U.S. patent number 3,611,264 [Application Number 04/787,453] was granted by the patent office on 1971-10-05 for wire connecting blocks.
This patent grant is currently assigned to Bell Telephone Laboratories, Incorporated. Invention is credited to Benjamin C. Ellis, Jr..
United States Patent |
3,611,264 |
Ellis, Jr. |
October 5, 1971 |
WIRE CONNECTING BLOCKS
Abstract
This disclosure describes an indexing strip and connecting block
scheme for equipment and station interconnections for key telephone
systems. The indexing strip is a plastic molding with two narrowly
spaced rows of teeth. The insulated line wires are placed across
the slots between the teeth. The connecting block straddles the
teeth and its pin connectors are each guided into piercing contact
with a respective wire. The blocks and strips lock, once engaged.
Wall mountings for the strips include bases with V-shaped insertion
tracks.
Inventors: |
Ellis, Jr.; Benjamin C.
(Baltimore, MD) |
Assignee: |
Bell Telephone Laboratories,
Incorporated (Murray Hill, NJ)
|
Family
ID: |
25141522 |
Appl.
No.: |
04/787,453 |
Filed: |
December 27, 1968 |
Current U.S.
Class: |
439/403;
439/404 |
Current CPC
Class: |
H04Q
1/141 (20130101); H01R 4/2429 (20130101); H01R
43/015 (20130101) |
Current International
Class: |
H01R
4/24 (20060101); H04Q 1/14 (20060101); H01R
43/01 (20060101); H04Q 1/02 (20060101); H01r
009/08 () |
Field of
Search: |
;339/65,66,91,97-99,217 |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: McGlynn; Joseph H.
Claims
I claim:
1. Apparatus for interconnecting a plurality of groups of wire
comprising in combination:
an insulative indexing strip comprising a body portion with a flat
top floor,
two parallel rows of corresponding teeth, the teeth in each row
spaced apart to form fanning slots,
the corresponding teeth pairs being held in close proximity by
separators, each separator arising from a level below said top
floor and connecting to the corresponding said teeth pair between
said top floor and a point below the ends of said teeth,
adjacent ones of said separators and their respective teeth forming
a well; and
a connector block comprising a body member with a flat top floor,
two rows of corresponding teeth extending vertically from said
floor, the teeth in each row being spaced by amounts equal to the
spacing between the teeth in said index strip;
corresponding ones of the teeth in said connector block rows being
joined in a narrow spacing by a separator;
said block body further comprising grooves formed by the sides of
said teeth in a first one of said teeth rows, each said groove
culminating in a base below said floor level;
said block further comprising a top row of oblong locking slots
disposed directly beneath the fanning slots formed by said teeth
row opposite to said first teeth row;
a connector pin comprising first and second beveled and tapered
insulation-piercing ends, and first and second oppositely directed
arms extending from opposite faces of said pin;
the arms of each said pin engaging respectively the said groove
base and said oblong slot above said base thereby to lockably
engage in said connector;
the top end of each said pin being disposed below the tops of said
connector block teeth, and the bottom end of each pin protruding
beyond said connector block body; and
said body further comprising first and second legs spaced apart,
each said leg including an inwardly directed vertical guide member,
said guide members engaging the index strip fanning slots when said
block is placed upon said strip.
2. Apparatus in accordance with claim 1, further comprising a
bottom row of cylindrical slots through each said leg of said
connector block, said bottom slots being spaced to align with the
centers of said index strip teeth when said block is on said strip;
and said index strip teeth each further including an outwardly
extending nub for engagement with said connector block bottom
slots, engagement occuring when the bottom ends of said connector
block legs are spaced slightly above the top floor of said index
strip.
3. Apparatus in accordance with claim 2, wherein the teeth of said
index strip are offset to one side of said top floor thereby
providing a wide platen along one side of said floor to aid in
severing wires.
4. Wire interconnection apparatus comprising:
an insulative indexing strip comprising: a base block comprising a
floor, two narrowly separated parallel rows of spaced corresponding
teeth rising from said floor, the spaces between corresponding
teeth pairs defining fanning slots, a separator linking each
corresponding pair of teeth of said rows and extending below said
floor to define walls between adjacent said separators;
an insulative connector block comprising a body, two narrowly
separated rows of spaced corresponding teeth stemming from the top
of said body, a separator element linking each corresponding pair
of said teeth, first and second spaced legs extending from the
bottom of said body opposite said teeth, each said leg comprising
plural spaced inwardly directed guide members each for engagement
with a respective one of said index strip fanning slots; and
a metallic connector grippingly disposed between each adjacent
connecter block separator element and having first and second
insulation-piercing ends, each said first end extending beyond said
body top and each said second end extending beyond said legs for
insertion into said wells of said indexing strip.
Description
This invention relates to interconnections between a multiplicity
of wires; and particularly to connections between the telephone
lines, and the stations and equipment of a key telephone
system.
BACKGROUND OF THE INVENTION
In the application of B. C. Ellis, Jr. et al. filed Apr. 28, 1967,
Ser. No. 634,567 and assigned to applicant's assignee, there is
described a versatile inexpensive and simple wire-connecting or
indexing strip and connecting block configuration particularly
useful in key telephone system wiring arrangements. In that scheme,
wires of specific telephone lines are disposed across an indexing
strip and station connections to them are made by connector blocks
that include insulation-piercing pin connectors.
The present invention, while similar in general principle, improves
in several important respects upon the specific design and
configuration of the indexing strips and associated connector
blocks.
For example, the combs of the earlier indexing strip were widely
spaced and the wires supported therein thus spanned a relatively
wide groove. This allowed wire slack to occur or develop with a
significantly increased risk or wire misalignment with the pin
connectors of the block. The wide groove design further required
more labor for wire installation. The connectors of the block also
were staggered, making for a relatively wide connector block.
Additionally, the earlier design was found to require more space
than strictly necessary for support of, and electrical connection
to, the telephone line wires.
A further problem with the foregoing and other connector-block and
strip arrangements is the manner of interlocking the block and the
strip. It is desirable to ensure that the block, once applied to
the strip, stays in place. In earlier arrangements, this feature
was difficult to achieve with simplicity.
Accordingly, the principal object of the invention is to further
improve the mechanisms by which changes and rearrangements are made
in a telephone key system wiring pattern.
A further object of the invention is to reduce the space needed for
such an arrangement.
A further object of the invention is to avoid disrupting service
when undertaking rearrangements in key system wiring.
A further object of the invention is to achieve a key telephone
system modular wiring scheme that provides space for wires and
cables, and also permits rapid and orderly installation and growth
of terminal arrays.
A still further object of the invention is to expeditiously store
and readily identify groups of wires representing key telephone
system circuit functions until interconnection is required.
SUMMARY OF THE INVENTION
These objects are broadly realized in an indexing strip and
connector block configuration in which the intermediate structure
between the index strip teeth is substantially eliminated, bringing
the teeth directly adjacent each other. In one embodiment, each
pair of corresponding teeth are held in separation by a strength
element that extends beyond the base of the strip.
In accordance with one feature of the invention, the pin connectors
of the connecting block are arranged in a single line; and
importantly, will accommodate to any part of the index strip and
not merely discrete sections thereof.
Once installed, each block is locked pursuant to another aspect of
the invention by the engagement of each separate tooth to the block
through a nub projection and indentation arrangement. When so
engaged, the block can only be removed with mechanical aid.
Each index strip further is advantageously of a unitary one-piece
mold; and includes an inverted V-groove in the base bottom to
facilitate mounting strips in an underlying mounting plate equipped
with like grooves.
Compact multiple appearances of a given telephone line or lines is
achieved pursuant to the invention by arraying a number of such
strips so that the line wires are successively disposed between the
corresponding teeth of each strip. Each connector block is placed
on a different indexing strip but connected to the same telephone
line; and thus its connection is independent of the other
blocks.
DESCRIPTION OF THE DRAWING
FIG. 1 is a perspective side view of a portion of an indexing
strip, and a full connector block;
FIGS. 2, 2A, 2B, 2C, and 2D are side, end sectional, end, bottom,
and top views respectively of the indexing strip;
FIGS. 3, 3A, 3B, and 3C are front, top, side and side sectional
views of the connector block;
FIGS. 4, 4A, and 4B are top, side, and front views respectively of
a mounting scheme for the index strips;
FIG. 5 is a side perspective sketch of the pin connector used in
the blocks;
FIG. 6 is a perspective diagram of an index strip and its mounting
base;
FIG. 7 is a perspective diagram of indexing strips mounted in a
base and wired for multiple line appearances; and
FIGS. 8, 8A and 8B are perspective, frontal and side views
respectively of a seating tool.
DETAILED DESCRIPTION OF AN ILLUSTRATIVE EMBODIMENT
As seen in FIG. 1, the invention advantageously is embodied in an
index strip 100 and an associated connector block 201. Strip 100
consists of a base block 101 with sidewalls 102, 103, each wall
comprising an in-line row of identical teeth 104. Between all
adjacent teeth in both rows are spaces of like size, which function
as fanning slots 105. Corresponding pairs of teeth 104 of the two
sidewalls are connected by separators 106, from a point below the
teeth 104 ends. Each adjacent two separators together with the four
associated teeth 104, form a well 107 whose bottom is below the
index strip floor 108, as seen in FIG. 2A. The wells 107 are
centered under the fanning slots 105.
Each tooth 104 includes an outer nub 109 seen in FIGS. 2, 2A and
2B, for example. Nubs 109 are positioned below the tops of
separators 106; and, as will be described, serve to lock connector
blocks 201 to the index strip. The index strips 100 include slanted
legs 110 and 111 which as seen in FIG. 6 engage a like-shaped
V-groove 112 in a mounting plate 113. A slot 114 between the legs
provides a means for adjusting the frictional gripping properties
of legs 110 and 111.
As seen in FIGS. 2A and 3C, for example, the index strip teeth 104,
pursuant to one facet of the invention, are placed to one side of
the base block floor 108 thus affording a relatively wide side
designated 108a of floor 108. The purpose of wide side 108a is to
afford a platen sufficiently wide to trim off the wires in one
stroke with a hand-cutting tool having a circular rolling cutter. A
result of such a cut is shown, for example, in FIG. 7. The legs
110, 111 run the entire length of the index strip, as seen in FIG.
2C. Similarly, as shown in FIG. 2D, the teeth 104 are disposed as
described along the entire length of the index strip.
The connector block 201 consists of a body 202 and a pair of
sidewalls 203, 204 extending from the body top. Each sidewall
consists of a row of teeth 205 of like size, shape and spacing as
teeth 104 of index strip 100. The teeth 205 are spaced as shown in
FIGS. 3 and 3A, the spaces therebetween defining fanning slots 206.
Each pair of corresponding teeth 104 is joined by a separator 207.
Adjacent separators 207, together with associated teeth 205 define
an upper cavity 208 which houses one end of a pin connector 212
such as shown in FIG. 5.
Pin connector 212 includes beveled tapered ends 220, 221 which are
formed by a coining trim tool into sharp insulation-piercing edges,
and corresponding slots 222, 223 which receive and grip a wire. Pin
connector 212 is formed with mounting arms 224, 225 extending from
opposite faces. Pin connectors 212 are capable of making a
permanent, low resistance, gastight connection to insulated
conductors without prior stripping of the insulation. Also, because
of their resilient nature, they may be used repeatedly.
As seen in FIG. 3C, connector block 201 includes a row of oblong
locking slots 213 which are centered directly beneath each fanning
slot 206. Slot 214 which is opposite to locking slot 213 is for the
purpose of inserting an extracting tool if it should be necessary
to probe to aid in engaging appendage 224 into locking slot
213.
As seen in FIGS. 3 and 3B, each connector block leg includes
inwardly directed vertical guide members 218, which are in
alignment with the fanning slots 206. The guide members 218 engage
the index strip fanning slots 105 when the block is placed upon the
strip.
Pursuant to one facet of the invention, the teeth on one side of
connector block 201 such as teeth 205a of FIG. 3C form with their
adjacent downwardly extending sides a series of pin grooves 215
that terminate at groove base 216. The pin connector 212 is
installed by placing same into upper cavity 208 until the arm 224
clears slot 213 and locks thereinto. At this point the arm 225 on
the other side of pin connector 212 is approximately in contact
with the groove base 216. A slight clearance of, for example, 5
mils is provided between the vertical distance between the flat
portions of arms 224, 225 and the distance designated 217 between
the top of slot 213 and the groove base 216.
When in place, the point of pin connector 212 is substantially
level with the top of separator 207, as seen in FIG. 3C. The bottom
end 221 of pin 212 extends beyond the base of legs 209 as seen in
FIG. 3B, by an amount sufficient to engage a wire 226 placed in the
fanning slots 103 of index strip 100, as shown in FIG. 3C.
A row of cylindrical slots 211 shown in FIGS. 3 and 3B placed
through the legs 209 serve to capture the nubs 109 molded into the
teeth 104. Nubs 109 and slots 211 are arranged to mate at a point
where the base of legs 209 affect a clearance with the floor 107 of
the indexing strip 100 as shown in FIG. 7, for example.
FIGS. 4, 4A, and 4B depict a preferred means for mounting the index
strips 100. A pair of brackets 301 mountable on a vertical
backboard, not shown, comprise legs 310 joined by a flange 311 that
includes a top fanning strip 302. The latter consists of several
fanning slots 306 and periodic wire guide slots 303, which extend
well down into flange 311. An index strip mounting plate 113 is
supported by fasteners such as 305 between the flanges 311 and at a
level that clears the bottom of each guide slot 303 as seen in FIG.
4A. Mounting plate 113 is formed with guide slots 304 as seen in
FIG. 4 which correspond in position to the guide slots 303 in the
fanning strip 302.
Mounting plate 113 is provided with spaced parallel V-grooves 112
as seen in FIG. 6 which accommodate the slanted legs of each index
strip as already described. The grooves 112 are spaced so as to
correspond with respective ones of the fanning slot 306 as seen in
FIG. 4A. The index strips are held in place in the V-grooves 112 by
virtue of the resiliency afforded the legs 110, 111 by the notch
114.
Wires are installed in the fanning slots 105 of strip 100 as well
as in the fanning slots 206 of connector block 201, advantageously
by means of the seating tool 401 shown in FIG. 8. This tool
consists of a handle 402 and a seating head 403. The head 403
consists of a pair of side ribs 404 which as shown in FIG. 8B
engage the top portions 202a of body 202. A series of internal rib
pairs 405 are disposed in spaced array between the ribs 404. The
spacing corresponds to the space between fanning slots 105, as seen
in FIG. 2. The ends of ribs 405 and of 404 are coplanar as seen in
FIG. 8.
Wires are snubbed into the fanning slots 105 and thereafter seated
by applying the head across the teeth 104 which guide the ribs 405
downwardly unto the wires, firmly seating them across the bottoms
of the fanning slots 105. As a tool for seating wires into the ends
220 of connector block pin 212, the center rib 406 of head 403
comes into play as shown in FIG. 8B.
OPERATION
As seen in FIG. 4, a group of wires associated with specific
telephone lines are selected out from a cable (not shown) and led
through the slots 303, 304. Thereafter, the wires 309 are dressed
across a group of, for example, 5 index strips 100 in the manner
illustrated in FIG. 7. The wire connecting strip 100 provides a
means of storing wires in a prearranged sequence for identification
purposes. When circuit connections are required the connecting
block equipped with the proper number of connectors is inserted
into the connecting strip. Connections to all wires required for
the circuit connection are made simultaneously. Cross-connecting
wires are then inserted in the top of the connecting block.
The connecting blocks may be inserted anywhere along the connecting
strips and may be provided in sizes of, for example, up to 10 pin
connectors 212 per connecting block. By having this flexibility
available, any changes in application or number of wires per
circuit group may be accommodated.
The interlock of strips 100 and connector blocks 201 provides
mechanical rigidity necessary to withstand field handling, and
inadvertent removal of connecting blocks during wire work in the
terminal arrangement.
Connecting blocks are installed only as customer service is
required. Investment thus is only made in connectors which return
revenue. When service is discontinued, it is not necessary to
remove the connecting block but only the expendable
cross-connecting wires terminated on the top of the connecting
block.
The invention has been described principally in connection with
insulated conductor, but it should be clear that it applies equally
to connections between bare wires. The multiple appearance wires of
FIG. 7, for example, might in given applications be uninsulated
conductor. The inventive structure described does not change for
those applications.
The invention is embraced in spirit within the claims to follow
which define its scope.
* * * * *