Abstract:
A device is provided for winding wire into a coil. The device includes a shaft for turning on an axis; a hub attached to the shaft; inner and outer wheels; a mandrel having an outer radial surface for looping the wire; and a guide connectable to the mandrel and extending past the inner wheel. The shaft is structurally supported by a housing. The inner wheel, mandrel and outer wheel are removably fastened to the hub, the wire passes along the guide and lays along the radial surface of the mandrel, and the shaft rotates for looping the wire around the mandrel. The shaft can be rotated either manually or by a motor. A system is provided that includes the winding device, and further includes a wire-feed device, particularly for arranging several strands of wire into a ribbon.

Description:
STATEMENT OF GOVERNMENT INTEREST 
       [0001]    The invention described was made in the performance of official duties by one or more employees of the Department of the Navy, and thus, the invention herein may be manufactured, used or licensed by or for the Government of the United States of America for governmental purposes without the payment of any royalties thereon or therefor. 
     
    
     BACKGROUND 
       [0002]    The invention relates generally to wire winding devices. In particular, the invention provides an apparatus for winding wire having a square or rectangular cross-section. 
         [0003]    Efforts to incorporate instrumentation in gun-launched projectiles are adversely affected by damage to sensitive electronics from propellant-induced sudden acceleration. To mitigate this condition, development has been initiated of launchers having more gradual acceleration by using electromagnetic induction-motors, such as for example in U.S. Pat. No. 7,444,919 (under Navy Case 97941). To maximize magnetic field density, coated copper wire that incorporates rectangular cross-sections have been investigated to flow electric current there-through to induce the Lorentz-force motive fields. 
       SUMMARY 
       [0004]    Conventional wire winding apparatuses yield disadvantages addressed by various exemplary embodiments of the present invention. In particular, conventional wire winding devices are limited to round wire due to twist from spooling torsion. Various exemplary embodiments provide a device for winding wire into a coil. The device includes a shaft for turning on an axis; a hub attached to the shaft; inner and outer wheels; a mandrel having an outer radial surface for looping the wire; and a guide connectable to the mandrel and extending past the inner wheel. The shaft is structurally supported by a housing. 
         [0005]    The inner wheel, mandrel and outer wheel are removably fastened to the hub, the wire passes along the guide and lays along the radial surface of the mandrel, and the shaft rotates for looping the wire around the mandrel. The shaft can be rotated either manually or by a motor. Other various embodiments provide a system that includes the winding device, and further includes a wire-feed device, particularly for arranging several strands of wire into a ribbon. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0006]    These and various other features and aspects of various exemplary embodiments will be readily understood with reference to the following detailed description taken in conjunction with the accompanying drawings, in which like or similar numbers are used throughout, and in which: 
           [0007]      FIG. 1  is a perspective view of a wire winding system; 
           [0008]      FIGS. 2A and 2B  are isometric assembly views of a wire feeding device; 
           [0009]      FIG. 3  is an isometric exploded view of a wire winding device; 
           [0010]      FIG. 4  is an isometric assembly view of the wire winding device; 
           [0011]      FIGS. 5 and 6  are isometric detail views of the wire winding device; 
           [0012]      FIG. 7  is a plan view of the wire winding device as observed looking aft; 
           [0013]      FIG. 8  is an isometric detail view of the wire winding device; 
           [0014]      FIG. 9  are isometric disassembly detail view of the wire winding device; and 
           [0015]      FIG. 10  is a plan perspective view of a wound wire. 
       
    
    
     DETAILED DESCRIPTION 
       [0016]    In the following detailed description of exemplary embodiments of the invention, reference is made to the accompanying drawings that form a part hereof, and in which is shown by way of illustration specific exemplary embodiments in which the invention may be practiced. These embodiments are described in sufficient detail to enable those skilled in the art to practice the invention. Other embodiments may be utilized, and logical, mechanical, and other changes may be made without departing from the spirit or scope of the present invention. The following detailed description is, therefore, not to be taken in a limiting sense, and the scope of the present invention is defined only by the appended claims. 
         [0017]    Winding wire around a cylindrical mandrel induces twist as the wire is wound in circular or helical fashion. Typical wire having a circular cross-section readily conforms to such twisting, as such configurations maintain symmetry irrespective of angular orientation. By contrast, rectangular- or square-cross-section wire possesses quadrilateral symmetry, rather than axial symmetry. 
         [0018]    Thus, such twisting disturbs uninterrupted layup of wire having rectangular cross-section, thereby inducing voids and non-homogeneous distribution of the conductive material. To mitigate this condition, various exemplary embodiments provide a wire winder system that addresses the peculiarities of winding rectangular cross-section wire. 
         [0019]      FIG. 1  shows a perspective view  100  of a wire-feed and winding system. A feed spool  110  is suspended on a rack to provide copper wire having a rectangular or square cross-section. The wire inserts into a wire-feed device  120  for direction to a wire winding device  130 , both supported by a platform, such as a table. Interchangeable components include mandrels  140  around which the wire can be wound for application, and pinwheels  150  to secure the mandrel  140  in the winder  130 . 
         [0020]      FIG. 2A  shows a first isometric view  200  of the wire-feed device, also called a feeder and shown within a dash oval as the feed assembly  120  illustrated facing partially forward. A pair of tension plates on the starboard-side  210  and port-side  215  are disposed parallel to each other separated by a distance and joined to each other by four plate separator shafts  220 . Between the plates  210  and  215 , a pair of spool shafts  225  each suspend an in-feed alignment spool  230  and an out-feed tensioning spool  235  at respective the distal and proximal ends of the feed assembly  120 . A pair of friction rollers  240  below the spools  230  and  235  (i.e., upstream and downstream of the source spool  110 ) are also suspended from friction roller shafts  245  between the plates  210  and  215 . 
         [0021]      FIG. 2B  shows a second isometric view  250  of the wire-feed device  120 , also facing partially forward. The spool shafts  225  are laterally secured to the plates  215  and  220  by a set of four bearings  255 . An overrun adjustable friction clutch  260  attaches to that spool shaft  225  for the out-feed spool  235 . A clutch torsion bracket  265  extends beyond the starboard-side plate  210 . At least one strand of wire from the source spool  110  can be disposed to roll along the in-feed spool  230  towards the out-feed spool  235  along a feed direction  270 . The wire then proceeds to the winding device  130 . 
         [0022]    Several wire strands from multiple feed spools  110  can be concatenated together in a linearly disposed ribbon. In the configuration shown, the in-feed spool  230  includes six grooves  280  to lead the wires along the direction  270  towards the out-feed spool  235  with a single wide groove  285  for submitting the ribbon to the winding device  130 . 
         [0023]      FIG. 3  shows an isometric exploded view  300  of a wire winding device  130 , also called a winder, shown as a set of component winder parts  310  that receives the wire from the feeder  110 . The parts  310  are identified as follows: An outer pinwheel  320  is disposed at the proximal end, behind which is a coil mandrel  330 , which are interchangeable with components in the system view  100  labeled by the mandrel  140 , whose diameter depends on the wire assembly desired. 
         [0024]    Additional components associated with the mandrel  330  include a wire finish clamp base  332 , a wire finish clamp  334  and an in-feed wire guide  336 . Screws or alternate fasteners may be used to secure the wire guide  336  to the mandrel  330  for looping the wire. 
         [0025]    Upon completion of the winding process, screws may be used to secure the base  332  to the mandrel  330  and then screws may be used to secure the clamp  334  to the base  332  for maintaining the wire arrangement on the mandrel  330 . Alternatively, other types of fasteners may be used to secure the base  332  and the clamp  334 . An inner pinwheel  340  is disposed behind the mandrel  330 , which can be identical in size and shape to the outer pinwheel  320 . The pinwheels  320  and  330  are shown as interchangeable components in the system view  100  labeled by pinwheel  150 . A plate attachment hub  345  is disposed behind the inner pinwheel  340 . 
         [0026]    The mandrel  330 , pinwheels  320  and  340 , and the hub  345  rotate along a main drive shaft  350  suspended on a first axel bearing  355 . The shaft  350  can optionally be turned by a crank wheel  360 . The example illustrated represents a configuration for hand-power, but artisans of ordinary skill will recognize that alternate modes for providing necessary torque can be availed without exceeding the scope of the invention. 
         [0027]    The crank wheel  360  resides within a frame that includes fore and aft torsion plates  362  and  364  separated by port and starboard support plates  366  and  368 . Suspending from a second bearing  355 , the shaft  350  extends beyond the aft plate  364  to an overrun friction clutch  370  to prevent backlash and coupled to a reduction coupler  375 . A clutch torsion bracket  380  provides an attachment to the aft plate  364  fora worm gear  390  that connects to the shaft  350  and is powered by a drive motor  395 . 
         [0028]    The worm gear  390  enables rotation in one direction to maintain tension in the wire during winding. The drive motor  395  provides motive torque for turning the shaft  350 , as an automatically driven alternative to manually operating the crank wheel  360 . Artisans of ordinary skill will recognize that either the crank wheel  360  or the gear  390  with motor  395 , or else both mechanisms can be employed for the winder  130  without departing from the spirit of the invention. 
         [0029]      FIG. 4  shows an isometric assembly view  400  of the wire winding device  130 , as an assembly. The components  310  are shown with the shaft  350  extending beyond an assembled frame  410  with the crank wheel  360  within. A gear drive sub-assembly  420  attaches to the shaft  350  at the distal end, whereas a wire coiling sub-assembly  430  attaches to the shaft  350  at the proximal end. Select components  310  are identified that correspond to their respective sub-assemblies. The shaft  350 , the pinwheels  320  and  340  and the mandrel  330  rotate counterclockwise  440  as facing the proximate end. 
         [0030]    Each of the pinwheels  320  and  340  include radial slots  450  through which wire can be guided and pass through. In the example shown, each pinwheel  320  and  340  includes eight slots  450  angularly separated by forty-five degrees (45°) or π/4 radians. Those of ordinary skill will recognize that the number of slots  450  can be altered to facilitate application of liquid adhesive along each layer of wire. Furthermore, although single quantities of the base  332 , clamp  334  and guide  336  are illustrated, additional sets of these items can be provided for separate mandrels  330  with which to spool additional wire. Moreover, any slot  450  may be used in this process without departing from the spirit of the invention. 
         [0031]    Wire from the source spool  110  passes through the feed device  120  to the hub  345  for a few turns. An operator directs the wire over the wire guide  336  attached to the mandrel  330  and passing through the inner pinwheel  340  at one of the slots  450 . The wire passes through that slot  450  to lay along the outer radial surface of the mandrel  330 . For a single strand, the wire can wind to lay adjacent a previously wound loop on the mandrel  330 . For multiple strands, the wires can wind to lay flat upon the mandrel  330  as a ribbon. 
         [0032]    Upon completion of a layer of wire loops, the operator can apply adhesive to the wires to sure their arrangement after winding is complete. This process may be repeated until the final layer has been laid on the mandrel  330 . After completion of laying wire on the mandrel  330 , the base  332  and clamp  334  may be secured to the mandrel  330  to prevent axial slippage of the wire. Subsequently, the subassembly  430  may be disassembled and the mandrel  330  removed for the adhesive to cure. After the adhesive has hardened, the wire coil may be removed from the mandrel  330  for its destined application and the mandrel reused for an additional coil. 
         [0033]      FIGS. 5 and 6  show first and second isometric detail views  500  and  600 , respectively, in which the wire guide  336  is disposed forward from the mandrel  330  through the inner pinwheel  340 .  FIG. 7  shows an elevation view  700  from the proximal end of the wire coiling sub-assembly  430 . The flywheel  320  and crank wheel  360  are shown to be aligned together on the shaft  350  and rotating counterclockwise  440 , and the angular distribution of the slots  450  as described can be verified from its initial isometric view  400 . 
         [0034]      FIG. 8  shows a third isometric detail view  800 , while  FIG. 9  shows an isometric detail disassembly view  900 , both of the wire coiling sub-assembly  440 . The wire guide  332  and accompanying finishing clamp  334  are disposed between the mandrel  330  and the outer pinwheel  320 . 
         [0035]      FIG. 10  shows a perspective view  1000  of a wire  1010  after winding and removal from the mandrel  330 . The wire  1010  initially feeds to be wound around the hub  345  at loops  1020  to be directed at extension  1030  around the guide  336  and secured by clamp components  332 ,  334  to form a wire winding coil  1040 . 
         [0036]    Conventional methods of winding these coils employed an unrefined impromptu device, without the capability to hold the arranged loop to close tolerance. Also the conventional device had only the capability to wind a single coil per day, and lacked tensioning abilities for maintaining the coils of wire tight around its core. 
         [0037]    Common methods for making coils in an industrial application include automated machinery. Such conventional machinery typically uses a coated wire with round cross-section for making the coils. High current density applications require coils of rectangular cross-section wire incompatible with commercially available equipment. 
         [0038]    Various exemplary embodiments enable an operator to expeditiously wind several inductive coils in a short period of time while maintaining close geometric tolerances on a consistent basis. In addition, various exemplary embodiments enable a rectangular or square wire to be wound into coils. Such cross-section creates complexity in the coil fabrication process so the embodied device is capable of manipulating the special wires. 
         [0039]    The process for winding wires can be identified as follows: 
         [0040]    Feed at least one wire into the in-feed alignment spool  230  and then through the out-feed tensioning spool  235 ; 
         [0041]    Then pull the wire onto and past the winder  130  to create leader for subsequent application of the coil; 
         [0042]    Take the end of the wire and wrap the wire around the guide  336 ; 
         [0043]    Wrap the rest of the wire around the drive hub  345  by rotating the drive assembly  360  or  430 ; 
         [0044]    Feed the wire onto the mandrel  330  in between the pinwheel plates  320  and  340 ; 
         [0045]    Wrap the wire and apply glue to eight points at the slots  450  around the coil until reaching the number of coil wraps desired; 
         [0046]    Attach the outer coil wire fastener  1020  to the mandrel  330  and clamp the wire in place while maintaining tension; 
         [0047]    Remove the mandrel  330  from the winder  130  and trim the wire off with some length remaining for later wiring operations; 
         [0048]    Hang the mandrel  330  up to let the glue dry for 24 hours; 
         [0049]    Once the glue is dry, remove the outer coil wire clamp  332 ,  334  and slip off the coil from the mandrel  330 ; and 
         [0050]    Repeat as necessary. 
         [0051]    While certain features of the embodiments of the invention have been illustrated as described herein; many modifications, substitutions, changes and equivalents will now occur to those skilled in the art. It is, therefore, to be understood that the appended claims are intended to cover all such modifications and changes as fall within the true spirit of the embodiments.