Background of the Invention
[0001] Terminal connecting blocks or modules are widely used in the telecommunications industry
to interconnect equipment and distribution lines, particularly in signal switching
or distribution applications. Their primary function is the solderless connection
of two or more wires.
[0002] Apart from their primary function, connecting modules of the kind the present invention
is concerned with provide for a quick, mechanically secure and electrically sound
connection. In addition, they provide for relatively simple and fast disconnection,
as needed where frequent rewiring is necessary. Quick connection is provided by eliminating
as much pre- connection and post-connection conditioning as possible. Stripping, bending
or trimming operations should be unnecessary, such that connection may be accomplished
with few movements. Mechanically secure and electrically sound connections are provided
by interference, clamp or like connection methods in which the connection module exerts
a positive grip on an installed wire conductor.
[0003] To provide a connecting module having such qualities, it is known to utilize a metal
split cylinder having an axially extending narrow seam or slot. A wire is connected
to the cylinder by moving it laterally of its axis into the slot so that the edges
of the slot slice through the insulation and establish contact with the conductor
with a positive gripping force as provided by the resilience of the cylinder cross
section. It is also known to support a cylinder in an insulating housing of generally
cylindrical shape with a rectangular cross-section, in a coaxial orientation, to form
a connector module. The housing is slotted along diagonally opposite corners and the
cylinder aligned therein such that one corner slot is aligned with the wire receiving
slot in the cylinder. Installation of a wire is accomplished by laying it to extend
through the housing slots, over the cylinder, and using an impact tool to drive the
wire down into the split cylinder, which preferably includes a cutting edge opposite
the wire receiving slot to trim or sever the excess wire length. An installed wire
is thus shielded from others by the housing such that shorting and interference problems
are avoided. In actual practice, a plurality of housings are mounted to extend orthogonally
from a planar member to form a multiple connector terminal connecting panel. An example
of such a panel is disclosed in co-pending U.S. Patent Application Serial Number 321,107,
to Vachhani, filed Nov. 31, 1981, and entitled "Electrical Connector Module."
[0004] Although the Vachhani panel provides for the quick and secure solderless cross connection
of a large number of wires at a central location with relatively high density, it
does have certain disadvantages. For one, assembly of the panel requires that individual
modules be mounted one at a time, such that assembly is time consuming and correspondingly
expensive. For another, the diagonal orientation of the wire slots together with the
side by side orientation of the housings generally requires that wires be positioned
and installed one at a time, such that a technician must continually switch between
positioning and inserting operations. This has been recognized as time inefficient
in the consecutive installation of large numbers of wires. Another undesireable aspect
of the Vachhani module relates to stresses exerted on the split cylinder by the wire
insertion tool. It has been found that due to the impact operation of the tool and
the relatively pliable housing material used for the modules that the wire receiving
cylinder was susceptible to connection threatening deformation during installation
of a wire. In addition, the Vachhani tool needs to be oriented with respect to a housing
for proper operation, which has been also recognized as undesireable. Finàlly, the
tool includes moving parts and is thus relatively expensive.
Summary of the Invention
[0005] The present invention provides an electrical connector panel and a tool for installing
or inserting wires in the panel which alleviates or eliminates the above described
disadvantages of the Vachhani apparatus. According to one aspect of the invention
a plurality of metal split cylinders of the above described type are provided and
mounted in a non-conductive housing to form a connector module. The housing is formed
to support the split cylinders in a plurality of cylindrical subhousings formed in
two rows, with each of the subhousings including slots on diametrically opposed sides
with one of the subhousing slots coaxially extending with the slot in the split cylinder,
and with the subhousing slots aligned transversely to the rows. The subhousings in
each row are laterally spaced apart to form a plurality of inter subhousing slots
and the subhousings in different rows are laterally offset so that one slot of each
subhousing is aligned with one of the inter subhousing slots. According to this aspect
of the invention a plurality of wires to be installed may be laid side by side and
parallel in the subhousing slots in one series of operations, and installed in another
series of operations, eliminating the need to switch back and forth between wire placement
and insertion operations where two or more wires are to be installed in the panel
sequentially.
[0006] According to another aspect of the invention the module housing includes a snap mounting
arrangement comprising one or more flexible bridges and shoulders disposed on the
side of the housing and longitudinally spaced apart. The bridges include a bridge
member spaced apart from the side of the housing and supported on opposite ends so
that it may flex toward the housing when compressed. The panel member provided for
supporting the housing includes an aperature sized to receive the housing with the
aperature including one or more tabs positioned to engage the bridge or bridges and
compress them inwardly as the housing is slid into the aperature, and to engage a
transverse edge of the bridges when the housing is mounted. A shoulder is provided
to stop the housing in the mounting position such that the housing is snapped into
place and immovably retained by the shoulders on one side of the housing and the transverse
edge of the bridges of the other. Thus, the present invention provides for the mounting
of a plurality of connectors to a panel simultaneously, as opposed to mounting single
connector modules one at a time, thus resulting in substantial time savings in panel
assembly.
[0007] According to yet another aspect of the invention the housing is constructed of a
relatively rigid plastic non-conducting material, and a simple wire insertion or installation
tool with no moving parts is provided to insert wires. The wire insertion tool includes
a central post sized to fit inside the split cylinder and a cylindrical member coaxially
extending around the post and sized to fit around the outside perimeter of the cylinder
between the cylinder and the housing. A shoulder is provided on the tool and is axially
displaced from the tip, the shoulder being of sufficient radius to engage the end
transverse edges of a subhousing with the tip of the tool extending in and around
the split cylinder mounted therein. Thus, wires to be installed may be laid across
the top of the cylinder extending through the subhousing slots and pressed into the
cylinder with the tool, which by virtue is its cylindrical configuration does not
need to be oriented, and which does not include moving parts. Furthermore, the operation
of the tool provides that the subhousing absorbs certain stresses from the tool as
the wire is being inserted to avoid deformation of the split cylinder.
[0008] According to still another aspect of the invention the end portions of each subhousing
cylinder are funnel shaped to facilitate insertion of the tool into the ends of the
subhousings, and to guide the tool into proper axial orientation with the split cylinder.
In addition, at least one slot of each subhousing includes arcuate axially extending
lips on each side of the slot, with the width of the passageway formed between the
lips being slightly less than the diameter of a wire to be installed, so that the
lips provide a mechanical grip and strain relief for the wire during and after installation.
[0009] Thus, the present invention provides an electrical connector panel eliminating or
alleviating the problems above-discussed with respect to the Vachhani apparatus. More
specific details, aspects and salient features of the construction and operation of
the invention are set forth in the ensuing drawing and specification.
Brief Description of the Drawing
[0010]
FIGURE 1 is a perspective view of a connector module according to the present invention;
FIGURE 2 is a top plan view,of the electrical connector module according to the present
invention;
FIGURE 3 is a cross sectional view of the connector module according to the present
invention taken along the lines 3-3 of Figure 1;
FIGURE 4 is a cross sectional view of a portion of the connector module according
to the present invention taken along the lines 4-4 showing the installation tool according
to the present invention inserted therein; and
FIGURE 5 is a cutaway perspective view of the installation tool according to the present
invention; and
FIGURE 6 is a cross sectional view of the connector module of the present invention
taken along the lines 6-6 of FIGURE 3.
Detailed Description of the Invention
[0011] The electrical connector apparatus of the present invention is provided for use in
an access member such as the quick-cross connect panel or in a terminal block to electrically
connect various electrical lead wires or circuits with certain other electrical lead
wires or circuits. In actual practice, the lead wires may be part of a communication
circuit such as a telephone line or a data transmission circuit. Where the leads are
telephone lines, the electrical connector module of the present invention is utilized
to patch or cross-connect such lines to accommodate growth of telephone usage, changes
in telephone number, relocation of users, etc.
[0012] Referring to FIGS. 1 and 2 an electrical connector module according to the present
invention is illustrated, in perspective and plan views. Connector module 10 is mounted
in a relatively flat panel member 11, in an aperature 12, of generally the same cross-section
as connector module 10. Module 10 includes a housing 15 molded of a relatively rigid
non-conductive plastic. Housing 15 includes a plurality of generally cylindrical subhousings
20, extending on either side from panel member 11 (see FIG. 3), each of which supports
a centrally positioned split cylinder connector member 18. Each of subhousings 20
are formed to include funnel shaped end portions 17 as may be seen best with reference
to FIGS. 3 and 4, to facilitate entry and alignment of an insertion tool, as will
be described in more detail below. Although partially asymmetrical in certain detail,
the module is identical on each side of the panel member with respect to the function
and construction of the operative portions of subhousings 20.
[0013] With reference to FIGS. 3 and 4 it may be seen that connector member 18 includes
a first end 30 including a collar 31, a wire engaging slot 33 and a wire trimming
edge or blade 34. The other end of connector member 18 includes a pair of tine members
37 and 38 cut from the sidewalls of the cylinder, a wire engaging slot 39 and a further
trimming blade 40. Each end of connector member 18 further includes wire guide sections
41 and 42 narrowing toward the respective slots 33 and 39, and a transverse cut 35
structurally isolating the cross sectional resilience of the opposite ends.
[0014] To accomodate the mounting of a connector member 18 in the cylindrical subhousing
20, the housing' includes an annular retaining portion 50 extending inward from the
sidewall of subhousing 20 and having a radius slightly smaller than that of connector
member 18. A pair of diametrically opposed and longitudinally extending grooves 51
and 52, having a width slightly larger than that of tines 37 and 38 respectively,
are provided in retaining portion 50. The mounting of connector member 18 may thus
be accomplished by inserting the member tine-end first into the subhousing such that
tines 37 and 38 are compressed as they pass through the upper portion of retaining
portion 50, and snap into place in grooves 51 and 52. Connector member 18 is thus
axially retained in place by shoulder member 31 on one side of retaining portion 50
and by tines 37 and 38 on the other side, which also provide rotational restriction.
A connector is thus positioned in a subhousing 20 to provide functionally identical
wire engaging slots on both ends, and both sides of panel member 11.
[0015] As may be seen best with reference to Figure 1, both ends of subhousings 20 include
a pair of diametrically opposed axially extending slots 61 and 62 in the cylinder
walls with one of the slots on each end aligned with one of slots 33 or 39 and the
other slots on each end aligned with the recesses formed by trimming blades 34 or
40. Preferably, the subhousing slots and connector members slots coextend for a minimum
of two or three diameters of the wire size to be connected, such that two or three
wires may be connected to connector member 18 on either end thereof, as explained
below. Further inter subhousing slots 63 are provided, coaxially extending with associated
cylinder wall slots 61 or 62.
[0016] As shown best in FIG. 6, slots 61, 62 and 63 have generally the same width, which
is slightly greater then the diameter of the wire to be installed, so as to not engage
the wire during installation. Slots 61, however, are preferably formed to include
relatively thin arcuate axially extending lips 55 and 56 along each opposite edge,
with the width of the opening between the lips 55 and 56 being slightly less than
the diameter of a wire to be installed, such that when a wire is inserted transverse
to its axis it is gripped by the slot 61, thereby providing a mechanical strain relief
for a wire. Although the invention is not limited to specific dimensions, it provides
a slot (61, 62, 63) width of .045", an inter lip opening width of .025", and a lip
radius of .010" for .032" to .035" insulated wire. These relative ratios of dimensions
have been found to permit wires to be relatively easily manually pulled or pressed
in between the lips without undue force during preliminary placement, and to avoid
deformation or weakening of the conductor during installation. Moreover, the arrangement
provides that the wire may slide downward between the lips via the force applied by
the insertion tool, which force is applied on only the portion of the wire lying inside
the subhousing. It shall be noted that slots 61, 62 and 63 are identical for a particular
end of a housing 15 so that all strain relief slots 61 are on a common side of the
subhousings 20.
[0017] Housing 15 includes four flexible biidge members 70-73 and a pair of shoulders 74
and 75 to accommodate snap-in mounting of housing 15 in aperature 12 of panel 11.
Reinforcement wedges 69 may be provided integral with housing 15 to add to the structural
strength of the end subhousings. Each of bridges 70-73 is supported in a spaced apart
relationship with the main body of housing 15 and includes a respective ramping portion
76-79, the cross section of which may be best seen in Figure 3. Four corresponding
tab members 80-83 are provided on the panel member 11 to extend into aperature 12.
Installation of housing 15 in panel 11 is thus accomplished by inserting the unshouldered
end of housing 15 into aperature 12, such that ramps 76-79 engage the respective tabs
80-83 and compress the bridge members 70-73 as the housing 15 is pushed down into
the aperature 12, with tabs 80-83 snapping over the top edge of the bridge members
as shoulder members 74 and 75 engage panel member 11. Housing 15 is thus irremovably
retained in a mounted position on panel member 11.
[0018] The tool provided for and the method for installing wires in a connector member 18
will now be explained with particular reference to FIGS. 3, 4 and 5. In Figure 5,
the wire installing tool according to the present invention is shown in cutaway perspective
view. The tool 90 includes a shaft 91 to be connected to a handle (not shown), for
example a conventional screwdriver handle. The end of shaft 91 includes a tip portion
92 including a cylindrical member 93 having an outside diameter smaller than the inside
diameter of the extent of a subhousing 20 surrounding the connector member 18, and
an inside diameter slightly greater than the outside diameter of a connecting member
18. A center post or punch member 94 is concentrically disposed within cylindrical
member 93, and has a radius slightly smaller than the inside diameter of the connector
member 18. Punch member 94 includes a smaller diameter portion 100 which is spaced
axially apart from the end of punch member 94 so that when the tool is fully inserted
the smaller diameter portion is axially beyond the end of connector member 18. A bored
aperature 101 is provided and extends from the inside of tool 90 to the outside of
both sides of tip 92. The arrangement of smaller diameter portion 100 and aperature
101 facilitates the movement of plastic and metal residue produced by wire trimming
up between members 94 and 95 out of aperature 101, so that the tool does not jam with
residue. Member 93 further includes a shoulder 95 of generally the same outside diameter
of a subhousing 20, such that when the tool is inserted into a subhousing the shoulder
rests on the end edges thereof, and such that the tip 92 of the tool extends downwardly
inside and around a connector member 18.
[0019] Installation of wires and connectors 18 may be accomplished using tool 90 as follows.
As for example shown in Figure 1, a wire to be installed may be layed in slots 61,
62 and 63 (leftmost wire), and manually pulled down across the top of connecting member
18 (rightmost wire) with the excess wire extending outwardly from the slot adjacent
the trimming blade 34 or 40, as determined by which end of housing 15 the wire is
installed in. It will be noticed that for any given side of housing 15 that each connector
member 18 is aligned with its wire receiving slot facing in the same direction such
that wires to be installed are all layed in with the excess wire extending from the
same face of the housing. As explained above, each of lipped slots 61 provide a wire
restriction which is preferably slightly less wide than the out side diameter of the
insulation on a wire to be installed. Thus, a wire may be manually positioned for
insertion by pressing or pulling it into engagement with a slots 61 across the top
of a connector member 18, and retained there until fully installed with tool 90. Once
fully installed, the gripping force of the lipped slots 61 provide an effective strain
relief so that if wires are pulled or bumped after installation the connection with
the connector member 18 is not disturbed.
[0020] With a wire or wires properly positioned in slots 61, 62 and 63 of one or more subhousings,
tool 90 is inserted into the end of a subhousing, as facilitated by the subhousings
reatively large funnel shaped ends 17. As the tool 90 moves into the subhousing, the
funnel shape aids in axially aligning the tool 90 with respect to the connecting member
18, so that the tool 90 engages the wire and pushes it into the wire receiving slot
33 or 34. The trimming blade 34 or 40 of a connector member 18 severs the excess length
of wire and as the wire slides in the slot 33 or 34 such that the insulation of the
wire is pierced by the inside edges of a respective 33 or 34 slot in order to make
an intimate electrical contact and a mechanical connection with the connecting member
18, as illustrated in FIG. 2. The excess length of wire sheared off by cutting edge
34 or 40 may be easily removed manually. As explained above, trimming residue may
travel up the inside of tip 92 of tool 90 and out aperature 101. Also, it shall be
seen that tool 90 pushes the wire further into lipped slot 61 so that the wire extends
substantially transversely from the subhousing when installed.
[0021] Thus, it shall be seen then that the above- described connector module, installation
tool and method of installation provides that a plurality of wires may be secured
in place for installation via the wire gripping slots in a single series of operations,
and then fully installed in a series of installation operations such that switching
back and forth between wire placement and installation with the wire installing tool
is not required where two or more wires are sought to be installed sequentially. Also,
it shall be seen that two or three wires may be installed in a given slot either sequentially
or simultaneously. Moreover, it shall be seen that the installation tool of the present
invention is completely symetrical such that the installation tool does not need to
be oriented other than being axially aligned with a subhousing and connector member.
Significant time savings in wire installation and savings in tool costs are thus accomplished.
Still further, it shall be seen that construction of the housing 15 with a rigid plastic
material in conjunction with the operation of the installation tool results in the
absorbtion by the housing of most of the force applied via the tool, such that deformation
or damage to the connector members 18 is avoided. Last, but not least, it shall be
seen that the connector module of the present invention may be easily mounted on a
panel 11 in a snap in fashion.
1. Electrical connector apparatus comprising:
a plurality of metal split cylinder means each including a slot for receiving and
engaging a insulated wire to form an electrical connection;
a non-conductive housing configured to provide a plurality of cylindrical subhousings
each for concentrically supporting one of said split cylinder means, each of said
subhousings including slots on diametrically opposed sides with one of said subhousing
slots coaxially extending with said split cylinder slot;
said subhousings aligned in two rows with said subhousing slots aligned transversely
to said rows, the subhousings in each row laterally spaced apart to form a plurality
of inter subhousing slots and the subhousings in different rows laterally offset so
that one slot of each subhousing is aligned with one of said inter subhousing slots
whereby wires to be connected may be laid side by side in said subhousing slots before
being inserted in said split cylinders.
2. Electrical connector apparatus comprising:
wire connecting means including an insulating housing, said connecting means for receiving
wires to be connected and engaging the wires in mechanical and electrical conection;
panel means for supporting said housing in an aperature therein;
said housing including on the sidewalls thereof flexible bridge means for snap mounting
and axially displaced shoulder means for slideably snap mounting said housing in said
aperature, said bridge means flexing as the housing is slid into said aperature;
said aperature sized to receive said housing and including tab means for compressing
said bridge means as it is slid into said aperature and for engaging a transverse
edge of said bridge means when it snaps past the panel means, said shoulder means
stopping said housing after said bridge means snaps past the panel means so that when
mounted said shoulder means retains said housing on one side of the panel means and
said edge of said bridge means on the other side.
3. Electrical connector apparatus comprising:
metal split cylinder means including a coaxially extending slot for receiving an insulated
wire and peircing the insulation to form an electrical connection with the conductor,
and including a cutting blade near one end of the cylinder means diagonally opposite
said slot for trimming excess wire length from a wire inserted in said slot;
a generally cylindrical non-conductive housing for concentrically supporting said
split cylinder means therein with the one end of said split cylinder axially displaced
from an end of said split cylinder means, said housing including diametrically opposed
slots with one of said slots coextending with said split cylinder means slot and the
other housing slot aligned with said blade;
wire insertion means including a central post sized to fit inside said split cylinder
means and a cylindrical member coaxially extending around said post and sized to fit
around the outside perimeter of said cylinder means between the cylinder means and
the housing, said tool means further including a shoulder axially displaced from the
one end of said tool to engage the edge of said end of said housing, whereby wires
may be laid across the top of said cylinder means extending through said housing slots
and pressed into said cylinder with said tool means, said tool means causing excess
length to be trimmed on said blade and said wire to be electrically connected in said
slot.