Abstract:
An improved floating rail system for mounting accessories on a firearm having a barrel including a chassis and a clamp adapted to attach the chassis about the barrel of the firearm. A plurality of elongate accessory mounting rails are attached to the chassis and extend parallel to an axis of the barrel. The accessory mounting rails are supported in the chassis radially spread apart from the barrel.

Description:
RELATED APPLICATIONS 
     This application claims the priority benefit under 35 U.S.C. §119(e) of U.S. provisional patent application Nos. 60/920,106 filed Mar. 26, 2007; 60/879,777 filed Jan. 10, 2007; and 60/879,897 filed Jan. 11, 2007. Each of the aforementioned applications is herein incorporated by reference in its entirety. 
    
    
     BACKGROUND 
     The present disclosure relates to a floating rail system providing a weapon accessory mount interface, including mounting rail structure such as a “Picatinny” interface (e.g., as per standard MIL-STD-1913) for use with a firearm. The system in accordance with this disclosure may be used for attaching a thermal sight system, rotating left/right camera system, video display system, quick changing power supplies, optical scopes, tactical flashlights, vertically extending handgrips, or other weapon-mounted accessories. 
     Conventional Picatinny rails require multiple clamps to attach to a firearm and lack attached power supplies. In addition even where power supplies are attached to the rail systems the rails do not contain circuits and conductors within the rail systems to provide power and to operate accessory devices. Thus, it would be desirable to provide a floating rail system with one clamping mechanism to the firearm which securely attaches the floating rail system and all attached devices to the firearm ensuring they are aligned with the barrel of the gun. In addition it would be desirable to have a power supply attached to the firearm to supply any necessary power to the attached accessory devices. Circuits and conductors built into the rail system are also desirable because it decreases the number of components required to run additional devices. The present device contemplates an improved floating rail system which overcomes the above-referenced limitations and others. 
     SUMMARY 
     An improved floating rail system is provided for a weapon which can accommodate multiple accessory devices and the power supply needed to operate them. Such accessory devices include laser and optical scopes, thermal sights, left and right rotating camera modules, a modular weapon video display system including a video control panel and a human-viewable display screen, handgrip units, and power supplies. The floating rail system is composed of a rear clamp and a top and bottom chassis, where the chasses connect and their exterior attaches to the interior of the rear clamp. The rear clamp enables the floating rail system to attach to the firearm and extend out over the firearm&#39;s barrel without making contact with it. Various fasteners and grips can be used to attach accessory devices to the floating rail system. Devices that require power supplies may contain contacts which enable them to create a circuit with the conductor on the modular rails or their fasteners or grips may contain the contacts. Once the device is secured to the modular rails it will have a power supply and be able to transmit signals to other devices attached to the modular rails. This improved floating rail system also contains rail insulators and an air gap between the chassis and the modular rails enabling the floating rail system to remain cooler to the touch due to the lengthened heating period thereby lessening the need for hand guards. Both the rail insulators and the air gaps allow the heat expelled from the barrel when the weapon is fired to be removed from the interior of the floating rail system without heating the exterior of the rail system. 
     One advantage of the floating rail system in accordance with the present disclosure resides in the circuitry which may be provided therewith, enabling power to pass to accessory devices from the power supply and enabling control signals to pass between various accessory devices. Such signals allow one accessory device to operate another without wires needing to travel between the two devices. For example a control signal actuator may be equipped with switches to send signals to control attached accessory devices. 
     Another advantage of the floating rail system in accordance with the present disclosure is its ability to prevent or reduce heating of the floating rail system when the weapon is fired. This increased heating time during firing lessens the need for hand guards as it takes more continuous rounds in a short period of time to heat the floating rail system. 
     Still further advantages and benefits of the present disclosure will become apparent to those of ordinary skill in the art upon reading and understanding the following detailed description of the preferred embodiments. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The invention may take form in various components and arrangements of components, and in various steps and arrangements of steps. The drawings are only for purposes of illustrating preferred embodiments and are not to be construed as limiting the invention. 
         FIG. 1  is an isometric view of a firearm using a floating rail system with attached laser sight, optical scope, thermal sight, weapon video display, and vertical handgrip. 
         FIG. 2  is an isometric view of a firearm using a floating rail system. 
         FIG. 3  is a side isometric view of the floating rail system. 
         FIG. 4  is an isometric view of the floating rail system illustrating the floating rail interface. 
         FIG. 5  is a partially exploded view of the floating rail system. 
         FIG. 6  is an enlarged, fragmentary, partially exploded view of the floating rail system depicted in  FIG. 5 . 
         FIGS. 7 and 8  are side isometric views of the floating rail system with an attached power transfer module and power supply. 
         FIG. 9  is an isometric view of the floating rail system with the power supply released from the power transfer module. 
         FIG. 10  is an isometric view of the floating rail system with an unattached power transfer module attachment. 
         FIG. 11  is an isometric view of the floating rail system with a control grip. 
         FIG. 12  is an isometric view with the floating rail system with a released control grip and control grip attachment. 
         FIGS. 13   a  and  13   b  are isometric views of a further embodiment floating rail system incorporating a signal junction box showing the control signals transferred through the floating rail system to interface with accessory devices using standard control connectors. 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
       FIG. 1  illustrates an exemplary floating rail interface  10  attached to a firearm  12 , such as a military or tactical weapon, with attached accessory devices. Such accessory devices include laser sight  14 , thermal sight  16 , optical scope  18 , a modular weapon video display system including a video control panel  20  and a human-viewable display screen  26 , handgrip unit  22 , and power supply  24 . Additional accessory devices can also be attached to the floating rail interface  10 , such as a left and right rotating camera module. 
     One method of attachment of accessory devices to the floating rail system  10  is a three point fastener  15  as described in U.S. provisional patent application No. 60/855,928 filed Nov. 1, 2006, or U.S. patent application Ser. No. 11/933,887 filed on Nov. 1, 2007, which applications are herein incorporated by reference in their entireties. In this manner, the optical scope  18  may maintain its bore sight when removed temporarily from the rail interface, e.g., for hand held use. 
     Once the laser sight  14  is attached to the floating rail system  10  it may be controlled by controls located on handgrip unit  22 . Handgrip unit  22  contains actuators for selectively actuating weapon-mounted accessories such as the laser sight  14 , additional accessories include flashlights, fire control systems, communication devices, and laser designators. These accessory devices may be mounted on any of Picattiny rails  30   a ,  30   b ,  30   c , and  30   d , and still be controlled by handgrip unit  22 . Handgrip unit  22  may be a bipod handgrip unit as described in U.S. patent application Ser. No. 11/651,743 filed Jan. 10, 2007, U.S. patent application Ser. No. 11/084,942 filed Mar. 21, 2005, or U.S. provisional application No. 60/555,279 filed Mar. 22, 2004. Each of the aforementioned applications is incorporated herein by reference in its entirety. 
     The video collected from the thermal sight  16  can be viewed using the weapon video display system composed of video control panel  20  and display screen  26 . The images collected from thermal sight  16  are fed to the human-viewable display screen  26  and are viewable thereon. The video control panel  20  enables the user to change the settings of display screen  26 . In addition the video control panel  20  enables the user to select which camera to view when multiple cameras are attached to the modular rails  30 . A power supply  24  provides the power needed for the video control panel  20  and display screen  26  as well as the cameras and any other devices needing power that are attached to the modular rails  30 . When the display screen  26  is not in use it can be folded flat to the video control panel  20  because the display screen  26  is hingedly or pivotally mounted to the video control panel  20 . 
       FIG. 2  shows the attachment of the floating rail system  10  mounted to firearm  12  without any accessory devices attached. The floating rail system  10  is shown in  FIGS. 3 and 4  and includes a chassis  11  having a top rail chassis portion  42 , a bottom rail chassis portion  60 , a left side rail chassis portion  43 , and a right side rail chassis portion  41 . The chassis  11  is secured about the fore-end portion of firearm  12  via a rear clamp  34  at the proximal end of the chassis  11 . The distal end of chassis  11  is cantilevered out from the receiver portion of firearm  12  and does not contact the barrel. The modular Picatinny rails  30   a ,  30   b ,  30   c , and  30   d  are secured to the top, bottom, left and right chassis portions, respectively. Rail air gaps  36  are created between the chassis portions and their respective modular Picatinny rails  30  allowing for air circulation in the interior compartment defined by the chassis  11 . 
     Recesses  46  may be formed in the chassis  11  to reduce the weight of firearm  12  and provide a greater air gap, thereby increasing the thermal insulating properties of floating rail system  10 . Axially extending conductors  38  enable power and control signals to pass from one circuit board  50  to the others to enable attached accessory devices to be powered and/or controlled. For example, the contacts  62  on the handgrip  22  are electrically coupled to one or more switches  23  on the handgrip unit  22  (See  FIG. 12 ). The actuation of one or more switches  23  on the handgrip unit  22  outputs a control signal to the control signal conductors in the circuit board  50 . 
     Referring now to  FIGS. 5 and 6  there is shown an exploded view of the floating rail system  10 . The exterior surface of rail chassis  11  is connected to the interior surface of rear clamp  34 . Chasses  11  has an interior t-shaped cavity where cables or wiring can be fed through without interfering with the barrel of firearm  12 . Flex circuit  40  is attached to the interior surface of the cavity of chassis  11  and cooperates with transfer blocks  44  to connect the conductors  38  on each of the circuit boards  50  on the rails  30   a ,  30   b ,  30   c , and  30   d  of the top, bottom, right, and left chassis portions  42 ,  60 ,  41 , and  43 , respectively, enabling accessory devices to transfer power and signals between each other. 
     Each of the top, bottom, right, and left chassis portions  42 ,  60 ,  41 , and  43 , respectively, of the floating rail system  10  contain a plurality of alternating longitudinally spaced transverse chassis channels  45  located along the firearm barrel axis. Recesses  46  are also located along the barrel axis of firearm  10 , however they sit on chassis  11  in between each of the top, bottom, right, and left chassis portions  42 ,  60 ,  41 , and  43 , respectively. Rail insulators  52  formed of a thermally insulating material such as fiberglass can be inserted into chassis channels  45  between the top, bottom, right, and left chassis portions  42 ,  60 ,  41 , and  43  and top, bottom, right and left modular rails  30   a ,  30   b ,  30   d , and  30   c , respectively, enabling them to reduce thermal transfer to the outer surface of the rails, thereby avoiding the need for hand guards. In addition the floating rail system  10  is helped to remain cool to the touch with additional cutouts  28  which are located on chassis  11 . Rail insulators  52  and modular rails  30  are secured to the chassis  11  by threaded fasteners  51  or the like. 
     A circuit board  50  is secured into the longitudinal rail channel  47  created on the exterior of the modular rails  30  covering threaded fasteners  51 . A plurality of mounting members  49  alternate with transversely-extending channels or grooves  39  in the Picatinny rail member  30 . The alternating mounting members  49  and grooves create a mounting surface for all accessory devices. Anchor blocks  48  are secured with fasteners  53  to the modular rails  30  to secure the circuit board  50  into place. Once the circuit board  50  is secured in place it makes contact with the top of transfer contact block  44  having conductive vias extending through the contact block  44  to the bottom of contact block  44 . Each conductive via makes contact with a corresponding conductor on a flex circuit  40 . The flex circuit  40  is secured to the interior surface of the chassis  11  via blocks  32 . Flex circuit  40  in turn provides the electrical connection between the circuit boards  50  in each of the Picattiny rails  30   a ,  30   b ,  30   c , and  30   d  via associated contact blocks  44 . The circuit board  50  thus provides an electrical power and signal coupling between attached devices and the power supply  24 . 
       FIGS. 7-10  show the attachment of the power supply  24  to the floating rail system  10 . Power supply  24  contains a quick release button  54  to enable the power supply to be quickly replaced when the power runs out. The power supply  24  is attached to floating rail system  10  via a power transfer module  56  which contains a mounting foot portion  59  and a rail grabber portion  61  for attachment to the Picattiny rails  30 . In order to prevent axial movement of the attached accessory devices while the weapon is being fired protrusions, such as mounting foot protrusion  70 , are added to mounting members to engage the transverse slots  72  created on Picattiny rails  30 . The mounting foot  59  complements mounting shoe  53  of power supply  24  securely attaching the power supply  24  to the Picattiny rails  30  and forming an electrical connection between power supply  24  and the circuit board  50 . Additional power supplies may be attached to power supply  24  via mounting shoe  25  located on the bottom of each power supply  24 . Thereby allowing the operator to have a power supply with a longer life or enabling the operator to attach additional power supplies to power supply  24  when the battery is running low or has run out. 
     The power supply  24  can be attached at any desired position on the floating rail system  10  to give the user more versatility in positioning and arranging the accessory devices. Alternatively, the power supply  24  may be of a quick change, bayonet-mount type shown and described in U.S. patent application Ser. No. 11/591,886 filed Nov. 1, 2006, the entire contents of which are incorporated reference. The power supply  24  may include a mounting shoe  25  for attaching additional like power supplies  24  and to provide an electrical (e.g. parallel) connection thereto. Alternatively power supply units may be used with an electrical adaptor which may be attached to the Picattiny rails  30 . The electrical adaptor enables the power supply to be located remotely and connected to the adaptor through an electrical cable. Remote power supplies may be located on the firearm  12 , such as mounted in the buttstock portion of the firearm, or worn or carried by the weapons operator. Still other alternatives may enable the power supply to be located on the firearm  12 , such as power supply  27  mounted in the firearms buttstock, and internally routed via conductors from the remote location to the floating  5  rail system, e.g., through the receiver portion of the firearm, thereby supplying any attached accessory devices with power. 
     Once attached power from the power supply  24  travels to the accessory devices via electrical shoe contacts  57  located on mounting shoe  53 , which in turn transmit power through power module contacts  58  on mounting foot  59  of rail grabber  61  and to circuit board  50 . The circuit board  50  contains four longitudinally-extending conductors  38  (shown in broken lines) which are sandwiched between non-conductive layers and have exposed contact pads  64  and  66 . In the depicted embodiment the two exterior conductors may be power contact pads  64  and the two interior conductors may be signal contact pads  66 . Each power contact pad  64  and each signal contact pad  66  connects to one via on the top of transfer contact block  44 . The vias extend through to the bottom of transfer contact block  44  and connect to the corresponding contact pads  68  of flex circuit  40 , which contains corresponding conductors thereon. Flex circuit  40  then transfers the power and signals to and from the other circuit boards  50  via like contact blocks  44 . 
       FIGS. 11 and 12  show the attachment of handgrip unit  22  to the modular rails  30  located on bottom rail chassis  60 . Once handgrip unit  22  attaches to modular rails  30  the handgrip contacts  62  engage the power contact pads  64  on the circuit board  50  enables power to reach handgrip  22 . Likewise, signal terminals on the handgrip unit  22  may contact signal pads  66  on the circuit board  50  to allow signals to travel from handgrip  22  to the accessory device it is controlling.  FIG. 12  also shows an alternate view of the power transfer module  56  and its contacts  58 . 
     Referring now to  FIGS. 13   a  and  13   b , there is shown a signal adaptor  74  which enables off the shelf devices which lack the circuit board  50  attachment means to be used in conjunction with floating rail system  10 . Signal adaptor  74  attaches to modular rails  30  and engages the signal contact pads  66  on circuit board  50  enabling signals to reach the off the shelf laser sight  14   a  via attachment of a plug  78  to signal input  80 . In the depicted embodiment signal adaptor  74  is of a rigid form and easily connects to laser sight  14   a , if signal input  80  is located in a different position on the laser sight  14   a , then signal adaptor  74  may be made of a flexible wire allowing the operator to attach the laser sight  14   a . Once laser sight  14   a  is attached to the Picatinny rails  30  signals may be transferred between the laser sight  14   a  and other devices, such as handgrip unit  22 , allowing for handgrip unit  22  to control accessory device  76 . Additional controllable accessory devices include laser designators, flash lights, communication devices, optical scopes, fire control systems, and other weapon mounted accessories. Any off the shelf accessory devices may be attached to the signal contact pads  66  of floating rail system  10  using signal adaptor  74 . 
     The invention has been described with reference to the preferred embodiments. Modifications and alterations will occur to others upon a reading and understanding of the preceding disclosure herein, whereby it is to be distinctly understood that the foregoing descriptive matter is to be interpreted merely as illustrative of the invention and not as a limitation.