Electrical connector having cable strain relief

An electrical connector assembly for terminating flat multiconductor ribbon cable is disclosed. The connector assembly includes a base supporting plural insulation-piercing contacts in a pre-determined array. A cover, positioned over the base, is movable with respect thereto to effect cable termination to the contacts. Cable strain relief is provided by spring clips which urge an extent of cable against a side wall of the cover.

FIELD OF THE INVENTION 
This invention relates generally to electrical connectors for terminating 
flat multiconductor ribbon cable. More particularly, the present invention 
relates to an insulation displacing electrical connector which terminates 
an electrical cable upon engagement of a connector base with a connector 
cover, and which provides for cable strain relief in conjunction with the 
connector cover. 
BACKGROUND OF THE INVENTION 
Electrical connectors used to terminate multiconductor flat ribbon cable 
have long been known. Connectors of this type typically include a 
connector housing comprising a base supporting plural insulation 
displacing electrical contacts and a cover positionable over the base. The 
cover and the base define a recess which receives the ribbon cable. An 
appropriate tool may be used to displace the base and the cover towards 
one another to force the insulation displacing contacts into electrical 
engagement with the conductors of the ribbon cable. 
The terminated connector may now be connected to an appropriate electronic 
device for subsequent use. Examples of connectors such as these are shown 
in commonly assigned U.S. Pat. Nos. 4,295,704; 4,305,635 and 4,460,229. As 
the ribbon cable is held to the connector by means of the insulation 
displacing connection of the connector contacts to the conductors of the 
multiconductor cable, the interface between the contacts and the 
conductors is subject to the adverse effects of cable strain, that is, 
stress placed on the connection by movement of the cable in a longitudinal 
direction. 
Insulation displacing connectors have addressed the need for cable strain 
relief by providing separable strain relief elements attachable to the 
connector housing to clamp a portion of the flat cable between the strain 
relief member and the cover, thereby relieving the stress on the 
connection of the conductors to the contacts. An example of a strain 
relief connector of this type is shown in commonly assigned U.S. Pat. No. 
4,006,957. While adequately serving the strain relief function, connectors 
of this type must include an additional structural component by way of a 
strain relief member typically mounted to the upper surface of the 
connector cover. This greatly increases the height of the connector as the 
strain relief member and the looped cable must be accommodated above the 
cover. Thus increased spacing is necessary between vertically adjacent 
connectors. Also, the use of associated hardware, such as a connector 
ejector mechanism, is greatly inhibited. An additional limitation of 
strain relief devices which attach to the upper cover surface is that 
strain relief is provided only for cable passing through the connector in 
one direction. Thus, strain relief is not adequately provided for 
connectors which terminate cable at an intermediate location therealong in 
"daisy-chain" fashion. 
It is therefore desirable to construct a connector assembly which will 
provide for cable strain relief without the need for additional components 
secured to the upper surface of the cover. Further, it is desirable to 
provide a strain relief electrical connector which permits daisy-chain 
connection to an intermediate location of an electrical cable. 
SUMMARY OF THE INVENTION 
It is therefore an object of the present invention to provide an electrical 
connector assembly which terminates a multiconductor ribbon cable and 
which provides for strain relief of the cable. 
It is a further object of the present invention to provide an electrical 
connector assembly which includes a cable strain relief device securable 
to the cover along the longitudinal sides thereof without need to increase 
the height of the connector. 
It is a still further object of the present invention to provide an 
electrical connector assembly which permits the strain relief termination 
of a transverse extent of an elongate multiconductor ribbon cable with 
strain relief being provided on both sides of the termination extent. 
In the efficient attainment of these and other objects, the present 
invention provides an electrical connector assembly for terminating a 
transverse termination extent of an elongate multiconductor ribbon cable. 
The assembly includes a connector base having opposed upper and lower 
surfaces. A plurality of insulation piercing contacts are supported in the 
base, with the insulation displacing extents extending above the upper 
surface of the base. A cover is movably supported over the base, and 
includes a pair of longitudinal side walls and a lower cable engagement 
wall which affects movement of the cable into insulation piercing 
connection with the contacts. Clip means is supported by the cover 
adjacent a side wall of the cover. The clip means secures a transverse 
extent of the cable spaced from the termination extent to the side wall of 
the cover to provide cable strain relief thereat. 
As shown by way of the preferred embodiment herein, the connector assembly 
further includes clip means in the form of a pair of clips, each clip 
supporting a transverse extent of cable against respective opposed 
longitudinal side walls of the cover so that an intermediate location of 
the cable may be terminated by the connector assembly, and strain relief 
is provided on either side of the terminated extent.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
Referring to FIGS. 1 through 3, electrical connection assembly 10 of the 
present invention is used to terminate flat multiconductor ribbon cable 
11. Connector assembly 10 includes an elongate base 12 comprised of 
electrically insulative plastic. As shown in FIG. 3, base 12 supports a 
plurality of electrical contacts 14 in fixed position therein. Contacts 14 
are disposed in plural longitudinally extending rows, and have upper 
insulation piercing ends 16 which extend above upper surface 12a of base 
12. Contacts 14 have lower termination ends 18 adjacent lower base surface 
12b. Termination ends 18 and lower surface 12b of base 12 are designed for 
interconnection with a mating connector assembly (not shown). 
Insulation piercing ends 16 of contacts 14 are of conventional construction 
and are of the type used to electrically terminate conductors of 
multiconductor ribbon cable 11. Contacts of this type are widely used in 
electrical connectors. Also as conventionally known, contacts 14 are 
arranged so that each insulation piercing end 16 of contacts 14 is 
positioned uniquely with one conductor of multiconductor ribbon cable 11. 
Cover 20 is an elongate plastic member extending longitudinally with base 
12. Cover 20 includes a pair of opposed longitudinal side walls 22 and 24 
and transverse end walls 26 and 28. Cover 20 includes depending latch arms 
30 and 32 extending from transverse end walls 26 and 28 respectively. 
Latch arms 30 and 32 engage with transverse ends 34 and 36 of base 12 in 
latching fashion. Transverse ends 34 and 36 include latch elements 38 
which provide for dual-position latching of cover 20 to base 12. Cover 20 
has a continuous undersurface 38 which may be ribbed to engage 
multiconductor ribbon cable 11 as is known in the insulation-piercing 
connector art. Movement of cover 20 from a first latched position shown in 
the left hand drawing of FIG. 3, to a second latched position shown in the 
right hand drawing of FIG. 3 effects insulation piercing connection of 
multiconductor ribbon cable 11 to the insulation piercing ends 16 of 
contacts 14. Such movement of cover 20 toward base 12 may be accomplished 
by a suitable tool (not shown). 
Connection of contacts 14 to ribbon cable 11 is accomplished in a region 
38a defined between undersurface 38 of cover 20, and upper surface 12a of 
base 12. Such connection is accomplished along a transverse extent of 
ribbon cable 11, intermediate the ends thereof. Termination in this manner 
allows cable 11 to be "daisychain" connected to additional connectors 
along its longitudinal extent. Accordingly, as is particularly shown in 
FIGS. 2 and 3, ribbon cable 11 will extend beyond both longitudinal side 
walls 22 and 24 of cover 20. 
In order to provide strain relief for the connection of ribbon cable 11 to 
contacts 14, the present invention provides a strain relief mechanism in 
the form of clip means attachable to cover 20. 
Referring additionally to FIGS. 4 and 5, the present invention provides a 
pair of metallic spring clips 40, one of which is shown in FIG. 4. Spring 
clip 40 is an elongate member having a longitudinally extending leaf 
spring portion 42 and opposed transverse securement extents 44 at each end 
thereof. Spring clip 40 is attachable adjacent each longitudinal side wall 
2 and 24 of cover 20, the leaf spring portion 42 being springbiasingly 
supported against or in close proximity to longitudinal side walls 22 and 
24. 
Transverse end walls 26 and 28 include a recessed undulated portions 46 and 
48 respectively, adjacent upper surface 50 of cover 20. Recessed undulated 
portions 46 and 48 support transverse securement portions 44 of spring 
clip 40 to secure the spring clip to cover 20. As shown in FIG. 3, each 
recessed undulated portion 46, 48 includes a pair of upper and lower nests 
46a, 46b and 48a, 48b respectively, which accommodate the pair of spring 
clips 40, one above another, as shown in FIG. 2. 
As particularly shown in FIG. 5, leaf spring portion 42 of clips 40 is 
centrally bowed to bear against (or in close proximity to) each of 
longitudinal side walls 22 and 24 of cover 20. 
Having described the structure of the present invention, its operation may 
now be shown. 
Referring to FIGS. 1 and 2, connector assembly 10 is connected to an 
intermediate transverse portion of ribbon cable 11 in a manner 
conventionally known in the art. Cable 11 is typically placed over upper 
surface 12a of base 12, and cover 20 is placed thereover in first latched 
position on base 12. It is also contemplated that cover 20 may be 
prelatched to base 12 and then cable 11 inserted in region 38a defined 
therebetween. With conventional crimping tools, cover 20 is brought down 
onto base 12 to move cover 20 to its second latched position to effects 
insulation piercing termination of cable 11 to the conductors 14 supported 
in base 12. Electrical connection is thereby established between ribbon 
cable 11 and connector assembly 10. 
In order to provide strain relief for cable 11, spring clips 40 are 
employed. Each extending portion of cable 11a and 11b on either side of 
connector assembly 10 may be manually held in a vertical position so that 
one spring clip 40 may be inserted against each longitudinal side wall 22, 
24 of cover 20. Leaf spring portion 42 of each spring clip 40 bears 
against a transverse portion 13, 15 of cable 11 to force it against the 
respective longitudinal side wall 22, 24 of cover 20. Thus, transverse 
portions 13 and 15 of cable 11 on either side of the terminated transverse 
extent are held against the longitudinal side walls 22 and 24 of cover 20 
to provide strain relief for cable 11. As spring clips 40 bear against 
longitudinal side walls 22 and 24 of cover 20 rather than the upper 
surface 50 thereof, the height of connection assembly 10 is not increased. 
Portions 11a and 11b of cable 11 extend nearly horizontally outward from 
connection assembly 10. This permits use of a conventional latching and 
ejector mechanism (not shown) which may engage notches 52 and 54 on 
opposed longitudinal ends of upper surface 50 of cover 20. 
The present invention provides for the termination of an intermediate 
transverse extent of ribbon cable 11 with strain relief being provided on 
each spaced longitudinal side of this terminated extent. Thus, cable 11 
may be "daisy-chain" connected to several longitudinally spaced 
connectors. It is, however, contemplated that present invention may be 
employed in the termination of one end of cable 11, with strain relief 
being provided on only one side thereof. Also, each spring clip 40 
functions independently so that one clip may be removed without disturbing 
the opposite clip. 
Various changes to the foregoing described and shown structures would now 
be evident to those skilled in the art. Accordingly, the particularly 
disclosed scope of the invention is set forth in the following claims.