U.S. patent number 3,641,475 [Application Number 04/886,181] was granted by the patent office on 1972-02-08 for intercept connector for making alternative bridging connections having improved contact clip construction.
This patent grant is currently assigned to Bell Telephone Laboratories, Incorporated. Invention is credited to Carleton D. Irish, Harold Painkin.
United States Patent |
3,641,475 |
Irish , et al. |
February 8, 1972 |
INTERCEPT CONNECTOR FOR MAKING ALTERNATIVE BRIDGING CONNECTIONS
HAVING IMPROVED CONTACT CLIP CONSTRUCTION
Abstract
An intercept connector for providing alternative bridging
connections between terminals is disclosed in which circuit paths
and contact clips are combined on a circuit board in predetermined
circuit configurations.
Inventors: |
Irish; Carleton D. (Neptune,
NJ), Painkin; Harold (Matawin Township, Monmouth County,
NJ) |
Assignee: |
Bell Telephone Laboratories,
Incorporated (Murray Hill, NJ)
|
Family
ID: |
25388546 |
Appl.
No.: |
04/886,181 |
Filed: |
December 18, 1969 |
Current U.S.
Class: |
439/80;
439/620.24; 379/332; 439/510 |
Current CPC
Class: |
H01R
31/00 (20130101); H01R 12/721 (20130101) |
Current International
Class: |
H01R
31/00 (20060101); H05k 001/02 () |
Field of
Search: |
;339/17,65,214,219,220,198 |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Champion; Marvin A.
Assistant Examiner: Lewis; Terrell P.
Claims
We claim:
1. An intercept connector for making predetermined multiple
connections between telephone lines fastened to terminals
projecting outwardly from a terminal block, said intercept
connector including a circuit board having a row of parallel
mounting spaces defined by a row of parallel notches cut in one
edge thereof, a contact clip mounted on each of said mounting
spaces and circuit paths disposed on said circuit board and
interconnecting said contact clips in predetermined circuit
configurations, CHARACTERIZED IN THAT each mounting space is
perforated with an aperture and each contact clip is formed from a
single piece of contact metal and includes gripping means for
making end-on engagement with a terminal projecting from said
terminal block, attaching means cooperating with said aperture to
attach said contact clip to said circuit board and aligning means
for locating said intercept connector on said terminal block and
holding it in place after installation, said aligning means
including at least one terminal engaging tab bent up from one side
of said contact clip.
2. An intercept connector in accordance with claim 1 wherein said
attaching means includes a U-shaped hook located at the end of said
contact clip.
3. An intercept connector in accordance with claim 2 wherein said
U-shaped hook includes a locating flap adapted to fit in said
aperture and hold said contact clip in position on said circuit
board.
4. An intercept connector in accordance with claim 1 wherein said
gripping means comprises a spring loop located at one end of said
contact clip.
5. An intercept connector in accordance with claim 4 wherein said
spring loop is bifurcated to form a pair of contact fingers.
6. An intercept connector in accordance with claim 1 wherein said
aligning means includes two terminal engaging tabs bent up from
opposite sides of said contact clip.
7. An intercept connector in accordance with claim 1 wherein said
notches are associated in pairs of progressively deeper cuts in
said circuit board.
Description
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention pertains to connectors and relates particularly to
those which make bridging connections between circuits which appear
on neighboring terminals of a terminal block.
2. Description of the Prior Art
Bridging connectors of the type considered here are used to
intercept and transfer calls made to unassigned telephone numbers.
Typically, interception and transfer is made by a bridging
connection at the main frame, i.e., the place where wires from the
telephone numbers leave the central office. At any given time, a
great many telephone numbers are not assigned and will require
intercept and transfer. As a result, there is a continuous and
usually extensive demand for bridging connections. If this demand
is to be satisfied at reasonable cost, connectors must be
inexpensive to make, central office personnel must be able to make
bridging connections quickly and efficiently, and the resulting
connection must be reliable.
Accordingly, one object of this invention is to achieve speed, low
cost and reliability in handling bridging connections.
Bridging connectors are well known and are available in variety of
forms. One, for example, commonly called an intercept connector,
comprises a number of contact clips which are mounted on a printed
circuit board and interconnected by circuit paths. Intercept
connectors of the type described are used extensively in telephone
systems and, in gross, represent a relatively large investment.
Since efficient business operation requires a continuous search for
cost reductions, reliable intercept connectors which are
inexpensive to make and easy to use will satisfy an urgent
demand.
Accordingly, another object of this invention is to provide an
intercept connector which is inexpensive to make and which is
simple and reliable to use.
SUMMARY OF THE INVENTION
According to a preferred embodiment of this invention, an intercept
connector includes a circuit board having a row of parallel
mounting spaces defined by a row of notches cut in one edge
thereof, an aperture cut in each mounting space, circuit paths
linking mounting spaces in predetermined patterns and, in each
mounting space, a contact clip equipped with a locking hook, a
spring loop and at least one tab, the locking hook being located at
one end of the contact clip and encircling a portion of an
associated mounting space, projecting through the aperture therein
and electrically engaging the end of a circuit path, the spring
loop being located at the other end of the contact clip and the tab
being located between the locking hook and the spring loop.
According to one feature of this invention, each contact clip is
blanked from a single piece of contact material stock.
According to another feature of this invention, the spring loop on
each contact clip is bifurcated at one end to engage a terminal at
two points, thereby increasing the likelihood of good mechanical
and electrical connection.
According to another feature of this invention, each tab on the
contact clips facilitates engagement between its associated spring
loop and a terminal by guiding the terminal into the spring loop as
the intercept connector is installed and contributes to contact
reliability by restraining side-to-side movement of the circuit
board after the intercept connector is installed, thereby reducing
the possibility of inadvertent disconnect or cross connection
between terminals.
According to another feature of this invention, the locking hook on
each contact clip is U-shaped and includes a flap to facilitate
attachment to a mounting space on the circuit board.
According to another feature of this invention, attachment of the
contact clip to the circuit board is simplified by associating the
notches in the circuit board in pairs having progressively deeper
depths.
A better understanding of these and other features of this
invention will be aided by the following detailed description when
taken in conjunction with the drawing.
BRIEF DESCRIPTION OF THE DRAWING
FIG. 1 is a top plan view of an intercept connector made in
accordance with this invention;
FIG. 2 is a bottom plan view of the intercept connector illustrated
in FIG. 1;
FIG. 3 is a top plan view of an intercept connector illustrating an
alternative form of the intercept connector shown in FIG. 1;
FIG. 4 is an end elevation view taken in section along the line
4--4 in FIG. 3;
FIG. 5 is an end elevation view taken in section along the line
5--5 in FIG. 1;
FIG. 6 is a top plan view of a contact clip in the form it appears
when first blanked from flat stock;
FIG. 7 is an elevation view with portions broken away and
illustrating an intercept connector mounted on a terminal block;
and
FIG. 8 is an end elevation view of the intercept connector and
terminal block illustrated in FIG. 7.
DETAILED DESCRIPTION
An intercept connector 10, as illustrated in FIG. 1, comprises
contact clips 11, a circuit board 12, a diode mounting area 13,
diode mounting holes 14 and circuit paths 15.
The circuit board 12 is a modified rectangularly shaped insulating
board made from material such as fiberglass epoxy. As shown in FIG.
1, the corners are sheared away on one edge for ease in handling
while six notches 16 are cut in the other edge. As illustrated in
FIG. 1, the corners are sheared asymmetrically. With an
asymmetrical shape, particular bridge connections can be visually
identified when the intercept connector is installed. As best seen
in FIG. 3, the notches 16 are arranged in series and each pair is
cut a little deeper than its neighbor. As shown in FIGS. 2 and 3,
conductor ribbons 17, which begin at the edge of each notch 16, are
located in pairs on either side of the circuit board 12. As shown
in FIG. 2, each pair of ribbons 17 is perforated with an aperture
18. Finally, the ribbons 17 are selectively interconnected to each
other by the circuit paths 15. The circuit paths 15 and ribbons 17
are conductors of electricity and are conveniently formed by
conventional printed circuit techniques.
As seen in FIGS. 1 and 5, a contact clip 11 is located in each
notch 16 and soldered to a pair of ribbons 17. As shown in FIG. 5,
each contact clip 11 is a unitary element having a spring loop 20
at one end, a locking hook 21 at the other end and a pair of tabs
22 in the middle.
As best seen in FIG. 1, each spring loop 20 is turned up and
bifurcated at its free end to form two contact fingers. In use, the
bifurcated ends of a spring loop 20 grip a terminal to make a
mechanical and electrical connection. The turned-up ends preserve
the terminal surfaces, while bifurcation permits the spring loop 20
to engage the terminal at two independent positions, thereby
tending to improve electrical contact or compensate for misaligned
or irregular terminals.
The locking hooks 21, as best seen in FIG. 5, attach the contact
clips 11 to the circuit board 12. Each is U-shaped, fits in a notch
16 and engages the associated ribbons 17 to form a mechanical and
electrical connection. Also, each includes a locking flap 23 which
extends into an aperture 18 and, when bent over, locks the contact
clip 11 to the circuit board 12. Furthermore, the locking flap 23
inhibits movement of the contact clip 11 when it is installed on or
removed from a terminal.
The tabs 22, as best seen in FIG. 5, are located between the spring
loop 20 and the locking hook 21 on either side of the contact clip
11. When the intercept connector 10 is inserted over a line of
terminals, the tabs 22 guide the terminals into the spring loops 20
and hold them in place when the intercept connector 10 is seated.
Consequently, the intercept connector 10 is restrained against
sliding movement and thereby prevented from causing false
connections or breaking existing connections. While two tabs 22 are
shown on each contact clip 11, one can be made to serve equally as
well.
Each contact clip 11, as can be seen from FIG. 6, is designed for
fabrication from a single piece of flat stock. The stock material
must be electrically conducting and phosphor bronze has proved to
be acceptable. As can be seen from FIGS. 5 and 6, the contact form
is first blanked from the flat stock and then bent into the
illustrated configuration.
The intercept connector 10, when installed on a terminal block
having rows of terminals, usually engages all of the terminals in a
row. In the embodiment illustrated in FIG. 7, for example, parallel
rows of terminals 30 are disposed on opposite sides of a terminal
block 31. When the intercept connector 10 is installed, as shown in
FIG. 7, the tabs 22 speed installation by guiding the terminals 30
up under the lips of the spring loops 20. Thereafter, as can be
seen from FIGS. 7 and 8, the tabs 22 contribute to circuit
reliability by limiting side-to-side sliding of the intercept
connector 10, thereby preventing accidental disengagement or cross
connection.
Alternative bridging connections are readily obtained with the
disclosed intercept connector 10. As can be seen by comparing FIGS.
1 and 3, a circuit segment 26 and a recess 27 occupy superimposed
positions on the surface area 13. Generally, the surface area 13 is
bounded on either side by the top of the ribbons 17 and the edge of
the circuit board 12, respectively, and is bounded on either end by
a hypothetical line projecting along the inner edges of the two
notches 16 which are second in from each end, respectively.
Both the circuit segment 26 and the recess 27 are located between
the diode mounting holes 14. The circuit segment 26, however,
extends from the edge of one hole 14 to the edge of the other.
Consequently, terminals 30, which are bridged by the configuration
shown in FIG. 1, will be linked by a short circuit.
In order to change the character of the connection from a short
circuit to a diode bridge, for example, only two simple steps are
required. First, the recess 27 is cut in the circuit board 12
through the circuit segment 26. Conversion is then completed by
mechanically and electrically installing a diode in the mounting
holes 14 and recess 27.
As illustrated in FIG. 4, the recess 27 may conveniently be a cup
having a preferred depth greater than half the thickness of the
circuit board 12. Alternatively, however, it can be an aperture or
window cut through the circuit board 12. In either case it performs
a dual function, i.e., it removes a portion of the circuit segment
26 when it is cut, thereby opening up the short circuit, and it
provides a protected pocket in which the diode may be mechanically
mounted.
In conclusion, an intercept connector has been disclosed which is
capable of quick installation, ease of use and reliable service.
Furthermore, it is inexpensive to make and is readily converted
from one form of bridge connection to another. While only one
embodiment of the invention has been illustrated, it will be
understood that the disclosed embodiment is only illustrative of
the principles of the invention and many other embodiments will
occur to those skilled in the art which falls within the scope of
the invention.
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