IE43535B1

IE43535B1 - A spliced electric cable moisture proof enclosure and a plug therefor

Info

Publication number: IE43535B1
Application number: IE1908/76A
Authority: IE
Original assignee: Preformed Line Products Co
Priority date: 1975-09-19
Filing date: 1976-08-26
Publication date: 1981-03-25
Also published as: AT358643B; IT1066541B; ZA765295B; AU1753976A; GB1503294A; IN145311B; DE2640600A1; DE2640600B2; CA1054234A; DE2640600C3; CH607396A5; FR2325223B1; FR2325223A1; BR7606159A; DE7628147U1; ATA653676A; JPS55857B2; MX144073A; IE43535L; JPS5239194A

Abstract

1503294 Cable splice conductors PREFORMED LINE PRODUCTS CO 16 Sept 1976 [19 Sept 1975] 38436/76 Heading H2E A plug for a cable splice enclosure comprises a body 10 having grooves 16, (17) along its length in which ends of cables 14 are received between which a splice 15 is formed, and slots (18), 19, (20), 21 extending across corresponding grooves, the depth of each slot being greater than that of its corresponding groove. The plug co-operates with a container 12 in which sealant 13 is retained, insertion of the plug and splice into the container causing sealant to be forced into the grooves and slots to provide a moistureproof seal. As shown, plug 10 is generally cylindrical and is retained on container 12 by arms 27, 28 in which are formed teeth 29 which co-operate with a thread 30 on the container. The grooves 16, 17 are of sufficient depth to enable sealant to be interposed between the cables and the container wall. Passages extend between slots (18), 19 and (20), 21 to assist in the penetration of sealant. More than two grooves may be provided. The sealant is preferably silicone, grease or petroleum jelly.

Description

This invention relates to a plug for fitting into the open mouth of a vial having a sealant therein to provide a moisture proof enclosure for a cable splice and its associated cable ends. The invention also relates to a moisture proof enclosure incorporating such a plug.

There are many instances where an electrical cable splice must be insulated and protected from the effects of the environment in which it is used. For example, in splicing a telephone service cable to the main cable, particularly in underground installations, protection must be afforded against the deleterious effects of moisture, not only on the electrical connection itself, but on the long lengths of the cable which the moisture may reach as a result of the effects of hydrostatic pressure and capillary action.

At present, a commonly used moisture proof cable splice enclosure for this purpose requires the placing of the splice in a suitable container filled with activated resin. After setting, the hardened resin, combined with the container, provides a certain amount of structural rigidity and prevents moisture from reaching the splice and the exposed ends of the cables.

Several disadvantages of this technique are apparent - 2 43535 and result primarily from the use of a sealing material which must be first activated and then cured to a hardened state. At the time of installation, the resin must be mixed with a catalytic compound and then the activated mix has to be poured into the container which is to enclose the cable splice where it is allowed to complete its chemical hardening process. The mixing and pouring of the resin involves separate containers and mixers, the end result of which is a general clean-up problem. The installer must also take great care when mixing the resin and when immersing the splice and cables so as to prevent the entrapment of air in the mixture which later could provide a cavity for the transmission of water or significantly weaken the structural strength of the resin. Lastly, the resin requires time to cure or harden. This curing time is mandatory because of the exothermic nature of the reaction which, if allowed to occur too quickly, may cause heat damage to the splice or the resin. During this curing time, the splice and cables must be maintained in a fixed position so as to prevent the creation of gaps caused by the relative motion of the embedded items with respect to the partially set resin.

The present invention provides a plug for closing the open end of a vial housing a cable splice and its associated cable ends, the plug comprising a body having grooves therethrough to receive the cable ends adjacent the splice, each groove being traversed by a slot whose depth is greater than that of the groove in the region where said slot intersects said groove, the plug also including clasping means operable to engage complementing coupling means on the vial and prevent axial separation of the plug therefrom.

Preferably, an additional slot traverses each groove, the slot or additional slot in one groove communicating with the respective slot or additional slot in another groove. »25 Conveniently, the slots are coplanar with each other and/or the additional slots are coplanar with each other, said slots and/or additional slots lying in planes normal to the longitudinal axis of the grooves.

In a preferred embodiment, two grooves are provided, the width of each groove being such that it snugly receives one of the cable ends.

The present invention further provides an enclosure for moisture proofing a cable splice and the cable ends associated therewith comprising an open ended vial containing sealant for receiving said cable splice and associated cable ends, a plug comprising a body having grooves therethrough to receive the cable ends adjacent the splice, each groove being traversed by a slot of a depth greater than that of the groove in the region where said slot intersects said groove, said plug being shaped to fit in and close said open end of the vial, the amount of sealant being suoh that when clasping means on the plug body are engaged with coupling means on the vial, the plug is forced into the sealant which deforms around the cable ends and the cable splice and completely fills and seals the grooves and associated slots in the plug. When the plug of the invention is used in conjunction with a vial filled with sealant, a moisture proof enclosure can be provided in a matter of seconds without any mixing procedure, curing time or mess.

The invention also precludes the possibility of the assembler improperly mixing or curing the seal. These advantages are obtained through the use of a vial which has been prefilled with a specific amount of sealant not miscible with water, and a plug according to the invention which rigidly holds the cables in place and closes the open end of the vial.

The cables, already spliced in a conventional manner, are positioned in the grooves with the splice and cable ends associated therewith projecting beyond one end of the plug.

The plug is then inserted into the vial with the splice, cable ends and part of the plug immersed in the sealant.

The sealant displaced by the splice, cable ends and a portion of the plug fills any voids between the plug, including the slots, the walls of the vial, and the cables, and provides a highly efficient seal precluding the intrusion of moisture. The slots allow the sealant to completely encircle the cable ends at a plurality of locations to ensure a continuous seal around the cable ends. Additional passageways may be provided to ensure the filling of the slots.

Once assembled, the waterproofed splice and cable ends are ready to be positioned in the ground or any other similar moist environments.

As can readily be seen, the present invention provides a quickly assembled, highly reliable, problem-free waterproof cable splice enclosure. Because the sealant can be prepacked in the vial and in its final form, there is no mixing, filling or curing problem. No extra equipment is necessary to assemble the enclosure and no time is wasted for the seal to cure or dry. Also, the number of operations required of the assembler is reduced which in turn reduces the probability of human error. Because the plug, rather than the sealant as in the case of a resin filled vial, supports all loads, there is less chance that a minor failure under load of the enclosure will cause the moisture proofing material to fail in its function. In addition, the splice can be removed if that should prove desirable. Since the sealant is of an inert nature, any leakage of the sealant from the enclosure is not likely to cause damage to the surroundings. 43335 A preferred embodiment of the invention will now be described, by way of example only, with reference to the accompanying drawings, in whichsFigure 1 is an exploded perspective view of a moisture proof cable splice enclosure incorporating a plug of the present invention with two cables spliced together; Figure 2 is an assembled view, partly in section of the cable splice enclosure of Figure 1; Figure 3 is a front elevation of the plug of the present invention; and, Figure 4 is a cross-sectional elevation taken along the line 4-4 of Figure 3.

Referring to the drawings, there is shown a plug 10 constructed to cooperate with a vial 12 to protect a pair of cables 14 spliced together by a conventional means 15. The vial is partially filled with a sealant 13 which is preferably a silicone grease or petroleum jelly but may be any other suitable substance not miscible with water, and which does not set but rather stays flowable for the normal life of the splice.

The plug 10 is generally cylindrical in shape and includes two or more longitudinal grooves 16 and 17 extending the length of the plug 10. These longitudinal grooves 16 and 17 are appropriately sized to permit receipt of standard cables 14. At the same time, it is preferable that the cables 14 fit snugly into the grooves 16 and 17 such that the cables will not be easily extracted from the grooves when positioned in the assembled enclosure. It is also of benefit that the grooves 16 and 17 be sufficiently deep to allow the cables 14 to sit inwardly from the outer cylindrical surface of the plug 10. This ensures that the cables will be displaced inwardly from the vial 12 so that sealant 13 may be interposed between the vial 12 and the cables 14 when in 3 3 3S the assembled enclosure. However, a large displacement of the cables 14 inwardly from the outer surface of the plug 10 is not suggested in that a large, direct sealant passage through the enclosure is not advantageous. It has been found that a U-shaped groove having a semi-circular bottom and having a total depth approximately 1/16 inch (.16 cm) greater than the width of the grooves is satisfactory. In this way, the cables 14 can be forced into the grooves 16 and 17 where they are tightly held and where a small sealant passageway exists such that the outside of the cables will be covered by sealant when the enclosure is assembled.

The grooves 16 and 17 are traversed by slots 18, 19, and 21 defined in the body of the plug 10, the depth of each slot being greater than that of the groove it intersects in the region where it intersects said groove, as can best be seen in Figure 4. The depth of the slots 18-21 allows sealant 13 to flow inwardly about the cables 14 to form complete rings of sealant around the cables 14 at each slot 18-21. Thus, a plurality of individual sealant areas are formed to ensure the complete seal of the cables 14.

A flange 22 extends outwardly about the upper portion of the body of the plug 10. This flange comes to rest on the upper edge of the vial 12 when the plug is fully inserted into the vial. In this way, a physical barrier is provided to close off even the narrow space between the plug 10 and the vial 12. The plug 10 extends from the flange 22 downwardly a sufficient distance to bring about displacement of the body of sealant 13 upwardly about the sides of the plug 10, through the grooves 16 and 17 and into the slots 18-21. Slots 18 and 19 and slots 20 and 21 communicate with one another through passageways 23 and 24 to further enhance flow of the sealant upwardly about the plug 10 as the plug 10 is forced into the vial 12.

To facilitate placement of the plug 10 in the vial 12 and ensure retention of the plug 10 in the vial 12, clasping means in the form of two arms 25 and 26 extend outwardly from the upper portion of the plug 10. Each arm 25 and 26 has an end portion 27 and 28 with inwardly disposed teeth 29 which may be caused to grip coupling means or threads 30 on the vial. The threads 30 allow mechanical placement of the plug 10 through the simple twisting of the vial 12. With the plug fully inserted into the vial 12, assembly of the enclosure is complete. By engulfing the splice, and filling all of the gaps around the plug, the sealant provides an effective waterproof seal. As soon as the plug has been positioned in the vial, the entire closure is ready to be placed in the ground or other similar moist environment.

Thus, a convenient and inexpensive moisture-proof cable splice enclosure is formed which is supplied in kit form where it may be used to quickly and conveniently form moisture proof enclosures about a variety of cable splices.

Claims

1. A plug for closing the open end of a vial housing a cable splice and its associated cable ends, the plug comprising a body having grooves therethrough to receive the 5 cable ends adjacent the splice, each groove being traversed by a slot whose depth is greater than that of the groove in the region where said slot intersects said groove, the plug also including clasping means operable to engage complementary coupling means on the vial and prevent axial 10 separation of the plug therefrom,

2. A plug as claimed in claim 1 wherein an additional slot traverses each groove.

3. A plug as claimed in claim 1 or claim 2 wherein the slot or additional slot in one groove communicates with the 15 respective slot or additional slot in another groove.

4. A plug as claimed in claim 2 or claim 3 wherein the slots are coplanar with each other and/or the additional slots are coplanar with each other, said slots and/or additional slots lying in planes normal to the longitudinal 2 θ axis of the grooves.

5. A plug as claimed in any preceding claim wherein the depth of each groove is greater than its width.

6. A plug as claimed in any preceding claim wherein the width of each groove is such that it snugly receives one 25 of said cable ends.

7. A plug as claimed in any preceding claim wherein the plug is cylindrical.

8. A plug substantially as herein described with reference to the accompanying drawings.

9. A moisture proof enclosure for a cable splice and its associated cable ends comprising a vial having a water insoluble sealant therein, the vial having a mouth at one end thereof sealingly closed by a plug as claimed in any of claims 1 to 8.

10. An enclosure as claimed in claim 9 wherein the vial is provided with threads around the mouth thereof for co-operation with the clasping means to draw the plug into the vial upon rotation of the vial relative to the plug.

11. An enclosure substantially as herein described with reference to the accompanying drawings.

12. An enclosure for moisture proofing a cable splice and the cable ends associated therewith comprising an open ended vial containing sealant for receiving said cable splice and associated cable ends, a plug comprising a body having grooves therethrough to receive the cable ends adjacent the splice, each groove being traversed by a slot of a depth greater than that of the groove in the region where said slot intersects said groove, said plug being shaped to fit in and close said open end of the vial, the amount of sealant being such that when clasping means on the plug body are engaged with coupling means on the vial, the plug is forced into the sealant which deforms around the cable ends and the 10 •ί 2 τ; π »/ 4 ώ Jog cable splice and completely fills and seals the grooves and associated slots in the plug.