Terminal strip with auxiliary support

A strip of interconnected edge clips for attachment to contact pads on a circuit-bearing board, in which a plurality of edge clips each have a free end and a stem end with the stem ends of the clips connected with a carrier rail or strip. A pair of spaced-apart spring fingers are on the free ends of the clips for receiving an edge of a circuit-carrying board therebetween, and an elongate auxiliary support strand extends past the free ends of the plurality of clips and is mechanically connected with the free ends of the clips to provide support to the clips. According to another aspect of the invention, the clip has an angularly extending interconnecting portion between the stem end and free end, offsetting the free end in both a sideward and rearward direction relative to the stem end.

BACKGROUND OF THE INVENTION 
1. Field of the Invention 
This invention relates generally to terminal clips or edge clips for 
attachment to a contact pad on a circuit-bearing chip or board. The clip 
is preferably of the type wherein solder is mechanically connected with 
the clip in a position to be melted for bonding the clip to the contact 
pad. More particularly, the invention relates to a strip of such terminal 
clips carried at one of their ends by a carrier strip, and wherein the 
free ends of the clips are supported by an auxiliary support, whereby a 
strip of such clips is securely supported in position while being attached 
to a circuit-bearing chip. 
2. Prior Art 
Various clips are known in the art wherein a quantity of solder is 
associated with the clip so that when the clip has been positioned on a 
contact pad of a circuit-bearing chip and the assembly heated, the molten 
solder covers the adjacent surfaces of the clip and pad to form, when 
cool, a metallurgical joint between the clip and pad. For instance, 
terminals of this type with various arrangements of solder-holding and/or 
pad-contacting fingers are disclosed in Seidler U.S. Pat. No. 4,120,558 
and U.S. Pat. No. 4,203,648, in each of which the body portion from which 
the fingers are formed is flat and wide enough so that each of the fingers 
will have adequate strength for its intended purpose. 
Increasing commercial pressure for miniaturization of the circuit bearing 
chips and the clips or terminals associated therewith requires reduction 
of the size and spacing (pitch) of the contact pads and the clips. Since 
the pads are fully supported by the material of the chip, no difficulty is 
encountered with the reduced spacing of the pads. However, the terminals 
or clips which are attached to the pads must have at least enough inherent 
strength to be self-supporting as they are applied, and to maintain good 
electrical contact with their respective pads while being soldered. 
Reduction in the size of the clips in order to accommodate the reduced 
spacing of the contact pads makes the clips relatively flimsy. It is not 
economical to increase the gauge of the strip from which the terminals or 
clips are stamped, since a very thin strip is electrically satisfactory. 
As the clips become smaller and more fragile, there is an advantage to 
having them carried at both ends during the manufacturing process. 
However, this is not always possible when the clips are severely formed. 
In order to overcome these problems, some manufacturers make the clips in 
discrete, short lengths and then form them. This procedure obviously 
increases the handling problems substantially, and makes such a process 
economically impractical. 
Further, in some applications, the clips have stem ends which are adapted 
to extend through holes in circuit boards. Miniaturization of the circuits 
results in the holes being spaced very closely together, with resulant 
thin walls and weakness between adjacent holes. 
SUMMARY OF THE INVENTION 
Accordingly, it is a principal object of this invention to provide a strip 
of interconnected clips for attachment to contact pads on a 
circuit-bearing chip, wherein auxiliary support is connected with the 
clips to support the free ends thereof. 
Another object of the invention is to provide a strip of interconnected 
terminal clips for attachment to contact pads on a circuit-bearing chip, 
wherein the clips are supported at both ends prior to forming and one end 
connection is then cut off, after which the part is formed to its final 
shape. When the final shape of the clip has been attained, the clips are 
crimped to an auxiliary support fed into the die, to support the 
relatively flimsy clips. 
A further object of the invention is to provide a strip of interconnected 
clips for attachment to contact pads on a circuit-bearing chip, wherein 
the clips have a free end and a stem end, the stem end being connected to 
a carrier strip and an auxiliary support strand being connected with the 
free ends to provide auxiliary support to the clips. 
Another object of the invention is to provide a plurality of terminal clips 
for connection between two circuit-bearing boards, wherein some of the 
clips have an angularly disposed interconnecting portion between the ends 
thereof to offset one end of the clip from the other end in both a 
rearward and sideward direction, so that the plurality of clips have one 
of their ends aligned, but the other ends of the plurality of clips are 
offset from one another to provide greater spacing between said other 
ends. 
These and other objects and advantages of the invention are achieved by 
providing a strip of interconnected clips each having one end connected to 
a carrier strip and a pair of string fingers on the other end thereof for 
receiving the edge of a circuit-bearing chip therebetween, and wherein one 
of the fingers is engaged in at least partially encircling relationship 
with a support strand of non-conductive material to support the clips as 
they are applied to the chip and soldered. If the support strand or 
filament is non-conductive and has a melting point higher than the melting 
point of the solder, the strand can be left on the device after the 
soldering operation. If it is desirable to remove the strand after 
soldering, a score mark can be provided in the clip to break out the 
strand-supporting part. In this event, the strand can be either conductive 
or non-conductive. 
In accordance with one particular aspect of the invention, a plurality of 
edge clips each have a free end and a stem end, and the stem ends of the 
clips are connected with a carrier strip. A pair of spaced apart spring 
fingers are on the free end of each clip for receiving an edge of the 
circuit-bearing chip therebetween, and an elongate auxiliary support 
strand extends past the free ends of the plurality of clips and is secured 
to the free end of each clip to provide auxiliary support for the clips. 
In accordance with another aspect of the invention, an edge clip for 
attachment to a contact pad on a circuit-bearing board, comprises a free 
end and an elongate stem end with a plurality of spring fingers on the 
free end for receiving an edge of a circuit-bearing board therebetween. 
The elongate stem end is adapted to extend through a hole in a 
circuit-bearing board, and an angularly disposed interconnecting portion 
is connected between the free end and the stem end, offsetting the free 
end in both a sidward and rearward direction relative to the stem end.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
A strip of interconnected clips is indicated generally at 10 in FIG. 1 and 
comprises a carrier strip 11 having spaced pilot holes 12 therein for 
indexing the strip through successive stamping operations in a power 
press, not shown, to form the clips. A plurality of uniformly spaced clips 
13 are carried by the strip 11 and comprise elongate bodies or stem ends 
14 integrally joined with one edge of the carrier strip 11. The free end 
of the clips 13 is formed with a pair of spaced apart spring fingers 15 
and 16, between which the edge of a circuit-bearing chip (not shown) is to 
be received. 
One of the fingers 16 partially encircles and securely grips a mass of 
solder 17, while the other finger 15 partially encircles and grips an 
auxiliary support comprising a continuous strand or filament 18, 
preferably of non-conductive material such as plastic or the like. Thus, 
as seen best in FIG. 1, the clips 13 are rigidly supported in uniformly 
spaced positions by means of the continuous strand 18 crimped to the free 
ends of the clips. 
The clips according to the invention are formed from blanks folded about 
longitudinal fold lines to define a narrow clip having relatively wide 
fingers and stem portions. 
As seen in FIG. 3, the spring finger 15 may have a fracture line 19 formed 
therein by a suitable notch or the like, whereby the spring finger and 
associated strand 18 may be separated from the clip after the clip is 
permanently attached as by soldering to a circuit-bearing chip. In this 
instance, the support strand 18 may be formed of a conductive material 
such as metal, if desired. 
A second modification of the invention is illustrated in FIGS. 4 and 5, 
wherein a plurality of clips 13' are carried by the carrier strip 11. The 
clips 13' have elongate stem ends 14' with stops or shoulders 20 formed 
near the upper ends thereof and are intended to extend through openings in 
a circuit-carrying board. Above the stops 20, the body of the clips 13' is 
bent at an intermediate interconnecting portion 21 in both a rearward and 
sideward direction so that the upper portion or free end 22 of each clip 
is offset both rearwardly and sidewardly relative to the stem ends 14'. 
The spring fingers 15 and 16 with the associated mass of solder 17 and 
continuous support strand 18, respectively, are formed on the upper body 
portion 22. 
Accordingly, as shown in FIG. 7, a circuit board 23 may have a plurality of 
holes 24 and 25 drilled therethrough in spaced, parallel rows adjacent an 
edge of the board, with the holes being spaced apart a distance of, for 
example, 0.100 of an inch. Then, if a plurality of clips 13 such as 
illustrated in FIG. 1 are inserted in the holes 25 in the back row, and a 
plurality of clips 13' such as illustrated in FIG. 4 are inserted in the 
holes 24 of the front row, the edge-engaging spring fingers 15 and 16 of 
the respective clips are in alignment with one another and the pitch or 
spacing between adjacent clips (0.050 of an inch in the example given) is 
only half as great as the spacing between adjacent holes. 
A further example of the invention is illustrated in FIG. 6, wherein the 
clip 13" is severely formed between the carrier strip 11 and the spring 
fingers 15' and 16'. While this clip can be supported initially on carrier 
strips at both ends, it would be necessary to separate the clip body from 
one of the carrier strips before carrying out the severe forming step to 
the body. The clip would then be flimsy and difficult to manage when 
applying to a circuit carrying chip. In accordance with the invention, the 
continuous support 18 can be crimped to the free ends of the clips to hold 
the clips rigid and in position for subsequent attachment to a circuit 
bearing chip. 
Therefore, in accordance with the present invention, it is possible to 
arrange the clips with pitches as small as 0.050 of an inch rather than 
0.100 of an inch as commonly used heretofore. The reduction in pitch is 
effected with no significant reduction in the material used in the clip 
and with ample spacing between the holes in which the stem ends of the 
clips are associated. Moreover, the clips may be severely formed between 
their ends and subsequently crimped to a continuous auxiliary support 
strand to rigidify the clips. 
It will thus be seen that the objects set forth above, among those made 
apparent from the preceding description, are efficiently attained and, 
since certain changes may be made in the above article without departing 
from the spirit and scope of the claims appended thereto, it is intended 
that all matter contained in the description and shown in the accompanying 
drawings shall be interpreted as illustrative and not in a limiting sense.