Ruggedized, sealed quick disconnect electrical coupler

A quick disconnect electrical coupler for connecting an electrical cable, or cord, to circuitry in a closed housing forms a sealed, high strength, impact resistant connection between the housing and a flexible conduit within which the electrical lead is disposed. The quick disconnect electrical coupler includes a conduit adapter in sealed engagement about an aperture in the housing which is coupled to the conduit by means of a threadable compression connection. Electrical leads coupled to circuitry in the housing terminate in a plurality of conductive pins disposed within an inner connector housing adapted for mating engagement with a conventional socket-type lead connector coupled to the electrical cable. A connector adapter is disposed about the inner connector housing and within the conduit adapter and is in sealed engagement with these two components. The connector adapter includes an outer threaded portion adapted for coupling to the socket-type lead connector within the liquid tight, sealed combination of the conduit adapter and the flexible conduit, which combination also maintains the electrical leads in fixed position within the conduit and conduit adapter and protects the electrical cable and connector from impact damage. Another embodiment replaces the connector adapter and inner connector housing with a ringed, tapered seal for securely coupling the conduit adapter and flexible conduit in a moisture-tight sealed manner while maintaining the electrical leads in fixed position within the electrical coupler.

FIELD OF THE INVENTION 
This invention relates generally to liquid tight electrical connectors and 
is particularly directed to a ruggedized, sealed quick disconnect coupling 
arrangement for connecting an electrical lead to circuitry within a 
housing. 
BACKGROUND OF THE INVENTION 
An electrical circuit disposed within a closed housing is typically 
connected through the housing to appropriate external circuitry such as a 
power supply or a data/control signal source or processing circuit. The 
electrical circuit is generally enclosed in a housing to isolate it from 
the environment, insulate it from other circuits and conductors, and 
mechanically protect it from impact damage. An electrical lead typically 
extends through an aperture in the housing and is connected to circuitry 
within the housing. The lead may also be coupled to an external cable by a 
suitable connector. Frequently several leads extend through the housing's 
aperture and are coupled to a multi-lead cable via a multi-pin connector. 
An O-ring may be inserted in the aperture of the housing and disposed 
about the leads or cable to provide a limited seal for the leads and 
circuitry within the housing and to protect the leads from damage by 
contacting that portion of the housing defining the aperture through which 
the leads extend. This arrangement affords only limited cable protection 
and isolation of the internal circuitry from the environment external to 
the housing. For example, this arrangement is subject to leakage of 
moisture and other contaminants into the housing as well as impact damage 
to the cable and connector extending from the housing. Where a conduit 
connector extends from the housing, a potting compound is frequently 
incorporated in the connector to fill voids therein. This increases the 
cost of the installation and still does not ensure a leak-free connection. 
The present invention addresses the aforementioned problems of the prior 
art and by providing a ruggedized, sealed quick disconnect electrical 
coupler for a cable extending through an aperture in a housing containing 
electrical circuitry. 
OBJECTS AND SUMMARY OF THE INVENTION 
Accordingly, it is an object of the present invention to provide a 
ruggedized, liquid-tight sealed detachable coupling arrangement for an 
electrical cable. 
It is another object of the present invention to provide a sealed coupler 
for connecting an electrical cable to circuitry within a generally closed 
housing which protects the cable from mechanical damage while allowing the 
cable to be easily and quickly disconnected from the housing. 
Yet another object of the present invention is to provide a quick 
disconnect coupling arrangement for a multilead electrical cable, or cord, 
which is comprised of a minimum number of components, protects the cable 
from mechanical damage, and insulates the cable and electrical connection 
from moisture and foreign material. 
This invention contemplates a quick disconnect sealed electrical coupler 
for connecting an electrical cable to leads from a sensor circuit within a 
housing, the electrical coupler comprising: a conduit adapter coupled to 
the housing and disposed about an aperture therein for forming a seal with 
the housing, wherein the sensor leads pass through the aperture in the 
housing and are disposed within the conduit adapter; a conduit disposed 
about the electrical cable and coupled to the conduit adapter for 
isolating the electrical cable from its surroundings a quick disconnect 
coupler for connecting the electrical cable to the sensor leads; and a 
connector adapter for coupling the sensor leads to the quick disconnect 
coupler, wherein the connector adapter is in sealed engagement with the 
conduit adapter and the quick disconnect coupler engages and maintains the 
sensor leads in fixed position within the electrical coupler.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
Referring to FIG. 1, there is shown an exploded side view of a ruggedized, 
sealed quick disconnect electrical coupler 10 in accordance with the 
present invention. The left-hand portion of the electrical coupler 10 is 
shown in phantom in order to illustrate additional details of the 
invention. A portion of the assembled quick disconnect electrical coupler 
is shown partially cutaway in FIG. 2 and in a lateral plan view in FIG. 3. 
The quick disconnect electrical coupler 10 connects an electrical cable, or 
cord, 60 to a sensor 12. The sensor 12 includes a housing 13 typically 
comprised of metal or plastic. The housing 13 is generally closed, having 
an aperture therein within which is positioned a conduit adapter 30. 
Disposed within housing 13 is a sensor 14 such as of the electromagnetic 
type including a coil, or windings, 16 and a ferrite core 18. Coil 16 is 
electrically coupled to various electronic components, or circuitry, 22 
disposed on a printed circuit (PC) board 20 within sensor housing 13. A 
plurality of conductors 24 are electrically coupled to the electronic 
components 22 and terminate in a plurality of conductive pins 46 disposed 
within a connector housing 42. 
The electrical leads 24 extend out of the aperture of the sensor housing 13 
and are disposed within the conduit adapter 30. Details of the conduit 
adapter 30 are shown in the end-on and lateral sectional views of FIGS. 4a 
and 4b. The conduit adapter 30 includes an aperture, or slot, 30c 
extending the length thereof through which the electrical leads 24 extend. 
Conduit adapter 30 further includes a hex nut, or flange, 30a on a first 
end thereof and a threaded portion 30b on a second, opposed end portion 
thereof. The threaded portion 30b is disposed on an outer surface of the 
conduit adapter 30, while an inner shoulder 30d is disposed within the 
conduit adapter's aperture 30c. Threads 30b are a standard tapered pipe 
thread which form a liquid-tight seal when connected to a mating female 
thread in a preferred embodiment. 
Also disposed within sensor housing 13 is a reinforcing, or stiffener, 
plate 28. Reinforcing plate 28 also includes an aperture therein which is 
aligned with the aperture in sensor housing 13. Reinforcing plate 28 is 
preferably comprised of metal or a high strength plastic for increasing 
the strength and ruggedness of the coupler installation. Disposed on an 
inner surface of reinforcing plate 28 about the aperture therein are a 
plurality of ears 26. Ears 26 are disposed in closely spaced relation 
about the hex nut end 30a of the conduit adapter 30 to prevent rotation of 
the conduit adapter when threadably engaged by means of a lock nut 32. 
Tightening of lock nut 32 on the threaded portion 30b of conduit adapter 
30 outside of sensor housing 13 allows for secure attachment of the 
conduit adapter to the sensor housing 13 in a liquid-tight seal. The 
secure attachment of the conduit adapter 30 to sensor housing 13 also 
protects the electrical leads 24 and various components of the electrical 
coupler disposed within the conduit adapter from damage by impact forces. 
Disposed within the aperture 30c of the conduit adapter 30 is a connector 
adapter 40. Connector adapter 40 is also generally cylindrical in shape 
and includes an aperture 40d extending the length thereof as shown in the 
lateral sectional and end-on views of the connector adapter of FIGS. 5a 
and 5b. Connector adapter 40 further includes a first end 40a, a second 
threaded end portion 40c, and an outer flange 40b disposed therebetween. 
With connector adapter 40 inserted in the aperture 30c of conduit adapter 
30, the connector adapter's flange 40b engages the inner shoulder 30d of 
the conduit adapter in a sealed manner. Connector adapter 40 is preferably 
press fit into secure engagement with conduit adapter 30 to ensure secure 
coupling between these two components. 
Inserted within the aperture 40d of the connector adapter 40 is a connector 
housing 42. Connector housing 42 is also generally cylindrical in shape 
and includes an aperture 42a extending the length thereof. Disposed within 
connector housing 42 is a spacer, or partition, 48 having a plurality of 
apertures therein. Each of the apertures within spacer 48 is adapted to 
receive and engage a conductive pin 46. Each of the pins 46 is coupled at 
one end thereof to a respective one of the electrical leads 24 extending 
from the electronic components 22 on the PC board 20. Spacer 48 maintains 
the conductive pins 46 in fixed position within the connector housing 42 
and ensures proper spacing between these pins. Spacer 48 also supports and 
maintains fixed positioning of the electrical leads 24 within the 
electrical coupler 10. An O-ring seal 44 is disposed on an outer portion 
of connector housing 42 and is adapted for secure engagement with an inner 
portion of connector adapter 40 when the connector housing is inserted 
into the connector adapter. The inner wall of the connector adapter 40 as 
well as the outer wall of the connector housing 42 may be tapered to 
ensure tight-fitting engagement of O-ring seal 44 with these two members. 
O-ring seal 44 is preferably comprised of a high strength, compressible 
material such as neoprene, while connector adapter 40 and connector 
housing 42 are preferably comprised of metal or a high strength plastic 
material. As in the case of attachment of connector adapter 40 to conduit 
adapter 30, connector housing 42 is preferably press fit into the 
connector adapter. 
Coupled to the connector adapter 40 is a plug-type lead connector 50. Lead 
connector 50 has at a first end a plurality of socket-like receptacles 
(not shown) each adapted for receiving and engaging a respective contact 
pin 46 in the connector housing 42. Lead connector 50 also includes at one 
end thereof an internal threaded portion shown in FIG. 1 in dotted line 
form for engaging and coupling to the threaded end portion 40c of the 
connector adapter 40. Lead connector 50 further includes an outer gripping 
portion 50a to facilitate rotational displacement of the lead connector in 
connecting and disconnecting it from connector adapter 40 and the contact 
pins 46 within the connector housing 42. Coupled in a conventional manner 
to the plug-like terminals of the lead connector 50 and extending from a 
second end thereof is the multi-conductor cable 60. Lead connector 50 
allows for the quick coupling and decoupling of electrical cable 60 from 
the sensor assembly 12. 
Disposed about electrical cable 60 is a sealed connector 62 of conventional 
design. Sealed connector 62 includes a connector body 68, a compressible 
ferrule 70, and a conduit 72. Connector body 68 includes a first end 68a 
having an internal threaded portion 68d adapted for engaging the threaded 
portion 30b of the conduit adapter 30. A hex nut flange 68b is disposed 
about the connector body 68 to facilitate rotational displacement of the 
connector body in connecting and disconnecting it from the conduit adapter 
30. Disposed on a second, opposed end of the connector body 68 is an 
external threaded portion 68c. Connector body 68 further includes an 
elongated aperture extending the length thereof within which is positioned 
the electrical cable 60. 
The second threaded end portion 68c of the connector body 68 is adapted to 
receive the compressible ferrule 70 as well as an end of conduit 72. A 
compression nut 72a disposed about conduit 72 is adapted for engaging the 
threaded portion 68c of the connector body 68. Tightening of compression 
nut 72a on the threaded end portion 68c of the connector body 68 provides 
a compression fit between connector body 68 and conduit 72. Compressible 
ferrule 70 is preferably comprised of brass or a plastic material. Ferrule 
70 forms a seal between the connector body 68 and conduit 72, which also 
preferably is comprised of a metal or a high strength plastic material. 
The combination of conduit adapter 30 and the sealed connector 62 isolates 
electrical leads 24 and cable 60 as well as the connection therebetween 
from moisture and other external contaminants. It should be noted that the 
side views of the electrical coupler shown in FIGS. 2 and 3 do not include 
elements of the sealed connector 62 shown in FIG. 1 for simplicity. 
Referring to FIG. 6, there is shown a ruggedized, sealed electrical coupler 
80 in accordance with another embodiment of the present invention. As in 
the previously described embodiment, the electrical coupler 80 shown in 
FIG. 6 is adapted for coupling an electrical cable 104 to circuitry 94 
within a sealed sensor housing 82 in a moisture proof, ruggedized 
installation which protects the electrical components and conductors from 
mechanical damage as well as from exposure to external contaminants. 
Sensor 82 includes a housing 84 within which are disposed an 
electromagnetic sensor 86 comprised of a coil 88 and a ferrite core 90. 
The coil 88 is electrically coupled to various electronic components, or 
circuitry, 94 on a PC board 92 within the sensor housing 84. Circuitry 94 
is, in turn, coupled to a plurality of conductors 93 which extend through 
an aperture in sensor housing 84 and are disposed within cable 104. 
As in the previous embodiment, a reinforcing plate 98 is disposed in 
contact with an interior wall of the sensor housing 84 and about an 
aperture therein. Attached to and extending from the reinforcing plate 98 
are a plurality of spaced ears 100. Reinforcing plate ears 100 are 
positioned in closely spaced relation to a hex nut flange end portion 96a 
of a conduit adapter 96 positioned within the aperture of the sensor 
housing 84. The reinforcing plate ears 100 prevent rotation of the conduit 
adapter 96 when a threaded end portion 96b of the conduit adapter 96 is 
engaged by a lock nut 102. Tightening of lock nut 102 forms a moisture 
proof seal between sensor housing 84 and the conduit adapter 96. 
Inner threads 114d on a first end portion 114a of a connector body 114 are 
adapted to engage the threaded portion 96b of the conduit adapter 96. A 
hex nut flange 114b disposed about the connector body 114 facilitates 
coupling the connector body to the conduit adapter 96 as well as its 
removal therefrom. A second, opposed end of the connector body 114 is 
provided with an external threaded portion 114c which is adapted for 
receiving a compression nut 120 disposed about a conduit 118. A 
compressible ferrule 116 inserted within connector body 114 and engaged by 
one end of conduit 118 forms a seal between the connector body and the 
conduit. The combination of connector body 114, compressible ferrule 116 
and conduit 118 forms a sealed connector 112 with the conduit adapter 96 
extending from sensor housing 84. As shown in FIG. 6, cable 104 is 
inserted through connector body 114, compressible ferrule 116 and conduit 
118. 
The ruggedized, sealed electrical coupler 80 further includes a seal 110 
positioned within adjacent ends of the conduit adapter 96 and connector 
body 114. Seal 110 is generally cylindrical and includes an aperture 
extending the length thereof within which is positioned cable 104. Seal 
110, which preferably is comprised of a high strength, compressible 
material such as neoprene, includes an internal spacer, or partition, 
shown in FIG. 6 in dotted-line form as element 110e, for engaging and 
maintaining proper spacing of cable 114 within conduit adapter 96 and 
sealed connector I12. Disposed on a first end of seal 110 is a first end 
O-ring 110a which is adapted for tight-fitting engagement with an inner 
shoulder 96d disposed within the aperture 96c of the conduit adapter 96. 
Seal 110 further includes a second intermediate O-ring 110b disposed along 
the length of the seal for similarly engaging the conduit adapter 96 about 
the aperture 96c therein. A second, opposed end 110c of seal 110 is 
provided with a bevelled edge to ensure tight-fitting engagement with an 
inner portion of connector body 114. In proceeding from the first O-ring 
110a to the second end 110c of seal 110, the seal is tapered outward to 
further ensure tight sealing engagement between the seal and connector 
body 114. The combination of conduit adapter 96, seal 110 and sealed 
connector 112 provides a water tight and mechanically rugged connection 
for cable 114 to sensor circuitry 94. 
There has thus been shown a ruggedized, sealed quick disconnect coupler for 
connecting an electrical cable to leads from circuitry within a closed 
housing which affords a sealed, high strength, impact resistant connection 
between the housing and a flexible conduit containing the cable. Sealed 
coupler components engage the electrical leads from the housing and 
maintain the leads in fixed position within the coupler as they exit the 
housing. Quick disconnect threaded couplers facilitate coupling and 
decoupling the liquid tight seal as well as the electrical connection 
between the sensor leads and the cable. 
While particular embodiments of the present invention have been shown and 
described, it will be obvious to those skilled in the art that changes and 
modifications may be made without departing from the invention in its 
broader aspects. For example, while the conduit adapter is shown coupled 
to the conduit via a quick disconnect threaded coupling arrangement, the 
present invention may also be used where the conduit is connected to the 
conduit adapter in a more permanent installation such as via a clamp or 
other attachment means. Therefore, the aim in the appended claims is to 
cover all such changes and modifications as fall within the true spirit 
and scope of the invention. The matter set forth in the foregoing 
description and accompanying drawings is offered by way of illustration 
only and not as a limitation. The actual scope of the invention is 
intended to be defined in the following claims when viewed in their proper 
perspective based on the prior art.