US1027404A - Terminal insulator in junction-boxes or the like. - Google Patents

Description

y R., DBIBEL.

' TBBMmAL INSULATOB m JUNCTION BOXES OR THE LIKE. 7 v APPLICATION FILED APR. 29, 1909. 1,027,404, Patented May 28, 1912.

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"W aa male i R. DBIBEL. :TBBHINAL INSULATOR IN JUNCTION BOXES OR THE- LIKE.

APPLICATION FILED APR. 29, 1909.

Patented May 28, 1912.

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-'R.-DEIBBL. 1 TERMINAL INSULATOR IN JUNCTIO XES OR. THE LIKE.

APPLICATION FILED AP 1909. 4 1,027,404, Patented May 28, 1912.

ROBERT DEIBEL, or CHABLOTTENBURG, GERMANY, assxonon T SIEMENS anazsisn ax'rmnensnmsonx M, or BERLIN, ERMANY, A conroaa'rron. v v

I TERMINAL msomroz. m JUNCTION-BOXES onrxm m cs.

-Spectficatton of Lettersratent. t t 38,19 I Application filed a ruae, 1909; sena'1no. 492,a49. l

To all whom it may concern: Be it known that 1, ROBERT DEIBEL, .a subject of the Germiin Emperor, and residingat Charlottenburg, near Berlin, Germany, have invented certain new and useful Iln- .provements in Terminal Insulators in J unc tion-Boxes or the Like, of which the following is a specification.

The subject matter of my invention refers to means for obtaining high surface insulation of the terminal-plates of cable closelybeside one another on a plate or the like.

The terminal-plates or similar meansem'.

ployed heretofore have the defect that the moisture precipitated on the surface of the plates causes shunt-connections? Also the'surface of theplates which generally consists of ebonite" or t-he like is gradu; ally destroyed owing to the separaiioh of sulfur dueto the action of the air'fand;

light, and consequently the resistance'of the 1 insulation is considerably diminished.- "The above mentioned precipitate of moisture is particularly noticeable in the devices placed in cable pits and in the open air, on account of the great differences in temperature which occur. Now it has already been pro posed for overcoming such disadvantages to mclose the junction elements in special receptacles filled with oil'so that they are entirely covered by oil. Such covering, however, has the disadvantage, particularly apparent when used for junctions carrying small currents, that theoil-adhering to the individual junction elements seriously interferes with alterations of connections and particularly with all soldering operations which may be desired later on. In addition such means heretofore employed do'hot suit the requirements of the modern art using small currents; It is also common to are range T junction boxes for power current cables in such manner thatsafety devices, interpolated in the branch, are located above the insulating medium, whereas the aema-in ing principal junction elements are arranged in the latter, so that i this arrange ment were employed for small cun'eht.ap-

paratus the above described defects vwouldexist jushthesame. In addition, these T-' junction boxes are usually-filled with an in- -sulating medium heavier than water, so

that the malntenance of a surface insulation is obviously impossible. Lastly it has also been proposed, for increasing the surface insulation, to coat the terminal-plates or the like .with'varnish, but this plan 13, ofcoursc, entirely abortive as the moisture. even creeps over the film of varnish.

i Now a. primary object of myv invention is to do away with these defects by placing the terminals and bare conducting parts which I shall altogether call hereafter junction'ele1nents1in the airabove the terminal-plateandby' covering the terminal platew th a layer oflight oi l for rassnrrise ,u'nderljan'y circumstances to such portionsl otfthe barejunction elements at which they'fa re to be connected with other elements of the, circuit. Since only." ,oil; .which is .lightr specificall than water fisv employed, -1t is impossible or. moisture to pass ,from a .one connect-ion part to another.

In I the new arrangement theterininalplates. the; plate, consisting preterably of a plast-ie'finsulating material can'jmg the te'r-.

minals or other electrically connectingelenentsfiorms'the bottom or a portiorrof the bottom of a trough-like receptacle, the lat- UNITED S TATES gPATENil OFFICE,

-ing. good surface" insu'lation, provision bei ing-madefthatthe surface: of. the oil cannot let being niade 'of amaterial to whir .i

adheres only veryjslightly, such as sheet iron and the like. Recesses which serve for collecting themoisture which has precipitated through the'oil, are preferably formed by the terminal-plate projecting above the bottom surface of the trough-like receptacle in suchmanner, that 'a channel isfornied around the plate. a The particular materials preferably Iuscd for-the receptacle and tcr minal-platehave the advantage that, firstly by employing for the terminahplate a ma- .terial which can be worked in plastic condition'such as ebonite, a tight fit of the plate to thebox bottom and at th tcrn'iinals or other conducting parts extending through it is obtained, and that, mildly, the oil which protects-the plate from the weatherand the terminals from leakage of electricity is pre' vented-from creeping over the side walls of the receptacle. u v

-. In order that my invention may be clearly understood I willnow describethe same with referenceto the accompanying drawingsin which thi'ee constructional forms are.

in-Fi g. 4.. Fig.4 is a top plan view of the form shown in Fig. 3, and indicates also the general arrangements of thelot-her forms, whereas Fig. 51s a vertical section through another modified form, and Fig. 6 is a ver-- tical section through a closed form provided with overflow devices. Fig. 7 is a vertical section of the form shownin Figs. 3 and 4,

taken on the line rv.r in Fig. 4 and seen from'tl1e left.

' Referring to the drawings, t he modifica- .'t1o shown in Fig. 1 represents a unction,

box, cable sleeve or the like having the side walls I) and the bottom portion 1)., inte al therewith, and within walls b the terminal strands f, which form the junction-elements by whicli'connection is made *ifllrtllg conductors leading away from the bait (as for 5' instanceshownin Fig. 6). The bottom of the box or receptacle-has an'open portion 6 which is covered by a. plate a of insulating material through which the. terminal" or junction elements f pass and-in which they are-suitablyfastened: The opening b i-is in this particular case so large that the only remaining portion of bottom b is merely a rim on which plate a rests with a suitable packing material such asfor instance india 5 rubber or asbestos h'interposed to insure a tight joint, which prevents leaking of the f insulating fluid such as oil through the joint. The'plate a. may be fastened to bottom-b in any suitable manner not shown in the 40 drawings. Between the plate a. and wall b is left a clear space which forms the channel c. The screw 2' serves for draining thewater which in the course of time collects there. When the screw is loosened a little, water will flow through the hole 70 and as soonas oil is seen to flow through the same the screwis ti htened again. In the other constructional: orms a special oil-tight joint in the bottom of the receptacle as in Fig. l

at" his unnecessary.

' In the form shownin Fig. -2'the terminalplate a is pressed into the open bottom portion against or around the; bottom flange b of box d composed of meta-Leach as-cast-iron for example. The channel b'is formed, similarly as in the form shown .in Fig. 1, by "leaving a suitable clear space at the periplh cry of the pla. e. The sloping of the surface of the plate asclcarly shown facilitates any moisture'flowing into-the channel.

In the form shown in Figs. 3 and 4 the box 0 is made of sheet metal'having several openings or perforations in its bottom 7), as

clearly shown, for the passage of conduct'ors f. The plate a of initially plastic in sulating material is pressed against both;

sides of the bottom of the box. Here also. a

' be feared on the under side. For this purpose the. inlet 9 is provided as shown for instance-in Figs. 4 and.7, which leads to the underside of the receptacle bottom, and- Fig. .7 clearly shows how the strands run 5 to their individual laces in plate. a and how they are embeddedin theinsulating material 'a- Moreover this figure 'als'o'shows how' conductors 3 are connected above the oil to strands f. Y

In order to prevent. anyoil from cm'sping through'the ebonite plate along the conductors, the'mate'rial of the plate may be raised" tubularly around the terminals to form V bosses as shown in Fig. 5. The receptacle 5 is then filledwith oil only so far that the ends of thesesmall'tubular bosses a project beyond the levelm o'f' the oil-:and consequently the conductors do not contact at all with the oil, as clearly shown in Fig. 5. a

In order to keep the level of the oil always below a predetermined maximum level special provisions must be. made. If the receptacles are open, as shown in Figs. 1 to 5, the maximum level is determined by. the 105, height of the side wall. If there are several distributionboxes they may preferati y be placed beside one another and so a} ranged that overflowing oil from one receptacle runsinto 'les's filled receptacles. closed vessels anoverflow r (Fig. 6) must be provided at a suitable-height. This simple overflow 1' has, however, the disadvantage that the insulating oil flows away and, should the rise of the level of the oil havebeen caused'by water"flowing in, only water eventually remains in the receptacles. This is. prevented When'one or more communicating tubes 8 are provided, the bottom ends of which are arranged cldse above the bottom of the receptacle, asfclearly shownjin Fig. 6. These tubes are then alw'aysfil-led -with the fluid which collects at the bottom of the receptacle, and only the-oil is' lo'st.

' v which was inthe tubes when they were first 12 5 filled. A siphon-t arranged in like manner acts more certainly and better, said siphon being provided above. the normal level an of the oil with an opening to -in order to interrupt the outflow f oil by admitting 'air when the level is reached. I n'thi s, the maximum and the minithetopof plate a is of particular advantage.

I claim: l v

1. In a junction box, of the character described. the combination of a receptacle having a portion of its bottom formed ofinsulating material hermetically attached to the remainder of the bottom and extending a suitable distance above said remainirg bottom, to produce a channel between the less than that of water,

ducting junction elements secured in and receptacle walls and the material, said receptacle containing oil of specificweight and electrically conextending through said insulating material above the surface of the oil, said elements having the r-junction points located above the surface of the oil.

scribed, the combination of a receptacle,

2. In a junction box, of the character de having a portion of its bottom formed of initially plastic insulating material hermetically attached to the remainder of the bottom and extending asuitable distance above said remaining bottom, to produce. a channel between the rece t-acle walls andthe niaterial, said' receptac e containing oil of specific weight less than that of water, and electrically conducting junction elements secured in and extending through said insulating material above th surface of the oil, said elements having their junction points located above the surface of the oil. I

In a junction box, of the character described the combination of a' rece tacle weight less than cally tom and extending a suitable distance above in and extending having a portion of its bottom formed of initially plastic insulating material hermetically attached to the remainder of the bottom to overlap it above and below and extending asuitable distance above said remaining bottom, to produce a channel between the receptacle walls and the material, said receptacle containing oil .of specific that junction elements secured through said insulating material above the surface of the oil, said elements having their junction points located above the surface of theoil.

4. In a junction box, of the character described, the combination 'of a receptacle having a portion of its bottom formed of initially plastic insulating material hermetiattachcd to the remainder of the botcally conducting raid remaining bottom, to produce a chanthe combination of a of water, and electri-.

nel'between the receptacle walls and the ma:

tcrial, said receptacle containing oil of specific weight less than that of water, and electrically conducting junction elements secured in and extendingthroug aid' insulating'material above the spite of the oil, said'elemcnts having theirjunction points located above the surface of the oil, and means for draining moi'sture from the bot tom of said channel.

5. In adevice of the character described, the combination of a receptacle of suitable material having a bottom formed partly'of a plate of insulating, terial, said plate overlapping the rece bottom above'and below and of'su tacle' cient initially plastic mathickness to protrude into the receptacle and 1 to form with the receptacle walla channel surrounding said plate, said receptacle 0011-.

of water, and electrically conducting junc- 6. In a-device 'of'the character des'cribedf receptacle of suitable material having a bottom formed [partly of a plate of insulating initially plastic inaterial, said plate overlapping therece taclebottom'above and below, and of so cient thickness to protrude into the receptacle to form with the receptacle walla channel S111,- rounding said plate, the upper surface of said plate slanting from the edges, said receptacle containing oil of specific weight less than water, and electrically conducting junction elements fixed in said plate and extending above the surface of the oil.

7 In adevice of the character described,

the combination of a. receptacle of suitable material having a bottom formed partly of a plate of insulating, initially plastic material, said plate overlapping the rece tale bottom above and below and'of s cient thickness to form with the receptacle wall a. channel surrounding the plate, said receptacle containing oil of specific weight less than. that of water, said plate having upward extending bosses surface of the oil, and .an electrically conducting junction element fixed in and extending through each of said bosses.

8. In a device of the character described, the combination of a receptacle of suitable material having a bottom formed partly of a plate of insulating, initially plastic ma-. terial, said plate overlapping the rece bottom above and below and of su cient thickness to form with the receptacle wall a channel surrounding the plate, the upper surface of the plate slanting from its center toward the edges. said receptacle containing oil of specific weight less than that of water,

said plate having upward extending bosses protruding above the surface of the oil, and

protruding above the the center. toward tacle taining oil of specific weight less than that 85 an electrically conducting junction element carried by and extending through said plate above thef'surface 'ofthe oil, and means for preventing the oil from-exceeding the'de- I sired maximum level.

'10. In a device of the character described, the combination of a receptacleof suitable material having a bottom formed partly of a plate of insulating, initially plastic material, said receptacle containing oil ofspecific weight less-than that of water, and electrically conducting junction elements carried by and extending through said plate .above the surface ofthe oil, said receptacle 'having a tube'ior conveying fluid-out of it and into an adjoining receptacle, said tube v extending from the bottom of the receptacle upward slightly above the normal oil level "and gslightly downward again, substantially electrically conducting junction elements as showii i tb prevent the oil from exceeding the desiredmaximum' level.

11. In a device of the character described,

the combination of a receptacle of suitable materlalhaving a bottom formed ,partly of a plate of insulating, initially-plastic ma-f terial', said receptacle containing oil of specific weight less thanthatof water, and

electricallyc'onductingjunction elements carried by and extending through said plate 'abovethe surface of: the oil, and a siphon tube in said receptacle extendingfrom near the bottom -th'ereof tothe height 'of the maximum oil level andout through the wall 0f the receptacle, said siphon tube-having an opening inside -of gthe receptacle at the height ofthe minim am oil level to break the siphon action when the oil level has fallen to theminimum level to prevent the oil from exceeding the desired maximum level.

vIn testimony whereof I have signed my name to this specification in the presence of two witnesses. A

Witnesses: HENRY Hssrninf 4 'wownm

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