Shielded cable connector

An electrical connector is provided, whose housing is securely connected to the shields of shielded cables while conductors of the cables are connected to contacts of the connector, in a low cost arrangement. A ring (52, FIG. 3) is installed under the braided shield of the cable to provide a bulged shield portion 54 which is pressed against a conductive cable-supporting surface (76, FIG. 4) of the housing. The ring is preferably of elastomeric material, and a simple tie (100, FIG. 6) can surround the cables and a housing retainer (66) to securely hold them together, the tie lying in slots (81-83) of the retainer.

BACKGROUND OF THE INVENTION 
Connectors that are attached to shielded cables generally require a means 
for securely connecting the cable shield to the conductive housing of the 
connector. Such connection to the shield must occur while one or more 
central conductors of the cable are connected to contacts of the 
connector. An emerging use for such connectors is for power cables that 
can supply current to electric vehicles to recharge their batteries. One 
current approach uses three separate shielded cables extending to a 
connector, with the shield of each cable connected to the housing of the 
connector and with a single central conductor of each cable connected to a 
contact of the connector. The connector must be designed for mass 
production at low cost, while reliably connecting to each cable in a 
manner that facilitate field repairs. 
SUMMARY OF THE INVENTION 
In accordance with one embodiment of the present invention, an electrical 
connector is provided for attachment to a shielded cable, which assures 
reliable electrical connection between the cable shield and the connector 
housing in a simple, low cost, and easily reparable construction. A ring 
lies under a portion of the cable shielding to provide a bulged shield 
portion that can be reliably connected to the housing. The bulged shield 
portion is pressed against an electrically conductive cable-receiving 
surface formed on the housing, to provide high pressure for a lower 
resistance connection. 
The ring can be formed of elastomeric material. The cable and other similar 
cables can be pressed against corresponding cable-receiving surfaces of a 
retainer, and a tie can surround the cables and retainer to press the 
bulged portions of all cables securely towards corresponding conductive 
cable-receiving surfaces. The retainer has arms between cable-receiving 
surfaces, and the arms have slots that receive the tie to prevent it from 
moving axially. 
The novel features of the invention are set forth with particularity in the 
appended claims. The invention will be best understood from the following 
description when read in conjunction with the accompanying drawings.

DESCRIPTION OF THE PREFERRED EMBODIMENTS 
FIG. 1 illustrates a connector system 10 which includes a receptacle 
connector 12 that mates with a plug connector 14. The particular connector 
12 is designed to mount on an electrically energized vehicle to receive 
electrical power for recharging batteries of the vehicle. The receptacle 
connector 12 is designed to receive power from a utility line to supply 
power for recharging the batteries. Three shielded cables 20, 22, 24 
extend in a rearward direction R from a rear end portion 26 of the 
receptacle connector, with conductors of the cables connected to 
corresponding pin contacts 30 at the front end portion 32 of the 
connector. The pin contacts are designed to mate with corresponding socket 
contacts 34 of the plug connector, which has three shielded cables 36 
extending from its rear end. 
As shown in FIG. 3, each shielded cable such as 20 includes a central cable 
conductor 40, an insulation 42 extending around most of the length of the 
conductor, a flexible shield 44 extending around most of the length of the 
insulation, and an outer insulative jacket 46 extending around most of the 
length of the flexible shield. The pin contact 30 has a rear part 50 that 
is crimped onto the cable conductor 40. A means is required to reliably 
electrically connect the flexible shield 44 of the cable to the conductive 
housing of the connector in a low cost manner that facilitates repairs. 
In accordance with the invention, applicant provides a ring element or ring 
52 which lies beneath the flexible shield 44 to create a bulge at 54 in 
the shield on either side of the ring. The shield 44 is a braiding formed 
of multiple strands of stainless steel, which is maintained at ground 
electrical potential. The ring 52 can be installed in a number of ways, as 
by first slipping the ring over the shield 44, and then folding a portion 
of the shield backward over the ring and itself. The shield extends 
largely in the form of a tube centered on the axis 56 of the cable except 
for the backward-folded portion that forms a bulge around the ring. The 
bulge 54 in the flexible shield provides a region that can be pressed with 
high pressure against the conductive housing of the connector to establish 
good electrical contact between the shield and the housing. 
FIG. 4 illustrates the rear end portion 26 of the housing 60 of the 
connector 12. The housing is electrically conductive, in that it has an 
electrically conductive surface. Applicant prefers to form the housing 60 
with an injection-molded thermoplastic body 62 that is not highly 
electrically conductive. Applicant then plates the body with a highly 
electrically conductive plating 64 of copper and nickel. The conductive 
plating form an electromagnetic barrier to minimize emission of 
electromagnetic waves. Of course, the entire housing could be formed of 
conductive material. The housing rear portion includes a retainer 66 that 
is largely in the form of a "Y" as viewed along the axis 68 of the 
connector. The retainer has three thick arms 71-73 radiating from the 
axis, and forms three concave cable-supporting surfaces 76-78 that each 
extends between and along each pair of adjacent arms. Applicant places 
each cable such as 20 on one of the cable-support surfaces such as 76, 
with the bulge 54 positioned to lie against the surface. 
As shown in FIG. 5, applicant uses a tie wrap 100 to hold the cables on the 
retainer. The tie wrap 100 presses the bulge 54 in the braided shield 44 
firmly against the cable-support surface 76. The fact that the tying force 
applied by the tie device 100 presses a small area 81 of the shield 
against the conductive surface 76, results in high pressure-low resistance 
electrical contact between the shield 44 and the conductive surface 76. 
As indicated in FIG. 6, the tie wrap includes a flexible band 102 and a 
band latch 104. One end 106 of the band is fixed to the latch 104, while 
the other end passes through a slot in the latch 104, where a resilient 
finger 108 engages teeth 110 on the band to prevent its loosening. Such 
tie wraps are widely used in the automotive industry to tie groups of 
cables together. Such wraps are available at very low cost, and 
refinements in their design have been made over the years so that they are 
highly reliable in tying cables or the like tightly together. By the use 
of such bands to hold the cables to the housing, and to press the bulges 
against the cable-supporting surfaces to provide high contact pressure 
between the cable shield and the housing, applicant provides a low cost 
way for holding the cables to the housing. The finger 108 of tie devices 
can be readily deflected away from the teeth of the band to remove the tie 
device, for repair of the connector. 
The retainer 66 (FIG. 4) has three slots 81-83, that each extend 
perpendicular to the housing axis 68 and across the radially outer surface 
of each of the arms 71-73. As shown in FIGS. 6 and 7, the band 102 of the 
tie device extends through the slots 81-83, which keep the band in a fixed 
position along the length of the retainer. 
Although the tie devices are flexible, they are not highly elastic. 
Applicant prefers to form the ring 52 of elastomeric material such as soft 
rubber, and uses what is commonly referred to as an O-ring. Such rings are 
available at low cost. The elasticity of the O-rings assure continued firm 
pressure between the cable shields and the conductive housing surface, 
despite any slight loosening of the tie due to changes in temperature and 
the like. The cable-receiving surface 76 preferably has about the same 
radius of curvature as that of the cable, or of the bulge 54. The surface 
76 can be provided with a groove 85 (FIG. 5) therein to prevent axial 
movement of the bulge 54, to assure that the bulge does not move from 
beneath the tie band 102. 
To connect a cable to the connector, applicant first prepares the cable as 
shown in FIG. 3, with various parts of it trimmed, with the ring 52 
installed, and with the shield 44 wrapped backward to lie around the ring 
and form the bulge 54. As shown in FIG. 2, the cable is then inserted 
through a rubber grommet 120 until a retainer 122 snaps behind a shoulder 
on the pin contact 30 to hold it in place. The same procedure is followed 
for the other two shielded cables. Finally, the tie wrap 100 is tightly 
wrapped about the bulging portions of the cable shields to securely hold 
the cables on the retainer and assure good electrical contact between the 
cable shields and the conductive surfaces of the retainer. 
As shown in FIG. 2, the plug connector 14 also has shielded cables such as 
36 which are of similar construction to that of the shielded cable 20. The 
cable 36 includes an O-ring 130 lying within a folded-back cable braided 
shield 44, which lies on a retainer 134. However, instead of using a tie 
wrap, applicant forms a rear portion 136 of the plug connector housing in 
two parts 140, 142 (FIG. 8) that are tied together by screw and nut 
fasteners 146, 148. When the two parts 140, 142 are fastened together and 
approach one another, surrounding elements 150, 152 of the parts 140, 142 
press the bulges in the cables such as 36 against the retainer 134 to 
securely hold the cables in place and to make good electrical connections 
with their shields in the same manner as for the receptacle connector, 
except that two rigid housing parts are used instead of a tie wrap. 
FIG. 9 illustrates another assembly that is similar to that of FIG. 5, 
except that the elastomeric ring 52 is installed against the cable 
insulation 42, and the braided shield 44A lies only around the outside of 
the ring to form a bulge at 54A. Also, the cable-supporting surface 76A of 
the retainer 66A, has a groove 90 in which the bulge 54A lies. The 
pressure applied by the tie 100 forces the bulge 54A into the groove 88, 
to establish contact between outer corners 86, 88 of the groove and the 
shield 44A. 
Thus, the invention provides an electrical connector and shielded cable 
combination, which assures good electrical connection between the shield 
of a cable and a conductive surface of the connector housing, in a low 
cost manner that facilitates assembly and disassembly. A ring is provided 
that lies under the cable shield to form a protrusion or bulge around the 
ring, that facilitates obtaining high pressure contact of the shield and a 
conductive surface of the connector housing. The connector housing 
includes a retainer with a cable-supporting surface. With the cable, 
especially the bulge around the ring thereof, pressed towards the 
cable-supporting surface, high pressure contact is established between the 
surface and shield. A plurality of such cables can be tightly secured to 
the housing by a tie wrap. The retainer includes grooves that receive the 
tie wrap to prevent it from moving axially. Each ring is preferably formed 
of elastomeric material to provide resilience that assures tight contact 
despite loosening of the tie wrap or other device that presses the cable 
towards the cable-supporting surface. 
The novel features of the invention are set forth with particularity in the 
appended claims. The invention will be best understood from the following 
description when read in conjunction with the accompanying drawings.