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-topped 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

closure members or grommets. 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 an open-topped housing with the terminals projecting through slots therein and settable resin is poured into the housing through the open top thereof, characterised in that the housing is formed from flexible sheet material with the said slots therein, said

sheet material being located around the conductor assembly in a first outwardly deflected state in which the said slots are disposed outwardly of the terminals, and said sheet material then being moved to a second inwardly deflected state

in which the sheet material forms an open-ended tubular structure located with the terminals projecting through the slots as aforesaid

With this arrangement, the conductor assembly can be readily positioned

longitudinally relative to the sheet material which forms the housing when this

is in its first state, and the terminals can then be located through the slots when the sheet is in its second state In this way, the conductor assembly can be positioned within the housing in a particularly convenient manner, and the

housing can be a simple tubular structure without requiring costly and complex

constructions. The deflectable nature of the sheet material forming the tubular

structure can by itself give good location and sealing around the terminals without need for sealing grommets or washers or caps or the like although these may be used if desired. Thus, the sheet material of the tubular structure may be held in position relative to the projecting terminals in the said second state by

means of end devices pushed on to the ends of the terminals to act as locating

abutments. The said devices may comprise washers or grommets or caps which seal the slots with the terminals projecting therethrough. The said devices may engage locating grooves or notches in the terminals.

In one embodiment the flexible sheet material is in the form of an opened out sheet with opposite free edges in the said first state, and the free edges are joined together to form the said tubular structure in the said second state. The joining of the edges may be achieved in any suitable manner e.g. by bonding or

abutment interlocking of configurations or otherwise, preferably in a sealing manner and preferably also in a structural retaining manner, although other

arrangements are possible.

In an alternative embodiment, said sheet material defines said

open-ended tubular structure in both said first and second states but is resiliently deflectable between the said states so as to have a transverse dimension which is respectively greater than and less than a corresponding

maximum external dimension of the projecting terminals in the first and second

states.

The tubular housing can be conveniently filled through an open top end

thereof with the housing upright and the opposite bottom end thereof covered _.

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 top end.

The tubular structure may be of circular cross-section in the said second

state although it may also be generally oval or of other cross-section.

In the case where a deflectable pre-formed tubular structure is used, this

may be generally of oval cross-section in the said first state and of circular cross-section in the said second state.

After deflection and positioning of the conductors the pre-formed tubular structure may be allowed to return to its non-deflected state. For example, a circular cross-section structure may be allowed to return to circular cross-section

after deflection to an oval cross-section. Alternatively, the pre-formed tubular structure may be deflected, after positioning of the conductors, to reduce the transverse dimension to be smaller

than its non-deflected dimension, by compression of the structure. This may be

necessary or desirable to ensure that the terminals project adequately from the housing in the final potted state. Thus, a circular cross-section structure may be

compressed to a generally oval cross-section. The housing may be held in the

compressed state in any suitable manner, conveniently by the use of grommets, washers or caps or the like, such as those above mentioned, which bear against

the outer surface of the housing and interlock with grooves or notches or other

configurations on the conductors e.g. at inner end parts of the terminals

Preferably the tubular structure is formed from a resiliency deflectable plastics material such as PVC or other suitable insulating material

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

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

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 an end view of a conductor assembly within a housing ready for potting in accordance with one embodiment of the invention,

Fig. 2 is a diagrammatic perspective view showing a sheet

and a conductor assembly in accordance with a second embodiment.

Fig. 3 is a diagrammatic perspective view of a potted conductor

assembly made in accordance with either embodiment; and

Fig. 4 is a diagrammatic perspective view of a detail of the arrangement

of Fig. 3

DESCRIPTION OF THE PREFERRED EMBODIMENTS

Fig 1 shows an assembly of three 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 7 (Fig 3)

which define main input connections

Reference is made to WO 96/09669 for a more detailed description of this conductor assembly

This conductor assembly is potted within a cylindrical plastics tube 5

which is open at each end and which is formed from insulating, resiliently deflectable plastics material such as PVC The tube 5 has slots 6 therein to receive the terminals 4

The maximum outside dimension of the terminals i e the transverse

separation of the ends of opposite terminals 4, is greater than the diameter of the tube 5 For example the terminal separate may be 132mm whereas the

diameter of the tube 5 may be 100mm

The conductor assembly is inserted longitudinally within the tube 5 after

first deflecting the tube 5 to adopt an oval shape as shown in broken lines at 8 in Fig 1 The assembly is positioned with the level ends of the elongate

conductor bodies near to one open end of the tube, and with the projecting end

parts 7 extending beyond the other open end of the tube 5 The tube 5 is then

released so that it returns to its non-deflected circular shape whereby the

terminals 4 then extend through the respective slots 6

Sealing grommets or caps 9 (Fig 4) are pushed onto the terminals 4 so as to extend into the slots 6 and thereby seal the terminals 4 relative to the slot

sides

As shown in Fig 4, the caps 9 have projections 10 at their inner ends which can snap fit with grooves or slots 11 around the base of each terminal 4 in order to hold the caps 9 in position relative to the terminals 4

In order to achieve this snap fit it is necessary to deflect the sides of the

tube 5 inwardly to adopt a generally oval shape as shown in broken lines at 12 in Fig. 1 , whereby the deflected tube presses resiliency against the grommets

to form a secure seal

The arrangement so far described is mounted in upright disposition, as

seen in Fig. 3, with the bottom end of the tube closed by a surface on which it

is placed.

The tube 5 is then filled from the top with a settable resin 13 and the resin

is allowed to set.

The conductor assembly is thereby potted within the tube 5 with the capped terminals 4 extending through the slots 6 and the end parts 7 extending

out of the top of the tube 5. The tube 5 is held in the inwardly deflected oval

state by the shape of the set resin whereby adequate projection of the terminals 4 is ensured The caps 9 can be detached or cut away prior to use

With this arrangement the conductor assembly can be potted in a

particular simple and inexpensive manner in so far as it is not necessary to use

a complicated specially constructed housing

An alternative embodiment is shown in Figure 2 Here a rectangular sheet 15 of resiliently flexible plastics material is used instead of the preformed tubular structure of Figure 1

As shown in Figure 2, the sheet 15 has slots 16 (only some of which are shown) and is initially opened-out in flat condition with free opposite side edges 17, 18 The sheet 15 is wrapped around the conductor assembly 19 (which is of like form to that shown in Figure 1 ) so as to bring the edges together

in the direction of arrow 20 In doing this, the terminals 4 pass through the slots 16 and the sheet 4 defines a tubular structure of circular cross-section as

shown in Figure 3

Sealing grommets or the like are pushed onto the projecting end of the

terminals, as described above in connection with the first embodiment and

Figure 4, so as to seal with slots 16 between the terminals 4 and the sheet 15, and so as to hold the sheet 15 in position relative to the terminals 4

The free edges 17, 18 of the sheet 15 are joined together to complete the

tubular structure This may be achieved in any suitable manner The edges 17, 18 may be bonded together or held together by interlocking edge

configurations or by an attached sealing strip The arrangement may be such

that the edges 17, 18 are both sealed together and are mechanically held

together against separation thereof. Alternatively the edges may simply abut or overlap and may be held together e.g. by means of a band tightened around the tubular structure or otherwise.

The tubular structure can then be filled with resin in like manner to the first embodiment.

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.

Thus, for example, although a three conductor assembly is shown, other arrangements are possible and, in particular, it is possible to provide a separate

linking neutral conductor, e.g. as indicated in broken lines at 14 in Fig. 1.

With regard to the terminal arrangement shown in Figure 4, instead of the inwardly positioned locating recesses 11 , which may be undesirable in so far as they constitute removal of material and consequent reduction in current-carrying

properties, it is possible to use barb conformations on opposite sides at or immediately adjacent the outward free end edge of the terminal, with the cap 9, or other device, being appropriately formed to coact with these.