US1542144A - Core of transformers - Google Patents

Description

Y. KATSUMOTO CORE OF TRANSFORMERS June 16, 1925. 1,542,144

Filed Feb. 21. 1922 Patented June 16, 1925.

UNITED STATES YASUTARO KATSUMOTO, 0F NISHI-K-U, OSAKA, JAPAN.

CORE OF TRANSFORMERS.

Application filed February 21, 1922. Serial No. 538,394.

To a]! whom it may concern:

Be it known that I, YAsU'rAno KA'rsUMo'ro, a subject of the Emperor of Japan, residing at No, 36, 'lorishi1nzt-cl1o,' Nishi-ku, Osaka, Japan, have invented new and useful Improvements in a Core of Transformers, of which the following is a specification.

This invention relates to improvements in transformer cores having radially extend ing frames made of sheet iron, and has for its object to provide a transformer having a large cooling surface, while at the same time the quantity of iron and copper used in constructing the core is comparatively small.

in the accompanying drawings a numberof examples of cores constructed in accordance with the present invention are shown, and from which the principle of the invention will be readily understood. In said drawings: 1

Fig. 1, is a perspective view of a trans former provided with a core havingtwelve frames; 7

Fig. 2 is a plan view of the transformer shown in Fig. l; I

Figs. 3 and 4, are plan views of transformers having fifteen and eighteen frames respectively Figs. 5 and 7 are sectional plan views of the assembled inner legs of the frames forming the central pole of the core of the transformers shown in Figs. 9. and 4 respectively Fig. 6 is a sectional plan view illustrating another form of central pole.

The same characters of reference designate the same parts in the different figures of the drawings.

Referring to the drawings, each of the frames comprises an inner vertical leg 0, an outer vertical leg I), and horizontal legs 0 connecting the legs a and b at the upper and lower ends thereof, said legs together forming a tetragonal frame. The outer and connecting legs of the sections of the frame may be of any convenient form, provided they are of the same area, but the inner legs are of rhombic formation.

The frames above described are arranged radially, the inner legs being assembled side by side to form the central pole of the core,

as clearly shown in the drawings. The assembled inner legs may be disposed in a singlelayer, or in two or more layers, according to the number of frames. The sec length of the coils.

tion of the pole thus formed is a regular hexagon. The frames may be so assembled that the inner legs form an opening at the center of the core, as shown in Fig. (3, or if preferred, the center portion may be solid, as shown in If'ig. T. In Figs. 2 and 3, the assembled legs form an opening at the center, but said opening is filled with a sheet iron core 6. The connecting legs (2 may extend straight as shown in Fig. 2, but all, or some of thenrmay be curved along their sides as shown in Figs. 3 and 4, when desired. The connecting legs attached to the inner layer of the central pole are disposed outside of those attached to the outer layer of said pole, but all of the outer vertical legs 6 are distributed at the same distance from the center, that isto say, in a circle.-

Coils (Z are wound on the central pole of the core, as is well known in transformers having radial cores.

In the present invention, a sectional view of the central pole of the core is a regular polygon, and the outer legs are divided into a number of sections distributed almost all over the outer surface of the coils, and the laminations of iron comprising a single unit of the frame are of the same dimensions. Consequently, the mean length of the connecting legs is reduced, and that of the inner legs may also be reduced. Because of this construction the core can be divided into a number of sections so that said core may readily be distributed almost over the entire outer surface of the coils. As a result of this disposition, the thickness of the outer legs may be greatly reduced while keeping the required sectional area, thus effecting a considerable saving in the quantity of iron used in the construction of the transformer.

Furthermore, as the cross section of the assembled inner legs is a regular polygon, the coils may be wound thereon so as to form a circle. so that the mean length of the coilsmay be reduced. This saves a considerable quantity of copper in the total Moreover, the curvature of the coils being less sharp. not only is the operation of winding rendered very easy, but the insulation is not subject to injury by any necessity for sharply bending the wire.

From the foregoing it will be seen that lit) large compared with its volume, which atfords etlective cooling of the tianstornzer thus considerably increasing the etl'iriency ot' the latter, while the weight, as well as the initial cost are materially reduced.

Having thus described my invention, what I claim is:

1. A transformer core, comprising a phlralit ol radially extending sheet iron frames ol uniform dimensions each hav' an inner vertical leg, an outer vertical itand a pair of horizontal legs imniectin 7 ends of said vertical leg," the inner oi the frames being disposed in contiguous relation in at least two layers and forming a central pole, the sectional torn: ol th in ner legs being rhonihic and the outer vertical legs disposed in a circle.

2. A transformer core comprising radiall v extending sheet iron frames of uniform dimensions each having an inner vertical leg, an outer vertical leg, and a pair of horizontal legs connecting the ends of said vertical legs, the inner legs of the frames being disposed in contiguous relation in at least two layers and forming a central pole ot hexagonal section, the sectional form of the inner legs being rhoinhic and the outer vertical legs disposed in a circle.

3. A transformer core, comprising radially extending sheet iron frames 02'' unilorin dimensions, each having an inner vertical leg an outer vertical leg and. a pair of hori zontal legs connecting the ends ol' said acrtical legs. said connecting legs being curred along their sides, the inner legs ol the frames being disposed in contiguous relation in at leasttwo layers and torining a central pole o't hexagonal section, the s tional form of the inner le 's being rhoinhie and the outer vertical disposed in a circle.

In testimony whereof l have signed my name to tl'iis-specification,

YASUTAR KAIS [U l )Tt).

Images