JP2012016423A - Jar type rice cooker - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a jar type rice cooker that effectively lowers the risk of spoiling the cooked rice and deteriorating the food taste resulted from keeping the cooked rice warm.SOLUTION: The jar type rice cooker includes: a lid open/close detector 81 for detecting the open/close state of a lid 4 covering a pot 2; and a keep-warm temperature control section (not shown in Fig.) for controlling keep-warm temperatures for a keep warm mode selected at a keep-warm mode automatic selection section (not shown in Fig.). The rice cooker has: a first keep-warm mode, wherein the cooked rice is first kept warm at a second keep-warm temperature that is lower than a first keep-warm temperature, and then kept warm at a third keep-warm temperature that is higher than the first keep-warm temperature, which are repeated at least two times after a keep-warm operation starts; and a second keep-warm mode, wherein the transition timing between the second keep-warm temperature and the third keep-warm temperature is faster than first keep-warm mode. The rice cooker is configured such that the switching to the second keep-warm mode is carried out on the condition that the first keep-warm mode has been selected before the keep-warm operation starts and when the lid 4 is opened, and the frequency of transition between the first keep-warm mode and the second keep-warm mode is reduced when the lid 4 has not been opened even after the transmission timing between the first keep-warm mode and the second keep-warm mode passed.

Description

  The present invention relates to a jar rice cooker having a heat retaining function.

  Conventionally, in this type of jar rice cooker, cooked cooked rice has been kept warm at a constant temperature. For example, if the heat retention temperature is low, the cooked rice will rot, so that the cooked rice is prevented from being spoiled, and the temperature of the cooked rice is kept at a temperature in the range of about 70 ° C. to 74 ° C. It was set.

  However, in the rice cooker having the above configuration, since the heat retention temperature is relatively high, in fact, if the heat is kept for a long time, the cooked rice turns yellow (brown), emits a unique odor, and tastes such as stickiness and elasticity There is a problem that the physical properties deteriorate.

  Therefore, from a normal heat retention temperature (for example, a temperature within a range of 70 ° C. to 74 ° C.), a high temperature heat retention temperature (for example, a temperature within a range of 75 ° C. to 95 ° C.) higher than the normal heat retention temperature, and a normal heat retention temperature. In addition, it has three levels of heat retention temperatures, such as a low temperature heat retention temperature (for example, a temperature in the range of 55 ° C. to 69 ° C.) with a low heat retention temperature, and by performing cycle heating that switches those heat retention temperatures every predetermined time, A jar rice cooker that solves the problem has been proposed (see, for example, Patent Document 1).

  In addition, by allowing the user to select a heat retention mode that transitions to a normal heat retention temperature and a heat retention mode that consists only of a normal heat retention temperature after alternately repeating a low temperature heat retention temperature and a high temperature heat retention temperature for a certain period of time, There has also been proposed a jar rice cooker that effectively reduces the deterioration of taste caused by rotting of rice and heat retention (see, for example, Patent Document 2).

Japanese Patent No. 2814915 Japanese Patent No. 2891118

  The rotting bacteria in the pan of the jar rice cooker keeps 100 ℃ for about 20 minutes during cooking, so most bacteria are sterilized, so if you keep the lid closed after cooking, Bacteria will not enter the pot of the jar rice cooker.

  However, in the configuration of the conventional jar rice cooker as described in Patent Documents 1 and 2, the cycle of the normal heat retention temperature, the high temperature heat retention temperature, and the low temperature heat retention temperature is set in the same manner regardless of opening and closing of the lid. Therefore, the effect of reducing the deterioration of the taste due to the spoilage and heat retention of the cooked rice was insufficient.

  The present invention has been made in order to solve the conventional problems as described above, and an object of the present invention is to provide a jar rice cooker that can further effectively reduce the deterioration of taste caused by rotting and heat retention of cooked rice. It is what.

In order to solve the above-mentioned conventional problems, the jar rice cooker of the present invention is housed in the rice cooker body, and can contain cooked rice, an openable lid that covers the upper opening of the pan, and the above A heating means for heating the pan, a pan temperature detection sensor for detecting the temperature of the pan, a heating control unit for controlling the heating operation of the heating means, and a corresponding warming mode from a plurality of warming modes automatically. Based on the heat retention mode automatic selection section to be selected, the heat retention mode selected by the heat retention mode automatic selection section, and the detected temperature detected by the pan temperature detection sensor, the heat control section is controlled to control the heat retention temperature. And a lid opening / closing detection device for detecting opening / closing of the lid, and the heat retaining step includes a first heat retaining temperature which is a normal heat retaining temperature, and a second heat retaining temperature lower than the first heat retaining temperature, Higher than the first heat retention temperature A first heat-retaining mode in which the cooked rice is warmed at the second warming temperature at least twice after the start of warming, and then transferred to the third warming temperature to warm the cooked rice; and the second warming temperature A second heat retention mode in which only the timing of shifting from the temperature to the third heat retention temperature is made faster than the first heat retention mode, and the heat retention mode automatic selection unit has a heat retention mode automatically selected before the start of the heat retention. When it is in the first heat retention mode and the lid opening / closing detection device detects that the lid has been opened, it is automatically selected to switch to the second heat retention mode, and the lid opening / closing detection device is If it is not detected that the lid has been opened even after the timing of shifting from the second heat retention temperature to the third heat retention temperature in the first heat retention mode, the first heat retention mode and the second heat retention mode are used. The frequency of transition from the second heat retention temperature to the third heat retention temperature is reduced, and the timing and frequency of transition from the second heat retention temperature to the third heat retention temperature can be varied depending on whether or not the lid is opened and closed. In addition, since heat retention is performed according to the difference in the growth of spoilage bacteria by opening and closing the lid, it is possible to more effectively reduce the taste deterioration due to the spoilage and heat retention of cooked rice.

  The jar rice cooker of the present invention can vary the timing and frequency of transition from the second heat retention temperature to the third heat retention temperature depending on whether or not the lid is opened and closed, and the difference in the growth of spoilage bacteria due to the opening and closing of the lid. Since the corresponding heat retention is carried out, it is possible to more effectively reduce the deterioration of the taste due to the spoilage of the cooked rice and the heat retention.

Sectional drawing of the jar rice cooker concerning the 1st Embodiment of this invention Block diagram showing the configuration related to the control unit of the jar rice cooker Top view of the operation panel of the jar rice cooker The graph which shows the change of the thermal insulation temperature in the standard thermal insulation mode in the jar rice cooker

1st invention is stored in the inside of a rice cooker main body, the pan which can accommodate cooked rice, the lid | cover which can be opened and closed which covers the upper opening part of the said pan, the heating means which heats the said pan, and the temperature of the said pan A pan temperature detection sensor for detecting the heat, a heating control unit for controlling the heating operation of the heating means, a heat retention mode automatic selection unit for automatically selecting a corresponding heat retention mode from a plurality of heat retention modes, and the heat retention mode Based on the heat retention mode selected by the automatic selection unit and the detected temperature detected by the pan temperature detection sensor, the heat control unit that controls the heat control temperature by controlling the heating control unit, and the opening and closing of the lid A lid opening / closing detection device for detecting, and the heat retaining step includes a first heat retaining temperature that is a normal heat retaining temperature, a second heat retaining temperature that is lower than the first heat retaining temperature, and a third heat retaining temperature that is higher than the first heat retaining temperature. At least after the start of heat insulation The first temperature mode in which the cooked rice is warmed at the second warming temperature and then transferred to the third warming temperature to keep the cooked rice, and the timing of the transition from the second warming temperature to the third warming temperature. A second heat-retaining mode in which only the heat-retaining mode is made faster than the first heat-retaining mode, and the heat-retaining mode automatic selection unit is configured such that the heat-retaining mode automatically selected before the heat-retaining is the first heat-retaining mode and When the opening / closing detection device detects that the lid has been opened, it is automatically selected to switch to the second heat retention mode, and the lid opening / closing detection device is selected from the second heat retention temperature in the first heat retention mode. If it is not detected that the lid has been opened even after the timing of transition to the third heat retention temperature, the second heat retention temperature in the first heat retention mode and the second heat retention mode is changed to the third heat retention temperature. Transfer The timing and frequency of transition from the second heat retention temperature to the third heat retention temperature can be varied depending on the presence / absence and timing of the lid opening / closing, and depending on the growth of spoilage bacteria due to the lid opening / closing Therefore, it is possible to more effectively reduce the deterioration of the taste caused by the decay of the cooked rice and the heat retention.

  In the second invention, in particular, the frequency at which the second keeping temperature is decreased from the second keeping temperature of the first invention to the third keeping temperature is determined by the lid open / close detection device from the second keeping temperature in the first keeping mode to the third keeping temperature. The number of times that the timing of transition to the heat retaining temperature has passed is determined, and the frequency of transition from the second heat retaining temperature to the third heat retaining temperature can be reduced by the number of times past the opening and closing of the lid, depending on the timing of opening and closing the lid. Furthermore, since the heat insulation according to the difference in the proliferation of spoilage bacteria by opening and closing the lid is carried out, it is possible to further effectively reduce the deterioration of the taste due to the spoilage of the cooked rice and the heat insulation.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. Note that the present invention is not limited to the embodiments.

(Embodiment 1)
The jar rice cooker concerning the 1st Embodiment of this invention is demonstrated below using FIGS. 1-4. FIG. 1 is a cross-sectional view of a jar rice cooker according to a first embodiment of the present invention, FIG. 2 is a block diagram showing a configuration related to a control unit of the jar rice cooker, and FIG. 3 is a jar rice cooker. FIG. 4 is a graph showing a change in the heat retention temperature in an example of the heat retention mode of the jar rice cooker.

  The jar rice cooker in the present embodiment is an electric IH heating jar rice cooker. 1-3, the jar rice cooker of this Embodiment is accommodated in the inside of the main body 1 so that attachment or detachment is possible, and it opposes the outer peripheral surface of the pan 2 which can accommodate cooked rice, and the pan 2 accommodated in the main body 1. A heating unit 3 that serves as a heating means for heating the pan 2, a lid 4 that is openably and closably attached to the main body 1 so as to cover the upper opening 2 d of the pan 2, and the bottom center of the pan 2 The pot of the heating unit 3 is disposed inside the lid 4 and the lid bottom temperature sensor 5, which is an example of a pot temperature detection sensor that circumscribes the temperature of the pot 2, and is based on the detected temperature of the pot bottom temperature sensor 5. The heating control part 71 which controls heating operation is controlled, the pot 2 is heated, and the control part 6 which cooks and heat-maintains the to-be-heated material in the pot 2 is provided.

  The main body 1 has a substantially cylindrical shape with an open top, that is, a substantially bottomed cylindrical shape, and forms a rice cooker body. A ring-shaped upper frame 11 is fitted and attached around the upper opening of the main body 1. The upper frame 11 fixes the upper end part of the coil base 12 formed in the bottomed cylindrical shape, and the pot base part is formed with the coil base 12.

  On the outer peripheral surface of the coil base 12, a ring-shaped bottom inner coil 31, bottom outer coil 32, and side coil 33 are installed so as to be opposed to the outer peripheral surface of the pan 2 and inductively heat the pan 2. Yes. The bottom inner coil 31 is disposed so as to face the bottom 2a of the pan 2, the bottom outer coil 32 is disposed so as to face the side bottom 2b of the pan 2, and the side coil 33 is disposed on the side 2c of the pan 2. It arrange | positions so that it may oppose. The heating unit 3 includes a bottom inner coil 31, a bottom outer coil 32, a side coil 33, and a lid coil 34 described later.

In the space formed by the coil base 12 and the inner surface of the main body 1, a high-frequency current is passed through the bottom inner coil 31, the bottom outer coil 32, the side coil 33, and a lid coil 34 described later under the control of the control unit 6. And the heating control part 71 for induction-heating the pan 2 is installed. A heat sink 73 for cooling the heat generating component 72 installed on the heating control unit 71 is installed below the heating control unit 71. A cooling fan motor 74 for cooling the heat sink 73 is provided below the heat sink 73. The surface of the cooling fan motor 74 facing the coil base 12 is inclined so as to follow the shape of the coil base 12.

  The lid 4 is detachably attached to the outer lid portion 41 formed of synthetic resin, the inner lid portion 42 fitted and attached to the inner side of the outer lid portion 41, and the lower surface of the inner lid portion 42. And a heat generating plate 43 constituting the lower surface of the lid 4.

  On the upper surface of the inner lid portion 42, a ring-shaped lid coil 34 for inductively heating the heat generating plate 43 is installed. The lid 4 is rotatably supported by a hinge member 13 integrally formed on a part of the upper frame 11 of the main body 1 with a hinge shaft 4 a provided on a part of the inner lid portion 42. It is attached so that the upper opening part of can be opened and closed.

  A ring-shaped pot packing 44 is attached to the lower part of the outer periphery of the heat generating plate 43. The pot packing 44 is disposed so as to close the gap between the pot 2 and the lid 4 so that steam generated in the pot 2 during cooking rice does not flow into the internal space of the main body 1. A lid temperature sensor 45 for detecting the temperature of the heat generating plate 43 is pressed against a part of the upper surface of the heat generating plate 43. Further, a steam passage hole 46 for discharging the steam in the pan 2 to the outside of the rice cooker is provided at the center of the heat generating plate 43.

  A through hole 47 is provided at the center of the lid 4 so as to penetrate in the thickness direction of the lid 4. The through-hole 47 is provided with a lid opening / closing detection unit 81 as a lid opening / closing detection device that detects opening / closing of the lid 4. The lid open / close detection unit 81 includes a steam cylinder 82, a magnet 83, and a reed switch 84. As shown in FIG. 1, the steam cylinder 82 has a substantially cylindrical shape, and is fitted into the through hole 47 from the outside of the jar rice cooker.

  The steam cylinder 82 is formed with an inclined portion 82a that is inclined downward as it moves away from the hinge shaft 4a. On the inclined portion 82a, a spherical magnet 83 is arranged so as to roll and move. The magnet 83 is located at a position far from the hinge shaft 4a (the position indicated by the solid line in FIG. 8) when the lid 4 is closed, and when the lid 4 is opened, it rolls on the inclined portion 48b and is close to the hinge shaft 4a. It moves to a position (position indicated by a dotted line in FIG. 1).

  A reed switch 84 is installed in the vicinity of the far position inside the lid 4. The reed switch 84 is turned on and off when the magnet 83 rolls along the inclined portion 82a by opening and closing the lid 4 and moves away from or approaches the far position. The open / closed state of the lid 4 can be detected by turning the reed switch 84 on and off.

  The pan bottom temperature sensor 5 is provided on the coil base 12 and is urged by a sensor spring 51 for supporting the pan 2, so that the pan bottom temperature sensor 5 can be circumscribed at the center of the bottom 2 a of the pan 2. This pan bottom temperature sensor 5 is installed so that the control part 6 can control the to-be-heated object (rice cooked rice) in the pan 2 in the optimal temperature state by detecting the temperature of the pan 2 at the time of rice cooking and heat retention. .

  Inside the lid 4 and above the lid temperature sensor 45, a control unit 6, an operation board 61, an information input unit 62, and a display plate 63 as an example of a display unit are installed. On the outer lid portion 41, a display window 41a that allows the display plate 63 to be visually recognized from the outside of the rice cooker, and pressing each input button such as the rice cooking button 62d and the off button 62e of the information input unit 62 by pressing from the outside of the rice cooker An operation panel 41b that can be used is provided.

  The control unit 6 controls the heating control unit 71 based on the detected temperatures of the pan bottom temperature sensor 5 and the lid temperature sensor 45 to finish the rice cooking operation of the rice cooking control unit 6b that performs the rice cooking operation and the rice cooking control unit 6b. It detects, and based on the detection temperature of the pan bottom temperature sensor 5 and the lid temperature sensor 45, the heating control part 71 is controlled, and the thermal insulation temperature control part 6c which controls the thermal insulation temperature of the cooked rice is provided. In addition, the control part 6 is controlling the time required for each process in rice cooking and heat retention by the time measuring part 64 provided separately.

  In the present embodiment, the heat retention mode is a low temperature heat retention temperature (second heat retention temperature, for example, 55 ° C. to 69 ° C.) lower than a normal heat retention temperature (first heat retention temperature, for example, a temperature within a range of 70 ° C. to 74 ° C.). 1st heat retention which shifts to normal heat retention temperature after repeating alternately high temperature heat retention temperature (3rd heat retention temperature, for example, temperature within the range of 74 to 95 degreeC) higher than normal heat retention temperature. A standard heat retention mode which is an example of the mode and a second heat retention mode in which the timing of transition from the low temperature heat retention temperature to the high temperature heat retention temperature is faster than the standard heat retention mode. In the present embodiment, in the first heat retaining mode, the cooked rice is warmed at least twice at the second heat retaining temperature and then shifted to the third heat retaining temperature. FIG. 4 shows an example of changes in the temperature of the pan 2 and the temperature of cooked rice in the standard heat retention mode.

  In general, after cooking, the user is supposed to open and close the lid 4 once in the middle of heat insulation in order to loosen the rice and eat it in small portions. Escapes to the outside of the rice cooker, the temperature of the cooked rice drops, and the cooked rice is likely to rot.

  For this reason, in this embodiment, when the lid open / close detection unit 81 detects the open / closed state of the lid 4 after the start of the thermal insulation in the standard thermal insulation mode, the thermal insulation mode automatic selection unit 6a performs the low temperature insulation as shown in FIG. The second heat retention mode in which the total power consumption from the start of heat retention to a preset time (for example, 12 hours) is increased compared to the standard heat retention mode by making only the timing from temperature to the high temperature heat retention temperature faster than the standard heat retention mode. It is configured to automatically switch and select. Further, the spoilage bacteria in the pan 2 of the jar rice cooker keeps 100 ° C. for about 20 minutes during cooking, so most of the bacteria are sterilized. If the lid 4 is kept closed after cooking, new spoilage bacteria will not enter the pan 2 of the jar rice cooker. Therefore, in the state where lid 4 is kept closed after rice cooking is completed, it is possible to keep the temperature at a low temperature.

  Therefore, in the standard heat retention mode, when the lid 4 remains closed even after the timing of transition from the low temperature heat retention temperature to the high temperature heat retention temperature, the lid open / close detection unit 81 detects the open / closed state of the lid 4 thereafter. Including the transition to the second warming mode, the frequency of transition from the low temperature warming temperature to the high temperature warming temperature is reduced by the number of times past the timing of transition from the low temperature warming temperature to the high temperature warming temperature in the standard warming mode. In addition, it is configured to automatically switch and select a heat retention mode in which the total power consumption from a heat retention start to a preset time (for example, 12 hours) is further reduced.

  When the rice cooking button 62d of the information input unit 62 is pressed, the warming temperature control unit 6c is instructed to start operations such as rice cooking, and the off button 62e is instructed to cancel each operation when pressed.

  The display board 63 displays rice cooking information and date / time input by the information input unit 62. In addition, the display board 63 may be provided with a cumulative power consumption calculation unit (not shown) that calculates the cumulative power consumption from the start of heat insulation to the present, so that the cumulative power consumption can be displayed. By comprising in this way, an energy saving can be promoted by displaying a use electric power charge to a user.

  According to the jar rice cooker in the present embodiment configured as described above, the lid open / close detection unit 81 that detects opening / closing of the lid 4 is provided, and is automatically selected by the heat insulation mode automatic selection unit 6a before the start of heat insulation. When the warming mode is the standard warming mode and it is detected that the lid 4 is opened, the warming mode automatic selection unit 6a automatically consumes the total time from the start of warming to a preset time (for example, 12 hours). Since it is configured to select and switch to the second heat retention mode in which the amount of electric power is larger than the standard heat retention mode, the heating amount of the heating unit 3 after opening and closing the lid 4 increases, the temperature of the cooked rice rises, and the cooked rice is spoiled Can be prevented.

  In addition, the mode automatically switches from the second heat insulation mode to the standard heat insulation mode, and in the state where the lid 4 remains closed even after the timing of transition from the low temperature heat insulation temperature to the high temperature heat insulation temperature in the standard heat insulation mode, Including the case where the lid open / close detection unit 81 detects the open / closed state of the lid 4 and shifts to the second heat retention mode, the frequency of transition from the low temperature heat retention temperature to the high temperature heat retention temperature is reduced once and preset from the start of the heat retention. Since it is configured to automatically switch and select the heat retention mode that further reduces the total power consumption until the specified time (for example, 12 hours), the burden on the user is reduced, saving the user trouble, It is possible to more effectively reduce the taste deterioration due to the decay and heat retention of cooked rice.

  Also, only when necessary (when the lid 4 is opened / closed), the mode is automatically switched to the standard heat insulation mode, and the heat is normally kept in the second heat insulation mode with low total power consumption. If the lid 4 remains closed even after the timing of transition to temperature, the frequency of transition from the low temperature insulation temperature to the high temperature insulation temperature is set to the timing of transition from the low temperature insulation temperature to the high temperature insulation temperature in the standard insulation mode. Since it is configured to reduce the number of times that have passed, energy saving can be achieved efficiently.

  In addition, in the jar rice cooker in this Embodiment, the heating unit 3 is comprised with the coil 31 in the bottom, the coil 32 outside the bottom, the side coil 33, and the cover coil 34, and the to-be-cooked object in the pan 2 is comprised. Although it comprised so that it might heat from the cover 4 side which covers the bottom side of the pan 2, the side surface side of the pan 2, and the upper opening part 2d of the pan 2, this invention is not limited to this.

  The heating unit 3 should just be provided with the heating means which heats the bottom side of the pan 2 at least. That is, the jar rice cooker in the present embodiment only needs to include the bottom inner coil 31 or the bottom outer coil 32.

  Moreover, in the rice cooker in this Embodiment, although all the heating units 3 were comprised with the coil, it is not restricted to a coil, You may comprise with the combination of a heater, a heater, and a coil.

  In the above embodiment, the lid opening / closing detection unit 81 is configured by the steam cylinder 82, the magnet 83, and the reed switch 84 as an example. However, the present invention is not limited to this, and any other configuration is possible. Therefore, it may be configured to detect the opening and closing of the lid 4.

  As mentioned above, although embodiment of this invention has been described, this invention is not limited to the said embodiment, A various deformation | transformation is possible. Moreover, it cannot be overemphasized that the said embodiment can be implemented also in the jar rice cooker of the other system controlled by a microcomputer.

  The jar rice cooker according to the present invention is useful as a jar rice cooker having a heat retaining function because it can provide a jar rice cooker that can more effectively reduce the taste deterioration due to the decay and heat retention of the rice.

1 body 2 pan 3 heating unit (heating means)
4 Lid 5 Pan bottom temperature sensor (Pot temperature detection sensor)
71 Heating Control Unit 81 Lid Open / Close Detection Unit (Lid Open / Close Detection Device)

Claims (2)

A pot that is housed inside the rice cooker body and can contain cooked rice, an openable / closable lid that covers the upper opening of the pot, a heating means that heats the pot, and a pot temperature detection that detects the temperature of the pot Selected by a sensor, a heating control unit that controls the heating operation of the heating means, a heat retention mode automatic selection unit that automatically selects a corresponding heat retention mode from a plurality of heat retention modes, and the heat retention mode automatic selection unit. And a lid opening / closing detection device for detecting the opening / closing of the lid by controlling the heating control unit based on the detected temperature detected by the pan temperature detection sensor and the heating control unit. The heat retention step includes a first heat retention temperature that is a normal heat retention temperature, a second heat retention temperature lower than the first heat retention temperature, and a third heat retention temperature higher than the first heat retention temperature. At least twice Only the first heat-retaining mode in which the cooked rice is warmed at the heat-retaining temperature and then transferred to the third heat-retaining temperature to retain the cooked rice, and the timing for shifting from the second heat-retaining temperature to the third heat-retaining temperature is the first heat-retaining temperature. A second heat-retaining mode that is faster than the mode, and the heat-retaining mode automatic selection unit is configured such that the heat-retaining mode automatically selected before the start of heat-retaining is the first heat-retaining mode, and the lid open / close detection device is the lid When opening is detected, the switch is automatically switched to the second heat retention mode, and the lid opening / closing detection device shifts from the second heat retention temperature to the third heat retention temperature in the first heat retention mode. If it is not detected that the lid has been opened even after the timing to perform, the frequency of shifting from the second heat retention temperature to the third heat retention temperature in the first heat retention mode and the second heat retention mode is reduced. Rice cooker characterized by comprising Te. The frequency of shifting from the second warming temperature to the third warming temperature to be reduced is the number of times that the lid opening / closing detection device has passed the timing of transitioning from the second warming temperature to the third warming temperature in the first warming mode. The jar rice cooker of Claim 1 characterized by these.