Buss Connector

Abstract

An electrical buss connector for bussing together a series of plate mounted wire-wrap pins. The connector comprises a flat strip of metal which is provided with elongated slots at intervals along its length. Cut-outs are formed in opposed edges of each slot between its ends for locating and gripping prescribed pins when the strip is pressed down on the pins. The sharp edges of the cut-outs wipe and clean the pins as the strip is forced downwardly on them so as to assure an excellent electrical connection, while the strip assumes a low profile configuration with the mounting plate.

Description

BACKGROUND OF THE INVENTION

This invention is in the field of electrical hardware. It deals particularly with electrical hardware especially suited for high density computer circuitry or the like.

It is now common practice in computer circuitry, for example, to employ terminal plates seating thousands of electrical terminals. These plate-type terminals are conventionally of the wire-wrap type, adapted to have wire leads wrapped onto the wire-wrap pins of their contacts by well-known techniques.

It is frequently a requirement in large plate connectors that various of these wire-wrap pins are interconnected; i.e., bussed together. Bussing is conventionally accomplished by interconnecting a plurality of the wire-wrap pins with individual wire leads and wire-wrap connections, for example, or wire leads and solder connections. An alternative to such wire interconnection is to provide a fabricated connector. An example of such a connector is illustrated in the Sullivan et al U.S. Pat. No. 3,488,620. This patent discloses a U-shaped buss strip for interconnecting the wire-wrap pins of a series of terminal connectors wherein the strip is retained on the pin by the spring-like action of its downwardly extending legs.

There are marked disadvantages to each of the known bussing arrangements, exemplified by those referred to, however. The use of individual wire leads with wire-wrap or solder connections, for example, requires considerable labor and, accordingly, expense to buss together a selected series of wire-wrap pins. The buss connector strip shown in the Sullivan et al; patent was an improvement, but this construction is severely limited in versatility. For example, the Sullivan et al. clip is not easily adaptable to bussing alternate pins together, or irregular sequences of pins. Furthermore, relatively poor electrical connections are frequently established between the buss strip and various terminal pins because of slight irregularities in pin alignment, as well as for other reasons.

SUMMARY OF THE INVENTION

A primary object of the invention is to provide a new and improved electrical buss connector for bussing a series of plate terminal wire-wrap pins together. It is another object to provide a simple, economical, yet highly efficient buss connector for joining any selected sequence of wire-wrap pins. It is still another object to provide a buss connector which effectively wipes and cleans the connecting surfaces of the wire-wrap pins when it is pressed into operational relationship. A further object is to provide a buss connector which permits a simple connection to and disconnection from the terminal pins. Yet a further object is to provide a buss connection which has an extremely low profile, and, accordingly, facilitates high density connections being made to the wire-wrap pins without interference by the buss connector.

The foregoing and other objects are realized in accord with the present invention by providing a flat buss strip fabricated of an excellent conducting material, such as phosphor-bronze or the like. The strip is elongated and, at intervals along its length, is provided with longitudinally extending die cuts or slots. One end of each slot is preferably cut open to an edge of the strip so that at least one elongated side section of the strip will spring resiliently outward in the plane of the strip when the strip is pressed downwardly over a pin.

Pin locating cut-outs are provided in opposed surfaces of the slots. The strip is pressed downwardly over a terminal pin with the pin positioned in the locating cut-outs, and the sharp edges of the cut-outs wipe the sides of the pin to clean it and establish an excellent electrical connection while the strip moves into a low profile relationship with the plate itself.

In one aspect of the invention, the closed ends of one or more slots are enlarged to provide clearance apertures for selected adjacent terminal pins. Thus, a selected series of terminal pins remains unconnected from the buss strip. It is also contemplated that spreader probe locating cut-outs may be provided in the slots between clearance apertures and pin locating cut-outs whereby the slots can easily be widened to facilitate removal of the strip by insertion of a suitably formed spreader probe.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention, both as to its organization and method of operation, taken with other objects and advantages thereof, is best understood by reference to the following specification read in conjunction with the attached drawings, in which:

FIG. 1 is a perspective view of a portion of a terminal plate mounting terminals with wire-wrap pins bussed together by a buss connector embodying features of the present invention;

FIG. 2 is a side elevational view of the plate, terminal and buss connector arrangement of FIG. 1 (illustrating additional terminals);

FIG. 3 is a top plan view of the buss connector of FIGS. 1 and 2;

FIG. 4 is a view similar to FIG. 2 showing two buss connectors joining different pairs of terminals;

FIG. 5 is a top plan view of a buss connector embodying features of a second form of the invention;

FIG. 6 is a top plan view of a buss connector embodying features of a third form of the invention; and

FIG. 7 is a top plan view of a buss connector embodying features of a fourth form of the invention.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

Referring now to the drawings, and particularly to FIGS. 1 and 2, an electrical connector assembly is seen generally at 10. The connector assembly 10 comprises a terminal plate 11, usually fabricated of an aluminum alloy, mounting a plurality of terminals 12 in suitably formed apertures. The terminals 12 are of generally well-known construction, comprising contacts extending through insulating bushings 16 which are, in turn, mounted in the plate 11.

Extending upwardly from the plate 11 on one side of it are the wire-wrap pins 25 of the contacts. The wire-wrap pins 25 are adapted to be interconnected with various other components in computer circuitry, for example, by wire leads and conventional wire-wrap connections (not shown). According to the present invention, a prescribed series of these pins 25 are also bussed together by a buss connector 30 embodying features of the invention.

Referring now also to FIG. 3, the buss connector 30 comprises an elongated flat strip 31 of a highly conductive alloy such as phosphor-bronze, for example. The flat strip 31 is elongated in the path of a row of the pins 25 and receives pairs of these pins in corresponding patterned slots 35. In the form of the buss connector 30 illustrated in FIGS. 1-3, each of these patterned slots 35 receives the pin 25a which makes an electrical connection with the strip 31 while the pin 25b passes through the strip without making an electrical connection.

The patterned slot 35 is preferably formed by die cutting, although other cutting techniques might be employed and includes a longitudinally extending elongated slot section 36 connected at one end by a perpendicular slot section 37, with one of these side edges 40 of the strip 31.

Nearest the end of the slot section 36 adjacent the perpendicular slot section 37, a pair of pin locating and gripping cut-outs 45 are formed in the opposed edge surfaces of the slot section 36. The length of each of these cut-outs 45, i.e., the longitudinal dimension relative to the slot section 36, is greater than the corresponding dimension of the wire-wrap pin 25a. In the present illustration, the wire-wrap pins 25a are 0.025 inch square pins.

The width of these cut-outs 45, i.e., their dimensions transversely of the slot section 36, are normally less than the corresponding dimension of the wire-wrap pins 25a. The import of these dimensional relationships will hereinafter be discussed in detail in relation to the function and operation of the buss strip 31.

At the opposite end of the slot section 36, displaced a substantial distance in the strip 31 from the pin locating and gripping cut-outs 45, are substantially larger rectangular cut-outs which define a clearance hole 47 through the strip 31. The clearance hole 47 is square and has overall dimensions substantially greater than the corresponding cross-sectional dimensions of the pin 25b. The clearance hole 47 is spaced from the pin locating cut-outs 45 at a distance corresponding to the spacing of the pins 25a and 25b, so that the pin 25b may extend through the clearance hole 47 without making contact with the strip 31. To permit the dimensions of the clearance hole 47 to be of the substantially large nature required for this end, the strip 31 is widened on both sides of the hole, as at 49, to provide sufficient strip material for maintaining the strip integrity while permitting die cutting of the substantially large hole 47.

Intermediate the clearance hole 47 and the pin locating cut-outs 45, the opposed edge surfaces of the slot section 36 are formed outwardly generally in semi-circles to define a round hole 52 for a spreader probe (not shown). The use of a spreader probe in conjunction with the spreader probe hole 52 in the slot section 36 will hereinafter be discussed in detail in relation to the function and operation of the buss strip 31.

In practice and operation, the buss strip 31 is cut elongate in the pattern of the pins 25a which it is designed to interconnect. The terminal pins 25a and 25b are arranged in a straight line row. Slot complexes 35 are formed in the strip 31 at intervals along the length of the strip corresponding to the spacing between pairs of pins 25a and 25b.

The strip is then pressed downwardly onto the row of pins 25a and 25b, with the locating cut-outs 45a over the tips of pins 25a and the clearance holes 47 over the tip of pins 25b. The conventional pyramidal tips of these pins enter corresponding cut-outs 45 and clearance holes 47, respectively, as the strip 31 moves over them. Because the transverse dimensions of the cut-outs 45 are collectively less than the corresponding dimension of the pin 25a, the slot section 36 is spread as the buss strip side section 60 is forced away from the opposite side section 61 of the strip. The side section 60 resiliently bows outwardly in the plane of the strip 31 as it is spread away from the side section 61 by the entering pin 25a, thus widening the slot section 36. The cut-outs 45 are purposely formed so that they wipe corresponding sides of the pins 25a as they pass through the cut-outs, cleaning the pins and forming excellent electrical connections between the pins and the strip 31.

The pins 25b pass through the clearance holes 47 without touching their sides, due to the enlarged size of the clearance holes. The strip 31 is forced downwardly until it rests on the mounting bushings 16 for the contacts, in which position it defines an extremely low profile with the terminal plate 11.

The strip 31 grips the terminal pins 25a tightly due to the spring force of the outwardly bowed strip side section 60 and the sharp edges of the cut-outs 45, and cannot inadvertently work loose from the pins 25a. If it is desirable to aid insertion over pins or to remove the buss strip 31, it is merely necessary to insert a simple tool (not shown) having a conical tip into the spreader probe hole 52 between the opposed edge surfaces of the section 36 to force the strip side sections 60 further apart from the fixed side sections 61. The grip of the locating and gripping cut-outs 45 on the pins 25a is thus released, permitting the strip 31 to be slipped over or raised upwardly off the pins 25a and 25b.

Referring to FIG. 4, the use of two such buss connectors 30 is illustrated. Here two connectors 30 sandwich an insulating layer of air between them and buss together different pairs of pins 25a or 25b; the upper connecting pins 25b and the lower 25a. A solid insulator could be substituted for air, making possible the same end result. Even with two buss connectors and an insulator, however, a very low profile is achieved.

Referring now to FIG. 5, a second form of the buss connector embodying features of the present invention is seen generally at 130. Like the buss connector 30 hereinbefore discussed, the buss connector 130 comprises an elongated flat strip 131 fabricated of a highly conductive alloy. The flat strip 131 is elongated alongside a row of terminal pins (not shown) and receives selected pins in corresponding patterned slots 135 formed in L-shaped projections 131a from the strip.

Each patterned slot 135 is preferably formed by die cutting or the like and includes a longitudinally extending slot section 136 open to the free end of the strip extension 131a. Intermediate the ends of the slot section 136 are formed a pair of pin locating and gripping cut-outs 145 whose configuration and dimension conform to those of the locating and gripping cut-outs 45 hereinbefore discussed in relation to the buss connector 30.

With the strip extension 131a formed to one side of the strip 131, it isn't necessary to aperture the strip 131 for receipt in unconnected relationship of those terminal pins to which it is not desirable to make a buss connection. In other respects, however, the connector 130 functions in a manner similar to that of the connector 30. The strip 131 is forced downwardly on the row of terminal pins, the pins entering the locating and gripping cut-outs 145 of the slots 136 until the strip rests on the bushings, 16, of the terminals. To facilitate easy removal of the strip, spreader probe holes might be provided in the slots 136, although they are not illustrated here.

FIGS. 6 and 7 illustrate third and fourth forms of the buss connector 230 and 330, respectively. They function in virtually the same manner as the second form illustrated in FIG. 4 providing, however, the pin connecting extensions 231a and 331a, respectively, in other forms of a strip. The strip 231, for example, comprises a series of rectangles designed to interconnect or buss together various terminals in two parallel rows of terminal pins. The strip 331 accomplishes the same end with a wider single strip configuration and outwardly projecting extensions 331a.

While several embodiments described herein are at present considered to be preferred, it is understood that various modifications and improvements may be made therein.

Claims

What is desired to be claimed and secured by Letters Patent of the United

1. An electrical buss connector for interconnecting a series of plate terminal wire-wrap pins arranged in a prescribed pattern, comprising:

a. an elongated, substantially flat metal strip,

b. a plurality of elongated slots formed in said strip in positions corresponding to the positions of selected ones of said pins,

c. each of said slots containing means between opposite ends of the slots for receiving and gripping a terminal pin,

d. said receiving and gripping means comprising cut-out means formed in each of the opposing edge surfaces of each of said slots,

e. said cut-out means together generally forming a rectangle having a dimension longitudinally of a corresponding slot which is slightly greater than the corresponding dimension of a terminal pin, and

f. the overall width of said cut-out means transversely of said slots normally being slightly less than the corresponding dimension of a

2. The electrical buss connector of claim 1 further characterized in that:

a. each of said elongated slots is open at one end to edge means of said flat metal strip whereby at least one section of said flat metal strip is resiliently movable in the plane of said strip to permit a terminal pin to be forced into said cut-out means and resiliently retained by said strip.

3. The electrical buss connector of claim 2 further characterized in that:

a. the terminal pin contacting edges of said cut-out means have sharp edges which are effective to wipe and clean a terminal pin to establish an excellent gas tight electrical connection between the pin and the strip.

4. An electrical buss connector for interconnecting a series of plate terminal wire-wrap pins in a prescribed pattern, comprising:

a. an elongated, substantially flat terminal strip,

b. a plurality of elongated slots formed in said strip in positions corresponding to positions of selected adjacent pairs of pins,

c. means in each of said slots between its ends for receiving and gripping one of a pair of adjacent terminal pins comprising cut-out means formed in at least one of the opposed edge surfaces of said slot, and

d. other means in each of said slots between its ends for receiving the other of each of said pairs of adjacent terminal pins without electrical contact being made between the pin and the strip comprising an enlarged

5. The electrical buss connector of claim 4 further characterized in that:

a. said elongated slots include a slot section extending longitudinally of said strip, and a perpendicular slot section connecting said first slot section with an edge of said strip at the opposite end of said slot whereby a section of said strip may resiliently bow outwardly of the body of said strip in the plane of said strip to receive and grip a terminal

6. The electrical buss connector of claim 5 further characterized in that:

a. said elongated slots include, between one cut-out means and said other cut-out means, means for receiving a probe to force said strip section away from the body of said strip and permit removal of said strip from the

7. An electrical buss connector for interconnecting a series of plate terminal wire-wrap pins arranged in a prescribed pattern, comprising:

a. an elongated, substantially flat metal strip,

b. a plurality of elongated slots formed in said strip in positions corresponding to the positions of selected ones of said pins,

c. each of said slots containing means between opposite ends of the slots for receiving and gripping a terminal pin, and

d. each of said slots being open at one end to a side edge of said flat metal strip whereby at least one section of said flat metal strip is resiliently movable in the plane of said strip to permit a terminal pin to be forced into said cut-out means and resiliently retained by said strip.

8. An electrical buss connector for interconnecting a series of plate terminal wire-wrap pins in a prescribed pattern, comprising:

a. an elongated, substantially flat terminal strip,

b. a plurality of elongated slots formed in said strip in positions corresponding to the positions of selected adjacent pairs of said pins,

c. means in each of said slots between its ends for receiving and gripping one of a pair of adjacent terminal pins,

d. other means in each of said slots between its ends for receiving the other of each of said pairs of adjacent terminal pins without electrical contact being made between the pin and the strip, and

d. each of said slots being open at one end to a side edge of said flat metal strip whereby at least one section of said flat metal strip is resiliently movable in the plane of said strip to permit a terminal pin to be forced into said cut-out means and resiliently retained by said strip.