Apparatus for forming electrical coil assemblies

Apparatus, for winding coils of various geometric configuration, includes a rotary spindle provided with a mounting face on which a segmented core spool assembly is mounted. This assembly is thus fixed by a clamping flange extending a tongue into the spindle. A cam and a swash plate on the spindle then articulate a pivoted arm on which a wire guide is fixed. The cam is then useful in minimizing the dynamic components of the wire wound onto an irregular shape while the swash plate controls the winding lace.

BACKGROUND OF THE INVENTION 
1. Field of the Invention 
The present invention relates to the method and apparatus for winding coils 
and more particularly to a method and structure for forming geometrically 
varied coil assemblies. 
2. Description of the Prior Art 
In my prior U.S. Pat. No. 4,809,578 I have described an acoustic pickup 
assembly which, amongst its other features, includes an elongate 
electrical winding. This winding, and other windings of complex geometric 
form, present some difficulty in assembly. 
In a typical prior art setting, coils are often wound in automated 
processes, particularly when dimensional limits and miniaturization are 
contemplated. Simply, coil windings often entail very thin wire sizes, 
small winding dimensions and the consequent limits on winding tension and 
wrapping that these present. These precise limits and physical constraints 
are often beyond the limits of manual facility and thus are, of necessity, 
automated. Accordingly, various automatic winding assemblies have been 
devised in the past which accommodate these limitations without the 
necessity of manual control. 
These automated winding schemes, however, contain plate regular bobbins or 
shapes for the coil assembly. Irregular shapes, in distinction, present 
various wire force transients in the course of rotary winding. Thus, the 
convenience of automatic coil assembly available for regular shapes is not 
effective for novel geometries. 
I have found that various novel results are obtainable from irregular coil 
geometries. For example, the core pieces of the coil may be set in 
isolation and thus become useful as the electrical terminals. Thus, by 
segmenting and isolating core pieces plural windings may be achieved which 
separately or in combination produce the desired results. These and other 
results are obtainable in a geometry which is concurrently useful in 
winding and it is one example thereof that I now set out. 
SUMMARY OF THE INVENTION 
Accordingly, it is the general object and purpose of the present invention 
to provide a novel winding arrangement for geometrically irregular 
electrical coils. 
Other objects of the invention are to provide a coil assembly useful in 
defining a plurality of overlaid windings. 
Yet further objects of the invention are to provide a coil winding method 
of universal application. 
Briefly, these and other objects are accomplished within the present 
invention by conforming a core piece for an elongate coil by way of a 
plurality of channel segments of integer segment dimension, such that one 
channel segment is coterminous with one or more other channel segments 
laid along side thereof. Preferrably, the channel members each include 
perforations in the respective spines thereof, such perforations being 
spaced in equal intervals along the channel length. A plurality of 
insulative spacers is then provided with conforming posts engaged in the 
perforations. Thus the insulators interlock the segments into a single 
integral assembly. In this form the core assembly may be mounted onto the 
winding post of a rotary fixture by way of a retainer extending a tongue 
through the gap between adjacent spacers. This tongue is then secured in 
the fixture compressing the core assembly therebetween. 
It will be noted that the resulting core assembly is generally elongate in 
shape. When rotated along with the fixture the ends of the core assembly 
describe a varying linear rate relative any wire guide. This varying 
velocity, in turn, results in a varying kinematic effect (acceleration) 
which varies the winding tension on the core assembly. To reduce this 
kinematic variable a wrapping guide is positioned just outside the arc of 
the core assembly and geared to move transversely across the core at a 
selected multiple of the core rotation. Thus, only a short length of the 
wire strand is in free response, limiting the mass contribution on the 
wire tension. 
Each core segment comprising the core assembly may be coated with an 
insulative coating on its interior and may be plated, coated, or otherwise 
prepared at the ends for electrical contact. Thus, the ends of each 
segment may be formed as a tooth-like projection around which the wound 
wire is terminated or wrapped. 
In this manner convenient termination of each winding may be easily 
achieved in an assembly which is conformed for automated winding. 
Of course, various tensioning mechanisms may be employed in the course of 
winding including spring-tensioned pulleys and friction devices along the 
wire path. These then may be adjusted in tension and may be geared with 
the tongue direction of the retainer for a modulated tension profile.

DESCRIPTION OF THE PREFERRED EMBODIMENT 
As shown in FIGS. 1-3 the inventive winding assembly, generally designated 
by the numeral 10, comprises a rotary mount 11 provided with a circular 
mounting boss 12 fixed adjacent a bilobed cam 14 on a spindle 15. A 
rectangular pocket 16 extends from the exposed face of the boss 12 through 
the cam 14 and into the interior spindle 15. This rectangular pocket 16 is 
conformed to receive an elongate, rectangularly, sectioned tongue 18 
extending from the flange 19 at one end thereof. The other face of the 
flange 19 may be shaped to include a conical tie down 20 to which one end 
of a wire W may be affixed. 
Spindle 15 is then driven in rotation, across a gear train 25, by an 
electrical motor 26. As thus rotated, spindle 15 also advances in rotation 
cam 14 against a roller 31 at the free end of a spring loaded arm 32. A 
jeweled guide 33 at the end of this arm then translates the turning angle 
of the wire W to move with the motion of the roller. 
In this form the winding assembly 10 is useful in receiving an elongate 
core assembly generally shown at 50, and comprising a first elongate 
channel segment 51 adjacent to a second and third segment 52 and 53. 
Preferrably each of the segments is generally of a C-shaped section with 
the spines perforated at even increments with paired holes 55. A plurality 
of rectangular insulative separators 56 is then placed between the spines 
of segment 51 and segments 52 and 53, each separator being provided with 
posts 57 conformed for indexed receipt in holes 55. 
Segments 52 and 53 may be of a length of integer division of the length of 
segment 51. Thus, the combination of segments 51, 52 and 53 and the 
separators 56 cooperate to form an integral core or spool assembly around 
which the wire W is to be wound. This is effected by insertion of the 
tongue 18 into the common interspace between the segments to compress the 
assembly by the opposition of the flange 19 and the face of the boss 12. 
Once thus compressed a set screw 39 extending into spindle 15 fixes the 
tongue 18 in position. 
One should note that in this arrangement the lobes 14L of the cam 14 may be 
shaped and aligned to lead the advancement of the ends of the core 
assembly 50. The cam shaping and lead may be selected to minimize the 
dynamic loading of the wire W as it is laid up into the combined interior 
of segments 51, 52 and 53. This dynamic loading may be further minimized 
by way of spring loaded take up rollers 61 and 62 in the wire path from a 
spool 63. Moreover, by selecting an arm length for the arm 32 for minimal 
geometric effects a virtually even and consistent wire force can be 
applied insuring an even wrapping onto the core assembly. 
The wrapping lace or pattern may be further controlled by a swash plate 37 
formed around the boss 12 against which a finger 36 from the arm 32 is 
pressed. Thus, arm 32 may be transversely flexed, in the manner of a 
derailleur, along with its pivotal motion on the cam, both to minimize 
wire loading transients and to effect the necessary lacing. 
Each of the segments 51, 52 and 53, moreover, may be insulatively coated on 
their interior, preferrably to a thickness of 0.003 to 0.005 inches, each 
segment including corresponding end fingers 51a, 52a, and 53a around which 
the wire W may be electrically terminated by wrapping or soldering. Thus, 
each segment 51, 52, and 53 also forms an electrical terminal with the 
size convenience for miniaturized implementation. 
In this form one or more windings may be overlaid onto a core spool of a 
varying geometric arrangement where the segments of the core spool also 
provide the electrical terminals for the thin wire (40-53 gauge) wound 
thereon. In each instance the tapered end of the retainer is useful for 
the beginning wire tie down which then can be variously reconnected on 
electrical assembly. 
Segments 51, 52 and 53, moreover, each comprise ferromagnetic material 
structure which is characterized by substantial thermal mass and 
conductivity. Thus, upon completion of a winding the wire filament W 
wrapped onto the termination fingers 51a, 52a and 53a is geometrically 
fixed to a localized path, allowing for soldered termination at which 
sufficient heat is applied to melt and vaporize the thin insulative 
coating normally on the filament. In this manner the core segment 
arrangement and geometry render convenient the winding coils thereabout 
while also providing a convenient soldering terminal for electrical 
connection. 
Obviously many modifications and changes may be made to the foregoing 
description without departing from the spirit of the invention. It is 
therefore intended that the scope of the invention be determined solely on 
the claims appended hereto.