GB2248148A - Method of manufacture of an electrical connector - Google Patents

Abstract

A branching connector on a cable is formed by cutting an outer sleeving in the cable (10) and arranging inner core cables on a support (fig 10c), then contacting core conductors of a spiked electrical device (15) such that spiked contacts (81, 82 and 83) puncture sleeves of the inner core cables and make electrical contact therewith. The support (11) may be formed around the spiked contact (15) and bonded to it. The support (fig 10c) may form a housing. A moulding may surround the spiked device (15) and support and bond to it. The spiked device (15) includes a rigid earth contact (14) and two sprung contacts (16). A counterpart (12) may connect the connector to a pendant fluorescent lamp. The lamp is intended for illuminating building work. <IMAGE>

Description

METHOD OF MANUFACTURE OF AN ELECTRICAL APPARATUS This invention relates to an electrical apparatus and more specifically but not exclusively, it relates to a method of manufacture of an adaptor with a cable for use, in one embodiment, with electrical lighting equipment.

It is well known that fluorescent tubes are preferable to conventional filament bulbs. One reason why fluorescent tubes are preferred is because they do not cast shadows. However, fluorescent lighting requires an earth connection.

A problem in the past, for example on building sites or inside closed rooms and passageways within buildings, where work has been carried out, has been that areas have required lighting because the ambient light levels were too low. As soon as work had been carried out, it was sometimes necessary to remove the temporary lighting and re-install it in a different part of the site or building. If this was not done the result was that large parts of the construction site or building were illuminated unnecessarily. Alternatively one or more electricians were employed to ensure that adequate lighting was available in the correct vicinity as and when work was to be carried out.In the former case excessive use of lighting was uneconomic, and in the latter case, because power points were not always available in the most convenient places, excessive extension leads were used, and often makeshift connections were made to the nearest available main cable, so as to provide a temporary power source for other branch cables. Clearly such practices were not only inefficient but in the latter cases were sometimes dangerous. This was especially the case where so called festoon lighting was used, that is several lights in parallel sharing a common source.

A problem with festoon lighting arrays was that they were difficult to connect together because the fluorescent tubes required significant electrical equipment such as starters, ballast and fuses so as to ensure that they received the correct level of power supply. Also, because of the necessity to connect the fluorescent tubes in parallel to one another, complicated electrical paths were required from one electrical junction box to the next. The connections between adjacent junction boxes were complicated so as to permit an electrician to use one, some or all of the possible junction boxes available to him. Another problem was that the festoon connections and junction boxes were bulky and considerable effort was required to erect them. Sometimes this entailed two or three electricians working together.The paradoxical situation arose that temporary lighting was sometimes required to erect the temporary lighting.

Festoon cables are cables which support a plurality of connectors. These cables have been manufactured either by cutting a long length of cable and forming connections with individual cable connectors, or by joining sections of cable with connectors in the form of a chain. In the former case the connections were liable to come away from the cable, whereas the latter technique was time consuming and the integrity of the cable depended on each connection, as the cable in effect comprised a plurality of links. Its mechanical strength and electrical integrity depending on the weakest link.

According to a first aspect of the present invention there is provided a method of manufacturing an adaptor integral with a cable comprising the steps of: forming a discontinuity in an outer-sleeving of a multi-core cable, so as to reveal inner cores, arranging at least one inner core in a predetermined position on a core support, engaging contact means with a conductive portion of each inner core, the contact being supported by a contact housing; and bonding the housing to the core support to form the adaptor.

Preferably all the cores are arranged on a core support.

A method of manufacturing a housing integral with a cable comprising the steps of: forming a discontinuity in an outer sleeving of a multi-core cable, so as to reveal inner cores, arranging individual inner cores in a predetermined position on a core support, engaging contact means with a conductive portion of each inner core, the contact means being supported by a contact housing; and bonding the contact housing to the core support to form the housing.

In one embodiment the discontinuity is formed in the sleeving of a three core cable by making first and second transverse cuts and removing a section of the sleeving so as to reveal the three inner cores. The inner cores are separated and positioned into a core support. Electrical contacts, in the form of metal spiked members, and supported in a contact housing, are urged into contact with the conductive portion of the three core cables by piercing their respective outer sleevings.

Preferably a guide is provided on the core to support the contact housing. The housing is shaped so that it is received in only one orientation by the guide on the core support so that it pierces the three core cable. The live, netural and earth cables then contact the correct respective live, neutral and earth contacts.

Preferably bonding is achieved by injection moulding a plastics material around the contact housing and core support. The adaptor which is integrally formed on the cable is preferably in the form of a housing and is shaped to receive an adptor insert. For example an adaptor insert may be connected to a fluorescent light.

In an alternative embodiment, which is preferably in the form of an adaptor for insertion into the aforementioned holder, the core support comprises a member having an aperture, through which aperture a multi-core cable passes, the support having an end surface, in which a plurality of core receiving grooves are provided.

Recesses may be defined in the grooves. These are for receiving spikes of electrical contacts. The spikes are supported in a housing and they are arranged to pierce insulating sleeving of individual cores. Means may be provided on the support for guiding the housing into place so that each contact is orientated to contact the correct inner core of the cable. Alternatively the guide means may be provided on the housing.

The adaptor may be used in conjunction with a three core cable, in which case three electrical contacts are provided within the adaptor; three spikes in the housing; and three grooves in the support.

Preferably the holder comprises three separate electrical contacts. One contact of which is supported on a solid support and the other two are supported on sprung supports. The advantage of such an arrangement is that, despite having the appearance of a standard bayonet connector, it is impossible to insert a standard bayonet fitting light bulb into the adaptor and to light it . As a result of this only specific equipment may be used and there is no danger of people inserting anything apart from that specific equipment into a redundant adaptor.

Preferably the three electrical contacts are arranged at 120 degrees to one another.

Preferably the holder is shaped to receive an insert, which may be an adaptor connected to a fluorescent tube. The insert may be a weatherproof cap, which seals those holders which are not in use.

Alternatively the insert may be another adaptor of a different connector.

Contacts of the other adaptor or insert are arranged such that those electrical contacts in contact with the solid contacts are sprung contacts; and those electrical contacts in contact with sprung contacts are solid. Such an arrangement of contact pairs, each having a sprung and a solid contact, ensure that only adaptors of the correct type may be used in conjunction with one another. In practice this means that only the specific type adaptors may be used to connect fluorescent tubes to the electrical cable. This ensures that stringent safety standards are maintainable whilst enabling a network of fluorescent lamps to be easily erected, as and where required, not necessarily by a skilled electrician.

When it is required to move the fluorescent lamps to a different vicinity of a building site, the fluorescent tubes and their back-up equipment are simply unplugged from the adaptor holders and carried to where they are needed. Such an arrangement is efficient both from the point of view of the amount of cable used and from the point of view of utilisation of electricians' time.

An electrical connector may comprise an elongate electrical conductor having a first adaptor disposed at an end thereof and a plurality of second adaptors disposed in parallel along its length.

Preferably the adaptors disposed along the length of the electrical conductor are each capable of receiving a light source. The light source may be a fluorescent tube.

As a result of this temporary lighting, in the form of self contained boxes with a fluorescent tube and requisite electrical back-up and supply equipment, can be easily connected to the electrical connector.

One advantage of the present invention is that light from a fluorescent tube previously connected can serve to illuminate or partially illuminate an area "ahead" of itself so as a subsequent fluorescent tube may be connected, whilst the current is switched on.

Coding lugs may be provided which act to prevent the accidental insertion of the wrong types of electrical equipment into an adaptor. These lugs may be bayonet like projections arranged to fit into slots or grooves.

The adaptor disposed at the end of one electrical conductor is preferably a standard plug but it may be of the type connectable to an adaptor disposed along the length of a second electrical conductor. This may be achieved by arranging for electrical adaptors, disposed at one or both ends of the electrical conductors, to be of a male type fitting and electrical adaptors, disposed along the length of electrical conductors, to be of a female type fitting. Of course adaptors disposed at the ends of electrical conductors may be female and those along the length of a conductor may be male.

In a preferred embodiment the adaptor has three, lugs disposed around its periphery. These lugs are disposed in such a manner so as to ensure the connection of an adaptor and holder may only be made in one orientation. This is achieved by disposing bayonets and receptors around the periphery of adaptors and holders in a non symmetrical arrangement.

It may be possible that by accident, or perhaps in the dark, an electrician attempts to insert a male adaptor into a conventional bayonet holder. Because of the combination of sprung and unsprung electrical contacts full insertion would not be possible. However, in one orientation, in an embodiment with two bayonet lugs, the two contacts of the adaptor could momentarily touch the live and earth contacts in the holder with the possibility of miscontact. This could result in a "short". By using three lugs, it is impossible to even partially insert a standard dual bayonet lamp into a three phase and/or higher power adaptor. Thus the third "coding" bayonet guarantees against the partial accidental insertion of a dual contact lamp into a live supply.Although a standard two pin bayonet lamp cannot be inserted into the holder, it could momentarily contact a live and earth contact and cause a short. The adaptor is otherwise identical to that described above.

Coding lugs may be dimensioned and/or arranged such that different lugs may be used on different equipment.

For example, a thick coding lug could be used on low voltage (llOV) equipment and a thinner lug on high voltage (240V) equipment. Such an arrangement would permit the insertion of high voltage hardware into a low voltage supply and prevent insertion of low voltage hardware into a high voltage supply. This system therefore further enhances the safety of the adaptor/connector arrangement.

Embodiments of the present invention will now be described by way of example only, and with reference to the figures in which: Figure 1 is a diagrammatical representation of an electrical connector showing first and second type adaptors with a fluorescent tube connected to the connector; Figure 2a is a section showing the mating together of first and second adaptors; Figure 2b is an underplan view of Figure 2a; Figure 3 is a side elevational view of the first adaptor; Figure 4 is an end view of the adaptor of Figure 3; Figure 5 is an end view of a second adaptor; Figure 6 is a side elevational view of the adaptor of Figure 5; Figure 7A is an underplan view of an adaptor insert; Figure 7B is a side elevational view of an adaptor insert; Figure 7C is an above plan view of the adaptor insert of Figure 7A;; Figure 8A is a slide elevational view of an adaptor with an additional coding lug; Figure 8B is an end view of the adaptor of Figure 8A; Figure 9A is an end view of the adaptor holder; Figure 9B is an end view showing bayonet lugs; Figure 10A shows an underplan view of a cable support; Figure 10B shows a side elevation of a cable support; Figure 10C shows an above plan view of a cable support; and Figure 11 is a detailed view of part of Figure 10C.

Referring to Figure 1, an electrical cable 10 comprises a three core insulated wire. Along the length of the cable 10 there is disposed six adaptors 11 (shown in detail in Figures 3 and 4). Each adaptor 11 has a solid earth contact 14 and two sprung electrical contacts 16 and 17. Connected to a second type of adaptor 12 is a fluorescent tube 24 and support box 25 which contains the necessary electrical equipment such as starters, fuses and ballast (not shown).

At either end of the electrical cable 10 there may be disposed this second type of adaptor 12. However, a conventional plug may be used.

The second type of adaptor 12 (as shown in Figures.

5 and 6) has two solid electrical contacts 22 and 23 and a sprung earth contact 21. Respective solid and sprung contacts are arranged in so-called mirrored pairs, so that each pair of touching electrical contacts comprises one sprung and one unsprung contact. This arrangement enables only electrical equipment of the same type, having the same dimensions and same spatial arrangement of contacts to be used in conjunction with each other.

Thus for example several connectors having these types of adaptors may be linked together in a so-called network.

Figures 2a and 2b show the mating together of the first adaptor 11 and second adaptor 12. Figure 2a shows in detail how the "mirrored" pairs of reciprocating contacts mutually engage with one another so that only electrical equipment having the same spatial arrangement of electrical contacts may be used in conjunction with the connector 10 or with like equipment. A sheathing 14A which surrounds the electrical earth 14 permits the two adaptors to counter-rotate with respect to one another relatively easily. This is because the end of the sheathing 14A lies flush with the electrical contact 14 and engages the sprung contact 21 on insertion of the bayonet into the connector. The sprung contact is thus depressed on insertion and remains so during the twisting action of connecting. Adaptor 11 has a housing 13.The housing 13 is formed from a plastics material by an injection moulding process.

Adaptor 12 is also formed from a plastics material and may be connected to a fluorescent tube, to a weather-proof cap or it may be part of another electrical connector 20. In the latter case the connection together of one electrical connector to another, enables a tailor made network of connectors to be produced. Such a network greatly facilitates lighting in dark corridors of buildings under construction or refurbishment. The connectors 10 are re-usable once the network has been dismantled. Also they enable more efficient use of cable as one electrical connector 10 may be joined to another instead of all connectors having to lead back to a common power source and connecting them to this in a hap-hazard manner as was previously the case.

Figures 3 and 4 show adaptor 11 with housing 13 removed. A solid electrical earth contact 14 is mounted on a plastics base 15. The plastics base 15 may be injection moulded. Sprung electrical contacts 16 and 17 are also mounted on the base 15. The earth contact 14 is solid and longer than the two other contacts 16 and 17. As a result of this it is impossible to introduce a conventional bayonet filament lamp (not shown) into either adaptor 11 or 12.

A separator 18, which may also be of a plastics material, is disposed between the three contacts which are themselves disposed at 120 from one another. The separator 18 not only gives strength to the adaptor but also isolates the contacts from one another thereby minimising the risk of a short circuit. Contacts 16 and 17 carry live two phase current.

Figures 5 and 6 show the second adaptor 12 in detail. In Figure 5 the adaptor 11, has a plastics base 19. Two bayonet connectors 20A and 20B are also shown.

A single sprung electrical earth contact 21 and two solid contacts 22 and 23 are again disposed at 120 to one another. The spatial arrangement of the contacts 21, 22 and 23 and the bayonet connectors 20A and 20B are such that the adaptors may only be used in one orientation. This ensures that the correct phase contacts and earth contacts of one adaptor 11 contact those of the other adaptor 12. This is very important when considering that it may be necessary to assemble networks of connectors together in poor visibility or even in pitch darkness.

Because the sprung contacts are flush with their plastic housing, the electrical contact which they touch keeps the spring depressed whilst the two adaptors engage. This is possible because of the manufacturing process of the adaptors. The steps of manufacture involve firstly pressing brass electrical contacts into the injection moulded plastics housing, urging spiked portions of the contacts through outer sleevings, so as to contact respective electrical cables and finally encapsulating the adaptor in a plastics cover for strength and to insulate it. This is done by injection moulding the synthetic plastics around the core support.

Similarly the manufacturing of the second type of adaptor involves pressing brass contacts into an injection moulded insert so as to contact the wires.

This pressing of earth contacts ensures that they remain flush with the plastics insulating surround.

The adaptors described when used in conjunction with electrical equipment permit quick and simple erection of lighting and/or power facilities for example on working sites or at the scene of a disaster or emergency; they provide a network for safe power transmission which is custom made for the chosen site and ensure efficient utilisation of electricians' time.

Although it is impossible to fully insert a standard two bayonet lamp into the twin bayonet adaptor of the aforementioned embodiment, because of the unsprung earth contact and plastics surround it may be conceivable that by accident, or perhaps in the dark, an electrician could attempt to insert an adaptor into a conventional twin bayonet holder. Because of the combination of sprung and unsprung electrically contacts, full insertion would not be possible. However, in one orientation the two contacts of the lamp could momentarily touch the live and earth contacts in the second type of adaptor, the so-called holder. This would result in a "short", as described above.

Figures 8A, 8B, 9A and 9B show how the adaptor 12 and holder 11 have been modified so as to permit the insertion of only the correct equipment even by accident, by the addition of coding lugs 100A, 100B and 100C. Because of their orientation they prevent the aforementioned accident from occurring. This is achieved by adding an extra lug onto the adaptor. The lugs 100 are shown orientated in a trefoil fashion, with two lying at 1800 to one another and the third interposed at 900 to both of them. The disposition of the lugs ensures that the adaptor and holder may only engage (even partially) in one orientation.

Bayonet receptors 102 are similarly oriented so as to receive, the lugs 100. The addition of the extra coding lug 100B is only really necessary with equipment which will be live and into which components may be inserted. Respective receptors 102 A,B and C, receive repective lugs 100 A,B and C.

Figures 7A and 7B show an adaptor insert 103.

The insert. 103 is arranged and shaped to receive sheathed wires. The wires, are urged into the insert at the assembly stage. The insert serves to hold the three wires at the correct orientation to one another i.e. at 1200, during the fabrication process. One or more slots 104 or location tags on the insert, mate with a raised groove or sympathetic depression in the plastics base 15.

These slots 104 serve to locate the insert 103. The wires (not shown) are therefore held in place during manufacture and do not kink, twist or move away from their respective electrical contacts during the bonding stage when the adaptor or holder is made.

The same reference numerals have been used for figures 7, 8 and 9 as have for the other figures 1-6.

Figures 10A, 10B and 10C show different views of a cable support 50. The support 50 formed from a synthetic plastics material comprises a body having four legs 51A, 51B, 51C and 51D and a generally round body portion 52. The body portion 52 is slightly raised from the part of the support on which the cross pieces 51 are mounted. At the end of each cross piece 51 is a leg 53A, 53B, 53C and 53D. Each leg is supported on the cross piece bearing its initial letter respectively. At the end of each leg 53 there is a slight indentation.

On the under side of the support 50 there are three pairs of cable locating pins 55L, 55N and 55E. Each pair of pins receives one of the cables in the three core cable namely one of cables: live neutral or earth.

Between the pins there is an indentation which is preferably a hole moulded in the body 50 at the fabrication stage. This is shown in detail in the part figure. The hole receives a spike which is integral with a sprung or unsprung brass electric contact.

The method of manufacture of the housing 11 will now be briefly described with reference to the aforementioned Figures. A cable 10 is cut and a portion removed. The cable 10 is placed in a cable support 50 with respective live, neutral and earth cables lying in the correct channels of the cable locators 55. Letters may be imprinted on the body 50 adjacent each cable locating means, so as to assist the assembler. The base portion 15 then receives three electrical brass contacts 14, 16 and 17. All the electrical contacts have a spiked end 81, 82 and 83. Electrical contacts 16 and 17 are sprung electrical contact is unsprung and is shrouded by a plastics surround 14A.

The assembled adaptor housing is then pressed against the cable support 50 such that each of the spikes pierces the sheathing of each cable (not shown) making electrical contact therewith. Channel 84 in the base 15 rests around the cable 10 and the legs 53 enable the exterior housing 13 to be slid within them so that they locate- the housing 13. Although the housing resembles its final form it is not secured together.

This is achieved at the next stage by either injection moulding hot plastics material in and around the preform or by bonding the assembly together. Preferably however plastics is injection moulded and this serves to insulate individual spikes from one another and from the exterior of the housing so formed. Coding lugs are formed on the inner surface of the housing 13 before it is moulded onto the cable. The arrangement so fabricated forms a housing supporting three electrodes each in electrical contact with a separate inner core of a cable.

Assembly of the adaptor 12 will now be briefly described with reference to the aforementioned figures.

A cable 20 on which is to be mounted the adaptor 12 is cut at one end to reveal each of the inner cores. The inner cores are passed through the adaptor insert 103 and each of the individual inner cores are pushed into a groove 103L, 103N and 103E. Each of these grooves corresponds to the live, neutral and earth colours of the inner cores of the cable 20. The underplan view of the insert 15 shows two legs 16 and 16A which receive the grooves 104 and 104A respectively. Spiked contacts 97, 98 and 99 which are connected to electrical contacts 22, 21 and 23 respectively pierce the cables and lock the cables into their respective grooves 103N, 103L and 103E. Depressions 105N, 105L and 105E located in each groove receive the spiked portions of the electrical contacts thereby enabling the insert 103 to fit snugly against the adaptor insert 15.Even without any bonding or adhesive the adaptor insert and insert remain in close proximity to one another because of the gripping nature of the extended legs 16 and 16A. The arrangement is then bonded together using a heated injection moulded injecting system and any crevices or gaps are sealed thereby rendering the outer insert water-tight.

Figures 10A, 10B and 10C show different views of a cable support 50. The support 50 formed from a synthetic plastics material comprises a body having four legs 51A, 51B, 51C and 51D and a generally round body portion 52.

The body portion 52 is slightly raised from the part of the support on which cross pieces 51 are mounted. At the end of each cross piece 51 is a leg 53A, 53B, 53C and 53D. Each leg is supported on the cross piece bearing its initial letter respectively. At the end of each leg 53 there is a slight champfer which acts as a lead in for the housing 13. On the underside of the support 50 there are three pairs of cable locating pins 55L, 55N and 55E. Each pair of pins receives one of the cables in the three core cable namely one of cable live neutral or earth. Between the pins there is an indentation which is preferably a hole moulded in the body 50 at the fabrication stage. This is shown in detail in the part figure. The hole receives a spike which is integral with a sprung or unsprung brass electric contact 13 has lugs set on its perimeter which provide for a unique orientation of each electrical contact within the holder or adaptor. These lugs ease assembly and ensure that the cable engages correctly with the brass electric contact.

It will be appreciated that the above description has been by way of an example only and that variation may be made to the invention. For example the equipment may be utilised as a permanent way of power transmission and the connectors with adaptors may be fixed permanently to a ceiling or wall. Lighting equipment may therefore be used in conjunction with a network of connectors as and when required.

Claims (18)

1. A method of manufacturing an adaptor integral with a cable comprising the steps of: forming a discontinuity in an outer sleeving of a multi-core cable, so as to reveal inner cores, arranging at least one inner core in a predetermined position on a core support, engaging contact means with a conductive portion of each inner core, the contact being supported by contact housing; and bonding the contact housing and bonding the housing to the core support to form the adaptor.

2. A method according to claim 1 wherein the sleeving of a three core cable is cut in a substantially transverse direction, and the sleeving on one side of the cut is moved away from the sleeving on the other side of the cut so as to reveal the inner cores.

3. A method according to claim 2 wherein a guide is provided on the core support to support the contact housing for an adaptor.

4. A method according to claim 3 wherein the contact housing is shaped so that it may only be received in one orientation by the guide on the core support such that specific electrical contacts pierce respective inner cores of the cable.

5. A method according to claim 4 wherein the cable comprises three inner core cables.

6. A method according to claim 5 wherein the core support has three electrical contacts for piercing three core cables such that a first electrical contact contacts a neutral cable, a second electrical contact contacts a live cable and a third electrical contact contacts an earth cable.

7. A method of manufacturing a housing integral with a cable comprising the steps of: forming a discontinuity in an outer sleeving of a multi-core cable, so as to reveal inner cores, arranging individual inner cores in a predetermined position on a core support, engaging contact means with a conductive portion of each inner core, the contact means being supported by a contact housing; and bonding the contact housing to the core support to form the housing.

8. A method according to claim 7 wherein two substantially transverse cuts are formed so as to form a small section of sleeving, the small section of sleeving being removed so as to reveal the inner cores.

9. A method according to claims 7 or 8 wherein guide means is provided on a core support to support a contact housing.

10. A method according to claim 9 wherein the housing is shaped so that it may only be received in one orientation by the guide on the core support such that specific electrical contacts pierce respective inner cores of the cable.

11. A method according to claim 10 wherein the cable comprises three inner core cables.

12 . A method according to claim 11 wherein the core support has three electrical contacts for piercing three core cables such that a first electrical contact contacts a neutral cable, a second electrical contact contacts a live cable and a third electrical contact contacts an earth cable.

13. A method according to any of claims 7 to 12 wherein synthetic plastics material is injection moulded around the contact housing and core support so as to form a housing.

14. A method according to any of claim 13 wherein the housing is shaped to receive an adaptor.

15. An adaptor formed according to the method of claims 1 to 6 wherein electrical contacts of the adaptor for contacting electrical contacts of a housing; the housing being shaped to receive the adaptor; are arranged such that an electrical contact of the adaptor in contact with a solid electrical contact of the housing is a sprung electrical contact; and an electrical contact of the adaptor in contact with a sprung electrical contact of the housing is a solid electrical contact.

16. A method according to claim 1 to 6 and 15 wherein the adaptor has means disposed in it for receiving an adaptor insert in only one orientation.

17. An adaptor formed integrally with a cable according to the method of claims 1 to 6, 15 and 16.

18. A method of forming a housing with a cable substantially as herein described with reference to the Figures.

18. A plurality of housings formed integrally with a cable according to the method of claims 7 to 14.

19. A method of forming an adaptor with a cable substantially as herein described with reference to the Figures.

20. A method of forming a housing with a cable substantially as herein described with reference to the Figures.

Amendments to the claims have been filed as follows 1. A method of manufacturing an adaptor integral with a cable comprising the steps of: forming a cut in a substantially transverse direction in an outer sleeving of a multi-core cable, moving the sleeving on one side of the cut away from the sleeving on the other side of the cut so as to reveal inner cores, arranging at least one inner core in a predetermined position on a core support, engaging contact means with a conductive portion of each inner core, the contact being supported by contact housing; and bonding the contact housing and bonding the housing to the core support to form the adaptor.

2. A method according to claim 1 wherein a guide is provided on the core support to support the contact housing for an adaptor.

3. A method according to claim 2 wherein the contact housing is shaped so that it may only be received in one orientation by the guide on the core support such that specific electrical contacts pierce respective inner cores of the cable.

4. A method according to claim 3 wherein the cable comprises three inner core cables.

5. A method according to claim 4 wherein the core support has three electrical contacts for piercing three core cables such that a first electrical contact contacts a neutral cable, a second electrical contact contacts a live cable and a third electrical contact contacts an earth cable.

6. A method of manufacturing a housing integral with a cable comprising the steps of: forming two substantially transverse cuts in an outer sleeving of a multi-core cable, removing the section of sleeving intermediate said cuts so as to reveal inner cores, arranging individual inner cores in a predetermined position on a core support, engaging contact means with a conductive portion of each inner core, the contact means being supported by a contact housing; and bonding the contact housing to the core support to form the housing.

7. A method according to claim 6 wherein guide means is provided on a core support to support a contact housing.

8. A method according to claim 7 wherein the housing is shaped so that it may only be received in one orientation by the guide on the core support such that specific electrical contacts pierce respective inner cores of the cable.

9. A method according to claim 8 wherein the cable comprises three inner core cables.

10. A method according to claim 9 wherein the core support has three electrical contacts for piercing three core cables such that a first electrical contact contacts a neutral cable, a second electrical contact contacts a live cable and a third electrical contact contacts an earth cable.

11. A method according to any of claims 6 to 10 wherein synthetic plastics material is injection moulded around the contact housing and core support so as to form a housing.

12. A method according to claim 11 wherein the housing is shaped to receive an adaptor.

13. An adaptor formed according to tie method of claims 1 to 5 wherein electrical contacts of the adaptor for contacting electrical contacts of a housing; the housing being shaped to receive the adaptor; are arranged such that an electrical contact of the adaptor in contact with a solid electrical contact of the housing is a sprung electrical contact; and an electrical contact of the adaptor in contact with a sprung electrical contact of the housing is a solid electrical contact.

14. A method according to any of claims 1 to 5 or 13 wherein the adaptor has means disposed in it for receiving an adaptor insert in only one orientation.

15. An adaptor formed integrally with a cable according to the method of claims 1 to 5, 13 or 14.

16. A plurality of housings formed integrally with a cable according to the method of claims 6 to 12.

17. A method of forming an adaptor with a cable substantially as herein described with reference to the Figures.