Note: Descriptions are shown in the official language in which they were submitted.
WO 2023/002257
PCT/IB2022/051400
An Inner Pot Assembly, a Cooking Utensil, and a Control Method of the Cooking
Utensil
Field of the Invention
The present invention relates to the technical field of kitchen utensils and
in particular
relates to an inner pot assembly, a cooking utensil, and a control method of
the cooking
utensil.
Background of the Invention
Currently, in existing low-sugar rice cookers, the top outer border of a
steamer basket is
supported on the top outer border of an inner pot, and a water passing
cylinder is provided
below the steamer basket. The bottom of the water passing cylinder is spaced
apart from
the inner surface of the inner pot and is provided with a structure with
openings. Water in
the inner pot, after being heated, can rise into the steamer basket via the
water passing
cylinder, so as to rinse rice accommodated in the steamer basket. However,
rice cookers
with this type of structure have a limited pressure at the inner side of the
water passing
cylinder, which results in poor water rising and therefore non-ideal sugar
lowering effects.
In view of this, the present invention provides an inner pot assembly, a
cooking utensil,
and a control method of the cooking utensil, so as to at least partially solve
the problem in
the prior art.
Summary of the Invention
A series of concepts in simplified form have been introduced in the Summary of
the
Invention section, which will be described in further detail in the Detailed
Description
section. The Summary of the Invention section of the present invention is not
intended to
limit the key features and essential technical features of the claimed
technical solutions,
nor is it intended to define the scope of protection of the claimed technical
solutions.
In order to at least partially solve the above-described problem, according to
a first aspect
of the present invention, an inner pot assembly for a cooking utensil is
disclosed,
comprising:
- an inner pot having a height of [90, 200] mm; and
- a steamer basket supported in the inner pot and removable therefrom,
comprising a
bottom wall and a side wall connected with the bottom wall, the bottom wall
and the side
wall enclosing an accommodating chamber for accommodating rice, the steamer
basket is
fitted to the inner pot so that a receiving space is formed between the bottom
wall and the
inner pot, or between the bottom wall, the side wall, and the inner pot,
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the bottom wall comprising a water rising part, a guiding part extending
outward from an
outer border of the water rising part, and a water descending part extending
outward from
an outer border of the guiding part, the water rising part being arranged
higher than the
water descending part, rice being accommodated on the water rising part, the
guiding part,
and the water descending part,
the water rising part being provided with a plurality of first through holes
communicating
the accommodating chamber with the receiving space and allowing water, but not
rice, to
pass through, the water descending part being provided with a plurality of
second through
holes communicating the accommodating chamber with the receiving space and
allowing
water, but not rice, to pass through, and the guiding part being a water-
impermeable zone
extending from the outer most border of the first through holes to the inner
most borders of
the second through holes,
a maximum height difference between the water rising part and the water
descending part
being H1, and a height difference between any one of the first through holes
and any one
of the second through holes being H2,
wherein, 3 mm H1 40 mm, and/or 3 mm H2 40 mm, so that during cooking, boiling
water in the receiving space is able to enter the accommodating chamber via
the first
through holes.
The inner pot assembly according to the present invention defines the guiding
height of
the guiding part by defining the height difference between the water rising
part and the
water descending part or the height difference between the first through holes
and the
second through holes so that an appropriate pressure is formed in the space
enclosed by
the guiding part by water vapor, gas, and air bubbles after water starts
boiling. Such
pressure enables boiling water in the receiving space to enter the steamer
basket via the
first through holes and rush through the upper surface of rice, then spread
from the middle
to the surrounding, and finally fall back into the inner pot via the second
through holes or
the first through holes. The water can soak and rinse all the rice and thus
effectively
ensure a sugar lowering effect and the flavor of the rice.
By fitting the steamer basket to the inner pot, a receiving space is formed
between the
bottom wall of the steamer basket and the inner port, or between the bottom
wall, the side
wall of the steamer basket, and the inner pot, i.e., a sealed or quasi-sealed
chamber is
formed between the steamer basket and the inner pot. There are three zones
capable of
pressure relief in the receiving space, i.e., the location of fitting between
the steamer
basket and the inner pot, the first through holes, and the second through
holes. As there is
no gap or only a tiny gap at the location of fitting between the steamer
basket and the
inner pot, boiling water inside the receiving space will encounter a higher
resistance in that
zone than at the first through holes and the second through holes. Therefore,
it is less
possible for boiling water inside the receiving space to pass through the
location of fitting,
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and even if boiling water passes through the location of fitting, the quantity
will be
relatively small and its impact on the water rising effect at the first
through holes will be
limited.
When water inside the receiving space is heated to a certain temperature, gas
and air
bubbles can be generated. Air bubbles rise to the surface of the water and
generate a
pressure in the receiving space as gas increases. VVhen water is heated to
boil, boiling air
bubbles emerge with water out of the water surface under the effect of the
pressure and
can accumulate at the inner side of the bottom of the guiding part. As the
first through
holes are higher than the second through holes, when rice is placed in the
accommodating chamber of the steamer basket, the thickness of rice placed at
the first
through holes will be smaller than that of rice placed at the second through
holes, so that
the resistance of rice encountered by water at the first through holes is
smaller than that
encountered at the second through holes. The sum of potential energy of the
resistance of
rice grains encountered at the first through holes by water and air bubbles in
the receiving
space and their own gravity is smaller than the sum of potential energy of the
resistance of
rice grains encountered at the second through holes by water and air bubbles
and their
own gravity. Therefore, under the effect of the pressure, water and air
bubbles in the
receiving space are able to rise to the accommodating chamber of the steamer
basket via
the first through holes provided at the water rising part, and, in the
accommodating
chamber, soak and rinse rice in the steamer basket. Then, starch and sugar
contents in
the rice in the steamer basket can fall back into the receiving space via the
second
through holes and the first through holes, thus achieving the objective of
lowering sugar in
rice and preventing rice from being partially cooked. It can be understood
that there may
be a small quantity of boiling water that enters the steamer basket via the
second through
holes, but its quantity will be so small that it will only have very limited
impact on the water
rising effect of the first through holes.
By providing the water rising part, the guiding part, and the water descending
part on the
bottom wall, and with rice being accommodated on the water rising part, the
guiding part,
and the water descending part, water admitting and water discharging of the
steamer
basket can be directly achieved by the bottom wall which supports rice. This
structure is
very simple and cost-saving. In addition, as water rushes into the steamer
basket via the
bottom wall, i.e., from below rice grains, it can stir the rice grains from
below so that the
rice grains are rolled and thus providing a better rinsing effect of the rice
grains.
Optionally, 8 mm H1 30mm, and/or 8 mm H2 30 mm.
Optionally, 10 mm < H1 20mm, and/or 10 mm < H2 <20 mm.
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In the inner port assembly according to the present invention, the height
difference
between the water rising part and the water descending part or the height
difference
between the first through holes and the second through holes can be further
optimized so
that the sugar lowering effect and flavor of the rice are still improved.
Optionally, the water rising part comprises any one of a plane, a curved face
or a
combination thereof.
With the inner port assembly according to the present invention, the shape of
the water
rising part can be flexibly designed.
Optionally, the area of the projection of the water rising part on a
horizontal plane is equal
to or larger than 80 mm2.
The inner port assembly according to the present invention can ensure that the
water
rising part has enough area for providing water rising holes and thus ensure
the sugar
lowering effect and flavor of rice.
Optionally, the water descending part comprises any one of a plane, a curved
face or a
combination thereof.
With the inner port assembly according to the present invention, the shape of
the water
descending part can be flexibly designed.
Optionally, the bottom wall is rotationally symmetric with the central axis of
the steamer
basket as rotation axis.
With the inner port assembly according to the present invention, the bottom
wall has a
regular shape and is easy to process.
Optionally, the guiding part comprises any one of a cylindrical side face, a
truncated cone
side face, or an arc-shaped face, or any combination thereof.
With the inner port assembly according to the present invention, the shape of
the guiding
part can be flexibly designed.
Optionally, a top part of the guiding part and a bottom part of the guiding
part are both
horizontal planes and are connected by a revolution face in the form of a side
face of a
truncated cone.
With the inner port assembly according to the present invention, the guiding
part is
designed to be in the form of a side face of a truncated cone, so that the
steamer basket is
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easy to process.
Optionally, the water rising part is a horizontal plane, and/or the water
descending part is a
horizontal plane.
With the inner port assembly according to the present invention, the bottom
wall is
designed to present an upward protrusion in the form of a truncated cone, so
that the
steamer basket is easy to process and produce.
Optionally, when the steamer basket is placed in the inner port, an inner
surface of the
inner pot is in contact with the steamer basket so that the steamer basket is
fitted to the
inner pot by contact, wherein, the inner surface of the inner pot is provided
with an
arc-shaped structure, a bevel structure, an inward protruding structure, or a
step structure
extending towards the inside of the inner pot, so as to come into contact with
and support
the steamer basket.
In the inner pot assembly according to the present invention, the inner pot is
configured to
support the steamer basket, which has a simple and compact structure and makes
it
convenient to produce, use, and maintain the product. At the same time, with
the steamer
basket in contact with the inner pot, after water starts boiling, water vapor,
gas, and air
bubbles in the receiving space can concentrate as much as possible at the
guiding part,
generating a sufficient pressure at the guiding part and ensuring water rising
effects.
Optionally, an outer surface of the steamer basket is provided with a sealing
member
extending circumferentially that comes into contact with the inner pot when
the steamer
basket is placed in the inner pot, so that the steamer basket is tightly
fitted to the inner pot.
In the inner pot assembly according to the present invention, the steamer
basket is in
sealing contact with the inner pot, which better limits the pressure relief at
the location of
fitting and thus better ensures the water rising at the water rising part.
Optionally, an inner surface of the inner pot is provided with an inward
protruding rib
extending circumferentially, when the steamer basket is placed in the inner
pot, the
distance between the inward protruding rib and an outer surface of the steamer
basket
being smaller than or equal to 1 mm, so that the steamer basket is fitted to
the inner pot by
proximity; or
an outer surface of the side wall of the steamer basket is provided with an
outward
protruding rib extending circumferentially, when the steamer basket is placed
in the inner
pot, the distance between the outward protruding rib and an inner surface of
the inner pot
being smaller than or equal to 1 mm, so that the steamer basket is fitted to
the inner pot by
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proximity.
With the inner pot assembly according to the present invention, the steamer
basket
contacts or approaches the inner pot as much as possible so that after water
starts boiling,
water vapor, gas, and air bubbles in the receiving space concentrate as much
as possible
at the guiding part, generating a sufficient pressure at the guiding part and
ensuring the
water rising through the first through holes.
It has been demonstrated by experiments that, when the distance between the
inner pot
and the steamer basket at the location of fitting is not larger than 1 mm, the
pressure relief
at the location of fitting can be effectively controlled so that after water
starts boiling, water
vapor, gas, and air bubbles in the receiving space concentrate as much as
possible at the
guiding part and generate a sufficient pressure at the guiding part, thus
ensuring the water
rising through the first through holes.
Optionally, the steamer basket is fitted to the inner pot by contact or by
proximity at a
location of fitting, and the distance between the steamer basket and the inner
pot at the
location of fitting is equal to or smaller than 1 mm.
With the inner pot assembly according to the present invention, the steamer
basket
contacts or approaches the inner pot as much as possible so that the receiving
space
forms a sealed or quasi-sealed space, and after water starts boiling, water
vapor, gas, and
air bubbles in the receiving space concentrate as much as possible at the
guiding part,
generating a sufficient pressure at the guiding part and ensuring the water
rising through
the first through holes.
It has demonstrated by experiments that, when the distance between the inner
pot and the
steamer basket at the location of fitting is not larger than 1 mm, the
pressure relief at the
location of fitting can be effectively controlled so that after water starts
boiling, water vapor,
gas, and air bubbles in the receiving space concentrate as much as possible at
the
guiding part and generate a sufficient pressure at the guiding part, thus
ensuring the water
rising through the first through holes.
Optionally, the location of fitting is not higher than the top of the water
rising part.
With the inner pot assembly according to the present invention, the location
of fitting
between the inner pot and the steamer basket is as low as possible so as to
effectively
control the pressure relief at the location of fitting, ensuring that a
sufficient pressure is
generated at the guiding part and ensuring the water rising through the first
through holes.
Optionally, the maximum distance H3 between the location of fitting and the
top of the
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water rising part in the vertical direction is such that 1 H1/H3 < 15.
With the inner pot assembly according to the present invention, the location
of fitting
between the inner pot and the steamer basket is as low as possible so as to
effectively
control the pressure relief at the location of fitting, ensuring that a
sufficient pressure is
generated at the guiding part and ensuring the water rising through the first
through holes.
Optionally, the plurality of first through-holes are uniformly distributed,
and/or the plurality
of second through holes are uniformly distributed along the circumferential
direction of the
water descending part.
With the inner pot assembly according to the present invention, the first
through holes and
the second through holes are uniformly distributed, so that rice can be soaked
and rinsed
uniformly.
Optionally, the steamer basket is made of metal, wood material, or plastic
material,
wherein, the steamer basket is integrally formed, or its bottom wall is
integrally formed.
With the inner pot assembly according to the present invention, the steamer
basket has a
wide range of material choices and is simple to process.
Optionally, the steamer basket further comprises a holding part extending
circumferentially from the top of the side wall and being depressed towards
the central
axis of the steamer basket relative to the side wall, and/or the side wall is
provided with a
plurality of side wall through holes provided in a spaced manner along the
circumferential
direction of the steamer basket and located higher than the location of
fitting between the
steamer basket and the inner pot.
With the inner pot assembly according to the present invention, the holding of
the steamer
basket by a user is facilitated thanks to the holding part. By providing side
wall through
holes at a location above the location of fitting between the steamer basket
and the inner
pot, excessive water and foams in the steamer basket can be discharged into
the inner
pot via the side wall through holes, thus reducing the possibility of
overflowing from the
pot.
Optionally, an inner surface of the inner pot is provided with at least one
water level line,
when the steamer basket is placed in the inner pot, at least one inner pot
water level line is
lower than the second through holes, and/or at least one water level line is
lower than the
first through holes but not lower than the second through holes.
With the inner pot assembly according to the present invention, by providing a
water level
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line, a user can be instructed to add an appropriate amount of water based on
the quantity
of rice. For a water level line below the second through holes, the water
level should be
set lower than the second through holes so that rice will not be soaked in
water, which can
not only ensure the uniformity of rice flavor, but also prevent rice from
turning bad when
being soaked for a long time during a reservation function. The water level
line can also be
lower than the first through holes but not lower than the second through
holes, which can
instruct a user to add an appropriate amount of water based on needs. For
example, when
the quantity of rice is relatively large, it can ensure that more water enters
the steamer
basket to rinse the rice. When there is only one water level line, the water
level line can be
provided according to actual need, either at a location below the second
through holes, or
at a location lower than the first through holes but not lower than the second
through holes.
When there are a plurality of water level lines, some of them can be arranged
lower than
the second through holes and some of them lower than the first through holes
but not
lower than the second through holes, so as to satisfy cooking needs of
different quantities
of rice. For example, when cooking one cup of rice (approximately 150 g), the
water level
line is below the second through holes, because only a small amount of water
is needed
for rinsing the rice and satisfying cooking needs. When cooking multiple cups
of rice, the
water level line can be at a location higher than the second through holes but
lower than
the first through holes, so that there is a sufficient amount of water to
ensure rice rising
and cooking effects for a large quantity of rice. It can be understood that
the water level
lines can also be all lower than the second through holes, or all lower than
the first through
holes but not lower than the second through holes. Various forms of water
level lines can
be flexibly provided according to needs.
Optionally, at least one water level line is lower than the second through
holes and has a
height difference with the second through holes which is smaller than or equal
to 10 mm.
With the inner pot assembly according to the present invention, at least some
or all of
water level lines are lower than the second through holes, and their height
difference with
the second through holes is larger than 0 but smaller than or equal to 10 mm,
which can
prevent rice from being soaked by water and allowing water to be heated to
boil quickly
and to execute the step of rinsing more quickly, and at the same time,
ensuring water
rising through the first through holes.
Optionally, the area of the projection of the bottom wall on a horizontal
plane is [11000,
46000] mm2, and/or the area of the guiding part is equal to or larger than 700
mm2, and/or
the volume of the receiving space is [200,2000] ml.
In the inner pot assembly according to the present invention, structural
parameters are
appropriately set so as to ensure that the receiving space can receive
sufficient water and
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the water can effectively rise at the water rising part.
A second aspect of the present invention provides a cooking utensil comprising
the inner
pot assembly described above and heating means for heating the inner pot
assembly.
The cooking utensil according to the present invention defines the guiding
height of the
guiding part by defining the height difference between the water rising part
and the water
descending part or the height difference between the first through holes and
the second
through holes so that an appropriate pressure is formed in the space enclosed
by the
guiding part by water vapor, gas, and air bubbles after water starts boiling.
Such pressure
enables boiling water in the receiving space to enter the steamer basket via
the first
through holes and rush through the upper surface of rice, then spread from the
middle to
the surrounding, and finally fall back into the inner pot via the second
through holes or the
first through holes. The water can soak and rinse all the rice and thus
effectively ensure a
sugar lowering effect and the flavor of the rice.
Optionally, the nominal power P of the heating means is such that 600W P
1500W.
The cooking utensil according to the present invention sets an appropriate
nominal power,
which not only ensures that water inside the receiving space quickly boils to
produce
sufficient water vapor, gas and air bubbles, but also controls the product's
development
costs and use-costs.
A third aspect of the present invention provides a control method of a cooking
utensil,
which can be applied to the cooking utensil described above, the control
method
sequentially comprising the following processes:
a preheating process in which the heating means is controlled to heat the
inner pot
assembly so that the temperature of the inner pot rises;
a rice rinsing and cooking process in which the heating means is controlled to
intermittently heat the inner pot assembly so that water inside the receiving
space rises
and enters the accommodating chamber via the first through holes and the water
that has
entered the accommodating chamber, after soaking and rinsing the rice, falls
back into the
receiving space via the first through holes and/or the second through holes;
a rice steaming process in which the heating means is controlled to heat the
inner pot
assembly.
According to the control method of the present invention, in the rice rinsing
and cooking
process, water inside the receiving space boils, and under the effect of the
guiding part,
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water vapor, gas, and air bubbles enter the accommodating chamber via the
first through
holes and rush through the upper surface of rice, and then water spreads from
the middle
to the surrounding to soak and rinse the rice so that starch and sugar
contents in the rice
fall into the inner pot with the water. Thus, the objective of lowering sugar
can be achieved,
and the rice has a uniform flavor and is not partly uncooked.
Optionally, the cooking utensil further comprises a temperature sensor for
detecting the
temperature in a cooking space, and in the preheating process, when the
temperature
sensor detects that the temperature inside the cooking space reaches a preset
temperature T, the control method proceeds to the rice rinsing and cooking
process, the
1(:) preset temperature T being such that 65 C T 90 C.
Optionally, the preset temperature T is such that 65 C <T 80 C.
According to the control method of the present invention, food materials are
first
preheated. In the preheating process, rice can be soaked by water vapor so
that rice can
uniformly absorb water, ensuring the flavor of cooked rice.
Optionally, in the rice rinsing and cooking process, rice is rinsed multiple
times, and during
each rinsing, the heating means performs heating for a first preset duration
and then stops
heating for a second preset duration, when the number of times of rinsing
reaches N, or
when the duration of the rice rinsing and cooking process reaches a preset
rinsing
duration, the control method proceeds to the rice steaming process, wherein, N
is a
natural number.
According to the control method of the present invention, rice is rinsed
multiple times in
the rice rinsing and cooking process while being fully soaked by water, so
that the sugar
lowering effect and flavor of the rice are better.
Optionally, the heating means is an electromagnetic heating element, the first
preset
duration is [5, 25] s, and the second present duration is [10, 35] s, wherein,
N is a natural
number larger than or equal to 8 but smaller than or equal to 12, and/or the
preset rinsing
duration is [10, 30] minutes.
Optionally, the heating means is a heating plate, the first preset duration is
[7, 28] s, and
the second present duration is [8, 25] s, wherein, N is a natural number
larger than or
equal to 18 but smaller than or equal to 30, and/or the preset rinsing
duration is [5, 15]
minutes.
With the control method according to the present invention, the heating means
can be
different hardware parts and the operational parameters of the rice rinsing
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process are set based on the specific hardware performance so as to achieve
the effect of
lowering sugar and a uniform flavor of the rice.
Optionally, the heating power during the preheating process is higher than
that of the rice
steaming process, and the heating power during the rice rinsing and cooking
process is
higher than that of the rice steaming process.
The control method according to the present invention appropriately sets the
heating
power of each cooking stage, so as to effectively ensure the sugar lowering
and uniform
flavor of the rice. In the preheating process, a relatively high heating power
is used, which
can make the rice soaked as much as possible by water vapor and help ensure a
uniform
flavor of cooked rice. In the rice rinsing and cooking process, a relatively
high heating
power is used, which can make the water inside the receiving space boil to
produce
sufficient water vapor, gas, and air bubbles, so as to generate a sufficient
pressure at the
guiding part to ensure water rising and achieve the sugar lowering and uniform
flavor of
rice. After rice has been fully soaked and rinsed, in the rice steaming
process, there is no
longer need to have a large quantity of water enter the steamer basket, and
the heating
power can be lowered to save energy.
Optionally, the control method further comprises a rice braising process and
when the
duration of the rice steaming process reaches a preset rice steaming duration,
the control
method proceeds to the rice braising process, wherein, the heating power of
the rice
braising process is lower than that of the rice steaming process.
According to the control method according of the present invention, in the
rice braising
process, the heating power can be further lowered to save energy. At the same
time,
water inside the receiving space is prevented from being dried out and the
degree of
gelatinization of rice is not increased.
Description of the Drawings
The accompanying drawings of the present invention listed below constitute
part of the
present application for understanding the present invention. In the
accompanying
drawings, examples of embodiments of the present invention and their
description are
illustrated to explain the principle of the present invention.
In the accompanying drawings:
Fig. 1 is a sectional view of a partial structure of a cooking utensil
according to a preferred
embodiment of the present invention;
Fig. 2 is a sectional view of the inner pot assembly of the cooking utensil
shown in Fig. 1;
Fig. 3 is a view in perspective of the steamer basket of the inner pot
assembly shown in
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Fig. 2;
Fig. 4 is a top view of the steamer basket shown in Fig. 3;
Figs. 5 to 11 are sectional views of the inner pot assembly of a cooking
utensil according
to some embodiments of the present invention;
Fig. 12 is a top view of the steamer basket of the inner pot assembly of a
cooking utensil
according to a specific embodiment of the present invention;
Fig. 13 is a sectional view of the inner pot assembly of a cooking utensil
according to a
specific embodiment of the present invention;
Fig. 14 is a top view of the steamer basket of the inner pot assembly shown in
Fig. 13; and
Figs. 15 to 18 are sectional views of the inner pot assembly of a cooking
utensil according
to specific embodiments of the present invention.
Description of references:
100: cooking utensil
10: pot body
20: lid body
30: inner pot assembly
40: inner pot
41: flange
42: inward protruding part
43: step part
43A: step face
44: inward protruding rib
50: steamer basket
51: bottom wall
52: side wall
52A: sealing element
53: water descending part
54: water rising part
55: upper edge
56: guiding part
57: first through hole
58: second through hole
59: supporting part
60: receiving space
65: guiding chamber
61: holding part
62: side wall through hole
70: heating means
80: temperature sensing assembly
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A: central axis of the steamer basket
: outer diameter of the guiding part / inner diameter of the water descending
part
D2: maximum outer diameter of the bottom wall of the steamer basket
D3: inner diameter of the guiding part / outer diameter of the water rising
part
D4: diameter of the opening of the inner pot
E: angle between the central axis and the line connecting the two ends of the
guiding part
in the sectional plane passing the central axis of the steamer basket
H1: height of the bottom wall! maximum height difference between the water
rising part
and the water descending part
H2: height difference between the first through holes and the second through
holes
H3: height difference between the location of fitting and the top of the water
rising part
H4: height of the steamer basket
H5: height of the inner pot
M: lower border of the guiding part in the sectional plane passing the central
axis of the
steamer basket
N: upper border of the guiding part in the sectional plane passing the central
axis of the
steamer basket
S: location of fitting between the steamer basket and the inner pot
Detailed Description of the Invention
In the following description, numerous specific details are set forth in order
to provide a
more thorough understanding of the present invention. However, it will be
apparent to a
person skilled in the art that the embodiments of the present invention may be
practiced
without one or more of those details. In other examples, some technical
features known in
the art are not described in order to avoid confusion with the embodiments of
the present
invention.
For a thorough understanding of the embodiments of the present invention,
detailed
structures will be presented in the following description. Obviously, the
implementation of
the embodiments of the present invention is not limited to specific details
familiar to a
person skilled in the art. It should be noted that ordinal numbers such as
"first" and
"second" used in the present specification are merely references, and do not
have any
other meanings, such as a specific order. In addition, for example, the term
"first part"
does not imply by itself the presence of a "second part", nor does the term
"second part"
by itself imply the presence of a "first part", The terms "upper", "lower",
"front", "rear", "left"
and "right" and similar expressions used in the present invention are for the
purpose of
description and not limitation.
The present invention provides a cooking utensil and an inner pot assembly of
a cooking
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utensil. The cooking utensil according to the present invention can be an
electric rice
cooker, and can have functions such as porridge making, soup making, and food
steaming in addition to a rice cooking function.
A cooking utensil 100 and an inner pot assembly 30 according to a preferred
embodiment
of the present invention will be described in detail below in reference to
Figs. 1 to 4.
As shown in Fig. 1, the cooking utensil 100 mainly comprises a pot body 10 and
a lid body
20 provided above the pot body 10 and capable of opening and closing. The
inner pot
assembly 30 is provided in the pot body 10. When the lid body 20 covers the
pot body 10,
a cooking space is formed between the lid body 20 and the inner pot assembly
30. The
pot body 10 can be configured to have the shape of a cuboid with rounded
corners or any
other appropriate shape and has a receiving part in the shape of a cylinder.
The inner pot
assembly 30 is configured to be freely placed in the receiving part or removed
from the
receiving part to facilitate the cleaning of the inner pot assembly 30.
In addition, heating means 70, control means (not illustrated), and a
temperature sensing
assembly 80 are further provided in the pot body 10. The heating means 70 is
provided at
the bottom of the inner pot assembly 30, for example located below the inner
pot
assembly 30, so as to heat the food in the inner pot assembly 30. The control
means can
for example be a Micro Control Unit (or MCU for short) for controlling the
cooking process
of the cooking utensil. The temperature sensing assembly 80 is used for
detecting the
temperature of the inner pot assembly 30 and can be provided at the middle of
the bottom
of the inner pot assembly 30 or beside the inner pot assembly 30. A top
temperature
measuring element (not illustrated) can also be further provided on the lid
body 20 for
detecting the temperature in the cooking space. The heating means 70, the
temperature
sensing assembly 80, and the top temperature measuring element are all
electrically
connected to the control means. The temperature sensing parts send the
measured
temperature to the control means so that the control means can perform a more
precise
control of for example the heating means 700 based on temperature information.
It should be noted that in the present invention, directional terms "upper"
and "lower" refer
to those directions determined when the cooking utensil 100 is placed upright
and with the
lid body 20 in a closed state.
As shown in Figs. 1 to 4, the inner pot assembly 30 mainly comprises an inner
pot 40 and
a steamer basket 50 supported in the inner pot 40 and removable therefrom.
Preferably,
the steamer basket 50 is configured to be of a structure that is rotationally
symmetric
relative to its central axis A. Preferably, the central axis A of the steamer
basket 50
extends in a vertical direction. The steamer basket 50 comprises a bottom wall
51 and a
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side wall 52 extending upward from an outer border of the bottom wall 51. The
bottom wall
51 and the side wall 52 enclose an accommodating chamber for accommodating
rice.
Preferably, the side wall 52 is in the form of a cylinder. The maximum outer
diameter D2 of
the bottom wall 51 of the steamer basket 50 is smaller than the diameter D4 of
the
opening of the inner pot 40 so as to easily place the steamer basket 50 in the
inner pot 40.
It can be understood that the steamer basket 50 can also be configured as a
structure that
is not rotationally symmetric.
The bottom wall 51 comprises a water rising part 54, a guiding part 56, and a
water
descending part 53. The water rising part 54 is located in the middle, the
guiding part 56
extends outward from the outer border of the water rising part 54, and the
water
descending part 53 extends outward to the side wall 52 from the outer border
of the
guiding part 56. In other words, the bottom wall 51 of the steamer basket 50
sequentially
comprises, outwardly in the radial direction, the water rising part 54, the
guiding part 56,
and the water descending part 53. The water rising part 54 is higher than the
water
descending part 53. The water rising part 54 and the guiding part 56 enclose a
protrusion
protruding upward from the bottom wall 51, while the water descending part 53
comprises
the lowest part of the bottom wall 51 and is located on the outer periphery of
the protrusion.
Rice can be accommodated on the water rising part 54, the guiding part 56 and
the water
descending part 53. The water descending part 53 can be in contact with the
inner surface
of the inner pot 40 so as to form a sealed or quasi-sealed receiving space 60
between the
bottom wall 51 and the inner pot 40. The receiving space 60 is used for
receiving water.
During cooking, boiling water in the receiving space 60 can enter the steamer
basket 50
so as to soak and rinse the rice.
Preferably, the shape of the water rising part 54 matches that of the guiding
part 56 so that
the water rising part 54 transitions smoothly to the guiding part 56 at their
junction; the
shape of the water descending part 53 matches that of the guiding part 56 so
that the
water descending part 53 transitions smoothly to the guiding part 56 at their
junction.
Preferably, the bottom wall 51 and the side wall 52 are integrally formed (the
whole
steamer basket 50 is integrally formed), or the water rising part 54, the
guiding part 56 and
the water descending part 53 are integrally formed (the whole bottom wall 51
is integrally
formed). Preferably, the steamer basket 50 is made of metal, wood material or
plastic
material. The steamer basket has a wall thickness of 0.2 mm to 10 mm,
preferably 0.3 to 3
mm. Preferably, the bottom wall 51 is configured to be rotationally symmetric
relative to
the central axis A.
The water rising part 54 is provided with first through holes 57 communicating
with the
receiving space 60 and the water descending part 53 is provided with second
through
holes 58 communicating with the receiving space 60. As the water rising part
54 is higher
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than the water descending part 53, the first through holes 57 are higher than
the second
through holes 58. The guiding part 56 is a water-impermeable zone extending
from the
outer most border of the first through holes 57 to the inner most border of
the second
through holes 58. The guiding part 56 is relatively inclined from the outer
bottom to the
inner top. As shown in Fig. 12, the upper border of the guiding part 56, the
inner border of
the guiding part 56 and the outer border of the water rising part 54 are the
same border,
i.e., the outer most border of the first through holes 57 having an outer
diameter D3. The
lower border of the guiding part 56, the outer border of the guiding part 56,
and the inner
border of the water descending part 53 are the same border, i.e., the inner
most border of
the second through holes 58 having an inner diameter Dl. The inner diameter D1
of the
water descending part 53 is larger than the outer diameter D3 of the water
rising part 54.
Preferably, the first through holes 57 are provided at the highest location of
the water
rising part 54 (thus the highest location of the bottom wall 51), and the
second through
holes 58 are provided at the lowest location of the water descending part 53
(thus the
lowest location of the bottom wall 51). Preferably, the first through holes 57
and the
second through holes 58 are uniformly distributed. For example, the first
through holes 57
are provided at equal distance along the circumferential direction of the
water rising part
54, and the second through holes 58 are provided at equal distance along the
circumferential direction of the water descending part 53. Preferably, the
first through
holes 57 and the second through holes 58 are configured as circular through
holes. It can
be understood that the shapes of the first through holes 57 and the second
through holes
58 are not limited to the present embodiment. Based on needs, the first
through holes 57
and the second through holes 58 can also be configured to have the shape of an
oval, a
polygon, or any other appropriate shape. Preferably, the diameter of each
first through
hole 57 is smaller than or equal to 3 mm or the area of each first through
hole 57 is smaller
than or equal to 8 mm2, while the diameter of each second through hole 58 is
smaller than
or equal to 3 mm or the area of each second through hole 58 is smaller than or
equal to 8
mm2. With such dimensions, rice grains in the steamer basket 50 cannot fall
into the
receiving space 60 via the first through holes 57 and the second through holes
58.
A quasi-sealed receiving space 60 in which water is received is formed between
the
bottom wall 51 and the inner pot 40. As shown in Figs. 5 to 11, generally, the
water level
will not exceed the bottom wall 51 of the steamer basket, i.e., a vacant
guiding chamber
65 is left between the water surface and the bottom wall 51. The space below
the
protrusion enclosed by the water rising part 54 and the guiding part 56 forms
a main part
of the guiding chamber 65. During cooking, as the heating temperature rises,
air pressure
in the guiding chamber 65 gradually increases, and the water in the receiving
space 60
generates more and more water vapor and air bubbles, which further increase
the air
pressure in the guiding chamber 65. For safety and to prevent water from
splashing out,
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air pressure is generally below 4 kPa, for example, it can rise to
approximately 1.8 kPa. As
the guiding part 56 is relatively inclined from the outer bottom to the inner
top, when water
is heated to boil, boiling bubbles will emerge out of the water surface with
water under the
effect of pressure, and concentrate inside the bottom of the water rising part
54 under the
collecting effect of the guiding part 56. When the surface of the rice is
relatively flat, as the
water rising part 54 is higher than the water descending part 53, the
thickness of rice at
the water rising part 54 is lower than that at the water descending part 53,
which produces
a resistance difference, i.e. the resistance of rice at the first through
holes 57 is smaller
than that at the second through holes 58. Therefore, under the effect of
pressure, water
and air bubbles in the receiving space 60 rise into the steamer basket 50
until the upper
surface of rice through the first through holes 57 provided on the water
rising part 54. Thus,
water and gas enter the inside of the steamer basket 50 from the water rising
part 54
located relatively in the middle, then spread to the surrounding. Then, water
falls back into
the receiving space 60 via the surrounding second through holes 58, thereby
soaking and
rinsing rice inside the steamer basket 50. Therefore, starch and sugar
contents in the rice
inside the steamer basket 50 can fall back into the receiving space 60 via the
second
through holes 58 together with water, thus achieving the objective of reducing
sugar in the
rice. At the same time, the surface of rice located in the middle and that of
rice located at
the circumference can both be soaked by water, which can effectively prevent
rice from
being half-cooked.
In the present invention, under the collecting effect of the guiding part 56,
a large number
of air bubbles concentrate inside the bottom of the water rising part 54 where
a local
high-pressure zone is formed. At the same time, the resistance of rice at the
water rising
part 54 is relatively small. Thus, the first through holes 57 can achieve the
objective of
making water rise and water can rush to the upper surface of rice. It can be
understood
that in the present invention, it is possible that some water may fall back
into the receiving
space 60 via the first through holes 57 and that some water may enter the
steamer basket
50 via the second through holes 58.
Specifically, the water rising part 54 may comprise a plane face (as shown in
Fig. 2), an
upward protruding curved face, a downward depressing curved face, or a
combination of
a plane face and a curved face (as shown in Fig. 5 and Fig. 6). The water
descending part
53 may comprise a plane face (as shown in Fig. 2), an upward protruding curved
face, a
downward depressing curved face, or a combination of a plane face and a curved
face (as
shown in Fig. 7 and Fig. 8). The guiding part 56 may comprise any one of a
cylinder side
face, a truncated cone side face, or an arc-shaped face, or any combination
thereof (as
shown in Figs. 9 to 11). In the embodiment shown in Figs. 1 to 4, the bottom
wall 51 is
configured to be rotationally symmetric with the central axis A of the steamer
basket 50 as
its axis. The water rising part 54 is configured to be a circular plane and
the water
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descending part 53 is configured to be a ring-shaped plane. The top and bottom
of the
guiding part 56 are configured to be planes and respectively connected with
the water
rising part 54 and the water descending part 53. The top and bottom of the
guiding part 56
are connected with each other via a revolution face in the shape of a
truncated cone side
wall. In the embodiment shown in Figs. 13 and 14, the water rising part 54 is
configured to
be in the shape of a regular polygon, and the guiding part 56 is configured to
be
constituted of a plurality of inclined flat walls spliced together.
In order to make water rise and ensure that water can adequately soak the rice
inside the
steamer basket 50, the height of the water rising part 54 is a crucial factor
that controls the
amount of water that rises. When the maximum height difference H1 between the
water
rising part 54 and the water descending part 53 (i.e., the height of the
bottom wall 51) is
relatively small, the collecting effect of the guiding part 56 cannot be
adequately achieved,
and the difference of rice thickness on the bottom wall 51 is not significant
(i.e. rice
accumulating at the water rising part 54 is also relatively high), which makes
it difficult for
water entering the steamer basket 50 at the water rising part 54 to rush
through the upper
surface of rice. Therefore, the surface of the rice can hardly be soaked by
water, which
leads to half-cooked or relatively hard rice. On the other hand, when the
height H1 of the
water rising part 54 is too large, the first through holes 57 are too far away
from the water
surface in the receiving space 60, water brought up by air bubbles in the
guiding chamber
65 is relatively little, and air pressure in the guiding chamber 65 cannot
rise sufficiently. In
this case, the amount of water that rises via the first through holes 57 is
not sufficient,
which makes it difficult for the surface of rice to be soaked by water, easily
leading to a
half-cooked surface and a relatively poor sugar lowering effect.
The inventors of the present invention have obtained by experiments and tests
the impact
of the height difference H1 between the water rising part 54 and the water
descending part
53 on the cooking results. In the experiments, the nominal power of the
heating means 70
is 1200 W, the volume of the inner pot 40 is 4 L, the diameter D4 of the
opening of the
inner pot 40 is 201 mm, the volume of the steamer basket 50 is 2.6 L, the
maximum outer
diameter D2 of the bottom wall 51 of the steamer basket is 198 mm, the outer
diameter D1
of the guiding part 56 is 165 mm, the total area of all the first through
holes 57 is 117 mm2,
the total area of all the second through holes 58 is 197 mm2, the quantity of
rice
accommodated in the steamer basket 50 is 3 cups (approximately 450 g), and the
amount
of water accommodated in the receiving space 60 is 850 ml.
As shown in Table 1, when the height difference between the water rising part
54 and the
water descending part 53 H1 < 3 mm, the sugar content (reducing sugar) of rice
is
relatively high. Further, it is hard for water entering the steamer basket 50
to rush through
the rice surface since it encounters a relatively large resistance of rice at
the first through
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holes 57, which makes it difficult for the surface of rice to be soaked by
water and results
in a water content that is lower than industry standards. On the other hand,
when the
height different between the water rising part 54 and the water descending
part 53 H1 >
40 mm, although the sugar content (reducing sugar) satisfies industry
standards, the
water content is lower than industry standards because the height difference
H1 is so
large that the gravitational potential energy to be overcome by air bubbles
generated in
the receiving space in order to rise to the first through holes 57 increases,
which renders
the amount of rising water insufficient and makes it impossible for water
entering the
steamer basket 50 to soak the surface of rice. When the height difference H1
between the
water rising part 54 and the water descending part 53 is such that: 3 mm H1 40
mm,
the amount of water that rises via the first through holes 57 is sufficient
for water entering
the steamer basket 50 to relatively easily rush through the surface of rice
and thus fully
soak the rice, so as to ensure a consistency of the rice and therefore provide
a good sugar
lowering effect and better flavor of the rice. More preferably, H1 is such
that: 8 mm H1
30 mm, providing a better sugar lowering effect. More preferably, H1 is such
that: 10 mm 5
H1 20 mm, providing an optimal sugar lowering effect.
Table 1 Impact of Height Difference H1 between Water Rising Part 54 and Water
Descending Part 53 on Cooking Results
H1 Water Reducing Sugar Degree of Resistant Starch
(mm) Content (%) Content (mg/100 g) Gelatinization (%)
Content (%)
1 55.7 0.348 79.6 14.410
2 57.3 0.329 83.3 13.635
3 58.1 0.290 85.1 11.972
5 60.8 0.296 88.3 9.315
8 61.1 0.275 89.6 9.129
10 61.5 0.231 89.8 9.714
15 63.2 0.227 90.2 9.948
20 62.3 0.234 91.5 10.149
25 60.4 0.268 90.6 9.986
30 59.1 0.271 87.3 10.288
35 58.5 0.292 87.4 10.327
40 58.2 0.281 85.6 12.862
45 56.9 0.293 81.6 12.571
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It should be noted that, in industry standards, the water content is 58% to
65%, the
reducing sugar content is < 0.3 mg/100 g, the degree of gelatinization is 85%
to 95%, and
the resistant starch content is 8%. In addition, in a conventional cooking
mode in which
rice is fully immerged in water, the reducing sugar content of the rice
obtained is
approximately 0.529 mg/100 g, and the resistant starch content is
approximately 5.40%.
Therefore, the sugar lowering effect of the cooking utensil 100 according to
the present
invention is not only better than the conventional cooking mode but also
better than
industry standards.
In the present invention, the first through holes 57 mainly serve as holes for
water to rise
through, and the second through holes 58 mainly serve as holes for water to
descend
through. The height difference between the first through holes 57 and the
second through
holes 58 can essentially represent the height difference between the water
rising part 54
and the water descending part 53. In the present invention, any one of the
first through
holes 57 and any one of the second through holes 58 has a height difference
H2, and
preferably, H2 is such that: 3 mm H2 40 mm. More preferably, H2 is such that:
8 mm
H2 <30 mm. Still more preferably, H2 is such that: 10 mm < H2 <20 mm.
The first through holes 57 and the second through holes 58 have an appropriate
height
difference so that the thickness of rice placed above the first through holes
57 will be
smaller than that of rice placed above the second through holes 58 and thus
the
resistance (gravity) of rice at the first through holes 57 is smaller than
that at the second
through holes 58. The sum of the resistance of rice grains encountered by
water and air
bubbles in the receiving space 60 and their own gravitational potential energy
at the first
through holes 57 is smaller than the sum at the second through holes 58.
Therefore,
under the effect of pressure, water and air bubbles in the receiving space 60
are able to
rise to the accommodating chamber of the steamer basket 50 via the first
through holes
57 and rush through the upper surface of rice, then soak and rinse the rice in
the steamer
basket 50 in the accommodating chamber. Then, starch and sugar contents in the
rice in
the steamer basket 50 fall back into the receiving space 60 with water via the
second
through holes 58 and the first through holes 57, thus achieving the objective
of lowering
sugar in rice and preventing rice from being half-cooked.
The guiding part 56 is arranged to be inclined so as to collect water bubbles
at the inner
side of the bottom of the guiding part 56. Through the invention, it has been
discovered
that the angle E in the longitudinal sectional plane passing through the
central axis A of
the steamer basket 50 can also affect the amount of rising water and thus
affect cooking
results. As shown in Figs. 5 to 11, the angle E is the angle formed between
the line
connecting the two ends (M and N points) of the intersection line between the
guiding part
56 and the longitudinal sectional plane and the central axis A of the steamer
basket 50.
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The M point represents the inner most border of the second through holes 58 in
the
longitudinal sectional plane, and the N point represents the outer most border
of the first
through holes 57 in the longitudinal sectional plane. The M and N points
should be either
both located at borders of the first through holes 57 and the second through
holes 58
located at an upper surface of the bottom wall 51, or both at borders of the
first through
holes 57 and the second through holes 58 located at a lower surface of the
bottom wall 51.
In Figs. 5 to 11, the M and N points are both located at borders of the first
through holes
57 and the second through holes 58 located at the lower surface of the bottom
wall 51.
When the above-described angel E is too small, the area of the axial sectional
plane of the
guiding part 56 (i.e., the area of the axial sectional plane of the three-
dimensional shape
formed by the space enclosed by the water rising part 54, the guiding part 56
and the
water level, for example, the area of the axial sectional plane of the
truncated cone
enclosed by the water rising part 54 and the guiding part 56) and the space
inside the
guiding part 56 (i.e., the space enclosed by the water rising part 54, the
guiding part 56
and the water level, for example, the truncated cone enclosed by the water
rising part 54
and the guiding part 56) are relatively small, thus the volume of water and
air bubbles that
concentrate inside the bottom of the guiding part 56 is relatively small.
Therefore, the
amount of water that rises via the first through holes 57 is relatively small,
making it
difficult for rice to be thoroughly soaked, easily leading to half-cooked or
relatively hard
rice and a relatively poor sugar lowering effect. On the other hand, when the
above-described angle E is too large, the area of the axial sectional plane
and the space
inside the guiding part 56 are relatively large. Thus, a relatively large
amount of water and
air bubbles in the receiving space 60 needs to be concentrated (i.e., a
relatively large
pressure is required) for them to rise to the level of the first through holes
57. In addition,
under a given pressure, the speed of water in the receiving space 60 flowing
through the
first through holes 57 is reduced, which is not conducive to water rising.
Therefore, only a
relatively small amount of water can rise via the first through holes 57,
making it difficult for
rice to be thoroughly soaked, and easily leading to half-cooked or relatively
hard rice and
a relatively poor sugar lowering effect. The inventors of the present
invention have
discovered through experiments and tests that when the above-described angle E
is such
that 30" E 85", the amount of water that rises via the first through holes 57
can be
ensured so as to fully soak the rice and therefore ensure a good sugar lower
effect and
the flavor of the rice. More preferably, the above-described angle E is such
that: 55 E
80 .
It can be understood that the ratio F between the area of the guiding part 56
and the area
of the projection of the guiding part 56 on a horizontal plane can also
reflects the size of
the angle E. Preferably, F is such that: 1 < F 6.
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The ratio between the height difference H1 between the water rising part 54
and the water
descending part 53 and the angle E can also affect cooking results. VVhen the
ratio of the
height difference H1 to the angle E is relatively small, i.e., when the height
difference H1
between the water rising part 54 and the water descending part 53 is
relatively small or the
angle E is relatively large, it can be seen from the above description that
neither situation
is conductive to water rising, easily leading to half-cooked or hard rice.
VVhen the ratio of
the height difference H1 to the angle E is relatively large, i.e., the height
difference H1
between the water rising part 54 and the water descending part 53 is
relatively large or the
angle E is relatively small, it can be seen from the above description that
neither situation
is conducive to water rising, either. In fact, in this case, the amount of
water that rises via
the first through holes 47 is relatively small, making it difficult for rice
to be thoroughly
soaked, easily leading to half-cooked or hard rice and a poor sugar lowering
result. The
inventors of the present invention have discovered through experiments and
tests that
when the ratio of the height difference H1 between the water rising part 54
and the water
descending part 53 to the angle E is such that 0.035 mmr 5 H1/E 5 1.33 mmr, it
is
relatively easy for water and air bubbles in the receiving space 60 to rush
through the
surface of rice and the amount of water that rises through the first through
holes 57 can be
ensured, so that water entering the steamer basket 50 can fully soak the rice
and
therefore the sugar lowering result is relatively good and the flavor of the
rice is better.
Preferably, the ratio of the height difference H1 to the angle E is such that
0.12 mm/
H1/E 5 0.36 mm/ .
It can be understood that the angle E, which reflects the degree of
inclination of the
guiding part 56, and the height H1 of the bottom wall 51 affect the volume V
of the space
enclosed by the water rising part 54 and the guiding part 56. The larger the
angle E or the
height H1 is, the larger the volume V will be; the smaller the angle E or the
height H1 is,
the smaller the volume V will be. As described above, cooking results will be
affected if the
angle E and the height H1 are excessively large or small. In other words, the
angle E and
the height H1 have appropriate value ranges. Therefore, the volume V also has
an
appropriate value range. Preferably, the volume V is such that: 26000 mm3 5 V
5 800000
MM3.
It can be understood that the ratio of the maximum outer diameter D3 of the
water rising
part 54 to the minimum inner diameter D1 of the water descending part 53 can
also reflect
the size of the above-described angle E. Therefore, the ratio of D3 to D1
should have an
appropriate value range. Preferably, 0.02 5 D3/D1 5 0.5. More preferably, 0.1
5 D3/D1 5
0.25. D1 is preferably 100-240 mm. D3 is preferably 10-60 mm.
It can be understood that to ensure sufficient rising of water, the areas of
the water rising
part 54 and the guiding part 56 cannot be too small. Otherwise, the volume V
may be too
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small, or the height H1 may be too small, or the angle E may be too large.
Preferably, the
area of the water rising part 54 is equal to or larger than 80 mm2, and the
area of the
guiding part 56 is equal to or larger than 700 mm2.
It can be understood that the total area of the first through holes 57 and the
total area of
the second through holes 58 cannot be too small. Otherwise, the speed of water
rising or
descending will be reduced, which is not conducive to thoroughly soaking and
rinsing rice
with water. VVhen the total area of the first through holes 57 decreases, the
time for water
to rise will be prolonged and the corresponding cooking time will also be
prolonged. At the
same time, a decrease in the total area of the first through holes 57 means a
decrease in
the area of the water rising part 54, which increases the pressure in the
guiding chamber
65 and the rising water is squirted out, causing a risk when opening the lid.
A decrease in
the area of the second through holes 58 will hinder the descending of water
and result in
water accumulation in certain zones, which is not conducive to reducing the
sugar content
of rice. Generally, the total area of the first through holes 57 is equal to
or larger than 20
mm2, and the total area of the second through holes 58 is equal to or larger
than 50 mm2.
But the total areas of the first through holes 57 and of the second through
holes 58 cannot
be too large either. When the total area of the first through holes 57
increases, the
distribution range of the first through holes 57 becomes larger, so that the
rising water flow
is dispersed, which reduces the flow speed and pressure, and makes it
difficult to rush
through the water rising part 54. Further, an excessively large total area of
the second
through holes 58 will increase the amount of water that enters the steamer
basket 50 via
the second through holes 58, and thus reduces the amount of water rising
through the
water rising part 54, which will also affect the cooking results, especially
easily causing an
uneven flavor. In addition, when the total areas of the first through holes 57
and the
second through holes 58 are too large, the areas of the water rising part 54
and the water
descending part 53 will increase, which may affect the area and the angle of
inclination of
the guiding part 56. Preferably, the total area of the first through holes 57
ranges from 60
to 600mm2, and the total area of the second through holes 58 ranges from 100
to 600mm2.
More preferably, the total area of the first through holes 57 ranges from 60
to 400mm2,
and the total area of the second through holes 58 ranges from 100 to 400mm2.
It can be understood that in order to ensure the above-described area of the
water rising
part 54, area of the guiding part 56, total area of the first through holes
57, and total area
of the second through holes 58, the bottom wall 51 should have a sufficient
outer diameter.
Preferably, the area of the projection of the bottom wall 51 on a horizontal
plane is
11000-46000 mm2.
It can be understood that the larger the maximum outer diameter D2 of the
bottom wall 51
is, the more rice can be accommodated inside the steamer basket 50. In this
case, a
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larger amount of rising water is needed so as to fully soak and rinse the
rice. Therefore,
the dimensions of the water rising part 54 and the guiding part 56, which play
a leading
role in the water rising function of the bottom wall 51, should match the
dimensions of the
steamer basket 50. Preferably, the ratio of the area of projection of the
guiding part 56 on
a horizontal plane to the area of projection of the bottom wall 51 on a
horizontal plane
ranges from 0.25 to 0.9. Preferably, the ratio of the maximum outer diameter
D3 of the
water rising part 54 to the maximum outer diameter D2 of the bottom wall 51 is
such that:
0.05 < D3/D2 0.5.
Generally, the height H5 of the inner pot 40 is 90-200 mm, preferably 100 mm
to 155 mm.
The inventors of the present invention have discovered through experiments
that when
the volume of the receiving space 60 ranges from 200 ml to 2000 ml, the amount
of water
received in the receiving space 60 can meet the needs of the quantity of rice
in the
steamer basket 50. In order to ensure the volume of the receiving space 60,
the
dimensions of the steamer basket 50 should match those of the inner pot 40. In
particular,
the height H4 of the steamer basket 50 should match the height H5 of the inner
pot 50.
Preferably, 0.5 < H4/H5 0.9.
It can be understood that the larger the height H4 of the steamer basket is,
the larger the
quantity of rice that can be accommodated in the steamer basket 50 will be,
which may
increase the thickness of rice at the water rising part 54. As described
above, if the
thickness of rice at the water rising part 54 increases, resistance to water
rising will
increase and cooking results will be affected. On the other end, an increase
in the height
difference H1 between the water rising part 54 and the water descending part
53 (i.e. the
height of the bottom wall 51) can reduce the thickness of rice at the water
rising part 54.
As described above, the height H1 of the bottom wall 51 should be within an
appropriate
range. Therefore, the height H4 of the steamer basket 50 should be within an
appropriate
range as well so that the height H1 of the bottom wall 51 matches the height
H4 of the
steamer basket 50. Preferably, 0.05 H1/H4 0.4. More preferably, 0.08 H1/H4
0.3.
The steamer basket 50 is supported in the inner pot 40. In some embodiments
according
to the present invention, the steamer basket 50 contacts with the inner
surface of the inner
pot 40 with its bottom wall 51 so that the inner pot 40 can support the
steamer basket 50
while achieving the fitting of the steamer basket 50 to the inner pot 40 by
contact.
In an embodiment not illustrated, the steamer basket 50 can contact with the
inner surface
of the inner pot 40 with its side wall so that the inner pot 40 can support
the steamer
basket 50 while achieving the fitting of the steamer basket 50 to the inner
pot 40 by
contact.
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In another embodiment not illustrated, the steamer basket 50 can contact with
the inner
surface of the inner pot 40 with both its bottom wall 51 and its side wall so
that the inner
pot 40 can support the steamer basket 50 while achieving the fitting of the
steamer basket
50 to the inner pot 40 by contact
As shown in Figs. 1 to 3, the steamer basket 50 further comprises a supporting
part 59
extending circumferentially and provided at the outer most border of the water
descending
part 53. The supporting part 59 connects the bottom wall 51 and the side wall
52 of the
steamer basket 50 and is in the shape of an arc in the axial sectional plane
of the steamer
basket 50. The supporting part 59 is in contact with the inner surface of the
inner pot 40
along a circumferential direction and is supported on the inner surface of the
inner pot 40
so as to form a sealed or relatively sealed receiving space 60 between the
bottom wall 51
and the inner pot 40. Preferably, the location S of fitting between the
steamer basket 50
and the inner pot 40 (i.e., the location where the supporting part 59 contacts
with and
supported by the inner pot 40) is at the same level as or higher than the
lowest location of
the water descending part 53 of the bottom wall 51. Preferably, the location S
of fitting
between the steamer basket 50 and the inner pot 40 is at the same level as or
lower than
the highest location of the water rising part 54.
The location S of fitting being not higher than (at the same level as or lower
than) the
location of the highest point of the bottom wall 51 (i.e., the highest point
of the water rising
part 54) can effectively control the pressure relief at the location S of
fitting. As the sealing
between the supporting part 59 and the inner surface of the inner pot 40 is
sealing by
contact, not absolute sealing, gas can pass through the gap between the two.
In other
words, the location S of fitting also has a pressure relief capacity like the
first through
holes 57 and the second through holes 58. Water in the receiving space 60,
after being
heated to a certain temperature, can produce water bubbles, which will emerge
out of the
water surface. When the location S of fitting is relatively low, water bubbles
that emerge
out of the water surface will reach the location S of fitting. When the gap at
the location S
of fitting is very small, due to the tension of water, it will be difficult
for gas to pass through
the gap at the location S of fitting and thus the resistance encountered by
gas, water vapor,
and water bubbles at the location S of fitting is higher than the resistance
encountered at
the first through holes 57. Therefore, the water rising at the water rising
part 54 will not be
affected. When the location S of fitting becomes higher, it is more difficult
for water
bubbles to reach the height of the location S of fitting and easier for gas to
leak via the
location S of fitting. The higher the location S of fitting is, the higher the
pressure relief
capacity at the location S of fitting will be, and the larger the impact on
the water rising at
the water rising part 54 will be. On the other hand, when the location S of
fitting is at a
relatively large distance from the water surface in the receiving space 60,
the space for
receiving gas and air bubbles enclosed by the supporting part 59 and the inner
pot 40 is
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larger. Similar to guiding part 56, the supporting part 59 can also collect
gas and air
bubbles in the receiving space 60, so that gas in the guiding chamber 65 is
diverted. The
higher the location S of fitting is, the higher the flow diverting capacity at
the location S of
fitting will be, and the higher the pressure relief capacity at the location S
of fitting will be,
and thus the larger the impact on the water rising at the water rising part 54
will be.
Therefore, the location S of fitting should be arranged as low as possible and
the gap at
the location S of fitting should be as small as possible.
When the location S of fitting is not lower than (at the same level as or
higher than) the
location of the lowest point of the bottom wall 51 (i.e., the lowest point of
the water
descending part 53), the circumferential fitting between the outer surface of
the steamer
basket 50 and the inner pot 40 is facilitated so that the gap at the location
S of fitting is as
small as possible, while enabling a flexible choice among various structures
and shapes
for the water descending part 53.
The inventors of the present invention have discovered through experiments and
tests
that the location S of fitting is preferably not higher than the highest
location of the water
rising part 54 and not lower than the lowest location of the water descending
part 53. The
height difference in the vertical direction between the location S of fitting
and the top of the
water rising part 54 being H3, when the ratio between the height H1 of the
bottom wall 51
and the height difference H3 is such that 1 H1/H3 15, more water will rise via
the first
through holes 57, thereby improving the rice rinsing by water. Therefore. the
sugar
lowering effect and the rice's flavor are better.
In the embodiment shown in Figs. 1 to 3, as the inner pot 40 and the steamer
basket 50
are in contact with each other at the location S of fitting, with a very small
gap between the
two, a quasi-sealing structure is formed. Thus, the resistance for gas
escaping via the
location S of fitting is very large. Therefore, the resistance encountered by
water at the
first through holes 57 is smaller than the resistance encountered at the
second through
holes 58 and or at the location S of fitting of the supporting part 59. Thus,
water rising into
the steamer basket 50 via the first through holes 57 can rush through the
rice, to its
surface, and spread to the surrounding, achieving full soaking of rice. When
heating is
stopped, pressure inside the receiving space 60 drops, and liquid in the
steamer basket
50 can flow back into the receiving space 60 via the first through holes 57
and the second
through holes 58. By repeating this, the cooking process of rinsing rice is
achieved.
In the embodiment shown in Figs. 5 to 11, the contact between the steamer
basket 50 and
the inner pot 40 is the same as in the embodiment shown in Fig. 2. In such
embodiments,
the inner pot 40 supports the steamer basket 50 by an arc-shaped inner pot
side wall. It
can be understood that the inner pot 40 can also support the steamer basket 50
by an
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inclined bevel formed on the side wall of the inner pot. In other words, in
the axial sectional
plane of the inner pot 40, its side wall comprises an inclined straight line
instead of a
curved line, the straight line being inclined from the inner bottom to the
outer top of the
inner pot 40.
In the embodiment shown in Fig. 15, the support of the steamer basket 50 and
the fitting
between the inner pot 40 and the steamer basket 50 are still achieved by
circumferential
contact between the inner pot 40 and the bottom wall 51 of the steamer basket.
In this
embodiment, the inner pot 40 is provided with an inward protruding part 42
extending in
the circumferential direction and radially towards the inner side of the inner
pot 40. The
inward protruding part 42 is arranged to come into contact with the bottom
wall 51. The
contact location where the inward protruding part 42 contacts with the bottom
wall 51 is
the location S of fitting between the steamer basket 50 and the inner pot 40.
In other
words, the inner pot 40 supports the steamer basket 50 by contact with an
inward
protruding inner pot side wall. It can be understood that in this embodiment,
preferably,
the height difference H3 in the vertical direction between the location S of
fitting and the
top of the water rising part 54 and the height H1 of the bottom wall 51 are
such that 1
H1/H3 15.
In the embodiment shown in Fig. 16, the support of the steamer basket 50 and
the fitting
between the inner pot 40 and the steamer basket 50 are still achieved by
circumferential
contact between the inner pot 40 and the bottom wall 51 of the steamer basket.
In this
embodiment, the inner pot 40 is provided with a step part 43 extending in the
circumferential direction on its side wall and radially inward, so that the
inner diameter of
the lower part of the inner pot 40 is smaller than that of its upper part. The
step face 43A of
the step part 43 is a plane extending horizontally from the side wall of the
inner pot 40
towards the inside of the inner pot so that the bottom wall 51 of the steamer
basket can be
supported on the step face 43A. Specifically, the bottom wall 51 is supported
on the step
face 43A so as to be in contact with the inner pot 40, the location where the
bottom wall 51
contacts with the step face 43A is the location S of fitting between the
steamer basket and
the inner pot. In other words, the inner pot 40 supports the steamer basket 50
by its side
wall having an inward extending step. It can be understood that in this
embodiment,
preferably, the height difference H3 in the vertical direction between the
location S of
fitting and the top of the water rising part 54 and the height H1 of the
bottom wall 51 are
such that 1 H1/H3 15.
It can be understood that whether the supporting part 59 is configured to be
in an arc
shape, a straight shape, or a sharp angle, the inner pot 40 can always support
the
steamer basket 50 by contact by an arc-shaped side wall, an inclined side
wall, an inward
protruding side wall, or a side wall having an inward extending step.
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In the above described embodiment wherein the inner pot 40 supports the
steamer basket
50 by contacting with the bottom wall 51 of the steamer basket, the fitting
between the
inner pot 40 and the steamer basket 50 should be understood as follows: the
inner surface
of the inner pot 40 being provided with an inner pot fitting part and the
outer surface of the
bottom wall 51 of the steamer basket being provided with a steamer basket
fitting part, the
steamer basket fitting part coming in contact with the inner pot fitting part
when the
steamer basket 50 is placed in the inner pot 40 so that the steamer basket 50
is fitted to
the inner pot 40. The location where the steamer basket fitting part is in
contact with the
inner pot fitting part is the location S of fitting between the steamer basket
and the inner
pot, wherein, the height difference H3 in the vertical direction between the
location S of
fitting and the top of the water rising part 54 and the height H1 of the
bottom wall 51 are
such that 1 H1/H3 15.
In some other embodiments according to the present invention, the steamer
basket 50 is
provided with a connecting part by which the steamer basket is supported in
the inner pot
40, the steamer basket 50 being fitted to the inner pot 40 at a location other
than the
connecting part.
Specifically, the connecting part can be an upper edge 55 of the steamer
basket 50 by
which the steamer basket 50 is suspended on an opening flange 41 of the inner
pot. As
shown in Figs. 17 and 18, the steamer basket 50 comprises an upper edge 55
extending
outward from a top border of the side wall 52, the opening of the inner pot 40
is provided
with a flange 41, and the upper edge 55 is supported on the flange 41. In
other words, the
steamer basket 50 is suspended in the inner pot 40. In such embodiments, the
bottom
wall 51 of the steamer basket is not in contact with the inner pot. It can be
understood that
in such mode of supporting, there is a gap between the side wall 52 of the
steamer basket
and the side wall of the inner pot. When water in the receiving space 60
starts to boil, the
gap can divert water vapor, gas and air bubbles produced by boiling water. To
reduce the
impact of the gap on the water rising at the water rising part 54, such
embodiments
respectively adopt the following measures to ensure the water rising at the
water rising
part 54.
In the embodiment shown in Fig. 17, the outer surface of the steamer basket 50
(for
example, the outer surface of its side wall 52) is provided with a sealing
element 52A
extending circumferentially. For example, the outer surface of the side wall
52 can be
provided with a circumferential groove. Then the sealing element 52A made of
an elastic
material (for example, rubber or silica gel) is bonded to or directly sleeved
in the groove
such that the sealing element 52A protrudes from the outer surface of the side
wall 52.
When the steamer basket 50 is placed in the inner pot 40, the sealing element
52A can be
in contact with the inner surface of the inner pot 40 so as to block the gap
between the
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side wall of the steamer basket and the side wall of the inner pot. In this
embodiment, the
inner pot 40 and the steamer basket 50 are fitted by means of the sealing
element 52A.
The steamer basket fitting part is materialized by the sealing element 52A and
the inner
pot fitting part is provided at the location of the inner surface of the inner
pot 40
corresponding to the sealing element 52A. The location of contact between the
inner pot
fitting part and the steamer basket fitting part is the location of fitting.
Preferably, the
location S of the sealed fitting is not higher than the top of the water
rising part 54.
In the embodiment shown in Fig. 18, the inner surface of the inner pot 40 is
provided with
an inward protruding rib 44 extending circumferentially and approaching the
outer surface
of the steamer basket 50 (for example, the outer surface of its side wall 52).
In such
embodiment, the fitting between the inner pot 40 and the steamer basket 50 can
be
understood as fitting by proximity. The inner pot fitting part of the inner
pot 40 is
materialized by the inward protruding rib 44 and the steamer basket fitting
part is the part
of the outer surface of the side wall 52 corresponding to the inward
protruding rib. It can
be understood that in this embodiment, when the steamer basket 50 is placed in
the inner
pot 40, there may exist a gap between the inner pot fitting part and the
steamer basket
fitting part. Preferably, at the location S of fitting, the distance between
the inner pot 40
and the steamer basket 50 does not exceed 1 mm.
It can be understood that the outer surface of the steamer basket 50 can also
be provided
with an outward protruding rib extending circumferentially and approaching the
inner
surface of the inner pot 40. In such embodiment of fitting by proximity, the
steamer basket
fitting part is materialized by the outward protruding rib at its outer
surface, and the inner
pot fitting part is the part of the inner surface of the inner pot 40
corresponding to the
outward protruding rib. Preferably, at the location S of fitting, the distance
between the
inner pot 40 and the steamer basket 50 does not exceed 1 mm.
Preferably, in an embodiment of fitting by proximity, the location S of
fitting is not higher
than the top of the water rising part 54. Preferably, the height difference H3
between the
location S of fitting and the top of the water rising part 54 and the height
H1 of the bottom
wall 51 are such that: 1 H1/H3 15.
In an embodiment not illustrated, the bottom part of the steamer basket 50 is
provided with
a plurality of supporting feet extending downward or a supporting cylinder for
coming into
contact with the bottom wall of the inner pot 40. The supporting feet or the
supporting
cylinder are the connecting part of the steamer basket. The steamer basket 50
and the
inner pot 40 are fitted at a location other than the supporting feet or
supporting cylinder, for
example, fitted by means of a sealing element or a protruding rib.
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In the embodiments shown in Figs. 17 and 18, the receiving space 60 is
delimited by the
bottom wall 51 of the steamer basket, the side wall 52 of the steamer basket,
and the
inner pot 40.
In the embodiments shown in Figs. 2, 5-11, and 15-16, the inner pot 40 and the
steamer
basket 50 are fitted by contact. But it can be understood that, due to the
imperfections of
the processing methods, it cannot be guaranteed that the inner pot 40 and the
steamer
basket 50 remain in contact all along the circumference. In other words, in
these
embodiments, a gap may exist between the inner pot fitting part and the
steamer basket
fitting part. Preferably, when the steamer basket 50 is placed in the inner
pot 40, the
1(:) distance between the inner pot fitting part and the steamer basket
fitting part does not
exceed 1 mm (smaller than or equal to 1 mm). Thus, even if there exists a gap
between
the inner pot fitting part and the steamer basket fitting part, as the gap is
very small, a
quasi-sealed chamber can be formed between the side wall 51 of the steamer
basket
and the inner pot 40, or between the bottom wall 51 of the steamer basket, the
side wall
52 of the steamer basket, and the inner pot 40. The above range of the gap
size can
ensure that the resistance to boiling water in the receiving space 60 at the
gap is larger
than that at the first through holes 57 and that at the second through holes
58 so that it is
difficult for boiling water in the receiving space 60 to pass through the gap,
thus ensuring
the water rising at the water rising part 54.
In sum, when the steamer basket 50 is placed in the inner pot 40, the steamer
basket
fitting part and the inner port fitting part are in contact with each other or
close to each
other, the distance between the steamer basket 50 and the inner pot at the
location of
fitting being smaller than or equal to 1 mm.
As shown in Fig. 2, the steamer basket 50 further comprises a holding part 61
configured
to extend circumferentially from the top of the side wall 52 and to be
depressed toward the
central axis A of the steamer basket 50 relative to the side wall 52, so that
the steamer
basket 50 can be easily held and moved by a user.
In addition, the side wall 52 of the steamer basket is provided with a
plurality of side wall
through holes 62. Excessive water and foams in the steamer basket 50 can be
discharged
to the inner pot 40 via the side wall through holes 62, reducing the
possibility of
overflowing. The side wall through holes 62 are provided at the upper part of
the side wall
52. Specifically, the side wall through holes 62 are higher than the steamer
basket fitting
part. In other words, the side wall through holes 62 are provided above the
location of
fitting so that it is difficult for gas and air bubbles generated by boiling
water in the
receiving space 60 to enter the steamer basket 50 via the side wall through
holes 62. This
disposition can also limit the pressure relief capacity of the location of
fitting and thus
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ensuring the water rising at the water rising part 54. Preferably, the side
wall through holes
62 are provided in a spaced manner along the circumference of the side wall 52
so that
excessive water and foams in the steamer basket 50 can be discharged into the
inner pot
40 via the side wall through holes 62, thus reducing the possibility of
overflowing
The inner surface of the inner pot 40 is provided with at least one water
level line (not
illustrated), different water level lines corresponding to different
quantities of rice. When
the steamer basket 50 is placed in the inner pot 40, at least one water level
line is lower
than the second through holes 58, for example, at 0-10 mm below the second
through
holes. When the water level is lower than the second through holes 58, rice is
separated
from water and will only come into contact with water during cooking and when
water is
boiling thus enters the accommodating chamber via the first through holes 57.
Thus, all
the rice can be rinsed and soaked at the same time, which helps maintain the
consistency
of the flavor of rice. In addition, with the water level being below the
second through holes
58, a relatively small amount of water is enough for cooking, which helps save
water while
enabling water in the receiving space 60 to be heated to boil more quickly. In
other words,
this enables a quicker execution of the rinsing step, which will be described
in detail below.
At the same time, for a cooking utensil with a reservation function, water in
the receiving
space 60 will not come into direct contact with rice in the accommodating
chamber of the
steamer basket 50 during the waiting period, thereby avoiding foul odors.
Especially in
summertime, if rice is soaked in water for a long time, foul odors are more
significant, and
rice may even become spoiled and therefore inedible. By providing an water
level line
below the second through holes 58, foul odors and spoiling can be avoided and
the
duration of reservation can be prolonged. It can be understood that, based on
needs, for
different quantities of rice or different dimensions of the inner pot and of
the steamer
basket, when the steamer basket 50 is placed in the inner pot 40, a water
level line at the
inner surface of the inner pot 40 can also be lower than the first through
holes 57 but
higher than or at the same level as the second through holes 58.
Further, the inner surface of the steamer basket 50 is provided with at least
one steamer
basket water level line (not illustrated). Different volumes of water can be
added based on
needs while ensuring that the amount of water is as small as possible so that
water in the
receiving space 60 can be heated to boil more quickly, i.e., the rinsing step
(which will be
described in detail below) can be executed more quickly.
The plurality of water level lines on the inner pot 40 and the steamer basket
50 provides
indications of the amounts of water corresponding to different quantities of
rice for a user's
reference.
The rice cooking process of the cooking utensil 100 is described below.
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First, an appropriate amount of water is added to the inner pot 40 according
to the water
level line. If there are a plurality of water level lines in the inner pot 40,
then an amount of
water corresponding to the quantity of rice to be cooked is added. Next, rice
is placed in
the steamer basket, and the steamer basket, with the rice accommodated in it,
is placed in
the inner pot. Then, a corresponding rice cooking program is selected for
cooking.
In a preferred embodiment, the rice cooking process of the cooking utensil 100
sequentially comprises the following steps.
1. Reservation process
The reservation process means that a user places food in the cooking utensil
in advance
and then sets a reservation duration and a cooking mode (such as rice cooking
or
porridge making) so that the cooking utensil can complete the cooking based on
the
requirements of the cooking mode at the moment when the reservation duration
has
elapsed from the current moment. As described above, when the water level is
lower than
the second through holes 58, it can be ensured that rice and water are
separated and a
longer reservation duration can be set. When reservation is not needed, this
step can be
skipped and the cooking utensil proceeds directly to the preheating process.
2. Preheating process
In the preheating process, the control means controls the heating means 70 to
heat the
inner pot assembly 30. Preferably, the heating power is 1200 W. When a top
temperature
measuring element detects that the temperature has reached a preset
temperature T, the
cooking utensil proceeds to the rice rinsing and cooking process. In the
present
embodiment, the preset temperature T is such that 65 C T 90 C. Preferably, the
present temperature T is such that 65 C < T 80 C.
3. Rice rinsing and cooking process
The rice rinsing and cooking process is an important step that allows to
achieve the sugar
lowering effect of the cooking utensil according to the present invention.
The control means controls the heating means 70 to intermittently heat the
inner pot
assembly 30 so that boiling water in the receiving space 60 rises and enters
the
accommodating chamber via the first through holes 57. Water having entered the
accommodating chamber, after soaking and rinsing water, falls back into the
receiving
space 60 via the first through holes 57 and the second through holes 58. In
the rice rinsing
and cooking process, rice is rinsed multiple times, for example N times (N
being a natural
number). During each rinsing, the heating means 70 performs heating for a
first preset
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duration and then stops heating for a second preset duration.
The nominal power P of the inner pot assembly 30 can adjust the pressure in
the receiving
space 60 and how many air bubbles are generated, thereby affecting the amount
of water
rising via the first through holes 57 and further affecting the cooking
results. When the
nominal power P of the inner pot assembly 30 is too small, for example when
the nominal
power P < 600 W, gas and air bubbles produced in the receiving space 60 are
not
sufficient, and the pressure in the receiving space 60 is relatively low,
which is therefore
not conducive to water rising. Thus, the amount of water rising via the first
through holes
57 is relatively little so that rice can hardly be soaked by water thoroughly,
easily resulting
1(:) in half-cooked or hard rice. VVhen the nominal power P of the inner
pot assembly 30 is too
large, the heating means is costly itself and having a high electricity
consumption, which
increases the cost of use for a user. When the nominal power P of the inner
pot assembly
30 is such that 600 W P 1500 W, the amount of water rising via the first
through holes
57 can be ensured so that water can fully soak the rice, thus ensuring the
sugar lowering
effect and the flavor of the rice. At the same time, the costs of the heating
means are
relatively low, in addition to the relatively low electricity consumption,
which can reduce
the costs of use and improves the user's utilization experience.
In the rice rinsing and cooking process, preferably, the heating power is 600-
1500 W.
More preferably, the heating power is 1200 W. During each rinsing, boiling
water can rise
and enter the accommodating chamber via the first through holes 57 during
heating, and
water having entered the accommodating chamber soaks and rinses water. When
the
heating is stopped, water in the accommodating chamber falls back into the
receiving
space.
When the number of times of rinsing reaches N (N times of heating), or the
duration of the
rice rinsing and cooking process reaches a preset rinsing duration, the
cooking utensil
proceeds to the rice steaming process.
Optionally, the heating means 70 is an electromagnetic heating element, the
number of
times of rinsing N is 8 to 12, the first preset duration is 5-25 s, the second
preset duration
is 10-35 s, and the preset rinsing duration is 10-30 minutes.
Optionally, the heating means 70 is a heating plate, the number of times of
rinsing N is 18
to 30, the first preset duration is 7-28 s, the second preset duration is 8-25
s, and the
preset rinsing duration is 5-15 minutes.
4. Rice steaming process
In the rice steaming process, the control means controls the heating means 70
to heat the
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inner pot assembly 30 so that water in the receiving space 60 boils and rice
is cooked by
steaming with water vapor. Preferably, in the rice steaming process, the
heating power is
700 W. When the duration of the rice steaming process reaches a preset rice
steaming
duration (for example, 6-10 minutes), the cooking utensil proceeds to the rice
braising
process.
5. Rice braising process
After completing the rice steaming process, the cooking utensil proceeds to
the rice
braising process. The rice braising process is a later stage in the cooking
process, during
which, a relatively high temperature is still maintained in the inner pot 40
and the steamer
basket 50 after the rice steaming process, so as to ensure that food is fully
cooked by
steaming. When the duration of the rice braising process reaches a preset rice
braising
duration (for example, 8-15 minutes), the cooking utensil proceeds to the heat
preservation process. Preferably, in the rice braising process, the heating
power is 500 W.
The heating power of the preheating process is higher than that of the rice
steaming
process and that of the rice braising process. The heating power of the rice
rinsing and
cooking process is higher than that of the rice steaming process and that of
the rice
braising process. The heating power of the rice steaming process is higher
than that of the
rice braising process.
6. Heat preservation process
When the rice braising process is completed, the substantive cooking work is
completed.
But sometimes a user does not eat right away, the cooking program further
provides a
heat preservation process to maintain the temperature of cooked food so that
when warm
food can be served whenever the user needs. The temperature during the heat
preservation process is controlled to be within a lower limit temperature and
an upper limit
temperature. When the temperature sensing assembly 80 detects that the
temperature of
the inner pot assembly 30 is lower than the lower limit, the control means
controls the
heating means 70 to operate. When the temperature sensing assembly 80 detects
that
the temperature of the inner pot assembly 30 is higher than the upper limit,
the control
means controls the heating means 70 to stop operating. Generally, the
temperature of the
heat preservation process is controlled to be 70-80 C.
Unless otherwise defined, technical and scientific terms used herein have the
same
meanings as commonly understood by a person skilled in the art of the present
invention.
The terminology used herein is for the purpose of describing particular
implementations
only and is not intended to limit the present invention. Terms such as
"provided" may
mean that one part is directly attached to another part or that one part is
attached to
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another part through an intermediary part. A feature described herein in one
embodiment
may be applied to another embodiment alone or in combination with another
feature,
unless the feature is not applicable in the other embodiment or stated
otherwise.
The present invention has been described by means of the above-described
embodiments, but it should be understood that the above-described embodiments
are
only for the purpose of illustration and description, and are not intended to
limit the present
invention to the scope of the described embodiments. It will be appreciated by
a person
skilled in the art that various variations and modifications can be made
according to the
teachings of the present invention, and those variations and modifications all
fall within the
scope of protection claimed by the present invention.
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