Field of the Invention
[0001] This invention generally relates to the art of electrical connectors and, particularly,
to a system of providing a shielded connector assembly for connecting a round multiconductor
cable to a complementary connector having a flat array of terminals.
Background of the Invention
[0002] It is very common to mass terminate a plurality of insulated conductors to a connector.
The conductors may be provided for mass termination in a variety of forms. In round
conductor ribbon cable, for example, discrete wire conductors are disposed in a generally
flat, parallel spaced relation to each other between insulating dielectric layers
which surround and insulate the wires and form webs of insulation between them. Alternatively,
conductors may be provided in the form of a multi-cable assembly having a plurality
of insulated conductors surrounded by an outer insulation jacket of a generally round
cross-section. This latter type of cable assembly presents problems that are absent
when dealing with round conductor ribbon cable. When using a ribbon cable, the intervening
webs serve to maintain the relative position and spacing of adjacent conductors. On
the other hand, when handling discrete wire, the insulated conductors first must be
unravelled from a bundle of wires and thereafter positioned in such a manner to permit
mass termination with a plurality of terminals.
[0003] An example of such a connector system is a telecommunication system wherein a modular
unit, such as a telephone, may be provided with an external connector of the receptacle
type having a row of laterally spaced terminals which are connected electrically to
internal circuitry of the unit. Therefore, electrical connections may be made to the
internal circuitry through a flat cable terminated in a modular telecommunication
plug which is inserted into the receptacle type connector on the modular unit. The
plug is provided with a row of laterally spaced terminals which electrically engage
respective terminals in the receptacle type connector and are electrically connected
to respective terminals in the flat cable. The flat cables provide means for avoiding
any confusion as to which of the conductors in the cable is connected electrically
to which of the terminals laterally spaced in the row. However, in some instances,
it may be necessary to make electrical connections to internal circuitry of the modular
unit through a round cable, such as a coiled cord. The round cable generally does
not have the proper size or configuration for terminating in the modular plug suitable
for insertion into the receptacle type connector on the unit. In addition, the conductors
in the round cable are not disposed in predetermined side-by-side positional relationship
for electrical connection to respective terminals in the row thereof.
[0004] In order to solve the round-to-flat problems described above, various electrical
connector systems have been provided wherein adapters are incorporated in the connectors
for positioning and retaining the discrete wires of a round cable in a flat array
for termination to the flat array of terminals in a row in the respective connector.
Examples of such connectors are shown in U.S. Patents Nos. 4,713,023, dated December
15, 1987, and 4,769,906, dated December 13, 1988. The 4,713,023 patent is assigned
to the assignee of the present invention and is incorporated herein by reference.
[0005] The present invention is directed to solving the problems of terminating a round
cable in a flat terminal array connector in an extremely simple manner and eliminating
the adaptor means of the prior art.
Summary of the Invention
[0006] An object, therefore, of the invention is to provide a new and improved system of
providing a shielded connector assembly for connecting a round cable to a connector
having a flat array or row of terminals. The system includes a method of producing
the connector as well as the connector itself.
[0007] In the system to which the invention is applied herein, the round cable includes
a plurality of insulated conductors within a cable shield and drain wire and surrounded
by an outer insulating jacket. The shielded connector assembly includes an insulating
housing having receptacle means for receiving the insulated conductors in a flat array.
A plurality of terminals are mounted in the housing for termination to the received
conductors and for mating with the terminals of a complementary connector. A conductive
connector shield means is mounted on and about a portion of the insulating housing,
with a portion of the shield means extending into the receptacle means.
[0008] The invention contemplates a method of producing a shielded connector assembly with
the above basic components, including the steps of stripping a portion of the insulating
jacket from the multiconductor cable to expose the cable shield and the discrete insulated
conductors. A round conductive crimp ferrule is placed over the round multiconductor
cable in engagement with the exposed cable shield and with the exposed insulated conductors
projecting from an end of the crimp ferrule. The exposed insulated conductors then
are sorted and positioned in a flat array. The round conductive crimp ferrule is crimped
onto the round cable into a flat configuration for holding the sorted end positioned
conductors in the flat array. The cable then can be positioned in the insulating housing
with the flat array of conductors in the receptacle means for termination to the terminals
and with the crimped ferrule in engagement with the portion of the shield means extending
into the receptacle means.
[0009] As disclosed herein, the shielded connector assembly is similar to that shown in
the aforementioned 4,713,023 patent in that the connector assembly includes strain
relief means for the cable at a location generally opposite the portion of the shield
means which extends into the receptacle means. The invention contemplates providing
access means in the conductive crimp ferrule to accommodate the strain relief means
and still maintain the crimp ferrule in engagement with the portion of the shield
means. This is accomplished by cutting the round crimp ferrule at an angle to provide
a longer one side thereof than another side, the longer side being engageable with
the shield means and the shorter side providing access to the cable by the strain
relief means. Other embodiments of a crimp ferrule providing these functions are disclosed
herein.
[0010] Other objects, features and advantages of the invention will be apparent from the
following detailed description taken in connection with the accompanying drawings.
Brief Description of the Drawings
[0011] The features of this invention which are believed to be novel are set forth with
particularity in the appended claims. The invention, together with its objects and
the advantages thereof, may be best understood by reference to the following description
taken in conjunction with the accompanying drawings, in which like reference numerals
identify like elements in the figures and in which:
FIGURE 1 is an exploded top plan view of the major components of a shielded connector
assembly embodying the concepts of the invention;
FIGURE 2 is a top plan view of the assembled connector assembly;
FIGURE 3 is a vertical section taken generally along line 3-3 of Figure 1, through
the crimp ferrule of the invention;
FIGURE 4 is an end elevational view, looking toward the right-hand end of the crimp
ferrule in Figure 3;
FIGURE 5 is a vertical section, taken generally along line 5-5 of Figure 2;
FIGURE 6 is a somewhat schematic illustration of a press tool for crimping the round-to-flat
crimp ferrule of the invention;
FIGURES 7 and 8 are side and end elevational views, respectively, of an alternate
form of crimp ferrule according to the invention;
FIGURES 9 and 10 are side and end elevational views, respectively, of a further form
of crimp ferrule according to the invention; and
FIGURES 11 and 12 are side and end elevational views, respectively, of still another
form of crimp ferrule according to the invention.
Detailed Description
[0012] Referring to the drawings in greater detail, and first to Figure 1, the invention
is embodied in a shielded electrical connector assembly, generally designated 14,
which is in the form of a modular shielded plug connector assembly, such as might
be used in the telecommunications industry. The plug assembly is shown generally to
include a plug housing, generally designated 16, which mounts a grounding shield in
the form of a unitary stamped and formed metallic shell, generally designated 18,
around the rear area of housing 16, and a plurality of insulation piercing terminals
20 within the housing.
[0013] As will be seen in greater detail hereinafter, terminals 20 are adapted for termination
to discrete insulated conductors 22 of a multiconductor electrical cable 24 which
is shown in Figure 1 to be stripped to expose the ends of insulated conductors 22
as well as a conductive metallic foil 26 which is shown turned back on itself over
the outside surface of an insulating jacket 28 of the cable. Foil 26 acts as a shield
for conductors 22 and insulating jacket 28 surrounds the foil. Of course, as is known,
the foil may also comprise a braid or other ground system for the multi-conductor
cable and may also include a drain wire. Lastly, Figure 1 shows a round crimp ferrule
30 of conductive material, such as metal or the like, which is to be crimped into
a flat configuration about multiconductor cable 24, in conductive engagement with
foil 26 and exposing conductors 22 for termination with terminals 20.
[0014] Figure 2 shows shielded plug connector assembly 14 in assembled condition, with grounding
shield 18 around the rear of housing 16, and with multiconductor cable 24 projecting
from the rear of the assembly. It can be seen that housing 16 of the connector assembly
has a pair of latch arms 32 which extend laterally outwardly and rearwardly from opposite
sides of the plug connector assembly for latching the plug connector assembly in mating
engagement within a complementary receptacle connector assembly (not shown) as disclosed
in the 4,713,023 patent described above and incorporated herein by reference. Suffice
it to say, housing 16, including latch arms 32, is a unitary structure of dielectric
material, such as molded plastic or the like.
[0015] Figures 3 and 4 show that crimp ferrule 30 is generally cylindrical to define a round
through passage 34 sized to receive round multiconductor cable 24. As can be seen
in Figure 3, crimp ferrule 30 is cut at one end, as at 36, along an angle so that
a bottom wall section 38 of the ferrule is longer than a top wall section 40. For
purposes described hereinafter, the angled cut of the ferrule provides a clearance,
as indicated by double-headed arrow 42, in a vertically downward direction to define
access means from the top of the ferrule to the multiconductor cable extending through
the ferrule.
[0016] Figure 5 shows plug connector assembly 14 in completely assembled condition. It can
be seen that crimp ferrule 30 has been crimped into a flat configuration onto the
stripped end of multiconductor cable 24 about the grounding foil 26, with conductors
22 projecting forwarding from an end of the ferrule and terminated to terminals 20
which have been forced downwardly in the direction of arrow "B" to pierce the insulation
of the conductors and terminate the cores of the conductors. It also can be seen that
housing 16 has strain relief sections 44 and 46 to which access is provided by openings
48 and 50, respectively, in shield 18 (also see Fig. 2). Again, reference can be made
to the 4,713,023 patent for details of this arrangement. Suffice it to say, strain
relief section 44 provides strain relief laterally across the plug assembly for all
of conductors 22, and strain relief section 46 provides strain relief onto insulating
jacket 28 of multiconductor cable 24.
[0017] Still referring to Figure 5, it can be seen that housing 16 of plug assembly 14 has
receptacle means in the form of an interior cavity 52 for receiving the cable, the
receptacle means narrowing in a forward area 52a whereby conductors 22 are in a flat
array for termination to the row of terminals 20 described in relation to Figure 1.
It also can be seen that shield 18 has a portion 54 bent back into receptacle means
52 along the bottom wall thereof. Shield portion 54 can be seen to be in vertical
alignment with strain relief section 46. Therefore, with crimp ferrule 30 cut at an
angle as described in relation to Figure 3, the clearance 42 (Fig. 3) provides access
means for strain relief section 46 to engage insulating jacket 28 of the cable while
bottom wall section 38 of the crimp ferrule still is in engagement with shield portion
54. Therefore, ground continuity is established between shield 18, its portion 54,
crimp ferrule 30 and ground foil 26 of the multiconductor cable.
[0018] The system of the invention contemplates using grounding crimp ferrule 30 as a means
for positioning conductors 22 of round cable 28 in a flat array for termination to
the row of terminals 20. In other words, it can be seen in Figures 1, 3 and 4 that
crimp ferrule 30 initially is provided in a cylindrical configuration with its round
through passage 34 sized to receive round cable 24. However, as seen in Figure 5,
the crimp ferrule is flattened considerably, after crimping, to maintain conductors
22 in a flat array for termination to the row of terminals 20.
[0019] Specifically, the invention contemplates a method of assembling connector 16, including
the steps of stripping a portion of insulating jacket 28 (Fig. 1) from multiconductor
cable 24 to expose the cable shield or foil 26 and the insulated conductors 22. Round
crimp ferrule 30 then is placed about the round cable, with the vertically cut end
of the ferrule generally in line with the stripped end of the insulating jacket of
the cable, as seen in Figure 5. Conductors 22 then are sorted in their proper circuit
order and laid out in a flat array, being careful not to cross one conductor over
another. Crimp ferrule 30 then is crimped onto the cable by a generally flat crimping
tool to hold the conductors in their sorted and flat array. As will be seen hereinafter,
this can be accomplished by placing the subassembly of the ferrule and cable, with
the sorted conductors, in an anvil of an application tool, making sure that the top
wall section 40 of the ferrule faces downwardly from the flat array of conductors.
The crimped subassembly then can be positioned within interior cavity 52, and formed
area 52a of plug connector housing 16, as described above, with the flat array of
conductors in position for termination with terminals 20 and with the crimp ferrule
30 in engagement with shield portion 54. Appropriate application tooling then can
be used to drive insulation piercing terminals 20 into conductors 22 and to force
strain relief sections 44 and 46 of the housing into engagement with the conductors
and the insulating jacket of the cable.
[0020] Figure 6 simply shows one type of application tooling for crimping crimp ferrule
30 onto multiconductor cable 24. In particular, a tool may include a mounting base
60 for positioning on a support surface 62. A cable guide 64, a crimp anvil 66 and
a cut off anvil 68 are fixed to the top of mounting base 60. Cable guide 64 has a
trough 70 for positioning multiconductor cable 24. Crimp anvil 66 has a generally
flat anvil surface 72 for engaging the bottom of crimp ferrule 30. Cut off anvil 68
has a cutting surface 74 for trimming ends 22a from conductors 22. In actual practice,
the insulating jacket 28 of cable 24 is stripped slightly greater than the length
of the conductors 22 to be positioned within the plug assembly housing so that excess
ends 22a can be removed to provide a consistent length of the exposed conductors to
be positioned within the plug housing.
[0021] Still referring to Figure 6, the application tooling may include a press ram 76 having
a tool holder 78 for mounting a crimp punch 80 and a cutoff blade 82. The crimp punch
has a distal end 84 shaped and sized to contain the ferrule 30 and to control its
width for crimping onto the bottom of crimp ferrule 30, opposite flat surface 72 of
crimp anvil 66 to flatten the crimp ferrule and maintain the flat sorted array of
the conductors. Cut off blade 82 has a cutting edge 86 for cutting-off the ends 22a
of conductors 22.
[0022] Figures 7-12 show alternate forms of crimp ferrules for carrying out the concepts
of the invention. In each instance, the ferrule has a generally round through passage,
similar to through passage 34 of crimp ferrule 30, for positioning over round cable
24 in engagement with its grounding means, such as foil 26. More particularly, Figures
7 and 8 show a round crimp ferrule 30' having a through passage 34'. The crimp ferrule
is generally cylindrical except for a lower wall section 38' which projects outwardly
from the main portion of the ferrule. In other words, a clearance is provided, as
indicated by double-headed arrow "D", sufficient for strain relief section 46 (Fig.
5) to engage the insulating jacket of the cable, while projecting wall section 38'
of the crimp ferrule is maintained in engagement with shield portion 54.
[0023] Figures 9 and 10 show a further embodiment of a crimp ferrule 30'' which is substantially
cylindrical but which is provided with a cutout 88 in the top of the ferrule to provide
access through the cutout by strain relief section 46 of the plug connector housing,
while the bottom of cylindrical crimp ferrule 30'' is maintained in engagement with
shield portion 54.
[0024] Figures 11 and 12 show a further modification wherein a crimp ferrule 30''' is generally
cylindrical and is provided with a window 90 in the top thereof. The window provides
access means through which strain relief section 46 can be moved into engagement with
the insulating jacket of the cable, while the bottom of crimp ferrule 30''' is maintained
in grounding engagement with shield portion 54.
[0025] It will be understood that the invention may be embodied in other specific forms
without departing from the spirit or central characteristics thereof. The present
examples and embodiments, therefore, are to be considered in all respects as illustrative
and not restrictive, and the invention is not to be limited to the details given herein.
1. A method of producing a shielded connector assembly (14) for connecting a round multiconductor
cable (24) to a complementary connector having a flat array of terminals (20), the
round multiconductor cable (24) including a plurality of insulated conductors (22)
within a cable shield (26) and surrounded by an outer insulating jacket (28), and
the shielded connector assembly (14) including an insulating housing (16) having receptacle
means for receiving the insulated conductors (22) in a flat array, a plurality of
terminals (20) for termination to the received conductors (22) and for mating with
the terminals of the complementary connector, and a conductive connector shield means
(18) mounted on and about at least a portion of the insulating housing (16) with a
portion (54) of the shield means (18) extending into the receptacle means, and method
comprising the steps of:
stripping a portion of the insulating jacket (28) from the cable (24) to expose the
cable shield (26) and the insulated conductors (22);
placing a round conductive crimp ferrule (30, 30' , 30'', 30''', 30'''') over the
round multiconductor cable (24) in engagement (at 38) with the exposed cable shield
(26) and with the exposed insulated conductors (22) projecting from an end of the
crimp ferrule;
positioning the exposed insulated conductors (22) in a flat array;
crimping the round conductive crimp ferrule (30, 30', 30'', 30''', 30'''') into a
flat configuration onto the cable (24) for holding the exposed projecting conductors
(22) in said flat array; and
positioning the ferrule (30, 30', 30'', 30''', 30'''') in the insulating housing (16)
with the flat array of conductors (22) extending from the ferrule (30, 30', 30'',
30''', 30'''') in the receptacle means for termination to the terminals (20) and with
the crimped ferrule (30) in engagement with said portion (54) of the shield means
(18).
2. The method of claim 1
wherein said shielded connector assembly (14) includes strain relief means (44, 46)
for the cable at a location generally opposite said portion of the shield means, and
including the step of providing access means (42, D, 88, 90) in the conductive crimp
ferrule (30, 30', 30'', 30''', 30'''') to accomodate the strain relief means (44,
46) and still maintain the crimp ferrule in engagement with said portion (54) of the
shield means (18).
3. A method of producing a shielded connector assembly (14) for connecting a round multiconductor
cable (24) to a complementary connector having a flat array of terminals (20), comprising
the steps of:
providing a round multiconductor cable (34) including a plurality of insulated conductors
(22) within a cable shield (26) and surrounded by an outer insulating jacket (28);
providing a shielded connector assembly (14) including an insulating housing (16)
having receptacle means for receiving the insulated conductors (22) in a flat array,
a plurality of terminals (20) for termination to the received conductors (22) and
for mating with the terminals of the complementary connector, and a conductive connector
shield means (4) mounted on and about at least a portion of the insulating housing
(16) with a portion (54) of the shield means (18) extending into the receptacle means;
stripping a portion of the insulating jacket (28) from the cable to expose the cable
shield (26) and the insulated conductors (22);
turning the shield (26) back on itself over the outer insulated jacket (28);
placing a round conductive crimp ferrule (30, 30', 30'', 30''', 30'''') over the round
multiconductor cable (24) in engagement (at 38) with the exposed cable shield (26)
and with the exposed insulated conductors (22) projecting from an end of the crimp
ferrule;
positining the exposed insulated conductors (22) in a flat array;
crimping the round conductive crimp ferrule (30, 30', 30'', 30''', 30'''') into a
flat configuration onto the cable (24) for holding the conductors in said flat array;
and positioning the ferrule (30, 30', 30'', 30''', 30'''') in the insulating housing
(16) with the flat array of conductors (22) extending from the ferrule in the receptacle
means for termination to the terminals (20) and with the crimped ferrule in engagement
with said portion of the shield means (18).
4. The method of claim 3
wherein said shielded connector assembly (14) includes strain relief means (44, 46)
for the cable at a location generally opposite said portion of the shield means, and
including the step of providing access means (42, D, 88, 90) in the conductive crimp
ferrule (30, 30', 30'', 30''', 30'''') to accommodate the strain relief means and
still maintain the crimp ferrule in engagement with said portion (54) of the shield
means (18).
5. A shielded connector assembly (14) for connecting a round multiconductor cable (24)
to a complementary connector having a flat array of terminals, the round multiconductor
cable (24) including a plurality of insulated conductors (22) within a cable shield
(26) and surrounded by an outer insulating jacket (28) which is stripped from the
cable to expose the cable shield (26) and the cable shield is turned back upon itself
over the outer insulating jacket (28) to expose the insulated conductors (22), comprising:
an insulating housing (16) having receptacle means for receiving the insulated conductors
(22) in a flat array, a plurality of terminals (20) for termination to the received
conductors (22) and for mating with the terminals of the complementary connector,
and a conductive connector shield means (18) mounted on and about at least a portion
of the insulating housing (16) with a portion (54) of the shield means (18) extending
into the receptacle means; and
a round conductive crimp ferrule (30, 30', 30'', 30''', 30'''') placed over the round
connector cable (24) in engagement with the exposed cable shield (26) and with the
exposed insulated conductors (22) projecting from an end of the crimp ferrule, the
crimp ferrule (30, 30', 30'', 30''', 30'''') having been crimped into a flat configuration
onto the cable (24) for holding the conductors (22) in a generally flat array in the
receptacle means of the housing (16) for termination to the terminals (20) of the
connector assembly.
6. The shielded connector assembly of claim 5
wherein said housing (16) includes strain relief means (44, 46) for the cable (24)
at a location generally opposite a portion of the shield means (54) in the receptacle
means, and the conductive crimp ferrule (30, 30', 30'', 30''', 30'''') includes access
means (42, D, 88, 90) to accommodate the strain relief means (44, 46) and still maintain
the crimp ferrule in engagement with said portion (54) of the shield means (18).
7. The shielded connector assembly of claim 6
wherein said access means is provided by an angled end (42) of the crimp ferrule (30)
providing a short wall section (40) adjacent the strain relief means (44, 46) and
a long wall section (38) in engagement with said portion (54) of the shield means
(18).
8. The shielded connector assembly of claim 6
wherein said access means is provided by a cutout (88) at one end of the crimp ferrule
(30'').
9. The shielded connector assembly of claim 6
wherein said access means is provided by an open window (90) in the crimp ferrule
(30''').
10. A shielded connector assembly as set forth in claim 1
wherein the connector assembly (14) includes conductive connector shield means (18)
mounted on and about at least a portion of the insulating housing (16) with a portion
(54) of the shield means (18) extending into the receptacle means in engagement with
the crimped ferrule (30).