US 3641475 A
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.
Description (OCR text may contain errors)
United States Ffifififi'fifi [is] 3,641,475 Irish et a1. Feb. 8, 1972  INTERCEPT CONNECTQR FQER  References Cited ifiiififiiwfifififi i vfi CONTACT CLIP CONSTRUCTHON 2,849,700 8/1958 Perkin ..339/15 B X 3,138,417 6/1964 Garrett.. 339/150 B X 721 lnventors: Carleton 0. Irish, Neptune; Harold Pain- 2,269,241 1/1942 Ayefs -339/219 X kin Malawi Township Monmouth 2,962,692 11/1960 White ..339/220 coamy both ofN J 2,968,780 1/1961 Roswell ..339/17 R 2,993,188 7/1961 Anderson ..339/17 LC  Assignee: Bell Telephone Laboratories, Incorporated, ,538 3/1962 Deakin 339/17 LC X Murray Hill, NJ. 3,235,829 2/1966 Haefele ..339/17 LC 3,312,927 4/1967 Garrett ..339/17 LC  Filed: Dec. 18, 1969 Primary Examiner-Marvin A. Champion ] Appl' 886,181 Assistant ExaminerTerrell P. Lewis AttorneyR. J. Guenther and Edwin H. Cave  U.S.CI. ..339/17 L, 339/17 R, 339/151 B 511 Int. C1. -1051: 1/02 [571 ABSTRACT of Search 7, 65, 214, intercept connector for providing alternative con- 339/198 nections between terminals is disclosed in which circuit paths and contact clips are combined on a circuit board in predetermined circuit configurations.
7 Claims, 8 Drawing Fig ures g) E l5 I4 26 Q l l l 4 l 3 INTERCEPT CONNECTOR FOR MAKING ALTERNATIVE BRIDGING CONNECTIONS HAVING IMPROVED CONTACT CLIP CONSTRUCTION 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.
According y, 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 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 tenninal 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 U-shaped 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 alongthe line 55 in FIG. 1;
FIG. 6 is a top plan view of a contact clip in the form it appears when first blanked from fiat 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.
DETAHJED osscnn'mou 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 comers are sheared away on one 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 arrangedin 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 l5 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 1 l 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 stack. The stock material must be electrically conducting and phosphor bronze has proved to be acceptable. As can be seen from FIGS. 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 tenninals, 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 is installed, asshown 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 sideto-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 l7 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 andthe recess 27 are located between the diode mounting holes 14. The circuit segment 26, however, extends from the edge of one hole 14 to he edge of the other. Consequently, terminals 30, which are bridged by the configuration shown in FIG. I, 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 andmany other embodiments will occur to those skilled in the art which falls within the scope of the invention.
1. An intercept connector for making predetennined 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 dpaths disposed on said circuit board and interconnecting sai circuit configurations, CHARACTERIZED IN THAT each mounting space is perforated withan 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 I 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.
contact clips in predetermined