Electrical connector application tool

A tool for terminating an electrical cable by applying to the cable a connector assembly which includes a housing and an insert received in snap-in assembly within the housing. The insert maintains bare end portions of individually insulated conductors which comprise the cable in electrically contacting engagement with spring contacts within the housing and retains the cable in assembled relation to the connector assembly. The tool has an elongated body with wire insulation strippers at opposite ends thereof for preparing an end portion of a cable. A recess in the body intermediate the wire strippers receives a partially assembled connector assembly and facilitates movement of the insert thereof into snap-in engagement with the connector assembly using a screw driver or the like in conjunction with the tool to apply prying force to the partially assembled connector assembly.

BACKGROUND OF THE INVENTION 
This invention relates in general to tools of the type used to terminate 
electrical cables and deals more particularly with an improved portable 
hand tool for applying to a terminal end of an electrical cable a 
connector assembly which includes a housing and an insert assembled in 
snap-in engagement with the housing. The tool of the present invention is 
particularly adapted for applying a modular plug type connector assembly 
to terminate a cable which contains a plurality of individual solid wire 
conductors. Bare end portions of the conductors are rigidly supported in 
slots in a connector assembly insert which is assembled within an 
associated housing. The insert cooperates with the housing to bias the 
bare end portions into electrically contacting engagement with associated 
spring contacts within the housing. Cables terminated in the 
aforedescribed manner are particularly suitable for use in electrical 
distribution systems, in the telecommunication industry, for example. In 
the installation and repair of such distribution systems cable termination 
in the field is required. It is the general aim of the present invention 
to provide an improved durable lightweight portable hand tool for use in 
the field termination of such cable with connector assemblies such as 
aforedescribed. It is a further aim of the invention to provide an 
expendable tool of the aforedescribed general type for low cost 
manufacture. 
SUMMARY OF THE INVENTION 
In accordance with the invention, an improved tool is provided for applying 
to a terminal end of an electrical cable a connector assembly which 
includes a housing and an insert received within the housing. When the 
connector assembly and cable are in a partially assembled condition, the 
insert projects rearwardly from the connector assembly housing. The 
connector assembly includes means for securing the insert within the 
housing in response to movement of the insert further into the housing 
from a partially assembled position. The tool comprises a tool body which 
includes restraining means for receiving a partially assembled connector 
assembly and restraining it for movement in at least a rearward direction 
relative to the tool body. A first abutment surface on the tool body and 
in the part of rearward movement of the connector assembly is engageable 
with a rear wall of the insert. The tool further includes a first fulcrum 
means on the tool body spaced forwardly of the first abutment means a 
distance greater than the overall length of the partially assembled 
connector assembly, as measured from front to rear, for supporting a 
prying element in a first position. The prying element is used in 
conjunction with the tool to apply prying force to move the housing 
rearwardly relative to the tool body whereby to forceably move the insert 
into the housing.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENT 
Turning now to the drawings and referring first particularly to FIGS. 1-7, 
an electrical connector application tool embodying the present invention 
is indicated generally by the reference numeral 10. The tool 10 is 
particularly adapted for applying to an electrical cable an electrical 
connector assembly which includes a housing and an insert which is 
received in snap-in engagement with the housing and which cooperates with 
the housing to retain the electrical cable in attached electrically 
conducting relation to the connector assembly. A typical connector 
assembly, illustrated in FIGS. 8 and 9 and indicated generally by the 
reference numeral 12, is shown connected to the terminal end of an 
electrical cable 14 which may, for example, comprise a circuit 
distribution cable for a telephone system or the like. The illustrated 
connector assembly 12 is an eight position modular plug type connector and 
includes a housing 16 and an insert 18, shown in FIG. 9, which is received 
within a cavity 17 in the housing, as best shown in FIGS. 16 and 17. A 
partially assembled position of the insert 18 relative to the housing 16 
is indicated in broken lines in FIG. 9. 
Referring to FIGS. 8, 9, 16 and 17, the housing 16 is made from a 
dielectric plastic material, is generally rectangular, and as oriented in 
FIGS. 9, 16 and 17 has a vertically disposed front wall 19, a top wall 21, 
a stepped bottom wall which includes a front portion 23 and a rear portion 
25 vertically offset from the front portion, and a pair of substantially 
identical side walls 27, 27. The cavity 17 is defined by the inner 
surfaces of the front, top, bottom and side walls of the housing 16. An 
aperture formed in a central part of the rear portion 25 proximate the 
junction of the front and rear portions 23 and 25 defines a forwardly 
facing abutment surface 29. A longitudinally extending upwardly and 
rearwardly opening slot 31 formed in a central part of the rear portion 25 
terminates at its forward end in an upwardly and forwardly inclined cam 
surface 55. The upper end of the cam surface 55 terminates at the upper 
edge of the abutment surface 29. The front portion 23 is separated from 
the rear portion 25 along a transverse line of separation indicated at 39 
and best shown in FIG. 8. In the forward end of the housing there is 
formed a plurality of parallel slots 35, 35 which extend vertically across 
the front wall 19 and open forwardly therethrough. Contiguous portions of 
the slots 35, 35 extend for some distance through the bottom wall front 
portion 23 and open downwardly therethrough. 
A resilient latch tab 37 connected to a housing 16 near its forward end by 
an integral hinge is normally biased to a position wherein it extends 
rearwardly and upwardly away from the top wall, as best shown in FIG. 9. 
The latch tab has latching surfaces which cooperate with latching surfaces 
on an associated plug receptacle (not shown) to releasably retain the 
connector assembly 12 in assembled relation with the receptacle in a 
manner well known in the telecommunication art. 
Spring contacts or terminals 41, 41 are mounted at the forward end of the 
housing, substantially as shown in FIGS. 8, 16 and 17, each contact being 
mounted within an associated slot 35. The illustrated connector assembly 
12 has 8 slots 35, 35, each slot containing an associated contact 41. Each 
contact 41 is formed from a piece of plated resilient phosphor bronze wire 
anchored in the housing 16 and has a resilient cantilever contact portion 
43, disposed within the cavity 17 and normally forming a 45 degree angle 
with the top wall 21. 
The insert 18 is made from dielectric plastic material and generally 
complements portions of the cavity 17 in which it is received. It includes 
a forward end portion 45, which has a generally rectangular cross section 
generally complementing the cross section of the forward end portion of 
the cavity 17, and a somewhat larger generally rectangular rear portion 
47. A plurality of outwardly opening slots 49, 49 equal in number to the 
slots 35, 35 are formed in the front, top and bottom walls of the front 
portion and extend rearwardly for some distance within the slot portions 
in the bottom wall. The slots 49, 49 are arranged for registry with the 
contact portions 43, 43 when the insert 18 is positioned within the 
housing 16, as will be hereinafter further described. 
An integral locking member 51 is formed centrally of the rear portion 25 
adjacent its forward edge and extends below the lower surface of the rear 
portion substantially as shown in FIGS. 16 and 17. The locking member 51 
has a rearwardly facing abutment surface 53 and a generally forwardly 
facing cam surface 57 which is inclined rearwardly and downwardly from the 
forward edge of the rear portion 47. A pair of longitudinally spaced apart 
cable retaining ribs 59, 59 project upwardly from the top of the rear 
portion 47 and extend transversely thereacross, as best shown in FIGS. 16 
and 17. 
The illustrated cable 14 is a substantially flat under carpet telephone 
cable and contains a plurality of insulated parallel solid electrical 
conductors C, C. Such conductive jacket dielectric cable is manufactured 
by Brand-Rex Company, Willimantic, Conn. and marketed under the trademark 
TELETAPE. Bare end portions of the individually insulated conductors C, C 
are rigidly supported in slots 49, 49 in the insert 18 and are maintained 
in biased engagement with associated spring contact portions 43, 43 within 
the housing 16 by the insert 18, as best shown in FIG. 17. The insert is 
retained in snap-in assembly with the housing, as will be hereinafter 
further discussed. 
The tool of the present invention is used to prepare the terminal end 
portion of a cable for assembly with an insert and to assemble the 
insert-cable subassembly within a connector assembly housing with 
sufficient force to assure proper snap-in engagement of the insert with 
the housing whereby to establish effective electrical contact between the 
various conductors C, C and associated spring contacts within the housing 
and to retain the cable in assembly with the connector assembly. 
The illustrated tool 10 has at least one wire stripper for preparing a 
cable, such as the cable 14, for termination by a connector assembly, such 
as the assembly 12 and further includes means to facilitate assembly of an 
eight-position modular connector, such as the connector 12, with 
sufficient force to assure proper connection to the cable using a readily 
available prying tool such as a screw driver or the like. For a more 
complete disclosure of electrical connector assemblies of the type which 
may be assembled using the tool 10 reference may be had to my copending 
U.S. patent application Ser. No. 144,830 for ELECTRICAL CONNECTOR 
ASSEMBLY, filed Apr. 29, 1980, now U.S. Pat. No. 4,373,766, issued Feb. 
15, 1983, and assigned to the assignee of the present invention, which is 
hereby adopted by reference. Such connector assemblies are manufactured by 
Connector Technology Corporation, Wethersfield, Conn. 
Considering the tool 10 in further detail and referring further to FIGS. 
1-7, the illustrated tool has a generally rectangular body designated 
generally by the numeral 20 and is preferably molded from durable plastic 
material. A recess 22 formed in a central portion of the body 20 opens 
upwardly through the body top wall of the body for receiving a partially 
assembled connector assembly and restraining it to move in at least a 
rearward direction relative to the tool body 20, as will be hereinafter 
further discussed. The recess 22 is defined by a front wall 24, a rear 
wall 26, a pair of opposing side walls 28, 28 a stepped bottom wall, which 
includes a front portion 30 and a rear portion 32 at a somewhat lower 
elevation than the front portion, and a rearwardly facing wall 34 located 
at the junction of the front and rear portions 30 and 32. Another recess 
36 formed in the body 20 opens upwardly through the bottom wall front 
portion 30 and extends transversely of the body between the side walls 28, 
28, and is defined by a front wall 38 and a rear wall 40, as best shown in 
FIG. 4. An upwardly opening groove 33 formed in the body communicates with 
the rear end of the recess 22 for a purpose which will be hereinafter 
explained. 
The illustrated tool 10 has three wire insulation strippers indicated 
generally at 42, 44 and 46. The wire stripper 42 is particularly adapted 
to strip the outer insulation jacket from a cable which has a round or 
circular cross section and comprises a cylindrical aperture 48 formed in 
the body 20 and opening through the lower surface of the body and the 
bottom wall portion 32, as best shown in FIGS. 4 and 7. A stainless steel 
blade 50 molded in the body has a rectilinear edge which is exposed within 
and extends across a portion of the cylindrical aperture 48, substantially 
as shown. The wire strippers 44 and 46, located at opposite ends of the 
body 20, are substantially identical structures which differ only in 
dimension, as will be hereinafter further discussed. 
The wire insulation stripper 44 is typical and essentially comprises a pair 
of blades 52, 52 mounted in fixed position in the body 20 and having 
exposed parallel edges. More specifically, the forward end portion of the 
body 20 has a relatively deep upwardly opening recess defined by 
downwardly and inwardly inclined surfaces 54, 54 which terminate at a 
longitudinally extending slot 56 which opens through the forward end of 
the body. Another somewhat shallower recess is formed at the forward end 
of the body and opens downwardly and outwardly through the forward end. 
The latter recess is defined, in part by upwardly and inwardly inclined 
surfaces 58, 58 which terminate at the slot 56. The blades 52, 52 are 
preferably molded in fixed position within the body and have opposing 
parallel edges disposed within the slot 56, substantially as shown. The 
forward corners of the blades 52, 52 are chamfered to define an outwardly 
diverging throat 60 which opens through the forward end of the body 20. 
The wire insulation stripper 44 is particularly adapted for stripping flat 
cable, such as the cable 14, size AWG No. 26 (0.015 max. diameter) and for 
this reason the letter "F" is imprinted on the body at the forward end to 
designate the flat cable stripper. The edges of the blades 52, 52 are 
spaced apart at least 0.018 inches so that the wire conductors which 
comprise the cable will not be seriously nicked by the hardened steel 
blades. 
As previously noted the wire insulation stripper 46 is substantially 
structurally identical to the stripper 44 previously described. The 
stripper 46 is primarily adapted for stripping the conductors which 
comprise a round cable size AWG No. 24 (0.020 max. diameter) and for this 
reason the rear end portion of the tool is marked with the letter "R" to 
designate the stripper used to prepare "round" cable or cable of circular 
cross section. However, the stripper 46 may also be used to strip the 
outer insulation jacket from a flat cable, as will be hereinafter 
discussed. The edges of the blades which comprise the stripper 46 are 
spaced apart at least 0.023 inches to prevent damage to the conductors, as 
previously described. 
In applying an eight-position modular connector assembly to a flat four 
pair conductive jacket dielectric cable (AWG No. 26) a multiple strip 
insulation configuration, as illustrated in FIG. 11 is preferred to 
eliminate risk of shorting. More specifically, it is generally desirable 
that the insulation on each of the bare conductor end portions extend 
beyond the outer insulation jacket, designated J, as best shown in FIG. 11 
to facilitate attachment to a connector assembly with minimum risk of 
shorting. The flat cable 14 is first inserted into the stripper 46, marked 
"R" with an end portion of desired length "A" extending beyond the 
stripper blades as indicated at A in FIG. 12. A pulling force is next 
applied to the cable in the direction of the arrow in FIG. 12 to strip the 
outer cable sheath or jacket J leaving the insulation on the various 
individual conductors C, C in tact. The individual insulated conductors C, 
C are next inserted into the insulation stripping tool 46, marked "F", 
with the blades of the wire stripper incising the insulating on the 
individual conductors C, C a distance "B" from the free end of the cable. 
The cable is then pulled through the stripper to develop the bare 
conductor length "B" as shown in FIG. 11. 
Alternatively, the cable 14 may be prepared by prestressing the free end 
portion of the cable outer jacket J, that is stretching it to a position 
somewhat beyond the free end portions of the associated insulated 
connectors C, C contained within, as shown in FIG. 14, wherein the 
location of the end portions of the conductors relative to the stretched 
cable jacket is indicated by the broken line C'. While this stretching 
force is maintained, the cable 14 is inserted into the insulation stripper 
44, marked "F" whereby the blades 52, 52 cut throgh both the outer 
insulation jacket and the insulation on the various individual conductors 
C, C. Force is then applied to the cable to pull it through the tool and 
strip the free outer end portion of the insulation jacket and insulation 
from the end portions of the conductors C, C. Cutting the outer jacket 
with the stripping tool releases the stressing force on the jacket 
allowing the cut end portion of the jacket J to snap back to the position 
shown in FIG. 11 wherein the insulation on the various individual 
conductors extends some distance outwardly beyond the outer end portion of 
the jacket. 
The cable end portion is next positioned adjacent the upper surface of the 
insert 18. The bare end portion of each conductor C is positioned within 
an associated slot 49 in the upper wall of the insert and bent downwardly 
into a portion of the slot 49 defined by the forward end of the insert. 
Thereafter, the extending bare end portion of each conductor is bent 
rearwardly and upwardly to a position wherein it lies within a portion of 
an associated slot defined by a lower part of the insert. 
The insert 18 with the cable end portion positioned thereon is next 
inserted into the cavity 17 to a position of partial assembly. The 
partially assembled connector assembly 12 is now positioned within the 
tool cavity 22, substantially as shown in FIG. 16. The distance between 
the forwardly facing rear wall 26 and the rearwardly facing wall front 24 
on the body 20 is substantially greater than the distance between the 
front surface of the housing 16 and the rear surface of the insert 18 of 
the partially assembled connector assembly 12, that is, the overall length 
of the partially assembled connector assembly 12, as measured from front 
to rear. Thus, when the partially assembled connector assembly 12 is 
positioned within the cavity 22 there is sufficient space between the 
forward end of the housing 16 and the wall 24 to permit insertion of a 
prying element, such as the screwdriver blade, shown in FIG. 16 and 
designated by the letter S. The front wall 24 provides a fulcrum for 
supporting the screwdriver S in a first position to move the connector 
assembly 12 rearwardly relative to the tool body 20 in response to prying 
force applied to the screwdriver S in the direction of the arrow in FIG. 
16. The rear wall 26 provides an abutment to prevent rearward movement of 
the insert 18 whereby the housing 16 moves rearwardly relative to the 
insert in response to the applied prying force. The recess side walls 28, 
28 cooperate with associated housing side walls 27, 27 to restrain the 
partially assembled connector assembly for movement in at least a rearward 
direction relative to the tool body 20. 
The tool wall surface 38 which is spaced rearwardly of the wall surface 24 
provides a second fulcrum which supports the screwdriver S in a second 
position whereby further prying force may be applied to the connector 
assembly 12 in the direction indicated in FIG. 17 to effect forceable 
engagement of the coengageable inclined cam surfaces 55 and 57. Further 
rearward movement of the housing 16 relative to the insert 18 causes the 
resilient rear portion 25 to be downwardly bowed whereby to allow the 
locking member 51 to travel past the cam surface 55. At this point the 
resilient portion 25 snaps from its bowed condition to its normal or 
undeformed position bringing the abutment surfaces 29 and 53 into 
substantial abutting engagement whereby the locking member 51 cooperates 
with the bottom wall of the housing 16 to retain the insert 18 and its 
associated cable end portion in a locked position within the housing 16. 
Upon completion of the assembly each of the conductors C is engaged with 
an associated spring contact portion 43 within the housing 16, 
substantially as shown in FIG. 17. 
The tool 10 may also be used to apply a modified form of the connector 
assembly 12 (not shown) to a round cable, that is a cable having a 
circular cross section, and containing a plurality of individual solid 
conductors which are twisted relative to each other and about the axis of 
the cable. 
In preparing a cable of the aforedescribed general type an end portion of 
outer insulation jacket is first removed by inserting the end portion of 
the cable into the cable stripper 42 through the aperture 48. The tool is 
then rotated about the axis of the cable with the blade 50 in cutting 
engagement with the cable jacket. After the jacket or sheath has been 
severed the cable is removed from the tool and the sheath stripping 
operation completed by bending the cable at right angles to the 360 degree 
cut section and thereafter removing the sheath by pulling it from the 
cable conductors. The nylon and manufacture identification strings in the 
cable may be cut by inserting them into the insulation stripper at either 
end of the tool and wiping them against the stripper blades. Removal of 
insulation from the various individual conductors may now be accomplished 
by spreading the conductors into and holding them in a substantially flat 
fan shaped pattern, in or out of color sequence as required by the given 
application. While the conductors are held in a flat pattern, that is with 
the various conductors in parallel adjacent relation the insulated 
conductors are inserted into the stripper 46, marked "R", as shown in FIG. 
15, whereby the insulation is cut. Thereafter, the insulation is removed 
from the end portions of the wire conductors by pulling the cable through 
the stripper. 
The conductor assembly is assembled with the round cable in the manner 
generally aforedescribed. The configuration of the connector housing and 
insert for use with round cable differs somewhat from the configuration of 
the housing 16 and insert 18, previously described. Reference may be had 
to Applicant's aforementioned pending application for disclosure of such a 
connector assembly. However, for complete understanding of the present 
tool it is sufficient to note that the groove 33 is provided in the tool 
to accommodate round cable on a partially assembled connector assembly 
when the connector assembly is positioned within the cavity 22. The 
procedure for completing the assembly of a connector assembly with a 
"round" cable using a prying element in conjunction with the tool 10 is 
substantially identical to the procedure previously described. 
In FIG. 10 there is shown another tool embodying the invention and 
indicated generally by the reference numeral 10a. The tool 10a is similar 
in most respects to the tool 10 previously described and differs therefrom 
only in the location and arrangement of its round wire insulation 
stripper. More specifically, the tool 10a has a generally rectangular body 
20a which has a recess 22a opening through its top wall. Wire insulation 
strippers 44a and 46a are located at opposite ends of the tool, 
substantially as aforedescribed. A wire stripper 42a which is particularly 
adapted for stripping the outer insulation jacket from a cable having a 
circular cross section, comprises a parti-cylindrical aperture 48a which 
extends vertically through the tool body 20a and opens through one side 
edge of the body, substantially as shown. A blade 50a, molded or otherwise 
secured in fixed position within the body 20a extends across a portion of 
the parti-cylindrical aperture 48a, substantially as shown. The edge of 
the blade 50a is spaced from the peripheral surface of the aperture 48a a 
distance substantially equal to the thickness of the cable jacket to be 
stripped, the latter distance being indicated by the numeral 62. The width 
of the side wall opening is preferably substantially less than the 
diameter of the aperture 48a. This arrangement allows easy access to the 
blade 50a through the side opening in the tool to facilitate convenient 
cutting of identification strings and the like while protecting the blade 
from accidental contact with other tools or hardened objects when the tool 
10a is carried in a tool box or the like.