Note: Descriptions are shown in the official language in which they were submitted.
1
PATENT
Attorney Docket
No. 2sh93-10227
10
~.NGhEIJ ELECTR2C~lL COIdI~IEC'fOit
Field of the Invention
This invention relates to an electrical
connector for terminating an electrical cable having
one or more conductors, and is particularly useful for
a right angle connector plug in which the elongated
shaft is skewed at an angle to a threaded bushing and
the cable which extends therefrom. More specifically,
the invention relates to an improved electrical
connector, such as a shielded connector, which is
structurally strong and easily assembled during the
manufacturing c~perat~.on as well as by the end user.
Backqrr"ound of the Invention
The interconnection of variouJ electronic and
electrical systems typically requires that a cable
containing one or more conductors terminates in an
electrical connector which removably mates with a
receptacle. Examples of electrical connect~rs are
quarter-inch phone plugs having an elongated male shaft
which is plugged into a female jack having connectors
for mating engagement with surfaces on the shaft.
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Often it is desirable that 'the elongated shaft be at an
angle such as 90° to the threaded shield so that the
inserted plug does not protrude much beyond the jack
bearing panel. Hecause of their manner of use, right
angle connectors often have increased :dress caused by
insertion and removal forces as contra:aed with the
standard in-line configuration in which the elongated
shaft and the threaded shielded bushing and extending
cable are coaxial. They also are more prone to
breakage than an in-line connector.
Conventional right angle connectors are
typically formed by a housing formed from separate
pieces which are joined together. One of the pieces
may be integral to the elongated shaft. These separate
pieces may each contain a partial annular thread and -
when mated together hold the individual pieces.
However, such a structure is more liable to breakage,
forms a less effective shield, and the increased number
of parts are individually and collectively less
structurally sound than is desirable. also, the number
of pieces of the plug which must be assembled by the
end user after connection is made to a cable should be
minimized particularly to reduce labor costs in
industrial and commercial applications. Unfortunately,
these requirements often conflict with the need to form
a structurally secure right angle connector.
2~~~2~3
Summate of the Tnvention
In accordance with the present invention, a
novel angled electrical connector is disclosed that is
mechanically strong, easily assembled a:nd minimizes the
number of parts which the end user needs to assemble
after connecting a cable to the connector. The cap
housing is substantially more solid than has been
typical in the prior art, and is structurally more
sound and forms a better shield. The end user needs to
join only one piece after connecting a cable to the
connector terminals;'as contrasted with three or more
pieces in many right angle connectors.
The present electrical connector is
particularly adapted to form a shielded plug, such as a
quarter-inch audio phone plug or the like. However,
the improved connector is useful whether or not the
plug is to be shielded, and reduces the forces which
cause breakage and difficulty in assembly. The
connector is easily assembled during the manufacturing
process and yet results in an'improved structure.
Hrief Description of the Drawings
Fig. 1 is a perspective view of a right angle
connector according to 'the present invention;
Fig. 2 is a partially exploded perspective
view of the connector of Fig. l;
4 ~oo~~o~
Fig. 3 is a partial sectional elevation taken
along lines 3-3 of Fig. 2;
Fig. 4 is a side elevational, view of a prior
art type of right angle connector;
Fig. 5 is a partially expladed perspective
view of the prior art connector of Fig. 4; and
Fig. 6 is a side elevational view of another
embodiment of prior art connector.
Description of the Preferred Embodiment
Figures.l-3 illustrate a novel electrical
connector embodied in a right angle phone plug which is
used to connect an electrical cable to a jack or
receptacle of standard design. Figs. 4-6 illustrate
right angle phone plugs which are typical in the prior
art. All such electrical connectors typically include
an elongated connector assembly 20 which extends from a
shell or cap assembly 22 which contains therein at
least one terminal which can be soldered to an
~LO electrical conductor of a cable (not illustrated). The
cable may be a shielded cable in which a center wire
conductor extends through a surrounding shield which is
to be connected to the cap assembly 22, or
alternatively, the cable could contain a plurality of
electrical conductors.
The elongated connector assembly 20 has a
terminating tip end 24 with a decent groove 25 spaced
2~~~'~~~
from the tip end which forms one electrical contact
which mates with a contact in the receiving jack. A
decent spring on the jack engages the groove 25 as i.s
conventional. Adjacent the tip end 24 is an annular
5 spacer or insulator 26 which electrically isolates the
tip from an annular hollow outer shaft 28 which forms a
second electrical contact surface. The' receptacle
jack, as is well known, includes contacts which engage
the shaft 28 in order to electrically connect the
plug to circuitry to which the receptacle jack is
attached. ,.
While a right angle audio connector of the
shielded type is illustrated, in which the contact tip
24 is connected to a center wire of a shielded cable,
and the surrounding shaft 28 and cap assembly 22 are
formed of metal and are electrically connected to the
shield of the cable, other types of electrical con-
nec~tors are suitable for use with the invention. Fox
example, the elongated connector assembly 20 may have
additional electrical contact surfaces separated by
additional insulators in order to form a connector for
a multiple wire cable.
In both the novel connector of Figs. 1-3 and
the prior art embodiments of Figs 4°6, the cap assembly
22 is threaded onto a metal annular cover or bushing
30. The bushing 30 is a hollow cylindrical shape
having interior threads 31 (see Fig. 5) adjacent c>ne
6 ;~ .
open end thereof. A circular aperture 33 is located at
the other end for the cable to extend into the bushing
30. Such a threaded bushing 30 may be identical to 'the
form used with an in-line connector. This. provides
economies of scale in the manufacturing process as well
as bushing parts which are interchangeable for a family
of in-line and right angle connectors.
In typical prior art connectors such as seen
in Figs. 4-5 and Fig. 6, the cap assembly 22 is often
l0 formed of two parts or halves, the front of which is
joined to or may be an integral part of the elongated
connector assembly 20. A rear half 32 mates to the
front half and may be connected thexeto in a variety of
manners. In the connector of Figs. 4-5, the front half
and the rear half each form about one half of an
exterior threaded cylinder. wizen abutted together, the
external threads form a complete cylinder which is held
together by the bushing 30 when threaded onto the
abutting pieces. In the type of prior art connector
shown in Fig. 6, the rear cover 32 is secured to the
front cover by a pair of screws 3~. Typically, the
connector of Fig. 6 does not form as good a shield'as
the other connectors but it is more inexrensive to
manufacture. In addition, the screws 34 or other
fasteners can be last and are more labor .intensive for
the end user to assemble together after the cable has
been secured to the terminals located inside the cover.
2~9~~~f
The right angle connector of Fags. 1-3 and
the prior art right angle connector of Figs. 4-5 each
include a long terminal 40 having a clamp or crimp end
42 which may be connected to the shield conductor of
the cable. The center wire of the cable is connected
to a short terminal 44 which mechanically and
electrically connects to an inner shaft 46 which
extends within the hollow outer shaft 28 to the front
terminal tip 24. The inner shaft 46 is of reduced
diameter and electrically isolated from the outer
surrounding shaft ,2.8'and extends down the hollow center
thereof into engagement with the tip end 24 and may be
formed as an integral part of the tip 24. The opposite
end of the inner shaft 46 is staked to the short
terminal 44 or is otherwise in contact to mechanically
and electrically join them together. A pair of --
insulating ribbons 48, seen only in Fig. 5, may be used
if desired to aid in electrically isolating the
terminal 44 and the center wire of the cable when
soldered thereto from the surrounding metal cap
assembly 22. The electrical connectors, to the extent
described above, are generally conventional and may be
varied as is known.
The aspects which are novel with respect to
the prior art and further details of the construction
will now be explained. The elongated connector
assembly 20 of Figs. 1-3 includes an outer shaft 28
a
2~9~2~~
that is integral with the shell assembly or cap 22. A
cylindrical aperture extends through the entire outer
shaft 28 to create the hollow interior through which
the inner shaft 46 extends in spaced rs:lationship to
the outer shaft 28.
The long terminal 40 is forir~ed of a metal lug
and includes a body portion 78, a neck portion 76 and a
clamp or crimped end 42 near the neck 76. The body 78
includes at least two surfaces. One surface of the
body 78 is of a shape to fit smoothly against the inner
surface of the shell assembly or cap 22. The contact
between the surface of terminal 40 and the shell
assembly or cap 22 provides an electrical contact.
Another surface of the body 78 is of a shape so that it
fits smoothly against the elongated guide recess 64 of
the insulated sleeve 60. The neck 76 is of a.reduced
size compared to the body 78. This allows the
elongated guide recess 64 'to pass easily over the neck
76 to make assembly easier. The neck 76 may be bent at
2'0 a slight angle towards the axis of the shell assembly
or cap 22 to position the clamp or crimp end 42 closer
to such axis. The lung terminal 40 includes a tab 70
which is bent at a right angle to the la~gitudinal ex-
test of the terminal and towards the connector assembly
20. Centered within the tab 70 is a circular aperture
74.
The short terminal 44 is formed of a lug
having a metal lug hole 90 for soldering to the center
wire of the cable, and at the opposite end of the lug a
circular aperture 92 of a slightly larger diameter than
the diameter of the neck 52 of the bushing 50. The
short terminal 44 is of a size and shape so that its.
edges 43 fit snugly within'the pair of slots 66 of the
insulating sleeve 60.
The insulating sleeve 60 is formed of a
nonconducting material in the shape of an elongated
partial cylinder having an open slot parallel with the
longitudinal extent of the cylinder. Opposite the long
slot is an elongated guide recess 64 to guide, support
and position the long terminal 40. The insulating
sleeve 60 also contains a pair of slots 66 extending
along the open slot of the cylinder 60 to form a second
guide support to guide, position and support the short
terminal 44 when slid into the pair of slots 66. The
insulating sleeve 60 is of a size and shape to snugly
fit in the interior of the shell assembly or cap 22 and
the pair of slots 66 are located inwardly from the edge
of the sleeve to maintain 'the short terminal 44 spaced
from and thereby electrically isolated with respect to
the metal cap 22, the long terminal 40 and the metal
conducting bushing 30 when it is serewed onto the shell
cap 22. The open slot of the insulating sleeve 60
creates a space 62 which accepts a mounting bushing 50.
~0~~3)
The mounting bushing 50 has a neck portion 52
and a shoulder portion (not shown). Tree bushing 50 may
be formed of an electrically conductive material. The
diameter of the neck portion is slightly smaller than
5 the aperture 92 in the short terminal 44 and extends
into the aperture 92 such that the shoulders (not
shown) of the bushing 50 abut the portion of the short
terminal 44 surrounding the aperture 92. The body 56
of the bushing 50 is of a size and shape to snugly fit
10 in the open space 62 in the insulating sleeve 60. The
neck 52 of the bushing 50 includes a receptacle (not
shown) of a diameter just slightly smaller than the
diameter of the neck portion 47 of the inner shaft 46.
This receptacle~may pass through both the neck 52 and
the body 56.
The shell assembly or cap 22 consists of an --
upper hollow housing 100 of generally cube shape.
Defining the generally cube shape is a rear wall 110
which is opposite to the front extending elongated
shaft 28, and side walls 112.' The interior of the
hollow housing 100 is generally box-like, in that it
surrounds and generally encloses a space. While the
exterior side walls are illustrated as flat, they may
be arcuate. Likewise, the interior surface may be
flat, arcuate or other shapes, all of. which are
intended to be covered by the phrase box-like. The
shell assembly o.r cap 22 may be made of an electrAcally
11
conductive material such as metal. The side walls 112
surround and define an annular side opening 108 that is
generally normal to the elongated shaft 28. Integrally
formed therewith is a lower generally cylindrical
member 102 containing exterior threads 104 which mate
with the interior threads located in the hollow bushing
30. Thus, the rear wall 110 and side walls 112 are
integrally formed of solid metal to form an electrical
shield surrounding the box-like interior with the
l0 shield being open at the side annular member 102 which
will mate with th~ metal bushing 30 to form the finally
assembled right angle connector.
On the interior of the shell cap 22, opposite
the opening 108, extends a protrusion 106, see Fig. 3,
of generally cylindrical shape and of the same or . _
slightly smaller diameter as the circular aperture 74
in the tab 70 on the long terminal 40. The protrusion
106 serves tc~ secure and key together the long terminal
40 to the cap 22, as will appear.
The elongated connector assembly 20 includes
an insulating collar 120 in the shape of a hollow
tubular shaft which is placed over the inner shaft 46.
The internal diameter of this insulating collar 120 is
slightly larger than the diameter of the inner shaft
46. The outer diameter of this insulating collar 120
is less than that of the inner diameter of the outer
shaft 28. The length of the insulating collar 120 is
12 ~~~
sufficiently long to prevent electrical contact between
the inner shaft 46 and the outer shaft: 28. The
insulating ring 26 is formed of a non--conducting
material in the shape of a donut and is placed around
the inner shaft 46 near the tip 24. ':Che insulating
ring 26 ensures that no physical or electrical contact
is made between the tip 24 and the outer shaft 28.
During assembly by the manufacturer of the
plug, the long terminal 40 is placed inside the hollow
cap 22 with the aperture 74 being placed over the
protrusion 106 and then staked thereto. Next, the
insulating sleeve 60 is placed in the cap 22 so that
the guide recess 64 in the insulating sleeve 60 fits
smoothly against one surface of the long terminal 40.
Meanwhile, the neck portion 52 of the mounting bushing
50 is planed in the aperture 92 in the short terminal
44. The shoulder portion (nat shown) of the bushing 50
abuts the portion of the short terminal 44 surrounding
the aperture 92. Then, the combination of the short
terminal 44 and the bushing 50 is placed within the
insulating sleeve so that the edges of the short
terminal 44 fits snugly within the pair of slots 66 and
the assembly is slid into the groove until the bushing
50 is fully within the cap 22. The center of the
aperture 02 of the short terminal 44 lies along the
center longitudinal axis of the outer shaft 28.
13
The elongated connector assembly 20 is now
completed and finally assembled into the cap 22. The
insulating ring 26 is placed around tha inner shaft 46
near the tip 24. The insulating collar 120 is placed
over the inner shaft 46 to at least partially surround
the inner shaft 46. The inner shaft 46, with the
insulating ring 26 and the insulating collar 120, is
then placed through the outer shaft 28 along the
longitudinal axis of the outer shaft 28. The neck
portion 47 of the inner shaft 46 is positioned through
the aperture 92 of the short~terminal 44 and into the
mating receptacle (not shown) in the neck 52 of the
bushing 50 to secure together the inner shaft 46 and
the bushing 50 with the short terminal 44 being
sandwiched therebetween and connected to both. The
inner shaft 46 is thus press-fit into the bushing 50.
The rear wall 110 of the shell cap provides a
firm and unyielding support for the press-fit operation
through the intermediaries of the long terminal 40 and
insulating sleeve 60, the mounting bushing 50 and the
short terminal 44. Once the inner shaft 46, the
bushing 50 and the short terminal 44 are secured
together, the shoulder 49 of the inner shaft 46 abuts
the front of the short terminal 44, and the shoulder
(not shown) of the bushing 50 abuts the rear of the
short terminal 44. The short terminal 44 is thus in
electrical contact with the inner shaft 46.
14
Preferably, the bushing 50 is made of metal
or other electrically conductive material, so that the
bushing 50 supplies a greater surface area for
electrically connecting the inner shaft 46 to the short
terminal 44. The sleeve 60 and bushing 50 thus form a
mounting device to support and prevent the end of the
short terminal 44 from moving rearwardly toward rear
wall 110 as the connector neck 47 is press fit
rearwardly into final engagement with the short
l0 terminal 44.
After assembly by the manufacturer, the
customer or end user is in effect supplied with a two--
piece connector consisting of the assembled shell
assembly 22, and the separate threaded bushing cover
30. When the customer desires to use the connector,
the cable is placed through hole 33 of the bushing
cover 30 and the center wire of the cable is soldered
within aperture 90 of the short terminal 44. The outer
shield may be crimped by the clamp 42 or otherwise
soldered or connected to the long terminal 40. The
bushing cover 30 is then screwed onto the exterior
threads 104 which serves as an interconnection surface
until the top annular rim 114 of the bushing cover 30
abuts the annular seat 111 of the upper housing 100.
Since the bushing 3U as well as the shell assembly or
cap 22 and outer shaft 28 are all foraned of conductive
metal, a good shield is formed for the inner wire of
15 .~y,
the cable once the bushing 30 is tightly screwed
against the bottom seat surfaces of the joined shaft
assembly.
The integral shell assembly 22 and outer
shaft 28 is substantially more solid than prior cap
housing units. The threads 104 extend completely
around the circumference of the lower annular member
102 to form a complete and uninterrupted cylinder,
unlike the typical prior art connectors which have
interruptions in the threaded interconnection member.
The structure created is fairly rigid arid is stronger
than the typical prior art devices. The strength of
the integral shaft connector and cap housing assembly
helps to reduce breakage. The part count of pieces for
final assembly by the end user or customer has been
reduced to two, namsly,~the assembled cap and the
bushing cover 30. Also, the novel shell assembly 22 is
more solid and forms a better shield than prior art
caps 22 as seen in Figs. 4-6 in which a split occurs in
the top of the cap caused by separate pieces or halves
which must be mated together.
While the connector has been shown for a
typical shielded audio plug having a pair of contacts
24 and 28 along an elongated shaft, it will be
appreciated that numerous variations can be made. The
electrical conductor can be used with or without a
shielded cable as desired. The connector can be made
16
in male or female form and for cables using one or
multiple conductors. The bushing 50 and short terminal
44 could be an integral unit, further reducing the
number of components required to assemble the
connector. Other changes are intended to be within the
spirit of the invention and can be made, by one skilled
in the art.
