US2918639A - Spacer for electrical windings - Google Patents

Description

Dec. 22, 1959 o. H. BEYMER 2,918,639

SPACER FOR ELECTRICAL WINDINGS Filed May 15, 1957 United States Patent SPACER FOR ELECTRICAL WINDINGS Oliver H. Beymer, Pittsfield, Mass., assignor to General Electric Company, a corporation of New York Application May 15, 1957, Serial No. 659,261

Claims. (Cl. 336-185) This invention relates to a stationary electrical induction apparatus, and more in particular to an improved spacing arrangement for axially spacing disk-shaped coils of transformers and the like.

In one form of the transformer, the windings are comprised of a plurality of axially displaced disk-shaped coils, the coils generally being serially connected. Each of the disk-shaped coils comprises one or more conductor turns. The coils surround a cylindrical winding member of insulating material, and elongated axially extending spacing members separate the coils from the winding cylinder to provide cooling ducts. The coils are axially displaced in order to provide for proper cooling as well as to insure sufficient insulation therebetween, and in order to maintain the separation of the coils against mechanical displacement or displacement caused by electromagnetic forces in the transformer, it is customary to insert radially extending spacers between the coils.

In the past, various means have been employed for axially spacing the coils. In one conventional spacing arrangement, the axially extending spacing members have a generally T-shaped cross section with the widest portion of the spacing member being away from the winding cylinder. Flat generally rectangular insulating spacers are provided keyed to the T-shaped axially extending spacing member, or tie strip, the fiat spacers, otherwise referred to as keyspacers, having recesses in one end thereof that match the cross section of the tie strip.

The key spacers are only held in position by small projections engaging the tie strip, and these projections may become broken due to excessive pounding of the spacers that may arise, for example, from arc-back in rectifier transformers, or from short circuiting of the electrodes connected to are furnace transformers. The assembly of the key spacers is also time-consuming, since each spacer must be slid along a tie strip from one end thereof to its final position in the winding.

In another spacing arrangement, the axial spacers are comprised of U-shaped members having legs extending between the coils and apexes extending around the radially inner edges of the coils. These spacers are axially aligned so that the legs of adjacent spacers contact each other, the aligned groups of spacers extending axially of the winding between the tie strips. While this type of spacer is more economical than the key spacer, it need not be slide along a tie strip, andis completely locked from radial movement, but it is not keyed in alignment when stacked, and may therefore slide out of the spacer row under pounding conditions, and drift around the inside periphery of the coil.

It is therefore an object of this invention to provide an improved means for axially spacing disk-spaced coils of an electrical winding.

It is also an object to provide spacing means for axially spacing disk-shaped coils of an electrical winding, the. spacing means being easily assembled in the ICC winding during fabrication thereof, and being firmly locked against radial and circumferential displacement.

Briefly stated, according to one aspect of my invention, I provide a winding for an electrical induction apparatus such as a transformer or reactor. The winding is comprised of a plurality of axially aligned disk-shaped coils disposed on a winding cylinder. A plurality of elongated axially extending spacing members space the coils from the cylinder to provide the cooling ducts therebetween. Means are provided for axially spacing the coils, the axial spacing means comprising U-shaped members of insulating material, such as rolled pressboard. The U- shaped members have leg portions extending radially between the coils and apex portions extending around the inner radial edges of the coils. The apexes of the U- shaped members are notched and the axially extending spacing members extend through the notches to prevent circumferential displacement of the U-shaped members.

While the specification concludes with claims particularly pointing out and distinctly claiming the subject matter which I regard as my invention, it is believed that the invention will be better understood from the following description taken in connection with the accompanying drawing.

In the drawing:

Fig. l is a side elevational view of a portion of an electrical winding embodying the spacing arrangement of my invention,

Fig. 2 is a top view of the winding of Fig. 1,

Fig. 3 is a perspective view of a notched U-shaped spacer according to my invention,

Fig. 4 is an enlarged view of a portion of the winding of Fig. l,

Fig. 5 is a cross-sectional view of the portion of the Winding of Fig. 4,

Fig. 6 is an enlarged view of a modification of the arrangement of Fig. 4,

Fig. 7 is a cross-sectional view of the portion of the winding illustrated in Fig. 6,

Fig. 8 is an end view of a portion of a winding and illustrating a modification of the notched U-shaped spacer of my invention, and

Fig. 9 is an end view of a portion of electrical winding and illustrating another modification of the notched U- shaped spacer of my invention.

Referring now to the drawings and more in particular to Fig. 1, therein is shown an electrical winding comprising a plurality of disk- shaped coils 10, 11, 12, 13 and 14. The coils are axially aligned and surround an insulating cylinder 15. A plurality of axially extending elongated spacing members 16 are provided on the outer circumference of the winding cylinder 15 to space the coils from the cylinder and provide a cooling duct therebetween. The spacing members 16 are preferably equal.- ly spaced circumferentially on the cylinder 15. The winding cylinder 15 surrounds a magnetic core 18 ac-' cording to the conventional practice.

The coils 10, 11, 12, 13 and 14 are. axially spaced apart by insulating spacing members 20. As illustrated in Fig. 3, the separator elements or spacing members 20 are comprised of a U-shaped member of insulating material having flat rectangular leg portions 21 joined by an apex or arms portion 22. The apex portion 22 of U-shaped member 20 is provided with a notch 23 extending completely through the insulation and leaving. only edge portions or arms 24 bridging the shorter sides of leg portions 21. The U-shaped member 20 may be formed of a plurality of layers of insulating material, such as pressboard, molded to a U-shape, the notch 23 being. formed by any conventional manner such as punching before forming the member into a U-sh-ape or saw-,

ing after the member has been formed into a U-shape.

Referring now to Figs. 4 and 5 which illustrate the spacer of Fig. 3 as it may be employed in a continuously wound winding, the U-shaped members 20 are assembled on alternate coils 11 and 13 with their leg portions 21 extending radially between the adjacent coils and their apex portions 22 extending around the inner radial edges of the coils 11 and 13. The U-shaped members 20 are axially aligned, and the axially extending spacing members 16 extend through the notches 23 of the U-shaped members 20.

As illustrated in Figs. 4 and 5, the coil 14 is an end coil of the winding and an L-shaped insulating member 30 is provided having one portion extending along the side of the coil 14 away from the other coils, and another arm 32 extending between the coil 14 and the cylinder 15. The L-shaped member 30 is notched in the same manner as the U-shaped members 20.

Referring now to Figs. 6 and 7, therein is illustrated a modification of the arrangements of Figs. 4 and 5, the modification of Figs. 6 and 7 being especially adapted for use on a winding having preformed disk-shaped coils. In this arrangement, the U-shaped members 20 surround each of the coils 40, 41 and 42 of the winding on the insulating stacking cylinder 43, so that the leg portions of the U-shaped members surrounding adjacent coils are in contacting relationship.

Referring now to Fig. 8, therein is illustrated a modified form 50 of U-shaped spacer having diamond-shaped legs. The notches of the spacers 50 engage axially extending spacers 16 disposed on opposite sides of a duct 17 through which one or more leads 51 extend. The diamond-shaped legs of the spacers 50 are disposed so that the outer circumferential spacing of their edges is substantially the same as their inner circumferential spacing. This arrangement, as more fully disclosed in U.S. Letters Patent 2,467,804, which issued on my application and is assigned to the assignee of the present invention, provides increased support for the radially outer edges of the coils when it is necessary to provide room for the accommodation of leads in the duct 17.

In a variation of the arrangement of Fig. 9, the legs of the U-shaped spacers 55 are curved instead of diamond-shaped, and may thus be readily formed from arcuate shaped sections of insulating material. This shape may be more easily formed than the three sided insulation section necessary to form the diamond legged U-shaped member 50 of Fig. 8.

In winding a continuously wound coil (as illustrated in Figs. 4 and 5) employing the U-shaped spacer of Fig.

3, the apexes 22 of the spacers 20 are positioned around the radially inner conductor of the upwound coils (such as coils 11 and 13) by a single outward radial movement thereof with respect to said coils, as the conductor is wound on the axially extending spacers 16. The spacers 20 are positioned so that their notches 23 engage the axially extending spacers 16. The remainder of the conductor turns of the upwound coils are then wound between the leg portions of the U-shaped spacers. No U-shaped spacers are provided on the down-wound coils, such as coils 12 and 14, since these coils are upset after they are wound. On end coils, such as coil 14, an L- shaped insulation member 30 may be employed, one arm 32 of the member 30 being notched and positioned around the radially inner edge of the coil 14 and engaging the axially extending spacing member 16.

When employing the U-shaped member 20 on a wind ing having preformed coils, such as the winding of Figs. 6 and 7, the U-shaped members are positioned around the coils before they are slid over the stacking cylinder 43, so that when the coils are placed over the end of the stacking cylinder the notches 23 engage the axially extending spacing members 16.

It will be understood, of course, that, while the forms of my invention herein shown and described constitute preferred embodiments of the invention it is not intended herein to illustrate all of the possible equivalent forms or ramifications thereof. It will also be understood that the words used are words of description rather than of limitation, and that various changes may be made without departing from the spirit or scope of the invention herein disclosed, and it is aimed in the appended claims to cover all such changes as fall within the true spirit and scope of the invention.

What I claim as new and desire to secure by Letters Patent of the United States is:

1. A winding for stationary electrical induction apparatus comprising an insulating winding cylinder, a plurality of axially-extending elongated spacing members circumferentially spaced apart disposed on the outer surface of said cylinder, a plurality of axially aligned diskshaped coils of predetermined thickness surrounding said cylinder and disposed in contacting relationship with said spacing members, said spacing members radially separating said coils from said cylinder, and means for axially separating said coils comprising a plurality of U-shaped members, each of said U-shaped members having substantially parallel legs and a bight portion integrally connecting said legs, said legs being spaced apart by said bight portion a distance substantially equal to the thickness of said coils, each of said U-shaped members having a notch formed in the bight portion thereof, said notch being defined by inner sides of said bight portion that face each other, said sides being straight and parallel to each other throughout their entire extent, so that said elongated spacing members are radially receivable therein, the U-shaped members being placed over said coils in circumferentially spaced relationship with the legs thereof in contacting relationship with said coils, and the bight portions of said U-shaped members being disposed around the inner edges of said coils to prevent movement of said U-shaped members outwardly radially of said coils, said axially extending spacing members being confined within the notches on said U-shaped members to prevent circumferential displacement of said U-shaped members, whereby said U-shaped members are easily installable over said coils by a single outward radial movement thereof with respect to said coils, yet said U-shaped members are substantially immovably locked in said apparatus after insertion of said axially extending spacing members into said notches.

2. The winding of claim 1 in which the U-shaped members are in axially aligned groups equally spaced circumferentially about said winding, and the U-shaped members in said groups surround alternate coils.

3. The winding of claim 1 in which the U-shaped members are in axially aligned groups equally spaced circumferentially about said winding, and the U-shaped members in each group surround adjacent coils so that the leg portions of adjacent U-shaped members are in contacting relationship.

4. The winding of claim 1 in which the U-shaped members are in axially aligned groups spaced about the circumference of said winding, the inner and outer circumferential spacing between the U-shaped members of a pair of adjacent said groups being substantially the same.

5. In a stationary electrical induction apparatus of the type having a plurality of disk-shaped coils of predetermined thickness axially disposed on an insulating winding cylinder and spaced from said cylinder by a plurality of axially extending spacing means, the improvement in means for separating the disk-shaped coils comprising a separator element of generally rectangular outer configuration formed from fiat insulating material, said separator element being U-shaped and having a pair of parallel legs integrally joined by a bight portion, said legs being spaced apart by said bight portion a distance approximately equal to thi lhls kness of said disk-shaped coils, said bight portion consisting of a pair of laterally spaced arms bridging the space between said legs, each of said arms having straight, smooth, parallel inner surfaces that face each other so as to define a notch with sides parallel to the outer configuration of said U-shaped member, said notch being dimensioned so that said axially extending spacing means is radially receivable therein, whereby said separator element is installable over a diskshaped coil by a single outward radial movement thereof with respect to said coil, and said separator element is 10 2,467,804

locked into substantially immovable relationship to said apparatus by radially inserting said axially extending spacing means into the parallel surfaced notch in the bight portion of the separator element.

References Cited in the file of this patent UNITED STATES PATENTS Cummings July 15, 1919 Beymer Apr. 19, 1949 UNITED STATES PATENT OFFI'CE CERTIFICATE OF CGRRECTION December 22, 1959 Patent No, 2,918,639

Oliver H Beymer It is hereby certified that error appears in the-printed specification of the above numbered patent requiring correction and that the said Letters Patent should read as corrected below.

Column 1, line 61, for "slide" read slid column 2, line 63, for "arms" read bight Signed and sealed this 24th day of May 1960.,

(SEAL) Attest:

KARL AXLINE ROBERT c. WATSON Commissioner of Patents Attesting Officer UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent N0o 2,918,639 December 22, 959

Oliver H Be ymer It is herebfi certified that error appears in the-printed specification of the above numbered patent requiring correction and that the said Letters Patent should read as corrected below.

(301mm 1, line 61, for "slide" read slid column 2, line 63, for "arms" reed bight e Signed. and sealed this 24th day of May 1960.,

Attest:

KARL H, AXLINE ROBERT C. WATSON Attesting Ofl lcer Commissioner of Patents

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