FORM 2
THE PATENTS ACT, 1970
(39 of 1970)
nded by the Patents (Amendment) Act, 2005
&
The Patents Rules, 2003
As amended by the Patents (Amendment) Rules, 2006
COMPLETE SPECIFICATION (See section 10 and rule 13)
TITLE OF THE INVENTION
A fixture for forming the wound pack overhang
APPLICANTS
Crompton Greaves Limited, CG House, Dr Annie Besant Road, Worli, Mumbai 400 030, Maharashtra, India, an Indian Company
Inventors
PINNAMARAJU.VLS.SAIBABU, Crompton Greaves Ltd, LT Motors Division, A-6/2, MIDC Industrial Area, Ahmednagar, Maharashtra-414111, India, Indian Nationals
PREAMBLE TO THE DESCRIPTION
The following specification particularly describes the nature of this invention and the manner in which it is to be performed

Field of the Invention:
This invention relates to the field of mechanical engineering.
Particularly, this invention relates to wound pack manufacturing equipment.
More particularly, this invention relates to a fixture to form the wound pack overhang during wound pack manufacturing.
Background of the Invention:
In a stator assembly, the windings may be required to be made in accordance with design parameters of size and shape. Prior art methods involved the task of hammering the overhang. This may also include the steps of pressing and compacting the windings.
In prior art, the wound pack overhang is formed manually using mallet which results into inaccurate overhang form which leads to overhang touch problems and also wound pack get damages while forming, very tidies manual operation and takes very long times.
Due to the nature of distribution of winding turns on a stator core, the prior art methods seem crude and do not warrant any finesse. After the windings have been done, due to aberrations in the prior art methods of altering the winding dimensions, there is a chance that the overhang in the stator body will result in burn-outs due to touching.
There have been a lot of rejections in wound packs during assembly due to overhang touch on other motor components. It was identified that due to lack of controlled dimensions and shape of the overhang, the overhang of the

prior art touches either end shields or rotor after assembly and consequently results into wound pack failure.
According to the prior art techniques and apparatus, there was no control over the overhang dimensions. It was purely operator skill dependent. Hence, the overhang shape formed was irregular. There was tedious manual operation involved. The cycle time for making was very high. There were more wound pack rejections due overhang touch problem.
Hence, there was a need to form the wound pack overhang shape to desired dimensions to avoid wound pack failures and obviate the above problems.
Objects of the Invention:
An object of the invention is to provide a fixture to form a wound pack overhang during wound pack manufacturing, which results into forming the over hang accurately.
Another object of the invention is to provide a fixture to form a wound pack overhang during wound pack manufacturing, which results into forming the over hang with exact pre-determined dimensions.
Another object of the invention is to provide a fixture to form a wound pack overhang during wound pack manufacturing, which eliminates over hang touch problems.

Yet another object of the invention is to provide a fixture to form a wound pack overhang during wound pack manufacturing, which reduces manual operations.
Summary of the Invention:
According to this invention, there is provided a fixture for forming wound pack overhang, said fixture comprises:
a. base plate adapted to lend base support to entire said fixture, wherein
said fixture extends in an operative vertical direction from said base
plate in a co-axial manner;
b. co-axially located bottom locator hollow ring;
c. co-axially and co-planarly located first stepped solid cylinder, having
pre-determined dimensions, with a base portion with a first diameter
and a top portion extending thereto with a second diameter, said
second diameter relatively lesser than said first diameter;
d. spacer element adapted to be co-axially placed operatively vertically
over said first stepped solid cylinder; wherein, said wound pack and
wound pack overhang are placed in a co-axial manner vertically atop
said spacer element and wherein said step in the stepped solid cylinder
is provided to receive said wound pack, the bottom locator hollow
ring, thereby, enveloping a partial bottom portion of said wound pack;
e. co-axially located top locator hollow split ring adapted to envelope
around a partial top portion of said wound pack, said split ring
including at least two arc rings joined by removable and adjustable
hinge mechanisms;
f. co-axially and co-planar located second stepped solid cylinder, having
pre-determined dimensions, with a base portion with a first diameter

and a bottom portion extending therefrom with a second diameter, said second diameter relatively lesser than said first diameter, said extending portion with said lesser diameter adapted to enter said wound pack in its final configuration to lend internal support; and g. top holder element co-axial with each of said above-mentioned elements, said top holder element adapted to hold the second stepped solid cylinder in place.
Typically, said first stepped cylinder is a bottom cone element.
Typically, said first stepped cylinder is a bottom cone element ensconced within said bottom locator hollow ring.
Typically, said spacer element is a disk.
Typically, at least one of said hinge mechanisms is an open-close hinge adapted to allow for a close fit around the wound pack in terms or adjustment.
Typically, at least one of said hinge mechanisms is fixed hinge.
Typically, said second stepped cylinder is a top cone element.
Typically, said second stepped cylinder is an inverse element as compared to
said first stepped solid cylinder.
Typically, said first stepped cylinder is a modular cylinder with varying dimensions.

Typically, said second stepped cylinder is a modular cylinder with varying dimensions.
Brief Description of the Accompanying Drawings:
The invention will now be described in relation to the accompanying drawings, in which:
Figure 1 illustrates a schematic sectional view of the fixture (100) with wound pack overhang;
Figure 2 illustrates an exploded schematic view of the fixture with wound pack overhang;
Figure 3 illustrates a schematic of a completely formed fixture with wound pack overhang;
Figure 4 illustrates a schematic of a top cone assembly of the fixture;
Figure 5 illustrates a schematic of a bottom cone assembly of the fixture; and
Figure 6 illustrates a schematic of the split ring assembly of the fixture.
Detailed Description of the Accompanying Drawings:
According to this invention, there is provided a fixture for forming wound
pack overhang.
This fixture is used for electrical winding operation in induction motor.
Figure 1 illustrates a schematic sectional view of the fixture (100) with wound pack overhang.
Figure 2 illustrates an exploded schematic view of the fixture with wound pack overhang.

Figure 3 illustrates a schematic of a completely formed fixture with wound pack overhang.
Figure 4 illustrates a schematic of a top cone assembly of the fixture.
Figure 5 illustrates a schematic of a bottom cone assembly of the fixture.
Figure 6 illustrates a schematic of the split ring assembly of the fixture.
In accordance with an embodiment of this invention, there is provided a base plate (12) which lends base support to the entire fixture. The fixture (100) extends in an operative vertical direction from said base plate in a co-axial manner.
In accordance with another embodiment of this invention, there is provided a co-axially located bottom locator hollow ring (14).
In accordance with yet another embodiment of this invention, there is provided a co-axially and co-planar located first stepped solid cylinder (16) with a base portion with a first diameter and a top portion extending thereto with a second diameter, said second diameter relatively lesser than said first diameter. This is also known as the bottom cone element. It is ensconced within the bottom locator hollow ring (14).
In accordance with still another embodiment of this invention, there is provided a spacer element (18) adapted to be co-axially placed operatively vertically over said first stepped solid cylinder (16). Typically, the spacer element (18) is a disk.

The wound pack (200) and wound pack overhang (250) is placed in a coaxial manner vertically atop said spacer element. The step in the stepped solid cylinder is provided to receive the wound pack (200). Thus, the bottom locator hollow ring (14) envelopes a partial bottom portion of the wound pack (200).
In accordance with an additional embodiment of this invention, there is provided a top locator hollow split ring (22) adapted to envelope around a partial top portion of the wound pack (200). The split ring (22) includes at least two arc rings which are joined by removable and adjustable hinge mechanisms (24, 26). One may be an open-close hinge (24) and another may be a diametrically oppositely located fixed hinge (26). The open-close hinge (24) allows for a close fit around the wound pack in terms or adjustment.
In accordance with yet an additional embodiment of this invention, there is provided a co-axially and co-planar located second stepped solid cylinder (28) with a base portion with a first diameter and a bottom portion extending therefrom with a second diameter, said second diameter relatively lesser than said first diameter. This is also known as the top cone element. This is an inverse element as compared to the first stepped solid cylinder (16). The extending portion with the lesser diameter is adapted to enter the wound pack (200) in its final configuration to lend internal support to the overhang (200).
In accordance with still an additional embodiment of this invention, there is provided a top holder element (32) co-axial with each of said above-

mentioned elements. The top holder element (32) is adapted to hold the top cone element in place (28).
The top and bottom cones are the forming tools which may be selected according to the dimensions of the wound pack overhang. So also, the bottom locator element may be selected according to the dimensions of the wound pack overhang. The top split ring may be adjusted to fit the overhang.
The invention uses simple top and bottom forming tooling as per final over hang requirement. Top tooling has split type external ring and solid internal tooling combination of both the tooling creates a cavity to form the desired overhang shape and dimensions. This fixture is capable to form external, internal and length to required dimensions very easily. The fixture is made by metal or polymer material for to avoid copper damages.
This fixture facilitates to form the wound pack overhang in three dimensions i.e. its external diameter, its internal diameter, and its height. This fixture can be mounted in Pneumatic, Hydraulic and mechanical press.
While this detailed description has disclosed certain specific embodiments of the present invention for illustrative purposes, various modifications will be apparent to those skilled in the art which do not constitute departures from the spirit and scope of the invention as defined in the following claims, and it is to be distinctly understood that the foregoing descriptive matter is to be interpreted merely as illustrative of the invention and not as a limitation.

We claim,
1. A fixture for forming wound pack overhang, said fixture comprising:
a. base plate adapted to lend base support to entire said fixture, wherein
said fixture extends in an operative vertical direction from said base
plate in a co-axial manner;
b. co-axially located bottom locator hollow ring;
c. co-axially and co-planarly located first stepped solid cylinder, having
pre-determined dimensions, with a base portion with a first diameter
and a top portion extending thereto with a second diameter, said
second diameter relatively lesser than said first diameter;
d. spacer element adapted to be co-axially placed operatively vertically
over said first stepped solid cylinder; wherein, said wound pack and
wound pack overhang are placed in a co-axial manner vertically atop
said spacer element and wherein said step in the stepped solid cylinder
is provided to receive said wound pack, the bottom locator hollow
ring, thereby, enveloping a partial bottom portion of said wound pack;
e. co-axially located top locator hollow split ring adapted to envelope
around a partial top portion of said wound pack, said split ring
including at least two arc rings joined by removable and adjustable
hinge mechanisms;
f. co-axially and co-planar located second stepped solid cylinder, having
pre-determined dimensions, with a base portion with a first diameter
and a bottom portion extending therefrom with a second diameter,
said second diameter relatively lesser than said first diameter, said
extending portion with said lesser diameter adapted to enter said
wound pack in its final configuration to lend internal support; and

g. top holder element co-axial with each of said above-mentioned elements, said top holder element adapted to hold the second stepped solid cylinder in place.
2. A fixture as claimed in claim 1 wherein, said first stepped cylinder is a bottom cone element.
3. A fixture as claimed in claim 1 wherein, said first stepped cylinder is a bottom cone element ensconced within said bottom locator hollow ring.
4. A fixture as claimed in claim 1 wherein, said spacer element is a disk.
5. A fixture as claimed in claim 1 wherein, at least one of said hinge mechanisms is an open-close hinge adapted to allow for a close fit around the wound pack in terms or adjustment.
6. A fixture as claimed in claim 1 wherein, at least one of said hinge mechanisms is fixed hinge.
7. A fixture as claimed in claim 1 wherein, said second stepped cylinder is a top cone element.
8. A fixture as claimed in claim 1 wherein, said second stepped cylinder is an inverse element as compared to said first stepped solid cylinder.

9. A fixture as claimed in claim 1 wherein, said first stepped cylinder is a modular cylinder with varying dimensions.
10. A fixture as claimed in claim 1 wherein, said second stepped cylinder is a modular cylinder with varying dimensions.