AU609486B2 - Terminal unit - Google Patents

Description

COMMONWEAL T H OF A U S T R A L I A PATENTS ACT 1952 COMPLETE SPECIFICATION (Original) FOR OFFICE USE 60 9 48 6 Class Int. Class Application Number: Lodged: Complete Specification Lodged: Accepted: Published: .P*i*ority: :.Related Art: 0 0 This document contains the amendments made under Section 49 and is correct for printing.

a a, oa a 0 60 oime of Applicant: Address of Applicant: a Actual Inventor(s): Address for Service: KRONE AKTIENGESELLSCHAFT Beeskowdamm 3-11, D-1000 Berlin 37, Federal Republic of Germany DAVIES COLLISON, Patent Attorneys, 1 Little Collins Street, Melbourne, 3000.

Complete specification for the invention entitled: "TERMINAL UNIT" The following statement is a full description of this invention, including the best method of performing it known to us 1 if ka memoer or me rrm or UAVMit COLLISON for and on behalf of the Applicant).

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it Davies Collison, Melbourne and Canberra.

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p o p p p TERMINAL UNIT This invention relates to a terminal unit.

*e p pp a op C p p p In accordance with one aspect of the present invention there is provided a terminal unit comprising an elongate mounting frame demountably affixed at one end to a frame carrier, the mounting frame carrying, at two opposite sides thereof, electrical contact portions to permit electrical connections to be made to either side of the frame, the frame carrier being mountable in a condition whereby the mounting frame extends upwardly therefrom to receive electrical conductors which extend upwardly to the elect.rical contact porions on the 'n a Anotner "ci/4e byrn frame, the frame being pivotal,dee~- flexure of said conductors, and adjacent the frame carrier, by demounting of the frame from the frame carrier

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4 3 whereby, by such pivoting, access from a location at one said side of the terminal unit may be had to electrical connections made to a said contact portion at a remote said side of the frame.

The unit may incorporate connectors of the number l57378/? kind described in our copending applicationAentitled "Electrical Connector" lodged the same day as the present application.

The invention is further described with reference to the accompanying drawings in which; Figure 1 is a perspective view of a terminal unit constructed in accordance with the invention.

a e Figure 2 is an axial cross section of a frame carrier forming part of the terminal unit in Figure 1.

Figure 3 is a side view of the frame carrier of Figure 2.

Figure 4 is a plan view of the frame carrier of Figure 2.

Figure 5 is a front elevation of a mounting frame incorporated into the unit of Figure 1.

Figure 6 is a side view of the mounting frameof Figure 6.

Figure 7 is a plan view of the mounting frame of Figure 6.

Figure 8 is an enlarged fragmentary horizontal cross- 5 R' O^

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v r section showing the interconnection between the frame carrier of Figure 2 and the mounting frame of Figure Figure 9 is a perspective view of one the electrical connector of the invention; ra Figure 10 is a plan view of the connector of Figure 9; Figure 11 is a side view of the connector of Figure 9; Figure 12 is a front elevational view of the ro connector of Figure 9; Figure 13 is a cross section on the line 13-13 in Figure 11; Figure 14 is a cross section on the line 14-14 in 0 Figure 12; Figure 15 is a perspective view showing disconnection contacts which are capable of incorporation into the connector of Figure 9; Figure 16 is a perspective view of a connection contact capable of incorporation into the connector of Figure 9; Figure 17 is a plan view of an over-voltage protection unit capable of being inserted into the connector of Figure 9; Figure 18 is a side view of the over voltage protection unit of Figure 17; .i .in figure 17, of the over-voltage protection unit of 1 Figure 17; Figure 20 is a perspective view of the internal components of the over-voltage protector unit of Figure 17.

ff .oo Figure 21 is a plan view of a connector member of the a o over-voltage protector unit; 0 Figure 22 is a side view of the connector member of Figure 21; oo000 Figure 23 is an end view of the connector member of Figure 21; Figure 24 is a diagram showing a first contacting position in which a contact element of the over-voltage protection unit of Figure 17 engages two pairs of the contacts of the connector of Figure 9; Figure 25 is a diagram showing a second contacting position in which the contact element of the over-voltage protection unit of Figure 17 engages one pair of contacts of the connector in Figure 9; Figure 26 is a diagram showing a third contacting position in which the contact element of the over voltage protection unit of Figure 17 engages another pair of contacts of the connector of Figure 9; Figure 27 is a plan view of a plurality of terminal rl 6 units arranged in a telecommunications pillar and having connectors inserted therein, with some of the units also having over voltage protection units attached thereto.

SThe terminal unit 10 shown in Figure 1 is designed to permit interconnection between cable pairs associated with particular telephones or lines :to a telephone exchange.

The unit 10 comprises a mounting frame 12 which is in the form of an elongate channel-like o structure mounted on a frame carrier 14.

The mounting frame 12 is shown in more detail in Figures 5, 6 and 7 as comprising a central ooo lengthwise extending web portion 16 with opposed side flanges 18, 20. The web portion 16 is provided with two lengthwise extending rows of apertures 22, these apertures being of rectangular configuration.

Apertures 22 receive electrical connectors 24 r ro described in detail later. There are, then, two rows of these connectors supported on the frame 12, one row adjacent each of the flanges 18, The frame carrier 14 is, as shown in Figure 2, designed to fit into the base 28 of a telephone cross-connection unit which normally, rests on a ground surface. The carrier 14 has an upper portion which is then positioned above the base 28, and a downwardly depending cylindrical portion 32. The portion 32 is set into an opening 26 in the base 28.

A cable 34, such as an underground cable, extends upwardly into the carrier 14 through the portion 32.

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F I t .1 *l 6 6* 6 0 6 a 6 6o 6 64 6 6 6 6 *6 66 6 A heat-shrunk tube 36 is provided around the portion 32, at its lower end, and around a portion of the cable 34 where this enters the portion 32 of the carrier 14. This tube 36, together with suitable sealing compound 38 which is positioned within the carrier 14 (and particularly within the portion 32 thereof), provides a seal around the cable 34 where this enters the carrier 14. The gap between the exterior of the portion 32 and the periphery of the opening 26 is sealed by a resilient O-ring The cable 34 includes numerous cable pairs 42 and these extend upwardly through the sealing compound 38 and into the carrier 14 itself to make interconnections with individual ones of the connectors 24 on the frame 12.

As particularly shown in Figure 5, the central web portion 16 has, at its lower end, a central cut-out 44 so that to either lateral side of the cut out, the web portion 16 defines downwardly depending legs 46, 48. Also, at the inner edges of the legs 46, 48, the web portion 16 is deformed to define respective fingers 50, 52 which extend normally to the median plane of the web portion 16 and to the opposite side of the web portion 16 to the side to which the flanges 18, 20 extend. The legs 46, 48 also have respective rectangular apertures 54, 56 therein.

The upper portion 30 of the frame carrier 14 has, at opposite sides thereof, retaining structures 58, 60 which cooperate with the legs 46, 48 and the fingers 50, 52 to releasably retain the mounting 1 A r 0 0 ee «o 9 00* 0 o .ao oo 0 o 0 0 o 09 S0 0 0 0 0 0 sadnan 00 00« 00* o a 9 0 0 0 fzame 12 on the frame carrier 14. The structures 58, are generally similar and the following description of the structure 60 made with particular reference to Figure 8 is to ie understood as being applicable to the structure L8, like reference numerals relating to like components of the two structures. In particular, the structure 60 includes a horizontally extending pocket 62 which is sidewardly open but, as shown by broken lines in Figure 3, is closed at upper, lower and inner ends thereof by wall portions 62a, 62b, 62c of portion of the frame carrier 14. The pocket 62 is also closed at either lateral side by an inner side wall portion 62d formed on portion 30 and outer side wall portion 62e formed on portion 30. The side wall portions 62d, 62e are best shown in Figure 8. A tongue 64 is formed integrally with the remainder of the portion 30 of carrier 14, being interconnected on thb, wall 62e at a location remote from the sidewardly open entrance 62f (Figure 8) of the pocket 62. From the position of interconnection, the tongue 64 extends forwardly, adjacent to but spaced from the wall portion 62e, to an outer end 64a of the tongue.

The inner face of the tongue 64 has a latching abutment 64b thereon and the spacing between the abutment 64b on the tongues of the two structures 58 and 60 is so arranged as to enable a latching action to be achieved when the mounting frame 12 is assembled to the frame carrier 14. More particularly, Figure 8 shows the positioning of the mounted frame 12 relative to the structure 60. The finger 52 is dimensioned so as to correspond to the shaping of the pocket 62 and is shown as being i

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O 0 *0 9 O 00 9090ft 0 0Q o a9 0 90 o oa o ca oo 0 0 00 9 9 90 0 0 9 received neatly within the pocket 62. At that same time, the tongue 64 extends through the aperture 56 in the leg 48 of the frame 12. The abutment 64b is located so that a portion of the leg 48 between the aperture 56 and the finger 52 is retained between the abutment 64b and the "forward" or outer end 65 of the wall portion 62e, at the entrance 62f to pocket 62.

The spacing between the opposed surfaces of the abutments 64b on the tongues 64 associated with respective structures 58 and 60 is arranged to be somewhat less than the spacing (Figure 5) between opposed inner edges of the apertures 54, 56. Thus, in order to assemble the frame 12 onto the frame carrier 14, the frame 12 is first positioned in upright disposition with the legs 46, 48 adjacent to, but outboard of the free ends 64a of the tongues 64 on structures 58, 60. Then, the frame 12 is advanced horizontally towards the frame carrier 14 so that the tongues 64 of the structures 58, 60 enter the respective apertures 54, 56 on the legs 46, 48. At the same time, the fingers 50, 52 are entered into the pockets 62 associated with the respective structures 58, 60. As this motion continues, the inner edges of the apertures 54, 56 strike inner inclined surfaces 66 on the abutments 64b so distending the outer ends of the tongues 64 away from each other. This motion continues until the legs 46, 48 pass the abutments 64b, and abut against outer ends 65 of the wall portions 62e of the two structures 58, 60. As this occurs, the legs 48 pass the abutments 64b, whereupon the outer ends of the tongues 64 are moved back again towards each other under natural resilience thereof, to assume the

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position shown in Figure 8 at which the legs 46, 48 are captured in the structures 58, It is possible to remove the frame 12 from the frame carrier 14 by manually outwardly distending the tongues 64 of the two structures 58, 60 one relative to the other to permit the abutments 64b to pass through the apertures 54, 56, whereupon the frame 12 can be withdrawn, accompanied by withdrawal of the fingers 50, 52 from the pockets 62.

o When the frame 12 is in its mounted position on the carrier 14, the fingers 50, 52 ensure that the S' mounting frame 12 is retained in a fashion preventing substantial movement relative to the frame carrier ooo 14. In particular, upward movement of the mounting frame 12 relative to the frame carrier 14 is I prevented by interengagement between the fingers 52 and respective wall portions 62a of the structures 58, 60. Similarly, downward movement is prevented by engagement between the fingers and the wall portions 62b of the structures 58, 60, whilst horizontal inward or outward movement relative to the carrier 14 is precluded by the described capturing of the legs 46, 48 between the abutments 64b and the outer ends of the walls 62e on the respective structures 58, One connector 24 is shown in more detail in Figures 9 to 14 as comprising two electrically insulative moulded plastics body sections 24a, 24b secured together. These are in the form of like plastics mouldings which are snap fastened together.

In the following description, like parts of sections r 1* 11 24a, 24b are designated by like reference numerals.

Thus, each body section includes a main body portion from which extend four guides in the form of guide projections 72, 74, 76, 78. As shown in transverse section of the connector, the body portions 70 are of rectangular cross-section corresponding to the rectangular cross-section of the apertures 22 in the mounting frame 12, but being of slightly lesser dimensions so as to permit insertion of a connector 24 into a respective aperture 22 by movement in the lengthwise direction of extent of the connector 24, ti designated as corresponding to the axis noted in Figure 9. The body portions 70 together define a a "casing 75 (Figure 10) from which the projections 72, 74, 76, 78 extend at either end.

Oo0 By means described later, the two sections 0 °24a, 24b are assembled together with the body portions 70 in abutment so that the projections 72, 74, 76 on each extend in opposite directions away from the plane of abutment, as mentioned. The 0:o relative orientation of the section 24b with reference to the section 24a in the assembled condition of the two sections may be understood by reference to the axes and which are mutually perpendicular to each other and noted in SFigure 9. As mentioned, the axis corresponds to the direction of extent of the projections 72, 74, 76, 78. The axis is a "transverse" dimension of the connector and axis is a vertical or upright axis. Relatively speaking, the section 24a would be oriented in the same fashion as the section 24b, when viewed in Figure 9, if it were rotated through 1800 about the axis shown.

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such portion is provided with two transversely extending and co-planar flanges 80, one at the "upper" 'iajor face thereof and another at the "lower" major face thereof. Flanges 80 on section 24a abut with and are aligned with flanges 80 on the section 24b.

,V The connector 24 may be mounted on the mounting frame 12 by insertion of the connector through an aperture 22 such that the projections 72, 74, 76, 78 at either end thereof are first passed through the aperture until the flanges 80 on the respective section 24a or 24b abut with the surface of the central web portion 16 surrounding that aperture.

Each of the sections 24a, 24b is provided at either lateral side with resiliently deformable latching structure 81 including a tongue 82. These tongues have inclined outer surfaces 84 and, during insertion of the connector into an aperture 22 the side surfaces of the aperture 22 at first strike the surfaces 84 on the tongues 82 of that one of the sections 24a, 24b which is first passed into the aperture 22, thus to inwardly resiliently deform these tongues 82 until, under continued insertion movement, and immediately before the flanges 80 abut the central web portion 16 of the mounting frame 12, the tongues 82 pass through the aperture to an extent that the surfaces 84 are entirely cleared through the aperture 22 and inward steps 86 of the tongues 82 also pass through the aperture. Then, the tongues 82 13 may spring outwardly, since they are no longer engaged by the side edges of the aperture, the connector then being held in position by capturing of part of the central web portion 16 surrounding the aperture 22 between the steps 86 and the flanges This action is similar, regardless of whether section 24a or section 24b is first passed through the aperture 22.

Free ends 82a of the tongues 82, remote from the surfaces 84 may, however, be inwardly sprung o, towards each other so as to cause the surfaces 84 to likewise move inwardly to an extent sufficient to o o enable tongues 82 to pass through the aperture 22, on following outward movement of the connector 24 o o relative to the web portion 16 of frame 12, to permit S the connector 24 to be withdrawn from its retaining aperture 22, when required.

As best shown for example in Figuie 9, the projections 72, 74, 76, 78 are generally rectangular a ,o in cross section, but arranged so that lengthwise o 0 extending side faces thereof, including side faces 72a, 74a, 76a, 78a on respective projections 72, 74, 76, 78, are inclined 450 relative to parallel upper and lower faces 90 and 92 of the respective body portion 70. There is thus a gap which forms a guide channel 94 between projections 72 and 74 and a further gap which forms a guide channel 96 between the projections 76, 78. The guide channel 74 is defined between surfaces 72a, 74a and guide channel 96 is defined between surfaces 76a, 78a.

Electrically conductive contacts 98 and 100 are positioned within these respective gaps.

having, at an inner end, opposed flanges 104, 106 which extend sidewardly therefrom, but which are deformed out of the plane of the portion 102 so that, with the adjacent portion 102, they define in transverse section the generally C-shaped configuration shown. The free ends of the flanges 104, 106 are adjacent but closely spaced so as to define a gap 108 therebetween. The flanges 104, 106 define an inner contact part 105 of the respective contact 98, 100, the purpose of which part 105 is described later. The portion 102 is bifurcated, having two parallel prongs 102a, 102b between which there is defined a gap 110 open to the outer end of the respective contact, that is the end opposite gflanges 104, 106 The flanges 104, 106 and the adjacent part of the portion 102 are retained within the interior of the main body portion 70 of the respective section *24a or 24b, with the portion 102 extending outwardly therefrom between respective pairs of projections 78, 76 or 74, 72. The median plane of the portion 102 of each contact extends in the direction of the z-axis shown in Figure 9, the median plane also however being arranged at 450 to opposed pairs of faces 72a, 74a or 76a, 78a of the respective projections 72, 74 or 76, 78 between which the contacts extend. The aforementioned guide channels 94, 96, defined by these pairs of faces t ies also extend at 45 to the median planes of the portions 102 of each contact 98, t I no 09 000 0 a 0 os ft 0 004r 0o 0 ft 9 0 0* 6 *r 94 Of 100 and also at 450 to the "horizontal" median plane of connector 240. In order to so retain the contacts, the projections are provided with lengthwise slots 118 (Figure 13) which receive the side edges of the portion 102. In this fashion, contact 98, are retained in the channels 94, 96 at one end of the connector and contacts 100 are retained in the channels 94, 96 at the other end of the connector.

The portions 102 of contacts 98, 100 are arranged in known fashion to permit interconnection with insulated electric conductors, the conductors being inserted between a pair of projections 72, 74 or 76, 78 with the wire extending parallel to the faces 72a, 74a or 76a, 78a when viewed from the end of the connector as in Figure 12, each gap 110 being dimensioned, and the prongs 102a, 102b being so configured, as to cause the prongs to cut into the insulation on the wire and make electrical connection from the respective contact 98 or 100 to the wire as the wire is so pressed into the gap 110. As mentioned, the pairs of projections 72, 74 and 76, 78 define therebetween guiding channels 94, 96 and these facilitate entry of the wire into the associated contacts 98, 100. Also, to facilitate holding of the wire, the opposed faces 72a, 74a or 76a, 78a of projections 72, 74, 76, 78 are provided with clamping ribs 112, which engage the wire insulation at opposite sides. The actual insertion of the wires can, most conveniently, be effected by use of the tool described in Australian patent 547,489.

By virtue of the described manner of fitting

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Crc C it t I I I the two sections 24a, 24b together, the guide channels 94, 96 at one end of the connector 24 extend, when viewed lengthwise of the connector along axis at 900 to the guide channels 94, 96 at the other end. By this arrangement, torsional effects created by the termination of wires at either end of the connector mutually maintained residual torsional forces on each of the terminated conductors, such torsional forces being transmitted along the contacts 98, 100 or along alternative contacts 120 described later.

The manner of interconnection of the two sections 24a, 24b is shown particularly in Figure 14. As previously descr.bed, the two sections 24a, 24b abut at the flanges 80. The main body portions are each apertured at one of the major faces thereof, being provided with apertures 88. Resilient tongue-like detents 91 extend from the portions these having enlarged hook-like end portions which are outwardly directed and which snap-fit, at surfaces 90b, behind transverse latching portions 93 formed on portions 70 adjacent the apertures 88.

Snap-fitting together of sections 24a, 24b is effected by moving the two sections one towards the other so that the portions 90a of the detents 91 enter apertures 88 and are brought into engagement with the transverse latching portions 93 of the two sections 24a, 24b. In this circumstance, inclined outer faces 97 of the portions 90a then engage inclined inwardly directed faces 95 on the portions 93 and, by camming action, resiliently deform the ends of the detents 91 inwardly towards each other C: II C Ie Its I T I 17 until, as the flanges 80 of the two sections are brought together, the portions 90a of the detents 91 are moved past the transverse latching portions 93 to allow the free ends of detents to again, under natural resilience of the detents, move outwardly to latch the portions 90a behind the transverse latching portions 93. In the assembled condition, the sections 24a, 24b are clamped together in that movement of the two sections away from each other is limited by engagement of inwardly stepped surfaces I 90b on the detent portions 90a with the transverse

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latching portion 93 whilst movement of the two sections towards each other is prevented by engagement of the flange 80 of the two sections 24a, 24b.

*to*ro 0 The two sections 24a, 24b can, however, be removed one from the other by suitable inward 'movement of the end portions 90a of the two detents 91 to permit the end portions to clear from the apertures 88, moving under the transverse latching portions 93.

t Prior to assembly of the two sections 24a, 24b, the contacts 98, 100 may be positioned within the sections by sliding these inwardly from openings in the inner ends of the portions 70, so that these pass out through apertures 116 in the opposite end of the respective portion 70, being the end from which the projections 72, 74, 76, 78 extend. As previously described, the portions 102 of the contacts are then positioned between respective pairs of projections 72, 74 or 76, 78. Although the contacts slide in and are maintained in position in the slots 118 extending i E tO 0 oa 0 4 0 0 91 00 00 0 0 6 #0 along faces 72a, 74a, 76a, 78a of the projections, they are prevented from being moved fully outwardly relative thereto by virtue of these slots 118 terminating, as shown in Figure 13, somewhat short of the free ends of the projections.

At inner ends, inward movement of the contacts 98, 100 is prevented by insertion of retaining pieces 115, one to either side of the connector 24. These are inserted into openings adjacent the openings which receive the contacts 98 or 100 of one of the sections 24a, 24b, before the two sections are positioned together, and are then entered into the corresponding openings on the other of the two sections as the two sections are brought together to complete the assembly. Sidewardly directed portions 115a of the retaining pieces 115 are positioned between the inner ends of the pairs of aligned contacts 98, 100 to separate the contacts of each pair.

Figure 16 shows an alternative "connection" contact 120 which may be positioned in a connector 24 instead a pair of disconnection contacts 98, 100 as previously described. The contact 120 is generally configured so as to correspond to two disconnection 98, 100 contacts joined end to end. Thus, each connection contact 120 has oppositely directed planar portions 102 which are slotted in the same fashion as portions 102 of the contacts 98, 100 and has two pairs of flanges 104, 106, each defining a separate inner contact part 105 of the contact 120. At inner ends, however, the two portions 102 are joined by an intermediate portion 122 of the connection contact i Figure 27 is a plan view of a plurality of terminal 19 120. Gaps 108 are formed between the free ends of the flanges 104, 106 in the same fashion as described in relation to the disconnection contacts. When the disconnection contacts 98, 100 are positioned in the connector 24, there is no electrical interconnection provided between each contact 98 and its aligned contact 100 at the opposite end of the connector. On the other hand, when a connection contact 120 is so positioned, the connection contact provides interconnection between electrical connections which are made at either end of the connector 24. A Sol separate contact 120 may replace each pair of contacts 98 or 100 or one may replace a single pair of contacts 98, 100 in the connector 24.

The connector 24 has a central lengthwise extending opening 124 therethrough, this extending, S. on a lengthwise axis 169, through the opposed body portions 70 and opening to outer surfaces thereof at locations between respective pairs of projections 74, e n76. As best shown in Figure 12, the opening 124 is of generally cylindrical configuration but has opposed lengthwise extending side slots, formed in its peripheral surface one slot 126 to either lateral side thereof as viewed in Figure 12, as well as opposed "upper" and "lower" slots 128, also extending lengthwise of the opening. The diameter of the opening 124 is rather greater than that of the spacing between the projections 74, 76 and the opening is extended lengthwise along opposed faces of these prongs by the provision of concave cylindrical surfaces 130, 132 therein, these surfaces also having portions which define continuations of the slots 126. The slots 128, however, break into the outer eei o 1te j v zin as an unaerground cable, extends upwardly into the carrier 14 through the portion 32.

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C L t C t t g V C end surfaces of the portion 70 at locations between the projections 74, 76.

The slots 126 are aligned with gaps 108 between the opposed flanges 104, 106 on the contacts 98, 100 or 120 to permit electrical connections to be made to the contacts for various purposes as next described. More particularly, Figure 17 shows an electrical component, comprising an over-voltage protection unit 129, which may be so interconnected.

The unit 129 is in the form of a generally box-shaped hollow casing 131 which may, for example, be formed of two halves suitably secured together, such as by snap fasteners.

A shaped projection 135 extends from one face of the casing 131 and carries an electrical contact element 134. This element 134 is formed of an elongate strip like element bent to a generally U-shaped configuration when viewed from the side as best shown in Figure 19 and 20, Figure 20 depicting the internal components of the unit 129. The element 134 has an open ended slot 136 at its outer end so as to form, to either side thereof, respective prongs 134a, 134b. The element 134 is somewhat resilient and is capable of gripping therebetween one of the flanges 18, 20 on the mounting frame 12 to provide electrical connection thereto.

I C II I rft I I An over-voltage protection device 140 is provided within the casing 131, this providing two over voltage protection devices 144, 146 arranged, physically in end-to-end relationship. The contact element 134 is connected via a suitable electrical i i L ne legs 40, 4a ana tne fingers 50, 52 to releasably retain the mounting 21 conductor 142 to the junction between the two devices 144, 146.

The ends of the devices 144, 146 which are not coupled to the conductor 142 are connected via separate conductors 148, 150 through terminals 152, 154 of a connector member 151. Member 151 comprises a mounting section 156 and an outwardly extending elongate cylindrical projection 158 which extends therefrom. The mounting section 156 provides a mounting to casing 131, being positioned within a er complimentary opening in the outer wall of the casing 131. When so positioned, the projection 158 extends outwardly from the casing in adjacent parallel relationship to the contact 134, but spaced therefrom.

Opposed elongate fin-like side contact elements 160, 162 are provided extending lengthwise along the projection 158, the elements being retained in slots extending lengthwise along the outer surface and providing connection to the respect the terminals 152, 154. As shown, each contact element extends in like fashion from the surface of the projection 158, thereof. More particularly, each presents a portion 160a, 162a respectively extending from the mounting section 156 to approximately two thirds of the length of the projection 158. Then, there is a cut-out portion 160b, 162b in each respective contact element 160, 162 and, over these cut-out portions, the contact elements do not extend from the surface of the projection 158. Following the cut-out portions, shaping of the pocket 62 and is shown as being 22 there are, adjacent the free end of the projection 158, respective end portions 160c, 162c of the elements 160, 162, which portions again extend from the periphery of the projection 158.

C: C C arr 4 44 *4 44 4 4 44 *r 4 4 6 4 44 44 4 The projection 158 also has, at diametrally opposed locations which are 900 displaced relative to the locations of the elements 160, 162 when the projection 158 is viewed axially of the connector member 151, opposed integrally formed non-conductive fin-like keying projections 180, 182, 184, 186, 188, 190. Projections 180, 182, 184 are spaced apart lengthwise along projection 158 and are positioned at locations approximately over the middle one third of the length of the projection 158. The projections 186, 188 and 190 are similarly positioned and arranged to be diametrically opposite to the locations of the respective projections 180, 182, 184.

When viewed in plan such as Figure 17, the spacing between the axis 166 of the projection 158 and the axis 168 of the element 134 is arranged to correspond to the spacing between the median plane of each of the flanges 18, 20 on the mounting frame 12 and the axis 168 of the opening 124 in a connector 24 when such connector is positioned in an aperture 22 adjacent that particular flange 18, When viewed in cross-section, the projection 158 presents, at for example a location where both elements 160, 162 project from the surface thereof and where a pair of the diametrally opposed projections 180, 186 or 182, 188 or 184, 190 are present, a cross section which is complimentary to w. uij aydin cowaras eacn otner under natural resilience thereof, to assume the 'Ar t t r

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the cross section of the aforedescribed opening 124 in a connector 24. It is thus possible to position the unit 129 on the frame 12 by advancing the unit 129 theretowards so that one of the flanges 18, 20 is entered into the slot 136 in the element 134 and gripped by the element 134, whilst at the same time the projection 158 is entered into the opening 124, the elements 160, 162 being received in the opposed slots 126 of the opening 124, the respective sets of projections 180, 182, 184 and projections 186, 188, 190 being slidably receivable in the respective slots 128.

The thickness of the elements 160, 162 is arranged such that these elements each pass through the gap 108 between the opposed free ends of flanges 104, 106 of the two side by side disconnection contacts 98, 100 or of connection contacts 120 in a connector 24, by engaging and slightly resiliently outwardly deforming the free ends of the flanges 104, 106 away from each other, thus to make electrical contact with inner contact parts 105 of the contacts 98, 100 or 120. The exact arrangement of this contacting may, however, be varied by varying the extent to which the unit 129 is pressed into a connector 24, whereby to similarly vary the extent to which the projection 158 is entered into the opening 124. Figures 24, 25, and 26 show the effect of different extents of such projection with reference to two of the disconnection contacts 98, 100 arranged in line to one side of a connector 24, it being understood that similar interconnection would occur in relation to two disconnection contacts 98, 100 when positioned at the other lateral side of the T1 i; ii In the following description, like parts of sections

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24 connector 24. More particularly, Figure 26 shows a condition of least extensive such projection. Here, the cut-out portion 160b of element 160 is positioned adjacent flanges 104, 106 of a "front" disconnection contact 98 (being the contact at the end of the connector 24 into which the projection 158 has been inserted) whilst portion 160c is forced into the gap between the free ends of flanges 104, 106 of a "rear-most" disconnection contact 100, to make contact with that contact. Thus, in this condition, one of the two over-voltage protection devices 144, ,146 is connected across the disconnection contact 100 and earth the frame 12) whilst no corresponding connection is made from the disconnection contact 98 dthrough the other of the devices 144, 146.

In Figure 25, a condition is shown at which, Z on further inward movement of the projection 158, cut-out portion 160b is positioned adjacent the flanges 104, 106 of the rear disconnection contact 100 whilst portion 160a makes contact with the front disconnection contact 98. In this way, then, the other of the two devices 144, 146 is coupled to the disconnection contact 98 to earth, whilst no corresponding connection is made to the disconnection contact 100.

Finally, when the projection 158 is pressed i fully inwardly of the connector 24, the rather longer portion 160a makes contact with beth disconnection contacts 98, 100 so that both devices 144, 146 are coupled from the disconnection contacts 98, 100 to earth.

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The projections 180, 182, 184, 186, 188 and 190, are used for indexing the abovedescribed three positions under cooperation with a detent (not shown) .within the connector 24.

The described arrangement permits assembly of a number of terminal units 10 in circular arrangement in a cross connection unit as shown in Figure 27. In this arrangement, "rear" faces of the frames 12 are arranged to face inwardly, with the flanges 18, 20 being outwardly directed. The connections from an exchange via the aforedescribed cable pairs 42 may be made to the rear faces of the frames 12, particularly to the ends of connectors 24 which project inwardly through the frames 12, when mounted thereon. Then, jumper leads may be provided between contacts 98, 100 or 120 of connectors 24 at the "outer" faces of the frames 12. As shown in Figure 1, U-shaped retaining members 170, 172 and an upright support 174 may be provided to assist in retaining wires used to effect the above interconnections.

The described arrangement permits the frames 12 to be decoupled from the frame carriers 14 at the lower ends thereof to enable them to be leaned outwards by pivoting these generally about the lower ends thereof to enable access to be readily obtained to the sides of the connectors 24 positioned at the inner faces of the frames 12.

In an alternative embodiment, not illustrated, the frames 12 are pivotally interconnected at lower ends to the frame carriers 14.

I 26 bThe described arrangement has been advanced maybemade thereto without departing from the spirit adscope of the invention as defined in the appended 4o 004.

Claims (9)

1. :r it E+ IT U i I 41th t IC i tr *l I 27 THE CLAIMS DEFINING THE INVENTION ARE AS FOLLOWS: 1. A terminal unit comprising an elongate mounting frame demountably affixed at one end to a frame carrier, the mounting frame carrying, at two opposite sides thereof, electrical contact portions to permit electrical connections to be made to either side of the frame, the frame carrier being mountable in a condition whereby the mounting frame extends upwardly therefrom to receive electrical conductors which extend upwardly to the electrical contact in a 1ufnier- facdtrarmeby portions on the frame, the frame being pivotal,Aundie flexure of said conductors, and adjacent the frame carrier, by demounting of the frame from the frame carrier whereby, by such pivoting, access from a location at one said side of the terminal unit may be had to electrical connections made to a said contact portion at a remote said side of the frame.

2. A terminal unit as claimed in claim 1 wherein sidewardly positioned retaining structures are provided on said frame carrier to demountably receive the frame, the frame having downwardly depending legs which have apertures, and said retaining structures including resilient tongues, the tongues being receivable into said apertures by movement of the frame to cause resilient deformation of the tongues, until latching conditions are reached at which abutments on the resilient tongues hold the frame in position on the frame carrier,

3. A terminal unit as clkimed in claim 2 wherein said retaining structures include pockets, By virtue of the described manner of fitting I of the frame to enter. aid tongues into said apertures, are entere dsaid pockets in the retaining structures to locate the frame relative to the frame carrier. I tc~ r L *i r I I t I I~ w IV r( S I. I

4. A terminal unit as claimed in claim 3 wherein said frame is of channel-like configuration having a cental web portion and opposed flanges, said legs being formed to either side of a cut-out at one end of the frame, the legs including portions o4 said web portion of the frame positioned to eitherf -44iof said cut-out and in which said apertures are formed.

A terminal unit as claimed in claim 4 wherein, at opposed inner edges of said legs, the web portion is deformed out of the plane of the remainder thereof to form said fingers, said fingers extending generally parallel to said flanges but at the opposite side of the web portion to that at which the flanges are positioned.

6. A terminal unit as claimed in any preceding claim wherein said contact portions are mounted on connectors which are removably positioned in mounting apertures in the web portion of said mounting frame, the mounting apertures being located in rows extending lengthwise of the mounting frame, one row adjacent each said flange.

7. A terminal unit as claimed in claim 6 wherein said electrical contact portions are of a kind permitting conductors to be connected thereto by engagement of the contacts by pressing these into I I t V. ~1 -29 gaps in the contacts, to be engaged by opposed prongs to either side of the respective contact whereby to hold and engage the conductor.

8. A terminal unit as claimed in claim 6 or claim 7 wherein at least one said electrical connector includes, at. the side of the frame to which said flanges extend, an opening whereby an electrical component may be coupled thereto, to make electrical connection with a said.contact portion of that connector, by use of an electrical device having a projection extending therefrom and an electrical contact element on the projection, the projection being insertable into the opening to make the electrical connection, the adjacent said flange of said frame being positioned relative to said at least one connector whereby to permit, at the same time, a i: further electrical connection to be made by engagement of that flange with a contact carried by the electrical device. I I

9. A terminal unit substantially as hereinbefore described with reference to the "I accompanying drawings. DATED this 28th day of November, 1990 t t t C 20 KRONE AKTIENGESELLSCHAFT by its Patent Attorneys SDAVIES COLLISON St t C 9011 i28dd 9,7379AM <24r o