Flat cable conductor separating apparatus

A cable separator including a pair of slotted rolls that define uniformly spaced apart slitting or shearing sites which are spaced from one another by a distance corresponding to the conductor spacing of a flat cable. A guiding structure at the inlet of the slitting sites for guiding the flat cable thereinto at a proper transverse position to assure that slitting takes place between adjacent conductors. The guiding structure has a plurality of longitudinally extending spring loaded ribs that are spaced from one another by an integral multiple of the interconductor spacing of the cable. A pivotal clamping frame mounted at the inlet of the guiding structure and a mechanism for adjusting the clamping frame to adjust the distance over which the cable conductors are separated by the apparatus.

BACKGROUND OF THE INVENTION 
1. Field of the Invention 
This invention relates to apparatus for separating the conductors of a flat 
cable of the type widely used in computer and like electronic 
environments, such separation being necessary before the insulation on the 
conductors is stripped and the conductors are terminated. 
2. Description of the Prior Art 
In manufacturing flat multiconductor cables, the uniformity of 
interconductor spacing is typically excellent but the width of insulation 
at the lateral edges of the cable can and does vary. Accordingly, many 
prior art conductor separating devices which rely for alignment on the 
side edges of the cable produce unsatisfactory results such as damaging 
the insulation surrounding each conductor. An example of such device is 
shown in U.S. Pat. No. 3,575,329 which discloses two rollers adapted to 
shear the web of insulation between adjacent conductors and an input 
platform having guide rails for engaging the lateral edges of the flat 
cable. As previously indicated, imprecision in the straightness and 
uniformity of the side edges causes misalignment between the rollers and 
the conductors, which produces unsatisfactory conductor separation. 
A separating device disclosed in U.S. Pat. No. 4,046,045 discloses similar 
cable guides or stops in conjunction with a device having reciprocating 
insulation slitters. 
U.S. Pat. Nos. 3,782,227 and 3,817,127 disclose motor driven conductor 
separators where the flat cable must be positioned manually for proper 
alignment with the shearing elements in the machine. The accuracy of 
conductor separation achievable with such machines is dependent upon the 
care exercised by the operator which does not assure reliability in all 
circumstances. 
U.S. Pat. No. 3,677,116 discloses a conductor separator for flat cables 
wherein positioning of the conductors with respect to a shear element is 
achieved by lateral stepped movement of the flat cables by a toothed 
mechanism. Although apparently satisfactory for its intended purpose, the 
patented device is slower than devices employing a longitudinal feed. 
SUMMARY OF THE INVENTION 
A cable separator embodying the present invention includes a pair of 
slotted rolls which define a plurality of uniformly spaced slitting or 
shearing sites which are spaced from one another by a distance 
corresponding to the conductor spacing of the cable, typically 0.050 
inches. In longitudinal alignment with the sites there are upper and lower 
spring loaded members which define longitudinally extending ribs that are 
aligned with the slitting sites and that are spaced from one another an 
integral multiple of the interconductor spacing. The distal edges of the 
ribs are configured so that as flat cable is fed through the spaces 
between the ribbed members, the ribs tend to move the cable laterally as 
the ribs enter the slots or depressions between the cables. Thus when the 
cable reaches the slitting sites, it is aligned so that slitting takes 
place at the webs between adjacent conductors and not at insulation 
surrounding the conductors. 
An object of the invention is to provide an efficient, quickacting 
conductor separator which can produce accurate results without significant 
operator attention. This object is achieved because the above noted ribbed 
members, which define an inlet path to the slitting sites, are spring 
loaded so as to permit the flat cable to be manually moved therethrough so 
as to achieve proper alignment without respect to any side edge guide. 
Another object of the invention is to provide a conductor separating device 
wherein the longitudinal extent of separation can be precisely and 
conveniently controlled. For accomplishing such object, the present 
invention provides at the inlet of the above mentioned ribbed members a 
pivotable clamping frame that has a guide slot aligned with the path 
formed between the ribbed members. The cable is fed through the slot and 
through the ribbed members to the slitting sites. The cable is clamped at 
the slot, and the amount of pivotal movement of the frame is adjustably 
variable to control the distance that the cable is permitted to move 
through the slitting sites. Also the present invention provides a 
calibrated output cable which has suitable graduation to inform the 
operator how far the cable has moved past the slitting sites. 
A further object of the invention is to effect deformation of alternate 
conductors in opposite directions to facilitate individual handling of the 
conductors after separation. This object is achieved by providing upper 
and lower slitted shear rollers at which the slitting is performed and 
providing alternately spaced stripping fingers for cooperation with the 
rollers downstream of the slitting site so that after separation alternate 
conductors are deformed in opposite directions. 
The foregoing together with other objects, features and advantages will be 
more apparent after referring to the following specification and the 
accompanying drawings.

DESCRIPTION OF THE PREFERRED EMBODIMENT 
Referring more particularly to the drawings, reference numeral 12 indicates 
a base plate to one edge of which is secured a side plate 14. A side plate 
16 is supported rigidly to side plate 14 by means of a pair of lower 
spacers 18 and 20 and a pair of upper spacers 22 and 24. The ends of the 
spacers are tapped to receive mounting screws 26 which fix the ends of the 
spacers to the respective side plates. The side plates are supported in 
parallel spaced apart relation, the space between the inner surfaces of 
the side plates being in excess of the width of flat cable to be processed 
by the device. 
Supported for rotation between side plates 14 and 16 are an upper shear 
roll 28 and a lower shear roll 30. Rigid with an extending axially from 
the shear rolls are shafts to the outer ends of which are respectively 
secured drive gears 32 and 34 which mesh with one another to effect 
simultaneous rotation of the rolls. Meshed with upper drive gear 32 is a 
drive pinion 36 which is carried on a drive shaft 38 that extends parallel 
to the shear rolls between side plates 14 and 16. On the end of drive 
shaft 38 opposite pinion 36 is fixed a crank 40 which has an outward 
extending handle 42. Thus rotation of the crank will effect rotation of 
the upper and lower shear rolls. 
As seen most clearly in FIG. 5, shear rolls 28 and 30 are formed with a 
series of circumferentially extending slots 44 to form between adjacent 
slots a series of circumferentially extending ridges 46. Ridges 46 have a 
thickness, i.e. a dimension axially of the shear rolls, slightly less than 
the widths of slots 44 so that the ridges can enter the slots as seen in 
FIG. 5. A clearance in the range of 0.001 to 0.003 inches having been 
found a satisfactory clearance. The slots and ridges are of uniform 
dimension and spaced at intervals corresponding to interconductor spacing 
of the flat cable, e.g. 0.050 inches. The outer circumferential surfaces 
of the ridges are formed with a concave arcuate depression 48 which has a 
radius of curvature greater than that of the individual conductors so that 
at the opposite extremities of each such concave surface a shear edge 50 
is formed. Additionally, from FIG. 5 it will be noted that the depth of 
slots 44 is substantially greater than the diameter of the conductors and 
the distance of penetration of the ridges 46, thereby avoiding undue 
restrictions as the conductors lie in the slots. In one apparatus designed 
in accordance with the invention, each shear roll has thirty ridges and 
thirty slots so as to accommodate a flat cable having a corresponding 
number of conductors. 
The shear rolls are mounted so as to form a bite 52 therebetween; a 
conductor urged into the bite will be drawn through the rollers in 
response to rotation of the rollers through crank 40. In alignment with 
bite 52 is mounted an input guide structure 56 which forms a path 
indicated at arrow 58 aligned with the bite. Input guide structure 56 is 
supported by an upper cross piece 60 and a lower cross piece 62 which are 
rigidly fixed to side plates 14 and 16. The lower surface of upper cross 
piece 60 and the upper surface of cross piece 62 are formed with holes or 
recesses 64, there being four rectangularly positioned such recesses in 
each of the cross pieces. As can be seen in FIG. 3, the recesses are 
slanted toward the left, as viewed in FIG. 3, that is, slanted in a 
direction opposite the direction of cable feed along path 58 toward bite 
52. An angle of slant for recesses 64 and about 30.degree. from vertical 
has been found satisfactory in one apparatus designed according to the 
invention. 
There are upper and lower guide bodies 66 and 68 mounted between cross 
pieces 60 and 62, the upper surface of guide body 66 and the lower surface 
of guide body 68 having slanted bores 70 which are aligned in both 
position and orientation with recesses 64 in the cross pieces. In each 
pair of aligned bores and recesses is disposed a compression spring 72 
which serves yieldably to urge bodies 66 and 68 toward one another and 
toward path 58. Bodies 66 and 68 are each formed with a pair of 
transversely extending through bores 74; extending through each of the 
through bores 74 is a mounting rod 76. Opposite ends of mounting rods 76 
are fixed to side plates 14 and 16. As can be seen in FIG. 3, the diameter 
of through bores 74 exceeds the outside diameter of mounting rods 76 so as 
to permit guides bodies 66 and 68 to move away from path 58 and against 
the force of compression springs 72. The through bores and the mounting 
rods are dimensioned and positioned to limit the inward movement of guide 
bodies 66 and 68, preferably to a position at which the guide bodies are 
not in contact with one another at path 58. Cross pieces 60 and 62 at the 
extremities thereof remote from the shear rolls are each provided with a 
boss 77; the opposing surfaces of guide bodies 66 and 68 have complemental 
rabbet grooves 77R which cooperate with bosses 77 to retain the bodies in 
place against the force of springs 72. 
The lower surface of guide body 66 and the upper surface of guide body 78 
define a plurality of longitudinally extending ribs 78. See FIG. 4. Ribs 
78 are spaced from one another by an integral multiple of the 
interconductor spacing of the flat cable. In the specific embodiment shown 
in FIG. 4, the spacing between adjacent ribs 78 is twice the spacing 
between conductors in the flat cable. As can be seen, upper and lower 
bodies 66 and 68 are so mounted that ribs 78 thereof are in alignment with 
one another on opposite sides of path 58. Ribs 78 are of generally 
truncated triangular shape and have converging side walls 80 and 82 which 
facilitate movement of the ribs into the slots between adjacent conductors 
of the cable. The sloping side walls terminate at a bearing surface 84 
which preferably has a width substantially equal to the width of the web, 
such width in FIG. 4 being greatly exaggerated and enlarged for clarity. 
The inlet end of bodies 66 and 68, i.e. the end remote from bite 52, are 
radiused as at 86 to facilitate movement of the flat cable along path 58 
between the confronting guide bodies. 
For limiting the amount or distance over which the conductors are separated 
by movement between shear rolls 28 and 30, there is a clamping frame 88 
disposed at the inlet end of alignment device 56. The clamping frame has 
two depending legs 90 and 92 which are pinned at 94 for pivotal movement 
with respect to base 12. The frame also has upstanding projections 96 and 
98 which are formed with aligned transverse bores to support a cam rod 
100. Cam rod 100 can be rotated by a handle 102 which is secured thereto. 
The cam rod is biased to a central position by means of a biasing 
mechanism that includes a cotter pin 104 that extends from the cam rod and 
a tension spring 106 which extends between the free end of the cotter pin 
and a point of attachment 108 to leg 92. In the relaxed condition of cam 
rod 100, a chordally extending flat 110 formed on the surface of the cam 
rod is oriented parallel to path 58. Between projections 96 and 98 
clamping frame 88 defines a surface 112 which, as can be seen most clearly 
in FIG. 3, is positioned below the path. Thus, with cam rod 100 in the 
relaxed position shown in FIG. 3, a flat cable can be fed between flat 110 
and surface 112 to input guide structure 56. However, when the cam rod is 
rotated by applying force on handle 102 against the force of spring 106, 
the flat cable is clamped between flat 110 and surface 112. 
Clamping frame 88 is biased to a vertical position, seen in FIG. 1, by 
means of a tension spring 114, one end of which is pinned to leg 92 of the 
clamping frame and the other end of which is pinned to side plate 14. For 
limiting the degree to which the clamping frame can be pivoted outward, 
i.e. in a counterclockwise direction as viewed in FIG. 3, there is an 
adjustable stop formed by a bar 116 one end of which is pinned at 118 to 
leg 92 of clamp frame 88 and the other end of which defines an elongate 
slot 120. A pin 122 extends into slot 120 and is fixed to the inner 
surface of side plate 14. At the end of bar 116 remote from pin 118 there 
is a threaded bore extending from the end of the bar into slot 120. An 
adjusting screw 124 is threaded into hole 123, adjustment of the screw 
effecting adjustment of the amount that the clamping frame can be pivoted 
outward. 
At the outlet end of shear rolls 28 and 30 are provided an upper stripper 
comb 126 and a lower stripper comb 128. The combs have vertical portions 
defining mounting holes 130 at opposite ends thereof, the mounting holes 
admitting screws 132 which are threaded into the edge faces of side plates 
14 and 16 to retain the combs in place. As can be seen in FIG. 2, each of 
the stripper combs has a row of horizontally extending fingers 134 which 
are sized to enter slots 44 in shear rolls 28 and 30 so as to strip the 
conductors from the slots after the webs that join the conductors have 
been sheared. As can be seen in FIG. 5, alternate conductors enter slots 
in opposite shear rolls so that when the conductors are stripped from 
engagement in the slots, alternate conductors will be deformed upward and 
downward as indicated in FIG. 7. Stripper combs 126 and 128 are mounted so 
that fingers 134 are disposed approximately 30.degree. from the shear site 
between the rollers, i.e. from the point of tangency between the rollers. 
This spacing provides optimum deformation of the conductors to facilitate 
subsequent access to individual conductors. 
At the outlet end of the apparatus is supported an outlet table 136. The 
table is mounted to side plates 14 and 16 in a horizontal position below 
the path of movement as the separated conductors exit the shear site 
formed by shear rolls 28 and 30. As can be seen in FIG. 1, the upper 
surface of table 136 is provided with graduations 138 which are typically 
arranged in inches and fractions of inches to provide a visual indication 
of the distance over which the conductors of a cable transported through 
the shear site are separated. 
Before operation of the apparatus is summarized, reference is made to the 
fragment of flat cable shown in cross section in FIG. 4. The flat cable 
includes a plurality of wire conductors C each of which is jacketed by an 
insulative body B of generally cylindrical shape. Extending between 
adjacent bodies B are insulative webs W which can be integral with bodies 
B or adhered thereto. Webs W retain the conductors in a flat array and in 
uniformly spaced relation. 
The operation of the embodiment shown in the drawings will now be 
described. With the parts of the apparatus positioned as shown in FIG. 1, 
a length of flat cable, the individual conductors of which are to be 
separated, is moved along path 58 between cam rod 100 and surface 112. 
Referring to FIG. 3, the end of the flat cable can be moved between ribbed 
bodies 66 and 68 because of the presence of radiused surface portions 86. 
Because the ribbed bodies 66 and 68 are yieldably supported by virtue of 
compression springs 72, the cable can be moved through input guide 
structure 56 with but little resistance. As the cable traverses ribs 78 in 
the input guide structure, the resilient force imposed by spring 72 will 
urge the ribs into the slots between adjacent conductors, thereby 
effecting slight lateral movement of the cable until rib surfaces 78 
contact webs W and webs W are aligned with the shear sites formed by shear 
rolls 28 and 30. Additionally, bodies 66 and 68 as well as ribs 78 formed 
on the surfaces thereof have sufficient longitudinal extent that the flat 
cable will be longitudinally aligned straight into the shear sites when 
the ribs are in contact with webs W. Such manual insertion of the cable 
continues until the end of the cable encounters bite 52. Next crank 40 is 
rotated in a clockwise direction as viewed in FIG. 1 so as to draw the 
cable into the shear sites formed by the shear rolls. Because the 
conductors have been properly aligned by movement through input guide 
structure 56, each individual conductor will enter a concavity 48 on 
ridges 46 of the shear rolls. Further rotation causes the ridges to enter 
slots 44 where shearing of the web occurs. Still further rotation brings 
the conductors into contact with teeth 134 of stripping combs 126 and 128 
for delivery onto table 136. Rotation can continue until the ends of the 
conductors register with an appropriate graduation 138 on the surface of 
the table. Thereafter the rotation of crank 40 is terminated and the 
separated cable can be withdrawn by pulling it in the opposite direction. 
In those instances where the conductors in a large number of cables are to 
be separated for a uniform length, clamping frame 88 can be used to 
advantage. First, after the desired amount of separation is determined, 
screw 124 is adjusted so that the outward most position of the clamping 
frame, i.e. the position shown in FIG. 3, establishes the distance that 
the frame will move from the fully outward position to a vertical position 
as shown in FIG. 1. After the arc through which the clamping frame can be 
moved is thus established, the cable is moved through the space between 
cam rod 100 and surface 112, through input guide structure 56 and into 
contact with bite 52. The cable is there manually retained while clamping 
frame is pivoted away from the main frame of the structure, such pivotal 
movement terminating when screw 124 contacts pin 122 in slot 120. In such 
position of the clamping frame 88 handle 102 is rotated so that the edges 
of flat 110 clamp the cable against surface 112. Next handle 40 is rotated 
to move the cable through the shear sites between rolls 28 and 30, thus 
pivoting the clamping frame toward a vertical position. When the vertical 
position of the clamping frame is reached, further movement of the cable 
is prevented and force on crank 40 is then terminated. Handle 102 is 
released to permit spring 106 to restore cam rod 100 to a released 
position shown in FIG. 3 and the cable can be manually withdrawn. 
Thus it will be seen that the present invention provides a conductor 
separating apparatus for flat cables which is highly accurate in that it 
effects precise transverse alignment of the cable conductors before they 
reach the shear site. Apparatus embodying the invention can be used very 
rapidly because the alignment provided by input guide structure 56 is 
accomplished without effort by or attention of the operator. Accurate 
separation of the cable is achieved even if the lateral edges of the flat 
cable are irregular or nonuniform because the side edges are not used for 
aligning the cable. 
Although one embodiment of the invention has been shown and described it 
will be obvious that other adaptations and modifications can be made 
without departing from the true spirit and scope of the invention.