Claims:1. A busbar expansion unit (3) comprising:
one or more flanges;
an incoming bus duct (11) and a corresponding outgoing bus duct (12) associated with a busway (1);
wherein one or more phases at the one or more flanges are connected between said incoming bus duct (11) said corresponding outgoing bus duct (12) through one or more flexible conductors (2); and
wherein said one or more phases at the one or more flanges along with the one or more flexible conductors (2) are encapsulated within an open-ended box (3) mounted onto said incoming bus duct (11).

2. The busbar expansion unit as claimed in claim 1, wherein said open ended box (3) comprises a top holder plate (31) and a bottom holder plate (32).

3. The busbar expansion unit as claimed in claim 1, wherein said corresponding outgoing bus duct (12) comprises a concentric plunger adapted to internally connect with said open ended box (3).

4. The busbar expansion unit as claimed in claim 3, wherein the concentric plunger is adapted to perform a relative longitudinal motion with respect to the open ended box (3) such that the flexible conductors (2) bend so as to maintain electrical continuity.

5. The busbar expansion unit as claimed in claim 4, wherein the concentric plunger comprises a specially shaped liner adapted to maintain positive pressure with one or more inner surfaces of the busbar expansion unit.

6. The busbar expansion unit as claimed in claim 1, wherein each of said one or more flexible conductors (2) comprises one or more insulator pins (33) such that each of said one or more flexible conductors (2) bows towards only one direction.

7. The busbar expansion unit as claimed in claim 1, wherein corresponding outgoing bus duct (12) comprises one or more stoppers (5) and one or more springs (6) adapted to limit expansion or contraction of the busbar expansion unit.

8. The busbar expansion unit as claimed in claim 1, wherein said one or more phases at the flanges are electrically isolated by one or more inter-phase barriers (37).
, Description:TECHNICAL FIELD
[0001] The present disclosure relates to the field of electrical power distribution systems of the type commonly referred to as busways, and more specifically relates to, busway building expansion section busbar expansion unit/ joint for the purpose of ingress protection and absorbing the expansion.

BACKGROUND
[0002] Background description includes information that may be useful in understanding the present invention. It is not an admission that any of the information provided herein is prior art or relevant to the presently claimed invention, or that any publication specifically or implicitly referenced is prior art.
[0003] A distribution system is a system that distributes electrical power throughout a building. Distribution systems are used in every residential, commercial, and industrial building. A distribution system consists of metering devices to measure power consumption, main and branch disconnects, protective devices, switching devices to start and stop power flow, conductors, and transformers. Power may be distributed through various switchboards, transformers, and panel boards. Good distribution systems don’t just happen. Careful engineering is required so that the distribution system safely and efficiently supplies adequate electric service to both present and possible future loads. Commercial and industrial distribution systems use several methods to transport electrical energy. These methods may include heavy conductors run in trays or conduit. Once installed, cable and conduit assemblies are difficult to change. Power may also be distributed using bus bars in an enclosure. This is referred to as busway. Busway is defined by the National Electrical Manufacturers Association (NEMA) as a prefabricated electrical distribution system consisting of bus bars in a protective enclosure, including straight lengths, fittings, devices, and accessories. Busway (interchangeably referred as bus duct or bus bar) is mainly used in large public buildings, high-rise buildings the supply and distribution system, the switch box is inserted for electrical power distribution busway system lead unit, which is inserted through the box pin row bus bar and the copper busbar tight junctions to achieve. Busway includes bus bars, an insulating and/or support material, and housing. Bus ducts are used in commercial and industrial settings, both indoors and outdoors. In electrical power distribution, a bus duct (also called busway), is a sheet metal duct containing either copper or aluminum busbars for the purpose of conducting a substantial current of electricity. It is an alternative means of conducting electricity to power cables or cable bus. Bus ducts are used in commercial and industrial settings, both indoors and outdoors. Manufacturers deliver them assembled in large segments for electrical contractors to connect and support.
[0004] The busbar power supply systems is an important delivery channel for important occasions transport buildings, hospitals, industrial plants, stadiums, convention centers or airports, railway stations, commercial plaza, and other powerful electricity. With the development of modern industry, more and more widely busbar, wiring between different buildings, etc., you will need busbar expansion unit, for absorbing the axial direction due to changes in the amount of thermal expansion busbar solve additional stress due to temperature difference is caused by mechanical vibrations, it acts as an elastic compensating element. For example, when the length exceeds 80m busbar can be mounted a busbar expansion unit.
[0005] Normally in short runs of busway, such as 30 feet or less, the effect of thermal expansion, even when accumulative amounts thereof are considered, is not significant enough to cause any problem. Thermal expansion, however, can become a problem in longer runs of busway as well as in those installations wherein both ends of the busway are fixed either horizontally or vertically, such as by being fixed to or abutting against a portion of a building. The forces created as the result of thermal expansion have been, for example, strong enough in those installations wherein both ends of the busway are fixed to cause the individual bus bars to bow outwardly resulting in failures due to breakdowns in insulation, etc. With vertically mounted busway systems wherein the busway housing is supported at each individual floor as it passes there through, the forces created as a result of thermal expansion have been strong enough to cause some of the supports to rip out and thereby force the remainder of the supports to carry the entire weight of the busway system which they may or may not be able to do, but which in any event is undesirable.
[0006] The most common means for compensating for this thermal expansion has been the use of special expansion lengths" or sections, one or more of which is inserted in a busway run" or system. An example of such of the section or system is recited in a United States Patent 2727939A, entitled “Bus duct”. The patent discloses a means of achieving building expansion by using bent busbars connected through a flexible conductor enclosed in a rectangular housing. This embodiment seems to be designed for air insulated busways. Another example of special expansion lengths" or sections is recited in a United States Patent 3485936, entitled “Compact thermal expansion absorbing unit for electric power busways”. The patent discloses an improved thermal expansion device which may be installed in a run of riser busway without requiring for its installation any modifications in the busway system.
[0007] The use of special expansion sections is less than satisfactory, however, because the expansion section involves a construction which is bulky, more difficult to insulate, and expensive. The necessity for foreseeing the need for such special sections and the need for stocking, ordering, and installing such special sections add substantially to the time and cost of busway systems. Further, several techniques exist for compensating for movement between the building and the bus duct. The construction typically employs the use of flexible conductors fastened to both ends of the bus duct; these are encapsulated by rubber or metallic bellows or telescopic boxes. These designs are bulky, lack means of providing ingress protection, lack structurally strength for withstanding dynamic forces created during short-circuit. Furthermore, the prior-art does not mention about ways to achieve ingress protection at the movable regions. The existing technique also fails to provide structural supporting members and seems to be bulky. Additionally, the conventional busways mounted between building expansion joints are stressed and can bow leading to failure. Moreover, the conventional busways expansion joints limit the said expansion, as there is no use of stoppers.
[0008] Whereas there is certainly nothing wrong with existing busway, nonetheless, there still exists a need to provide an efficient, effective, reliable, and improved compensation mechanism for building expansion. Further, there is a need of means for compensating the difference between the thermal elongations of dissimilar materials used in busways. Furthermore, there is a need of a busbar expansion unit or busbar expansion joint for ingress protection.
[0009] All publications herein are incorporated by reference to the same extent as if each individual publication or patent application were specifically and individually indicated to be incorporated by reference. Where a definition or use of a term in an incorporated reference is inconsistent or contrary to the definition of that term provided herein, the definition of that term provided herein applies and the definition of that term in the reference does not apply.
[00010] In some embodiments, the numbers expressing quantities of ingredients, properties such as concentration, reaction conditions, and so forth, used to describe and claim certain embodiments of the invention are to be understood as being modified in some instances by the term “about”. Accordingly, in some embodiments, the numerical parameters set forth in the written description and attached claims are approximations that can vary depending upon the desired properties sought to be obtained by a particular embodiment. In some embodiments, the numerical parameters should be construed in light of the number of reported significant digits and by applying ordinary rounding techniques. Notwithstanding that the numerical ranges and parameters setting forth the broad scope of some embodiments of the invention are approximations, the numerical values set forth in the specific examples are reported as precisely as practicable. The numerical values presented in some embodiments of the invention may contain certain errors necessarily resulting from the standard deviation found in their respective testing measurements.
[00011] As used in the description herein and throughout the claims that follow, the meaning of “a,” “an,” and “the” includes plural reference unless the context clearly dictates otherwise. Also, as used in the description herein, the meaning of “in” includes “in” and “on” unless the context clearly dictates otherwise.
[00012] The recitation of ranges of values herein is merely intended to serve as a shorthand method of referring individually to each separate value falling within the range. Unless otherwise indicated herein, each individual value is incorporated into the specification as if it were individually recited herein. All methods described herein can be performed in any suitable order unless otherwise indicated herein or otherwise clearly contradicted by context. The use of any and all examples, or exemplary language (e.g. “such as”) provided with respect to certain embodiments herein is intended merely to better illuminate the invention and does not pose a limitation on the scope of the invention otherwise claimed. No language in the specification should be construed as indicating any non-claimed element essential to the practice of the invention.
[00013] Groupings of alternative elements or embodiments of the invention disclosed herein are not to be construed as limitations. Each group member can be referred to and claimed individually or in any combination with other members of the group or other elements found herein. One or more members of a group can be included in, or deleted from, a group for reasons of convenience and/or patentability. When any such inclusion or deletion occurs, the specification is herein deemed to contain the group as modified thus fulfilling the written description of all groups used in the appended claims.

OBJECTS OF THE INVENTION
[00014] An object of the present disclosure is to provide an improved compensation mechanism for building expansion.
[00015] Another object of the present disclosure is to provide a busway building expansion section for the purpose of ingress protection and absorbing the expansion.
[00016] Another object of the present disclosure is to provide a means of compensating the difference between the thermal elongations of dissimilar materials used in busways.
[00017] Another object of the present disclosure is to provide a busbar expansion unit or busbar expansion joint for ingress protection.
[00018] Another object of the present disclosure is to provide a busbar expansion unit or busbar expansion joint to withstand high short circuit levels.
[00019] Another object of the present disclosure is to provide a busbar expansion unit or busbar expansion joint with structural stoppers and springs to limit the motion and retract the assembly to the original position after releasing the load.
[00020] Another object of the present disclosure is to provide structural supports within the busbar expansion unit to take care of the dynamic forces created during a short circuit.

SUMMARY
[00021] The present disclosure relates to the field of electrical power distribution systems of the type commonly referred to as busways, and more specifically relates to, a busway building expansion section for the purpose of ingress protection and absorbing the expansion.
[00022] Embodiments of the present disclosure provide an efficient, effective, reliable, and improved busway expansion joint or section. Further, a busway building expansion section (interchangeably referred as busbar expansion unit) for the purpose of ingress protection and absorbing the expansion.
[00023] Accordingly, an aspect of the present disclosure relates to a busbar expansion unit. In an aspect, the busbar expansion unit can include one or more flanges, an incoming bus duct, and a corresponding outgoing bus duct. In another aspect, the incoming bus duct and a corresponding outgoing bus duct can be associated with a busway. In another aspect, one or more phases at the one or more flanges can be connected between said incoming bus duct said corresponding outgoing bus ducts through one or more flexible conductors. In another aspect, one or more phases at the one or more flanges along with the one or more flexible conductors can be encapsulated within an open-ended box mounted onto said incoming bus duct.
[00024] In an aspect, open ended box can include a top holder plate and a bottom holder plate.
[00025] In an aspect, outgoing bus duct can include a concentric plunger adapted to internally connect with said open ended box.
[00026] In an aspect, the concentric plunger can be adapted to perform a relative longitudinal motion with respect to the open ended box such that the flexible conductors bend so as to maintain electrical continuity.
[00027] In an aspect, the concentric plunger can include a specially shaped liner adapted to maintain positive pressure with one or more inner surfaces of the busbar expansion unit.
[00028] In an aspect, one or more flexible conductors can include one or more insulator pins such that each of said one or more flexible conductors bows towards only one direction.
[00029] In an aspect, wherein corresponding outgoing bus duct can include one or more stoppers and one or more springs adapted to limit expansion or contraction of the busbar expansion unit.
[00030] In an aspect, one or more phases at the flanges can be electrically isolated by one or more inter-phase barriers.
[00031] In contrast to the conventional busway, the present disclosure provides an improved compensation mechanism for building expansion. Further, in contrast to the existing busway, the present invention provides means for compensating the difference between the thermal elongations of dissimilar materials used in busways. Furthermore, in contrast to the existing busbar, the present invention provides a busbar expansion unit or busbar expansion joint for ingress protection.
[00032] Further, in contrast to the existing busbar expansion unit, the present invention limits the movement of the expansion unit by using a mechanism. Furthermore, the present invention provides structural supports within the busbar expansion unit to take care of the dynamic forces created during a short circuit.
[00033] Various objects, features, aspects and advantages of the inventive subject matter will become more apparent from the following detailed description of preferred embodiments, along with the accompanying drawing figures in which like numerals represent like components.

BRIEF DESCRIPTION OF THE DRAWINGS
[00034] The accompanying drawings are included to provide a further understanding of the present disclosure, and are incorporated in and constitute a part of this specification. The drawings illustrate exemplary embodiments of the present disclosure and, together with the description, serve to explain the principles of the present disclosure. The diagrams are for illustration only, which thus is not a limitation of the present disclosure, and wherein:
[00035] FIG. 1 illustrates general view of a proposed expansion unit, in accordance with an exemplary embodiment of the present disclosure.
[00036] FIG. 2 illustrates a plan view of a proposed expansion unit, in accordance with another exemplary embodiment of the present disclosure.
[00037] FIG. 3 illustrates a sectional view of a proposed expansion unit, in accordance with another exemplary embodiment of the present disclosure.
[00038] FIG. 4 illustrates a retracted and expanded position of the flexible biased by the biasing pins, in accordance with another exemplary embodiment of the present disclosure.
[00039] FIG. 5 illustrates a structural support arrangement, in accordance with another exemplary embodiment of the present disclosure.
[00040] FIG. 6 illustrates a typical bus duct route to achieve universal compensation of building expansion, in accordance with another exemplary embodiment of the present disclosure.

DETAILED DESCRIPTION
[00041] The following is a detailed description of embodiments of the disclosure depicted in the accompanying drawings. The embodiments are in such detail as to clearly communicate the disclosure. However, the amount of detail offered is not intended to limit the anticipated variations of embodiments; on the contrary, the intention is to cover all modifications, equivalents, and alternatives falling within the scope of the present disclosure as defined by the appended claims.
[00042] If the specification states a component or feature “may”, “can”, “could”, or “might” be included or have a characteristic, that particular component or feature is not required to be included or have the characteristic.
[00043] As used in the description herein and throughout the claims that follow, the meaning of “a,” “an,” and “the” includes plural reference unless the context clearly dictates otherwise. Also, as used in the description herein, the meaning of “in” includes “in” and “on” unless the context clearly dictates otherwise.
[00044] Exemplary embodiments will now be described more fully hereinafter with reference to the accompanying drawings, in which exemplary embodiments are shown. These exemplary embodiments are provided only for illustrative purposes and so that this disclosure will be thorough and complete and will fully convey the scope of the invention to those of ordinary skill in the art. The invention disclosed may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. Various modifications will be readily apparent to persons skilled in the art. The general principles defined herein may be applied to other embodiments and applications without departing from the scope of the invention. Moreover, all statements herein reciting embodiments of the invention, as well as specific examples thereof, are intended to encompass both structural and functional equivalents thereof. Additionally, it is intended that such equivalents include both currently known equivalents as well as equivalents developed in the future (i.e., any elements developed that perform the same function, regardless of structure). Also, the terminology and phraseology used is for the purpose of describing exemplary embodiments and should not be considered limiting. Thus, the present invention is to be accorded the widest scope encompassing numerous alternatives, modifications and equivalents consistent with the principles and features disclosed. For purpose of clarity, details relating to technical material that is known in the technical fields related to the invention have not been described in detail so as not to unnecessarily obscure the present invention.
[00045] Each of the appended claims defines a separate invention, which for infringement purposes is recognized as including equivalents to the various elements or limitations specified in the claims. Depending on the context, all references below to the "invention" may in some cases refer to certain specific embodiments only. In other cases it will be recognized that references to the "invention" will refer to subject matter recited in one or more, but not necessarily all, of the claims.
[00046] All methods described herein can be performed in any suitable order unless otherwise indicated herein or otherwise clearly contradicted by context. The use of any and all examples, or exemplary language (e.g., “such as”) provided with respect to certain embodiments herein is intended merely to better illuminate the invention and does not pose a limitation on the scope of the invention otherwise claimed. No language in the specification should be construed as indicating any non-claimed element essential to the practice of the invention.
[00047] Various terms as used herein are shown below. To the extent a term used in a claim is not defined below, it should be given the broadest definition persons in the pertinent art have given that term as reflected in printed publications and issued patents at the time of filing.
[00048] The present disclosure relates to the field of electrical power distribution systems of the type commonly referred to as busways, and more specifically relates to, a busway building expansion section for the purpose of ingress protection and absorbing the expansion.
[00049] Embodiments of the present disclosure provide an efficient, effective, reliable, and improved busway expansion joint or section. Further, a busway building expansion section (interchangeably referred as busbar expansion unit) for the purpose of ingress protection and absorbing the expansion.
[00050] Accordingly, an aspect of the present disclosure relates to a busbar expansion unit. In an aspect, the busbar expansion unit can include one or more flanges, an incoming bus duct, and a corresponding outgoing bus duct. In another aspect, the incoming bus duct and a corresponding outgoing bus duct can be associated with a busway. In another aspect, one or more phases at the one or more flanges can be connected between said incoming bus duct said corresponding outgoing bus ducts through one or more flexible conductors. In another aspect, one or more phases at the one or more flanges along with the one or more flexible conductors can be encapsulated within an open-ended box mounted onto said incoming bus duct.
[00051] In an aspect, open ended box can include a top holder plate and a bottom holder plate.
[00052] In an aspect, outgoing bus duct can include a concentric plunger adapted to internally connect with said open ended box.
[00053] In an aspect, the concentric plunger can be adapted to perform a relative longitudinal motion with respect to the open ended box such that the flexible conductors bend so as to maintain electrical continuity.
[00054] In an aspect, the concentric plunger can include a specially shaped liner adapted to maintain positive pressure with one or more inner surfaces of the busbar expansion unit.
[00055] In an aspect, one or more flexible conductors can include one or more insulator pins such that each of said one or more flexible conductors bows towards only one direction.
[00056] In an aspect, wherein corresponding outgoing bus duct can include one or more stoppers and one or more springs adapted to limit expansion or contraction of the busbar expansion unit.
[00057] In an aspect, one or more phases at the flanges can be electrically isolated by one or more inter-phase barriers.
[00058] In contrast to the conventional busway, the present disclosure provides an improved compensation mechanism for building expansion. Further, in contrast to the existing busway, the present invention provides means for compensating the difference between the thermal elongations of dissimilar materials used in busways. Furthermore, in contrast to the existing busbar, the present invention provides a busbar expansion unit or busbar expansion joint for ingress protection.
[00059] Further, in contrast to the existing busbar expansion unit, the present invention limits the movement of the expansion unit by using a mechanism. Furthermore, the present invention provides structural supports within the busbar expansion unit to take care of the dynamic forces created during a short circuit.
[00060] For the simplicity of understanding of the subject matter, following reference numerals are used for associated/corresponding feature/elements of the proposed circuit busbar expansion unit:

0. Building
1. Busway
11. Incoming bus duct
12. Outgoing bus duct
2. Flexible conductors
3. Expansion box
31. Box top holder plate
32. Box bottom holder plate
33. Biasing pins
34. Box supports
35. Locking pins
36. Guide plate
361. Slots
37. Interphase barriers
4. Guide pin
5. Stoppers
6. Spring
7. Gasket
8. Spring supports
9. Structural plate
91. Slots
[00061] In an embodiment, the present invention can include a flanges incoming bus duct and a corresponding outgoing bus duct. The corresponding phases at the flanges can be connected between the incoming and outgoing bus ducts through flexible conductors. The flanged section together with the flexible can be encapsulated within an open ended box rigidly mounted onto the incoming bus duct. The outgoing bus duct bears a concentric plunger which mates with the box from the inside. A relative longitudinal motion happens between the plunger and the box such that the flexible conductors bend. Thus, electrical continuity can be maintained while the bus duct compresses or expands together with the building.
[00062] FIG. 1 illustrates general view of a proposed expansion unit, in accordance with an exemplary embodiment of the present disclosure. As shown in FIG. 1, a busbar expansion unit (3) can include one or more flanges and an incoming bus duct (11) and a corresponding outgoing bus duct (12) associated with a busway (1). One or more phases at the one or more flanges can be connected between said incoming bus duct (11) said corresponding outgoing bus duct (12) through one or more flexible conductors (2). One or more phases at the one or more flanges along with the one or more flexible conductors (2) can be encapsulated within an open-ended box (3) mounted onto said incoming bus duct (11).
[00063] FIG. 2 illustrates a plan view of a proposed expansion unit, in accordance with another exemplary embodiment of the present disclosure. As shown in FIG. 2, a busbar expansion unit (3) can include one or more flanges and an incoming bus duct (11) and a corresponding outgoing bus duct (12) associated with a busway (1). One or more phases at the one or more flanges can be connected between said incoming bus duct (11) said corresponding outgoing bus duct (12) through one or more flexible conductors (2). One or more phases at the one or more flanges along with the one or more flexible conductors (2) can be encapsulated within an open-ended box (3) mounted onto said incoming bus duct (11).
[00064] FIG. 3 illustrates a sectional view of a proposed expansion unit, in accordance with another exemplary embodiment of the present disclosure. As shown in FIG. 3, the open ended box (3) can include a top holder plate (31) and a bottom holder plate (32). In an embodiment, the flexible conductors (2) can include one or more insulator pins (33) such that each of said one or more flexible conductors (2) bows towards only one direction. In another embodiment, one or more phases at the flanges can be electrically isolated by one or more inter-phase barriers (37).
[00065] In an embodiment, as the building expansion unit moves, the bus duct route moves along with it. This movement transmits through the said bus duct expansion section. A relative motion is expected between the incoming bus duct and the outgoing bus duct along the longitudinal axis. This motion translates to the plunger action between the guide plates (36) and the expansion box (3). This motion also translates to the compression or expansion of the flexible conductor within the confines of the geometry allowed by the biasing pins (33). The biasing pins can be made of a structurally strong insulating material like such as epoxy resin, polyurethane or structurally reinforced plastic. The flexible conductors bend only in the direction allowed by the biasing pins. These flexible conductors are fastened or welded to the ends of the corresponding phases. The inter-phase barriers (37) can allow for electrical isolation between the phases. The farthest location of the flexible conductors is restricted by the inter-phase barriers (37). These barriers can be placed between the slots of the top holder plate (31) and the bottom holder plate (32).
[00066] FIG. 4 illustrates a retracted and expanded position of the flexible biased by the biasing pins, in accordance with another exemplary embodiment of the present disclosure.
[00067] FIG. 5 illustrates a structural support arrangement, in accordance with another exemplary embodiment of the present disclosure. As shown in FIG. 5, corresponding outgoing bus duct (12) can include one or more stoppers (5) and one or more springs (6) adapted to limit expansion or contraction of the busbar expansion unit.
[00068] In an embodiment, a means of biasing the bending direction of flexible conductors (2) by confining it between a plurality of biasing pins (33). The biasing pins (33) are mounted on a structural plate (9). FIG. 5 illustrates, the flexible conductors (2) can bend only in the direction allowed by the biasing pins (33). In an exemplary embodiment, the biasing pins can be made of a structurally strong insulating material like such as epoxy resin, polyurethane or structurally reinforced plastic.
[00069] FIG. 6 illustrates a typical bus duct route to achieve universal compensation of building expansion, in accordance with another exemplary embodiment of the present disclosure. As shown in FIG. 6, the bus duct can be expected to be mounted in any of the three locations. As the building expansion unit moves, the bus duct route moves along with it. This movement transmits through the said bus duct expansion section. A relative motion is expected between the incoming bus duct (11) and the outgoing bus duct (12) along the longitudinal axis. This motion translates to the plunger action between the guide plate 936) and the expansion box (3). This motion also translates to the compression or expansion of the flexible conductor within the confines of the geometry allowed by the biasing pins (33). The biasing pins (33) can be made of a structurally strong insulating material like such as epoxy resin, polyurethane or structurally reinforced plastic. The flexible conductors (2) can bend only in the direction allowed by the biasing pins as shown in FIG. 5. These flexible conductors (2) are fastened or welded to the ends of the corresponding phases. The inter-phase barriers (37) can allow for electrical isolation between the phases. The farthest location of the flexible conductors (2) can be restricted by the inter-phase barriers (37). These barriers can be placed between the slots of the top holder plate (31) and the bottom holder plate (32). During a short-circuit condition, large amount of currents pass through the flexible. The flexible conductors are expected to experience tremendous dynamic forces in the lateral direction. These forces will then be transmitted to the biasing pins, which in turn transmit the force to the upper and lower guide plates. In worse scenarios the flexible reach their outer limits and even touches the inter-phase barriers, thus pushing the inter-phase barriers with the dynamic forces. The inter-phase barriers too are mounted on the same upper and lower mounting plates. The plates thus act as structural members and intend to absorb the loads. Minimal resultant forces are expected to be transmitted further through the mounting plates to the sides of the expansion boxes. Thus a structurally secure embodiment is presented by the invention. The motion of the plunger can be guided by the slots in the box and corresponding slots in the guide plate. These two are held together by locking pins. This motion is also guided by a plurality of guide pins that mate with the slots (91) in the structural plate of the box side plate. Stoppers (5) at the end of the guide pins limit the motion and protect the unit against structural abuse. The said stoppers (5) can be movable in nature and can thus the motion stroke of the plunger can be calibrated to meet the site requirements, lower or higher displacement. The said motion can be resisted by the springs (6) mounted concentrically over the guide pins (4) and are trapped between the support plate and outer stopper. The said spring (6) can push the assembly back into the initial position while not in use. This helps to retain the overall length of the unit before assembling with the rest of the route. Gaskets (7) lines the outer edges of the guide plate and maintain a positive pressure against the inner surface of the expansion box. Thus ingress protection is achieved.
[00070] In an embodiment, the expansion unit can include telescopic box and guide plate. The guide plate can be lined with gaskets to maintain ingress protection. In another embodiment, the expansion unit can include structural stoppers (5) and springs (6) to limit the motion and retract the assembly to the original position after releasing the load.
[00071] In an embodiment, each of the flexible conductors (2) can be provided with three insulator pins (33) in a pre-installed state such that the flexible conductor bows towards only one direction thus eliminating the requirement for providing for bi-directional clearance. This makes the expansion box compact.
[00072] In an embodiment, a plunger design can present between the expansion box and the inner guide frame. The inner guide frame which moves within the outer expansion box, is lined with a specially shaped liner. This liner maintains positive pressure with the inner surface of the expansion box. This arrangement creates ingress protection.
[00073] In an embodiment, structural stoppers and springs can be provided at the outgoing bus duct to limit the expansion or contraction. The spring works to maintain the initial arrangement of the unit. After assembly of the route the structural loads experienced beyond the end of the compression stroke are routed to the spring supports of the routes.
[00074] It should be apparent to those skilled in the art that many more modifications besides those already described are possible without departing from the inventive concepts herein. Moreover, in interpreting both the specification and the claims, all terms should be interpreted in the broadest possible manner consistent with the context. In particular, the terms “comprises” and “comprising” should be interpreted as referring to elements, components, or steps in a non-exclusive manner, indicating that the referenced elements, components, or steps may be present, or utilized, or combined with other elements, components, or steps that are not expressly referenced. Where the specification claims refers to at least one of something selected from the group consisting of A, B, C ….and N, the text should be interpreted as requiring only one element from the group, not A plus N, or B plus N, etc. The foregoing description of the specific embodiments will so fully reveal the general nature of the embodiments herein that others can, by applying current knowledge, readily modify and/or adapt for various applications such specific embodiments without departing from the generic concept, and, therefore, such adaptations and modifications should and are intended to be comprehended within the meaning and range of equivalents of the disclosed embodiments. It is to be understood that the phraseology or terminology employed herein is for the purpose of description and not of limitation. Therefore, while the embodiments herein have been described in terms of preferred embodiments, those skilled in the art will recognize that the embodiments herein can be practiced with modification within the scope of the appended claims.
[00075] While embodiments of the present disclosure have been illustrated and described, it will be clear that the disclosure is not limited to these embodiments only. Numerous modifications, changes, variations, substitutions, and equivalents will be apparent to those skilled in the art, without departing from the scope of the disclosure, as described in the claims.
[00076] In the description of the present specification, reference to the term "one embodiment," "an embodiments", "an example", "an instance", or "some examples" and the description is meant in connection with the embodiment or example described The particular feature, structure, material, or characteristic included in the present invention, at least one embodiment or example. In the present specification, the term of the above schematic representation is not necessarily for the same embodiment or example. Furthermore, the particular features structures, materials, or characteristics described in any one or more embodiments or examples in proper manner. Moreover, those skilled in the art can be described in the specification of different embodiments or examples are joined and combinations thereof.
[00077] All of the features disclosed in this specification (including any accompanying claims, abstract and drawings), and/or all of the steps of any method or process so disclosed, may be combined in any combination, except combinations where at least some of such features and/or steps are mutually exclusive.
[00078] Each feature disclosed in this specification (including any accompanying claims, abstract and drawings) may be replaced by alternative features serving the same, equivalent or similar purpose, unless expressly stated otherwise. Thus, unless expressly stated otherwise, each feature disclosed is one example only of a generic series of equivalent or similar features.
[00079] The invention is not restricted to the details of the foregoing embodiment(s). The invention extends to any novel one, or any novel combination, of the features disclosed in this specification (including any accompanying claims, abstract and drawings), or to any novel one, or any novel combination, of the steps of any method or process so disclosed.
[00080] While the foregoing describes various embodiments of the invention, other and further embodiments of the invention may be devised without departing from the basic scope thereof. The scope of the invention is determined by the claims that follow. The invention is not limited to the described embodiments, versions or examples, which are included to enable a person having ordinary skill in the art to make and use the invention when combined with information and knowledge available to the person having ordinary skill in the art.

ADVANTAGES OF THE INVENTION
[00081] The present disclosure provides an improved compensation mechanism for building expansion.
[00082] The present disclosure provides a busway building expansion section for the purpose of ingress protection and absorbing the expansion.
[00083] The present disclosure provides a means of compensating the difference between the thermal elongations of dissimilar materials used in busways.
[00084] The present disclosure provides a busbar expansion unit or busbar expansion joint for ingress protection.
[00085] The present invention provides a busbar expansion unit or busbar expansion joint to withstand high short circuit levels.
[00086] The present disclosure provides a busbar expansion unit or busbar expansion joint with structural stoppers and springs to limit the motion and retract the assembly to the original position after releasing the load.
[00087] The present disclosure provides structural supports within the busbar expansion unit to take care of the dynamic forces created during a short circuit.