US1489303A - Transformer - Google Patents

Description

' 1,489,303 R. v. BINGAY April 8 1924.

TRANSFORMER Filed Aug. 11 l Patented Apr. 8, 1924.

UNITED s'rn'rus emmw BQEEHT l2. HINGAY, OF PITTQBZFRGH, TRANSFORMER comm, A

rmnronm 4 A nmion Med u it 1:, mo. Intel to. mm.

1 at? whom it may concern:

it known that 1, Roemrr V. Exxon, e citizen of the United Qtatee, residing at nhnrgh, in the county of Alleghen "and o of Pennsylvania, have invcnte car new and useful Improvements in Trans "iormers, of which the following is a speck liee'tion.

'lhis invention relates to transformers and particularly to transformers cooled by a ventilating finid such as oil.

Although this a. plication dimloeea features of invention 'escribed and claimed in my pending application, Serial No. Oct. 17, 3.91.9, this application is direct ed to disclosures and claims notcontained in said earlier a plication.

The object of this invention is to provide a transformer particularly of the double magnetic circuit or shell tyne core in which the boil windin s are formed to have a large surface expose; to the cooling action of too ventilating iluid, and to transmit this cool? ing eli'eet to the less exposed portions so that o greater current density in the copper condoctors is available without excessive temperature rise.

A. further object of the invention is to maintain the symmetry and strength of the winding and use the most ellicient form of more while thus increasing the cooling offeet.

lo. the embodiment of the invention illustrated in the drawing,

Fig. l is a plan view in horizontal section of an oil cooled transformer;

Fig, 2 is a view of the transformer in clevation;

Fig. 3 in a view on enlarged scale of u portion of Fig.1 and Fig. 4 is a detail view of a portion of the transformer winding.

The transformer shown has a double magnetic circuit or shall ty we rore It with the coil (7 around its central leg and having its ends 0 overhanging the core alumni: side.

a The convolutious of the coil C at ouch end P are wound with continuouscurvature so that each convolution is arch shaped ms viewed in smtion. The coil is made oblong, oval or elliptical in Section or of gcnernl elliptical or oval formand the'core legs as seen in section have a greater depth than width minimizing the overall width of core. The laminations of the core R are in plimes parallel to the 1ine ,a (Fig. 1) and substantinlly at right angles to the major-axis of the Bill tidal section of the coil C. I

e transformer is placed in oil in a tank T and the circulation of the oil upward alon the transformer surfaces and downrmmvnu, M0103 1'0 MUM! CORPORATZOI 01 PII'IIYLVLIIA.

war along the sides of the tank cools the coils and core. The ends a of the coil oven hanging the core are maroon (1 to the currents of oil than are the re atively inaccessible and remoter portions of the coil be tween the core legs and in the structure of this invention these exposed ends act to in crease and distribute the cooling effect of the oil over the entire coil.

The coil C is built up of a series of windings W with their convolutiona insulated from each other, forming vertical elli tical walls or sleeves, separated by vertical oil ducts D between spacing strips S. Toward the ends 0 of the coil these spacing strips S become progressivelythiclcer so that the windings are s need further apart ill, the ends and spre out to give ventilating ducts increasing in size townrd the ends as indicated at 5, 6 and 7 (Fig. 3) and the overall dimension of the coil will increase on each side toward each end as. indicated on the drawing by a b 0 (Figs. 1 and 3). The larger more exposed oil ducts at the ends will greatly augment the cooling effect of the oil on the coil rapidly receiving the heat from the coil conductors and flowing upward across the convolutions of the winl. ings.

The conduolors of the wimlinp; are )IGfernhly of flat or square wires wound side by side, (Fig. 4) each convolution 7 being made up of one wire 9 or a plurality of such wires wound together as :1 unit. The convolutions are insulated from each other. for instance by covering or winding a cord 10 around wires or convolutions, or both, or around ulternate wires OrronvoIutionS, or both, and the entire coil is treated with a, coating of varnish or insulating compound covering! all the coil surfaces.. The wires lying side by side gresent a maximum surface to the cooling unl and are separated therefrom only by the layer of varnish 0r insulating compound so that the cooling fluid is euhstantially in direct contactv with the surfaces of the wires.

With the extended coil ends of this invention a large part of the length of each convolution is thus exposed to increased cooling action and the copper wires being excellent conductors of heat ra idly conduct the heat from their less exposed portions between the core legs to the outer ends of the coil where the larger ducts are located. The symmetry and strength of the winding is maintained, because each convolution is wound in smooth oval form on curves of continuous gradually varying curvature of such large radius that the several convolutions are drawn close together and mutually sustain each other. The core legs may be of any desired section but for best eiliciency are ,reierably deep in proportion to their widti; i. e., narrow in me direction of the plane or the laminations, as shown.

The extended coil ends of this invention also naturally accommodate themselves to a containing tank that is circular insection, the ends of the coils extending into that portion of the tank 0 posite the sides of the cons. The-cooling e ect of the fluid is symmetricall and evenly distributed throughout the ieight of the coils, the ascending currents of oil flowing with increased velocity as they become heated. Each convolution is exposed to the cooling effect in substantially the same manner and different portions of the coil vary but little in temperat-ure, so that the stresses between the parts of the coil due to relative temperature changes between the parts are minimized and the coil parts expand and contract together without relative shifting and do not tend to break apart. Each wire of each convolution of the coil is laid in a continuous curve without abrupt chan e or char corners which would cause t e wire a ready laid to bend or buckle outward away from the other coils and loosen further when the winding on of the next convolution PN8S it in the opposite direction. In the coil of this invention the gradual curvature at all ints permits the wires to be maintained 1n cont-mucus close contact under constant tension with each oonvplution drawn snug against the one within it. All parts of the coil mutually supporteach other, and thus the coil is a unitary self-supporting whole with all parts held strongly and so preventing relative shifting and chafing and breakdown in service.

I claim l. Ina transformer the combination with a shell type core oil a coil on the vertical middle leg thereof oblong shape in section and comprising successive windings with ventilating ducts between them substantially parallel to said leg, the ducts towards the ends of said coil being larger than those nearer the center.

2. In a transformer, the combination with a shell type core of a coil on the middle 1 thereof comprising successive spaced win ifi ings with their ends spaced further apart than their intormeditte rtionsa themby providing enlarged venti sting note between said ends.

3. A coil for a transformer compri successive windings of neral ellipti form in'section symmetr cal around both axes and spread apart in the direction of one axis to provide enlarged ventilating spaces between said windings at the corresponding portions thereof.

4. A coil for a transformer com rising succemive windings of general 01 ipticl form in section symmetrical around both axes and spaced apart in the direction of the major axis to provide enlarged ventilating spaces between said windings at their ends.

5. In a. transformer the combination with a cone leg having one dimension in section longer than the other, of a transformer coil or coils of general elliptical form in section and having high tension and low tension spaced windings wound one within the other along said core and more widely separated at their ends to provide vertical ventilstin ducts through said windings of increase size at said ends.

6. In a. transformer the combination with a core leg having one dimension in section longer than the other, of a. transformer coil of general oval form in section and having concentric high tension and low tension windings along the length of said core is said windings being separated to rovi a vertical ventilating ducts throng said windings, which ducts are of increased size at the ends.

7. "In a transformer the combination with a. core leg having one dimension in section longer than the other, of a. transformer coil of general oval form in section and having concentric high tension and low tension windings alon the length of said core leg, said windings ing spaced to rovide ventilating dutcs through said win ings, which ducts are parallel to said core and of increased size at the ends.

8'. A transformer coil havin a narrow aperture for a narrow core an conductors wound around said aperture in successive layers on continuous curvw of varyin curvature formin the ends of said coi int-o arch shape on com rising concentric high and low tension win lugs and having vertical insulating strips spacing adjacent windings to provide continuous vertical ventilatin ducts throughout the length of the coil, sail ducts being of increased site at the en 5. r

9. In a transformer the combination of a vertical core 1e a plurality of surrounding conductor win ings of bare varnidxed wire, said windings being goncentric around the axis of said vertical cor'e leg, the outer windmg surrounding the inner winding, -and.

having vertical ventilating spaces, the sides 18 of whichare formed b said bare varnished core leg and the outer windings surrounding 10 wire, oil adapted to circulate through said the inner windings and having vertical ven spaces and an enclosing tank. tilatin spaces between successive windings 10. in atransformer the combination of a. the si es of which s ces are formed by 0 vertical core leg, a plurality of surrounding said wire, oil adapte to circulate in the coils composed of windings of bare wire, inventilating spaces in contact with the sev- 16 sulating compound se arating the several eral turns of the wire, and an enclosing tank. turns of each winding, said windings bein concentric in relation to each other and sai ROBERT V. BINGAY.

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