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Money saving, Energy conservation
and green environmental protection are so closely related to our
lives that we are obliged to pay much attention to them. The
concept of "off fire reboiling", a concept concerning the modern
eco-friendly cooking utensil [1], was born
in 1987.
Ordinary cooking utensils are energy-wasteful, especially
stewing pots. During preparation of foods such as rice, porridge,
meat, soup or vegetables, the content of the pot is usually
heated to boiling point and then allowed to stew or simmer on the
stove for a considerably long time, using up fuel to do so.
However, once boiling temperature is reached, the temperature
within the pot does not actually rise beyond that. Instead, the
energy wasted is used just to offset the heat lost (through
evaporation, conduction, convection) in order to maintain the
cooking pot at a sufficiently high temperature. In fact the pot
can be kept boiling without using heat energy if there is no such
heat loss! Why not create a heat insulated pot that can reboil
without consuming more heat energy?
Based upon the above observed fact, Zhiliang Wan(万之樑), the
inventor of "off fire reboiling pots", made two inventions and
applied for two patents during 1986-1988, one of which was named
《daily thermal insulated energy-saving cooking
utensils》[2](patent number:
CN86207669), the other was named 《utility energy-saving timesaving regenerative
and thermal insulated cooking utensils》[3](patent number: CN1042062).
Both patents are now public free technologies except
unpublished part, the specifications can be searched out (by
patent numbers) and read in detail (in Chinese language) on the
website of The State Intellectual Property Office Of
P.R.C. The information also can be found out by Google search.
In the patent of 《daily thermal insulated energy-saving cooking
utensils》, Zhiliang Wan propounded for the first time the
concept of "thermal insulated energy saving heating utensil" and
its overall design -- a thermal insulating envelope to be added
outside the body of the pot.
The "thermal insulated stewing pots"[4]
made in Japan, Taiwan and the mainland of China since the late
1990s are fundamentally in accordance with the specification of
this patent.
In the patent of 《utility energy-saving timesaving regenerative
and thermal insulated cooking utensils》, Zhiliang Wan further
propounded the creative concept and implementary plan of "heat
conservation and thermal insulation → off fire reboiling".
The significant innovation in this patent lay in: On the
basis of adding a thermal insulating envelope outside the body of
the conventional pot, a disc-shaped heat reservoir is installed
beneath the metal base of the thermally insulated pot. The heat
reservoir conserved heat energy during the heating process on the
stove and resupplied heat energy for the pot to make up for the
slight heat loss and keep it continuously reboiling after it
being taken off the cooking stove.
The current popular "off fire reboiling pots"[5] are fundamentally in accordance with the
specification of this patent.
Today the "off fire reboiling pots", "self-reboiling pots"
and "fire-free reboiling pots" on the market are various in
brands, types, and processing techniques, they are all built on
the same core concept elucidated in the above-mentioned two
patents.
[1] There is almost no heat loss and 35-55% of
heat energy can be saved by using this sort of cooking
utensil.
[2] daily thermal insulated energy-saving cooking utensils = 保温节能型日用加热器皿
[3] utility energy-saving timesaving regenerative and thermal
insulated cooking utensils = 蓄热保温节能省时省力多用型日用加热器皿
[4] thermal insulated stewing pots = 焖烧锅
[5] "off fire reboiling pots", "self-reboiling pots" or
"fire-free reboiling pots" = 免火再煮锅, 停火再煮锅 or 离火续煮锅
◎
(This article is for clarifying some facts only, in no way for boasting.)
Pot's Type
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Gas used up for Porridge cooking
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Gas used up for Rice cooking
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Gas used up for Meat cooking
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Gas used up for Soup cooking
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Usual Pot
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150L (80L for boiling
and 70L for simmering)
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140L (80L for boiling
and 60L for simmering)
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170L (80L for boiling
and 90L for simmering)
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150L (80L for boiling
and 70L for simmering)
|
OFR Pot
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90L (90L for boiling
and 0L for simmering)
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88L (88L for boiling
and 0L for simmering)
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92L (92L for boiling
and 0L for simmering)
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90L (90L for boiling
and 0L for simmering)
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Gas saved up for Porridge cooking
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Gas saved up for Rice cooking
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Gas saved up for Meat cooking
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Gas saved up for Soup cooking
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40%
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37%
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46%
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40%
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◎ 1 L=1 cubic decimeter; room
temperature: 15℃; pot's size: ø=22cm height=20cm; contents: 2.2L
A Translated Quotation from
the Specification of Patent-CN88100492.8(page 3, line 10 to
22):
"The present invention's aim is
achieved by the following method: Beneath the metal bottom of the
"daily thermal insulated energy-saving cooking utensil", a
disc-shaped heat reservoir is installed, which is made of a
special refractory material with excellent heat storage
performance. When the utensil is placed on the stove being
heated, the disc-shaped heat reservoir located beneath the
utensil's bottom is heated up and starts to store heat energy, as
the food in the utensil is heated up to boiling point, the heat
reservoir has already stored a significant quantity of heat
energy. Now the utensil can be taken away from the cooking stove
and put on the thermal insulated base, the heat reservoir beneath
the utensil's bottom will release its stored heat energy slowly.
In the first tens of minutes, the pot can be maintained at
boiling point temperature, while afterwards it can be maintained
above 85℃ for several hours.
The fact proved: If we want our food to be thoroughly cooked
by stewing, we needn't keep it continuously ebullient on the
stove, but just keep it under a certain high temperature close to
100? and let it go through a period of time.
Therefore, by means of the above-mentioned design, this
invention has achieved its aim through successfully appending the
heat-regenerative performance to the "daily thermal insulated
energy-saving cooking utensil" and thus making it has the special
function to continuously heat up and turn raw or deficiently
cooked food into thoroughly cooked food after the cooking utensil
has been taken off from the cooking stove. "
* Because the pot can be taken off from the cookstove as
soon as it reaches boiling point, and there is almost no heat
loss throughout the whole stewing process, 35-55% of heat energy
can be saved. It is especially suitable for stewing rice,
porridge, meat, soups, vegetables, etc.
Furthermore, by taking advantage of the pot's excellent
performance of thermal insulation, every morning before your
going to work you may just heat your meat or soup to boiling
point and then let the utensil itself simmer the food for you,
you'll be happy to enjoy the warm and thoroughly cooked meat or
soup when you come back home from work in the evening. All this
is fulfilled without any energy costs! |
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