WO1998038717A1

WO1998038717A1 - Electrical connector assembly

Info

Publication number: WO1998038717A1
Application number: PCT/GB1998/000649
Authority: WO
Inventors: Derek Linaker
Original assignee: Derek Linaker
Priority date: 1997-03-01
Filing date: 1998-03-02
Publication date: 1998-09-03
Also published as: GB9704278D0; AU6629898A

Abstract

An electrical conductor assembly having superimposed conductors (1-3) with terminals (4) projecting on opposite sides is potted in resin within a trough shaped housing (15). The housing (15) has deflectable side walls (17) so that the terminals (4) can be manoeuvered through apertures (20) in the side walls (17), and the terminals (4) are sealed within the apertures (20) by a washer (22) on the inner side of the wall, and a retaining cap (23) which is pushed over the terminal into engagement with the washer (22) on the outer side of the wall.

Description

ELECTRICAL CONNECTOR ASSEMBLY

TECHNICAL FIELD

This invention relates to electrical connector assemblies of the bus-bar type having a plurality of conductors held in spaced relationship one on top of

another with outwardly extending terminals.

BACKGROUND ART

Connector assemblies of this kind are described in GB 2234922B and also WO 96/09669. As specifically described in the latter patent specification the conductors are made from strips of conductive material cut to define an

elongate body with the terminals projecting transversely on opposite sides. The conductors are held in spaced relationship and are insulated by 'potting' in a solid body of synthetic polymeric material. This potting is achieved by positioning the conductors in an open trough-shaped housing and then pouring resin from above into the housing. The terminals project freely through slots in

side walls of the housing and are sealed relative to the housing, to prevent escape of the resin prior to setting, by means of specially designed elongate closure members or grommets which extend within the side wall slots from the edge of the open top of the housing to the position of the projecting terminals.

Also, the conductors project from one end of the housing through sealed slots in an end cap to provide main input connections.

With this known arrangement a specially constructed housing and sealing constructions are required whereby the potting process is relatively complicated and costly.

DISCLOSURE OF THE INVENTION

An object of the present invention is to provide a potting process of

improved simplicity and reduced cost. According to the invention therefore there is provided a method of potting a conductor assembly of the kind comprising a plurality of conductors in spaced relationship one on top of another with terminals extending outwardly from the

sides thereof, wherein the conductors are positioned within a housing with the

terminals projecting through apertures in at least one side wall thereof and settable resin is poured into the housing through an opening therein, characterised in that the housing is formed as a deflectable structure whereby the (or each) said side wall is movable from an outer assembly position to an

inner resin-retaining position, the terminals being located and sealed relative to the (or each) side wall in the inner position thereof by means of a washer and a retaining member which fit around each terminal respectively on the inner and outer sides of the wall.

With this arrangement, the conductor assembly can be inserted into the housing with the (or each) side wall deflected to its outer position, and the

terminals can then be inserted through the apertures as the (or each) side wall is deflected to its inner position. In this way, the conductor assembly can be positioned within the housing in a particularly convenient manner, and the housing can be formed as a simple structure without requiring costly and complex constructions. The sealing washers and retaining members can give

good sealing around the terminals and also can ensure or assist secure location of the terminals and walls during pouring and setting of the resin, in a particularly simple and convenient manner. The housing may be of trough shape and it may be filled through an open

mouth thereof with the housing level and the ends appropriately covered.

Alternatively and preferably however, the housing is of trough shape and, in the inner position of the (or each) deflectable wall, after insertion of the conductor assembly, the mouth is covered to define an open ended tubular housing. This open-ended tubular housing can be filled in upright position

through an uppermost open end, with the opposite bottom end covered or simply resting on a support surface. With this arrangement, where it is required to allow for free projection from the housing of ends of the conductors to provide input connections, this can be readily achieved, without need for any sealing end constructions, by arranging the conductors with such ends projecting upwardly out of the open uppermost end.

The deflection of the (or each) side wall may be achieved through the use of flexible material and/or by means of a hinge joint between the side wall and an adjoining wall of the housing. A plastics material such as PVC or other suitable insulating material is preferably used.

Where the housing is trough shaped and has a cover as aforesaid, this cover may comprise a plate, suitably formed from the same material as the trough part of the housing, and the plate may be retainably engageable with the side walls, e.g. via grooves on the plate slidably engageable with shaped edges of the trough side walls.

With regard to the said washer for each terminal, this is preferably formed

from a suitable resilient material such as rubber or elastomeric plastics to facilitate sealing. Preferably also the washer has an extension thereto which extends through the aperture in the side wall, from the inner to outer sides thereof, around the terminal.

A groove or other locating structure may be provided adjacent the

extension for locating engagement with the respective side wall around the respective aperture so that the washer does not tend to be pushed out inwardly during fitting.

Preferably also, the washer is arranged to engage the terminal so as to be securely located relative thereto. This may be achieved by provision of a narrow waisted region on the terminal into which a slot in the washer forms a

snap-fit. Other kinds of cooperable configurations may also be used.

With regard to the outer retaining member, this may be in the form of a push-on cap which frictionally engages the free end portion of the terminal and preferably forms a tight fit therewith so as to seal relative to the terminal and

prevent, or limit ingress of resin. The retaining member may be formed from rubber or elastomeric plastics like the washer. The retaining member may engage the washer by a tight fit and/or by interengagement of cooperable configurations (such as by engagement of a lip on the washer with an inner

surface or groove in the retaining member) to effect retention and/or sealing

therebetween.

The retaining member may act to hold, or assist in holding the respective

side wall in the inner position, although alternatively this may be achieved by

another structure, or structures, such as the aforementioned cover.

The apertures to receive the terminals may be of any suitable form.

Preferably however, the apertures are peripherally closed, i.e. they do not open

to a side edge of the housing, and most conveniently round apertures may be used.

The conductor assembly may be of any suitable kind but is preferably as

described in the aforementioned patent specifications being formed from strips

of conductive material which are cut and bent to define the terminals.

As above mentioned, the conductors may have input connections

provided by end parts which project from an end of the housing. In this case, in order to prevent possible shorting between adjacent such end parts by

inadvertent bridging contact with a conductive body, one or more, preferably one

intermediate, such end part may be enclosed within an insulating sleeve.

Alternatively or additionally, all such end parts may be enclosed when not in use

within a removable shaped insulating end cap which conveniently may be held

in position by a tie.

There may be three conductors and if desired there may also be linking additional (e.g. neutral) conductors, although any other suitable arrangement

may be used.

Where a neutral conductor is provided this may be defined by conductive

strips running along opposite sides of the housing internally thereof with one or

more internal bridging links between such strips. As described in WO 96/09669,

the strips may be formed from folded metal, and if desired the strips may have

terminals which project from the housing in like manner to live conductors. The

links between the strips may be defined by tubes or rods which at each end

incorporate or are connected to threaded sections projecting externally of the

housing with which nuts can be engaged to hold the links in secure conductive

contact with the strips and also to provide neutral input connections.

Conveniently, these projecting threaded sections can be passed through

preferably circular apertures in the housing side walls generally in like manner

to the aforesaid terminals. Sealing and location relative to the side walls during

pouring and setting of the resin may be achieved by inner and outer washers

between which the side walls are clamped by the aforesaid nuts. These

washers may be conductive, and the outer washer may be stepped with an extension of reduced diameter which penetrates the aperture in the side wall. BRIEF DESCRIPTION OF THE DRAWINGS

The invention will now be described further by way of example only and

with reference to the accompanying drawings in which:-

Fig. 1 is a diagrammatic transverse cross-section of a conductor assembly within a housing ready for potting in accordance with

one embodiment of the invention; Fig. 2 is a sectional view at right angles to Fig. 1 to a larger scale of a

detail of the arrangement of Fig. 1 ;

Fig. 3 is a longitudinal sectional view of an end part of the potted assembly of Fig. 1. Fig. 4 is an end view of an outer retaining cap, from the top of Fig. 2.

DESCRIPTION OF THE PREFERRED EMBODIMENT

Fig. 1 shows an assembly of three horizontal live conductors 1 , 2, 3 one on top of the other. Each conductor 1, 2, 3 is formed by cutting and bending from a copper sheet and has an elongate body and terminals 4 projecting outwardly on opposite sides. The elongate bodies terminate level with each other at one end. At the opposite end the elongate bodies have projecting end

parts 5-7 (Fig. 3) which define main live input connections.

Fig. 1 also shows two opposed vertical neutral conductors 8 also formed by cutting and bending from a copper sheet. Each conductor 8 has a strip-shaped elongate body with terminals 9 projecting upwardly and then horizontally outwardly at end regions thereof alongside the terminals 4.

These strip shaped bodies are linked by conductive tubes 10 at spaced positions along the length thereof, held in contact with the strips 8 by means of a rod 11 passed through the tube 10 and through holes in the strips 8 and engaged with nuts 12 at opposed threaded end parts 13 thereof. A neutral input connection 14 is attached in use to one threaded end part 13.

Reference is made to WO 96/09669 for a more detailed description of the live conductor assembly 1-3 and the neutral conductors 8.

The live conductor assembly 1 -3, and the neutral conductors 8 are potted within a housing formed from an insulating deflectable plastics material such as

PVC.

The housing has a one-piece trough shaped part 15 made up of an

elongate top 16 and two flat rectangular side walls 17. The top wall 16 is shaped to define an elevated central section 18 and two inclined side sections 19, each section 18, 19 having edge retaining slots for insertion of an identification card or the like.

Each side wall 17 has a row of aligned equally-spaced circular

apertures 20, one for each terminal 4, 9, and also spaced apart lower circular apertures 21 for the threaded end parts 13 of the rods 11. The terminals 4, 9 and threaded end parts 13 are sealed and located relative to the side walls 17 by means of inner washers 22 and outer retaining caps 23 for the terminals 4, 9, and inner and outer washers 24, 25 for the end parts 13, as described in more detail hereinafter.

As shown in Fig. 1 , the open top of the trough 15 is closed by a plate 26, formed from the same material as the trough part 15, and which extends along the entire length of the trough part 15. This plate 26 retainably engages the trough part by longitudinal sliding engagement of grooves in the edge regions of the plate 26 with complementary shaped configurations of the nature of beads

along the edges of the side walls 17.

The arrangement so far described is assembled as follows:

The trough-shaped housing part 15 is located in a jig with the top plate 16

facing downwards and the side walls 17 directed upwards and deflected

outwards in spiayed-apart angular disposition. The live conductor assembly 1-3

and the strips 8 are positioned between the side walls 17 so that the terminals

4, 9 are aligned with the respective apertures 20, it being understood that the side walls 17 are deflected outwardly sufficiently to allow manoeuvring of the live

conductor assembly 1 -3 into position.

As shown in Fig. 2, the terminals are shaped so as to provide a narrow

waist position 27 at the base of each terminal, and the outermost end portion of

each terminal is of reduced width appropriate to its intended use (i.e. to fit the size of circuit breaker or switch or like to be engaged therewith).

Around the base of each terminal 4, 9 on the inner side of the respective

side wall 17 there is a respective said inner washer 22 which comprises a

circular elastomeric disc 28 with a central rectangular slot 29 and an integral cylindrical collar extension 30 with an end circumferential lip 31. A groove 31a is defined between the disc 28 and the extension 30.

The washer 22 fits on the terminal 4,9 with the slot 29 a snap fit

engagement with the waist portion 27 and the collar 30 facing towards the face

end of the terminal. When the side walls 17 are released from the jig and allowed or

compelled to move inwardly to the parallel vertical positions shown in Fig. 1 , the

washer collars 30 fit closely within the apertures 20 with the disc body 28 of

each washer 22 in contact with the inner side of the side wall and with the collar

30 projecting through the aperture 20 with the lip 31 on the outer side of the wall

17. The side wall fits within the groove 31 a to help prevent the washer being

pushed inwardly out of the aperture in the side wall.

The outer retaining cap 23 for each terminal 4, 9 comprises a disc body

32 with a cylindrical rim 33.

There is a rectangular slot 34 of like dimensions to the slot 29 in the

centre of the disc body 32 and there is an integral rectangular hollow projecting

portion 35 in communication with, and having the same internal cross-section

as the slot 34.

The cap 23 fits on the outer narrow portion of the terminal 4, 9 and is a

close fit so that it can be pushed on, with the side wall in its inner vertical

position, until the rim 33 abuts the side wall and is a tight push fit around the

extension 30, whereby the side wall 17 is held tightly between the rim 33 of the cap 23 and the disc body 23 of the washer 22. A groove 33a is defined within

the rim, 33 and this snap fits with the lip 31. This holds the terminal 4, 9

securely in position relative to the side wall 17, seals the terminal 4, 9 relative

to the side wall 17, and tightly encloses the projecting end portion of the terminal

4, 9. Referring to Fig. 1 , between the strips 8 and the inner faces of the side walls 17 there are the inner metal washers 24, and the outer metal washers 25

are fitted on the outside of the side walls 17 around the threaded end parts 13

of the rod 11. These outer washers 25 are stepped and have a portion of

reduced diameter which is a close fit within the aperture 21.

With the side walls 17 in the vertical position nuts 12 are tightened on the threaded end parts 13 so as to clamp the side walls 17 tightly between the inner and outer washers 24, 25 thereby to locate the strips 8 relative to the side walls

17 and seal the apertures 21. The bottom plate 26 is then fixed in position.

The housed assembly so far described is then positioned longitudinally upright with one end (the aforesaid end at which the conductors 1-3 terminate level) on a flat support surface (not shown). As mentioned the conductors 1-3

have connection parts 5-7 which project from the opposite end of the housing, which end is now uppermost. Resin is poured into the space 41 in the housing through this uppermost end until level with such end, and the resin is then allowed to set.

When set, the conductors 1-3, 8 are securely potted within the housing and the resin forms a level end surface at each end, without need for any end sealing plate.

Leakage around the terminals 4, 9 is prevented by the sealing structures already described. Referring to Fig. 3, the central connection part 7 projecting at one end is

sheathed with an insulating sleeve 38 and this may be bonded to the set resin,

in the housing space 37, at its inner end, suitably by incorporation into the resin prior to setting thereof.

A thin vacuum-formed plastics protective end cap 39 is positioned over the projecting connection parts 5-7 and is held in position by a tie 40, when the

connection parts 5-7 are not in use. The sleeve 38 is of flattened shape (like the

terminal 7) and has edge projections (not shown) which engage guide slots in the inner side walls of the cap 39. In use, the cap 39 can be removed as also are the caps 23 on the terminals 4, 9.

With the arrangement described the conductors 1-3, 8 can be potted in a particularly simple and inexpensive manner in so far as it is not necessary to use a complicated specially constructed housing. It is of course to be understood that the invention is not intended to be restricted to the details of the above embodiment which are described by way of example only.

Claims

1. A method of potting a conductor assembly of the kind comprising a plurality of conductors in spaced relationship one on top of another with

terminals extending outwardly from the sides thereof, wherein the conductors

are positioned within a housing with the terminals projecting through apertures in at least one side wall thereof and settable resin is poured into the housing through an opening therein, characterised in that the housing is formed as a

deflectable structure whereby the (or each) said side wall is movable from an outer assembly position to an inner resin-retaining position, the terminals being

located and sealed relative to the (or each) side wall in the inner position thereof by means of a washer and a retaining member which fit around each terminal respectively on the inner and outer sides of the wall.

2. A method according to claim 1 characterised in that the housing is trough shaped and is filled through an open mouth thereof with the housing level and

ends thereof covered.

3. A method according to claim 1 characterised in that the housing is trough shaped and is filled in upright position through an uppermost open end with an open mouth of the trough shaped housing covered.

4. A method according to claim 3 characterised in that the open mouth is covered with a plate retainably engageable with the side walls.

5. A method according to any one of claims 1 to 4 characterised in that the said washer has an extension thereto which extends through the aperture in the side wall from the inner to outer sides thereof, around the terminal.

6. A method according to claim 5 characterised in that a groove is provided

adjacent the extension for locating engagement with the respective side wall

around the respective aperture.

7. A method according to claim 5 or 6 characterised in that the washer and terminal have cooperable configurations for locating purposes.

8. A method according to claim 7 characterised in that the configurations comprise a waisted region on the terminal engageable with a slot in an end face of the washer.

9. A method according to any one of claims 1 to 8 characterised in that the outer retaining member comprises a push-on cap which frictionally engages the free end portion of the terminal.

10. A method according to claim 9 characterised in that the retaining rromber retainably engages the washer by a tight fit.

11. A method according to claim 9 or 10 characterised in that the retaining member retainably engages the washer by interengagement of cooperable configurations.

12. A method according to any one of claims 1 to 11 characterised in that the

apertures are peripherally closed.

13. A method according to claim 12 characterised in that the apertures are round.

14. A method according to any one of claims 1 to 13 characterised in that the conductor assembly is formed from strips of conductive material which are cut

and bent to define the terminals.

15. A method according to any one of claims 1 to 4 characterised in that the conductors have input connections provided by end parts which project from an end of the housing and at least one said end part is enclosed within an

insulating sleeve.

16. A method according to claim 15 characterised in that all end parts are

enclosed within a removable insulating end cap.

17. A method according to any one of claims 14 to 16 characterised in that there are three conductors.

18. A method according to claim 17 characterised by the provisions of an additional neutral conductor defined by conductive strips running along opposite sides of the housing internally thereof with one or more bridging links between the strips.

19. A potted conductor assembly made by the method of any one of claims 1-18.