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:
COMPRESSION MOULD FOR CONDUCTORS IN ELECTRICAL ASSEMBLIES
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 electrical assemblies, and particularly to molding of conductors in electrical assemblies. The present invention more particularly relates to compression moulding process for components in electrical assemblies.
B) BACKGROUND OF THE INVENTION
[0002] In most of the electrical products, the compression moulded thermoset parts are being widely used primarily for insulation purposes. Most of the switchgear or other products consist of assemblies where the conducting parts are fastened to the insulating housing with the help of hardware. In other words, the conducting parts are sandwiched between two insulation parts. However if multiple - number of conducting parts or connections have to be made, it becomes very complex to insulate these parts from each other. Additionally geometries of insulating parts become very complicated. This also poses a question on the reliability of these parts and their performance under abnormal conditions like short circuit. It is also likely that the entire assembly becomes bulky and uncompetitive from cost point of view. Also the chances of insulation failure increase when there are overlapping conducting parts.
[0003] In conventional method, the conducting parts or inserts are placed on the tool along with the charge and the tool is closed so that the material flows under certain conditions of temperature and pressure and completely fills the parts geometry. Although the conventional compression moulding process offers the moulding of conducting parts directly with the housing, it is not possible to mould the parts when there is an overlap of the connections. This is because the copper parts get softened under conditions

of pressure and temperature and the gap between two parts is bridged due to bending of the parts on closing of the tool.
[0004] Typically inserts are made of brass arid the cavities holding this inserts are in close tolerances of the order of 0.1mm or even less to avoid the excess material or flash. However, for application in electrical industry, the copper is considered as the material for conducting parts. The molding of the copper parts by this method leads to deformation of the copper parts and could pose problems while ejection of the components as gap between copper inserts and the cavity is reduced due to expansion of copper at 150 C.
[0005] None of the prior art discloses a method for moulding of
multiple conductor parts in electrical assemblies. Hence there is a need to
develop an improved, more compact and high performance solutions for
molding multiple conductor parts.
[0006] The above mentioned shortcomings, disadvantages and problems are addressed herein and which will be understood by reading and studying the following specification.
C) OBJECT OF THE INVENTION
[0007] The primary object of the present invention is to develop an improved method for compression moulding of conductors for electrical assemblies.
[0008] Another object of the present invention is to develop an improved method for molding of conductors which provides a single moulded component instead of multiple parts.

[0009] Another object of the present invention is to develop an improved method for molding of conductors to achieve conductors having high with-standing properties under short circuit condition.
[0010] Yet another object of the present invention is to develop an improved molding method which is compact enough and easy to use and assemble.
[0011] Yet another object of the present invention is to develop an improved molding method to provide conductors with higher insulation strength.
[0012] 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
[0013] The above mentioned shortcomings, disadvantages and problems are addressed herein and which will be understood by reading and studying the following specification.
[0014] The various embodiments of the present invention provide a method for compression molding conductor parts in electrical assemblies. The present invention relates to a process of moulding which offers the option of moulding multiple conducting parts with close tolerances and spacing and providing higher insulation strength by maintaining the desired spacing between the two parts. A compression mould for components in electrical assemblies comprises three parts namely inserts or the conducting

parts, the pre-moulded parts and the charge or fresh material for moulding the component. The first insert is primarily placed in the moulding block. The pre-moulded insert is then placed over the moulding block and the second insert is placed over the first insert and the pre-moulded inserts. Finally a charge is placed over the first insert , second insert and the pre-moulded insert.
[0015] According to an embodiment of the present invention, pre-
moulded parts of the same raw material are used to insulate the two conducting parts. The pre-moulded part has already undergone the conditions of temperature and pressure and has been cured while the properties of the pre-moulded part remains unaltered during remolding. The part geometry is designed in such a way to totally insulate the two parts and also be used for holding in the cavity.
[0016] According to one embodiment of the present invention, the fresh material flows into the minute gaps between the parts on moulding and cures along with the gaps making the component completely sturdy. Thus a compact one piece component with multiple conductors can be moulded together to give good performance. Typically sheet moulding composites (SMC) is used for electrical insulation due to its various properties like higher insulation resistance, tracking index and performance at higher temperature and inertness to most weathering conditions. The process as mentioned above can be used for SMC as well as other materials of similar type like DMC or BMC.
E) BRIEF DESCRIPTION OF THE DRAWINGS
[0017] The other objects, features and advantages will occur to those
skilled in the art from the following description of the preferred embodiment and the accompanying drawings in which:

[0018] FIG. 1 illustrates a schematic representation of different views
of the component according to an embodiment of the present invention.
[0019] FIG. 2 illustrates various sectional view of the component
according to an embodiment of the present invention.
[0020] FIG. 3 illustrates the conducting parts, pre-moulded parts and the tool cavity for moulding the component according to an embodiment of the present invention.
[0021] FIG. 4 illustrates the steps involved in inserting conducting parts into the tool cavity according to an embodiment of the present invention.
[0022] 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
[0023] 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.
[0024] The various embodiments of the present invention provide a compression mould for molding conductor parts in electrical assemblies. The present invention relates to a process of moulding which offers the option of moulding multiple conducting parts with close tolerances and spacing and further providing higher insulation strength by maintaining the desired spacing between the two parts. The mould for conductors for electrical assemblies comprises three parts namely inserts or the conducting parts, pre-moulded parts and the charge or fresh material for moulding the component. The first insert is primarily placed in the moulding block. The pre-moulded insert in placed over it and the second insert is then placed over the frrst and pre-moulded inserts. Finally the charge is placed over all the said inserts.
[0025] FIG. 1 illustrates a schematic representation of the different views of the component according to an embodiment of the present invention. FIG. la illustrates the front view of the compression mould for molding conductor parts. FIG. lb illustrates the side view of the compression mould. FIG. lc illustrates the bottom view of the compression mould. FIG. Id illustrates the top view of the compression mould. FIG. le illustrates the isometric view of the compression mould. A conducting insert 2 is inserted into the molding component 5. Then the pre-molded insert 4 is inserted over the conducting insert 2. The conducting insert 3 is inserted over the conducting insert 2 and the pre-molded insert 4 as shown in FIG. 1.
[0026] FIG. 2 illustrates a sectional view of the compression mould according to an embodiment of the present invention. First, a conducting insert 2 is inserted and then the pre-molded insert 4 is arranged on top of the conducting insert. The conducting insert 3 is inserted then over these two inserts 2, 4. A charge 1 or a fresh material for moulding the compression is

then placed over the inserts as shown in FIG. 2a, FIG. 2b and FIG. 2c. An insulating material is placed between the two conducting parts 2 and 3 to prevent the bridging of the gap between the conducting parts 2 and 3. A pre-moulded part 4 of the same raw material is used to insulate the two conducting parts 2 and 3. Since the pre-moulded part 4 is already undergone the conditions of temperature and pressure and has cured, its properties remain unaltered while remolding. The pre-molded part 4 geometry is designed in such a way that the pre-molded part 4 totally insulates the two conducting parts 2 and 3.
[0027] FIG. 3 illustrates the conducting parts, pre-moulded part and the tool cavity for moulding the component according to an embodiment of the present invention. FIG. 3a shows the first conducting insert 2. The second conducting insert 3 is as shown in FIG. 3b and the pre-molded insert is as shown in FIG. 3c. FIG. 3d illustrates a tool cavity. The process for molding pre-mold insert includes heating the tool to a temperature of around 150C. The insert 2, 4 and the charge are then placed on the tool as per the calculated weight. Further, the tool is covered and kept under certain conditions of temperature and pressure referred as the curing time. As the pre-molded parts is of the same raw material and the pre-molded part is already undergone the conditions of temperature and pressure and has cured, its properties remain unaltered while remolding.
[0028] FIG. 4 illustrates the steps involved for inserting conducting parts into the tool cavity according to an embodiment of the present invention. The conducting insert 2 is inserted first as shown in FIG. 4a and FIG. 4b. Then the pre-molded insert 4 is inserted as shown in FIG. 4c and conducting insert 3 is inserted over these two inserts as shown in FIG. 4d. A charge 1 or fresh material for moulding the component is then placed over the inserts as shown in FIG. 4e. The cover 6 is closed on the molding component 5 as shown in FIG. 4f. On molding, the charge 1 or fresh material

flows in the minute gaps between the inserted parts (2, 3 and 4) and cures along with it making the mould completely sturdy. Thus a compact one piece component with multiple conductors is moulded together to give good performance. Typically sheet moulding composites (SMC) is used for electrical insulation due to its various properties like higher insulation resistance, tracking index and performance at higher temperature and inertness to most weathering conditions. The present invention can be used for this material as well as other materials of similar type like DMC or BMC.
G) ADVANTAGES OF THE INVENTION
[0029] A method of the present invention provides a single component instead of multiple parts. The component compact enough, easy to handle in assembly line as only one component is to be handled and is highly reliable.
[0030] The material of the present invention is used for re-molded parts i.e. insulation. This helps to retain the same properties. The molded conductors of the present invention offer high withstanding power under short circuit conditions and higher insulation strength. A method of the present invention is cost comparative, since copper parts length and volume can be designed to reduce the cost and provides higher value of comparative tracking index.
[0031] 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.

[0032] 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.

CLAIMS
What is claimed is:
1) A compression mould for conductors of electrical assemblies, the mould
comprising;
a tool cavity;
a first insert placed in the tool cavity;
a pre-moulded insert coupled to the at least one insert;
a second insert placed on the pre-moulded insert ;and
a charge;
Wherein the charge is arranged on at least one of the first insert, the pre-moulded
insert and the second insert to provide compact one piece component.
2) The compression mould according to claim 1, wherein the charge is a fresh material for moulding the components.
3) The compression mould according to claim 1, wherein the pre-molded parts prevents the bridging of gap between the first insert and the second insert.
4) The compression mould according to claim 1, wherein the pre-moulded part includes a predefined geometry so as to insulate the first insert and the second insert.
5) The compression mould according to claim 1, wherein the predefined geometry provides for holding in the cavity.

6) The compression mould according to claim 1, wherein the first insert and the second insert are the conducting parts to be moulded.
7) The compression mould according to claim 1, wherein an electrical insulation is provided by at least one of a sheet moulding composite.