US1490419A - Eugene d - Google Patents

Description

E. D. EBY

April 15 I924.

BUSHING Filed May 5,

u m g i a n z e 5 Wm fl" a u E Patented Apr. 15, 1924.

UNITED STATES PATENT OFFICE.

EUGENE D. EBY, OF PITTSFIELD, MASSACHUSETTS, ASSIGNOB. T0 GENERAL ELECTRIC COMPANY, A CORPORATION OF NEW YORK.

Application filed May 5, 1919.

To all whom it may concern:

Be it known that I, EUGENE D. EBY, a citizen of the United States, residin at Pittsfield, in the county of Berkshire. tate of Massachusetts, have invented certain new and useful Improvements in Bushings, of which the following is a specification.

My invention relates to bushings ada ted to house the leading-in connections or encased electrical apparatus, and has for an object an improved construction which is durable, weather roof, and economical.

More specific-a1 ymy invention relates to bushings for currenttransformers and current metering devices which have their windings arran ed in a plurality of sections; and is designe to'provide not'only a safe insu lating structure but to provide'convenient means for changingthe connections to the winding sections in a safe and economical manner. 4

In bushings for use on current transformers in service with hi h potential conductors, it is necessary to insu ate the incoming leads from the line from and, although little insulation is require between leads themselves in the-bushing, since their relative'differencefof potential is small." Also where the current transformer isfof standard construction it' is necessary "generally to provide suitable means for changing theratio of transformation Thischan'ge in the ratio of transformationfis conveniently eil'ec ted by changing the connections to the primary u which is usually made in two or more sections such change in connections generally comprises a change from series tomultiple connection or vice versa. 1 v

Heretofore it has been customary to bring a plurality of leads out from the windings to the exterior of the bushing where the desired connections were made.

This ractice however is accompanied by the to lem of making the joint in the connections proof against the weather and also proof electrically against grounds, etc. and when once made is often changed only with difiiculty.

In the practice of my invention, such changes may be readily efi'ected and the connections are always protected when in service in a safe and weather-proof manner because I provide the bushing structure with a housingfor the lead terminals, which is an integral part of the bushing. This hous- BUSHING.

Serial No. 294,831.

all the parts.

For a more complete understanding of the nature and objects of invention, reference should be had to the following detailed description of my invention as applied to the construction of bushings when taken in connection with the accompanying drawing in which:

Fig; I shows a bushing partly in elevation and partly in section'constructed' to embody 'my invention. Figs. 2 and 3 show plan views of the various. electrical connections afiordedby the use of my invention, 4 is a fragmentary sectional view showing certaindetails of my invention, and Fig. .5 showsindiagrammatic fashion the general scheme of connections for sections of a primary winding served by my improved bush ng.

{material The pendent member is supported from the top of the bushing structure through the tube whichengages with an interior portion of thecap 13.

Instead of directly fasteningthe ring 12 to the tank'of the current transformer or other apparatus served by the bushing, an auxiliary ring or collar 14 is preferably employed. since a wider range of adaptability is thus procured, to which collar the ring 12 is bolted or otherwise secured, the collar 14 in turn being secured to the apparatus casing (not shown).

To avoid, and hence to protect against, a difference of potential across various points on the interior of the casing in the space above the surface of the liquid cooling and insulating medium,- shown at s, I provide a conducting shield 17, supported on the surface of the pendent member, the shield being constructed with rolled ends and provided with the conducting spinning 18 which has a ground connection shown at 18' (see Fig. 4) made substantially as explained in U. S. Letters Patent No. 1,304,283 issued in my name May 20, 1919. The spinning 18 thus provides a convenient closure for the lower end of member 11 and will also serve as a support for any insulating filling which it may be desired to place therein. To insure a weather tight joint between the ring 12 and collar 14, one or more gaskets, such as shown at g and g are inserted. Where the spinning 18 has a special grounding connection, as shown at 18, the gaskets will with advantage be made to embrace the projecting rim or collar portion of the spinning, one on each side as shown in Fig. 4.

Four leads 20 are brou ht out from the sections of primary winding,- here shown as two in number and denoted w and 'w in Fig. 5, for the a paratus'served and are brought up throng the tube 15 into the cap 13 and are there secured to suitable terminals (2, b, a and d mounted on a terminal board 21. The leads 22 to the aerial connections pass out through suitable outlets or pockets 23 formed in the cap 13. A separate pocket for each lead 22 is here shown, though obviously a single pocket would do.

To support the terminal board in place and also to impose a definite potential upon a stop 26 is provided in the upper end of the tube 15. This stop consists of one or more discs of insulating-material perforated to accommodate the four leads 20.- To fix this stop 26 in a definite posi- 'tion with respect to the leads 20, a wrapping of cord 27 or other insulating material 1886- cu'red on the leads 20 which wrapping prevents thestop 26 from-passing lower on the leads. The ends of the leads 20 which en- 'ter the cap 13 may be reinforced by a further wrapping of insulatin material as shown at 28 and heldis the desired spaced relation by an insulating plug 29.

The cap 13 which thus houses the terminal board 21, is closed by a suitable cover 30 secured thereto in a weather tight manner by means of bolts 31. The cover 30 is also shown as having a threaded recess 32, engaged by astud 33.

bars, shown at 40 and 41 in Fig. 2, are connectcd respectively across terminals a, b, and 0, 1. The current then coming in on a lead 22 to the terminal a, while traversing the winding w in flowing to terminal a, thence to d and to the other lead 22. will branch from terminal a to terminal I; and traverse winding w in parallel with winding w coming directly to the other lead 22 by way of terminal (I.

l/Vhen again it is desired to change the ratio of transformation from that given by the multiple arrangement to that given by the series arrangement, the cover 30 having been removed, the series connection is effected by connecting a conducting bar,

shown at 45 in Fig. 3, across the terminals 2), 0. The current then coming in on one lead 22 to terminal a will traverse winding w flowing to terminal 0, and thence through the bar 45 to b to traverse winding in (since it is now in series with winding 40) whence it will flow to the other lead 22 by way of terminal d.

Having now described what isat preseat the best means known to me for carrylog out my invention, I would have it un' derstood that such means are merel illustrative and that I do not mean to be l i thereby to the exact details shown nor in the choice of recognized equivalents except as defined in my claims hereunto appended;

mited hat I claim as new and desire to secure a by Letters Patent of the United States,

tion with an upper hollow insulatin member, of a hollow cap secured to sai mem her and comprising a base portion with side outlets and a removable cover, a tubular member within said insulating member and depending from said cap, a terminal board mounted within said cap, and a plurality of leads extending through said tubular member from said terminal board.

2. In a bushing structure, the combination with an insulating member, of a-pendent tubular member 'projecting from the lower end of the first said member, a main fastening ring secured to said lower end, an auxiliary ring securedto said main fastening ring, a conducting member on the projecting portion of said tubular member provided with a collar projecting between said rings, and means for makings: weather ti ht seal between said rings and said co lar.

3. In a bushin structure the combination with an ins ating member, of a pendent tubular member projecting from the lower end of the first said member, a main fastening ring secured to said lower end, an auxiliary ring secured to said main fastening ring, a conducting sleeve on the projecting portion of said tubular member, a conducting spinning secured to said sleeve and having a rim projecting between said rings, means for making a weather ti ht seal between said rings and said rim, an a ground connection between said spinning 16 and said auxiliary ring.

4. A bushing structure comprising up?! and lower insulating members, a main astening ring on said upper member, an auxiliary ring secured to said main ring, and a conducting member overlyin a portion of the surface of said lower insu ating member havi a collar projecting between said rings, an d weather tight acking means between said collar and said rings.

In witness whereof, I have hereunto set my hand this 2nd da of Ma 1919.

i JUGE E D. EBY.

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