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
A steam based cooking system
APPLICANT
Flareum Technologies Private Limited, an Indian company having address as 701, AC Market,
Tardeo road, Mumbai-400 034, Maharashtra, India, an Indian company
PREAMBLE TO THE DESCRIPTION
The following specification particularly describes the invention and the manner in which it is to
be performed:

FIELD OF THE INVENTION
[0001] The present invention relates generally to cooking systems for cooking food
items and more particularly, to steam based cooking systems.
DESCRIPTION OF THE BACKGROUND ART
[0002] Cooking apparatuses such as cookers, ovens or the like utilizing electricity or
cooking gas as a medium to cook food items have been used in households for many years now. These cooking apparatuses especially cookers are scalable to larger sizes to prepare large quantities of food quickly and conveniently at places like hospitals, restaurants, religious places, food caterers, government organizations, schools, etc. Considering the large quantities of food prepared and served in the form of meals at these places, the primary emphasis is given to the capacity of cooking apparatuses while installing such cooking apparatuses at a given place. Efficiency of cooking apparatuses in terms of their energy saving capabilities generally comes secondary, and in some cases ignored. Such criteria has traditionally led to undue consumption (or in other terms wastage) of electricity and cooking gas during large scale food preparation.
[0003] Nowadays, in the Clean/Green technology era, there is immense focus and
attention on preserving conventional energy, and keeping this in view several governments across the world have announced incentives to manufacturers and suppliers who are in the cleantech business. Encouraged by this drive some manufacturers who make large scale cooking apparatuses and systems have started to make 'steam' based cooking systems that use steam generated from solar energy to cook food items. Such steam based cooking systems that have capacity to prepare large quantities of food have been successfully installed at the above referred places.
[0004] Though such steam based cooking systems are successfully preparing large
quantities of food items, manufacturers however do not seem to have given due consideration to their energy savings capabilities when the steam based cooking systems are operating. As a result, most of the steam based cooking systems operate under reduced efficiency levels.

There could be possible reasons attributed to the steam based cooking systems working under decreases efficiency levels.
[0005] First, most of these cooking systems are operated manually in which steam is
continuously fed within a cooking vessel irrespective of the build up temperature within the cooki ng vessel. Based on his experience and visual identification, the operator determines the state of the cooked food, removes the cooked food, and prepares for further cooking of the same food item or other food items. Generally, the cooking process is progressively carried on for a specific period of time with the cooking vessel continuously receiving the supply of steam. Once all the food items are cooked the operator turns off the cooking systems thereby stopping the supply of steam received within the cooking vessel. Practically, occasions would be rare when the operator would take due care of stopping the supply of steam whenever the food item is cooked. Second, most of the steam based cooking systems do not have mechanisms to optimize consumption of steam required during cooking of food items. As a result of these drawbacks, there is a significant amount of steam unnecessarily consumed or wasted in such cooking systems thereby reducing their efficiency levels.
[0006] Thus, there is a need to develop an automatic and efficient steam based cooking
systems that overcomes at least some of the abovementioned drawbacks.
SUMMARY OF THE INVENTION
[0007] Accordingly disclosed herein is a steam based cooking system including a cooking
vessel including an inlet tube, an outlet tube, and a temperature sensing device partially insertable within the cooking vessel for measuring internal cooking temperature when the food items are cooked and generating electrical signals responsive to the measured cooking temperature, an inlet solenoid valve connected to the inlet tube, the inlet solenoid valve when operable in an open position allowing steam receivable from a steam generating source to enter the cooking vessel and when operable in a closed position preventing the steam from entering the cooking vessel, an outlet solenoid valve connected to the outlet tube, the outlet solenoid valve when operable in an open position allowing drainage of a condensate from the cooking vessel and when operable in a closed position preventing drainage of the condensate,

and a controller communicatively coupled to the inlet and outlet solenoid valves for controlling their opening and closing, the controller communicatively coupled to the temperature sensing device for receiving the electrical signals and determining an actual cooking temperature corresponding to each of the electrical signal, the controller configured to, compare each of the determined actual cooking temperature with a pre-stored maximum temperature of the food item, and disposes the inlet solenoid valve from the open position to the closed position if the actual cooking temperature exceeds the pre-stored maximum cooking temperature, and periodically dispose the outlet solenoid valve from the closed position to the open position based on a pre-stored drainage time interval.
[0008] In some embodiments, the controller is configured with a program that has pre-
stored maximum and minimum temperature of food items that are to be cooked within the cooking vessel, and wherein the program has a pre-stored cyclic drainage time interval for periodically draining the condensate.
[0009] In some embodiments, the controller is configured to dispose the inlet solenoid
valve from the open position to the closed position to prevent inflow of the steam within the cooking vessel when the outlet solenoid valve is disposed in the open position.
[0010] In some embodiments, the steam based cooking system further includes a
control panel, the control panel comprising a food selector switch for selecting food items for cooking, an ON/OFF switch for starting and stopping the cooking operation, and a MODE knob for carrying out operations in auto and manual modes, the controller is positioned inside the control panel.
[0011] In some embodiments, the cooking vessel further includes an elongated jacket
formed around an inner surface of the cooking vessel in spaced apart relationship and having a sealed top end, and wherein an end of the inlet tube is insertable within the jacket through a first opening formed on an outer surface of the cooking vessel for allowing steam to be dispensed within the jacket.
[0012] In some embodiments, the outer surface of the cooking vessel and the jacket are
formed to have a first concentric opening and the temperature sensing device is partially

insertable inside the cooking vessel through the first concentric opening, and wherein portion of the temperature sensing device exposed within the jacket is covered with an insulating material securely disposed within the jacket.
[0013] In some embodiments, the temperature sensing device includes a Resistance
Temperature Detector (RTD) having a temperature sensing end, the RTD securely disposed within a thermowell in a manner that the temperature sensing end is exposed therefrom, and wherein the temperature sensing end is exposed to the interior of the cooking vessel when the thermowell is partially insertable within the cooking vessel for measuring cooking temperature of the food items.
[0014] In some embodiments, wherein the outer surface of the cooking vessel and the
jacket are formed to have a second concentric opening, a temperature gauge having a temperature sensing end is partially insertable inside the cooking vessel from outside through the second concentric opening in a manner that the temperature sensing end is exposed to the interior of the cooking vessel for measuring cooking temperature of the food items , and wherein portion of the temperature gauge exposed within the jacket is covered with an insulating material securely disposed within the jacket.
[0015] It is to be understood that both the foregoing general description and the
following detailed description of the present embodiments of the invention are intended to provide an overview or framework for understanding the nature and character of the invention as it is claimed. The accompanying drawings are included to provide a further understanding of the invention and are incorporated into and constitute a part of this specification. The drawings illustrate various embodiments of the invention and together with the description serve to explain the principles and operation of the invention.
A BRIEF DESCRIPTION OF THE DRAWINGS
[0016] The above-mentioned and other features and advantages of the various
embodiments of the invention, and the manner of attaining them, will become more apparent and will be better understood by reference to the accompanying drawings, wherein:

[0017] FIG. 1 is a sectional view of an embodiment of a cooking system electrically
connected to a control panel when seen from front according to the present invention; and
[0018] FIG. 2 is a sectional view of the cooking system of FIG. 1 when seen from its side.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0019] FIG. 1 shows an embodiment of a cooking system 100 capable of working in
automatic and manual modes according to the present invention. The cooking system 100 includes a cooking vessel 102 supported over a support structure 104 in a manner shown in FIG. 1. Preferably, the cooking vessel 102 is formed from a longitudinal cylindrical body 106 extending between an open end 108, a torispherical bottom end 110 and an elongated jacket 112 disposed inside the cylindrical body 106. The elongated jacket 112 is arranged around an inner surface 114 of the cooking vessel 102 in spaced apart relationship. Preferably, the elongated jacket 112 is cylindrical in shape and has a top end 116 arranged concentric to the open end 108 of the cylindrical body 106. An open space between the top end 116 of the jacket 112 and the open end 108 of the cooking vessel 102 is sealed by using an appropriate sealing material 118, or by any other means. Food items 120 such as rice, dal, vegetables, etc. along with water are placed inside the cooking vessel 102 through the open end 108, which may be covered by a lid 122 suitably fabricated to provide a tight fitting to the open end 108 of the cylindrical body 106 of the cooking vessel 102.
[0020] The cylindrical shapes of the cooking vessel 102 and the elongated jacket 112
should not be construed to be limiting to the overall scope of the present invention as according to several other embodiments, the cooking vessel 102 and the elongated jacket 112 may also have various other complimentary and non-complimentary shapes. In some other embodiments of the cooking vessel 102 according to the present invention, the elongated jacket 112 may be formed as an internal part of the cooking vessel 102 during fabrication of the cooking vessel 102. Furthermore, in several other embodiments of the cooking vessel 102, the cooking vessel 102 may not have a lid 122 for covering the open end 108 thereof. A skilled person in the art would understand that all these alternative embodiments should be construed to be within the scope of the present invention.

[0021] As seen in FIG. 1, the cooking vessel 102 includes an inlet tube 124 and an outlet
tube 126 operably connected to the cooking vessel 102. The inlet tube 124 extends between a steam receiving end 128 and a steam dispensing end 130. The steam receiving end 128 is connected to a steam generating source (not shown) for receiving steam therefrom via a solar header (not shown) connected to the steam generating source. Preferably, the steam generating source is an assembly of parabolic solar collectors and receiver used for generating steam. Preferably, the steam dispensing end 130 of the inlet tube 124 is inserted within the jacket 112 through a first opening 132 formed on an outer surface 134 of the cooking vessel 102. The steam dispensing end 130 dispenses steam within the jacket 112 for cooking food items 120 inside the cooking vessel 102. Heat energy of the dispensed steam is used to heat food items 120 present within the cooking vessel 102 for cooking purpose. In various other embodiments of the steam generating source according to the present invention, other steam generating mechanisms may also be used and operably connected to the steam receiving end 128 of the inlet tube 124.
[0022] As seen in FIG. 2, the outlet tube 126 extends between a condensate receiving
end 136 and a condensate dispensing end 138. The condensate receiving end 136 is connected to the torispherical bottom end 110 of the cooking vessel 102 through a second opening 140 formed therein. The outlet tube 126 periodically drains the condensate accumulated inside the jacket 112 of the cooking vessel 102 through the condensate dispensing end 138 of the outlet tube 126 (See FIG. 2).
[0023] An inlet solenoid valve 142, an inlet tube manual valve (V,) and a pressure
regulating valve 144 are disposed in series with each other and operably connected to the inlet tube 124 in a manner shown in FIG. 1. The pressure regulating valve 144 includes a first pressure gauge and a second pressure gauge (not shown) installed at an inlet and an outlet of the pressure regulating valve 144. Preferably, the inlet tube 124 also includes a by-pass passage (BPt) extending between the manual valve (V|) and the inlet solenoid valve 142 and rejoining the inlet tube 124 at a distance prior to the steam dispensing end 130. The by-pass passage (BPt) also has a manual valve (VBPI) operably connected thereto. As seen from FIG. 2, the outlet tube 126 of the cooking vessel 102 includes an outlet solenoid valve 145 and an

outlet tube manual valve (Vo) disposed in series with each other and operably connected to the outlet tube 126. Preferably, the outlet tube 126 also includes a by-pass passage (BP0) extending between the manual valve (V0) and the outlet solenoid valve 145 and rejoining the outlet tube 126 at a distance prior to the condensate dispensing end 138 of the outlet tube 126. The bypass passage (BPO) also has a manual valve (V6PO) operably connected thereto.
[0024] As seen from FIGS. 1 and 2, both the inlet solenoid valve 142 and the outlet
solenoid valve 145 are electrically connected to a controller 146 positioned inside a control panel 148. Both the inlet and outlet solenoid valves 142, 145 are operable in two positions- an open position and a closed position- and their opening and closing operations is controlled by the controller 146. Preferably, the inlet and outlet solenoid valves 142,145 that are used in the cooking system 100 are induction type solenoid valves however other types of solenoid valves could also be used as an alternative to the induction type solenoid valve and considered to be within the scope of the present invention.
[0025] The cooking system 100, as noted earlier, could be operated in two modes-
automatic mode and manual mode. Regardless of the two cooking modes, the steam received from the steam generating source passes through the pressure regulating valve 144 pre-set to allow the steam having a constant pressure of 3 kg/cm2 to flow downstream to the inlet tube 124. The inlet tube manual valve (V|), which is a one-way valve, is disposed adjacent to the second pressure gauge of the pressure regulating valve 144 is always disposed in its open position to allow the constant pressure steam to pass further downstream of the inlet tube 124. Further, regardless of the two cooking modes, the by-pass manual valve (VBPI) is always disposed in its closed position by an operator so that the constant pressure steam is allowed to take the normal passage having the inlet solenoid valve 142. However, in case the inlet solenoid valve 142 malfunctions and the constant pressure steam is required to be dispensed within the jacket 112 of the cooking vessel 102, the steam is made to pass through the by-pass passage (BPi). The by-pass manual valve (VBPI) is disposed in its open position by the operator in the event the inlet solenoid valve 142 malfunctions.
[0026] Similarly, regardless of the automatic and manual modes, the outlet tube manual
valve (V0), which is also a one-way valve, is always disposed in an open condition to allow the

condensate to pass downstream of the outlet tube 126. Further, irrespective of the automatic and manual modes, the by-pass manual valve (VBpo) is always disposed in its closed position by the operator so that the condensate is allowed to take the normal passage having the outlet solenoid valve 145 for draining the condensate. However, in case the outlet solenoid valve 145 malfunctions the condensate is made to drain through the by-pass passage (BPo). The by-pass manual valve (VBpo) is disposed in its open position by the operator in the event the outlet solenoid valve 145 malfunctions.
[0027] FIG. 2 shows an embodiment of the cooking vessel 102 in which a first concentric
opening 150 is formed on the outer surface 134 of the cooking vessel 102 and the jacket 112. Through the first concentric opening 150 a temperature sensing device is partially insertable inside the cooking vessel 102. Preferably, the temperature sensing device includes a Resistance Temperature Detector (RTD) 152 having a temperature sensing end 154 and securely disposed within a thermowell 156 in a manner that the temperature sensing end 154 is exposed therefrom. Alternatively, the temperature sensing device may also include a thermocouple or a thermistor and considered to be within the scope of the present invention. The thermowell 156 is partially insertable within the cooking vessel 102 through the first concentric opening 150 so as to allow the temperature sensing end 154 to be exposed inside of the cooking vessel 102. The temperature sensing end 154 measures the cooking temperature of the food items 120 when the cooking vessel 102 is in operation. As seen in FIG. 2, the RTD 152 has extension cables 158 extending therefrom and connected to the controller 146. During cooking operation, any increase or decrease in cooking temperature of food items 120, for example rice, dal or vegetable, is sensed by the temperature sensing end 154 of the RTD 152. In response to each of the measured cooking temperature, the RTD 152 generates an electrical signal and transmits to the controller 146. Further, as seen in FIG. 2, a portion 160 of the thermowell 156 exposed within the jacket 112 is covered with an insulating material 162. The insulating material 162 prevents the RTD 152 from measuring the temperature of steam present within the jacket 112. The insulating material 162 may be securely disposed within the jacket 112 in known manner.

[0028] As shown in FIG. 2, the outer surface 134 of the cooking vessel 102 and the
jacket 112 is also formed to have a second concentric opening 164 through which a temperature gauge 166 having a temperature sensing end 168 is partially insertable inside the cooking vessel 102. Preferably, the temperature gauge 166 is also securely disposed within a thermowell 169 in such a manner that the temperature sensing end 168 is exposed inside the cooking vessel 102 for measuring cooking temperature of the food items 120. A portion of the thermowell 169 that is exposed within the jacket 112 is also covered with an insulating material 162 securely disposed within the jacket 112 in known manner. The measured temperature is displayed at an opposite end 170 of the temperature gauge 166. Reading of cooking temperatures with the help of the temperature gauge 166 could be used as an alternative in case the RTD 152 malfunctions. It should however be noted that installation and usage of the temperature gauge 166 as an alternative source to measure cooking temperature along with the RTD 152 should not be construed to be limiting to the scope of the invention. In various other embodiments of the cooking vessel 102 according to the present invention, the cooking vessels may only have the RTD 152 as the only cooking temperature sensing device.
[0029] Fig. 2 also shows a third opening 172 formed on an outer surface 134 of the
cooking vessel 102 through which a pressure relief valve 174 is connected thereto. The third opening 172 allows the pressure relive valve 174 to be in fluid communication with the steam present within the jacket 112. Preferably, the pressure relief valve 174 is designed in such a manner that whenever the pressure of the steam reaches to a pressure of 4 kg/cm2 the pressure relief valve 174 opens up to release excess pressure. The release of excess pressure ensures safety of the cooking vessel 102 and its associated equipments as well that of the operator during cooking operation.
[0030] Referring back to FIG. 1, a longitudinal manually operated handle 176 is shown
to be rigidly attached to the outer surface 134 of the cooking vessel 102. When connected the handle 176 is disposed opposite to the connection of the inlet tube 124 with the cooking vessel 102. Both the handle 176 and the inlet tube 124 have connecting portions 178 that are pivotally connected to a pair of vertically oriented stands 180 of the support structure 104 in a manner shown in FIG. 1. For dispensing the cooked food items 120 from the cooking vessel 102

or for cleaning the interiors thereof the handle 176 is angularly rotated by the operator resulting in pivotal rotation of the cooking vessel 102 with respect to the support structure 104.
[0031] FIGS. 1 and 2 also show an embodiment of a control panel 148 according to the
present invention. The control panel 148 may be positioned at a distance from the cooking vessel 102 or in some other embodiments of the cooking system 100 suitably disposed at a remote location. The control panel 148 comprises of a housing 182 that has a plurality of actuable buttons that may be selectively actuated by the operator for carrying out cooking operations in a desirable manner. The housing 182 also has a plurality of indicators 184 for providing visual indication to the operator on the ON/OFF conditions of the cooking operation. As seen in FIGS. 1 and 2, the plurality of actuable buttons includes a food selector switch 186 for selecting food items 120 that could be cooked within the cooking vessel 102. The food selector switch 186 has OFF, RICE, DAL and VEGETABLES positions marked thereon. Depending on the cooking requirement the food selector switch 186 could be selectively rotated to any one of the marked positions. Further, the plurality of actuable buttons also includes a START/STOP switch 188 for starting and stopping the cooking operation, and a MODE knob 190 for carrying out operations in different modes. Similar to the food selector switch 186, the MODE knob 190 has OFF, AUTO and MANUAL positions marked thereon. Depending on the mode in which the operator wishes to operate the cooking operation, the MODE knob 190 could be selectively positioned at the respective marking.
[0032] It should however be noted that actuating the food selector switch 186 to
selectively choose between RICE, DAL and VEGETABLE food items 120 is not limiting to the scope of the present invention. According to several other embodiments of the control panel 148, the selector switch 186 may be designed in such a manner that more food items 120 could be selected. Further, according to some other embodiments of the control panel 148, the control panel 148 may have push buttons or touch buttons for selecting food items 120 or for selecting the OFF, AUTO, and MANUAL modes instead of the rotatable food selector switch 186 and MODE knob 190, respectively. All these embodiments should be construed to be within the scope of the present invention. Similar provisions could also be provided for the START/STOP switch 188.

[0033] An embodiment of a controller positioned inside the housing 182 is shown in
FIGS. 1 and 2. The controller 146 is configured to be electrically connected with the plurality of actuable buttons, the plurality of indicators 184, the RTD 152 for receiving the electrical signals, and the inlet and outlet solenoid valves 142, 145 for controlling their opening and closing operations. The controller 146 is preconfigured with a program that has a pre-stored maximum and minimum cooking temperature of food items 120 (for example- RICE, DAL, VEGETABLES) that are to be cooked within the cooking vessel 102. The program may also accommodate maximum and minimum cooking temperatures of the food items 120 other than RICE, DAL, and VEGETABLES in other embodiments of the controller 146 according to the present invention. Once the controller 146 is configured with the program, provisions are made for the operator to change the maximum and minimum temperatures in the program prior to start of the cooking operation. The controller 146 is also configured to determine an actual cooking temperature of the food item corresponding to each of the electrical signals received from the RTD 152. Further, the determined actual temperature of the food items 120 is compared with the maximum cooking temperature of that food item pre-stored in the program. The program also has a pre-stored cyclic drainage time interval of the condensate based on which the controller 146 controls the ON/OFF time of the outlet solenoid valve 145. The cyclic drainage time interval may be suitably modified depending on the drainage requirement.
[0034] In the following description working of the cooking system 100 in automatic and
manual modes will be explained. Prior to selecting the mode in which the cooking system 100 would operate, an inner area of the cooking vessel 102 is filled with water having raw food item and the lid 122 is closed. The pressure regulating valve 144 of the inlet tube 124 is appropriately set to allow the steam having a pressure of 3 kg/cm2 to pass downstream to the inlet tube 124. Once the pressure regulating valve 144 is set, the inlet tube manual valve (V|) and the outlet tube manual valve (V0) are disposed in their open positions, and the inlet tube 124 and outlet tube by-pass manual valves (VBPI) and (VBP0) are disposed in their closed positions (refer FIGS. 1 and 2).
[0035] If the cooking system 100 is desired to be operated in the automatic mode, the
operator approaches the control panel 148 and selectively positions the MODE knob 190 at the

AUTO marked position. Thereafter, the food selector switch 186 is selectively positioned at RICE, or DAL, or VEGETABLE marked positions depending on the food item that is to be cooked. The operator then actuates the START switch 188 provided on the control panel 148 and once the START switch 188 is actuated the visual indicator representing start of the operation is turned ON signalling start of the cooking operation in the automatic mode. Further, upon actuation of the START switch 188 the controller 146 receives a signal from the food selector switch 186 regarding the food item that is selected by the operator for cooking and from the MODE knob 190 as to the mode in which the cooking system 100 needs to be operated. The controller 146 transmits an electric signal to the inlet solenoid valve 142 resulting in actuation thereof in the open position.
[0036] As soon as the inlet solenoid valve 142 is disposed in the open position, the
steam having a constant flow rate and a constant pressure of 3 kg/cm2flows downstream of the inlet tube 124 to de dispensed inside the jacket 112 through the steam dispensing end 130. As the cooking process continues heat energy of the steam present within the jacket 112 is exchanged across the wall of the jacket 112 with the water and food items 120 present within the cooking vessel 102. As the temperature inside the cooking vessel 102 starts to build up, the RTD 152 senses the increase in cooking temperature and starts generating electrical signals responsive to the measured cooking temperature. In a progressive manner, the electrical signals are received by the controller 146 that determines actual cooking temperatures corresponding to each of the received electrical signals and may display of a screen (not shown) of the controller. The controller 146 then compares the actual temperature with the maximum and minimum pre-stored cooking temperature of the cooked food item pre-stored in the program.
[0037] As the cooking operation progresses and the cooking temperature inside the
cooking vessel 102 increases, the controller 146 eventually identifies that the actual cooking temperature has reached to a value equal to the prestored maximum cooking temperature of the cooked food item. Instantly, the controller 146 sends a signal to the inlet solenoid valve 142 so that the solenoid valve is disposed in the closed position resulting in stoppage of further inflow of steam within the jacket 112 and indicating that the food item has been cooked.

Simultaneously, the controller 146 also allows the outlet solenoid valve 145 to be disposed in the closes position and automatically stops entire cooking operation. Alternatively, the operator may also intermittently stop the entire cooking operation by actuating the STOP switch 188. Instantly, the visual indicator representing the operation being stopped is turned ON signalling stoppage of the cooking operation in the automatic mode.
[0038] If the cooking system 100 is desired to be operated in the manual mode, the
operator selectively positions the MODE knob 190 at the MANUAL marked position. The operator then actuates the START switch 188 provided on the control panel 148 and once the START switch 188 is actuated the visual indicator representing start of the operation is turned ON signalling start of the cooking operation in the manual mode. Upon actuation of the START switch 188 the controller 146 receives a signal from the MODE knob 190 regarding the manual mode in which the cooking system 100 needs to operate. The controller 146 transmits an electric signal to the inlet solenoid valve 142 resulting in actuation thereof in the open position. It is to be noted that in the manual mode the controller 146 is configured in such a manner that there is no electrical communication established between the controller 146 and the RTD 152.
[0039] As soon as the inlet solenoid valve 142 is disposed in the open position, the
steam having a constant flow rate and a constant pressure of 3 kg/cm2 flows downstream of the inlet tube 124 and dispensed inside the jacket 112. As the process continues heat energy of the steam present within the jacket 112 is exchanged across the wall of the jacket 112 with the water and food items 120 present within the cooking vessel 102. As the cooking operation progresses, the operator could either identify manually, or by reading the temperature reading of the additional temperature gauge 166 whether the food item is cooked or still uncooked. Upon ascertaining that the food item is cooked, the operator actuates the STOP switch 188 provided on the control panel 148 to stop the cooking operation. At this point, the visual indicator representing the operation being stopped is turned ON signalling stoppage of the cooking operation in the manual mode. Upon actuating the STOP switch 188 the controller 146 disposes the inlet solenoid valve 142 and the outlet solenoid valve 145 in the closed position and the entire cooking system 100 is stopped.

[0040] A skilled person in the art would appreciate that the above noted several
embodiments of the present invention offers a mechanism by which only the desired amount of steam that is actually required for cooking is dispensed within the cooking vessel 102. The embodiments of the present invention therefore offer significant advantage over the prior art cooking systems that have unnecessary inflow of steam within the cooking vessel 102 for cooking of food items 120. As such, in the embodiments of the present invention, appropriate consumption of steam takes place leading to the overall efficiency of the cooking system 100. The cooking system complementing the above referred advantages could also be easily installed and used for mass scale cooking of food items.
[0041] As noted above, the program of the controller 146 also has the pre-stored cyclic
drainage time interval of the condensate based on which the controller 146 controls the ON/OFF time of the outlet solenoid valve 145. Irrespective of the automatic or manual mode in which the cooking system 100 may operate, the controller 146 periodically sends signals to the outlet condensate valve for being disposed in the open position resulting in drainage of the condensate through the condensate dispensing end 138 thereof. The controller 146 is also configured to dispose the inlet solenoid valve 142 from the open position to the closed position to prevent inflow of the steam within the cooking vessel 102 whenever the outlet solenoid valve 145 is disposed in the open position. Periodic drainage of the condensate from the cooking vessel 102 helps in better heat exchange of the steam present within the jacket 112 with the food items 120 present inside the cooking vessel 102 thereby increasing the efficiency of the cooking system 100.
[0042] It is to be noted that the controller 146, which is disposed inside control panel
148, and referred in several embodiments should not be construed to be limiting. In various other embodiments of the control panel 148 instead of the controller 146 Programmable Logic Controller (PLC) or microcontroller may also be used. Further, in several other embodiments of the present invention instead of having the cooking vessel 102 with the jacket 112, the cooking vessel 102 without a jacket 112 could also be used for the purpose of cooking of food items 120. In such cooking vessels steam could be directly dispensed within the vessel. Additionally, in several other embodiments of the present invention instead of using only one cooking vessel

multiples cooking vessels that are electrically coupled with the controller could also be used. All such embodiments should be construed to be within the scope of the present invention.
[0043] It will be apparent to those skilled in the art that various modifications and
variations can be made to the present invention without departing from the spirit and scope of the invention. Thus it is intended that the present invention cover the modifications and variations of this invention provided they come within the scope of the appended claims and their equivalents.

We Claim:
1. A steam based cooking system comprising:
a cooking vessel including an inlet tube, an outlet tube, and a temperature sensing device partially insertable within the cooking vessel for measuring internal cooking temperature when the food items are cooked and generating electrical signals responsive to the measured cooking temperature;
an inlet solenoid valve connected to the inlet tube, the inlet solenoid valve when operable in an open position allowing steam receivable from a steam generating source to enter the cooking vessel and when operable in a closed position preventing the steam from entering the cooking vessel;
an outlet solenoid valve connected to the outlet tube, the outlet solenoid valve when operable in an open position allowing drainage of a condensate from the cooking vessel and when operable in a closed position preventing drainage of the condensate; and
a controller communicatively coupled to the inlet and outlet solenoid valves for controlling their opening and closing, the controller communicatively coupled to the temperature sensing device for receiving the electrical signals and determining an actual cooking temperature corresponding to each of the electrical signal, the controller configured to:
compare each of the determined actual cooking temperature with a pre-stored maximum temperature of the food item, and disposes the inlet solenoid valve from the open position to the closed position if the actual cooking temperature exceeds the pre-stored maximum cooking temperature; and
periodically dispose the outlet solenoid valve from the closed position to the open position based on a pre-stored drainage time interval.
2. The steam based cooking system according to claim 1, wherein the controller is configured
with a program that has pre-stored maximum and minimum temperature of food items that are
to be cooked within the cooking vessel, and wherein the program has a pre-stored cyclic
drainage time interval for periodically draining the condensate. *

3. The steam based cooking system according to claim 1, wherein the controller is configured to dispose the inlet solenoid valve from the open position to the closed position to prevent inflow of the steam within the cooking vessel when the outlet solenoid valve is disposed in the open position.
4. The steam based cooking system according to claim 1, wherein the controller is either a Programmable Logic Controller (PLC) or a microcontroller.
5. The steam based cooking system according to claim 1, wherein the steam based cooking system further includes a control panel, the control panel comprising a food selector switch for selecting food items for cooking, an ON/OFF switch for starting and stopping the cooking operation, and a MODE knob for carrying out operations in auto and manual modes, and wherein the controller is positioned inside the control panel.
6. The steam based cooking system according to claim 1, wherein the cooking vessel further includes an elongated jacket formed around an inner surface of the cooking vessel in spaced apart relationship and having a sealed top end, and wherein an end of the inlet tube is insertable within the jacket through a first opening formed on an outer surface of the cooking vessel for allowing steam to be dispensed within the jacket.
7. The steam based cooking system according to claim 6, wherein the outer surface of the cooking vessel and the jacket are formed to have a first concentric opening and the temperature sensing device is partially insertable inside the cooking vessel through the first concentric opening, and wherein portion of the temperature sensing device exposed within the jacket is covered with an insulating material securely disposed within the jacket.
8. The steam based cooking system according to claim 7, wherein the temperature sensing device includes a Resistance Temperature Detector (RTD) having a temperature sensing end,

the RTD securely disposed within a thermowell in a manner that the temperature sensing end is exposed therefrom, and wherein the temperature sensing end is exposed to the interior of the cooking vessel when the thermowell is partially insertable within the cooking vessel for measuring cooking temperature of the food items.
9. The steam based cooking system according to claim 6, wherein the outer surface of the
cooking vessel and the jacket are formed to have a second concentric opening, a temperature
gauge having a temperature sensing end is partially insertable inside the cooking vessel from
outside through the second concentric opening in a manner that the temperature sensing end
is exposed to the interior of the cooking vessel for measuring cooking temperature of the food
items , and wherein portion of the temperature gauge exposed within the jacket is covered
with an insulating material securely disposed within the jacket.
10. The steam based cooking system according to claim 1, wherein an outer surface of the
cooking vessel includes a second opening to which a pressure relief valve is operably
connected.