U.S. patent number 3,646,504 [Application Number 04/867,178] was granted by the patent office on 1972-02-29 for electrical connector.
This patent grant is currently assigned to Litton Systems, Inc.. Invention is credited to Edwin O. Classon.
United States Patent |
3,646,504 |
Classon |
February 29, 1972 |
ELECTRICAL CONNECTOR
Abstract
An electrical connector for printed circuit boards consisting of
a series of contact members each having a curved contact section
extending into the recess in an insulating block of generally
cubical shape in which the printed circuit board is inserted and an
external section provided with an integral terminal portion. The
metallic contact member is in the form of an open loop and, being
resilient, is mounted about the outer surface of the insulating
block by spreading the ends of the loop to clear the locking
protuberance formed on the bottom of said block. The curved contact
section of the contact member forms a beam, the lower end of which
is free to move as the beam is deformed by the insertion of the
printed circuit board, and the pressure on the board contact or
terminal decreases as the beam is deflected. As the circuit board
is inserted into or withdrawn from the connector, the wiping action
provides for good contact surfaces on the opposing contacts, and
the withdrawal force required is greater than the force required to
insert the circuit board in the connector.
Inventors: |
Classon; Edwin O. (Wallingford,
CT) |
Assignee: |
Litton Systems, Inc. (Beverly
Hills, CA)
|
Family
ID: |
25349283 |
Appl.
No.: |
04/867,178 |
Filed: |
October 17, 1969 |
Current U.S.
Class: |
439/188;
439/637 |
Current CPC
Class: |
H01R
12/721 (20130101) |
Current International
Class: |
H05r 001/07 () |
Field of
Search: |
;339/17L,17LC,17LM,17F,17M,176M,176MP,176MF,217R,217S,256R
;29/630,413,418,423 |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
Other References
Reliable Electrical Connectors, 1958, page 188. .
"Switching Connector," IBM Tech. Disclosure, N. K. Perkins, Vol. 7
No. 6, November 1964, page 424..
|
Primary Examiner: Champion; Marvin A.
Assistant Examiner: Staab; Lawrence J.
Claims
What is claimed is:
1. A multiple contact connector, comprising:
an insulating block of generally cubical shape having a central
recess with inside surfaces for receiving a conductor bearing
terminal board;
a plurality of planar contact members each in the form of an open
loop having upper and lower arcuate end portions disposed on
opposite ends of a straight intermediate portion;
separate end portions extending from said upper arcuate end
portions disposed inside said recess;
said block being grooved to position said contact members side by
side on the outside surface of said block and said block having
rounded upper and lower protuberances about which said upper and
lower arcuate end portion snap for removably retaining said contact
members thereon;
the inside end portions of each contact member being arched at the
point of contact with said terminal board to provide a positive
wiping contact with the conductors thereon; and
offset end portions connected to said arched inside end portions
having sliding contact with said inside surface of said recess for
supporting said arched inside end portions and for further
removably retaining said contact members upon said block.
2. A multiple contact connector according to claim 1, in which said
contact members are removably retained in position on said
insulating block by the four point spring contact thereof including
the contact of the offset end portions connected to said arched
inside end portions, the contact of said upper arched portions
about said upper rounded protuberances, the contact of said
straight intermediate portions along said outside surface of said
insulating block, and the contact of said lower arcuate portions
about said lower rounded protuberances.
3. A multiple contact connector according to claim 2, in which the
contact members are arranged in two rows with the inside end
portions thereof mounted on opposite inside surfaces of the central
recess in said insulating block, and the arched sections of at
least one opposing pair of contacts are in electrical contact when
the terminal board is removed from the connector.
4. A multiple contact connector, comprising:
an insulating block of generally cubical shape having a central
recess of rectangular cross section opening into the top face of
said block to receive a terminal board;
said block having rounded protuberances on at least one upper and
lower outside edge thereof adjacent to and opposite the opening of
said central recess;
contact members on said insulating block;
said contact members each including an arched contact section
extending within said recess;
a flattened end portion extending from said arched contact section
of each contact member within said recess for slidable contact with
the inside surface of said recess when the arched contact section
of the contact member is depressed by the insertion of a terminal
board in said connector;
said contact members each including an open loop having upper and
lower arcuate portions engaging said upper and lower rounded
protuberances on said block joined by a straight intermediate
portion, wherein said upper and lower arcuate portions and said
flattened end portions removably snap assemble said contact members
in place upon said block.
5. An electrical connector, comprising;
an insulating cubical block with inner surfaces forming a recess in
an upper surface, side surfaces, a lower surface, and rounded
protuberances at the jointure of said upper and lower surfaces with
said side surfaces;
contact members to be removably mounted upon said insulating
block;
said contact members each including:
an end portion slidably engaging said inner surfaces of said
insulating block of the electrical connector;
an arched portion integral with said end portion;
a curved portion integral with said arched portion engaging said
rounded protuberance at the jointure of said upper surface and side
surface;
a straight intermediate portion integral with said curved portion
engaging said side surface;
a second curved portion integral with said intermediate portion
engaging said rounded protuberance at the jointure of said lower
surface and said side surface thereby interacting with said first
mentioned curved portion for demountably securing said contact
member to said insulating block through the four point contact
therewith of said end portion, first curved portion, intermediate
portion and second curved portion; and
a terminal end portion integral with said second curved portion of
the contact member.
6. A multiple contact connector according to claim 4, additionally
comprising:
a skirt section in the form of a flat plate integral with one end
of said contact members beyond said lower arcuate portions for
supporting said contact members in accurate alignment and for snap
assembling said contact members in said insulating block; and
said contact members being scored adjacent the point of attachment
to said skirt section to facilitate separation of the contact
members from said skirt section after said snap assembling for
permitting individual disassembly of said contact members.
Description
BACKGROUND OF THE INVENTION
The invention relates to a multiple contact connector, particularly
adapted for making a low resistance electrical connection to the
conductors or terminals of an electrical unit such as a printed
circuit board. Since these connectors are often made in small
sizes, the mounting and replacement or assembly of the small
contact members offer problems which the present invention is
designed to overcome.
BRIEF DESCRIPTION OF THE DRAWINGS
Referring to the drawings,
FIGS. 1 and 2 are plan and side views, respectively, drawn to an
enlarged scale of a printed circuit board connector embodying the
invention;
FIG. 3 is a sectional perspective view of the connector shown in
FIGS. 1 and 2;
FIG. 4 is a detailed perspective view of the individual contact
member;
FIG. 5 is a detailed view of a modified form of contact member
adapted for the connector shown in FIGS. 1-3;
FIG. 6 is a view similar to FIG. 3, illustrating a modification
wherein the connector is provided with a switching contact; and
FIGS. 7 and 8 are top and side elevational views of an array of
contacts formed from a sheet metal blank, in one preferred step of
the manufacture.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring to FIGS. 1-3 of the drawings, the invention is shown by
way of example as embodied in a connector for a printed circuit
board or similar terminal board. The connector comprises an
insulating block 10 of generally cubical shape having a central
recess II to receive a printed circuit board 12, the connector
being shown about three times actual size (of one type) in FIGS. 1
and 2. The contact members 15 are supported on one or both sides of
the insulating block, which is provided with ridges 16 forming
parallel grooves in which the contact members are disposed. In a
subminiature connector, the spacing between contacts may be only a
few thousandths of an inch. The insulating block is rounded at the
points 17, 17a at the mouth or top of the recess 11 and provided
with protuberances or outwardly projecting ridges 18, 18a at the
bottom edges opposite the mouth of the recess 11.
As shown more clearly in FIG. 4, each contact member 15 is in the
form of an open loop located in a single plane and having a
straight intermediate section 20, curved or arcuate sections 21 and
22 shaped to fit snugly against the insulating connector block 10
at the points 17, 17a and 18, 18a, an arched convex section 23
terminating in an offset or flattened tip 24 at one end of the
contact member, and a terminal or solder tip 25 at the other end of
the contact member. The terminal part 25 of the contact member is
shown as perforated at the point 26 to receive a conductor or
connecting lead. Since the contact member is external instead of
being provided with a termination projecting through an opening in
the bottom of the insulating block, obviously the terminal end may
assume any desired shape. Furthermore the difficulty encountered in
forming the holes in the connector block in the case of a miniature
connector is avoided. The connector block may be molded
economically in very small sizes.
The connector may be provided with bused or redundant contact
members 20a as shown in FIG. 5. The contact member 20a consists of
a pair of contact elements similar to the contact member 15
connected together by an integral end portion 28.
The contact members 15 are made of resilient metal and are mounted
on or removed from the connector block 10 by spreading the ends of
the contact loop until the curved section 22 can be snapped over
the ridge or protuberance 18, 18a. The contact member is retained
in position by positive contact with the block at the points 17,
17a and 18, 18a, and on the outer surface of the block, while
allowing for complete freedom of movement of the arched contact
section 23 of the contact member. This feature of the invention
permits easy assembly, and also removal and replacement of
individual contact members if required for field repair.
The shape and arrangement of the contact portion of the contact
member 15 constitutes another important feature of the invention.
As the terminal board 12 (see FIG. 6) is inserted in the connector,
the convex or arched section 23 of the contact member is deflected
and the offset or flattened tip 24 slides along the inner surface
30 of the recess 11. While the desired wiping action of the contact
surfaces is obtained, the force applied to the conductors on the
printed circuit board is lower than with the usual type of contact,
and uniformity of the contact pressures from one contact to another
is assured since the forces do not depend upon the usual preset
contact configuration. In addition, the applied normal force or
contact pressure decreases as the board is inserted, while adequate
contact is maintained when the unit is subjected to vibration.
Furthermore the friction between the board and connector contacts
increases the withdrawal force required to remove the board from
the connector, compared to the insertion force.
The deflection characteristic of the arched contact section 23 of
the contact members allows the use of switching contacts in the
connector. Thus as shown by the dotted lines 23a in FIG. 6, one or
more pairs of opposed contacts may be so shaped as to make
electrical contact when the printed circuit board is withdrawn from
the connector.
As shown in FIGS. 7 and 8, in manufacture a plurality of contact
members 15 may be punched from a metal sheet 33 with an integral
skirt section 34. The blank is scored at the points 36 and 37 and,
after shaping the contact members, the tip ends 35 are broken off.
The contact members may then be inserted in the connector block 10
while attached to the skirt 34, which is then separated by flexing
the blank at the score line 36. This facilitates assembly,
especially in the case of a small connector having minute delicate
contact members.
It will be apparent that the invention provides a construction
having outstanding advantages in respect to the form and
arrangement of the improved contact members and the ease of
assembly and replacement of the contact members in the insulating
block. Individual contacts can be replaced without disturbing the
other contacts. The invention provides complete flexibility of
design in respect to contact spacing and termination, and for
connectors to be used with either single-sided or double-sided
printed circuit boards.
* * * * *