GB735399A - Improvements relating to the pressure-tight sealing of electric cables into housings - Google Patents

Abstract

735,399. Carrying cables through partitions; mechanical couplings for cable sheathing. TELEGRAPH CONSTRUCTION & MAINTENANCE CO., Ltd. July 1, 1954 [July 9, 1953], No. 19092/53. Classes 36 and 38(1). A sheathed insulated conductor 1 is sealed into the entry 4 of a housing H by means of a metal thimble 6 tapering externally towards each end and having a bore fitting the conductor 1, a pair of inner insulating sleeves 9 tapered internally and externally mating with the tapered portions of the thimble and with tapered internal surfaces of a pair of outer metal sleeves 12 which are a close fit within the entry 4, resilient sealing rings 17, 19 being located between adjacent faces of the thimble, sleeves and entry, and a screw device at one end of the entry imparting endwise thrust to one of the outer sleeves to compress the sealing rings. The sleeve 12 nearer the interior of the casing H has a threaded portion 21 which is screwed into a threaded portion 23 of the entry 4 until a flange 22 abuts against a shoulder formed by counterbore 24. A collar nut 26 bears against the outer end of the other sleeve 12 and is externally threaded to engage in a screw-threaded recess 15<1> in the entry 4. A resilient sealing washer 25 is interposed between adjacent ends of sleeves 9 and 12, and this washer, together with the sealing rings 19 is compressed when the nut 26 is tightened. An axially tapered moulding 28 of insulating material is bonded to the end of conductor insulation 2 and is enclosed within an extension of cable sheath 3. An internallytapered collar 31 is urged into counterbore 30 in entry 4 by a screw-threaded cap 32 engaging with thread 33 on entry 4, to retain the head 29 of moulding 28 in position.