JP3829763B2 - Cooked rice incubator - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
TECHNICAL FIELD The present invention relates to a cooked rice warmer (including a cooker having a warming function) that improves the warmed state of cooked rice used for general households or business use.
[0002]
[Prior art]
The conventional rice cooker is configured to stop energizing the heating means when the cooking is finished and the temperature is kept, and the temperature is lowered to a predetermined temperature and kept warm. Fatty acid oxidizes to form ketones and aldehydes, causing unpleasant odors and yellowing of cooked rice. One method for suppressing the unpleasant odors and yellowing of cooked rice As a rice cooker, a device that reduces the oxygen concentration causing unpleasant odor and yellowing of cooked rice has been developed.
[0003]
As a rice cooker having this type of function, there is one disclosed in JP-A-11-137424. As shown in FIG. 6, this cooked rice warmer has a configuration in which an oxygen removing means 3 is arranged between a lid 1 of the cooked rice warmer and an inner lid 2 attached to the lid 1. Means 3 uses a nitrogen-enriched air supply device composed of a compressor and molecular sieve charcoal. The nitrogen-enriched air supply device as the oxygen removing means 3 supplies nitrogen-enriched air from the opening 4 to the heat-retaining space of the cooked rice surrounded by the pan 5 and the inner lid 2 to reduce the oxygen concentration. . As shown in FIG. 7, the nitrogen-enriched air supply device as the oxygen removing means 3 includes a compressor 6, molecular sieve charcoal 7, a nitrogen-enriched air supply port 8, an oxygen exhaust port 9, and a plurality of valves 10 for switching the flow path. It consists of When the air compressed by the compressor 6 passes through the molecular sieve charcoal 7, it adsorbs oxygen molecules, thereby generating nitrogen-enriched air at the nitrogen-enriched air supply port, while the molecular sieve 7 has an oxygen adsorption capacity. Reaches the limit, the valve 10 is switched to release oxygen-enriched air to the oxygen exhaust port 9. The generated nitrogen-enriched air is caused to flow from the opening 4 of the cooked rice warmer in FIG. 6 into the warmed space, thereby reducing the oxygen concentration in the warmed space, generating unpleasant odor caused by oxygen, and warmed cooked rice. It is possible to suppress yellowing.
[0004]
[Problems to be solved by the invention]
However, in the above conventional configuration, the oxygen adsorption efficiency of the molecular sieve charcoal 7 constituting the nitrogen-enriched supply device used as the oxygen removing means 3 is low, so the oxygen concentration in the heat retaining space of the rice incubator is reduced. It took a long time to make it occur, and there was a problem that it was difficult to prevent the odor and yellowing of the heated cooked rice due to the reaction between the remaining oxygen and the cooked cooked rice during that time.
[0005]
Moreover, since a large number of valves 10 for switching between the compressor 6 and the flow path are necessary to obtain nitrogen-enriched air, the apparatus itself becomes large, and the lid 1 is required to be stored in the lid 1 of the rice cooker. There was a problem that the rice cooker itself would be large.
[0006]
Furthermore, since the compressor 6 is used, noise during operation is high, and there is a concern about unpleasantness such as noise during operation at night.
[0007]
The present invention solves such a conventional problem, and provides a cooked rice warmer that reduces the oxygen concentration in the warming space during the warming of cooked rice and suppresses the generation of unpleasant odors and the yellowing of cooked rice. The purpose is to do.
[0008]
[Means for Solving the Problems]
In order to solve the above-described conventional problems, the cooked rice warmer of the present invention includes an oxygen removing means provided with an oxygen pump element that contains a metal oxide that removes oxygen contained in a heat retaining space and has oxygen ion conductivity. The flow hole for allowing the air contained in the heat retaining space to flow in and the opening / closing means for opening and closing the flow hole are provided . Since only oxygen molecules can be removed by using an oxygen pump element made of metal oxide and having oxygen ion conductivity as oxygen removing means, the oxygen concentration in the heat insulation space can be reduced to several percent in a short time. It is possible to remarkably suppress the generation of unpleasant odors from the heated cooked rice and the yellowing of the cooked rice.
[0009]
In addition, since oxygen molecules that are naturally diffused by the oxygen pump element itself can be transported as oxygen ions, a device such as a compressor is not required, and a small size, light weight, and low noise can be realized.
[0010]
Further, since warm air in the heat insulation space can pass through the circulation hole provided in the inner lid by the upward flow, the contact of the air with the oxygen removing means easily occurs, and the oxygen removal rate can be improved.
[0011]
In addition, in rice cookers having a heat retaining function, the inside of the lid body and oxygen removing means can be prevented by closing the circulation hole with the opening and closing means during rice cooking, thereby preventing invasion of the rice cracker generated during rice cooking. Thus, it is possible to maintain a clean state at all times and to maintain the performance of the oxygen removing means for a long time.
[0012]
DETAILED DESCRIPTION OF THE INVENTION
The invention according to claim 1 is a main body, a detachable pot accommodated in the main body, a lid body having an inner lid that opens and closes an upper surface opening of the main body, the main body, and the lid a heating means for heating said pan provided in the body, the pot and the oxygen pump element having a metal oxide containing oxygen ion conductivity for removing oxygen contained in the air in the insulation space surrounded by the lid The oxygen ion is formed of a metal oxide by providing a flow hole for allowing the air in the heat retaining space to flow into the inner lid and an opening / closing means for opening and closing the flow hole. By using an oxygen removing means composed of an oxygen pump element having conductivity, oxygen molecules in the warm air can be transported as oxygen ions, and oxygen molecules can be released from the pump element. acid It becomes possible to remove only molecules, and since the oxygen concentration in the heat insulation space can be reduced to several percent in a short time, the generation of unpleasant odor from the heat insulation rice and the yellow change of the rice can be significantly suppressed, Even if the cooked rice is kept warm for a long time, it can be kept delicious.
[0013]
Further, since warm air in the heat insulation space can pass through the circulation hole provided in the inner lid by the upward flow, the contact of the air with the oxygen removing means easily occurs, and the oxygen removal rate can be improved.
[0014]
In addition, in rice cookers having a heat retaining function, the inside of the lid body and oxygen removing means can be prevented by closing the circulation hole with the opening and closing means during rice cooking, thereby preventing invasion of the rice cracker generated during rice cooking. Thus, it is possible to maintain a clean state at all times and to maintain the performance of the oxygen removing means for a long time.
[0015]
In the invention according to claim 2 , in particular, when the oxygen concentration in the heat insulation space is lower than the concentration at which the reaction between cooked rice and oxygen does not proceed by the opening and closing means according to claim 1, the circulation hole is closed, and the reaction between the cooked rice and oxygen proceeds. When the concentration is higher than the concentration that is not used, the oxygen removal means can be stopped until the oxygen concentration in the heat insulation space increases due to the inflow of air from the other by operating to open the flow hole, so that power consumption is reduced. Thus, energy saving can be achieved.
[0016]
【Example】
Embodiments of the present invention will be described below with reference to the drawings.
[0017]
Example 1
FIG. 1 is a cross-sectional view of the whole structure showing a cooked rice warmer in a first embodiment of the present invention. In FIG. 1, the cooked rice warmer is composed of a main body 11, a lid body 12 that opens and closes the upper surface opening of the main body 11, and a detachable pan 13 that is housed in the main body 11. An inner lid 14 is attached to 12. The bottom and side portions of the main body 11 are provided with a bottom heating means 15 comprising an induction heating coil for heating the bottom of the pan 13 and a side heating means 16 comprising an induction heating coil for heating the side portion of the pan 13. Yes. Reference numeral 17 denotes cooked rice that has been kept warm, and a space surrounded by the pan 13, the inner lid 14, and the cooked rice 17 is a warm space 18. Reference numeral 19 denotes oxygen removing means composed of an oxygen pump element having oxygen ion conductivity made of a metal oxide that removes oxygen contained in the air in the heat retaining space 18, and 20 denotes air removing means from the heat retaining space 18. 19 is a flow hole provided in the inner lid 14 that flows into the inner lid 14.
[0018]
FIG. 2 is a cross-sectional view showing a specific configuration of the oxygen removing means 19 of the present invention. In FIG. 2, reference numeral 21 denotes an oxygen pump element. The oxygen pump element 21 has a first electrode 23 formed on one surface of a substrate 22 made of metal oxide and having oxygen ion conductivity, and a second electrode 24 formed on the other surface. The oxygen pump drive power supply 25 that applies a DC voltage to the oxygen pump element 21 is connected via lead wires 26 and 27.
[0019]
As the substrate 22 having oxygen ion conductivity, zirconia doped with yttrium (YSZ) or ceria doped with samarium (SDC) is used. Further, as the first electrode 23 and the second electrode 24, a printing film or a vapor deposition film such as a composite metal oxide (SSCO) composed of platinum (Pt), silver (Ag), and samarium-strontium-cobalt is used. When the first electrode 23 acts as a cathode electrode, the second electrode 24 acts as an anode electrode. 28 is a partition means for partitioning the space on the first electrode 23 side and the space on the second electrode 24 side, has an opening facing the first electrode 23, and is bonded to the oxygen pump element 21 by an adhesive material such as glass. Has been.
[0020]
In this embodiment, the partition means 28 is disposed on the first electrode 23 side, but may be disposed on the second electrode 24 side. A suitable material for the partition means 28 is a metal plate or foil such as nickel, iron-chromium alloy, titanium, gold, platinum, or a ceramic plate such as alumina or mullite, but has a small difference in thermal expansion from the oxygen pump element 21. Since the thermal strain is required to be small, nickel or iron-chromium alloy metal foil is desirable. 29 is a heating means provided below the oxygen pump element 21 and is connected to a heating power source 30 for applying electric power to the heating means 29 via lead wires 31 and 32, and the oxygen pump element 21 and the partition means. The oxygen pump element 21 and the partition means 28 are disposed below the oxygen pump element 21 and the partitioning means 28 so as to face at least one of the surfaces. Reference numerals 33 and 34 denote heat insulating materials having a ventilation function, which are composed of a porous body having a large number of communication holes, and are arranged so as to cover the periphery of the oxygen pump element 21, the partition means 28, and the heating means 29, and The heat insulating materials 33 and 34 having the above are housed in a casing 35 provided with an opening so that air from the atmosphere and oxygen can flow out to the atmosphere. As the heat insulating materials 33 and 34 having the ventilation function, an aggregate of silica particles whose main component is an inorganic oxide is used.
[0021]
The operation and action of the cooked rice warmer having the oxygen removing means configured as described above will be described below.
[0022]
When the cooked rice 17 is kept at a temperature of about 70 ° C. by the bottom heating means 15 and the side surface heating means 16, power is first supplied by the heating power source 30 of the oxygen removing means 19 in response to a command from a control circuit (not shown). Supplyed to the heating means 29, the oxygen pump element 21 is heated.
[0023]
Next, a voltage is applied to the oxygen pump element 21 by the oxygen pump drive power supply 25 with the first electrode 23 as a cathode and the second electrode 24 as an anode. When the oxygen pump element 21 is heated to 500 to 800 ° C. by the heating means 29, oxygen molecules existing in the space on the first electrode 23 side are taken from the first electrode 23 into the substrate 22 having oxygen ion conductivity as oxygen ions. To the second electrode 24. Oxygen ions that have reached the second electrode 24 become oxygen molecules and are released into the space on the second electrode 24 side. Since the partition means 28 that partitions the space on the first electrode 23 side and the space on the second electrode 24 side suppresses the movement (back flow) of oxygen present on the second electrode 24 side to the first electrode 23 side. Since the oxygen concentration on the 1 electrode 23 side gradually decreases, as shown by the arrow in FIG. 1, the air containing oxygen molecules in the heat retaining space 18 that has passed through the circulation hole 20 has a communication hole of the heat insulating material 33 having a ventilation function. It diffuses and flows into the space on the first electrode 23 side.
[0024]
On the other hand, oxygen molecules released from the second electrode 24 diffuse from the space on the second electrode 24 side through the heat insulating material 34 having a ventilation function and flow out into the atmosphere. As a result, while the oxygen pump element 21 is in operation, oxygen molecules in the air continue to be transported as shown by the arrows in FIG. 2, and the oxygen concentration in the heat retaining space 18 of the rice cooker is lowered to a level of several percent. be able to.
[0025]
In this embodiment, the oxygen removing means 19 is composed of an oxygen pump element 21 made of metal oxide and having oxygen ion conductivity, so that oxygen molecules in the warm air are transported as oxygen ions, and oxygen molecules are transferred from the pump element 21. Since only oxygen molecules existing in the heat insulation space can be removed, the oxygen concentration in the heat insulation space can be reduced to several percent in a short time. As a result, it is possible to remarkably suppress the generation of an unpleasant odor and the yellowing of the cooked rice that are caused by exposure to oxygen for a long time as in the past, and it is possible to maintain the deliciousness even during long-time heat insulation. .
[0026]
The oxygen removing means 19 includes an oxygen pump element 21, a partition means 28 for partitioning the space on the first electrode 23 side and the space on the second electrode 24 side formed in the oxygen pump element, and heating for heating the oxygen pump element 21. Since the heat insulating materials 33 and 34 having a ventilation function and disposed around the means 29, the oxygen pump element 21 and the heating means 29 can be constituted by small and small members, a light and small oxygen removing means 19 can be realized. In addition, the oxygen pump element 21 used as the oxygen removing means 19 can ionize and remove naturally diffused oxygen molecules, so that the main body 11 of the insulated rice cooker can be easily moved into the main body 11 without enlarging it. Can be mounted on. Further, since no air blowing means such as a compressor is required, low noise can be realized.
[0027]
Further, by providing a flow hole 20 in the inner lid 14 attached to the lid body 12 and disposing the oxygen removing means 19 between the lid body 12 and the inner lid 14, the warm air in the heat retaining space 18 is caused by upward flow. Since the flow hole 20 provided in the inner lid 14 can be passed, the contact of air with the oxygen removing means 19 occurs easily, and the oxygen removal rate can be improved. Further, since the oxygen removing means 19 is not directly touched during operations such as taking in and out of cooked rice and pans, damage and contamination can be prevented and high reliability can be realized.
[0028]
In addition, although the one demonstrated in the Example the structure provided with the through-hole 20, the number of the through-holes 20 is not used at present, and multiple can also be provided.
[0029]
(Example 2)
FIG. 3 is a cross-sectional view of a main part of the cooked rice warmer in the second embodiment of the present invention. 3, the same components as those in FIGS. 1 and 2 of the first embodiment are denoted by the same reference numerals, and description thereof is omitted. In FIG. 3, the oxygen pump drive power source 25, the lead wires 26 and 27, the heating power source 30, and the lead wires 31 and 32 described in FIG. 2 are omitted.
[0030]
As shown in FIG. 3, the difference from the first embodiment is between the oxygen removing means 19 disposed inside the lid 12 and the flow hole 20 provided in the inner lid 14 attached to the lid 12. The flow passage 36 for introducing the air flowing in from the circulation hole 20 into the oxygen removing means 19 is provided. The flow passage 36 is formed by a partition 37 provided so as to connect the lid body 12 and the inner lid 12.
[0031]
With this configuration, since the air in the heat retaining space 18 can be efficiently introduced into the oxygen removing means 19, the oxygen removal rate in the heat retaining space 18 can be improved. Moreover, since the air which contacts the oxygen removal means 19 is interrupted | blocked from air | atmosphere by the flow path 35, the inflow of air from air | atmosphere can be prevented, Therefore The removal speed of the oxygen of the heat retention space 18 can be improved more.
[0032]
Example 3
FIG. 4 is a cross-sectional view of the main part of the cooked rice warmer in the third embodiment of the present invention. 4, the same components as those in FIGS. 1 and 2 of the first embodiment are denoted by the same reference numerals, and description thereof is omitted. In FIG. 4, the oxygen pump drive power source 25, the lead wires 26 and 27, the heating power source 30, and the lead wires 31 and 32 described in FIG. 2 are omitted.
[0033]
As shown in FIG. 4, the difference from the configuration of the first embodiment is that an opening / closing means 38 that opens and closes the circulation hole 20 through which the air in the heat retaining space 18 provided in the inner lid 14 passes is provided. In the opening / closing hand 38, an opening / closing valve 39 is connected to a support means 40. The support means 40 extends to the outside of the flow passage 36 and the oxygen removing means 19, and is fixed to the lid 12 together with the spring 41.
[0034]
FIG. 4 shows a state in which the oxygen removing means 19 is in operation when the cooked rice is kept warm, and the opening / closing means 38 is in a state in which the flow hole 20 is opened. The opening / closing means 38 operates a drive mechanism (not shown) such as a cam, whereby the spring 41 is returned, and the support means 40 and the opening / closing valve 39 attached to the tip of the support means 40 are moved upward to flow. Hole 20 is opened. When the oxygen removing means 19 is operated in this state, the air in the heat retaining space 18 is guided to the oxygen removing means 19 through the flow holes 20 as indicated by arrows in the figure, and the oxygen in the heat retaining space 18 is removed.
[0035]
On the other hand, when the cooked rice is not warmed or cooked with a rice cooker having a heat retaining function, the opening / closing means 38 is actuated by a drive mechanism such as a cam, and the spring 41 is pushed to move the support means 40 and the opening / closing valve 39 downward. The flow hole 20 is closed.
[0036]
In the present embodiment, in the rice cooker having a heat retaining function, it is possible to prevent the inside of the lid from entering into the lid during rice cooking by closing the flow hole 20 from the opening / closing means 38 during rice cooking. The inside of the lid 12 and the oxygen removing means 19 are not contaminated and can always be kept clean. In addition, the performance of the oxygen removing means 19 due to foreign matter can be prevented from being deteriorated, and the initial performance can be maintained for a long time. can do.
[0037]
In addition, when the oxygen removal means 19 reaches the concentration at which the reaction between the cooked rice and oxygen does not proceed with the oxygen removal means 19 in the state where the cooked rice is kept warm, it is not necessary to operate the oxygen removal means 19 any further, so the oxygen removal means 19 At the same time, the opening / closing means 38 is operated to close the flow hole 20.
[0038]
Thereafter, when the oxygen concentration in the heat retaining space 18 increases to a concentration at which the reaction proceeds due to the inflow of air from the other, the oxygen removing means 19 is actuated again, and the opening / closing means 38 opens the circulation hole 20 to remove oxygen in the heat retaining space 18. . When the oxygen removing means 19 is stopped, the opening / closing means 38 is operated to close the circulation hole 20 because the oxygen concentration in the heat retaining space 18 is reduced from the oxygen removing means 19 and the gap between the lid 12 and the inner lid 14 to the atmosphere. This is to suppress the inflow of the air therein and to slow the increase rate of the oxygen concentration in the heat retaining space 18. By closing the flow hole 20 by the on-off valve 38 while the oxygen removing means 19 is stopped, the stop time of the oxygen removing means 19 can be extended, so that power consumption is reduced and energy saving can be achieved. .
[0039]
The oxygen removing means 19 and the opening / closing means 38 can be controlled by a method of detecting the oxygen concentration in the heat retaining space 18 with an oxygen sensor or by obtaining an increasing rate of the oxygen concentration in advance by time.
[0040]
Example 4
FIG. 5 is a cross-sectional view of the main part of the cooked rice warmer in the fourth embodiment of the present invention. In FIG. 5, the same components as those in FIGS. 1 and 2 of the first embodiment are denoted by the same reference numerals, and description thereof is omitted. In FIG. 5, the oxygen pump drive power source 25, the lead wires 26 and 27, the heating power source 30, and the lead wires 31 and 32 described in FIG. 2 are omitted.
[0041]
As shown in FIG. 5, the difference from the configuration of the first embodiment is that the inside of the lid body 12 constituting the cooked rice warmer has an inner lid 15 attached to the lid body 14 and a thermal insulation space 18 surrounded by a pan. The agitating means 42 for agitating the air and the air flowing in from the heat retaining space 18 is provided.
[0042]
The stirring means 42 is composed of a small sirocco fan 43 and a shaft 44 of the sirocco fan 43. The shaft 44 extends to the outside of the flow passage 36 and the oxygen removing means 19, and is fixed to the lid 12. The shaft 44 is a motor. A driving source (not shown) is connected.
[0043]
The stirrer 42 is activated when the oxygen removing stage 19 is in operation, and can promote the diffusion of air in the heat retaining space 18 to the oxygen removing means 19, further improving the oxygen removing performance of the heat retaining space 18. Can be made. As the agitation means 42, any one of a propeller fan and an air pump can be used in addition to the sirocco fan 43, and this can obtain a higher air diffusion effect of the heat insulation space 18 to the oxygen removal means 19. In addition, the oxygen removal rate of the heat retaining space 18 can be improved.
[0044]
The stirring means 42 need not be operated continuously while the oxygen removing means 19 is operating, and may be operated intermittently.
[0045]
【The invention's effect】
As described above, according to the first and second aspects of the invention, since only oxygen molecules in the air in the heat insulation space can be removed, the oxygen concentration in the heat insulation space can be reduced to several percent in a short time. It is possible to remarkably suppress the generation of an unpleasant odor from the heated rice and the yellowing of the cooked rice. In addition, since oxygen molecules that are naturally diffused by the oxygen pump element itself can be transported as oxygen ions, a device such as a compressor is not required, and a small size, light weight, and low noise can be realized.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view showing an overall configuration of a rice cooker in Embodiment 1 of the present invention. FIG. 2 is a cross-sectional view showing a specific configuration of oxygen removing means of the cooked rice warmer. Fig. 4 is a cross-sectional view of the waist portion of the cooked rice warmer according to the second embodiment. Fig. 4 is a cross-sectional view of the waist portion of the cooked rice warmer according to the third embodiment of the present invention. Fig. 6 is a cross-sectional view showing the entire configuration of a conventional rice cooker. Fig. 7 is a block diagram showing a nitrogen-enriched air supply device of the rice cooker.
DESCRIPTION OF SYMBOLS 11 Main body 12 Lid body 13 Pan 14 Inner lid 18 Thermal insulation space 19 Oxygen removal means 20 Flow hole 21 Oxygen pump element 22 Substrate having oxygen ion conductivity 23 First electrode 24 Second electrode 28 Partition means 29 Heating means 33, 34 Ventilation Insulating material having function 36 Flow passage 38 Opening / closing means 42 Stirring means

Claims (2)

A main body, a detachable pot stored in the main body, a lid having an inner lid for opening and closing an upper surface opening of the main body, and the main body and the pan provided on the lid are heated. and heating means, the oxygen removing means provided oxygen pump element having a metal oxide containing oxygen ion conductivity to remove oxygen contained in the air of the pot and the heat insulating space enclosed by the lid with the, A rice cooker provided with a circulation hole for allowing the air in the heat insulation space to flow into the inner lid and an opening / closing means for opening and closing the circulation hole . The opening / closing means is operated to close the circulation hole when the oxygen concentration in the heat insulation space is lower than the concentration at which the reaction between the cooked rice and oxygen does not proceed, and to open the circulation hole when the oxygen concentration is higher than the concentration at which the reaction between the cooked rice and oxygen does not proceed. Item 1. A rice cooker according to item 1 .

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