U.S. patent number 3,831,129 [Application Number 05/397,243] was granted by the patent office on 1974-08-20 for deflectable jumper strip.
This patent grant is currently assigned to Thomas & Betts Corporation. Invention is credited to William G. Frey.
United States Patent |
3,831,129 |
Frey |
August 20, 1974 |
DEFLECTABLE JUMPER STRIP
Abstract
A jumper strip for terminal blocks or the like comprises in one
embodiment a pair of fastener engaging portions coupled together by
a resiliently deflectable upstanding arched portion so that the
spacing between the apertures may be selectively varied by exerting
suitable pressure on the arched portion. The strip may be disposed
over terminal screws having a center to center spacing slightly
greater or smaller than the spacing between the apertures in the
strip whereby upon release of the arched portion the strip is urged
against the shank of the terminal screws and retained in position
during the loosening and tightening of the screws. In another
embodiment, a plurality of such fastener engaging portions are
resiliently joined one to another in strip fashion to provide a
multiple terminal shorting bar or jumper strip. The apertures are
joined to a common edge of the jumper strip by a slot which may be
aligned with or offset from the axis of the aperture.
Inventors: |
Frey; William G. (Union,
NJ) |
Assignee: |
Thomas & Betts Corporation
(Elizabeth, NJ)
|
Family
ID: |
23570400 |
Appl.
No.: |
05/397,243 |
Filed: |
September 14, 1973 |
Current U.S.
Class: |
439/513 |
Current CPC
Class: |
H01R
9/2458 (20130101) |
Current International
Class: |
H01R
9/24 (20060101); H01r 031/08 () |
Field of
Search: |
;339/19,222,242,22,252
;24/81B,81CC,87TB |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Gay; Bobby R.
Assistant Examiner: Hafer; Robert A.
Attorney, Agent or Firm: Teschner; David Woldman; Jesse
Claims
The embodiments of the invention in which an exclusive property or
privilege is claimed are defined as follows:
1. A deflectable jumper strip comprising: a body member formed from
generally flat, resilient metallic stock, said body member having a
pair of generally flat fastener engaging portions lying in a common
first plane and coupled together by at least one resiliently
deflectable upstanding arched portion having sides extending
generally parallel to a second plane which is disposed
substantially perpendicular to said first plane, said arched
portion being disposed intermediate said fastener engaging
portions, there being an aperture extending transversely through
each of said fastener engaging portions, said apertures having
centers spaced a first given distance from one another when said
arched portion is in an undeflected state, and a second given
distance from one another when said arched portion is selectively
deflected, there being a slot joining each of said apertures with a
common edge of said jumper strip, the axis bisecting each of said
slots and lying in said first plane being selectively offset from
an axis parallel to said slot bisecting axis and passing through
the center of a corresponding one of said body member apertures and
lying in said first plane so that by selectively deflecting said
body member arched portion, said slots may be aligned with and
cooperatively coupled to terminals disposed on centers spaced from
one another a distance generally equivalent to said first given
distance, wherein upon the release of said arched portion, said
apertures are caused to be aligned with and cooperatively coupled
to such terminals, said slots thereby restricting the removal of
said jumper strip from such terminals prior to redeflection of said
arched portion.
2. A deflectable jumper strip as defined in claim 1 wherein the
center to center distance between said aperture is less than the
center to center distance between said corresponding slots.
3. A deflectable jumper strip as defined in claim 1 wherein said
fastener engaging portions are coupled together by two of said
arched portions.
Description
BACKGROUND OF THE INVENTION
1. Field of the Invention
The invention is directed to the field of interconnecting means for
terminal blocks and the like.
2. Description of the Prior Art
In many cases it is desired to bridge two or more terminals on a
terminal block or the like to provide a common electrical
connection thereto. This may be accomplished either by the use of
conventional wires connected to each of the desired terminals by
twisting a portion thereof around each of the shanks of such
terminals, or by the use of a solid shorting bar suitably apertured
to correspond to the spacing between the terminals to be shorted or
connected together. The former method is quite tedious and time
consuming and requires the unwrapping of the wire from the terminal
post to open or otherwise interrupt such connection. In the latter
case, the strips must be formed with slotted apertures having a
center to center spacing corresponding to the spacing between the
terminals to be shorted or connected. Thus, where differently
spaced terminals are employed a rather large quantity or stock of
such shorting strips must be maintained to ensure the proper fit in
any particular case. Additionally, when assembling such prior art
strips to a terminal block or the like, the strip must be
continuously supported in the desired position against the shank of
the terminal screws to be connected or shorted together until the
heads of the screws or threaded fasteners have been brought into
sufficient contact with the strip to hold the strip in the desired
position. Where such terminal block is disposed in a generally
vertical plane in an electrical assembly or the like, extreme care
must be exercised when loosening the terminal screws or fasteners
to disengage the strip therefrom to avoid having the strip fall
away from the terminal block and contact electrically energized
terminals or elements adjacent thereto. Attempts to avoid this
problem by supplying an unslotted aperture in the jumper strip
causes additional inconvenience in that the terminal screws must be
completely removed from the terminal block to provide for the
assembly or disassembly of the strip to and from the terminal
block.
SUMMARY OF THE INVENTION
The invention overcomes the problems and limitations noted above
with respect to prior art devices by providing a deflectable jumper
strip which is more reliable, convenient, efficient, and safer than
such prior art devices. The strip is formed with a resiliently
deflectable upstanding arched portion disposed intermediate each
two apertured fastener engaging portions each having apertures
spaced from one another a first given distance when the arched
portion is undeflected and a second given distance when the arched
portion is either compressed or expanded in response to a force
applied thereto. The strip may thus be employed to bridge two or
more terminals whose center to center spacing corresponds generally
to the deflected spacing between the apertures in the strip by
subjecting the arched portion to a suitable force to cause the
slots in the jumper strip to be aligned with the shank portion of
the threaded fasteners in the terminal block or the like. The strip
may thus be urged against the terminals and snapped into place
wherein upon removal of the force on the arched portion of the
jumper strip the strip will tend to return to its undeflected state
causing the side walls of the fastener receiving apertures to bear
tightly against the terminal block screws. The jumper strip is thus
maintained in position throughout the tightening and loosening of
such terminal block screws so that the loss or displacement of such
strip is effectively and simply prevented. The slots joining the
apertures in the strip to a common edge of the strip may either be
aligned with the apertures or offset therefrom which, in the latter
case, will tend to further lock the strip onto the terminal block
or the like. The degree of force required to selectively deflect
the arched portion of the jumper strip may be readily controlled by
varying the height, width, and physical configuration of such
arched portion thereby effectively controlling the resiliency
thereof. It is therefore an object of this invention to provide an
improved jumper strip.
It is a further object of this invention to provide a deflectable
jumper strip for interconnecting terminals of a terminal block or
the like.
It is another object of this invention to provide a self-locking
jumper strip.
It is yet a further object of this invention to provide means for
deflectably varying the spacing between the fastener engaging
apertures of a jumper strip.
Other objects and features will be pointed out in the following
description and claims and illustrated in the accompanying drawings
which disclose, by way of example, the principle of the invention
and the best mode contemplated for carrying it out.
BRIEF DESCRIPTION OF THE DRAWINGS
In the Drawings
FIG. 1 is a top plan view of a deflectable jumper strip constructed
in accordance with the concepts of the invention.
FIG. 2 is a front elevational view of the device of FIG. 1.
FIG. 3 is a fragmentary top plan view of a terminal strip which may
be employed in conjunction with the device of FIG. 1.
FIG. 4 is a fragmentary top plan view showing a method of
assembling the device of FIG. 1 to the terminal strip of FIG.
3.
FIG. 5 is a fragmentary top plan view showing the device of FIG. 1
assembled to the terminal strip shown in FIG. 3.
FIG. 6 is a fragmentary top plan view showing a further embodiment
of a deflectable jumper strip constructed in accordance with the
concepts of the invention.
FIG. 7 is a fragmentary front elevational view of the device of
FIG. 6.
FIGS. 8 and 9 are top plan views of further embodiments of a jumper
strip constructed in accordance with the concepts of the
invention.
Similar elements are given similar reference characters in each of
the respective drawings.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Turning now to FIGS. 1 and 2 there is shown a resiliently
deflectable jumper strip 20 constructed in accordance with the
concepts of the invention. For electrical applications, the strip
20 may be manufactured preferably from electrically conducting flat
resilient metallic stock stamped or formed essentially in the shape
shown. As illustrated, the strip 20 comprises a body member 22
comprising a pair of generally flat fastener engaging portions 24,
26 respectively, joined together by an upstanding resiliently
deflectable arched portion 28. The arched portion 28 may be
deflected outwardly or inwardly as shown for example, by the dotted
outlines 30 and 32, respectively, in FIG. 2 either manually or by
the use of a suitable tool (not shown). Each of the fastener
engaging portions 24, 26 comprises a fastener receiving aperture
34, 36, respectively. Joining each of the apertures 34, 36 to a
common edge 38 of the strip 20 is a slot 40, 42, respectively. In
the embodiment illustrated in FIGS. 1 and 2, the bisecting axes of
the slots 40, 42 shown respectively as 44, 46, are each offset from
the center line of its associated fastener receiving aperture 34,
36 by a distance shown as T1, T2, respectively, the distance T3
between the axes of the respective slots 40, 42 being shown in this
case as greater than the distance T4 between the centers of
fastener receiving apertures 34, 36. The arrangement may, of
course, be reversed wherein the distance T4 between the centers of
the adjacent apertures is greater than the distance T3 between the
axes of the respective slots. Consequently, the strip 20 may be
disposed adjacent a pair of terminals 48, 50 (See FIG. 3) attached
to a terminal block 52, the terminals 48, 50 being disposed on
centers spaced apart, for example, a distance equal to T4, and
urged into engagement with the terminals 48, 50 by deflecting the
arched portion 28 inwardly so that the sides thereof approach one
another as shown, for example, by the dotted outline 32 whereby the
axes 44, 46 defining the respective centers of the slots 40, 42 are
brought into coincidence with the shanks of the terminals 48, 50 so
that the terminals may be advanced freely through the slots 40, 42
and into engagement with the fastener receiving apertures 34, 36.
By releasing the arched portion 28, the strip 20 tends to assume
its original shape thereby locking the strip 20 against the
terminals 48, 50. The terminals 48, 50 may then be tightened down
to more securely hold the strip 20 thereto. To disengage the strip
20 from the terminal block 52 it is then merely necessary to loosen
the terminal screws 48, 50 and deflect the arched portion 28
inwardly until the slots 40, 42 coincide with the spacing between
the terminals 48, 50 whereby the strip 20 may then be urged out of
engagement with the terminals. As illustrated in FIG. 5, the
assembly of the strip 20 to the terminals 48, 50 provides a direct
connection therebetween and due to the locking action provided
enables the user to loosen each of the terminal fasteners 48, 50 to
insert further conductors thereunder, if necessary or desirable,
while being assured of the continued engagement of the strip 20
with the terminals 48, 50, during this operation. The relationship
between the slots 40, 42 of the strip 20 and the terminal screws
48, 50 of the terminal block 52 prior to the assembly of the strip
to the board is shown more clearly in FIG. 4. By providing a
relatively large opening between the slots 40, 42 and the common
edge 38 of the strip 20, which edge 38 tapers smoothly as at 54, 56
(FIG. 1) to the necked down portion of the slot 40, 42, the
assembly of the strip 20 to the terminals 48, 50 may be
accomplished in an alternative manner, that is, by urging the strip
20 against the terminal screws 48, 50 in a direction indicated by
the arrow 58 in FIG. 4 whereby the pressure of the tapered surfaces
54, 56 against the shank of the screws 48, 50 will cause the
fastener engaging portions 24, 26 to be urged towards one another
due to the resiliency of the arched portion 28 therebetween so that
the terminal screws 48, 50 may enter the slots 40, 42 in the strip
20 and be advanced to the fastener receiving apertures 34, 36 at
which time the strip 20 will tend to spring outwardly to its
original state causing the strip 20 to be locked to the terminal
screws 48, 50 as described hereinabove. By reversing the offset
relationship between the fastener receiving apertures 34, 36 and
the slots 40, 42, that is, where the distance between the axes 44,
46 of the slots 40, 42, respectively, is less than the distance
between the centers of the fastener receiving apertures 34, 36, the
outer edges of the slots 40, 42 bear against the shank of the
respective screws 48, 50 causing the fastener receiving portions
24, 26 of the strip to be deflected away from each other during
assembly of the strip to the terminal block and then returned to
their original state after the shank of each of the screws 48, 50
has entered its respective fastener receiving aperture.
Referring now to FIGS. 6 and 7 there is shown a further embodiment
of a deflectable jumper strip 60 constructed in accordance with the
concepts of the invention. The strip 60 may be of almost any length
and comprises a plurality of preferably similarly dimensioned
fastener receiving apertures 62 disposed in alignment along a
common longitudinal axis, each of the fastener receiving apertures
62 being joined to a common edge 64 of the strip 60 by a slot 66
having smoothly tapering sides 68, 70. Between each pair of
fastener receiving apertures 62 extending transversely through
their respective fastener engaging portions 72 is an upstanding
resiliently deflectable arched portion 74 similar to element 28
illustrated in FIGS. 1 and 2. In this arrangement, however, the
axes of the slots 66 coincide with the centers of the respective
apertures 62 which are shown separated by a distance T5. When
employed in conjunction with a terminal block such as 52
illustrated in FIG. 3, the distance T5 is arranged to be either
slightly greater or slightly less than the distance T4 between the
terminal screws 48, 50. In this way, each pair of fastener
receiving portions 72 may be deflected either slightly inwardly or
slightly outwardly, depending upon the particular dimension of T5,
to cause the slots 66 to coincide with the respective shanks of the
terminal screws 48, 50, and the strip thereafter urged against such
terminal screws until their shanks are seated within the apertures
62 of the strip 60. The strip 60 will then tend to return to its
original undeflected state urging the side walls of the apertures
62 against the shanks of the respective terminal screws 48, 50 to
lock the strip in position thereat. The strip 60 may thus be
employed to interconnect three or more adjacent terminals to one
another in a manner similar to that set forth above with respect to
the embodiment illustrated in FIGS. 1 and 2. Since many terminal
blocks now in common use are generally constructed with relatively
standard center to center terminal spacings, the fabrication of a
strip such as 60 with suitably spaced apertures becomes a simple
matter of determination to provide the locking action described
hereinabove. The strip 60 may be further modified wherein given
sets of apertures 62 are spaced on centers equivalent to the
spacing T4 between terminal screws such as 48, 50, and other sets
of apertures 62 on the strip 60 are spaced on centers different
than the spacing T4 between the terminal screws 48, 50 where it may
be necessary or desirable to reduce the force required to assemble
the strip to the terminal block. It has been found that a variation
in the spacing between the fastener receiving apertures 62 and the
spacing between the terminal screws 48, 50 in the order of from ten
to twenty thousandths of an inch is generally sufficient to provide
the necessary locking action.
Referring now to FIGS. 8 and 9, the deflectable upstanding arched
portion 28 and 74 illustrated respectively in FIGS. 1 and 6 may be
modified to provide, for example, two spaced arched portions such
as 76, 78 illustrated in FIG. 8, or a relatively narrow arched
portion 80 spanning less than the full width of the jumper strip.
Additionally, although the arched portions described heretofore
have been shown as integral with the remainder of the jumper strip,
such portions may be fabricated independently of the remainder of
the jumper strip, and of different material where, for example,
greater resiliency is desired, and such arched portion fastened to
the fastener engaging portions by soldering, welding, brazing, or
the like, to provide the necessary integrity therebetween.
* * * * *