ELECTRICAL CONTACT ASSEMBLY

CONTACT ELECTRIQUE

English Abstract

ABSTRACT:
An electrical contact assembly comprises a wire barrel onto which an
electrical conductor is connected along with a receptacle contact member
covered by a hood member. A C-shaped section of the receptacle contact
member is frictionally secured in a bore of the wire barrel with the hood
member surrounding the receptacle contact member and being crimped onto
the wire barrel. The hood has a beveled lead-in entrance to facilitate
insertion of a pin contact member into electrical connection with the
receptacle contact member at a substantially low insertion force.

Claims

THE EMBODIMENTS OF THE INVENTION IN WHICH AN EXCLUSIVE
PROPERTY OR PRIVILEGE IS CLAIMED ARE DEFINED AS FOLLOWS:

1. An electrical contact assembly of the type including a
wire barrel member to which an electrical conductor is to be con-
nected and a telescoped receptacle contact member and hood member
secured onto the wire barrel member characterized in that said
wire barrel member is formed as a screw machine member or a cold-
formed member having a rearward section to be terminated to a
conductor and bore means extending inwardly from a front end;
said receptacle contact member is a stamped and formed member and
has a receptacle contact section and a securing section friction-
ally secured in said bore means in said wire barrel member; and
said hood member has an inner end secured onto said wire barrel
member and covering said receptacle contact section.

2. An electrical contact assembly as set forth in claim 1
characterized in that said securing section is C-shaped.

3. An electrical contact assembly as set forth in claim 1
characterized in that said receptacle section has arcuate-shaped
contact-engaging members tapering toward each other toward the
front end of said hood member.

4. An electrical contact assembly as set forth in claim 3
characterized in that said receptacle section includes a tapered
channel-shaped section and a cylindrical section containing said
contact-engaging members.






5. An electrical contact assembly as set forth in claim 1
characterized in that said hood member has a beveled inner sur-
face at a front end thereof.

6. An electrical contact assembly comprising: a wire barrel
member formed as a screw machine member or a cold-formed member
and having a rearward section to be terminated to a conductor and
bore means extending inwardly from a front end; and an electrical
contact member stamped and formed and having a contact section
and a securing section, said securing section being frictionally
disposed in said bore means thereby being mechanically secured
therein in electrical engagement therewith.

7. An electrical contact assembly as set forth in claim 6
wherein said securing section is C-shaped.

Description

ELECTRICAL CONTAC-r ASSEMBLY
This inverltiorl relates to electrical connectors and more particularly to
an electrical contact assembly for use in electrical connectors,
A known type of electrical contacts are those that are formed as
screw machine parts from bar stock. The bar stock from which these
electrical contacts are machtned has to be hard enough to enable them to
be subject to screw machine operations which can present problems when
electrical conductors are crimped thereto due to the wire barrels breaking.
These entire contacts are evenly gokJ plated thereover because they cannot
be selectively gold plated. The insertion force when a pin is ins~rted
thereinto is quite high.
Another type of known electrical contact assembly includes a screw
machine wire barrel onto which is crimped a telescoped receptacle and
hood. This type of contact can be selectively plated but a major draw~ack
is aligning the receptacle and hood and sirnultaneously crimping thern c~nto
the wire barrel as properly aligned and concentric ~ernbers. The wire
barrel is a screw machine part and, due to its configura~ion, cannot be
readily cold formed. The wire barrel would also be subject to breakage
when crirnped onto an electrical c~nductor because of the hardness of the
metal if not subjected to annealing. The insertion force is not believed to



.


be too low. Crimping of the receptacle onto the wire barrel does
not provide a good mechanical and electrical connection and
limits the diameter of the receptac]e. The hood contains no
beveled lead in surface for the pin.
According to the present invention, an elec-trical contact
assembly comprises a wire barrel onto which an electrical conduc-
tor is connected along with a receptacle contact member covered
by a hood member. A C~shaped section of the receptacle is fric-
tional]y secured in a bore of the wire barrel with the hood mem-

ber surrounding the receptacle and being crimped onto the wire
barrel. The hood has a beveled lead-in entrance to facilitate
insertion of a pin contact member into electrical connection with
the receptacle contact member at a substantially low insertion
force.
More broadly, the present invention provides an elec-
trical conLact assembly comprising: a wire barrel member formed
as a screw machine member or a cold-formed member and having a
rearward section to be terminated to a conductor and bore means
extending inwardly from a front end; and an electrical contact
member stamped and formed and having a contact section and a
securing sectionl said securing section being frictionally dis-
posed in said bore means thereby being mechanically secured there~
in in electrical engagement therewith.
The invention will now be described in greater detail
with reference to the accompanying drawings, in which:
@ FIGURE 1 is a perspective and exploded view of an elec-
- trical contact assembly.

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FIGURE 2 is a perspective view of an assembled electrical
contact assembly with an electrical pin contact exploded there-
from.
FIGURE 3 is a cross-sectional view of the assembled
electrical contact assembly.
FIGURE 4 is a cross-sectional view taken along line 4-4
of Figure 1.
FIGURE 5 is a cross-sectional view -taken along line 5-5
of Figure 3.
FIGURE 6 is a perspective view showing an electrical con-
nector i.n which the electrical contact assemblies are moun-ted.
FIGURE 7 is a cross-sectional view showing the electrical
contact assembly secured in an opening of the electrical connec-
tor.
Figures 1 through 5 illustrate the electrical con-tact
assembly 10 of the present invention with Figure 6 showing an
electrical connector EC in




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lL ~L4~ 9'~



which th~ electrical contact assemblies are secured for matable connection
with a sirnilar electrical connector ~not shown). Electrical contact assembly
10 includes a wirc barrel 12, a receptaclc contact ~-nember 14, anrl a hoocl
member 16.
Wire barrel 12 can be a screw machine part or it can be mac~e in
accordance with cold-Forming techniques in accordance with conventional
practices. if wire barrel 12 is made as a screw machine part, copper alloy
material is used, whereas if it is formed in accordance with cold-Forming
techniques, soft copper is used. It is preferable that soft copper be used
50 that wire barrel 12 can be cold-formed and it can be readily crimped
onto electrical conductor i 8 .
Wire barrel 12 is provided with a bore 20 in which electrical
conductor 18 is disposeci for electrical connection therewit~1. A sight hole
22 is located in wire barrel 12 to make certain that electrical conductor 18
has been properiy positioned within bore 20 prior to it being connected
thereto. An annular shoulder 24 is located adjacent the front end of wire
barrel 12 next to annular recess 26. A bore 28 extends inwardly from the
front end of wire barrel 12.
F~eceptacle contact member 1 l1 is a stamped and formed rnember that is
preferably stamped from beryllium copper and includes a C-shaped section
30 which frictionally engages bore 2B of wire barrel 12 to form an excellent
mechanical and electrical connection therewith thereby securing contact
member 14 therewithin. The resilient characteristics of C-shaped section
30 adds to the retention characteristics of C-shaped section 30 in bore 28.
Tapered channel-shaped section 32 extends between C-shaped section 30
and cylindrical section 34 and has arcuate-shaped contact-engaging




~.


members 36 extending outwarclly therefrom which taper towarcls each other
toward the front ends thereof. Contact rnember 14 is selectively plated in
the elect~ ;cai colltact area only on the inside sur faces of contact-engaginy
members 36 with a heavy ~old plating, ar~d the rest of the contact mernber
is flash plated. The selective gold plating can be done on the material
before stamping and forminy oF contact member 14 takes place.
~ lood member 16 is a stainless steel cylindrical member which has its
inner end crimped into annular recess 26, whereas its front encl has a
beveled surface 3B for Facilitating insertion of pin contact member 40 into
electrical contact with receptacle contact member 14. Hood member 16
protects contact member 14 and prevents spring contact-engaging members
36 from being overstressed.
The electrical contact assembly of the present invention has a low
insertion force because receptacle contact member 14 is a stamped ancl
formed part. This is a significant factor when a large number of
receptacle contact members are to be electrically connected with pin contact
members. Another important factor is the saving that takes place on
selective ~old plating because only heavy gold plating takes place on the
internal surfaces of contact-en~aging members 36 whereas the rest of
contact member 14 and wire barrei 12 are flash plated.
Figure 7 illustrates electrical contact assembly 10 secured in a
passageway 42 in dielectric mounting block 44 of electrical connector EC by
means of lances 46 of clip member 48 engaging shoulder 24 to prevent
wlthdrawal of contact assembly 10. Shoulder 24 is limited in its inner
movement within passageway 42 by surface 50 interposed between the
larger and smaller diameter sections of passageway 42. Another dielectric



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block 52 abuts acJainst bloclc LILI and has a passa~eway 51~ ~xtendincJ
therelhrouqh and In which part of the wire barrel of the contact assembly
is clisposed ancl alony which part o~ electrical conductor 18 exter-cis; .he
diameter of passageway 5LI at the intersection between passageways 42 and
54 is smaller in diameter than passayeway 42 to rnaintain clip rnember 44 in
passacJeway 4~. ~\n epoxy material or the like can be placed in
passageway 54 to seal the wire barrel and its termination to conductor 18.