Abstract:
Embodiments of the invention comprise a portable device and a method for rapidly collecting tubing, line, wire, or other long, flexible objects onto a spool. The respooling device comprises a fixed compression nut attached to a threaded rod and an adjustable compression nut removably coupled to the threaded rod. The threaded rod and compression nuts have thread selected for mechanical strength, smooth operation without lubrication, and rapid translation of the adjustable compression nut along the threaded rod. A spool clamped around the threaded rod by the compression nuts is automatically centered on the rotational axis of the respooling device. A driver turns the threaded rod, compression nuts, and spool to wind material onto the spool. Some embodiments respool material at rates greater than 30 feet (9.1 meters) per second. Some embodiments include a cordless driver. Some embodiments include a spool adapted for respooling a particular material, for example shock tube.

Description:
FIELD OF THE INVENTION 
       [0001]    The present invention is generally directed to a portable apparatus for winding flexible material onto a spool. 
       BACKGROUND 
       [0002]    Flexible materials such as rope, wire, or tubing may be wound onto spools for storage or to collect the material for reuse. A spool may comprise a drum or hub having at each end a large square or circular flange. Flexible material wound around the drum is prevented from falling off the ends of the drum by the flanges. The drum may have an axial aperture through which a shaft may be inserted to facilitate rotation of the spool. 
         [0003]    It is not unusual for almost any sort of shaft or bar to be used to support a spool while flexible material is wound onto the spool. For example, objects such as large screwdrivers, lengths of pipe, dowels, tool handles, or rebar may be used to hold a spool. However, a shaft having suitable size to fit a spool may not be available when it is needed, or an object appropriated for use as a shaft may bend or break in use. 
         [0004]    In some situations, it is advantageous to be able to collect a large quantity of flexible material onto a spool as rapidly as possible. Collecting sensor tubing from a roadway upon which traffic is moving is an example. Another example is the collection of wire or tubing used in demolition with explosives. For example, hollow plastic tubing having an inside diameter of about 1 millimeter, an outside diameter of about 3 millimeters, and containing an explosive chemical may be deployed by military personnel in the removal of improvised explosive devices (IEDs). Pieces of such tubing, also known as shock tube, may be joined together with special connectors to create an assembly having a length of a thousand feet or more. After demolition of the IED, remaining shock tube is collected to prevent unauthorized use. It is desirable to pick up any remaining shock as quickly as possible to reduce personnel exposure to hostile activity and hazardous materials in the vicinity. Collecting a thousand feet of shock tube comprising a combination of tubing and inline connectors takes many minutes using means currently available. Personnel must leave the protection offered by armored vehicles to collect the shock tube. Furthermore, unused shock tube must be protected during respooling from ignition sources such as sparks or static discharges. 
         [0005]    Many devices for rotating a spool to collect flexible material are known. However, some devices are too large or bulky to be easily carried by a person or to be used in confined spaces such as the interior of a vehicle or a small construction work site. Other devices are not strong enough for rough service, are not suitable for use in very dusty or muddy environments, or are unable to wind material onto a spool quickly enough to minimize operator exposure to dangerous conditions. 
         [0006]    What is needed is a portable device for rapidly winding flexible material onto a spool. What is further needed is a device able to withstand heavy use with minimum maintenance. A device which permits an operator to collect material from a confined, protected location is also needed. 
       SUMMARY 
       [0007]    Embodiments of the invention comprise a respooling device for rapidly, securely, and removably attaching a spool to a drill, driver, or other motor. Embodiments of the invention enable flexible material to be quickly collected onto the spool by rotating the respooling device and the spool with the drill or driver. A respooling device built in accord with the present invention comprises a fixed compression nut attached to a threaded rod and an adjustable compression nut removably coupled to the threaded rod. The threaded rod and compression nuts have a thread selected for mechanical strength and for rapid advancement of the adjustable compression nut along the threaded rod. The fixed and adjustable compression nuts have conical surfaces to automatically center a spool along the rotational axis of the respooling device. Materials selected for the threaded rod and adjustable compression nut facilitate operation of the device without lubrication from grease or oil. A portion of the threaded rod is shaped for attachment to a collet, clamp, or chuck on the drill or driver, and for rotation by the drill or driver without slippage. The drill or driver may be a device having a rotating output shaft and a controllable rate of shaft rotation, for example an electrically powered corded or cordless driver, a motor, or a manually operated mechanical device. The driver may also be a wrench or other manually operated tool capable of applying torque to a shaft. Some embodiments of the invention include a driver. Some embodiments may include a spool adapted for respooling a particular material, for example shock tube. 
         [0008]    This section summarizes some features of the present embodiment. These and other features, aspects, and advantages of the embodiments of the invention will become better understood with regard to the following description and upon reference to the following drawings, wherein: 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0009]      FIG. 1  is a pictorial view of an embodiment of a respooling device in accord with the invention. 
           [0010]      FIG. 2  is a pictorial view of an example of a threaded rod having a single helical thread with a triangular thread profile, with the thread pitch labeled. 
           [0011]      FIG. 3  is a pictorial view of an example of a threaded rod having five interleaved helical square or trapezoidal threads with the same value of thread pitch as the single helical triangular thread of  FIG. 2 . 
           [0012]      FIG. 4  is a pictorial view of a threaded rod having a threaded portion adapted for rapid advancement of an adjustable compression nut and a polygonal portion adapted for attachment to a driver. 
           [0013]      FIG. 5  is pictorial view of a compression nut showing a conical surface adapted for centering a hub aperture on a spool and a gripping structure adapted for holding and tightening the compression nut by a gloved hand. 
           [0014]      FIG. 6  is a view of a compression nut from a direction opposite that of  FIG. 5 . A compression nut with a set screw installed as in  FIG. 6  is a fixed compression nut. An adjustable compression nut may omit the set screw. 
           [0015]      FIG. 7  is a pictorial view of the respooling device of  FIG. 1  mounted in an adjustable chuck on a driver. An alternative embodiment further comprising a driver is marked in the figure. 
           [0016]      FIG. 8  is a pictorial view of an example of a spool. 
           [0017]      FIG. 9  is a pictorial view of an embodiment showing a spool in place on the respooling device. An alternative embodiment further comprising a driver or a spool or a combination of both is marked in the figure. 
       
    
    
     DESCRIPTION 
       [0018]    Embodiments of the invention comprise a respooling device for rapidly and firmly attaching a spool to a driver, thereby enabling spooling of a large quantity of flexible material in a short period of time. Embodiments may be used for rapid spooling of flexible materials. As used herein, flexible material refers to, but is not limited to, light chain, cord, rope, wire, cable, optical fiber, ribbon, tubing, hose, or similar materials or objects able to be wrapped around a spool. Some embodiments further comprise a driver. As used herein, a driver refers to a mechanically operated drill, a ratcheting wrench or similar manually-operated tool capable of rapidly and repeatedly applying torque to a load, a corded electric drill or driver, a cordless (i.e., battery-powered) electric drill or driver, or a motor with an output shaft having a controllable rate of rotation, for example an electric motor or a power take-off shaft on a construction or agricultural vehicle. Embodiments of the invention operate without the need for greasy or oily lubricants and are therefore well suited for use in dusty or muddy environments. Embodiments of the invention are particularly well suited for use in confined spaces and in situations where a person operating the respooling device desires to minimize exposure to hazardous or unpleasant factors in the vicinity. 
         [0019]    A respooling device in accord with an embodiment of the invention is illustrated in  FIG. 1 . The respooling device  100  of  FIG. 1  comprises a threaded rod  102 , an adjustable compression nut  104  removably assembled to the threaded rod  102 , and a fixed compression nut  106  firmly attached to the threaded rod  102 . The threaded rod  102 , shown in more detail in  FIG. 4 , is formed with a threaded portion  402  and a polygonal portion  404 . The flat faces of the polygonal portion  404  reduce undesirable slippage of the threaded rod  102  in a chuck, clamp, or collet of a driver. As an example, in one embodiment the polygonal portion  404  is hexagonal, has a length dimension of 1.2 inches (3.0 centimeters), a dimension across the flats of 0.375 inch (0.953 centimeters), and an overall length including the threaded portion  402  and the polygonal portion  404  of 12.0 inches (30.5 centimeters). 
         [0020]    The threaded rod  102  may alternately be formed with a square or a trapezoidal thread. The thread may optionally be a multi-start thread. For comparison purposes, an example of a single-start triangular thread is shown in  FIG. 2 . In  FIG. 2 , a single thread  202  wraps in a helix around the core of a threaded rod. A single thread has the cross-sectional shape of a triangle and the spaces between threads are triangular, although the apex of the thread and the bottom of the space between threads may have a small flat or break. A separation between two adjacent coils of the thread helix is known as the thread pitch and is marked with the letter “A” in  FIG. 2 . Threaded fasteners routinely encountered on a daily basis generally have threads similar to those shown in  FIG. 2 . 
         [0021]    In comparison to the single-start triangular thread of  FIG. 2 ,  FIG. 3  represents a multi-start square or alternately a multi-start trapezoidal thread. In a multi-start thread, more than one helical thread is interleaved along the length of the threaded rod.  FIG. 3  illustrates an example of a 5-start thread, comprising five separate, interleaved thread helices wherein the thread pitch marked “A” is the same pitch as in  FIG. 2 , and the separation of two adjacent coils of the same thread helix is marked “B”. Multi-start threads have the advantage of causing a nut to advance more quickly along the length of the threaded rod compared to a rod with a single-start thread. 
         [0022]    A thread having a square cross section is stronger than a thread having a triangular cross section, but a square cross section is difficult to manufacture. A thread with a trapezoidal cross section is easier to manufacture than a square cross section and stronger than a thread with a triangular cross section. Square threads and trapezoidal threads have flat thread apexes and flat valleys between threads. An example of a trapezoidal thread is known as an Acme thread, which has an angle of 29 degrees between opposing faces on the sides of adjacent threads. In comparison, a corresponding angle for a triangular thread is about 60 degrees. 
         [0023]    In one example, the threaded rod  102  of  FIG. 1  and  FIG. 2  is formed from 4140 steel alloy, has a surface coating to reduce rusting, an outer diameter of 0.5 inch (1.3 centimeter), Acme size 10 threads, and a 5-start thread. Such a thread will cause an adjustable compression nut  104  with corresponding thread to advance along the threaded rod  102  a distance of 1 inch (2.5 centimeters) for every two complete 360° rotations. It will be appreciated that embodiments of the threaded rod  102  and respooling device  100  may comprise other polygonal shapes, other thread sizes, other materials, and other length and diameter dimensions, and that such variations may be used singly or in combination. 
         [0024]    The adjustable compression nut  104  and fixed compression nut  106  of  FIG. 1  are similarly formed. The compression nuts  104  and  106  are preferably formed from a bronze alloy due to the self-lubricating properties of the material. A view toward the conical surface  508  and bearing surface  510  on an adjustable compression nut  104  is shown in  FIG. 5 . A view toward the back face of a fixed compression nut  106  is shown in  FIG. 6 . The difference between the embodiments of  FIG. 5  and  FIG. 6  is the addition of a means or preventing rotation  602  to the fixed compression nut  106  of  FIG. 6 , the means of preventing rotation  602  being used to lock the fixed compression nut  106  against the threaded rod  402 . In one embodiment, the means of preventing rotation  602  is a metal dowel pin having a diameter of 0.125 inch (3.18 millimeters). Other acceptable means of preventing rotation  602  include, but are not limited to, a roll pin, a socket head set screw, adhesive, and a spot weld. The aperture  502  and means of preventing rotation  602  may optionally be replaced with a slot in the threaded aperture  504 , wherein the slot is adapted to hold a Woodruff key or similar shaft locking device. A fixed compression nut  106  having a slot for a Woodruff key is used with a threaded rod  102  similarly modified with a slot to hold a Woodruff key. The fixed compression nut  106  may optionally be attached to the threaded rod  102  by being formed as part of the threaded rod. 
         [0025]    The adjustable compression nut  104  of  FIG. 5  has sufficient mass to enable a significant contribution from momentum to moving the nut along the threaded rod. For example, in one embodiment an adjustable compression nut  104  as in  FIG. 5  and made from an alloy of bronze has a mass of about  130  grams. One will appreciate that alternative embodiments comprise compression nuts having other amounts of mass and made from other materials. Rapid motion of the compression nut along the threaded rod is aided by the mass of the nut. Rapid motion of the compression nut along the threaded rod is a factor in enabling embodiments of the invention to be set up and deployed quickly in the field and is a particular advantage of embodiments of the invention compared to other spooling devices known in the art. 
         [0026]    The adjustable and fixed compression nuts of  FIG. 5  and  FIG. 6  are formed with a gripping structure  506 . The gripping structure  506  has a shape that is adapted for structural strength and for firm gripping by a gloved hand. One will appreciate that alternative embodiments include gripping structures having variations in size and shape. In its simplest form, the gripping structure may be a pair of flat tabs joined to a central cylinder through which the threaded aperture  504  passes, comparable to the wings of a wing nut. 
         [0027]    An embodiment of a respooling device is shown attached to a driver comprising a cordless drill in  FIG. 7 . Some embodiments include the respooling device and the driver. The polygonal portion  404  of the threaded rod in the respooling device  100  is inserted into the adjustable chuck  704  of a driver  702 . The adjustable chuck  702  is tightened to prevent slippage of the respooling device  100  in the chuck. The chuck  704  on the driver  702  may optionally be replaced with a clamp adapted to hold the respooling device  100 . In preparation for attaching a spool, the adjustable compression nut  104  is removed from the respooling device  100  by turning the nut by hand or by holding the nut and then operating the driver  702  in reverse. 
         [0028]    An example of a spool for use with embodiments of the invention is shown in  FIG. 8 . The spool  802  has a hub  902  with an axial hole  904 . Flexible material is wound around the hub  902  and prevented from falling off the spool by the flanges on the ends of the spool. Spools having flanges larger or smaller than those shown in  FIG. 8 , spools with flanges of other shapes, or spools lacking flanges may also be used with or optionally included with embodiments of the invention. Spools adapted for a particular use may be included with an embodiment. For example, some embodiments may include spools of the general shape shown in  FIG. 8  made from electrically nonconducting, nonsparking materials suitable for use with shock tubes. 
         [0029]    A spool  802  is shown in position on an embodiment of the invention in  FIG. 9 . After removing the adjustable compression nut  104  as previously described, the threaded portion  402  of the respooling device&#39;s threaded rod is placed through the axial aperture of the spool&#39;s hub. The spool is positioned against the bearing surface of the fixed compression nut  106  and the adjustable compression screw  104  is threaded onto the end of the rod. The adjustable compression nut  104  is turned, either by hand or by holding the nut and operating the trigger  706  on the driver  702 , until the bearing face of the adjustable compression nut  104  presses firmly against the spool  802 . The adjustable compression nut  104  advances very quickly along the length of the threaded rod because of the multi-start thread on the rod and nut. The opposing conical surfaces of the adjustable compression nut  104  and the fixed compression nut  106  cause the spool  802  to be self-centering along the rotation axis of the driver for spools having an axial aperture with a diameter greater than the apex diameter of the conical surfaces (marked “D 1 ” in  FIG. 5 ) and less than the base diameter of the conical surfaces (marked “D 2 ” in  FIG. 5 ). Spools having an axial aperture diameter greater than dimension D 2  may be used with an embodiment of the invention, but the spool may not self-center between the compression nuts. 
         [0030]    After the spool is attached to the respooling device, flexible material is attached to the spool and the spool is turned by the driver to wind material onto the spool. The material to be wound need not be uniform, for example, the material to be wound may comprise a combination of cable or tubing and in-line connectors. The rate at which material is wound onto the spool may be varied over a range from about an inch per second to approximately 40 feet per second. As an example, an embodiment having a driver comprising a cordless drill collected 1000 feet of shock tube in about 1 minute, corresponding to a respooling rate of about 17 feet (5.1 meters) per second. One will appreciate that a respooling rate depends on factors including, but not limited to, the dimensions and material properties of the material being spooled, the dimensions of the spool, the rotation rate of the driver, an amount of battery charge or other input power available for operating the driver, and an amount of torque available from the driver for turning the spool. Total deployment and respooling time for setting up the respooling device and collecting 1000 feet of shock tube was about 2 minutes, about ten percent of the time needed for collecting a comparable length of shock tube by conventional methods. 
         [0031]    The present disclosure is to be taken as illustrative rather than as limiting the scope, nature, or spirit of the subject matter claimed below. Numerous modifications and variations will become apparent to those skilled in the art after studying the disclosure, including use of equivalent functional and/or structural substitutes for elements described herein, use of equivalent functional couplings for couplings described herein, or use of equivalent functional steps for steps described herein. Such insubstantial variations are to be considered within the scope of what is contemplated here. Moreover, if plural examples are given for specific means, or steps, and extrapolation between or beyond such given examples is obvious in view of the present disclosure, then the disclosure is to be deemed as effectively disclosing and thus covering at least such extrapolations. 
         [0032]    Unless expressly stated otherwise herein, ordinary terms have their corresponding ordinary meanings within the respective contexts of their presentations, and ordinary terms of art have their corresponding regular meanings.