JP2010022449A - Rice cooker - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a rice cooker capable of preventing the burn of rice and cooking delicious rice even when the rice is cooked under such a condition that the detection of a lid temperature detection means is rusty. <P>SOLUTION: The rice cooker includes: a first comparator 11a for detecting that a pot temperature detection means 4 becomes a prescribed temperature or higher; a second comparator 11b for detecting that the lid temperature detection means 8 for detecting the boiling of water inside a pot has a prescribed temperature or higher; and a rice cooking power determination means 11d for determining rice cooking power thereafter on the basis of the time decided by a rice cooking capacity decision means 11c for measuring elapsed time from output by the first comparator to output by the second comparator. The second comparator has a first detection temperature and a second detection temperature which is the temperature lower than the first detection temperature. Thus, the burn of the rice and overflowing are prevented, and the delicious rice is cooked with an optimum heating amount. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a rice cooker that stably detects the progress of rice cooking and performs appropriate heating control.

  Conventionally, this type of rice cooker is provided with a lid temperature detecting means for detecting the steam temperature of the pot, in addition to the pot temperature detecting means for detecting the temperature of the pot. The rice cooking capacity is detected based on the elapsed time from when the temperature reaches the predetermined temperature until the lid temperature detecting means reaches the predetermined temperature, and the subsequent rice cooking power is determined based on the rice cooking capacity based on the detection result.

That is, if the elapsed time from when the pan temperature detecting means reaches the predetermined temperature until the lid temperature detecting means reaches the predetermined temperature is short, it is determined that the rice cooking capacity is small, and thereafter, low power is supplied to the pan. Conversely, if the elapsed time is long, it is determined that the rice cooking capacity is large, and thereafter, high power is supplied to the inner pot and cooked (see, for example, Patent Document 1).
Japanese Patent Laid-Open No. 62-155814

  However, in the conventional configuration, the detection temperature of the rice cooking capacity is set in a temperature zone combined with the detection of the start of boiling, and in the case where the detection of the lid temperature detection means is dull, for example, the lid temperature detection means A state where the heat of steam does not transfer well to the lid temperature detection means, such as rice grains sticking to the heat sensitive part, the temperature of the outside air is low, and the rice cooker lid itself is started cold, etc. When it happens that the detection of boiling of water in the pan is delayed, the temperature of the lid temperature detecting means may be stabilized without the lid temperature detecting means reaching the predetermined detection temperature. Even though the water in the pan was boiling, it was judged that it was not heated yet, and continued to supply high power to the pan, which had the problem that the rice burned and delicious rice could not be cooked.

  This invention solves the said conventional subject, Even if the situation where the detection of a cover temperature detection means dulls occurs, providing a rice cooker which can cook delicious rice by preventing scorching of rice. Objective.

  In order to solve the conventional problems, the rice cooker of the present invention includes a pan, a pan heating means for heating the pan, a lid that covers the opening of the pan, and a pan temperature detection means for detecting the temperature of the pan. A first comparator for detecting that the pan temperature detecting means has reached a predetermined temperature, a lid temperature detecting means for detecting boiling of water inside the pot, and a lid temperature. A second comparator for detecting that the detection means has reached a predetermined temperature and a rice cooking capacity determination means for measuring an elapsed time until the first comparator outputs and the second comparator outputs. And the rice cooking power determination means for determining the subsequent rice cooking power based on the time determined by the rice cooking capacity determination means, and the energization for controlling the energization amount of the pot heating means according to the rice cooking power determined by the rice cooking power determination means. An amount control means, wherein the second comparator has a first detection temperature and the first detection temperature. If the second detected temperature is lower than the detected temperature of the first comparator and the second comparator is delayed from reaching the first detected temperature after the output of the first comparator, The time to start boiling is predicted by the time to reach the detected temperature.

As a result, the detection of the lid temperature detection means becomes dull, for example, rice grains adhere to the heat sensitive part of the lid temperature detection means, the contact with the lid becomes poor, and the detection of the boiling of water inside the pan is delayed, and the pot temperature detection means Predicting the time when the second detected temperature starts to boil in an earlier time zone than the second comparator detected by the lid temperature detecting means after the first comparator detected by When reaching the detected temperature exceeds the predicted time, the heating control to the pan heating means is changed, so that the rice can be prevented from being burned and delicious rice can be cooked.

  In the rice cooker of the present invention, detection abnormality of the lid temperature detection means, for example, rice grains adhere to the heat sensitive part of the lid temperature detection means, the contact with the lid body becomes worse, and detection of boiling of water inside the pan is delayed. However, it is possible to cook delicious rice without scorching the rice, and it is possible to suppress heating before spilling.

  1st invention is a pan, the pan heating means which heats a pan, the cover body which covers the opening part of a pan, the pan temperature detection means which detects the temperature of a pan, and a pan temperature detection means over predetermined temperature The first comparator for detecting that the lid has been detected, the lid temperature detecting means for detecting the boiling of the water in the pan, and the lid temperature detecting means being equal to or higher than a predetermined temperature. The second comparator for detecting the rice, the first comparator output, and the rice cooking capacity determination means for measuring the elapsed time until the second comparator outputs, and the time determined by the rice cooking capacity determination means A rice cooking power determining means for determining the subsequent rice cooking power, and an energizing amount control means for controlling the energizing amount of the pot heating means according to the rice cooking power determined by the rice cooking power determining means, The comparator has a first detection temperature and a second temperature that is lower than the first detection temperature. When the second comparator has a known temperature and the second comparator delays reaching the first detection temperature after the output from the first comparator, the time to start boiling according to the time to reach the second detection temperature in advance Is to be predicted.

  As a result, the detection of the lid temperature detecting means becomes dull, for example, rice grains etc. adhere to the heat sensitive part of the lid temperature detecting means and the contact with the lid body becomes worse, so that the boiling of water inside the pot cannot be detected, and the pot temperature When the second comparator detected by the lid temperature detecting means is delayed from reaching the first detected temperature after the first comparator detected by the detecting means is output, depending on the time to reach the second detected temperature in advance. A means for predicting the time to start boiling can be obtained, thereby reducing the amount of heating to the pan heating means, so that the rice can be prevented from being burned and delicious rice can be cooked.

  In the second invention, in particular, in the first invention, after the first comparator outputs a predetermined temperature until the second comparator outputs the second detected temperature, and thereafter By dividing the period until the first detection temperature is detected into two different processes, the time at which boiling begins at an early stage is predicted in advance, and the amount of heating to the pan heating means is controlled. Therefore, the amount of heating at the start of boiling can be suppressed to prevent spilling.

  In the third invention, in particular, in the first invention, when an elapsed time from when the second comparator outputs the second detection temperature to when the first detection temperature is output exceeds a predetermined time. Since the rice cooking process can be transferred to the next process, cooking is performed in a situation where the detection of the lid temperature detection means is dull, and heating to the pot heating means is also extremely slow when reaching the first detection temperature. The amount can be reduced to prevent scorching of rice and cook delicious rice.

  In particular, according to the fourth invention, in the second invention, the set time from the output of the second detected temperature to the transition to the next step is determined by the elapsed time from the output of the first detected temperature. Since it can be changed according to the elapsed time from the output of the first comparator until the second comparator outputs the second detected temperature, the rice can be cooked deliciously with the optimum heating amount.

In the fifth invention, particularly in the second to fourth inventions, the second comparator has a third detection temperature lower than the second detection temperature, and the second comparator is the first at the start of cooking rice. When a temperature lower than the detection temperature of 3 is output, the set time until the rice cooking process is shifted to the next process after the second comparator outputs the second detection temperature after the start of rice cooking is set short. By determining whether the rice cooker body has started cooking from a warmed state or whether it has started cooking from a cold state, the temperature rise rate variation of the lid temperature detection means during rice cooking will be judged and optimal A means to cook rice with a simple heating amount can be obtained.

  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)
As shown in FIG. 1, the rice cooker in this Embodiment equips the main body 1 of the rice cooker with the pan 2 so that attachment or detachment is possible.

  A pan heating means 3 for heating the pan 2 and a pan temperature detecting means 4 for detecting the temperature of the pan 2 are arranged inside the main body 1.

  The pot heating means 3 may be a heater, a coil for induction heating of the pot 2, or any heating means.

  The lid body 5 covering the upper surface opening of the pan 2 is rotatably supported by the hinge shaft 6 and installed so as to be opened and closed.

  On the lower surface of the lid 5, an inner lid 7 and a lid temperature detecting means 8 for detecting the temperature of the inner lid 7 and detecting boiling of water inside the pan 2 are provided between the lid 2 and the pot 2. In the lid temperature detecting means 8, the heat sensitive part 9 is in contact with the inner lid 7.

  The inner lid 7 is detachably attached to the lid 5 so as to be easily maintained. Further, the lid 5 is provided with a steam cylinder 10 that communicates with the opening on the upper surface of the pan 2 and discharges the steam in the pan 2 to the outside of the main body 1.

  The control means 11 has a microcomputer mounted on a circuit board (not shown). The control means 11 is a rice cooking program stored in the microcomputer in advance based on an operation command input by the user via the operation panel 12, a signal input from the pan temperature detection means 4 and the lid temperature detection means 8 by software. Thus, the heating control of the pan 2 is performed. The control means 11 controls the heating amount of the pan heating means 3 by the energization rate of each heating means.

  The operation flow of the control means 11 is shown in FIG.

  That is, the control means 11 detects the first comparator 11a that detects that the pan temperature detecting means 4 has become a predetermined temperature or higher, and the first comparator 11a that detects that the lid temperature detecting means 8 has become the predetermined temperature or higher. Rice cooking capacity determination means 11c for determining the rice cooking capacity by measuring the elapsed time until the second comparator 11b and the first comparator 11b output the second comparator 11b, and the rice cooking capacity The energizing amount of the pot heating means 3 is controlled according to the rice cooking power determining means 11d for determining the subsequent rice cooking power based on the rice cooking capacity determined by the determining means 11c and the rice cooking power determined by the rice cooking power determining means 11d. And an energization amount control means 11e.

  And the control means 11 controls the energization amount of the pan heating means 3 by the time and detection temperature of each detection temperature which the 1st comparator 11a outputs and the 2nd comparator 11b outputs.

  About the rice cooker comprised as mentioned above, the operation | movement and an effect | action are demonstrated below.

  The user puts rice corresponding to the rice to be cooked and water corresponding to the amount of the rice into two pots and sets the main body 1 in a predetermined state.

  If operation start operation is performed by the control means 11, a rice cooking process will be implemented by the rice cooking program previously memorize | stored in the microcomputer.

  The rice cooking process is roughly divided into each process of water immersion, rice cooking capacity determination, boiling detection, cooking / boiling maintenance, and steaming.

  Here, the figure which showed the temperature change during the cooking of the cooking thing in the pan when cooking rice in a normal state and the cover temperature detection means 8 is shown in FIG.

  In FIG. 3, rice cooking is started, and first a water immersion process is entered.

  The soaking process is a process of allowing the rice to absorb water by holding the rice at 55 to 60 ° C. In this submerging step, this temperature is a necessary condition for the rice in the pan 2 to absorb the water sufficiently evenly.

  Next, if it progresses to a rice cooking capacity | capacitance determination process, the pan 2 which has accommodated rice and water will be heated by the pan heating means 3 by the fixed heating amount, and the temperature inside the pan 2 will rise gradually.

  The temperature of the pan 2 is detected by the pan temperature detecting means 4 provided so as to come into contact with the bottom of the pan 2, and the first comparator 11a compares whether or not the pan temperature detecting means 4 has exceeded a predetermined temperature. And when it becomes more than predetermined temperature, the rice cooking capacity determination means 11c starts time measurement.

  Furthermore, when the pan 2 is heated at a constant heating amount by the pan heating means 3, the temperature inside the pan 2 gradually rises, but the steam reaches the inner lid 7 until the water inside the pan 2 boils. Since it hardly rises, the temperature of the heat sensitive part 9 of the lid temperature detecting means 8 that is in contact with the upper part of the inner lid 7 hardly rises.

  However, when the water in the pot 2 boils, a large amount of steam hits the inner lid 7, so the temperature of the heat sensitive part 9 of the lid temperature detecting means 8 rises rapidly.

  At this time, the temperature of the lid temperature detection means 8 provided in the lid 5 first passes the second detection temperature 12 and outputs that the second comparator 11b has passed, and the process of determining the rice cooking capacity The rice cooking capacity determination means 11c stores the time so that the rice cooking capacity determination means 11c detects the rice cooking capacity.

  That is, the elapsed time from the output of the first comparator 11a detected by the pan temperature detecting means 4 to the output of the second comparator 11b detected by the lid temperature detecting means 8 is such that the heat capacity increases. Since it becomes so long, rice cooking capacity can be determined from this elapsed time.

  And the rice cooking power determination means 11d determines rice cooking power according to rice cooking capacity by the output of this rice cooking capacity determination means 11c.

  The heating amount of the pan heating means 3 is controlled according to the rice cooking power determined by the rice cooking power determination means 11d. After detecting the rice cooking capacity, the process proceeds to the boiling detection process.

  When entering the boiling detection step, it may be determined that the time to reach boiling is near. In this step, the amount of heating is reduced to a level of, for example, about 90% with respect to the rice cooking amount determination step, and the occurrence of spilling due to sudden boiling is prevented.

  Further, energization is continued, the second comparator 11b outputs that the temperature of the lid temperature detection means 8 has passed the first detection temperature 13, and the process proceeds to the cooking and boiling maintaining step.

  At this time, the inside of the pan 2 has already boiled, and it is only necessary to heat the minimum level at which the boiling state can be maintained by further reducing the heating amount.

  Especially when it is judged that the amount of cooked rice is small in the rice cooking capacity judging step, the temperature of the pan 2 may rise at a stretch until the rice is dried or burnt unless the amount of heating is reduced here. It is better to drop the amount greatly.

  In the cooking process, heat is applied to the absorbed rice and then cooked. In the boiling maintenance process, the boiling is maintained and the starch of rice is gelatinized to make rice.

  When the water remaining in the bottom of the pan 2 is absorbed and evaporated by the rice, the temperature at the bottom of the pan 2 rises to a higher temperature than the boiling temperature, so that the temperature detected by the pan temperature detecting means 4 detects this temperature change. Detect and move to the uneven process.

  Also in this cooking and boiling maintaining step, when the elapsed time exceeds a predetermined time, the heating amount of the pan heating means 3 is reduced to prevent the rice from burning.

  In the unevenness process, the cooked rice is steamed to finish the pan 2 uniformly, and the cooking is completed in this process.

  In contrast to this, for example, foreign matter such as rice grains adheres to the periphery of the heat-sensitive part 9 of the lid temperature detection means 8, or the rice cooker is cooked in a situation where the rice cooker starts abnormally from a state in which the rice cooker is abnormally cooled by the outside air temperature. The figure which showed the temperature change during rice cooking with the cooking thing in the time pot and the lid | cover temperature detection means 8 is shown in FIG.

  In FIG. 4, rice cooking is started, and the process goes to the boiling detection process through the rice cooking capacity determination process.

  The first detection temperature 13 is set to a temperature at which it is detected that the inside of the pan 2 has started to boil, but depending on the conditions, the temperature of the heat-sensitive part 9 may reach before reaching the first detection temperature 13. A phenomenon that does not increase occurs.

  At this time, the heating will continue until it is determined that it will not boil.

  Therefore, in this case, the time required for the boiling detection step is estimated based on the time required for the rice cooking capacity determination step. That is, when time is required for the rice cooking capacity determination step, it is determined that the amount of rice cooking is large, and it is determined that the time required for the completion of the boiling detection step is long.

  Conversely, when the time required for the rice cooking capacity determination step is short, it is determined that the amount of rice cooking is small, and it is determined that the time required for the end of the boiling detection step is short.

  Therefore, when the predetermined time set has elapsed, the process proceeds to the cooking and boiling maintaining process without waiting for the detection of the first detection temperature 13.

  After entering the boil-up / boiling maintenance process, boil is maintained as in the case of cooking in a normal state to make rice, and after the transition to the uneven process, the cooking is terminated.

  As described above, in the present embodiment, when the detection by the lid temperature detecting means 8 is slow, the time for boiling in the pan is predicted in advance, and the process proceeds to the next step. Can cook.

  The same effect can be obtained even if the set time from the passage of the second detection temperature 12 described in the present embodiment to the transition to the boiling detection step is simply set to a fixed time. In this case, the microcomputer program can be simplified.

  In addition, although it is described that the amount of heating is changed in the rice cooking capacity determination step and the boiling detection step, if a means for preventing spilling is set even if heating is continued with the same amount of heating, it will be possible to cook rice The same effect can be obtained.

  Further, when the end of the boiling detection process is normally detected by the second comparator, the time required for this process can be used as a value for correcting the determination value of the rice cooking capacity determination.

(Embodiment 2)
Next, the rice cooker in Embodiment 2 of this invention is demonstrated.

  In the embodiment of the present invention, the basic configuration of the rice cooker and the operation during rice cooking are the same as those in the first embodiment.

  In FIG. 3, when starting rice cooking, for example, when the rice cooker body is warmed, such as when cooking rice continuously, and starting rice cooking from a cold state in a low temperature environment, Even when the amount of cooked rice is the same, the time from when cooking is started until the lid temperature detecting means 8 passes the second detected temperature 12 differs.

  Therefore, if the third detection temperature 14 that is lower than the second detection temperature 12 is set and the second comparator 11b detects that the temperature is lower than the third detection temperature at the start of cooking, the first detection temperature is used. 13 and the time to reach the second detection temperature 12 is determined to be long, and the setting is changed to a short time to limit the time until the heating amount is reduced after passing through the first detection temperature 13, The setting of the heating amount after passing the first detection temperature 13 is changed to a small amount.

  Thereby, the detection level of the cover temperature detection means 8 by the temperature of the rice cooker main body at the time of a rice cooking start can be stabilized.

  In the present embodiment, it has been described that the subsequent heating conditions are divided into two stages according to the third detected temperature 14, but if the number of detected temperatures is increased and the stages are divided finely, more accurate heating is performed, It goes without saying that delicious rice can be cooked stably.

  As described above, the rice cooker according to the present invention can cook delicious rice by preventing the scorching of the rice, even if the condition that the detection of the lid temperature detection means becomes dull occurs, and can cook delicious rice. Applicable in general.

Sectional drawing of the rice cooker in Embodiment 1, 2 of this invention Control block diagram of rice cooker in Embodiments 1 and 2 of the present invention Explanatory drawing which shows the temperature change during rice cooking in the normal state of the rice cooker in Embodiment 1, 2 of this invention. Explanatory drawing which shows the temperature change during rice cooking in the state with a dull lid temperature detection of the rice cooker in Embodiment 1, 2 of this invention.

Explanation of symbols

2 pan 3 pan heating means 4 pan temperature detecting means 5 lid 7 inner lid 8 lid temperature detecting means 11 control means 11a first comparator 11b second comparator 11c rice cooking capacity judging means 11d rice cooking power determining means 11e energizing amount Control means 12 Second detection temperature 13 First detection temperature 14 Third detection temperature

Claims (5)

A pan whose opening is opened and closed by a lid, a pan heating means for heating the pan, a pan temperature detecting means for detecting the temperature of the pan, and that the pan temperature detecting means has reached a predetermined temperature or more. A first comparator for detecting; a lid temperature detecting means provided on the lid; a second comparator for detecting that the lid temperature detecting means has reached a predetermined temperature; and the first comparison. Rice cooking capacity determination means for measuring the elapsed time until the second comparator outputs and the rice cooking power determination means for determining the subsequent rice cooking power based on the time determined by the rice cooking capacity determination means And an energization amount control means for controlling the energization amount of the pan heating means according to the rice cooking power determined by the rice cooking power determination means, wherein the second comparator has a first detected temperature and the first Having a second detected temperature that is lower than the detected temperature of the first If the comparator outputs delayed second comparator that reaches the first detection temperature, cooker which is adapted to predict the time to start boiling the time to reach a pre-second detection temperature. Between the time when the first comparator outputs a predetermined temperature and the time when the second comparator outputs the second detected temperature, and thereafter until the second comparator detects the first detected temperature. The rice cooker of Claim 1 formed by dividing | segmenting between into two different processes. The rice cooking process is shifted to the next process when an elapsed time from when the second comparator outputs the second detected temperature to when the first detected temperature is output exceeds a predetermined time. The described rice cooker. The second comparator after the first comparator outputs the set time from the output of the second detected temperature to the transition to the next process according to the elapsed time from the output of the first detected temperature. The rice cooker according to claim 2, wherein the rice cooker is changed according to an elapsed time until the second detection temperature is output. The second comparator has a third detection temperature lower than the second detection temperature, and when the second comparator outputs a temperature lower than the third detection temperature at the start of rice cooking, rice cooking starts. The rice cooker according to any one of claims 2 to 4, wherein a set time from when the second comparator outputs the second detected temperature later to when the rice cooking process is shifted to the next process is set short. .

Images