Note : Les descriptions sont présentées dans la langue officielle dans laquelle elles ont été soumises.
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Th0 present invention relates generally to an electrical connector
and, more particularly, an improved electrical connector of the type having
plug and receptacle parts releasably intermateable to interconnect two electric
wirc cables.
An exceptionally well-received electrical connector for both domestic,
aerospace and military use, is that set forth in United States Letters Patent
4,066,315. As described in that patent, the electrical cable connector has
keyed parts which are lockingly intermated by rotation of a coupling ring, the
latter including a separate internal nut that drives the connector parts to-
gether or apart, depending upon the direction of rotation. Spring-type devices
located between the coupling housing and a connector part serve to provide
compensation for accumulated tolerances of the different connector components.
These spring-type devices, however, are sensitive to and adversely affected by
forces applied to the cable that tend to pull the connector apart. That is,
cable load sufficient to deflect the spring devices will also effect separation
of the connector parts at the interface resulting in either undesirable contact
movement, reduction or even total loss of compression at the interface seal.
The electrical connector described herein includes plug and receptacle
parts respectively interconnected to two sets of cable wires via socket and pin
contacts. On mating of the plug and receptacle parts the pin contacts are
removably received within socket contacts establishing the desired electrical
interconnection between the sets of cable wires.
The plug has an outer hollow cylindrical coupling ring which is
rotatable with respect to the plug body and includes internal threads that co-
operate with threads on the plug body outer surace. When the plug and re-
ceptacle are joined together, rotation of the coupling ring serves to drive the
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plug and receptacle toward or away from each other depending on
the direction of rotation thereby connecting and releasing the
connector parts, respectively.
In accordance with a first version of the described
invention, the plug and receptacle both include resilient inter-
face seals which are of sufficient thickness and softness as to
provide satisfactory compensation for the accumulated tolerances
of the assembled connector parts. In this manner, the need for
the separate threaded coupling nut of the referenced patent is
obviated.
As a further aspect, the coupling ring and plug body
threads can be so made as to mesh loosely thereby providing
additional tolerance compensation.
The invention may be summarized as an electrical connec-
tor having plug and receptacle parts releasably mateable for
electrically interconnecting pin and soc~et contacts respectively
carried by the connector parts, comprising: the plug part inclu~
ding a hollow cylindrical metal coupling means received about a
plug shell, said coupling means having threads formed on the inner
wall surface which mesh with threads formed on the peripheral
surface of the plug shell, the threads on said coupling means
and plug shell being dimensioned so as to provide substantial
relative movement therebetween along a direction parallel to the
cylindrical axis of the coupling means; a first insulative means
carried by the receptacle within which one of the contacts is
mounted, said first means having a soft resilient interface seal
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facing toward the plug during mating; and a second insulative
means carried by the plug shell and within the other contacts are
mounted, said second means including a soft resilient interface
seal facing the receptacle and abutting against the first insula-
tive means interface seal during matina of the receptacle parts;
the relative thicknesses and location of said soft resilient
interface seals being such that said seals will be in compression
on the connector parts being mated together.
The invention will now be described in greater detail
with reference to the accompanying drawings, in which:
Figure 1 is a fragmentary partly sectional view of a
prior art conn~ctor;
Figuxe 2 is a side elevational view of a connector of
the present invention shown in the released mode;
Figure 3 is a partly sectional elevational view of the
electrical connector of Figure 2 shown partially mated; and
Figure 4 is a partly sectional elevational view similar
to Figure 3 with parts shown fully mated.
With reference now to the drawing and particularly
Figure 1, a presently available electrical connector of the general
type to which the present invention applies is identified generally
as at 10 and is seen to include a plug 11 and receptacle 12 which
are intermated to interconnect respective sets of cable wires 13
and 14. The plug 11 includes a cylindrical shell-like coupling
ring 15 which is free to rotate about the plug. A nut 16 is loca-
ted within the coupling ring 15 and resiliently held therein by a
spring
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device 17 which enables the nut to be moved along the connector longitudinal
axis and at the same time remain unitarily related to the coupling ring. The
nut has internal threads 18 which cooperate with a complementary set of threads
19 on the peripheral surface of the plug such that when the outer end of the
coupling ring is received onto the receptacle, rotation of the coupling ring
causes the plug to move toward or away from the receptacle depending upon the
direction of rotation.
The spring device 17, which frequently takes the form of a "wavy"
washer, enables resilient movement or positioning of the nut 16 ~and thus the
coupling ring) along the connector axis serving as a compensation for connector
part tolerances. In the prior art design the contact system ~i.e., pin and
socket contacts) is referred to as "rear release" in that the contacts are
inserted and extracted from the rear (i.e., cable wire ends) of the connector.
In such connectors a hard dielectric socket interface is used and this necessi-
tates the described two-piece coupling to allow for manufacturing tolerances and
provide constant interface sealing.
Turning now to Figure 2, the electrical connector of this invention
is seen to include in its major elements a receptacle 20 and plug 21 which are
fitted together during the connection mode of the connector for interconnecting
sets of cable wires 22 and 23. After the receptacle and plug are initially
partially joined, a hollow, cylindrical coupling ring 24 is rotated which in
a way that will be described causes the plug to be driven against and onto the
receptacle to firmly seat pin contacts within the socket contacts. A plurality
of generally rectangular keys 25 are circumferentially arranged about the re-
ceptacle shell exterior for fitting receipt within a corresponding arrangement
of keyways (not shown) located inside the coupling ring 2~ and plug 21 for
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insuring proper arrangement and mutual location of the connector contacts with
respect to each other. As described to this point the present connector is
constructed and operates substantially the same as the connector in the refer-
enccd United States patent.
With reference particularly to Pigure 3, the receptacle and plug are
shown in initial mating stages with the receptacle 20 received within the plug
21 but with the pin contacts 26 not yet received within the socket contacts 27
to effect electrical contact for the cable wires.
The receptacle 20 is seen to consist generally of a hollow cylindrical
metal shell having a bore that passes completely therethrough. An insert as-
sembly 28 is located within the receptacle bore and includes a grommet 29, an
interface seal 30 and a centrally arranged insert body 31, all of which are
integrally related together.
The grommet 29 is a generally cylindrical member having a plurality
of openings 32 extending therethrough parallel to the cylindrical axis, which
openings in use receive the individual cable wires 22. The grommet is construct-
ed of a relatively soft and r0silient material such as rubberJ for ex~mple.
Insert body 31 is generally cylindrical and constructed of a relative-
ly hard, rigid and highly insulative plastic. A plurality of openings are
provided in the body in alignment with the grommet openings 32, which openings
are of such cross-section as to retain the socket contacts 27 received therein.
A circumferential flange 34 abuts against a shoulder in the receptacle inner
wall to position the insert body.
The interface seal 30 is cylindrical in shape and so dimensioned as
to fit snugly within the receptacle bore. A plurality of openings extend
through the seal in alignment with the openings in insert body 31 and also those
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in the grommet. Preferably, the seal 30 is constructed of a relatively soft
and resilient insulative material such as rubber, for example.
In assembly, the grommet 29, insert body 31 and interface seal 30
are suitably arranged as a unit with the openings of each aligned and secured
within the receptacle by a snap-ring 35. The socket contacts 27 are inserted
into grommet openings 32, then through the insert body openings, and finally
the interface seal openings so as to extend outwardly of the seal ou~er face 36.
Removal of the socket contacts can be conveniently achieved by pushing them out
at the face 36 using a plunger device.
The receptacle also includes a set of threads 37 on its outer peri-
phery for conventional connection to cable shielding means, for example. Still
further, a rim or flange 38 is provided for wall mounting, if desired.
The plug 21 is a generally cylindrical, hollow metal shell having a
set of relatively large threads 39 formed on an outer margin of the end that
faces the receptacle during matingO The coupling ring 24 is an oversi~e
cylindrical metal shell received onto the plug and which includes an internal
set of threads 40 which mesh with the plug threads 39.
A flange 41 at the outer end of the coupling ring 24 extends radially
inwardly a limited amount for releasably engaging the receptacle in a manner to
be described. At the opposite end of the coupling ring a snap-ring 42 is
located within an internal groove 43 to limit rearward threading of the plug
by the couping ring. A detent spring 44 provides audible and tactile means for
indicating fully mated condition as more fully described in the referenced
United States patent. In addition; the detent spring prevents the coupling ring
from inadvertently rotating loose.
The inner diameter of the plug bore at the end carrying threads 39 is
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such as to permit fitting receipt over the open end of the receptacle 20. An
internal groove includes an 0-ring 45 for sealing the connector parts against
the ingress of dirt, dust and moisture. An annular spring 46 is located just
inwardly of the 0-ring 45 within a suitable groove and functions primarily as a
common electrical grounding means for the plug and receptacle. As in the case
of the receptacle, conventional threads 47 are provided on the plug outer end
for engagement with, say, the incoming cable shield.
A soft and resilient grommet 48 of similar construction to the re-
ceptacle grommet 29 is provided for the plug. Also, a rigid insulative plastic
insert 49 abuts against the grommet 48 and is similar in function and construc-
tion to the receptacle insert body 31. Aligned openings in the plug grommet
and insert receive the cable wires 23 therethrough. Still further, a flange 50
on the insert 49 engages an internal shoulder of the plug shell to locate the
insert.
A soft and resilient interface seal 51 is secured to the exposed face
of insert 49 and includes a plurality of openings 52 aligned with the insert
openings and passing completely through the seal. These openings 52 are each so
dimensioned as to enclose a pin contact 26 which is mounted within an insert
opening and extending into the seal opening. Moreover, the cross-sectional
dimensions of the openings 52 are sufficient to permit receipt of a socket con-
tact 27 therewithin for mating with a pin contact.
The grommet 48, insert 49 and interface seal 51 are unitarily assem-
bled and securely located within the plug shell by a snap-ring 53.
In use, the receptacle and plug are initially equipped with pin and
socket contacts arranged in the connector parts as shown in Figure 3. As a
first step in mating, the receptacle is slid into the open end of the plug and
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coupling ring, some axial orienting of the parts being necessary to align the
receptacle keys 25 (Figure 2) with keyways ~not shown) in the coupling ring
flange 41 and the plug shell. With the flange 41 located past the keys~ proper
rotation of the coupling ring draws the plug and receptacle together causing
the socket contacts 27 to enter openings 52 in plug insert 51 (Figure 3).
Further rotation of the coupling ring in the same direction moves the pins into
the sockets and when fully mated the faces of the interface seals abut (Figure
4). Rotation of the coupling ring in the opposite direction releases the plug
and receptacle.
In the described connector, manufacturing tolerances are compensated
for by the resiliency of the connector parts interface seals 30 and 51 when
brought into contact with each other. Accordingly, by this means of tolerance
compensation it is possible to replace the two-piece coupling ring construction
(i.e., coupling shell and separate included nut) of the prior art with the
single-piece coupling ring 24 described herein. This results in substantial
manufacturing material and labor savings as well as savings in assembly.
For the ensuing description of an alternate aspect of this invention~
reference is now made to Figure 4. The only difference in construction there
over the connector as depicted in Figure 3 is in the coupling ring and plug
threads 39 and 40~ respectively. That is, in accordance with this aspect the
two sets of threads are formed so that a substantial of movement or "play" can
be effected between the coupling ring and plug shell along a direction parallel
to the connector longi-tudinal axis. In this manner, still further compensation
is provided for accumulated manufacturing tolerances of the connector parts.
Mating and unmating is, otherwise, identical to that of the Figure 3 embodiment.
Although in the preferred forms previously described herein, the sock-
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et contacts are shown mounted in the receptacle and the pin contacts within the
plug, it is considered within the spirit of this invention to reverse the gender
of the contacts. Moreover, although it is considered advantageous to completely
enclose each pin contact within a cavity in the interface seal, particularly for
relatively small size contacts it may be advantageous to have the socket con-
tacts embedded or enclosed within an interface seal and the pin contacts ex-
posed.
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