DE7512616U - - Google Patents

Description

Patent attorneys ^{; ::} ·· '':: D 59 victories

DIPL-ING. ERICH SCHUBERT Marburger Tor 2 P.O. Box 46 *

DIPL.- ING. ROLF PÜRCKHAUER ^{Telephone: 10271) 54070}

Telegram address: Patschub, Siegen

75 022 kü / s ^ 8 APR. 1975

British Insulated Callender's Cables Limited, 21 Bloomebury Street, London WClB 3QN, England and

Pyrotenax Limited, Hedgeley Road, Hebburn-on-Tyne, Tync and We ar, MB31 1XR, Engl and.

This application claims priority from British Patent Application No. is. 1776V7 ¹ + * claimed on April 23, 197 '.

End closure for mineral-insulated electrical multi-conductor cables

The innovation relates to terminations for mineral-insulated electrical multi-conductor cables and in particular to such terminations, in which the sheath of the cable ends in a cup-like socket that is placed on the cable end, and in which the cable conductors (or separate conductors connected to the cable conductors in the socket) by an insulating closure member for the socket protrude. In such cable end pieces, the cup-like socket is covered with resin or some other insulating material "Connection" is filled, and usually insulating sleeves are placed on the individual conductors protruding from the socket.

The innovation is based on the task of. End closure the aforementioned genera «5 with regard to the resistance to collapse ar is the free surface of the insulating closure component to improve, and preferred embodiments of the innovation Terminations meet the requirements for protection type "e" (increased safety) in explosive gas atmospheres, as in the individual is specified in "Recommendation 79 of .the International Electrotechnical Commission (IEC) "(1st edition, 1969) and / or in the specification BS 4683: 1973 Part 1 of the British Standards Institution (BSI) and / or through the specification of the Association of German Electrical Engineers (VDE) 0171 / 2.61.

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According to the innovation, the closure component consists of a ceramic or glass insulation; dterial (whereby the ceramic Insulating material is preferred), and its exposed surface is designed so that between the recesses, through which the conductors pass through, a surface flashover distance is formed which is substantially greater than (preferably at least twice as large as) the direct distance between the recesses iiit.

Preferably, the closure member is provided with one or more slots in its exposed surface which extend extend between the or each pair of recesses, for example with a simple diametrical slot in the case of one 2-conductor cable or with a Y-shaped or X-shaped arrangement of slots for 3-j or. 4-wire cable. Various alternative forms could be used, for example, annular grooves, slots and / or ribs surrounding the individual conductors. Around To meet the standards mentioned, the width and depth of each slot should be as well. Height and width of each rib, respectively at least 3 now ".

The cup-shaped socket itself can be of any of the usual types, being attached to the cable jacket, for example can be fastened by clamping or screwing. Preferably it is filled with a synthetic adhesive resin (e.g. with the epoxy resin available under the name "Araldite"), In this case, insulating sleeves on the individual conductors are preferably embedded in the resinous filler material at their inner ends will·

The innovation will now be described with reference to the drawing showing them for example, namely show

Fig. 1 is a partially sectioned side view of a sineral insulated 2-wire cable end piece according to the innovation, the

7512616 09/04/75

Αι -'- f

FIGS. 2 and 3 in two views, one at the end piece

used ceramic locking component, while the

Pign. Ί and 5 in the figure 3 corresponding views further Show embodiments for cables with three or four conductors.

When producing the end connection shown in FIGS. 1 to 3, a metal bushing 1 is cut back The end of the cable jacket 2 is attached, for example by screwing it on, and the cable conductors 3, 4 are spread apart within the socket. Insulating sleeves 5 »6 are attached to the ladder, and a cold-curing epoxy resin compound ("Araldite") is prepared and placed in the socket to fill it, as shown at 7. Before the resin bond hardens, is a ceramic locking component 8 over the protruding Ladder threaded and in '.' Layer pressed, excess Resin squeezed out around the ladder can be removed will. After curing, the resin compound seals the end of the cable, forming electrical insulation for the Head in the socket and secures the locking component 8 in its position.

The closure component 8 is more clearly shown in FIGS. 2 and 3 shown. It is generally cylindrical and has a shoulder 9 at one end for localization in the socket and is equipped with through-holes 10, 11 for the conductors, preferably graded or otherwise shaped so that a mechanical lock or form-fitting connection with the Resin is made. The exposed surface 12 of the closure component 8 is provided with a deep groove 13, the dimensions of which are chosen so that there is a surface rollover distance χ between the two holes results, which is approximately two and a half times as large as the direct distance y between the mouths of the two Drilling.

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Figures, ^J 'and 5 show modification forms in which the shape of the groove 13 is adapted to the three or four holes 1Ί for conductors.

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7512616 üt.0ä75

Claims (9)

75 022 Kü / s Ί a. APR. 1975 claims for protection 1. End closure for a mineral-insulated electrical multi-conductor cable, in which the cable jacket ends in a socket which is applied to the cable end, and in which the cable ladder or separate conductor, which are connected in the socket with the cable ladders, by an insulating closure component for the The socket protrudes, the socket being filled with an insulating "connection", characterized in that the closure component (8) consists of ceramic or glass insulating material and that its exposed surface (12) becomes a between the recesses (10,11,1M) through which the conductor (3, extend through ¹ O, lying surface flashover distance <x) is formed that is substantially greater than the direct distance (y) between the recesses (10,11,14). 2. End closure according to claim 1, characterized in that the exposed surface (12) of the closure component (8) with a groove (13) is formed which extends between d ^ m or each Pair of recesses (10,11,14) extends. 3. Termination according to claim 2 on a two-wire cable, characterized in that the groove (13) has a simple diametrical Groove is. M. Termination according to claim 2 on a three-conductor cable, characterized in that the groove (13) is Y-shaped. 5. Termination according to claim 2 on a four-conductor cable, characterized in that the groove (13) is X-shaped. 6. End closure according to claim 1, characterized in that an annular groove and / or an annular rib on the free Surface (12) of the closure component (8) surrounds each individual conductor (3, Ii). 7. End closure according to one of claims 2 to 6, characterized in that that the width and the depth or height of each groove (13) and / or rib are in each case at least 3 mn ". 8. End closure according to one of claims 1 to 7 »thereby characterized in that the surface rollover distance (x) is at least twice bo is as large as the direct distance (y) between the recesses (10,11,111). 9. End closure according to one of claims 1 to 8, characterized in that that insulating sleeves (5,6) on the protruding conductors (3,4) at their inner ends in a connection mass synthetic resin (7) filling the socket (1) is embedded. 751? P16 08/04/75