JPH105126A - Rice cooker having warming function - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve heat insulating property and prevent the eating quality from being deteriorated by selecting a course between a warming course which is combinedly formed from a high temperature for a specific value or more and a low temperature less than the specific value, and a warming course mainly for a high temperature of the specific value or more. SOLUTION: A warming selection switch 99 for switching a fresh warming course and a high warming course is so formed as to alternately switch on either of the both warming courses at every time of being pressed. A warming means 104 is started by pressing on a warming switch 98 and controls heating by a side heater and a lid heater so as to hold the temperature in the pot detected by a pot temperature sensor 23 at a prescribed temperature. The fresh warming course warms the content in combination of the high temperature of 68 deg.C or more and the low temperature between 60 deg.C or more and less than 68 deg.C. The high temperature course warms it to mainly high temperature of 68 deg.C or more. The switching operation of the warming courses can be selected before starting the cooking, before starting the reserved cooking, before starting the warming, and during warming. This constitution can facilitate the selection and the setting of the warming course.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to a rice cooker with a heat retaining function.

[0002]

2. Description of the Related Art Conventionally, various methods for controlling the heat retention in rice cookers with a heat retaining function have been proposed. For example, JP
Japanese Patent Application Publication No. 7-9425 discloses that, in order to prevent a decrease in flavor of rice even during long-time heat retention and to reduce power consumption, rice is not heated for, for example, three hours after cooking, or is not heated. It has been proposed to keep the temperature so as to be kept at a temperature of around 70 ° C., and thereafter to keep the rice at a temperature of around 70 ° C. Also, Japanese Patent Application Laid-Open No. 7-29898
A similar proposal is made in Japanese Patent Application Laid-Open No. 4 and JP-A-7-313354.

In addition, the heat retention temperature, which is usually 68 ° C. or higher, is temporarily lowered to a low temperature of less than 68 ° C., thereby suppressing yellowing and odor by suppressing the Maillard reaction, and suppressing the generation of heat odor due to oxidation of fatty acids. Rice cookers with a heat retention function have also been commercialized. Because this method of keeping the temperature of rice lower,
Although the heat retaining state of the rice is improved, there is a disadvantage that the taste deteriorates in terms of the temperature of the rice.

[0004] On the other hand, rice cookers with a heat-retaining function that can select between the above-mentioned low-temperature heat-retention and high-temperature heat-retention have also been commercialized. This rice cooker chooses to keep warm at a lower temperature when keeping it warm for a long time, while it chooses to keep warm at a higher temperature if you like rice with a better taste in terms of temperature. It is.

[0005] Further, the user can select a first heat insulation course for keeping heat by a combination of low temperature and high temperature and a second heat insulation course mainly for keeping heat at high temperature, and memorize the selected heat insulation course. Rice cookers with a heat retention function that prioritize the stored heat retention courses have also been commercialized. The first heat insulation course aimed at improving the heat insulation state,
In spite of the fact that it was originally developed as a heat-retention system to be mainly used, the temperature is low, so that it must be used in combination with high-temperature heat retention by the second heat-retention course in terms of taste. This is because the temperature setting in the first heat retention course is inappropriate. In addition, it is troublesome for the user to select the heat retention course, and it is difficult to make an appropriate selection.

[0006]

SUMMARY OF THE INVENTION As described above, a conventional heat insulation course in which a first heat insulation course for maintaining heat by a combination of low and high temperatures and a second heat insulation course mainly for high temperature insulation can be selected. In the rice cooker with the function, when the first heat retention course is selected, there is a problem that the taste of the rice deteriorates in terms of temperature, and if the taste of the rice is given priority, the second heat retention course has to be selected. In addition, it is necessary to appropriately select the two heat retention courses, but it is not easy for the user to select the heat retention course. This is especially true if there are restrictions on when you can choose a warming course.

[0007] The present invention is intended to solve such problems, and it is possible to improve the heat retention state, improve the taste, and perform appropriate heat retention, and select and set a heat retention course. It is an object of the present invention to provide an easy-to-use rice cooker with a heat retaining function.

[0008]

According to a first aspect of the present invention, there is provided a rice cooker having a heat retaining function, comprising a combination of a high temperature of 68 ° C or more and a low temperature of 60 ° C or more and less than 68 ° C. Heating course selection means for selecting a first heat retention course for keeping heat, and a second heat retention course for keeping heat mainly at a high temperature of 68 ° C. or more, and rice cooking means for carrying out rice cooking and keeping the temperature after the completion of rice cooking A reserved rice cooker that keeps warming after finishing rice cooking at a predetermined time or after a predetermined time; a heat keeping means that starts keeping heat from an off state; and the rice cooking means and the reserved rice cooker based on selection by the heat keeping course selecting means. Means and a control means for controlling the heat retaining means. And
Before starting the rice cooking by the rice cooking means, before starting the reserved rice cooking by the reserved rice cooking means, before starting the heat retention by the heat retaining means, and during the heat retention by the rice cooking means,
During the warming by the reserved rice cooking means and during the warming by the warming means, the warming course selecting means can select the first warming course and the second warming course.

[0009] The user can appropriately select a heat retention course before starting rice cooking, before starting reserved rice cooking, before starting heat retention, and during heat retention, depending on preference and the like. When the first heat retention course is selected, the heat retention at a lower temperature is performed, and the deterioration of the rice is small even with the heat retention for a long time. On the other hand, when the second heat retention course is selected, the heat retention at a higher temperature is performed, and the decrease in taste due to the low rice temperature is sufficiently prevented. However, even in the first heat-retention course, since the temperature is kept at a combination of a high temperature of 68 ° C. or more and a low temperature of 60 ° C. or more and less than 68 ° C., a decrease in taste due to the low temperature is prevented. Therefore, usually, only the first heat-retention course is used for appropriate heat retention, and selection of the heat-retention course is unnecessary.

A second aspect of the present invention is the rice cooker with the heat retaining function according to the first aspect of the present invention, wherein the first heat retaining course is selected after a predetermined time has elapsed from the end of the rice cooking, or If one of the heat retention courses is selected,
It does not maintain heat at a low temperature of less than 68 ° C.

[0011] If the heat retention at a low temperature is continued for a long time, the rice may be putrefied. Therefore, even after the predetermined time has elapsed from the end of rice cooking, even if it is the first heat insulation course including the heat insulation at a low temperature, the heat insulation is not performed at a low temperature of less than 68 ° C. so that the rice does not rot. I do. In addition, even after a predetermined time has elapsed from the end of rice cooking, the heat insulation course can be selected by the heat insulation course selection means, and the first heat insulation course can be selected. Is prevented.

According to a third aspect of the present invention, in the rice cooker with the warming function according to the first aspect of the present invention, when the warming is stopped and the state is turned off, or when the control means is in the initial state, The first heat retention course is set with priority, and it is displayed that the first heat retention course is set.

As described above, the first heat retaining course is set so as to obtain appropriate heat retaining properties, and is set as a normally used one. When the control unit is turned off or the control unit is set to the initial state, the setting of the heat retention course is automatically set to the first heat retention course, and the user does not need to select the first heat retention course.

[0014]

DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of a rice cooker with a heat retaining function according to the present invention will be described below with reference to the drawings. In FIG. 7, reference numeral 1 denotes a rice cooker main body, which is a bottomed cylindrical inner frame 2 having an open upper surface, and an outer frame 3 having the inner frame 2 therein and forming an outer shell of the rice cooker main body 1. And a bottom plate 4 that covers the bottom side of the outer frame 3. An annular rib-shaped pot supporting portion 5 is formed at the upper end of the inner frame 2 forming the pot accommodating portion. On the other hand, a notch 6 is formed at the upper end of the outer frame 3 at the outer periphery of the pot supporting portion 5. The lower surface of the notch 6 is an inclined surface 6a that descends outward from the pot support 5. The inner frame 2 is
It is made of FR-PET resin and has a shape substantially similar to the outer shape of the pot 11 which is removably accommodated in the inner frame 2.

The pot in which rice or water to be cooked is stored
11 is formed in a bottomed cylindrical shape with an open upper surface, and at the upper end of the outer surface of the pot 11, a flange portion 12 that projects horizontally outward is formed.
A pan handle 13 is provided so as to cover the same. In addition, hot pot 11
Is formed by a pot body 14 mainly made of an aluminum material, and a heat generating layer 15 made of a magnetic metal material provided on a curved portion from a lower side surface to a bottom surface of the pot body 14.

Reference numeral 21 denotes a heating coil provided outside the inner frame 2 and serving as heating means for causing the heating layer 15 of the pot 11 to generate heat by electromagnetic induction. The heating coil 21 is helically wound around the outer surface of the inner frame 2 so as to face the heat generating layer 15 of the pan 11, and is fixed. Outside the heating coil 21, there is provided a coil cover 22 in which a high magnetic permeability material powder mainly composed of iron oxide or the like is mixed with a plastic material. Thus, the heating coil 21 is fixed to the inner frame 2, and the heat generation layer 15 is efficiently heated by induction by preventing leakage of magnetic flux. Reference numeral 23 denotes a pot temperature sensor that includes a negative temperature coefficient thermistor inside and detects the temperature at the bottom of the pot 11,
Reference numeral 24 denotes a thermal fuse provided near the heat generating layer 15 and the heating coil 21 and provided on the outer surface of the inner frame 2. In addition, 25
Is a side heater which is a heating means for keeping heat provided on the upper side of the outer surface of the inner frame 2.

Reference numeral 26 denotes a heating board provided with an inverter circuit component 27 for supplying a predetermined high-frequency current to the heating coil 21 and the like. Then, from the inverter circuit, the heating coil 21
When a high-frequency current is supplied to the heating coil 21, an alternating magnetic field is generated in the heating coil 21, an eddy current is generated in the heating layer 15 of the pot 11 in the magnetic field, and this eddy current is converted into Joule heat. The heating layer 15 generates heat, and the pot 11 is heated. The inverter circuit is controlled by a microcomputer 91 (shown in FIG. 1) which constitutes a heating adjusting means together with the inverter circuit.
The amount of heating by 21 is adjusted. The heating substrate 26 is disposed between the bottom plate 4 at the bottom of the rice cooker main body 1 and the support 28 together with a cooling fan 30 having a motor 29 by a support 28 provided inside the rice cooker main body 1. I have. The bottom of the bottom plate 4 facing the cooling fan 30 has an air inlet
An exhaust port 32 is provided on a side surface of the bottom plate 4 facing one side of the heating substrate 26.
The support 28 is provided in an upright state on one side of the heating substrate 26, and an LC that forms an operation panel 33 as a display operation means is provided between the support 28 and the front surface of the rice cooker main body 1.
Operation unit 36 consisting of D34, LED35 and various switches
The display operation component 37 provided with
It is provided in a state of being mounted on. Reference numeral 40 denotes a code reel that winds the power cord 41 provided on the lower rear side of the outer frame 3.

Reference numeral 51 denotes a lid which covers the upper opening of the pan 11 so that it can be opened and closed. The lid body 51 is attached to the outer lid 52 while forming a space below the outer lid 52, and an outer lid cover 53 provided along the lower outer periphery of the outer lid 52. The lid lower surface plate 54 directly covers the upper opening of the pot 11 as a lid lower surface member forming the lower surface. The lid 51 is supported by a hinge shaft 55 on the upper rear side of the rice cooker main body 1. Although not shown, an elastic member such as a torsion coil spring is provided inside the hinge shaft 55 to apply a force to the cover 51 in a direction to always open. On the other hand, on the upper side of the rice cooker main body 1 or the lid 51 on the side opposite to the hinge shaft 55, the lid 51 is closed with respect to the rice cooker main body 1 against the force exerted by the elastic member. Is provided. Further, the lid body 51 is provided with a steam port 57 for discharging steam generated in the pot 11 during cooking rice to the outside of the rice cooker main body 1. Although the steam port 57 will be described in detail later, the pot 11 of the steam port 57 is positioned at the center of the cover lower plate 54 at a position substantially opposite to the center of the inner diameter of the upper opening of the pot 11.
An opening 58 having a diameter of about 70 mm forming a side portion is formed.

The cover lower plate 54 is fixed to the outer cover 53 at the outer periphery thereof. Between the cover lower plate 54 and the outer cover 53, an annular material made of an elastic material such as silicone rubber is provided. The lid packing 59 is sandwiched and fixed. When the lid 51 is closed, the lid packing 59 is in close contact with the flange portion 12 of the pan 11, and the lid lower plate 54 and the pan 11
Are sealed in a sealed state.

The lid lower plate 54 is made of an austenitic stainless steel material such as SUS304 which does not easily rust. The lid lower plate 54 has an uneven portion 61 on the surface to improve the strength by work hardening. The material thickness t of the lid lower plate 54 is
At the time of manufacturing, the concave portion of the concave-convex portion 61 is stamped and formed by press working, and then press-formed into a predetermined shape. The concave-convex portion 61 forms a concave mark on only the surface facing the pot 11 side. Lid 51 on the back side corresponding to this recess
The inner side is formed to be substantially flat or to have a protruding shape with a small protruding height that is small enough to allow the lid heater 62 composed of a cord heater as a heating means to be bonded. On the other hand, on the front side (pan 11 side) of the lid lower surface plate 54, the deeper the depth of the concave-shaped indented recess, the higher the effect of improving strength, but there is a disadvantage that the surface becomes difficult to wipe. Is preferably suppressed to about 1 mm or less. The planar shape of the concave portion is not particularly limited, and may be selected in consideration of design such as a circle, an ellipse, a triangle, and a turtle pattern. Further, after the lid lower plate 54 is formed into a predetermined shape or before pressing, it is buffed to improve the appearance by giving a metallic luster and to improve the appearance of the rice cake (hot water or water in which starch is dissolved). Should be less noticeable. In addition, in order to obtain gloss, a material processed in a state of a plate material before press molding may be used, and the uneven portion 61 is not necessarily required. Due to the luster, it is only necessary that the adhesion of the tongue is inconspicuous and that the dirt can be easily wiped off.

Further, an annular outer convex portion 63 is formed on the outer peripheral portion of the lower surface of the lid lower plate 54. The outer peripheral side of the outer peripheral convex portion 63 forms a tapered wrap portion 64 facing the inner peripheral side of the flange portion 12 of the pan 11 while holding a small gap when the lid body 51 is closed. Has become.

A lid heater 62 provided on the back surface of the lid lower plate 54 is fixed to the lid lower plate 54 by an aluminum foil 66 adhered to the lid lower plate 54 by a double-sided adhesive tape. Further, the lid heater 62 includes a heat insulating plate 67 fixed to the outer lid cover 53.
Is covered from above. And the lid heater 62
In the lid lower plate 54, they are arranged almost uniformly around the opening 58 forming the steam port 57, and are arranged near the opening 58 and near the lid packing 59. In addition,
The lid heater 62 and the side heater 25 electrically form a parallel circuit, are connected by a series circuit to a power cutoff control element such as a bidirectional thyristor, and are controlled by a predetermined energizing time to cook rice and to keep warm. The lid lower plate 54 and the inner frame 2 are each heated. The switching control element is controlled by a microcomputer 91 constituting a heating adjusting means together with the switching control element.
The heating amount of the side heater 25 is adjustable.
Further, on the back surface of the lid lower plate 54, a lid temperature sensor 68 composed of a negative characteristic thermistor for detecting the temperature of the lid lower plate 54 is provided. The lid temperature sensor 68 is pressed against the lid lower plate 54 via the aluminum foil 66 by a sensor holder 69 provided on the heat insulating plate 67.

Next, the structure of the steam port 57 will be described. A cylindrical vertical rib 71 having an open upper and lower surface is formed integrally with the outer lid 52 at a position facing the opening 58 of the lid lower plate 54 so as to extend downward. Between the lower end of this vertical rib 71 and the position around the opening 58 on the lid lower plate 54,
Steam port packing made of elastic material such as silicone rubber
It is sealed in a sealed state with 72 interposed. Also,
A vapor port cover 73 that closes the upper opening of the vertical rib 71 and forms the outer surface of the lid 51 is detachably attached to the vertical rib 71. The steam port cover 73 has a tubular portion 74 extending downward from the peripheral portion thereof and located in the vertical rib 71, and covers the opening 58 from the periphery and from above. The lower end of the cylindrical portion 74 is sealed in contact with the steam port packing 72 so as to prevent steam leakage from the surroundings. Further, a steam discharge port 75 is formed in an upper portion of the steam port cover 73. And steam port cover 73
Is formed on the outer lid 52 by hooking a claw portion 76 formed partially on the outer surface upper portion of the cylindrical portion 74 with a claw portion 77 formed on the inner peripheral side of the upper end portion of the vertical rib 71. It is attached detachably.

A steam port bucket 81 is detachably accommodated in the steam port cover 73. The steam port bucket 81 is in the shape of a bottomed container, and the bottom portion is always placed on the lid lower plate 54 to close the opening 58. When the steam port bucket 81 rises due to the pressure of the steam in the pan 11, a gap is formed between the bottom of the steam port bucket 81 and the periphery of the opening 58 of the lid lower plate 54, and the gap is formed by the steam. An intrusion hole 82 is formed. Further, a gap formed in a vertical direction between the outer surface of the steam port bucket 81 and the inner surface of the cylindrical portion 74 of the steam port cover 73 allows the steam inlet hole 82 to communicate with the steam outlet 75. The passage hole 83 is formed. The upper opening of the steam port bucket 81 has a through hole.
A partition plate 86 having 84 and a vertical wall 85 is provided.
The steam discharge port 75 is connected to a steam port bucket 81 through a through hole 84.
Facing the inner surface of the. Further, at the bottom of the steam port bucket 81, there are formed a plurality of tongue return holes 87 having a diameter of about 1 to 2 mm, and an elastic material such as silicone rubber which closes the tongue return holes 87 so as to be openable from below. A check valve 88 made of a material is provided. The diameter of the opening area of the return hole 87 is smaller than the planar opening area of the steam passage hole 83.

FIG. 1 shows a system block diagram.
Reference numeral 91 denotes a microcomputer serving as control means. The microcomputer 91 includes a rice cooker switch of the operation unit 36.
92, a clock switch 93, an hour switch 94, a minute switch 95, a reservation switch 96, an off switch 97, a heat insulation switch 98, a heat insulation selection switch 99 which is a heat insulation course selection means, a reset means 101 including a reset switch, etc., and a heat sensitive means. The pot temperature sensor 23 and the lid temperature sensor 68, the LCD 34 and the LED 35 as display means,
102, the reserved rice cooking means 103, and the heat retaining means 104 are connected. The rice cooking switch 92 is for starting rice cooking. The clock switch 93 switches between setting and canceling the clock adjustment mode. In the clock adjustment mode,
Using the hour switch 94 and the minute switch 95, the current time can be adjusted. The current time is, as shown in FIG.
It is displayed on the LCD 34 (current time display 111). The reservation switch 96 is used for cooking rice for reservation, and the reservation switch
When 96 is pressed, the display on the LCD 34 is switched to the display of the cooking reservation time, and in this state, the cooking reservation time can be set using the hour switch 94 and the minute switch 95. Thereafter, when the cooker switch 92 is pressed, the reserved cooker starts. When the switch 97 is pressed during the rice cooking operation, the reserved rice cooking operation, or the warming operation, these operations are stopped and the rice cooker is turned off. Insulation switch
Reference numeral 98 denotes a button for starting the heat retaining operation when pressed in the OFF state. The heat insulation selection switch 99 is for switching between a fresh heat insulation course (first heat insulation course) and a high heat insulation course (second heat insulation course) which will be described in detail later. That is, each time the heat insulation selection switch 99 is pressed, both heat insulation courses are alternately switched. The reset means 101 resets the microcomputer 91 to an initial state.

Actually, the rice cooking means 102, the reserved rice cooking means 103 and the heat retaining means 104 comprise the heating coil 21 and an inverter circuit for driving the same, the side heater 25 and the lid heater.
62 and the switching control element for driving them are hardware components and are configured as functions realized by the microcomputer 91, and are separated for convenience of explanation. The rice cooking means 102 is activated by pressing a rice cooker switch 92, and after performing rice cooking in a predetermined heating pattern, keeps the temperature. The reserved rice cooking means 103 is activated by pressing the rice cook switch 92 after pressing the reservation switch 96, and performs the rice cooking so as to finish the rice cooking at the set predetermined cooking reservation time, and then keeps the temperature. . In addition, in reserved rice cooking, besides setting the reserved cooking time as described above, the time until the cooking may be set. The warming means 104 is activated by pressing the warming switch 98 in the OFF state, and keeps warm.

In the heat retaining operation, the heating by the heating coil 21, the side heater 25 and the lid heater 62 is controlled so that the temperature of the pan 11 detected by the pan temperature sensor 23 becomes a predetermined temperature. In the fresh heat-retaining course, the heat is kept at a combination of a high temperature of 68 ° C. or more and a low temperature of 60 ° C. or more and less than 68 ° C. Further, in the above-mentioned high heat insulation course, heat insulation is performed mainly at a high temperature of 68 ° C. or more.
In other words, the temperature of the pot 11 is higher than that of the fresh heat retaining course, and is higher on average in the heat retaining course.

FIG. 2 shows a display unit. The current time is always displayed on the LCD 34 as shown in FIGS. 3A, 3B, and 3C (current time display 111). e) Current time display as shown in e)
In place of 111, the elapsed time from the start of heat retention is displayed in units of time (heat retention time display 112). The selected heat retention course is also displayed on the LCD 34, for example, with the characters "fresh" and "high" (heat retention course display 113).
On the other hand, the LEDs 35 are for displaying a process, and there are a total of three LEDs, some of which are lit during pre-cooking and before the start of cooking, those which are lit during cooking and those which are lit during heat retention. FIG. 2A shows a display in the off state. At this time, the current time is displayed on the LCD 34, and the fact that the fresh heat retention course is selected is displayed unless the user presses the heat retention selection switch 99.
Here, when the heat retention selection switch 99 is pressed to increase the heat retention course and switch to the heat retention course, the display of the selected heat retention course is also “high” as shown in FIG.
Switch to FIG. 2C shows the reset means 101.
When the microcomputer 91 is reset by
Or, a case where the power is restored from the power failure while the power failure backup power is turned off is shown. In these cases, the microcomputer 91 is brought into the initial state by the reset means 101. In this state, the time display on the LCD 34 flashes at 12:00 am, and the heat retention course is set to the fresh heat retention course. . FIG. 2 (d)
Shows a state in which the warming is being performed by the fresh warming course, and the LCD 34 displays the elapsed time from the start of the warming and the fact that the fresh warming course is selected. On the other hand, FIG. 2 (e) shows a state where the heat is kept on the higher heat keeping course, and L
On the CD 34, the elapsed time from the start of heat retention is displayed, and the fact that a higher heat retention course is selected is displayed.

FIG. 3 is a flowchart showing the function of selecting a heat retention course. Judgment of off state (Step S
1), determination whether the rice is being cooked (step S2), determination whether the rice is being reserved for cooking (step S3), determination whether the temperature is being kept warm (step S4), and determination whether the rice is in the initial state. The determination (step S5) is performed. If any of these, the switching operation of the heat retention course is accepted, and if not, the operation of switching the heat retention course is not accepted. Then, when the switching operation of the heat retention course is accepted, it is determined whether or not the heat retention selection switch 99 has been operated (step S6). If the heat retention selection switch 99 has been operated, the heat retention course is switched and operated. If not, the set heat retention course continues. That is, at least before starting the rice cooking by the rice cooking means 102, before starting the reserved rice cooking by the reserved rice cooking means 103, before starting the heat retention by the heat retaining means 104, during the heat retention by the rice cooking means 102, and during the reserved rice cooking means 103. During the warming by the warming means 104 and during the warming by the warming means 104, each time the warming selection switch 99 is pressed, the setting of the warming course is switched between the fresh warming course and the higher warming course.

FIG. 4 is a flowchart showing the warming operation. In the off state (step S11), the rice cooker switch
Press 92 to start cooking rice (steps S12, S13, S15
). At this time, if the cooked reservation time is called before the rice cook switch 92 is pressed, the rice cooker switch 92 is pressed and the reservation operation starts, and when the predetermined rice cook start time determined from the cooked reservation time comes, the rice cooker is started. Starts (steps S13, S14, S15). If you start cooking right away, or if you cook with reserved rice,
After the rice cooking, the heat retention starts automatically (step S19 or S20). Also, when the heat retention switch 98 is pressed in the OFF state, the heat retention starts (steps S18, S19 or S2).
0). In any case, the setting of the heat insulation course is determined at the time of starting the heat insulation (step S17), and if the heat insulation course is set, the heat insulation of the fresh heat insulation course starts (step S19), and the heat insulation course is started. If it has been set, the insulation of the high insulation course starts (step S20
).

In the fresh heat preservation course, the rice is preserved at a high temperature of about 68 ° C. to 76 ° C. immediately after the start of the heat preservation (step S21). The rice is kept warm by the low temperature (steps S22 and S23). Further, five hours after the start of the low-temperature keeping, the rice is kept at a high temperature of about 68 ° C. to 76 ° C. again (steps S24 and S25). On the other hand, in the high heat retention course, the rice is kept warm at a high temperature of about 68 ° C. to 76 ° C. (step S26). When the heat retention selection switch 99 is operated during the heat retention to switch the heat retention course, or when the temperature is switched from the fresh heat retention course to the higher heat retention course, the high temperature heat retention is performed unconditionally (steps S27 and S20). . On the other hand, when switching from the high heat retention course to the fresh heat retention course, the fresh heat retention course starts with low temperature heat retention (steps S28 and S23). This is particularly the case when switching from the high heat insulation course to the fresh heat insulation course is when the user who has been warming by the high heat insulation course to eat hot rice for meals, replaces the remaining rice after meals with the next meal. This is because it is assumed that the heat is kept for a long time until the time is reached. In such a case, since the user does not eat immediately after the switching of the heat retention course, the temperature is kept low immediately and the process quickly shifts to a heat retention process in which the rice can be kept in a good condition even when the temperature is kept for a long time.

FIG. 5 is a flowchart showing a case where 12 hours or more have passed after the completion of rice cooking. If there is no operation for selecting the heat retention course, the heat retention is performed on the set heat retention course (steps S31 and S32). On the other hand, if there is an operation of selecting the heat insulation course, the heat insulation course is switched, but the content of the fresh heat insulation course changes depending on whether or not the time of the operation is a predetermined time after the start of the heat insulation, for example, 12 hours or more. (Steps S33, S34, S35). That is, when the heat insulation course is switched from the high heat insulation course to the fresh heat insulation course, if 12 hours or more have elapsed since the start of the heat insulation, high-temperature insulation is performed (step S34), otherwise, low-temperature insulation is performed (step S35). . That is, the fresh heat retention course after 12 hours or more have elapsed from the start of the heat retention is substantially a higher heat retention course. However, in both cases, the display of the heat retention course becomes “fresh”.

The temperature for keeping the temperature at a low temperature may be at least 60 ° C., and it is preferable that the process is controlled to about 65 ± 5 ° C. to 63 ± 5 ° C. in consideration of variation. On the other hand, the high-temperature keeping temperature is preferably controlled to a temperature of about 78 ° C. from the upper limit of the variation of the low-temperature keeping temperature. Further, the high heat retention course is not limited to the one consisting only of high temperature heat retention as in the present embodiment, but may be any one that mainly has a high temperature heat retention, and may also incorporate a low temperature heat retention. The point is that it is only necessary that the warming and heating patterns of the fresh warming course and the higher warming course be different, and that the former average temperature be lower than the latter.

Further, in the fresh heat-retaining course, in addition to the control as in the present embodiment, the low-temperature heat-retention period may be executed plural times by time management, opening / closing operation management of the lid 51, and the like. For example, if a sudden temperature drop is detected by the temperature detection of the lid 51 by the lid temperature sensor 68, it is determined that the lid 51 has been opened, and if the temperature has been stabilized for about 0.1 to 1 hour from this state, a meal is taken. It is determined that the state where the lid 51 is closed after the completion of
Insulate at low temperature for about an hour. As a result, the time period during which no meal is performed is kept at a low temperature, and the setting for obtaining a good heat retention state without deterioration of rice is automatically made,
Usability and taste are improved.

As described above, according to the configuration of the above-described embodiment, in the rice cooker with the heat insulation function in which two heat insulation courses can be selected, the temperature of the low-temperature insulation is set to 60 ° C. or more, so that the time for eating Even if the zone is kept at a low temperature, it is possible to prevent a decrease in taste due to a low rice temperature. When comparing the taste by rice temperature experimentally, if the rice temperature is 60 ° C or higher, the taste that is not much different from that maintained at a higher temperature can be obtained, but if the rice temperature is lower than 60 ° C, The result was that the person felt extremely warm and the taste was reduced. Therefore, as in the present embodiment, if the low-temperature heat insulation is controlled at 65 ° C. ± 5 ° C. to 65 ° C. ± 3 ° C. in consideration of the variation, the heat insulation state can be improved without much lowering the taste.

Of course, if a high heat retention course is selected, it is possible to more reliably prevent a decrease in taste due to the rice temperature, while if a fresh heat retention course is selected, the heat retention state can be improved, and the rice can be prevented from deteriorating even after a long heat retention. it can.

As described above, usually, only the fresh heat-retaining course can be used to keep the rice in an appropriate temperature in terms of the storage stability of the rice and the taste depending on the temperature. Therefore, it is not necessary to select a heat-retention course. In addition to that, even if you select a heat retention course,
The user can switch the heat retention course before starting rice cooking, before starting the reserved rice cooking, before starting the heat retention, and at any time during the heat retention.
Good usability.

Further, if the user wants to switch after noticing the setting of the heat retention course after starting the rice cooking or the reserved rice cooking, the user can switch between the rice cooking and the reserved rice cooking as in the present embodiment. If it is, even after starting cooking rice or starting reserved rice cooking, there is no need to switch off once and select a heat insulation course. Therefore,
The rice cooker does not stop halfway and the cooked food does not worsen, and the troublesomeness of setting the reserved rice cooker again can be eliminated. Also, in the initial state, the heat insulation course can be selected.
Even when the device is reset to the initial state, a heat insulation course can be selected immediately, and the usability is improved.

Also, after cooking rice is finished and keeping warm, 12
When more than time passed, if the fresh warming course was selected, or if the fresh warming course was selected, it was not kept warm at a low temperature less than 68 ° C.
Even if the heat is kept for a long time, it is possible to prevent the rot of the rice due to the low temperature. On the other hand, since the heat retention course is set and displayed as intended by the user, it is possible to prevent a misunderstanding due to erroneous use such as not setting the low temperature heat retention.

Incidentally, even when the temperature is not set to a low temperature when 12 hours or more have elapsed since the start of the heat retention, for example, the temperature of the lid 51 controlled by the lid heater 62 is suppressed to reduce the temperature of the rice. The heat retention state can be improved by reducing the drying of the upper surface. In this way, if the heat retention is improved by other means for lowering the temperature in the fresh heat retention course, the heat retention suitable for the fresh heat retention course can be performed.

Further, when the heat insulation is stopped and the microcomputer 91 is turned off, or when the microcomputer 91 is brought into the initial state, the fresh heat insulation course is given priority and set.
The fresh heat retention that provides a good heat retention state is automatically set before cooking and before cooking rice, and the heat retention state can be kept good without the need to select a heat retention course, and the usability is improved. In addition, even if the power failure backup battery provided to hold various setting contents at the time of power failure runs out, the fresh heat retention course is automatically set with priority when the power is restored, so that the usability is improved.

FIG. 6 shows a pan 11 during cooking rice.
Is shown. The upper graph in FIG. 3 shows the change over time of the temperature detected by the pan temperature sensor 23, and the lower graph shows the amount of heating of the pan 11 by the heating coil 21. As shown in the figure, when rice cooking starts,
First, for example, a short-time cooking is performed with a weak heating amount for a predetermined time. Thereafter, the pan 11 is heated by the maximum amount of heating. Then, when it is detected that the inside of the pan 11 has become boiling based on the temperature detected by the pan temperature sensor 23, the heating amount is slightly reduced. However, as will be described later, it is necessary to increase the heating amount during this period to some extent in order to obtain a good cook. Then, when the water in the pot 11 runs out,
Although the temperature detected by the pan temperature sensor 23 rises rapidly, the cooking is detected, the heating of the pan 11 is stopped, and the spots become uneven for a predetermined time. As will be described in detail later, after the lumps stored in the steam port bucket 81 during the rice cooking are collected in the pot 11, the heating of the pot 11 is temporarily increased, and the additional cooking is performed. After the murara is finished, keep warm.

At the time of cooking rice, the steam generated in the pot 11 is
The pressure pushes the check valve 88 upward. for that reason,
The check valve 88 closes the required return hole 87 and prevents steam from entering the steam port bucket 81 from inside the required return hole 87. Then, when the pressure of the steam in the pan 11 further increases, the entire steam port bucket 81 is lifted. In this state, the steam containing the rice in the pot 11 passes from the open steam inlet 82 to the bottom of the steam port bucket 81, the steam passage hole 83, and collides with the upper and lower surface of the steam port cover 73. Sleep and steam separate. The tonnage having a large specific gravity is accommodated in the steam port bucket 81 through the through hole 84, and the steam is discharged from the steam discharge port 75 to the outside of the rice cooker. Therefore, the difficulty of the spill is determined by the amount of the sleeping lady that can be accommodated in the steam port bucket 81. At least in consideration of practical use, the internal volume of the steam port bucket 81 is desirably set to 40 ml or more.

When the cooking proceeds and the amount of heating decreases due to spots, the inside of the pan 11 cools down to a negative pressure state. This allows
The check valve 88 is deformed so as to be pulled into the pan 11, and the return hole 87 is opened. In this state, the rice collected in the steam port bucket 81 during the cooking of rice is collected in the pan 11 from the rice return hole 87. The tomb returns to the pot 11 after the temperature detected by the pot temperature sensor 23 has dropped to about 105 ° C. or less. It is. For this reason, it is desirable that all the bedding return to the pot 11 and start the additional cooking about 3 minutes after the start of spotting. Needless to say, these temperatures and times vary depending on the thickness of the pot 11 and the amount of heating until just before the spotting. As a result of the additional cooking, the inside of the pot 11 becomes hot again, and the rice falling from the steam port bucket 81 is dispersed, and the water near this area disappears. In addition, the steaming near the bottom of the pot 11 evaporates due to the additional cooking, thereby preventing the rice from becoming over-hydrated. In addition, at the time of this additional cooking, since there is no towel left in the steam port bucket 81, even if the towel rises somewhat in the steam port 57, it can be sufficiently accommodated in the steam port bucket 81, and It does not splatter from the vapor outlet 75.

By the way, in the conventional rice cooker that also serves as a jar, an inner lid that closes the upper opening of the pot is detachably provided below the lid body. The one without the lid has come to be used. Such a rice cooker without an inner lid has the advantage that there is no trouble in attaching and detaching the inner lid, there is no need to clean the inner lid, and the usability is good. On the other hand, spillage from the steam port, which was suppressed by the inner lid, is likely to occur. The amount of heating was reduced near or after boiling to reduce the pressure rise in the pot. For this reason, the amount of heating at the initial stage of boiling was insufficient compared with a rice cooker having an inner lid, resulting in uneven heating. And, due to this uneven heating, the rice is too soft at the bottom of the pot near the heating source and the lower part of the side of the pot, while the rice in the upper and middle parts of the rice far from the heating source (especially the center of the middle part) becomes hard, The cooking unevenness increased, and the rice cooking performance deteriorated. Also,
The water level of rice is visually inspected using the water level line marked on the pot as a guide, but there are variations in the water level position in production, variations and errors in water level with respect to the water level line, variations and errors in rice weighing, or In some cases, the amount of water with respect to rice is larger than usual, for example, because the user himself / herself wants to cook more softly according to his / her preference, so as to increase the amount of water. In such a case, since there is a large amount of water, it is easy for the spill to occur, and it is necessary to set the heating amount on the assumption that a certain amount of water will enter, and therefore,
In addition, the amount of heating was reduced, making it easier to cook.

As a solution to such a problem, a method is provided in which a bucket is provided in a steam port, a bed to be spilled is temporarily stored in the bucket, and the bed in the bucket is returned to the pot before cooking is completed. Was proposed. As a result, even a rice cooker without an inner lid can cook rice with less uneven cooking without reducing the amount of heating. But even with this method,
The rice is returned to the pot because the amount of heating was reduced and the pressure inside the pot was reduced, so the rice near the drop was still watery. . In addition, since the heating in the pot is concentrated on the bottom of the pot, the portion of the rice in contact with the bottom of the pot is overheated, and there is a problem that over-moisture remains in the rice in the vicinity.

On the other hand, in the rice cooker according to the present embodiment, the rice collected in the steam port bucket 81 is returned to the pot during rice cooking and before the steaming, and then the rice is cooked. The rice falling on the rice due to the heating of the rice is dispersed, so that the rice near the bottom of the steam port 57 does not become watery immediately after the completion of the rice cooking. Also,
By the additional cooking, the over-moisture state of the rice near the bottom of the pot 11 is reduced, and the cooked state is improved. Furthermore, since additional cooking is performed in a state where the towels are not accumulated in the steam port bucket 81, there is no possibility of spilling during additional cooking.

It should be noted that the present invention is not limited to the above embodiment, and various modifications can be made. For example,
In the above embodiment, the heat retention course is composed of two courses, a fresh heat retention course and a high heat retention course, but three or more heat retention courses may be provided by various combinations of high and low temperatures. If these three or more heat retention courses can be selected, the heat retention course can be selected according to the preference with more practicality. In the above-described embodiment, the main heating for cooking rice is performed by electromagnetic induction heating. However, the pot may be heated from the outside by a sheath heater or the like.

[0049]

According to the first aspect of the present invention, in the rice cooker with a heat retaining function capable of selecting the first heat retaining course and the second heat retaining course, the first heat retaining course has a high temperature of 68 ° C. or more. Insulation shall be performed at a combination of temperature and low temperature of 60 ° C. or more and less than 68 ° C. The second heat insulation course is mainly performed at a high temperature of 68 ° C. or more. In the case of selecting, it is possible to prevent a decrease in taste due to low rice temperature, and in particular, when the second heat retention course is selected, a better taste is obtained, while, when the first heat retention course is selected. In addition, it is possible to improve the heat retention state and prevent deterioration of the rice even when the heat is kept for a long time. In this way, usually, only the first heat insulation course can be appropriately used for heat insulation. In particular, it is not necessary to select the heat insulation course. Since it is possible before the start of rice cooking, before the start of the heat retention from the off state, and during the heat retention, it is possible to easily select and set the heat retention course, and the usability is good.

According to the rice cooker with the heat retaining function of the second aspect of the present invention, in addition to the effect of the first aspect of the present invention, the first heat retaining course is selected after a predetermined time has elapsed from the end of the rice cooking. In this case, or when selected, the rice is not kept warm at a low temperature of less than 68 ° C., so that even if the heat is kept for a long period of time, the rice can be prevented from spoiling. Further, even after a lapse of a predetermined time from the end of rice cooking, a heat retention course can be selected, so that misunderstanding of the user can be prevented.

According to the rice cooker with the heat retaining function of the third aspect of the present invention, in addition to the effect of the first aspect of the present invention, when the heat retention is stopped and the apparatus is turned off, or the control means is in the initial state. In this case, the first heat insulation course is set with priority, and it is displayed that the first heat insulation course is set, so that the first heat insulation course can be obtained, and appropriate first heat insulation course can be obtained. The course does not usually require the user to perform a selection operation, and is convenient.

[Brief description of the drawings]

FIG. 1 is a system block diagram showing one embodiment of a rice cooker with a heat retaining function of the present invention.

FIG. 2 is a front view of the display unit.

FIG. 3 is a flowchart showing a function of selecting a heat retention course according to the first embodiment.

FIG. 4 is a flowchart showing a heat retaining operation according to the first embodiment;

FIG. 5 is a flowchart showing a heat retaining operation according to the first embodiment;

FIG. 6 is a graph showing pan heating control during rice cooking.

FIG. 7 is a sectional view of the whole rice cooker.

[Explanation of symbols]

 91 Microcomputer (control means) 99 Heat insulation selection switch (heat insulation course selection means) 102 Rice cooking means 103 Reserved rice cooking means 104 Heat insulation means

Claims (3)

[Claims] 1. A first heat insulation course for keeping heat at a combination of a high temperature of 68 ° C. or more and a low temperature of 60 ° C. or more and less than 68 ° C., and a second heat insulation course for keeping heat mainly at a high temperature of 68 ° C. or more. A heating course selecting means for selecting a warming course, a rice cooking means for performing rice cooking and keeping warm after cooking, a reserved rice cooking means for keeping warm after finishing cooking at a predetermined time or a predetermined time, and an off state. And a control means for controlling the rice cooking means, the reserved rice cooking means and the heat retaining means based on the selection by the heat retention course selecting means, before starting the rice cooking by the rice cooking means, and Before starting pre-cooked rice by pre-cooked rice,
The first heat insulation course is selected by the heat insulation course selection means before starting heat insulation by the heat insulation means, during heat insulation by the rice cooking means, during heat insulation by the reserved rice cooking means, and during heat insulation by the heat insulation means. A rice cooker with a heat retention function, wherein the rice cooker can be selected from a second heat insulation course and a second heat insulation course. 2. After a predetermined time has elapsed from the end of rice cooking, if the first heat insulation course is selected, or if the first heat insulation course is selected, a low temperature of less than 68 ° C. The rice cooker with a heat retaining function according to claim 1, wherein the rice cooker is not kept warm. 3. When the heat retention is stopped and the state is turned off, or when the control means is brought into the initial state, the first heat retention course is set with priority, and the first heat retention course is set. The rice cooker with a heat retaining function according to claim 1, wherein the display indicates that a course is set.