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
An Improved oven for baking electrical winding
APPLICANT
Crompton Greaves Limited, CG House, Dr Annie Besant Road, Worli,
Mumbai 400 030, Maharashtra, India, an Indian Company
INVENTOR
Velingkar Vaibhav of Crompton Greaves Limited, Division, 196-198,
Kundaim IndustriaJ Estate, Kundaiam, Ponda, Goa-403115, 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 THE INVENTION:
This invention relates to the field of electronics.
Particularly, this invention relates to an improved oven for baking of electrical winding.
BACKGROUND OF THE INVENTION:
Winding in the electric motor plays an important role in the performance of the motor. It is essential for better functioning of motor to have windings properly wounded and baked in an oven. Generally the winding are placed inside the oven for one cycle of approximately 3-6 hours or more. It is required for covalent bonding of varnish. The baking temperature and time for winding is very critical and incomplete baking creates several faults such as failures of winding, bearing etc. Also, over-baking causes degradation of insulation system.
The baking process is done inside an oven having a horizontal door to be operated for opening and closing of the oven. Windings are placed inside the oven and are baked for the required baking cycle. In a microwave oven or certain similar electrical apparatus, it is desired to keep a close control over the opening and closing of an associated door since for a microwave oven, careless opening by a user of the door of the oven during the interval when its interior is supplied with microwave energy may cause hazardous results by leakage of electromagnetic radiation from the oven interior.

As a part of general practice, the windings are not treated for complete baking cycle due to which the major failure occurs. Even at the time of baking, the oven is open and closed again and again resulting in loss of proper baking. It is therefore required to device an improved oven which does not provide access to the windings before it completes a single baking cycle. Also, in case of power failures, because of temperature gradients baking cycle is not completed.
There are few prior arts which illustrate control of opening and closing of oven door.
US4166268 teaches about providing a certain degree of safety in utilizing an oven in the self-clean temperature range to insure that the door is both closed and locked before self-clean temperature ranges are achieved and also to insure that the door may not be unlocked while the oven cavity is in the self-clean temperature range and provide an improved controller switch assembly which may be utilized in both the cooking and self-clean temperature ranges. However, this patent is related to cooking activity and also does not teaches about efficient baking and loss of energy which prime objectives are of subject inventions. The patent related to cooking oven is for the purpose of safety and is only temperature dependent. There is no mention of controlled temperature and controllel time in relation to controlled temperature.
Also, US Patent US3823294 illustrates about door locking system for an electrical apparatus which is provided with a solenoid-operated contactor having contacts connected in the electrical circuit of the apparatus to which the system is applied. The energizing circuit for the solenoid of the contactor

includes at least two switching means. One of the switching means is manually operable for controlling an electromagnetic drive coil that is connected with power supply through said one switching means. This patent teaches about use of switching means (one is Manual operated) and does not mention about use of any controller. The subject invention uses a controller which works on preselected parameters (i.e. temperature as well as time) with predetermined limiting values for controlling closing and opening of doors.
None of the locking - unlocking mechanisms mentioned above provide a mechanism to ensure that a pre-determined cycle of functioning is achieved.
To overcome disadvantages associated with the prior art the proposed invention is disclosed herewith.
OBJECTS OF THE INVENTION:
An object of the invention is to provide an improved oven for baking electrical windings, wherein oven provides an efficient baking to windings in order to improve reliability of windings.
Another object of the invention is to provide an improved oven for baking electrical windings, wherein oven does not allow loss of energy due to closing and opening operations.
Yet another object of the invention is to provide a mechanism to ensure that a pre-determined cycle of functioning is achieved.

Still another object of the invention is to provide an improved oven for baking electrical windings, wherein oven does not allow the user to open the door unless one baking cycle gets over.
Another object of the invention is to compensate for the loss of temperature • gradient in case of power failure, for baking electrical windings in an oven
An additional object of the invention is to provide an improved oven for baking electrical windings, wherein oven reduces the instance of failure of winding due to lack of baking.
SUMMARY OF THE INVENTION:
According to this invention, there is provided an improved baking oven which provides a mechanism to monitor completion of pre-determined cycles of function, said oven comprises:
a. door adapted to provide entry for items to be inserted into and removed
from said oven;
b. solenoid valve adapted to control locking mechanism of said door;
c. cycle monitoring means adapted to monitor pre-determined cycles of
function of said oven; and
d. controller adapted to control operation of solenoid valve based on said
monitored cycles of function.

Typically, said oven comprises heating bank adapted to provide heat inside said oven for the purposes of baking, temperature sensor adapted to sense said temperature in said oven, blower, and discharge system.
Typically, said oven comprises power supply means adapted to power said oven.
Typically, said oven comprises timer means adapted to time cycles of function.
Typically, said oven comprises controller adapted to control the overall function of said oven, said controller being capable of controlling the power supply and opening and closing of said door with respect to predefined parameters like temperatures in the oven, time period of baking cycle, power supply conditions.
Typically, said oven comprises cycle indication means adapted to indicate status of said predefined cycle of function.
Typically, said oven comprises alarm which can sound at predefined conditions like completion of cycles of function.
BRIEF DESCRIPTION OF THE ACCOMPANYING DRAWINGS:
The invention is explained in detail with respect to accompanied figures.

Figure 1 illustrates a block diagram of oven with elements / components of the oven according to the invention; and
Figure 2 illustrates detail view of lock.
DETAILED DESCRIPTION OF THE ACCOMPANYING DRAWINGS:
For the purposes of this specification, the term, 'cycles of function' may relate to a plurality of cycles of the function of the baking oven required to achieve or complete a specific result or a task. The cycle may relate to rotation cycles, heating cycles, time cycles, temperature cycles, or any predefined oven function which is performed repetitively.
According to this invention, there is provided an improved baking oven which provides a mechanism to monitor completion of pre-determined cycles of function.
Figure 1 illustrates a block diagram of oven with elements / components of the oven according to the invention
In accordance with an embodiment of this invention, there is provided a door (6) to provide entry for items to be inserted into and removed from said oven.
In accordance with another embodiment of this invention, there is provided a solenoid valve adapted to control locking mechanism (5) of said door.

In accordance with yet another embodiment of this invention, there is provided a cycle monitoring means (12) adapted to monitor pre-determined cycles of function of said oven. Typically, the lock is so monitored that the lock is allowed to be opened only at the end of the cycle of function.
In accordance with still another embodiment of this invention, there is provided a temperature sensor adapted to sense said temperature in said oven.
In accordance with an additional embodiment of this invention, there is provided a heating bank (3) adapted to provide heat inside said oven for the purposes of baking.
In accordance with yet an additional embodiment of this invention, there is provided a blower (4).
In accordance with still an additional embodiment of this invention, there is provided a discharge system.
In accordance with another additional embodiment of this invention, there is provided a power supply means (2) adapted to power said oven.
In accordance with another additional embodiment of this invention, there is provided a timer means (8) adapted to time cycles of function.
In accordance with another additional embodiment of this invention, there is provided a controller (7) adapted to - controller means adapted to control

operation of solenoid valve based on said monitored cycles of function. The solenoid valve is adapted to unlock said door only when pre-determined number of cycles of function are completed by the oven. This number is monitored by the cycle monitoring means.
It is also adapted to control the overall function of said oven. The controller is capable of controlling the power supply and opening and closing of said door with respect to predefined parameters like temperatures in the oven, time period of baking cycle, power supply conditions, and the like. The said controller is also capable of switching the power ON or OFF.
The operation of door is directly regulated with the supply of electricity using the controller. If the power supply is on, the controller senses the signal and sends the message to release the lock of the oven. If the power supply is off, the door of the oven remains in the closed position.
In accordance with yet another additional embodiment of this invention, there is provided a cycle indication means adapted to indicate status of said predefined cycle of function.
The controller is connected with a cycle indicator which can be a timer. The cycle indicator operates only when the power supply is on and door is in closed position. In case of power failure or deliberate attempt of opening the door, the cycle indicator creates a pause by stating the actual time to which the windings were heated.

In order to bake a winding in the oven, the user has to provide power supply to the oven, after which the door of the oven can be operated. After operating the door the winding is placed inside the oven. The solenoid lock connected with the oven gets activated and locks the oven till the completion of cycle time. At the time of completion of cycle time the solenoid lock is released thereby providing access to the baked windings.
If the power supply goes off in between the cycle time the door remains lock. Even in case of deliberate attempt of opening the door, the said lock-keeps the door in close position. The cycle time can be a predetermined time, which can increase or decrease depending on the user requirement.
The proposed invention acts as the best means to save energy; at the same time providing effective baking to winding. It not only helps in saving energy but also provides a better quality output with less chances of failure.
» The controller may be optionally connected to an alarm (14) which can sound at predefined conditions like completion of baking cycle, opening of or closing of doors etc.
Preferably, the temperature at which windings are baked is about 135 deg C and the baking time is about 3 and lA hrs.
According to Figure 2, the locking means (5) comprises mounting points (9) and (10), through which the locking means is mounted on the door. The lock is manufactured by using magnet having central core winding (11) in which rod (12) is inserted. The core is connected to spring loaded latch (13). When

the power is "ON" it get magnetized and locks the door so that no one can open the door. When power is off it gets demagnetized and door is open.
Thus, with respect to input from timer means (8) and temperature sensor for the baking cycle, the controller makes Power supply ON and OFF and allows the opening of oven door in case of the power supply is OFF and vice versa. This allows the baking of electrical winding for required temperature and time without interruption and produces non defective winding.
It will be appreciated by those skilled in the art that the present invention can be embodied in other specific forms without departing from the spirit or essential characteristics thereof. The presently disclosed embodiments are therefore considered in all respects to be illustrative and not restricted. The scope of the invention is indicated by the appended claims rather than the foregoing description and all changes that come within the meaning and range and equivalence thereof are intended to be embraced therein.

We Claim,
1. An improved baking oven which provides a mechanism to monitor completion of pre-determined cycles of function, said oven comprising:
a. door adapted to provide entry for items to be inserted into and
removed from said oven;
b. solenoid valve adapted to control locking mechanism of said door;
c. cycle monitoring means adapted to monitor pre-determined cycles of
function of said oven; and
d. controller adapted to control operation of solenoid valve based on
said monitored cycles of function.
2. An oven as claimed in claim 1 wherein, said oven comprises heating bank adapted to provide heat inside said oven for the purposes of baking, temperature sensor adapted to sense said temperature in said oven, blower, and discharge system.
3. An oven as claimed in claim 1 wherein, said oven comprises power supply means adapted to power said oven.
4. An oven as claimed in claim 1 wherein, said oven comprises timer means adapted to time cycles of function.
5. An oven as claimed in claim 1 wherein, said oven comprises controller adapted to control the overall function of said oven, said controller being capable of controlling the power supply and opening

and closing of said door with respect to predefined parameters like temperatures in the oven, time period of baking cycle, power supply conditions.
6. An oven as claimed in claim 1 wherein, said oven comprises cycle indication means adapted to indicate status of said predefined cycle of function.
7. An oven as claimed in claim 1 wherein, said oven comprises alarm which can sound at predefined conditions like completion of cycles of function.