FORM 2
THE PATENTS ACT, 1970
(39 of 1970)
As amended by the Patents (Amendment) Act, 2005
AND
The Patents Rules, 2003
As amended by the Patents (Amendment) Rules, 2005
COMPLETE SPECIFICATION
(See section 10 and rule 13)
TITLE OF THE INVENTION A novel air guide for motors.
APPLICANTS
Crompton Greaves Limited, CG House, Dr Annie Besant Road, Worli, Mumbai 400 030, Maharashtra, India, an Indian Company
INVENTOR
Das Mukul of Crompton Greaves Ltd, machine (M7) Division, D-5 Industrial Area, MPAKVN, Mandideep-462046, Madhya Pradesh, India, an Indian National
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 INVENTION:
This invention relates to the field of motors and particularly to closed air circuit air cooled motors.
Still particularly, this invention relates to an air guide for motor.
Particularly, this invention envisages a novel air guide for motors in order to maintain the air flow circuit as per requirements without changing the position of internal fan.
BACKGROUND OF INVENTION:
Motors are susceptible to generate heat during its operative configuration. It is important that this generated heat i.e. hot air is guided appropriately away from the motor, typically towards a heat exchanger for efficient use of said motor, and said heat exchanger.
Conventionally, HT induction motors are provided with the air guides which are used to guide the internal air from motor to the heat exchanger. Presently, the air guide is designed in such a way that there is a need to change the internal fan position to appropriately channel the air flow circuit.
There is, hence, a need to overcome this limitation and provide the flexibility to maintain air flow circuit as per user requirements without changing the position of the internal fan.

OBJECTS OF INVENTION:
An object of the invention is to provide an air guide for motor which provides the flexibility to maintain the air flow circuit as per user's requirements without changing in the axial position of the internal fan.
Another object of the invention is to provide an air guide for motor which saves time and manpower cost by eliminating the step of changing of position of internal fan.
Yet another object of the invention is to provide an air guide for motor wherein upper racks of a stator frame need not to be changed everytime.
Still another object of the invention is to provide an air guide for motor wherein said air guide includes proper width and maintains the opening as required.
SUMMARY OF THE INVENTION:
According to this invention, there is provided an air guide for motors for guiding air from a motor and stator to a heat exchanger, said air guide comprises:
a. an inner middle ring in communication with an overhang of said
stator for cooling said stator; and
b. a top ring jacketed over said inner middle ring, said top ring
extending out of said inner middle ring from one of its lateral sides.
Typically, said top ring is cylindrical.

Typically, said inner middle ring is cylindrical.
Typically, said outer ring is mounted on stator ribs.
Typically, said inner ring is mounted on said outer ring of air guide.
Typically said motors are closed air circuit air cooled motor, closed air circuit water cooled motor and totally enclosed tube ventilation motor.
BRIEF DESCRIPTION OF THE ACCOMPANYING DRAWINGS:
Figure 1 illustrates a schematic view of the air guide of the prior art mounted with respect to motor, stator, heat exchanger, internal fan and overhang;
Figure 2 illustrates a schematic isometric view of the air guide in accordance with the prior art;
Figure 3a illustrates a schematic front view of the air guide in accordance with the prior art; and
Figure 3b illustrates a schematic side view of the air guide in accordance with the prior art.
The invention will now be described in relation to the accompanying drawings, in which:
Figure 4 illustrates a schematic view of the air guide of the mounted with respect to motor, stator, heat exchanger, internal fan and overhang;

Figure 5 illustrates a schematic isometric view of the novel air guide;
Figure 6a illustrates a schematic side view of the novel air guide; and Figure 6b illustrates a schematic side view of the novel air guide.
DETAILED DESCRIPTION OF THE INVENTION:
Figure 1 illustrates a schematic view of the air guide of the prior art mounted with respect to motor, stator, heat exchanger, internal fan and overhang.
Figure 2 illustrates a schematic isometric view of the air guide (100) in accordance with the prior art.
Figure 3 a illustrates a schematic front view of the air guide (100) in accordance with the prior art, and
Figure 3b illustrates a schematic side view of the air guide (100) in accordance with the prior art.
The air guide of the prior art comprises a top wrap (110) i.e. an outer (top) ring and a middle wrap (120) i.e. an inner (middle) ring. Said inner ring is ensconced within said outer ring, each of said rings being a cylinder with equal heights.

As seen in Figure 1, a stator (130) is fitted between a motor (140) and heat exchanger (150). Through one of the lateral sides of the stator, an overhang (160) is provided such that it receives with said air guide (100). The outer ring (110) and inner ring (120) are shown. The air through the air guide flows through the opening (170) to the heat exchanger. An internal fan (190) guides the movement of the air.
Figure 4 illustrates a schematic view of the novel air guide of the invention wherein the air guide (200) is mounted with respect to motor (140), stator (130), heat exchanger (150), internal fan (190) and overhang (160).
Figure 5 illustrates a schematic isometric view of the novel air guide.
Figure 6a illustrates a schematic side view of the novel air guide; and
Figure 6b illustrates a schematic side view of the novel air guide.
According to the invention there is provided a novel air guide for motors, typically for closed air circuit air cooled motors, said air guide comprising a top ring (210) and an inner middle ring (220), wherein, said top ring has been extended till the position required for maintaining the opening in the stator frame to pass the internal air from stator frame to heat exchanger. Here, the middle ring is located so as to cool the overhang portion of stator coil. In the new design there is no limitation of keeping the middle baffle at the end point of top baffle. Hence, there is no need to change the position of internal fan to maintain the air flow circuit.

Typically, said novel air guide for motor is provided near the overhang portion stator in motor.
In accordance with an embodiment of this invention, said air guide comprises two rings (top outer ring and middle inner ring). Typically, said rings are cylindrical in shape and adapted to be mounted on motor stator frame ribs.
In accordance with another embodiment of this invention, said top ring is mounted on stator ribs and said inner ring is mounted on outer ring of air guide.
Typically said motors are closed air circuit air cooled motor, closed air circuit water cooled motor and totally enclosed tube ventilation motor.
Although this invention is explained with relation to air guides for closed air circuit air cooled motors, it is understood that it is also applicable to closed air circuit water cooled motor, totally enclosed tube ventilation motors, and the like.

We claim:
1. A novel air guide for motors for guiding air from a motor and stator to
a heat exchanger, said air guide comprising:
a. an inner middle ring in communication with an overhang of said
stator for cooling said stator; and
b. a top ring jacketed over said inner middle ring, said top ring
extending out of said inner middle ring from one of its lateral sides.
2. The air guide as claimed in claim 1 wherein, said top ring is cylindrical.
3. The air guide as claimed in claim 1 wherein, said inner middle ring is cylindrical.
4. The air guide as claimed in claim 1 wherein, said outer ring is mounted on stator ribs.
5. The air guide as claimed in claim 1 wherein, said inner ring is mounted on said outer ring of air guide.