~1.2~ 7 Backgroun_ Of The Invention_ The presen-t invention relates to a closure and more particularly to a closure Eor connec-ting telephone drop-wires.
Various connectors and closures are known in the art for connecting telephone drop-wires. Such closures and connectors generally include means for splicing conductors of the respective drop-wires. However, since often times the drop-wire is subjected to severe axial loads as can be caused by dimensional changes induced by temperature variations, high winds, heavy weight loads (e.g. ice), etc., the means for connecting and holding the drop-wires necessarily must be capable of accommodating these loads to prevent pull-out of one or both of the drop-wires from the closure or connector. Such electrical connectors and closures are generally complicated in design and expensive, and nevertheless do not guarantee a sufficient degree of reliability for withstand-ing axial pull-out.
In an effort to eliminate the above noted drawbacks and to provide a connec-tor for connecting wires which is relatively simple in design and inexpensive, various closures have been suggested in U.S.Patents 4,648,680 and 4,624,519.
While these closures are otherwise satisfactory, an improved closure is desired. Accordingly, it is an object of the invention to provide an improved closure which is simple in design and inexpensive to produce and which also provides improved axial strength.
rrhis and other objec-ts of -the invention will become apparent aEter reEerence to the following description considered in conjunction with the accompanying drawings.
BrieE Summar ~Of The Invention . _ . .
The objects of the invention have been achieved by a closure which is elegant in its simplicity. The closure comprises a casing having first and second fixed-sized passageways with each of the passageways having an insulation displacement connector disposed therein. The connector comprises a pair of spaced-apart walls each having at least one slot therein for receiving a wire wherein the slots in each pair of spaced-apart walls are laterally offset from one another. In a preferred embodiment -the closure further comprises a cover which is sized for mating with the casing.
As will become apparent hereafter the objects of the invention are achieved by use of the insulation displa-,~
cement connectors which provide the closure with high axial strength to resist pull-out. Additionally the insulation di~place~ent connectors pierce the wire insulation and provide electrical contact between the respective conductors so that a separate splice is not necessary.
Brief Descri~tion Of The Draw1ngs Figure l i5 a perspective view of the assembled closure.
Figure 2 i~ a top view of the casing with the cover of the closure rotated away from the casing in the direction of the arrow ~hown in Figure l.
Figure 3 i5 an enlarged view of the right half of Figure 2.
Figure 4 i9 a bottom view of the cover as viewed when the cover i9 rotated away from the closure as shown by the arrow in Figure 1.
Figure 5 i3 a view ~imilar to Figure 2 but with wires and a gel inserted therein.
Figure S i9 an enlarged partial sectional view in the direction of arrows VI-VI as shown in Figure 1.
Pigure 7 is a view similar to Figure 4 illustrating a ~econd embodiment of the cover.
E'igure 8 is an enlarged perspective view of a preferred embodiment of the insulation displacement connector.
Figure 9 is an enlarged perspective view of an alter-native embodiment 3f the insulation diqplacement connector.
Figure 10 is a view similar to Figure 6 showing meanson the cover for wedging the wires in the passageways.
Figure 11 is another view similar to Figure 6 showing alternative means on the cover for wedging the wires in the pa~sageways.
Figure 12 is a perspective view of a preferred embodi-ment of the assembled closure.
Detailed ~escription Of The Invention Referring to the figures in more detail and particularly referring to Figure 1 there is shown an assembled closure 10which generalLy comprises a casing 12 and a cover 14 which is ~ized for ma~ing with the casing. While it is most pre-ferred that the closure be used with the cover, it is not absolutely essential to certain aspects of the invention that the cover be u~ed with the casing. When the cover is rotated in the direction of the arrow 16 shown in Figure 1, the top of the casing is exposed as shown in Figure 2.
Referring now to Figure 2 there i5 disclosed according to the invention a closure 10 comprising a casing 12 including first 18 and second 20 fixed-sized passageways, each of the passageways having an insulation displacement connector 70 disposed therein. The connector comprises a pair of spaced-apart walls 72 each having at least one slot S 74 therein for receiving a wire. The slot.5, as will become more apparent hereafter, are laterally offset from one another. It is preferred that there be at least two insula-tion displacement connectors as shown in Figure 2. As stated just above, it is most preferred that the closure further comprise a cover which is sized for mating with the casing. As further shown in Figure 2, inlets 26, 28 for each of the passageway~ are on opposite side~ of the casing.
Referring now to Figure ~, there is shown in more detail the right half of Figure 2. As can be seen, each passageway has an in~ulation displacement connector 70. It is most preferred that the insulation displacement connectors in adjacent pa~sageways be connected in some manner so as to maintain electrical continuity between the connectors. The slot~ 74 of each connector are laterally offset from one another so that they are not longitudinally aligned. The slots will usually be offset from the middle of the passa~eway in opposite direc~ions. I a wire were to be placed within the insulation displacement connector, the wire would a~ume a configuration as schematically indicated by arrow 78. The offset slots of the insulation displacement connectors prevent the wire from straightening, thereby producing a high frictional force which r~sists axial pull-out of the wire. Additionally, the offset slots enhance electrical contact between the respective conduc-tor .5 .
It has been found that the insulation displacement connector 70 within each of the passageways provides high axial strength for wires inserted within the passageways so as to resist pull-out of the wires. Additionally, the insulation displacement connector 70 automatically pierces ,the wire insulation and preferably makes electrical contact between the respective electrical conductors of the wires.
T~us, stripping of the wires prior to insertion within the casing is unnecessary. All that need be done is insert the wires within the passageways of the casing and the wires be~ome wedged in place and simulaneously electrically con-nected.
Each of the passageways preferably has a plurality of fixed projections or teeth 22 therein. The projections or teeth shown in Figure 2 are viewed from the end but are actually longitudinally dimensioned as will become apparent hereafter. These projections or teeth provide additional axial strength for the closure to resist pull-out of the wires.
It i~ expected that the casing and cover will be made from themoplastic or thermoset molded parts.
Accordingly, it is expected that the fixed projections ! 25 or teeth will be molded in as well.
Referring now to Figure 4 there is shown the cover 14 which is sized for mating with the casing. The cover may simply have a flat surface so as to provide complete environmental protection of the wires inserted within the Eixed-sized passageways of -the casing. Alternatively, the cover may have an additional structure to be discussed in more detail shortly.
In Figure 5 there are shown wires 30, 32 inserted within each of the passageways of the casing. It can be seen that the wires are merely placed in position without their insulation heing stripped therefrom. In addition an electrically insulating gel 34 can be disposed in the casing so as to environmentally isolate the electrical wires and protect them from adverse environmental elements such as water. The gel can comprise a grease but most preferably it comprises a three-dimensional molecular structure having a cone penetration between 100 and 300 (10 lmm) and an ultimate elongatiQ;~ of at least 200%, such structures being formable out of urethane, silicon or a non-silicon liquid rubber. Such gels are described and claimed in U.S.
Patents 4,600,261, 4,634,207 and Canadian Patent application Serial No. 489,732 filed August 30, 1985. Hereinafter, reference to a "gel" is intended to be any of -the gels described in any of these patentsn Though the ~el is preferably used to fill the casing, it of course is apparent that this is not always necessary and the invention is usable in an unfilled state also. It is also preferred that the gel be included within the casing as shown in Figure 5.
As stated earlier the cover may have additional structure as shown in Figure 4. This structure consists of central spaced-apart projections 40 which define first 42 and second 44 fixed~sized passageways. Although not shown, the cover ~irqt and second passageways may also have fixed projections or teeth therein. Additionally the casing 12 as shown in s Figure 2 may have a central cavity 46 so that when the cover with the spaced-apart projections 40 i9 mated with the casing, the central spaced-apart projections 40 enter the central cavity 46 and the cover fir~t 42 and second 44 passageways register respectively with the casing first 18 and second 20 passageways. This additional structure has the advantage of providing additional support and environ-mental pro~ection for the electrical wires. The cover may further comprise insulation displacement connectors 48 disposed within each of the cover passageways. The insul~-tion displacement connectors 48 are substantial~y the sameas the insulation displacement connectors 70 discussed earlier. These insulation displacement connectors 48 serve to provide electrical contact between electrical wires inserted within the respective passageways.
In A second embodiment of the cover as illustrated in Figure 7, the cover 14 may also have fixed projections or teeth 50 on at least that portion 52 of the cover which overlies the passageways of the casing. The purpose of these projections or teeth is the same as the projections or teeth 22 in the casing, to wit, to provide additional axial strength for the closure to resist pull-out of the wires.
It is possible for the cover to have projections or teeth 50 as shown in Figure 7 and the casing to have ~2~
projections or teeth 22 as ihown in Figure 2. However, it is preferred that only the casing have projections or teeth as ~hown in Figure 2. These projections or teeth may be on one 54 or 56 but preferably both wall~ 54, 56 of the passageway~ as shown in Figure 2. Additionally or alternatively~ the passayeways of the casing may have the 'projections or teeth on the bottom 58 of the passageways.
If only the bottom 58 of the passageways contain the projections or te~th, then it i5 desirable that the cover have the projections or teeth.
Now, the closure may further comprise means for locking the cover and casing in firm engagement. These means may be as simple as screw~ which connect the cover to the casing.
However, screw~ are not preferred since in the working environment in which the closures are typically used it is undesirable to have small parts such as screws which can eaqily be misplaced. It is most desirable that the cover be designed so that it be snapped into place. In this regard locking means have been provided wherein the cover may be simply snapped into place over the casing. The operation of the locking means is illu~trated in Figure 6.
As can be seen, the cover has a latching portion 60 which snapc into an undercut 62 in the casing and is held there by ledge 64. Thi~ design resists the cover bein~
popped off a would ordinarily occur when the wires or cables are pulled upon. As also seen in Figure 6 there is qhown one of the passageways 20 with the longitudinally-dimensioned fixed projections or teeth 22 therein. For clarity the cover shown in Fiqure 6 is a flat cover wherein ~2~ '7 the additional structure as showrl in Figures 4 and 7 is missing. However, it i~ of cour~e contemplated within the scope of the invention that a cover may, and usually will, be used that haq this additional structure.
Shown in Figure 8 iq an enlarged perspective view of a most preferred embodiment of the insulation displacement connector 70. The connector comprise~ a pair of spaced-apart wall~ 72 joined by a connecting wall 80. When viewed in cro~s-~ection, the connector would appear U-shaped. Each spacad-apart wall has at least one slot 74 therein for receiving a wire. The slots are laterally offset so that when a wire i~ placed within the slot~, the wire would assume a configuration as schematically indica~ed by arrow 78. It is most preferred that adjacent insulation displace-ment conn~ctor~ 70 be connected by solid portion 76. Whenso connected, slots 74 are adjacent and connected to slots 741.
The mo3t preferred insulation di~placement connector is configured ~uch that wires may be placed upon adjacent slots 74, 74' and a~ the wires are pushed down, the teeth 82, 82' of the insulation displacement connector pierce and penetrate the wire in~ulation so as to make contact with the electrical conductors of the wires. Electrical contact bet-ween the respective electrical conductors is maintainedthrough solid portion 76 of the insulation displacement con-nector.
It is expected that the insulation displacement connec-tor shown in Figure 8 would be made ~rom a single piece of stamped steel, copper-clad steel, aluminum, beryllium copper or similar material. However, it is within the scope of the invention that the insulation displacement connector may be made in two or more pieces and then joined together during assembly of the closure. In those applications where it is essential to maintain electrical continuity between the wires, it would of course be most desirable for that electrical continuity to occur through solid portion 76.
However, it is al~o within the scope of the invention for electrical continuity to ~e maintained through a splice, in which case it i9 not essential for slot~ 74 and 74' to be electrically and/or phy~ic~lly connected.
Figure 9 illustrates an alternative embodiment 90 of the in ulation displacement connector. This em~odiment is especially suited for making butt connections between wires.
Thu~, all that need be done to form the connection is to place the wires end to end, as chematically illustrated by arrows ~2. Splicing of the wires is unnecessary since electrical continuity is maintained through wall 94.
Under certain circumstances, it may be desirable to provide a mean~ for assisting in the wedging of the wires in the passagewayR. Shown in Figure lO is such a means for wedging a wire within each of the passageways. The means consi3ts of a bo~q 96 on that portion of the cover ~hich overlies each of the passageways. As i9 apparent from Figure lO, boss 96 dips into each of the passageways. In use, once the wires are placed within the pas~ageways and the cover i9 placed over the casing, boss 96 wedges the ~2~ 3~
wires down lnto the passageways~ Bos.s 96 thus aids in the assembling of the wires and closure.
Figure 11 illustrates an alternative embodiment of the wedging meansO In this case, the wedging means consists of a sin~le boss 98 which overlies both of the passageways.
However, the function of bos~ 98 remains the same as boss 96 di~cussed above.
The preferred embodiment of the assembled closure is illustrated in Figure 120 In this preferred embodiment, the casing contains in~ulation displacement connectors 70, as illustrated for example in Figures 2 and 5, and the cover contains insulation displacement connectors 48~ a~
illustrated for ~xample in Figures 4 and 7. A particular advantage of the preferred embodiment is that the wires 30, 32 may be ~ituated vertically within the closure, instead of laying flat. Thus, bottom conductors 31, 35 may be electrically connected via connectors 70 and top conduc-tors 33, 37 may be electrically connected via connectors 48.
This arrangement makes for a very effective and compact closure.
It ~hould be understood that the closures according to the invention are suitable for connecting wires to wires, cable3 to cables or wires to cables. All the aforementioned applicationR of the closures according to the invention are thus contemplated to be within the scope of the invention.
The various embodiments de~cribed above are particularly Yuitable as aerial drop wire closures; however they alter-3~3~3'~
~1'1--natively may be used for buried drop wire connectors and enclosures. Additionally, the closures may have utility for telephone, CATV or power applications.
It will be apparent to those skilled in the art having regard to this disclosure that other modifications of this invention beyond those embodiments specifically described here may be made without departing from the spirit of the invention. Accordingly, such modifications are considered wi~hin the scope of the invention as limited solely by the appended claim~.