AU643297B2 - Electrical coupling device - Google Patents

Description

kegulation 3.2 A U ST RAL I A(4 1 Patents Act 1952 7~ COMPLETE SPECIFICATION FOR A STANDARD PATENT

(ORIGINAL)

S06 0 g :e Neaile of Asscae rvsoa pplicant:~s) No-.):K0882/9 methodat of pefrmniinon tore/us: i 6 -2- ELECTRICAL COUPLING DEVICE This invention relates to an electrical coupling device.

The invention has particular application as a protection device for use in terminal equipment such as used in a telephone exchange for connecting telephone wires. The protection device may provide over voltage protection to the telephone wires and associated equipment.

In one aspect, the invention provides an electrical coupling device adapted for use with an electrical terminal device, the terminal device having first and second terminals, said coupling device comprising a planar element having, at opposed faces thereof, first and second contact elements respectively, the coupling device being insertable between said first and second terminals of said terminal device whereby respective ones of the contact elements of the coupling device make electrical connection to the respective first and second terminals of said terminal device, said coupling device further including a first electrical component electrically coupled from said first contact element to said second contact element and a second electrical component connected froin the junction of said second contact element and first component to an electrically conductive terminal formed on one of said faces of said planar element, said first and second electrical components being carried by said planar element at locations adjacent one or both of the faces of the planar element and so as not to substantially extend outside the area of the faces, and the contact elements being defined on an array of projections at one edge of said planar element.

In one embodiment of the invention, the first electrical component is a resistor and the second electrical component is a tranzorb or a varistor, such as a metal oxide varistor.

C To 93090g,p:\peattIstrards,2 -3- In a preferred form, said coupling device has a plurality of each of said first and second contact elements, pairs of the first and second contact elements being formed one element to either side of a respective one of a plurality of elongate portions forming parts of said planar element, each said elongate portion being adapted, in use, to be positioned between a respective pair of said first and second terminals which terminals are formed in a common terminal block of said terminal device. Preferably too, the terminal block is formed with a first set of said first and second terminals and a second set thereof each said set being adapted to provide electrical coupling to a respective one of two said coupling devices.

The invention is further described by way of example only with reference to the accompanying drawings in which: Figure 1 is a plan view of a protection device constructed in accordance with the invention; Figure 2 is a circuit diagram of the protection device of Figure 1; 5 Figures 3 and 4 are diagrams illustrating the manner of formation of printed

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20 circuit board tracks on respective opposite sides of a circuit board forming part of the device of Figure 1;

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Figure 5 is a diagram illustrating the arrangement of a gas protector interconnectable with a terminal block; Figure 6 is a circuit diagram illustrating electrical interconnections prevailing in the arrangement of Figure Figure 7 is a diagram like Figure 6 but illustrating a condition where two protection devices in accordance with Figure 1 are additionally interfitted with the terminal block; 910628kzispe.002,Otltcom3 -4- Figure 8 is a circuit diagram like Figure 6, but showing additional components added to that diagram by virtue of the interfitting of the protection devices in the manner shown in Figure 7; Figure 9 is a perspective view of an alternative form of protection device constructed in accordance with the invention; Figure 10 is a perspective view of a protection device and a terminal device with which the protection device is to be used; and Figures 11 is a perspective view of a bank of terminal devices and interconnector protection devices.

•go• soo• o S Referring firstly to Figure 1, the protection device shown therein comprises a printed circuit board 12 having a rectangular portion 12a and ten finger-like elongate board portions 12b arranged in parallel disposition and extending from one edge 12c of portion 12a. The printed circuit board 12 has conductive tracks on either side, the tracks on one side face 15 being shown in Figure 3 and those on the other side face 17 being shown in Figure 4. More particularly, 20 there are ten tracks 14 on side 15, one on each portion 12b of the circuit board. Each track 14 extends along the length of its respective elongate board portion 12b, and thence in somewhat open U-shaped form over the portion 12a of the circuit board 12 to terminate at an end portion 16 about mid-way between edge 12c of the circuit board portion 12a and the opposed edge 12d thereof. The portion 18 of each track 14 which is positioned on a re;pective one of the portions 12b of the circuit board 12 forms, at its end on the portion 12b, an electrical contact element 21.

Adjacent edge 12d of the circuit board portion 12a, but spaced somewhat inwardly from that edge, there is, on face 15, a lengthwise extending conductive track 20. Also on the face 15 of the circuit board, there are ten circular track portions 22 each being immediately to the right hand side of a respective one of the tracks 14, 910628,kxJspe.002,tlceom,4 adjacent the edge 12c of circuit board portion 12a from which the portions 12b extend.

On the opposite face 17 of the circuit board (Figure there are ten conductive tracks 24, one extending along the length of each of the portions 12b of the circuit board and thence a short distance onto the portion 12a. Each track 24 terminates, at the free end of the respective portion 12b, in an electrical contact element 23. Aligned with, but spaced from each track 24 there is a further short track 26 about mid-way between the opposed side edges 12c, 12d of the circuit board portion 12a. There is also a further track portion 28 extending lengthwise along the 10 portion 12a at a location which underlies the track 20 on the face 15 of the circuit board shown in Figure 3.

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Various holes 30 are drilled through the circuit board 12 to enable interconnection of electrical components with various of the tracks thereon.

The electrical components which are fitted to the circuit board 12 comprise ten resistors R1...R10 as shown in Figure 1, and ten metal oxide varistors F1...F10, also shown in Figure 1. Each resistor is connected at one end to a respective track 24 (and 20 to track 22) and at the other end to track 26 and also to the end portion 16 of the respective track 14. Each vaistor is connected from a respective track 26 (and the 0. end portion 16 of the respective track 14) to the two tracks 20, 28. These connections may be effected in any usual way, such as by soldering.

The electric circuit for the device 1 is as shown in Figure 2. Here, the various tracks are identified in the same way as in Figures 3 and 4, The result is that each pair of varistors and resistors F1, R1...F10, R10, is connected in series, with ends of the varistors remote from the interconnections with the respective resistors being connected in common at the tracks 20, 28, and with the end of each resistor remote from its interconnection with its respective varistor connected to a respective track 24 and with the junction between each pair of varistor and resistor being connected to a 910628,kxlpe.002,telcom,5 -6respective track 14. The connections made Nit-ween each pair Fl, R1...F10, R10 of varistors and resistors via tracks 14 and 24 are made to a respective pair of the tracks 14 on 24, ones of which pair are at sides of a single respective one of the portions 12b of the circuit board 12.

A flexible earth conductor 36 (Figure 1) is soldered to tracks 20, 28 thus to make connection to the commonly connected terminals of the varistors F1...F10. This is connected at the end remote from the circuit board 12 to an earth connector 38 incorporating a heat sink 0 Referring now to Figure 5, there are shown therein two pairs of electrical e; terminals 40, 42 which form a single set of terminals. These are incorporated into a 0* a plastic housing of a terminal block of a terminal device, there being in that terminal block a first row of ten terminal pairs 40 and a second parallel row of ten terminal pairs 42. The so-formed electrical terminal device may be of known form, such as used in the telecommunications industry for terminating line pairs and providing electrical connections to equipment or other line pairs via jumper leads. In particular, the arrangement shown in Figure 1 is designed specifically for use with such terminal block in the form of a Siemens "type 71 IDS" device. This 71 IDS device is shown C 20 at 180 in Figurestf This device, and other similar devices have provision for assembly thereto of a gas protector cartridge which, when assembled to the terminal block thereof, provides electrical connection, across each set of terminal pairs 40, 42, of a respective gas protector 46, respective electrodes thereof being connected to ones of the respective terminal pairs 40, 42. A third, earth, terminal is connected from the gas protector to earth, more particularly by virtue of an interconnection made to a common metal frame supporting the devices, this being shown at 48 in Figure The device has a body 182 and at one side a set of lpni (not shown) for receiving the separate board portions 126. Terminals 40a of pairs 40 are visible in Figures*l. ,o 910628,klrspc.02.WZlc .6 -7- Also shown in Figure 5 is a representative pair of cables 52 of a telephone line being shown connected respectively to a terminal 40a of pair 40 and a terminal 42a of pair 42. Also shown are cables 54, 56 of a jumper lead these being applied to make electrical connections to cables 50, 52 respectively. These connections are effected, for cable 50, by connecting cable 54 to a terminal 40b of pair 40 and, for cable 52, by connecting cable 56 to a terminal 42b of pair 42. The pairs of terminals 40b are normally electrically connected one to the other as are the terminals 42a, 42b whereby desired interconnections as mentioned between cable 50 and cable 54 and between cable 52 and cable 56 are so effected. However, the terminals 40a, o 10 are provided in a form whereby the terminal 40b has a resilient portion 58 which I .0 resiliently bears against a part of terminal 40a for the purpose of making the described electrical connection therebetween. Similarly terminal 42b has a resilient portion o which normally resiliently bears against the terminal 42a for the purpose of making o. electrical connection as between terminals 42a, 42b. It is possible thus, however, to slide between a pair of terminals 40a, 40b a portion 12b of a device 10 whereby the tracks 14, 24 to opposite sides thereof make electrical connection to the terminal and to the terminal 40b respectively, via the contact elements 21, 23. In this case too, the direct electrical interconnection between the terminals 40a, 40b is broken by the interposition of the insulating material formed by the circuit board 12. As shown, g.I' 20 similar interconnection may be made to another device 10 inserted between contacts 42a, 42b whereby the latter resiliently bear against the contact elements 21, 23 of that device. Of course, the action of inserting the circuit board of a device 10 between the pair of terminals 40a, 40b simultaneously enables similar interconnection to be made between the device 10 and each of the pairs of contacts 40a, 40b in the aforementioned first row thereof. Similarly each of the contact pairs 42 in the second row thereof may be electrically connected to a second device 10 simultaneously, by insertion of this device.

Figure 6 shows the electrical interconnections as between the gas protector 46 and the cable pair 50, 52 and cable pair 54, 56 in the situation where the devices are not in circuit. In particular, the effect is that the gas protector 46 is connected 910628.kxlspcM002,lelcrom,7 -8between the cables 50, 52 and likewise between the cables 54, 56. Usually, there is in fact one such gas protector connected between each pair of cables 50, 52 and 54, 56.

In the situation shown in Figure 7, however, the result of the breaking of interconnection between the terminals 40a, 40b and between the terminals 42a and 42b, and the resultant connection of those terminals to the tracks 18, 24 of the devices is that the cables 50, 52 and 54, 56 are electrically interconnected in the fashion shown in Figure 8. More particularly, a resistor Ri,. ,RlO of one device, (shown for 41 10 example as the resistor RI in Figure 8) is interposed in series between cables 50, 54 o whilst, likewise, a resistor, shown as R1 again, of the other of the devices 10 is interposed between cables 52, 56 respectively. At the same time, two varistors; (shovni :as F1 in each case) are interconnected to the cables 50, 52, being in series across the cables. The earth connector 36 of each of the devices 10 is, when the devices are in ,use and in position as shown in Figure 7, coupled to the frame 48 by gripping thereof by earth connector 38 so that there is, in addition to the electrical interconnection as above described, an interconnection of the common point of the vai'istors (F1 for 0000 example as shown) to earth, more particularly to the common earth points of the gas protectors 46. This is illustrated in the diagram of Figure 8 by showing an earth 20 connection to the gas protector and to the common point of connection between the varistors Ft shown.

The purpose of providing the gas protector between each contact pair 40, 42 is to provide for over-voltage protection such that when a higher than normal voltage appears across a cable pair 50, 52 the gas protector will be activated to assume a conductive condition by (ionization of ionizable gas contained therein) to provide a connection to ground whereby the high voltage is suppressed. The additional components inserted into the circuits by virtue of interposition of the devices 10 as shown in Figure 7 and 8 have the additional purpose of assisting in this over- voltage protection. More particularly, it is known that the gas protectors 46 may not react quickly enough to prevent high voltages being applied through the lines 50, 52 and 910628kxdsp.002,tlecom.8 -9- 54, 56 for a time period sufficient to nonetheless cause damage to the exchange equipment or to the lines themselves. On the other hand, however, the varistors are able to react more quickly, in that once the varistor voltage is exceeded, these become conductive whereby to provide a conductive path to earth. In this condition, too, there is a resultant voltage across the resistors and this action assists in quick conduction of the gas protectors 46. Thus, the protector devices provide additional circuit components which offer additional protection over that normally obtainable by use of the gas protectors alone.

10 In Figure 11, a stack of the terminal devices 180 is shown with interconnected protection devices 10, coupled to the frame 48 via connectors 38.

The described arrangement is particularly advantageous in that the devices may be directly inserted into the pairs of terminals 40a, 40b, 42a, 42b without additional hard wiring at the terminal blocks.

Figure shows an arrangement for a device 100 similar to the device 10 but designed for use with a different kind of terminal block. Here, the device 100 is designed for incorporation into a terminal block including sixteen terminal pairs such as pairs of terminals 40a, 40b and thus there are sixteen resistors, commonly 20 designated by reference numeral 102, and sixteen varistors, commonly designated by reference numeral 104. Tracks 118 on one side of the circuit board are shown in solid In eNeoti e 124.

S. lines and tracksi24a, -4b, 124 are shown in broken linesk Electrically, however, S. the arrangement shown in Figure is the same as that described in relation to Figures 1 to 8.

A particular advantage is gained by use of the invention by way of only having to plug the devices 10 directly into the terminal devices rather than re-wiring the whole terminal devices as would otherwise be necessary.

The described construction has been advanced merely by way of explanation 91o628kxspc.002.tcjcom.9 10 and many modifications and variations may be made thereto within the scope of the appended claims a Q0 00 Go 910628,kxsPe.OO2,tcIcoomI.O

Claims (5)

1. An electrical coupling device adapted for use with an electrical terminal device, the terminal device having first and second terminals, said coupling device comprising a planai element having, at opposed faces thereof, first and second contact elements respectively, the coupling device being insertable between said first and second terminals of said terminal device whereby respective ones of the contact elements of the coupling device make electrical connection to the respective first and second terminals of said terminal device, said coupling device further including a first electrical component electrically coupled from said first contact element to said second contact element and a second electrical component connected from the junction of said second contact element and first component to an electrically conductive terminal formed on one of said faces of said planar element, said first and second electrical components being carried by said planar element at locations adjacent one or both of the faces of the planar element and so as not to substantially extend outside the area of the faces, and the contact elements being defined on an array of projections at one edge of said planar element.

2. An electrical coupling device as claimed in claim 1 wherein the first electrical component is a resistor.

3. An electrical coupling device as claimed in claim 2 wherein the second electrical i component is a tranzorb. 0*.

4. An electrical coupling device as claimed in claim 2 wherein the second electrical component is a metal oxide varistor or other varistor. a.. An electrical coupling device as claimed in any one of claims 1 to 4 wherein said coupling device has a plurality of each of said first and second contact elements, pairs of the first and second contact elements being formed one element to either side of a respective one of a plurality of elongate portions forming parts of said planar element, 30 each said elongate portion being adapted, in use, to be positioned between a respective S pair of said first and second termi-ols which terminals are formed in a common terminal block of said terminal device. 930908,p:op al,eistra.rU,l11

12- 6. An electrical coupling device as claimed in claim 5 wherein the terminal block is formed with a first set of said first and second terminals and a second set thereof each said set being adapted to provide electrical coupling to a respective one of two said coupling devices. 7. An electrical coupling device substantially as hereinbefore described with reference to the accompanying drawings. 10o -a Dated this 28th day of June, 1991 !N :AT N -AORSTRALAN TELEOP ThONS-€OR'eRATION By its Patent Attorneys R DAVIES COLLISON -a 104 L1 **TO I* 0. Se *0 910628,kxspc.002,telecom,12 13 to Sol aABSTRACT Electrical coupling device particularly a protector for use with electrical 5 contact devices (180) such as used in telephonn, exchanges, having a circuit board (12) with eletrical components including resistors (R1 R10) and varistors (Fl. FlO), the too$$*board having prong-like portions (12b) which engage with contact pairs (40, 42) of the contact device (180) to interconnect the components with the contacts. *0 to 910628jodxspe.002,teccm,13