FORM 2
THE PATENT ACT 1970
&
The Patents Rules, 2003
COMPLETE SPECIFICATION (See section 10 and rule 13)
1. TITLE OF THE INVENTION:
"Temperature Monitoring and Recording with Automatic Locking Mechanism for Baking Oven"
2. APPLICANT:
(a) NAME: Larsen & Toubro Limited
(b) NATIONALITY: Indian Company registered under the
provisions of the Companies Act-1956.
(c) ADDRESS: Larsen & Toubro Limited
L&T House, Ballard Estate, MUMBAI-400001, Maharashtra State, INDIA
3. PREAMBLE TO THE DESCRIPTION:
COMPLETE
The following specification particularly describes the invention and the manner in which it is to be
performed.

Temperature Monitoring and Recording with Automatic Locking Mechanism
for Baking Oven
Field of the invention
The present invention relates to a locking mechanism for a baking oven, more particularly, it relates to an automatic locking mechanism with temperature monitoring and recording for an industrial baking oven to ensure a complete baking cycle.
Background of the invention
Conventionally, oven doors are retained by a latch mechanism which may be used to lock the doors of the oven to prevent accidental or inadvertent opening of an oven doors. However, such latch mechanism allows the manual intervention during the baking cycle of the oven, which may lead to incomplete baking of the material inside the oven. An incomplete baking cycle may result in moisture content in material to be baked. This can lead to major defects in further processes where it is used. To overcome this, an interlocking of the oven may be provided using the magnetic locks. However, such magnetic locks may unlock the oven door in case of power failure during the baking cycle leading to incomplete baking cycle. Accordingly, there is a need for the interlocking facility for the oven which prevents any manual intervention in opening the oven door before the baking cycle is complete.
Object of the present invention
An object of the present invention is to provide a temperature monitoring and recording with automatic locking mechanism for baking oven, which is capable of avoiding manual intervention.

Another object of the present invention is to provide an automatic locking mechanism for baking oven with temperature monitoring and recording, which ensures completion of a baking cycle of the oven before unlocking.
Another object of the present invention is to provide an automatic locking mechanism for baking oven with temperature monitoring and recording having an online display of temperature in digital/ graphical format and transferring of records to Office PC via Wifi/LAN/CF card.
Statement of the invention
According to the present invention, there is provided an automatic locking mechanism for baking oven comprising:
a first bracket juxtaposed to a door of the oven;
a rack housed in a rack holder for locking and unlocking the door of the oven, wherein the rack holder is secured to the first bracket;
a pinion secured on the rack holder to mesh the rack, the pinion upon rotation capable of moving the rack in vertical direction;
a driving means coupled with the pinion for rotating the pinion;
a second bracket mounted on the first bracket, the second bracket aligned with the rack, the second bracket having a first limit switch and a second limit switch configured thereon at a predefined distance;
a plate secured to the rack for operating the first limit switch and second limit switch; and
a control panel having temperature recorder for monitoring and recording temperature thereof, the control panel capable of monitoring temperature of the oven and provide signals for operating the driving means for locking and unlocking the door of the oven;

wherein upon receiving the signal from the control panel, the driving means rotates the pinion thereby moving the rack along with the plate to a downward direction and the plate activates the first limit switch thereby cutting the signal to the driving means for locking the door of the oven, and thereafter when the baking cycle of the oven is complete, the control panel provides signal to the driving means for rotating the pinion thereby moving the rack along with plate to an upward direction and the plate activates the second limit switch thereby cutting the signal to the driving means for rotating the pinion for unlocking the door of the oven.
Typically, wherein the driving means is at least one selected from group consisting of DC motor, stepper motor, plural phase AC induction motor, a hydraulic motor and a pneumatic motor.
Typically, wherein the temperature recorder having display means for displaying the temperature.
Brief description of the drawings
Figures 1 shows a perspective view of an automatic locking mechanism and temperature monitoring means for a baking oven in according to the present invention; and
Figure 2 shows a perspective view of a baking oven in a locked position by the locking mechanism.

Detail description of the invention
The foregoing objects of the invention are accomplished and the problems and shortcomings associated with the prior art techniques and approaches are overcome by the present invention as described below in the preferred embodiment.
The present invention provides a temperature monitoring and recording with automatic locking mechanism for baking oven. Specifically, the automatic locking mechanism for the baking oven is capable of avoiding manual intervention in the baking oven during baking cycle, and additionally provides means for motoring temperature and recording thereof. Further, the locking mechanism for a baking oven ensures completion of a baking cycle of the oven before unlocking doors of the baking oven.
The present invention is illustrated with reference to the accompanying drawings, throughout which reference numbers indicate corresponding parts in the various figures. These reference numbers are shown in bracket in the following description.
Referring now to figure 1 and 2, there is provided an automatic locking mechanism for a baking oven. More specifically, the figure 1 and 2 shows the baking oven (200) having the locking mechanism (100). The locking mechanism (100) includes a first bracket (10), a rack holder (20), a rack (30), a pinion (40), a driving means (50), a second bracket (60), a plate (70) and a control panel (80).
The first bracket (10) is juxtaposed to the doors of the baking oven (200). Specifically, the first bracket (10) is secured to an upper portion of a front surface (120) close to the doors of the baking oven (200). The first bracket (10) may be secured to the upper portion of the front surface (120) of the baking oven (200) by nuts and bolts. However, it may be evident to those skilled in the art to use any other

mechanism, such as welding for securing the first bracket (10) to the baking oven (200). The first bracket (10) is a base for supporting the rack holder (20).
The rack holder (20) includes a rack (30) housed therein. The rack holder (20) allows vertical movement of the rack (30) therewithin so as to hold the doors of the baking oven (200) in locked position when the rack (30) moves in downward direction and clear the door to open it in unlocked position when the rack (30) moves in upward direction. The rack (30) is sufficiently long to maintain locking and unlocking of the doors by the vertical movement thereof. The rack holder (20) may be secured to the first bracket (10) by means of nuts and bolts. However, it may be evident to those skilled in the art to use any other mechanism to secure the rack holder (20) to the first bracket (10). The rack (30) meshes the pinion (40).
Specifically, the pinion (40) is secured on the rack holder (20) from one side. The pinion meshes the rack (30) thereby moving the rack (30) vertically through the rack holder (20) when the pinion (40) is rotated by a driving means (50). The driving means (50) is at least one selected from group consisting of DC motor, stepper motor, plural phase AC induction motor, a hydraulically controlled device and a pneumatically Controlled device. Specifically, the driving means (50) is a DC motor. More specifically, the pinion's shaft (not shown) is coupled with a DC motor through a printed circuit board inside the control panel (80). The driving means (50) rotates the pinion (40) which in turn moves the rack (30) vertically within the rack holder (20).
The second bracket (60) is mounted on the first bracket (10) by suitable means such as nuts and bolts. Specifically, the second bracket is (60) aligned with the rack (30). More specifically, the second bracket is (60) aligned with a side of the rack (30). The second bracket (60) includes a first limit switch (62) and a second limit switch (64) configured thereon at a predefined distance. Specifically, the first limit switch (62) in

mounted on the second bracket (60) at a lower portion thereof and the second limit switch (64) in mounted on the second bracket (60) at an upper portion thereof. The plate (70) is secured to the rack (30) for operating the first limit switch (62) and the second limit switch (64). More specifically, the plate (70) is L- shaped plate secured to the side of the rack (30) such that the projection of the plate (70) touches the first limit switch (62) and the second limit switch (64) to activate them when the rack (30) reciprocated vertically by the pinion (40). The pinion (40) is rotated by the driving means (50) upon receiving signals from the control panel (80).
The control panel (80) includes a temperature recorder (90) which is capable of monitoring and recording the temperature of the baking oven (200). Further, the control panel (80) provides signals to the driving means (50) for rotating the pinion (40) based upon the temperature of the baking oven (200).
The recorder placed inside the control panel (80) is programmed so as to give output signal firstly when baking cycle starts. The driving means (50) upon receiving such signal from the control panel (80) rotates the pinion (40) thereby moving the rack (30) along with the plate (70) to a downward direction until the projection of the plate (70) touches the first limit switch (62). At the same time the first limit switch (62) gets activated and cuts the signal to the driving means (50) for rotating the pinion (40) thus resting the rack (30) over the doors of the baking oven (200) thereby locking the baking oven (200).
Further, the control panel (80) along with temperature recorder (90) continuously monitors a rise in temperature and provides continuous signals until preset temperature is reached. The temperature recorder (90) includes a display means for displaying the temperature. Then material to be baked is held at that temperature for specified soaking period and after that rate of cooling is adjusted by control panel to reach at lower temperature, this marks the end of baking cycle. This baking cycle is

programmable in the temperature recorder and operation of lock can be directed accordingly. The driving means (50) upon receiving the signal from the control panel (80) rotates the pinion (40) thereby moving the rack (30) along with the plate (70) to an upward direction until the projection of the plate (70) touches the second limit switch (64). Thus, the second limit switch (64) gets.activated and cuts the signal to the driving means (50) for rotating the pinion (40) thereby resting the rack (30) above the doors of the baking oven (200) for unlocking the baking oven (200).
According to the present invention, the locking mechanism (100) is used on a double door baking oven. However, it may be evident to those skilled in the art to use the locking mechanism (100) on a single door baking oven.
Advantages of the invention
The automatic locking mechanism for a baking oven of the present invention has various advantages. The locking mechanism for a baking oven avoids manual intervention during a baking cycle. Further, the locking mechanism for a baking oven ensures completion of a baking cycle of the oven before unlocking.
It is to be understood that the present invention is not limited in its application to the details of the construction and to the arrangement of the components as mentioned in the above description or illustrated in the drawings. However, it is to be taken as the preferred example of the invention and that various changes in the shape, size and arrangement of parts considering the space constraint way be resorted to without departing from the spirit of the invention. The invention is capable of other embodiments and of being practiced and carried out in various ways. Also, the terminologies used herein are for the purpose of description and should not be regarded as limiting.

We claim
1. An automatic locking mechanism for an oven comprising:
a first bracket juxtaposed to a door of the oven;
a rack housed in a rack holder for locking and unlocking the door of the oven, wherein the rack holder is secured to the first bracket;
a pinion secured on the rack holder to mesh the rack, the pinion upon rotation capable of moving the rack in vertical direction;
a driving means coupled with the pinion for rotating the pinion;
a second bracket mounted on the first bracket, the second bracket aligned with the rack, the second bracket having a first limit switch and a second limit switch configured thereon at a predefined distance;
a plate secured to the rack for operating the first limit switch and second limit switch; and
a control panel having temperature recorder for monitoring and recording temperature thereof, the control panel capable of monitoring temperature of the oven and provide signals for operating the driving means for locking and unlocking the door of the oven;
wherein upon receiving the signal from the control panel, the driving means rotates the pinion thereby moving the rack along with the plate to a downward direction and the plate activates the first limit switch thereby cutting the signal to the driving means for locking the door of the oven, and thereafter when the baking cycle of the oven is complete, the control panel provides signal to the driving means for rotating the pinion thereby moving the rack along with plate to an upward direction and the plate activates the second limit switch thereby cutting the signal to the driving means for rotating the pinion for unlocking the door of the oven.

2. The automatic locking mechanism as claimed in claim 1, wherein the driving means is at least one selected from group consisting of DC motor, stepper motor, plural phase AC induction motor, a hydraulic motor or a pneumatic motor.
3. The automatic locking mechanism as claimed in claim 1, wherein the temperature recorder having display means for displaying the temperature.
4. The automatic locking mechanism substantially shown and described in the specification with accompanying drawings.