US1433701A - Transformer - Google Patents

Description

G. H. COLE.

TRANSFORMER.

APPLICATION FILED |-ov,2o,192ov Patented Oct. 31, 1922.

INVENTOR 2 Y WW O w y A 8 0 f 8 m G m Patented Oct. 31, 1922.

UNITED STATES GUERNEY H. COLE,

OF WILKINSBURG, PENNSYLVANIA, ASSIGNOR TO WESTINGHOUSE ELECTRIC & MANUFACTURING COMPANY, A CORPORATION OF PENNSYLVANIA.

TRANSFORMER.

Application filed November 20, 1920. Serial No. 425,521.

T 0 all whomv it may concern:

Be it known that I, GUERNEY H. COLE, a citizen of the United States, and a resident of Wilkinsburg, in the county of Allegheny and State of Pennsylvania, have invented a new and useful Improvement in Transformers, of which the following is a specification.

My invention relates to transformers and it has particular relation to coil supports or tongue Wedges therefor.

One of the objects of my invention is to provide a tongue wedge of the character described and constructed of a non-conducting and non-magnetic material that will prevent eddy currents being set up therein by reason of adjacent stray magnetic fluxes and will, therefore, not become excessively heated.

Another object of my invention is to provide a tongue wedge having the characteristics above set forth that may be constructed of a strong material that will resist the stresses occasionally set up within the transformer by reason of short circuits or overloads.

Heretofore, in the designing of transformers, it has been customary to construct the tongue wedges of structural steel, as it has been believed that they were positioned at points where there was practically no magnetic flux. It has. however, been observed that tongue wedges, of such material and so located, become excessively heated, and frequently to a' degree sufiicient to injure the insulation adjacent thereto. This heating has probably resulted from stray magnetic fluxes occasioned by a difference in the reluctances of the adjacent legs of the respective core members.

It is practically impossible, by reason of the dissymmetry of the individual coil members, to so align the respective primary and secondary coil members as to cause the geometrical centers to coincide with the magnetic centers thereof. This has resulted in very powerful stresses being set up in oppo= site directions when a short circuit developed which was resisted almost entirely by the tongue wedges.

These wedges, by reason of the fact that the principal supporting means therefor are located at each end thereof, must be constructed of such material and be so designed as to effectively resist the stresses set up by the repelling action of short circuited coils.

Briefly speaking, my invention consists in vweb portion providinga tongue wedge constructed of a yery strong non-magnetic and non-conductlng material within which it will be impossible for eddy currents to form.

In the accompanying drawings:

Figure 1 is a front elevation of a transformer provided with a tongue wedge constructed in accordance with my invention.

Fig. 2 is a vertical longitudinal sectional view on line IIII of Fig. 1.

Referring to the drawings, a shell-type transformer is shown as comprising a plurality of core members 1 having a plurality of spaced and parallel primary and secondary pan-cake coils 2 and 3 arranged for inductive relation therewith. The core members 1 are preferably supported and bound together by upper and lower longitudinally and laterally extending channel bars 4 and 5, respectively, connected by a plurality of vertically extending tie-bolts 6, in the usual manner.

The coil members 2 and 3 are securely bound together against movement in a direction normal to their faces, by upper and lower pressure plates 7 and spacing blocks 8 connected by longitudinally extending bolts 9. The coils 2' and 3 are directly supported and vertical movement is prevented by upper and lower longitudinally extending tongue wedges 10, preferably of T-shape in crosssection, having a' horizontal portion 11 and a vertical web portion 12.

The tongue wedges 10 are preferably con Structed of a non-magnetic and non-conducting material, such, for example, as a bakelite composition having relatively high tensile strength. The tongue wedges 10 are arranged with the horizontal flanges thereof in engagement with the upper and lower edges of the core members 1 and with the vertical 12 extending between the respective cores. The extremities of each of the wedges 10 are arranged for engagement with the edges of the upper and lower chan nel bars 5 and are maintained in position by vertically extending jack bolts 13. Longitudinally extending spacing members 14: may be located between the tongue wedges 10 and the yoke portions of the coils 2 and 3 to further assist in supporting and insulating the coils.

The tongue wedges, whileshown as comprising integral members of T-shape in cross-section, may

be constructed in separate 11( parts, that is to say, a separate horizontal plate 11 and a separate and abutting vertical web member 12.

By this arrangement, a very strong non magnetic coil support is obtained that will not become excessively heated to a degree sufficient to destroy the insulation with which it is in contact.

1 claim as my invention:

1. A transformer comprising a core mem ber, coil members inductively related there with, means for 1 preventing movement of said coils in a direction normal to their faces, and a non-magnetic supporting member having a cross-sectional area of substantially T-shape arranged to prevent end-Wise move ment of said coils.

2. A transformer comp-rising a plurality of core members, a plurality of coil members inductively related therewith, means for preventing movement of said coils in the direction normal to their faces, and a non-magnetic supporting member having a horizontally disposed portion adapted to engage said coils and a vertically disposed portion adapted to extend between said cores for preventing end-Wise movement of said coils. 3; A transformer comprising a plurality of core members having a plurality of coil members inductively related therewith, frame members arranged to secure said core members together, aplurality of-nori-magnetic supporting members disposed between said frame members and said coil members and means for forcing said supporting members into engagement with said frame members and said coils to prevent end-v7ise movement of said coils.

In testimony whereof, I have hereunto subscribed my name this first day of No- 40 vember, 1920.

GUERNEY H. COLE.

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