JP2003290033A - Rice cooker - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To optimize heating quantity to a side surface of a pan after concluding a rice cooking process. <P>SOLUTION: A cover temperature sensor 57 for originally detecting temperature of a cover body 5 is used to detect temperature of the cover body 5 just after starting rice-cooking. In response to detected temperature, heating quantity to the side surface of the pan 11 by a cord heater 26 after concluding rice- cooking is changed. Heating quantity to the side surface of the pan 11 after concluding rice-cooking can be thereby optimized without providing a new temperature detecting means. <P>COPYRIGHT: (C)2004,JPO

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rice cooker for cooking and heating an object to be cooked in a pan by a heating means. [0002] Conventionally, in this type of rice cooker, after the rice cooking process of cooking the food to be cooked in the pan is finished, the process shifts to murmur and keeps the temperature at a predetermined temperature. Until then, the pan was heated at a constant heating amount regardless of the room temperature, or the pan was heated at a heating amount corresponding to the pan temperature. Therefore, when the room temperature is low, the side of the pan is easy to cool, the amount of heating to the side of the pan is insufficient, water drops adhere to this side, and the rice around the pan becomes watery. Conversely, when the room temperature is high, the side of the pan is difficult to cool, the amount of heating to the side of the pan becomes excessive, and the rice around the pan dries, which in each case is a factor that degrades the taste. Thus, in providing delicious rice, how to adjust the amount of heating to the side of the pan in consideration of the effect of room temperature has become an important issue. An object of the present invention is to provide a rice cooker capable of optimizing the amount of heating to the pan after the completion of the rice cooking process. [0004] A rice cooker according to the present invention comprises a lid for covering the upper surface of a pan with a temperature detecting means, and a rice cooker that automatically keeps the temperature from cooking rice. According to the temperature of a temperature detection means, it is comprised so that the heating of the said pan after rice cooking may be varied. In this case, originally, the temperature of the lid after cooking is detected by using a temperature detecting means for detecting the temperature of the lid.
Depending on the detected temperature, the heating of the pan after the completion of cooking can be varied. Therefore, even if it does not increase a new temperature detection means, the heating amount of the pan after the rice cooking process can be optimized at a low cost. [0006] The temperature detected by the temperature detecting means immediately after cooking is hardly affected by the water temperature in the pan. Moreover, even when cooking rice immediately after heat insulation, the temperature of a cover body has fallen to room temperature in the meantime, and the heating to the pan which considered the influence of room temperature can be performed correctly. DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the rice cooker according to the present invention will be described below with reference to FIGS. In addition, the rice cooker in a present Example is a rice cooker which performs cooking heating, such as rice cooking and heat retention. In FIG. 1, reference numeral 1 denotes a cooker body, that is, a rice cooker body. The rice cooker body 1 is composed of a substantially cylindrical outer frame 2 and a bottom plate 3 provided so as to cover the lower surface opening of the outer frame 2. An outer shell is formed. On the upper side of the rice cooker body 1, a lid 5 is supported by a hinge shaft 4 located at the rear thereof so as to be freely rotatable. Further, the substantially cylindrical inner frame upper part 6 formed by hanging down integrally from the upper inner peripheral part of the outer frame 2 and the inner frame 7 provided so as to cover the lower surface opening of the inner frame upper part 6 are used for cooking rice. A bottomed cylindrical pot accommodating portion 8 is formed in the vessel body 1. In addition, the inner frame upper part 6 which makes the side part of the pan accommodating part 8 consists of synthetic resins, such as PP (polypropylene) integrated with the outer frame 2. As shown in FIG. Further, the inner frame 7 that forms the bottom of the pot housing 8 is P
It is made of a synthetic resin such as ET (polyethylene terephthalate). [0009] Inside the pot accommodating portion 8, a bottomed cylindrical pot 11 for accommodating an object to be cooked such as rice or water is detachably accommodated. This pan 11 is a pan body 12 mainly made of aluminum with good thermal conductivity, and a heating element 13 made of a magnetic metal plate such as ferritic stainless steel joined from the lower side to the bottom of the outer surface of the pan body 12. It consists of. pot
11 does not have a heating element 13 from the center of the side to the top.
This is to reduce the weight. An annular flange portion 14 is formed around the upper end of the pan 11 so as to extend to the outer periphery thereof. The inner frame 7 is located opposite to the heating element 13 of the pan 11, and the inner frame 7 has an outer surface on the lower side and the bottom face facing the heating element 13. A heating coil 16 is provided as a pan heating means for electromagnetically heating the bottom. When a high-frequency current is supplied to the heating coil 16, the pan is generated by an alternating magnetic field generated from the heating coil 16.
The eleven heating elements 13 generate heat, and the pot 11 and thus the food to be cooked such as water and rice in the pot 11 are heated. further,
A ferrite core 17 is provided so as to cover the heating coil 16 from below. A thermistor-type pan temperature sensor as a pan temperature detecting means for detecting the temperature of the bottom of the pan 11 by resiliently contacting the outer surface of the bottom of the pan 11 is provided at the center of the bottom of the inner frame 7.
21 is supported by the sensor holder 22, and a temperature fuse 23 is provided in the vicinity of the pan temperature sensor 21. At the upper end of the pot accommodating portion 8 of the rice cooker body 1, a cord heater 26 as a pot side heating means for heating the upper portion of the pan 11, particularly the flange portion 14, is provided. It is located on the lower side and is arranged in an annular shape.
The cord heater 26 includes a spacer 27 as a heat dissipation suppressing member attached so as to be placed on the upper end of the pot accommodating portion 8, a cord heater 28 that is an electric heater held on the spacer 27, The cord heater 28 is attached to the spacer 27 so as to cover it from above, and is composed of a metal plate 29 that serves both as a fixing bracket made of, for example, an aluminum plate and a heat radiating portion, which is excellent in thermal conductivity. This metal plate
29 is located facing the gap 30 between the rice cooker body 1 and the lid 5. Then, the lower surface of the flange portion 14 of the pan 11 is placed on the upper surface of the metal plate 29, so that the pan 11 is accommodated in the pan accommodating portion 8 in a suspended state. Therefore, there is almost no gap between the pot 11 and the upper end of the pot accommodating portion 8 in which the pot 11 is accommodated. Moreover, the flange portion 14 of the pan 11 has an outer shape that is equal to or greater than the size of the cord heater 26, so that the cord heater 26 is covered with the flange portion 14 of the pan 11 from above. . However, although not shown, for example, by bending the cord heater 26 downward at the left and right side portions of the pot accommodating portion 8, the flange portion 14 and the cord heater 26 are brought into non-contact with each other. A gap is partially formed between them, and the flange portion 14 can be used as a handle portion when the pan 11 is attached and detached in this gap. Further, the gap also has an action of discharging steam when cooking rice with water attached to the outer surface of the pan 11. Furthermore, in the space outside the pot accommodating portion 8 in the rice cooker body 1, the position behind the pot accommodating portion 8 is
A cord reel 36 for power supply and a heating substrate 37 for controlling heating adjustment by the heating coil 16 are provided. The lid 5 is urged in the opening direction by the force of a hinge spring 41 wound around the hinge shaft 4 which is a rotating shaft thereof. Also, a clamp provided at the front of the lid 5
An open / close button 43 provided on the upper front side of the outer frame 2 is detachably engaged with 42 so that the lid 5 is held in a closed state. The lid 5 includes an outer lid 46 that forms an outer shell of the upper surface, a heat radiating plate 47 as a lid lower surface material that forms a lower surface that is the inner surface of the lid 5, and the outer lid 46 and the heat radiating plate 47. The main component is an outer lid cover 48 as a lid base material that is joined to form a skeleton of the lid body 5. An inner lid 51 that directly covers the upper opening of the pan 11 is detachably mounted on the lower surface, which is the inner surface of the lid 5, with a predetermined gap formed between the lower surface and the lower surface. The heat radiating plate 47 and the inner lid 51 are both made of metal, and are made of, for example, a material obtained by anodizing stainless steel or aluminum.
Further, a packing base 52 is fixed to the outer peripheral portion of the inner lid 51, and a lid packing 53 is fixed by being sandwiched between the packing base 52 and the inner lid 51. This lid packing
53 is formed in an annular shape by an elastic member such as silicone rubber or fluorine rubber, and abuts on the upper surface of the flange portion 14 of the pan 11 to close the gap between the pan 11 and the inner lid 51, and is generated from the pan 11. It is intended to seal off steam. A contact portion of the lid packing 53 with the pan 11 is opposed to the cord heater 26 with the flange portion 14 interposed therebetween. Also, a heat radiating plate is provided inside the lid 5.
On the upper surface of 47, a lid heater 56 as a lid heating means is provided. The lid heater 56 may be an electric heating heater such as a cord heater or a heating coil by electromagnetic induction heating. Further, the heat radiating plate 47 is provided with a thermistor type lid temperature sensor 57 as lid temperature detecting means for detecting the temperature of the lid 5, particularly the inner lid 51. A steam port 61 for releasing the steam generated in the pan 11 to the outside is detachably attached to the upper rear portion of the lid 5. Further, in the heat radiating plate 47 and the inner lid 51, at positions below the steam port 61, opening holes 62 and 63 for passing steam are respectively formed. The lower end of the steam port 61 has a steam port packing.
64 is provided. Further, an operation panel is provided at the front of the outer lid 46.
71 is provided. A display substrate 73 is disposed in a substrate storage chamber 72 formed in the lid 5 below the operation panel 71, and the display substrate 73 has a display LC.
D74, switch 75, etc. are attached. Reference numeral 76 denotes an operation button for operating the switch 75. The control system of this rice cooker will be described with reference to FIG. In the figure, 81 is a control means comprising a microcomputer or the like, which is a heating coil for heating the bottom of the pan 11 during cooking and keeping warm based on the temperature information from the pan temperature sensor 21 and the lid temperature sensor 57. 16, a cord heater 26 that heats the side of the pan 11, and a lid heater 56 that heats the lid 5. In particular, the control means 81 of the present embodiment mainly controls the heating coil 16 based on the temperature detected by the pan temperature sensor 21, performs temperature management of the bottom of the pan 11, and based on the temperature detected by the lid temperature sensor 57. The lid heater 56 is mainly controlled so that the temperature management of the heat radiating plate 47 and the inner lid 51 is performed. The control means 81 includes cooking control means for controlling cooking heating of the cooking object as a function on the control sequence of the program stored in its own storage means (not shown). A rice cooking control means 82 for cooking and heating the food to be cooked in 11 and a heat keeping control means 83 for keeping the rice in the pan 11 warm to a predetermined heat keeping temperature during heat keeping are provided. Reference numeral 85 denotes a heating coil driving means having a built-in high frequency inverter circuit for receiving a control signal from the control means 81 and supplying a predetermined high frequency current to the heating coil 16. Separately from this, the output side of the control means 81 receives a control signal from the control means 81 and the lid heater driving means for driving the lid heater 56 so as to heat the heat radiating plate 47 and the inner lid 51.
86 and a code heater in response to a control signal from the control means 81
Code heater driving means 87 for turning on 26 is provided. When cooking by the rice cooking control means 82, the heating coil
16, the cord heater 26, and the lid heater 56 are configured to heat an object to be cooked in the pan 11. In addition, after the rice cooking by the rice cooking control means 82 is finished and the cooked food in the pan 11 is cooked as rice, it automatically shifts to heat insulation by the heat insulation control means 83, and the temperature detected by the pan temperature sensor 21 is reached. Based on this, by adjusting the heating of the pan 11 by the heating coil 16 and the cord heater 26, the rice is kept at a predetermined temperature (about 70 ° C. to 76 °
(° C). In particular, the heating by the cord heater 26 will be supplementarily explained. After the rice is cooked, the heat of the cord heater 26 is generated at a stable temperature of about 73 ° C. until the temperature of the rice drops from about 100 ° C. to a temperature of about 73 ° C. Let the metal plate 29 radiate heat into the gap 30 between the lid 5 and the rice cooker body 1 to suppress the cooling due to the intrusion of outside air from the gap 30;
The flange part 14 of the pan 11 is heated. In addition, the flange 14 of the pan 11 is also heated by the code heater 26 during the period when the rice is reheated during the heat insulation, and moisture generated by the heating of the rice
It is comprised so that it may prevent dew condensation on the inner surface upper part. Next, the operation of the above configuration will be described. When rice and water, which are to-be-cooked objects, are put into the pan 11 and rice cooking is started by the rice cooking control means 82, the temperature of the lid 5 is immediately detected by the lid temperature sensor 57. The detected temperature at this time is stored and held in the control means 81 until the temperature is changed from rice cooking to heat retention and the state is turned off. Then, based on the temperature detection of the bottom of the pan 11 by the pan temperature sensor 21, the bottom of the pan 11 is heated by the heating coil 16, and the water temperature in the pan 11 is increased to 45-60 ° C.
A meal prepared for ~ 20 minutes. After that, the pot 11 is heated strongly by the heating coil 16 to boil the cooking object. When the temperature of the bottom of the pan 11 becomes 90 ° C. or higher during the boiling heating and the temperature of the lid 5 is stabilized at 90 ° C. or higher, the pan 11
Assuming that the inside is in a boiling state, the process shifts to boiling continuous heating with a heating amount reduced more than before. It should be noted that the fact that the temperature of the lid 5 is stable at 90 ° C. or higher is detected by the rate of temperature rise of the detected temperature from the lid temperature sensor 57. In this boiling detection, the pan temperature sensor 21 and the lid temperature sensor 57 can confirm that both the bottom of the pan 11 and the lid 5 have reached 90 ° C. or more, and it is accurate that the inside of the pan 11 has completely boiled. Can be detected well. If either the bottom of the pan 11 or the lid 5 reaches a detected temperature that is not normally 120 ° C. or higher, the control means 81 determines that the temperature is abnormal and reduces the amount of heating in cooking rice. Or, it is turned off to stop all operations, or shifts to unevenness, which will be described later, or heat is maintained to prevent abnormal heating. Conversely, either the bottom of the pan 11 or the lid 5 has reached 90 ° C. or more and a predetermined time (for example, 5 minutes) has passed, but any of the bottom of the pan 11 or the lid 5 other than that. When the temperature is below 90 ° C, the pan temperature sensor 21 or the lid temperature sensor 57 in the low temperature state determines that the temperature detection accuracy has deteriorated for some reason (dirt, tilt, poor contact, etc.). In the same way, reduce the amount of heating in rice cooking heating, or turn it off to stop all operations,
Move to spotty or keep warm and deal with this. When shifting to boiling continuation, the rice cooking control means 82 starts lid heating by the lid heater 56. The lid heating here is managed by the detected temperature of the lid temperature sensor 57 so that the temperature of the inner lid 51 becomes 100 to 110 ° C. And if the bottom part of the pan 11 or the side part of the pan 11 raises a predetermined temperature, cooking will be detected and it will shift to unevenness. During unevenness, the lid heater 56 is controlled by temperature control by the temperature detected by the lid temperature sensor 57.
The power is cut off to prevent dew on the inner lid 51 and at the bottom of the pan 11 or the side of the pan 11 so that the rice is kept at a high temperature (98-100 ° C) to the extent that it does not burn. Manage temperature. The unevenness is continued for a predetermined time (15 to 20 minutes), and when the unevenness is completed, the operation shifts to heat retention by the heat retention control means 83. When the temperature is kept, the lid temperature sensor is detected immediately after the start of cooking until the rice in the pan 11 is lowered to the temperature.
The lower the detected temperature of 57, the more the amount of heating of the side surface of the pan 11 by the cord heater 26 is increased, and the side surface of the pan 11 is heated. Specifically, when the temperature detected by the lid temperature sensor 57 immediately after the start of cooking is 10 ° C or less, the heating amount (power consumption) of the side surface of the pan 11 by the code heater 26 is 90% of the maximum.
When the detection temperature is over 10 ° C and less than 30 ° C, the heating amount is 80% of the maximum, and when the detection temperature is 30 ° C or more, the heating amount is 50% of the maximum. However, this is merely an example, and the relationship between the temperature detected by the lid temperature sensor 57 immediately after the start of rice cooking and the heating amount of the code heater 26 may be set as appropriate according to the structure of the rice cooker. When it is detected by the pan temperature sensor 21 that the rice in the pan 11 has been lowered to the set temperature, the heat control means 83 heats the bottom and side lower portions of the pan 11 with the heating coil 16, and the lid The inner lid 51 is heated by the heater 56 slightly higher than the temperature of the rice. At the same time, the side surface of the pan 11 is heated by the cord heater 26, and the temperature is controlled so that the rice in the pan 11 is not dried and a large amount of dew does not adhere. And the pan temperature sensor 21 brought into contact with the bottom of the pan 11
By adjusting the amount of heating to the pan 11 by the heating coil 16 and the cord heater 26 according to the detected temperature, the temperature of the rice in the pan 11 is maintained at 70 to 76 ° C. Even when keeping warm,
When the detection temperature of any one of the two sensors 21 and 57 is abnormally high or low, it is determined as abnormal, and the state is switched to the off state to prevent the abnormality. As described above, according to this embodiment, the lid 5 covering the upper surface opening of the pan 11 is provided with the lid temperature sensor 57 as lid temperature detection means, and the control means 81 automatically keeps the heat from the cooked rice. In the rice cooker to be performed, the control means to vary the amount of heating of the side surface of the pan 11 after the completion of rice cooking by the code heater 26 which is the pan side surface detecting means according to the detection temperature of the lid temperature sensor 57 at the start of rice cooking Make up 81. In this case, the lid temperature sensor 57 that originally detects the temperature of the lid body 5 is used to detect the temperature of the lid body 5 immediately after the start of cooking, and the code after the completion of cooking is determined according to the detected temperature. The amount of heating of the side surface of the pan 11 by the heater 26 can be varied. Therefore, even if it does not increase a new temperature detection means, the heating amount to the side surface of the pan 11 after completion of the rice cooking process can be optimized at a low cost. Incidentally, it is conceivable to change the amount of heating to the side of the pan 11 after the completion of cooking based on the temperature of the pan 11 at the start of rice cooking. For example, hot water instead of water is used to cook rice quickly. When it is put together, the temperature much higher than the room temperature is detected by the pan temperature sensor 21, and the determination of the amount of heating to the side surface of the pan 11 assuming the room temperature is not performed correctly. In addition, it is known that cold water can be cooked deliciously when the room temperature is high, such as in summer, but even when such cold water is added together with rice, the difference from the actual room temperature increases, The amount of heating to the side cannot be determined correctly. In that respect, since the temperature detected from the lid temperature sensor 57 immediately after cooking is hardly affected by the water temperature in the pan 11, it is possible to accurately heat the side surface of the pan 11 in consideration of the influence of the room temperature. In actual use, it is also possible to stop cooking and immediately cook rice. In such a case, the pan 11 is removed from the rice cooker body 1 and washed, and the weighed rice is put into the pan 11. As the rice is sharpened and the water is adjusted, the temperature of the lid 5 also decreases to room temperature. Therefore, even when cooking rice immediately after heat insulation, in the present embodiment, heating of the side surface of the pan 11 in consideration of the influence of room temperature can be performed accurately. The present invention is not limited to the above-described embodiments, and various modifications can be made. The setting of the heating amount described above is merely an example, and may be arbitrarily set within a range not departing from the gist of the invention. According to the rice cooker of the present invention, the amount of heating to the pan after the completion of the rice cooking process can be optimized at a low cost without adding new temperature detection and detection means. .
Moreover, the heating to the pan which considered the influence of room temperature can be performed correctly.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a sectional view of a rice cooker showing an embodiment of the present invention. FIG. 2 is a block diagram showing a functional configuration of the control system. [Explanation of symbols] 5 Lid body 11 Pan 57 Lid temperature sensor (temperature detection means)

Claims (1)

[Claims] [Claim 1] In a rice cooker which includes a temperature detection means on a lid covering the upper surface of the pan and automatically keeps the temperature from cooking, depending on the temperature of the temperature detection means during rice cooking The rice cooker is configured to vary the heating of the pan after the completion of rice cooking.