Patent Publication Number: US-2023160654-A1

Title: Linear crossbow

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application is a continuation of U.S. patent application Ser. No. 16/840,446, filed on Apr. 5, 2020 and claims the benefit of U.S. Provisional Patent Application No. 62/829,913, filed on Apr. 5, 2019, the entire contents of which are incorporated herein by reference. 
    
    
     BACKGROUND 
     This application generally relates to crossbows and projectile launchers, and more particularly to linear crossbows with an arrow shuttle that operates in a linear manner parallel to arrow flight path, thus making for a safe shooting, extremely accurate, easily cocked, and compact crossbow. 
     Crossbows are generally known in the art. Crossbows typically include a bow portion, a stock portion, and a draw string latch that holds the bow in the fully drawn position. Typically, the draw string is perpendicular to the arrow or direction of flight. Furthermore, the draw string when shooting moves aggressively from the drawn position to the rest position. Accordingly, objects must remain free of the flight path of the draw string. 
     Today, most crossbow manufactures are designing crossbows to reduce the felt recoil, making them narrower, efficient, and as accurate and safe as possible. The most common method to reduce recoil is to make the limbs oriented such that the limbs are parallel to one another, thus cancelling most of the recoil. In doing so, the riser for the bow portion of the crossbow becomes wider and increases the length and weight of the crossbow while trying to maintain a power stroke. 
     Furthermore, manufacturers are attempting to minimize power cable wear that must be guided below and away from the draw string and arrow fletching. The power cables on most crossbows today are guided and under significant load and wear prematurely, thus reducing accuracy, efficiency, and safety. The narrower the crossbow is made the more difficult guiding the power cables become since the distance is reduced increasing the load and wear. Also, crossbows on the market all suffer from left to right movement or timing issues of the draw string reducing the accuracy if cocked incorrectly, or if the timing cables becomes out of time making the crossbow shoot left or right of the intended target. Numerous camming means have been developed to reduce the power cabling wear and make the crossbow narrow, but these suffer from drawbacks such as left to right movement of the drawstring. 
     Currently, most crossbows are very efficient and produce speeds in excess of 400 feet per second (f.p.s.); however, they all suffer from power cable wear and left to right draw movement. Also, the means for cocking crossbows on the market involve either hand cocking or using a rope cocker that pulls the draw string to the string latch, or another method is to move the string latch and pull the latch and draw string back to the cocked position. One problem with both of these methods is premature wear on the draw string by the string latch and rope cocker. 
     SUMMARY 
     One embodiment relates to a crossbow that includes a stock defining a front end and a rear end, and a limb including: a fixed end affixed to the stock between the front end and the rear end, and a free end positioned between the front end and the rear end. The limb is configured to flex in a substantially vertical plane. 
     Another embodiment relates to a crossbow that includes a stock defining a projectile flight path, a string let out assembly rotatably coupled to the stock about an axis of rotation perpendicular to the projectile flight path, the string let out assembly including a drawstring groove configured to support a drawstring, and a cable groove configured to support a power cable, and a limb including: a fixed end affixed to the stock below the projectile flight path, and a free end configured to couple to the power cable and flex in a substantially vertical plane. 
     Another embodiment relates to a crossbow that includes a stock defining a rear end, and a string let out assembly including: a drawstring groove configured to support a drawstring, a first cable groove configured to support a first power cable, and a second cable groove configured to support a second power cable. The drawstring groove, the first power cable groove, and the second power cable groove rotate about an axis of rotation. The crossbow also includes a first limb including: a first fixed end affixed to the stock between the rear end and the axis of rotation of the string let out assembly, and a first free end configured to couple to the first power cable and flex in a first substantially vertical plane, and a second limb including: a second fixed end affixed to the stock between the rear end and the axis of rotation of the string let out assembly, and a second free end configured to couple to the second power cable and flex in a second substantially vertical plane. 
     This summary is illustrative only and is not intended to be in any way limiting. Other aspects, inventive features, and advantages of the devices or processes described herein will become apparent in the detailed description set forth herein, taken in conjunction with the accompanying figures, wherein like reference numerals refer to like elements. 
    
    
     
       BRIEF DESCRIPTION OF THE FIGURES 
         FIG.  1    is a left side perspective view of a linear crossbow according to the principles of the present disclosure; in particular  FIG.  1    illustrates a very narrow arrangement of the linear crossbow in the drawn position. 
         FIG.  2    is a left perspective view of the linear crossbow of  FIG.  1   , the linear crossbow illustrated in an undrawn configuration. 
         FIG.  3    is left side cross section view of the linear crossbow of  FIG.  1   , the linear crossbow illustrated in a drawn configuration and a detailed string path view. 
         FIG.  4    is a left side cross section view of the linear crossbow of  FIG.  1    in the undrawn position along with a detailed string path view. 
         FIG.  5    is a left side perspective cross section view of the linear crossbow of  FIG.  1    in the undrawn position along with a lower detailed view showing the string paths more detailed. 
         FIG.  6    is a right side perspective exposed view without stock of the linear crossbow of  FIG.  1    showing the right side and the inner details in the undrawn position. 
         FIG.  7    is a right side perspective view with the right side of stock cross section removed to show the right side inner working and the linear crossbow of  FIG.  1    in the drawn position. 
         FIG.  8    is a front view looking back at the shooter view thru the linear crossbow of  FIG.  1    in the drawn position. 
         FIG.  9    is a back view of the linear crossbow of  FIG.  1    in the drawn position with the stock portion removed to better show the details. 
         FIG.  10    is a top view of the linear crossbow of  FIG.  1    in the drawn position. 
         FIG.  11    is a perspective view of another linear crossbow with forward string let out track and a limb arrangement with rearward facing limbs in the drawn position. 
         FIG.  12    is a right side view of the linear crossbow of  FIG.  11   . 
         FIG.  13    is a top view of the linear crossbow of  FIG.  11    in the draw position. 
         FIG.  14    is a perspective view of the linear crossbow of  FIG.  11    in the drawn position and internal components exposed. 
         FIG.  15    is a perspective view of another linear crossbow of  FIG.  11    in the drawn position with the components exposed showing the left side. 
         FIG.  16    is a perspective view of the linear crossbow of  FIG.  11    in the drawn position and internal components exposed showing the right side. 
         FIG.  17    is a top view of the linear crossbow of  FIG.  11    in the drawn position with components exposed. 
         FIG.  18    is a perspective view of the linear crossbow of  FIG.  11    in the undrawn position and a left side overview. 
         FIG.  19    is a perspective view of the linear crossbow of  FIG.  11    in the undrawn position and the right side view with components exposed. 
         FIG.  20    is a right side perspective view of the linear crossbow of  FIG.  11    in the undrawn further detailing the string paths and connection points. 
         FIG.  21    is a perspective of another linear crossbow with a forward let out string track with limbs facing in the forward direction in the drawn position. 
         FIG.  22    is a right side view of the linear crossbow of  FIG.  21   . 
         FIG.  23    is a top view of the linear crossbow of  FIG.  21    in the drawn position. 
         FIG.  24    is a left side perspective view of the linear crossbow of  FIG.  21    in the drawn position showing internal details. 
         FIG.  25    is a left side perspective view of the linear crossbow of  FIG.  21    in the drawn position further detailing the string connection points. 
         FIG.  26    is right side perspective view of the linear crossbow of  FIG.  21    in the undrawn position showing the detailed string connection and routing. 
         FIG.  27    is a right side perspective view of the linear crossbow of  FIG.  21    in the undrawn position showing the complete crossbow. 
         FIG.  28    is another linear crossbow with the limbs facing rearward with cams distally mounting and limb to limb power cables left side perspective view. 
         FIG.  29    is a top view of the linear crossbow of  FIG.  28    in the draw position. 
         FIG.  30    is a left side perspective view of the linear crossbow of  FIG.  28    detailing the internal components and string connections. 
         FIG.  31    is a left side perspective view of the linear crossbow of  FIG.  28    in the drawn position further detailing the string routing and connection points. 
         FIG.  32    is a right side perspective view of the linear crossbow of  FIG.  28    in the undrawn position and exposing some internal parts and details. 
         FIG.  33    is a right side perspective view of the linear crossbow of  FIG.  28    in the undrawn position detailing the string routing and connections. 
         FIG.  34    is another linear crossbow with the limbs facing rearward and the cams distally mounted to the limbs and the power cables centrally connected in the drawn position. 
         FIG.  35    is a left side perspective view of the linear crossbow of  FIG.  34   . 
         FIG.  36    is a bottom side perspective view of the linear crossbow of  FIG.  34    details the cam connection and string routing. 
         FIG.  37    is a top view of the linear crossbow of  FIG.  34    in the draw position. 
         FIG.  38    is a bottom view of the linear crossbow of  FIG.  34    in the drawn position. 
         FIG.  39    is a left side perspective view of the linear crossbow of  FIG.  34    in drawn position showing internal components. 
         FIG.  40    is a left side perspective view of the linear crossbow of  FIG.  34    in drawn position detailing the string routing and connection points. 
         FIG.  41    is a perspective view of the linear crossbow of  FIG.  34    in the undrawn position showing the bottom side. 
         FIG.  42    is a perspective view of the linear crossbow of  FIG.  34    in undrawn position detailing the string routing and connection points. 
         FIG.  43    is a perspective view of PRIOR ART showing how scope mounts are currently used in two methods. 
         FIG.  44    is a right side view of PRIOR ART showing the scope mounts must be clear of the draw string path. 
         FIG.  45    is a right side view of PRIOR ART showing the scope mounts and arrow path. 
         FIG.  46    is a left side perspective view showing details of the scope rail mount that is side mounted along the flight path and does not interfere with the arrow or draw string. 
         FIG.  47    is a right side view of the scope rail setup of  FIG.  46    detailing the scope mount setup in multiple positions and some detailed dimensions. 
         FIG.  48    is a perspective view of the scope mount setup of  FIG.  46   . 
         FIG.  49    is a perspective view of the scope mount setup in multiple positions showing the power stroke clearance of the scope mount. 
         FIG.  50    is a perspective view of the arrow shuttle and various small projectiles and various attachment methods. 
         FIG.  51    is a side view of the rear take up and trigger and latch assembly in various position of fire, drawing, and loaded. 
         FIG.  52    is a side and perspective view of the power take up spiral track with let off. 
         FIG.  53    is another linear crossbow design with a pair of cams affixed to the stock and the limbs distally mounted in the rearward direction with the power cables attached to the end of limbs and then to the fixed central cams shown in the drawn position. 
         FIG.  54    is a left perspective view of the linear crossbow shown in  FIG.  53    in the drawn position and a partial cut away view of the stock to display the inner working components. 
         FIG.  55    is a left perspective view of the linear crossbow of  FIG.  53    exposing the inner working and string connection points in the drawn position. 
         FIG.  56    is a bottom perspective view of the linear crossbow of  FIG.  53    exposing the inner working of the linear crossbow in the drawn position. 
         FIG.  57    is a top view of the linear crossbow of  FIG.  53    detailing the operation of components in the drawn position. 
         FIG.  58    is a bottom perspective view of the complete linear crossbow in the drawn position. 
         FIG.  59    is a top perspective zoom view of the linear crossbow of  FIG.  53   . 
         FIG.  60    is a left side perspective view of the linear crossbow of  FIG.  53    in the undrawn position. 
         FIG.  61    is a left perspective view of the linear crossbow of  FIG.  53    in the undrawn position with exposed stock portion to view inner workings. 
         FIG.  62    is a left perspective view of the linear crossbow of  FIG.  53    in the undrawn position showing the string routing details. 
         FIG.  63    is a left perspective view of the linear crossbow of  FIG.  53    in the undrawn position showing further details of the string routing. 
         FIG.  64    is a top view of the linear crossbow of  FIG.  53    in the undrawn position. 
         FIG.  65    is a bottom perspective view of the linear crossbow of  FIG.  53    in the undrawn position. 
         FIG.  66    is a bottom perspective view of the linear crossbow of  FIG.  53    in the undrawn position removing the stock to detail the inner components. 
         FIG.  67    is a bottom perspective view of the linear crossbow of  FIG.  53    in the undrawn position with the string routing details exposed. 
         FIG.  68    is a left perspective view of the crossbow of  FIG.  53    in the undrawn position and the limb and cams REVERSED to show the same design can be flipped if desired. 
         FIG.  69    is a left perspective view of the crossbow of  FIG.  28    in the undrawn position with the limbs, cams, and idlers REVERSED to show the same design can be flipped if desired. 
         FIG.  70    is a left perspective view of the crossbow of  FIG.  34    in the undrawn position with the limbs, cams, idlers REVERSED to show the same design can be flipped if desired. 
     
    
    
     DETAILED DESCRIPTION 
     Various embodiments will be described in detail with reference to the drawings, wherein like reference to numerals represent like parts and assemblies throughout the several views. Reference to various embodiments does not limit the scope of the claims attached hereto. Additionally, any examples set forth in this specification are not intended to be limiting and merely set forth some of the many possible embodiments for the appended claims. 
     According to the principles of the present disclosure, limb, stock, draw string, latch and tensioning systems, referred to herein as a linear crossbow, include configurations that provide various advantages over prior art crossbows using prior art for limb configurations and various cam systems. 
     The linear crossbow can be designed using various limb arrangements, draw string let out means and or cam arrangements to reduce shock, improve efficiency, improve balance, improve safety, shoot different projectiles, and improve accuracy. The linear crossbow may include one or more of the following features: 1) Limbs mounted forward vertically parallel to draw string. 2) Parallel Limbs rear facing 3) Parallel Limbs forward 4) Dual string let out track with dual cams 5) Dual string let out with center mounted power cables 6) Scope sight mount that spans the stock side to side 7) Various Projectiles and Interchangeable mounts 8) Fixed or Drop away rest system 9) Rear take up latch, trigger and variable power stroke 10) Fixed Central Cams. Any one of the aforementioned items provide new improvements over prior art technologies, and, alone or combined, produce improvements to prior art crossbows. By combining various elements, a linear crossbow can be produced that is narrower, more accurate, more efficient and safer to operate. 
     The linear crossbows shown in  FIGS.  1    thru  70  all show the linear crossbow using dual draw strings to improve stability of the arrow shuttle, however, a single draw string and a shuttle attached in a similar fashion could be performed and would function as well. Also, a shuttle guide could be used to support the shuttle but would likely decrease the efficiency of the linear crossbow. Likewise, the types of cams shown can be any number of cams known or limb arrangements that have been used on other crossbow and bow designs. 
     Section 1—Limbs Mounted Forward Vertically Parallel 
       FIGS.  1 - 10    illustrate an example of a linear crossbow according to the principles of the present disclosure. 
     The limbs  7 F and  7 B can either be a single limb or a split limb set and are shown as a single limb set. The limbs  7 F and  7 B have a unique orientation in relation to the stock such that they are positioned along the side and upward of the stock  6 . The limbs  7 F and  7 B are oriented to create a very narrow crossbow with a width of distance  9 D that is below 8 inches and preferably around 3 inches. The limbs  7 F and  7 B are distally mounted in the forward direction and the fixed ends are affixed by  6 F and  6 B which are affixed to stock  6 . 
     The limbs  7 F and  7 B are also supported over mid limb supports  11 F and  11 B to provide a moment for the limbs to flex over. The mid limb supports  11 F and  11 B are also affixed to the stock  6  as shown. The limbs  7 F and  7 B free ends have power cables  3 F and  3 B that are affixed to the free limb ends at point  22 F and  22 B and to the forward string let out track assembly  12 . 
     Furthermore, assembly  12  has dual spiral take up tracks  2 F and  2 B that take up power cables  3 F and  3 B that are attached to at points  3 AF and  3 AB. The forward string let out track assembly  12  has dual string let out grooves with the draw strings  1 F and  1 B attached and wrapped one revolution in the undrawn state and are attached at points  12 AF and  12 AB. The  12  forward string let out assembly is also rotatably mounted to stock  6  with bearings and axle  88  to allow assembly  12  to freely rotate and supports the power cable loads that can be in excess of 1000 lbs. 
     The draw strings  1 F and  1 B after wrapping one revolution are then directed over the stop pulley  44  then directed towards the rear take up string tracks of assembly  14  and the draw string  1 F and  1 B are attached in corresponding grooves at points  14 AF and  14 AB. The stop pulley  44  is rotatably mounted to the stock  6  with an internal bearing assembly and freely spins on axle  45 . The purpose of  44  stop pulley is critical in the operation of the design in order to stop the rotation of the  14  assembly without free-wheeling and losing tension. 
     The assembly  14  contains dual string grooves to take up the draw strings  1 F and  1 B when assembly  14  is ratcheted up using detachable handle crank  15  with the toothed side mounts  17  and  18  of assembly  14  interacting with the latch assembly  19 . The latch assembly  19  pivots about bearing axle point  66  and the trigger assembly  20  pivots about axle point  67 . The ratchets or toothed sides of  14  contain  17  and  18  that lock the take up mechanism during the drawing of the linear crossbow until the trigger of the trigger assembly  20  is depressed disengaging claws of the latch assembly  19  from the teeth of  17  and  18  thus firing the crossbow. 
     The trigger assembly  20  and the latch assembly both have springs  77  and  78  that bias the position shown in  FIG.  3   . The rear take up assembly  14  is rotatably mounted to the stock  6  with bearings and axle  89  allowing  14  to freely and efficiently rotate. The entire assembly axle  89  has a receptacle to accept the detachable handle crank  15  and ratchet the assembly to the drawn position. The trigger assembly  20  interacts with  19  latch assembly such that when trigger of the trigger assembly  20  is depressed the  19  latch disengages and allows the loaded draw strings  1 F and  1 B to transfer by being pulled by the forward string let out assembly  12  while limbs  7 F and  7 B are unloading and concurrently pulling on power cables  3 F and  3 B causing the  12  forward let out track to quickly wind strings  1 F and  1 B up and unload string portion that was wound on rear take up track assembly  14  until all the draw strings  1 F and  1 B reach where they are attached and causing unwinding to stop by using the  44  stop pulley. 
     The arrow shuttle  33  is affixed to draw strings  1 F and  1 B and is located such that in the at rest position and the fully cocked position it remains along the straight path between  12  and  14 . The arrow attachment post allows the arrow  55  to be nocked on the arrow shuttle  33  and the forward portion of the arrow  55  is supported by the arrow rest  56 . The shuttle  33  is only supported by the draw strings  1 F and  1 B and has no frictional loss from being guided on a track. The power stroke PS is typically 14 inches but can be between 1 inch to 30 inches since the design allows for very long power strokes. 
     The diameter of  12  and  14  respectfully have a circumference that is equal or great than the desired power stroke PS. The diameter of  12  and  14  are around 4.7 inches but can be between 1 and 8 inches. The string grooves tracks of  12  and  14  are linear and a single rotation; but could also be spiral or stacked allowing significantly more draw string to be spooled and make the track diameters smaller and still provide enough payout for a power stroke of 6 to 30 inches. The reasoning for  12  and  14  being a single layer since it is the most efficient method for operation at the high speeds for shooting arrows  55 . 
     The forward spiral take up tracks  2 F and  2 B are shown circular in nature but could be noncircular and could also contain a let off portion to allow the holding weight at full draw to be near zero as shown in  FIG.  52   . The spiral track  2 F wraps the power cable  3 F around a circumference and as shown then  3 F 1  drops to a much smaller diameter to reduce the bias significantly on the string let out track assembly  12  and make the trigger of the trigger assembly  20  have a much lower pull needed to release the latch  19  for shooting. The let off for  3 F 1  can be from 0 to 100 percent and preferably around a 70 percent let off. 
     The trigger mechanism can include an auto safety and anti-dry fire protection but for ease of explanation they have been omitted here. Such items could easily be included. 
     The linear crossbow shown in the figures also shows a foot stirrup  99  that is mostly for safety of arrow and not needed as a cocking aid. The primary method of cocking the linear crossbow is using the detachable handle crank  15  that fits into a receiving socket of axle  89  that is directly connected to the rear take up assembly  14 . 
     The method of operation of the linear crossbow in detailed in  FIGS.  1    thru  10  showing the linear crossbow both the drawn and undrawn positions. In the undrawn positions the draw strings  1 B and  1 F are initially would around string let out assembly and attached to the rear take up assembly  14 . During the drawing cycle the limbs  7 F and  7 B are drawn down by power cables  3 F and  3 B as assembly  12  rotates thus letting out draw string  1 F and  1 B to the rear take up assembly  14  until the desired power stroke is reach and held by the latch means  20  of the rear take up assembly  14 . At the end of the draw cycle or drawn position the draw strings are wrapped around the take up assembly  14  as shown in the Figures and the string let out assembly has draw strings  1 F and  1 B at the end of the available draw string payout. The process repeats every time the linear crossbow is fired and drawn again. The attachments of arrow shuttle is a post with an diameter of about 0.115 inches matching the diameter of most draw strings used today thus mimicking a draw string connection. The connections means or arrow shuttle  33  could be any type of connection means for arrows or other projectiles. 
     Section 2—Parallel Limbs Rear Facing 
     Another example configuration of the linear crossbow is shown in  FIG.  11    through  FIG.  20   . In this example, the linear crossbow has a few additional components to redirect the power cables from the limb tips to the power tracks on the forward string let out tracks. Furthermore, this design has rearward facing and near parallel limb arrangement that will significantly reduce recoil and shock after the shot. The layout of the limbs and the additional guide pulleys are the main difference from the linear crossbow shown in  FIGS.  11    thru  20 . The details described will focus primarily on the limbs and pulleys and the rest will be understood to be similar or the same as the prior design described in Section 1. 
     The following details describe the design for this linear crossbow starting with the limbs. The limbs  177 F and  177 B can either be single or split limbs design, also the limbs  177 F and  177 B are attached to a forward riser  180  section and are distally mounted from riser  180  and the riser  180  is affixed to stock  60 . The limb  177 F and  177 B are affixed to riser  180  at point  160 F and  160 B. The limbs  177 F and  177 B are also supported over mid limb supports  111 F and  111 B to provide a moment for the limbs to flex over. The mid limb supports  111 F and  111 B are also affixed to the riser  180  as shown. The limbs  177 F and  177 B free ends have power cables  130 F and  130 B that are affixed to the free limb ends at point  122 F and  122 B. 
     The power cable  130 F and  130 B are then directed towards the guide pulleys  133  and  134 . Pulleys  133  and  134  are independently rotatably mounted to stock  60  and freely rotate about axle  115  which is rigidly mounted to the stock  60 . The power cables  130 F and  130 B are then directed towards the forward string let out track power take up spiral tracks at  102 F and  102 B and affixed at points  130 AF and  130 AB. 
     Furthermore, spiral tracks  102 F and  102 B are part of the forward string let out track assembly  112  which is rotatably mounted to the stock  60 . The string let out track assembly has draw strings  100 F and  100 B attached to  112  assembly at point  112 AF and  112 AB and in the undrawn state are wrapped about the circumference and then directed to the stop pulley  44  and then rear draw string take up assembly  114 . The draw strings  100 F and  100 B are attached to  114  assembly at  114 AF and  114 AB as shown. In the undrawn state arrow shuttle  33  is in the forward position and in the drawn position move back. 
     During the drawing cycle the limbs  177 F and  177 B are flexed as the assembly  112  is rotated causing draw strings  100 F and  100 B to payout to the rear take up assembly  114  and the limb power cables  130 B and  130 F pull on the limbs and are taken up by the rotation of forward string let out assembly  112 . The rest of the function of this design has been described above. 
     The overall width of the linear crossbow describes in  FIGS.  10    thru  20  can have a width between 3 inches and 24 inches depending on the angle of the limbs, but preferable in the range of about 8 inches in undrawn position. The power stroke of this design would be in the range of 1 to 30 inches and preferably around 15 inches. The arrow shuttle  33  is affixed to draw strings  100 F and  100 B such that going from the undrawn to drawn position the arrow shuttle moves about 14 inches in the direction of arrow flight and remains attached and under tension. 
     The basic premise of this design is using two limbs with independent power cables working a central or single string let out means using independently attached power cables that are directed to the same assembly biasing the forward string let out assembly  112  to resist letting out the draw strings  1 F and  1 B. The draw strings  1 F and  1 B payout and take up between  112  and  114  and repeat this process during the shooting and cocking of the linear crossbow. The linear crossbow also shows a scope mount  5  that is mounted to the sides of the stock anywhere along the length of the stock providing for a very rigid mount that allows the draw strings, arrow, and arrow shuttle to freely pass between and under the scope mount without interference to the travel of the mentioned. The power stroke PS with this design can between 1 and 30 inches and the arrow shuttle  33  moves between the forward and rearward string tracks. 
     Section 3—Parallel Limbs Forward Facing 
     Another example configuration of the linear crossbow is shown in  FIG.  21  through  27   . The linear crossbow shown here is very similar to the linear crossbow of section  2  but the limbs are pointing in the opposite direction shifting the weight and improving balance. Furthermore, this design has forward facing and near parallel limb arrangement that will significantly reduce recoil and shock after the shot. This linear crossbow design may balance better and pulls the riser weight further back. The layout of the limbs and the additional guide pulleys are the main difference from the linear crossbow shown in  FIG.  1    thru  10 . The details described will focus primarily on the limbs and pulleys and the rest will be understood to be similar or the same as the prior design described in Section 1. 
     The following details describe the design for this linear crossbow starting with the limbs. The limbs  277 F and  277 B can either be single or split limbs design, also the limbs  277 F and  277 B are attached to a rearward riser  280  section and are distilling mounted from riser  280  and the riser  280  is affixed to stock  250 . The limb  277 F and  277 B are affixed to riser  280  at point  260 F and  260 B. The limbs  277 F and  277 B are also supported over mid limb supports  211 F and  211 B to provide a moment for the limbs to flex over. The mid limb supports  211 F and  211 B are also affixed to the riser  280  as shown. The limbs  277 F and  277 B free ends have power cables  230 F and  230 B that are affixed to the free limb ends at point  222 F and  222 B. 
     The power cable  230 F and  230 B are then directed towards the forward guide pulleys  233  and  234 . Pulleys  233  and  234  are rotatably mounted to stock  250  and freely rotate about axle  215  which is rigidly mounted to the stock  250 . The power cables  230 F and  230 B are then directed towards the forward string let out track power take up spiral tracks and  202 F and  202 B and attached at point  230 AF and  230 AB. 
     Furthermore, spiral tracks  202 F and  202 B are part of the forward string let out track assembly  212  which is rotatably mounted to the stock  250 . The string let out track assembly  212  has draw strings  200 F and  200 B affixed at points  200 AF and  200 AB and in the undrawn state as shown in  FIG.  26    are wrapped about the circumference and then directed to the stop pulley  44  then the rear draw string take up assembly  214  and attached to  214  at points  214 AB and  214 AF. The draw string  200 F and  200 B also have the arrow shuttle  33  attached such that during the drawing and undrawing the arrow shuttle  33  moves about 14 inches or the power stroke distance propelling the arrow. The rest of the function of this design has been described above. 
     The overall width of the linear crossbow described can have a width between 3 inches and 24 inches depending on the angle of the limbs, but preferable in the range of about 6 inches in undrawn position. The power stroke of this design would be in the range of 1 to 30 inches and preferably around 15 inches. The arrow shuttle  33  is affixed to draw strings  200 F and  200 B such that going from the undrawn to drawn position the arrow shuttle moves about 14 inches in the direction of arrow flight and remains attached and under tension. The operation of the described linear crossbow is nearly identical to the crossbow of section  2  other than the limb direction or orientation. The PS power stroke is shown in  FIG.  26    and runs between the forward tracks of  212  and the rearward take up assembly  214  and can between 1 and 30 inches and preferably around 14 inches. 
     Section 4—Dual String Let Out Track with Dual Cams 
     Another configuration of the linear crossbow is shown in  FIG.  28    through  FIG.  33   , and  FIG.  69    reversed option. The linear crossbow uses a set of cams which are distally mounted to the free ends of the limbs, then are timed together to generate the power and let off means similar with compound crossbows used today. The biggest difference is that the draw string is two draw strings that are directed around pair of pulleys, then to the rear take up track assembly. The layout of the limbs and the additional guide pulleys and cams mounted to end of the limbs are the main difference from the linear crossbow shown in  FIG.  1    thru  10 . The limbs of this design could also have the limbs mount forward or rearward. 
     Furthermore, the designs of could use any number of currently available cam means or round cams with double Y yokes or any cam timing arrangement known in the prior art with or without let off. The details describe will focus primarily on the limbs, pulleys, cams and the rest will be understood to be similar or the same as the prior design described in Sections 1, 2, and 3. 
     The following details describe the design for this linear crossbow starting with the limbs. The limbs  377 F and  377 B which can either be single or split limbs design, also the limbs  377 F and  377 B are attached to a forward riser  380  section and are distally mounted from riser  380  and the riser  380  is affixed to stock  60 . The limb  377 F and  377 B are affixed to riser  380  at point  360 F and  360 B. The limbs  377 F and  377 B are also supported over mid limb supports  311 F and  311 B to provide a moment for the limbs to flex over. The mid limb supports  311 F and  311 B are also affixed to the riser  380  as shown. The limbs  377 F and  377 B free ends have cams  330 F and  330 B that are rotatably mounted to the free limb ends at axles  322 F and  322 B. The current design shows a cam to cam power cable arrange with power cables  317  and  318  attached to corresponding take up and let out tracks from prior art known. 
     The power cables  317  and  318  maintain the timing and providing let off at the end of draw cycle. They are arranged in this design in what is known as a binary cam arrangement with  317  being attached to cam  330 AF at point  317 AF take up track and then to cam  330 AB and attached at point  317 BF to a let out track. Power cable  318  is attached to cam  330 AF at point  318 AF that is a let out track and the other end of  318  is attached to cam  330 B at point  318 BF which is a take up track. 
     Again, the timing portion is not critical with the linear crossbow since the draw strings  300 F and  300 B are drawn along a linear path from a single take up assembly  314 . The power or bias the draw strings in this design is provided between the limbs and is commonly used in many crossbows. The cams  330 F and  330 B are biased to take up the draw strings  300 F and  300 B such that when rear take up assembly  314  is rotated or pulled the string track payout or unload to the  314  take up assembly but resist and create a draw force curve that builds the load and hold the force on the draw string  300 A and  300 F until they reach the end of the power stroke and then let out the load ready to fire position. Yet again, the type or style of the cam arrange can be any type used in prior art. 
     Furthermore, one main advantage is that the power cables  317  and  318  do not require that they are directed and are not in the arrow flight paths as with other crossbow on market thus reducing cable wear and improving safety and efficiency. They are freely floating below the draw strings  300 F and  300 B and do not interfere with the arrow  55  flight or arrow shuttle  33 . The cams  330 F and  330 B both have string let out tracks and in the undrawn position have draw strings  300 F and  300 B that are wrapped around the circumference of the cam tracks and attach at point  330 AF and  330 AB and the draw strings are then directed to the two draw string guide pulleys  333  and  334 . 
     Draw string guide pulleys  333  and  334  are rotatably mounted to stock  60  and freely rotate about axle  315  and  316  and these axles are rigidly mounted to the stock  60 . The draw strings  300 F and  300 B are then directed to the stop pulley  44  and then onto the rear draw string take up assembly  314  and the draw strings are attached at point  314 AB and  314 AF. The rear take up assembly is rotatably mounted to the stock  60  with a set of bearing about an axles  89 . The axle  89  also contains a mating point to accept a ratchet or handle crank  15 . 
     The rest of the function of this design has been described above in Section 1, 2, and 3. The axle to axle width of the linear crossbow described can have a width between 5 inches and 24 inches depending on the angle of the limbs, but preferable in the range of about 8 inches in undrawn position. The power stroke PS of this design would be in the range of 1 to 30 inches and preferably around 15 inches. The arrow shuttle  33  is affixed to draw strings  300 F and  300 B such that going from the undrawn to drawn position the arrow shuttle moves about 14 inches in the direction of arrow flight and remains attached and draw strings  300 A and  300 B remain under tension. To increase the power stroke the size of cams can be larger or spiral wound or any other method of providing draw string. The distance FP of the fixed idlers pulleys  334  and  333  can be forward as shown or rearward of the cams  330 B and  330 F. The ideal position of the FP distance is plus or minus 6 inches of the cams and is shown at about 4 inches forward of the cams to maximize the power stroke PS. 
     The system can even use a single cam system known in vertical bows and an idler pulley. Any of the cam arrangement know in the art can be used, but simply taking the draw string and separating the draw string from a cam to cam connection but instead using a cam to pulley to rear take up system arrangement for the draw strings is the main design feature of the described linear crossbow. 
     The draw strings  300 F and  300 B could be combined into one draw string after leaving the guide pulleys  333  and  334  and then directed to a single groove track on the rear take up assembly  314 . The design of the linear crossbow is unaffected by cam lean since the draw string is guided and moves between to rotatably mounted point and is extremely accurate. Finally, the draw strings could come off the rear or forward side of the cams and the idler pulleys  315 / 316  could be forward or rearward of the cams, the method shown is the preferred method. Another variation of the crossbow is shown in  FIG.  69    that show the limbs and cams reversed in the opposition direction. The design of  FIG.  69    will pull more weight rearward and possibly balance better. The  FIG.  69    uses like numbers the same as described above to allow someone to easily follow this design. 
     Section 5—Dual String Let Out with Center Mounted Power Cables 
     Another example configuration of the linear crossbow is shown in  FIGS.  34  through  42   , and  FIG.  70    reverse option. The linear crossbow uses a set of cams which are distally mounted to the free ends of the limbs. The cams power cables are then directly mounted to the stock portion and independently operate. 
     The biggest difference is that the draw string is dual draw strings that are directed around pair of pulleys, then to the rear take up track assembly. The timing of the cams in the linear crossbow of  FIGS.  34  to  42    are not an issue since the draw strings are pulled from the center from a single take up track assembly. The layout of the limbs and the additional guide pulleys and cams mounted to end of the limbs are the main difference from the linear crossbow shown in  FIG.  1    thru  10 . The limbs of this linear crossbow could also have the limbs mounted forward or rearward. Furthermore, the linear crossbow could use any number of currently available cam means or round cams known in the art with or without let off. The details described will focus primarily on the limbs, pulleys, cams and the rest will be understood to be similar or the same as the prior designs described in Section 1, 2, 3, and 4. 
     The following details describe the design for this linear crossbow starting with the limbs. The limbs  477 F and  477 B can either be single or split limbs design, also the limbs  477 F and  477 B are attached to a forward riser  480  section and are distally mounted from riser  480  and the riser  480  is affixed to stock  60 . The limb  477 F and  477 B are affixed to riser  480  at point  460 F and  460 B. The limbs  477 F and  477 B are also supported over mid limb supports  411 F and  411 B to provide a moment for the limbs to flex over. The mid limb supports  411 F and  411 B are also affixed to the riser  480  as shown. The limbs  477 F and  477 B free ends have cams  430 F and  430 B that are rotatably mounted to the free limb ends at axles  422 F and  422 B. 
     The current design shows a cam to stock connection of power cables arranged with power cables  417  and  418  attached to corresponding take up power tracks on cams  430 F and  430 B and the other end attached to the stock at point  486  and  487 . The power cables  417  and  418  take up power cable during draw cycle and bias the draw string to the undrawn state while flexing the limbs  477 F and  477 B creating a draw force curve to propel the arrow  55 . The power cable  417  has one end attached to the power cable take up track of cam  430 B and is attached at point  417 A with the other end of  417  is attached at point  486  that is attached to the stock  60 . The other power cable  418  has one end attached to the power cable take up track of cam  430 F and is attached at point  418 A with the other end of  418  attached at point  487  that is attached to the stock  60 . Again, the timing portion is not critical with this linear crossbow since the draw strings  400 B and  400 F are drawn along a linear path from a single take up string assembly  414 . 
     The power or bias to the draw strings in this design is provided between the limbs and riser and is commonly used in crossbows. Furthermore, one main advantage is that the power cables  417  and  418  are not in the arrow flight paths as with other crossbows on market thus reducing cable wear and improving safety and efficiency. The cams  430 F and  430 B both have string let out tracks and in the undrawn position have draw strings attached at point  400 AF and  400 AB then  400 F and  400 B are wrapped around the circumference of the cam string tracks and the draw strings are then directed to the two draw string guide pulleys  433  and  434 . Draw string guide pulleys  433  and  434  are rotatably mounted to stock  60  and freely rotate about axle  415  and  416  and the axles are rigidly mounted to the stock  60 . 
     The draw strings  400 F and  400 B are then directed to the stop pulley  44  and then onto the rear draw string take up assembly  414 . The stop pulley is rotatably mounted to the stock with axle  45  and spins freely. The draw strings  400 F and  400 B are attached to the rear take up assembly at point  400 AB and  400 AF. During the drawing and undrawing of the linear crossbow the arrow shuttle  33  move along a linear path or the power stroke of the linear crossbow which is about 14 inches. Furthermore, the draw strings  400 B and  400 F are biased to remains loaded on the string let out track but payout the retained draw string to the rear take up assembly  414  when the assembly is ratcheted using a ratchet or handle crank  15  to take up the string until the majority of the draw string moves to the take up assembly. 
     During the shooting or undrawing of the linear crossbow the draw strings are quickly unloaded from the take up assembly to the let out assembly moving the arrow shuttle  33  and propelling the arrow  55 . The process repeats while the linear crossbow is loaded, cocked, and fired. The rest of the function of this design has been described above in Section 1, 2, 3, and 4. 
     The axle to axle width of the linear crossbow described can have a width between 5 inches and 24 inches depending on the angle of the limbs, but preferable in the range of about 7 inches in undrawn position. The power stroke PS of this design would be in the range of 1 to 30 inches and preferably around 15 inches. The arrow shuttle  33  is affixed to draw strings  400 F and  400 B such that going from the undrawn to drawn position the arrow shuttle moves about 15 inches in the direction of arrow flight and remains attached and under tension. The position of the idler roller guide pulleys  433  and  434  are shown forward of the cams  430 F and  430 B and denoted as distance FP and is in the range of plus or minus 6 inches either forward or behind the cams. The FP distance shown is about 4 inches forward and is positioned to maximize the power stroke PS. The further forward the idler guide pulleys  433  and  434  are the more compact the linear crossbow can be made. 
     To increase the power stroke the size of cams can be larger or spiral wound or any other method of providing draw string. Any of the cam arrangements known in the prior art can be used, but simply taking the draw string and separating the draw string from a cam to cam but instead to a cam to pulley to rear take up system for both cams is the main unique technique of the described embodiment. The draw strings  400 F and  400 B could be combined into one draw string after leaving the guide pulleys  433  and  434  and then directed to a single groove track on the rear take up assembly  414  and the arrow shuttle could be attached to a single draw string but may require some guiding. 
     The example described above is the preferred method of operation. Also, the draw strings  400 F and  400 B can come off the forward part of the cams  430 B and  430 F as shown or the back side of the cams towards the buttstock. The ideal location for the most compact and efficient operation is shown forward of the cams for  433  and  434  idlers. The details of the linear crossbow shown in  FIG.  70    are the same as the above described but as shown in detail the limbs and cams are reversed and the limbs are pointing in the forward direction. The design of  FIG.  70    would shift more weight rearward and possibly balance better than the design described above. The numerals are the same as those used to describe the normal and reverse design in  FIG.  70    to allow the reader to easily follow the differences in the two design. 
     Section 6—Scope Sight Mount that Spans the Stock Side to Side 
     Another key feature of all the linear crossbows described thus far described is the ability to position the scope rail anywhere along the linear path of the stock or along the power stroke. We will use  FIGS.  43  to  49    to describe this feature in more detail. 
     Historically crossbow sights on prior art are cantilevered from behind the string latch forward. This cantilevered sight/scope rail is easily misaligned or moved when the crossbow is accidentally bumped or jarred. Some crossbows have incorporated dual mounted scope sight rails mounting them at the string latch and at a forward position in front of the perpendicular draw string at rest location. The reason that all current crossbows use this method of mounting the scope sight rails is that the draw string will clearly intersect or interfere with the traversing draw string requiring the sides of the stock barrel to be free and clear of any mount. 
       FIGS.  43 - 45    illustrate the prior art methods. The Prior Art shown with a stock  555  and a rear string latch position of  506  and a at rest string position of  530  must remain clear along the side of the power stroke or arrow flight path. Therefore, the scope rail mount  510  is cantilevered as shown. The arrow  55  and the draw string must not have any interference when the crossbow is fired. 
     The figure in  43  lower part shows the dual mounted sight scope rail mount  510  with forward portion  520  making it a dual point mount. The forward portion  520  down straddle the rail or barrel but can only do this is a position that is forward of the draw string and the area between points  505  and  540  must remain clear for the entire power stroke distance  600  and  601  respectfully. Both of the above scope rail mounts must keep the entire power stroke or draw string travel area clear of the arrow  55  and the draw string. 
     Turning our attention to  FIGS.  46  through  49    will show the proposed and unique scope rail mount  5  and the unique features. The scope sight mount  5  can straddle both sides of the stock anywhere along the length of the stock. Also, if the scope rail mount was the full length of the power stroke it would completely protect the shooter from ever touching the arrow or shuttle or draw strings making a safety guard and a scope rail mount. 
     The scope sight mount distance  62 D from the buttstock to sight scope mount  5  is shown as  62 D. This distance can be from 4 to 25 inches but preferably from 8 to 18 inches and ideally 10 to 12 inches. The length of the scope rail mount  5  is shown as  65 D and is in the range of 0.5 to 24 inches and is preferably 1 to 6 inches and is ideally 4 inches. The scope rail mount  5  can include a picatinny rail or be a smooth top with holes to accept any number of sight scope mounts. The internal clearance height of the scope sight mount  5  is above the arrow  55  as shown as  63 D and is in the range of 0.5 to 4 inches and preferably 1.5 inches. The scope rail mount  5  internal width clearance  64 D is shown and is in the range of 0.25 to 4 inches and preferably 1.5 inches and must be wide enough to allow arrow  55  and vanes to clear without contact. The scope sight mount assembly  5  can also have multiple mount locations along the barrel allowing the user to adjust the eye relief since the scope rail assembly  5  does not interfere with the  1 B and  1 F draw strings or the arrow  55 . 
     Furthermore, the scope mounting holes  38 ,  39 ,  40 ,  41  can have numerous locations as shown with additional holes  50 ,  51 ,  52 , and  53  or the scope sight rail  5  could be placed on a linear slide mechanism. The scope rail mounted in position  5 R is shown in a rear position and  5 F show the scope rail mounted in a forward position. The main advantage of this type of scope rail mount is the rigidity it provides for extreme accuracy and the ability to change the eye relief for the shooter without effecting accuracy by having to cantilever or dual mount a scope rail adding significant weight. Obviously, the scope rail mount  5  can also be single side mounted to one side of the stock and is shown as scope rail mount  54  and still provide for a very rigid mount. The scope rail mount  5  or  54  must be above the draw strings  1 F and  1 B, the arrow  55  and vanes, and the arrow shuttle  33 . 
     The described scope rail mount has never been able to historically be used on present day crossbows and will significantly improve the benefits of the linear crossbow. Finally, the scope rail mounts  5  and  54  defined provide for the most accurate and lightest assembly with eye relief adjustment to be used on a linear crossbow. The scope rail mounts  5  and  54  will work on any of the linear crossbows described in Sections 1 thru 9 as well as any other type of projectile weapon that uses a linear type of draw string assembly. 
     Section 7—Various Projectiles and Interchangeable Mounts 
     Some examples of the linear crossbow have yet another advantage over prior crossbows in the ability to not only shoot arrows or even large diameter arrows, but round shot, drones, missiles, small short arrows, spears, darts, grenades, cell phones, smoke canisters, and any number of projectiles that can be adaptably mounted to the draw string  1 F and  1 B of any of the designs described in Sections 1 thru 9. The projectiles can also be attached to a string for spear gun fishing or underwater use. 
       FIG.  50    shows only a few of the potential mounting options to shoot various projectiles. The projectiles launched will be in the weight range of 20 grains to 50 lbs and preferably 200 grains to 600 grains for most applications. The arrow mount shuttle  33  shown has a vertical post that duplicates the mounting means for attaching a standard arrow with a post that is 0.115 inches in diameter ideally. 
     The mount  781  shown is a receptacle mount that contains a small magnet that allows a steel round shot  780  to be held and then released at the end of the power stroke. Another mount  771  could also be to launch a dart  770  that is held with a rear mounted magnet. Another mounting method would use dual shuttles like shuttles  33  and  34  or this could be a single long shuttle that is about 0.5 to 8 inches long. 
     The spacing of shuttle  33  and  34  could be from 0.5 to 8 inches apart and preferably about 4 inches. The short arrow  795  shown can be from 2 to 12 inches and preferably about 6 inches. When using a short projectile that is either single or dual mounted the forward drop away or fixed arrow rest  56  is not required since the projectile is already supported. The arrow shuttle  33  and arrow  55  along with the forward arrow rest  56  is one of many ways to use the linear crossbow. 
     The methods described above are advantageous and can quickly and easily be interchanged either by mechanical means or a quick-change adaptable head to allow going from small short projectile to arrows within seconds. Since the linear crossbow has at least one and preferably two linear draw strings any number of mounts can be placed on the draw string  1 F and  1 B rigidly attached to accept any number of projectiles, as long as the projectile mounts stay between the draw string let out and draw string take up tracks during cocking and shooting of the linear crossbow. Current crossbows have projectile that usually have a single draw string and a draw string latch that engages the draw string and would interfere or be very difficult to interchange projectile types. The linear crossbow is ideal for this type of application. 
     Section 8—Fixed or Drop Away Rest System 
     The linear crossbows described above may use some type of forward arrow rest  56  and contains a standard mount  57  that will accept any number of arrow rests available on the market. The linear crossbow is unique in that the drop away rests can use the power cables of the design shown in  FIGS.  1    thru  10  and since the limbs and power cables are positioned as such that attaching the drop away power cord could be easily achieved. 
     Furthermore, the linear crossbow designs could contain addition take up or let out tracks to feed or take up a drop away power cord to allow the rest to function as on a vertical bow. 
     Finally, the linear crossbows shown by allowing any number of rests and having the arrow  55  supported between  33  arrow shuttle and  56  arrow rest the linear crossbow can be easily paper tuned to obtain perfect arrow flight by independently adjusting the arrow rest  56  up down left or right since it is mounted via standard mount  57  holes. 
     Section 9—Rear Take Up Latch, Trigger, and Variable Power Stroke 
       FIG.  51    shows details of examples of the rear take up assembly and trigger assembly. The linear crossbow is unique in that it does not engage the draw strings  1 B and  1 F or the arrow shuttle  33  or the arrow  55  to hold the linear crossbow at full draw. The described system could hold onto or latch the arrow shuttle  33  but this would put stresses on the arrow latch that could potentially slide on the support and draw strings when under tension or holding the linear crossbow in the drawn position. 
     Unlike prior art the crossbow interacts with the rear draw string take up  14  that contains a toothed assembly  17  and  18  that interact with the latch mechanism  19  to hold the crossbow at every toothed position while it is cocked. Furthermore, the linear crossbow trigger can be discharged with the trigger assembly  20  at any locked position along the full draw cycle or power stroke PS, allowing the shooter to vary the power of the projectile shot. This is not the only way this linear crossbow could be used, as you could obviously engage and hold the arrow  55 , draw string  1 B or  1 F, or the shuttle  33  to hold the linear crossbow at full draw. 
     The disclosed method is a preferred method and allows for a very robust system for releasing the loaded weapon without wear and tear on the draw strings. Historically, the draw string is the preferred method to retaining a crossbow in the fully draw position; however, this causes severe wear on the draw string every time the crossbow is shot significantly reducing the life of the string and the safety. The new system trigger mechanism does not demonstrate a safety or anti-dry fire mechanism, but this could easily be added using any other method similar to prior art. Finally, having a trigger latch mechanism that can retains the crossbow at various power stroke position is very advantageous for shooting various projectiles or varying the power or kinetic energy of the projectile. 
     Section 10—Fixed Central Cams 
     Another configuration of the linear crossbow is shown in  FIGS.  53  through  67   , and  FIG.  68    a reverse option. The linear crossbow uses a set of cams which are rotatably mounted and affixed to stock and centrally mounted to straddle the arrow flight path. The centrally mounted cams power cables are then directly attached the free end of the distally mounted limbs. 
     The timing of the central cams in the linear crossbow of  FIGS.  53  to  68    is not an issue since the draw strings are pulled from the center from a single take up track assembly. The limbs of this linear crossbow could also have the limbs mounted forward or rearward. Furthermore, the linear crossbow could use any number of currently available cam means or round cams known in the art with or without let off. The details described here will focus primarily on the limbs, pulleys, cams and the rest will be understood to be similar or the same as the prior designs described in Section 1, 2, 3, and 4. 
     The following details describe the design for this linear crossbow starting with the limbs. The limbs  877 F and  877 B can either be single or split limbs design, also the limbs  877 F and  877 B are attached to a forward riser  880  section and are distally mounted from riser  880  and the riser  880  is affixed to stock  60 . The limb  877 F and  877 B are affixed to riser  880  at point  860 F and  860 B. The limbs  877 F and  877 B are also supported over mid limb supports  811 F and  811 B to provide a moment for the limbs to flex over. The mid limb supports  811 F and  811 B are also affixed to the riser  880  as shown. The limbs  877 F and  877 B free ends have one end of the power cables  817  and  818  affixed at points  822 B and  822 F as shown. 
     The pair of cams  830 F and  830 B are rotatably mounted to the stock  60  and a bracket  899  with a set of axles at points  815  and  816  and have bearing to reduce friction and improve efficiency. The distance of the cam to cam center is about 4 inches and depends on the size of the cams. The main design criteria is that the tangent point of both cams has a spacing that is close enough to allow the shuttle  33  to have an almost constant spacing of about 0 to 1 inches apart and ideally about 0.2″ apart for the draw string  800 B and  800 F. 
     The other opposite ends of power cables  817  and  818  are attached to the cams  830 F and  830 B at points  830 AB and  830 AF. The cams  830 F and  830 B have a power cable string track such that upon drawing of the linear crossbow the power cables are wrapped around the corresponding power cable take up groove on each cam. The power cables  817  and  818  take up the power cables during the draw cycle and bias the draw stings  800 F and  800 B to the undrawn state while flexing the limbs  877 B and  877 B creating a draw force curve to propel the arrow  55  and move the shuttle  33  between two points very quickly. 
     An arrow shuttle  33  is affixed to the pair of draw strings  800 F and  800 B such that it travels between the draw and undrawn position in a linear path along the arrow flight path between the cams  830 F and  830 B and the rearward take up assembly  814 . Again, the timing portion is not critical with this linear crossbow since the draw strings  800 B and  800 F are drawn along a linear path from a single take up string assembly  814 . The power or bias to the draw strings in this design is provided between the limbs and centrally mounted cams  830 B and  830 F and is commonly used in crossbows. 
     Furthermore, one main advantage is that the power cables  817  and  818  are not in the arrow flight paths as with other crossbows on the market thus reducing cable wear and improving safety and efficiency. Furthermore, the cables  817  and  818  are not guided further increasing the efficiency of this design. 
     The cams  830 F and  830 B both have string let out tracks and in the undrawn position have draw strings attached at point  800 AF and  800 AB, then  800 F and  800 B are wrapped around the circumference of the cam string tracks and the draw strings are then directed to the rear stop pulley  44  and then onto the rear draw string take up assembly  814 . The rear take up assembly is rotatably mounted with bearing about axle  89 . The rear take up assembly  814  has two string grooves and draw string attachment means. The rear take up assembly  814  also contains a ratcheting means or toothed assemblies  17  and  18  attached to the rear take up that interact with the latch mechanism  19  and trigger assembly  20 . The stop pulley is rotatably mounted to the stock with axle  45  and spins freely. The draw strings  800 F and  800 B are attached to the rear take up assembly  814  at point  800 AB and  800 AF. 
     During the drawing and undrawing of the linear crossbow the arrow shuttle  33  move along a linear path or the power stroke of the linear crossbow which is about 14 inches. Furthermore, the draw strings  800 B and  800 F are biased to remains loaded on the string let out tracks of the cams  830 F and  830 B but payout the retained draw string to the rear take up assembly  814  when the assembly is ratcheted using a ratchet attachment point on axle  89  to take up the string until the majority of the draw string moves to the take up assembly. 
     During the shooting or undrawing of the linear crossbow the draw strings are quickly unloaded from the take up assembly  814  to the let out assembly moving the arrow shuttle  33  and propelling the arrow  55 . The process repeats while the linear crossbow is loaded, cocked, and fired. The rest of the function of this design has been described above in Section 1, 2, 3, and 4. 
     The axle to axle width of the linear crossbow described can have a width between 5 inches and 24 inches depending on the angle of the limbs, but preferable in the range of about 7 inches in undrawn position. The power stroke PS of this design would be in the range of 1 to 30 inches and preferably around 15 inches. The arrow shuttle  33  is affixed to draw strings  800 F and  800 B such that going from the undrawn to drawn position the arrow shuttle moves about 15 inches in the direction of arrow flight and remains attached and under tension. To increase the power stroke the size of  830 B and  830 F cams can be larger or spiral wound or any other method of providing draw string. Any of the cam arrangements known in the prior art can be used, but simply taking the draw string and separating the draw string from a cam to cam but instead from a cam to rear take up system for both cams is the main unique technique of the this embodiment. 
     The draw strings  800 F and  800 B could be combined into one draw string after leaving the cams  830 B and  830 F and then directed to a single groove track on the rear take up assembly  814  and the arrow shuttle  33  could be attached to a single draw string but may require some guiding. The described above is the preferred method of operation. 
     The details of the linear crossbow shown in  FIG.  68    are the same as the above described but as shown in detail the limbs and cams are reversed and the limbs are pointing in the forward direction. The design of  FIG.  68    would shift more weight rearward and possibly balance better than the design described above. The numerals are the same as those used to describe the normal and reverse design in  FIG.  68    to allow someone to easily follow the differences in the two designs.