Patent Application
20170018354
The yoke laminations of transformer cores are generally clamped by structural members made of steel. Channel-shaped sections, or brackets, are commonly employed for this purpose. The brackets are generally secured by tie rods, which may be tightened to clamp the yoke between the channel brackets. Brackets, however, may not exert uniform pressure along the yoke. As tie rods are tightened on either side of the laminations, it can cause the middle of the channel bracket span to bow outward, away from the laminations. Yoke bolts, which pass through the lamination layers, are also commonly used. The use of yoke bolts can result in higher core losses and a risk of failure due to shorting the yoke laminations. When pressure is not applied uniformly along the laminations, it may lead to bulging, dimensional problems, and the generation of unwanted sound. A bracket capable of applying even pressure, without passing bolts through the lamination layers, is therefore be desired.
In an exemplary embodiment, transformer core bracket tension bar may be provided. The tension bar may be an elongated, bow-shaped flat bar configured to be affixed along a longitudinal axis of a channel bracket. The bar may further include at least one tightening bolt, which may be adjustably disposed through the bar. The at least one tightening bolt may be configured to apply pressure to a side of the channel bracket, opposite the yoke, when tightening.
In another exemplary embodiment, a transformer core bracket may be provided. The bracket may include two channel brackets configured to align adjacent each side of a yoke. The channel brackets may be tied together by at least one tie rod at each end of the channel brackets, such that the yoke is clamped between the brackets. The bracket may further include at least one tension bar, which may be an elongated, bow-shaped flat bar configured to be affixed along a longitudinal axis of a channel bracket. The bar may further include at least one tightening bolt, which may be adjustably disposed through the bar. The at least one tightening bolt may be configured to apply pressure to a side of the channel bracket, opposite the yoke, when tightened.
In a further exemplary embodiment, a method for applying pressure more uniformly with the core bracket may be provided. The method may include clamping a yoke between two channel brackets, affixed by tie rods at each end. The channel brackets may have at least one tension bar configured to adjust the deflection of the channel brackets. The method may further include manipulating the tension bar to adjust the deflection of the channel brackets.
Advantages of embodiments of the present invention will be apparent from the following detailed description of the exemplary embodiments. The following detailed description should be considered in conjunction with the accompanying figures in which:
Aspects of the present invention are disclosed in the following description and related figures directed to specific embodiments of the invention. Those skilled in the art will recognize that alternate embodiments may be devised without departing from the spirit or the scope of the claims. Additionally, well-known elements of exemplary embodiments of the invention will not be described in detail or will be omitted so as not to obscure the relevant details of the invention.
As used herein, the word “exemplary” means “serving as an example, instance or illustration.” The embodiments described herein are not limiting, but rather are exemplary only. It should be understood that the described embodiments are not necessarily to be construed as preferred or advantageous over other embodiments. Moreover, the terms “embodiments of the invention”, “embodiments” or “invention” do not require that all embodiments of the invention include the discussed feature, advantage or mode of operation.
Referring to exemplary
Tension bar 110 may further include at least one tightening bolt 112, which may adjustably pass through tension bar 110. The at least one tightening bolt 112 may be of an appropriate length to apply pressure on a channel bracket 120, 122 when tightened through tension bar 110, as would be understood by a person having ordinary skill in the art. In some embodiments, tension bar 110 may include two tightening bolts 112. The at least one tightening bolt 112 may be positioned at a desired location along the length of tension bar 110. In some exemplary embodiments having multiple tightening bolts 112, bolts 112 may be spaced evenly along the length of tension bar 110. In an exemplary embodiment, the at least one tightening bolt 112 may be adjustably engaged with tension bar 110, such that the distance tightening bolt 112 protrudes on either side of tension bar 110 may be adjusted. In some exemplary embodiments, tightening bolt 112 may be threadably engaged with tension bar 110. The at least one bolt 112 may be of appropriate length that the ends of bolt 112 may contact channel bracket 120, 122 when tightened through tension bar 110. The at least one bolt 112 may apply pressure on channel bracket 120, 122, which may in turn prevent channel bracket 120, 122 from bulging away from the laminations 130 due to outward pressure from the laminations 130.
In an exemplary embodiment, tension bar 110 may create a deflection in channel bracket 120, 122 in the opposite direction from the deflection caused by the pressure of the yoke laminations, as shown in
In some exemplary embodiments, as shown in exemplary
The foregoing description and accompanying figures illustrate the principles, preferred embodiments and modes of operation of the invention. However, the invention should not be construed as being limited to the particular embodiments discussed above. Additional variations of the embodiments discussed above will be appreciated by those skilled in the art.
Therefore, the above-described embodiments should be regarded as illustrative rather than restrictive. Accordingly, it should be appreciated that variations to those embodiments can be made by those skilled in the art without departing from the scope of the invention as defined by the following claims.
