FORM 2
THE PATENTS ACT, 1970 (39 of 1970)
As amended 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
Device for holding the wound stator pack of an AC motor
APPLICANTS
Crompton Greaves Limited, CG House, Dr Annie Besarit Road, Worli, Mumbai - 400 030, Maharashtra, India, an Indian Company
INVENTOR
Bhujbal Eknath Ramdas, Crompton Greaves Ltd, Engineering Department, LT Motors Division (M3), A-6/2 MIDC, Ahmadnagar414 001, Maharashtra, India, Indian national
PREAMBLE TO THE DESCRIPTION
The following specification particularly describes the invention and the manner in which it is to
be performed:

FIELD OF THE INVENT/ON
This invention relates to a device for holding the wound stator pack of an AC motor.
BACKGROUND OF THE INVENTION
An AC motor comprises a cylindrical rotor concentrically rotatably mounted within a cylindrical stator in spaced apart relationship with the stator. The stator comprises a wound stator pack located concentrically within a cylindrical stator body which is usually cast iron. The wound stator pack comprises a cylindrical wound structure of stator windings with overhangs at the ends thereof Prior to assembling the wound stator pack within the stator body, lead wires of the overhang at the lead wire side of the wound stator pack are connected one by one. The leadwires are connected by supporting the wound stator pack vertically on a smooth surface, for instance, a rubber sheet spread on a table with the overhang at the non-lead wire side of the wound stator pack resting on the smooth surface. The lead wires are connected one by one by manually rotating the wound stator pack on the smooth surface. While the wound stator pack is resting on the smooth surface under its own weight and while being rotated, there are chances for the overhang at the non-lead wire side of the wound stator pack to get damaged and the rejection rates are high in spite of all the care and caution taken. As a result, there is not only wastage of materia! but also reduction in productivity. Further, a greater force and effort are required to turn the wound stator pack during connection of the lead wires as the wound stator pack is heavy and as there is increased frictional forces between the overhang and the supporting surface. This leads to operative fatigue and connection of lead wires is quite cumbersome and different to carry out.

OBJECTS OF THE INVENTION
An object of the invention is to provide a device for holding the wound stator pack of an AC motor, which device prevents damage to the overhang of the wound stator pack at the non-lead wire side thereof and wastage of material and eliminates the rejection rate of the wound stator pack and increases productivity.
Another object of the invention is to provide a device for holding the wound stator pack of an AC motor, which device reduces the force and effort required for rotating the wound stator pack during connection of the lead wires and renders connection of lead wires easy and convenient to
carry out.
DETAILED DESCRIPTION OF THE INVENTION
According to the invention there is provided a device for holding the wound stator pack of an AC motor, the device comprising a vertically disposed cylindrical member having a radius at the lower end thereof and a step internally at the upper end thereof, the inner diameter of the cylindrical member above the step corresponding to the outer diameter of the wound stator pack and the inner diameter of the cylindrical member below the step being slightly larger than the outer periphery of the overhang at the non-lead wire side of the wound stator pack and tightening means provided at the upper end of the cylindrical member for holding the wound stator pack tightly in position within the upper end of the cylindrical member against the step therein.

The following is a detailed description of the invention with reference to the accompanying drawings in which:
Fig I is a crosssectional view of the device for holding the wound stator pack of an AC motor according to an embodiment of the invention having a wound stator pack held thereon; and
Fig 2 is an exploded isometric view of the device of Fig 1 and the wound stator pack therein.
The device ! for holding the wound stator pack 2 of an AC motor (not shown) as illustrated in Figs I to 2 of the accompanying drawing comprises a vertically disposed hollow cylindrical member 3 having a radius 4 at the lower end thereof. 5 is a step formed internally at the upper end of the cylindrical member. The wound stator pack comprises a cylindrical wound structure 6 of stator windings and having an overhang 7 at the lead wire side thereof and an overhang 8 at the non lead wire side. The inner diameter of the upper end of the cylindrical member above the step corresponds to the outer diameter of the cylindrical wound stator pack. The inner diameter of the cylindrical member below the step is slightly larger than the overhang 8 at the non-lead wire side of the wound stator pack. A plurality of alien screws 9 are engaged in engaging holes provided in the upper end of the cylindrical member in radially spaced apart relationship with one another. The engaging holes have not been marked but can be clearly seen in the drawings. The heads 9a of the alien screws are disposed outside the upper end of the cylindrical member and are accessible from outside. The edges 9b of the alien screws protrude into the upper end of

the cylindrical member. The cylindrical member is, preferably made of mild steel or teflon. However, it can also be made of any other mechanically strong and durable material.
At the time of connecting the lead wires of the overhang at the lead wire side of the stator pack, the non-lead wire side of the stator pack is mounted at the upper end of the cylindrical member by locating the non-lead wire side of the wound stator pack against the inner diameter of the upper end of the cylindrical member and the step therein. The alien screws are tightened against the wound stator pack and the lead wires are connected together one by one by rotating the cylindrical member. The wound stator pack sits in the cylindrical member with the overhang at the non-lead wire side of the stator pack extending into the internal diameter of the cylindrical member below the step but without touching the internal diameter of the cylindrical member below the step as the internal diameter of the cylindrical member below the step is larger. Therefore, no damage occur to the overhang at the non-lead wire side of the stator pack during rotation of the cylindrical member for connection of the lead wires. Due to the radius, the lower end of the cylindrical member makes only a line contact with the surface on which the lower end of the cylindrical member is supported during rotation of the cylindrical member. Because of the line contact, the cylindrical member can be rotated with minimal force and effort as the frictional forces are substantially reduced.. Therefore,' rotation of the cylindrical member during connection of lead wire is easy and convenient to carry out. As a result of all this, damage to the overhang at the non-lead wire side of the stator pack and wastage of material are eliminated. Rejection rate of the stator pack is reduced and productivity is increased. Force required to rotate the cylindrical member with the stator pack is reduced. Time required for rotating the cylindrical

member with the stator pack is also reduced. Fatigue to the operator is reduced. Connection of the lead wire is rendered easy and convenient to carry out.

We claim;
1. A device for holding the wound stator pack of an AC motor, the device comprising a
vertically disposed cylindrical member having a radius at the lower end thereof and a step
internally at the upper end thereof, the inner diameter of the cylindrical member above the step
corresponding to the outer diameter of the wound stator pack and the inner diameter of the
cylindrical member below the step being slightly larger than the outer periphery of the overhang
at the non-lead wire side of the wound stator pack and tightening means provided at the upper
end of the cylindrical member for holding the wound stator pack tightly in position within the
upper end of the cylindrical member against the step therein.
2. The device as claimed in claim 1, wherein the tightening means comprises a plurality of
. alien screws engaged in engaging holes provided in the upper end of the cylindrical member in a
radially spaced apart relationship with one another with the heads of the alien screws disposed outside the cylindrical member and the edges of the alien screws projecting into the cylindrical
member.
3. The device as claimed in claim 1 or 2, wherein the cylindrical member is made of mild
steel or teflon.