[0001] The subject invention relates to electrical connectors for printed circuit boards,
and in particular to an electrical'connector assembly where printed circuit boards
may be positioned in parallel spaced arrangement, where the connectors are arranged
in close proximity to each other.
[0002] With the increased miniaturization of electrical components, particularly with such
items as lap top computers, a need has arisen in the market for a means of positioning
the printed circuit boards as close as possible to each other, without interfering
with the components which are mounted on either board. These printed circuit boards
are generally interconnected by way of mating electrical connectors mounted on each
board, one half of the electrical connection mounted on one printed circuit board,
while the mating half of the electrical connection is mounted to the other printed
circuit board. While reducing the height of each corresponding electrical connector
will in fact reduce the spacing between the boards, eventually a point is reached,
where the height of the connector can no longer be reduced.
[0003] The object of the invention then is to provide an electrical connector and an electrical
connection whereby two parallel mounted printed circuit boards are electrically connected
to each other and spaced as close as possible.
[0004] The object of the invention was accomplished by providing an electrical connection
comprised of at least two printed circuit boards parallel mounted one to the other
with one connection member electrically connected to a first printed circuit board,
and a second connection member electrically connected to a second printed board, the
first and second connection members being electrically connectable to electrically
connect the first and second printed circuit boards.
[0005] The connection is characterized in that the first printed circuit board includes
a recessed section on an inner surface of the one board, and the first electrical
connector member is positioned in the recessed section, with a lower surface of the
connection member being positioned below the inner surface of the first printed circuit
board. The first printed circuit board has electrical traces on the inner surface
and the first electrical connector includes electrical contact terminals extending
outwardly of an insulating housing of the first electrical connector, the contact
terminals having contact portions positioned above the lower surface of the first
electrical connector and the contact portions are electrically connected to the electrical
traces.
[0006] By providing a recessed section on the inner surface of the one board and by lowering
the first electrical connector member into the recessed section, the distance between
the top of the electrical and the inner surface of the printed circuit board has been
reduced, without sacrificing the size of the electrical connector member housing.
[0007] Embodiments of the present invention will now be described by way of example with
reference to the accompanying drawings in which:
Figure 1 shows a three dimensional view of the female portion of the electrical connector
of the present invention;
Figures 2 and 3 show alternate embodiments of the present invention to different embodiments
for mounting at various depths with.in the printed circuit board;
Figure 4 shows the terminal blank as stamped for use with any of the connectors showing
Figures 1 - 3;
Figures 5 - 7 show the terminal modifications to the blank of Figure 4 for use with
the connectors of Figures 1 - 3;
Figure 8 shows the male connector adapted for interconnection with any of connectors
shown in Figures 1 - 3;
Figure 9 shows an isometric view of the male tab terminal used in the connector of
Figure 8;
Figure 10 shows the male and female connector halves mounted to respective printed
circuit boards where the male and female connector halves are prepared for electrical
connection;
Figure 11 shows the two connector halves in electrical connection;
Figure 12 shows an isometric view of the underside of the two printed circuit boards;
and
Figure 13 shows an alternate embodiment for the female electrical terminal.
[0008] With reference first to Figure 1 the female connector is shown generally at 2 and
includes an insulating housing 4 having an upper mating face 6 with a plurality of
terminal passage ways 8. Opposed from each of the terminals passageways 8 are terminal
retaining apertures 10 as will be described in greater detail herein. The housing
4 also includes side walls 12 and end walls 14. A flange portion 16 extends around
the periphery of the side walls 12 and end walls 14 forming an upper platform surface
18.
[0009] It should also be noted as from Figure 1 that the flange portion has a vertical slot
therethrough forming edge surfaces 20 as will be described in greater detail herein.
As shown in Figure 1, the end faces 14 extend downwardly to a lower surface 22, the
lower face 22 being shown most clearly in Figure 12 as having laterally disposed slots
24.
[0010] With respect still to Figure 1, the female connector 2 includes a plurality of electrical
terminals 30 having opposed contact portions 32 disposed proximate to the upper face
6 and positioned within the passageways 8. As shown in Figure 1, the terminal passageways
8 are cruciform in shape, including portions 8a for receipt of the contact portions
32, and transverse portions 8b for receipt of mating tab portions, as will be described
herein. The terminals 30 further include locking legs 34 disposed in respective apertures
10. Each of the terminals includes a lower leg portion 36 in continuity with a surface
mount portion 38 having a lower surface 40 which can be positioned on a circuit pad
for soldering the connector to a printed circuit board. With respect now to Figures
4 - 7, the electrical terminal will be described in greater detail.
[0011] As shown first in Figure 7, the electrical terminal 30 includes opposed contact portions
32 where each of the contact portions are connected to first and second contact arms
42 and 44 where each of the contact portions are joined along a lower base portion
46. The base portion 46 is continuous with the lower leg portion 36 via a bight portion
48. The locking leg 34 extends vertically upwardly from the lower leg 36 and retains
the terminals 30 to the housing 4 as described above with reference to Figure 1. As
shown in Figure 7 the surface mount contact portion 38 also extends outwardly from
the lower leg portion 36.
[0012] As configured in Figure 1, the electrical connector 2 is suitable for mounting to
an electrical printed circuit board 50 as shown in either of Figures 10 or 12. As
shown in Figure 10, the electrical connector 2 is shown mounted to an electrical printed
circuit board 50, where the housing 4 projects through an opening 52 (Figure 12),
with the lower surface portions 40 of the surface mount legs 38 electrically interconnected
to circuit pads 54 (Figure 10) of the printed circuit board 50.
[0013] As shown in Figures 10 and 12, the electrical connector housing 4 is recessed below
an upper surface 56 of the printed circuit board which substantially reduces the vertical
distance y(1) between the upper mating face 6 of the housing 2 and the upper surface
56 of the printed circuit board. As mentioned above, it is desirable to reduce the
distance between parellel mounted circuit boards thus making it desirable to reduce
the vertical distance between the upper face of an electrical connector and the upper
surface of the printed circuit board. Thus, by recessing the electrical connector
into an aperture of the printed circuit board, this distance has been substantially
reduced as compared to electrical connectors which have either surface mount or through
hole mount electrical terminals extending through a lower face of the electrical connector
housing and where the housing is above the surface of the printed circuit board.
[0014] As shown in Figures 5 and 6, alternate electrical terminals are shown as 130 and
230 having corresponding features as that described with relation to Figure 7. As
shown in Figures 5 - 7, it should be appreciated that the connecting portions 37,
137 and 237 vary in vertical height which also varies the vertical position of the
surface mount contact portion 38, 138 and 238. By varying the electrical terminals
between those shown in Figures 5 - 7, the electrical connector can be configured as
shown in Figures 1 - 3.
[0015] For example the terminal shown in Figure 7 corresponds to the resultant connector
shown in Figure 1; the terminal shown in Figure 6 corresponds to the resultant connector
shown in Figure 2 while the electrical terminal shown in Figure 5 corresponds to the
electrical connector shown in Figure 3. It should also be appreciated then that by
varying the electrical terminals of the connector 4 as shown in Figures 1 - 3 or between
any variation thereof, the vertical distance y(1) as described earlier with respect
to Figure 10, which is the distance between the upper surface 6 of the housing and
the upper surface 56 of the printer circuit board, can be increased or decreased as
desired.
[0016] As shown in Figure 4, a uniform terminal stamped blank 31 is shown which can be used
to make any of the electrical terminals which correspond to Figures 5, 6 or 7. It
should be appreciated that a single terminal can be stamped and the appropriate surface
mount leg 38, 138 or 238 can be retained while the other unneeded portion can be discarded
by stamping that portion away.
[0017] As shown in Figure 8 a corresponding mating male connector is shown as 60 having
an insulative housing 62 comprised of end walls 64, side walls 66 and open upper face
68 forming an internal cavity, and a lower surface 70. The housing 60 further includes
two outer insulating ribs 72 having openings 74 therethrough, providing an appropriate
position for the position of electrical male contacts 80.
[0018] As shown most clearly in Figure 9, the electrical male terminals 80 include upper
tab portions 82 for electrical connection with the opposed contact portions 32 described
above, where the upper tab portions extend vertically upwardly from a lower base portion
84 which in turn are electrically connected to surface mount leg portions 86 via interconnection
portions 88. As configured in Figure 8, the lower leg portion 84 is positioned exterior
to the housing adjacent to the lower surface 70 of the housing 60 thereby positioning
the surface mount leg portion 86 exterior to the housing 60 along side the side walls
66 in a similar nature to the female connector 2 shown in Figure 1. It should be appreciated
then that the male tab contacts shown in Figure 9 could be varied as are the terminals
shown in Figure 5 - 7 by varying the interconnection portion 88 in length to raise
or lower the surface mount contact portion 86.
[0019] Thus as shown in Figure 12, the male electrical connector 60 is shown electrically
connected to a printed circuit board 90 where the housing 62 is shown recessed within
an aperture 82 of the printed circuit board. The surface mount contact legs 86 are
electrically connected to circuit pads 92 on the printed circuit board. Thus as shown
in the progression of Figures 10 and 11, the electrical connection system as described
above can be used to reduce the vertical dimension y(2) shown in Figure 11 between
the opposing printed circuit boards 50 and 90.
[0020] It should be appreciated that by varying the electrical terminals in accordance with
the teaching of the present disclosure that many different variable distances y(2)
can be achieved. It should also be appreciated that various printed circuit boards
can take on various architectures given the connector designs to complement the connector
designs. For example as shown in Figure 11, the female electrical connector 2 is shown
recessed below the printed circuit board 50. Thus low height electrical components
could be added to the lower surface 58 of the printed circuit board such that the
distance is not lost between the lower surface of the printed circuit board 58 and
the lower surface of the electrical connector, shown in Figure 11 as y(3). It should
also be appreciated that the real estate intermediate the surfaces 56 and 96 could
also carry various components such that this volume is not wasted.
[0021] Finally with respect to Figure 13, an alternate electrical terminal 330 is shown
which can be used in place of the electrical terminal 30 shown in Figures 47 in the
event that thermal expansion and retraction could be a problem. As shown in Figure
13 the terminal 330 includes a reverse spring arm 331 which is integral with either
of the contact arms 338 or 339. This reverse spring arm 331 allows for more movement
of the electrical connector without cracking the solder joint between the electrical
terminals and the electrical circuit pad on the printed circuit board. It should be
appreciated that this configuration could also be used on the male electrical terminals
shown in Figures 8 and 9.
1. A surface mount electrical connection comprised of a printed circuit board and an
electrical connector, the connection being characterized in that:
the printed circuit board (50,90) includes a recessed section (52,82) on an inner
surface (56,96) of said board, and said electrical connector member (2,60) is positioned
in said recessed section, with a lower surface (22,72) of said connector member (2,60)
being positioned below said inner surface (56,96) of said printed circuit board (50,90),
said first printed circuit board (50,90) having electrical traces (54,94) on said
inner surface (56,96), and said electrical connector (2,60) including electrical contact
terminals (37,137,237,337,88) extending outwardly of an insulating housing (4,62)
of said electrical connector (2,60), said contact terminals (37,137,237,337,88) having
contact portions (38,138,238,338,86) positioned above said lower surface (22,72) of
first electrical connector (2,60), said contact portions (38,138,238,338,86) being
electrically connected to said electrical traces (54,94).
2. An electrical connection in accordance with claim 1, characterized in that said recessed
section (52,82) is defined by an opening positioned completely through said printed
circuit board (50,90).
3. An electrical connection in accordance with claims 1 or 2, characterized in that said
connection includes two printed circuit boards (50,90), each having a connector member
(2,60) electrically connected thereto, both said first (50) and second (90) printed
circuit boards (50,90) have recessed sections, and both said first and second connector
members (2,60) have lower surfaces (22,72) positioned below inner surfaces (56,96)
of respective first and second printed circuit boards (50,90).
4. An electrical connection in accordance with claim 3, characterized in that said first
and second electrical connector members (2,60) have printed circuit board contact
portions extending from said lower surface (22,72), having upstanding leg portions
extending upwardly along side edges of said insulative housings, said leg portions
extending into foot portions which form the surface mount electrical connection portions
(38,138,238,338;86).
5. An electrical connection in accordance with claim 1, characterized in that said electrical
connector members (2,60) each include electrical terminals, where the electrical terminals
include mating contact portions (32,132,232;82) positioned within the insulative housing
(4,62), said electrical terminals extending through a lower surface of said housing,
said terminals including upstanding leg portions flanking side walls of said housing,
and feet portions extending from said leg portions, said feet portions being adapted
to overly said inner surface (56,96) of said printed circuit board (50,90), said feet
portions having edges (40) in contact with said electrical traces (54,94).
6. An electrical connection in accordance with any of claims 1-5, characterized in that
electrical components (C₁,C₂) are mounted to said inner surface of said printed circuit
board.
7. An electrical connection in accordance with claim 6, characterized in that electrical
components (C₁,C₂) are also electrically mounted on an inner surface of said second
printed circuit board.
8. An electrical connection in accordance with claim 7, characterized in that said lower
surface of said first electrical connection member (2,60) extends entirely through
said first printed circuit board.
9. A method of making the electrical terminals of claim 5, characterized by the steps
of:
(a) forming each electrical terminal with an elongate leg portion (37,137,237,337;88)and
a plurality of feet portions (38,138,238,338,339;86) extending from said elongate
leg portion, said leg portions extending horizontally from said leg portion at various
vertical positions along said leg portion, and
(b) selecting one of said vertical positions for said foot portions while selectively
removing said undesired foot portions, whereby the clearance between said first and
second printed circuit boards when in the connected position can be selectively varied.