Patent Publication Number: US-4837543-A

Title: Transformer core and coil support assembly

Description:
BACKGROUND OF THE INVENTION 
     The invention relates to supporting structure for the core and coil assembly of a transformer. 
     Known support structures in use today rest on the bottom of the transformer tank. As a result, the bottom plate of the transformer tank supports the weight of the core and coil assembly. 
     Attention is directed to the following U.S. Pat. Nos.: 
     
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Arli et al.   4,631,509   Dec. 23, 1986                                   
Lee           4,673,907   Jun. 16, 1987                                   
Reinebach     4,172,964   Oct. 30, 1979                                   
Glassanos     3,270,305   Aug. 30, 1966                                   
Wald          2,511,230   June 13, 1950                                   
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     Attention is also directed to British Pat. No. 439,901. 
     SUMMARY OF THE INVENTION 
     The invention provides a transformer comprising a tank and a core and coil assembly. The core and coil assembly includes a core having spaced-apart vertical portions and spaced-apart horizontal portions extending between the vertical portions. The core portions define a core window. The core and coil assembly also includes a coil wound around each of the vertical portions of the core. 
     The transformer also comprises a support member or beam which extends through the core window, which supports the core and coil assembly and which is supported by the side walls of the tank. More particularly, the support member or beam has an I-shaped cross section and includes a horizontal upper flange, a horizontal lower flange, and a vertical web extending between the flanges. The opposite ends of the support member are supported by brackets fixed to the side walls of the tank. 
     The upper portion of the core is supported by the upper flange. In other words, the upper portion of the core rests on top of the upper flange of the beam. As a result, the vertical portions of the core hang from the upper Portion and are therefore in tension, unlike in known prior art constructions. Placing the vertical portions of the core in tension reduces the increased losses that result when the vertical portions are in compression. 
     The coils are supported by the lower flange of the beam. The height of the coils is approximately equal to the height of the web Portion of the support member, and the inner portions of the coils, i.e., the portions within the core window, extend between the upper and lower flanges of the support member. The support member is made from an insulating material and acts as an insulator between the coils and also from coil to core ground. The support member also anchors and supports connecting leads extending from the coils. 
     Other features and advantages of the invention will become apparent to those skilled in the art upon review of the following detailed description, claims and drawings. 
    
    
     DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a perspective view, partially cut away, of a transformer embodying the invention and comprising a coil and core assembly and a support member therefor. 
     FIG. 2 is a partial vertical cross sectional view of the transformer. 
     FIG. 3 is a perspective view of the support member. 
     FIG. 4 is a vertical cross sectional view of the support member. 
    
    
     Before one embodiment of the invention is explained in detail, it is to be understood that the invention is not limited in its application to the details of construction and the arrangements of components set forth in the following description or illustrated in the drawings. The invention is capable of other embodiments and of being practiced or being carried out in various ways. Also, it is to be understood that the Phraseology and terminology used herein is for the Purpose of description and should not be regarded as limiting. 
     DESCRIPTION OF THE PREFERRED EMBODIMENT 
     A transformer 10 embodying the invention is illustrated in the drawings. 
     The transformer 10 comprises a tank 12 having a bottom 13 and a side wall or walls 14. The transformer 10 also comprises a core 16 including (see FIG. 2) first and second or left and right spaced-apart, generally vertical portions 18 and 20 and upper and lower spaced-apart, generally horizontal portions 22 and 24 extending between the vertical portions. The vertical and horizontal portions 18, 20, 22 and 24 define a core window 26. The transformer 10 also comprises first and second or left and right coils 28 and 30 respectively wound around the left and right vertical portions 18 and 20 of the core 16. The transformer 10 as thus far described is conventional. 
     The transformer 10 also comprises an elongated support member or I-beam 32. The I-beam 32 is made of a strong insulating material and includes left and right (as shown in FIG. 3) ends 34 and 36, a horizontal upper flange 38 including first and second or left and right (as shown in FIG. 4) flange portions 40 and 42, a horizontal lower flange 44 including first and second or left and right (as shown in FIG. 4) flange portions 46 and 48, and a vertical web 50 extending between and connecting the flanges 38 and 44. 
     The I-beam 32 is supported above the bottom 13 of the tank 12 by the side walls 14 of the tank 12. More particularly, the side walls 14 of the tank 12 have thereon (see FIG. 1) diametrically opposed, lower brackets 52 (only the right bracket 52 is shown) supporting the opposite ends 34 and 36 of the I-beam 32. Each lower bracket 52 has a U-shaped vertical cross section and includes a horizontal base 56 and spaced, vertical portions 58. In the Preferred embodiment, the web 50 of the I-beam 32 extends beyond the flanges 38 and 44 at both ends of the I-beam 32 (this is best shown in FIG. 3), and each end of the web 50 rests on the base 56 of a bracket 52 between the vertical Portions 58 thereof (as shown in FIG. 1). The side walls 14 of the tank 12 also have thereon (see FIG. 1) diametrically opposed, upper brackets 60 and 62 laterally supporting the left and right ends, respectively, of the I-beam 32. More particularly, each bracket 60 or 62 has a U-shaped horizontal cross section and includes a base 64 and spaced, horizontal portions 66 extending on opposite sides of the web 50 of the I-beam 32. The upper brackets 60 and 62 prevent horizontal movement of the I-beam 32 but do not support the weight of the I-beam 32. 
     The I-beam 32 extends through the core window 26 and supports the core 16 and the coils 28 and 30 above the bottom 13 of the tank 12. In other words, the I-beam 32 supports the weigh of the core 16 and the coils 28 and 30. More particularly, the core 16 is wound around the I-beam 32 and the upper portion 22 of the core 16 rests on the upper flange 38 of the I-beam 32. The left and right coils 28 and 30 rest on the left and right portions, respectively, of the lower flange 44. Thus, the I-beam 32 supports the coils 28 and 30 independently of the core 16. Alternatively stated, the weight of the coils 28 and 30 is transferred directly to the lower flange 44 of the I-beam 32 and is not transferred to the I-beam 32 through the core 16. The portions of the coils 28 and 30 within the core window 26 extend between the upper and lower flanges 38 and 44 and the web 50 separates the coils 28 and 30. 
     The I-beam 32 also includes means for fixing the position of the core 16 (and therefore the coils 28 and 30) axially of the 1-beam 32. While various suitable means can be employed, in the preferred embodiment, such means includes notches or recesses 70 in the flange portions 40, 42, 46 and 48 of the I-beam 32. As shown in the drawings, the core 16 extends into the notches 70 so that the opposite ends of the notches 70 prevent movement of the core 16 axially of the I-beam 32. 
     The I-beam 32 transfers the weight of the core 16 and coils 28 and 30 to the side walls 14 of the tank 12 and keeps the weight of the core 16 and coils 28 and 30 off the bottom 13 of the tank 12. Also, the I-beam 32 acts as an insulator between the coils 28 and 30 and also from coil to core ground. Furthermore, the I-beam 32 can anchor and support connecting leads (not shown) extending from the coils 28 and 30. 
     Various feature of the invention are set forth in the following claims.