U.S. patent number 3,838,388 [Application Number 05/362,913] was granted by the patent office on 1974-09-24 for furcate contact.
This patent grant is currently assigned to Bunker Ramo Corporation. Invention is credited to Gerhard Bauerle, Oswald Hubner.
United States Patent |
3,838,388 |
Bauerle , et al. |
September 24, 1974 |
FURCATE CONTACT
Abstract
A furcate contact with at least two resilient contact arms. The
contact has a body portion supporting the contact arms which
converse toward one another adjacent the tip of the contact. Each
contact arm is concavely arched perpendicular to its longitudinal
axis and toward the opposite contact arm, the arched portion
extending over essentially the entire length of each contact arm.
In a preferred embodiment of the invention, each contact arm is
divided into two arched contact fingers, each of the fingers being
concavely arched perpendicular to its longitudinal axis and toward
the opposite finger.
Inventors: |
Bauerle; Gerhard (Willsbach,
DT), Hubner; Oswald (Neuenstadt, DT) |
Assignee: |
Bunker Ramo Corporation (Oak
Brook, IL)
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Family
ID: |
5846473 |
Appl.
No.: |
05/362,913 |
Filed: |
May 23, 1973 |
Foreign Application Priority Data
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May 31, 1972 [DT] |
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2226561 |
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Current U.S.
Class: |
439/857 |
Current CPC
Class: |
H01R
13/112 (20130101) |
Current International
Class: |
H01R
13/115 (20060101); H01r 013/12 () |
Field of
Search: |
;339/217,258,259 |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
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953,626 |
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Dec 1956 |
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DT |
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1,461,938 |
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Nov 1966 |
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FR |
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Primary Examiner: McGlynn; Joseph H.
Attorney, Agent or Firm: Lesser; N. Arbuckle; Frederick
M.
Claims
What we claim is:
1. A furcate contact for establishing a plurality of electrical
connections to a male contact comprising:
a body portion including opposite edges;
a pair of cantilever spring contact arms each having an integrally
formed portion on said body portion with one surface of each
integrally formed portion lying in a respective transverse plane
extending along a respective one of the opposite edges of said body
portion, said arms each extending longitudinally in one direction
from one end of said body portion toward each other arm and from
the respective transverse plane to locate the ends of said arms
spaced from said body portion in adjacent positions for receiving a
male contact between the ends of said arms spaced from said body
portion, a pair of spaced guiding fingers formed on each end of
each arm spaced from said body portion with each pair of fingers
formed in a direction extending from each other pair of fingers for
guiding said male contact for receipt between said arms;
each arm having a cross section defining an undulating curve
perpendicular to the longitudinal axis of the respective arm with
each undulating curve including a pair of end curves with each end
curve extending from a respective opposite edge of each arm and
formed along a radius of curvature extending from an axis spaced
adjacent a respective transverse plane; each finger having a cross
section defined by and continuous with a respective one of said end
curves defining the cross section of a respective arm; and
a curve for each arm intermediate each pair of end curves with each
intermediate curve formed along a radius of curvature having an
axis intermediate said arms whereby said arms and fingers are
substantially rigidified and the end curves of each arm provide at
least two positions of engagement with said male contact for
establishing a plurality of electrical connections to said male
contact in response to the receipt of said male contact between
said arms.
2. A furcate contact as claimed in claim 1 in which each guiding
finger extends toward the respective transverse plane with the
angle between said fingers less than 180.degree. and each
intermediate curve has a radius of curvature smaller than the
radius of curvature of the respective end curves.
Description
BACKGROUND OF THE INVENTION
1. Field of the Invention
The field of art to which the invention pertains is that of
electrical connectors, and more particularly electrical
receptacle-type contacts which are adapted to receive blade or pin
contacts for making electrical connection.
2. Description of the Prior Art
Prior art furcate contacts generally have contact arms which are
provided with opposing contact sections biased toward one another.
The contacting arms of the prior art contacts have a generally
rounded, elongated appearance. Modifications of basic prior art
receptacle-type contacts have been made for the purposes of
receiving both plate-like and pin-like mating connector plug
contacts. One such arrangement provides four protruding contact
arms arranged in pairs, one above the other. Another known
arrangement provides contact arms which are divided into two
contacting fingers in side-by-side relationship. In such
arrangements, both plate-like and pin-like connector plug contacts
can be received and guided into the receptacle. A variety of
disadvantages of such prior art arrangements, however, have been
demonstrated. The known configurations require careful insertion of
the contact plugs, making it difficult to insert the plug in the
central position of the receptacle. Further, close manufacturing
tolerances in the arrangement of the contact arms of the receptacle
and the mating contacts of the plug are encountered.
SUMMARY OF THE INVENTION
It is an object of the present invention to provide a furcate
contact of the above-described type which is of simple design,
facilitates the insertion of mating contacts, and assures good
electrical connection.
In accordance with the invention there is provided a contact
receptacle having contact arms which are concavely arched
perpendicular to the longitudinal axis and in the direction of the
opposite contact arm, the arched portion extending over essentially
the entire length of each contact arm.
One of the main advantages of utilizing concavely arched contact
arms is the fact that such construction results in improved
rigidity of the contact arms. Thus, with the same thickness of
material for construction of the contact, the length of the contact
arms can be increased. Moreover, the contact pressure with the
mating plug contact is increased, thereby enhancing the electrical
connection therebetween. These properties permit looser tolerances
for the manufacture of the contacts and hence reduce the production
costs. At the same time, an improved receptacle contact results
from the fact that they are not damaged when the mating plug
contact is inserted, even when the plug is not exactly positioned
in the center of the receptacle. Further, both plate-like and
pin-like mating contacts can be more readily inserted between the
arched contact arms than with the flat contact arms of prior art
devices.
Preferably, each of the opposing contact arms is formed having two
axially aligned parallel concavities extending in the same
direction, that is, toward the opposite contact arm. Such a
configuration again results in increased rigidity of the contact
and improved the guiding effect for receiving pin-like plug
connector contacts.
In one embodiment of the invention, each contact arm is divided
into two concavely arched contact fingers adjacent the free end of
each of the contact arms. The contact fingers are formed by
providing a slit extending from the free end of the contact arm
inwardly toward the body of the contact.
Since the increased rigidity of the contact arms and contact
fingers in accordance with the invention allows the application of
increased forces when mating contacts are inserted, the body
portion of the contact must also be sufficiently strong to accept
such forces. Thus, in a modification of the furcate contact of this
invention, the body portion is provided with a reinforcing
depression or dimple extending in longitudinal direction of the
contact in the area of the contact joining the arms and the body
portion.
BRIEF DESCRIPTION OF THE DRAWINGS
The invention will now be described in detail with reference to the
accompanying drawings representing preferred embodiments of furcate
contact according to the present invention. In the drawings:
FIG. 1 is a front elevation view of a furcate contact in accordance
with the invention.
FIG. 2 is a side elevation view of the furcate contact shown in
FIG. 1.
FIG. 3 is a cross-section of the furcate contact taken along the
lines 3--3 of FIG. 2.
FIG. 4 is a front elevation view of a second embodiment of a
furcate contact according to the invention.
FIG. 5 is a side elevation view of the furcate contact of FIG.
4.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
The furcate contact shown in FIGS. 1-3 is provided with a body
portion having a U-shaped carrier mid-section 1 leading
longitudinally into a flat resilient ridge 2 leading to a
connecting terminal end section 14 again having a U-shaped
cross-section. Two contact arms 4 extend longitudinally from and
are carried by the carrier mid-section 1, the two arms 4 facing one
another. One end of each arm 4 is integrally formed along a
respective edge 4a and 4b of the body portion with the juncture of
the edges of the upper surface of the body portion lying in a
common horizontal plane and one surface of the integrally formed
portion of each arm lies in a respective transverse plane extending
along a respective edge 4a and 4b of the body portion. The arms 4
each has a cantilever portion extending from the respective
transverse plane and longitudinally from one end of the body
portion toward each other arm to form cantilever spring arms to
locate the ends of the arms spaced from the body portion in
adjacent positions for receiving a male contact between the ends.
The two contact arms, beginning at the carrier mid-section 1,
extend inclined toward each other to the free end of the contact
arms 4. Adjacent the free end, the contact arms 4 are bent
outwardly at an obtuse angle, thereby forming end sections 12
having internal camming surfaces 15 adapted to readily position and
easily accept a mating pin or plate type plug contact.
As viewed in FIG. 2, each contact arm 4 may be provided with a slit
5 which extends from the free end of the contact arm 4 toward the
terminal end 14 over approximately one-third of the entire length
of the contact arm 4. Each slit 5 divides the end section of the
contact arm 4 into two contact fingers 6 bent in a direction from
each other with the angle between the fingers less than 180.degree.
to form guiding fingers for guiding a pin contact member between
the arms 4.
The cross-section of each contact arm 4 below the slit 5 is in the
form of a pair of parallel and adjacent concavely arched portions 7
which are arched perpendicular to the longitudinal axis of each of
the fingers 6. Each of the arched portions 7 has a width
approximately equal to that of a contact finger 6. The concave
portions extend over substantially the entire length of the contact
arm 4 and reach the area of the carrier mid-section 1. Below the
area of the slit 5 and in the area between the arched portions 7,
contact arm 4 is bent in a direction opposite to that of the arched
portions 7 and extends beyond the axis of the slit 5. This can best
be seen by reference to FIG. 3. It will be noted from FIG. 3 that
the arms 4 and fingers 6 each have a cross section forming or
defining an undulating curve perpendicular to the longitudinal axis
of the respective arm with each undulating curve including a pair
of end curves 7a. Curves 7a extend from a respective opposite edge
of each arm to a position intermediate the edges and each curve 7a
has a radius of curvature, whose respective axis, indicated by
dashed line 7b, is located adjacent the respective transverse plane
of the arm, which extends along a respective opposite edge 4a and
4b. A curve 7c is located intermediate each pair of end curves 7a.
The intermediate curve 7c, as seen in FIG. 3, has a radius of
curvature, indicated by dashed lines 7d, extending from an axis
located intermediate the arms and the radius is smaller than the
radius of curves 7a. The fingers 6 each have a cross section
defined by a respective one of the end curves 7a and continuous
with the respective end curve of the respective arm to stiffen the
fingers. When a male contact member is received between the arms 4,
as indicated by dashed lines 7e, the curved portions 7a provide at
least two points of engagement between each arm 4 and the pin or
blade contact, despite considerable variations in dimensional
tolerances.
In order to strengthen the mid-section 1 of the contact, a
depression or dimple 8 is formed on the rear side of the contact.
The dimple 8 makes rigid the otherwise resilient ridge 2.
A resilient catch 9 is provided on the carrier mid-section 1 so
that the downwardly bent end of catch 9 can be pressed into the
U-shaped carrier mid-section 1 upon insertion of the contact in a
terminal block.
FIG. 1 shows that the ridge 2 is provided with wings 10 extending
along both sides of ridge 2. At least one of the edge sections is
provided with a stop shoulder 11.
The furcate contact of FIGS. 4 and 5 differs from the embodiment
shown in FIGS. 1-3 in the shape of the carrier mid-section 1 and
the ridge 2. The other parts of the contact are unchanged and are
denoted by the same reference symbols as in FIGS. 1-3. No
protruding edges are provided at the ridge 2. However, the U-shaped
carrier mid-section 1 is provided with protruding lugs 13 in the
area adjacent the ridge 2. At least one of the lugs 13 is provided
with a stop shoulder 11.
From the foregoing, it can be readily realized that this invention
can assume various embodiments. Thus, it is to be understood that
the invention is not limited to the specific embodiments described
herein, but is to be limited only by the appended claims. For
example, it is within the scope of this invention that the contact
arms 4 not be provided with slits 5 and that each contact arm 4 may
only have a single concavely arched portion 7. Further, two
parallel concavely arched portions 7 can be provided in each arm 4
without a slit 5. The carrier mid-section 1 and the ridge 2 can
have uniform cross-sections over their entire lengths.
Additionally, the carrier mid-section 1 and ridge 2 may be
U-shaped, flat, or slightly arched, and the carrier mid-section 1
may be provided with a separate reinforcing dimple from that of the
ridge 2.
* * * * *