Note : Les descriptions sont présentées dans la langue officielle dans laquelle elles ont été soumises.
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This applioation i~ a di~ision of applica~t'~ co-
pend~ng Canadian sppli¢ation 8erial No. 173664.
The ln~entio~ rolate~ to article~ ~ultable ior u8e in
electrical oonnectors capable oi iorming both an electrical
and ph~sical connection between two or more conductore.
~lectrical and physical conneotione between two
conductors are commonly mad~ by ~oldering the overlapped end~
of the eonductore together or by crimping a connector over the
onde o~ the conduotor~. In man~ applicatione, it ie de~irable
to make a traneition ~rom a ~lat conductor (whi¢h may be, ~or
e~ample, in a ilat cablo) to a rou~d condu¢tor, but many oi the
¢ommonly u~ed connectors have been iound to b~ un~ati~iaetory
ior thisO
One method o~ joinlng a ~lat conductor to a round
eonduetor u~e~ a erimp connector ~hich i8 in the ~hape o~ a
hollo~ c~lindorO ~he end Or the ~lat conductor i9 bent into a
generally U-~haped eoniiguration along it~ longitudinal axi~
eo that thi~ end i~ capable o~ iltting into one end o~ the
hollow cylindor~ ~he round conduetor i~ in~erted into the
20 other ond oi the hollow eylinder and the cylinder i8 cri~ped
about each ¢onduetor. ~he conneetion i8 then u~uall~ potted
~ithin a re~ilie~t potting material to insulate the connection.
The cri~plng, however, oiten weakens the physical strength of
the conductor~ and the connection i~ a relativel~ bulk~ and
hea~y oneO
Overlapp~ng and eoldering of the t~o conductor~ has
al80 beon u~ed to ~oin a ilat conductor to a round conductor
but this method of con~e¢tion has the di~adva~tage o~ using
e~txa wire, ae well as requiring a time-con~u~ing and ~kil~ul
operatio~. Connection methods which emplo~ male and ~emale
member~ con~ected to the re~pective conductors have al~o been
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iO87Z65
used but they may require considerable insertion force which
must often be transmitted by the conductors them~elves,
leading, in many instances, to difficulty in connection,
bent conductors or an unsatisfactory connection.
Recently, a new type of heat-recoverable connector
for electrical conductors has been developed which has a
plurality of interconnected tubular members for receiving,
for example, individual conductors of a multi-conductor
cable. me connector may have a quantity of solder and flux
within each tubular member. When two electrical conductors
are to be joined, they are inserted into opposite ends of
a tubular member and the connector is heated to cause the
; heat-recoverable material to shrink around the conductors
and the solder tG melt and flow around the stripped ends
of the conductors. Devices of this nature are described
in Belgian Patent Specifications ~os. 110,571 and 110,572.
The present invention provides an article
suitable for use in a connector suitable for making a butt
joint between a round electrical conductor and a flat
electrical conductor, which article comprises an elongate
electrically conductive member having two end portions, one
of which end portions is shaped to contact the round
conductor and the other of which end portions is shaped to
contact the flat conductor, and the end portion which is
shaped to contact the flat conductor having a generally
flat surface portion for engagement with the flat conductor,
the electrically conductive member being provided with a
quantity of solder on at least the surface(s) thereof that
will contact the conductors and being substantially in-
fusible at the temperature to which the article is heated
to cause fusing of the solder, and at least part of the
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electrically conductive member being of open form so that
at least one of the soldered connections made, in use~ to
the article can be inspected.
As indicated above, at least part of the
electrically conductive member in the article of the in-
vention is of open form so that a soldered connection ~ade
using the article can be inspected. The said part may be,
for example, a part (for example an end portion) of the
electrically conductive member which has a generally flat
shape. Alternatively, the said part may be, for example,
a hollow portion of the electrically conductive member
having an aperture or slot therein. Preferably, at least
a part of each end portion of the electrically conductive
member is of open form.
In the article of the invention, the solder is
preferably provided on at least those surfaces of the end
portions of the electrically conductive member that will
contact the conductors. The solder is advantageously in
the form of a coating layer on the electrically conductive
member and this coating may be on only a portion of one
surface, on the whole of one surface, or on every surface
of the member. The solder need not, however, be in the
form of a coating, but could be, for example, in the form
of a ring. The solder should be placed in such a way that
it does not prevent the correct positioning of the
conductors relative to the electrically conductive member.
The electrically conductive member preferably
comprises a metal, and may, if desired, comprise a heat-
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recoverable metal. The metal should preferably be a goodelectrical conductor and should readily accept solder.
The metal i~ advantageously copper or an alloy thereof,
preferably oxygen-free copper, electro tough pitch copper
or beryllium copper. The electrically conductive member is
preferably formed from a single sheet of electrically con-
ductive material. Any of the methods known in the art for
forming a shaped article from a flat sheet of material may
be used in making the article of the invention. When the
solder is in the form of a coating on the electrically
conductive member, the sheet from which the member is made
may be coated with a layer of solder (and, if desired, flux)
either before or after it (the sheet~ has been formed into
its final shape.
One of the end portions of the electrically con-
ductive member~ is shaped to contact a round conductor and
the other end portion is shaped to contact a flat conductor.
The end portion that is shaped ~)contact a round conductor
may, for example, be U-shaped in cross-section or, alter-
natively, may be cylindrical. A cylindrical end portion
may have one or more apertures therein for viewing a con-
ductor inserted in the end portion. This aperture may,
for example, be round, or square and could if desired, be
replaced by a uniform slot or other opening which permits
inspection of a conductor inserted in the end portion.
A cylindrical end portion of the electrically con-
ductive member may, if desired, be flared to facilitate the
insertion of a conductor into that end portion. Flared ends
help to eliminate a potential source of w~akness which might
otherwise result from contact between the connector ends and
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the conductors. A cylindrical end portion may also, or
alternatively, be ~rovided with pin-retaining means which
may comprise, for example, one or more longitudinal slits
~n the end portion.
me end portion that is shaped to contact a flat
conductor may have, for example, the shape of a flattened
oval or a generally flat shape.
The article of the invention may be positioned
within a hollow body of electrically insulating material,
the hollow body having two open ends, to form a connector.
The hollow body is advantageously heat-recoverable and may
comprise, for example a crosslinked polymeric material. The
hollow body is preferably transparent to permit viewing the
soldered connection. The hollow body may extend beyond the
ends of the article, and may, if desired, be shaped to guide
the conductors into contact with the article. A heat-
activatable in~ulating material may be provided on the
hollow body.
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In one embodiment of the connector, the hollow
body may have a sheath portion and a plurality of spaced
integrally connected tubular member~ communicating with
the sheath portion, at least one, and preferably all, of the
tubular members having an article of the invention therein.
Alternatively, the hollow body may have a series of longi-
tudinal seam~ which extend from one end of the body to the
other, which seams bond opposite walls of the mernber to each
other to define and interconnect a plurality of tubular
members, at least one, and preferably alL of the tubular
members having an article of the invention therein.
The present invention substantially overcomes the
disadvantages of the prior art devices and makes it possible
to form a reliable electrical and mechanical connection
between two or more conductors. This may be accornplished
by, for example, the use of an article comprising a unitary
conductive metallic member having two open ends which contain
a coating of solder alloy and flux adjacent to at least a
portion of the inner surface of the insert. At least part
of the article is of open form to permit the viewing of
the connection after completion. An article having one
round end and one flat open end is particularly useful for
joining a round conductor to a flat conductor. One end of
the article rnay be in the form of a socket contact which can
plug into a wire wrap pin.
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One of the adYantage~ o~ a connector which in¢lude~
one or more articl~ of the in~ention is that it can have a
small overall thicknes~ and thus can be u~ed, ~or e~ample, for
the direct co~nection o~ a ilat cable with conductors whoee
centres are ~paoed 0.100 inches apart and wire plns in a printed
circult boardO ~he iact that the conne¢tor can be thin (ior
e~ample approIimately 0.070 inchee) allow~ stacking on rowe Or
0.100 inch ~pacing. In some circumstancee, the de~ice may be
only 0.030 inche~ thlck and, with ~uch a devics, conductor~
Nhose centre~ are spaced 0.050 inches apart mag be connected.
In the in~tallation oi the connectoriwhlch mag be
made u81ng the article o~ the invention, the conductor end~,
stripped if neces~ary, are in~erted into the connector a~d the
a~embly i~ heated thu~ cau~ing the hollow body (1~ this ie
heat-~hrinkable) to ~hrink about the conductor and to hold
the etrippea ends a~ainst the article(s). Th0 heat ~urther
cau~e~ the solder tand ilux, if used) to melt and electrically
to connect a pair oi conductore to each article thereby
electrically Joining the pair oi conductors~ When the
connector compri~ee a plurality of articles held within the
hollow body in a parallel and ~paced relation~hip, a parti-
cularly u~eiul devioe re~ulto.
A paxticularly ~imple and yet e~ective electri¢al
connection can re~ult ~rom the combinatio~ o~ an article oi
the invention and a heat-recoverable member. The article ma~
have a completely open, ilat, end and yet may give an exoellent
electrical oonta¢tO ~hi~ escellen¢e oi connection i~ a result
o~ the iact that the conductor is held tightly again~t the
article while the solder i~ heated to a temperature su~icient
~0 to cau~e it to melt and then cooled to allow it to ~olidi~y.
The invention will now be ds~cribed, by way oi
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example only, with reference to the accompanying drawings,
in which:
Figure 1 is a perspective view of an article
con3tructed in accordance with the pre-
sent invention together with the strip-
ped ends of two in3ulated conductors;
Figure 2 i~ a perspective view of a connector
containing an article constructed in
accordance with the present invention,
Figure 3 i8 a perspective view of the connector
of Figure 2 installed in the ends o two
in~ulated conductors, the plastic sleeve
which forms part of the connector being
shown in phantom lines;
: 15 Figure 4 is a section taken along line 4-4 of
Figure 1;
Figure 5 is a perspective view of a second em-
bodiment o~ the present invention,
Figure 6 is an end view taken along line 6-6 of
Figure 5;
Figure 7 i~ a section taken along line 7-7 of
Figure 5:
Figure 8 is a perspective view of a connector
containing a plurality of artid es of
; 25 the present invention,
. Figure 9 i-Y a perspective view of a third em-
; bodiment of the present invention; and
Figure 10 is a perspective view of the s~ipped
end of a cable which comprises a
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plurality of flat conductorq.
Referring now to the drawings, Figure 1 shows a
unitary conductive metallic member 10. The member 10 has a
generally U-shaped oval end 11, which i8 shaped to contact
a round conductor, and a flattened oval end 12, which i9
shaped to ~ontact a flat conductor. The transition between
these ends is indicated by the reference numeral 18. A
round insulated conductor 13 has a stripped end 14 which will
fit within the U-shaped end 11 of the member 10, and a flat
inRulated conductor 15 has a stripped end 16 which is capable
of fitting w~thin the flattened oval end 12. The round oval
end 11 i8 not closed in cross-section but has an opening 11a
so that it is of open form and the completed soldered joint
may thus be inspected. Similarly, the flattened oval end 12
is provided with an inspection slot 12a (see Figure 4~, and
is thus of open form.
Each end of the unitary conductive metallic member
10 is flared to facilitate the insertion of the stripped ends
14 and 16. The member 10 is coated with a thin layer of a
solder alloy 17 and is also provided with a portion of flux.
Although the solder layer is shown in the drawings as a
continuous coating on both the inner and outer surface~ of
the member, t may, instead, cover only a portion of the
member 10. For instance, the layer 17 could cover only the
inner surface of the member 10 or it could cover only those
parts of the inner surface that will contact the stripped
ends 14 and 16.
In operation, the stripped end 14 of conductor 13
is inserted into the U-~qhaped end 11, preferably ~o that it
extends to the transition 18 betwéen the round andfLattened
portions of the member 10. Similarly, the stripped end 16
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of the conductor 15 i9 inserted into the flattened oval end
12, and preferably also extends transition 18. The member 10
and stripped ends are then heated by any suitable means,
for example, infrared, hot air or induction heating, in order
to melt the flux and solder alloy layer 17 which then flowR
onto stripped ends 14 and 16 thereby creating a secure
electrical and mechanical connection. The amount of solder
used is preferably sufficient to fill the space~ between the
member 10 and the conductors. Although this is not essential,
the ends of the conductors may be tinned to facili~ate the
soldering step.
Turning now to Figure 2, the unitary member 10 of
Figure 1 is shown positioned within a heat-recoverable sleeve
25. T~,e sleeve is preferably formed from an electrically
insulating plastics material which has been conver~ed to a
heat-recoverable state so that it will tend to shrink when
it is heated to its heat-recovery temperature. Such heat-
recoverable sleeves, and some of their many uses, are dis-
closed in U.S. Patents Nos. 2,027,962 (Currie), 3,086,242
(Cook) and 3,243,211 (Wetmore). The sleeve 25 extends beyond
the ends of the member 10 so that it can cover the stripped
portions of the conductors which will be in~erted within
member 10.
Figure 3 shows the connector of Figure 2 after it
has been installed on the insulated conductors 13 and 15. The
heat-recov~rable sleeve 25, which is shown in phantom lines,
shrinks around the insulated conductors 13 and 15 and the con-
ductive member 10. Although the member 10 and the heat-
recoverable sleeve 25 are preferably installed simultaneously
(that i~, in the form of the connector device of Figure 2),
the sleeve 25 could be shrunk around an assembly made as
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described with re~pect to Figure 1. In the latter case, the
sleeve 25 must, of course, be ~lipped over one of the con-
ductor~ 13 and 15 before the latter are joined by the member
1O, and after such joining is moved into position around the
mem~er 10 to form the complete connector.
A ~econd embodiment of the present invention i5
shown in Figure 5. This Figure shows an article 30 which
comprises an outer layer 31 of a conductive material, for
example copper or beryllium/copper alloy, and an inner layer
32 of a solder alloy. The article 30 ha~ a flat end 33 (that
i9, an end with a generally flat shape) for contacting a flat
conductor and a rounded end 34 for contacting a round conductor,
and the solder layer 32 extends from the flat end to the
rounded end. An opening 35 i8 located midway along the
rounded portion of article 30. The opening 35 makes it
pos~ible to inspect the interior of article 30 when a trans-
parent heat-recoverable member is used around the article 30,
thus allowing visual confirmation that a satisfactory soldered
joint has been made.
The article 30 is shown in end view in Figure 6 and
in longitudinal section in Figure 7. The flat end 33 of the
article 30 i~ adapted for electrical connection with a flat
conductor. A stripped end portion of a cable having a
plurality of flat conductors 70, 71 and 72 which may be
electrically connected to the flat end 33 is shown in
Figure 10, the flat conductors 70, 71, and 72 are insulated
from one another by electrically insulating material 73. The
round end 34 of the artic]e 30 is adapted for electrical
connection to a round conductor, for example that identified
by reference numeral 14 in Figure 1 of the drawings.
A connector containing a plurality of conductive
articles is shown in Figure 8. A heat-recoverable member 40
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726S
of electrically in~ulating material has an open end 41 adapted
to receive a plurality of flat conductors, the ends of which
have been stripped (see, for example Figure 13). The member
40 has a second open end 42 which is adapted to receive a
plurality of round conductors or a plurality of wire-wrapped
conductor~ or the like, the ends of which have also been
stripped. The open end 41 communicates with a sheath por-
tion of the member 40 and the open end 42 communicates with
a plurality of parallel tubular members. The extent to which
the conductors are stripped should be auch that the conductor
in~ulator i8 received within member 40 but does not extend
into conductive articles, ~or example articles 43, 44 and 45,
with which the member 40 is provided. The member 40 may be
provided with a heat-activatable adhesive or oth~r softenable
material which serves to insulate and seal a conductor from
the adjacent conductors. This provides maximum voltage
break down and insulating resi3tance values after the member
40 has been heated.
In operation, a plurality of flat conductors are
stripped and inserted into open end 41. One conductor is in-
serted against each of the conductive articles 43, 44, 45 etc.,
each of which article~ has one end which has a generally flat
shape. Similarly, a stripped end of a round insulated
conductor is inserted into the other end of each of the insert~,
this second end being cylindrical in each case. The ~tripped
ends of the conductors may be tinned to facilitate the
soldering step. The member 40 is then heated by any con-
ventional means, for example infrared, hot air or induction
heating, in order to cause the heat-recoverable member 40
to recover against the inserted conductor~ and to cause the
flux and solder layers of the conductive articles to melt
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and electrically connect the conductors to the inserts.
A third embodiment of the invention i~ shown in
Figure 9. The conductive article 65 ~hown in Figure 9 ha~
a ~ocket end 66 and an end 67 having a generally flat shape.
At least the flat end 67 is coated with older. The flat
end 67 functions in a manner analogous to the flat end 33 of
insert 30 in Figure 5. The socket end 66 i~ flared outwardly
to facilitate the insertion of a conductive pin therein. A
pair of slits 68 and 69 are provided in the side wall of the
socket end 66 to give a spring action which tends to retain
a pin of an appropriate diameter which has been inserted into
end 66. The article 65 is preferably made from a metal
having good resiliency and strength, for example beryllium
copper.
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