US2544845A - Transformer construction - Google Patents

Description

Patented Mar. 13, 1951 TRANSFORMER CONSTRUCTON Edwin A. Link, Milwaukee, Wis., assigner to McGraw Electric Company, a corporation of Delaware Application September 13, 1948, Serial No. 49,023

2 Claims.

This invention relates to transformer constructions.

In constructing a transformer it is the usual practice to provide a plurality of ducts to provide for the circulation of oil or other cooling medium. The practice heretofore followed is to place all of the ducts of a series in a single circumferential layer so that there are a plurality of adjacent ducts all located in this single circumferential layer. Of course, as many other series of ducts may be provided in the prior constructions as necessary, but in each instance each series is in a single circumferential layer.

In the prior constructions it is a relatively easy matter to accidently displace some of the spacing members which hold the successive layers apart and thereby form the duet, and when this occurs blocking of the adjacent ducts results. Also it is apparent that there is a considerable amount of vibration in all transformer constructions and loosening of the spacing members may occur, even after the transformer has been installed.

This invention is designed to overcome the above noted defects and objects of this invention are to provide a novel form of transformer construction in which the cooling ducts for the circulation of the cooling medium are formed in different circumferential layers and preferably only a pair of ducts is formed in any one layer by the use of a single spacing member of wood or other insulating material, although the invention in its broader aspect contemplates the provision of as many pairs of ducts in any given circumferential layer as desired provided the winding immediately embracing or surrounding a spacing member becomes tangent to the underlying layer prior to the positioning of another spacing member, so that each spacing member is tightly and rmly bound by a layer of the winding and the winding surrounding the single spacing member is drawn tightly into tangential engagement with the underlying layer and thus firmly binds and holds the spacing member against accidental displacement either during assembly and handling or after installation.

A further feature of this invention is to provide pairs of cooling ducts, each pair being obtained by the use of a single spacing member and to space both peripherally and radially the successive series of ducts to thus secure the most effective cooling for the least number of cooling ducts.

A further object is to provide a construction for the cooling ducts of transformers and the like which may be most easily produced.

An embodiment of the invention is shown in the accompanying drawings, in which:

Figure 1 is a side elevation of a transformer removed from its casing.

Figure 2 is a fragmentary, sectional View on the line 2--2 of Figure l, such view being drawn to an enlarged scale.

The core structure of the transformer is indicated by the reference character l and it may be a wound type of core structure, for instance as shown in the patent to Wiegand, No. 2,313,306 of March 9, 1943 for Method of Making Transfcrmers, such patent being owned by the assignee of this invention, or it may be formed as a stacked core. Preferably the core is cruciform in vcross-section so as to approximately lill the circular window of the conducting winding assembly, such conducting Winding assembly being indicated generally by the reference character 2. This conducting winding assembly may be wound in any suitable manner, for instance, as shown in the above noted patent, and may comprise an inner circular insulating shell'3 on which the two windings 4 and 5 of the transformer are carried.

During winding of the transformer, insulating spacing members of wood or other suitable material as indicated by the reference characters 6 and 'l may be positioned as shown in detail in Figure 2. It is to be noted that the spacing members are so arranged, as shown in Figure 2, that only one spacing member is positioned in each layer and that the successive spacing members are radially spaced as Well as circumferentially spaced. Also if desired one group of spacing members, for instance the spacing members l may be located on one side of the winding and another group of spacing members, for instance the spacing members l, may be located on the other side of the winding. In addition to this, a larger or a smaller number of spacing members could be employed throughout the entire winding, if desired, or found necessary for the particular design or size oi transformer employed.

Under all conditions, it is to be understood that it is contemplated that the overlying layer of the winding located outside of a spacing member becomes tangent to the underlying layer before another spacing member is positioned, even if a plurality of spacing members are employed for any given layer. However, in the particular formY of the invention chosen for illustration only a single spacing member has been shown for a single layer.

By following the construction outlined above and illustrated, particularly in Figure 2, it will be seen that the spacing members are rmly anchored in place and are held in their vertical y position at all times against accidental displacement either during assembly or installation or during use of the transformer. lfhere is no chance of a spacing member shifting and blocking any of the ducts as has heretofore been the case. Instead each spacing member is irmly underlying layer on each side of the spacing'- member, thus precluding shifting'of the spacing-f member.

The spacing members eXtend'beyond-'theupper and lower edges of the Winding asV shown in Figure 1.

It will be seen that each spacingmember is so arranged that it provides two ducts for the circulation of the cooling oil o r other mediumV and that it is impossible for the spacing members to'shiftand block the ducts:

It' will be seen that the construction isi veryA simple and does not materially. increase the bulkiness of the winding assembly.

It is distinctly understood that although the invention hasl beenr described asy primarily intended for transformer construction, that nevertheless it could be followed for any type of 'electromagnetic winding Where cooling ducts are employed.

Although. this invention has been described inconsiderable detail, itis to ber understood that such description is intended as illustrative rather than limiting,` asthe-invention may be variously embodied and is -to be interpreted as claimed.

Iv claim:

1. In an electromagnetic device, a winding having a plurality of layers, and a plurality of longitudinally extending spacing membersr lo cated between successive'layers with each successive spacing member spacedcircumferentially and radially from-every` other spacing member eci to form a series of pairs of ducts, each individual pair of ducts being adjacent one spacing member only and being remote from all otherspacing members.

2. In a transformer construction, a core having at least one leg, a Winding assembly having aV pair ofzwindings surrounding such leg and constituting primary and secondary windings with each winding having a plurality of layers, and at least two -series of longitudinally extending spacing members circumferentially spaced with reference to the; windingVv assembly with one series of spacing members located between successive layers 'of' the primary Winding and the other series of spacing members located between successive layers ofthe secondary winding and withthe.` two series spaced circumferentially from each other.

andwith each spacing member circumierentially spaced from everyf other spacing member to form a series of pairs of ducts, each individual pair of ducts being adjacent one. spacing member only and being remote from all other spacing members and with any overlying layer of windingtangent to an underlying layer of-Wind- A ing` adjacent eaclrspacing member;

EDWIN A. LINK. .t

REFERENCES: CITED The following references' are of 'record' in the le oflth' patent:

UNITED STATES v PATENTS Number Name Date 829,780 Hall Aug. 28, 1906 1,411,619 Frank Apr. 4, 1922 2,142.2;0'375 Paluev June-10, 1947'

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