JP2643845B2 - Electric rice cooker - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electric rice cooker capable of always maintaining a good heat retaining state of rice.

[0002]

2. Description of the Related Art In many electric rice cookers currently used, the temperature is kept at a constant set temperature of about 72 to 74 ° C. This is because rice is discolored if the temperature is too high. The temperature is set to a value that is halfway between the two, because it becomes harder, and if the temperature is too low, it gives off odor.

[0003] In the case of an electric rice cooker currently in use, a heating heater is turned on at the same time as the completion of rice cooking to start the heating.

[0004]

However, the temperature of rice at the end of cooking rice is so high that it does not need to be kept warm.
Rot is unlikely to occur, and it is necessary to keep warm after a predetermined time has elapsed.

[0005] By the way, the lower the heat retention temperature, the better the heat retention state of the rice. If the heat retention temperature is maintained for a long time, the rice rots, and if the heat retention temperature is high, the rice hardly rots, but the browning increases. Difficulty exists.

Therefore, the temperature of the rice is so high that it is not necessary to maintain the temperature. The heater is not turned on immediately after the completion of the cooking, but is turned on when the temperature of the rice is lowered to the extent that the temperature is required. The inventors of the present invention have focused on the fact that if the heat retention temperature is set higher as the heat retention time elapses, power consumption can be saved and the heat retention state can be maintained extremely well.

The present invention has been made in view of the above points, and has as its object to improve the heat retaining state of rice while saving power consumption.

[0008]

The electric rice cooker according to the present invention has a temperature detecting means for detecting the temperature of the rice cooker, and controls the power supply to the rice cooking heater and the heat retaining heater based on the temperature information from the temperature detecting means. In the electric rice cooker configured to perform the setting, the heating temperature is changed from a temperature lower than the normal heating temperature to a higher temperature in accordance with the elapse of the warming time after the completion of the rice cooking, and the setting temperature changing means. There is provided an energization control means for controlling energization to the heat retention heater so that the temperature of the rice cooker becomes the set heat retention temperature changed and set by the heat retention temperature change means.

The electric rice cooker of the present invention has the following preferred embodiments.

In other words, the setting of the set heat-retention temperature by the set heat-retention temperature changing means is set so as to increase stepwise as the predetermined heat-retention time elapses. This is preferable in that the set temperature can be changed and set while the number is reduced.

[0011] Further, the change setting of the set warming temperature by the set warming temperature changing means is performed so as to increase in proportion to the elapse of the warming time, in that the change setting of the set warming temperature can be finely performed. preferable.

[0012] Further, the change of the set heat-retention temperature by the set heat-retention temperature changing means is performed so as to increase by a predetermined value after a predetermined time has elapsed after the completion of the rice cooking. This is preferable because it can be reduced.

It is preferable to set an upper limit value to the set heat-retention temperature changed and set by the set heat-retention temperature changing means, since the heat-retention temperature can be prevented from becoming too high.

[0014] In addition, when the meal time after the start of the heat insulation is set and the meal time is set by the heat insulation timer switch, the set heat insulation temperature is changed by the set heat insulation temperature changing means after the set time elapses. It is possible to keep the rice at a high temperature in accordance with the meal time by adding a command means for instructing to change the set warming temperature to the upper limit value (in other words, the hot rice is automatically heated). Is obtained from the viewpoint of

[0015] In addition, when the heat insulation switch is turned on, the fixed heat insulation temperature setting means for setting the set heat insulation temperature to a constant value regardless of the elapse of the heat insulation time is added to provide a good heat insulation state when only the heat insulation is performed. It is preferable in that it is obtained.

In addition, it is preferable to provide a selection means for selecting a change setting of the set heat insulation temperature by the set heat insulation temperature change means and a fixed setting of the set heat insulation temperature by the fixed heat insulation temperature setting means. This is preferable because the state can be appropriately selected.

It is preferable to give priority to the fixed setting of the set warming temperature by the fixed warming temperature setting means when the cancel switch is turned ON or when the rice cooker is reset. Is preferred in that

Further, it is preferable to provide an alarm means for alerting the user when the warming time exceeds a predetermined time, since the user can be warned of deterioration of the rice due to the warming for a long time.

[0019]

According to the electric rice cooker of the present invention, the following effects can be obtained by the above means.

That is, according to the elapse of the heat retention time after the completion of rice cooking, the set heat retention temperature is changed and set so as to increase from a temperature lower than the normal heat retention temperature, and thus the rice cooker temperature becomes the changed and set heat retention temperature. By controlling the energization of the warming heater as described above, if the set warming temperature at the end of rice cooking (that is, the warming start time) is set low, the time from the end of rice cooking until the rice cooker temperature falls to the set warming temperature is set. The heat retention heater can be turned off, and the heat retention temperature can be gradually increased as the heat retention time elapses. That is, when there is no possibility of putrefaction immediately after cooking rice, the temperature is kept at a low temperature at which a good heat-retaining state can be obtained, and when the keeping time is long and there is a risk of putrefaction, the temperature can be kept at a high temperature.

In the preferred embodiment of the electric rice cooker according to the present invention, the following effects can be obtained.

In other words, if the setting of the set heat-retaining temperature by the set heat-retaining temperature changing means is set so as to increase stepwise as the fixed heat-retaining time elapses, the setting man-hour for changing the set heat-retaining temperature is reduced. The change of the set temperature can be performed while reducing the number.

Further, if the setting of the set heat retaining temperature by the set heat retaining temperature changing means is set so as to increase in proportion to the elapse of the heat keeping time, the change setting of the set heat retaining temperature is changed to the elapse of the heat keeping time. It can be done finely according to the texture.

[0024] Further, when the setting of the set heat-retaining temperature by the set heat-retaining temperature changing means is set to be higher by a predetermined value after a lapse of a predetermined time after the completion of the cooking of rice, the setting man-hour for changing the set heat-retaining temperature is reduced. Can be less.

Further, when an upper limit value is set for the set heat retention temperature changed and set by the set heat retention temperature changing means, it is possible to prevent the heat retention temperature from becoming too high and the rice from being altered (in other words, browned). it can.

In addition, when the meal time after the start of the heat insulation is set and the meal time is set by the heat insulation timer switch, the set heat insulation temperature is changed by the set heat insulation temperature changing means after the set time elapses. In the case where a command means for instructing the user to change the set warming temperature to be the upper limit value is provided, the rice can be warmed to a high temperature state in accordance with the meal time (in other words,
Hot rice is automatically obtained).

[0027] Further, when a fixed heat-retaining temperature setting means for setting the set heat-retaining temperature to a constant value regardless of the elapse of the heat-retaining time is provided when the heat-retaining switch is turned on, a good heat-retaining state is obtained when only the heat-retaining is performed. can get.

In the case where a selection means for selecting a change setting of the set heat insulation temperature by the set heat insulation temperature changing means and a fixed setting of the set heat insulation temperature by the fixed heat insulation temperature setting means is provided, two heat insulation means are provided by the user's will. The state can be appropriately selected.

When the fixed temperature setting by the fixed temperature setting means is prioritized when the cancel switch is turned on or when the rice cooker is reset, various usage patterns of the user (that is, when the rice cooker is reset). Good thermal insulation (ie, when a normal use form is not taken) (ie,
Insulation by the insulation control based on the fixed set insulation temperature) is obtained.

If an alarm is provided to warn the user when the heat retention time exceeds a predetermined time, the user is warned of the deterioration of the rice (in other words, the occurrence of browning) due to the heat retention for a long time. be able to.

[0031]

According to the electric rice cooker of the present invention, the set temperature changing means for changing and setting the set heat retaining temperature from the temperature lower than the normal heat retaining temperature to the temperature according to the elapse of the heat retaining time after the completion of the rice cooking. Power supply control means for controlling power supply to the warming heater so that the rice cooker temperature becomes the set warming temperature changed and set by the set temperature determining means,
In accordance with the elapse of the heat retention time from the end of rice cooking, the set heat retention temperature is changed and set so that it rises from a temperature lower than the normal heat retention temperature, and then to the heat retention heater so that the rice cooker temperature becomes the changed set heat retention temperature. Since the energization of the rice is controlled, if the set warming temperature at the end of rice cooking (that is, the time of starting warming) is set low, the warming heater is not operated until the rice cooker temperature drops to the set warming temperature from the end of rice cooking. In addition to being able to be in the OFF state, it is possible to gradually increase the heat retention temperature as the heat retention time elapses. When there is a danger, it can be kept at a high temperature), which saves power consumption and keeps rice warm, which is less likely to rot and brown. There is.

[0032]

Preferred embodiments of the present invention will be described below with reference to the accompanying drawings.

First Embodiment FIGS. 1 to 3 show an electric rice cooker according to a first embodiment of the present invention.

As shown in FIG. 1, the electric rice cooker according to the present embodiment has both a function of cooking rice and a function of keeping heat, and has a bottomed cylindrical shape in which a rice cooker 6 can be set. Container body 1 and a lid unit 7 for covering the upper part of the container body 1
And is constituted by.

The container body 1 includes a cylindrical outer case 2 formed of a thin metal plate, and a synthetic resin shoulder member 4 and a bottom member 3 respectively connected to upper and lower ends of the outer case 2.
The inside of which is provided with a bottomed cylindrical inner container 5 for setting the rice cooker 6 so as to be able to be taken out.

At the center of the bottom surface of the inner container 5, there is provided a center sensor 28 which is in contact with the bottom surface of the rice cooker 6, and an annular rice cooker H is provided so as to surround the center sensor 28.
₁ is buried in the hot platen 24. In the center sensor 28, a temperature sensing element (described later) that acts as a temperature detecting means for detecting the temperature of the rice cooker 6
And a rice set sensor (described later) for detecting whether or not the rice 6 is set.

The lid unit 7 has a hollow structure with an outer cover 8 made of synthetic resin forming an outer peripheral surface and an inner cover 9 made of synthetic resin forming an inner peripheral surface. The inner cover 9 is joined to the inner cover 9 with good airtightness by high frequency welding or the like. The lid unit 7 is rotatably attached to one side of the shoulder member 4 via a hinge mechanism 20, and has an open end engaged with a predetermined position of the lid unit A lock mechanism 21 for maintaining the closed state of the unit 7 is provided.

At a substantially central portion of the lid unit 7,
A steam discharge port 15 is provided, and a steam discharge cylinder mounting hole 13 is formed below the steam discharge port 15. In the vapor discharge cylinder mounting hole 13, a rubber vapor discharge cylinder packing 14 is mounted.

Further, below the lid unit 7, an inner lid 10 for closing the upper opening of the rice cooker 6 is provided, and at the center of the inner lid 10, the inner lid 10 is provided. A steam discharge cylinder 12 having a built-in pressure regulator 11 for allowing steam guided to an internal space 16 above the inner lid 10 to escape to the outside via a steam port 17 formed at an appropriate position is fixed. The steam discharge tube 12 is detachably attached to the steam discharge tube packing 14. That is, the inner lid 10 is detachably attached to the lid unit 7 via the vapor discharge tube 12. The space between the lid unit 7 and the inner lid 10 is sealed by a packing 18 attached to a peripheral portion of the inner cover 9 to prevent steam from leaking to the outside from portions other than the pressure regulator 11. ing.

A heat retaining heater H ₂ is disposed on the outer peripheral side of the inner container 5, and a shoulder heater H ₃ is disposed at a portion of the shoulder member 4 to which the inner lid 10 is joined. Heat retaining heater H ₂ is used to prevent spoilage primarily kept warm rice after cooking, the shoulder heater H ₃ is the inner cover 10 to evaporate the water droplets produced on the surface thereof is heated by thermal conduction, It is used to prevent water drops from falling into the rice cooker 6.

On the other hand, between the outer case 2 and the inner container 5, a rice cooking heater H ₁ , a warming heater H ₂ and a shoulder heater H _{3 are provided.}
A microcomputer 23 for controlling power supply to the power supply is accommodated. The shoulder member 4 is provided with an operation board 22 constituting an operation section.

As shown in FIG. 2, the operation board 22 has a menu switch for selecting four rice cooking functions (white rice cooking menu), that is, white rice cooking, quick cooking rice, cooking rice cooking, and rice cooking rice. 31, a reheating switch 32 operated at the time of reheating, and an operation performed at the time of starting the heat retention and at the time of canceling various operations (that is, the temperature retention is started by one ON operation, and by another ON operation, Various operations are canceled.) Heating / cancellation switch 33, rice cook start switch 34 for starting rice cooker, reservation switch 35 for timer reservation of rice cook start time, and lighted when the rice cook start switch 34 is turned on. Rice cooker indicator light 3 that indicates that it is in a cooked rice state
6 and a heat-retention indicator light 3 which is lit when the heat-retention / cancel switch 33 is turned ON once to indicate that the apparatus is in a heat-retention state.
7, a reservation indicator light 38 illuminated when the reservation switch 35 is turned on to indicate that it is in a reserved state, a reheat indicator light 40 illuminated when the reheat switch is turned on to indicate a reheat state, A liquid crystal display section 39 for displaying the type of the rice cooking menu selected by the menu switch 31 and visually recognizing the user;
, A time switch 50 operated at the time setting, a minute switch 51 operated at the time setting, and a warming timer switch 56 for setting a meal time after the warming is started.
And a heat retention timer switch indicator light 57 that is turned on when the heat retention timer switch 56 is activated.

The liquid crystal display 39 displays a liquid crystal display (hereinafter, referred to as "rice cooked rice"), "cooked rice cooked", "rice cooked rice", or "rice cooked rice" when the menu switch 31 is selected. (Abbreviated as LCD) 41 to 44 are provided. In this embodiment, the menu switch 3
Every time 1 is inserted, the loops of the LCDs 41 to 44 for "white rice cooking", "fast-cooking rice", "cooking rice", and "okowa rice cooking" are sequentially selected. The liquid crystal display 39 also displays a clock.

Next, the configuration of the electric control unit in the electric rice cooker of this embodiment will be described with reference to the electric circuit diagram shown in FIG. In FIG. 3, components corresponding to the components shown in FIGS. 1 and 2 are denoted by the same reference numerals.

In FIG. 3, reference numeral 48 denotes a commercial AC power supply. Electric power from the commercial AC power supply 48 is supplied to the rice cooking heater H ₁ , the heat retaining heater H _2, and the shoulder heater H _3. Power is also supplied as power. Reference numeral 52 denotes a temperature sensing element (for example, a thermistor) which is built in the center sensor 28 and serves as a temperature detecting means for detecting the temperature of the rice cooker 6, and 53 denotes a rice for detecting whether or not the rice cooker 6 is set. The unit set sensor, 54 is a temperature fuse, and 55 is a timer for counting the elapsed time after the start of heat retention.

The microcomputer 23 operates according to a predetermined program based on a clock signal from a reference frequency generating circuit (not shown), and as shown in FIG.
The set warming temperature changing means 231 changes and sets the set warming temperature from a temperature lower than the normal warming temperature to a higher temperature according to the elapse of the warming time from the end of rice cooking. and energization control means 232 for controlling the energization of the set retained temperature in rice device temperature becomes so insulation heater H _2, insulation / cancellation once during the oN operation of the switch 33 (i.e., kept at the start) of the incubation time in Fixed warming temperature setting means 233 for setting the warming temperature to a constant value irrespective of progress, alarm means 234 for warning the user when the warming time exceeds a predetermined time, and meal time by the warming timer switch 56 At the time of the setting, the setting heat-retention temperature changing means 231 is changed so that the set heat-retention temperature becomes the upper limit value after the lapse of the set time. It is configured by a command means 235 commands the occupied performed.

The setting change of the set warming temperature by the set warming temperature changing means 231 starts at the time t immediately after the end of the rice cooking.
Until ₁ (for example, 8 hours) elapses, the set temperature T which is lower than the normal heat retaining temperature (for example, about 72 ° C.)
s ₁ (for example, 65 ° C.), a set temperature Ts ₂ (for example, 68 ° C.) immediately after the completion of rice cooking until a time t ₂ (for example, 12 hours) elapses, and a time t ₃ (for example, immediately after rice cooking is completed)
Until 16 hours have elapsed, the set temperature Ts ₃ (for example,
After the time t ₃ elapses immediately after the completion of the rice cooking, the temperature is set in a stepwise manner according to the elapse of a constant heat retention time such as a set temperature Ts ₄ (for example, 74 ° C.).

Further, the set heat-retaining temperature set by the fixed heat-retaining temperature setting means 233 is the above-mentioned maximum set heat-retaining temperature Ts ₄ .

Further, the warning by the warning means 234 is performed by blinking the heat-retention indicator 37. In this embodiment, after the heat-retention time t _{3 has} elapsed, the heat-retention indicator 37 is turned on for the first blinking interval Δ.
It blinks at t ₁ (for example, at 1 second intervals), and after the elapse of the heat retention time t ₄ (for example, 20 hours), the heat retention indicator 37 is turned on at a second blinking interval Δt ₂ (for example, shorter than the first blinking interval Δt ₁₎ .
This is performed by blinking at 0.5 second intervals).

Further, the instructing means 235 makes the heat keeping elapsed time t ₁ , t ₂ , t ₃ correspond to the reservation setting time ts by the heat keeping timer switch 56 to the set heat keeping temperature changing means 231 to t ₁ ′. , T ₂ ′, t ₃ ′. For example, when ts = 8 hours, t
₁ '= 4 hours, t _2' = 2 hours, and t ₃ '= 2 hours.

Next, the contents of the heat retention control by the microcomputer 23 will be described with reference to the flowcharts shown in FIGS.

[0052] As shown in FIG. 5, a determination is made cooking start switch 34 at step S ₁ is a whether or not turned ON, the cooking indicator 36 in step S ₂ in the case where an affirmative determination is lit and cooking heaters is cooking is performed by H _1, is one of determining whether cooking completion is made in step S _3. In the case where a negative determination is made in step S _1, the heat insulating switch 3 in step S ₄
It is determined whether or not No. 3 has been turned on. If the determination is affirmative, the heat retention control is performed based on the set heat retention temperature Ts ₄ = 73 ° C. fixedly set by the fixed heat retention temperature setting means 233 described later. Incidentally, if a negative determination is made in step S ₄ returns to step S _1.

[0053] If an affirmative determination is made in step S _3, since a state at the same time kept warm cooking is finished is started, kept indicator in step S ₅ 37
Lights up. Then, thermal insulation timer switch 56 in step S ₆ is made whether the determination has been turned ON, an affirmative determination (i.e., heated timer switch 56 → O
In the case of N), the process proceeds to step S _7, if reservation setting mealtime (in other words, the time set) is made, step S
As described above in FIG. ₈ , the heat retention elapsed times t ₁ , t ₂ , and t ₃ are changed according to a command from the command means 235 to t ₁ ′, t ₂ ′, and t ₃ ′.
After being replaced in, the process proceeds to step S _9, step S ₆
Determination is negative (i.e., heated timer switch 56 → OFF) in the case of directly proceeds to step S _9, the count of the timer 55 is started.

Subsequently, in steps S ₁₀ to S ₁₃ , the elapse of the heat retention time t is monitored by the timer 55,
Step If it is determined that t <t ₁ = 8 h at S ₁₃ (at the time of ON warmth timer switch 56, t
<The t ₁ '), the center sensor 2 in step S ₁₄
The temperature information T from the temperature sensing element 52 of _No. 8 is input, and in step S15, the temperature is compared with the set warming temperature Ts ₁ = 65 ° C. While T> Ts ₁ = 65 ° C., step S ₁₅ is performed. insulation heater H ₂ at ₁₆ is turned OFF. Then, T ≦ Ts ₁ = 65 ℃ in step S ₁₅
Insulation heater H ₂ in it is determined step S ₁₇ is turned ON, kept is executed with. In other words, immediately after the rice cooking, until the heat retention time t ₁ (the heat retention time t ₁ ′ when the heat retention timer switch 56 is ON) elapses, the heat retention is controlled by the set heat retention temperature Ts ₁ = 65 ° C. never kept heater H ₂ is turned oN, the
Rice device temperature than is so that the ON / OFF by heat keeping control of insulation heater H ₂ is made after decreased to set retained temperature Ts ₁ = 65 ℃ (see Figure 7).

[0055] In the ON time of step t ≧ t ₁ = 8 h at S ₁₃ (thermal insulation timer switch 56, t ≧
If it is determined that t ₁ '), the temperature information T from the temperature sensing element 52 of the center sensor 28 is inputted in step S _18, then the settings retained temperature T in step S ₁₉
A comparison is made with s ₂ = 68 ° C., and while T ≦ Ts ₂ = 68 ° C., the heater H ₂ is turned on in step S ₁₇ .
If it is determined that T> Ts ₂ = 68 ° C. in step S ₁₉ , the heater H ₂ is turned off in step S ₁₆ .
The heat retention control performed at F is executed. The above control (at the time of ON warmth timer switch _{56, t ≧ t 2 ')} t ≧ t 2 = 12 hours in the step S ₁₂ is performed until it is determined. In other words, immediately after cooking rice, the warming time t
₁ (After the heat retention time t ₁ ′ when the heat retention timer switch 56 is ON), the heat retention time t ₂ = 12 hours (until the heat retention time t ₂ ′ when the heat retention timer switch 56 is ON). Is controlled to be kept at the set temperature Ts ₂ = 68 ° C. (see FIG. 7).

[0056] In the ON time of step t ≧ t ₂ = 12 hours in S ₁₂ (insulation timer switch 56, t ≧
If it is determined t ₂ ') and the temperature information T from the temperature sensing element 52 of the center sensor 28 is inputted in step S _20, then the settings retained temperature T in step S ₂₁
The comparison is made with s ₃ = 71 ° C., and while T ≦ Ts ₃ = 71 ° C., the heat retention heater H ₂ is turned on in step S ₁₇ .
If it is determined that T> Ts ₃ = 71 ° C. in step S ₂₁ , the heater H ₂ is turned off in step S ₁₆ .
The heat retention control performed at F is executed. The above control (at the time of ON warmth timer switch _{56, t ≧ t 3 ')} t ≧ t 3 = 16 h in step S ₁₁ is performed until it is determined. In other words, immediately after cooking rice, the warming time t
₂ (After the heat retention time t ₂ ′ when the heat retention timer switch 56 is ON), the heat retention time t ₃ = 16 hours (until the heat retention time t ₂ ′ when the heat retention timer switch 56 is ON) Is controlled by the set temperature Ts ₃ = 71 ° C. (see FIG. 7).

[0057] In the ON time of step t ≧ t ₃ = 16 hours in S ₁₁ (insulation timer switch 56, t ≧
If it is determined that t ₃ '), a warning by the warning means 234 in step S ₂₂ (i.e., blinking at the first blink Delta] t ₁ warmth indicator 37) is made, step S ₂₃
Temperature information T from the temperature sensing element 52 of the center sensor 28 is inputted, the comparison between the set retained temperature Ts ₄ = 74 ° C. at that time in step S ₂₄ is made in, T ≦ Ts ₄ = 7
While the temperature is 4 ° C., the heat retention heater H ₂ is turned on in step S ₁₇ , and T> Ts ₄ = 74 in step S ₂₄ .
℃ If it is determined that kept the heater H ₂ in step S ₁₆
Is turned off, the heat retention control is executed. The above control is continued thereafter. In other words, immediately after cooking rice, the warming time t
_{After the} elapse of ₃ = 16 hours (when the heat retention timer switch 56 is ON, the heat retention time t ₃ ′) has elapsed, the heat retention is controlled at the set heat retention temperature Ts ₄ = 74 ° C. (see FIG. 7).

[0058] If it is determined that t ≧ t ₄ = 20 hours in step S _10, a warning by the warning means 234 in step S _{2 5} (i.e., flashing at the second blink Delta] t ₂ warmth indicator 37 ) is made, the process proceeds to a subsequent step S _23, the subsequent processing is performed.

[0059] Thereafter, when the cancel switch 33 is turned ON in step S _26, the timer 55 is reset in step S _27, insulation indicator 37 in step S ₂₈ is returned to be off the initial mode. In addition, until the cancel switch 33 is turned ON in step S ₂₆ heat keeping control described above is continued.

By the way, (in other words, if the thermal insulation switch 33 has been turned ON) if the determination is positive at step S _4, the as shown in FIG. 6, insulation indicator 37 in step S ₂₉ is turned on begins the count of the timer 55 in step S _30, after the temperature information T from the temperature sensing element 52 of the center sensor 28 is inputted in step S _31, is fixedly set by fixing retained temperature setting means 233 in the step S ₃₂ Set insulation temperature Ts
₅ = 73 ° C. Comparison with is made, T <Ts ₅ = 73 While a ° C. is kept heater H ₂ is ON in step S ₃₃
Is, heated heater H ₂ is OFF in step S ₃₄ if it is determined that T ≧ Ts ₅ = 73 ℃ in step S ₃₂
Is performed. That is, immediately after the rice cooking, the heat retention is controlled at the fixed set heat retention temperature Ts ₅ = 73 ° C. regardless of the heat retention time (see FIG. 7). In ongoing such warmth control, the course of incubation time t in step S ₃₅ and step S ₃₆ is monitored, when it is determined that t ≧ t ₃ = 16 h in step S _36, in step S ₃₇ A warning is issued by the warning means 234 (that is, the warming indicator 37 blinks at the first blinking interval Δt ₁ ), and if it is determined in step S ₃₅ that t ≧ t ₄ = 20 hours, then in step S ₃₈ A warning is issued by the warning means 234 (that is, the warming indicator 37 blinks at the second blinking interval Δt ₂ ). Step S
(In other words, if not long insulation) When a negative determination is made in ₃₆ to return to step S _29.

[0061] Thereafter, when the cancel switch 33 is turned ON in step S _39, the timer 55 is reset in step S _40, insulation indicator 37 in step S ₄₁ is returned to be off the initial mode. Note that until the cancel switch 33 is turned ON in step S ₃₉ is kept controlled by the fixed settings retained temperature Ts ₅ described above is continued.

As described above, according to the present embodiment, the set warming temperature T is set in accordance with the lapse of the warming time t from the end of rice cooking.
s is changed set to be higher than normal retained temperature, thus for the energization of the thermal insulation heater H ₂ as rice device temperature T is has to be controlled to the set thermal insulation was changed set temperature Ts ₁ ~Ts ₄ , cooking end time (i.e., heated starting point) is set retained temperature Ts ₁ to set low the, and the OFF state kept the heater H ₂ until rice device temperature T from cooking end time falls to set retained temperature Ts ₁ In addition, the temperature can be gradually increased as the heat retention time t elapses (when there is no risk of putrefaction immediately after cooking, the temperature is kept at a low temperature where a good heat retention state is obtained, and the heat retention time t becomes longer and putrefaction may occur. In some cases, the temperature can be maintained at a high temperature), so that the power consumption can be saved, and the rice can be kept hard to rot and hardly cause browning.

Further, the change setting of the set warming temperature Ts is performed stepwise (ie, after a lapse of four hours) after the initial warming time has elapsed (t ₁ or t ₁ ′), according to the lapse of the constant warming time t (ie, the lapse of 4 hours). (In 3 ° C. increments), it is possible to perform the change setting of the set heat retention temperature Ts while reducing the number of process steps for changing the set heat retention temperature Ts.

Further, by setting the upper limit value Ts ₄ = 74 ° C. to the set heat-retention temperature Ts to be changed and set, the heat-retention temperature becomes too high and the rice is degraded (in other words, browned). Can be prevented.

When the heat-insulating switch 33 is turned ON, the heat-insulating temperature is set to a constant value T regardless of the elapse of the heat-insulating time t.
By setting s ₅ = 73 ° C., it is possible to obtain a good heat-retaining state (a heat-retaining state in which rot is prevented and browning does not occur) when only heat-retention is performed.

When the warming timer switch 56 is turned on (that is, when a meal time reservation is set), the set warming temperature Ts is changed to the upper limit value T after the reservation setting time has elapsed.
By that as set retained temperature so as to s ₄ is changed settings, meal time can be obtained rice sizzling automatically.

In addition, the heat retention time t is equal to the predetermined time t ₃ = 16
When the time and t ₄ = 20 hours or more, the user can be alerted to a two-stage warning of the deterioration of rice (in other words, the occurrence of browning) due to the long-term heat retention, thereby making it possible to appeal to avoid the long-time heat retention. .

Embodiment 2 In the case of this embodiment, the point that the set temperature Ts by the set temperature changing means 231 is set to be changed to be proportionally higher and the point that the one-hour timer is used as the timer 55 is implemented. The other configuration is the same as that of the first embodiment except for the difference from the first embodiment, so that the description is omitted to avoid duplication.

Next, with reference to a flow chart shown in FIG. 8, the heat retention control by the microcomputer in the electric rice cooker according to the second embodiment will be described in detail.

[0070] cooking start switch 34 at step S ₁ is whether the determination is ON is made, rice indicator 36 in step S ₂ in the case where an affirmative determination is executed rice according to and cooking heater H ₁ lit. , is one of determining whether cooking completion is made in step S _3. Incidentally, if a negative determination is made in step S _1, insulation switch 33 in step S ₄ is made a determination whether or not turned ON, the fixed set by fixing retained temperature setting means 233 to be described later when a positive determination is made Insulation control is performed with the set insulation temperature Ts ₄ = 73 ° C. Incidentally, if a negative determination is made in step S ₄ returns to step S _1.

[0071] Then, insulation indicator 37 in Step S ₅ is lit when the determination is positive at step S _3, kept timer switch 5 in step S ₆
6 is made whether the determination has been turned ON, and set to [Delta] T = 0.5 in step S ₇ in the case of a negative determination, mealtime reservation setting in step S ₈ when a positive determination is made ( In other words, the time set) is made,
Step value is determined by the difference ts of [Delta] T between the reservation start time and reservation time in S ₉ ΔT '[e.g., [Delta] T' =
0.5 × (16 / ts)}. Where ΔT
Indicates a coefficient for calculating a temperature coefficient β (described later) when the set warming temperature is changed and set.

Next, the timer 55 in step S ₁₀
Counting is started, counting up of the timer 55 in step S ₁₁ ~ step S ₁₄ (step S ₁₁₎
(In other words, 1 hour at every elapse) every timer 55 is reset (Step S _12), the rewriting of the time factor α operation (step S ₁₃₎ and the temperature coefficient beta (step S ₁₄₎
Is performed. That is, α is set to α: α + 1 every hour, and β = ΔT × α (β = ΔT ′ × α when the heat retention timer switch 56 is ON). Here, α is an integer of 0 to 15.

[0073] Then, the timer 5 in step S ₁₁
If 5 is determined not to be counted up (that is, if the hour is determined not to have elapsed), the temperature information T from the temperature sensing element 52 of the center sensor 28 in step S ₁₅ is inputted, the comparison of the setting retained temperature Ts = 65 + β ℃ at that time in step S ₁₆ is performed, while a T> Ts is kept heater H ₂ at step S ₁₇ is turned OFF. And step S
Insulation heater H ₂ in step S ₁₈ if it is determined that T ≦ Ts in ₁₆ is turned ON, kept is executed. That, rice device temperature T up to 1 hour immediately after cooking completion has elapsed is incubated heater H ₂ is ON at the time when decreased to 65 ° C., then to rice device temperature T is set retained temperature Ts = 65 ° C. After two hours have passed since the end of the rice cooking, the set temperature Ts is increased by ΔT ° C every hour.
= 0.5 ° C. (ΔT ′ ° C. when the heat-retention timer switch 56 is ON), and the heat-retention control is continued such that the rice cooker temperature T becomes the set heat-retention temperature Ts at that time. . In the case of the present embodiment, the upper limit value Tsmax of the set warming temperature Ts is α = 16, β = 16Δ
The temperature becomes 73 ° C., which is T, and thereafter, the temperature is controlled to be maintained at the set temperature of 73 ° C.

[0074] On the other hand, (in other words, if the thermal insulation switch 33 has been turned ON) if the determination is positive at step S _4, the insulation indicator 37 is turned in the step S _19, in step S ₂₀ beta = after being re-set to 8, the process returns to step S _15, a similar warmth and control described above is executed, setting retained temperature Ts at this time 65 + 8
= 73 ° C.

[0075] The duration of the heat keeping control as described above, accumulation operation of the holding time t in step S ₂₁ is performed, the passage of incubation time t is monitored at step S ₂₂ and step S _23, t in step S ₂₃ If it is determined that ≧ t ₅ = 15 hours, a warning by the warning means at step S ₂₄ (i.e., blinking at the first blink Delta] t ₁ warmth indicator 37) is made, t ≧ t ₆ at step S ₂₂ (= 2
If it is determined 0 hours) and a warning by the warning means at step S ₂₅ (i.e., flashing at the second blink Delta] t ₂ warmth indicator 37) is made.

[0076] Thereafter, when the cancel switch 33 is turned ON in step S _26, alpha in step S _27,
β is reset, the timer 55 in step S ₂₈
There is reset, incubated indicator 37 in Step S ₂₉
Turns off and returns to the initial mode. Incidentally, cancel switch 33 is in until it is turned ON kept controlled as described above is continued in step S ₂₆ (see FIG. 9).

As described above, according to the present embodiment, the change of the set warming temperature Ts is changed according to the lapse of the constant warming time t (ie, 1 hour) (ie, 0.5 ° C. or ΔC).
T ′ ° C.), the setting of the set heat retaining temperature Ts can be changed almost proportionally as the heat retaining time t elapses as shown in FIG. Insulation control can be performed by changing the insulation temperature. It should be noted that if the interval of the heat retention time t is reduced and the interval of the temperature is decreased, the change of the set thermal insulation temperature Ts can be performed more proportionally. Other functions and effects are the same as those of the first embodiment, so that the description is omitted to avoid duplication.

Embodiment 3 This embodiment is different from Embodiment 1 in that, when the reservation is set by the heat retention timer switch 56, the set heat retention temperature is changed from a time that is a predetermined time before the reservation setting time. Only the other configuration is the same as that of the first embodiment, and the description is omitted to avoid duplication.

Next, with reference to the flow charts shown in FIGS. 10 to 12, the heat retention control by the microcomputer in the electric rice cooker according to the third embodiment will be described in detail.

[0080] As shown in FIG. 10, a determination is made cooking start switch 34 at step S ₁ is a whether or not turned ON, the cooking indicator 36 in step S ₂ in the case where an affirmative determination is lit and cooking heaters is cooking is performed by H _1, is one of determining whether cooking completion is made in step S _3. Incidentally, if a negative determination is made in step S _1, it is determined whether insulation switch 33 is ON in step S ₄ is made, whether or not the "normal kept" in step S _5, if a positive determination is made Is determined, and the affirmative determination is made (that is, in the case of “normal heat retention”), the heat retention control is performed with the set heat retention temperature Ts ₄ = 73 ° C. fixed by the fixed heat retention temperature setting means 233 described later (FIG. 11). Step S
Returns to step S ₁ in the case of a negative determination is made in _4.

[0081] When a negative determination is made in the case and step S ₅ an affirmative determination is made in step S _3, a time ON operation state and insulation switch 33 cooking is completed by thermal insulation at the same time is started Because it is not in the “normal heat insulation” state (ie, in the “low temperature insulation” state)
Insulation indicator 37 is turned on in step S _6. Here, the “low temperature keeping” refers to heat keeping control that changes the set warming temperature Ts from a low temperature to a high temperature as the warming time t elapses. Then, thermal insulation timer switch 56 in step S ₇ is whether the determination has been turned ON is made, affirmative (i.e., heated timer switch 56 → ON) in the case of the insulation control described later is performed (see FIG. 12 ), the determination is negative determination in step S ₇ (i.e., when the thermal insulation timer switch 56 → OFF), the process proceeds to step S _8,
The timer 55 starts counting.

Subsequently, in steps S ₉ to S ₁₂ , the elapse of the heat retention time t is monitored by the timer 55,
Step If it is determined that t <t ₁ = 8 h at S _12, the step temperature information T from the temperature sensing element 52 of the center sensor 28 in S ₁₃ is input, then the settings retained temperature Ts in step S ₁₄ comparison with ₁ = 65 ° C. is performed, while a T> Ts ₁ = 65 ℃ heat insulating heater H ₂ at step S ₁₅ is turned OFF. The insulation heater H ₂ in step S ₁₆ if it is determined that T ≦ Ts ₁ = 65 ℃ in step S ₁₄ is turned ON, kept is executed. In other words, the temperature is controlled to be maintained at the set temperature Ts ₁ = 65 ° C. immediately after the rice is cooked until the temperature retention time t ₁ elapses. Immediately after the rice is cooked, the temperature control heater H ₂ is not turned on, and the rice cooker temperature is maintained. O warmth heater H ₂ after but was lowered to set retained temperature Ts ₁ = 65 ° C.
The heat retention control by N / OFF is performed (see FIG. 7).

[0083] If it is determined that t ≧ t ₁ = 8 h in step S _12, the temperature information T from the temperature sensing element 52 of the center sensor 28 is inputted in step S _17, set at that time in step S ₁₈ Insulation temperature Ts ₂ = 68
And T ≦ Ts ₂ = 68 ° C., the heater H ₂ is turned on in step S ₁₆ ,
In step _{S 18 T> Ts 2 = 68} ℃ and it is determined incubated controlled insulation heater H ₂ is OFF in step S ₁₅ is executed. The above control is performed in step S
_{The process} is performed until it is determined in step ₁₁ that t ≧ t ₂ = 12 hours. In other words, immediately after the rice is cooked, the set temperature T is maintained until the time t ₂ = 12 hours elapses after the time t ₁ elapses.
Insulation control is performed at s ₂ = 68 ° C. (see FIG. 7).

If it is determined in step S ₁₁ that t ≧ t ₂ = 12 hours, temperature information T from the temperature sensing element 52 of the center sensor 28 is input in step S ₁₉ ,
Step Setting retained temperature at that time in S ₂₀ Ts ₃ = 7
A comparison with 1 ° C. is made, and while T ≦ Ts ₃ = 71 ° C., the heat retention heater H ₂ is turned on in step S ₁₆ , and if it is determined in step S ₂₀ that T> Ts ₃ = 71 ° C., the step is performed. heat keeping control of insulation heater H ₂ in S ₁₅ is OFF is performed. The above control is performed in step S ₁₀ until it is determined that t ≧ t ₃ = 16 hours. That is, the heat insulation control is performed at the set heat insulation temperature Ts ₃ = 71 ° C. after the heat insulation time t ₂ elapses immediately after the rice cooking until the heat insulation time t ₃ = 16 hours elapse (see FIG. 7).

[0085] If it is determined that t ≧ t ₃ = 16 h in step S _10, a warning by the warning means 234 in step S ₂₁ (i.e., blinking at the first blink Delta] t ₁ warmth indicator 37) is made, the temperature information T is input from the temperature sensing element 52 of the center sensor 28 in step S _22, then the settings retained temperature T in step S ₂₃
Comparison is made with s ₄ = 74 ° C., and while T ≦ Ts ₄ = 74 ° C., in step S ₁₈ , the heat retention heater H ₂ is
If it is determined that T> Ts ₄ = 74 ° C. in step S ₂₃ , the heater H ₂ is turned off in step S ₁₅ .
The heat retention control performed at F is executed. The above control is continued thereafter. In other words, immediately after cooking rice, the warming time t ₃ = 1
After the elapse of 6 hours, the heat retention is controlled at the set heat retention temperature Ts ₄ = 74 ° C. (see FIG. 7).

If it is determined at step S ₉ that t ≧ t ₄ = 20 hours, then at step S ₂₄ the alarm means 2
34 WARNING (i.e., flashing at the second blink Delta] t ₂ warmth indicator 37) is made, then the process proceeds to step S _22, the subsequent processing is performed. Then, step S ₂₅
In the cancel switch 33 is turned ON, the timer 55 is reset in step S _26, insulation indicator 37 in step S ₂₇ is returned to off by an initial mode. Note that the above-described heat retention control is continued until the cancel switch 33 is turned ON in step _S254 .

[0087] Incidentally, (in other words, when the "normal warmth") If the determination is positive at step S _5, the
As shown in FIG. 11, insulation indicator 37 is turned in the step S _28, the count of the timer 55 is started in step S _29, the temperature information T is input from the temperature sensing element 52 of the center sensor 28 in step S ₃₀ after being fixed retained temperature setting means 233 in the step S ₃₁
Is compared with the set warming temperature Ts ₅ = 73 ° C., and while T <Ts ₅ = 73 ° C., the warming heater H ₂ is turned on in step S ₃₂ , and T ≧ T in step S ₃₃ . When it is determined that Ts ₅ = 73 ° C., the heat retention control for turning off the heat retention heater H ₂ is executed in step S ₃₇ . That is, immediately after the rice cooking, the heat retention is controlled at the fixed set heat retention temperature Ts ₅ = 73 ° C. regardless of the heat retention time. In ongoing such warmth control, the course of incubation time t is monitored at step S ₃₄ and step S _35, t ≧ t ₃ in step S ₃₅ =
If it is determined that 16 hours, warning by the warning means 234 in step S ₃₆ (i.e., blinking at the first blink Delta] t ₁ warmth indicator 37) is made, step S ₃₄
If it is determined that t ≧ t ₄ = 20 hours in the warning by the warning means 234 in step S ₃₇ (i.e.,
The heat-retention indicator 37 flashes at the second flashing interval Δt ₂ ). Incidentally, (in other words, if not long insulation) When a negative determination is made in step S ₃₅ to return to step S _28.

[0088] Thereafter, when the cancel switch 33 is turned ON in step S _38, the timer 55 is reset in step S _39, insulation indicator 37 in step S ₄₀ is returned to be off the initial mode. Incidentally, heat keeping control while the previously described in the step S ₃₈ to cancel switch 33 is turned ON (i.e., normally kept control based on the fixed set retained temperature Ts ₅₎ is continued.

[0089] On the other hand, in other words when (the determination is positive at step S _7, incubated timer switch 56 is ON
If) which is operated, as shown in FIG. 12, the process proceeds to step S _41, if the reservation setting (i.e. mealtimes, time set) is performed, the course of 20 seconds in the step S ₄₂ is confirmed. The elapse of the time is provided to confirm completion of the time setting. Then, the difference between the reservation setting time tm and the current time tn in step S ₄₃ is monitored and the difference therebetween is the predetermined time ta = 30 minutes (i.e.,
tm-tn ≦ ta), after the temperature information T from the temperature sensing element 52 of the center sensor 28 is inputted in step S _44, the maximum setting retained temperature Ta = 73 in step S ₄₅
The temperature is compared with the temperature, and while T ≦ Ta = 73 ° C., the heat retention heater H ₂ is turned on in step S _{46. If} it is determined in step S ₄₅ that T> Ta = 73 ° C., the process proceeds to step S ₄₇ . runs heat keeping control of insulation heater H ₂ is OFF is (in other words, tm-tn> for ta) when a negative determination is made in step S _43, the temperature sensing element of the center sensor 28 in step S ₄₈ after the temperature information T from 52 is input, compared with the low-temperature setting retained temperature Tb = 65 ° C. is performed in step S _49, T ≦
While a Tb = 65 ° C. The insulation heater H ₂ at step S ₅₀ is turned ON, in step S ₄₉ T> T
heat keeping control of b = 65 ° C. and it is determined in step S ₅₁ is kept heater H ₂ is OFF is performed. That is, when the reservation setting of the meal time is made, the heat retention control at the low temperature setting heat retention temperature Tb = 65 ° C. is executed until the predetermined time ta = 30 minutes before the reservation setting time tm, and the predetermined time is set from the reservation setting time tm. From the time ta = 30 minutes before, the heat retention control at the maximum set heat retention temperature Ta is executed (see FIG. 13).

[0090] Thereafter, when the cancel switch 33 is turned ON in step S _52, the "normal kept" memory in step S _53, the process returns to step S ₂₆ (see FIG. 10), above the same processing is performed You. On the other hand, if a negative determination is made in step S ₅₂ (i.e., if the cancel switch 33 has not been turned ON), the process proceeds to step S _54, whether rice unit 6 is set determination is made,
If an affirmative determination is made (i.e., if the rice unit 6 is set) to return to step S _43, thereafter the foregoing and similar processing is performed. When a negative determination is made in step _S54 (that is, when the rice cooker 6 is not set), the process proceeds to step _S55 , and it is determined whether two seconds have elapsed. if the state of rice device 6 is not set it continues for more than 2 seconds) to return to step S _53,
“Normal heat retention” is stored. Incidentally, the flow returns to step S ₄₃ when a negative determination is made in step S _55.

As described above, according to the present embodiment, when the reservation setting of the meal time is made, the low temperature setting temperature Tb = 65 ° C. until the predetermined time ta = 30 minutes before the reservation setting time tm. Since the heat retention control at the maximum set heat retention temperature Ta is to be executed for a predetermined time ta = 30 minutes before the reservation set time tm, the maximum set temperature is set at the reservation set time tm. Hot rice warmed at the warming temperature Ta can be obtained.

In the case of the present embodiment, the cancel switch 33
At the time of ON operation or resetting of the rice cooker 6,
Has become the "normal insulation" is made to the priority, diverse use of a user (i.e., if the normal use mode is not taken) good thermal insulation corresponding to (i.e., the fixed setting retained temperature Ts ₅ (Thermal insulation by the thermal insulation control based on the above).

The other functions and effects are the same as those of the first embodiment, and the description is omitted to avoid duplication.

Fourth Embodiment FIGS. 14 to 18 show a configuration and a flowchart of an operation board, an electric circuit, and a microcomputer in an electric rice cooker according to a fourth embodiment of the present invention.

In the case of the present embodiment, the heat insulation / cancel switch 33 set in the first embodiment is set independently of the heat insulation switch 33 and the cancel switch 58, and the heat insulation temperature set by the set heat insulation temperature changing means 231. Ts
And a selection switch 59 acting as a selection means for selecting a fixed setting of the set warming temperature Ts by the fixed warming temperature setting means 233. Reference numeral 60 denotes a selection switch indicator light that is turned on when the selection switch 59 is operated. The other configuration is the same as that of the first embodiment, and the description is omitted to avoid duplication.

Next, the heat retention control by the microcomputer in this embodiment will be described in detail with reference to the flowcharts shown in FIGS.

In the case of the present embodiment, the set temperature maintaining temperature changing means 2
A change setting (hereinafter, referred to as “low heat insulation”) of the set heat retention temperature Ts by 31 and a fixed setting of the set heat retention temperature Ts by the fixed heat retention temperature setting means 233 (hereinafter, “normal heat insulation”) are selected. It is, as shown in FIG. 17, leave the memory "normal insulation" in step S _1, O step S ₂ ~ step cooking switch 34 in S _4, insulation switch 33 and select switch 59
Confirm N operation. The selection switch 59 is turned on without the rice cook switch 34 and the heat retention switch being turned on.
When operated, the "normal warmth" for determining whether or not made at step S _5, when a positive determination step S
Proceed to ₆ are replaced is the memory "normal insulation" is the "cold insulation" in step S _1, when a negative determination (i.e., if already the "cold insulation") is
In step S ₇ "cold insulation" is replaced with "normal warmth". This process is performed to select “low temperature insulation” or “normal insulation” according to the user's will.

[0098] When the rice switch 34 is turned ON, rice indicator 36 is executed cooking by and cooking heaters H ₁ is turned on in step S _8, step S ₉
It is determined whether cooking is finished or not. Then, if the determination is positive at step S _9, since a state in which cooking is completed by thermal insulation at the same time has been started, kept indicator 37 in step S ₁₀ is turned on. Then
Insulation timer switch 56 is ON in Step S ₁₁
It is engineered for determining whether or not made, in the case of affirmative determination (i.e., heated timer switch 56 → ON), the process proceeds to step S _12, (in other words, the time set) reservation setting mealtimes is made, step warm elapsed time in S ₁₃ t
₁ , t ₂ , t ₃ are t ₁ ′,
After being replaced with t ₂ ′ and t ₃ ′, the process proceeds to step S _{14. If} the determination in step S ₁₁ is a negative determination (that is, the warming timer switch 56 → OFF), the process directly proceeds to step S ₁₄ and the timer 55 The count starts.

[0099] Subsequently, elapse of the holding time t by the timer 55 is monitored at step S ₁₅ ~ step S _18,
Step If it is determined that t <t ₁ = 8 hours in S _18, step temperature information T from the temperature sensing element 52 of the center sensor 28 in S ₁₉ is input, set retained temperature at that time in step S ₂₀ Ts comparison with ₁ = 65 ° C. is performed, while a T> Ts ₁ = 65 ℃ heat insulating heater H ₂ at step S ₂₁ is turned OFF. The insulation heater H ₂ in step S ₂₂ if it is determined that T ≦ Ts ₁ = 65 ℃ in step S ₂₀ is turned ON, kept is executed. In other words, the temperature is controlled to be maintained at the set temperature Ts ₁ = 65 ° C. immediately after the rice is cooked until the temperature retention time t ₁ elapses. Immediately after the rice is cooked, the temperature control heater H ₂ is not turned on, and the rice cooker temperature is maintained. O warmth heater H ₂ after but was lowered to set retained temperature Ts ₁ = 65 ° C.
The heat retention control by N / OFF is performed (see FIG. 7).

[0100] If it is determined that t ≧ t ₁ = 8 h in step S _18, the temperature information T from the temperature sensing element 52 of the center sensor 28 is inputted in step S _23, set at that time in step S ₂₄ Insulation temperature Ts ₂ = 68
C., and while T ≦ Ts ₂ = 68 ° C., the heat retention heater H ₂ is turned on in step S ₂₂ ,
Heat keeping control of insulation heater H ₂ in step S ₂₁ if it is determined that T> Ts ₂ = 68 ℃ in step S ₂₃ is OFF is performed. The above control is performed in step S
_{The process} is performed until it is determined at ₁₇ that t ≧ t ₂ = 12 hours. In other words, immediately after the rice is cooked, the set temperature T is maintained until the time t ₂ = 12 hours elapses after the time t ₁ elapses.
Insulation control is performed at s ₂ = 68 ° C. (see FIG. 7).

If it is determined in step S ₁₇ that t ≧ t ₂ = 12 hours, temperature information T from the temperature sensing element 52 of the center sensor 28 is input in step S ₂₅ ,
Step Setting retained temperature at that time in S ₂₆ Ts ₃ = 7
Comparison with 1 ℃ is made, while a T ≦ Ts ₃ = 71 ℃ heat insulating heater H ₂ at step S ₂₂ is turned ON, if it is determined that T> Ts ₃ = 71 ℃ in step S ₂₆ Step heat keeping control of insulation heater H ₂ is OFF in S ₂₁ is executed. The above control is performed until it is determined that t ≧ t ₃ = 16 h in step S _16. That is, the heat insulation control is performed at the set heat insulation temperature Ts ₃ = 71 ° C. after the heat insulation time t ₂ elapses immediately after the rice cooking until the heat insulation time t ₃ = 16 hours elapse (see FIG. 7).

If it is determined in step S ₁₆ that t ≧ t ₃ = 16 hours, a warning is issued by the warning means 234 in step S ₂₇ (that is, the heat retaining indicator 37 blinks at the first blinking interval Δt ₁ ). is made, the temperature information T is input from the temperature sensing element 52 of the center sensor 28 in step S _28, then the settings retained temperature T in step S ₂₉
Comparison is made with s ₄ = 74 ° C., and while T ≦ Ts ₄ = 74 ° C., the heat retention heater H ₂ is turned on in step S ₂₂ .
If it is determined that T> Ts ₄ = 74 ° C. in step S ₂₉ , the heater H ₂ is turned off in step S ₂₁ .
The heat retention control performed at F is executed. The above control is continued thereafter. In other words, immediately after cooking rice, the warming time t ₃ = 1
After the elapse of 6 hours, the heat retention is controlled at the set heat retention temperature Ts ₄ = 74 ° C. (see FIG. 7).

If it is determined in step S ₁₇ that t ≧ t ₄ = 20 hours, a warning is issued by the warning means 234 in step S ₃₀ (that is, the warming indicator 37 blinks at the second blink interval Δt ₂ ). is made, the process proceeds to a subsequent step S _28, the subsequent processing is performed.

[0104] Thereafter, when the cancel switch 33 is turned ON in step S _31, the timer 55 is reset in step S _32, insulation indicator 37 is turned off in step S ₃₃ and returns to the initial mode. In addition, until the cancel switch 33 is turned ON in step S ₃₁ heat keeping control described above is continued.

[0105] Incidentally, (in other words, if the thermal insulation switch 33 has been turned ON) if the determination is positive at step S ₃ proceeds to step S _34, a determination is made whether the "normal warmth", a negative determination (In other words,
If “low temperature insulation” is specified), step S ₁₀
Returning to FIG. 17, the same processing as described above is performed thereafter.

[0106] On the other hand, (in other words, if the "normal insulation" is specified) If the determination is positive in step S ₃₄ to, as shown in FIG. 18, the process proceeds to step S _35, insulation indicator 37 is turned on, the count of the timer 55 is started in step S _36, the temperature information T from the temperature sensing element 52 of the center sensor 28 in step S ₃₇
After There inputted, set retained temperature Ts ₅ fixed set by the fixed heat retaining temperature setting means 233 in the step S ₃₈
= Comparison with 73 ° C. is performed, T <incubated heater H ₂ in step S ₃₉ while they become Ts ₅ = 73 ° C. is ON
Is, heated heater H ₂ is OFF at T ≧ Ts ₅ = 73 ℃ it is determined in step S ₄₀ in step S ₃₈
Is performed. That is, immediately after the rice cooking, the heat retention is controlled at the fixed set heat retention temperature Ts ₅ = 73 ° C. regardless of the heat retention time. In ongoing such warmth control, the course of incubation time t in step S ₄₁ and step S ₄₂ is monitored, when it is determined that t ≧ t ₃ = 16 h in step S _42, the step S
_{At 43} , a warning is issued by the warning means 234 (that is, the heat keeping indicator 37 blinks at the first blinking interval Δt ₁ ). If it is determined at step _S41 that t ≧ t ₄ = 20 hours, then step S is performed. _{At 44} , a warning is issued by the warning means 234 (that is, the warming indicator 37 blinks at the second blinking interval Δt ₂ ). Incidentally, (in other words, if not long insulation) When a negative determination is made in step S ₄₂ to return to step S _35.

[0107] Thereafter, when the cancel switch 33 is turned ON in step S _45, the "normal kept" memory in step S _46, the process returns to step S ₃₂ (see FIG. 17), above the same processing is performed You. On the other hand, if a negative determination is made in step S ₄₅ (i.e., if the cancel switch 33 has not been turned ON), the process proceeds to step S _47, whether rice unit 6 is set determination is made,
If an affirmative determination is made (i.e., if the rice unit 6 is set) to return to step S _37, thereafter the foregoing and similar processing is performed. If a negative determination is made in step S ₄₇ (i.e., if the rice device 6 is not set), the process proceeds to step S _48, the whether or not after two seconds determination is made, if an affirmative determination (i.e., if the state of rice device 6 is not set it continues for more than 2 seconds) to return to step S _46,
“Normal heat retention” is stored. Incidentally, the flow returns to step S ₃₇ when a negative determination is made in step S _48.

In the case of this embodiment, the selection switch 59 is turned on by the user's will to appropriately select “selective heat retention” by the set heat retention temperature changing means 231 and “normal heat retention” by the fixed heat retention temperature setting means 233. You can do it.

In the case of this embodiment, the cancel switch 33
At the time of ON operation or resetting of the rice cooker 6,
Has become the "normal insulation" is made to the priority, diverse use of a user (i.e., if the normal use mode is not taken) good thermal insulation corresponding to (i.e., the fixed setting retained temperature Ts ₅ (Thermal insulation by the thermal insulation control based on the above).

The other functions and effects are the same as those of the first embodiment, and the description is omitted to avoid duplication.

The present invention is not limited to the configuration of each of the above-described embodiments, and it is needless to say that the design can be changed as appropriate without departing from the gist of the invention.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view of an electric rice cooker according to a first embodiment of the present invention.

FIG. 2 is an enlarged plan view showing a control board unit in the electric rice cooker according to the first embodiment of the present invention.

FIG. 3 is an electric circuit diagram showing a control circuit unit in the electric rice cooker according to the first embodiment of the present invention.

FIG. 4 is a block diagram showing the contents of a microcomputer in the electric rice cooker according to the first embodiment of the present invention.

FIG. 5 is a main routine of a flowchart showing heat retention control in the electric rice cooker according to the first embodiment of the present invention.

FIG. 6 is a subroutine of a flowchart showing heat retention control in the electric rice cooker according to the first embodiment of the present invention.

FIG. 7 is a characteristic diagram showing changes in rice cooking characteristics and a set warming temperature in the electric rice cooker according to the first embodiment of the present invention.

FIG. 8 is a flowchart illustrating heat retention control in the electric rice cooker according to the second embodiment of the present invention.

FIG. 9 is a characteristic diagram showing changes in rice cooking characteristics and a set warming temperature in the electric rice cooker according to the second embodiment of the present invention.

FIG. 10 is a main routine of a flowchart showing heat retention control in the electric rice cooker according to the third embodiment of the present invention.

FIG. 11 is one subroutine of a flowchart showing heat retention control in the electric rice cooker according to the third embodiment of the present invention.

FIG. 12 is another subroutine of a flowchart showing heat retention control in the electric rice cooker according to the third embodiment of the present invention.

FIG. 13 is a characteristic diagram showing changes in rice cooking characteristics and a set warming temperature in the electric rice cooker according to the third embodiment of the present invention.

FIG. 14 is an enlarged plan view showing a control board unit in the electric rice cooker according to the fourth embodiment of the present invention.

FIG. 15 is an electric circuit diagram showing a control circuit unit in the electric rice cooker according to the fourth embodiment of the present invention.

FIG. 16 is a block diagram showing the contents of a microcomputer in the electric rice cooker according to the fourth embodiment of the present invention.

FIG. 17 is a main routine of a flowchart showing heat retention control in the electric rice cooker according to the fourth embodiment of the present invention.

FIG. 18 is a flowchart illustrating a subroutine for controlling heat retention in the electric rice cooker according to the fourth embodiment of the present invention.

[Explanation of symbols]

22 is an operation board, 23 is a microcomputer, 28 is a center sensor, 33 is a warming / cancelling switch, 34 is a rice cooker start switch, 37 is a warming indicator light, 39 is a liquid crystal display, 52 is a thermosensitive element, 55 is a timer, 56 is a heat retention timer switch, 59 is a selection switch, 231 is a set temperature change means, 232 is a conduction control means, 233 is a fixed heat retention temperature setting means, 234 is an alarm means, 235 is a command means, H
₁ rice cooking heater, H ₂ is kept warm heater.

Claims (10)

(57) [Claims] 1. An electric rice cooker comprising a temperature detecting means for detecting a temperature of a rice cooker, wherein the electric rice cooker is configured to control energization of a rice cooker and a warming heater based on temperature information from the temperature detector. Depending on the elapse of the warming time since the end of rice cooking, the set warming temperature may be lower than the normal warming temperature.
Setting heat retaining temperature changing means for changing and setting so as to be higher , and energizing control means for controlling energization to the heat retaining heater so that the rice cooker temperature becomes the set heat retaining temperature changed and set by the setting heat retaining temperature changing means. An electric rice cooker comprising: 2. The method according to claim 1, wherein the setting of the set heat-retention temperature by the set heat-retention temperature changing means is performed so as to increase stepwise as a predetermined heat-retention time elapses. The electric rice cooker according to 1. 3. The apparatus according to claim 1, wherein the setting of the set heat retaining temperature by the set heat retaining temperature changing means is performed so as to increase in proportion to the elapse of the heat retaining time. Electric rice cooker. 4. A temperature control device according to claim 2, wherein
The setting for changing the temperature is set after a predetermined time has passed since the end of rice cooking.
It must be performed so as to increase by a predetermined value.
2. The electric rice cooker according to claim 1, wherein: 5. The electric rice according to any one claim of the claims 1 to 4, characterized in that it is set the upper limit value in setting retained temperature is changed and set by said setting retained temperature changing means vessel. 6. A heat-retention timer switch for making a reservation setting of a meal time after the start of heat-retention, and at the time of setting the meal time by the heat-retention timer switch, the set heat-retention temperature is set to the set heat-retention temperature changing means after the set time elapses. 6. The electric rice cooker according to claim 5 , further comprising command means for instructing to change and set the set warming temperature so as to reach the upper limit value. Wherein said preceding claims, characterized in that the thermal insulation switch has attached the fixed heat retaining temperature setting means for setting a constant value set retained temperature regardless elapse of the holding time in a case where it is ON 6 An electric rice cooker according to any one of the preceding claims. Wherein said claims, characterized in that annexed selection means for selecting a fixed Configuring retained temperature by the set retained temperature changing means according to settings retained temperature change settings and the fixed heat retaining temperature setter 7 An electric rice cooker as described. 9. Fixed Setting retained temperature by the fixed heat retaining temperature setting means, claim 7 and claim 8, characterized in that it is prioritized at the time of or during meal instrument resetting ON operation of the cancel switch An electric rice cooker according to any one of the preceding claims. 10. The electric rice cooker according to any one of claims 1 to 9 , further comprising alarm means for alerting a user when the heat retention time exceeds a predetermined time.