Note: Descriptions are shown in the official language in which they were submitted.
1~L51~52
This invention relates to electrical connectors.
More particularly, this invention relates to connectors in
which a plurality of electrical contacts are mounted therein,
with each contact having a filter element for grounding out
unwanted RF signals which might otherwise pass through the
connector and cause interference in the associated electrical
circuit.
Electrical connectors having a plurality of filter
contacts are known in the prior art. In such systems, the
contacts are generally fixed to a body assembly which is
permanently mounted to the shell of the connector. One
example of such a prior art system is shown in U.S. Patent
4,029,386 issued June 14, 1977 to Krantz and Fort for
"Connector Having A Plated Plastic Ground for Filter Contacts".
In many applications of such prior art connectors, the single
pi0ce shell with contacts permanently mounted therein is
advantageous. However, in some applications the shell is a
very complicated and expensive piece of equipment.
Nevertheless, the filter, the pins, the sockets and
the interconnecting current paths may possibly fail under
adverse conditions and in response to loads. The failure of
a pin or a socket or a filter in prior art applications
caused the entire assembly (contacts, body, and shell~ to
be discarded and a new shell and contacts being employed.
When the shell is very expensive, it is undesirable
to discard the entlre assembly (including the shell) upon
failure of the filters, the contacts, or the interconnecting
current paths. An apparatus which would reuse the shell would
be advantageous, but the permanent mounting of the assembly
'B PC~ C, k ', .~"~
,
" 1151~5Z
to the shell is not conductive to non-destructive removal of
the contacts of contact-containing body.
Accordingly, the prior art filter connectors have
undesireable limitations in some situations.
The present invention overcomes the limitations of
the prior art filtered-contact electrical connectors by
providing an electrical connector assembly containing filter
contacts which are mounted in an easily removable module for
quick, simple and non-destructive removal from the shell upon
failure of any part of the module.
The moaule containing the filter contacts is secured
within the shell by a mechanical attachment such as
interfitting screw threads or an interference fit or a
mechanical latch. Moisture protection of the connection
between the module and the shell, if desired, can be easily
employed in the present assembly.
According to the present invention there is provided
an electrical connector having a shell with an interior wall,
a forward mating face and a rear face, the shell interior wall
including a shoulder facing towards one of the faces, and a
filter module having a forward face and a rear face ana being
removably disposed within the shell. The filter module has a
body with a plurality of apertures extending therethrough
and a plurality of electrical terminals, each electrical
terminal comprising a contact portion and a filter element,
each filter element having a portion disposed within one of
the apertures of the body. The filter module further has a
body of solder filling each of the apertures and surrounding
the filter element disposed in the aperture thereby rigidly
- 2
~B pC/_'f'
- lJ~5~,~S~
mounting the electrical terminal to the body. Means is
provided for electrically connecting the filter elements to
the shell, the means including an electrically conducting
member extending outwardly from the body to engage the shell
and an electrically conducting element contacting each body
of solder and the electrically conducting member, thereby
electrically connecting each of the filter elements to the
conducting member. Mounting means is provided for removably
mounting the filter module withln the shell interior with a
portion of one of the filter module faces engaging the
shoulder of the shell. The mounting means includes a
releasable retaining member having a portion which defines a
second shoulder facing toward the other of the shell faces.
The second shoulder engages a portion of the other face of
the filter module so that when the filter module is held
between the shoulder and the releasable retaining member, the
filter elements of the connector are electrically connected
to the shell through the conducting member and the conducting
element; and when the releasable retaining me~ber is released,
the removable filter module may be easily and non-destructively
removed from the shell.
In a specific embodiment of the invention, the
releasable retaining member is held within the shell in an
interference fit and held in place by friction without
interfitting threads.
Other objects and advantages of the present invention
will be apparent to one skilled in the art in view of the
following description of the invention and claims and
accompanying drawings.
B - 3 -
pc/~k'
- ~L151~:S2
370-77-0160
Other objects and advantages of the present invention
will be apparent to one skilled in the art in view of the
following description of the invention and claims and
accompanying drawings.
.:-
,
- :
.
S~.~52
370-78-0160
BRIEF DESCRIPTION OF THE DRAWINGS
FIGURE 1 is a partial cross-sectional view of an
electrical connector assembly including a cross-sectional
view of a filter module of the present invention.
FIGURE 2 iS a partial cross-sectional view of the
connector assembly of FIGURE 1, showing the external
portion of the module with a portion of the shell cut
away.
FIGURÉ 3 is a cross-sectional view of the filter
module of the present invention.
FIGURE 4 shows a view of a threaded sleeve which
could be used to retain the filter module within the
connector shell.
FIGURE S is a view of an alternate embodiment of
means for mounting the module according to the present
invention.
~S~;~S2
370-78-0160
DETAILED DESCRIPTION OF THE DRAWINGS
FIGURE 1 is a partially cutaway view of a filter
contact assembly of the present invention. An electrical
connector shell 100 has a filter contact module 200
mounted therein, with a plurality of spaced, filtered
electrical contacts 300 included within the module. The
module 200 is held fixed within the shell by a retaining
member ~00. The entire assembly of the shell 100 with the
contact-containing module 200 mounted therein forms an
electrical connector which is adapted to mate with a~
other similar connector (having comple'mentary and
similarly arranged contacts) to form an electrical
connector assembly.
The shell 100 may include a number of features
standard for electrical connectors which are not relevant
to the present invention nor shown in the present
drawings: keys or keyways; external threads or coupling
nuts for coupling the shell with the other shelI; and
structure for mounting the shell to a panel.
The electrical connector shell 100 is generally
cylindrical with a cylindrical passage 110 (defined by an
inner surface of a shell wall) extending forwardly from a
rear face to a rear-facing annular shoulder 120.
The filter contact module 200, which is also
2S generally cylindrical, has a forward face 210 seated
against the rear-facing annular shoulder 120 of the shell
when the module is assembled in place within the shell
100 .
~ ~ .
' ~
.' ' ~ . , .
.
. . .
l~S1~52 370-78-0160
The exterior of the module 200 includes two annular
grooves 230 which extend about the circumference of the
module 200. A grounding strap 240 is inserted within each
annular groove. -
5The grounding straps 240 are preferably each of the
"watch band" spring type which is bowed outwardly in the
medial portion of the strap by its mounting within the
groove which is narrower than the width of the strap. The
outwardly bowed medial portion, when carried upon an
unmounted module, has a slightly larger circumference than
the circumference of the shell passage 110. This slightly
larger circumference of the grounding st~ap 240 mounts the
grounding strap in pressure contact against the interior
shell wall defining the passage 110 when the module 200 is
lS mounted within the shell 100.
Each of the filtered electrical contact terminals 300
includes a filter 320 and a forwardly-extending contact
portion 310 for mating with a complémentary contact in the
other shell. Each contact terminal 300 is mounted to the
module 200 in a passage extending through the module. The
electrical contact terminals 300 shown in FIGURE 1 are
double-ended terminals, with a second contact portion 330
extending rearwardly for mating with another contact,
although other rear portions of the contacts could be
employed to advantage.
The retaining member 400 holds the mounted module 200
in place within the shell 100 by applying a forwardly
directed force against the rear face 220 of the module
200.
30The retaining member 400 is of an annular shape with
external threaded projection 410 on the forward portion
thereof. The threaded projection 410 mates with internal
screw threads 114 carried on the rear portion of the shell
wall to allow the retaining member 400 to firmly captivate
35the module 200 in the passage 110 and urge it against the
forward shoulder 120.
~ .
~ . . .
-` ll51~S;;~
370-7~-0160
Advantageously, a rubber "o" ring seal 500 is mounted
between the retaining member 400 and the rear face 220 of
the module 200 along the peripheral edge of the passage
110 .
FIGURE 2 is a side view of the module 200 and the
retaining member 400 with only a portion of the shell 100
cutaway. As shown in FIGURE 1, the forward face 210 of the
module 200 seats against the rear-facing annular shoulder
120, and the rear face 220 of the module 200 is engaged by
the O ring seal 500, which, in turn, is held by the
retaining member 400. The external threaded projection
410 on the member is received by the internal screw thread
114 on the shell.
The grounding straps 240 are mounted around the
peripheral annular groove on the module. The grooves are
formed as depressions between successive ribs on
shoulders. Thus, one annular groove is formed between
forward rib 232 and medial rib 234, and the other annular
groove is formed between the medial rib 234 and the rear
rib 236.
FIGURE 3 shows a cross-sectional view of the filter
module 200 with two filtered electrical contacts 300
shown. The module 200 includes a central body 250 of an
electrically-conducting material such as aluminum, with a
plurality of apertures 255 extending therethrough. The
body 250 advantageously includes a central portion
including the apertures and a peripheral wall portion
which includes the three ribs 232, 234, 236 which form the
two annular grooves therebetween. The wall portion is
preferably perpendicular to the central portion and
extends forwardly and rearwardly of the central portion.
,
,:
1~5~25Z 370-78-0160
Each aperture 255 is located to receive one
electrical contact 300 in the region of the filter
element 320, with the forward contact portion (the mating
element) 310 extending forwardly and with the other end
portion (in this case, a second mating element, a pin 332)
extending rearwardly.
The contacts 300 are mounted to and held within the
apertures 255 of the body 250 by a layer of solder 260
which advantageously covers one entire side of the central
portion of the body 250 and also surrounds the filters 320
of the electrical contact terminals 300 to mount the
filters to the body 250 in mechanical àttachment to, and
in electric circuit relationship with, the body 250.
Two layers of epoxy, a forward layer 270 and a rear
laye.r 280, surround the body 250. The epoxy layers
protect the electric current path between the filters and
the body and protect the mechanical attachment of the
terminals to the body.
As previously described in connection with FIGURES 1
and 2, the grounding straps 240 are mounted within the
annular grooves formed by the ribs 232, 234, 236.
~ 5~52 370-77-0160
FIGURE 4 shows a perspective view of the retaining
member 400 of one embodiment of the present invention.
The member 400 has the external threaded projection 410 on
the forward portion. The member 400 has a rear portion
420 for manual grasping to remove or install the member
400 on the shell. A central aperture 430 through the
member allows electrical conductors or additional
electrical contacts to pass therethrough and make an
electrical circuit with the rear portion of the contacts
mounted in the module. Such electrical conductors or
additional electrical contacts are not an integral part of
the present invention, but are accommodated by the present
design of the retaining member 400.
FIGURE S shows an alternate embodiment of the present
invention which may, in certain instances, be preferred to
the embodiment of FIGURES 1-4. In this embodiment, the
module 200 is mounted within the shell 100 as in FIGURES
1-4. The wall of the passage has no screw threads, but
rather a uniform inside diameter extending rearwardly from
the rear facing shoulder (not shown in FIGURE 5). A
retaining member 600 has a forward sleeve portion 610 with
an outside diameter almost the same as the inside diameter
of the wall of the passage 110. As such, the retaining
member 600 fits within the shell 100 in a pressure fit and
is retained by friction. The member 600 includes a rear
portion 620 which may be secured for insertion and removal
of the member.
In instances where the electrical connector may be
subject to substantial vibrational forces, the threaded
retaining member disclosed in FIGURES 1-4 may become loose
and not hold the module 200 in a firm position within the
shell 100, so the embodiment of FIGURES 5 may be more
advantageous.
~51~252
370-78-0160
11
In the FIGURE 5 embodiment, there is no o" ring
seal, as it may be omitted in those instances where
moisture is not a problem.
In some instances, it may be desirable to restrict
the mounting orientation of the module within the shell.
In such instances, keys and keyways on the module and
shell passage might be used to advantage.
While the present invention has been disclosed in
some detail in the foregoing description, it will be
appreciated that there are many vari~tlons which may be
used to advantage without departing from the spirit of the
invention. For instance, other apparatus for mounting the
module within the shell could be substituted for the two
disclosed mounting members. The shell passage and module
could be of other shapes than cylindrical. Thus, the
foregoing description should be considered only as
illustrative of the present invention, which is defined by
the appended claims.
