JP5072803B2 - rice cooker - Google Patents

Description

The present invention relates to an electromagnetic induction heating type cooker for use in general household.

  Conventionally, there has been a rice cooker in which an air layer is provided in the inner pot housing portion opposed to the outer peripheral portion of the inner pot to reduce power consumption during heat insulation, and a resin molded portion having a low thermal conductivity is formed on the outer peripheral portion of the inner pot. Yes (see, for example, Patent Document 1).

Japanese Patent Laid-Open No. 2002-440 (pages 1 to 3 and FIG. 1)

In the conventional rice cooker shown by patent document 1, the heat insulating material (resin shaping | molding part) becomes obstructive at the time of rice cooking (at the time of heating), and the heating rate becomes slow and the rice cooking time becomes long, and the heat capacity which a heat insulating material has increases. There is a problem that energy consumption during cooking increases.
The problem to be solved was an increase in the heat capacity of the heat insulating material. Also, in order to obtain a sufficient cutting effect even when the outside air becomes cold, such as in winter, it is necessary to increase the thickness of the heat insulating material, which increases the heat capacity of the heat insulating material, which further increases the energy consumption during rice cooking There was a problem to do.
This invention was made in order to solve the problems as described above, and a first object thereof is a rice cooker and a rice cooker in which there is no decrease in the heating rate during rice cooking, and energy consumption during rice cooking does not increase. It is to provide a control method. Moreover, the 2nd objective is to provide the rice cooker which can perform the stable rice cooking also in the low temperature outside air environment of winter.

A rice cooker according to the present invention covers a rice cooker body having a main heating portion at the bottom, an inner pot detachably accommodated in the rice cooker body, and an outer periphery of the inner pot with a predetermined gap therebetween, in a radial direction. releasing a deformable cylindrical inner hook accommodating portion, and the auxiliary heating means attached to the side surface of the inner hook accommodating portion, the adhesion or close contact with the inner kettle inner hook accommodating portion in synchronization with the heating operation of the auxiliary heating means A movable means for controlling the main heating unit to perform a rice cooking process including a preheating process, a boiling process , and a steaming process , and a control means for controlling the heating operation of the auxiliary heating means under a predetermined condition. And the control means does not operate the auxiliary heating means so that the movable means does not contact the inner pot storage part with the inner pot in the preheating process, and the movable means uses the inner pot storage part as the inner pot in the boiling process and the steaming process. Auxiliary heating means so that the amount of heating is close enough Heat to perform the in final stage of steaming step, to be a heating amount enough to release the adhesion between the inner hook accommodating portion and the inner hook is movable means, also of a is Ru to perform the heating in the auxiliary heating means.

In the rice cooker of the present invention, the side surface of the inner pot and the inner pot storage part is separated from the start of rice cooking during the preheating step, and there is a gap, so the main heating energy is transmitted to the inner pot and the object to be heated, and the air in the gap Since the heat transfer is low, it has the effect of reducing the heat escaping to the outside by being stolen by the inner pot storage.
In addition, in the boiling process, the inner pot storage portion provided with the auxiliary heating means is brought into close contact with the inner pot, so that the heat of the auxiliary heating means can be directly transferred to the inner pot in addition to the heat of the main heating portion, so that the heat transfer efficiency is improved Since the temperature increases and the inner pot can be heated in a short time, the reaction of heating is improved, the accuracy of temperature adjustment is improved, and furthermore, the input power to the heater can be reduced and energy can be saved.

Embodiment 1 FIG.
1 is a longitudinal sectional view of an electromagnetic induction heating rice cooker according to Embodiment 1 of the present invention.
As shown in FIG. 1, the rice cooker includes an outer frame 1 that is an outer shell of the rice cooker, an inner pot storage portion 2 that is integrally formed with the outer frame 1 and constitutes the rice cooker body together with the bottom surface 3, and the inner pot storage. It is comprised from the inner hook 20 accommodated in the part 2 so that attachment or detachment is possible. In addition, there is a gap (air layer 2 a) between the inner hook storage portion 2 and the inner hook 20. The tubular actuator 60 (which constitutes the movable means) arranged along the outer peripheral surface of the inner pot accommodating portion 2 is an alloy containing Ti and Ni that changes its shape depending on the presence or absence of thermal load or current load, or Ti and Ni And alloy containing Co. There are a fixing member 61 for fixing the tubular actuator 60 on the outer peripheral surface of the inner pot accommodating portion 2, and a body heater 62 (constituting auxiliary heating means) disposed in the tube of the tubular actuator 60.

  The temperature detection device 4 (which constitutes temperature detection means) is attached to the center of the bottom surface 3 and is pressed by the bottom surface of the inner hook 20. The induction heating coil 5 is attached to the bottom surface 3 of the inner pot housing 2. Further, the ferrite 6 is attached to the lower portion of the induction heating coil 5 and is fixed integrally with a coil cover 7. The bottom 8 forms a bottom portion and has an intake hole 9 and an exhaust hole 10 for the cooling fan 11.

  A control collar 12 (which constitutes a control means) is attached to the coil cover 7 via a collar cover 13 below the inside of the main body. Further, the lid 15 is attached with a heat radiating plate 17 with a lid heater 16 attached thereto via a spring 18, and pivots on a hinge 1 a provided on the outer frame 1 to close the upper end of the inner hook 20. The button 19 is configured to be locked.

  FIG. 2 a is a perspective view showing a configuration around the inner hook storage portion 2 including the inner hook 20 of the first embodiment. FIG. 2b is a partial cut view in which a part of FIG. 2a is cut. In FIG. 2a, the inner hook storage portion 2 is formed in a cylindrical shape so as to surround the inner hook 20 having a cylindrical side surface, but the inner hook storage portion 2 is not an endless cylinder but has at least one mating portion 65. The mating portion 65 is provided with a gap 65a that varies in distance.

FIGS. 3 a and 3 b are a plan view and a longitudinal sectional view for explaining the operation of the inner hook 20, the inner hook housing portion 2, and the tubular actuator 60.
FIG. 4 is a diagram illustrating the rice cooking process of the first embodiment of the present invention, and shows the relationship between the rice cooking process, the ON-OFF control operation of the body heater 62, and the change in the diameter of the storage unit 2.

  Next, the operation will be described with reference to FIGS. When a user puts an appropriate amount of rice and water into the inner pot 20 and puts a rice cooking switch (not shown), power is supplied to the induction heating coil 5 by the operation of the control kiban 12, and the inner pot 20 generates heat by induction heating. Cooking rice starts. At this time, the high-frequency magnetic field generated by the induction heating coil 5 acts only on the inner pot 20 which is a magnetic metal material and is converted into heat.

  During rice cooking, induction heating is controlled by an instruction from the control hub 12 based on the temperature information of the temperature detection device 4. Rice cooking is roughly divided into four steps as shown in FIG. 4, and the preheating step (controls the induction heating coil 5 so as to reach the temperature T1) and the boiling step (temperature T2 = approximately 100 ° C.). Control) and after dry-up (temperature T3), the process proceeds to the unevenness process. During cooking (especially during boiling), the inner pot 20 becomes hot and heat is transmitted to the inner pot accommodating portion 2 to heat the air in the air layer 2a.

  When cooking rice, the control kiban 12 also becomes high temperature, but the cooling fan 11 takes in the outside air from the intake hole 9 provided in the bottom 8 and cools it and discharges it from the exhaust hole 10 to keep the temperature low.

  In the rice cooking process shown in FIG. 4, the body heater 62 is turned off in the preheating process, the body heater 62 is intermittently turned on and off at the cycle t1 in the boiling process, and the body heater 62 is turned on and off in the cycle t2 in the unevenness process. OFF is intermittently performed, and the ON-OFF time of the body heater 62 is controlled so as to maintain the temperature T5 in the temperature maintaining process.

Since the tubular actuator 60 is a Ni-Ti alloy or Ni-Ti-Co alloy having a shape memory action, the temperature rises due to the heat transmitted from the body heater 62 and the inner pot 2, and the temperature Tx becomes a boundary. The shape changes like b.
FIG. 3A shows the shape of the tubular actuator 60 when the temperature is less than Tx, and the inner hook housing portion 2 connected to the tubular actuator 60 with a diameter DL is not in contact with the inner hook 20 and has a gap in the air layer 2a. . Further, the gap 65a of the mating portion 65 is larger than a predetermined value.
FIG. 3B shows the shape of the tubular actuator 60 when the temperature ≧ Tx. The inner hook housing portion 2 connected to the tubular actuator 60 with a diameter of Ds comes into contact with the inner hook 20, and the air layer 2a disappears. At this time, the gap 65a of the mating portion 65 is smaller than in the case of FIG.
That is, from the start of rice cooking until the temperature of the heated object such as rice inside the inner pot 20 reaches T1 ° C., the inner pot storage portion 2 has a large diameter DL, and there is a gap between the inner pot 20 and the side wall. Maintain the provided state. When T1 ° C. is reached, heating by the body heater 62 (heater ON-OFF) is started at the same time, and the outer wall of the inner pot 20 is brought into close contact with the inner pot storage portion 2 having a diameter Ds. At the stage of lowering the rice temperature at the end of the unevenness process, the diameter is returned to DL to release the close contact, thereby providing a gap, and the ON-OFF cycle of the body heater 62 is lengthened.

  In the preheating process, the temperature of the tubular actuator 60 is <Tx, and there is an air layer 2a between the inner hook housing portion 2 and the inner hook 20, so that the preheating temperature T1 ° C. is maintained by the heat insulating effect of the air layer 2a. Heating energy can be reduced.

  In the boiling process and the unevenness process, the tubular actuator 60 and the inner pot accommodating portion 2 are heated by the heat transmitted from the body heater 62 and the inner pot 2, so that the temperature of the tubular actuator 60 is equal to or greater than Tx, and the diameter of the inner pot accommodating portion 2 is Ds. The outer wall of the inner pot 20 is closely attached. That is, the heating energy of the trunk heater 62 is directly transmitted to the inner hook 20, and heat of the trunk heater 62 can be efficiently transmitted to the inner pot 20 without any heat transfer loss.

In this way, when the rice cooking progresses and the water in the inner pot 20 is exhausted, the rice cooking is completed and the process proceeds to the heat retaining process automatically or by the user's selection. In the heat retaining step, when the temperature of the cooked rice is lowered to the heat retaining temperature (T4 = approximately 60 ° C. to 74 ° C.), the temperature detecting device 4 works to energize the lid heater 16, the body heater 62 and the induction heating coil 5 to heat the inner pot 20. When the temperature of the inner pot 20 rises due to the heating and the temperature of the temperature detecting device 4 rises, the heating is stopped, and thereafter the heat retention temperature is maintained by repeating this.
When the outside air temperature is high, such as in summer, the number of times the body heater 62 is turned on is small, the temperature of the tubular actuator 60 is <Tx, and there is an air layer 2a between the inner hook storage portion 2 and the inner hook 20, so Since the heat insulation temperature can be maintained by the heat insulation effect by 2a, energy-saving heat insulation can be performed.
When the outside air temperature is extremely low such as in winter, the heat from the outer frame 1 that is the outer shell of the rice cooker is large, so the body heater 62 is frequently turned on. At this time, the temperature of the tubular actuator 60 becomes ≧ Tx, and the inner pot The diameter of the storage part 2 becomes Ds, and the heat energy can be transmitted efficiently by closely contacting the outer wall of the inner pot 20, and it is possible to keep the heat at an energy-saving and stable temperature even in winter.

In the heat retaining step, a phenomenon occurs in which a portion having a temperature lower than the cooked rice temperature condenses in the substantially sealed space between the radiator plate 17 and the inner pot 20, but an air layer 2 a is provided between the inner pot storage portion 2 and the inner pot 20. As a result, the heat insulation effect is high and heat radiation can be minimized, so that dew condensation on the side surface of the inner pot 20 can be prevented, and contact between the inner heater 62 and the inner pot 20 according to the outside air environment in summer and winter, non-contact Condensation can be prevented without being influenced by the outdoor air environment in the summer and winter on the side by the auxiliary heating by the control.
Further, in addition to the body heater 62 that efficiently transfers heat without contact, the heat sink 17 is brought into contact with the upper portion of the inner hook 20 to efficiently transfer the heat of the lid heater 16, and the induction heating coil is provided at the bottom portion of the inner pot 20. 5, the inner hook 20 itself generates heat, and condensation can be prevented.
By the rice cooker of the said embodiment, it can heat efficiently, can maintain a cooked rice state favorably without the influence of the outside air environment of summer and winter, and can anticipate the effect of a high energy saving.

In the above example, the diameter of the cylinder of the inner hook housing portion is changed by the shape memory alloy. However, the present invention is not limited to this, and an X-shaped X link 70 as shown in FIG. The wall-side support portions 71, which are one end of the link 70, are engaged with each of the cylindrical end portions of the inner hook housing portion 2, and the other ends are attached to a shaft 73 and a solenoid 74 to which a spring 72 is attached. The shaft 73 may be configured to be driven in the left-right direction by the solenoid 74, and the diameter of the cylinder may be mechanically changed. In this case, when the shaft 73 is driven by the solenoid 74, both solenoid-side tips of the X link 70 reciprocate in the left-right direction. As a result, the wall-side support portions 71 at the other ends of the X link 70 also reciprocate in the left-right direction around the fulcrum 75, forcibly pulling the mating portion of the inner hook storage portion 2 or returning it in the opposite direction. Or In this manner, the diameter of the cylinder of the inner hook storage portion 2 can be mechanically changed.
It is also possible to configure the bobbin housing portion 2 in a high heat transfer conductivity constant material such as metal. Accordingly, since it is uniformly heat conductive throughout the bobbin accommodating portion 2 heat which is heated by the barrel heater 62, it is possible to uniformly heat the entire side of the inner hook, becomes possible without unevenness cooking. Moreover, since the trunk heater can be arranged outside the cylinder of the inner pot storage portion 2, it is advantageous in terms of storage space and gap formation compared to the case where it is arranged inside.

  Examples of utilization of the present invention include mahobins and electric water heaters.

It is sectional drawing from the right view which shows Embodiment 1 of this invention. It is a perspective view which shows the structure of the inner hook and inner hook accommodating part which show Embodiment 1 of this invention. It is the top view and sectional drawing which show the structure of the inner hook and inner hook accommodating part which show Embodiment 1 of this invention. It is process drawing which shows operation | movement of the rice cooking process and trunk | drum heater of Embodiment 1 of this invention. It is a conceptual diagram which shows the structure of the inner hook accommodating part and X link which show Embodiment 1 of this invention.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 Outer frame, 2 Inner hook accommodating part, 2a Air layer, 3 Bottom surface, 4 Temperature detection apparatus, 5 Induction heating coil, 6 Ferrite, 7 Coil cover, 8 Bottom, 9 Intake hole, 10 Exhaust hole, 11 Cooling fan, 12 control body, 13 body cover, 15 lid part, 16 lid heater, 17 heat sink, 18 spring, 19 hook button, 20 inner hook, 60 tubular actuator, 61 fixing member, 62 trunk heater, 65 mating part, 65a clearance, 70 X Link, 71 Wall side support, 72 Spring, 73 axis, 74 Solenoid, 75 fulcrum.

Claims (6)

A rice cooker body having a main heating part at the bottom;
An inner pot that is detachably stored in the rice cooker body,
A cylindrical inner hook storage portion that covers the outer periphery of the inner hook via a predetermined gap and is deformable in the radial direction;
Auxiliary heating means attached to the side surface of the inner pot storage part,
Movable means for releasing the close contact or the close contact of the inner hook housing portion with the inner pot in synchronization with the heating operation of the auxiliary heating means;
Control means for controlling the heating operation of the auxiliary heating means under a predetermined condition by driving and controlling the main heating unit to execute a rice cooking process including a preheating process, a boiling process, and a steaming process. ,
The control means includes
In the preheating step, the movable means does not operate the auxiliary heating means so that the inner hook housing portion does not contact the inner hook,
In the boiling step and the steaming step, the auxiliary heating means is heated so that the movable means has a heating amount enough to bring the inner pot housing portion into close contact with the inner pot,
In the final stage of the steaming step, the auxiliary heating means is heated so that the movable means has a heating amount enough to release the close contact between the inner pot housing portion and the inner pot. vessel.   2. The rice cooker according to claim 1, wherein the movable means is provided along a circumferential direction of the inner pot storage portion, and the length thereof is shortened based on a heating operation of the auxiliary heating means.   The rice cooker according to claim 1 or 2, wherein the movable means is made of a shape memory alloy.   The rice cooker according to any one of claims 1 to 3, wherein the inner pot storage portion is made of metal.   5. The rice cooker according to claim 1, wherein in the boiling step, the control means causes the auxiliary heating means to perform heating operation intermittently at a predetermined cycle. The rice cooking step includes a heat retaining step for maintaining the inner pot at a predetermined temperature,
The movable means is composed of a member whose shape changes according to its own temperature,
Temperature detecting means for detecting the temperature of the inner pot,
The control means causes the auxiliary heating means to perform a heating operation when the output of the temperature detection means is equal to or lower than a predetermined value in the heat retention step ,
6. The rice cooker according to claim 1, wherein when the temperature of the movable unit becomes equal to or higher than a predetermined threshold, the shape is changed to closely contact the inner pot storage portion with the inner pot. vessel.

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