Note: Descriptions are shown in the official language in which they were submitted.
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l~LO~G~ LECl~RICAL CONN13CTOR lRETAI~G DE~VIC~
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This invention relates to devices for securing or retaining cable
connectors in their mated positions to prevent acci~ental disconnection and,
5 more particulRrly, it relates to devices for retaining elon~te cable connectors in
their mated positions.
Electrical cable connectors are well-known and widely used in
electronic systems to connect various subsystems together. ~uch elecl:rical
connectors are often elongate and formed such that a row or a plurality of rows
10 of contact elements arejoined when the male and female elements of an overallconnector are mated. In some connectors, electrical connection is made by male
pins mating with corresponding female apertures. In other connectors, an
elongate island in the male element supports a row or a pair of rows of side-by-side mounted ribbon-like contacts. The male ribbon contacts mate with
15 corresponding female ribbon contacts mounted side-by-side in an island receiving
aperture formed in the female element. Usually the ribbons or pins lie along
axes that are orthogonal to the longitudinal axis of the overall connector
elements. And, usually, the cables enter the connector elements at one end.
Prior art connectors formed in these and similar manners can make 50 or more
20 separate electrical conneetions when the male and ~emale elements are mate~
together. Such connectors are sold by Blmker Ramo Corporation of Oakbrook, IL
60521 under the trademark AMPHRNOL and by Amp, Inc. OI Harrisburg, PA
17105 under the trademark CHAMP. Other companies sell similar types of
electrical COMeCtorsO These elongate electrical cable connectors are sometimes
25 generically referred to as ribbon connectors. The invention was developed Ior use in conjunction with such connectors.
It is o~ten necessary to secure elongate electrical cable connectors
after the male and female elements are mated to prevent accidental
disconnection. Previously, one common~ method of securing connectors used
30 screws to clamp the flanges of the male and female elements together, or to
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clamp the elements to a circuit board or mounting panel receptacle. While this
technique secures the connection, it has a number of disadvantages, particularlywhen used in a situation in which the connector elements are to be disconnected
from time to time. Specifically, the fastening and unfastening of screws is a
5 time-consuming, tedious process and, therefore, undes;rable. Also, because of
the generally small size of the screws used, it is easy to both strip the threads of
the screws and lose screws. Even the use of a captive typc screw is not entirelyfoolproof. Further, because OI the space constraints in many locations, it is
difficult to obtain easy access to connector screws using a screwdriver or otherlO tool. The present invention is directed to providing an elongate electrical cable
connector retaining device that overcomes these disadvantages.
More specifically, it is an object of this invention to provide a
device for retaining elongate electrical cable connectors in their mated position
A further obiect of this invention is to provide elongate electrical
15 cable connector retaining devices which do not require screws and, which are
inexpensive to manufacture and easy to install.
A still further object of this invention is to provide electrical
connector retaining devices suitable for use with present forms of commercially
available elongate electrical cable connectors without modification to the
20 connectors.
Summary of the Invention
In accordance with this invention there is provided an integral strap
formed of a semi-rigid nonconducting material comprising: a planar region
having two opposing edges; at least two anehoring prongs integrally formed with
25 said planar region and extending outwardly from one of the two edges of said
planar region in the plane of said planar region; and, a ridged flange integrally
formed with said planar region and extending outwardly from the other edge of
said planar region.
In accordance with other aspects of this invention the ridged elange
30 includes several parallel ridges on one face that lie parallel to the edge of the
planar region from which the flange extends. When viewed in cross seetion the
ridges define right triangles. Preferably, the ridged flange lies in a plane oblique
to the planar region. Also, preferably, each anchoring prong has a bullet shapedouter end that is spaced from the related edge of the planar region such that a
35 notch is formed between the bullet-shaped end and the related edge of the planar
region. Further, preferably, each prong has a slot cut longitudinally down its
center whereby each prong is formed of two spaced halves.
Pre~erably, the integral strap is us~d with a rigid frame that may
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be integrally fo~med in a structure adapted to support a connector. For example,the rigid frame may be integrally formed in the backwall of a cabinet adapted tohouse an electronic subsystem; or the rigid frame may be formed in the chassis
of an electrical subassembly or device. Further, the rigid frame may be
integrally formed as part of a connector block. Alternatively, when the
connector is to be used to join two cables, rather than a cable to an electricalsubsystem, the rigid frame may be formed as a discrete item. Regardless of how
formed, the rigid frame includes an elongate aperture in whieh one OI the
elongate connector elements (e.g.9 either the female element or the male
10 element) is mounted. Formed in the rigid frame along one longitudinal side ofthe elongate aperture are holes adapted to receive the anchoring prongs. Formed
in the rigid frame on the longitudinal side of the connector aperture is a slot
adapted to receive the ridged flange of the strap. The rigid frame includes one
or more cross-bars adjacent to the slot or by a series of slots ormed in a wall15 adjacent to the flange receiving slot, depending upon the nature of the item
within which the rigid frame is integrally formed. When the rigid frame is a
discrete item, the cross-bars are preferably formed in a flange lying orthogonalto the plane within which the connector aperture is formed.
The semi-resilient strap is attached to the rigid frame by forcing
20 the anchoring prongs into the holes. As the prongs are forced into the holes, the
two halves of each prong move toward one another, i.e., the prong compresses.
When the bullet-shaped end has passed through the hole, and the notch is
reached, the prongs spring open and anchor the strap. In this manner, the strap is
affixed by the anchor prongs to the rigid frame. After a connector element is
25 mated to the connector element mounted in the aperture in the rigid frame, the
strap is wrapped or folded about the assembled connector and the ridged flange is
in~serted into the slot located on the opposing side of the assembled connector.When the strap is released the ridges engage the cross-bar or cross-bars, whereby
the strap is retained in its folded shape. This engagement oc~urs because the
30 semi-resilient strap attempts to return to its planar shape after being released,
whereby the ridges engage the cross-bar or cross-bars.
When it is desired to remove the strap, the sides of the folded strap
are pressed toward one another such that the ridges are disengaged from the
cross-bars. Then the strap flange is withdrawn from the flange receiving slot.
Preferably the strap is formed of a nonconductive material such as
virgin nylon or nylon with up to a 5% glass fiber filler. Also, preferably, an
alignment or positioning prong integrally formed with the planar region project
outwardly from the planar region, in the plane of the planar region and from the
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edge from which the anchoring prongs proje~t. The positioning prong is adapted
to enter R corresponding hole formed in the rigid frame adjacent the prong holes.
The positioning prong and its corresponding hole is positioned such that the
anchoring prongs must be inserted in their respective holes so that ridges face
away from the connector aperture.
It will be appreciated from the foregoing summary that the
invention provides a retaining or securing device suitable for use with elongateelectrical conductors that overcomes the disadvantages of prior art screw type
coupling mechanisms, discussed above Moreover, the retaining device of the
invention has additional advantages. For example, the retaining device of the
invention does not require the use of tools, such as screwdrivers. Since the strap
is anchored at one end, it will not be lost while it is in an open position.
Moreover, should the anchor posts break off, a strap can be readily and quickly
replaced. Also fastening and unfas~ening of the retaining strQp can be easily
performed using one hand. Thus, the invention is particularly suitable for use in
situations where the connector is to be mounted in a marginally accessible
location. Finally, because the strap is made of a nonelectrical material, it
cannot inadvertently cause electrical shorts should it come in contact with the
contacts of an electrical connector element.
Brief Description of the Drawin~
The foregoing objects and many OI the attendant advantages of this
invention wiU become more readily appreciated as the same becomes better
understood by reference to the following detailed description when taken in
conjunction with the accompanying drawings wherein:
FIGURE 1 is a perspective view of a semi-resilient strap formed in
accordance with the invention;
FIGURE 2 is a side elevational view of the strap illustrated ;n
FIGURE 1;
FIGURE 3 is a perspective view of a strap formed in accordance
with the invention in a nonretaining position anchored to a rigid frame forming a
portion of an electrical subsystem housing;
FIGURE 4 is a side elevational view, partially in cross section7 of
the retaining device illustrated in FIGUR~ 3, showing the strap in a retaining
position;
FIGURE S is a perspective view of a retaining device formed in
accordance with the invention suitable for securely connecting a pair of
connector elements neither of which is supported by a housing or other assembly;and,
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FIGURE 6 is a perspective view of the retaining device formed in
accordance with the invention in combination with a connector block including a
plurality of quick connector blades.
Description of the Preferred Embodiments
FIGURE 1 illustrates a preferred embodiment of a retaining strap
lO formed in accordance with the invention. The strap 10 is an integral element
formed of a suitable semi~rigid material, such as virgin nylon or nylon with up to
a 5% glass fiber filler, processed in ~he manner hereinafter described. The strap
includes a planar region L1, one or more anchoring prongs 12, a positioning prong
14 and a flange 16. The planar region is illustrated as rectangular and, thus, has
two opposing edges. The anchoring prongs 12 and the positioning prong 14
project outwardly from a common opposing edge of the planar region 11, in the
plane of the planar region 11. The ~lange 16 projects obliquely outwardly from
the other opposing edge of the planar region.
Each anchoring prong 12 has a bullet-shaped outer end 31 that is
spaced from the edge of the planar region from which the anchoring prongs
project. Thus, a notch 29 is formed between the bullet-shaped ends 31 and the
adjacent edge of the planar region 11. Each anchoring prong is formed of two
halves created by a slot cut longitudinally down the center of the anchoring
prong 12. The slots extend slightly into the planar region 11~ In addition, the
planar region is thicker or enlarged in the region where the planar region is
aligned with the anchoring prongs 12, for reinfor¢ement purposes.
Preferably, the flange 16 is narrower than the planar region 11. As
noted above9 the flange 16 projects oùtwardly from the plane of the planar region
11 at an oblique angle. Formed in the outer ~ace (e.g., the face defined by the
obtuse angle formed between the planar region 11 and the flange 16) are a
plurality of parallel ridges 18. The ridges 18 are elongate and lie along axes lying
parallel to the edge from which the flange 16 projects~ Preferably the ridges are
right triangular in ~ross section with a right angle facing the edge of the planar
region ll from which the flange 16 projects.
Preferably, the strap is injected molded of virgin colorless nylon or
nylon with up to a 5% glass fiber filler. After a strap i9 removed from a suitable
mold, while it is still hot, the ridged flange 16 is set at 30 and the strap iscooled. The strap is then boiled in water containing Rit dye for a mir,imum of
two hours. The purpose of boiling the strap in Rit dye is to foree the color into
the strap as well as anneal the nylon so that it is stronger.
In additiorl to the strap, a retaining device formed in accordance
with the invention aIso includes a rigid fr&me. The rigid frame may be an
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integral part of another structure or it may be separa~ely formed as a discrete
item. FIGURES 3 and 4 illustrate a rigid frame forming a portion of the wall of
the chassis or housing of an electronic subsystem. FIGURE 5 illustrates a rigid
frame formed as a discrete item. FIGUlRE 6 illustrates the rigid frame forming a5 portion of a ~onnector block including quick connector blades. Regardless of how
formed, i.e., integral or separate, the rigid frame includes common and discreteitems These items include: an aperture within which one element (e.g., male or
female) of an elongate electrical cable connector is mounted; holes located along
one longitudinal side of the aperture for receiving the anchoring prongs 12 and
10 the positioning prong 14; a slot located along the o?posing side of the aperture
for receiving the strap flange 16; and one or more cross-bars, located in a wallorthogonal to the plane in which the connector element is mounted, adapted to
interact with the ridges 18 of the strap flange 16.
FIGURES 3 and 4 illustrate the rigid frame formed as an integral
15 portion of the rear wall o a chassis or housing of an electronic subsystem. The
rear wall is depicted as a channel 2û. Thus~ the rear wall includes a pair of legs
41 and 43 and a cross-member 45. Formed in the cross-member 45 of the
channel 20 is an elongate aperture 17 suitable for receiving one element of a
connector (see FIGURE 4). The element, which may be a male or female
20 element, is attached to the channel by bolts, rivets or screws that pass through
apertures in ilanges that project outwardly from the connector and holes 35
located in the channel cross-member 45 on opposing ends of the elongate
aperture 17. Formed in the cross-member of the channel along one longitudinal
side of the elongate aperture 17 are three holes. The spacing between two of
25 these holes 13 is equal to the spacing between the anchoring prongs 12. The
diameter of the holes is slightly larger than the diameter of the anchoring prongs
in the region of the notches 29. The third hole 15 is spaced such that it will
receive the positioning prong 14 when the strap is positioned such that the ridges
18 face away from the elongate aperture 17. This orientation is accomplished by
30 simply locating the positioning prong 14 and its related hole nearer to one of the
anchoring prongs than to the other anchoring prong and its related hole.
The strap 10 is inserted by aligning the anchoring prongs and the
positioning prong with their related holes and pressing the prongs into their
related holes. Since the anchoring prongs are split, they are compressed when
35 they are pressed into their related holes. An adequate amount of pressure forces
the prongs to R point where the bullet-shaped ends 31 lie beyond the other ~inner)
surface of the cross-member 45 of the channel 20. When this point is reached,
the compressed prongs expand and anchor the strap, as best illustrated in
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FIGURE 4. Of course, the width of the notches 29 is generally equal to the
thickness of the cross-member 45.
Formed in the cross-member 45 of the channel 20 along the other
longitudinal side of the elongate aperture 17 is a strap slot 47 for receiving the
5 flange 16 of the strap 10. The slot is formed by removing the entire portion of
the cross-member from the elongate aperture 17 to the adjacent leg 41 of the
channel 20. Formed in the same leg 41 of the channel 20 are a plurality of cross-
bars 21 separated by slots 22. The strap slot 47, and the cross-bars 21 and slots
22, are equal in length to the width of the flange 16 of the strap 10. The leg
10 slots and the cross-bars form a ladder-like arrangement. The cross-bars are
spaced from one another by a distance adequate to allow a ridge 18 to enter the
slot formed by the spacing between a pair of adjacent cross-bars. Thus, when an
anchored strap is folded over such that the flange 16 can be inserted into the
strap slot 47, and then released, the ridges 18 will enter the slots between the15 cross-bars 21 and latc}l the strap in place. In this regard, it is pointed out that,
as discussed above, the strap is semi-resilient. ~s such the strap includes
springback that tends to press the ridges 18 into the slots 22 between the cross~
bars 21 after the strap is folded over, the flange is inserted into the strap slot 47
and then the strap is released. Since springback also tends to withdraw the strap
20 flange 16 from the strap slot 47, a constant pressure that keeps the ridges
engaging the cross-bars is created.
FIGURE 4 illustrates a connector mounted and restrained by the
restraining device of the invention. More specifieally, ~IGUIRE 4 illustrates anelongate cable connector element 27 mounted in the aperture 17. The elongate
25 cable connector element may be either the male or the female element of a
composite connector assembly. Mated to the thusly mounted connector element
27 is a detachable mating connector element 24. The strap 10 is illustrated as
folded over the backside of the mating connector element 24 such that the flange16 lies in the strap slot 47. One ridge 18 lies in a slot 22 formed between the two
30 illustrated cross-bars 21. Another ridge lies beneath the lower cross-bar.
Removal of the strap is a~hieved by pressing the folded (ridged)
side of the strap toward the connector, whereby the ridges 1~ are disengaged
from the slots 22, and withdrawing the flange from the strap slot 47. As a result
of the resiliency of the strap 10, after it is released, it will attempt to achieve
35 its original planar shape, illustrated in FIGIJRE 3. This planar shape will not be
fully achieved because the material will have received some "set" while it was in
the restraining position illustrated in FIGURE 4.
The inclusion of several ridges 18 allows the strap to be used on
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different size connectors and still tightly retain the connectors in their matedposition. This is achieved without the strap bending inwardly and losing contactwith the cross-bars, as might occur if the flange 16 were not made oblique to the
planar region 11. More specifically, if the flange 16 were co-planar with the
s planar region 11, the flange 16 would tend to curve inwardly after being folded
about an assembled connector, particularly when the ridges nearest the planar
region are needed to engage the cross-bars. This curve would have the additionaldisadvantage that it might impinge on wires connected to the supported
connector element 27. These undesirable effects are eliminated by the invention
10 as a result of the permanent oblique bend applied to the flange 16 during the formation of the strap 10.
It is pointed out here that because the flange 16 is narrower than
the planar region 11, only the flange 16 can enter the strap slot. The planar
region cannot enter the strap slot 47 because of its increased width. Thus, the
15 strap is prevented from entering the strap slot to an undesirable depth.
FIGURE 5 illustrates an embodiment of the invention adapted to
restrain a pair of connector elements neither of which are supported by other
items, such as a chassis or electronic subsystem housing. As a result, in this
embodiment the rigid frame 30 is formed as a discrete element. The discrete
20 rigid frame is an L-shaped plate, preferably formed of sheet metal. The elongate
aperture 17a within which one of the connector elements is to be mounted is
formed in one leg 25 of the plate. Located in the same leg along one side of theelongate aperture 17a (the side opposed to the other leg) are the holes 13a for
receiving the anchoring prongs of the strap 10. Located along the same side of
25 the elongate aperture is the positioning hole 15a. The other leg 23 of the rigid
frame 13 includes slots 21a forrrled between a series of cross-bars 22a. Tn order
to illustrate that the leg or flange within which the slots and cross-bars are
formed can extend transversely in either direction with respect to the plane
within which the elongate aperture is formed9 FIGURE 5 illustrates that the leg
30 23 extends toward the connector to be mated to the connector element mounted
in the elongate aperture~ as opposed to away from that connector. (In this
regard, it will be recognized that the leg of the channel within whieh the cross-
bars 21 were formed in the embodiment of the invention illustr~ted in FIGURES
3 and 4 projected away from the mating connector element 24.) Regardless OI
35 which direction the cross-bar leg points in, the cross bars and slots forrn aladder-like arrangement that latches the strap in place when the cross-bars
interact with the ridges of the flange of the strap 10 in the manner previously
described.
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FIGURE 6 illustra~es a connector block assembly including a
retaining device formed in accordance with the invention. The connector block
assembly includes a connector block 26, only a portion of which is shown in
FIGURE 6. The connector block 26 includes a plurality of quick connector
5 elements 28. Quick connector elements, as will be readily recognized by those
skiUed in the art, include a pair of wedge-shaped blades formed such that a wirecan be pressed between adjacent blades. When so pressed between adjacent
blades by a suitable instrument, the insulation surrounding the wire is cut by the
blades and the blades make contaet with the blades. Wires e2~end from the
10 blades 28, beneath the connector block 26, to a connector element 27a mountedin an aperture 17b formed in a flange 29 extending outwardly from the main
portion of the connector block 26. Screws or bolts 37 attach the flange of the
connector element 27a to the connector block flange 29. A strap 10, illustrated
as folded over in FIGURE 6, retains the connector elements together when a
15 mating connector element 24a is attached to the supported connector element
27a. The mating connector 24a is affixed to one end OI an electrical cable 39 ina conventional manner The strap 10 is formed in the manner illustrated in
FIGURES 1 and 2 and anchored to the llange 29 by pressing anchoring prongs into
holes (not viewable in FIGURE 6)~ located on one side of an elongate aperture
20 27d formed in the connector block flange 29. After being folded over the mated
connector elements 24a and 27aj the strap flange 16 passes through a strap slot
located along the other side of the elongate aperture 17b. A cross-bar 21 formedalong the outer edge of the strap slot interacts with one OI the teeth 18 to latch
the strap in its retaining position. The single cross-bar 21 is integrally formed in
25 the wall defining the outer edge of the connector block flange 29. As a result,
the rigid frame is integrally formed in the connector block flange 29. Obviously9
this same arrangement can be utilized with structures other than connector
blocks, if desired.
As will be readily appreciated by those skilled in the art and others,
30 many modifications and variations of the present invention are possible in light
of the above teachings. It is therefore to be understood that, within the scope of
the amended claims, the invention may be practiced ~herwise than as
specifically described herein.
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