FORM 2
The Patents Act 1970
(39 of 1970)
&
The Patent Rules 2003
COMPLETE SPECIFICATION
(See Section 10 and rule 13)
TITLE OF THE INVENTION:
LINK WORK ASSEMBLY FOR SWITCH BOARD


APPLICANT:
LARSEN & TOUBRO LIMITED
L&T House, Ballard Estate, P.O. Box No. 278,
Mumbai- 400 001, Maharashtra. INDIA.
PREAMBLE OF THE DESCRIPTION:

THE FOLLOWING SPECIFICATION PARTICULARLY DESCRIBES THE
INVENTION AND THE MANNER IN WHICH IT IS TO BE PERFORMED


A) TECHNICAL FIELD
[0001] The present invention generally relates to switching devices and particularly to conductors in switchboards and the like. The present invention more particularly relates to link assembly for circuit breakers within a switchboard.
B) BACKGROUND OF THE INVENTION
[0002] In a typical electrical panel, such as a switchboard or switchgear, plurality of bus bar assemblies are arranged in parallel with sufficient spacing between them. Each bus bar assembly has several conductors arranged in a stack. Each conductor is separated from one another by an insulating/conducting spacer. A switchboard may have various control and protection equipments, like circuit breakers, to protect the equipments down the line. Such circuit breakers are connected to the bus-bars thorough sets of conductors, generally called as linkwork. The conductor which is usually a bar made up of copper or aluminum is called as a link. The links are widely used almost in all connections made in a low voltage switchboard. The links have several profiles which include bending at 45 and 90 degrees. Several links are stacked together to form a link assembly so that a gap is provided between two adjacent links for cooling. Generally spacers are used to fill the gap between the adjacent links. Assembling these spacers is a tedious task as there are several joints for a single link and many spacers are fastened at one point. One has to hold all the spacers at one place together to insert a fastener through the holes in the spacer and that in the links. Then he has to tighten the fastener to secure the links and the spacers together. Thus
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the assembly task becomes difficult due to lack of access and available space in a switch board.
[0003] Currently all the links are first assembled and then all spacers are held by hand. Afterwards a bolt is inserted into the holes to hold and tighten the spacers and the links. The major disadvantage with the above assembling method is that it consumes too much time and requires more than one person or highly skilled persons to assemble the links in a panel. Most of the time spacers may fall from the switchboard assembly due to improper alignment.
[0004] Hence there is a need to simplify the assembly of the spacers and links in a link assembly and enable even a semi skilled or unskilled to assemble the links easily and efficiently.
[0005] The abovementioned shortcomings, disadvantages and problems are addressed herein and which will be understood by reading and studying the following specification.
C) OBJECTS OF THE INVENTION
[0006] The primary object of the present invention is to develop link work assembly for switchboard in a low voltage air circuit breakers so that the assembly time is reduced and assembly process is simplified.
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[0007] Another object of the present invention is to develop link work assembly for circuit breaker in a switchboard so that even a semi skilled or unskilled person may assemble the link assembly easily and efficiently.
[0008] These and other objects and advantages of the present invention will become readily apparent from the following detailed description taken in conjunction with the accompanying drawings.
D) SUMMARY OF THE INVENTION
[0009] The various embodiments of the invention provide a link work assembly for a switch board and its assembly method to simplify the assembly process and to reduce the assembly time. Even semi skilled or unskilled personnel may assembly the link work assembly easily without requiring additional manpower thereby reducing the manpower and the man-hours for an assembly process.
[0010] According to one embodiment of the present invention, the link work assembly has plurality of links stacked together in such a manner that a gap is provided between two adjacent links for cooling. The plurailities of the links are supported at periodic intervals using an insulating link support. A spacer with preset profile is provided between the links so that the links and the spacers are fastened using a tool. The spacer is punched with a unique pattern of oblong holes and a central hole. The spacer has oblong holes at both the sides with the holes having opening extended up to the sides of the spacers. The spacers have a central hole at the middle. The oblong hole is extended up to the edge, thereby making the entry of any
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tool/holding means from the side of the spacer possible. Each link has a pair of small holes at both edges and a central hole is provided between the pair of small holes. The tool has two arms coupled to a support which is driven by a shaft. The arms of the tool are inserted into the pair of small holes provided at the links, which are stacked together, to hold all the links together. Then the spacers are inserted between the adjacent links so that the oblong holes are made to contact the tool and the central holes in the links are aligned with the central holes in spacers. Then a fastener is inserted into the central holes to secure the links and the spacer together. The fastener includes bolt, screw etc.
[0011] According to another embodiment a method is provided for assembling the links using a spacer and a tool. According to the method, pluralities of the links are supported at periodic intervals using an insulating link support. Then the two arms of the tool are inserted respectively and simultaneously into the pair of small holes provided at the links that are stacked together, to hold all the links together temporarily. Then the spacers with preset profile are inserted between the adjacent links so that the oblong holes of the spacers are made to contact the tool and the central holes in the links are aligned with the central holes in spacers. The spacers are inserted in to the gaps between the links such that the inserted arms of the tool act as a guide for the oblong hole of the spacers. Then a fastener is inserted into the central holes to secure the links and the spacer together. The fastener includes bolt, screw etc. After the fastening of the links and the spacers, the tool is removed.
[0012] The unique pattern of the holes in the present invention helps in easy alignment of the spacers with respect to the holes in the links. It also avoids the
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likelihood of the spacers from being fallen off from their intended location during the course of the assembly. It reduces the assembly time and simplifies the assembly process. Even a semi skilled or unskilled personnel may assemble the links and the spacers together easily and efficiently without requiring any additional manpower thereby reducing the manpower and the man hours needed for assembling the link assembly.
E) BRIEF DESCRIPTION OF THE DRAWINGS
[0013] The other objects, features and advantages will occur to those skilled in the art from the following description of the embodiments and the accompanying drawings in which:
[0014] FIG. I shows the front view of the link in a link assembly according to one embodiment of the present invention.
[0015] FIG. 2 shows the front perspective view of the spacer in a link assembly according to one embodiment of the present invention.
[0016] FIG. 3 shows the perspective view of the link assembly according to one embodiment of the present invention.
[0017] FIG. 4 shows the side view of the link assembly according to one embodiment of the present invention, during the assembly process.
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[0018] FIG. 5 shows a side perspective view of the link assembly according to one embodiment of the present invention.
[0019] FIG. 6 shows a perspective view of the tool used in the link work assembly according to one embodiment of the present invention.
[0020] FIG. 7 illustrates a flow chart explaining the assembly method of link work assembly according to one embodiment of the present invention.
[0021] Although specific features of the present invention are shown in some drawings and not in others. This is done for convenience only as each feature may be combined with any or all of the other features in accordance with the present invention.
F) DETAILED DESCRIPTION OF THE INVENTION
[0022] In the following detailed description, reference is made to the accompanying drawings that form a part hereof, and in which the specific embodiments that may be practiced is shown by way of illustration. These embodiments are described in sufficient detail to enable those skilled in the art to practice the embodiments and it is to be understood that the logical, mechanical and other changes may be made without departing from the scope of the embodiments. The following detailed description is therefore not to be taken in a limiting sense.
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[0023] According to one embodiment of the present invention, the link work assembly has plurality of links stacked together in such a manner that a gap is provided between two adjacent links for cooling. The pluralities of the links are supported at periodic intervals using an insulating link support. A spacer with preset profile is provided between the links so that the links and the spacers are fastened using a tool. The spacer is punched with a unique pattern of oblong holes and a central hole. The spacer has oblong holes at both the sides with the holes having an open end at the sides of the spacers. The spacers have a central hole at the middle. The oblong hole is extended up to the edge, thereby making the entry of any tool/holding means from the side of the spacer possible. Each link has a pair of small holes at both edges and a central hole is provided between the pair of small holes. The tool has two arm scoupled to a support which is driven by a shaft. the arms of the tool are inserted into the pair of small holes provided at the links, which are stacked together, to hold all the links together. Then the spacers are inserted between the adjacent links so that the oblong holes are made to contact the tool and the central holes in the links are aligned with the central holes in spacers. Then a fastener is inserted into the central holes to secure the links and the spacer together. The fastener includes bolt, screw etc.
[0024] According to another embodiment a method is provided for assembling the links using a spacer and a tool. According to the method, pluralities of the links are supported at periodic intervals using an insulating link support. Then the two arms of the tool are inserted respectively and simultaneously into the pair of small holes provided at the links that are stacked together, to hold all the links together temporarily. Then the spacers with preset profile are inserted between the adjacent
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links so that the oblong holes of the spacers are made to contact the tool and the central holes in the links are aligned with the central holes in spacers. The spacers are inserted in to the gaps between the links such that the arms of the tool act as a guide for the oblong hole of the spacers. Then a fastener is inserted into the central holes to secure the links and the spacer together. The fastener includes bolt screw etc. after the fastening of the links and the spacers, the tool is removed.
[0025] The unique pattern of the holes in the present invention helps in easy alignment of the spacers with respect to the holes in the links. It also avoids the likelihood of the spacers from being fallen off from their intended location during the course of the assembly. It reduces the assembly time and simplifies the assembly process. Even semi skilled or unskilled personnel may assemble the links and the spacers together easily and efficiently without requiring any additional manpower thereby reducing the manpower and the man hours needed for assembling the link assembly.
[0026] FIG. 1 shows the front view of the link in a link assembly according to one embodiment of the present invention. With respect to FIG. I, link 10 is generally a conductor bar made of copper or aluminum. Links 10 have several profiles which include bends at 45 and 90 degrees. Several links 10 are stacked together to form a link assembly so that a gap is provided between two adjacent links 10 for cooling. The spacers are provided in the gap between adjacent links 10. The central portion of link 10 has a pair of small circular holes provided at both side edges. Central circular hole 12 is formed between the two sets of smaller holes 14 to receive a tool to hold the links together temporarily during an assembly process.
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[0027] FIG. 2 shows the front perspective view of the spacer in a link assembly according to one embodiment of the present invention. With respect to FIG. 2, spacer 20 is a conducting material and helps in thermal and electrical equalization amongst the links. Spacer 20 is used to fill the gap between the links that are stacked together. Spacer 20 has two sets of oblong holes 22 provided at the ends and large central hole 24 at the center. Oblong holes 22 have an opening at the ends thereby making the entry of any tool/holding means from the side of spacer 22 possible. The unique pattern of holes on the links and spacers 20 enables the too! to be inserted and holds spacers 20 in place. It ensures ease of assembly, especially in case of higher number of links per set, where the number of spacers also goes up.
[0028] FIG. 3 shows the perspective view of the link assembly according to one embodiment of the present invention. With respective to FIG.3, pluralities of links 10 are stacked together and mounted on insulating support 30 at periodic intervals. Link 10 is a conductor which is usually a bar made of copper or aluminum. Links 10 are assembled and placed one above the other in their intended location. Links 10 includes profiles with the bends at 45 and 90 degrees etc. Links 10 are stacked together so that a gap is provided between the adjacent links for cooling. The size of the gap is equal to thickness of link 10. Spacer 20 which is a conducting material is used to fill the gap between links 10. Link support 30 carries dedicated holes 32 for mounting the link assembly.
[0029] FIG. 4 shows the side view of the link assembly according to present invention, during the assembly process. With respect to FIG.4,
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pluralities of links 10 are stacked together and mounted on a link support so that gap 40 is formed between the adjacent links 10 for cooling. Spacer 20 is provided in gap 40 and fastened with links 10. After the stacking of links 10, in their intended location, arms 44 of a tool are inserted into the smaller set of holes in link 10 to temporarily support and hold links 10 together. Then spacers 20 are inserted into gaps 40 between the links 10 from the sides, such that arms 44 of the tool act as a guide for oblong slot 22 of spacers 20. Once spacers 20 are located in place, bolt 30 is inserted through the bigger holes provided in links 10 and in spacers 20, to secure links 10 and spacers 20 together. Finally the tool is removed after the assembly process.
[0030] FIG. 5 shows a side perspective view of the link assembly according to one embodiment of the present invention. With respect to FIG. 5, the links are stacked together to form a gap between the links. Spacer 20 is inserted between the adjacent links and is secured together using a tool and a fastener as explained above.
[0031] FIG. 6 shows a perspective view of tool 60 used in the link work assembly according to one embodiment of the present invention. With respect to FIG.6, tool 60 has two arms 44 connected to a support coupled to a shaft or rod 42. By driving the rod or shaft 42, two arms 44 of tool 60 are inserted simultaneously into the smaller set of holes in the links to hold the links together temporarily during the assembly process. The Arms 44 of tool 60 act as a guide for oblong slot 22 of spacers 20 when the spacers are inserted in to the gaps between the links.
[0032] FIG. 7 illustrates a flow chart explaining the assembly method of link work assembly according to one embodiment of the present invention. With respect to FIG.
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7, pluralities of the links are stacked together and supported at periodic intervals using an insulating link support (70). Then the two arms of the tool are inserted respectively and simultaneously into the pair of small holes provided at the links that are stacked together, to hold all the links together temporarily (72). Then the spacers with preset profile are inserted between the adjacent links so that the oblong holes of the spacers are made to contact the tool and the central holes in the links are aligned with the central holes in spacers. The spacers are inserted in to the gaps between the links such that the shaft or rod of the tool acts as a guide for the oblong hole of the spacers (74). Then a fastener is inserted into the central holes to secure the links and the spacer together (76). The fastener includes bolt, screw etc. After the fastening of the links and the spacers, the tool is removed.
[0033] The assembling process is simplified due to the unique and novel combination of the central and oblong holes, punched onto the spacers and the corresponding set of holes on the links. It ensures easy alignment of the spacers with respect to the holes for bolting the spacers with the links. It also avoids the likelihood of the spacers being fallen-off from their intended locations during the course of the assembly. The unique pattern of holes on the links and spacers enables the tool to be inserted and hold the spacers in place. Thus the assembly process is simplified, even when more number of links and spacers are assembled.
G) ADVANTAGES OF THE INVENTION
[0034] The unique pattern of the holes in the present invention helps in easy alignment of the spacers with respect to the holes in the links, ft also avoids the
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likelihood of the spacers from being fallen off from their intended locations during the course of the assembly. It reduces the assembly time and simplifies the assembly process. Even semi skilled or unskilled personnel may assemble the links and the spacers together easily and efficiently without requiring any additional manpower thereby reducing the manpower and the man hours needed for assembling the link assembly.
[0035] Although the invention is described with various specific embodiments, it will be obvious for a person skilled in the art to practice the invention with modifications. However, all such modifications are deemed to be within the scope of the claims.
[0036] It is also to be understood that the following claims are intended to cover all of the generic and specific features of the present invention described herein and all the statements of the scope of the invention which as a matter of language might be said to fall there between.
Date: 04th February, 2009. RAKESH PRABHU
Place: Bangalore. Patent Agent
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CLAIMS
What is claimed is:
1. A link work assembly for switch board, the assembly comprising:
A link support;
pluralities of links stacked together and supported on the link support; and
spacer with preset profile inserted into a gap formed between the adjacent
links;
wherein the spacer is punched with a unique set of holes so that the spacer is
inserted easily into the gap formed between the adjacent links and fastened
with the links.
2. The assembly according to claim 1, wherein the spacer is formed with a pair of oblong holes at the two side edges and a central hole at the middle portion.
3. The assembly according to claim 2, wherein the oblong holes has an opening extended up to the edge of the spacer.
4. The assembly according to claim I, wherein the links has a central hole and two set of smaller holes so that the central hole is formed between the set of smaller holes to receive a fastener to secure the links and the spacer together.
5. The assembly according to claim 1, wherein the links has the set of smaller holes to receive a tool to hold and support the pluralities of the links stacked together temporarily.
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6. The assembly according to claim 1, wherein the spacer is inserted into the gap between the adjacent links from sideways after holding the links together with the tool so that the oblong holes are in contact with the tool and the tool act as a guide.
7. The assembly according to claim 1 further comprises a fastener inserted into the central holes provided in the links and in the spacers to secure the links and the spacers together.
8. The assembly according to claim 5, wherein the tool has a pair of arms inserted into the smaller holes in the links to hold the links together temporarily during the assembly process.
Dated this 04m of February, 2009
Rakesh Prabhu,
Patent Agent, ALMT Legal,
No.2, Lavelle Road, Bangalore-560 001, INDIA
To,
The Controller of Patents,
The Patent office, Mumbai
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