Claims:WE CLAIM:

1. A joint pack assembly to connect at least two busway units, wherein said joint pack means comprising:
plurality of insulating phase barrier, each of which holds set of splice plates facing each other in an assembled position;
plurality of compression spring means positioned between said set of splice plates;
Wherein, inner diameter of said compression spring is bigger than size of at least a bolt means and outer diameter smaller than the clearance between at least two busbars of said busway units;
Wherein, natural length of said compression spring is higher than the clearance between said set of splice plates, such that said compression spring means exerts an opposing force on said set of splice plates.

2. The joint pack assembly as claimed in claim 1, wherein said splice plates made of a conducting material.

3. The joint pack assembly as claimed in claim 1, wherein said phase barriers made of an electrical insulator.

4. The joint pack assembly as claimed in claim 1, wherein said splice plates and said phase barriers are mounted over said bolt means.

5. The joint pack assembly as claimed in claims 1 to 3, wherein said phase barriers and splice plates lie between at least two cover plates and said cover plates hold at least a spring washer means.

6. The joint pack assembly as claimed in any of claims 1 to 5, is held together over the axis of a bolt surface using a nut means at the end.
7. The joint pack assembly as claimed in claim 1, wherein each of said splice plate is chamfered at edges.

8. The joint pack assembly as claimed in claim 1, wherein each of said phase barrier includes a recess that binds said splice plate enough that a mating surface of said splice plate extends beyond said recess.

Dated this 29th day of March 2019

Abhishek Sen
IN/PA Reg No: 980
Of S. MAJUMDAR & CO.
(Applicant’s Agent)
, Description:F O R M 2

THE PATENTS ACT, 1970
(39 of 1970)
&
The Patents Rules, 2003
COMPLETE SPECIFICATION
(See section 10; rule 13)

1. Title of the invention –

A JOINT PACK ASSEMBLY FOR JOINING BUSWAY UNITS

2. Applicant(s)

(a) NAME : LARSEN & TOUBRO LIMITED

(b) NATIONALITY: An Indian Company.

(c) ADDRESS: L & T House, Ballard Estate, P.O. Box: 278,
Mumbai 400 001, State of Maharashtra, India

3. PREAMBLE TO THE DESCRIPTION

The following specification particularly describes the invention and the manner in which it is to be performed:

TECHNICAL FIELD

[001] The present subject matter described herein, in general, relates to busways or busduct. More particularly, the invention relates to means for joining busducts or busways.

BACKGROUND

[002] There are several different techniques to join two sections of a busway. Most of these methods use an array of conductive plates housed within insulator plates with space within to accommodate the busbars of the busway sections for creating an electrical joint. These designs require making holes or embossed features in the conductive plates or even require the plates to be bent. These additional features make the manufacturing process complex and expensive. Furthermore, the designs are unable to provide fully aligned splice plates for making smooth insertion of the busway units.

[003] Reference is made to a prior art US4627680 which describes a detachable joint assembly. The recess in the insulator holds the splice plates, the clearance between the plates, the tapered edges of the insulator plates, and the recess facilitate insertion of the joint assembly into position without undue interference. The subassembly of the insulator and splice plate thus remains loose until the busbars are inserted making the process of insertion of the busbar uneasy for the user.

[004] Reference is further made to a prior art US3180924 which describes a means to achieve connection between two busbars using spring loaded bridging contacts. These contacts are essentially plates of Copper or Aluminium which are bent at the ends, the bends are tucked away inside recesses making a cozy entry chamfer for the busbars to enter. While the splice plates are tightly aligned before making the assembly, they are housed within an insulator case making the assembly bulky and certainly requires bending of the splice plates.

[005] Reference is made to EP0815626B1, which describes a joint pack design that uses splice plates bent inwards towards each other together with a bush arrangement to hold them together. The design allows for an easy ingress of the busbars at the same time retaining the necessary entry clearance to avoid fouling. The design too however requires bending of the splice plates.

[006] However, the problem with the existing joint pack design is that splice plates require bending, complex shapes otherwise they can come loose and cause fouling of busbars and joint pack during insertion.

[007] Therefore, there exists a dire need for an improved joint pack design for connecting electrical joins of busways or busducts without requiring bending or complexity in shape.

SUMMARY OF THE INVENTION

[008] The following presents a simplified summary of the invention in order to provide a basic understanding of some aspects of the invention. This summary is not an extensive overview of the present invention. It is not intended to identify the key/critical elements of the invention or to delineate the scope of the invention. Its sole purpose is to present some concept of the invention in a simplified form as a prelude to a more detailed description of the invention presented later.

[009] Another objective of the present invention is to provide a joint pack means having a compression spring between the equipotential splice plates.

[0010] Accordingly, in one aspect, in one implementation, the present invention provides a joint pack assembly to connect at least two busway units, wherein said joint pack means comprising:
plurality of insulating phase barrier, each of which holds set of splice plates facing each other in an assembled position;
plurality of compression spring means positioned between said set of splice plates;
Wherein, inner diameter of said compression spring is bigger than size of at least a bolt means and outer diameter smaller than the clearance between at least two busbars of said busway units;
Wherein, length of said compression spring is higher than the clearance between said set of splice plates, such that said compression spring means exerts an opposing force on said set of splice plates.

[0011] Other aspects, advantages, and salient features of the invention will become apparent to those skilled in the art from the following detailed description, which, taken in conjunction with the annexed drawings, discloses exemplary embodiments of the invention.

BRIEF DESCRIPTION OF THE ACCOMPANYING DRAWINGS

The above and other aspects, features, and advantages of certain exemplary embodiments of the present invention will be more apparent from the following description taken in conjunction with the accompanying drawings in which:

[0012] Figure 1 illustrates a view of joint pack inserted into the busway units, according to one implementation of the present invention.

[0013] Figure 2 shows a view of the joint pack with compression springs in a loose position, according to one implementation of the present invention.

[0014] Figure 3 illustrates a view of the joint pack without springs in the pre-engagement position, according to one implementation of the present invention.

[0015] Figure 4 illustrates another view of the joint pack without springs in the pre-engagement position, according to one implementation of the present invention.

[0016] Persons skilled in the art will appreciate that elements in the figures are illustrated for simplicity and clarity and may have not been drawn to scale. For example, the dimensions of some of the elements in the figure may be exaggerated relative to other elements to help to improve understanding of various exemplary embodiments of the present disclosure. Throughout the drawings, it should be noted that like reference numbers are used to depict the same or similar elements, features, and structures.

DETAILED DESCRIPTION OF THE PRESENT INVENTION

[0017] The following description with reference to the accompanying drawings is provided to assist in a comprehensive understanding of exemplary embodiments of the invention. It includes various specific details to assist in that understanding but these are to be regarded as merely exemplary.

[0018] Accordingly, those of ordinary skill in the art will recognize that various changes and modifications of the embodiments described herein can be made without departing from the scope of the invention. In addition, descriptions of well-known functions and constructions are omitted for clarity and conciseness.

[0019] The terms and words used in the following description and claims are not limited to the bibliographical meanings, but, are merely used by the inventor to enable a clear and consistent understanding of the invention. Accordingly, it should be apparent to those skilled in the art that the following description of exemplary embodiments of the present invention are provided for illustration purpose only and not for the purpose of limiting the invention as defined by the appended claims and their equivalents.

[0020] It is to be understood that the singular forms “a,” “an,” and “the” include plural referents unless the context clearly dictates otherwise.

[0021] By the term “substantially” it is meant that the recited characteristic, parameter, or value need not be achieved exactly, but that deviations or variations, including for example, tolerances, measurement error, measurement accuracy limitations and other factors known to those of skill in the art, may occur in amounts that do not preclude the effect the characteristic was intended to provide.

[0022] Features that are described and/or illustrated with respect to one embodiment may be used in the same way or in a similar way in one or more other embodiments and/or in combination with or instead of the features of the other embodiments.

[0023] It should be emphasized that the term “comprises/comprising” when used in this specification is taken to specify the presence of stated features, integers, steps or components but does not preclude the presence or addition of one or more other features, integers, steps, components or groups thereof.

[0024] The present invention discloses a means to connect two busway units using a joint pack such that the joint pack does not foul with the busbars of the units during insertion.

[0025] It is also to be understood that the term “means” is used in the specification to indicate an apparatus, unit, component and the like.

[0026] In one implementation, reference is made to figure 1 which shows the intended assembly, the busway units are electrically engaged with the joint pack.

[0027] In one implementation, reference is made to figure-2 which shows a loose joint pack. The splice plates can be held inside the recess of the phase barrier and the phase barriers can be equally spaced from one another.

[0028] In one implementation, reference is made to figure-3 which shows the joint pack with misaligned phase barriers without any springs to align them.

[0029] In one implementation, reference is made to figure-4 which shows the joint pack with misaligned phase barriers and further splice plates that have come loose from the recess of the phase barriers, the pitch between the phase barriers can be seen awry. d1 ? d2 ? d3.

[0030] According to the figures 1-4, the various components of the assembly are as follows:
1. Busway
2. Joint pack
3. Nut
4. Washer
5. Cover plate
6. Joint case
7. Busbar
8. Phase barrier
81 Recess
9. Splice plate
91 Chamfer in splice plate
10. Bolt
101 Bolt head
11. Compression spring

[0031] In one implementation, the joint pack means is having a compression spring of an inner diameter bigger than the size of the bolt and an outer diameter smaller than the clearance between the busbars of two facing busways to be inserted. The natural length of the compression spring is longer than the clearance between adjacent splice plates post assembly such that it always exerts an opposing force on the splice plates.

[0032] In the implementation, the joint pack splice plates maintain flexibility to move during insertion thus reducing the amount of inserting force required. The joint pack can be made of multiple insulating phase barrier each of which holds splice plates made of a conducting material that may include but not limited to Copper or Aluminium. These splice plates and phase barriers can be mounted over a sleeved bolt. The set of phase barriers and splice plates may lie between two cover plates. The cover plates in turn hold Bellville washers. The bolt passes through holes provided in each of these elements such that the pieces are concentric and aligned. The assembly is held together over the axis of the bolt surface using a nut at the end such that all the elements mentioned above are held between the head of the bolt and the nut.

[0033] In the implementation, the compression spring may be placed between each of the sets of splice plate and insulator, the springs are also mounted over the bolt’s long axis such that they are constrained between the set of splice plates and phase barriers and over the bolt.

[0034] In the implementation, the natural length of the compression spring is higher than the clearance between two splice plates facing each other in an assembled position such that the compression spring always maintains tension. This tension pushes the splice plates into the phase barriers and further maintains equidistant pitch between each pair of barriers. This distance varies with the tightening of the nut over the bolt.

[0035] In the implementation, each splice plate is chamfered at the edges and a recess in the phase barrier binds the plate enough that the mating surface of the plate extends beyond the recess. This facilitates an entry chamfer for smooth ingress of the busbars.

[0036] In the implementation, the compression spring can be of any material that can withstand the elevated operating temperatures of the busway joint pack. Since the adjacent splice plates are equipotential, the springs are not expected to carry any current although they are held in contact tightly.

[0037] Some of the noteworthy features of the present invention, are mentioned below:
1) Use of a compression spring between the equipotential splice plates of a busway joint pack.
2) A compression spring having an inner diameter bigger than the size of the bolt and an outer diameter smaller than the clearance between the busbars of two facing busways to be inserted.
3) The natural length of the compression spring which is always longer than the clearance between adjacent splice plates post assembly such that it always exerts an opposing force on the splice plates.

[0038] Although a joint pack assembly for joining busway units have been described in language specific to structural features and/or methods, it is to be understood that the embodiments disclosed in the above section are not necessarily limited to the specific features or methods or devices described. Rather, the specific features are disclosed as examples of implementations of the joint pack assembly for joining busway units.