Background of the Present Invention
[0001] This application describes and claims improvements over the inventions shown in my
previously issued United States patent No.
6,017,237, as well as Patents No.
5,996,224 and
6,105,229. The product patented there is a male type RJ45 connector, into which eight wires
from a cable are inserted, and associated crimping and shearing tool. When the connector
housing is crimped to secure the internal position of the wires, its internally contained
electrical contact blades also assume the positions in which they will matingly engage
the blades of corresponding contacts in the receptacle of an associated female RJ45
connector. For more than the past decade the eight-wire connector system disclosed
the referenced patents has been sold under my trademark EZ-RJ45 and used in ethernet
cable systems throughout the world. The uniqueness and novelty of these items has
not been challenged.
[0002] One important feature of the inventions shown in those patents is that the wires
are arranged inside the connector in such a way as to minimize interference or cross-talk
between data streams being transmitted on respective wire pairs. Another important
feature is the method in which color-coded wires inserted into the connector are allowed
to protrude out from its front end so that a technician may view the color coded wires
to verify their correct relative positions before shearing off their protruding ends.
A further feature of those inventions is the arrangement of the connector assembly
and its associated crimping and shearing tool such that the driven engagement of metallic
contacts into the wires inside the connector housing, and the shearing and cutting
off of the protruding wire ends, is done concurrently with the crimping of the plastic
connector to secure the wires in their places inside the connector.
[0003] As electrical components for high-speed data transmission are made smaller and smaller,
the data rates, packets, frequencies, and speed increase, and the corresponding wires
get larger and larger, it has become necessary to establish rigorous standards to
ensure their proper performance. Precise configurations and dimensions are required
by FCC regulations and other industry standards. A connector housing must be made
of a moldable injected material which is sufficiently moldable and deformable, such
as GE Lexan material, to capture and retain the wires inside it. At the same time,
the housing must have sufficient rigidity to reliably support the wires and their
associated contact blades in precisely correct positions, in order to mate with associated
contact elements in the receptacle of a female RJ45 connector. A further requirement
is that the moldable material utilized must meet a fire safety standard of the Underwriters
Laboratory and other international physical, electrical, quality and performance testing
standards.
[0004] Drawings of said previous patents show many important details of the EZ-RJ45 connector
as it has been and is presently being sold, those figures being identical in all three
of said three prior patents. For convenient reference, certain figures of said prior
patents are reproduced here as follows:
This Application |
Patent No. 6,017,237 |
Figure 1 |
Figure 8 |
Figure 2 |
Figure 9 |
Figure 3 |
Figure 5 |
Figure 4 |
Figure 6 |
There are also other important details shown in drawings of said prior patent that
are not fully replicated here, but understood. A more detailed description of the
prior art figures may therefore be gathered from the corresponding prior art document.
[0005] Connector 20 as shown in Fig. 5,6,8, and 9 of said prior patents (reproduced here
as Fig. 1-4) has an elongated hollow plastic housing 22. Insulated wires 16 enter
its open rearward end 24 and extend in guided pathways inside and through the housing.
Within the housing metal contact plates 36 having sharpened lower ends are poised
to pierce the insulation of and make firm electrical contact with corresponding wires.
The upper jaw 50 of an associated crimping and shearing tool has a downward protrusion
56 that will drive the metal contact plates 36 down into the correct position for
their forward edges to matingly engage corresponding contacts, not shown, in the receptacle
of the female RJ45 connector. The ends of wires 16 will not engage any contacts in
female receptacle.
[0006] As shown in Fig. 4 of this application [Fig. 6 of said prior patents] the crimping
and shearing tool has a lower jaw 70 which provides support underneath the housing
22 during a crimping and shearing operation. Figs. 1 and 2 of this application show
a control tab 30 which extends lengthwise underneath the housing 22. The forward end
of control tab 30 must meet shape and dimension standards prescribed by FCC standards
in order to correctly position the connector within the receptacle of a female connector
(not shown). The outer end portion of the control tab 30 also provides a small anvil
42 at the forward end of housing 22 against which six of the protruding wire ends
are sheared and cut when the crimping and shearing tool 50 is pressed downward.
[0007] In the EZ-RJ45 as shown in said previous patents the front end wall of housing 22
is largely closed but has openings 42 for the eight wires to protrude. There are also
slots or grooves in the front end wall that are partially occupied by the contact
blades 36, but the lateral edges of the blades 36 at the forward end of the housing
do not extend to the front face of the housing. Instead, they are recessed back from
the front end surface. This is necessary to allow the contact blades of a female receptacle
(not shown) to be guided into those slots or grooves for making face-to-face contact
with the lateral edges of contact blades 36. The mating contacts of the female receptacle
(not shown) are protruding contact blades which will enter those slots or grooves
to complete the electrical circuitry of the connector. The bared ends of wires 16
after they are cut do not engage any contacts in the female connector.
[0008] When tool 50, 70, is actuated for the crimping and shearing operation its cutting
blade 60 wipes the front end of housing 22. In the EZ-RJ45 connector as shown in the
prior patents, six of the eight protruding wires 16 -- wires numbers 2 through 7 --
are freely floating over the anvil 42 and are reliably cut off in concert by the crimping
and shearing tool 50, 70. The reason for this is that the connector control tab 30
must have exactly correct dimensions in order to precisely fit within a receptacle
whose shape and dimensions are prescribed by an FCC or industry standard. The control
tab 30 is wide enough to provide a supporting anvil only for wires 2-7. It has therefore
been a practice in the field for the technicians using the EZ-RJ45 system to finish
cutting off the ends of wires 1 and 8 by hand, after the connector housing has been
crimped and the other wires have already been cut off. The wires used in the EZ-RJ45
connector are typically of the AWG size 24 in CAT 5 cable, with a proven data transmission
rate per respective standards.
[0009] As shown in the prior patents, openings 44 through which the eight wires 16 will
protrude are in a lower portion of the forward end face of housing 20. The slots or
grooves for the contact blades are in the upper area of the front end wall of connector
housing 20, and there is a vertical separation between the horizontal row of openings
44 for the wires and the slots or grooves for the contact blades 36.
[0011] It is necessary for the contact blades, not shown, of a female RJ45 connector to
precisely mate with the forward edges of contact blades 36. The field experience and
complaints with the EZ-RJ45 connector system have shown a need for improved performance.
The operation of the shearing and crimping tool 50, 70, often tends to cause a distortion
in the plastic housing 20, so that the wires and contacts are not maintained precisely
in their desired dimensionally stable positions. There are several different forces
that contribute to this result:
- 1. sliding contact force overcoming friction for seating blades 36;
- 2. insulation displacement force IDC. This is the force it takes to push the gold
connector contact blades 36 into the wire insulation plastic coating and mate with
the copper wires.
- 3. cut wire force - the shearing force needed to cut the wires 2-7;
- 4. any dullness of the cutting blade exacerbates the problem.
- 5. since the blade 60 as shown in my prior patents is free-floating, any misalignment
of the blade also exacerbates the problem.
[0012] All of these forces tend to push, twist, and deform the connector housing in an undesired
manner. This may lead to an FCC non-compliant connector that has to be discarded,
causing loss of time and money.
[0013] Since the presently available products requires hand cutting of wires 1 and 8, it
would also be desirable to have all eight of the wires cut and sheared by the crimping
and shearing tool, to avoid an extra hand working step by the technician.
Summary of the Present Invention
[0014] The present invention is provided by appended claims 1, 9, and 10. Beneficial embodiments
are provided in the dependent claims. Accordingly, a housing of an electrical connector
is provided, comprising an integrally thickened front end wall portion that is adapted
to mechanically support the housing while the thickened end wall portion is being
sheared off.
[0015] The housing as described above may have an hollow elongate shape and the integrally
thickened front end wall portion has a generally continuous forward end wall with
upper and lower surface areas, and the lowermost surface area of the wall having an
integrally thickened outer portion which is adapted to be sheared off to make the
connector operable.
[0016] The housing as described above may comprise the thickened front end wall portion
having at least one opening through which wires placed inside the housing may project
outward beyond its forward end wall.
[0017] The housing as described above may comprise the upper surface of the forward end
wall having a plurality of slots formed therein for receiving contact blades of a
mating connector.
[0018] The housing as described above may comprise the upper surface of the forward end
wall having a plurality of slots formed therein for receiving contact blades of a
mating connector.
[0019] The housing as described above may comprise the at least one opening including an
upper row of openings and a lower row of openings, and the thickened end wall portion
surrounds the at least one opening.
[0020] The housing as described above may comprise the upper row of openings and the lower
row of openings merging into one another.
[0021] The housing as described above may comprise the thickened end wall portion having
a groove formed therein for guiding the movement of a cutting blade to shear off the
thickened end wall portion.
[0022] In one embodiment, the present invention also provide a method of forming an electrical
connector comprising providing a housing as described above, forming at least one
opening through the thickened front end wall portion, feeding a plurality of wires
respectively through the at least one opening, and then shearing off the thickened
end wall portion together with the wires contained therein.
[0023] In one embodiment, the present invention also provide a method of forming an electrical
connector comprising a housing as described above, feeding a plurality of wires respectively
through the at least one opening, and then shearing off the thickened end wall portion
together with the wires contained therein.
[0024] The method as described above may comprise that the at least one opening is formed
in an upper horizontal row and a lower horizontal row, the wires in the upper row
of openings are sheared off first, and then the wires in the lower row are sheared
off.
[0025] The first main concept of the present invention is using wires having thicker insulation,
of AWG size 23, and keeping each twisted pair in its twisted state as close as possible
to the pair of metal contacts that will conductively engage its respective wires,
in order to improve the electrical performance and data transmission rate of the connector.
[0026] A second main concept of the present invention is to provide a thickened front end
wall (herein also referred to as External Load Bar or Stiffener). The outer dimensions
of the connector housing must be limited to comply with legal and industry standards,
and the larger wires necessarily require a reduction in the amount of plastic material
forming the connector housing. The External Load Bar (or Stiffener) mechanically supports
both the connector housing and the wires it contains, and is then sheared off along
with the protruding wire ends in order to allow the male connector to properly mate
with an associated female connector.
[0027] A third main feature of the present invention is a method which not only allows the
outer ends of the protruding wire pairs to project from the front of the connector
for color comparison purposes, but also allows the wires to be pulled and tightened
in their still-twisted condition and brought as close as possible to their respectively
associated contact blades before being sheared off. This method helps to improve the
quality of electrical performance and to increase the data transmission rate.
[0028] According to the present invention, holes for the protruding wires, as well as slots
or grooves for the contact blades, are provided in the thickened front end wall in
generally the same way as shown in the prior parents. However, the thickened portion
of the front wall (External Load Bar), which does include the area where the horizontal
openings for the protruding wires are formed, does not include the slots or grooves
that will receive the contact blades of a female receptacle.
[0029] When the modified crimping and shearing tool of the present invention cuts off the
protruding ends of the wires it simultaneously shears off the unwanted thickness of
the front end wall (External Load Bar or Stiffener). The Stiffener or Load Bar is
formed integral with the forward end wall of the housing. Therefore, when the blade
acts to cut off the Stiffener or Load Bar, that Stiffener or Load Bar continues to
provide a stabilizing support for the front end wall of the housing until the action
of the cutting blade is fully completed and the Stiffener or Load Bar has become fully
severed from the connector housing.
[0030] With this thickened or stiffener portion of the front end wall, the housing 22 better
supports both the wires, and the slots or grooves for receiving the contacts blades,
before, during, and after the wires are cut off.
[0031] Thus in shearing off the exposed ends of the wires, now at the same time the thickened
or stiffener part of the end wall is cut off, still leaving a thin front end wall
for the connector housing that is sufficient to maintain the correct spatial locations
of both the wires 16 and the contact blades 36. The connector then fits correctly
within its allotted space in an associated female receptacle or terminal board.
[0032] In other words, by thickening the front end wall of housing 22, now the connector
is initially made too long to fit within its prescribed space in a receptacle or panel
board. But by cutting off the excess thickness of the front wall while the connector
housing is being crimped and the contacts 36 are being forced into their conductive
engagement with the associated wires 16, the connector housing length may be reduced
so that it does correctly fit, and also improves the end result of correctly terminating
the connector.
[0033] Horizontal guideways are provided inside the connector housing 22 to permit two horizontal
rows of four wires each, in a staggered relationship, to be inserted into and through
the connector. The holes or openings in the front end wall of housing 22 are then
in two separate rows, four in each row. Adjacent holes then tend to slightly overlap
or merge into each other.
[0034] Another and related feature of the present invention is modifying the crimping and
shearing tool so that it very positively cuts off all the protruding wire ends concurrent
with the crimping operation. This is accomplished by adding a pair of short posts
to the lateral ends of the lower jaw 70 of crimping tool 50, 70. These posts together
with the control tab 30 then provide an expanded and adequate anvil surface 42 for
cutting off all of the wire ends that are encased in plastic; first the four in the
upper horizontal row, and then the four in the lower horizontal row.
[0035] A still further feature of the present invention is that a set of guides is also
provided to control downward movement of the cutting blade, and a groove extending
laterally across the upper surface of the External Load Bar adjacent to the front
wall of the connector housing, to guide the edge of cutting blade 60 when the blade
is pushed down in its cutting action.
[0036] The objective of these improvements is to provide a connector that is suitable for
use with CAT 6, CAT 6A and other ethernet cable and future larger wires and standards,
in order to reliably operate at a data transmission rate of ten gigahertz and future
transmission rates and applications.
Brief Description of the Drawings
[0037]
Figs. 1 through 4 are provided as exact copies of certain figures in prior patents,
which is necessary in order to provide a proper basis for describing my present invention.
Fig. 5 is a front end elevation view of a modified connector housing and External
Load Bar, showing the empty connector not loaded with wires;
Fig. 6 is an elevational cross-section taken on Line 6 - 6 of Fig. 5 showing the empty
connector housing with the External Load Bar on its forward end wall;
Fig. 7 is a side elevational view of the connector housing loaded with wires;
Fig. 8 is a view like Fig. 7, but additionally with schematic indications showing
how the crimping and shearing operation, and the separation of the External Load Bar
with its encased wires, will be done;
Fig. 9 is a side elevational view showing the External Load Bar after it has been
separated from the connector housing, and still retains its accompanying load of the
insulated wires which still remain encased in it and protrude from it; and
Fig. 10 is a front end elevation of the loaded connector housing after the External
Load Bar has been shorn off, exposing the bare ends of the insulated wires.
DETAILED DESCRIPTION
[0038] As shown in Figs. 5 and 6, the modified connector housing 122 has a thickened Stiffener
100 (otherwise known as the External Load Bar) formed as an integral lower part of
its front end wall 128. A horizontal row of four upper holes 145 and a horizontal
row of four lower holes 144 are formed through the solid material of the Stiffener.
As best seen in Fig. 5, the holes of the rows are staggered, and tend to blend or
merge together. Stiffener 100 preferably has a flat bottom surface identified by numeral
104. During the shearing operation, stiffener 100 will be supported from that bottom
surface 104, which will in turn rest upon an anvil. Optionally, the stiffener 100
may also comprise one or more supporting ribs (not shown) extending from the bottom
surface 104 towards control tab 30 extending from the front portion of a bottom wall
124 of connector housing 122. There is a thin layer of plastic material underneath
the lower holes 144, which forms the bottom surface 104.
[0039] On the front wall of housing 122 as best seen in Fig. 5, there is an upper vertical
area 132, above the Stiffener 100, where the slots or grooves 130 for contact blades
36 are located. There are eight of these slots to accommodate the eight contact plates
36. The cross-section view of Fig. 6 shows one contact blade 36 occupying the corresponding
slot or groove 130.
[0040] As shown in Fig. 6, the bottom wall of connector housing 122 is designated 124 and
its bottom surface as 126. When the connector is loaded with wires, they will be in
suitable guideways extending the length of the hollow connector housing, and will
also extend through the holes 144, 145, and protrude outward from the front side of
the Stiffener 100.
[0041] Since Fig. 6 is a cross-section view, it shows one of the contact blades 36 occupying
a corresponding one of the slots 130.
[0042] As also indicated in Fig. 6, the plastic material of Stiffener 100 is formed integral
with front end wall 128 of housing 122. That is preferable, because when the Stiffener
100 and the encased wires it contains are sheared off, the Stiffener continues to
mechanically support the front end wall 128 until the shearing is fully complete.
[0043] As shown in Fig. 6, the upper surface of Stiffener 100 has a small groove 102 that
is immediately adjacent the flat upper face 132 of the connector housing. The purpose
of that groove is to guide the action of cutting blade 60 when the stiffener and wire
ends are to be sheared off.
[0044] Reference is now made to Fig. 7 which shows the connector housing when loaded with
insulated wires. Wires 16 are unsheathed from an incoming cable with a length sufficient
to protrude at least several inches of gripping length from the front side of Stiffener
100. This allows the technician to pull the wires tight before doing the crimping
and shearing operation. Tightness of the wires inside the connector housing improves
the electrical performance of the connector.
[0045] Fig. 8 reproduces the loaded housing of Fig. 7 on a smaller scale, to provide space
to schematically illustrate how the crimping and shearing will be done. A hand tool
300 above the housing drives arrows 301, 302, and 303 downward. Arrow 301 represents
the crimping of the plastic housing, in the manner shown in my prior patents. Arrow
302 represents the blade driver that drives all of the blades 36 into electrical engagement
with the corresponding contact blades. And arrow 303 represents the cutting blade
60 that will shear off both the Stiffener 100 and its encased wires. A block 42 shown
in the lower left corner of the drawing represents an anvil that supports the bottom
surface 104 of the Stiffener 100, and that the blade 60 will engage at the end of
its cutting stroke. The optional one or more supporting ribs (not shown) extending
from the bottom surface towards the control tab are preferably completely removed
from the plastic housing by the shearing process.
[0046] As shown in Fig. 9, the Stiffener 100 after separation from front wall 128 of the
housing still retains its load of insulated wires 16 protruding from its front side.
It is then no longer needed, and may be disposed of.
[0047] As shown in Fig. 10, removal of the Stiffener has left the bare front wall in which
the bared ends 146 of the insulated wires are clearly visible. The wire ends 146 do
not and must not protrude, or there would be a risk of electrical engagement with
the female connector. To accomplish the appropriate electrical function of the connector,
that must not be tolerated. Removal of the Stiffener brings the size and shape of
the housing back to the industry and FCC standard, so as to correctly mate with a
female RJ45 connector.
[0048] As described above, the modified connector housing of the present invention is made
with the Stiffener or External Load Bar as an integrally formed part of it. Four pairs
of insulated wires are inserted into and through the housing 122, and through the
upper and lower holes 144, 145, in the Stiffener. The manner of guiding the wire pairs
is such that one wire of each pair protrudes through an upper hole 145, and the other
wire of each pair protrudes through the adjacent lower hole 144.
[0049] Before shearing the Stiffener and encased wire ends the technician will check the
color coding of the wires to verify their correct locations. He then preferably stretches
each of the wire pairs by pulling its protruding ends. The purpose of that is to bring
each wire pair, inside the connector, as close as possible to the respectively associated
contact blades. This is essential to maximize the electrical performance of the connector.
[0050] The crimping and shearing tool 50, 70 may be modified, to provide two small posts
that extend the ends of anvil 42, so that all eight of the wires will be cut in a
single pass of the cutting blade 60. The Stiffener sits directly on the anvil, with
no space between its bottom surface and the anvil. There is a measurable thickness
of plastic material below the bottom row of holes. When the shearing takes place,
the blade 60 first cuts all of the wires in the upper row 145, and then all wires
in the lower row 144. After the shearing is done the Stiffener - which is now detached
from the front wall 128 - may be disposed of. Connector housing 122 is then moved
into mating engagement with an associated female receptacle, bringing the contact
prongs of the female receptacle into engagement with the contact blades 36. Performance
tests, if necessary or desired, may then be conducted.
[0051] Optional and preferred embodiments of the invention:
[0052] An electrical connector housing having an integrally thickened front end wall portion
that is adapted to mechanically support the housing while the thickened end wall portion
is being sheared off.
[0053] An electrical connector, comprising an elongated hollow housing having a generally
continuous forward end wall with upper and lower surface areas, and the lowermost
surface area of the wall having an integrally thickened outer portion which is adapted
to be sheared off to make the connector operable.
[0054] A connector as mentioned above, wherein the thickened wall portion has a plurality
of openings through which wires placed inside the housing may project outward beyond
its forward end wall.
[0055] A connector housing as mentioned above , wherein the upper surface of the forward
end wall has a plurality of slots formed therein for receiving contact blades of a
mating connector.
[0056] A connector housing as mentioned above , wherein the upper surface of the forward
end wall has a plurality of slots formed therein for receiving contact blades of a
mating connector.
[0057] A connector housing as mentioned above, wherein the openings include an upper row
of openings and a lower row of openings, and the thickened wall portion has a measurable
amount of plastic material beneath the lower row of openings.
[0058] A connector housing as mentioned above, wherein the thickened wall portion has a
groove formed therein for guiding the movement of a cutting blade to shear off the
thickened wall portion.
[0059] Method of using a hollow electrical connector housing having a front end wall with
an external integrally thickened wall portion, comprising the steps of;
forming a plurality of holes through the thickened wall portion;
feeding a plurality of wires through respectively corresponding holes; and
then shearing off the thickened wall portion together with the wires contained therein.
[0060] The method as mentioned above, wherein the holes are formed in an upper horizontal
row and a lower horizontal row, the wires in the upper row of holes are sheared off
first, and then the wires in the lower row are sheared off.
[0061] Electrical connector, comprising a housing with a forward end wall from which wires
are allowed to protrude before being sheared off, the method of supporting the wires
while they are being sheared off by providing openings in the forward end wall through
which the wires initially pass, and forming an integral protrusion on the forward
end wall with extensions of those openings through which the wires also pass before
both they and the protrusion are sheared off.
[0062] Although the invention was described in detail in order to comply with requirements
of the patent laws, it will be understood that the scope of my protection is to be
adjudged only in accordance with the appended claims.
Alternative Embodiments
[0063] Alternative embodiments of the present disclosure provide a housing (122) of an electrical
connector, comprising an integrally thickened front end wall portion (128) that is
adapted to mechanically support the housing (122) while the thickened end wall portion
(128) is being sheared off.
[0064] In one alternative embodiment, the housing (122) has an hollow elongate shape and
the integrally thickened front end wall portion (128) has a generally continuous forward
end wall with upper and lower surface areas, and the lowermost surface area of the
wall having an integrally thickened outer portion (100) which is adapted to be sheared
off to make the connector operable.
[0065] In one alternative embodiment, the thickened front end wall portion (128) has at
least one opening (144, 145) through which wires placed inside the housing (122) may
project outward beyond its forward end wall.
[0066] In one alternative embodiment, the upper surface of the forward end wall has a plurality
of slots formed therein for receiving contact blades of a mating connector.
[0067] In one alternative embodiment, the upper surface of the forward end wall has a plurality
of slots formed therein for receiving contact blades of a mating connector.
[0068] In one alternative embodiment, the at least one opening (144, 145) includes an upper
row of openings (145) and a lower row of openings (144), and the thickened end wall
portion (128) surrounds the at least one opening (144, 145).
[0069] In one alternative embodiment, the upper row of openings (145) and the lower row
of openings (144) merge into one another.
[0070] In one alternative embodiment, the thickened end wall portion (128) has a groove
(102) formed therein for guiding the movement of a cutting blade (60) to shear off
the thickened end wall portion (128).
[0071] Further alternative embodiments of the present disclosure provide a method of forming
an electrical connector, comprising providing a housing according to above alternative
embodiments; forming at least one opening (144, 145) through the thickened front end
wall portion (128); feeding a plurality of wires respectively through the at least
one opening (144, 145); and then shearing off the thickened end wall portion (128)
together with the wires contained therein.
[0072] Further alternative embodiments of the present disclosure provide a method of forming
an electrical connector, comprising providing a housing according to above alternative
embodiments; feeding a plurality of wires respectively through the at least one opening
(144, 145); and then shearing off the thickened end wall portion (128) together with
the wires contained therein.
[0073] In one alternative embodiment, the at least one opening (144, 145) is formed in an
upper horizontal row (145) and a lower horizontal row (144), the wires in the upper
row of openings are sheared off first, and then the wires in the lower row are sheared
off.
1. Electrical connector, comprising:
an elongated hollow housing having a generally continuous forward end wall with upper
and lower surface areas, the lowermost surface area having an integrally thickened
outer portion which is adapted to be sheared off to make the connector operable, and
wherein the thickened wall portion has a plurality of openings through which wires
placed inside the housing may project outward beyond its forward end wall.
2. A connector according to claim 1, wherein the upper surface of the forward end wall
has a plurality of slots formed therein for receiving contact blades of a mating connector.
3. A connector housing according to one of claims 1 and 2, wherein the openings include
an upper row of openings and a lower row of openings, and the thickened wall portion
has a measurable amount of plastic material beneath the lower row of openings.
4. Method of preparing an electrical connector, comprising the steps of:
selecting an elongated hollow plastic housing having an open rearward end and an essentially
continuous forward end wall, a lower portion of the forward surface of the forward
end wall being integrally thickened, and the forward end wall including the thickened
lower portion comprising a set of openings therethrough, the upper portion of the
forward end wall having slots for receiving contact blades of a mating connector;
inserting a plurality of wires into the open rearward end of the housing into and
through corresponding ones of the set of openings in the forward end wall so that
the plurality of wires project forwardly beyond the forward end wall; and
shearing off the thickened portion of the forward end wall and concurrently with it
the projecting ends of the wires flush with the then remaining forward end wall surface
of the housing.
5. The method according to claim 4, wherein two parallel rows of openings are formed
in the forward end wall, an upper row and a lower row.
6. The method according to claim 5, wherein the openings in the upper row are larger
than the openings in the lower row.
7. The method according to one of claims 4-5, wherein the wires are electrically insulated.
8. The method according to one of claims 4-7, wherein a plurality of slots are formed
in the upper surface of the front end wall for receiving the contact blades of a mating
connector, and wherein the plastic housing is mechanically supported while the thickened
wall portion and protruding wires are being sheared off, so as to preserve the dimensional
stability of the upper portion of the forward end wall and the slots therein.
9. The method according to claim 4, further comprising forcing metal contact plates into
conductive engagement with respective ones of the plurality of wires.
10. The method according to claim 9, wherein forcing metal contact plates into conductive
engagement with respective ones of the plurality of wires comprises forcing metal
contact plates through an insulation coating of respective ones of the plurality of
wires and into conductive engagement with respective ones of the plurality of wires
while shearing off the thickened portion of the forward end wall and the projecting
ends of the wires.
11. The method according to claim 10, further comprising crimping the connector housing
while forcing metal contact plates into conductive engagement with respective ones
of the plurality of wires and shearing off the thickened portion of the forward end
wall and the projecting ends of the wires.
12. Electrical connector, comprising:
an elongated hollow housing having a generally continuous forward end wall with upper
and lower surface areas, the upper surface of the forward end wall having a plurality
of slots formed therein for receiving contact blades of a mating connector, and the
lowermost surface area of the wall having an integrally thickened outer portion which
is adapted to be sheared off so as to avoid deforming the upper surface of the forward
end wall.
13. Electrical connector as in Claim 12, wherein a plurality of holes are formed in the
thickened lowermost surface of the wall.
14. Electrical connector as in Claim 13, wherein the holes are formed in two horizontal
rows, an upper row and a lower row.
15. Electrical connector as in Claim 14, wherein the holes in the upper row are of larger
diameter than those in the lower row.
16. Electrical connector as in Claim 14, wherein the holes in the two rows are in staggered
relationship.
17. Electrical connector as in Claim 14, wherein the holes of the two rows are partially
merged together.