US1841572A

US1841572A - Electrical condenser

Info

Publication number: US1841572A
Application number: US103246A
Authority: US
Inventors: Benjamin J Butler
Original assignee: General Electric Co
Current assignee: General Electric Co
Priority date: 1926-04-20
Filing date: 1926-04-20
Publication date: 1932-01-19
Anticipated expiration: 1949-01-19

Description

Jan. 19, 1932. B. J. BUTLER 1,841,572

ELECTRICAL CONDENS ER Filedpril 20, 1926 3 Sheets-Sheet 1 ELECTRICAL coNDENsER v Suva to z @W www,

Jan. 19, 1932. B J; BUTLER 1,841,572

ELECTRICAL CONDENS ER Filed April 20. 1926 3 Sheets-Sheet C5 M 12g, do.

Patented Jan. 19, 1932 UNITED STATES- .PATENT OFFICE BENJAMIN J'. BUTLER, OF SOMERVILLE, MASSACHUSETTS, ASSIGNOR, BY MESNE AS,-

` BIGNMENTS, TO. GENERAL ELECTRIC COMPANY, A CORPORATION' 0F NEW YORK ELECTRICAL Application lcd April 20,

This invention relates to electrical condensers, more particularly to those adapted l connections;

for high duty, as to potential, amperage and frequency.

The object of the invention is to improve the electrical and mechanical construction of such condensers.

The invention comprises the various features described which alsoV are shown in the drawings, of which Figs. l-4 and 8-9 show one form of the invention, Fig. 1 being a top plan view, partly in section, of a type of condenser in which t e invention has been embodied; Fig. 2 a vertical section taken on the line 2-2 of Fig. 1, looking in the direction of the arrows, and showing the invention; Fig. 3 being a miniature plan view of a gasket used in the condenser of Figs. 1-2; and Fig. 4 being an enlarged fragmentary view, somewhat diagrammatic and illustrating certain fused Figs. 5-7 and 10-11 show another form of the invention, Fig. 5 being a vertical sectional view, Fig. 6 being a miniature plan view of a gasket used in this form, and Fig. 7 being an enlarged fragmentary View relative to Fig. 5, somewhat diagrammatic and illustrating certain fused connections;

Fig. 8 is a plan view of the high potential connector of the -condenser of Figs. 1-4; Fig. 9 being a side elevation of Fig. 8, partly in section; and

Figs. 10 and 11 are a plan and side elevation respectively of the modified form of connector of the condenser of Figs. 5-7.

The form shown in Figs. 1-4 and 8-9 comprises a plurality of stacks 12, a metal enclosing casing 1, and electrical and thermal leads connecting the stacks with the condenser terminals. The invention relates most particularly to the terminal leads.

Metal casing 1 is one terminal and the upper portion of member 5 with screws S3 constitute the other terminal. Casing' 1 preferably is an aluminum die-casting;

Member 5 is of metal, and is shown in detail in Figs. 8-9 and in assembly most clearly in Fig; 2. Its lower end is abutted by the inner ends of all the multiplicity of stacks.

CONDENSER 1926. Serial No. 103,246.

The leads to both terminals are adapted for efficiency in the conductivity of both ele'ctricity and heat. -

Leads

4 and 13 are desir` able particularly when the condenser is to be sub'ijected to service at 15 am eres or more; gas ret 4 not being necessary or low current service. Lead 5 is admirably adapted for all service whetherat high or low current but particularlyfor high current service.

The con-densers shown are adapted for high potential duty, each stack comprising a plurality of sections; the sections being separated from one another at their faces by insulating (mica) plates, Figs. 2 and 4, but the foil-armatures of each section bein fused (soldered) to those of adjacent sections, so that all the sections are connected in series to permit high potential difference across the ends of the stack. Thetotal stacked elements are divided into the four short stacks 12 shown, in order to reduce the heat-path byV splitting the total path into four short paths. Some of the heat generated in the stack is dissipated in this Way by conduction lengthwise of the stacks by' conduction via the foil and mica stack sheets to the ends of the stack and thence by metallic conduction to surfaces exposed to air outside casing 1. The rest of the heat generated is conducted by the insulating embedment E (as paraiiin Wax), from the edges of the stack sheets to metal casing 1; but at best this general type of condenser (with insulation-embedded stacks of serially-connected sections) is not an efficient heat-dissipator because the only metal heat path from the individual sections is via their serial electrical connection which.

- and proj ecting The division of the stacked elements in Figs. 1-2 into four separate stacks 12 results in splitting them into four parts which thermally as well as electrically are in parallel with one another; and it increases the number of surfaces of metal heat-conductors which are in face contact with the 'stacked elements, two of such surfaces (see below) being provided for each of the four divided stacks 12. One set of these conductors is constituted of the compression members 2 and screws S1 which conduct to metal casing 1 such heat as can be transferred from the faces ofthe outer stack ends to members 2. The faces of the other ends of the short stacks are in thermal contact with fourlat lateral faces of the lower or wide portions of paddleshaped metal casting 5 of Figs. 2, 8, and 9, so that all the heat which can be transferred from the inner ends of the stacks is conducted via the narrow portion of paddle 5 to the outside of casing 1, said narrow portion extending laterally beyond the stacks out thru the top opening in casing 1, and t ru pyrex glass cover 8 to metal corona shield 10 of large area eX osed to air whence the heat is dissipated. ut in addition other portions of the heat generated inside the stacks by high current are conducted away and dissipated efficiently via the eight electrical connections (see below) to casing 1 and paddle 5. First, as to the four parallel l leads 13 from the outer ends of the stacks to casing 1, these are such that when combined with the arrangement of paddle r5 to be described, they will so increase the heat-removal from the stack as to permit this type of condenser to be operated at upwards of 15 amperes at a practically low stack-temperature. These four parallel connections comprise four wide thin flexible copper 4strips 13, one of which is shown in plan in Fig. 1 and two of which are shown in edge view in Fig. 2; and these four strips are connected between casu ing 1 and the four stacks 12. For this purpose use is made of the clamping action of bottom metal cover B, Fig. 2, for the bottom opening of casing 1 which is large enough to permit entrance of stacks 12 and paddle 5, and thru which (while casing 1 is inverted) the molten insulating filler is poured after the stacks and paddle are clamped by the side walls of the casing. In order to make use of such clamping action of cover B, a gasket 4 (Fig. 3) of thin copper is stamped to the configuration of the outer` surface of the bottom edge of casing 1 around the edge of the bottom filling opening, holes being formed for the clamping screws S2 (Fig. 2), and inwardly projectingl integral tabs T being provided which (Fig. 2) project inside the casing. Before embedding filler E is poured in, the four copper strips 13 are fused (as by soldering F, Fig. 4) to the four tabs T,

' of gasket 4, the other ends of strips 13 being remera.

similarly fused tothe armature foils of the outer sections of the four stacks as shown at F, Fig'. 4. While the heat conduction from say the middle of each stack via the serial connection of the section foils to the projecting foil bunch of the outer section is not very great, yet for such heat as lis so conducted, the above leads' are ample for conduction to casing 1, for the above construction is such that the heat path is continuously metallic without separating joints, from the foils of the outer section to metal gasket 4, and the thermal contact of the both sides of the gasket with metal casing 1 and metal cover B is made very broad (altho the gasket itself is narrow) by the use of member 4 in the form of a gasket extending entirely around the rim of the bottom opening, so that the total area of the thermal gasket member is of the same order as that of the surface contacts between tabs T and strips 13; and furthermore the thermal contact of gasket 4 and casing 1 is greatly improved by the clamping action of bottom cover B which is applied, with screws S2, after casing 1 has been filled with waX-E andthe filler has frozen and the entire condenser re-inverted to normal upright position. The soft metal of heat conducting member 4 (as copper) permits its action as a true gasket between casing 1 and bottom cover B.

On the other (inner) ends of the stacks is paddle 5. Tothe lower end or wide portion of the paddleare fused the bunches of armature foils which project from the four sections which abut the four faces of the paddle (Fig. 4 at F) so that (in addition to the good thermal contact between the end faces of the stacks and metal '

members

2 and 5 clamped thereto by the casing walls) there is continuous metallic conductivity, without any separating joints, between the high potential ends of the armature system of each of the four stacks a-nd themetal of paddle 5. And in order to permit the paddle to conduct away rapidly all such heat as may be transferred to it from the four end clamped surfaces and from the four armature systems, the metal in it (Fig. 9) is made continuous andwithout separating joints, as b a single casting and a cross-sectional area o adequate dimensions extending from its lower end or wide portion in clamped relation to the stackends, to its upper end which is in clamping relation with corona shield 10 as a heat-dissipator to air. As shown in Figs. 8-9 the wide portion of the paddle is adapted to rovide surfaces of sufficient area to cover the c amped stack-ends, said wide portion being made metallically continuous with the narrow upper portion (which is preferably cylindrical) by a curvature of the casting providing adequate mechanical strength. 4 The narrow portion is formed with a shoulder L (Fig. 9)v to form a yet narrower portion receiving metal washers S4 and 6, terminal screws S3 (Fig. 2) and also yielding glass bowl cover 8; and at narrowest portion is threaded at H (Fig. 9) to receive said mal), the one, 13, extending from the outer ends of each armature system to metal gasket 4 clamped to heat-dissipating casing 1, and the other, 5, extending from the inner ends of each armature system to the metal washer 6 clamped to heat-dissipating bell 10; this construction possessing all the advantages zo above pointed out.

In Fig. 2 the material S7 shown between the threaded narrow portion of paddle 5 and the wall of the opening thru glass bowl 8 is ordinary adhesive tape used as a buffer between 5A and 8 to prevent the former from chipping the latter. Pyrex bowl 8 is secured to casing 1 by cement in the groove shown in the `casing-rim around the top casingopening.

As shown in Figs. 9 and 2, the wide portion of paddle 5 is hollow and the narrow portion or paddle handle is solid, the crosssectional area of each being substantially the same, for heat conduction; and the bottom of the hollow wide portion of the paddle is open toward the bottom filling'opening so that the molten filler readily can fill up the hollow of the paddle which is a high potential part.

Figs. 5-7 and 10-11 show modified forms of the leads above described. The stack system consists of onl one pair of stacks instead of the two palrs, four in all, in the socalled clover-leaf form of Figs. -1-4. Hence the wide portion of paddle 5 is wide in area but not in thickness and is solid instead of i hollow as in the cubical form of Figs. 1-2; but it possesses all the other characteristics of the form of Figs. 1-2 including the metallically continuous and adequate cross-sectional dimensions suitable for conducting away all heat supplied to it without any in-v terruption as by a joint causing discontinuity of conduction. The rate of conduction of heat thru any system is so very slow that the construction of this paddle in any form is very advantageous. 4

The shape of the metal casing of Fig. 5 is conformed to the single pair of stacks, and themetal gasket 4 of Fig. 6 is conformed to the shape of that casing. The casing here has no bottom opening, and a metal cover B is interposed between casing 1 and pyrex cover 8, the cover B being formed with the groove in which cover 8 is secured by cement C. In this form the molten filler E is poured into the casing thru the top opening, as into gaskets 9 against Aa temporary mold in which a portion El of wax is cast around the narrow p ortion of paddle 5 to approximately the top of glass cover B. In this arrangement (the mode of y assembly of which differs from that of Figs.

1-2), the metal gasket is laid on the top rim of casing 1; but as in Fig. 2 the flexible copper strips 13 are fused (F, Fig. 7 to the outer foil bunches of each stack and also to the integral tabs T, on gasket 4.

The advantages of the invention have been stated above.

I particularly point out and distinctly claim the part, improvement, or combination which I claim as my-invention discovery, as follows 1. A high duty electrical condenser of the insulation-embedded type, which comprises la pair of series-sectional stacks having foil armatures; a paddle-shaped metal casting located between adjacent inner ends of the Y stacks; a metal gasket; and two flexible metal strips; said stacks, paddle and'y strips being enclosed by a metal casing having a large opening for insertion of the stacks and having a smaller opening closed by an insulating cover, the narrow portion of the paddle prov jecting outside the casing thru the insulating cover and supported by said cover; the stacks and the intervening wide portion of the metal paddle being clamped together by means of the metal casing walls, and the intervening wide portion of the metal paddle being fused with the foil armatures of sections yof the stacks adjacent it; the ends of the flexible Vstri s being fused respectively to the metal gas et and to. the foils of the outer stacksections nearer the casing walls; and the metal gasket being clamped to the metal casing around the -large opening therein by means of the metal cover for'said opening, the metal casing containing an insulating embedment.

2. A high duty electrical condenser which comprises a pair of series-sectional stacks; a paddle-shaped metal casting located between adjacent inner ends of the stacks; a metal gasket; and twoiexible metal strips; said i stacks, paddle and strips being enclosed by a metal casing having openings in opposite walls, an insulating cover for one opening and a metal cover for the other opening; the narrow portion of the paddle projecting out thru the insulating cover and supported thereby, and the wide portion of the paddle extending over the adjacent faces of end sections of the stacks and fused with-the armatures of said sections; the ends of tle fiexible metal strips being fused respectively to the metal gasket and to the armatures of the outer sections of the'stacks; and the metal gasket being clamped to the metal casing by the` metal casing cover.

3. In an electrical condenser of the type having as one terminal a metal casing enclosing the condenser elements and having an opening closed by a cover, the means connecting the casing and condenser elements which 5 comprises a metal gasket shaped to the conguration of the outside of the casing at its opening adapting it to be clamped to the metal of the casing by the cover for the opening; said gasket having inwardly projecting tabs adapting it for electrical connection with the enclosed condenser armatures.

4. In an electrical condenser of the type having as one terminal a metal casing enclosing the condenser elements and having an opening closed by a cover7 the means connecting the casing and condenser elements which comprises a metal gasket shaped to the configuration of the outside of the casing at its opening'andV clamped to the metal of the casing by the casing-cover;' and a flexible metal strip fused to said gasket and to the condenser armatures.

5. A high duty electrical condenser coinprising a plurality of series-sectional stacks having adjacent ends electrically connected together; a metal casing enclosing the stacks and having an opening provided With a clamping cover; a metal gasket clamped in electrical connection With the casing by said cover; and a plurality of flexible metal strips each fused at one end to said metal gasket, the other ends of the strips being electrically connected With the outer sections of the stacks 'which lie nearer the metal casing.

6. ln an electrical condenser of the type having as one terminal a metal casing enclosing stacked condenserelements and having an opening and a cover therefor, the terminal leads comprising a metal 'gasket a0 clamped to the metal casing by said cover, and electrically connected as the condenser lead of one polarity; and a paddle-shaped metal casting having its Wide portion formed with a flat face engaged by the stacked condenser elements and having its narrow portion extending laterally beyond said elements as the condenser lead of opposite polarity.

ln testimony whereof.2 l hereunto alix my signature.

BENJAMIN .i nnriirin.