Ignition cable connector

A connector for terminating the distributor end of ignition cables includes a conductive insert fitted within an outer boot. A spring-lock barrel of the conductive insert is arranged within a generally cylindrical head portion of the boot and a wire-piercing prong which extends radially outwardly from the barrel extends generally centrally into a cylindrical neck portion of the boot. The neck portion has a hinged cover with insulation piercing prongs to prevent axial withdrawal of a cable from the connector.

BACKGROUND OF THE INVENTION 
The present invention is directed generally to a prefabricated distributor 
boot assembly for an automotive ignition cable and more particularly to a 
distributor boot assembly which can be quickly and easily installed onto 
the end of an ignition cable in a manner to provide a reliable mechanical 
and electrical connection thereto. 
The need for the present invention is apparent upon reviewing the history 
of automotive ignition wires. Between 1920 and 1957, mechanics generally 
fabricated their own ignition wires by cutting a lead from a roll of wire 
and fastening terminals on the opposite ends and placing boots over the 
terminals. A five-step process was involved: cutting the wire, stripping 
th wire, folding the conductor back, attaching the terminal, and pulling 
the boot over the terminal. 
Between 1957 and 1975, federal regulations began to require radio static 
suppression. The inner conductor of ignition wires were changed to 
graphite impregnated string, thereby making field stripping hazardous 
because of possible damage to the fragile inner conductor. 
During this time between 1957 and 1975, the custom spark plug wire set 
became the mode of the replacement parts business. The custom set is a set 
of spark plug wires which are precut and terminated in the factory of its 
origin and ultimately installed by the mechanic or retail purchaser. The 
custom set requires no tool or labor on the part of the installer to fit 
to the proper engine size. 
In the early 1970's, under hood temperatures were increasing dramatically 
because of the introduction of pollution control devices. As temperatures 
increased, former jacketing on spark plug wires became less effective. 
Silicone was substituted for hypalon because of its higher temperature 
ranges. Electronics were becoming more important for the same reasons. In 
1975, electronic high energy ignition systems became the industry 
standard. The evolution of electronics increased voltage in the ignition 
system to 35,000 volts. Formerly, 7 mm jacketing on ignition wires was 
satisfactory in containing the voltage surging through the spark plug 
wires but another millimeter of insulation was added to contain the high 
voltage of the new system. 
This added millimeter of insulation and changes in the termination of spark 
plug wires nearly demanded a factory terminated distributor terminal and 
boot. Since the termination of the distributor end became even more 
complex, the practice of many mechanics and do-it-yourselfers of using 
universal spark plug wire sets was practically eliminated. A universal 
spark plug wire set is a set of spark plug wires which has a factory 
terminated spark plug end and requires that the purchaser cut, strip, fold 
and terminate the distributor end. This procedure requires knowledge and 
special tools. 
Currently, there are more than 1600 years, makes and models of automobiles 
and trucks on our roads. This requires production and inventory of more 
than 150 custom spark plug wire sets to meet 90% coverage of automobiles 
and trucks in service today. Hence there is a parts proliferation. With 
constantly changing design and performance characteristics of engines, a 
virtual parts explosion is being experienced. By 1985, the cost of 
inventory and the number of spark plug wire sets required to meet supply 
and demand will have nearly doubled. 
Accordingly, a principal object of the invention is to provide an improved 
ignition cable connector. 
Another object is to provide an ignition cable connector which may be 
readily installed by even an inexperienced operator to achieve a reliable 
mechanical and electrical connection between the connector and cable. 
Another object is to provide an improved ignition cable connector which may 
be installed without special tools. 
Another object is to provide an ignition cable connector which will enable 
the use of universal spark plug wire sets for modern high energy systems. 
Finally, a further object is to provide an ignition cable connector which 
is simple and rugged in construction, inexpensive to manufacture and 
efficient in operation. 
SUMMARY OF THE INVENTION 
The ignition cable connector of the present invention includes an 
electrically conductive insert mounted within an electrically insulating 
boot. The conductive insert has a spring-lock barrel with an integral wire 
piercing prong extended radially from it. The spring-lock barrel is 
positioned within an upright generally cylindrical head portion of the 
boot and the wire-piercing prong extends outwardly through a side wall 
opening of the head portion into a generally cylindrical neck portion. The 
neck portion has a hinged cover so that an ignition cable may be easily 
inserted therein with its center conductor being pierced by the 
wire-piercing prong of the conductive insert. A hinged cover on the neck 
portion has an insulation piercing means on its interior surface for 
preventing axial withdrawal of the ignition cable upon closing of the 
hinged cover. A locking mechanism maintains the hinged cover in its closed 
position. 
The hinged cover may simply be a top wall of the neck portion or the boot 
may be split through both the neck portion and head portion so that the 
hinged cover is connected to the remainder of the neck portion by the 
split head portion sections. 
The ignition cable connector of the invention thus enables the distributor 
end of an ignition cable to be quickly and easily terminated in a manner 
to provide a reliable mechanical and electrical connection and without 
special tools. The invention thus eliminates the need to field strip wires 
and reduces the process for terminating the wire by three steps. The 
present invention furthermore eliminates the need for special skill or 
training to terminate ignition cables. Finally, the ignition cable 
connector of the present invention will operate to substantially reduce 
parts proliferation in the automotive parts industry and will make the 
replacement of ignition cables more affordable for all.

DESCRIPTION OF THE PREFERRED EMBODIMENTS 
The ignition cable connector 10 shown in FIGS. 1-4 includes an outer boot 
12 which covers and insulates a conductive insert 14. The boot 12 is a 
somewhat L-shaped flexible member having an upright generally cylindrical 
head portion 16 which includes a top wall 18, an open bottom end 20 and a 
side wall 22 having an opening 24. Opening 24 provides access to the 
generally cylindrical neck portion 26 which extends generally radially 
from the head portion 16 in registration with the side wall opening 24. 
Neck portion 26 has an elongated channel-shaped base portion 28 and a 
hinged cover 30 pivotally movable between the dotted line open position 
and solid line closed position of FIG. 3. The hinged cover 30 is 
preferably pivotally movable about a pivot axis extended transversely of 
the neck portion, as indicated generally at 32. A lock means such as the 
interlocking press-fit Z section edges 29 and 31 on cover 30 and base 
portion 28 serve to retain the hinged cover in its closed position. 
The conductive insert 14 may be formed from an integral blank 32 of metal 
material as indicated in FIG. 4 to provide the part shown in FIG. 2. 
Insert 14 includes an elongated spring-lock barrel 34 having an upright 
center axis 36 (FIG. 3), a top wall 38 and an integral wire-piercing prong 
40 extended generally radially from the barrel 34. Barrel 34 is an 8 mm 
female barrel adapted to be snapped onto a high energy distributor cap. 
The wire-piercing prong 40 is preferably arcuate in cross section for added 
strength. It is preferably disposed perpendicular to the barrel 34 and 
axially displaced from the top wall 38 of the barrel by an inclined 
connector link 42. It is preferred that the pivot axis 32 for the hinged 
cover 30 be situated closer to the head portion 16 and the free end 44 of 
the wire-pierciing prong 40 so that the prong is both visible and easily 
accessible when assembling the connector. 
As shown in FIG. 3, the conductive insert 14 is arranged in the boot 12 
with the spring-lock barrel 34 in the head portion 16 and the 
wire-piercing prong 40 extending generally centrally into the neck portion 
26. The boot is sufficiently flexible to enable the conductive insert to 
be press-fit therein during assembly. The boot material should be more 
rigid than rubber, however, and thus may be provided as a plastic such as 
polyvinyl chloride or a thermal plastic compound for accommodating the 
high and low heat ranges associate with an automotive engine. 
The conductive insert 14 is preferably formed from tin plated steel, 
stainless steel or brass. 
In FIG. 3, connector 10 is shown as installed on the end of an ignition 
cable 46 which has a center conductor 48 and an annular insulation cover 
50. Cover 50 may include both a fiberglass insulation layer 52 and an 
outer silicon cover 54. 
In operation, hinged cover 30 is pivoted upwardly to the dotted line open 
position of FIG. 3 whereupon the ignition cable 46 is axially pressed into 
channel portion 28 so that the wire-piercing prong 40 enters the center 
conductor 48 to establish an electrical connection between them. The 
hinged cover 30 is then lowered to its closed solid lin position of FIG. 3 
and snap-locked in that position by the interlocking edges 29 and 31. 
To prevent axial withdrawal of the cable 46, the underside of hinged cover 
30 is provided with an insulation piercing means such as the plurality of 
integral interiorly protruding prongs 56 shown in FIGS. 1 and 3. Similar 
prongs 58 are preferably provided in the interior surface of the 
channel-shaped base portion 28 as well. 
An alternate insulation piercing means is shown in FIGS. 5 and 6. Instead 
of the integral prongs 56 and 58, a generally L-shaped tab 60 has an 
elongated leg portion 62 embedded within the hinged cover 30 as shown in 
FIG. 5 with a foot portion 64 extending interiorly from the cover for 
piercing the insulation of a cable inserted into the connector. As shown 
in FIG. 6, the tab 60 is of somewhat arcuate shape and the interior edge 
of foot portion 64 may be serrated as at 66 for an improved bite into the 
cable insulation 50. 
Another embodiment of the invention is shown in FIGS. 7-9. The connector 70 
is similar to connector 10, with the primary difference being that the 
conductive insert 74 has a spring-lock barrel 76 of the 7 mm male type. 
The open bottom end 73 of the boot head portion 78 is formed sufficiently 
wide to provide a recess 80 to accommodate a snap-fit of the spring-lock 
barrel 76 onto a distributor. The 7 mm male type connector 70 is otherwise 
similar to the 8 mm female model connector 10 as evident by a comparison 
of FIGS. 9 and 3. 
FIG. 10 illustrates an alternate embodiment for a boot 82. In this 
embodiment, the head portion 84 and neck portion 86 are split along a 
plane intersecting the side wall opening 88 and disposed generally 
parallel to the central axis of the head portion to define a pair of split 
connector portions 90 and 92 which are hingedly connected together along 
one side wall as indicated at 92. 
Boot 82 is of a type adapted to receive the 7 mm male type conductive 
insert 74 of FIG. 8. When the split connector portions 90 are pivoted to 
their closed positions of FIG. 11, the boot 82 quite closely resembles the 
boot 72 of connector 70 in FIG. 9. In the embodiment of FIG. 10, however, 
the neck portion 86 of split connector portion 90 may be regarded as the 
hinged cover and the neck portion 86 of split connector portion 92 may be 
regarded as the channel-shaped base portion. 
The means for locking the split connector portions 90 and 92 together in 
their closed position includes interlocking edges 96 and 98 on the neck 
portions of split connector portions 90 and 92 and similar interlocking 
edges 100 and 102 on the head portion of split connector portions 90 and 
92. 
Whereas the interlocking edges 96, 98 and 100, 102 provide an effective 
voltage barrier, additional mechanical locking may be afforded by tabs 104 
having hooked end portions adapted to be inserted through coacting latches 
106 on connector portion 92. A similar tab 108 and latch 110 arrangement 
is provided on the head portion. The hooked end 112 of tab 108 presents a 
rearward shoulder 114 which engages the edge of latch 110 to secure the 
connector portions in their closed and latched positions. 
Thus there has been shown and described a prefabricated distributor boot 
assembly which provides a reliable mechanical and electrical connection 
and which can be assembled with any conventional pliers. Several 
connectors according to the invention can be quickly and easily installed 
to provide a high quality tailored set of ignition cables.