WO2010084343A2

WO2010084343A2 - Improvements in and relating to electrical connector housings

Info

Publication number: WO2010084343A2
Application number: PCT/GB2010/050072
Authority: WO
Inventors: Farrel Roy Brenner
Original assignee: Farrel Roy Brenner
Priority date: 2009-01-21
Filing date: 2010-01-19
Publication date: 2010-07-29
Also published as: GB2478894B; GB2478894A; GB201112703D0; WO2010084343A3

Abstract

A two-piece housing (1) typically for an electrical connector (11) of the type for joining a plurality of electric cables (9) end-on-end in which each housing piece (2, 3) includes a cable inlet region (5) having a cradle portion (6) for receiving a respective part of the cabling and, adjacent the cradle portion, a cable tie capture formation (7), such as a slot, for receiving the leading end (8a) only of a slotted cable tie (8) such that after adjacent cables have been connected together and the housing closed, the free end of each cable tie can be inserted into its respective capture formation, wrapped around its respective cable and then inserted into the slotted end of the cable tie, to thereafter be pulled tight to secure each respective cable to its respective cradle.

Description

Improvements in and relating to electrical connector housings

This invention relates to housings for electrical connectors particularly, but not exclusively, for electrical connectors used in and around buildings. The terms "electrical connector" and "electrical cable" as used herein are intended to include all kinds of cables and cable connectors including, without limitation, optical fibre cables.

It is well known that where one electrical cable has to be spliced or otherwise connected to another electrical cable, thereby exposing the electrical conductors, it is important to protect them from coming into contact with other electrical conductors nearby or with the housing itself, which must of necessity be electrically insulated and also sufficiently strong to withstand e.g. the physical shock of an object falling onto it and thereby breaking the housing or deforming it to the extent that short circuiting may occur and/or overheating of all or part of the electrical cable, whether at the point of the splice or elsewhere within the housing.

It is also well known that unmounted housings for electrical connectors must provide means preventing or inhibiting the cable from being pulled out, whether partially or wholly, and a conventional way of achieving this is to mechanically fix it in place by using a close fitting cradle forming part of the housing into which the cable is inserted before being retained thereon by means of a locking mechanism, such as a tab bridging the opening of the cradle forming part of the housing and being secured thereto by a pair of screws on respective sides thereof. The housing itself may take many forms, one such being described in US Patent 5502280, which describes a two-part threaded housing connected together after a pair of cables have been spliced or otherwise connected together by relative rotation of one part of the housing with respect to the other. However, a disadvantage with this arrangement is that it requires a number of rotations in order to close the housing which, in turn, can be difficult and time consuming within e.g. the confines of a building under construction. In addition, it will be apparent that the overall length of the housing in its open position is necessarily longer than in its closed position due to the presence of the co-axial screw threads and the consequent necessity to rotate each housing piece with respect to the other many times in order to open or close the housing, thereby making an inefficient use of materials from which it is made, more particularly given that the threaded region where the two halves meet are, for the full circumference of the thread, more than twice the thickness of the walls of the rest of the housing halves. In the manufacturing process female thread needs to either be cut in post moulding or the mould tool needs to be fitted with a rotationally extracting core. Both these processes slow down the manufacturing process and it is well known that both of these arrangements adds significantly to the cost.

In US 4684764 the foregoing problem has been addressed by the use of a bayonet type of fitting in which diametrically opposed pins extending from the open end of one half can be inserted within generally 'L-shaped' slots whereafter they can be rotated radially about the major axis of the housing and retained in that position by means of locking formations or recesses. This general arrangement is also shown in EP0171349, except that three such pins are disposed radially around the outer circumference of one half of the housing, thereby increasing the stability of the arrangement normal to the longitudinal axis of the housing. Although both of these embodiments teach ways of quickly connecting two halves of a two part housing for an electrical connector they each require that either the cable itself is sufficiently strong to withstand any pulling forces away from their point of connection or splice, such as where it is used for high voltage cables, or where the housing is to be used with more physically vulnerable electric cables, such as are commonly used within buildings, then as shown in EP0171349, Figure 7 thereof, some kind of anchoring arrangement has to be adopted which, by definition, must be of a size which reasonably matches the outer diameter of the cable so that mechanical force can be applied to it by means of e.g. a pair of clamping screws.

The present invention is derived from the realisation that there is a need for a two part housing for protecting electrical cables that have been axially spliced or otherwise joined together end-on-end that can be used for a relatively wide range of diameter cables, that is quick to connect together and yet which allows the cables to be mechanically secured to each housing piece quickly and substantially without the need for tools such as screwdrivers etc.

A two-piece housing for a plurality of cables to be connected end-on-end CHARACTERISED IN THAT each housing piece includes a cable inlet region having a cradle portion for receiving a respective part of cabling inserted through the cable inlet region, and adjacent the cradle portion a cable tie capture formation, such as a slot, for capturing the slotted end of a cable tie, the arrangement being such that the cable tie can then be wrapped around the cable in this region and the free end inserted into the slotted end of the cable tie, to thereafter be selectively pulled tight to secure the cable against the cradle portion.

This arrangement is particularly convenient when working in confined or awkward conditions, such as when working from a height, where the cables are to be aligned and connected vertically end-on-end, since after the uppermost one has been inserted through the inlet region of its respective housing piece by an amount sufficient to allow easy access to the cable end for the purposes of connecting it via an electrical connector to the other cable end the cable tie may be pulled tight only by an amount sufficient to stop the uppermost housing piece from sliding down the cable. Similarly, the lowermost housing piece can be temporarily secured in a position remote from the intended point of connection between the cables, allowing them to be connected in any suitable manner before the housing pieces are then joined together, whereafter both cable ties can then be fully tightened against their respective cradle portions.

The cradle portions are conveniently stepped, such as by being in the form of a recess, so that as the cable tie is fully tightened the cable becomes slightly kinked or deformed in this region, thereby preventing or inhibiting further movement of the cable along its major axis.

Conveniently, relative rotation between each housing piece allows the housing to be opened and closed.

Alternatively, each housing piece is connected via a push and click fit.

Advantageously, a guide is provided for each cable tie such that, after insertion of the leading end of the cable tie into the capture formation the cable tie is constrained to move towards its slotted end about a plane substantially normal to the major axis of the cable at the cradle portion.

The guide may be in the form of an open slot in the cable inlet region of the housing in line with the capture formation.

The housing may include an integral electrical connector for joining a plurality of cables or cable wiring.

The housing may include an elastomeric seal provided at the cable inlet region of each housing piece for preventing or inhibiting ingress of contaminants into the housing when closed. The seal may be in the form of a boot, which may be annular, to cover the cradle, cable and cable tie in this region of the housing.

The housing may further comprise a protective shroud or cowl, which may be annular, preventing or inhibiting ingress of contaminants where each housing part connects with the other.

Conveniently, the protective shroud or cowl is integral with one half of the housing and extends over part of the other housing piece.

According to a second aspect of the invention there is provided a method of connecting a plurality of cables end-on-end and enclosing the connection in a two-piece housing of the type described in the first aspect of the invention, including the steps of inserting each cable into its respective housing piece through the cable inlet region by a required amount, subsequently wrapping the free end of a captured cable tie around the cable and inserting it into the slotted end of the cable tie, thereafter pulling the cable tie tight by a required amount to at least temporarily hold the housing piece in position on that cable, thereafter making the required connection between the cables and, if necessary, sliding the housing pieces towards each other along their respective cables and connecting the housing pieces together, and thereafter pulling the cable ties fully tight to complete the connection of the housing to the joined cables.

The invention will now be described, by way of example only, with reference to the accompanying drawings in which:

Figure 1 is an exploded perspective view of a two-piece electrical connector housing in its open position and showing an electrical connector therein connecting two electric cables end-on-end,

Figure 2 is a view of the housing shown in Figure 1 in its closed and fully secured condition,

Figure 3 is a sectional side elevation of the closed housing shown in Figure 2,

Figures 4a and 4b are respective end elevations of the housing shown in Figure 2,

Figure 5 is a sectional view of the housing shown in Figure 2 in its open position, and

Figure 6 is a side elevation of the housing shown in Figure 2 in its closed position.

Referring firstly to Figure 1 there is shown an open/disassembled two- piece electrical connector housing shown generally at 1 comprising two generally cylindrical housing halves of which housing piece 2 is a male fit within the female housing piece 3, the latter of which includes a shroud or cowl 4 for preventing or inhibiting the ingress of contaminants such as dirt etc, when the housing pieces 2, 3 are joined together.

The housing pieces 2, 3 further include at their respectively opposite ends, when joined, cable inlet portions shown generally at 5 in the form of a bifurcated annulus having a lower cradle portion region 6 which includes a cable tie capture formation 7 in the form of a slot for receiving the leading end 8a only of a conventional slotted cable tie 8 (shown in Figure 2) of the type in which the tapered leading edge 8a is wrapped around an object to be secured, such as a cable 9, before being inserted into the correspondingly shaped slotted end 8b of the cable tie 8 whereafter the leading edge 8a is pulled and tightened against locking formations in the form of ridges along the cable tie and within its slotted end 8b. Hence, as can be seen more clearly with reference to Figure 2, parts of cable 9 to be axially joined end-on-end can easily be secured against the cradle portion 6 by simple insertion of the tapered free end 8a of the cable tie 8 into the cable tie capture formation 7 and the respective ends thereof connected together to secure the portion of cable 9 in place against the cradle portion 6. To facilitate correct alignment thereof, the cradle portion 6 includes a guide shown generally at 10 in the form of a bifurcated annulus between which the free end 8a of the cable tie 8 may be guided about the plane normal to the cable 9 in this region, over and around a portion of the cable 9 for the purpose of subsequently securing the cable 9 to the cradle portion 6 in the manner as aforesaid.

Referring again to Figure 1 , it will be seen that a pair of cables 9 are joined together end-on-end by means of a conventional screw-threaded connector block 1 1 , although it will be appreciated that other types of connectors or connections may be used including push fit connectors and conventional splicing of e.g. single power cables, connection of co-axial cables by means of co-axial connectors, and so on, whereafter the housing pieces 2, 3 may be closed together, rotated with respect to each other to engage locking formations therebetween to achieve the closed condition shown in Figure 2. Alternatively, the connection of both housing halves may be by a push and click arrangement of conventional type.

In Figures 3 to 6 there are shown sectional, end and side views of the two-piece housing according to this embodiment of the invention in which it will be seen that the male housing piece 2 includes generally 'L' section lip formations 12 arranged radially around the open periphery thereof which engage with correspondingly shaped latching members 13 on the open periphery of the female housing piece 3 so that when they are joined together and rotated clockwise with respect to each other the housing 1 is closed. At the junction between the housing halves 2, 3 the shroud or cowl 4, which may be integral or a separate element, prevents or inhibits ingress of contaminants in the joint therebetween such that, as more clearly shown in Figure 6, when closed the housing 1 is generally mechanically robust and is able to protect and hold whatever kind of cable connection is in the housing.

As can be seen more clearly with reference to Figures 3 and 5, the opposing upper edges 6a of each cradle portion 6 are stepped to define a shallow groove therebetween by which part of a cable (not shown) may be caused to become slightly kinked in a manner to be described.

In operation, cables 9 to be connected, spliced or otherwise joined together, whether individually or comprised of multiple wires or filaments, are threaded into respective inlet ends 5 of each of the housing pieces 2, 3 and are thereafter connected to each other in any suitable manner, such as by means of a standard electrical connector block 1 1 shown in Figure 1. Thereafter, the housing halves 2, 3 can be simply joined together by means of a twist and lock action, although it will be appreciated that any suitable connection means may be used, including a push and click means where resiliently deformable locking formations into correspondingly shaped slots allow simple and effective closure of the housing 1. In such condition, it will be appreciated that the cables 9 are still able to move axially within the housing 1 and in order to prevent or inhibit this it is a simple matter of threading the leading end 8a of a standard slotted cable tie into the slot 7, acting as a cable tie capture formation and to then wrap the cable tie 8 around the cable 9 with the aid of the guide slot 10 and to then reconnect the free end 8a of the cable tie to itself via its slotted end 8a in a conventional manner, whereafter it can simply be pulled tight to thereby secure the cable 9 to the cradle portion 6.

The presence of the raised steps (6a) in each cradle portion 6 means that as the cable 9 is secured in place via the cable tie 8 it becomes slightly kinked in this region, thereby increasing resistance to the cable being pulled away from the housing 1 , although it will be appreciated that other formations may be used instead, such as ridges which grip part of the cable 9 to thereby increase resistance to the cable being pulled from the housing 1. Hence, it will be appreciated that the housing 1 is able to secure in place quickly and easily cables of varying diameter and without the need for tools such as screwdrivers etc. As will also be appreciated, a potential disadvantage of this arrangement is the possibility of contaminants entering the inside of the housing 1 at the point of entry of cables 9, but this potential problem can be easily resolved by the use of adhesive tape or an elastomeric seal for covering the cradle portion, cable tie capture portion and cable in this region, which seal may conveniently be in the form of an elastomeric boot threaded onto the cable 9 before it is connected to another cable 9, whereafter on closure of the housing 1 the boot is slid over the various exposed parts to effectively seal the housing 1 from unwanted contaminants.

Although the invention has been described with reference to a substantially cylindrical housing for connecting cables that are to be joined end- on-end, it will be appreciated that other shapes of housing may be used. Similarly, the invention is not limited to the use of a housing for joining just two cables together but may include more cables, such as cables arranged to be joined together polygonally forming e.g. a three way, four way, or five way connection, for example.

The means by which the cable ties are secured in place are also not limited to use of a closed slot 7 and, for example, can include simply a recess preventing or inhibiting movement of the cable tie along its major axis and hence the cable to which it has been secured.

The cable tie itself may be formed integrally with each housing piece 2, 3, although in the preferred embodiment the housing pieces 2, 3 are adapted to be used with cable ties of varying sizes to suit cables of varying diameters, all of which can be connected together by any suitable means and thereafter retained against the housing 1 quickly, efficiently and without the need for time consuming tools such as screwdrivers to turn screws to, in turn, clamp variously sized cables to the housing 1 via clamping tabs or similar forms of adjustable locking arrangements.

The method of the invention may be varied to suit the circumstances and, for example, where a cable to be spliced or otherwise connected together is easily accessible and supported horizontally on e.g. cable ducting, the connection may be made and the housing pieces connected together before cable ties are then used to secure the respective parts of the cable to its respective cradle portion. Alternatively, as described above, the cable ties may be used to temporarily secure each housing piece on its respective cable at a point remote from the point of connection and thereafter slid along the cable to the required point of connection without risk of one or both of the housing pieces becoming detached, more particularly when the joined cable is to hang vertically.

The invention in its various embodiments therefore provides a quick and efficient way of connecting cables of varying sizes with few or no tools other than those that may be required to make the connection between the cables.

Claims

1. A two-piece housing (1 ) for a plurality of cables (9) to be connected end- on-end CHARACTERISED IN THAT each housing piece (2, 3) includes a cable inlet region (5) having a cradle portion (6) for receiving a respective part of cabling inserted through the cable inlet region, and adjacent the cradle portion a cable tie capture formation (7), such as a slot, for capturing the slotted end (8a) of a cable tie (8), the arrangement being such that the cable tie can then be wrapped around the cable in this region and the free end inserted into the slotted end of the cable tie, to thereafter be selectively pulled tight to secure the cable against the cradle portion.

2. A housing according to claim 1 FURTHER CHARACTERISED IN THAT the cradle portion of each housing piece includes formations (6a) to permit the cabling to be kinked in this region when the cable tie is pulled tight.

3. A housing according to claim 2 FURTHER CHARACTERISED IN THAT the formations are one or more steps (6a).

4. A housing according to any preceding claim wherein relative rotation between each housing piece allows the housing to be opened and closed.

5. A housing according to any one of claims 1 to 3 wherein each housing piece is connected via a push and click fit.

6. A housing according to any preceding claim wherein a guide (10) is provided for each cable tie such that, after insertion of the leading end of the cable tie into the capture formation the cable tie is constrained to move towards the slotted end about a plane substantially normal to the major axis of the cable at the cradle portion.

7. A housing according to claim 6 wherein the guide is in the form of a bifurcated annulus (10) having an open slot in the cable inlet region of the housing in line with the capture formation.

8. A housing according to any preceding claim including an integral electrical connector for joining a plurality of cables or cable wiring.

9. A housing according to any preceding claim wherein an elastomeric seal is provided at the cable inlet region of each housing piece for preventing or inhibiting ingress of contaminants into the housing when closed.

10. A housing according to claim 9 wherein the seal is in the form of a boot to cover the cradle, cable and cable tie in this region of the housing.

1 1. A housing according to claim 10 wherein the boot is annular.

12. A housing according to any preceding claim further comprising a protective shroud or cowl (4) preventing or inhibiting ingress of contaminants where each housing piece connects with the other.

13. A housing according to claim 12 wherein the shroud is annular.

14 A housing according to claim 12 or 13 wherein the protective shroud or coil is integral with one housing piece and extends over part of the other housing piece.

15. A two-piece housing for an electrical connector substantially as hereinbefore described with reference to the drawings.

16. A method of connecting a plurality of cables end-on-end and enclosing the connection in a two-piece housing of the type described in the first aspect of the invention, including the steps of inserting each cable into its respective housing piece through the cable inlet region by a required amount, subsequently wrapping the free end of a captured cable tie around the cable and inserting it into the slotted end of the cable tie, thereafter pulling the cable tie tight by a required amount to at least temporarily hold the housing piece in that position on that cable, thereafter making the required connection between the cables and, if necessary, sliding the housing pieces towards each other along their respective cables and connecting the housing pieces together, and thereafter pulling the cable ties fully tight to complete the connection of the housing to the joined cables.

17. A method of connecting a pair of cables within a two-piece housing substantially as hereinbefore described.