US1986842A - Cable terminal - Google Patents

Description

Jan. 8, 1935. F, c, MEYER ET AL 1,986,842

CABLE TERMINAL Filed Sept. 12, 1952 M a z UNITED STATES PATENT OFFICE CABLE TERMINAL Fred 0. Meyer, Paterson, and George E. Moflitt,

East Paterson, N. J., assignors to The Okonite- Callender Cable Company, Incorporated, Paterson, N. J., a corporation of New Jersey Application September 12, 1932, Serial No. 632,753

1 Claim.

This invention relates to an improvement in indoor terminals for cable systems of the pressure type, that is to say, where the insulated unsheathed conductors are drawn into or enclosed in a pipe or sheath filled with oil under pressure such as disclosed, for instance, in the copending application of Charles E. Bennett, Serial No. 553,714, filed July 29, 1931.

The drawing shows an embodiment of the invention in sectional elevation.

Referring to the drawing in detail, 1 and 2 designate, respectively, inner and outer sheaths of lead and 3 an intermediate fabric or other suitable material of such a nature as to permit of expansion of the sheath 1 to provide a space or reservoir between it and the insulation of the conductor which is filled with oil maintained under high pressure. The sheath or pipe structure just described is for illustrative purposes only, inasmuch as other types of cable enclosures may be employed so long as provision is made to maintain a body of insulating liquid under high pressure. in contact with the insulation of the conductor.

Permanently and rigidly secured to the sheath structure of the cable by a wipe joint 4 is a metal sleeve 5. The interior of this sleeve or rather the space between this sleeve and the insulation of the cable conductor is in communication with the interior of the cable sheath or pipe 1. A pipe 7 with which the sleeve 5 is provided is connected to any suitable source of oil under pressure.

Screwed into the upper end of the sleeve 5 is a pressure .tube 8 of suitable insulating material, such as a phenolic condensation product for example, and slightly larger internally than the paper insulated conductor. The interior of this tube as will be apparent from the drawing is at all times in communication with the interior of the cable sheath or pipe so as always to be under high internal pressure.

Supported in the upper end of the sleeve 5 is a metal cone 9 attached to the sleeve or gland 5 by wipe-joint 10. This cone which surrounds the pressure tube 8 supports a series of electrostatic shielding-barrier tubes 11 of insulating material as well as an insulating casing 12. The lower end of this casing is secured to the upper end of the cone 9 by winding a tape 13 about the same, varnish being applied to the tape between adjacent layers. 1

The upper end of the cable conductor, designated 14, is attached by a connector 15 to a braided conductor 16 in effect forming a continuation of the conductor and permitting of longitudinal expansion of the conductor.

Screwed upon the upper end of the pressure tube 8 is a tube 1! equipped with cap plate 18 held in place by bolts 19.

Extending through the cap plate 18 is a thimble or plug 20 having a head 21. This plug 20 is permanently secured to the braid 16, projects upwardly through the cap plate 18 and is drawn thereto by a nut 22. The cap plate 18 is equipped with a vent pipe 23 communicating with the interior of the pressure tube 8 for venting the pressure tube on initial filling of the same.

The top of the casing 12 of the terminal is provided with a cone-shaped cover or top 24 which overlaps the top of the insulating casing at its lower end and surrounds the pressure tube 8 at its upper end. The joint between the cap 24 and the casing 12 is made liquid tight by this application sleeve wiped to the end of the cable casing and constituting a continuation thereof, a pressure tube sealed at its lower end within said sleeve, a cap for the upper end of said pressure tube to seal the same, the cable conductor projecting from the cable casing through said sleeve and into said pressure tube to a point adjacent the upper end thereof, a flexible extension secured to the end of the cable conductor and projecting from the upper end of said pressure tube in a liquid tight manner, a metal conical member extending into said sleeve between it and the pressure tube, a wiped joint for connecting the conical member to the upper end of said sleeve, said conical member flaring outwardly with respect to the sleeve and surrounding the pressure tube and its contained cable conductor, a casing member of insulating material telescoped by said conical member and secured liquid tight thereto, a metal cap telescoping the upper end of said casing member and secured liquid tight thereto, spaced barrier tubes of insulating material concentrically disposed with respect to each other and surrounding said pressure tube, said barrier tubes resting upon and being supported by said conical member, said pressure tube permanently separating the interior of the casing from the interior of the pressure tube, and liquid insulation within said casing external of said pressure tube and under lower pressure than the liquid insulation in the pressure tube and cable casing.

FRED c. MEYER. GEORGE E. MOFFI'I'I'.

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