JPH09266851A - Food heat reserving vessel - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reserve heat with high quality without decomposing food for many hours by arranging a sterilizing means to sterilize the inside of a heat reserving space formed of an inner pot and a cover body in a food heat reserving means to heat and thermally reserve the inner pot to house food. SOLUTION: An electric rice cooker has a rice cooker main body composed of a bottomed cylindrical outer case 1 inside which an inner pot (a rice cooker) 3 can be set and a cover unit 2 to cover an upper part of the outer case 1, and a bottomed cylindrical inner case (a protective frame) to set the inner pot 3 through a heat insulating material 8 so as to be taken in and out, is arranged inside the outer case 1. A heat reserving heater SH is arranged in an inner case side wall part, and a center censor 7 is arranged in a central part of a bottom wall part 6b. On the other hand, the cover unit 2 is formed as a hollow structure having no inner cover, and a sterilizing lamp 21a is installed in a central part of a heat radiating plate 13 through heat insulating packing 22 and a transparent seal cover 21, and boiled rice at heat reserving time can be sterilized.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a heat insulating structure for a food heat insulating container such as an electric rice cooker.

[0002]

2. Description of the Related Art Generally, for example, an electric rice cooker, when the rice cooking process is completed, shifts to a heat retaining process and switches from the rice cooking heater to a heat retaining heater to function as a food heat retaining container for keeping the rice in the inner pot at a predetermined target temperature. It is designed to let you.

[0003]

However, foods such as rice, which are kept warm as described above, have a problem of spoilage with the lapse of heat keeping time.

[0004] This rot becomes more likely to occur as the heat retention temperature becomes lower and the heat retention time becomes longer. In addition, when the lid is opened and food is taken out during the heat retention, sterilization is introduced at that time, and there is a problem that rot is easily promoted.

These problems are, of course, not limited to the heat-retaining process of the electric rice cooker as described above, but are problems common to food heat-insulating containers in general.

[0006]

The present invention has been made for the purpose of solving the above problems, and in order to achieve the above objects, the following effective means for solving the problems is provided. It is equipped with.

[0007] That is, first, the food heat insulating container of the present invention comprises an inner pan for containing food, a lid for covering the opening of the upper part of the inner pan, and a heat insulating means for heating and maintaining the inner pan. In the container, for example, on the back side of the lid, an ultraviolet lamp for sterilizing the food heat retaining space formed by the inner pot and the lid, a sterilizing means such as an ozone generator is provided, and ultraviolet rays of each sterilizing means are provided. The light emission state and the ozone generation state are appropriately controlled in accordance with, for example, the heat retention state of the food (change in temperature, elapsed time, etc.) to sterilize the food.

[0008] The ultraviolet rays generated by the discharge of the ultraviolet lamp and the ozone generated by the discharge of the ozone generator have a high sterilizing action against the spoilage bacteria, and the generation timing and the generation amount of them depend on the change of the heat retention temperature of the food and the heat retention time. It is possible to provide a high-quality food with extremely low spoilage degree even if the temperature is kept at a low temperature of, for example, 70 to 65 ° C. for a long time if the generation level of the spoilage bacteria is appropriately controlled according to the progress. become.

The ultraviolet rays emitted from the ultraviolet lamp also have a function of generating ozone, and the sterilizing effect of ozone is realized in addition to the sterilizing effect of the ultraviolet rays themselves. The ozone generated by the ozone generator and the ozone generated by ultraviolet rays also have a deodorizing effect and absorb the odor of rice.

Appropriate control of the ultraviolet light emission timing and light emission amount, the ozone generation timing and generation amount, etc. according to the change in the heat retention temperature and the elapse of the heat retention time is performed by, for example, the same ultraviolet lamp or ozone generator. The sterilizing means can also be effectively realized by intermittently controlling the drive at a constant cycle, but more preferably, the heat retaining temperature is low when the heat retaining temperature is low according to, for example, a change in the heat retaining temperature of food. Drive control intermittently with a shorter cycle or higher output than when it is high, or intermittently with a shorter cycle or higher output when the heat retention time is longer than the time when the heat retention time is short as the heat retention time elapses. By doing so, it becomes possible to realize more appropriate sterilization control according to the actual degree of spoilage of food.

Further, in this case, a lid opening / closing detecting means for detecting the open / closed state of the lid provided with sterilizing means such as the ultraviolet lamp and the ozone generator is provided, and the sterilization is performed when the lid is opened. By stopping the driving of the means and driving it when the lid is closed, it is possible to ensure safety to the user when the lid is opened and prevent unnecessary power consumption. On the other hand, if the drive output of the sterilizing means, which is started when the lid is closed, is set to a higher output than the drive output in the steady state, the sterilization that has penetrated into the food due to opening can be accelerated. Since it can be destroyed, it becomes possible to make corruption less likely to occur.

If these configurations are adopted in the heat retention process of an electric rice cooker and the sterilization control as described above is performed from the time when the temperature has dropped to a predetermined temperature at which spoilage may occur,
Since the food can be kept warm at the lowest possible temperature, for example, it is possible to prevent the rice from drying while keeping warm and to prevent the occurrence of shavings, so that good heat retaining performance can be realized for a long time.

[0013]

As a result of the above, according to the food heat insulation container of the present invention, high quality heat insulation performance which does not cause spoilage for a long time and which does not deteriorate the original properties of the food Will be able to provide the food heat insulation container.

[0014]

[Embodiment]

(Embodiment 1) Hereinafter, with reference to the accompanying drawings, first, the configuration and operation of a food heat insulating container according to Embodiment 1 of the present invention will be described.

First, FIG. 1 shows the structure of the main body of an electric rice cooker which is a kind of the food heat insulating container.

The electric rice cooker of the present embodiment is formed of, for example, a heater heating type, and serves both as rice cooker and heat retainer. The electric rice cooker comprises a bottomed cylindrical outer case 1 configured so that an inner pan (rice cooker) 3 can be set therein, and a lid unit 2 for covering the upper part of the outer case 1. Equipped with a rice cooker body.

The outer case 1 is composed of a bottomed cylindrical cover member 4 made of synthetic resin, and a synthetic resin shoulder member 5 joined to the upper end of the cover member 4, and the inside thereof. Is provided with a bottomed cylindrical inner case (protective frame) 6 for removably setting the inner pot 3 via a heat insulating material 8.

The inner case 6 is made of a cylindrical thin metal plate having a bottom, and the upper end of the inner case 6 is engaged with the shoulder member 5. The heat retaining heater SH contacts the side wall portion 6a of the inner case 6, and the sensor portion 7a contacts the center portion of the bottom wall portion 6b with respect to the bottom center portion of the inner pot 3 as described later. A center sensor 7 is provided.

The center sensor 7 has a thermistor Tm as a temperature detecting sensor for detecting the temperature of the inner pot 3, that is, the temperature of the rice, and an inner pot set sensor for detecting whether or not the inner pot 3 is set. A sensor portion 7a accommodating an inner pot detection sensor 71 and the like is provided so as to be able to move up and down.

On the upper surface side of the bottom wall portion 6b of the inner case,
A heater plate 9 having a rice-cooking heater MH as a rice-cooking heating means is installed so as to surround the sensor portion 7a of the center sensor 7. The heater plate 9 is in close contact with the bottom surface of the inner pot 3 set in the inner case 6 so as to heat the bottom portion 3a of the inner pot 3 and the outer periphery thereof with good heat conductivity.

On the other hand, the lid unit 2 has an outer cover 10 made of synthetic resin which constitutes an outer peripheral surface thereof, and an inner cover (poly cover) made of synthetic resin which constitutes an outer peripheral annular frame portion on an inner peripheral surface of the outer cover 10. 11 and a heat radiating plate 13 that detachably covers the opening on the inner side in the radial direction of the inner cover 11 via a poly-cover packing 12 having a V-shaped cross section, to form a hollow structure without an inner lid as shown in the figure. Has been done. A sterilizing lamp 21a is attached to the central portion of the heat radiating plate 13 via a heat insulating packing 22 and a transparent seal cover 21 so as to sterilize the cooked rice. The sterilization lamp 21a is, for example, an ultraviolet lamp that emits ultraviolet light having a wavelength of about 2600Å, and a reflection plate 23 that reflects the ultraviolet light is provided around the seal cover 21. Also, reference numeral 1
Reference numeral 6 is a steam escape passage, 20 is a steam discharge pipe fitted in the steam escape passage 16, and FH is a lid heater as a heat dissipation plate heating means for fluffing. The lid heater FH is mounted on the upper surface side of the heat radiating plate 13 with good heat conductivity by being covered with a heat radiating cover and fixed closely.

The lid unit 2 thus constructed is attached to the rear end side of the shoulder member 5 via the hinge mechanism 14 so as to be vertically rotatable, and its open end (front end) side is attached. Further, the reed switch 1 for turning on / off the sterilization lamp provided on the shoulder member 5 on the outer case 1 side.
A magnet 17 that opens and closes 9 in response to opening and closing operation of the lid unit 2, and a lock mechanism 1 that engages with a predetermined position of the lid unit 2 to maintain the closed state of the lid unit 2.
5 and the like are provided. The reed switch 18 and the magnet 17 form a power source opening / closing means of a sterilization lamp lighting circuit (FIG. 3) as a sterilization control device described later and an opening / closing detection means of the lid unit 2.

Further, between the inner case 6 and the outer case 1 on the front side of the rice cooker body, the amount of electricity supplied to the rice cooking heater MH, the lid heater FH, the warming heater SH, etc. is controlled, and the sterilization lamp 2 is provided.
A control board 29 including a control unit (hereinafter, referred to as a microcomputer control unit) including a microcomputer for performing the lighting control of 1a is accommodated. Also,
A front side of the shoulder member 5 is obliquely lowered and provided with a wide operation panel 30 as illustrated. The operation panel 30 includes various switches (menu, heat retention, start, separate rice, timer, etc.) necessary for rice cooking, a rice cooking menu selected by each of these switches, switch operation states, and switch operation settings. A display unit (not shown) for displaying the level and the like for visual recognition by the user is provided.

Next, based on the electric circuit diagram shown in FIG. 2, the overall structure of the electric control circuit portion in the electric rice cooker will be described. Note that, in FIG. 2, parts corresponding to the respective parts shown in FIG. 1 are denoted by the same reference numerals.

First, the electric power from the commercial AC power supply 29 is supplied to the rice cooking heater MH, the warming heater SH and the lid heater F through the temperature fuse 30 which detects and abnormally heats the inner pot 3.
While being supplied to H, each is stepped down by the step-down transformer 35, rectified by the rectifier 36, and supplied to the microcomputer control unit 25 as its power supply. The configuration and operation of the microcomputer control unit 25 will be described later.

The rice cooking heater MH, the heat retaining heater SH and the lid heater FH are connected in parallel with each other. Further, the normally open contact 31 of the relay 31 is connected in series with the rice cooking heater MH.
a is connected. Relay coil 3 of this relay 31
1b is a switching transistor 3 which is ON / OFF controlled by a command from the microcomputer control unit 25.
7, the excitation / demagnetization state is controlled respectively. Reference numeral 32 is a diode for absorbing a counter electromotive force generated when the relay coil 31b is demagnetized.

Triacs 33 and 34 are connected between the heat-retaining heater SH and the commercial AC power supply 29 and between the lid heater FH and the commercial AC power supply 29, respectively. The gates of these triacs 33, 34 are turned on / off by a command from the microcomputer control unit 25.
The microcomputer control unit 25, to which the gate control signals from the controlled switching transistors 38 and 39 are given, operates based on the clock signal from the reference frequency generation circuit (OSC) 40, and the switching transistors 37 according to a predetermined program. , 38, 39 are controlled to control the power supply to the rice cooking heater MH, the heat retaining heater SH and the lid heater FH according to a predetermined rice cooking / heat retaining characteristic. This power supply control is performed based on the output signal from the thermistor Tm of the sensor section 7a provided in the center sensor 7. Reference numeral 71 is an inner pot detection sensor for detecting whether or not the inner pot 3 is set.

On the other hand, when the rice cooking process is completed and the warming process is started, the warming heater SH based on the above predetermined warming characteristic is used.
In addition to the predetermined power supply control, the sterilization lamp lighting circuit 61 of FIG. 3 that functions as a sterilization control device using the temperature of the rice (the inner pot temperature) at that time as a parameter is operated to perform a predetermined cycle of the sterilization lamp 21a as described below. ON, O at output
Perform sterilization control by FF.

Furthermore, the microcomputer control unit 2 is also used.
5 includes various switches 41 to 4 of the operation panel 30 section.
5, liquid crystal display 53, notification buzzer 7 for notifying completion of rice cooking
3 are connected. The microcomputer control unit 25 constitutes the intermittent drive control means of the sterilizing means in the claims.

The sterilization lamp lighting circuit 61 as the sterilization control device is constructed, for example, as shown in FIG.

As shown in FIGS. 2 to 3, the lighting circuit includes a power supply fuse 3 of the commercial AC power supply 29 shown in FIG.
0 through the circuit section, and the reed switch 19 described above.
A power supply circuit is configured by connecting the step-down transformer 62 via the.

A diode bridge 63 and a smoothing capacitor 6 are provided on the secondary side of the step-down transformer 62 of the power supply circuit.
The oscillating circuit 65 for lighting the sterilization lamp 21a and the boosting circuit 66 are connected via the circuit 4.

The oscillation circuit 65 has an oscillation cycle setting means 69 controlled by the microcomputer control unit 25.
Oscillates at the set cycle of and outputs it (see Fig. 5)
Is supplied to the discharge electrode of the sterilization lamp 21a via the booster circuit 66 to blink the lamp 21a.

The sterilization lamp 21a is turned on when an operation control signal (H signal) is supplied from the microcomputer control unit 25 to the oscillation circuit 65. For example, as shown in FIG. 5, the operation control signal is output when the rice cooking process is completed and the heat retention process is started, and the temperature of the inner pot 3 detected by the thermistor Tm becomes equal to or lower than the set temperature. Then, sterilization control of rice in the heat retaining state is executed thereby. Of course, in addition to this, for example, a configuration may be adopted in which the heating process is started and the lighting control is started in synchronization with lighting of the warming lamp.

Next, the flow chart of FIG. 4 shows the contents of the sterilization control according to the first embodiment of the present invention performed by the microcomputer control unit 25.

That is, first, when the heat retention step is entered as described above, the heat retention lamp is turned on in step S ₁ to indicate that it is in the heat retention state. Next, to confirm that thermal insulation switch in step S ₂ is ON, the when OFF ends the insulation control OFF the insulation lamp.

Then, in step S ₃ , it is determined whether or not the temperature of the inner pot 3 has dropped to a sterilization lamp lighting control start temperature of 72 ° C. or lower.

As a result, when the inner pot temperature determined to be NO has not dropped to the same temperature of 72 ° C., in step S ₄ , the heat retaining heater SH is kept OFF to promote the lowering of the inner pot temperature, while In S ₅ , the lid heater FH is turned on at a duty ratio of 7/14 (7 seconds for 14 seconds), and the heat dissipation plate 13 of the lid unit 2 is accompanied by a decrease in the heat retention temperature.
The tsuyu (condensed droplets) generated on the back surface are evaporated.

On the other hand, when the temperature of the inner pot 3 determined to be YES has fallen to the sterilization lamp lighting control start temperature 72 ° C. or lower, the sterilization lamp 21a as shown in FIG.
Were the T _B seconds ON, further determines whether decreased in step S ₆ until retained temperature 65 ° C. below the temperature of the inner pot 3 is a target. As a result, when the range temperature of the inner pot 3 is still 72 ° C. -66 ° C. NO, as it is OFF warmth heater at step S _7, also similar to the case lid heater of step S ₄ in step S ₈ after oN by the duty ratio of 7/14, the flow proceeds to elapse determination of sterilizing lamp oN time setting timer T _B in step S _11. Then, when the result is NO, the sterilizing lamp 21a at step S ₁₂
Take the OFF time setting timer T _A in step S ₁₃ on resetting, the same germicidal lamps 21a to T _B seconds ON, the process returns to step S _1. As a result, the sterilization lamp 21a is turned on for T _B to sterilize and deodorize the rice.

[0040] On the other hand, when the result is YES, to OFF the sterilizing lamp 21a at step S _14. Then, further proceeds to step S _15, one determines the course of the OFF time setting timer T _A of the sterilizing lamp 21a, when the NO is to maintain the OFF state and returns to step S _1, YES
After resetting the ON time setting timer T _B of the sterilizing lamp 21a at step S _16, the process returns to step S ₁ when.

On the other hand, when the temperature of the inner pot 3 determined to be YES in step S ₆ is lower than the target heat retention temperature of 65 ° C. or below, the process proceeds to step S ₉ and the heat retention heater SH
Is turned on to maintain the target heat retention temperature of 65 ° C., and at step S ₁₀ , the lid heater FH is turned on at a duty ratio 9/14 (9 seconds for 14 seconds) slightly higher than the above to turn on the heat dissipation plate 13. Boil off the boil by heating.

Then, the process further proceeds to step S ₁₁ described above, and it is determined whether the sterilization lamp ON time setting timer T _B of the sterilization lamp 21a has passed.
After resetting the sterilization lamp OFF time setting timer T _A in ₁₂ , the operation of the sterilization lamp ON time setting timer T _B is newly started, the sterilization lamp 21a is turned on in step S ₁₃ , and then the process returns to step S ₁ . .

[0043] On the other hand, in the determination in step S _11, the ON time T _B of the sterilizing lamp 21a is determined YES elapsed, the process proceeds to step S ₁₅ in the OFF sterilizing lamp 21a at step S _14.

[0044] In the step S _15, the germicidal lamp 21a
When the set OFF time T _A of the OFF time setting timer T _A after turning OFF is judged, and when the time T _A has not elapsed, the process returns to step S ₁ and the sterilization lamp 21a is turned OFF. while maintaining the state, when YES is returned to step S ₁ resets the oN time setting timer T _B of sterilizing lamp 21a.

As described above, in the heat retention control of the present embodiment, when the rice cooking process is completed and the heat retention process is started, the transition to the sterilization lamp lighting control start temperature (72 ° C.) is performed as shown in FIG.
As shown in, the sterilization lamp 21a is turned on and off (blinking control), that is, intermittent drive control is executed at constant time intervals T _A , and rice is sterilized and deodorized by ultraviolet rays. Therefore, for example, even if the rice is kept warm at a low temperature of about 70 ° C. to 65 ° C. for a long time, the rice is unlikely to rot and a good quality rice can be provided for a long time.

(Embodiment 2) Next, FIGS. 6 to 8 show sterilization of a food heat insulating container according to a second embodiment of the present invention applied to an electric rice cooker in the same manner as in the above-described first embodiment. The structure and operation of the control device are shown.

In this device, the structure of the sterilization control device section of the first embodiment is such that the sterilization lamp 21a is always turned on at a constant lighting cycle T during the heat retention time, whereas, for example, the time shown in FIG. As shown in the chart, after the transition to the heat retention step, the rice temperature lowering stage (85 ℃ ~ 76 ℃, 75 ℃ ~
71 ° C., 70 ° C. to 66 ° C., 65 ° C. or lower) to shorten the lighting cycle of the sterilization lamp 21 a (T _{1 to} T _{2 to} T ₃
T ₄ ), so that the sterilizing function of the sterilizing lamp 21 a is increased according to the progress level of rotting of rice due to the decrease in temperature.

Therefore, the sterilization lamp 2 of the present embodiment is used.
In the lighting control circuit 1a, for example, as shown in FIG. 6, an oscillating circuit 65 for lighting the sterilization lamp 21a is connected to a control signal output terminal of the microcomputer control unit 25 via an oscillation cycle changing means 70. All other configurations are the same as those in FIG. 3 described above.

Then, the flowchart of FIG. 7 and FIG.
The time chart of shows the contents of heat retention and sterilization control in the sterilization control device of the second embodiment.

That is, as shown in FIG. 8, when the rice cooking process is completed and the heat retaining process is started, first, in step S ₁ of FIG. 7, the heat retaining lamp is turned on to display the heat retaining state.

Then, in a succeeding step S ₂ , it is determined whether or not the temperature of the inner pot 3 is equal to or lower than the first set reference temperature 85 ° C. If NO, the heat retaining heater is turned off in a step S _3.
In step S ₄ , the lid heater is turned on with a duty ratio of 2/14 to lower the temperature of the inner pot 3. Then, when the temperature becomes equal to or lower than the first set reference temperature of 85 ° C. which is YES, the sterilization lamp 21 in the longest first lighting cycle T ₁
The lighting control of a is started, and thereafter, in step S ₅ , it is determined whether or not the temperature of the inner pot 3 has dropped to a second set reference temperature of 75 ° C. or lower for varying the lighting cycle.

As a result, when the temperature of the inner pot 3 determined to be NO is within the range of 85 ° C. to 76 ° C. at which the second set reference temperature is not lower than 75 ° C., in step S ₆ , the heat retaining heater is set. while in the SH to OFF to promote the reduction of the inner pot temperature, in the oN the lid heater FH at a duty ratio 5/14 (5 seconds 14 seconds) heating the heat radiating plate 13 in step S _7, The second set reference temperature 75 ℃
The condensate (condensed liquid droplets) generated on the back surface of the heat dissipation plate 13 of the lid unit 2 is evaporated to reduce white blur of the rice. Thereafter, the process proceeds to step S _8, the longest first lighting period T ₁ seconds of said sterilizing lamp 21a (see FIG. 8)
Determines the passage of, when YES is the sterilizing lamp 21a for t ₁ seconds ON in step S _9. Then, in step S ₂₄
In as long as the OFF warmth switch is not determined to continue the intermittent lighting control of the sterilizing lamp 21a and returns to the step S ₅ again. On the other hand, when NO, sterilization lamp 2
The process returns to step S ₅ without turning on 1a.

On the other hand, when the temperature of the inner pot 3 drops below the second set reference temperature of 75 ° C. (YE in step S ₅₎ .
S), further in step S ₁₀ for the temperature of the inner pot 3 is one rank shorter lighting period third preset reference temperature 70
Determine whether the temperature has dropped below ℃. As a result, after the small degree of decrease of the rice temperature to ON the insulation heater SH small output duty ratio 2/14 (2 seconds 14 seconds) in step S ₁₁ that follows when NO, the step S ₁₂
Then, the lid heater FH is turned on at a duty ratio of 6/14 (6 seconds for 14 seconds) to heat the heat dissipation plate 13 to blow off the boil. Then, in step S ₁₃ , this time, the second longest second lighting cycle T ₂ seconds of the sterilization lamp 21 a (see FIG. 8).
Determining the course of the reference), to t ₁ seconds ON the sterilizing lamp 21a at step S ₁₄ when the YES. Thereafter, the insulation switch proceeds to the same step S ₂₄ OF
Performs F determination, when NO is one which returns to Step S ₅ to S ₁₀ to perform the intermittent lighting control in the second lighting period T _2, when the YES finishes the warmth and sterilization control .

On the other hand, the process proceeds to step S ₁₀ and YES.
If it is determined to be (70 ° C. or lower), further step S ₁₅
Then, it is determined whether or not the temperature of the inner pot 3 is the target heat retention temperature and the temperature has dropped to the fourth set reference temperature 65 ° C. or less for shortening the lighting cycle by 3 ranks.

As a result, when the temperature of the inner pot 3 determined as NO is 70 ° C. to 66 ° C., which is not lower than the fourth set reference temperature 65 ° C., the duty ratio of the heat retaining heater SH is changed in step S _16. It is turned on with a small output of 3/14 (3 seconds for 14 seconds) to accelerate the decrease to the fourth set reference temperature of 65 ° C., and at the step S ₁₇ , the lid heater FH
Is turned on at a duty ratio of 7/14 (7 seconds for 14 seconds) to heat the radiator plate 13, and the fourth set reference temperature 6
The dew (condensed liquid droplets) generated on the back surface of the heat dissipation plate 13 of the lid unit 2 as the temperature is lowered to 5 ° C. is evaporated to prevent white blur of rice. After that, the process proceeds to step S _18, and it is determined whether the third lighting cycle T ₃ seconds of the sterilization lamp 21a, which is the third longest (see FIG. 8), has elapsed. If YES, the sterilization lamp 21a is turned on in step S _19. Turn on for ₁ second. As long as OFF warmth switch is not determined in step S _24,
Third and returns to the step S ₅ ~S ₁₀ ~S ₁₅ again
The intermittent lighting control of the sterilization lamp 21a in the lighting cycle T ₃ of is continued. On the other hand, when NO, turn on the sterilization lamp 21a.
Without the N, the process returns to step S ₅ ~S ₁₀ ~S _15.

On the other hand, when the temperature of the inner pot 3 drops below the fourth set reference temperature of 65 ° C. (YE in step S ₁₅₎ .
S), a lid heater FH in step S ₂₁ with the insulation heater SH to ON at the output of the duty ratio 7/14 (7 seconds 14 seconds) in step S ₂₀ aim to maintain to 65 ° C. for rice temperature It is turned on at a duty ratio of 14/14 (14 seconds for 14 seconds) to heat the heat sink 13 sufficiently to blow off the boil. Thereafter, most short lighting cycle T ₄ seconds of the sterilizing lamp 21a at step S ₂₂ (see FIG. 8)
Determines the passage of, when YES is the sterilizing lamp 21a for t ₁ seconds ON in step S _23. Thereafter, the same process proceeds to step S ₂₆ performs OFF determination warmth switch, intermittent lighting of the fourth lighting cycle T ₄ and returns to step S ₅ ~S ₁₀ ~S ₁₅ when the NO While executing the control, when YES, the heat retention and sterilization control are ended.

As a result, after that, the target heat retention temperature is 65 ° C.
The fourth lighting cycle T ₄
The intermittent lighting control of the sterilization lamp 21a is performed, and appropriate sterilization / deodorization control of rice is continued to effectively keep the rice warm.

As described above, in the heat retention control of the present embodiment, when the rice cooking process is completed and the heat retention process is started, first, as shown in FIG. Intermittent lighting control of the sterilization lamp 21a in the _first lighting cycle T ₁ is started, and then the second, third, and fourth set reference temperatures decrease to 75 ° C. or lower, 70 ° C. or lower, 65 ° C. or lower. In accordance with the above, the lighting cycle is shortened to T ₂ , T ₃ and T ₄ and the lighting is intermittently controlled to sterilize and deodorize the rice with ultraviolet rays. Therefore, even if the final low temperature incubation of about 65 ° C. is performed, the sterilizing / deodorizing function is improved as the heat retaining temperature becomes lower, so that the rice is less likely to rot and the high quality rice can be provided for a long time.

(Embodiment 3) Next, FIGS. 9 to 11 are the same as in Embodiments 1 and 2 above, when the food heat insulation container according to Embodiment 3 of the present invention applied to an electric rice cooker is kept warm. 2 shows the configuration and operation of the sterilization control device in FIG.

In this apparatus, as shown in the time chart of FIG. 8, for example, the structure of the sterilization control device section of the above-mentioned second embodiment is followed by the step of lowering the rice temperature (85 ° C. to
76 ℃, 75 ℃ ~71 ℃, 70 ℃ ~66 ℃, so as to the lighting cycle of the sterilizing lamp 21a shorter _{(T 1 ~T 2 ~T 3 ~T} 4) according to 65 ° C. or less), the temperature Sterilization lamp 21a according to the progress level of decay of rice due to deterioration
While it was designed to enhance the sterilization function,
As shown in the time chart of FIG. 11, the same effect can be obtained by increasing the light emission output (wattage) of the sterilization lamp 21a itself in response to the similar decrease of the rice temperature. It is a thing.

Therefore, the sterilization lamp 2 of this embodiment is used.
In the lighting control circuit 1a, for example, as shown in FIG. 9, the oscillating circuit 65 for lighting the sterilization lamp 21a is connected to the control signal output terminal of the microcomputer control unit 25 via the oscillation output varying means 72. All other configurations are similar to those in FIGS. 3 and 6 described above.

The flow chart of FIG. 10 and the time chart of FIG. 11 show the contents of heat retention and sterilization control in the sterilization control device of the third embodiment.

That is, as shown in the time chart of FIG. 11, when the rice cooking process is completed and the heat retention process is started, first, as shown in FIG.
In step S ₁ of the flowchart of _No. 0, the heat retention lamp is turned on to display that it is in the heat retention state.

Then, in a succeeding step S ₂ , it is determined whether or not the temperature of the inner pot 3 has dropped to a first set reference temperature of 85 ° C. or lower, and if NO, the warming heater is turned off in a step S _3.
In F, also reducing the inner temperature of the pot 3 while evaporating droplets ON the lid heater at a duty ratio of 2/14 at Step S _4. Then, when the temperature of the inner pot 3 of YES becomes equal to or lower than the first set reference temperature 85 ° C. which is the lighting control start temperature, the sterilization lamp 21a has the lowest first lighting output W _1.
The lighting control of is started. Then, further, step S ₅
Then, it is determined whether or not the temperature of the inner pot 3 has dropped to a second set reference temperature of 75 ° C. or lower for varying the output.

As a result, when the temperature of the inner pot 3 which is determined to be NO has not fallen below the second set reference temperature of 75 ° C. and is between 85 ° C. and 76 ° C., the heat retaining heater SH is turned off in step S _6. While facilitating the decrease of the inner pot temperature, the lid heater FH is turned on at a duty ratio of 5/14 (5 seconds for 14 seconds) in step S ₇ , and the heat sink 1 is turned on.
3 is heated to evaporate the lumps (condensed liquid droplets) generated on the back surface of the heat radiating plate 13 of the lid unit 2 when the temperature falls to the second set reference temperature of 75 ° C. to prevent white blur of rice. Thereafter, the process proceeds to step S _8, the sterilizing lamp 21a determines the course of the lighting period T s (see constant ... 11) of the first lowest sterilization lamp 21a at step S ₉ when the YES Turn on the lighting output (wattage) W ₁ for t ₁ seconds. As long as it is not determined OFF thermal insulation switch in step S _24, to continue the intermittent lighting control of the sterilizing lamp 21a and returns to the step S ₅ again. On the other hand, if NO, the process returns to step S ₅ without turning on the sterilization lamp 21 a.

On the other hand, when the temperature of the inner pot 3 drops below the second set reference temperature of 75 ° C. (YE in step S ₅₎ .
S), the inner pot 3 for temperature 2 ranked up the lighting output of 3 in further step S ₁₀ of setting the reference temperature 70
Determine whether the temperature has dropped below ℃. As a result, in the case of NO of 75 ° C. to 71 ° C., in the subsequent step S ₁₁ , the heat retention heater SH is turned on with a small output of the duty ratio 2/14 (2 seconds for 14 seconds) to reduce the degree of decrease in the rice temperature. after the duty ratio lid heater FH in step S ₁₂ 6 /
At 14 (6 seconds for 14 seconds), the heat is turned on to heat the heat radiating plate 13 to blow off the boil. Then, this time to determine the elapse of the lighting period T s of the sterilizing lamp 21a at step S ₁₃ (see FIG. 11), the second lighting output W is the second lowest sterilization lamp 21a at step S ₁₄ when YES Turn on for t ₁ seconds at ₂ . Then, after that, in the same manner as above, step S ₂₄
Willing performs OFF determination of thermal insulation switch, one case of NO, which then returns to step S ₅ to continue the intermittent lighting control in the second lighting output W _2, when YES is the warmth and sterilization End control.

On the other hand, the process proceeds to step S ₁₀ and YES
If it is determined to be (70 ° C. or lower), further step S ₁₅
Then, it is determined whether or not the temperature of the inner pot 3 is the target heat retention temperature and the temperature has dropped to the fourth set reference temperature 65 ° C. or lower for increasing the lighting output by 3 ranks.

As a result, when the temperature of the inner pot 3 which is determined to be NO is at least 70 ° C. to 66 ° C., which is not lower than the fourth set reference temperature of 65 ° C. or higher, the heat retaining heater SH is duty cycled in step S _16. The cover heater FH is turned on with a small output of the ratio 3/14 (3 seconds for 14 seconds) to promote the decrease to the fourth set reference temperature of 65 ° C., while the lid heater FH is operated at the duty ratio of 7/14 in step S _17. (7 for 14 seconds
The heat radiation plate 13 is heated at a temperature of 65 seconds) to evaporate the tsuyu (condensed droplets) generated on the back surface of the heat radiation plate 13 of the lid unit 2 when the temperature falls to the fourth set reference temperature of 65 ° C.
Prevent white blur of rice. Thereafter, the process proceeds to step S _18, the lighting period T s of the sterilizing lamp 21a (see FIG. 8)
If YES, the sterilization lamp 21a is turned on by one rank higher than the second lighting output W ₂ by a third step in step S ₁₉ .
The lighting output W ₃ of is turned on for t ₁ seconds. As long as OFF warmth switch is not determined in step S _24, the third and returns to the step S ₅ ~S ₁₀ ~S ₁₅ again
The intermittent lighting control of the sterilization lamp 21a with the lighting output W ₃ of is continued. On the other hand, when NO, turn on the sterilization lamp 21a.
Without the N, the process returns to step S ₅ ~S ₁₀ ~S _15.

On the other hand, when the temperature of the inner pot 3 drops below the fourth set reference temperature of 65 ° C. (YE in step S ₁₅₎ .
S), a lid heater FH in step S ₂₁ with the insulation heater SH to ON at the output of the duty ratio 7/14 (7 seconds 14 seconds) in step S ₂₀ aim to maintain to 65 ° C. for rice temperature It is turned on at a duty ratio of 14/14 (14 seconds for 14 seconds) to heat the heat sink 13 sufficiently to blow off the boil. Thereafter, t ₁ at step S determines the course of the lighting period T s of the sterilizing lamp 21a (see FIG. 11) at _22, the highest fourth lighting output W ₄ of the sterilizing lamp 21a at step S ₂₃ when the YES Turn on for seconds. Thereafter, performs OFF determination warmth switch proceeds to the same step S _24, step S ₅ to S when the NO
And returns to ₁₀ to S ₁₅ while continuing the intermittent lighting control in the lighting output W ₄ of the fourth, when the YES finishes the warmth and sterilization control.

As a result, after that, the target heat retention temperature is 65 ° C.
In a low temperature heat-retaining state centered on, the sterilization / deodorization control at the highest fourth lighting output W ₄ is continued to effectively keep the rice warm.

As described above, in the heat retention control according to the present embodiment, when the rice cooking process is completed and the heat retention process is started, as shown in FIG. First, the intermittent lighting control of the sterilization lamp 21a with the _first lighting output W ₁ is started, and then the second, third, and fourth lighting controls are performed.
By gradually increasing the lighting output W ₁ , W ₂ , W ₃ , W ₄ as the set reference temperature of 75 ° C. or lower, 70 ° C. or lower, and 65 ° C. or lower, and controlling the lighting intermittently, Rice is sterilized and deodorized by ultraviolet rays. Therefore, even if heat retention is finally performed at a low temperature of about 65 ° C., the lower the heat retention temperature is, the more improved the sterilization / deodorizing function is, so that the rice is less likely to rot and the high quality rice can be provided for a long time.

(Fourth Embodiment) Next, FIG. 12 and FIG.
Shows the configuration and operation of the sterilization control device during heat retention of the food heat insulating container according to the fourth embodiment of the present invention which is applied to the electric rice cooker similarly to the above-described first, second, and third embodiments.

In this apparatus, as in the case of the structure of the sterilization control apparatus section of the third embodiment, for example, as shown in the time chart of FIG. 13, after the shift to the heat retention step, the rice temperature lowering stage (85 ° C. to 76 ° C.). , 75 ° C to 71 ° C, 70 ° C to 66 ° C,
The sterilization function of the sterilization lamp 21a is increased according to the progress level of rotting of rice due to the temperature decrease by sequentially increasing the lighting output of the sterilization lamp 21a according to (65 ° C. or less). The lighting output is varied by changing the duty ratio (energization time) of the oscillation output instead of changing the wattage itself as in the third embodiment.

Therefore, the sterilization lamp 2 of this embodiment is used.
In the lighting control circuit 1a, for example, the oscillation output varying means 72 shown in FIG. 9 is constructed by varying the duty ratio, and the sterilization lamp 21a lighting driving oscillation circuit 65 is controlled by a microcomputer via the oscillation output varying means of the construction. Unit 2
5 is connected to the control signal output terminal. All other configurations are similar to those in FIG. 9 described above.

The flow chart of FIG. 12 and the time chart of FIG. 13 show the contents of heat retention and sterilization control in the sterilization control device of the fourth embodiment.

That is, as shown in FIG. 13, when the rice cooking process is completed and the heat retaining process is started, first, in step S ₁ of the flowchart of FIG. 12, the heat retaining lamp is turned on to display that the heat retaining state is maintained.

Then, in the subsequent step S ₂ , it is determined whether or not the temperature of the inner pot 3 has dropped to the first set reference temperature of 85 ° C. or lower, and if NO, the warming heater is turned off in step S _3.
In F, also reducing the inner temperature of the pot 3 while evaporating droplets ON the lid heater at a duty ratio of 2/14 at Step S _4. Then, from the time when the first set reference temperature becomes 85 ° C. or less of YES, intermittent lighting control of the sterilization lamp 21a is started with the lighting cycle T and the first lighting output duty ratio t ₁ / T, and the subsequent steps In S ₅ , it is determined whether or not the temperature of the inner pot 3 has dropped to a first set reference temperature of 75 ° C. or lower for increasing the lighting output 1 rank of the sterilization lamp 21a.

As a result, when the temperature of the inner pan 3 determined to be NO has not dropped to the second set reference temperature of 75 ° C. or lower and the rice temperature is in the range of 85 ° C. to 76 ° C., step S ₆ is performed. While turning off the heat retention heater SH to promote the decrease of the inner pot temperature to the target heat retention temperature, step S
_{When the} lid heater FH has a duty ratio of 5/14 (14
(5 seconds for 5 seconds), the heat sink 13 is heated to heat the heat sink 13, and the drops (condensed liquid droplets) are generated on the back surface of the heat sink 13 of the lid unit 2 as the second set reference temperature drops to 75 ° C. To evaporate and prevent white blur of rice. Then, step S
Proceed to _8, the sterilizing lamp 21a determines the course of the lighting period T s (see constant ... 13) of the step S ₉ in sterilizing lamp 21a to the first lighting output duty ratio t If YES Turn on for ₁ / T seconds. As long as it is not determined OFF thermal insulation switch in step S _24, the lighting period T to return to the step S ₅ again, intermittent lighting control of the sterilizing lamp 21a of the first lighting output duty ratio t ₁ / T To continue. On the other hand, if NO, the process returns to step S ₅ without turning on the sterilization lamp 21 a.

On the other hand, when the temperature of the inner pot 3 drops below the second set reference temperature of 75 ° C. (YE in step S ₅₎ .
S), further step S ₁₀ in the third order temperature 2 Rankuatsupu lighting output of the sterilizing lamp 21a of the inner pot 3
It is determined whether the set reference temperature of 70 ° C. or less has dropped. As a result, when the NO rice temperature is in the range of 75 ° C. to 71 ° C., the warming heater SH is output at a small output of the duty ratio 2/14 (2 seconds for 14 seconds) in the subsequent step S _11.
After reducing the degree of decrease of the rice temperature to N, the duty ratio 6/14 lid heater FH in step S ₁₂ (14
(6 seconds / second), the heat is turned on to heat the heat sink 13 to blow off the boil. Then, this time to determine the elapse of the lighting period T s of the sterilizing lamp 21a (see FIG. 13) in step S _13, sterilization If YES in step S ₁₄ the lamp 21
a is turned on at the second lighting output duty ratio t ₂ / T seconds which is set one rank higher than the _first lighting output duty ratio t ₁ / T. Thereafter, performs OFF determination warmth switch proceeds to the same step S _24, when NO, returns to step S ₅ to S _10, the lighting period T, the second lighting output duty ratio t ₂ / T While continuing the intermittent lighting control of the sterilization lamp 21a of
At the time of ES, the heat retention and sterilization control are finished.

On the other hand, the process proceeds to step S ₁₀ and YES.
If it is determined to be (70 ° C. or lower), further step S ₁₅
Then, it is determined whether or not the temperature of the inner pot 3 is the target heat retention temperature and the temperature has dropped to the fourth set reference temperature 65 ° C. or lower for increasing the lighting cycle by 3 ranks.

As a result, when the temperature of the inner pan 3 determined to be NO has not dropped to the fourth set reference temperature of 65 ° C. or lower, and the rice temperature is in the range of 70 ° C. to 66 ° C., the above-described step S ₁₆ is performed. Set the heater heater SH to duty ratio 3/14
It is turned on with a small output (3 seconds for 14 seconds) to accelerate the decrease to the fourth set reference temperature of 65 ° C., while step S
_{At 17} , the lid heater FH has a duty ratio of 7/14 (14
(7 seconds per second) to turn on to heat the heat dissipation plate 13, and a drop (condensed droplet) generated on the back surface of the heat dissipation plate 13 of the lid unit 2 as the fourth set reference temperature decreases to 65 ° C. To evaporate and prevent white blur of rice. Then, step S
Proceed to _18, to determine the course of the lighting period of the sterilizing lamp 21a T seconds (see FIG. 13), step S ₁₆ when the YES
The sterilization lamp 21a with the third output duty ratio t ₃ /
Turn on in T seconds. As long as OFF warmth switches at step S ₂₄ is not determined, the step S ₅ again
To S ₁₀ and returns to the to S ₁₅ are lit period T, to continue the intermittent lighting control of the sterilizing lamp 21a at the third output duty ratio t ₃ / T. On the other hand, when NO, the sterilization lamp 21
Without to ON a, returns to step S ₅ ~S ₁₀ ~S _15.

On the other hand, when the temperature of the inner pot 3 drops below the fourth set reference temperature of 65 ° C. (YE in step S ₁₅₎ .
S), a lid heater FH in step S ₂₁ with the insulation heater SH to ON at the output of the duty ratio 7/14 (7 seconds 14 seconds) in step S ₂₀ aim to maintain to 65 ° C. for rice temperature It is turned on at a duty ratio of 14/14 (14 seconds for 14 seconds) to heat the heat sink 13 sufficiently to blow off the boil. Then, to determine the course of the lighting cycle T s of the sterilizing lamp 21a (see FIG. 13) in step S _22, when the result is YES the sterilizing lamp 21a at step S ₂₃ in the fourth output duty ratio t ₄ / T sec Turn it on. Thereafter, performs OFF determination warmth switch proceeds to the same step S _24, when the NO Step S ₅ ~
S ₁₀ to S ₁₅ and returns to be lit period T, while continuing the intermittent lighting control of the sterilizing lamp 21a at the fourth output duty ratio t ₄ / T, If YES finishes the warmth and sterilization control .

As a result, the target preset heat retention temperature is 65 ° C. thereafter.
In a heat-retaining state centered on, the sterilization / deodorization control at the lighting cycle T and the fourth lighting output duty ratio t ₄ / T is continued to effectively keep the rice warm.

As described above, in the heat retention control of the present embodiment, when the rice cooking process is completed and the heat retention process is entered, first, as shown in FIG. Intermittent lighting control of the sterilization lamp 21a at the _first lighting output duty ratio t ₁ / T is started, and thereafter,
As the second, third, and fourth set reference temperatures for varying the lighting output decrease to 75 ° C., 70 ° C., and 65 ° C., the lighting output of the sterilization lamp 21a changes in duty ratio t ₂ / T, t ₃ /
Lighting up is controlled by T, t ₄ / T one rank at a time, and the rice is sterilized and deodorized by ultraviolet rays. Therefore, even if the temperature is finally kept at a low temperature of about 65 ° C., the sterilization / deodorizing function is improved as the heat retention temperature is lowered, so that the rice is less likely to rot and a good quality rice can be provided for a long time.

(Embodiment 5) FIGS. 14 and 15 show
The control content and operation of the sterilization control device for a food heat insulating container according to the fifth embodiment of the present invention applied to an electric rice cooker as in the above-described first, second, third, and fourth embodiments are shown.

In the present embodiment, the same oscillation period changing means as in the above-mentioned Embodiment 2 is adopted, and the elapsed time from the time of shifting to the heat retaining step becomes longer and the rice becomes more apt to decay, By shortening the lighting cycle of the sterilization lamp 21a, the sterilization function by ultraviolet rays is enhanced.

The flowchart of FIG. 14 and the time chart of FIG. 15 show the content of the sterilization control performed by the microcomputer control unit 25 similar to that of FIG.

That is, as shown in FIG. 15, when the rice cooking process is completed and the rice cooking heater is turned off to enter the heat retaining process,
In step S ₁ , the heat retention lamp is first turned on to indicate that the heat retention state is maintained. And at the same time, step S
_{At 2} , the timer ta that counts the elapsed time after the transition to the heat retention step is started.

Next, in step S ₃ , it is determined whether or not the inner pot temperature has dropped to a target set heat retention temperature of 70 ° C. or lower.

As a result, when the temperature of the inner pot determined to be NO has not dropped to the same temperature of 70 ° C., or when it has once dropped but rises above the same temperature of 70 ° C. again, at step S _{4 the} heat retaining heater is set. While controlling the OFF of SH to promote the decrease of the inner pot temperature to the heat retention temperature, in step S ₅ , the lid heater FH is operated with a duty ratio of 7/14 (7 for 14 seconds).
The heat radiation plate 13 is heated for a second time) to heat the heat radiation plate 13 to evaporate the tsuyu (condensed liquid droplets) generated on the back surface of the heat radiation plate 13 of the lid unit 2 as the temperature lowers.

On the other hand, the inner pot temperature is the preset heat retention temperature 7
When the temperature drops to 0 ° C. or less, the warming heater SH is turned on in step S ₆ to raise the rice temperature to maintain the preset warming temperature of 70 ° C., and in step S ₇ , the lid heater FH is driven to a duty ratio of 9/14. (9 seconds for 14 seconds) is turned on to heat the heat sink 13 to remove the blisters on the back surface of the heat sink 13.

Then, the process proceeds to steps S ₈ , S ₉ and S ₁₀ , and the elapsed time t from the time of shifting to the heat retention step is t.
From the count value of the timer ta that counts a, the elapsed time ta = less than 6 hours, 6 hours to less than 12 hours, 1
2 hours to less than 18 hours and 18 hours or more are sequentially judged. Then, the lighting cycle T ₁ , of the sterilization lamp 21a, which is set so as to become shorter in steps S ₁₁ , S ₁₂ , S ₁₃ , and S ₁₄ in accordance with the increase of the elapsed time, respectively.
T _2, to determine the course of T _3, T _4, the respectively to YES, first step _{S 15, S 18, S 21} , lighting cycle sets each at S ₂₄ sets the timer _{T 1, T 2, T 3} , T ₄ after resetting the step to the new _{S 16, S 19, S 22} , S 25 again step by starting the timer operation _{S 17, S 20, S 23} , S
The ON signal of the sterilization lamp 21a having a wattage W (constant) is output at ₂₆ , and each of the elapsed times ta = less than 6 hours, 6 hours-
Less than 12 hours, 12 hours to less than 18 hours, depending on the 18 hours or more, the sterilization lamp 21a to the respective cycles T ₁ , T ₂ ,
In T _3, T _4, are turned in respective t ₁ hour (constant).

On the other hand, the above steps S ₁₁ , S ₁₂ , S ₁₃ ,
The germicidal lamp lighting period is determined in _{S 14 T 1, T 2,} T 3,
When it is determined that each T ₄ has not elapsed, the process proceeds to step S ₂₇ without turning on the sterilization lamp 21a.

[0094] In the step S _27, the germicidal lamp 21a
Insulation switch is OF regardless of ON or OFF of
After determining whether or not the F operation has been performed, the heat insulation switch is turned on.
When the FF is not performed, the operation is returned to step S ₂ and thereafter, and the intermittent lighting control of the sterilization lamp 21a in the lighting cycle corresponding to the elapsed time is continued to sterilize the rice with ultraviolet rays. And prevent corruption.

On the other hand, when the YES heat retention switch is turned off, the above heat retention and sterilization control are all ended.

As a result, when the maximum elapsed time of 18 hours has passed, thereafter, in the heat-retention state centering on the target heat-retention temperature of 70 ° C., the intermittent lighting is intermittently performed in the shortest fourth lighting cycle T _4. The sterilization control is continued to keep the rice warm effectively.

As described above, in the heat retention control of the present embodiment, when the rice cooking process is completed and the heat retention process is started, the heat retention time count timer ta is started, and thereafter, the transition to the set heat retention temperature 70 ° C. is performed. As shown in FIG. 15, first, intermittent lighting control of the sterilization lamp 21a in the _first lighting cycle T ₁ is started, and thereafter, the elapsed time ta from the start of the heat retention step ta = less than 6 hours, 6 hours. ~ Less than 12 hours,
12 hours less than 18 hours, by intermittently lighting control progressively lighting cycle went shortened from the lighting cycle _{T 1, T 2, T 3} , T 4 in accordance with more than 18 hours, the ozone generated by the ultraviolet light and ultraviolet The rice is sterilized and deodorized by. Therefore, as a result, the sterilization function improves as the heat retention time increases even when heat retention is performed at a low temperature of, for example, about 70 ° C., so that the rice is less likely to rot and a good quality rice can be provided for a long time. it can.

(Embodiment 6) FIGS. 16 and 17 show
The control content and operation of the sterilization control device for a food heat insulating container according to Embodiment 6 of the present invention applied to an electric rice cooker as in Embodiments 1, 2, 3, 4, and 5 described above are shown.

In the present embodiment, the same oscillating output varying means as in the third embodiment is adopted, and the sterilization is performed as the elapsed time from the time of shifting to the heat-retaining process becomes longer and the rice is more likely to rot. By increasing the lighting output (wattage) of the lamp 21a, the sterilizing function by ultraviolet rays is enhanced.

The flowchart of FIG. 16 and the time chart of FIG. 17 show the contents of the sterilization control performed by the microcomputer control unit 25 similar to that of FIG.

That is, as shown in FIG. 16, when the rice cooking process is completed and the rice heating heater is turned off to enter the heat retaining process,
In step S ₁ , the heat retention lamp is first turned on to indicate that the heat retention state is maintained. And at the same time, step S
_{At 2} , the timer ta that counts the elapsed time after the transition to the heat retention step is started.

Next, in step S ₃ , it is determined whether or not the inner pot temperature has dropped to a target set heat retention temperature of 70 ° C. or lower.

As a result, when the temperature of the inner pot determined to be NO has not dropped to the same temperature of 70 ° C., or when it has once dropped but rises above the same temperature of 70 ° C. again, at step S _{4 the} heat retaining heater is set. While controlling the OFF of SH to promote the decrease of the inner pot temperature to the heat retention temperature, in step S ₅ , the lid heater FH is operated with a duty ratio of 7/14 (7 for 14 seconds).
The heat radiation plate 13 is heated for a second time) to heat the heat radiation plate 13 to evaporate the tsuyu (condensed liquid droplets) generated on the back surface of the heat radiation plate 13 of the lid unit 2 as the temperature lowers.

On the other hand, the inner pot temperature is the preset heat retention temperature 7
When the temperature drops to 0 ° C. or lower, the warming heater SH is turned on in step S ₆ to raise the rice temperature to maintain the preset warming temperature, and in step S ₇ , the lid heater FH is operated at a duty ratio of 9/14 (14). 9 for second
The heat generated on the heat dissipation plate 13 is turned on for a second time to remove the blisters on the back surface of the heat dissipation plate 13.

Then, the process proceeds to steps S ₈ , S ₉ and S ₁₀ to elapse time t from the time of shifting to the heat retaining step.
From the count value of the timer ta that counts a, the elapsed time ta is less than 6 hours, 6 hours to less than 12 hours, 1
2 hours to less than 18 hours and 18 hours or more are sequentially judged. Then, according to the elapsed time, step S
_11, S _12, to determine the course of the S _13, the lighting period of the sterilizing lamp 21a at S ₁₄ T (T = constant), the respectively to YES, first turned on in step _{S 15, S 18, S 21} , S 24 After resetting the cycle setting timer T once, a new step S
_The timer operation is started in ₁₆ , S ₁₉ , S ₂₂ , and S ₂₅ , and again in steps S ₁₇ , S ₂₀ , S ₂₃ , and S ₂₆ , the wattages W ₁ , W ₂ , which gradually increase in accordance with the increase of the elapsed time, W _3, W ₄ sterilizing lamp 21a outputs the oN signal of said sterilizing lamp 21a the respective output W ₁ in accordance with the respective elapsed time,
In _{W 2, W 3, W 4} , and it turns the respective t ₁ hour (constant).

On the other hand, the above steps S ₁₁ , S ₁₂ , S ₁₃ ,
When it is determined that the sterilization lamp lighting cycle T has not elapsed in each determination in S _14, the process proceeds to step S ₂₇ without turning on the sterilization lamp 21a.

[0107] In the step S _27, the germicidal lamp 21a
Insulation switch is OF regardless of ON or OFF of
After determining whether or not the F operation has been performed, the heat insulation switch is turned on.
When NO is not performed, the intermittent lighting control of the sterilization lamp 21a with the lighting output according to the elapsed time is continued to sterilize the rice with ultraviolet rays to prevent spoilage.

On the other hand, the heat insulation switch is turned off and YE
When S is reached, all the above heat retention and sterilization control are completed.

As a result, the heat retention time is the maximum elapsed time 1
After 8 hours, the intermittent sterilization control at the _fourth lighting output W ₄ having the largest lighting output value is continued and effective under the heat-retention state centering on the target set heat-retention temperature of 70 ° C. The rice is kept warm.

As described above, in the heat retention control of the present embodiment, when the rice cooking process is completed and the heat retention process is started, the heat retention time count timer ta is started, and then the transition to the set heat retention temperature of 70 ° C. is performed. As shown in FIG. 17, first, intermittent lighting control of the sterilization lamp 21a with the _first lighting output W ₁ is started, and thereafter, the elapsed time from the start of the heat retention step ta = less than 6 hours, 6 hours ~ Less than 12 hours,
By controlling the lighting by sequentially increasing the lighting output for 12 hours to less than 18 hours and 18 hours or more, the rice is sterilized and deodorized according to the degree of progress of decay due to ultraviolet rays and ozone generated by the ultraviolet rays. . Therefore, as a result, the sterilization function improves as the heat retention time increases even if heat retention is performed at a low temperature of, for example, about 70 ° C. or less, so that the rice is less likely to rot and a good quality rice is provided for a long time. You can

(Embodiment 7) Next, FIG. 18 and FIG.
Is a configuration and an operation of the sterilization control device at the time of heat retention of the food heat insulating container according to the seventh embodiment of the present invention applied to the electric rice cooker as in the above-described first, second, third, fourth, fifth and sixth embodiments. Is shown.

For example, in the configuration of the sterilization control device of the first embodiment, even if the lid unit 2 is opened and rice is cooked while the temperature is kept warm, the sterilization lamp 21a is kept warm during the warming time. The lighting is always performed at a constant lighting cycle T. However, in practice, once the lid unit 2 is opened and rice is picked up, various bacteria are likely to invade, so that the spoilage is more likely to occur. Therefore, in the present embodiment, on the other hand, for example, as shown in the time chart of FIG. 19, after the shift to the heat retention step, the sterilization lamp 21a is operated as described above as the rice temperature decreases to the set heat retention temperature. Form 1
While intermittently controlling the lighting in the same constant lighting cycle as in the case of, when the lid unit 2 is once opened and then closed again, they are detected and the output is updated to surely sterilize, It is characterized by preventing the decay of rice due to invasion of various bacteria.

That is, as shown in FIG. 19, when the rice cooking process is completed and the warming process is started, first, in step S ₁ of the flowchart of FIG. 18, the warming lamp is turned on to display that it is in the warming state.

Then, in step S ₂ , it is determined whether or not the temperature of the inner pot 3 has fallen to a preset heat retention temperature of 70 ° C. or lower for performing intermittent lighting control of the sterilization lamp 21a.

As a result, when the temperature of the inner pot 3 which is determined to be NO has not dropped to the set heat retention temperature of 70 ° C. or lower, or when it has once dropped but rises above the same temperature of 70 ° C., step S Turn off the above heat insulation heater SH in ₃
While promoting the decrease of the inner pot temperature, step S
_{When the} lid heater FH has a duty ratio of 7/14 (14
7 seconds) to turn on the heat sink 13 to evaporate the soup (condensed droplets) generated on the back surface of the heat sink 13 of the lid unit 2 as the temperature drops to 70 ° C. To prevent white blur.

Then, in a succeeding step S ₇ , the lid unit 2
If it is not determined that the opening is performed, the process proceeds to step S ₁₁ and the same constant period T _A as in the case of the first embodiment described above.
The lighting control of the sterilization lamp 21a is executed. On the other hand, when it is detected that the lid unit 2 is opened by turning off the reed switch 18, the sterilization lamp 21a is turned off first, and then the lid unit 2 is turned on again in step S _9.
Is closed.

As a result, if YES, the following step S ₁₀
Then, the lighting output duty ratio of the sterilization lamp 21a is set to 2
The sterilization lamp 21a is turned on by setting the doubled value Wwax to perform sufficient sterilization. Then, after that, the intermittent sterilizing lamp lighting control in the normal lighting output duty ratio and the lighting cycle in step S ₁₁ is continued.

As a result, in the construction of the apparatus, even if the lid unit 2 is opened during the heat retention and rice is stuck, the decay due to the rice is suppressed to the minimum.

(Embodiment 8) FIG. 20 shows a power supply opening / closing means of a sterilization lamp lighting circuit and an opening / closing detection means of a lid unit in the electric rice cooker of the above-mentioned Embodiment 1 formed by a reed switch 18 and a magnet 17, for example. The structure of the food heat insulation container which concerns on Embodiment 8 of this invention formed of the limit switch 29 is shown.

The limit switch 29 is installed on the upper surface side of the shoulder member 5 of the outer case 1, and the upper end side thereof is O-shaped.
A push rod 29a for N, OFF operation is provided so as to be able to move up and down. The push rod 29a is always urged upward by a coil spring, for example, and is biased to turn off the opening / closing contact portion.

On the other hand, on the outer peripheral portion of the inner cover 11 of the lid unit 2 on the front end side, the push rod 29a is turned ON when the lid unit 2 is closed as shown in the figure, corresponding to the push rod 29a of the limit switch 29. The operating piece 11a that presses into a state is integrally formed.

Therefore, the limit switch 29 is
Turns ON when the lid unit 2 is closed, and turns OFF when the lid unit 2 is opened upward. Therefore, insert the opening / closing contact portion instead of the reed switch 15 in FIG. If placed, the power supply circuit of the sterilization lamp lighting circuit can be opened / closed in accordance with the opening / closing of the lid unit 2, just like the reed switch 15 described above, and the open / closed state of the lid unit 2 can be detected from the ON / OFF state. .

(Ninth Embodiment) FIG. 21 shows the configuration of an electric rice cooker which is a food heat insulating container according to a ninth embodiment of the present invention.

In the electric rice cooker, an ozone generator is provided instead of the sterilizing lamp 21a described above as a sterilizing means.

This ozone generator is constructed by providing a pair of discharge electrodes 51, 52 at the tip of a housing 50 having a built-in discharge circuit, and in the case of the first embodiment described above through a flange-shaped packing 53. Similarly to the above, it is attached to the central portion of the heat dissipation plate 13 on the back side of the lid unit 2.

Ozone (O ₃ ) has a high sterilizing power equal to or higher than the above-mentioned ultraviolet rays. Therefore, the discharge electrodes 51, 5
When the electric discharge is performed so as to generate an appropriate amount of ozone in 2, the sterilizing function exactly the same as that of the sterilizing lamp 21a can be exhibited. In particular, in the case of the sterilization lamp 21a, when the amount of rice is large, there is a drawback that ultraviolet rays do not reach the bottom portion, but in the case of ozone, since it has high permeability, an effective sterilization action should be exerted on the bottom portion. You can

The discharge cycle and discharge level can be controlled by using the same control sequence as that in each of the above-described first to seventh embodiments.

[Brief description of drawings]

FIG. 1 is a cross-sectional view of a main body of an electric rice cooker according to a first embodiment of the present invention.

FIG. 2 is an overall system circuit diagram of the electric rice cooker.

FIG. 3 is a control circuit diagram of a sterilization control device section of the electric rice cooker.

FIG. 4 is a flowchart showing sterilization control contents of the sterilization control device for the electric rice cooker.

FIG. 5 is a time chart corresponding to the sterilization control of FIG.

FIG. 6 is a control circuit diagram of a sterilization control device section of an electric rice cooker according to a second embodiment of the present invention.

FIG. 7 is a flowchart showing sterilization control contents of the sterilization control device for the electric rice cooker.

FIG. 8 is a time chart corresponding to the sterilization control of FIG.

FIG. 9 is a control circuit diagram of a sterilization control device unit of an electric rice cooker according to a third embodiment of the present invention.

FIG. 10 is a flowchart showing sterilization control contents of the sterilization control device for the electric rice cooker.

11 is a time chart corresponding to the sterilization control of FIG.

FIG. 12 is a flowchart showing sterilization control contents of the sterilization control device for an electric rice cooker according to Embodiment 4 of the present invention.

FIG. 13 is a time chart corresponding to the sterilization control of FIG.

FIG. 14 is a flowchart showing sterilization control contents of the sterilization control device for an electric rice cooker according to the fifth embodiment of the present invention.

FIG. 15 is a time chart corresponding to the sterilization control of FIG.

FIG. 16 is a flowchart showing the sterilization control content of the sterilization control device for an electric rice cooker according to Embodiment 5 of the present invention.

FIG. 17 is a time chart corresponding to the sterilization control of FIG.

FIG. 18 is a flowchart showing the sterilization control content of the sterilization control device for an electric rice cooker according to Embodiment 7 of the present invention.

19 is a time chart corresponding to the sterilization control of FIG.

FIG. 20 is an enlarged cross-sectional view of the main parts of the electric rice cooker body according to the eighth embodiment of the present invention.

FIG. 21 is a sectional view of an electric rice cooker body according to a ninth embodiment of the present invention.

[Explanation of symbols]

17 is a magnet, 18 is a reed switch, 21a is a germicidal lamp, 25 is a microcomputer control unit, 61 is a germicidal lamp lighting circuit, 65 is an oscillation circuit, 69 is an oscillation cycle setting means, 70 is an oscillation cycle varying means, and 72 is an oscillation output. It is a variable means.

Claims (13)

[Claims] 1. A food heat-insulating container comprising an inner pan for containing food, a lid for covering an opening of the inner pan, and a heat retaining means for heating and retaining the inner pot, wherein the inner pot and the lid are provided. A heat insulation container for food, comprising a sterilizing means for sterilizing the heat insulation space formed by the. 2. The food heat insulating container according to claim 1, wherein the sterilizing means is provided on the back side of the lid. 3. The food heat insulating container according to claim 1 or 2, wherein the sterilizing means is a sterilizing lamp that emits ultraviolet rays by electric discharge. 4. The sterilizing means comprises an ozone generator that generates ozone by electric discharge.
Or the food heat insulating container according to 2. 5. The intermittent drive control means for intermittently driving the sterilizing means at a constant cycle is provided.
The food heat insulating container according to 2, 3, or 4. 6. The sterilizing means is provided with an intermittent drive control means for intermittently driving the sterilizing means in a shorter cycle when the heat retaining temperature is lower than when the heat retaining temperature is high, in response to a change in the heat retaining temperature. The food heat insulating container according to 1, 2, 3 or 4. 7. The intermittent drive control means for intermittently driving the sterilizing means in a shorter cycle when the heat retention time is longer than that when the heat retention time is short according to the elapsed heat retention time. The food heat insulating container according to 1, 2, 3 or 4. 8. An intermittent drive control means for intermittently driving the sterilizing means with a constant output is provided.
The food heat insulating container according to 2, 3, or 4. 9. The sterilizing means is provided with an intermittent drive control means for intermittently driving the sterilizing means with a higher output when the heat retaining temperature is lower than that when the heat retaining temperature is high, in accordance with a change in the heat retaining temperature. , 2, 3 or 4 food heat insulation container. 10. The intermittent drive control means for intermittently driving the sterilizing means with a higher output when the heat retention time is longer than that when the heat retention time is short, according to the lapse of the heat retention time. , 2, 3 or 4 food heat insulation container. 11. A lid opening / closing detecting means for detecting the open / closed state of the lid is provided, and the driving of the sterilizing means is stopped when the lid is opened, and is driven when the lid is closed. Claims 1, 2, 3, 4, 5, 6, 7,
The food heat insulating container according to 8, 9, or 10. 12. The food heat insulation container according to claim 11, wherein the drive output of the sterilizing means started when the lid is closed is set to a higher output than the drive output in the steady state. 13. An electric rice cooker, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11
Alternatively, the food heat insulating container according to item 12.