US2380048A - Pothead - Google Patents

Description

J9. ATTORN y 1945' J. s. JAMMER POTHEAD Filed June 11, 1942 q\ 3% MR J E 5 w J m M 1% m 4 L l. m. w Wm M Patented July 10, 1945 POTHEAD Jacob S. Jammer, Montclair, N. J., assignor to Federal Telephone & Radio Corporation, a corporation of Delaware Application June 11, 1942, Serial No. 446,559

=7 Claims. (01. 174-152) This invention relates to a new and improved. pothead for the connection of electrical conductors such as insulated power cables to apparatus such as transformers and the like.

One object of this invention is to provide a pothead which, When assembled, will thoroughly exclude moisture not only from the point of the actual connection with the cable but also will prevent moisture from gaining access to the exposed end of the cable which is connected to the pothead.

Another object of this invention is to provide a pothead which will allow the quick and easy connection or attachment of an insulated cable rising vertically to the vertical wall of a transformer or the like.

Another object of this invention is to provide a pothead which can conveniently be filled with an insulating material in such condition as will allow it to be packed into the pothead, so as to surround the conductors lying therein, which insulating material can afterwards be hardened in place so as to retain the conductors in position and so as to keep out moisture from the pothead.

Yet another purpose of my invention is to provide a device for attaching cables to transformers and the like, including a combination cap for the transformer and housing for the cable end,

these two portions being easily assembled into a i unitary structure and each portion being capable of being filled with an insulating material so as to render the unitary structure substantially completely moisture proof.

Still another purpose of my invention is to provide a type of pothead which shall present a 1:6..1131Gl36 insulating barrier between the top terminal and the bottom terminal at which latter point a connection is made to the cable.

Fig. 1 shows in elevation, partly in cross-section, a pothead of one type used in the prior art;

2 is a face view in elevation of the pothead of Fig. l as used in connecting a vertically rising cable to the side entrance of a transformer;

Fig. 3 is a side view in elevation of the structure of Fig. 2;

Fig. 4 shows a pothead according to this invention, partly in cross-section, applied to the side of a transformer, the pothead being-seen from one side; and

Fig. 5 is a front elevatlonal view of the assembly shown in Fig. 4.

In Fig. 1 is seen a conventional type of potheacl illustrating the relative complexity of such structures. The example shown includes a body if) having a tapered structure ll affording entrance to the cable, a capping plate l2, insulators l3 and specially shaped terminals 14 arranged to 'make connection to the end of the cable conductors within the pothead proper and passing through the insulators so as to afford connection at the upper end to the transformer terminals. In order to fasten together these various parts into a complete assembly, which will be thoroughly sealed against moisture, a number of various gaskets, clamp rings, bolts, etc., are needed, as indicated by the drawing.

In Fig. 2 and Fig. 3 it will be seen that the use of this type pothead mounted on the side of a transformer housing demands the provision of an additional protecting housin l5 which must be fastened to the transformer housing and must completely enclose the upper portion of the pothead in order to prevent the entrance of moisture at this point.

Referring now to Fig. 4 and Fig. 5, the pothead of my invention here shown includes an elbow shaped casing 16 fastened at the upper end to the transformer housing ll by means of a flange 18 preferably formed integrally with member l6 and held to the housing by any suitable fastening means such as bolts 19. The lower end of this casing is likewise provided with a flange 20. Through the interior of this casing there pass conductors 2!, 2!, here shown as two in number but which may, of course, be of any number according to the number of conductors in the cable to be connected. The extremities of conductors 2! pass at each end through insulating tapered terminal portions 22, 22, preferable formed integrally with the insulation filling casing l6, ashere'inafter described.

Casing l6, after assembly with the conductors 2| therein, can be filled with an insulating material l6 such as a monomeric styrene which can afterward be polymerized in situ into a rigid mass which will be bonded to casing l6 and which will at the same time hold conductors 2| so separated from one another that accidental contact therebetween or between conductor and casing shall be impossible. This insulation may protrude at the respective ends, so as to form portions 22, 22.

In order to connect the cable 23 to the pothead, I may provide a cap member 24, including a metallic cylindrical portion 25 provided at the upper end with a flange 26. This cap member may be fastened to member 16 by any suitable means such as bolts 21 and an ancillary cap 26' may be arranged to close the lower end of cylinder 25 and also so as tightly to embrace the outer sheath of cable 23 as well known in the art. Within this cap member the cable ends may be branched out as indicated in the drawin and fastened directly to the projecting ends of conductors 2| which pass through member is by any suitable means, as known in the art. These conductors 2| may be formed either of copper rods or may be of stranded material. The cap member 24 may likewise be filled with a monomeric styrene polymerized in situ so as completely to exclude moisture from the extremity of the cable. This filling is omitted in the drawing for purposes of greater clarity, but after all connections are made, such insulatin filling may then be employed.

What I claim is:

l. A pothead for connecting a vertically ex tending cable to an electrical device provided with a connection point on a vertical wall thereof, including a hollow cap of substantially cylindrical shape, embracing the sheath of said cable at the lower end of the cap and flanged at the upper end, an elbow flanged at both ends, connecting the upper end of said cap to the connection point on said device, conductors extending through said elbow and connecting to said cable at one end and to said electrical device at the other end, and an insulating material of monomeric styrene filling said elbow and projecitng from both ends thereof for a relatively short distance so as to keep said conductors out of contact with one another and with the walls of said elbow, said monomeric styrene being polymerized in situ.

2. A pothead construction for providing a cable end connection at an angle to the cable, comprising a body having a curved passage therein, a separate conductor for each cable conductor, located in the passage and projecting from both ends of the passage in position for electrical connection, the ends of each separate conductor being at an angle to each other and one end being arranged for connection to a cable conductor, solid insulating material surrounding each separate conductor and filling the passage, maintaining each separate conductor in position both within and beyond the passage, and a shield surrounding connections between each separate conductor and a cable conductor, said shield being connected to said body and extending from an end or said passage.

3. A pothead construction as set forth in claim 2 in which the body is provided at its other end with mounting means.

4. A pothead construction as set forth in claim 2 in which the shield comprises a tubular casing detachably connected to the body, forming a substantially closed compartment surrounding each conductor connection and adapted for filling with insulating material.

5. A pothead construction as set forth in claim 2 in which the body is provided adjacent one end of the passage with means for mounting the body on a wall surrounding an opening, said insulating material in the passage projecting beyond the body adjacent to said mounting means in position to support each separate conductor through the opening in spaced insulated position, and mounting means at the other end of the passage for connecting the body and the shield, arranged at an angle to said first mounting means.

6. A pothead construction providing a cable end connection through a wall extending in the same general direction as the cable, comprising a curved tubular elbow, a mounting flange at one end of the elbow adapted for connection to said Wall around an opening therein, a mounting flange at the other end of the elbow, a separate conductor for each cable conductor located within the elbow and projecting from both ends thereof in position for electrical connection, solid insulating material surrounding each conductor and filling the elbow, extending beyond the ends of the elbow and maintaining each conductor in insulated position both within and beyond the elbow, the insulating material projecting into said opening and insulating each conductor from the walls of said opening; and a detachable shield mounted on the second flange and. surrounding each connection between an adjacent end of a conductor and a cable conductor.

7. A pothead construction providing a cable end connection through a wall extended in the same general direction as the cable, comprising a curved tubular elbow, means for mounting one end of the elbow on the wall in register with an opening through the wall, a separate conductor for each cable conductor located within the elbow and projecting from both ends thereof in position for electrical connection directly to the ends of said separate conductor, solid insulating material surrounding each separate conductor, filling the elbow and extending beyond the ends thereof, arranged to maintain each conductor in insulated position Within the elbow and to support the ends of the separate conductor projecting beyond the elbow, said insulating material projecting into said opening and insulating each separate conductor from the walls of said open- JACOB S. JAMMER.

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