U.S. patent number 3,670,288 [Application Number 05/115,358] was granted by the patent office on 1972-06-13 for torsion contact zero-insertion force connector.
This patent grant is currently assigned to AMP Incorporated. Invention is credited to William Robert Evans.
United States Patent |
3,670,288 |
Evans |
June 13, 1972 |
TORSION CONTACT ZERO-INSERTION FORCE CONNECTOR
Abstract
Disclosed is a connector for receiving the edge of a printed
circuit board, ceramic substrate or other circuit boards of the
like. The connector contains a plurality of pre-twisted contacts
that are untwisted for zero-force insertion of a circuit board
after which they are released to return toward their original
position making electrical contact with such board.
Inventors: |
Evans; William Robert
(Hummelstown, PA) |
Assignee: |
AMP Incorporated (Harrisburg,
PA)
|
Family
ID: |
22360872 |
Appl.
No.: |
05/115,358 |
Filed: |
February 16, 1971 |
Current U.S.
Class: |
439/269.1;
439/79 |
Current CPC
Class: |
H01R
12/88 (20130101) |
Current International
Class: |
H01R
12/16 (20060101); H01R 12/00 (20060101); H01r
013/62 () |
Field of
Search: |
;339/74,75,176 |
References Cited
[Referenced By]
U.S. Patent Documents
|
|
|
3526869 |
September 1970 |
Conrad et al. |
3553630 |
January 1971 |
Scheingold et al. |
|
Primary Examiner: McGlynn; Joseph H.
Claims
What is claimed is:
1. A connector for receiving a printed circuit board, ceramic
substrate, or the like comprising an elongated box-like structure,
a plurality of elongated contacts communicating between a top wall
and a bottom wall of said connector, said contacts having their
elongated dimension generally aligned along a first longitudinal
plane, each said contact being twisted about its elongated
dimension, a portion of each contact intermediate the upper and
lower ends thereof being generally parallel with a first lateral
plane generally normal to said first longitudinal plane, contact
portions at said upper end of each said contact being parallel with
a second lateral plane that is at an angle to said first lateral
and first longitudinal planes, movable means engaging said contact
near said upper end for imparting torsional movement to said upper
end, and actuating means engaging said movable means whereby
torsional movement can be imparted to said contact upper end to
twist it to a position generally parallel with said first lateral
plane.
2. A connector as claimed in claim 1 wherein said movable means
includes at least one elongated rack-type member having a plurality
of slots in one side thereof, each slot receiving one of said
contacts, said rack-type member being slidable in a path parallel
to said first longitudinal plane and said first lateral plane.
3. A connector as claimed in claim 2 wherein said contact portions
each include plural contact faces, said faces of each contact
engaging a single circuit on a circuit board or substrate received
by said connector.
4. A connector as set forth in claim 3 wherein said contact portion
has a blade-like configuration with opposite sides being contact
faces for mating with a slot.
5. A connector as set forth in claim 3 wherein said contact portion
has an offset two prong fork configuration with contact faces in
parallel offset planes for mating with a blade.
6. A connector as set forth in claim 3 wherein said actuating means
includes a gear member in toothed engagement with mating teeth on
one end of said rack-type member, said gear member concentrically
located on a shaft.
7. A connector as set forth in claim 3 wherein said actuating means
includes a first rectangular aperture in said connector housing and
an underlapping and misaligned second rectangular aperture in said
rack-type member, whereby insertion of a bevel-ended rectangular
tool through said first aperture into said second aperture will
move the second aperture into alignment with said first aperture
thus moving said rack-type member.
Description
BACKGROUND OF THE INVENTION
Common in the art today are many connectors for receiving the edges
printed circuit boards, ceramic substrates, and/or other such
circuit boards. These connectors generally fall into one of two
types; the contact is forced against the circuitry on the board
after insertion of the board or forced away from the board for
insertion of the board, then allowed to spring back into contact
with circuitry on the board. In both of these examples each contact
moves in a generally single-plane cantilever fashion. These
movements require space on either side of the circuit board for
such contact movement. This space requires a relatively wide
connector housing which, in todays high density packaging
requirements, is unsuitable. Moreover, the individual contacts
require exact spacing tolerances which limits the connector designs
to relatively wide contact-to-contact spacing. Currently 0.050 inch
center-to-center is the practical minimum spacing commonly
available for non-precision off-the-shelf use.
The most common drawback of the prior art devices is the relatively
long distance of insertion of the circuit board to make
contact.
BRIEF DESCRIPTION OF THE INVENTION
To overcome the above limitations of the prior art applicant has
invented a connector wherein the contacts have their contact
portions twisted about the elongated axis of the contact. Prior to
insertion of a circuit board, which has slots in the edge or
contacts connected to the circuitry thereon, the connector contact
faces are untwisted, the circuit board is inserted, and the contact
faces allowed to twist back toward their position of rest to engage
the circuit board contact or slot. In this manner, rather than
resting against a surface, the contact faces are restrained within
a slot or contact. In this manner misalignment can be compensated
for by cantilever bending of the contacts which still allows full
torsion action to take place. Moreover, with torsion action, a very
small insertion distance is traveled by the circuit board.
It is therefore an object of the invention to provide a connector
having a narrow width suitable for high density packaging.
It is another object of the invention to provide a connector
wherein precision spacing of contacts on 0.025 inch centers or less
is easily attainable.
A still further object of the invention is to provide a connector
for zero-force insertion of a circuit board wherein electrical
connection is made by the torsion memory of the connector
contacts.
Yet another object of the invention is to provide a connector
wherein the insertion distance of a circuit board is very
small.
Other objects and attainments of the present invention will become
apparent to those skilled in the art upon a reading of the
following detailed description when taken in conjunction with the
drawings in which there are shown and described illustrative
embodiments of the invention; it is to be understood, however, that
these embodiments are not intended to be exhaustive nor limiting of
the invention but are given for purposes of illustration in order
that others skilled in the art may fully understand the invention
and the principles thereof and the manner of applying it in
practical use so that they may modify it in various forms, each as
may be best suited to the conditions of a particular use.
IN THE DRAWINGS
FIG. 1 is a partial perspective view of one embodi of the invention
with contact faces in position to receive the shown circuit
board;
FIG. 2 is a section view taken along line A--A of FIG. 1 showing
the contact faces in position to receive the circuit board;
FIG. 3 is a partial section view taken along line A--A of FIG. 1
showing the circuit board in position but prior to release of the
contacts;
FIG. 4 is a diagrammatic section view taken along line B--B of FIG.
3;
FIG. 5 is a diagrammatic view similar to FIG. 4 but showing the
contact in its released position;
FIG. 6 is a section view taken along line C--C showing the contact
and actuating bar in position for receiving a circuit board;
FIG. 7 is a sectional view similar to FIG. 6 but showing the
contacts in their relaxed position;
FIG. 8 is a perspective view of a second embodiment of the
invention showing a double rack actuation with a blade contact;
FIG. 9 is a section view taken along line D--D of FIG. 8 showing a
gear and rack actuating mechanism;
FIG. 10 is a partial perspective view similar to FIG. 8 but showing
a narrow width contact suitable for mating with the ceramic
substrate shown;
FIG. 11 is a partial section view also taken along line F--F of
FIG. 8 showing the contacts in their circuit board mating position;
and
FIG. 12 is a partial view similar to FIG. 9 but showing the
contacts in position for receiving a circuit board.
Looking now at FIG. 1 the first embodiment of the invention is
shown. The connector 10 is an elongated box-like structure having
flanges 12 with apertures 14 extending from either end for purposes
of mounting to a mother circuit board, panel, or the like. The
housing has generally upright side walls 16 and end walls 18,
horizontal top wall 20 and bottom wall 22.
Located generally centrally between the two side walls 16 is an
elongate channel 24 (see also FIGS. 2,3,6, and 7) ending near the
top wall 20 in a cavity or recess 26 of a size and shape to receive
a printed circuit board 28, or the like. The lower end of channel
24 ends as at surface 30 (FIG. 2) with a plurality of slots 32
extending therefrom to a lower cavity or recess 34. Located within
channel 24 are a plurality of contacts 36 of a number equal to the
number of slots 32 with each contact having a terminal portion
extending into cavity 34 and a contact portion extending into
cavity 26.
The contacts 36 have their elongated axes parallel and aligned in a
first longitudinal plane 38. With primary reference to FIGS. 2,3,
and 4 each contact 36 is of a wide, flat width relative to its
thickness. The contacts are thin enough whereby 0.025 inch
center-to-center spacing is easily obtained and 0.010 to 0.015 inch
center-to-center spacing is well within design limitations. Each
contact is manufactured from a suitable electrically conductive
material as is known in the art. Each contact 36 has a terminal
portion 40 which in the instant embodiment is a cylindrical barrel
suitable for receiving a wire conductor therein to be crimped or
suitable for being received by a mating aperture in a mother
circuit board or the like. These terminal portions 40 are
alternately offset to achieve close spacing of contacts and may
take any of several configurations common in the art.
The contact 36, at an intermediate portion 42 (FIG. 1), has ears 44
extending from either side. This portion, with ears 44, is parallel
to a first lateral plane. Near the upper end or contact portion 46
a tab 48 extends to the left (FIG. 2). The contact portion
comprises an offset two prong fork configuration 48 having a pair
of prongs 50 (see also FIGS. 4 and 5) each with a contact face
52.
These contacts have their intermediate portions 42 in slots 32 with
the right ear 44 (FIG. 2) extending into a notch 54 which prevents
vertical movement of the contact. The left ear is located in an
elongated channel 56 located in movable wall 58. The tabs 48 are
located in individual slots 60 between which are teeth 62. Opposite
tab 48 teeth 64 extend one each between the contacts.
The teeth 62 from slots 66 therebetween for receiving the edge of
the contact portion. In its position of rest each contact portion
46 including tab 48 is parallel to a second lateral plane which is
at an angle both to the first lateral plane and the first
longitudinal plane. The two portions lying in different planes is
achieved by pre-twisting the contact during the manufacture thereof
after which it is placed in the housing. The twisting is confined
to the area between portions 42 and 46.
The moveable wall is slidable in the direction of arrows E in FIGS.
6 and 7. As seen also in FIGS. 6 and 7, and FIG. 1, wall 58 is held
in alignment by dowel pins 68 or the like which are received in
aperture 70 of the connector housing. Wall 58 has an apertured slot
72 at each end for receiving pins 68, the slot allowing for limited
sliding movement of wall 58. Also located in the housing through
top wall 20 is a rectangular aperture 70 which is aligned with
aperture 74 in the bottom wall 22. This aperture 74 need not extend
through the wall 22 but need only be a cavity or may not be
necessary at all. Offset from aperture 70 in wall 58 is a similar
rectangular aperture 76 (FIG. 7). When an appropriately bevel-ended
rectangular tool 78 (shown in phantom in FIG. 1 and in FIG. 6) is
inserted into aperture 70 and on through aperture 76 the wall 58 is
forced to the position of FIG. 6 with teeth 62 causing contact
portions 46 to torsion or twist into positions where they are
generally parallel to the intermediate portions 42. In this
position a circuit board 28 may be inserted into the connector with
zero force with each blade contact 80 inserted between offset
prongs 50 (FIG. 4). These contacts 80 have fingers 82 suitably
connected to respective circuitry on board 24, such as by
soldering. After insertion of the board the tool is removed
allowing the contact portions 46 to return toward their position of
rest causing contact faces 52 to engage blade contacts 80 (FIG.
5).
Turning now to the second embodiment illustrated in FIGS. 8 - 12
there is shown a connector 84 of a generally elongated box-like
configuration having top 86, bottom 88, side 90, and end walls 92
with side walls 90 parallel to a first longitudinal plane. A
plurality of contacts 94 are fixedly located in the housing bottom
wall 88 with the elongated center lines of the contacts being
parallel to and oriented in the afore-mentioned first longitudinal
plane (see FIG. 12) which is common with the connector's
longitudinal centerline G.sub.L . These contacts extend into a
cavity 96 formed by the side and bottom walls. The contacts each
have a terminal portion 98 parallel to a first lateral plane and a
contact portion 100, which includes laterally extending ears 102
and contact faces 104, and which is parallel to a second lateral
plane at an angle to the first longitudinal and first lateral
planes. To achieve this construction the contacts are pre-twisted
during manufacture prior to placement in the housing.
Located in a channel 106 in each of the side walls and facing the
cavity is a rack-type member 108 having slots 110 therein for
receiving ears 102. The rack-type members at one end have teeth 112
thereon for engagement with a gear 114. The gear is concentrically
carried on a shaft 116 having a slot 118 in the end for receipt of
a tool blade (not shown) such as a screw-driver. In the position of
FIG. 9 the contacts 94 are in their normal relaxed twisted
position. In FIG. 12 the gear 114 and rack-type member 108 are
actuated to twist the contact portions 100 to a position of
parallelism with the afore-mentioned first lateral plane thus
allowing for zero-force insertion of the circuit board 120. Circuit
board 120 has edge contacts similar to those of FIGS. 1 and 4.
After insertion of the circuit board the tool is removed and the
contacts are allowed to relax as in FIG. 11. The circuit board
contacts 122 are engaged by the contact faces 104 and prevent the
contact portion 100 from assuming its position of FIG. 9 thus
ensuring adequate contact force.
The variation of contact shown in FIG. 10 is a narrower width
contact more suitable for engaging the slotted edges 124 of a
ceramic substrate 126. Each interior face of slot 124 is a
continuation of respective circuitry 128 on the substrate. Blade
contact is made similar to that of FIG. 11.
It will, therefore, be appreciated that the aforementioned and
other desirable objects have been achieved; however, it should be
emphasized that the particular embodiments of the invention, which
are shown and described herein, are intended as merely illustrative
and not as restrictive of the invention.
* * * * *