupling the rotational movement of the first handle  26  to the second handle  28  and/or coupling the rotational movement of the second handle  28  to the first handle  26 . Specifically, the interaction between the protrusion  32  and the recess  34  may be similar to the interaction of the teeth on a gear wheel. However, in some example implementations, the protrusion  32  must be slightly offset relative to the recess  34  to achieve the desired leverage and to couple the rotational movement of the first and second handles  26  and  28 . 
         [0043]    As described above, the protrusion  32  includes the rounded portion  230  and the recess  34  has the rectangular profile  231 . However, the protrusion  32  and the recess  34  may have any other suitable geometry such as, for example, a spherical geometry, a conical geometry, a tear-drop shaped geometry, or a geometry that includes rounded edges, etc. Additionally, the protrusion  32  and/or the recess  34  may be undercut. 
         [0044]    As discussed above, the slide retraction lever  22  is provided with the spring  30  that pre-stresses the first and second handles  26  and  28  in the rest position. Specifically, the spring  30  engages and/or is coupled to the first handle  26  and the second handle  28 . The spring  30  may be any suitable spring such as for example, a leaf spring, a disk spring, a plurality of disc springs, a compression spring, etc. Additionally, the spring  30  may be made of any suitable material such as, for example, an elastomeric material or a metal material. 
         [0045]    As described above, the first and second handles  26  and  28  are coupled to the slide retraction lever  22  and are provided with the first gripping surface  202  and the second gripping surface  204 , respectfully. Additionally, the first and/or second clips  234  and  240  may disengage the first and/or second recesses  236  and  242  by pulling either the first or second handles  26  and  28  toward the rear of the firearm  100 . In other example implementations, the first and second handles  26  and  28  may be arranged in any other suitable position relative to the firearm  100  such as, for example, the first and second handles  26  and  28  may be arranged latterally or opposite the position as illustrated in  FIG. 2 . 
         [0046]    As discussed above, the first and second handles  26  and  28  are provided with the first and second arms  232  and  238 , respectfully. The first arm  232  includes the first clip  234  and the second arm  238  includes the second clip  240 . The first and second clips  234  and  240  engage the first and second recesses  236  and  242  that are defined by the weapon housing  2 . In other example implementations, the first and second recesses  236  and  242  may be defined by the barrel  4 . However, it may be less expensive to manufacture the firearm  100  if the weapon housing  2  defines the first and second recesses  236  and  242 . 
         [0047]    In other example implementatiions, the slide retraction lever  22  may be provided with the first and second handles  26  and  28 . However, the slide retraction lever  22  may only be provided with one arm such as, the first arm  232  or the second arm  238  that enages the respective recess  236  and  242 . Specifically, both the first and second handles  26  and  28  would be operatively coupled to the arm. 
         [0048]    As described above, the slide retraction lever  22  includes the elongated portion  302  that is movable within the guide  44  in the longitudinal direction relative to the firearm  100 . Additionally, an end of the elongated portion  302  is provided with the nose  60  that is to engage a portion of the breech system  6 . The first and second handles  26  and  28  are coupled to an opposite end  48  of the elongated portion  302  relative to the nose  60 . In other example implementations, the slide retraction lever  22  may be positioned in any other suitable location on the firearm  100  such as, for example, on the outside of the firearm  100 . 
         [0049]    The slide retraction lever  22  and the weapon housing  2  may be manufactured from any suitable material such as, for example, a metal material, a plastic material, a plastic material that is reinforced with a fiber glass material, or a thin sheet metal material. 
         [0050]    In some examples, the slide retraction lever  22  may directly engage the breech system  6 . However, in other exmples, such as if the breech system  6  includes the breech head  16  and the breech support block  18 , the slide retraction lever  22  may engage the breech support block  18 . 
         [0051]    The slide retraction lever  22  may directly or indirectly engage the breech system  6  such as, for example, the slide retraction lever  22  may be coupled to a connecting element (not shown) that is also coupled to the breech system  6 . However, as discussed above, the slide retraction lever  22  may engage the breech system  6  as the slide retraction lever  22  is moved toward the rear of the firearm  100 . 
         [0052]    Although certain example methods, apparatus and articles of manufacture have been described herein, the scope of coverage of this patent is not limited thereto. On the contrary, this patent covers all methods, apparatus and articles of manufacture fairly falling within the scope of the appended claims either literally or under the doctrine of equivalents.