U.S. patent number 3,676,838 [Application Number 05/039,658] was granted by the patent office on 1972-07-11 for electrical connectors.
This patent grant is currently assigned to Essex International, Inc.. Invention is credited to Stephen J. Grebik, Marvin E. Hartz, Anthony J. Taormina.
United States Patent |
3,676,838 |
Hartz , et al. |
July 11, 1972 |
ELECTRICAL CONNECTORS
Abstract
An electrical connector assembly comprises a spherical or ball
terminal and a socket adapted to receive the ball and having a
substantially U-shaped configuration including a pair of opposed
sides or arms spaced apart a distance less than the diameter of the
ball, each of the arms having an opening therein of smaller
diameter than that of the ball. Preferably, each of the arms of the
socket has a slot which communicates with its associated opening,
each slot including an inwardly tapering throat portion which
functions to guide the ball terminal into the openings.
Inventors: |
Hartz; Marvin E. (Grosse Pointe
Farms, MI), Taormina; Anthony J. (Detroit, MI), Grebik;
Stephen J. (Roseville, MI) |
Assignee: |
Essex International, Inc. (Fort
Wayne, IN)
|
Family
ID: |
21906658 |
Appl.
No.: |
05/039,658 |
Filed: |
May 22, 1970 |
Current U.S.
Class: |
439/749;
439/857 |
Current CPC
Class: |
H01R
13/20 (20130101); H01R 13/432 (20130101) |
Current International
Class: |
H01R
13/20 (20060101); H01R 13/02 (20060101); H01R
13/428 (20060101); H01R 13/432 (20060101); H01r
011/22 () |
Field of
Search: |
;339/218,256,258,8,252,253 ;287/12,21,87,88,89
;24/23OF,23SL,21S,216,217 ;46/26,29 |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Leppink; James A.
Assistant Examiner: Hafer; Robert A.
Claims
We claim:
1. An electrical connector comprising a generally U-shaped socket
member adapted to receive a ball terminal and having a pair of
substantially parallel, spaced apart arms formed of resilient,
electrically conductive material joined by a web, each of said arms
having an opening therein, said openings being coaxial, each of
said arms having a slot extending inwardly of said arm and
terminating at the associated opening, said slots being parallel to
one another, each of said slots having confronting edges which
converge in a direction toward said opening and form a tapered
throat communicating with the associated opening, the spacing
between said arms, the diametral dimension of each of said
openings, and the width of each of said throats being less than the
diameter of a ball terminal adapted to be received by said socket
member.
2. The connector set forth in claim 1 wherein the opening in each
of said arms is located closer to a free edge thereof than to said
web.
3. The connector set forth in claim 2 wherein said web joins said
arms at the ends thereof remote from said free edges.
4. The connector set forth in claim 2 wherein said web joins said
arms at the sides thereof adjacent said free edges.
5. An electrical connector construction adapted to receive a ball
terminal comprising a body having at least one chamber therein,
said chamber having an access opening leading thereto; and a
conductive socket member accommodated in said chamber, said socket
member having a pair of substantially parallel, spaced apart arms
formed of resilient, electrically conductive material joined by a
web, each of said arms having an opening therein, said openings
being coaxial, each of said arms having a slot extending inwardly
of said arm and terminating at the associated opening, each of said
slots having confronting edges which converge in a direction toward
said opening and form a tapered throat communicating with the
associated opening, the spacing between said arms, the diametral
dimension of each of said openings, and the width of each of said
throats being less than the diameter of a ball terminal adapted to
be received by said socket member.
6. The construction set forth in claim 5 wherein said chamber has
spaced apart, opposed side walls adjacent said arms, each of said
arms being spaced from its adjacent side wall to permit flexing of
said arms toward and away from the adjacent side walls.
7. The construction set forth in claim 5 including resilient
fingers projecting from said arms toward and engaging said side
walls.
8. The construction set forth in claim 5 wherein said chamber has a
base snugly accommodating said web, said chamber having side walls
upstanding from said base and being substantially parallel to but
spaced from the adjacent arms to permit flexing of said arms toward
and away from the adjacent side walls.
Description
The invention disclosed herein relates to plug and socket type
connectors wherein the plug or pin has one or more round-head
terminals adapted to be accommodated in substantially U-shaped
sockets each of which includes a pair of resilient, spaced apart
spring arms between which the round head of a terminal may be
accommodated. Connectors of the kind disclosed are especially
adapted for the connection of switches to a circuit and for in-line
terminal connections, but have other uses as well.
Connector assemblies of the general class to which the invention
relates have been proposed heretofore, but not all of them have
been satisfactory for a number of reasons. For example, it is
possible with conventional pin and socket connector assemblies to
obtain a false or insecure coupling with the result that the pin
and socket separate in use. This problem is aggravated in those
instances in which the pin terminal must be engaged forcibly with
its socket, and particularly if the pin or the socket is somewhat
malformed or has burrs which prevent proper seating of the parts
without the application of excessive force. Even in those instances
in which pin type terminals fit perfectly within their sockets,
considerable care must be exercised to assure that the pins are
aligned axially with the sockets so as to avoid bending of the pins
or of the sockets. Conversely, it is equally important that
conventional pin and socket connectors be disassembled in such
manner as to avoid bending of the pins and sockets. As a
consequence, it frequently is impossible to connect or disconnect
the connectors of conventional design without rendering them
unsuitable for further use.
An object of this invention is to provide a pin and socket
electrical connector construction which overcomes the disadvantages
of prior constructions referred to above.
Another object of the invention is to provide pin and socket type
terminal connectors which fit together with a snap action which may
be felt by the assembler so as to avoid false or imperfect
connections.
A further object of the invention is to provide a connector
assembly of the character referred to wherein small imperfections
in the terminal parts have no effect on their assembly.
Another object of the invention is to provide a pin and socket
connector assembly wherein the pins may be seated in the sockets
without necessitating axial alignment thereof.
Another object of the invention is to provide a connector assembly
of the kind described which is simpler and more economical in
manufacture than similar constructions presently in use.
Other objects and advantages of the invention will be pointed out
specifically or will become apparent from the following description
when it is considered in conjunction with the appended claims and
the accompanying drawings, in which:
FIG. 1 is an isometric view of a switch casing provided with pin
terminals adapted to be seated in sockets carried by a base
member;
FIG. 2 is an enlarged, isometric view of a socket formed in
accordance with one embodiment of the invention;
FIG. 3 is a fragmentary, enlarged, side elevational view of the
base shown in FIG. 1, but with the wires omitted;
FIG. 4 is an enlarged, sectional view taken on the line 4--4 of
FIG. 1;
FIG. 5 is an exploded view of a pin terminal and socket member
constructed in accordance with another embodiment of the
invention;
FIG. 6 is a top plan view, on a reduced scale, of the apparatus
shown in FIG. 5 and in assembled relation, but with the wires
removed from the socket member; and
FIG. 7 is an end elevational view of the socket member shown in
FIG. 6.
The apparatus disclosed in FIG. 1 includes a switch casing 1 of
known construction have a non-conductive bottom 2 through which
projects a plurality of conductive pins 3 each of which terminates
at its free end in a round head or spherical ball 4 of uniform
diameter. Associated with the switch casing 1 is a base member 5
having a body 6 formed of electrically insulating material and
which is adapted to be secured to a support by means of screws (not
shown) which may pass through mounting ears 7. The body may be
provided with upstanding rails 8 between which the switch casing 1
may be accommodated.
Formed in the body 6 is a plurality of chambers 9 having an open
side or access opening. In communication with each chamber is a
tubular fitting 10 for the accommodation of an insulated conductor
11. Joined to each conductor 11 and accommodated in the associated
chamber 9 is a socket or terminal 12 formed of resilient, springy,
conductive material. It will be understood that the member 5 is
molded in place with the conductors 11 and the terminals 12 in
accordance with conventional molding techniques.
Each terminal socket 12 is generally U-shaped and has a pair of
substantially parallel arms 13 spaced apart from one another and
joined by a web 14. At one end of the walls 13 are tabs 15 which
may be rolled around the wire of the conductor 11 and additional
tabs 16 which may grip the insulation of the conductor 11 in the
conventional manner. At the opposite ends of the walls 13 the web
14 is extended to form a short tongue 17 which, in the molding of
the body 5, extends under a wall forming the associated chamber 9
so as to retain the socket 12 snugly within the chamber.
As is best illustrated in FIG. 4, each chamber 9 has a base 17 in
which the web 14 of the associated terminal 12 fits snugly and each
base 17 has shoulders 18 from which extend side walls 19 of the
chamber. Each of the terminal arms 13, therefore, is spaced from
the associated side wall 19 of its chamber.
Each of the arms 13 of the terminal 12 is provided with an opening
20 of generally circular shape, the center of each opening being
closer to the free edge of the arm than it is to the web 14. This
construction provides for a substantial beam length between the web
and the openings for a purpose presently to be explained. In
communication with each opening 20 is a slot 21, the sides 22 of
which converge in a direction inwardly from the free edge of the
arm 13 to form an inwardly tapering throat communicating with the
associated opening.
The spacing between the arms 13 of each terminal 12 is less than
the diameter of the terminal balls 4, and the diameter of each
opening 20 is less than the diameter of the balls 4. The difference
between the diameter of a terminal ball 4 and the spacing between
the terminal arms 13 need not be great, but the diameter of the
ball should be sufficiently large as to flex the arms 13 away from
one another to a noticeable extent in order to accommodate the ball
4 therebetween. The flexing of the arms 13 is possible because of
the resilience of the material from which the member 12 is made and
because of the spaces between the arms 13 and the sides 19 of the
chamber 9. The difference between the diameters of the ball 4 and
the openings 20 again need not be great, but the diameter of the
openings 20 should be sufficiently smaller than the diameter of the
ball 4 to assure gripping of the ball by the edges of the openings
when the ball is accommodated in the openings.
Inasmuch as the diameter of the ball 4 is greater than the spacing
between the terminal arms 13, the latter resists seating of the
ball in the openings 20. Such resistance is lessened by the slots
22. The resilience of the arms is sufficient to enable them to seat
on the ball with a snap action when the ball passes the narrowest
portion of the inlet throat leading to the openings 20, and such
snap action may be felt by the assembler.
When the ball is seated in the openings 20 any attempt to remove
the ball from the socket 12 necessitates spreading apart of the
arms 13. Although the ball terminal 4 may be removed from the
socket 12, the resistance of the arms 13 to being spread apart
requires the exertion of deliberate force on the terminals, thereby
avoiding the likelihood of inadvertent separation of the
terminals.
The embodiment of the invention disclosed in FIGS. 5-7 is similar
to the earlier described embodiment, but constitutes as in-line
connector assembly. In this embodiment a pin-type terminal 25 has a
shank 26 terminating at one end in a sphere or ball 27 and at its
opposite end is provided with tabs 28 and 29 for connection to the
component parts of an insulated conductor 11. The assembly also
includes a socket member 30 having a pair of arms 31 spaced apart
by a web 32 which terminates at its forward end in a locking tongue
33. At its opposite end the web 32 is provided with tabs 34 and 35
which may be secured to the component parts of another insulated
conductor 11.
Those edges of the arms 31 adjacent the web 32 are free and are
provided with generally coaxial, spherical openings 36. In
communication with each opening 36 is a slot 37, the opposite sides
38 of which converge inwardly from the free edges of the arms 31 so
as to provide an inwardly tapering throat leading to the openings
36. The diameter of the ball 27 is greater than the diameter of the
openings 36 and also is greater than the spacing between the arms
31.
The terminal 30 is adapted to be accommodated in a non-conductive,
tubular molded housing 39 provided with a chamber 40 in which the
arms 31 and the web 32 are accommodated, the housing 30 having an
opening 41 communicating with the chamber 40 for the accommodation
of the conductor 11. A shoulder 42 is provided between the chamber
40 and the opening 41 and the arms 31 carry outwardly directed
tangs or fingers 43 which seat against the shoulder 42 and thus
maintain the terminal 30 in in assembled relation with the housing
39.
The terminal 25 may be assembled with the terminal 30 by presenting
the ball 27 to the slots 37, whereupon the arms 31 will be spread
apart so as to permit the ball 27 to pass through the slots into
the openings 36. As the ball passes the narrowest portion of the
inlet throat, the arms 31 will spring back toward one another with
a snap action which may be felt by the assembler. The edges of the
openings 36 will grip the opposite sides of the ball 27 securely,
thereby assuring good electrical connection and preventing
inadvertent separation of the terminals 25 and 30.
A particularly advantageous characteristic of connectors
constructed in accordance with the invention is that the pin
terminals may be presented to their sockets without first being
precisely aligned therewith. This characteristic is illustrated in
FIG. 1 wherein the pin terminals 3 supported by the switch casing 1
may be coupled to the socket members 12 by rotary movement of the
body 5 in the direction of the arrow 44. As the member 1 is rotated
toward seating relation, the ball terminals 4 will be presented to
their respective socket members 12, whereupon the slots 21,
together with the converging edges 22, automatically will guide the
balls 4 into proper seating relation with their respective
terminals 12. In like manner, presentation of the ball terminal 27
to the housing 39 need not require precise alignment of the ball 27
with the terminal 30 inasmuch as the slots 37 and the tapering
walls 38 will guide the ball 27 into proper seating relation
between the arms 31.
Another advantage of the disclosed construction is that movement of
the pin terminal into the socket terminal effects wiping of the
parts, thereby assuring good electrical connection.
The location of the ball-accommodating openings of the socket
terminals should be such that there is a substantial distance
between the web of the socket and the closest edge of the openings.
This provides a substantial beam length between the openings and
the web so as to effect better distribution of flexing forces
applied to the arms upon movement of the ball terminal into and out
of the socket terminal.
Inasmuch as the socket terminals of the disclosed construction
basically are U-shaped in configuration, they can be manufactured
by considerably simpler and less expensive dies than are utilized
in the manufacture of cylindrical or other socket members.
The disclosed embodiments are representative of presently preferred
forms of the invention, but are intended to be illustrative rather
than definitive thereof. The invention is defined in the
claims.
* * * * *