U.S. patent number 3,894,784 [Application Number 05/378,101] was granted by the patent office on 1975-07-15 for plug connector for a printed circuit board.
This patent grant is currently assigned to TRW Inc.. Invention is credited to Antony Brasher Clewes.
United States Patent |
3,894,784 |
Clewes |
July 15, 1975 |
Plug connector for a printed circuit board
Abstract
An electrical plug connector for a printed circuit board which
has electric circuits and edge connection pads on both sides of the
board includes an insulating moulding 10 having a spine portion 11
and a conjoining plug portion 12, and electrical contact fingers 21
which are secured in through-holes 14 in the spine portion, have
hooked plug ends 25 which engage in slots 18, 19 formed in the free
end of the plug portion, lie in shallow slots 17 on the plug
portion, and have at the other side of the spine portion free ends
30 set to resiliently engage with and be soldered to edge
connection pads on a printed circuit board. The spine portion has
end extensions which carry clamping bands 13 for enabling the
connector to be firmly secured to the edge portion of a printed
circuit board. The plug part of the moulding and the associated
hooked plug ends of the contact fingers 21 are intended to simulate
the edge of a two-sided printed circuit board to which the
connector is to be connected, so that a conventional socket
connector can be used therewith.
Inventors: |
Clewes; Antony Brasher
(Nottingham, EN) |
Assignee: |
TRW Inc. (Cleveland,
OH)
|
Family
ID: |
10347283 |
Appl.
No.: |
05/378,101 |
Filed: |
July 11, 1973 |
Foreign Application Priority Data
|
|
|
|
|
Jul 14, 1972 [GB] |
|
|
33007/72 |
|
Current U.S.
Class: |
439/629;
439/637 |
Current CPC
Class: |
H01R
12/725 (20130101) |
Current International
Class: |
H05k 001/07 () |
Field of
Search: |
;339/17F,17L,17LC,17LM,15B,151B,176MF,176MP,217S,156 |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
Primary Examiner: Frazier; Roy D.
Assistant Examiner: Staab; Lawrence J.
Attorney, Agent or Firm: Cohen, Esq.; Lawrence S.
Claims
I claim:
1. An electrical plug connector for a printed circuit board which
has electric circuits and associated edge connection pads on at
least one side of the board comprising
an electrical insulating moulding having a spine portion for
disposition adjacent an edge of such a printed circuit board, and a
plug portion extending from the spine portion on one side thereof
for disposition remotely from such an edge of a printed circuit
board, and having a transverse thickness substantially equal to
that of the edge of the printed circuit board, with which it is
adapted to be used,
the spine portion having a greater transverse thickness than the
plug portion, and two transversely spaced rows of through-holes,
which rows of holes open adjacent the plug protion on opposite
sides respectively of the plug portion, the holes in each row being
spaced apart along the length of the moulding and the outer wall of
each through hole having a recess forming an abutment therein
facing away from the plug portion and,
the plug portion having at its free end two transversely spaced
rows of slots, the slots in each row being positioned along the
length of the moulding in alignment with the respective
through-holes which open on the same side of the plug portion,
and
a plurality of resilient strip, electrical contact fingers mounted
on the plug connector in two parallel rows each comprising a median
fastening part, a hooked plug and part extending from the median
part at one end thereof, and a printed circuit board contacting
free and part extending from the median part at the opposite end
thereof,
each contact finger having its median part extending through and
fixed in one of the said through-holes in the moulding adjacent the
outer wall and having an abutment in detent contact with the
abutment in the outer wall and the contact having sets therein,
proximate to the plug side of the spine portion, to cause the part
of the contact finger lying adjacent the plug portion to lie snugly
in the appropriate one of shallow grooves in the surface of the
plug portion, its hooked plug end part engaged in an associated one
of the said slots at the free end of the plug portion of the
moulding, and its free end part extending from the spine portion of
the moulding and at least one of the rows of contact fingers
converging toward the opposite row of contact fingers to provide a
reduced space between them for resiliently receiving between them a
printed circuit board having a transverse thickness greater than
the space between them for guiding a printed circuit board between
the rows whereby to make electrical connection with an edge
connection pad of a printed circuit board when the connector is
presented to an edge part thereof,
the said plug portion of the moulding and the contact fingers
together simulating the edge of such a printed circuit board.
2. An electrical plug connector according to claim 1, wherein the
plug portion of the moulding has a longitudinal rib at its free
end, which rib lies between the two rows of slots and projects
beyond the extremities of the hooked plug end parts of the contact
fingers.
3. An electrical plug connector according to claim 1, wherein the
spine portion has longitudinal end extensions which extend beyond
the ends of the plug portion, and wherein clamping means carried on
each said end extension enable the connector to be secured in
position on an edge part of a printed circuit board after
positioning thereon with the said free end parts of the contact
fingers resting in electrical contact with adjacent edge connection
pads formed on the board.
4. An electrical plug connector according to claim 1, wherein each
through-hole in the spine portion of the moulding has a T-shaped
transverse cross section having a broad part in which is carried
the associated strip contact finger, and a narrow part extending
inwardly from the broad part towards a central part of the spine
portion.
5. An electrical plug connector according to claim 4, wherein each
slot in the free end of the plug portion of the moulding extends
from the said free end towards the spine portion, and has a
T-shaped transverse cross-section having a broad part in which the
hooked plug end of the associated contact finger is inserted, and a
narrow part extending outwardly from the broad part towards the
contact finger.
6. An electrical plug connector according to claim 1, wherein the
spine portion has longitudinal end extensions which extend beyond
the ends of the plug portion, and wherein clamping means carried on
each said end extension enable the connector to be secured in
position on an edge part of a printed circuit board after
positioning thereon with the said free end parts of the contact
fingers resting in electrical contact with adjacent edge connection
pads formed on the board.
7. An electrical plug connector according to claim 6, wherein each
through-hole in the spine portion of the moulding has a T-shaped
transverse cross section having a broad part in which is carried
the associated strip contact finger, and a narrow part extending
inwardly from the broad part towards a central part of the spine
portion.
8. An electrical plug connector according to claim 7, wherein each
slot in the free end of the plug portion of the moulding extends
from the said free end towards the spine portion, and has a
T-shaped transverse cross-section having a broad part in which the
hooked plug end of the associated contact finger is inserted, and a
narrow part extending outwardly from the broad part towards the
contact finger.
Description
This invention relates to an electrical plug connector for a
printed circuit board.
Some present day printed circuit boards are of considerable size,
and hence of considerable value. Circuits carried on such a board
make connection with external circuitry by means of plug and socket
connection means. Some printed circuit boards have circuits which
end adjacent an edge of the board in connection pads with which
external circuit connection is made by means of socket devices
which mate directly with the edge of the board, and which have
resilient contacts which make contact with the aforesaid connection
pads. These connection pads can be damaged by repeated application
and removal of such socket devices, so that ultimately a board can
no longer be used simply because of the inability to make good
electrical connection with the damaged connection pads.
According to the present invention an electrical plug connector for
a printed circuit board which has electric circuits and associated
edge connection pads on both sides of the board comprises
An electrical insulating moulding having a spine portion for
disposition adjacent an edge of such a printed circuit board, and a
plug portion extending from the spine portion on one side thereof
for disposition remotely from such an edge of a printed circuit
board, and having a transverse thickness substantially equal to
that of the edge of the printed circuit board,
The spine portion having a greater transverse thickness than the
plug portion, and two transversely spaced rows of through-holes,
which rows of holes open adjacent the plug portion on opposite
sides respectively of the plug portion, the holes in each row being
spaced apart along the length of the moulding, and
The plug portion having at its free end two transversely spaced
rows of slots, the slots in each row being positioned along the
length of the moulding in alignment with the respective
through-holes which open on the same side of the plug portion,
and
A plurality of resilient strip, electrical contact fingers each
comprising a median fastening part, a hooked plug end part
extending from the median part at one end thereof, and a printed
circuit board contacting free end part extending from the median
part at the opposite end thereof,
each contact finger having its median part extending through and
fixed in one of the said through-holes in the moulding, its hooked
plug end part engaged in an associated one of the said slots at the
free end of the plug portion of the moulding, and its free end part
extending from the spine portion of the moulding whereby to make
elecrical connection with an edge connection pad of a printed
circuit board when the connector is presented to an edge part
thereof,
the said plug portion of the moulding and the contact fingers
together simulating the edge of such a printed circuit board.
Preferably, the plug portion has a plurality of parallel shallow
grooves in each of its longitudinal faces, and the plug end parts
of the contact fingers lie in those grooves; and the plug portion
of the moulding has a longitudinal rib at its free end, which rib
lies between the two rows of slots and projects beyond the
extremities of the hooked plug end parts of the contact
fingers.
According to another preferred feature of the present invention the
spine portion of the moulding has first abutment means formed in
outer parts thereof which define the respective outer boundaries of
the respective through-holes, and each contact finger is shaped so
that its median part bears resiliently against the said outer part
of the through-hole in which it is located and has second abutment
means thereon arranged to engage with the aforesaid first abutment
means in the through-hole whereby to locate and secure the contact
finger in that hole.
Preferably, each through-hole in the spine portion of the moulding
has a T-shaped transverse cross section having a broad part in
which is carried the associated strip contact finger, and a narrow
part extending inwardly from the broad part towards a central part
of the spine portion; and each slot in the free end of the plug
portion of the moulding extends from the said free end towards the
spine portion, and has a T-shaped transverse cross-section having a
broad part in which the hooked plug end of the associated contact
finger is inserted, and a narrow part extending outwardly from the
broad part towards the contact finger.
The spine portion may have longitudinal end extensions which extend
beyond the ends of the plug portion, and clamping means carried on
each said end extension which enable the connector to be secured in
positon on an edge part of a printed circuit board after
positioning thereon with the said free end parts of the contact
fingers resting in electrical contact with adjacent edge connection
pads formed on the board.
One edge connector according to the present invention for a printed
circuit board having electric circuits and edge connection pads on
both sides thereof will now be described by way of example and with
reference to the accompanying drawings, drawn to an enlarged scale,
in which:
FIG. 1 shows a front view of the connector;
FIG. 2 shows a plan view of the connector;
FIG. 3 shows a vertical section taken on the line III--III of FIG.
1;
FIGS. 4, 5 and 6 show respectively front, plan and underside views
of a moulding incorporated in the connector; and
FIG. 7 shows a vertical section taken on the line VII--VII of FIG.
4.
Referring now to the drawings, the connector comprises an
electrically-insulating moulding 10 of a thermoplastic moulding
material, such as polycarbonate material, and having a spine
portion 11 and a conjoining plug portion 12. Lengthwise the spine
portion extends beyond the plug portion and carries at its ends
clamping bands 13 for securing the connector firmly to an edge part
of a printed circuit board, as will be explained later.
Whereas the plug portion has a transverse thickness which
corresponds to the thickness of a printed circuit board to which
the connector is to be secured, the spine portion has a greater
thickness and projects on both sides of the plug portion. The spine
portion has formed therein two longitudinally-extending rows of
spaced parallel holes 14 of T-shaped cross-section, which holes
open on to the respective longitudinal faces 15, 16 of the plug
portion.
From these holes shallow parallel grooves 17 extend along the
respective longitudinal faces 15, 16 of the plug portion, and
terminate at the free end of the plug portion in slots 18, 19 which
extend towards the spine portion and have T-shaped cross-sections.
A nose rib 20 extends along the length of the plug portion and
separates the slots 18, 19 from one another.
Carried within the holes 14 in the spine portion 11 are phosphor
bronze contact fingers 21 which are located in those holes by
anti-withdrawal and location projections 22 and 23 respectively,
which projections engage in appropriately shaped recesses formed in
the outer wall parts 24 of the spine portion.
Each contact finger has a hooked end part 25 which engages in, and
is secured against movement by, one of the T-shaped slots 18, 19 at
the free end of the plug portion. Sets in each contact finger at
26, 27 cause the part of the contact finger lying adjacent the plug
portion of the moulding to lie snugly in the appropriate shallow
groove 17, and the median part of the finger to lie adjacent the
outer wall part 24 of the spine portion.
Two further sets at 28, 29 in the parts of the contact fingers
which protrude from the free end of the spine portion cause those
parts of each pair of contact fingers to converge and to have
divergent tip parts 30. The spacing of the tip parts from one
another is such as to cause them to apply a positive pressure to
the appropriate connection pads on the printed circuit board when
the connector is secured thereon.
The connector is assembled simply by inserting the contact fingers
21 in the holes 14 of the spine portion, and guiding them so that
their hooked ends 25 enter the appropriate slots 18, 19 on the
respective sides of the nose rib 20. Each contact finger is finally
positioned when the anti-withdrawal and location projections 22, 23
engage in their respective recesses.
The sets are then made in the contact fingers at 28 and 29, and the
connection is completed by securing around the ends of the spine
portions the clamping bands 13.
To affix the connector to a printed circuit board the connector is
placed with the divergent tip parts of the contact fingers adjacent
the edge of the printed circuit board, and pressure is applied to
ease the contact finger tip parts and the clamping bands on to the
respective surfaces of the board. The connector is secured by bolts
passed through holes in the clamping bands and circuit board, and
nuts tightened on the bolts.
The electrical connection of the contact finger tip parts and the
connection pads of the printed circuit board is completed by a
soldering process.
The plug connector is thereafter ready for use, and has the merit
that it can cooperate with socket connectors which have hitherto
been used to mate directly with the edge of the printed circuit
board. Furthermore, the plug connector has the merit that it lies
in the same general plane as the printed circuit board, and demands
no greater separation of adjacent printed circuit boards than that
is required by other pertinent considerations.
* * * * *